JP5340505B1 - Liquid crystal dropping method sealing agent, vertical conduction material, and liquid crystal display element - Google Patents

Abstract

式（１）中、Ｒ^１、Ｒ^２、及び、Ｒ^３は、水素又はメチル基であり、それぞれ同一であってもよいし、異なっていてもよい。
【選択図】なしDisclosed is a sealing agent for a liquid crystal dropping method which is excellent in coating property, adhesion to an alignment film, and moisture resistance of a cured product, and hardly causes liquid crystal contamination. Moreover, the vertical conduction material and liquid crystal display element which use this sealing compound for liquid crystal dropping methods are provided.
A liquid crystal dropping method sealing agent containing a curable resin and a polymerization initiator, wherein the curable resin is an epoxy resin represented by the following formula (1) and a trifunctional having an isocyanuric skeleton. A (meth) acrylic resin-containing sealing agent for liquid crystal dropping method.
[Chemical 1]

In formula (1), R ¹ , R ² , and R ³ are hydrogen or a methyl group, and may be the same or different.
[Selection figure] None

Description

The present invention relates to a sealant for a liquid crystal dropping method which is excellent in coating property, adhesion to an alignment film, and moisture resistance of a cured product, and hardly causes liquid crystal contamination. Moreover, this invention relates to the vertical conduction material and liquid crystal display element which use this sealing compound for liquid crystal dropping methods.

A liquid crystal display element has a liquid crystal cell in which liquid crystal is sealed in a cell formed by applying a sealing agent to two substrates and bonding them together.
The liquid crystal display cell has two transparent substrates with electrodes facing each other at a predetermined interval, and the periphery thereof is sealed with a sealing agent to form a cell. The liquid crystal is injected into the liquid crystal and the liquid crystal injection port is sealed with a sealant or a sealant.

In recent years, a manufacturing method of a liquid crystal display element called a dripping method using a photocuring thermosetting combined sealant as disclosed in Patent Document 1 has also been studied.
In the dropping method, first, a frame-shaped seal pattern is formed on one of two transparent substrates with electrodes. Next, fine droplets of liquid crystal are applied dropwise onto the entire surface of the seal pattern frame of the transparent substrate in an uncured state of the sealant, the other transparent substrate is stacked under reduced pressure, and the seal portion is irradiated with ultraviolet rays to perform temporary curing. . Thereafter, heating is performed to perform main curing, and a liquid crystal display element is manufactured.

In the conventional liquid crystal display element, the arrangement position of the sealant is mostly on an inorganic material such as glass or ITO, and the sealant is also designed in consideration of the adhesive strength to these inorganic materials. However, along with the recent expansion of applications of liquid crystal display devices, the narrowing of the frame of the liquid crystal display portion has progressed, and a substrate in which a sealant is disposed on the alignment film has been rapidly spreading. There was a problem that the adhesive strength to was insufficient.

JP 2001-133794 A

An object of this invention is to provide the sealing agent for liquid crystal dropping methods which is excellent in coating property, the adhesiveness to alignment film, and the moisture resistance of hardened | cured material, and hardly causes liquid-crystal contamination. Moreover, an object of this invention is to provide the vertical conduction material and liquid crystal display element which use this sealing compound for liquid crystal dropping methods.

The present invention is a sealing agent for a liquid crystal dropping method containing a curable resin and a polymerization initiator, and the curable resin is a trifunctional having an epoxy resin represented by the following formula (1) and an isocyanuric skeleton. It is the sealing compound for liquid crystal dropping methods containing (meth) acrylic resin of this.

In formula (1), R ¹ , R ² , and R ³ are hydrogen or a methyl group, and may be the same or different.

The present invention is described in detail below.
As a curable resin, the present inventors use a combination of an epoxy resin having a specific structure and a trifunctional (meth) acrylic resin having an isocyanuric skeleton, thereby providing a coating property, adhesion to an alignment film, It has been found that a sealant for liquid crystal dropping method can be obtained which is excellent in moisture resistance of the cured product and hardly causes liquid crystal contamination, and has completed the present invention.

The sealing agent for liquid crystal dropping method of the present invention contains a curable resin.
The curable resin contains an epoxy resin represented by the above formula (1). By containing the epoxy resin represented by the above formula (1), the sealing agent for liquid crystal dropping method of the present invention has high moisture resistance of the cured product and low liquid crystal contamination.
Especially, the epoxy resin whose all of R < ¹ >, R < ² > and R < ³ > of the said Formula (1) is a methyl group is preferable.

With respect to the content of the epoxy resin represented by the above formula (1), the preferred lower limit is 5 parts by weight and the preferred upper limit is 45 parts by weight with respect to 100 parts by weight as a whole of the sealing agent for liquid crystal dropping method of the present invention. When the content of the epoxy resin represented by the above formula (1) is less than 5 parts by weight, the obtained sealing agent for liquid crystal dropping method may be inferior in adhesion to a substrate or an alignment film. When the content of the epoxy resin represented by the above formula (1) exceeds 45 parts by weight, the viscosity of the obtained liquid crystal dropping method sealing agent becomes too high, or the affinity with the alignment film is deteriorated and the alignment film It may become inferior to the adhesiveness to. The minimum with more preferable content of the epoxy resin represented by the said Formula (1) is 8 weight part, and a more preferable upper limit is 15 weight part.

The curable resin contains a trifunctional (meth) acrylic resin having an isocyanuric skeleton. Although the epoxy resin represented by the above formula (1) has high adhesion to the substrate and moisture resistance of the cured product, the viscosity is high and the affinity with the alignment film is poor. The sealing agent for liquid crystal dropping method of the present invention contains a trifunctional (meth) acrylic resin having the isocyanuric skeleton in addition to the epoxy resin represented by the above formula (1), thereby providing coating properties and orientation. It has excellent adhesion to the film and moisture resistance of the cured product, and hardly causes liquid crystal contamination.
In the present specification, the “(meth) acrylic” means acryl or methacryl, and the “(meth) acrylic resin” means a resin having a (meth) acryloyl group. The term “(meth) acryloyl group” means an acryloyl group or a methacryloyl group.

The trifunctional (meth) acrylic resin having an isocyanuric skeleton is preferably a compound represented by the following formula (2) and / or a compound represented by the following formula (3). Especially, compared with other trifunctional (meth) acrylic resins having an isocyanuric skeleton, the cured product becomes softer and has an excellent effect of improving the adhesion to the alignment film. The acrylic resin is preferably a compound represented by the following formula (3).

In formula (2), R ⁴ , R ⁵ , and R ⁶ are hydrogen or a methyl group, and may be the same or different.

In formula (3), l, m, and n each independently represent an integer of 0-9, and the sum of l, m, and n is 1-9. R ⁷ , R ⁸ and R ⁹ are hydrogen or a methyl group, and may be the same or different. The total of l, m, and n is preferably 3 to 9 because the cured product becomes soft and is excellent in the effect of improving the adhesion to the alignment film.

Examples of commercially available trifunctional (meth) acrylic resins having an isocyanuric skeleton include M-315 and M-327 (both manufactured by Toagosei Co., Ltd.).

The content of the trifunctional (meth) acrylic resin having an isocyanuric skeleton is preferably 5 parts by weight and preferably 50 parts by weight with respect to 100 parts by weight of the entire sealing agent for liquid crystal dropping method of the present invention. . When the content of the trifunctional (meth) acrylic resin having an isocyanuric skeleton is less than 5 parts by weight, the viscosity of the obtained liquid crystal dropping method sealing agent becomes too high, or the affinity with the alignment film is deteriorated. May be inferior in adhesion to the alignment film. When the content of the trifunctional (meth) acrylic resin having the isocyanuric skeleton exceeds 50 parts by weight, the cured product of the obtained liquid crystal dropping method sealing agent becomes too hard and has poor adhesion to the substrate and the alignment film. It may become. The minimum with more preferable content of the trifunctional (meth) acrylic resin which has the said isocyanuric skeleton is 25 weight part, and a more preferable upper limit is 40 weight part.

The curable resin may contain other epoxy resins in addition to the epoxy resin represented by the formula (1) as long as the object of the present invention is not impaired. It is preferable to contain an epoxy resin.
Examples of the other epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, 2,2′-diallyl bisphenol A type epoxy resin, hydrogenated bisphenol type epoxy resin, and propylene oxide addition. Bisphenol A 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 novolak type epoxy resin, dicyclopentadiene novolak Type epoxy resin, biphenyl novolac type epoxy resin, naphthalene phenol novolac type epoxy resin, glycidylamine type epoxy resin, alkyl And polyol-type epoxy resins, rubber-modified epoxy resins, glycidyl ester compounds, and the like.

As what is marketed among the said bisphenol A type epoxy resins, 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.
As what is marketed among the said bisphenol S-type epoxy resins, Epicron EXA1514 (made by DIC Corporation) etc. are mentioned, for example.
As what is marketed among the said 2,2'- diallyl bisphenol A type epoxy resins, RE-810NM (made by Nippon Kayaku Co., Ltd.) etc. are mentioned, for example.
As what is marketed among the said hydrogenated bisphenol type | mold epoxy resins, Epicron EXA7015 (made by DIC Corporation) etc. are mentioned, for example.
As what is marketed among the said propylene oxide addition bisphenol A type epoxy resins, EP-4000S (made by ADEKA) etc. are mentioned, for example.
As what is marketed among the said biphenyl type epoxy resins, jERYX-4000H (made by Mitsubishi Chemical Corporation) etc. are mentioned, for example.
As what is marketed among the said sulfide type epoxy resins, YSLV-50TE (made by Nippon Steel Chemical Co., Ltd.) etc. are mentioned, for example.
As what is marketed among the said diphenyl ether type epoxy resins, YSLV-80DE (made by Nippon Steel Chemical Co., Ltd.) etc. are mentioned, for example.
As what is marketed among the said dicyclopentadiene type epoxy resins, EP-4088S (made by ADEKA) etc. are mentioned, for example.
As what is marketed among the said naphthalene type | mold epoxy resins, Epicron HP4032, Epicron EXA-4700 (all are the products made from DIC) etc. are mentioned, for example.
As what is marketed among the said phenol novolak-type epoxy resins, Epicron N-770 (made by DIC Corporation) etc. are mentioned, for example.
As what is marketed among the said ortho cresol novolak-type epoxy resins, Epicron N-670-EXP-S (made by DIC) etc. are mentioned, for example.
As what is marketed among the said dicyclopentadiene novolak-type epoxy resins, epiclone HP7200 (made by DIC) etc. are mentioned, for example.
As what is marketed among the said biphenyl novolak-type epoxy resins, NC-3000P (made by Nippon Kayaku Co., Ltd.) etc. are mentioned, for example.
As what is marketed among the said naphthalene phenol novolak-type epoxy resins, ESN-165S (made by Nippon Steel Chemical Co., Ltd.) etc. are mentioned, for example.
As what is marketed among the said glycidyl amine type epoxy resins, jER630 (made by Mitsubishi Chemical Corporation), Epicron 430 (made by DIC Corporation), TETRAD-X (made by Mitsubishi Gas Chemical Co., Inc.) etc. are mentioned, for example.
Examples of commercially available alkyl polyol type epoxy resins include ZX-1542 (manufactured by Nippon Steel Chemical Co., Ltd.), Epicron 726 (manufactured by DIC Corporation), 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 (all manufactured by Nippon Steel Chemical Co., Ltd.), Epolide PB (manufactured by Daicel Chemical Industries, Ltd.), and the like.
As what is marketed among the said glycidyl ester compounds, Denacol EX-147 (made by Nagase ChemteX Corporation) etc. is mentioned, for example.
Other commercially available epoxy resins include, for example, YDC-1312, YSLV-80XY, YSLV-90CR (all manufactured by Nippon Steel Chemical Co., Ltd.), XAC4151 (manufactured by Asahi Kasei Co., Ltd.), jER1031, jER1032 ( These include Mitsubishi Chemical Corporation), EXA-7120 (DIC Corporation), TEPIC (Nissan Chemical Corporation), and the like.

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

The upper limit of the content of the other epoxy resin is preferably 30 parts by weight with respect to 100 parts by weight of the entire sealing agent for liquid crystal dropping method of the present invention. When content of the said other epoxy resin exceeds 30 weight part, the sealing compound for liquid crystal dropping methods obtained may cause liquid crystal contamination. The upper limit with more preferable content of the said other epoxy resin is 15 weight part.

The curable resin may contain other (meth) acrylic resins in addition to the trifunctional (meth) acrylic resin having the isocyanuric skeleton, as long as the object of the present invention is not impaired. It is preferable to contain a bifunctional (meth) acrylic resin as the (meth) acrylic resin.
Examples of the other (meth) acrylic resins include, for example, an ester compound obtained by reacting a compound having a hydroxyl group with (meth) acrylic acid, and an epoxy obtained by reacting (meth) acrylic acid with an epoxy compound. Examples thereof include urethane (meth) acrylates obtained by reacting (meth) acrylates and isocyanates with (meth) acrylic acid derivatives having a hydroxyl group.
In the present specification, the “(meth) acrylate” means acrylate or methacrylate, and the epoxy (meth) acrylate is obtained by reacting all epoxy groups in the epoxy compound with (meth) acrylic acid. Indicates a compound.

Among the ester compounds obtained by reacting the (meth) acrylic acid with a compound having a hydroxyl group, the monofunctional compound is particularly limited as long as it has one (meth) acryloyl group in the molecule. Specifically, for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isobornyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, methoxyethylene glycol (Meth) acrylate, 2-ethoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, benzyl (meth) acrylate, ethyl carbitol (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) Acrylate, phenoxypolyethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, 1H, 1H, 5H-octafluoropentyl (meth) acrylate, imide (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate Propyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isononyl (meth) acrylate, isomyristyl (meth) acrylate, 2-butoxyethyl (meth) Acrylate, 2-phenoxyethyl (meth) acrylate, bicyclopentenyl (meth) acrylate, isodecyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, 2- (meth) acryloyloxyethyl succinic acid 2- (meth) acryloyloxyethyl hexahydrophthalic acid, 2- (meth) acryloyloxyethyl 2-hydroxypropyl phthalate, glycidyl (meth) acrylate, 2- (meth) acryloyllo Examples thereof include xylethyl phosphate.

Examples of the bifunctional ester compound obtained by reacting the above (meth) acrylic acid with a compound having a hydroxyl group include 1,4-butanediol di (meth) acrylate and 1,3-butanediol di (Meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, 2-n-butyl-2-ethyl -1,3-propanediol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) ) Acrylate, Tetra Tylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene oxide-added bisphenol A di (meth) acrylate, ethylene oxide-added bisphenol A di (meth) acrylate, ethylene oxide-added bisphenol F di (meth) acrylate, dimethylol di Cyclopentadienyl di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, neopentyl glycol 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 di (meth) acrylate.

Among the ester compounds obtained by reacting the above (meth) acrylic acid with a compound having a hydroxyl group, those having three or more functional groups include, for example, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, propylene Oxide-added trimethylolpropane tri (meth) acrylate, ethylene oxide-added trimethylolpropane tri (meth) acrylate, caprolactone-modified trimethylolpropane tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate , Ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, glycerin tri (meth) acrylate, pro Ren'okishido added glycerin tri (meth) acrylate, tris (meth) acryloyloxyethyl phosphate, and the like.

The epoxy (meth) acrylate is not particularly limited, and examples thereof 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 other epoxy resin mentioned above etc. are mentioned.

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

The isocyanate used as the raw material of the urethane (meth) acrylate is not particularly limited. For example, isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diphenylmethane-4 , 4'-diisocyanate (MDI), hydrogenated MDI, polymeric MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate, tolidine diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethanetri Isocyanate, tris (isocyanatephenyl) thiophosphate, tetramethylxylene diisocyanate, 1,6,10-undecane triiso Aneto and the like. In addition, for example, chain extension obtained by reaction of polyol such as ethylene glycol, glycerin, sorbitol, trimethylolpropane, (poly) propylene glycol, carbonate diol, polyether diol, polyester diol, polycaprolactone diol and excess isocyanate. Diisocyanate compounds can also be used.

The (meth) acrylic acid derivative having a hydroxyl group, which is a raw material for the urethane (meth) acrylate, is not particularly limited. For example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl Commercial products such as (meth) acrylate and 2-hydroxybutyl (meth) acrylate, and two products such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and polyethylene glycol Mono (meth) acrylates of monohydric alcohols, mono (meth) acrylates or di (meth) acrylates of trivalent alcohols such as trimethylolethane, trimethylolpropane and glycerin, and epoxies such as bisphenol A type epoxy (meth) acrylate ( Data) acrylate, and the like.

Specifically, the urethane (meth) acrylate includes, for example, 134 parts by weight of trimethylolpropane, 0.2 part by weight of BHT as a polymerization inhibitor, 0.01 part by weight of dibutyltin dilaurate as a reaction catalyst, and 666 parts by weight of isophorone diisocyanate. In addition, the mixture can be reacted at 60 ° C. for 2 hours with stirring under reflux. Next, 51 parts by weight of 2-hydroxyethyl acrylate is added, and the mixture is refluxed and stirred at 90 ° C. while feeding air and reacted for 2 hours.

Examples of commercially available urethane (meth) acrylates include M-1100, M-1200, M-1210, M-1600 (all manufactured by Toagosei Co., Ltd.), EBECRYL230, EBECRYL270, EBECRYL4858, EBECRYL8402, EBECRYL8804, EBECRYL8803, EBECRYL8807, EBECRYL9260, EBECRYL1290, EBECRYL5129, EBECRYL4842, EBECRYL210, EBECRYL4827, EBECRYL6700, EBECRYL6700, EBECRYL6700 , Art resin N-1255, Art Resin UN-330, Art Resin UN-3320HB, Art Resin UN-1200TPK, Art Resin SH-500B (all manufactured by Negami Industrial Co., Ltd.), U-2HA, U-2PHA, U-3HA, U- 4HA, U-6H, U-6LPA, U-6HA, U-10H, U-15HA, U-122A, U-122P, U-108, U-108A, U-324A, U-340A, U-340P, U-1084A, U-2061BA, UA-340P, UA-4100, UA-4000, UA-4200, UA-4400, UA-5201P, UA-7100, UA-7200, UA-W2A (all are Shin-Nakamura Chemical Industries Made by company), AI-600, AH-600, AT-600, UA-101I, UA-101T, UA-306H, A-306I, UA-306T (all manufactured by Kyoeisha Chemical Co., Ltd.).

The preferable upper limit of the content of the other (meth) acrylic resin is 70 parts by weight with respect to 100 parts by weight of the entire sealing agent for liquid crystal dropping method of the present invention. If the content of the other (meth) acrylic resin exceeds 70 parts by weight, the resulting liquid crystal dropping method sealing agent may be inferior in adhesion to the substrate or the alignment film. The upper limit with more preferable content of the said other (meth) acrylic resin is 60 weight part.

The ratio of (meth) acryloyl group to epoxy group in the entire curable resin is preferably 50:50 to 95: 5 in terms of molar ratio. When the ratio of the (meth) acryloyl group is less than 50%, a large amount of uncured epoxy resin component is present in the sealing agent for liquid crystal dropping method after curing, which may contaminate the liquid crystal. When the ratio of the (meth) acryloyl group exceeds 95%, the obtained liquid crystal dropping method sealing agent may be inferior in adhesiveness.

The sealing agent for liquid crystal dropping method of the present invention contains a polymerization initiator.
Examples of the polymerization initiator include a radical photopolymerization initiator for reacting (meth) acryloyl groups with light such as ultraviolet rays, a thermal radical polymerization initiator for reacting (meth) acryloyl groups with heat, and an epoxy group with UV. Examples include photocationic polymerization initiators for reaction.

The radical photopolymerization initiator is not particularly limited. Examples of commercially available products include IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACUREOXE01, Lucy TPO (all manufactured by BASF AN Examples thereof include soy methyl ether, benzoin ethyl ether, benzoin isopropyl ether (all manufactured by Tokyo Chemical Industry Co., Ltd.).

Although content of the said radical photopolymerization initiator is not specifically limited, A preferable minimum is 0.1 weight part and a preferable upper limit is 10 weight part with respect to 100 weight part of whole sealing compound for liquid crystal dropping methods of this invention. When the content of the radical photopolymerization initiator is less than 0.1 part by weight, the sealing agent for liquid crystal dropping method of the present invention may not be sufficiently cured. When the content of the radical photopolymerization initiator exceeds 10 parts by weight, the storage stability may be lowered.

The thermal radical polymerization initiator is not particularly limited, and examples thereof include peroxides and azo compounds. Examples of commercially available products include perbutyl O, perhexyl O, perbutyl PV (all manufactured by NOF Corporation), V -30, V-501, V-601, VPE-0201, VPE-0401, VPE-0601 (all manufactured by Wako Pure Chemical Industries, Ltd.) and the like.

Although content of the said thermal radical polymerization initiator is not specifically limited, A preferable minimum is 0.01 weight part and a preferable upper limit is 10 weight part with respect to 100 weight part of whole sealing compound for liquid crystal dropping methods of this invention. When the content of the thermal radical polymerization initiator is less than 0.01 parts by weight, the liquid crystal dropping method sealing agent of the present invention may not be sufficiently cured. When content of the said thermal radical polymerization initiator exceeds 10 weight part, storage stability may fall.

The photocationic polymerization initiator is not particularly limited, and examples of commercially available products include Adekaoptomer SP-150 and Adekaoptomer SP-170 (both manufactured by ADEKA).

Although content of the said photocationic polymerization initiator is not specifically limited, A preferable minimum is 0.1 weight part with respect to 100 weight part of whole sealing agents, and a preferable upper limit is 10 weight part. When the content of the cationic photopolymerization initiator is less than 0.1 part by weight, the sealing agent for liquid crystal dropping method of the present invention may not be sufficiently cured. If the content of the cationic photopolymerization initiator exceeds 10 parts by weight, the storage stability may be lowered.

The sealing agent for liquid crystal dropping method of the present invention preferably contains a thermosetting agent.
Examples of the thermosetting agent include organic acid hydrazides, imidazole derivatives, amine compounds, polyhydric phenol compounds, acid anhydrides, and the like. Of these, organic acid hydrazide is preferably used.

The organic acid hydrazide is not particularly limited, and examples thereof include sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, malonic acid dihydrazide, and the like. ADH (manufactured by Otsuka Chemical Co., Ltd.), Amicure VDH, Amicure VDH-J, Amicure UDH (all manufactured by Ajinomoto Fine Techno Co., Ltd.) and the like can be mentioned.

With respect to the content of the thermosetting agent, a preferable lower limit is 1 part by weight and a preferable upper limit is 50 parts by weight with respect to 100 parts by weight of the entire sealing agent for liquid crystal dropping method of the present invention. When the content of the thermosetting agent is less than 1 part by weight, the sealing agent for liquid crystal dropping method of the present invention may not be sufficiently cured. When the content of the thermal epoxy thermosetting agent exceeds 50 parts by weight, the viscosity of the sealing agent for liquid crystal dropping method of the present invention is increased, which may impair applicability and the like. The upper limit with more preferable content of the said thermosetting agent is 30 weight part.

The sealing agent for liquid crystal dropping method of the present invention preferably contains the photo radical polymerization initiator and the thermosetting agent as a curing reaction system by light and heat.

The sealing agent for liquid crystal dropping method of the present invention may contain a silane coupling agent. The silane coupling agent mainly has a role as an adhesion assistant.
Although the said silane coupling agent is not specifically limited, Since it is excellent in the effect which improves adhesiveness and it can suppress the outflow of curable resin in a liquid crystal by chemically bonding with curable resin, for example, (gamma)- Aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-isocyanatopropyltrimethoxysilane and the like are preferably used. These silane coupling agents may be used alone or in combination of two or more.

The content of the silane coupling agent is such that the preferred lower limit is 0.1 parts by weight and the preferred upper limit is 20 parts by weight with respect to 100 parts by weight of the entire sealing agent for liquid crystal dropping method of the present invention. When the content of the silane coupling agent is less than 0.1 parts by weight, the effect of blending the silane coupling agent may not be sufficiently exhibited. When content of the said silane coupling agent exceeds 20 weight part, the sealing compound for liquid crystal dropping methods obtained may cause 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 dropping method of the present invention preferably contains a filler for the purpose of improving the adhesiveness by the stress dispersion effect, improving the linear expansion coefficient, and the like.
The filler is not particularly limited. For example, 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 Organic fillers such as aluminum hydroxide, 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, etc. A filler is mentioned. These fillers may be used independently and may use 2 or more types together.

The content of the filler is such that a preferable lower limit is 5 parts by weight and a preferable upper limit is 70 parts by weight with respect to 100 parts by weight of the entire sealing agent for liquid crystal dropping method of the present invention. When the content of the filler is less than 5 parts by weight, effects such as improvement of adhesiveness may not be sufficiently exhibited. When content of the said filler exceeds 70 weight part, the viscosity of the sealing compound for liquid crystal dropping methods obtained will become high, and applicability | paintability may worsen. The minimum with more preferable content of the said filler is 10 weight part, and a more preferable upper limit is 60 weight part.

The sealing agent for liquid crystal dropping method of the present invention may contain a light shielding agent. By containing the said light shielding agent, the sealing compound for liquid crystal dropping methods of this invention can be used suitably as a light shielding sealing agent.

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 with a wavelength of 370 to 450 nm, compared to the average transmittance for light with a wavelength of 300 to 800 nm. That is, the above-described titanium black sufficiently shields light having a wavelength in the visible light region, thereby providing light shielding properties to the sealing agent for liquid crystal dropping method of the present invention, while transmitting light having a wavelength in the vicinity of the ultraviolet region. A shading agent. Therefore, the liquid crystal of the present invention can be used by using the photo radical polymerization initiator or the photo cationic polymerization initiator that can start the reaction with light having a wavelength (370 to 450 nm) at which the transmittance of the titanium black is high. The photocurability of the sealing agent for the dripping method can be further increased. On the other hand, the light shielding agent contained in the liquid crystal dropping method sealing agent of the present invention is preferably a highly insulating material, and titanium black is also suitable as the highly insulating light shielding agent.
The titanium black preferably has an optical density (OD value) per μm of 3 or more, more preferably 4 or more. The higher the light-shielding property of the titanium black, the better. The OD value of the titanium black is not particularly limited, but is usually 5 or less.

The above-mentioned titanium black exhibits 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, oxidized Surface-treated titanium black such as those coated with an inorganic component such as zirconium or magnesium oxide can also be used. Especially, what is processed with the organic component is preferable at the point which can improve insulation more.
In addition, the liquid crystal display device manufactured using the sealing agent for liquid crystal dropping method of the present invention containing the above-described titanium black as a light-shielding agent has a sufficient light-shielding property, and thus has a high contrast without light leakage. A liquid crystal display element having excellent image display quality can be realized.

Examples of commercially available titanium black include 12S, 13M, 13M-C, 13R-N (all manufactured by Mitsubishi Materials Corporation), Tilak D (manufactured by Ako Kasei Co., Ltd.), and the like.

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 preferred lower limit of the volume resistance of the titanium black is 0.5 Ω · cm, the preferred upper limit is 3 Ω · cm, the more preferred lower limit is 1 Ω · cm, and the more preferred upper limit is 2.5 Ω · cm.

The primary particle diameter of the light-shielding agent is not particularly limited as long as it is not more than the distance between the substrates of the liquid crystal display element, but the preferred lower limit is 1 nm and the preferred upper limit is 5 μm. When the primary particle size of the light-shielding agent is less than 1 nm, the viscosity and thixotropy of the obtained liquid crystal dropping method sealing agent are greatly increased, and workability may be deteriorated. When the primary particle diameter of the light-shielding agent exceeds 5 μm, the coating property of the obtained liquid crystal dropping method sealing agent on the substrate may be deteriorated. The more preferable lower limit of the primary particle diameter of the light shielding agent is 5 nm, the more preferable upper limit is 200 nm, the still more preferable lower limit is 10 nm, and the still more preferable upper limit is 100 nm.

The content of the light-shielding agent is preferably 5 parts by weight with a preferred lower limit and 80 parts by weight with respect to 100 parts by weight of the entire sealing agent for liquid crystal dropping method of the present invention. If the content of the light shielding agent is less than 5 parts by weight, sufficient light shielding properties may not be obtained. When the content of the light-shielding agent exceeds 80 parts by weight, the adhesion of the obtained sealing agent for liquid crystal dropping method to the substrate and the strength after curing may be lowered, or the drawing property may be lowered. The more preferable lower limit of the content of the light shielding agent is 10 parts by weight, the more preferable upper limit is 70 parts by weight, the still more preferable lower limit is 30 parts by weight, and the still more preferable upper limit is 60 parts by weight.

The sealing agent for the liquid crystal dropping method of the present invention further includes a reactive diluent for adjusting the viscosity, a thixotropic agent for adjusting the thixotropy, a spacer such as a polymer bead for adjusting the panel gap, if necessary. It may contain a curing accelerator such as -P-chlorophenyl-1,1-dimethylurea, an antifoaming agent, a leveling agent, a polymerization inhibitor, and other additives.

The method for producing the sealing agent for liquid crystal dropping method of the present invention is not particularly limited. For example, a curable resin, a polymerization initiator, and an additive blended as necessary are used in three rolls. The method of mixing by a conventionally well-known method and making it disperse | distribute uniformly is mentioned. At this time, in order to remove ionic impurities, it may be brought into contact with an ion-adsorbing solid such as a layered silicate mineral.

A vertical conduction material can be produced by blending conductive fine particles with the sealant for the liquid crystal dropping method of the present invention. If such a vertical conduction material is used, the electrodes can be reliably conductively connected.
The vertical conduction material containing the sealing agent for liquid crystal dropping method 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, for example, 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 dropping method of the present invention or the vertical conduction material of the present invention is also one aspect of the present invention.
As a method for producing the liquid crystal display element of the present invention, for example, on one of the substrates having an electrode such as an ITO thin film and an alignment film, the sealing agent for the liquid crystal dropping method of the present invention is formed into a rectangular shape by screen printing, dispenser application or the like. Forming a seal pattern of the liquid crystal, applying a droplet of liquid crystal to the entire surface of the frame of the seal pattern, applying the other substrate under vacuum, and applying the ultraviolet light to the sealant for the liquid crystal dropping method of the present invention. Examples of the method include a step of irradiating light to temporarily cure the sealing agent and a step of heating and temporarily curing the temporarily cured sealing agent.

ADVANTAGE OF THE INVENTION According to this invention, the sealing compound for liquid crystal dropping methods which is excellent in coating property, the adhesiveness to alignment film, and the moisture resistance of hardened | cured material, and hardly causes liquid crystal contamination 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 dropping methods 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.

(Examples 1-19, Comparative Examples 1-4)
According to the blending ratio described in Tables 1 to 3, each material was mixed using a planetary stirrer (“Shinky Co., Ltd.“ Awatori Netaro ”), and then further mixed using three rolls. The sealing agent for liquid crystal dropping methods of Examples 1-19 and Comparative Examples 1-4 was prepared.
In addition, “VG3101” used as the epoxy resin represented by the formula (1) is a compound represented by the above formula (1), in which R ¹ , R ² , and R ³ are methyl groups.
Further, “Aronix M-315” used as a trifunctional (meth) acrylic resin having an isocyanuric skeleton is represented by the above formula (2), and R ⁴ , R ⁵ , and R ⁶ are hydrogen compounds. “Aronix M-327” is a compound represented by the above formula (3), wherein the total of l, m, and n is 3, and R ⁷ , R ⁸ , and R ⁹ are hydrogen.

<Evaluation>
The following evaluation was performed about the sealing agent for liquid crystal dropping methods obtained by the Example and the comparative example. The results are shown in Tables 1-3.

(1) Using a coating dispenser (manufactured by Musashi Engineering Co., Ltd., “SHOTMASTER300”), the sealing agent obtained in each Example and each Comparative Example was used as a glass substrate with a TN alignment film SE7492 (Nissan Chemical Co., Ltd.). The coating property when applied to was evaluated. When dispensing with a dispensing nozzle of 400 μm, a nozzle gap of 30 μm, and a coating pressure of 300 kPa, “◎” indicates that the coating can be applied without fading, and “○” indicates that the coating can be applied with little fading. The coating property was evaluated as “Δ” when it occurred and “x” when it could not be applied at all.

(2) Adhesive strength with respect to substrate with alignment film Polymer beads having an average particle diameter of 5 μm (“Micropearl” manufactured by Sekisui Chemical Co., Ltd.) with respect to 100 parts by weight of the sealing agent for liquid crystal dropping method obtained in each of Examples and Comparative Examples SP ") 1 part by weight was dispersed with a planetary stirrer to obtain a uniform liquid. A very small amount of the obtained liquid is taken in the center of a glass substrate (20 mm × 50 mm × 0.7 mmt) with a TN alignment film SE7942 (manufactured by Nissan Chemical Industries, Ltd.), and the same type of glass substrate is overlaid thereon. The sealing agent for the liquid crystal dropping method was spread so as to be about 2.7 to 3.3 mmφ. In that state, 100 mW / cm ² of ultraviolet rays were irradiated for 30 seconds. Then, it heated at 120 degreeC for 1 hour, and obtained the adhesion test piece. About the obtained adhesion test piece, the adhesive strength was measured using the tension gauge.

(3) Display performance of liquid crystal display element (evaluation of color unevenness of liquid crystal display element immediately after fabrication, after storage at high temperature, and after storage at high temperature and high humidity)
1 part by weight of polymer beads having an average particle size of 5 μm (“Smisui Chemical Co., Ltd.,“ Micropearl SP ”) with respect to 100 parts by weight of the sealing agent for liquid crystal dropping method obtained in each Example and each Comparative Example was planetary stirred. Dispersed by an apparatus to obtain a uniform liquid, the resulting liquid was filled into a dispensing syringe (“PSY-10E” manufactured by Musashi Engineering Co., Ltd.) and subjected to defoaming treatment. Next, a sealant was applied to an ITO glass substrate with a TN alignment film SE 7492 (Nissan Chemical Industry Co., Ltd.) with a dispenser (manufactured by Musashi Engineering, “SHOTMASTER 300”) so as to draw a rectangular frame. Subsequently, fine droplets of TN liquid crystal (manufactured by Chisso Corporation, “JC-5001LA”) were dropped and applied with a liquid crystal dropping device, and the other substrate was bonded with a vacuum bonding device under a reduced pressure of 1 Pa. The substrate after bonding was put into a UV irradiator and irradiated with 100 mW / cm ² ultraviolet rays for 30 seconds to temporarily cure the sealant, and then thermally cured in a 120 ° C. oven for 1 hour, A liquid crystal display element was produced. A voltage was applied to the obtained liquid crystal display element and observed visually. "◎" when no color unevenness is seen around the sealant part, "○" when there is almost no color unevenness but a slight color unevenness is seen when looking closely, The display performance was evaluated as “C” where “Δ” was a clear dark color irregularity.
Further, after the obtained liquid crystal display element was stored for 500 hours in an environment of 80 ° C., the display performance was evaluated in the same manner.
Furthermore, after the liquid crystal display element produced in the same manner was stored in an environment of 60 ° C. and 50% RH for 500 hours, the display performance was similarly evaluated.

ADVANTAGE OF THE INVENTION According to this invention, the sealing compound for liquid crystal dropping methods which is excellent in coating property, the adhesiveness to alignment film, and the moisture resistance of hardened | cured material, and hardly causes liquid crystal contamination 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 dropping methods can be provided.

Claims (6)

A liquid crystal dropping method sealing agent containing a curable resin and a polymerization initiator,
The said curable resin contains the epoxy resin represented by following formula (1), and the trifunctional (meth) acrylic resin which has an isocyanuric skeleton, The sealing compound for liquid crystal dropping methods characterized by the above-mentioned.

In formula (1), R ¹ , R ² , and R ³ are hydrogen or a methyl group, and may be the same or different. The liquid crystal according to claim 1, wherein the trifunctional (meth) acrylic resin having an isocyanuric skeleton is a compound represented by the following formula (2) and / or a compound represented by the following formula (3). Sealing agent for dripping method.

In formula (2), R ⁴ , R ⁵ , and R ⁶ are hydrogen or a methyl group, and may be the same or different.

In formula (3), l, m, and n each independently represent an integer of 0-9, and the sum of l, m, and n is 1-9. R ⁷ , R ⁸ and R ⁹ are hydrogen or a methyl group, and may be the same or different. The sealing agent for liquid crystal dropping method according to claim 2, wherein the trifunctional (meth) acrylic resin having an isocyanuric skeleton is a compound represented by the formula (3). 4. The sealing agent for liquid crystal dropping method according to claim 1, 2 or 3, further comprising a light shielding agent. A vertical conduction material comprising the sealing agent for liquid crystal dropping method according to claim 1, 2, 3, or 4, and conductive fine particles. A liquid crystal display element comprising the sealing agent for liquid crystal dropping method according to claim 1, or the vertical conduction material according to claim 5.