JP6659417B2 - Liquid crystal sealant and liquid crystal display cell using the same - Google Patents

Description

  The present invention relates to a liquid crystal sealant that is cured by light and / or heat and is used in a liquid crystal dropping method. More specifically, the present invention relates to a liquid crystal sealant for a liquid crystal dropping method, which has a high adhesive strength to an alignment film, particularly a photo alignment film, and also has excellent general properties such as low liquid crystal contamination and moisture resistance.

  With the recent increase in size of liquid crystal display cells, a so-called liquid crystal dropping method with higher productivity has been proposed as a method for manufacturing liquid crystal display cells (see Patent Documents 1 and 2). Specifically, this is a method for manufacturing a liquid crystal display cell in which liquid crystal is dropped by dropping liquid crystal inside a liquid crystal sealant weir formed on one substrate and then bonding the other substrate.

  However, in the liquid crystal dropping method, the liquid crystal sealant in an uncured state comes into contact with the liquid crystal. At this time, the components of the liquid crystal sealant dissolve (elute) in the liquid crystal, lowering the resistance value of the liquid crystal, and causing There is a problem that display defects occur.

In order to solve this problem, a liquid crystal sealing agent for a liquid crystal dropping method has been used and is now in practical use (Patent Documents 3 and 4). The liquid crystal dropping method using the liquid crystal sealant is characterized in that the liquid crystal sealant sandwiched between the substrates is irradiated with light to perform primary curing, and then is heated and secondary cured. According to this method, the uncured liquid crystal sealant can be quickly cured by light, and the dissolution (elution) of the liquid crystal sealant component into the liquid crystal can be suppressed. Furthermore, the problem of insufficient adhesive strength due to curing shrinkage and the like at the time of photocuring only occurs with photocuring alone, but with the combined use of light and heat, the secondary curing by heating can provide a stress relaxation effect, and such a problem can be solved. Having.
With the practical use of this photothermosetting liquid crystal sealing agent for liquid crystal dropping method, the liquid crystal dropping method has become a generally used method.

However, recently, various improvements have been made for the purpose of higher definition, higher brightness, narrower frame, etc. of the liquid crystal display, and the characteristics required for the liquid crystal sealant for the liquid crystal dropping method have been changed accordingly. ing.
One of them is to improve the adhesive strength to the alignment film. This is because the liquid crystal sealant for the liquid crystal dropping method is disposed on the alignment film portion, and the line width (the width of the liquid crystal sealant) is also reduced, and the area to be adhered is reduced.
In addition, improvement of adhesion to a photo-alignment film, which has recently been used, is becoming an important issue, and a liquid crystal sealant for a liquid crystal dropping method has not yet been proposed that is sufficiently satisfactory.

One of the characteristics required for the liquid crystal sealant for the liquid crystal dropping method is moisture resistance reliability. This is because, for example, there is a problem that a defect occurs in driving of the liquid crystal exposed to the moist heat environment. Although this problem has occurred in a liquid crystal display cell manufactured by a conventional liquid crystal injection method, it is particularly remarkable in a liquid crystal display cell manufactured by a liquid crystal dropping method. In order to solve this problem, various devices have been conventionally devised. For example, the reaction rate is improved by adding a thermal radical polymerization initiator or a curing accelerator, or a material having low solubility in liquid crystal is used as a component.
However, these studies have not led to the realization of a liquid crystal sealant for a liquid crystal dropping method that sufficiently solved the above-mentioned problems.

JP-A-63-179323 JP-A-10-239694 Japanese Patent No. 3583326 JP 2004-61925 A

  The present invention relates to a liquid crystal sealant for a liquid crystal dropping method, which is cured by light and / or heat, and has a high adhesive strength to an alignment film, particularly to a photo alignment film, and has a low liquid crystal contamination property and moisture resistance. Because it is excellent in general characteristics, it proposes a liquid crystal sealant for liquid crystal dropping method that realizes high definition, high brightness, narrow frame, high speed response, low voltage drive, and long life of liquid crystal display element It is.

The present inventors have conducted intensive studies in order to solve the above-mentioned problems. As a result, (A) the epoxy compound represented by the following formula (1) has improved adhesion to a photo-alignment film and has low liquid crystal contamination. The present invention has been found to be realized, and has led to the present invention.
That is, the present invention relates to the following 1) to 17). In addition, in this specification, when it describes as "(meth) acryl", it shall mean "acryl" and / or "methacryl." Further, the “liquid crystal sealant for liquid crystal dropping method” may be simply described as “liquid crystal sealant”.
In the present specification, the superscript RTM means a registered trademark.

（式中ｎは平均重合度を表し、１〜１０の正数である。複数存在するＲは、それぞれ独立に水素原子、又は下記式（２）で表される基を表す。

式（２）中波線は、結合位置を表す。）
２）
上記成分（Ａ）が下記式（３）で表されるエポキシ化合物である請求項１に記載の液晶滴下工法用液晶シール剤。

（式中ｍは平均重合度を表し、１〜１０の正数である。複数存在するＳは、それぞれ独立に水素原子、又は下記式（４）で表される基を表す。

式（４）中波線は、結合位置を表す。）
３）
上記成分（Ｂ）が分子内に酸素−酸素結合（−Ｏ−Ｏ−）及び窒素−窒素結合（−Ｎ＝Ｎ−）を含まない熱ラジカル重合開始剤である上記１）又は２）に記載の液晶滴下工法用液晶シール剤。
４）
更に、（Ｃ）成分（Ａ）以外のエポキシ化合物を含有する上記１）乃至３）のいずれか一項に記載の液晶滴下工法用液晶シール剤。
５）
更に、（Ｄ）（メタ）アクリル化合物を含有する上記１）乃至４）のいずれか一項に記載の液晶滴下工法用液晶シール剤。
６）
更に、（Ｅ）イミダゾール化合物を含有する上記１）乃至５）のいずれか一項に記載の液晶滴下工法用液晶シール剤。
７）
上記成分（Ｅ）が２，４−ジアミノ−６−[２’−メチルイミダゾリル−(１’)]−エチル−s−トリアジンイソシアヌル酸付加物である上記６）に記載の液晶滴下工法用液晶シール剤。
８）
更に、（Ｆ）有機フィラーを含有する上記1）乃至７）のいずれか一項に記載の液晶滴下工法用液晶シール剤。
９）
上記成分（Ｆ）が、ウレタン微粒子、アクリル微粒子、スチレン微粒子、スチレンオレフィン微粒子、及びシリコーン微粒子からなる群より選択される１又は２以上の有機フィラーである上記１）乃至８）のいずれか一項に記載の液晶滴下工法用液晶シール剤。
１０）
更に、（Ｇ）光ラジカル重合開始剤を含有する上記１）乃至９）のいずれか一項に記載の液晶滴下工法用液晶シール剤。
１１）
更に、（Ｈ）無機フィラーを含有する上記１）乃至１０）のいずれか一項に記載の液晶滴下工法用液晶シール剤。
１２）
更に、（Ｉ）熱硬化剤を含有する上記１）乃至１１）のいずれか一項に記載の液晶滴下工法用液晶シール剤。
１３）
上記成分（Ｉ）が有機酸ヒドラジドである上記１２）に記載の液晶滴下工法用液晶シール剤。
１４）
更に（Ｊ）シランカップリング剤を含有する上記１）乃至１３）のいずれか一項に記載の液晶滴下工法用液晶シール剤。
１５）
更に（Ｋ）チオール化合物を含む上記１）乃至１４）のいずれか一項に記載の液晶滴下工法用液晶シール剤。
１６）
２枚の基板により構成される液晶表示セルにおいて、一方の基板に形成された上記１）乃至１５）のいずれか一項に記載の液晶滴下工法用液晶シール剤の堰の内側に液晶を滴下した後、もう一方の基板を貼り合わせ、その後光及び／又は熱により硬化することを特徴とする液晶表示セルの製造方法。
１７）
上記１）乃至１５）のいずれか一項に記載の液晶滴下工法用液晶シール剤を硬化して得られる硬化物でシールされた液晶表示セル。 1)
A liquid crystal sealing agent for a liquid crystal dropping method, comprising (A) an epoxy compound represented by the following formula (1) and (B) a thermal radical polymerization initiator.

(In the formula, n represents an average degree of polymerization and is a positive number of 1 to 10. A plurality of Rs each independently represent a hydrogen atom or a group represented by the following formula (2).

The wavy line in the equation (2) indicates the bonding position. )
2)
The liquid crystal sealant according to claim 1, wherein the component (A) is an epoxy compound represented by the following formula (3).

(In the formula, m represents an average degree of polymerization and is a positive number of 1 to 10. A plurality of Ss independently represent a hydrogen atom or a group represented by the following formula (4).

The middle dashed line in the equation (4) indicates the bonding position. )
3)
The above-mentioned component (1) or (2), wherein the component (B) is a thermal radical polymerization initiator containing no oxygen-oxygen bond (-O-O-) and nitrogen-nitrogen bond (-N = N-) in the molecule. Liquid crystal sealant for liquid crystal dripping method.
4)
Furthermore, (C) The liquid crystal sealing agent for a liquid crystal dropping method according to any one of the above (1) to (3), further comprising an epoxy compound other than the component (A).
5)
Furthermore, (D) The liquid crystal sealing agent for a liquid crystal dropping method according to any one of the above 1) to 4), further comprising a (meth) acrylic compound.
6)
Furthermore, (E) The liquid crystal sealant for a liquid crystal dropping method according to any one of the above 1) to 5), further comprising an imidazole compound.
7)
The liquid crystal seal for a liquid crystal dropping method according to the above item 6), wherein the component (E) is an adduct of 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine isocyanuric acid. Agent.
8)
Furthermore, (F) The liquid crystal sealing agent for a liquid crystal dropping method according to any one of the above 1) to 7), further comprising an organic filler.
9)
The above-mentioned component (F), wherein the component (F) is one or more organic fillers selected from the group consisting of urethane fine particles, acrylic fine particles, styrene fine particles, styrene olefin fine particles, and silicone fine particles. Liquid crystal sealing agent for liquid crystal dropping method according to 4.
10)
Furthermore, (G) The liquid crystal sealing agent for a liquid crystal dropping method according to any one of the above 1) to 9), further comprising a photoradical polymerization initiator.
11)
Furthermore, (H) The liquid crystal sealing agent for a liquid crystal dropping method according to any one of the above 1) to 10), further comprising an inorganic filler.
12)
Furthermore, the liquid crystal sealing agent for a liquid crystal dropping method according to any one of the above 1) to 11), further comprising (I) a thermosetting agent.
13)
The liquid crystal sealing agent for a liquid crystal dropping method according to the above item 12), wherein the component (I) is an organic acid hydrazide.
14)
The liquid crystal sealing agent for a liquid crystal dropping method according to any one of the above 1) to 13), further comprising (J) a silane coupling agent.
15)
The liquid crystal sealing agent for a liquid crystal dropping method according to any one of the above 1) to 14), further comprising (K) a thiol compound.
16)
In a liquid crystal display cell composed of two substrates, liquid crystal is dropped inside the weir of the liquid crystal sealant for liquid crystal dropping method according to any one of the above 1) to 15) formed on one substrate. A method of manufacturing a liquid crystal display cell, comprising: bonding another substrate, and then curing the substrate by light and / or heat.
17)
A liquid crystal display cell sealed with a cured product obtained by curing the liquid crystal sealant for a liquid crystal dropping method according to any one of 1) to 15).

  The liquid crystal sealant for a liquid crystal dropping method of the present invention has a high adhesive strength to an alignment film, particularly a photo alignment film, and also has excellent general properties such as low liquid crystal contamination and moisture resistance. Very useful as a sealant.

[(A) Epoxy compound represented by formula (1)]
The liquid crystal sealant of the present invention contains (A) the epoxy compound represented by the above formula (1).
Since the component (A) has two or more epoxy groups in the molecule, it has high reactivity and can realize low liquid crystal contamination. Further, since it has flexibility, the adhesive strength to the photo-alignment film is low. high.
In the above formula (1), n represents an average degree of polymerization and is a positive number of 1 to 10.
Further, a plurality of Rs independently represent a hydrogen atom or a group represented by the above formula (2).

  The epoxy compound represented by the above formula (1) is more preferably the epoxy compound represented by the above formula (3).

  The content of the component (A) is preferably 1 to 30% by mass, more preferably 5 to 20% by mass, and particularly preferably 8 to 15% by mass based on the total amount of the liquid crystal sealing agent.

[(B) Thermal radical polymerization initiator]
The liquid crystal sealant of the present invention contains (B) a thermal radical polymerization initiator (hereinafter, also simply referred to as component (B)).
The thermal radical polymerization initiator is not particularly limited as long as it is a compound that generates a radical by heating and initiates a chain polymerization reaction, and examples thereof include an organic peroxide, an azo compound, a benzoin compound, a benzoin ether compound, an acetophenone compound, and benzopinacol. And benzopinacol is preferably used. For example, as organic peroxides, Kayamec ^RTM A, M, R, L, LH, SP-30C, Parkadox CH-50L, BC-FF, Kadox B-40ES, Parkadox 14, Trigonox ^RTM 22-70E, 23-C70, 121, 121-50E, 121-LS50E, 21-LS50E, 42, 42LS, Kayaester ^RTM P-70, TMPO-70, CND-C70, OO-50E, AN, Kayabutyl ^RTM B, Parkadox 16 , Kayacarbon ^RTM BIC-75, AIC-75 (manufactured by Kayaku Akzo), Permec ^RTM N, H, S, F, D, G, Perhexa ^RTM H, HC, PATMH, C, V, 22, MC, Percure ^RTM AH, AL, HB, Perbutyl ^RTM H, C, ND, L, Park Mill ^{RT M} H, D, Peroyl ^RTM IB, IPP, Perocta ^RTM ND, is available as such is a commercially available product (manufactured by NOF Co., Ltd.).

  As the azo compound, VA-044, V-070, VPE-0201, VSP-1001 (manufactured by Wako Pure Chemical Industries, Ltd.) and the like are commercially available. In addition, in this specification, superscript RTM means a registered trademark.

Preferred as the component (B) is a thermal radical polymerization initiator having no oxygen-oxygen bond (-OO-) or nitrogen-nitrogen bond (-N = N-) in the molecule. A thermal radical polymerization initiator having an oxygen-oxygen bond (-O-O-) or a nitrogen-nitrogen bond (-N = N-) in a molecule emits a large amount of oxygen or nitrogen when a radical is generated. There is a possibility that the resin may be cured while leaving air bubbles therein, thereby lowering properties such as adhesive strength. Benzopinacol-based thermal radical polymerization initiators (including those obtained by chemically modifying benzopinacol) are particularly preferred. Specifically, benzopinacol, 1,2-dimethoxy-1,1,2,2-tetraphenylethane, 1,2-diethoxy-1,1,2,2-tetraphenylethane, 1,2-diphenoxy- 1,1,2,2-tetraphenylethane, 1,2-dimethoxy-1,1,2,2-tetra (4-methylphenyl) ethane, 1,2-diphenoxy-1,1,2,2-tetra (4-methoxyphenyl) ethane, 1,2-bis (trimethylsiloxy) -1,1,2,2-tetraphenylethane, 1,2-bis (triethylsiloxy) -1,1,2,2-tetraphenyl Ethane, 1,2-bis (t-butyldimethylsiloxy) -1,1,2,2-tetraphenylethane, 1-hydroxy-2-trimethylsiloxy-1,1,2,2-tetraphenylethane, 1- Hydroxy-2-trier Lucyloxy-1,1,2,2-tetraphenylethane, 1-hydroxy-2-t-butyldimethylsiloxy-1,1,2,2-tetraphenylethane and the like, and preferably 1-hydroxy-2. -Trimethylsiloxy-1,1,2,2-tetraphenylethane, 1-hydroxy-2-triethylsiloxy-1,1,2,2-tetraphenylethane, 1-hydroxy-2-t-butyldimethylsiloxy-1 , 1,2,2-tetraphenylethane and 1,2-bis (trimethylsiloxy) -1,1,2,2-tetraphenylethane, more preferably 1-hydroxy-2-trimethylsiloxy-1,1 1,2,2-tetraphenylethane and 1,2-bis (trimethylsiloxy) -1,1,2,2-tetraphenylethane, and particularly preferably 1,2-biphenylethane. It is (trimethylsiloxy) 1,1,2,2-phenylethane.
The benzopinacol is commercially available from Tokyo Chemical Industry Co., Ltd., Wako Pure Chemical Industries, Ltd. or the like. Etherification of the hydroxy group of benzopinacol can be easily performed by a well-known method. Silyl etherification of the hydroxy group of benzopinacol can be obtained by synthesizing the corresponding benzopinacol and various silylating agents by heating under a basic catalyst such as pyridine. Examples of the silylating agent include trimethylsilylating agents (TMCS), hexamethyldisilazane (HMDS), N, O-bis (trimethylsilyl) trifluoroacetamide (BSTFA) and triethylsilylating agents which are generally known trimethylsilylating agents. Examples of triethylchlorosilane (TECS) and t-butylmethylsilane (TBMS) as a t-butyldimethylsilylating agent. These reagents can be easily obtained from markets such as silicon derivative manufacturers. The reaction amount of the silylating agent is preferably 1.0 to 5.0 moles per 1 mole of the hydroxy group of the target compound. More preferably, it is 1.5 to 3.0 times mol. If the amount is less than 1.0 mole, the reaction efficiency is poor and the reaction time is prolonged, so that thermal decomposition is promoted. If the molar ratio is more than 5.0 times, the separation becomes poor at the time of recovery, and the purification becomes difficult.

  The component (B) preferably has a small particle size and is uniformly dispersed. The average particle size is preferably 5 μm or less, more preferably 3 μm or less, because if the average particle size is too large, it causes a failure factor such as a failure in forming a gap when bonding the upper and lower glass substrates in manufacturing a narrow gap liquid crystal display cell. . In addition, the fineness can be infinitely small, but the lower limit is usually about 0.1 μm. The particle size can be measured by a laser diffraction / scattering type particle size distribution analyzer (dry type) (manufactured by Seishin Enterprise Co., Ltd .; LMS-30).

  The content of the component (B) is preferably 0.0001 to 10% by mass, more preferably 0.0005 to 5% by mass, and more preferably 0.001 to 3% by mass based on the total amount of the liquid crystal sealant. Is particularly preferred.

[(C) Epoxy compound other than component (A)]
The liquid crystal sealing agent of the present invention contains an epoxy compound other than the component (A) (C) (hereinafter, also simply referred to as the component (C)) to further improve the adhesive strength.
The epoxy compound is not particularly limited, but is preferably a bifunctional or higher functional epoxy compound, for example, bisphenol A type epoxy compound, bisphenol F type epoxy compound, bisphenol S type epoxy compound, bisphenol A novolak type epoxy compound, bisphenol F novolak type epoxy compound, alicyclic epoxy compound, aliphatic chain epoxy compound, glycidyl ester type epoxy compound, glycidylamine type epoxy compound, hydantoin type epoxy compound, isocyanurate type epoxy compound, phenol novolak having triphenolmethane skeleton Epoxy compounds, epoxy compounds having a biphenyl skeleton, diglycidyl etherified compounds of bifunctional phenols, and diglycidyl ethers of bifunctional alcohols Ether compound, and their halides, and the like hydrogenated product. Of these, bisphenol-type epoxy compounds are preferred from the viewpoint of liquid crystal contamination. These epoxy compounds can be used as a mixture of two or more kinds.

  The content of the component (C) in the liquid crystal sealant of the present invention is usually 0.1 to 30% by mass, preferably 1 to 20% by mass, and more preferably 2 to 10% by mass.

[(D) (meth) acrylic compound]
Examples of the (meth) acrylic compound include (meth) acrylic ester and epoxy (meth) acrylate. Examples of the (meth) acrylic ester include benzyl methacrylate, cyclohexyl methacrylate, glycerol dimethacrylate, glycerol triacrylate, EO-modified glycerol triacrylate, pentaerythritol acrylate, trimethylolpropane triacrylate, tris (acryloxyethyl) isocyanurate, dipentaerythritol Hexaacrylate, phlorogrisinol triacrylate and the like can be mentioned. Epoxy (meth) acrylate can be obtained by a known method by reacting an epoxy compound with (meth) acrylic acid. The epoxy compound serving as a raw material is not particularly limited, but is preferably a bifunctional or higher epoxy compound. For example, a bisphenol A epoxy compound, a bisphenol F epoxy compound, a bisphenol S epoxy compound, a phenol novolak epoxy compound , Cresol novolak epoxy compound, bisphenol A novolak epoxy compound, bisphenol F novolak epoxy compound, alicyclic epoxy compound, aliphatic chain epoxy compound, glycidyl ester epoxy compound, glycidylamine epoxy compound, hydantoin epoxy compound , Isocyanurate-type epoxy compounds, phenol novolak-type epoxy compounds having a triphenolmethane skeleton, and other compounds such as catechol and resorcinol. Diglycidyl ethers of ability phenols, bifunctional alcohols diglycidyl ethers of, and their halides, and the like hydrogenated product. Among these, an epoxy compound having a resorcinol skeleton is preferable from the viewpoint of liquid crystal contamination, and examples thereof include resorcinol diglycidyl ether. The ratio between the epoxy group and the (meth) acryloyl group is not limited, and is appropriately selected from the viewpoint of process compatibility and liquid crystal contamination.
Therefore, a preferred (meth) acrylic compound is a curable compound having a (meth) acryloyl group and further having a resorcinol skeleton, for example, an acrylate of resorcinol diglycidyl ether or a methacrylate of resorcinol diglycidyl ether. is there.

  The content of the component (D) in the liquid crystal sealant of the present invention is usually 30 to 75% by mass, preferably 40 to 65% by mass.

[(E) Imidazole compound]
The liquid crystal sealant of the present invention may contain (E) an imidazole compound (hereinafter, also simply referred to as component (E)).
The imidazole compound is not particularly limited as long as it has an imidazole skeleton in the molecule. In general, the imidazole compound is often used as a curing catalyst for an epoxy compound. However, in the present invention, the imidazole compound has an effect of coexisting with an organic filler and increasing the adhesive strength to an organic film.
Specific examples of the imidazole compound include Cureazole ^RTM 2MZ-H (2-methylimidazole), C11Z (2-undecylimidazole), C17Z (2-heptadecylimidazole), 1,2DMZ (1,2-dimethylimidazole), 2E4MZ (2-ethyl-4-methylimidazole), 2PZ (2-phenylimidazole), 2PZ-PW (2-phenylimidazole), 2P4MZ (2-phenyl-4-methylimidazole), 1B2MZ (1-benzyl-2- Methyl imidazole), 1B2PZ (1-benzyl-2-phenylimidazole), 2MZ-CN (1-cyanoethyl-2-methylimidazole), C11Z-CN (1-cyanoethyl-2-undecylimidazole), 2E4MZ-CN (1 -Cyanoethyl-2 -Ethyl-4-methylimidazole), 2PZ-CN (1-cyanoethyl-2-phenylimidazole), C11Z-CNS (1-cyanoethyl-2-undecylimidazolium trimellitate), 2PZCNS-PW (1-cyanoethyl- 2-phenylimidozolium trimellitate, 2MZ-A (2,4-diamino-6- [2'-methylimidozolyl- (1 ')]-ethyl-s-triazine), C11Z-A (2 4-diamino-6- [2'-undecylimidazolyl- (1 ')] ethyl-s-triazine), 2E4MZ-A (2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1 ′)]-Ethyl-s-triazine), 2MA-OK (2,4-diamino-6- [2′-methylimidozolyl- (1 ′)]-ethyl-s-triazineisocyanu Acid adduct), 2PZ-OK (2-phenylimidazole isocyanuric acid adduct), 2PHZ-PW (2-phenyl-4,5-dihydroxymethylimidazole), 2P4MHZ-PW (2-phenyl-4-methyl-5) Hydroxymethylimidazole), TBZ (2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, SFZ (1-dodecyl-2-methyl-3-benzylimidazolium chloride) (all Shikoku Chemicals Co., Ltd. ), Etc.).
Of these, preferred is an isocyanuric acid adduct of imidazole, and particularly preferred is 2MA-OK (2,4-diamino-6- [2′-methylimidozolyl- (1 ′)]-ethyl-s-triazine isocyanurate. Acid adduct).

  The content of the component (E) in the liquid crystal sealant of the present invention is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, and 0.1 to 3% by mass. .

[(F) Organic filler]
The liquid crystal sealant of the present invention may contain (F) an organic filler (hereinafter, also simply referred to as component (F)). Examples of the (F) organic filler include polyamide fine particles such as nylon 6, nylon 12, and nylon 66, fluorine fine particles such as tetrafluoroethylene and vinylidene fluoride, olefin fine particles such as polyethylene and polypropylene, polyethylene terephthalate, and polyethylene naphthalate. And fine rubber particles such as natural rubber, isoprene rubber and acrylic rubber.

The (F) organic filler is preferably a rubber fine particle. Examples of the rubber fine particles include natural rubber, isoprene rubber, butadiene rubber, styrene / butadiene rubber, butyl rubber, nitrile rubber, ethylene / propylene rubber, chloroprene rubber, acrylic rubber, chlorosulfonated polyethylene rubber, urethane rubber, silicone rubber, and fluoro rubber. And polysulfide rubber, etc., and a single rubber particle may be used, or a core-shell structure using two or more kinds may be used. Also, two or more kinds may be used in combination. Of these, urethane rubber, acrylic rubber, styrene rubber, styrene olefin rubber, or silicone rubber is preferred, and acrylic rubber or silicone rubber is particularly preferred.
When acrylic rubber is used, it is preferably a core-shell acrylic rubber composed of two types of acrylic rubber, and particularly preferably a core layer of n-butyl acrylate and a shell layer of methyl methacrylate. It is sold by Aika Kogyo KK as Zefiac ^RTM F-351.
Examples of the silicone rubber include a crosslinked organopolysiloxane powder and a crosslinked linear dimethylpolysiloxane powder. Examples of the composite silicone rubber include those obtained by coating the surface of the above silicone rubber with a silicone resin (for example, a polyorganosilsesquioxane resin). Of these rubber fine particles, particularly preferred are silicone rubber of linear dimethylpolysiloxane crosslinked powder or composite silicone rubber fine particles of silicone resin-coated linear dimethylpolysiloxane crosslinked powder. These may be used alone or in combination of two or more. Further, the shape of the rubber powder is preferably a spherical shape that does not increase the viscosity after the addition.
Specific examples of the (F) organic filler include KMP594, KMP597, KMP598 (manufactured by Shin-Etsu Chemical Co., Ltd.) and EP2001 (manufactured by Toray Dow Corning Co., Ltd.) as silicone rubber, and JB-800T and HB as urethane rubber. -800BK (Negami Industry Co., Ltd.), and acrylic rubbers as AFX-8 (Sekisui Chemical Co., Ltd.), F351S (Aika Industry Co., Ltd.), W-341, Metablen series (Mitsubishi Rayon Co., Ltd.) Examples of the styrene rubber include the Lavalon series (manufactured by Mitsubishi Chemical Corporation), and examples of the styrene olefin rubber include the TR series (manufactured by JSR Corporation) and the Septon series (Kuraray Co., Ltd.). However, it is not limited to these.
The content of the (F) organic filler in the liquid crystal sealing agent used in the present invention is 5 to 50 parts by mass, preferably 5 to 40 parts by mass, when the total amount of the liquid crystal sealing agent is 100 parts by mass.

In addition, in order to realize the constitution of the present invention, a classification operation is performed on the (F) organic filler to obtain a desired average particle diameter. By performing this operation, coarse particles are also removed, and an (F) organic filler having a sharp particle size distribution can be prepared. It is preferable to perform this classification operation because coarse particles tend to cause a liquid crystal cell gap defect.
The classification operation can be performed, for example, by pulverizing with a jet mill pulverizer JM-0202 (manufactured by Seishin Enterprise) and then using an airflow classifier Crasheal N05 (manufactured by Seishin Enterprise). In order to perform this operation more efficiently, a dispersant or the like may be used.
The median diameter (D50) of the organic filler is preferably from 0.1 to 2.0 μm, and more preferably from 0.1 to 0.5 μm.

[(G) Photo-radical polymerization initiator]
The liquid crystal sealant of the present invention can be used as a liquid crystal sealant of a combined use of light and heat by using the photoradical polymerization initiator (G).
The photo-radical polymerization initiator is not particularly limited as long as it is a compound that generates a radical by irradiation with ultraviolet light or visible light and initiates a chain polymerization reaction.
For example, benzyldimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, diethylthioxanthone, benzophenone, 2-ethylanthraquinone, 2-hydroxy-2-methylpropiophenone, 2-methyl- [4- (methylthio) phenyl] -2- Examples thereof include morpholino-1-propane, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, camphorquinone, 9-fluorenone, and diphenyldisulfide. Specifically, IRGACURE ^RTM 651, 184, 2959, 127, 907, 369, 379EG, 819, 784, 754, 500, OXE01, OXE02, DAROCURE ^RTM 1173, LUCIRIN ^RTM TPO (all manufactured by BASF), Seikeall ^RTM Z, BZ, BEE, BIP, BBI (all manufactured by Seiko Chemical Co., Ltd.) and KAYACURE DETX-S (manufactured by Nippon Kayaku Co., Ltd.).
From the viewpoint of liquid crystal contamination, it is preferable to use a compound having a (meth) acryl group in the molecule. For example, 2-methacryloyloxyethyl isocyanate and 1- [4- (2-hydroxyethoxy) -phenyl]- A reaction product with 2-hydroxy-2-methyl-1-propan-1-one is preferably used. This compound can be produced by the method described in WO 2006/027982.

[(H) inorganic filler]
The liquid crystal sealant of the present invention may contain (H) an inorganic filler. The inorganic filler may be surface-treated with a silane coupling agent or the like. The (H) inorganic filler includes silica, silicon carbide, silicon nitride, boron nitride, calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate, mica, talc, clay, alumina, magnesium oxide, zirconium oxide, aluminum hydroxide, Magnesium hydroxide, calcium silicate, aluminum silicate, lithium aluminum silicate, zirconium silicate, barium titanate, glass fiber, carbon fiber, molybdenum disulfide, asbestos, and the like, preferably fused silica, crystalline silica, silicon nitride, and boron nitride , Calcium carbonate, barium sulfate, calcium sulfate, mica, talc, clay, alumina, aluminum hydroxide, calcium silicate, and aluminum silicate, with silica, alumina and talc being preferred. These inorganic fillers may be used as a mixture of two or more kinds.
If the average particle diameter of the inorganic filler is too large, it may be a failure factor such as not being able to form a gap at the time of bonding the upper and lower glass substrates during the production of a liquid crystal cell with a narrow gap, and thus it is appropriately 2000 nm or less, preferably 1000 nm or less. , More preferably 300 nm or less. A preferred lower limit is about 10 nm, and more preferably about 100 nm. The particle size can be measured with a laser diffraction / scattering type particle size distribution analyzer (dry type) (manufactured by Seishin Enterprise Co., Ltd .; LMS-30).
In the liquid crystal sealant of the present invention, when an inorganic filler is used, it may be about 1 to 30% by mass of the total amount of the liquid crystal sealant, but when the amount is 5% by mass or more, the effect of the present invention is more remarkable. And more preferably 7% by mass or more, particularly preferably 10% by mass or more.

[(I) Thermosetting agent]
The liquid crystal sealant of the present invention may contain (I) a thermosetting agent.
The thermosetting agent means a thermosetting agent which does not generate a radical by heating, unlike the component (B) thermal radical polymerization initiator. Specifically, it reacts nucleophilically with an unshared electron pair or an anion in the molecule, and examples thereof include polyamines, polyphenols, and organic acid hydrazide compounds. However, it is not limited to these. Of these, organic acid hydrazide compounds are particularly preferably used. For example, aromatic hydrazide terephthalic acid dihydrazide, isophthalic acid dihydrazide, 2,6-naphthoic acid dihydrazide, 2,6-pyridine dihydrazide, 1,2,4-benzenetrihydrazide, 1,4,5,8-naphthoic acid Examples thereof include tetrahydrazide and pyromellitic acid tetrahydrazide. In addition, if it is an aliphatic hydrazide compound, for example, formhydrazide, acetohydrazide, propionic hydrazide, oxalic dihydrazide, malonic dihydrazide, succinic dihydrazide, glutaric dihydrazide, adipic dihydrazide, pimelic dihydrazide, sebacic dihydrazide, sebacic dihydrazide 1,4-cyclohexanedihydrazide, tartaric acid dihydrazide, malic acid dihydrazide, iminodiacetic acid dihydrazide, N, N′-hexamethylenebissemicarbazide, citric acid trihydrazide, nitriloacetic acid trihydrazide, cyclohexanetricarboxylic acid trihydrazide, 1,3-bis ( Hydantoin skeleton such as hydrazinocarbonoethyl) -5-isopropylhydantoin, preferably valine hydantoin skeleton (where the carbon atom of the hydantoin ring is iso Dihydrazide compound having a skeleton substituted with a propyl group), tris (1-hydrazinocarbonylmethyl) isocyanurate, tris (2-hydrazinocarbonylethyl) isocyanurate, tris (1-hydrazinocarbonylethyl) isocyanurate, tris (3-hydrazinocarbonylpropyl) isocyanurate, bis (2-hydrazinocarbonylethyl) isocyanurate and the like can be mentioned. From the balance between curing reactivity and latency, preferably isophthalic dihydrazide, malonic dihydrazide, adipic dihydrazide, tris (hydrazinocarbonylmethyl) isocyanurate, tris (1-hydrazinocarbonylethyl) isocyanurate, tris (2- Hydrazinocarbonylethyl) isocyanurate and tris (3-hydrazinocarbonylpropyl) isocyanurate, particularly preferably tris (2-hydrazinocarbonylethyl) isocyanurate.
The component (H) may be used alone, or two or more types may be mixed. When the component (I) is used in the liquid crystal sealant of the present invention, it is usually 0.1 to 10% by mass, preferably 1 to 5% by mass, based on the total amount of the liquid crystal sealant.

[(J) Silane coupling agent]
The liquid crystal sealant of the present invention can improve the adhesive strength and the moisture resistance by adding a silane coupling agent as the component (J).
Component (J) includes 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane Methoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyltrimethoxysilane, 3- Aminopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, vinyltrimethoxysilane, N- (2- (vinylbenzylamino) ethyl) 3-aminopropyltrimethoxysilane hydrochloride, 3-methacryloxypropyltrimethoxysilane, 3-chloropropyl Chill dimethoxysilane, 3-chloropropyl trimethoxy silane, and the like. Since these silane coupling agents are sold by Shin-Etsu Chemical Co., Ltd. as KBM series, KBE series, etc., they can be easily obtained from the market. When the component (J) is used in the liquid crystal sealing agent of the present invention, the amount is preferably 0.05 to 3% by mass based on the total amount of the liquid crystal sealing agent.

[(K) Thiol compound]
The liquid crystal sealant of the present invention can improve the adhesive strength by adding a thiol compound as the component (K).
As the component (K), a compound having two or more, preferably 2 to 6, more preferably 3 to 4 thiol groups (sulfanyl groups) in the molecule can be mentioned.
Examples of the component (K) include the following (1) to (3).
(1) di- or trimercapto C1-C5 alkanes such as methanedithiol, 1,2-dimercaptoethane, 1,2-dimercaptopropane, 2,2-dimercaptopropane, 1,3-dimercaptopropane, , 2,3-trimercaptopropane and the like,
(2) a mercapto C3-C4 acyl group obtained by reacting a trivalent to pentavalent branched C3-C5 alcohol or a dimer thereof with a mercapto C3-C4 fatty acid having a mercapto group at the 2-position or 3-position; Mercapto C3-C4 fatty acid esters having up to six, for example, trimethylolpropane tris (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptopropionate), dipentaerythritol hexakis (3-mercaptopropionate) ), Pentaerythritol tetrakis (3-mercaptobutyrate), etc.
(3) 1,3,5-tris {2- (3-mercapto C2-C5 acyloxy) ethyl} -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, for example, 1 , 3,5-Tris {2- (3-mercaptopropionyloxy) ethyl} -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, 1,3,5-tris ( 3-mercaptobutyloxyethyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione and the like.

These may be used alone or as a mixture of two or more. Among these polythiol compounds, preferred are mercapto C3- having a secondary thiol structure and having 3 to 6 mercapto C3-C4 acyl groups of the above (2) from the viewpoint of liquid crystal contamination and storage stability at room temperature. C4 fatty acid ester or 1,3,5-tris {2- (3-mercaptoC2-C5 acyloxy) ethyl} -1,3,5-triazine-2,4,6 (1H, 3H, 5H) of the above (3) ) -Trione, and more preferably 1,3,5-tris (3-mercaptobutyloxyethyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione or pentane. Erythritol tetrakis (3-mercaptobutyrate) is preferred.
The content of the polythiol compound with respect to the total amount of the liquid crystal sealing agent is usually 0.1 to 10% by mass, preferably 0.3 to 8% by mass, and more preferably 0.5 to 6% by mass.

[Other components]
The liquid crystal sealing agent of the present invention may further contain additives such as a curing accelerator such as an organic acid, a radical polymerization inhibitor, a pigment, a leveling agent, an antifoaming agent, and a solvent, if necessary.
Examples of the curing accelerator include organic acids.
Examples of the organic acid include an organic carboxylic acid and an organic phosphoric acid, and the organic carboxylic acid is preferable. Specifically, aromatic carboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, benzophenonetetracarboxylic acid, furandicarboxylic acid, succinic acid, adipic acid, dodecane diacid, sebacic acid, thiodipropionic acid , Cyclohexanedicarboxylic acid, tris (2-carboxymethyl) isocyanurate, tris (2-carboxyethyl) isocyanurate, tris (2-carboxypropyl) isocyanurate, bis (2-carboxyethyl) isocyanurate and the like. .
When a curing accelerator is used in the liquid crystal sealing agent of the present invention, it is usually 0.1 to 10% by mass, preferably 1 to 5% by mass, based on the total amount of the liquid crystal sealing agent.

The radical polymerization inhibitor is not particularly limited as long as it is a compound that traps radicals generated from a photopolymerization initiator or a thermal radical polymerization initiator and prevents polymerization, and includes quinone, piperidine, and hinder. Dophenol type, nitroso type and the like can be used. Specifically, naphthoquinone, 2-hydroxynaphthoquinone, 2-methylnaphthoquinone, 2-methoxynaphthoquinone, 2,2,6,6-tetramethylpiperidine-1-oxyl, 2,2,6,6-tetramethyl -4-hydroxypiperidine-1-oxyl, 2,2,6,6-tetramethyl-4-methoxypiperidine-1-oxyl, 2,2,6,6-tetramethyl-4-phenoxypiperidine-1- Oxyl, hydroquinone, 2-methylhydroquinone, 2-methoxyhydroquinone, parabenzoquinone, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, 2,6-di-t-butylcresol, stearyl β -(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 2,2'-methylene (4-ethyl-6-t-butylphenol), 4,4'-thiobis-3-methyl-6-t-butylphenol), 4,4'-butylidenebis (3-methyl-6-t-butylphenol), , 9-Bis [1,1-dimethyl-2- [β- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl], 2,4,8,10-tetraoxaspiro [ 5,5] undecane, tetrakis- [methylene-3- (3 ', 5'-di-tert-butyl-4'-hydroxyphenylpropionate) methane, 1,3,5-tris (3', 5'- Di-tert-butyl-4'-hydroxybenzyl) -sec-triazine-2,4,6- (1H, 3H, 5H) trione, paramethoxyphenol, 4-methoxy-1-naphthol, thiodiphenylamine, N-nitroso Examples include, but are not limited to, aluminum salts of phenylhydroxyamine, trade name ADK STAB LA-81, trade name ADK STAB LA-82 (manufactured by Adeka Corporation). Of these, naphthoquinone-based, hydroquinone-based, and nitroso-based piperazine-based radical polymerization inhibitors are preferred, and naphthoquinone, 2-hydroxynaphthoquinone, hydroquinone, 2,6-di-tert-butyl-P-cresol, Polystop 7300P (Hakuto stock) Is preferred, and Polystop 7300P (manufactured by Hakuto Corporation) is most preferred.
The content of the radical polymerization inhibitor is preferably 0.0001 to 1% by mass, more preferably 0.001 to 0.5% by mass, and more preferably 0.01 to 0.2% by mass based on the total amount of the liquid crystal sealing agent of the present invention. Is particularly preferred.

  As an example of a method for obtaining the liquid crystal sealant of the present invention, there is the following method. First, components (C), (D), and (G) are heated and dissolved in component (A) as necessary. Then, after cooling to room temperature, the component (B) is added, and if necessary, the components (E), (F), (H), (I), (J), (K) and an antifoaming agent, a leveling agent, The liquid crystal sealant of the present invention can be produced by adding a solvent or the like, uniformly mixing the mixture with a known mixing device, for example, a three-roll mill, a sand mill, a ball mill or the like, and filtering the mixture with a metal mesh.

The liquid crystal display cell of the present invention is a liquid crystal display cell in which a pair of substrates having predetermined electrodes formed on the substrates are arranged to face each other at a predetermined interval, the periphery thereof is sealed with the liquid crystal sealant of the present invention, and liquid crystal is sealed in the gap. is there. The type of liquid crystal to be enclosed is not particularly limited. Here, the substrate is composed of a combination of at least one of glass, quartz, plastic, silicon, and the like, which has optical transparency. As a manufacturing method, after adding a spacer (gap controlling material) such as glass fiber to the liquid crystal sealing agent of the present invention, the liquid crystal sealing agent is applied to one of the pair of substrates using a dispenser or a screen printing device or the like. After that, if necessary, temporary curing is performed at 80 to 120 ° C. Thereafter, liquid crystal is dropped inside the weir of the liquid crystal sealant, and the other glass substrate is overlaid in a vacuum to form a gap. After forming the gap, the liquid crystal display cell of the present invention can be obtained by curing at 90 to 130 ° C. for 1 to 2 hours. In the case where the liquid crystal sealing agent is used as a light / heat combined type, the liquid crystal sealant is irradiated with ultraviolet rays by an ultraviolet irradiation machine to be photocured. The irradiation amount of ultraviolet rays is preferably 500 to 10000 mJ / cm ² , more preferably 1000 to 6000 mJ / cm ² . Thereafter, if necessary, the composition is cured at 90 to 130 ° C for 1 to 2 hours to obtain the liquid crystal display cell of the present invention. The liquid crystal display cell of the present invention thus obtained has no display failure due to liquid crystal contamination, and has excellent adhesiveness and moisture resistance reliability. Examples of the spacer include glass fiber, silica beads, and polymer beads. The diameter varies depending on the purpose, but is usually 2 to 8 μm, preferably 4 to 7 μm. The amount used is usually 0.1 to 4% by mass, preferably 0.5 to 2% by mass, and more preferably about 0.9 to 1.5% by mass with respect to 100% by mass of the liquid crystal sealant of the present invention. is there.

  The liquid crystal sealant of the present invention has a high adhesive strength to an alignment film, particularly to a photo alignment film. As a result, it is possible to manufacture a high-definition liquid crystal display cell whose quality does not deteriorate over a long period of time. In addition, the cured product is excellent in low liquid crystal contamination, and is also excellent in various cured product characteristics such as moisture resistance and heat resistance. As described above, by using the liquid crystal sealant of the present invention, a liquid crystal display cell having excellent reliability can be realized. Further, the liquid crystal display cell prepared by using the liquid crystal sealant of the present invention satisfies the characteristics required for a liquid crystal display cell such as a high voltage holding ratio and a low ion density.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the examples. Unless otherwise specified, “parts” and “%” in the text are based on mass.

[Synthesis Example 1]
[Synthesis of epoxy compound represented by formula (1)]
(Step 1)
A flask equipped with a thermometer, a cooling pipe, and a stirrer was charged with 316 parts of phenol and 158 parts of resorcinol, heated to 100 ° C., and added with 201 parts of 4,4′-bischloromethylbiphenyl in two hours. Then, the reaction was further performed at the same temperature for 5 hours. Thereafter, the temperature was raised to 160 ° C., and all 4,4′-bischloromethylbiphenyl was reacted. During that time, the generated HCl was distilled off by trapping with an alkali. After completion of the reaction, unreacted phenol and unreacted resorcinol were distilled off at 180 ° C. under reduced pressure using a rotary evaporator to obtain 266 parts of a phenol resin. The hydroxyl equivalent of the obtained phenol resin was 137 g / eq. The softening point was 94 ° C., the ICI viscosity was 470 mPa · s, and the dihydric phenol introduction ratio was 64%.
(Step 2)
To a flask equipped with a stirrer, a reflux condenser, and a stirrer, 266 parts of the phenol resin obtained in the above step 1, 719 parts of epichlorohydrin, 72 parts of methanol, and 21 parts of water were added while performing a nitrogen purge. The temperature was raised to. Next, 83 parts of sodium hydroxide in the form of flakes were added in portions over 90 minutes, and the reaction was further carried out at 75 ° C. for 75 minutes. After the completion of the reaction, water washing was performed, and excess solvent such as epichlorohydrin was distilled off from the organic layer under reduced pressure at 140 ° C. using a rotary evaporator. 750 parts of methyl isobutyl ketone was added to and dissolved in the residue, and the temperature was raised to 75 ° C. After adding 52 parts of a 30% aqueous sodium hydroxide solution with stirring and reacting for 1 hour, the organic layer was washed with water until the washing water became neutral. The obtained organic layer was depressurized at 180 ° C. using a rotary evaporator. A solvent such as methyl isobutyl ketone was distilled off below to obtain 338 parts of an epoxy compound. The epoxy equivalent of the obtained epoxy compound was 209 g / eq. The softening point was 71 ° C., the viscosity at 150 ° C. was 370 mPa · s, and the introduction ratio of the divalent glycidyl-substituted phenyl group was 68%.
The epoxy equivalent was measured by a method described in JIS K-7236, and the softening point was measured by a method in accordance with JIS K-7234.
[Synthesis Example 2]
[Synthesis of fully acrylated bisphenol F epoxy resin]
120.0 g of bisphenol F type epoxy resin (manufactured by Nippon Kayaku Co., Ltd .: RE-602) was dissolved in 122.6 g of toluene, 0.4 g of dibutylhydroxytoluene was added as a polymerization inhibitor, and the temperature was raised to 60 ° C. Then, 63.9 g of acrylic acid equivalent to 100% of the epoxy group was added, the temperature was further raised to 80 ° C., 0.7 g of trimethylammonium chloride as a reaction catalyst was added, and the mixture was stirred at 98 ° C. for about 50 hours. The obtained reaction solution was washed with water, and toluene was distilled off, thereby obtaining 276 g of a fully acrylated bisphenol F type epoxy resin.

[Synthesis Example 3]
[Synthesis of 1,2-bis (trimethylsiloxy) -1,1,2,2-tetraphenylethane]
100 parts (0.28 mol) of commercially available benzopinacol (manufactured by Tokyo Chemical Industry Co., Ltd.) were dissolved in 350 parts of dimethylformaldehyde. To this were added 32 parts (0.4 mol) of pyridine as a base catalyst and 150 parts (0.58 mol) of BSTFA (manufactured by Shin-Etsu Chemical Co., Ltd.) as a silylating agent, and the mixture was heated to 70 ° C. and stirred for 2 hours. The obtained reaction solution was cooled and, with stirring, 200 parts of water was added to precipitate the product and deactivate the unreacted silylating agent. The precipitated product was separated by filtration and washed thoroughly with water. The product obtained was then dissolved in acetone, recrystallized by adding water and purified. As a result, 105.6 parts (yield: 88.3%) of 1,2-bis (trimethylsiloxy) -1,1,2,2-tetraphenylethane were obtained.
As a result of analysis by HPLC (high performance liquid chromatography), the purity was 99.0% (area percentage).

[Preparation of Examples 1-2 and Comparative Examples 1-3]
The epoxy compound (component (A)) represented by the formula (1) and the epoxy compound other than the component (A) (component (C)) were added to the (meth) acrylic compound (component (D)) at the ratios shown in Table 1 below. ) And a photoradical polymerization initiator (component (G)) were added, and the mixture was heated and dissolved at 90 ° C. Cool to room temperature, thermal radical polymerization initiator (component (B)), imidazole compound (component (E)), organic filler (component (F)), inorganic filler (H), thermosetting agent (component (I)) , A silane coupling agent (component (J)), a thiol compound (K), and the like are added, and the mixture is stirred, dispersed with a three-roll mill, filtered through a metal mesh (635 mesh), and used as a sealant for a liquid crystal dropping method ( Examples 1-2 and Comparative Examples 1-3) were prepared.

[Measurement of moisture permeability]
A liquid crystal sealant produced in each of Examples and Comparative Examples was sandwiched between polyethylene terephthalate (PET) films to form a thin film having a thickness of 100 μm. The film was irradiated with ultraviolet rays of 3000 mJ / cm ^{2 by} a UV irradiator, and then put into an oven at 120 ° C. After heat curing for 1 hour, the PET film was peeled off after curing to obtain a sample. Table 1 shows the results of measuring the moisture permeability of the sample at 60 ° C. and 90% with a moisture permeability measuring device (L80-5000, manufactured by Lessy).

[Evaluation of moisture permeability]
○: less than 90 g / m2 · 24 hours ×: 90 g / m2 · 24 hours or more

[Creation of liquid crystal cell for evaluation]
An alignment film liquid (manufactured by JNC: PIA-5540-05A) was applied to the substrate with a transparent electrode, baked, and rubbed. The main seal and the dummy seal were dispensed so that the line width after bonding the obtained liquid crystal sealant to the substrate was 1 mm, and then fine droplets of liquid crystal (JC-5015LA; manufactured by JNC Co., Ltd.) were applied to the seal pattern. It was dropped in the frame. Further, an in-plane spacer (Natco Spacer: KSEB-525F; gap width after bonding: 5 μm) was sprayed on another rubbed substrate, and heat-fixed. And a substrate on which liquid crystal was dropped. After forming a gap by opening to the atmosphere, a mask is applied only to the inside of the seal pattern frame and irradiated with ultraviolet rays of 3000 mJ / cm ^{2 by} a UV irradiator, and then put into an oven and heat-cured at 120 ° C. for 1 hour to form a liquid crystal test cell for evaluation. Created.

[Measurement of voltage holding ratio]
Table 1 shows the results of measuring the voltage holding ratio of the prepared liquid crystal cell for evaluation under the conditions of 5 V, 1 Hz, and 60 ° C. using a liquid crystal physical property evaluation system (Toyo Technica: Model 6254).

[Evaluation of voltage holding ratio]
：: 70% or more Δ: 60% or more and less than 70% X: less than 60%

[Preparation of photo alignment type substrate with alignment film]
A glass substrate was spin-coated with an alignment film solution (RN2880, manufactured by Nissan Chemical Industries, Ltd.), calcined for 3 minutes on a hot plate at 80 ° C., and baked for 30 minutes in an oven at 230 ° C. Further, this substrate with an alignment film was irradiated with ultraviolet rays of 500 mJ / cm ² (measuring wavelength: 254 nm) by a UV irradiator, and further baked in a 230 ° C. oven for 30 minutes.
[Measurement of adhesion strength to photo alignment type substrate with alignment film]
1 g of 5 μm glass fiber as a spacer is added to 100 g of the liquid crystal sealant manufactured in the example and the comparative example, and the mixture is stirred. This liquid crystal sealant is applied on a glass substrate of 15 mm × 30 mm, and a glass substrate of 15 mm × 30 mm is bonded on the liquid crystal sealant and irradiated with ultraviolet rays of 3000 mJ / cm 2 by a UV irradiator. The composition was thermally cured at a temperature of 1 hour. Table 1 shows the results of measuring the peel strength of the glass substrate with a bond tester (SS-30WD, manufactured by Seishin Shoji Co., Ltd.).

[Evaluation of adhesive strength]
○: 8 kg or more △: 6 kg or more and less than 8 kg ×: less than 6 kg

  From the results shown in Table 1, the liquid crystal sealant of the present invention containing the compound represented by the formula (1) has high adhesive strength to an organic film, low contamination to liquid crystal, and low moisture permeability. confirmed. That is, the liquid crystal sealant of the present invention is very useful for manufacturing a highly reliable liquid crystal display cell.

  The effect of the liquid crystal sealant of the present invention on the liquid crystal display characteristics is extremely small, so that the liquid crystal display element can have high definition, high speed response, low voltage drive, and long life. Further, since the adhesive strength and the moisture resistance reliability are excellent, a highly reliable liquid crystal display element can be manufactured.

Claims (17)

A liquid crystal sealing agent for a liquid crystal dropping method, comprising (A) an epoxy compound represented by the following formula (1), and (B) a thermal radical polymerization initiator ,
A liquid crystal sealing agent for a liquid crystal dropping method, wherein the content of the (B) thermal radical polymerization initiator is 0.001 to 3% by mass based on the total amount of the liquid crystal sealing agent for a liquid crystal dropping method.

(In the formula, n represents an average degree of polymerization and is a positive number of 1 to 10. A plurality of Rs each independently represent a hydrogen atom or a group represented by the following formula (2).

The wavy line in the equation (2) indicates the bonding position. ) The liquid crystal sealant according to claim 1, wherein the component (A) is an epoxy compound represented by the following formula (3).

(In the formula, m represents an average degree of polymerization and is a positive number of 1 to 10. A plurality of Ss independently represent a hydrogen atom or a group represented by the following formula (4).

The middle dashed line in the equation (4) indicates the bonding position. )   The said component (B) is a thermal radical polymerization initiator which does not contain an oxygen-oxygen bond (-OO-) and a nitrogen-nitrogen bond (-N = N-) in a molecule. Liquid crystal sealant for liquid crystal dropping method.   The liquid crystal sealing agent for a liquid crystal dropping method according to any one of claims 1 to 3, further comprising an epoxy compound other than the component (A) (C).   The liquid crystal sealant for a liquid crystal dropping method according to any one of claims 1 to 4, further comprising (D) a (meth) acrylic compound.   The liquid crystal sealant for a liquid crystal dropping method according to any one of claims 1 to 5, further comprising (E) an imidazole compound.   The liquid crystal seal for a liquid crystal dropping method according to claim 6, wherein the component (E) is a 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine isocyanuric acid adduct. Agent.   The liquid crystal sealant for a liquid crystal dropping method according to any one of claims 1 to 7, further comprising (F) an organic filler.   9. The composition according to claim 1, wherein the component (F) is one or more organic fillers selected from the group consisting of urethane fine particles, acrylic fine particles, styrene fine particles, styrene olefin fine particles, and silicone fine particles. The liquid crystal sealant for liquid crystal dropping method according to the above.   The liquid crystal sealant for a liquid crystal dropping method according to any one of claims 1 to 9, further comprising (G) a photoradical polymerization initiator.   The liquid crystal sealant for a liquid crystal dropping method according to any one of claims 1 to 10, further comprising (H) an inorganic filler.   The liquid crystal sealing agent for a liquid crystal dropping method according to any one of claims 1 to 11, further comprising (I) a thermosetting agent.   The liquid crystal sealant for a liquid crystal dropping method according to claim 12, wherein the component (I) is an organic acid hydrazide.   The liquid crystal sealing agent for a liquid crystal dropping method according to any one of claims 1 to 13, further comprising (J) a silane coupling agent.   The liquid crystal sealant according to any one of claims 1 to 14, further comprising (K) a thiol compound.   In a liquid crystal display cell composed of two substrates, after a liquid crystal is dropped inside the weir of the liquid crystal sealing agent for a liquid crystal dropping method according to any one of claims 1 to 15 formed on one substrate. And a method of manufacturing a liquid crystal display cell, wherein the other substrate is bonded and then cured by light and / or heat.   A liquid crystal display cell sealed with a cured product obtained by curing the liquid crystal sealant for a liquid crystal dropping method according to claim 1.