JP6978311B2 - Sealing agent for liquid crystal display element, vertical conduction material, and liquid crystal display element - Google Patents

Description

The present invention relates to a sealant for a liquid crystal display element, which has excellent adhesiveness and can suppress liquid crystal contamination. The present invention also relates to a vertically conductive material and a liquid crystal display element using the sealant for a liquid crystal display element.

In recent years, as a method for manufacturing a liquid crystal display element, a curable resin, a photopolymerization initiator, and heat as disclosed in Patent Document 1 and Patent Document 2 are used from the viewpoint of shortening the tact time and optimizing the amount of liquid crystal used. A liquid crystal dropping method called a dropping method using a curing type sealant containing a curing agent and a photothermal combination is used.

In the dropping method, first, a rectangular seal pattern is formed on one of the two transparent substrates with electrodes by dispensing. Next, in a state where the sealant is uncured, fine droplets of liquid crystal are dropped on the entire surface of the frame of the transparent substrate, the other transparent substrate is immediately overlapped, and the seal portion is irradiated with light such as ultraviolet rays to perform temporary curing. .. Then, it is heated to perform the main curing, and a liquid crystal display element is manufactured. A liquid crystal display element can be manufactured with extremely high efficiency by bonding the substrates under reduced pressure, and this dropping method is currently the mainstream method for manufacturing a liquid crystal display element.

By the way, in the present age when various mobile devices with liquid crystal panels such as mobile phones and portable game machines are widespread, miniaturization of the devices is the most sought after issue. As a method for reducing the size of the device, a narrowing of the frame of the liquid crystal display unit is mentioned. For example, the position of the seal portion is arranged under the black matrix (hereinafter, also referred to as a narrow frame design).
However, in the narrow frame design, the sealant is placed directly under the black matrix, so if the dropping method is used, the light emitted when the sealant is photocured is blocked and the light does not reach the inside of the sealant. There was a problem that the curing was insufficient. When the sealant is not sufficiently cured in this way, the uncured sealant component is eluted in the liquid crystal display, and the curing reaction by the eluted sealant component proceeds in the liquid crystal display, resulting in liquid crystal contamination. there were.

Japanese Unexamined Patent Publication No. 2001-133794 International Publication No. 02/092718

An object of the present invention is to provide a sealant for a liquid crystal display element, which has excellent adhesiveness and can suppress liquid crystal contamination. Another object of the present invention is to provide a vertically conductive material and a liquid crystal display element using the sealant for a liquid crystal display element.

The present invention contains a curable resin containing a compound represented by the following formula (1) and a thermosetting agent .
A sealant for a liquid crystal display element having a content of the compound represented by the formula (1) of 1% by weight or more and less than 30% by weight.

In the formula (1), l, m, and n are 0 to 6, respectively, and Y is 1 to 20.
The present invention will be described in detail below.

The present inventor has studied the use of bisphenol S diglycidyl ether, which has excellent adhesiveness and low liquid crystal contamination, as a curable resin to be blended in a sealant for a liquid crystal display element. However, even when bisphenol S diglycidyl ether was used, the effect of suppressing adhesiveness and liquid crystal contamination was not sufficient.
Therefore, as a result of further diligent studies, the present inventors can obtain a sealant for a liquid crystal display element having excellent adhesiveness and suppressing liquid crystal contamination by using a bisphenol S type epoxy resin having a specific structure. And came to complete the present invention.

The sealant for a liquid crystal display element of the present invention contains a curable resin.
The curable resin contains a compound represented by the above formula (1). By containing the compound represented by the above formula (1), the sealant for a liquid crystal display element of the present invention is excellent in adhesiveness and the effect of suppressing liquid crystal contamination.

In the above formula (1), l, m, and n are 0 to 6, respectively. The above l, m, and n are preferably 1 to 6, respectively, and more preferably 1 to 3 respectively.
Further, in the above formula (1), Y is 1 to 20. The Y is preferably 1 to 10, and more preferably 1 to 4.
The values of l, m, n, and Y in the above formula (1) are average values. Further, the case where l, m or n is 0 means that the ethylene oxide structural portion to which l, m or n is attached serves as a bond.

Examples of the method for producing the compound represented by the above formula (1) include a method of conducting a condensation polymerization reaction between bisphenol S or ethylene oxide-modified bisphenol S and epichlorohydrin.

The content of the compound represented by the above formula (1) in the sealant for a liquid crystal display element of the present invention is preferably 1% by weight or more and less than 30% by weight. When the content of the compound represented by the above formula (1) is within this range, the obtained sealant for a liquid crystal display element suppresses adhesiveness and liquid crystal contamination without deteriorating the coatability and moisture permeation prevention property. The effect will be better. The more preferable lower limit of the content of the compound represented by the above formula (1) is 5% by weight, the more preferable upper limit is 25% by weight, the further preferable lower limit is 10% by weight, and the further preferable upper limit is 20% by weight.

The curable resin preferably contains other curable resin in addition to the compound represented by the above formula (1).
Examples of the other curable resin include (meth) acrylic compounds and epoxy compounds other than the compounds represented by the above formula (1).

The (meth) acrylic compound is, for example, an epoxy (meth) acrylate obtained by reacting (meth) acrylic acid with an epoxy compound, or obtained by reacting (meth) acrylic acid with a compound having a hydroxyl group. Examples thereof include a (meth) acrylic acid ester compound and a urethane (meth) acrylate obtained by reacting an isocyanate compound with a (meth) acrylic acid derivative having a hydroxyl group. Of these, epoxy (meth) acrylate is preferable. Further, the (meth) acrylic compound preferably has two or more (meth) acryloyl groups in the molecule due to its high reactivity.
In the present specification, the above-mentioned "(meth) acrylate" means acrylate or methacrylate, and "epoxy (meth) acrylate" means that all epoxy groups in the epoxy compound are reacted with (meth) acrylic acid. Represents a compound.

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.

Examples of the epoxy compound used as a raw material for synthesizing the above epoxy (meth) acrylate include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, and 2,2'-. Dialyl bisphenol A type epoxy resin, hydrogenated 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 phenol novolac type epoxy resin, glycidylamine type epoxy resin, alkyl polyol type epoxy resin , Rubber-modified epoxy resin, glycidyl ester compound and the like.

Examples of commercially available bisphenol A type epoxy resins include jER828EL, jER1004 (all manufactured by Mitsubishi Chemical Corporation), Epicron 850CRP (manufactured by DIC Corporation), and the like.
Examples of commercially available bisphenol F-type epoxy resins include jER806 and jER4004 (both manufactured by Mitsubishi Chemical Corporation).
Examples of commercially available bisphenol E-type epoxy resins include R710 (manufactured by Printec).
Examples of commercially available bisphenol S-type epoxy resins include Epicron EXA1514 (manufactured by DIC Corporation).
Examples of commercially available 2,2'-diallyl bisphenol A type epoxy resins include RE-810NM (manufactured by Nippon Kayaku Co., Ltd.).
Examples of commercially available hydrogenated bisphenol type epoxy resins include Epicron EXA7015 (manufactured by DIC Corporation).
Examples of commercially available propylene oxide-added bisphenol A type epoxy resins include EP-4000S (manufactured by ADEKA Corporation) and the like.
Examples of commercially available resorcinol-type epoxy resins include EX-201 (manufactured by Nagase ChemteX Corporation) and the like.
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 & Sumitomo Metal Corporation).
Examples of commercially available diphenyl ether type epoxy resins include YSLV-80DE (manufactured by Nippon Steel & Sumitomo Metal Corporation).
Examples of commercially available dicyclopentadiene type epoxy resins include EP-4088S (manufactured by ADEKA Corporation) and the like.
Examples of commercially available naphthalene-type epoxy resins include Epicron HP4032 and Epicron EXA-4700 (both manufactured by DIC Corporation).
Examples of commercially available phenol novolac type epoxy resins include Epicron N-770 (manufactured by DIC Corporation).
Examples of commercially available orthocresol novolak type epoxy resins include Epicron N-670-EXP-S (manufactured by DIC Corporation).
Examples of commercially available dicyclopentadiene novolak type epoxy resins include Epicron HP7200 (manufactured by DIC Corporation).
Examples of commercially available biphenyl novolac type epoxy resins include NC-3000P (manufactured by Nippon Kayaku Co., Ltd.) and the like.
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 Corporation), Epicron 430 (manufactured by DIC Corporation), TETRAD-X (manufactured by Mitsubishi Gas Chemical Corporation), and the like.
Among the above-mentioned alkyl polyol type epoxy resins, those commercially available include, for example, ZX-1542 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), Epicron 726 (manufactured by DIC Corporation), Epolite 80MFA (manufactured by Kyoeisha Chemical Co., Ltd.), and Denacol EX-611. (Manufactured by Nagase ChemteX) and the like.
Examples of commercially available rubber-modified epoxy resins include YR-450, YR-207 (all manufactured by Nippon Steel & Sumitomo Metal Corporation), 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) and the like.
Other commercially available epoxy compounds include, for example, YDC-1312, YSLV-80XY, YSLV-90CR (all manufactured by Nissan Chemical Industries, Ltd.), XAC4151 (manufactured by Asahi Kasei Corporation), jER1031, and jER1032 (all of which are manufactured by Asahi Kasei Corporation). (Made by Mitsubishi Chemical Corporation), EXA-7120 (manufactured by DIC Corporation), TEPIC (manufactured by Nissan Chemical Industries, Ltd.) and the like.

Among the above-mentioned epoxy (meth) acrylates, commercially available ones include, for example, EBECRYL860, EBECRYL3200, EBECRYL3201, EBECRYL3412, EBECRYL3600, EBECRYL3700, EBECRYL3701, EBECRYL3702, EBECRYL3702, EBECRYL370 EA-1010, EA-1020, EA-5323, EA-5520, EA-CHD, EMA-1020 (all manufactured by Shin-Nakamura Chemical Industry 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, Ester 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) and the like can be mentioned.

Among the above (meth) acrylic acid ester compounds, monofunctional ones 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-hydroxybutyl (meth) acrylate, cyclohexyl ( Meta) acrylate, isobornyl (meth) acrylate, bicyclopentenyl (meth) acrylate, benzyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, 2-Phenoxyethyl (meth) acrylate, methoxyethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, ethylcarbi Thor (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, 1H, 1H, 5H-octafluoropentyl (meth) acrylate, Imid (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, 2- ( Examples thereof include 2- (meth) acryloyloxyethyl phosphate, 2- (meth) acryloyloxyethyl phosphate, and glycidyl (meth) acrylate.

Among the above (meth) acrylic acid ester compounds, bifunctional ones include, for example, 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, and 1,6-hexane. Didiol di (meth) acrylate, 1,9-nonane diol di (meth) acrylate, 1,10-decane diol di (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (Meta) 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 ) Acrylate, polypropylene 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 dicyclopentadienyldi (meth) acrylate, ethylene oxide modified isocyanuric acid di (meth) acrylate, 2-hydroxy-3- (meth) acryloyloxypropyl (meth) acrylate, carbonate diol di (meth) acrylate, Examples thereof include polyether diol di (meth) acrylate, polyester diol di (meth) acrylate, polycaprolactone diol di (meth) acrylate, and polybutadiene diol di (meth) acrylate.

Among the above (meth) acrylic acid ester compounds, those having trifunctionality or higher include, for example, trimethylol propanetri (meth) acrylate, ethylene oxide-added trimethylol propanetri (meth) acrylate, and propylene oxide-added trimethylol propanetri (meth) acrylate. Meta) acrylate, ethylene oxide-added isocyanuric acid tri (meth) acrylate, glycerintri (meth) acrylate, propylene oxide-added glycerintri (meth) acrylate, pentaerythritol tri (meth) acrylate, tris (meth) acryloyloxyethyl phosphate, ditri Examples thereof include methylolpropanetetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate.

As the urethane (meth) acrylate, for example, by reacting 2 equivalents of a (meth) acrylic acid derivative having a hydroxyl group with 1 equivalent of an isocyanate compound having two isocyanate groups in the presence of a catalytic amount of a tin-based compound. Obtainable.

Examples of the isocyanate compound used as a 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, polypeptide MDI, 1,5-naphthalenediocyanate, norbornan diisocyanate, trizine diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, tris (isocyanate) Examples thereof include phenyl) thiophosphate, tetramethylxylene diisocyanate, 1,6,11-undecantry isocyanate and the like.

The isocyanate compound used as a raw material for the urethane (meth) acrylate includes, 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, which is a raw material of the urethane (meth) acrylate, include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth). Hydroxyalkyl (meth) acrylates such as acrylates and 4-hydroxybutyl (meth) acrylates, ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol and the like. Divalent alcohol mono (meth) acrylate, trivalent alcohol mono (meth) acrylate or di (meth) acrylate such as trimethylol ethane, trimethylol propane, glycerin, and epoxy such as bisphenol A type epoxy acrylate. Examples thereof include (meth) acrylate.

Commercially available urethane (meth) acrylates include, for example, M-1100, M-1200, M-1210, M-1600 (all manufactured by Toa Synthetic Co., Ltd.), EBECRYL210, EBECRYL220, EBECRYL230, EBECRYL270. EBECRYL1290, EBECRYL2220, EBECRYL4827, EBECRYL4842, EBECRYL4858, EBECRYL5129, EBECRYL6700, EBECRYL8402, EBECRYL8803, EBECRYL8803, EBECRYL8804, EBECRYL8804 , Art Resin UN-1255, Art Resin UN-3320HB, Art Resin UN-7100, Art Resin UN-9000A, Art Resin UN-9000H (all manufactured by Negami Kogyo 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 new Nakamura Chemical Industry Co., Ltd.), AH-600, AI-600, AT-600, UA-101I, UA-101T, UA-306H, UA-306I, UA-306T (all manufactured by Kyoeisha Chemical Co., Ltd.) and the like. ..

Examples of the epoxy compound which is the other curable resin include an epoxy compound which is a raw material for synthesizing the epoxy (meth) acrylate other than the compound represented by the formula (1), and a portion (meth). Acrylic modified epoxy resin and the like can be mentioned.
In addition, in this specification, the said partial (meth) acrylic modified epoxy resin means a compound which has one or more epoxy groups and (meth) acryloyl groups in one molecule, for example, two in one molecule. It can be obtained by reacting the epoxy group of a part of the epoxy compound having the above epoxy group with (meth) acrylic acid.

Among the above-mentioned partial (meth) acrylic-modified epoxy resins, commercially available ones include, for example, UVACURE1561 (manufactured by Dycel Ornex) and the like.

When the other curable resin is contained, the preferable lower limit of the content of the compound represented by the above formula (1) in 100 parts by weight of the entire curable resin is 5 parts by weight, and the preferable upper limit is 25 parts by weight. When the content of the compound represented by the above formula (1) is within this range, the obtained sealant for a liquid crystal display element has an effect of suppressing coating property, adhesiveness, moisture permeation prevention property, and liquid crystal contamination. Will be better. The more preferable lower limit of the content of the compound represented by the above formula (1) is 10 parts by weight, and the more preferable upper limit is 20 parts by weight.

When the curable resin contains the (meth) acrylic compound or the partial (meth) acrylic-modified epoxy resin, the content ratio of the (meth) acryloyl group and the epoxy group in the curable resin is 50:50 in molar ratio. It is preferably ~ 95: 5.

The sealant for a liquid crystal display element of the present invention contains a thermosetting agent.
From the viewpoint of reactivity, the thermosetting agent preferably contains a trifunctional or higher functional thermosetting agent.
The above-mentioned "three-functional or higher thermosetting agent" means a thermosetting agent composed of a compound having three or more functional groups in one molecule that are activated by heating and act on the curing reaction of the curable resin.

Examples of the trifunctional or higher thermosetting agent include citric acid trihydrazide, cyclohexanetricarboxylic acid trihydrazide, 1,3,5-tris (2-carboxyethyl) isocyanurate and the like.

Examples of the other heat-curing agents include organic acid dihydrazide, imidazole derivative, amine compound, polyhydric phenolic compound, acid anhydride and the like. Of these, organic acid dihydrazide is preferably used.

Examples of the organic acid dihydrazide include sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, and malonic acid dihydrazide.
Commercially available organic acid dihydrazides include, for example, SDH, ADH (all manufactured by Otsuka Chemical Co., Ltd.), Amicure VDH, Amicure VDH-J, Amicure UDH, and Ajinomoto Fine-Techno Co., Ltd. Made) and the like.

The content of the thermosetting agent is preferably 1 part by weight and a preferable upper limit of 50 parts by weight with respect to 100 parts by weight of the curable resin. When the content of the thermosetting agent is in this range, the thermosetting agent can be made more excellent in thermosetting without deteriorating the coatability of the obtained sealant for a liquid crystal display element. A more preferable upper limit of the content of the thermosetting agent is 30 parts by weight.

The sealant for a liquid crystal display element of the present invention may contain a radical polymerization initiator.
Examples of the radical polymerization initiator include a photoradical polymerization initiator that generates radicals by light irradiation, a thermal radical polymerization initiator that generates radicals by heating, and the like.

Examples of the photoradical polymerization initiator include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanosen compounds, oxime ester compounds, benzoin ether compounds, thioxanthone compounds and the like.

Commercially available photoradical polymerization initiators include, for example, IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACURE OXE01, and Lucyrin TPO. ), NCI-930 (manufactured by ADEKA), SPEEDCURE EMK (manufactured by Sebel Hegner, Japan), benzoine methyl ether, benzoin ethyl ether, benzoin isopropyl ether (all manufactured by Tokyo Kasei Kogyo Co., Ltd.) and the like.

Examples of the thermal radical polymerization initiator include those made of an azo compound, an organic peroxide and the like. Of these, an initiator composed of a polymer azo compound (hereinafter, also referred to as “polymer azo initiator”) is preferable.
In the present specification, the polymer azo compound means a compound having an azo group and having a number average molecular weight of 300 or more, which generates a radical capable of curing the (meth) acryloyl group by heat.

The preferred lower limit of the number average molecular weight of the polymer azo initiator is 1000, and the preferred upper limit is 300,000. When the number average molecular weight of the polymer azo initiator is in this range, it can be easily mixed with the curable resin while suppressing liquid crystal contamination. The more preferable lower limit of the number average molecular weight of the polymer azo initiator is 5000, the more preferable upper limit is 100,000, the further preferable lower limit is 10,000, and the further preferable upper limit is 90,000.
In the present specification, the number average molecular weight is a value obtained by measuring by gel permeation chromatography (GPC) and converting into polystyrene. 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) and the like.

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 are bonded via the azo group, those having a polyethylene oxide structure are preferable. Examples of such a polymer azo initiator include a polycondensate 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, and specific examples thereof include VPE-0201, VPE-0401, VPE-0601, VPS-0501, and VPS-1001 (all of which are Wako Pure Chemical Industries, Ltd.). Made) and the like.
Examples of non-polymer azo compounds include V-65 and V-501 (both manufactured by Wako Pure Chemical Industries, Ltd.).

Examples of the organic peroxide include ketone peroxides, peroxyketals, hydroperoxides, dialkyl peroxides, peroxyesters, diacyl peroxides, peroxydicarbonates and the like.

The content of the radical polymerization initiator has a preferable lower limit of 0.01 parts by weight and a preferable upper limit of 10 parts by weight with respect to 100 parts by weight of the curable resin. When the content of the radical polymerization initiator is in this range, the obtained sealant for a liquid crystal display element is excellent in storage stability and curability while suppressing liquid crystal contamination. The more preferable lower limit of the content of the radical polymerization initiator is 0.1 parts by weight, and the more preferable upper limit is 5 parts by weight.

The sealant for a liquid crystal display element of the present invention may contain a filler for the purpose of improving the viscosity, improving the adhesiveness by the stress dispersion effect, improving the linear expansion coefficient, improving the moisture permeation prevention property of the cured product, and the like. preferable.

Examples of the filler include silica, talc, glass beads, asbestos, gypsum, diatomaceous soil, smectite, bentonite, montmorillonite, sericite, active white clay, alumina, zinc oxide, iron oxide, magnesium oxide, tin oxide, titanium oxide, and the like. Inorganic fillers such as calcium carbonate, magnesium carbonate, magnesium hydroxide, aluminum hydroxide, aluminum nitride, silicon nitride, barium sulfate, calcium silicate, and organics such as polyester fine particles, polyurethane fine particles, vinyl polymer fine particles, acrylic polymer fine particles, etc. Examples include fillers.

The preferable lower limit of the content of the filler in the sealant for a liquid crystal display element of the present invention is 10% by weight, and the preferable upper limit is 70% by weight. When the content of the filler is in this range, the effect of improving the adhesiveness and the like is excellent without deteriorating the coatability and the like. The more preferable lower limit of the content of the filler is 20% by weight, and the more preferable upper limit is 60% by weight.

The sealant for a liquid crystal display element of the present invention preferably contains a silane coupling agent. The silane coupling agent mainly has a role as an adhesive auxiliary for satisfactorily adhering the sealant to the substrate or the like.

The silane coupling agent is excellent in the effect of improving the adhesiveness with a substrate or the like, and can suppress the outflow of the curable resin into the liquid crystal by chemically bonding with the curable resin. Therefore, for example, 3 -Aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-isocyanatepropyltrimethoxysilane and the like are preferably used.

The preferable lower limit of the content of the silane coupling agent in the sealant for a liquid crystal display element of the present invention is 0.1% by weight, and the preferable upper limit is 10% by weight. When the content of the silane coupling agent is within this range, the effect of improving the adhesiveness while suppressing the occurrence of liquid crystal contamination becomes more excellent. The more preferable lower limit of the content of the silane coupling agent is 0.3% by weight, and the more preferable upper limit is 5% by weight.

The sealing agent for a liquid crystal display element of the present invention may contain a light-shielding agent. By containing the above-mentioned light-shielding agent, the sealant for a liquid crystal display element of the present invention can be suitably used as a light-shielding sealant.

Examples of the light-shielding agent include iron oxide, titanium black, aniline black, cyanine black, fullerene, carbon black, and resin-coated carbon black. Of these, titanium black is preferable.

The titanium black is a substance having a higher transmittance in the vicinity of the ultraviolet region, particularly for light having a wavelength of 370 to 450 nm, as compared with the average transmittance for light having a wavelength of 300 to 800 nm. That is, the titanium black has a property of imparting a light-shielding property to the sealant for a liquid crystal display element of the present invention by sufficiently blocking light having a wavelength in the visible light region, while transmitting light having a wavelength in the vicinity of the ultraviolet region. It is a light-shielding agent. As the light-shielding agent contained in the sealant for a liquid crystal display element of the present invention, a substance having a high insulating property is preferable, and as a light-shielding agent having a high insulating property, titanium black is suitable.

The above titanium black exerts a sufficient effect even if it is not surface-treated, but the surface is treated with an organic component such as a coupling agent, silicon oxide, titanium oxide, germanium oxide, aluminum oxide, and oxidation. Surface-treated titanium black, such as those coated with an inorganic component such as zirconium or magnesium oxide, can also be used. Among them, those treated with an organic component are preferable in that the insulating property can be further improved.
Further, the liquid crystal display element manufactured by using the sealant for a liquid crystal display element of the present invention containing the titanium black as a light shielding agent has sufficient light shielding properties, so that there is no light leakage and a high contrast is obtained. It is possible to realize a liquid crystal display element having excellent image display quality.

Among the above titanium blacks, commercially available ones include, for example, 12S, 13M, 13M-C, 13RN, 14M-C (all manufactured by Mitsubishi Materials), Tyrac D (manufactured by Ako Kasei Co., Ltd.) and the like. Can be mentioned.

The preferable lower limit of the specific surface area of the titanium black is 13 m ² / g, the preferable upper limit is 30 m ² / g, the more preferable lower limit is 15 m ² / g, and the more preferable upper limit is 25 m ² / g.
Further, the preferable lower limit of the volume resistance of the titanium black is 0.5 Ω · cm, 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.

The primary particle size of the 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, but the preferable lower limit is 1 nm and the preferable upper limit is 5000 nm. When the primary particle size of the light-shielding agent is in this range, the light-shielding property can be improved without deteriorating the coatability of the obtained sealant for a liquid crystal display element. The more preferable lower limit of the primary particle size of the 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.
The primary particle size of the light-shielding agent can be measured by using NICOMP 380ZLS (manufactured by PARTICLE SIZING SYSTEMS) to disperse the light-shielding agent in a solvent (water, organic solvent, etc.).

The preferable lower limit of the content of the light-shielding agent in the sealant for a liquid crystal display element of the present invention is 5% by weight, and the preferable upper limit is 80% by weight. When the content of the light-shielding agent is within this range, it is possible to exhibit more excellent light-shielding property without deteriorating the adhesion of the obtained sealant for a liquid crystal display element to the substrate, the strength after curing, and the drawing property. can. A more preferable lower limit of the content of the light-shielding agent is 10% by weight, a more preferable upper limit is 70% by weight, a further preferable lower limit is 30% by weight, and a further preferable upper limit is 60% by weight.

The sealant for a liquid crystal display element of the present invention further adds a stress relaxation agent, a reactive diluent, a rocking agent, a spacer, a curing accelerator, a defoaming agent, a leveling agent, a polymerization inhibitor, and others, if necessary. It may contain an agent or the like.

As a method for producing the sealant for a liquid crystal display element of the present invention, for example, a mixer such as a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, or a three-roll mixer is used to polymerize with a curable resin. Examples thereof include a method of mixing an initiator and / or a thermosetting agent with an additive such as a silane coupling agent to be added as needed.

The sealant for a liquid crystal display element of the present invention has a preferable lower limit of 50,000 mPa · s and a preferable upper limit of 700,000 mPa · s measured under the conditions of 25 ° C. and 1 rpm using an E-type viscometer. When the viscosity is in this range, the obtained sealant for a liquid crystal display element has excellent coatability. The more preferable lower limit of the viscosity is 100,000 mPa · s, and the more preferable upper limit is 500,000 mPa · s.
As the E-type viscometer, for example, 5XHBDV-III + CP (Rotor No. CP-51 manufactured by Brookfield) or the like can be used.

By blending conductive fine particles with the sealing agent for a liquid crystal display element of the present invention, a vertically conductive material can be manufactured. A vertically conductive material containing such a sealant for a liquid crystal display element of the present invention and conductive fine particles is also one of the present inventions.

As the conductive fine particles, a metal ball, a resin fine particle having a conductive metal layer formed on the surface thereof, or 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 excellent elasticity of the resin fine particles enables conductive connection without damaging the transparent substrate or the like.

A liquid crystal display element using the sealant for a liquid crystal display element of the present invention or the vertically conductive material of the present invention is also one of the present inventions.

As a method for manufacturing the liquid crystal display element of the present invention, the liquid crystal dropping method is preferably used. Specifically, for example, the sealant for a liquid crystal display element of the present invention is applied to one of two substrates such as a glass substrate with an electrode such as an ITO thin film and a polyethylene terephthalate substrate by screen printing, dispenser coating, or the like. In the process of forming a frame-shaped seal pattern, in a state where the sealant for a liquid crystal display element of the present invention is uncured, fine droplets of liquid crystal are dropped and applied into the frame of the seal pattern of the substrate, and another substrate is laminated under vacuum. The step of matching, the step of irradiating the seal pattern portion of the sealant for the liquid crystal display element of the present invention with light such as ultraviolet rays to temporarily cure the sealant, and the step of heating the temporarily cured sealant to perform main curing. Examples thereof include a method having a process.

According to the present invention, it is possible to provide a sealant for a liquid crystal display element, which has excellent adhesiveness and can suppress liquid crystal contamination. Further, according to the present invention, it is possible to provide a vertically conductive material and a liquid crystal display element using the sealant for a liquid crystal display element.

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

(Preparation of the compound represented by the formula (1) (l = m = n = 0, Y = 2 (average value)))
200 parts by weight of bis (4-hydroxyphenyl) sulfone, 370 parts by weight of epichlorohydrin, 185 parts by weight of dimethyl sulfoxide, and 5 parts by weight of tetramethylammonium chloride were added and dissolved under stirring, and the temperature was raised to 50 ° C. Then, 60 parts by weight of sodium hydroxide was added in portions, and then the reaction was carried out at 50 ° C. for 3 hours. After completion of the reaction, washing with water was carried out, and excess epichlorohydrin and the like were distilled off from the oil layer at 130 ° C. under reduced pressure using an evaporator. 450 parts by weight of methyl isobutyl ketone was added to the residue to dissolve it, and the temperature was raised to 70 ° C. Add 10 parts by weight of a 30% aqueous sodium hydroxide solution under stirring, react for 1 hour, wash with water three times, and distill off methyl isobutyl ketone at 180 ° C. under reduced pressure using a rotary evaporator. did. The obtained substance is reacted with ethyltriphenylphosphonium acetate as a catalyst, then washed with water, and the compound represented by the formula (1) (l = m = n = 0, Y = 2 (average value)). Was synthesized. The fact that the obtained compound is a compound represented by the formula (1) (l = m = n = 0, Y = 2 (average value)) indicates that ¹ H-NMR, ¹³ C-NMR, and Confirmed by IR.

(Preparation of the compound represented by the formula (1) (l = m = n = 1 (average value), Y = 3 (average value))
Add 170 parts by weight of bis [4- (2-hydroxyethoxy) phenyl] sulfone, 370 parts by weight of epichlorohydrin, 185 parts by weight of dimethyl sulfoxide, and 5 parts by weight of tetramethylammonium chloride, dissolve under stirring, and raise to 50 ° C. It was warm. Then, 60 parts by weight of sodium hydroxide was added in portions, and then the reaction was carried out at 50 ° C. for 3 hours. After completion of the reaction, washing with water was carried out, and excess epichlorohydrin and the like were distilled off from the oil layer at 130 ° C. under reduced pressure using an evaporator. 450 parts by weight of methyl isobutyl ketone was added to the residue to dissolve it, and the temperature was raised to 70 ° C. Add 10 parts by weight of a 30% aqueous sodium hydroxide solution under stirring, react for 1 hour, wash with water three times, and distill off methyl isobutyl ketone at 180 ° C. under reduced pressure using a rotary evaporator. did. The obtained substance is reacted with ethyltriphenylphosphonium acetate as a catalyst, then washed with water, and the compound represented by the formula (1) (l = m = n = 1 (average value), Y = 3 ( Average value)) was synthesized. The fact that the obtained compound is a compound represented by the formula (1) (l = m = n = 1 (average value), Y = 3 (average value)) is ¹ H-NMR, ¹³ C-. Confirmed by NMR and IR.

(Examples 1 to 8 and Comparative Examples 1 and 2)
According to the compounding ratios shown in Table 1, each material was mixed using a planetary stirrer (manufactured by Shinky Co., Ltd., "Awatori Rentaro"), and then further mixed using three rolls. The sealants for liquid crystal display elements of No. 8 and Comparative Examples 1 and 2 were prepared.

<Evaluation>
The following evaluations were made on the sealants for liquid crystal display elements obtained in Examples and Comparative Examples. The results are shown in Table 1.

(Applicability)
Using a dispenser (manufactured by Musashi Engineering Co., Ltd., "SHOTMASTER300"), the sealants for each liquid crystal display element obtained in Examples and Comparative Examples were applied onto a glass substrate. When the dispense nozzle is fixed at 400 μm, the nozzle gap is 30 μm, and the application pressure is fixed at 300 kPa, "◎" is applied when the application is successful without blurring or sagging, and "○" is indicated when slight blurring or sagging occurs. The coatability was evaluated as "Δ" when there was no coating breakage but large blurring or sagging, and as "x" when the coating was cut off or could not be applied at all.

(Adhesiveness)
1 part by weight of spacer particles (manufactured by Sekisui Chemical Industry Co., Ltd., "Micropearl SP-2050") having an average particle diameter of 5 μm for 100 parts by weight of the sealant for each liquid crystal display element obtained in Examples and Comparative Examples is a planetary type. Disperse evenly with a stirrer, take a very small amount in the center of Corning glass 1737 (20 mm x 50 mm x 0.7 mm thickness), overlay glass of the same type on it, and spread the sealant for the liquid crystal display element. ^{After irradiating with an ultraviolet ray of 100 mW / cm 2} for 30 seconds using a metal halide lamp, the sealant was cured by heating at 120 ° C. for 1 hour to obtain an adhesion test piece.
The adhesive strength of the obtained adhesive test piece was measured using a tension gauge. The resulting value obtained by dividing measured values (kgf) in the seal coating cross sectional area (cm ²⁾ is a case was 35 kgf / cm ² or more "◎" was 30 kgf / cm ² or more 35 kgf / cm less than ² where "○", the case was 25 kgf / cm ² or more 30 kgf / cm less than ² "△", and evaluated the adhesiveness of the case was less than 25 kgf / cm ² as "×".

(Display performance of liquid crystal display element (low liquid crystal contamination))
1 part by weight of spacer particles (manufactured by Sekisui Chemical Co., Ltd., "Micropearl SP-2050") having an average particle diameter of 5 μm for 100 parts by weight of the sealant for each liquid crystal display element obtained in Examples and Comparative Examples is a planetary type. Disperse evenly with a stirrer, fill the obtained sealant into a dispenser syringe (Musashi Engineering Co., Ltd., "PSY-10E"), perform defoaming treatment, and then dispenser (Musashi Engineering Co., Ltd., "PSY-10E"). In "SHOTMASTER300"), a sealant was applied in a frame shape to one of the transparent electrode substrates with two ITO thin films. Subsequently, minute droplets of TN liquid crystal display (manufactured by Chisso, "JC-5001LA") are dropped and applied into the frame of the sealant by a liquid crystal dropping device, and the other transparent electrode substrate is applied to the other transparent electrode substrate at 5 Pa by a vacuum bonding device. The cells were obtained by laminating under vacuum. ^{The obtained cell was irradiated with ultraviolet rays of 100 mW / cm 2} for 30 seconds using a metal halide lamp, and then heated at 120 ° C. for 1 hour to cure the sealant to obtain a liquid crystal display element.
Regarding the obtained liquid crystal display element, the display unevenness generated in the liquid crystal (particularly the corner part) around the seal portion was visually observed, and when the display unevenness was not confirmed, "◎" was confirmed, and a slight display unevenness was confirmed. The display performance (low liquid crystal contamination) of the liquid crystal display element was evaluated as "○" for the case, "Δ" for the case where the display unevenness was clearly confirmed, and "x" for the case where the severe display unevenness was confirmed.
The liquid crystal display elements having evaluations of "◎" and "○" are at a level where there is no problem in practical use.

According to the present invention, it is possible to provide a sealant for a liquid crystal display element, which has excellent adhesiveness and can suppress liquid crystal contamination. Further, according to the present invention, it is possible to provide a vertically conductive material and a liquid crystal display element using the sealant for a liquid crystal display element.

Claims (6)

It contains a curable resin containing a compound represented by the following formula (1) and a thermosetting agent .
A sealant for a liquid crystal display element, wherein the content of the compound represented by the formula (1) is 1% by weight or more and less than 30% by weight.

In the formula (1), l, m, and n are 0 to 6, respectively, and Y is 1 to 20. The sealant for a liquid crystal display element according to claim 1, wherein Y in the formula (1) is 1 to 10. The sealant for a liquid crystal display element according to claim 1 or 2, wherein l, m, and n in the formula (1) are 1 to 6, respectively. The sealant for a liquid crystal display element according to claim 1, 2 or 3, wherein the thermosetting agent contains a thermosetting agent having trifunctionality or higher. A vertically conductive material comprising the sealant for a liquid crystal display element according to claim 1, 2, 3 or 4, and conductive fine particles. A liquid crystal display element according to claim 1, 2, 3 or 4, wherein the sealant for a liquid crystal display element or the vertically conductive material according to claim 5 is used.