WO2017073548A1 - Sealing agent for liquid crystal display elements, vertically conducting material and liquid crystal display element - Google Patents

Abstract

One purpose of the present invention is to provide a sealing agent for liquid crystal display elements, which is capable of achieving a good balance between curability at low temperatures and storage stability. Another purpose of the present invention is to provide: a vertically conducting material which is obtained using this sealing agent for liquid crystal display elements; and a liquid crystal display element. The present invention is a sealing agent for liquid crystal display elements, which contains a curable resin and a thermal curing agent, and wherein: the curable resin contains a curable resin having an epoxy group; the thermal curing agent contains an amine adduct compound that has a structure derived from an epoxy resin and a structure derived from an amine compound; and an amine compound, from which the amine adduct compound is derived, is an alkyl imidazole having an alkyl group with 1-20 carbon atoms.

Description

Sealant for liquid crystal display element, vertical conduction material, and liquid crystal display element

The present invention relates to a sealant for a liquid crystal display element that can achieve both low-temperature curability and storage stability. Moreover, this invention relates to the vertical conduction material and liquid crystal display element which use this sealing compound for liquid crystal display elements.

In recent years, as a method of manufacturing a liquid crystal display element such as a liquid crystal display cell, a curable resin and a light as disclosed in Patent Document 1 and Patent Document 2 from the viewpoint of shortening tact time and optimizing the amount of liquid crystal used. A system called a dripping method using a photothermal combination curing type sealant containing a polymerization initiator and a thermosetting agent is used.
In the dropping method, first, a rectangular seal pattern is formed on one of the two substrates with electrodes by dispensing. Next, liquid crystal microdrops are dropped into the sealing frame of the substrate in a state where the sealing agent is uncured, the other substrate is superposed under vacuum, and the sealing portion is irradiated with light such as ultraviolet rays to perform temporary curing. Thereafter, heating is performed to perform main curing, and a liquid crystal display element is manufactured. At present, this dripping method has become the mainstream method for manufacturing liquid crystal display elements.

From the viewpoint of energy saving and liquid crystal stability, it is desired that the sealant be thermally cured by heating at a low temperature for a short time. Conventionally, a thermosetting agent or a curing accelerator having a low melting point has been used as a method for curing the sealing agent by heating at a low temperature for a short time. However, when a thermosetting agent or a curing accelerator having a low melting point is used, the reaction is likely to occur even near room temperature, so that the storage stability of the sealing agent is lowered.

JP 2001-133794 A International Publication No. 02/092718

An object of this invention is to provide the sealing compound for liquid crystal display elements which can make low temperature sclerosis | hardenability and storage stability compatible. Another object of the present invention is to provide a vertical conduction material and a liquid crystal display element using the sealing agent for a liquid crystal display element.

The present invention is a liquid crystal display element sealing agent containing a curable resin and a thermosetting agent, wherein the curable resin contains a curable resin having an epoxy group, and the thermosetting agent is an epoxy resin. A liquid crystal display device comprising an amine adduct compound having a structure derived from and a structure derived from an amine compound, wherein the amine compound from which the amine adduct compound is derived is an alkyl imidazole having an alkyl group having 1 to 20 carbon atoms Sealing agent.
The present invention is described in detail below.

The present inventor has disclosed a sealing agent for liquid crystal display elements that can achieve both low-temperature curability and storage stability by using an adduct of an alkylimidazole having an alkyl chain having a specific length and an epoxy resin as a thermosetting agent. The inventors have found that the present invention can be obtained and have completed the present invention.

The sealing agent for liquid crystal display elements of this invention contains a thermosetting agent.
The said thermosetting agent has the structure derived from an epoxy resin, and the structure derived from an amine compound, and this amine compound contains the amine adduct compound which is the alkyl imidazole mentioned later. By using such an amine adduct compound as the thermosetting agent, it is possible to enhance curability at low temperatures while maintaining excellent storage stability.

As the epoxy resin from which the amine adduct compound is derived, for example, those described later as the curable resin having an epoxy group can be used. Among these, an epoxy resin having an aromatic ring is preferable. When the epoxy resin from which the amine adduct compound is derived has an aromatic ring, the storage stability of the obtained sealing agent for liquid crystal display elements can be further enhanced. The epoxy resin from which the amine adduct compound is derived is more preferably at least one selected from the group consisting of bisphenol A type epoxy resins, bisphenol F type epoxy resins, and bisphenol E type epoxy resins.

The amine compound from which the amine adduct compound is derived is an alkylimidazole having an alkyl group with 1 to 20 carbon atoms.
As the alkyl imidazole in which the alkyl group has 1 to 20 carbon atoms, those having 1 to 2 carbon atoms in the alkyl group are preferable, and 2-methylimidazole is more preferable.

As the amine adduct compound, a compound represented by the following formula (1-1) and / or a compound represented by the following formula (1-2) is preferably used.
A sealing agent for a liquid crystal display element comprising a curable resin and a thermosetting agent, wherein the curable resin contains a curable resin having an epoxy group, and the thermosetting agent is represented by the following formula (1-1): A sealant for a liquid crystal display device containing a compound represented by formula (1) and / or a compound represented by the following formula (1-2) is also one aspect of the present invention.

In Formula (1-1) and Formula (1-2), R ¹ is an alkyl group having 1 to 20 carbon atoms. In Formula (1-1), R ² and R ³ are hydrogen or methyl. Each group may be the same or different.

In addition, the thermosetting agent includes a compound represented by the following formula (2-1) as a compound represented by the above formula (1-1) and / or a compound represented by the above formula (1-2), At least one selected from the group consisting of a compound represented by the following formula (2-2), a compound represented by the following formula (2-3), and a compound represented by the following formula (2-4) It is preferable to contain.

A preferable upper limit of the average particle size of the amine adduct compound is 3 μm. The gap defect of the obtained liquid crystal display element can be suppressed because the average particle diameter of the said amine adduct compound is 3 micrometers or less. Although there is no particular lower limit of the average particle size of the amine adduct compound, the substantial lower limit is 0.1 μm.
When a commercially available amine adduct compound having an average particle diameter exceeding 3 μm is used, the average particle diameter can be reduced to 3 μm or less by performing treatments such as pulverization and classification.
In the present specification, the average particle size of the amine adduct compound and the maximum particle size described later are obtained by measuring the amine adduct compound before blending with the sealant using a laser diffraction particle size distribution analyzer. Means the value to be As the laser diffraction particle size distribution measuring device, Mastersizer 2000 (manufactured by Malvern) or the like can be used.

A preferable upper limit of the maximum particle size of the amine adduct compound is 5.0 μm. When the maximum particle size of the amine adduct compound is 5.0 μm or less, the obtained liquid crystal display device is more excellent in gap retention. A more preferable upper limit of the maximum particle size of the amine adduct compound is 4.5 μm. There is no particular lower limit for the maximum particle size of the amine adduct compound, but the substantial lower limit is 0.1 μm.

In the amine adduct compound, in the particle size distribution of the amine adduct compound measured by the laser diffraction particle size distribution analyzer, the content ratio of particles having a particle diameter of 3.0 μm or less is 99% or more by volume frequency. preferable. When the content ratio of the particles having a particle diameter of 3.0 μm or less is 99% or more by volume frequency, the obtained liquid crystal display element is more excellent in gap retention. The content ratio of particles having a particle diameter of 3.0 μm or less is most preferably 100%.

The content of the amine adduct compound is preferably 0.3 parts by weight and preferably 15 parts by weight with respect to 100 parts by weight of the curable resin. When the content of the amine adduct compound is within this range, the obtained sealing agent for liquid crystal display elements is excellent in low-temperature curability and excellent in the effect of suppressing liquid crystal contamination. A more preferred lower limit of the content of the amine adduct compound is 0.4 parts by weight, a more preferred upper limit is 12 parts by weight, a still more preferred lower limit is 0.5 parts by weight, and a still more preferred upper limit is 10 parts by weight.

The thermosetting agent may contain other thermosetting agents in addition to the amine adduct compound.
As said other thermosetting agent, a hydrazide type hardening | curing agent, an imidazole type hardening | curing agent, a polyhydric phenol type hardening | curing agent, an acid anhydride type hardening | curing agent etc. are mentioned, for example. Of these, hydrazide-based curing agents are preferably used.

Examples of the hydrazide-based curing agent include 1,3-bis (hydrazinocarboethyl-5-isopropylhydantoin), sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, malonic acid dihydrazide, and the like. Examples thereof include Amicure VDH, Amicure UDH (all manufactured by Ajinomoto Fine Techno Co.), SDH, IDH, ADH (all manufactured by Otsuka Chemical Co., Ltd.), MDH (manufactured by Nippon Finechem Co., Ltd.), and the like.

When the other thermosetting agent is contained, the total content of the thermosetting agent is preferably 1 part by weight with respect to 100 parts by weight of the curable resin, and 50 parts by weight with respect to the preferable upper limit. When the content of the entire thermosetting agent is within this range, the obtained sealing agent for liquid crystal display elements is more excellent in thermosetting and coating properties. The upper limit with more preferable content of the said whole thermosetting agent is 30 weight part.

The sealing agent for liquid crystal display elements of this invention contains curable resin.
The curable resin contains a curable resin having an epoxy group.
Examples of the curable resin having an epoxy group include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, 2,2′-diallyl bisphenol A type epoxy resin, water Bisphenol type epoxy resin, propylene oxide added bisphenol A type epoxy resin, resorcinol type epoxy resin, biphenyl type epoxy resin, sulfide type epoxy resin, diphenyl ether type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, phenol novolac type Epoxy resin, orthocresol novolac type epoxy resin, dicyclopentadiene novolac type epoxy resin, biphenyl novolac type epoxy resin, naphthalene fe Examples include a novolac epoxy resin, a glycidyl amine epoxy resin, an alkyl polyol epoxy resin, a rubber-modified epoxy resin, and a glycidyl ester compound.

As what is marketed among the said bisphenol A type epoxy resins, jER828, jER828EL, jER1004 (all are the Mitsubishi Chemical company make), Epicron 850 (made by DIC company), etc. are mentioned, for example.
As what is marketed among the said bisphenol F-type epoxy resins, jER806, jER4004 (all are the Mitsubishi Chemical company make) etc. are mentioned, for example.
Examples of commercially available bisphenol E type epoxy resins include EPOX-MK R710, EPOX-MK R1710 (both manufactured by Printec Co., Ltd.) and the like.
As what is marketed among the said bisphenol S-type epoxy resins, Epicron EXA1514 (made by DIC Corporation) etc. are mentioned, for example.
Examples of commercially available 2,2′-diallylbisphenol A type epoxy resins include RE-810NM (manufactured by Nippon Kayaku Co., Ltd.).
As what is marketed among the said hydrogenated bisphenol type | mold epoxy resins, Epicron EXA7015 (made by DIC Corporation) etc. are mentioned, for example.
Examples of commercially available propylene oxide-added bisphenol A type epoxy resins include EP-4000S (manufactured by ADEKA).
Examples of commercially available resorcinol type epoxy resins include EX-201 (manufactured by Nagase ChemteX Corporation).
Examples of commercially available biphenyl type epoxy resins include jER YX-4000H (manufactured by Mitsubishi Chemical Corporation).
Examples of commercially available sulfide type epoxy resins include YSLV-50TE (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.).
Examples of commercially available diphenyl ether type epoxy resins include YSLV-80DE (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.).
Examples of commercially available dicyclopentadiene type epoxy resins include EP-4088S (manufactured by ADEKA).
Examples of commercially available naphthalene type epoxy resins include Epicron HP4032, Epicron EXA-4700 (both manufactured by DIC) and the like.
Examples of commercially available phenol novolac epoxy resins include Epicron N-770 (manufactured by DIC).
Examples of the ortho-cresol novolac type epoxy resin that are commercially available include epiclone N-670-EXP-S (manufactured by DIC).
As what is marketed among the said dicyclopentadiene novolak-type epoxy resins, epiclone HP7200 (made by DIC) etc. are mentioned, for example.
Examples of commercially available biphenyl novolac epoxy resins include NC-3000P (manufactured by Nippon Kayaku Co., Ltd.).
Examples of commercially available naphthalene phenol novolac type epoxy resins include ESN-165S (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.).
Examples of commercially available glycidylamine type epoxy resins include jER630 (manufactured by Mitsubishi Chemical), Epicron 430 (manufactured by DIC), and TETRAD-X (manufactured by Mitsubishi Gas Chemical).
Examples of commercially available alkyl polyol type epoxy resins include ZX-1542 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), Epiklon 726 (manufactured by DIC), Epolite 80MFA (manufactured by Kyoeisha Chemical Co., Ltd.), Denacol EX-611. (Manufactured by Nagase ChemteX Corporation).
Examples of commercially available rubber-modified epoxy resins include YR-450, YR-207 (both manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), Epolide PB (manufactured by Daicel Corporation), and the like.
Examples of commercially available glycidyl ester compounds include Denacol EX-147 (manufactured by Nagase ChemteX Corporation).
Other commercially available epoxy compounds include, for example, YH-300, YDC-1312, YSLV-80XY, YSLV-90CR (all manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), XAC4151 (manufactured by Asahi Kasei Co., Ltd.), jER1031 JER1032 (all manufactured by Mitsubishi Chemical Corporation), EXA-7120 (manufactured by DIC Corporation), TEPIC (manufactured by Nissan Chemical Industries, Ltd.), and the like.

The curable resin having an epoxy group may be a partial (meth) acryl-modified epoxy resin. The partial (meth) acryl-modified epoxy resin means a compound having one or more epoxy groups and (meth) acryloyl groups in one molecule, for example, having two or more epoxy groups in one molecule. It can be obtained by reacting a part of the epoxy group of the epoxy compound with (meth) acrylic acid.
In the present specification, the “(meth) acryl” means acryl or methacryl, and the “(meth) acryloyl group” means an acryloyl group or a methacryloyl group.

As what is marketed among the said partial (meth) acryl modified epoxy resins, UVACURE1561 (made by Daicel Ornex) etc. are mentioned, for example.

The preferable lower limit of the content of the curable resin having an epoxy group in 100 parts by weight of the curable resin is 1 part by weight, and the preferable upper limit is 100 parts by weight. When the content of the curable resin having an epoxy group is within this range, the obtained sealing agent for liquid crystal display elements is more excellent in adhesiveness. The minimum with more preferable content of the said curable resin which has an epoxy group is 2 weight part.

The curable resin may contain another curable resin in addition to the curable resin having an epoxy group. As said other curable resin, a (meth) acryl compound is preferable.
As the (meth) acrylic compound, for example, (meth) acrylic acid ester compound obtained by reacting (meth) acrylic acid with a compound having a hydroxyl group, (meth) acrylic acid and epoxy compound are reacted. Examples include epoxy (meth) acrylates obtained, urethane (meth) acrylates obtained by reacting an isocyanate compound with a (meth) acrylic acid derivative having a hydroxyl group. Of these, epoxy (meth) acrylate is more preferable. The (meth) acrylic compound preferably has two or more (meth) acryloyl groups in the molecule because of its high reactivity.

Examples of the monofunctional compounds among the (meth) acrylic acid ester compounds include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, and 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, iso Myristyl (meth) acrylate, stearyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxy Til (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, bicyclopentenyl (meth) acrylate, benzyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2 -Butoxyethyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, methoxyethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, tetrahydrofur Furyl (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, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, 2- (meth) acryloyloxyethyl 2-hydroxypropyl phthalate, 2- (meth) acrylic Examples include leuoxyethyl phosphate and glycidyl (meth) acrylate.

Examples of the bifunctional compound among the (meth) acrylic acid ester compounds include 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, and 1,6-hexane. Diol 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, poly Lopylene glycol di (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 isocyanuric acid 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 (Meth) acrylate.

Further, among the above (meth) acrylic acid ester compounds, those having three or more functions include, for example, 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, dipentaerythritol hexa (meth) acrylate.

Examples of the epoxy (meth) acrylate include those obtained by reacting an epoxy compound and (meth) acrylic acid in the presence of a basic catalyst according to a conventional method.

As an epoxy compound used as a raw material for synthesize | combining the said epoxy (meth) acrylate, the thing similar to what was mentioned as curable resin which has the said epoxy group, etc. can be used.

Examples of commercially available epoxy (meth) acrylates include, for example, EBECRYL860, EBECRYL3200, EBECRYL3201, EBECRYL3412, EBECRYL3600, EBECRYL3700, EBECRYL3701, EBECRYL3702, EBECRYL3703, EBECRY3603 EA-1010, EA-1020, EA-5323, EA-5520, EA-CHD, EMA-1020 (all manufactured by Shin-Nakamura Chemical Co., Ltd.), 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 (all manufactured by Kyoeisha Chemical Co., Ltd.), Denacol acrylate DA-141, Denacol acrylate DA-314, Denacol acrylate DA-911 (all manufactured by Nagase ChemteX Corporation).

The urethane (meth) acrylate obtained by reacting the above-mentioned isocyanate compound with a (meth) acrylic acid derivative having a hydroxyl group is, for example, (meth) acrylic acid having a hydroxyl group with respect to 1 equivalent of an isocyanate compound having two isocyanate groups. Two equivalents of the derivative can be obtained by reacting in the presence of a catalytic amount of a tin-based compound.

Examples of the isocyanate compound used as the raw material for the urethane (meth) acrylate include isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and diphenylmethane-4,4. '-Diisocyanate (MDI), hydrogenated MDI, polymeric MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate, tolidine diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, tris (isocyanate) Phenyl) thiophosphate, tetramethylxylylene diisocyanate, 1,6,11-undecantrie Cyanate, and the like.

Examples of the isocyanate compound that is a raw material for the urethane (meth) acrylate include, for example, polyols such as ethylene glycol, propylene glycol, glycerin, sorbitol, trimethylolpropane, carbonate diol, polyether diol, polyester diol, and polycaprolactone diol. Chain-extended isocyanate compounds obtained by reaction with excess isocyanate compounds can also be used.

Examples of the (meth) acrylic acid derivative having a hydroxyl group as a raw material for the urethane (meth) acrylate include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth). Hydroxyalkyl mono (meth) acrylates such as acrylate, 4-hydroxybutyl (meth) acrylate, ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol Mono (meth) acrylates of dihydric alcohols such as mono (meth) acrylates or di (meth) acrylates of trivalent alcohols such as trimethylolethane, trimethylolpropane and glycerin, and bisphenol A type epoxy Epoxy (meth) acrylates such as acrylate and the like.

Examples of commercially available urethane (meth) acrylates include M-1100, M-1200, M-1210, M-1600 (all manufactured by Toagosei Co., Ltd.), EBECRYL210, EBECRYL220, EBECRYL230, EBECRYL270, EBECRYL1290, EBECRYL2220, EBECRYL4827, EBECRYL4842, EBECRYL4858, EBECRYL5129, EBECRYL6700, EBECRYL8402, EBECRYL8803, EBECRYL8804, EBECRYL8804 , Art resin N-1255, Art Resin UN-3320HB, Art Resin UN-7100, Art Resin UN-9000A, Art Resin UN-9000H (all manufactured by Negami Industrial Co., Ltd.), 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 (all Shin-Nakamura Chemical Industries AH-600, AI-600, AT-600, UA-101I, UA-101T, UA-306H, A-306I, UA-306T (all manufactured by Kyoeisha Chemical Co., Ltd.).

When the curable resin contains the partial (meth) acryl-modified epoxy resin or the (meth) acrylic compound, the ratio of the epoxy group to the (meth) acryloyl group in the curable resin is 30:70 to 95: 5 is preferable. When the ratio of the epoxy group to the (meth) acryloyl group is within this range, the adhesive property of the obtained liquid crystal display element sealant and the display performance of the liquid crystal display element using the obtained liquid crystal display element sealant are improved. Can be improved.

The curable resin preferably has a hydrogen bonding unit such as —OH group, —NH— group, and —NH ₂ group from the viewpoint of suppressing liquid crystal contamination.

The sealing agent for liquid crystal display elements of the present invention may contain a radical polymerization initiator.
As the radical polymerization initiator, a thermal radical polymerization initiator or a photo radical polymerization initiator can be used.

As said thermal radical polymerization initiator, what consists of an azo compound, an organic peroxide, etc. is mentioned, for example. Among them, from the viewpoint of suppressing liquid crystal contamination, an initiator composed of an azo compound (hereinafter also referred to as “azo initiator”) is preferable, and an initiator composed of a polymer azo compound (hereinafter referred to as “polymer azo initiator”). More preferred).
In the present specification, the “polymer azo compound” means a compound having an azo group and generating a radical capable of curing a (meth) acryloyl group by heat and having a number average molecular weight of 300 or more. To do.

The preferable lower limit of the number average molecular weight of the polymeric azo initiator is 1000, and the preferable upper limit is 300,000. Liquid crystal contamination can be suppressed because the number average molecular weight of the said polymeric azo initiator is 1000 or more. When the number average molecular weight of the polymeric azo initiator is within this range, it can be more easily mixed into the curable resin while preventing adverse effects on the liquid crystal. The more preferable lower limit of the number average molecular weight of the polymeric azo initiator is 5000, the more preferable upper limit is 100,000, the still more preferable lower limit is 10,000, and the still more preferable upper limit is 90,000.
In addition, in this specification, the said number average molecular weight is a value calculated | required by polystyrene conversion by measuring with gel permeation chromatography (GPC). Examples of the column for measuring the number average molecular weight in terms of polystyrene by GPC include Shodex LF-804 (manufactured by Showa Denko KK).

Examples of the polymer azo initiator include those having a structure in which a plurality of units such as polyalkylene oxide and polydimethylsiloxane are bonded via an azo group.
As the polymer azo initiator having a structure in which a plurality of units such as polyalkylene oxide and polydimethylsiloxane are bonded via the azo group, those having a polyethylene oxide structure are preferable. Examples of such a polymer azo initiator include polycondensates of 4,4′-azobis (4-cyanopentanoic acid) and polyalkylene glycol, and 4,4′-azobis (4-cyanopentanoic acid) Examples thereof include polycondensates of polydimethylsiloxane having a terminal amino group, such as VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS-1001 (all of which are Wako Pure Chemical Industries, Ltd.) Manufactured) and the like.
Examples of the azo initiator other than the polymer azo initiator include V-65 and V-501 (both manufactured by Wako Pure Chemical Industries, Ltd.).

Examples of the organic peroxide include ketone peroxide, peroxyketal, hydroperoxide, dialkyl peroxide, peroxyester, diacyl peroxide, and peroxydicarbonate.

The content of the thermal radical polymerization initiator is preferably 0.05 parts by weight and preferably 10 parts by weight with respect to 100 parts by weight of the curable resin. When the content of the thermal radical polymerization initiator is 0.05 parts by weight or more, the obtained sealing agent for liquid crystal display elements is more excellent in thermosetting. When the content of the thermal radical polymerization initiator is 10 parts by weight or less, the obtained sealing agent for liquid crystal display elements is more excellent in the effect of suppressing liquid crystal contamination. The minimum with more preferable content of the said thermal radical polymerization initiator is 0.1 weight part, and a more preferable upper limit is 5 weight part.

Examples of the photo radical polymerization initiator include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, benzyl, thioxanthone, and the like.

Examples of commercially available radical photopolymerization initiators include IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 2959, IRGACURE OXE01, IRGACURE OXE01, IRGACURE OXE02, Rusine FOXE02 Examples include methyl ether, benzoin ethyl ether, and benzoin isopropyl ether (all manufactured by Tokyo Chemical Industry Co., Ltd.).

The content of the photo radical polymerization initiator is preferably 0.1 parts by weight and preferably 10 parts by weight with respect to 100 parts by weight of the curable resin. When the content of the radical photopolymerization initiator is 0.1 parts by weight or more, the obtained sealing agent for liquid crystal display elements is more excellent in photocurability. When the content of the radical photopolymerization initiator is 10 parts by weight or less, the obtained sealing agent for liquid crystal display elements is more excellent in weather resistance. The minimum with more preferable content of the said radical photopolymerization initiator is 0.2 weight part, and a more preferable upper limit is 8 weight part. *

The sealing agent for liquid crystal display elements of the present invention may contain a filler for the purpose of improving the viscosity, improving the adhesiveness due to the stress dispersion effect, improving the linear expansion coefficient, and further improving the moisture resistance of the cured product. Good.

Examples of the filler include talc, asbestos, silica, diatomaceous earth, smectite, bentonite, calcium carbonate, magnesium carbonate, alumina, montmorillonite, zinc oxide, iron oxide, magnesium oxide, tin oxide, titanium oxide, magnesium hydroxide, water Inorganic fillers such as aluminum oxide, glass beads, silicon nitride, barium sulfate, gypsum, calcium silicate, sericite, activated clay, aluminum nitride, polyester fine particles, polyurethane fine particles, vinyl polymer fine particles, acrylic polymer fine particles, core shell acrylate Examples include organic fillers such as copolymer fine particles. These fillers may be used alone or in combination of two or more.

The preferable lower limit of the content of the filler in 100 parts by weight of the sealant for liquid crystal display elements of the present invention is 10 parts by weight, and the preferable upper limit is 70 parts by weight. When the content of the filler is 10 parts by weight or more, effects such as improvement in adhesiveness can be further enhanced. When the content of the filler is 70 parts by weight or less, the obtained sealing agent for liquid crystal display elements is more excellent in applicability. The minimum with more preferable content of the said filler is 20 weight part, and a more preferable upper limit is 60 weight part.

The sealing agent for liquid crystal display elements of the present invention may contain a silane coupling agent. The silane coupling agent mainly has a role as an adhesion assistant for favorably bonding the sealing agent and the substrate.
As said silane coupling agent, since it is excellent in the effect which improves adhesiveness with a board | substrate etc. and it can suppress the outflow of curable resin in a liquid crystal by chemically bonding with curable resin, it is N, for example. -Phenyl-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-isocyanatopropyltrimethoxysilane, etc. are preferably used . These silane coupling agents may be used alone or in combination of two or more.

The minimum with preferable content of the said silane coupling agent in 100 weight part of sealing agents for liquid crystal display elements of this invention is 0.1 weight part, and a preferable upper limit is 20 weight part. Adhesiveness with a board | substrate etc. can be improved more because content of the said silane coupling agent is 0.1 weight part or more. When the content of the silane coupling agent is 20 parts by weight or less, the obtained sealing agent for liquid crystal display elements is more excellent in the effect of suppressing liquid crystal contamination. The minimum with more preferable content of the said silane coupling agent is 0.5 weight part, and a more preferable upper limit is 10 weight part.

The sealing agent for liquid crystal display elements of the present invention further comprises a reactive diluent for adjusting the viscosity, a spacer such as polymer beads for adjusting the panel gap, 3-P-chlorophenyl-1,1- You may contain additives, such as hardening accelerators, such as a dimethyl urea and isocyanuric carboxylic acid, an antifoamer, a leveling agent, a polymerization inhibitor, and another coupling agent.

As a method for producing the sealing agent for liquid crystal display elements of the present invention, for example, using a mixer such as a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, or a three roll, a curable resin and a heat Examples include a method of mixing a curing agent with an additive such as a filler or a silane coupling agent added as necessary.

A vertical conduction material can be produced by blending conductive fine particles with the sealing agent for liquid crystal display elements of the present invention. Such a vertical conduction material containing the sealing agent for liquid crystal display elements of the present invention and conductive fine particles is also one aspect of the present invention.

The conductive fine particles are not particularly limited, and metal balls, those obtained by forming a conductive metal layer on the surface of resin fine particles, and the like can be used. Among them, the one in which the conductive metal layer is formed on the surface of the resin fine particles is preferable because the conductive connection is possible without damaging the transparent substrate due to the excellent elasticity of the resin fine particles.

The liquid crystal display element using the sealing agent for liquid crystal display elements of this invention or the vertical conduction material of this invention is also one of this invention.
As a method for producing the liquid crystal display element of the present invention, a liquid crystal dropping method is preferably used. Specifically, for example, a step of forming a frame-shaped seal pattern on one of two transparent substrates having electrodes such as an ITO thin film by screen printing, dispenser application, etc. of the liquid crystal display element of the present invention, liquid crystal And applying the microdroplets to the entire surface of the seal pattern frame, overlaying the other substrate under vacuum, and irradiating the seal pattern portion with light such as ultraviolet rays to temporarily cure the sealant, and The method etc. which have the process of heating and hardening | curing the sealing agent temporarily hardened are mentioned.

ADVANTAGE OF THE INVENTION According to this invention, the sealing compound for liquid crystal display elements which can make low-temperature curability and storage stability compatible can be provided. Moreover, according to this invention, the vertical conduction material and liquid crystal display element which use this sealing compound for liquid crystal display elements can be provided.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

(Production of amine adduct compound A)
300 mL of a mixed solution of n-butanol / toluene having a mixing ratio of 1: 1 was put into a three-necked flask, and further 38.0 parts by weight of bisphenol A type epoxy resin (Mitsubishi Chemical Co., Ltd., “jER828”) and 2-methylimidazole (Tokyo Kasei). Kogyo Co., Ltd.) 4.1 parts by weight were charged. After stirring with heating at 65 ° C. for 4 hours, solvent removal and vacuum drying were performed to obtain amine adduct compound A having a structure derived from bisphenol A type epoxy resin and a structure derived from 2-methylimidazole.
The obtained amine adduct compound A was confirmed to be a compound represented by the above formula (2-1) by performing ¹ H-NMR, ¹³ C-NMR, and IR measurement.

(Production of amine adduct compound B)
300 mL of a mixed solution of n-butanol / toluene having a mixing ratio of 1: 1 was put into a three-necked flask, and further 30.0 parts by weight of an aliphatic epoxy resin (“YH-300” manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) and 2-methylimidazole ( 4.1 parts by weight of Tokyo Chemical Industry Co., Ltd. was charged. After stirring for 4 hours at 65 ° C., solvent removal and vacuum drying were performed to obtain amine adduct compound B having a structure derived from an aliphatic epoxy resin and a structure derived from 2-methylimidazole.
The obtained amine adduct compound B was confirmed to be a compound represented by the above formula (2-2) by ¹ H-NMR, ¹³ C-NMR, and IR measurements.

(Production of amine adduct compound C)
300 ml of a mixed solution of n-butanol / toluene with a mixing ratio of 1: 1 was put into a three-necked flask, and further 38.0 parts by weight of a bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation, “jER828”) and 2-heptadecylimidazole (Shikoku) 20.3 parts by weight of “C17Z” manufactured by Kasei Kogyo Co., Ltd. was added. After stirring for 4 hours at 65 ° C., solvent removal and vacuum drying were performed to obtain an amine adduct compound C having a structure derived from a bisphenol A type epoxy resin and a structure derived from 2-heptadecylimidazole.
The obtained amine adduct compound C was confirmed to be a compound represented by the above formula (2-3) by ¹ H-NMR, ¹³ C-NMR, and IR measurement.

(Production of amine adduct compound D)
300 mL of a mixed solution of n-butanol / toluene with a mixing ratio of 1: 1 is put into a three-necked flask, and further 30.0 parts by weight of an aliphatic epoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., “YH-300”) and 2-heptadecylimidazole 20.3 parts by weight (“C17Z” manufactured by Shikoku Kasei Kogyo Co., Ltd.) was added. After stirring for 4 hours at 65 ° C., solvent removal and vacuum drying were performed to obtain an amine adduct compound D having a structure derived from an aliphatic epoxy resin and a structure derived from 2-heptadecylimidazole.
The obtained amine adduct compound D was confirmed to be a compound represented by the above formula (2-4) by ¹ H-NMR, ¹³ C-NMR and IR measurements.

(Production of amine adduct compound E)
300 mL of a mixed solution of n-butanol / toluene having a mixing ratio of 1: 1 was put into a three-necked flask, and further 38.0 parts by weight of a bisphenol A type epoxy resin (Mitsubishi Chemical Co., Ltd., “jER828”) and 2-phenylimidazole (Wako Pure) 7.2 parts by weight of Yakuhin Kogyo Co., Ltd. was charged. After stirring for 4 hours at 65 ° C., solvent removal and vacuum drying were performed to obtain an amine adduct compound E having a structure derived from a bisphenol A type epoxy resin and a structure derived from 2-phenylimidazole.
The obtained amine adduct compound E was confirmed to be a compound represented by the following formula (3) by performing ¹ H-NMR, ¹³ C-NMR, and IR measurement.

(Examples 1 to 7, Comparative Examples 1 to 4)
According to the blending ratio described in Table 1, each material was mixed using a planetary stirrer (“Shinky Co., Ltd.,“ Awatori Nertaro ”), and then mixed using three rolls. The sealing agents for liquid crystal display elements 1 to 7 and Comparative Examples 1 to 4 were prepared.

<Evaluation>
The following evaluation was performed about each sealing compound for liquid crystal display elements obtained by the Example and the comparative example. The results are shown in Table 1.

(Storage stability)
About each liquid crystal display element sealing agent obtained in Examples and Comparative Examples, the initial viscosity immediately after production and the viscosity when stored at 25 ° C. for 3 days were measured, and the viscosity after storage at 25 ° C. for 3 days was measured. ) / (Initial viscosity) is the rate of change in viscosity, the rate of change in viscosity was less than 1.3, “◎”, the rate of 1.3 or more and less than 1.5 being “◯”, 1.5 or more The storage stability was evaluated as “△” when it was less than 2.0, and “×” when it was 2.0 or more.
The viscosity of the sealing agent was measured using an E-type viscometer (manufactured by BROOK FIELD, “DV-III”) at 25 ° C. and a rotation speed of 1.0 rpm.

(Low temperature curability)
Each liquid crystal display element sealant obtained in Examples and Comparative Examples was filled in a dispensing syringe (“PSY-10E” manufactured by Musashi Engineering Co., Ltd.) and subjected to defoaming treatment. Next, a sealant was applied so as to draw a rectangular frame on one of two transparent electrode substrates with an ITO thin film using a dispenser (manufactured by Musashi Engineering, “SHOTMASTER300”). Subsequently, fine droplets of TN liquid crystal (manufactured by Chisso, “JC-5001LA”) are dropped on the formed sealant frame with a liquid crystal dropping device, and the other transparent substrate is placed at 5 Pa with a vacuum bonding device. Were bonded together under reduced pressure. The cell after bonding was irradiated with 3000 mJ / cm ² of ultraviolet rays with a metal halide lamp, and then the sealing agent was thermally cured by heating at 100 ° C. for 60 minutes, thereby producing a liquid crystal display element. Irradiation with ultraviolet rays was performed by cutting light having a wavelength of 340 nm or less with a filter. The obtained liquid crystal display element was stored at a temperature of 80 ° C. for 100 hours, and then was driven with a voltage of AC 3.5 V and visually observed. “◎” indicates no display unevenness (color unevenness) at the periphery of the liquid crystal display element, “○” indicates a slight display unevenness, and “o” indicates a clear dark display unevenness. “Δ”, the display performance of the liquid crystal display element was evaluated with “×” when the clear dark display unevenness spread not only in the peripheral part but also in the central part.

(Visible light curable)
Each liquid crystal display element sealant obtained in Example 5 was coated on a glass substrate by about 5 μm, and a glass substrate of the same size was superposed on the substrate, and then light of 100 mW / cm ² using a metal halide lamp. Was irradiated for 10 seconds. Light irradiation was performed by cutting light having a wavelength of 380 nm or less with a filter. The peak derived from the acryloyl group before and after the light irradiation was measured using an infrared spectroscope (manufactured by BIORAD, “FTS3000”), and the reduction rate of the peak derived from the acryloyl group after the light irradiation was derived. When the rate of decrease in the peak derived from the acryloyl group after light irradiation is 93% or more, “「 ”, when it is 85% or more and less than 93%,“ ◯ ”, when it is 75% or more and less than 85% Visible light curability was evaluated as “Δ”, where “×” was less than 75%.

ADVANTAGE OF THE INVENTION According to this invention, the sealing compound for liquid crystal display elements which can make low-temperature curability and storage stability compatible can be provided. Moreover, the vertical conduction material and liquid crystal display element which use this sealing compound for liquid crystal display elements can be provided.

Claims (7)

1. A sealing agent for a liquid crystal display element containing a curable resin and a thermosetting agent,
   The curable resin contains a curable resin having an epoxy group,
   The thermosetting agent contains an amine adduct compound having a structure derived from an epoxy resin and a structure derived from an amine compound,
   A sealing agent for a liquid crystal display device, wherein the amine compound from which the amine adduct compound is derived is an alkyl imidazole having an alkyl group having 1 to 20 carbon atoms.
2. 2. The sealant for a liquid crystal display element according to claim 1, wherein the alkylimidazole having 1 to 20 carbon atoms in the alkyl group is 2-methylimidazole.
3. 3. The sealing agent for liquid crystal display elements according to claim 1, wherein the epoxy resin from which the amine adduct compound is derived has an aromatic ring.
4. The epoxy resin from which the amine adduct compound is derived is at least one selected from the group consisting of a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and a bisphenol E type epoxy resin. The sealing agent for liquid crystal display elements of 2 or 3.
5. A sealing agent for a liquid crystal display element containing a curable resin and a thermosetting agent,
   The curable resin contains a curable resin having an epoxy group, and the thermosetting agent is a compound represented by the following formula (1-1) and / or a compound represented by the following formula (1-2): A sealing agent for liquid crystal display elements, comprising:
   

   

   In Formula (1-1) and Formula (1-2), R ¹ is an alkyl group having 1 to 20 carbon atoms. In Formula (1-1), R ² and R ³ are hydrogen or methyl. Each group may be the same or different.
6. A vertical conduction material comprising the liquid crystal display element sealant according to claim 1, and conductive fine particles.
7. A liquid crystal display element comprising the sealant for a liquid crystal display element according to claim 1, 2, 3, 4, or 5, or the vertical conduction material according to claim 6.