KR20140047081A

KR20140047081A - Liquid crystal sealant and liquid crystal display cell using same

Info

Publication number: KR20140047081A
Application number: KR1020147001511A
Authority: KR
Inventors: 나오미 하스미; 마사노리 하시모토; 겐타 스가와라; 마키에 소네
Original assignee: 닛뽄 가야쿠 가부시키가이샤
Priority date: 2011-07-13
Filing date: 2012-07-12
Publication date: 2014-04-21
Also published as: JP6231230B2; TWI543992B; KR101885944B1; TW201319092A; WO2013008884A1; CN106397697A; JPWO2013008884A1; CN103649825B; JP6092103B2; CN103649825A; JP2017083899A

Abstract

Since the reaction by heat is fast, it provides the liquid crystal sealing agent for liquid crystal dropping methods which is very low in contamination with respect to a liquid crystal through a process, and excellent in handling property and storage stability. The liquid crystal sealing agent for liquid crystal dropping methods of this invention is a (a) thermal radical polymerization initiator which does not have an oxygen-oxygen bond (-OO-) and a nitrogen-nitrogen bond (-N = N-) in a molecule | numerator, (b) radical It contains a polymerization inhibitor and (c) curable resin which has a (meth) acryloyl group.

Description

Liquid crystal sealing agent and liquid crystal display cell using the same {LIQUID CRYSTAL SEALANT AND LIQUID CRYSTAL DISPLAY CELL USING SAME}

The present invention relates to a liquid crystal sealing agent for a liquid crystal dropping method that can be cured by heat. More specifically, it is related with the liquid crystal sealing agent for liquid crystal dropping methods which has favorable curability by heat, and also excellent hardened | cured material characteristics, such as handling property, storage stability, and adhesive strength, its manufacturing method, and its hardened | cured material.

Background Art [0002] Along with the recent enlargement of a liquid crystal display cell, a so-called liquid crystal dropping method has been proposed as a method of manufacturing a liquid crystal display cell (Patent Documents 1 and 2). It is a manufacturing method of the liquid crystal display cell in which a liquid crystal is sealed by bonding a different board | substrate after dripping a liquid crystal specifically inside the bank of the liquid crystal sealing agent formed in one board | substrate.

However, in the liquid crystal dropping method, since the liquid crystal sealing agent in an uncured state contacts the liquid crystal, the components of the liquid crystal sealing agent are dissolved (elution) in the liquid crystal at that time, thereby lowering the resistance value of the liquid crystal and generating display defects near the seal. There is a problem.

In order to solve this subject, the thing of a light-heat combined use type is currently used as a liquid crystal sealing agent for liquid crystal dropping methods, and is put to practical use (patent document 3, 4). In the liquid crystal dropping method using this liquid crystal sealing agent, it is characterized by irradiating light to the liquid crystal sealing agent inserted in the board | substrate and hardening it first, and then heating and making it secondary harden. According to this method, an uncured liquid crystal sealing agent can be hardened quickly by light, and it is possible to suppress the dissolution (elution) of the liquid crystal sealing agent component to the liquid crystal. In addition, the photocuring alone also causes a problem of insufficient adhesive strength due to curing shrinkage or the like during photocuring. However, in the case of the photothermal combined use type, such a problem can be solved by secondary curing by heating.

However, in recent years, with the miniaturization of liquid crystal display elements, light shielding portions where light does not reach the liquid crystal sealing agent are generated by the metal wiring portions of the array substrates of the liquid crystal display elements and the black matrix portions of the color filter substrates. The problem of failure is becoming more serious than before. That is, due to the presence of the light-shielding portion, the primary curing by the light becomes insufficient, and a large amount of uncured components remains in the liquid crystal sealant. In this state, when the heat proceeds to the secondary curing step, the dissolution of the uncured component into the liquid crystal results in the fact that it is promoted by the heat, causing display defects near the seal.

In order to solve this problem, a proposal has been made to increase the curing rate by heat to reduce component dissolution by using a thermal radical generator, and furthermore, a proposal to realize the liquid crystal dropping method only by heat by applying this technique. (Patent Documents 5 and 6) are also made. However, at present, an organic peroxide or an azo compound is used as a thermal radical generating agent, and when these radicals are generated by heating, they generate nitrogen, oxygen, or the like, generate bubbles in the cured product, and lower the adhesive strength. The problem is that the cargo properties are lowered.

Moreover, the said method becomes a problem that the handling property is low because of the quick reaction. Handling property means the ease of use of a liquid crystal sealing agent. For example, there is a phenomenon that the liquid crystal sealing agent is cured or gelated in a process of being placed under vacuum or applying heat, such as a defoaming step of a liquid crystal sealing agent or a mixing step of a spacer agent, and in this application, Ease of occurrence is defined as handling. Therefore, the thing which is hard to cause gelation is made into the liquid crystal sealing agent with good handling property, and the thing which is easy to cause gelation is made into the liquid crystal sealing agent with poor handling property.

In addition, apart from the handling properties, storage stability is also an important characteristic of the liquid crystal sealing agent. This is a property which seal | sticker becomes difficult by the viscosity increase in room temperature, and the liquid-crystal sealing agent using a thermal radical generating agent is inferior to this storage stability. Although the method of solving this subject is proposed in patent document 7, it is not enough as what solves all the said subjects.

As described above, although the development of the liquid crystal sealing agent for a liquid crystal dropping method is being carried out very energetically, while having excellent heat reactivity and light-shielding part hardenability, it is compatible with handling property, storage stability, etc. Liquid crystal sealing agent which is excellent also in the characteristic is not yet implemented.

Japanese Patent Application Laid-Open No. 63-179323 Japanese Patent Laid-Open No. 10-239694 Patent Publication No.3583326 Japanese Laid-Open Patent Publication No. 2004-61925 Japanese Patent Application Laid-Open No. 2004-126211 Japanese Laid-Open Patent Publication No. 2009-8754 Japanese Unexamined Patent Publication No. 2009-42409

After dropping a liquid crystal inside the bank of the liquid crystal sealing agent formed in one board | substrate, this invention bonds another board | substrate, and hardens a liquid crystal sealing agent part only by heating or combined use with light heat, The present invention relates to a liquid crystal sealing agent used in a liquid crystal dropping method for producing a display cell, and because the reaction by heat is fast, very low contamination to the liquid crystal through the process, and excellent handling properties such as defoaming, and other substrates Since it is excellent in the coating property, adhesiveness, adhesive strength, etc. with respect to, the liquid crystal sealing agent which can be adapted to the liquid crystal panel of any design is proposed.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining, as for the liquid crystal sealing agent which uses a specific thermal radical polymerization initiator and a radical polymerization inhibitor together, the said thermal reactivity and handling property are compatible, As a result, it can also suppress liquid-crystal contamination, Furthermore, adhesive strength It discovered that the hardened | cured material characteristics, such as these, were also excellent and came to complete this invention.

That is, this invention relates to following (1)-(12). In addition, in this specification, "(meth) acryl" means one or both of "acryl" and "methacryl". Similarly, in this specification, "(meth) acryloyl" means the one or both of "acryloyl" and "methacryloyl".

(One)

(a) a thermal radical polymerization initiator that does not have an oxygen-oxygen bond (-OO-) and a nitrogen-nitrogen bond (-N = N-) in the molecule, (b) a radical polymerization inhibitor, and (c) a (meth) acryl It contains curable resin which has a diary, The liquid crystal sealing agent for liquid crystal dropping methods.

(2)

Liquid crystal sealing agent for liquid crystal dropping methods as described in said (1) whose said component (a) is a compound represented by following formula (1).

[Chemical Formula 1]

[In formula (1), Y <^1> , Y <^2>. Each independently represents a hydrogen atom, a phenyl group, or a silicon atom, and R ¹ to R ⁶ Each independently represents a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms, and X ¹ to X ⁴ Each independently represents a hydrogen atom, a methyl group, an ethyl group, a methoxy group, an ethoxy group, a phenoxy group, or a halogen atom. Provided that R ¹ to R ³ or R ⁴ to R ⁶ bonded to Y ¹ or Y ² , respectively; Silver, Y ¹ or Y ² Is not a hydrogen atom.]

(3)

Liquid crystal sealing agent for dripping methods as described in said (1) or (2) whose said component (b) is 1 or 2 or more radical polymerization inhibitor chosen from following formula (2)-(4).

(2)

[In formula (2), R ⁷ Represents a hydrogen atom, a hydroxyl group, a linear or branched alkoxy group having 1 to 4 carbon atoms, or a linear or branched alkyl group having 1 to 4 carbon atoms.]

(3)

[In formula (3), R ⁸ Silver hydrogen atom, hydroxyl group, C1-C4 linear or branched alkoxy group, phenoxy group, acetamide group (-NHCOCH ₃ ), amino group (-NH ₂ ), carboxyl group (-COOH), cyano group (-CN ), A benzoyloxy group (-OCOC ₆ H ₅ ), an isothiocyanate group (-NCS), or an oxo group (= O), and R ⁹ to R ¹² Each independently represents a linear or branched alkyl group having 1 to 4 carbon atoms.]

[Chemical Formula 4]

[In formula (4), R ¹³ Represents a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms.]

(4)

Furthermore, the liquid crystal sealing agent for liquid crystal dropping methods in any one of said (1)-(3) containing curable resin which has (d) epoxy group, and (e) thermosetting agent.

(5)

Liquid crystal sealing agent for liquid crystal dropping methods as described in said (4) whose said component (e) is organic acid hydrazide.

(6)

Furthermore, the liquid crystal sealing agent for liquid crystal dropping methods in any one of said (1)-(5) containing (f) silane coupling agent.

(7)

Furthermore, the liquid crystal sealing agent for liquid crystal dropping methods in any one of said (1)-(6) containing (g) inorganic filler.

(8)

Furthermore, the liquid crystal sealing agent for liquid crystal dropping methods in any one of said (1)-(7) containing (h) photoinitiator.

(9)

When the total amount of the component (c) and the component (d) is 100 parts by mass, the liquid crystal sealing for the liquid crystal dropping method according to the above (4) or (5), wherein the content of the component (b) is 0.0001 to 1 part by mass. My.

(10)

The manufacturing method of the liquid crystal sealing agent for liquid crystal dropping methods in any one of said (1)-(9) containing the process of melt | dissolving the said component (b) with respect to the said component (c).

(11)

The manufacturing method of the liquid crystal sealing compound for liquid crystal dropping methods as described in said (4) or (5) containing the process of melt | dissolving the said component (b) with respect to the said component (d).

(12)

When obtained by hardening the liquid crystal sealing agent for liquid crystal dropping methods in any one of said (1)-(9), or the liquid crystal sealing agent for liquid crystal dropping methods obtained by the manufacturing method as described in said (10) or (11). Liquid crystal display cell sealed with cargo.

Since the hardening rate at the time of thermosetting is high, the liquid crystal sealing agent of this invention is applicable to the liquid crystal dropping method which hardens a liquid crystal sealing agent only by heat. Moreover, also in the light-heat combined use liquid crystal dropping method, it has sufficient sclerosis | hardenability also under the wiring hard to reach | attain light, for this reason, the freedom degree of the wiring design of a panel can be ensured, and manufacture of a highly reliable liquid crystal display panel easily is carried out. can do.

The thermal radical polymerization initiator which does not have an oxygen-oxygen bond (-OO-) and a nitrogen-nitrogen bond (-N = N-) in (a) molecule used in this invention generates a radical by heating, and Although it will not specifically limit, if it is a compound which starts a polymerization reaction, A benzoin, benzoin ether, acetophenone, benzo pinacol can be mentioned. Especially, the compound represented by said Formula (1) is used especially preferably from a viewpoint of reactivity or the solubility to a liquid crystal.

In the formula (1), Y ¹ and Y ² Each independently represents a hydrogen atom, a phenyl group, or a silicon atom, and at least one is preferably a silicon atom. In the formula ^(1), R 1 ~ (hereinafter also referred to as simply an alkyl group C1 ~ C4) R ⁶ carbon atoms, straight-chain or branched alkyl group of 1 to 4, in the Examples, such as methyl, ethyl, n- propyl, i- Propyl, t-butyl, etc. are mentioned. Moreover, as a halogen in X <^1> -X <^4> , a fluorine atom, a chlorine atom, a bromine atom, etc. are mentioned.

Y ¹ or Y ² of formula (1) When is other than a hydrogen atom, R ¹ R ² R ³ Y ¹ -or R ⁴ R ⁵ R ⁶ Y ² -is a phenyl group, a phenyl group substituted with 1 to 3 C1 to C4 alkyl groups, a di C1 to C4 alkylsilyl group Or a tri C1 to C4 alkylsilyl group, more preferably a di C1 to C4 alkylsilyl group or a tri C1 to C4 alkylsilyl group, and more preferably a tri C1 to C4 alkylsilyl group.

In the di or tri C1 to C4 linear or branched alkylsilyl group in R ¹ R ² R ³ Y ^1- , R ⁴ R ⁵ R ⁶ Y ² -of the formula (1), two or three C1 to C4 The alkyl group may be the same or different. As the silyl group, for example, di C1 to C4 alkylsilyl groups such as dimethylsilyl, diethylsilyl and methylethylsilyl; tri C1 to trimethylsilyl, triethylsilyl, dimethylethylsilyl and t-butyldimethylsilyl; C4 alkylsilyl group; These are mentioned. Among them, a tri-C1-C4 alkylsilyl group is most preferable, and a trimethylsilyl group is more preferable.

X ¹ to X ^{4 in} formula (1) Each independently represents a hydrogen atom, a methyl group, an ethyl group, a methoxy group, an ethoxy group, a phenoxy group, or a halogen atom, and preferably X ¹ to X ⁴ Is the case where all are hydrogen atoms.

Specific examples of the compound represented by the formula (1) include benzopinacol, 1,2-dimethoxy-1,1,2,2-tetraphenylethane, 1,2-diethoxy-1,1,2,2 Tetraphenyl ethane, 1,2-diphenoxy-1,1,2,2-tetraphenyl ethane, 1,2-dimethoxy-1,1,2,2-tetra (4-methylphenyl) 2-diphenoxy-1,1,2,2-tetra (4-methoxyphenyl) ethane, 1,2-bis (trimethylsiloxy) -1,1,2,2-tetraphenylethane, Bis (t-butyldimethylsiloxy) -1,1,2,2-tetraphenylethane, 1-hydroxycyclohexylmethane-bis 2-trimethylsiloxy-1,1,2,2-tetraphenylethane, 1-hydroxy-2-triethylsiloxy-1,1,2,2-tetraphenylethane, 1-hydroxy- -t-butyldimethylsiloxy-1,1,2,2-tetraphenylethane and the like, 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, 1,2-bis (trimethylsiloxy) -1,1,2,2-tetraphenylethane, more preferably 1-hydroxy-2-trimethylsiloxy -1,1,2,2-tetraphenylethane and 1,2-bis (trimethylsiloxy) -1,1,2,2-tetraphenylethane. However, as long as it has a structure of Formula (1), it is not limited to these compounds. Moreover, it is also possible to use 2 or more types together.

Among the thermal radical polymerization initiators, benzopinacol is commercially available from Tokyo Chemical Industry Co., Ltd., Wako Junyaku Industry Co., Ltd., and the like. Moreover, what etherified the hydroxyl group of benzopinacol can be easily synthesized by a well-known method. Moreover, what silyl-etherylated the hydroxy group of benzo pinacol can synthesize | combine and obtain by the method of heating the corresponding benzo pinacol and various silylating agents under basic catalysts, such as a pyridine.

Examples of the silylating agent include trimethylchlorosilane (TMCS), hexamethyldisilazane (HMDS), N, O-bis (trimethylsilyl) trifluoroacetamide (BSTFA), which are generally known trimethylsilylating agents, and triethylsilyl. Triethylchlorosilane (TECS) which is an agent, t-butylmethylsilane (TBMS) which is a t-butyldimethylsilylating agent, etc. are mentioned. These reagents are readily available on the market such as silicone derivative makers. As reaction amount of a silylating agent, 1.0-5.0 times mole is preferable with respect to 1 mol of hydroxyl groups of a target compound. More preferably 1.5 to 3.0 times by mol. Less than 1.0 molar mole leads to poor reaction efficiency and longer reaction time, thereby promoting pyrolysis. If the molar amount is more than 5.0 moles, the separation becomes poor at the time of recovery, or the purification becomes difficult.

Pyridine, triethylamine, etc. are mentioned as a basic catalyst. A basic catalyst has the effect of trapping hydrogen chloride generated at the time of reaction, keeping the reaction system under basic, and extracting hydrogen of a hydroxyl group, and promoting reaction more. As content, what is necessary is just 0.5 mol or more with respect to the target hydroxyl group, and you may use as a solvent.

As the solvent, nonpolar organic solvents such as hexane, ether, and toluene are excellent because they do not participate in the reaction. In addition, polar solvents such as pyridine, dimethylformaldehyde (DMF), dimethyl sulfoxide (DMSO), tetrahydrofuran (THF) and acetonitrile are also preferable. As content, the extent to which the mass concentration of a solute becomes 5-40 mass% is preferable. More preferably, it is 10-30 mass%. If the content of the solvent is too small, the reaction is slow, and the decomposition by heat is promoted, resulting in a drop in yield. On the contrary, too many products are produced and the yield is lowered.

It is preferable that the (a) thermal radical polymerization initiator used by this invention makes a particle size fine and disperse | distributes uniformly. 5 micrometers or less are preferable, since the average particle diameter becomes a bad factor, such as gap formation at the time of bonding up-and-down glass substrates at the time of manufacture of a liquid crystal display cell of a narrow gap, when it is too large, and it is more preferable. 3 micrometers or less. Moreover, although it does not interfere even if it makes it fine without limitation, Usually, a minimum is about 0.1 micrometer. The particle size can be measured by a laser diffraction / scattering type particle size distribution analyzer (dry type) (LMS-30, manufactured by Seishin Co., Ltd.).

As content of this thermal radical polymerization initiator, when the whole curable resin of the liquid crystal sealing agent of this invention is 100 mass parts, it is preferable that it is 0.0001-10 mass parts, More preferably, it is 0.0005-5 mass parts, 0.001-3 mass Particularly preferred. In addition, curable resin represents (c) component and (d) component in the case of containing as needed. In this application, it is the same below.

Moreover, the component (b) radical polymerization inhibitor used in this invention will not be specifically limited if it is a compound which reacts with the radical which generate | occur | produces from a radical polymerization initiator or the said curable resin monomer, and prevents polymerization, A quinone system and a piperidine system , Hindered phenol 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, stearylβ- (3,5-dit-butyl-4-hydroxyphenyl) propionate, 2,2 '-Methylenebis (4-ethyl-6-t-butylphenol), 4,4'-thiobis-3-methyl-6-t-butylphenol), 4,4'-butylidenebis (3-methyl -6-t-butylphenol), 3,9-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-t-butyl-4'-hydroxy Nylpropionate) methane, 1,3,5-tris (3 ', 5'-di-t-butyl-4'-hydroxybenzyl) -sec-triazine-2,4,6- (1H, 3H , 5H) trione, paramethoxyphenol, 4-methoxy-1-naphthol, thiodiphenylamine, aluminum salt of N-nitrosophenylhydroxyamine, trade name adecastab LA-81, trade name adecastab LA -82 (manufactured by Adeka Corporation) and the like, but are not limited to these.

Among these, it is a radical polymerization inhibitor as described in said Formula (2)-(4) which exhibits the effect remarkably in combination with the said thermal radical polymerization initiator. These radical polymerization inhibitors may be used independently and may use 2 or more types together.

In addition, R <^8> in the said Formula (3) Silver, a hydrogen atom, a hydroxyl group, a linear or branched alkoxy group having 1 to 4 carbon atoms, a phenoxy group, acetamide group (-NHCOCH ₃ ), amino group (-NH ₂ ), carboxyl group (-COOH), cyano group (- CN), a benzoyloxy group (-OCOC ₆ H ₅ ), an isothiocyanate group (-NCS), or an oxo group (= O) is represented, Preferably a hydrogen atom, a hydroxyl group, C1-C4 straight It is a chain or branched alkoxy group, a phenoxy group, an amino group, and a carboxyl group, More preferably, they are a hydrogen atom, a hydroxyl group, an amino group, and a carboxyl group, Especially preferably, they are a hydrogen atom and a hydroxyl group.

Component (b) radical polymerization inhibitor is a method of adding when synthesize | combining curable resin which has a component (c) (meth) acryloyl group, curable resin and component (d) which have a component (c) (meth) acryloyl group ) There is a method of adding and dissolving one or both of the curable resins having an epoxy group, and in order to obtain a more effective effect, the curable resin having component (c) (meth) acryloyl group and curable component (d) epoxy group It is more preferable to add and dissolve to one or both of the resins.

(b) As content of radical polymerization inhibitor, when the whole curable resin in the liquid crystal sealing agent of this invention is 100 mass parts, 0.0001-1 mass part is preferable, 0.001-0.5 mass part is more preferable, 0.01-0.2 mass part Particularly preferred. When there are too few radical polymerization inhibitors, sufficient handling property may not be obtained, and when too much, the liquid-crystal contamination by delay of thermal reaction may become a problem.

The liquid crystal sealing agent of this invention contains curable resin which has a component (c) (meth) acryloyl group. As such curable resin, (meth) acrylic ester, an epoxy (meth) acrylate, etc. are mentioned, for example. As (meth) acrylic ester, benzyl methacrylate, cyclohexyl methacrylate, glycerol dimethacrylate, glycerol triacrylate, EO modified glycerol triacrylate, pentaerythritol acrylate, trimethylol propane triacrylate, tris (Acryloxyethyl) isocyanurate, dipentaerythritol hexaacrylate, a phloroglycinol triacrylate, etc. are mentioned. The epoxy (meth) acrylate is obtained by a known method by the reaction of an epoxy resin with (meth) acrylic acid. Although it does not specifically limit as an epoxy resin used as a raw material, A bifunctional or more functional epoxy resin is preferable, For example, a bisphenol-A epoxy resin, a bisphenol F-type epoxy resin, a bisphenol S-type epoxy resin, a phenol novolak-type epoxy resin, Cresol novolac epoxy resin, bisphenol A novolac epoxy resin, bisphenol F novolac epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, glycidyl ester epoxy resin, glycidylamine epoxy resin, Hydantoin type epoxy resin, isocyanurate type epoxy resin, the phenol novolak type epoxy resin which has a triphenol methane frame | skeleton, diglycidyl etherate of bifunctional phenols, such as catechol and resorcinol, 2 Diglycidyl ether compounds of functional alcohols, and their halides, hydrogenated substances and the like. Among them, resorcin diglycidyl ether is more preferable from the viewpoint of liquid crystal contamination. Moreover, the ratio of an epoxy group and a (meth) acryloyl group is not limited, It selects suitably from a viewpoint of process suitability and liquid-crystal contamination.

Moreover, (c) As content rate which occupies in the liquid crystal sealing agent for liquid crystal dropping methods of curable resin which has a (meth) acryloyl group, when making the total amount of liquid crystal sealing agent 100 mass parts, it is preferable to exist in the range of 30-90 mass parts. More preferably, it is about 50-90 mass parts.

In the liquid crystal sealing agent for liquid crystal dropping methods of this invention, adhesive strength improvement can be aimed at by using curable resin which has a component (d) epoxy group further. Although it does not specifically limit as curable resin which has an epoxy group used, Bifunctional or more than two functional epoxy resins are preferable, For example, bisphenol-A epoxy resin, bisphenol F-type epoxy resin, bisphenol S-type epoxy resin, phenol novolak-type epoxy Resins, cresol novolac epoxy resin, bisphenol A novolac epoxy resin, bisphenol F novolac epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, glycidyl ester epoxy resin, glycidylamine epoxy Diglycidyl ether compounds of resins, hydantoin type epoxy resins, isocyanurate type epoxy resins, phenol novolac type epoxy resins having a triphenol methane skeleton, bifunctional phenols, and diglycides of difunctional alcohols Cyl ether ethers, their halides, hydrogenated substances and the like. Among these, bisphenol-type epoxy resins and novolak-type epoxy resins are preferable from the viewpoint of liquid crystal contamination. Content in the liquid crystal sealing agent of curable resin which has a component (d) epoxy group is about 1-30 mass parts, when the total amount of liquid crystal sealing agent is 100 mass parts.

As a liquid crystal sealing agent for liquid crystal dropping methods of this invention, the thermosetting agent which is a component (e) used with a component (d) is not specifically limited, Although a polyhydric amine, a polyhydric phenol, a hydrazide compound, etc. are mentioned, it is a solid Organic acid hydrazide of is particularly preferably used. For example, salicylic acid hydrazide, benzoic acid hydrazide, 1-naphthoic acid hydrazide, terephthalic acid dihydrazide, isophthalic acid dihydrazide, 2,6-naphthoic acid dihydride which are aromatic hydrazides. Drazide, 2,6-pyridine dihydrazide, 1,2,4-benzenetrihydrazide, 1,4,5,8-naphthoate tetrahydrazide, pyromellitic acid tetrahydrazide, etc. Can be mentioned. Moreover, if it is an aliphatic hydrazide compound, For example, form hydrazide, acethydrazide, propionic acid hydrazide, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydride, for example. Dragizide, adipic dihydrazide, pimelic acid dihydrazide, sebacic acid dihydrazide, 1,4-cyclohexanedihydrazide, tartaric acid dihydrazide, malic acid dihydrazide, imino diacetic acid di Hydrazide, N, N'-hexamethylenebissemicarbazide, citric acid trihydrazide, nitriloacetic acid trihydrazide, cyclohexanetricarboxylic acid trihydrazide, 1,3-bis (hydra Dihi having a hydantoin skeleton, such as ginocarbonoethyl) -5-isopropylhydantoin, preferably a valinhydantoin skeleton (skeleton in which the carbon atom of the hydantoin ring is substituted with an isopropyl group) Drazide compound, tris (1-hydrazinocarbonylmethyl) isocyanurate, tris (2-hydrazinocarbonylethyl) isocyanurate, tris (2-hydrazinocarbonylethyl) isocyanurate And lates, tris (3-hydrazinocarbonylpropyl) isocyanurate, bis (2-hydrazinocarbonylethyl) isocyanurate, and the like. These thermosetting agents may be used alone or in combination of two or more thereof. In the balance of curing reactivity and latentness, isophthalic acid dihydrazide, malonic acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, tris (1-hydrazinocarbonylmethyl) iso Cyanurate, tris (2-hydrazinocarbonylethyl) isocyanurate, tris (2-hydrazinocarbonylethyl) isocyanurate, tris (3-hydrazinocarbonylpropyl) isocyanur It is a rate, Especially preferably, it is malonic acid dihydrazide and sebacic acid dihydrazide. As a usage-amount in the case of using such a (e) thermosetting agent, when the epoxy equivalent of the epoxy group of curable resin which has an epoxy group of component (d) is 1, it is 0.5-2.0 equivalent, Preferably it is 0.8-1.2 equivalent.

In the liquid crystal sealing agent for liquid crystal dropping methods of this invention, adhesive strength improvement and moisture resistance reliability improvement can be aimed at using a component (f) silane coupling agent. Examples of the silane coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl Aminopropyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyltrimethoxysilane, N- Aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, vinyltrimethoxysilane, N- (2- (vinylbenzylamino) ethyl) 3-aminopropyltrimethoxysilane hydrochloride, 3-methacryloxypropyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, and the like. (f) When content which occupies for the liquid crystal sealing agent of a silane coupling agent makes the whole liquid crystal sealing agent of this invention 100 mass parts, 0.05-3 mass parts is preferable.

In the liquid crystal sealing agent for liquid crystal dropping methods of this invention, adhesive strength improvement and moisture resistance reliability improvement can be aimed at using a component (g) inorganic filler. As the component (g) inorganic filler, fused silica, crystalline silica, silicon carbide, silicon nitride, boron nitride, calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate, mica, talc, clay, alumina, magnesium oxide, zirconium oxide, hydroxide Aluminum, magnesium hydroxide, calcium silicate, aluminum silicate, lithium aluminum silicate, zirconium silicate, barium titanate, glass fiber, carbon fiber, molybdenum disulfide, asbestos and the like, and preferably fused silica, crystalline silica, silicon nitride, and nitride Boron, calcium carbonate, barium sulfate, calcium sulfate, mica, talc, clay, alumina, aluminum hydroxide, calcium silicate, aluminum silicate, more preferably fused silica, crystalline silica, alumina, talc. These inorganic fillers may be used by mixing two or more kinds. 3 micrometers or less are suitable, since the average particle diameter becomes a bad factor, such as the gap formation at the time of bonding of the upper and lower glass substrates at the time of manufacturing a narrow gap liquid crystal cell, when it is too large, it is suitable, Preferably it is 2 micrometers or less to be. The particle size can be measured by a laser diffraction / scattering type particle size distribution analyzer (dry type) (LMS-30, manufactured by Seishin Co., Ltd.).

Content in the liquid crystal sealing agent of the inorganic filler (g) which can be used by the liquid crystal sealing agent of this invention is 1-60 mass parts normally, when the total amount of the liquid crystal sealing agent of this invention is 100 mass parts, Preferably it is 1 It is-40 mass parts. When content of an inorganic filler is too small, since the adhesive strength with respect to a glass substrate falls, and since moisture resistance reliability is inferior, the fall of the adhesive strength after moisture absorption may also become large. On the other hand, when there is too much content of an inorganic filler, it may not be crushed well and the gap formation of a liquid crystal cell may become impossible.

The liquid crystal sealing agent for liquid crystal dropping methods of this invention may contain a component (h) photoinitiator, in order to make it the curable liquid crystal sealing compound for light heat combination. Although a photoinitiator will not be specifically limited if it is a compound which generate | occur | produces a radical by irradiation of UV and visible light, and starts a chain polymerization reaction, For example, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, diethyl Thioxanthone, benzophenone, 2-ethylanthraquinone, 2-hydroxy-2-methylpropiophenone, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propane, 2 And 4,6-trimethylbenzoyldiphenylphosphine oxide. Moreover, it is preferable to use the thing which has a (meth) acryloyl group in a molecule | numerator from a liquid-crystal contamination property, for example, 2-methacryloyl oxyethyl isocyanate and 1- [4- (2-hydroxyethoxy The reaction product of) -phenyl] -2-hydroxy-2methyl-1-propan-1-one is preferably used. This compound can be prepared by the method described in WO 2006/027982. When content which occupies in the liquid crystal sealing agent of a photoinitiator makes the total amount of liquid crystal sealing agent 100 mass parts, about 1-10 mass parts is preferable.

The liquid crystal sealing agent of the present invention may further contain a curing accelerator such as an organic acid or imidazole, an organic filler, and an additive such as a pigment, a leveling agent, an antifoaming agent, or a solvent, if necessary.

As an example of the method of obtaining the liquid crystal sealing agent of this invention, there exists a method shown next. First, (d) component is melt-dissolved as needed for (c) component. Subsequently, component (b) is dissolved in this mixture, and component (h) is further dissolved as necessary. Subsequently, (a) component, (f) component, (e) component, (g) component, and an organic filler, an antifoamer, a leveling agent, a solvent, etc. are added as needed, and a well-known mixing apparatus, for example, 3 rolls The liquid crystal sealing agent of this invention can be manufactured by mixing uniformly with a sand mill, a ball mill, etc., and filtering by a metal mesh.

The liquid crystal display cell of this invention arrange | positions a pair of board | substrates which provided the predetermined electrode in the board | substrate at predetermined intervals, seals the circumference with the liquid crystal sealing agent of this invention, and liquid crystal is enclosed in the clearance gap. The type of the liquid crystal to be enclosed is not particularly limited. Here, a board | substrate is comprised with the combination board | substrate which has light transmittance in at least one which consists of glass, quartz, a plastic, silicon, etc. As the manufacturing method, after adding a spacer (gap control material), such as glass fiber, to the liquid crystal sealing agent of this invention, the liquid crystal sealing agent is apply | coated to one of the pair of board | substrates using a dispenser, a screen printing apparatus, etc. After that, temporary curing is performed at 80 to 120 ° C as necessary. Then, liquid crystal is dripped inside the bank of the liquid crystal sealing agent, another glass substrate is piled up in a vacuum, and a gap bet is performed. 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. When used as a photothermal additive type, ultraviolet rays are irradiated to the liquid crystal seal part by an ultraviolet ray irradiator to effect photo curing. The amount of ultraviolet irradiation is preferably 500 to 6000 mJ / cm 2, and more preferably 1000 to 4000 mJ / cm 2. Thereafter, if necessary, the liquid crystal display cell of the present invention can be obtained by curing at 90 to 130 ° C for 1 to 2 hours. The liquid crystal display cell of this invention obtained in this way does not have the display defect by liquid crystal contamination, and is excellent in adhesiveness and moisture resistance reliability. As a spacer, glass fiber, silica beads, polymer beads, etc. are mentioned, for example. Although the diameter differs according to the objective, it is 2-8 micrometers normally, Preferably it is 4-7 micrometers. The usage-amount is 0.1-4 mass parts normally with respect to 100 mass parts of liquid crystal sealing agents of this invention, Preferably it is 0.5-2 mass parts, More preferably, it is about 0.9-1.5 mass parts.

The liquid crystal sealing agent for liquid crystal dropping methods of this invention is very favorable in thermosetting, and it hardens | cures rapidly in the heating process in a liquid crystal dropping method. Therefore, the dissolution of the constituent components into the liquid crystal is very small, and it is possible to reduce the display defect of the liquid crystal display cell. Moreover, since it is excellent also in handling property and storage stability, it is suitable for manufacture of a liquid crystal display cell. Further, since the cured product is excellent in various cured properties such as adhesive strength, heat resistance and moisture resistance, it is possible to manufacture a liquid crystal display cell having excellent reliability by using the liquid crystal sealing agent of the present invention. Moreover, the liquid crystal display cell manufactured using the liquid crystal sealing agent of this invention also satisfy | fills the characteristic required as a liquid crystal display cell with high voltage retention and low ion density.

Example

Hereinafter, the present invention will be described in more detail with reference to Synthesis Examples and Examples, but the present invention is not limited to Examples. In addition, "part" and "%" are mass references | standards in a text unless there is particular notice.

[Synthesis Example 1]

(Synthesis of 1-hydroxy-2-trimethylsiloxy-1,1,2,2-tetraphenylethane)

100 parts (0.28 mol) of commercial benzopinacol (made by Tokyo Chemical) was dissolved in 350 parts of dimethylformaldehyde, and 32 parts (0.4 mol) of pyridine as a base catalyst and 150 parts of BSTFA (produced by Shin-Etsu Chemical Co., Ltd.) as a silylating agent were added thereto. (0.58 mol) was added and it heated up to 70 degreeC and stirred for 2 hours. The obtained reaction liquid was cooled, 200 parts of water was added while stirring, the product was precipitated, and the unreacted silylating agent was deactivated. After filtration and washing, the mixture was washed with water sufficiently, recrystallized with acetone, and purified to obtain 105.6 parts (yield 88.3%) of 1-hydroxy-2-trimethylsiloxy-1,1,2,2-tetraphenylethane. As a result of analysis by HPLC, it was 99.0% (area percentage). Moreover, the molecular ion peak of 438 was obtained by HPLC-MASS. DMSO-d ₆ It identified as the target object from the NMR (proton) spectrum which melt | dissolved in the. As chemical shift values of the NMR spectrum, hydroxyl group protons 5.8 ppm (1H), siloxymethylproton 0.0 ppm (9H), phenylproton 7.1 ppm (16H), 7.4 ppm (4H) were obtained.

[Referential Synthesis Example 1]

(Synthesis of epoxy acrylate of bisphenol A type epoxy resin)

282.5 g of bisphenol A type epoxy resin (product name: YD-8125, manufactured by Shinnitetsu Chemical Co., Ltd.) was dissolved in 266.8 g of toluene, 0.8 g of dibutylhydroxytoluene was added thereto, and the temperature was raised to 60 ° C. Then, 117.5 g of 100% equivalent of acrylic acid of an epoxy group was added, it heated up to 80 degreeC again, 0.6 g of trimethylammonium chloride which is a reaction catalyst was added to this, and it stirred at 98 degreeC for about 30 hours, and obtained the reaction liquid. . The reaction solution was washed with water and toluene was distilled off to obtain 395 g of the desired bisphenol A type epoxy acrylate (KAYARAD ^RTM R-93100).

[Examples 1-5, Comparative Examples 1-3]

(Preparation of liquid crystal sealant for liquid crystal dropping process)

After mixing and stirring each resin component (component (c) and component (d)) in the ratio shown in following Table 1, the radical polymerization inhibitor (component (b)) and the photoinitiator (component (h)) were heat-dissolved. . After cooling to room temperature, a silane coupling agent (component (f)), an inorganic filler (component (g)), a thermal radical initiator (component (a)), a thermosetting agent (component (e)), and the like are appropriately added and stirred. Then, after disperse | distributing with three roll mills, it filtered by the metal mesh (635 mesh) and prepared the liquid crystal sealing agent for liquid crystal dropping methods of Examples 1-5. Similarly, the liquid crystal sealing compound for liquid crystal dropping methods of Comparative Examples 1-3 was prepared using each component shown in Table 1.

Evaluation item contents and the result of the sealing compound for liquid crystal dropping methods prepared below are shown.

(Thermosetting test)

The prepared liquid crystal sealing compound for liquid crystal dropping methods was shape | molded at 3 cm x 3 cm x 1 mm, and it hardened at 120 degreeC x 1 hr. Curability was evaluated by measuring the Shore A hardness of hardened | cured material. The results are shown in Table 1.

(Handling test)

After mixing 0.15g of 5 micrometers spacers (PF-50S: Nippon Electric Glass Co., Ltd. product) with 15 g of liquid crystal sealing agents for each liquid crystal dropping method prepared, vacuum stirring and defoaming was carried out at 500 rpm and 1500 rpm of rotation for 5 minutes. As a vacuum stirring defoaming apparatus, the vacuum stirring defoaming mixer VMXC-360K: EME Corporation make was used. It placed in 23 degreeC atmosphere, the time to gelate was measured, and the following references | standards evaluated. The results are shown in Table 1.

○: It does not gel over 168 hours

(Triangle | delta): It gelled in 96 hours or more and less than 168 hours.

X: Gelled in less than 96 hours immediately after defoaming

(Liquid crystal contamination test)

After apply | coating about 100 mg of liquid crystal sealing agents for each liquid crystal dropping methods after irradiating 3000 mJ / cm <2> ultraviolet-rays to the bottom of a 10 ml vial bottle, 10 times the liquid crystal (MLC-6866-100: Merck Corporation make) was added. . After heating at 120 degreeC for 1 hour, it cooled for 30 minutes. Each supernatant was aliquoted by decantation, and the resistivity value was measured with the digital ultrahigh-resistance meter (R8340: Advantest Co., Ltd. product), and it compared with the resistivity value of the thing without a sealing compound. The determination was made based on the following criteria.

○: Specific resistance value 1.0 E + 11 or more

Δ ： Specific resistance value 1.0 E + 11 or more Less than 1.0 E + 11

× ： Less than 1.0 E + 10 resistivity

In addition, "1.0E + 11" of a specific resistance value represents "1.0 * 10 <^11>", and other description is also the same.

In the results of Table 1, (a) a thermal radical polymerization initiator having no oxygen-oxygen bond (-OO-) and nitrogen-nitrogen bond (-N = N-) in the molecule, (b) a radical polymerization inhibitor, and (c ) It was confirmed that the liquid crystal sealing agent (Examples 1-5) for liquid crystal dropping methods containing curable resin which has a (meth) acryloyl group was very excellent in thermosetting, handling property, and liquid-crystal contamination. Especially, it was confirmed that especially the liquid crystal sealing agent (Examples 1-4) for liquid crystal dropping methods containing specific things, such as a naphthoquinone, as a radical polymerization inhibitor.

Industrial availability

The liquid crystal sealing agent for liquid crystal dropping methods of this invention has favorable curability by heat, and is also excellent in hardened | cured material characteristics, such as handling property, storage stability, and adhesive strength. Therefore, the degree of freedom of design of the liquid crystal display cell is ensured and the product contributes to productivity and long-term reliability thereof.

Claims

The method according to claim 1,
Liquid crystal sealing agent for liquid crystal dropping methods whose said component (a) is a compound represented by following formula (1).
[Chemical Formula 1]

3. The method according to claim 1 or 2,
Liquid crystal sealing agent for dripping methods whose said component (b) is 1 or 2 or more radical polymerization inhibitor chosen from following formula (2)-(4).
(2)

[In formula (2), R ⁷ Represents a hydrogen atom, a hydroxyl group, a linear or branched alkoxy group having 1 to 4 carbon atoms, or a linear or branched alkyl group having 1 to 4 carbon atoms.]
(3)

[In formula (3), R ⁸ Represents a hydrogen atom, a hydroxyl group, a linear or branched alkoxy group having 1 to 4 carbon atoms, a phenoxy group, acetamide group, amino group, carboxyl group, cyano group, benzoyloxy group, isothiocyanate group, or oxo group, and R ⁹ to R ¹² Each independently represents a linear or branched alkyl group having 1 to 4 carbon atoms.]
[Chemical Formula 4]

4. The method according to any one of claims 1 to 3,
Furthermore, the liquid crystal sealing agent for liquid crystal dropping methods containing (d) curable resin which has an epoxy group, and (e) thermosetting agent.

5. The method of claim 4,
Liquid crystal sealing agent for liquid crystal dropping methods whose said component (e) is organic acid hydrazide.

6. The method according to any one of claims 1 to 5,
Furthermore, (f) liquid crystal sealing agent for liquid crystal dropping methods containing a silane coupling agent.

7. The method according to any one of claims 1 to 6,
Furthermore, (g) liquid crystal sealing agent for liquid crystal dropping methods containing an inorganic filler.

The method according to any one of claims 1 to 7,
Furthermore, (h) liquid crystal sealing agent for liquid crystal dropping methods containing a photoinitiator.

The method according to claim 4 or 5,
The liquid crystal sealing compound for liquid crystal dropping methods whose content of the said component (b) is 0.0001-1 mass part, when the total amount of the said component (c) and the said component (d) is 100 mass parts.

10. The method according to any one of claims 1 to 9,
The manufacturing method of the liquid crystal sealing compound for liquid crystal dropping methods containing the process of melt | dissolving the said component (b) with respect to the said component (c).

The method according to claim 4 or 5,
The manufacturing method of the liquid crystal sealing compound for liquid crystal dropping methods containing the process of melt | dissolving the said component (b) with respect to the said component (d).

In the hardened | cured material obtained by hardening | curing the liquid crystal sealing agent for liquid crystal dropping methods of any one of Claims 1-9, or the liquid crystal sealing agent for liquid crystal dropping methods obtained by the manufacturing method of Claim 10 or 11. Sealed liquid crystal display cell.