WO2019221027A1

WO2019221027A1 - Liquid crystal display element sealing agent, vertical conduction material, and liquid crystal display element

Info

Publication number: WO2019221027A1
Application number: PCT/JP2019/018764
Authority: WO
Inventors: 慶枝松井
Original assignee: 積水化学工業株式会社
Priority date: 2018-05-17
Filing date: 2019-05-10
Publication date: 2019-11-21
Also published as: TW201947000A; TWI813685B; JP6773907B2; JPWO2019221027A1

Abstract

An objective of the present invention is to provide a liquid crystal display element sealing agent such that penetration of the sealing agent by liquid crystal and pollution of the liquid crystal by the sealing agent can be suppressed, the sealing agent has excellent adhesiveness, and a liquid crystal display element having excellent display performance can be obtained. Another objective of the present invention is to provide a vertical conduction material and a liquid crystal display element formed using the liquid crystal display element sealing agent. The present invention provides a liquid crystal display element sealing agent containing a curable resin, a heat-curing agent, and soft particles having a maximum particle diameter of no less than 100% of the cell gaps in the liquid crystal display element, the curable resin being a compound having three or more epoxy groups within one molecule.

Description

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

The present invention relates to a sealing agent for a liquid crystal display element, which can suppress liquid crystal contamination due to insertion into a sealing agent by liquid crystal and liquid crystal contamination by the sealing agent, and can obtain a liquid crystal display element having excellent adhesiveness and excellent display performance. Moreover, this invention relates to the vertical conduction material and liquid crystal display element which use this sealing compound for liquid crystal display elements.

In recent years, as a method for manufacturing a liquid crystal display element such as a liquid crystal display cell, dripping using a sealing agent as disclosed in Patent Document 1 and Patent Document 2 from the viewpoint of shortening tact time and optimizing the amount of liquid crystal used. A liquid crystal dropping method called a construction method is used.
In the dropping method, first, a sealing agent is applied to one of the two transparent substrates with electrodes to form a frame-shaped seal pattern. Next, liquid crystal microdrops are dropped on the entire surface of the seal pattern frame with the sealant uncured, and the other transparent substrate is immediately bonded together, and the seal portion is irradiated with light such as ultraviolet rays or heated. Thus, the sealing agent is cured to produce a liquid crystal display element. If the substrates are bonded together under reduced pressure, a liquid crystal display element can be manufactured with extremely high efficiency, and this dripping method is currently the mainstream method for manufacturing liquid crystal display elements.

By the way, in the present age when mobile devices with various liquid crystal panels such as mobile phones and portable game machines are widespread, downsizing of devices is the most demanded issue. As a technique for miniaturization, there is a narrow frame of the liquid crystal display unit, and for example, the position of the seal portion is arranged under the black matrix (hereinafter also referred to as “narrow frame design”).
However, when a liquid crystal display element with a narrow frame design is manufactured by the dropping method, the sealing agent is arranged directly under the black matrix. Therefore, when the sealing agent is cured by light irradiation, the irradiated light is blocked and the inside of the sealing agent is blocked. It is difficult for light to reach the surface, and the curing of the sealant may be insufficient. As described above, when the sealant is insufficiently cured, there is a problem in that the uncured sealant component is eluted in the liquid crystal and easily causes liquid crystal contamination.

Therefore, it has been studied to cure the sealant only by heat, but without curing by light irradiation, the liquid crystal flows when heated and inserted into the sealant part during curing, resulting in tearing of the seal pattern, etc. Or the liquid crystal is contaminated by a sealant whose viscosity is reduced by heating.
In particular, in recent years, the line width of the sealant to be applied has become narrower and the cross-sectional area of the seal after bonding has become smaller as the panel becomes narrower. Therefore, the seal pattern is easily broken.

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

The present invention provides a sealant for a liquid crystal display element that can suppress liquid crystal contamination due to insertion into a sealant with liquid crystal and liquid crystal contamination due to the sealant, and that can provide a liquid crystal display element with excellent adhesiveness and excellent display performance. With the goal. Another object of the present invention is to provide a vertical conduction material and a liquid crystal display element using the sealing agent for a liquid crystal display element.

The present invention contains a curable resin, a thermosetting agent, and flexible particles having a maximum particle size of 100% or more of the cell gap of the liquid crystal display element, and the curable resin is 3 or more per molecule. It is the sealing compound for liquid crystal display elements containing the compound which has the epoxy group of.
The present invention is described in detail below.

In recent years, PSA (Polymer Stained Alignment) type liquid crystal display elements have attracted attention as liquid crystal display elements that can realize high-speed response and high contrast. In the PSA type liquid crystal display element, a liquid crystal composition containing a polymerizable compound is used, and the liquid crystal composition in the liquid crystal composition is irradiated by irradiating light to the liquid crystal composition filled in the cell of the liquid crystal display element. The compound is polymerized to form a concavo-convex shape on the substrate, thereby giving a uniform pretilt angle and controlling the alignment of liquid crystal molecules. However, when a PSA type liquid crystal display element is sealed using a conventional sealant, there is a problem that uneven shapes formed on the substrate vary, and a uniform pretilt angle may not be provided. .

The present inventor has found that when a PSA type liquid crystal display element is sealed using a conventional sealant, the unevenness formed on the substrate may cause variations in the sealant as a curable resin. It was considered to be in the (meth) acrylic compound contained. That is, when the polymerizable compound in the liquid crystal is polymerized by elution of the (meth) acrylic compound in the curable resin, the (meth) acrylic compound is also polymerized, and the (meth) acrylic compound is polymerized. It was considered that the uneven shape different from the intended one was formed in the part. In view of this, the present inventor has studied sealing a PSA type liquid crystal display element using a sealing agent that does not contain a (meth) acrylic compound or has a reduced content of a (meth) acrylic compound. When using an appropriate sealing agent, there is a problem that the liquid crystal is likely to be inserted into the sealing agent. Therefore, the present inventor has studied to suppress insertion of liquid crystal into the sealing agent and liquid crystal contamination due to the sealing agent by blending flexible particles whose maximum particle diameter is 100% or more of the cell gap of the liquid crystal display element. . However, if a large amount of flexible particles is blended in order to sufficiently suppress liquid crystal contamination due to insertion into the sealant or liquid crystal due to the sealant, there is a problem that the resulting sealant is inferior in adhesiveness. Therefore, the present inventor further examined the use of a compound having three or more epoxy groups in one molecule as the curable resin. As a result, it is possible to obtain a sealant for a liquid crystal display element that can suppress liquid crystal contamination due to insertion into the sealant with liquid crystal and liquid crystal contamination due to the sealant, and can obtain a liquid crystal display element having excellent adhesion and excellent display performance. As a result, the present invention has been completed.
The effect of suppressing the insertion of the liquid crystal into the sealing agent and the liquid crystal contamination by the sealing agent in the sealing agent for a liquid crystal display element of the present invention is particularly remarkable when the sealing agent is cured only by heat. Moreover, the sealing compound for liquid crystal display elements of this invention is used suitably as a sealing compound for PSA type liquid crystal display elements.

The sealing agent for liquid crystal display elements of this invention contains curable resin.
The curable resin contains a compound having three or more epoxy groups in one molecule (hereinafter also referred to as “trifunctional or higher functional epoxy compound”). When the sealing agent for liquid crystal display elements of the present invention contains the above trifunctional or higher epoxy compound, insertion of liquid crystal into the sealing agent can be suppressed, and the obtained liquid crystal display element has excellent display performance. It becomes.

The trifunctional or higher functional epoxy compound is excellent in reactivity, and the obtained sealing agent for liquid crystal display elements is excellent in the effect of suppressing the liquid crystal contamination due to the insertion into the sealing agent by the liquid crystal and the sealing agent. It preferably has 6 or more epoxy groups.
In addition, since the above-described trifunctional or higher functional epoxy compound is excellent in the effect of suppressing the insertion of liquid crystal into the sealant, a compound having three or more epoxy groups and an isocyanuric skeleton in one molecule, and / or 1 It is preferably a glycidylamine type epoxy compound having three or more epoxy groups in the molecule. More preferably, it is a compound having three or more epoxy groups and an isocyanuric skeleton in one molecule.

Specific examples of the trifunctional or higher functional epoxy compound include a compound represented by the following formula (1), a compound represented by the following formula (2), a compound represented by the following formula (3), and the like. Can be mentioned. Especially, the compound represented by the following formula (1) and the compound represented by the following formula (2) are preferable, and the compound represented by the following formula (1) is more preferable.

The curable resin may contain another curable resin in addition to the trifunctional or higher functional epoxy compound. When the other curable resin is contained, the preferable lower limit of the content of the trifunctional or higher functional epoxy compound in 100 parts by weight of the curable resin is 50 parts by weight, and the preferable upper limit is 95 parts by weight. When the content of the above-mentioned trifunctional or higher functional epoxy compound is within this range, the resulting liquid crystal display element sealant is excellent in the effect of suppressing elution into the liquid crystal and the insertion of the liquid crystal into the sealant. . The more preferable lower limit of the content of the trifunctional or higher epoxy compound is 60 parts by weight, and the more preferable upper limit is 90 parts by weight.

As said other curable resin, a monofunctional epoxy compound or a bifunctional epoxy compound is used suitably.

As said monofunctional epoxy compound or said bifunctional epoxy compound, the part which has one or two epoxy groups in 1 molecule formed by making a part of epoxy group of a polyfunctional epoxy compound react with (meth) acrylic acid A (meth) acryl-modified epoxy resin (hereinafter also simply referred to as “partial (meth) acryl-modified epoxy resin”) is preferable. In particular, since the fast curing property of the obtained sealant for liquid crystal display elements is improved and the effect of suppressing the insertion of the liquid crystal into the sealant is excellent, the above-mentioned partial (meth) acryl-modified epoxy resin is heat described later. It is preferable to use in combination with a radical polymerization initiator.

Examples of other monofunctional epoxy compounds include allyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, p-tert-butylphenyl glycidyl ether, and glycidyl (meth) acrylate.
In the present specification, the “(meth) acryl” means acryl or methacryl, and the “(meth) acrylate” means acrylate or methacrylate.

Examples of other bifunctional epoxy compounds include bisphenol A type bifunctional epoxy compounds, bisphenol F type bifunctional epoxy compounds, bisphenol S type bifunctional epoxy compounds, and 2,2′-diallyl bisphenol A type bifunctional. Epoxy compounds, hydrogenated bisphenol type bifunctional epoxy compounds, propylene oxide added bisphenol A type bifunctional epoxy compounds, resorcinol type bifunctional epoxy compounds, biphenyl type bifunctional epoxy compounds, sulfide type bifunctional epoxy compounds, diphenyl ether type bifunctional epoxy compounds , Dicyclopentadiene type bifunctional epoxy compound, naphthalene type bifunctional epoxy compound, glycidylamine type bifunctional epoxy compound, alkyl polyol type bifunctional epoxy compound, rubber modified bifunctional type Epoxy compounds, bifunctional glycidyl ester compounds and the like.

The sealing agent for a liquid crystal display element of the present invention may contain a (meth) acrylic compound having no epoxy group as the other curable resin, but by elution into the liquid crystal in the case of a PSA type liquid crystal display element. From the viewpoint of suppressing adverse effects on the uneven shape, it is preferable not to contain a (meth) acrylic compound having no epoxy group.
In the present specification, the “(meth) acrylic compound” means a compound having a (meth) acryloyl group, and the “(meth) acryloyl” means acryloyl or methacryloyl.

The sealing agent for liquid crystal display elements of this invention contains a thermosetting agent.
Examples of the thermosetting agent include organic acid hydrazides, imidazole derivatives, amine compounds, polyhydric phenol compounds, acid anhydrides, and the like. Of these, organic acid hydrazide is preferably used.
The said thermosetting agent may be used independently and 2 or more types may be used in combination.

Examples of the organic acid hydrazide include sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, malonic acid dihydrazide, and the like.
Examples of commercially available organic acid hydrazides include organic acid hydrazides manufactured by Otsuka Chemical Co., Ltd., organic acid hydrazides manufactured by Ajinomoto Fine Techno Co., and organic acid hydrazides manufactured by Nippon Finechem Co., Ltd., and the like.
Examples of the organic acid hydrazide manufactured by Otsuka Chemical Co., Ltd. include SDH and ADH.
Examples of the organic acid hydrazide manufactured by Ajinomoto Fine Techno Co. include Amicure VDH, Amicure VDH-J, Amicure UDH, Amicure UDH-J, and the like.
Examples of the organic acid hydrazide manufactured by Nippon Finechem Co., Ltd. include MDH.

The content of the thermosetting agent is preferably 1 part by weight with respect to 100 parts by weight of the curable resin, and 50 parts by weight with respect to the preferable upper limit. When the content of the thermosetting agent is within this range, the thermosetting property can be improved without deteriorating the applicability of the obtained sealing agent for liquid crystal display elements. The upper limit with more preferable content of the said thermosetting agent is 30 weight part.

It is preferable that the sealing agent for liquid crystal display elements of this invention contains a polymerization initiator.
Examples of the polymerization initiator include radical polymerization initiators and cationic polymerization initiators.
Especially, it is preferable to contain a radical polymerization initiator as said polymerization initiator. The spring back by the soft particles described later is affected not only by the maximum particle size of the soft particles but also by the curing rate of the sealant. Since the radical polymerization initiator can significantly increase the curing rate compared to the thermosetting agent, by using in combination with the flexible particles, it suppresses the occurrence of springback that is likely to occur due to the flexible particles, The obtained liquid crystal display element becomes more excellent in gap retention.

Examples of the radical polymerization initiator include a thermal radical polymerization initiator that generates radicals by heating, a photo radical polymerization initiator that generates radicals by light irradiation, and the like. Among these, a thermal radical polymerization initiator is preferable. In particular, as described above, since the fast curing property of the obtained sealing agent for liquid crystal display elements is improved and the effect of suppressing insertion of the liquid crystal into the sealing agent is excellent, the partial (meth) acryl-modified epoxy is used. More preferably, the resin is used in combination with the thermal radical polymerization initiator.

As said thermal radical polymerization initiator, what is comprised with an azo compound, an organic peroxide, etc. is mentioned, for example. Among them, from the viewpoint of suppressing liquid crystal contamination, an initiator composed of an azo compound (hereinafter also referred to as “azo initiator”) is preferable, and an initiator composed of a polymer azo compound (hereinafter referred to as “polymer azo”). (Also referred to as “initiator”) is more preferred.
The said thermal radical polymerization initiator may be used independently, and 2 or more types may be used in combination.
In the present specification, the “polymer azo compound” means a compound having an azo group and generating a radical capable of reacting with a (meth) acryloyl group by heat and having a number average molecular weight of 300 or more. To do.

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

Examples of the polymer azo compound include those having a structure in which a plurality of units such as polyalkylene oxide and polydimethylsiloxane are bonded via an azo group.
As the polymer azo compound having a structure in which a plurality of units such as polyalkylene oxide are bonded via the azo group, those having a polyethylene oxide structure are preferable.
Specific examples of the polymer azo compound include polycondensates of 4,4′-azobis (4-cyanopentanoic acid) and polyalkylene glycol, and 4,4′-azobis (4-cyanopentanoic acid). And a polycondensate of polydimethylsiloxane having a terminal amino group.
Examples of commercially available polymer azo initiators include VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS-1001 (all manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.). Can be mentioned.
Examples of the azo initiator that is not a polymer include V-65 and V-501 (both manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.).

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

The said thermal radical polymerization initiator may be used independently, and 2 or more types may be used in combination.

Examples of the photo radical polymerization initiator include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, and thioxanthone compounds.
Specific examples of the photo radical polymerization initiator include 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1-butanone, and 2- (dimethylamino). ) -2-((4-Methylphenyl) methyl) -1- (4- (4-morpholinyl) phenyl) -1-butanone, 2,2-dimethoxy-1,2-diphenylethane-1-one, bis ( 2,4,6-trimethylbenzoyl) phenylphosphine oxide, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 1- (4- (2-hydroxyethoxy) -phenyl) -2-Hydroxy-2-methyl-1-propan-1-one, 1- (4- (phenylthio) phenyl) -1,2-octanedione 2 (O-benzoyl oxime), 2,4,6-trimethylbenzoyl diphenylphosphine oxide, and the like.
The said radical photopolymerization initiator may be used independently and 2 or more types may be used in combination.

As the cationic polymerization initiator, a photocationic polymerization initiator is preferably used.
The cationic photopolymerization initiator is not particularly limited as long as it generates a protonic acid or a Lewis acid by light irradiation, and may be of an ionic photoacid generation type or a nonionic photoacid generation type. It may be.
Examples of the photocationic polymerization initiator include onium salts such as aromatic diazonium salts, aromatic halonium salts, and aromatic sulfonium salts, organometallic complexes such as iron-allene complexes, titanocene complexes, and arylsilanol-aluminum complexes. Is mentioned.

Examples of commercially available photocationic polymerization initiators include Adekaoptomer SP-150 and Adekaoptomer SP-170 (both manufactured by ADEKA).

The said cationic photopolymerization initiator may be used independently and 2 or more types may be used in combination.

The content of the polymerization initiator is preferably 0.01 parts by weight and preferably 10 parts by weight with respect to 100 parts by weight of the curable resin. When the content of the polymerization initiator is within this range, the obtained sealing agent for liquid crystal display elements is excellent in storage stability and curability while suppressing liquid crystal contamination. The minimum with more preferable content of the said polymerization initiator is 0.1 weight part, and a more preferable upper limit is 5 weight part.

The sealing agent for liquid crystal display elements of this invention is used suitably for sealing of the liquid crystal between the board | substrates of a PSA type liquid crystal display element.
The sealing agent for liquid crystal display elements of the present invention contains flexible particles (hereinafter also simply referred to as “soft particles”) having a maximum particle size of 100% or more of the cell gap of the liquid crystal display element. When the liquid crystal display device is manufactured, the flexible particles serve as a barrier between the other sealing agent component and the liquid crystal, preventing the liquid crystal from being inserted into the sealing agent and the sealing agent from being eluted into the liquid crystal. Have a role to play. Further, by blending the flexible particles, it is possible to prevent the substrate from being displaced until the sealing agent is cured after the substrates are bonded together.
The cell gap of the liquid crystal display element is not limited because it varies depending on the display element, but the cell gap of a general liquid crystal display element is 2 μm or more and 10 μm or less.

The maximum particle diameter of the flexible particles is 100% or more of the cell gap of the liquid crystal display element. When the maximum particle diameter of the flexible particles is 100% or more of the cell gap of the liquid crystal display element, the liquid crystal can be prevented from being inserted into the sealing agent and liquid crystal contamination due to the sealing agent. The maximum particle diameter of the flexible particles is preferably more than 100% of the cell gap of the liquid crystal display element. The maximum particle size of the flexible particles is preferably 5 μm or more.
The preferable upper limit of the maximum particle size of the flexible particles is 20 μm. When the maximum particle size of the flexible particles is 20 μm or less, the spring back is suppressed, and the obtained liquid crystal display element is more excellent in gap retention. A more preferable upper limit of the maximum particle size of the flexible particles is 15 μm.
Furthermore, the maximum particle size of the flexible particles is preferably 260% or less of the cell gap. When the maximum particle size of the flexible particles is 260% or less of the cell gap, the spring back is suppressed, and the obtained liquid crystal display device is more excellent in gap retention. A more preferred upper limit of the maximum particle size of the flexible particles is 220% of the cell gap, and a more preferred upper limit is 170% of the cell gap.
In the present specification, the maximum particle diameter of the flexible particles and the average particle diameter described later are values obtained by measuring the particles before blending with the sealant using a laser diffraction particle size distribution measuring device. Means. As the laser diffraction particle size distribution measuring device, Mastersizer 2000 (manufactured by Malvern) or the like can be used. Moreover, about the particle | grains contained in a sealing agent, the maximum value and the average value of the particle diameter of ten particles observed by the magnification of 10,000 times using the scanning electron microscope are meant. As the scanning electron microscope, a field emission scanning electron microscope S-4800 (manufactured by Hitachi High-Technologies Corporation) or the like can be used.
Further, in the liquid crystal display element, if the presence of flexible particles whose shape is distorted by being crushed by a bonded substrate in the cured cured sealant is confirmed, the maximum particle size of the flexible particles Is 100% or more of the cell gap of the liquid crystal display element.

In the flexible particles, the content ratio of particles having a particle diameter of 5 μm or more in the particle size distribution of the flexible particles measured by the laser diffraction type distribution measuring device is preferably 60% or more by volume frequency. When the content ratio of the particles having a particle diameter of 5 μm or more is 60% or more by volume frequency, the effect of suppressing insertion of liquid crystal into the sealing agent and liquid crystal contamination by the sealing agent is excellent. The content ratio of particles having a particle diameter of 5 μm or more is more preferably 80% or more.

In the flexible particle size distribution measured by the laser diffraction type distribution measuring device, the content ratio of particles of 100% or more of the cell gap of the liquid crystal display element is 70% or more by volume frequency. preferable. When the content ratio of particles of 100% or more of the cell gap of the liquid crystal display element is 70% or more by volume frequency, the liquid crystal display element is more excellent in the effect of suppressing insertion into the sealing agent by liquid crystal and liquid crystal contamination by the sealing agent. More preferably, the flexible particles are composed of particles having a volume content of 100% or more of the cell gap of the liquid crystal display element by volume frequency, ie, 100% or more of the cell gap of the liquid crystal display element. .

The preferable lower limit of the average particle diameter of the flexible particles is 2 μm, and the preferable upper limit is 15 μm. When the average particle diameter of the flexible particles is 2 μm or more, the effect of suppressing the liquid crystal contamination due to the insertion of the liquid crystal into the sealing agent and the sealing agent becomes excellent. When the average particle diameter of the flexible particles is 15 μm or less, the obtained liquid crystal display element is more excellent in gap retention. The more preferable lower limit of the average particle diameter of the flexible particles is 4 μm, and the more preferable upper limit is 12 μm.

As the flexible particles, two or more kinds of flexible particles having different maximum particle diameters may be mixed and used as long as the overall maximum particle diameter is in the above-described range. That is, a soft particle having a maximum particle diameter of less than 100% of the cell gap of the liquid crystal display element and a soft particle having a maximum particle diameter of 100% or more of the cell gap of the liquid crystal display element may be mixed and used.

The coefficient of variation (hereinafter also referred to as “CV value”) of the flexible particles is preferably 30% or less. When the CV value of the particle diameter of the flexible particles is 30% or less, the obtained liquid crystal display element is more excellent in gap retention. The CV value of the particle diameter of the flexible particles is more preferably 28% or less, and further preferably 15% or less.
In the present specification, the “CV value of particle diameter” means a value obtained by the following formula.
CV value of particle diameter (%) = (standard deviation of particle diameter / average particle diameter) × 100

Even if the maximum particle diameter, average particle diameter, and CV value are outside the above-mentioned ranges, the flexible particles are classified so that the maximum particle diameter, average particle diameter, and CV value are within the above-described ranges. Can do. In addition, flexible particles with a particle size of less than 100% of the cell gap of the liquid crystal display element do not contribute to the suppression of liquid crystal contamination due to the insertion of the liquid crystal into the sealing agent or the sealing agent. Therefore, it is preferable to remove by classification.
Examples of the method for classifying the flexible particles include wet classification and dry classification. Of these, wet classification is preferable, and wet sieving classification is more preferable.

The soft particles are unloaded from the reversal load value to the origin load value when releasing the load, with the compression displacement from the origin load value when applying the load to the predetermined reversal load value being L1. When the displacement is L2, it is preferable that the recovery rate expressed as a percentage of L2 / L1 is 80% or less. When the recovery rate of the flexible particles is 80% or less, the effect of suppressing insertion of liquid crystal into the sealant and liquid crystal contamination due to the sealant is excellent. A more preferable upper limit of the recovery rate of the flexible particles is 70%, and a more preferable upper limit is 60%.
Further, the recovery rate of the flexible particles is substantially 5% or more.
In addition, the recovery rate of the said soft particle | grain can be derived | led-out by applying a fixed load (1g) to one particle | grain using a micro compression tester, and analyzing the recovery behavior after removing the load.

The flexible particles preferably have a 1 g strain expressed as a percentage of L3 / Dn as a percentage of 30% or more when the compression displacement when a load of 1 g is applied is L3 and the particle diameter is Dn. When the 1 g strain of the flexible particles is 30% or more, the effect of suppressing insertion of liquid crystal into the sealing agent and liquid crystal contamination due to the sealing agent is improved. A more preferable lower limit of 1 g strain of the flexible particles is 40%.
The 1 g strain of the flexible particles can be derived by applying a load of 1 g to each particle using a micro compression tester and measuring the amount of displacement at that time.

The flexible particles preferably have a fracture strain expressed as a percentage of L4 / Dn of 50% or more, where L4 is the compression displacement when the particles are broken and Dn is the particle diameter. When the fracture strain of the flexible particles is 50% or more, the effect of suppressing the liquid crystal contamination due to the insertion into the sealing agent by the liquid crystal and the sealing agent becomes excellent. A more preferable lower limit of the fracture strain of the flexible particles is 60%.
The fracture strain of the flexible particle can be derived by applying a load to one particle using a micro compression tester and measuring the displacement at which the particle breaks. The compression displacement L4 is calculated as the time when the particle breaks when the amount of displacement increases discontinuously with respect to the applied load. If the deformation does not break even if the load is increased, the fracture strain is considered to be 100% or more.

The flexible particles have a preferable lower limit of the glass transition temperature of −200 ° C. and a preferable upper limit of 40 ° C. The lower the glass transition temperature of the flexible particles, the better the tendency from the viewpoint of preventing the liquid crystal from being inserted into the sealant and the liquid crystal contamination by the sealant. It will be better. When the glass transition temperature of the flexible particles is 40 ° C. or less, the obtained liquid crystal display element is more excellent in gap retention. A more preferable lower limit of the glass transition temperature of the flexible particles is −150 ° C., and a more preferable upper limit is 35 ° C.
In addition, the glass transition temperature of the said flexible particle shows the value measured by the differential scanning calorimetry (DSC) based on "The plastics transition temperature measuring method" of JISK7121.

Examples of the flexible particles include silicone particles, vinyl particles, urethane particles, fluorine particles, and nitrile particles. Of these, silicone particles and vinyl particles are preferable.

As said silicone type particle | grain, a silicone rubber particle is preferable from a dispersible viewpoint to resin.
Examples of commercially available silicone particles include KMP-594, KMP-597, KMP-598, KMP-600, KMP-601, KMP-602 (all manufactured by Shin-Etsu Chemical Co., Ltd.), Trefil E-506S, EP-9215 (both manufactured by Toray Dow Corning Co., Ltd.) and the like can be mentioned, and these can be classified and used. The said silicone type particle | grains may be used independently and 2 or more types may be used together.

(Meth) acrylic particles are preferably used as the vinyl particles.
The (meth) acrylic particles can be obtained by polymerizing monomers as raw materials by a known method. Specifically, for example, a method in which a monomer is suspension-polymerized in the presence of a radical polymerization initiator, and a seed particle is swollen by absorbing the monomer into a non-crosslinked seed particle in the presence of a radical polymerization initiator. And a seed polymerization method.
In the present specification, the “(meth) acryl” means acryl or methacryl.

A monofunctional monomer can be used as a monomer as a raw material for forming the (meth) acrylic particles.
Examples of the monofunctional monomer include alkyl mono (meth) acrylates, oxygen atom-containing mono (meth) acrylates, nitrile-containing mono (meth) acrylic monomers, and fluorine atom-containing mono (meth) acrylates.
Examples of the alkyl mono (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2- Examples include ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, and isobornyl (meth) acrylate.
Examples of the oxygen atom-containing mono (meth) acrylate include 2-hydroxyethyl (meth) acrylate, glycerol (meth) acrylate, polyoxyethylene (meth) acrylate, and glycidyl (meth) acrylate.
Examples of the nitrile-containing mono (meth) acrylic monomer include (meth) acrylonitrile.
Examples of the fluorine atom-containing mono (meth) acrylate include trifluoromethyl (meth) acrylate and pentafluoroethyl (meth) acrylate.
Especially, since the glass transition temperature of a homopolymer is low and the deformation amount when a 1-g load is applied can be enlarged, alkyl mono (meth) acrylate is preferable.
In the present specification, the “(meth) acrylate” means acrylate or methacrylate.

Further, a polyfunctional monomer may be used as the monomer in order to give a crosslinked structure.
Examples of the polyfunctional monomer include tetramethylolmethane tetra (meth) acrylate, tetramethylolmethane tri (meth) acrylate, tetramethylolmethane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and dipentaerythritol. Hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, glycerol tri (meth) acrylate, glycerol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate , (Poly) tetramethylene di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, isocyanuric acid skeleton tri ( Data) acrylate, and the like. Especially, since the molecular weight between cross-linking points is large and the deformation amount when a 1 g load is applied can be increased, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, ( Poly) tetramethylene di (meth) acrylate, 1,4-butanediol di (meth) acrylate, and 1,6-hexanediol di (meth) acrylate are preferred.

A preferable lower limit of the amount of the polyfunctional monomer used in the whole monomer is 1% by weight, and a preferable upper limit is 90% by weight. When the amount of the polyfunctional monomer used is 1% by weight or more, the solvent resistance of the flexible particles is improved, and when mixed with other sealing agent components, problems such as swelling do not occur, and it is uniform. Easy to disperse. When the amount of the polyfunctional monomer used is 90% by weight or less, the recovery rate of the flexible particles can be lowered, and problems such as springback are less likely to occur. A more preferable lower limit of the amount of the polyfunctional monomer used is 3% by weight, and a more preferable upper limit is 80% by weight.

Furthermore, as the above monomer, in addition to these acrylic monomers, for example, styrene monomers, vinyl ethers, vinyl esters, unsaturated hydrocarbons, halogen atom-containing monomers And monomers such as triallyl (iso) cyanurate, triallyl trimellitate, divinylbenzene, diallyl phthalate, diallylacrylamide, diallyl ether, 3- (meth) acryloxypropyltrimethoxysilane, vinyltrimethoxysilane May be.
Examples of the styrene monomer include styrene, α-methylstyrene, trimethoxysilylstyrene, and the like.
Examples of the vinyl ethers include methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, and the like.
Examples of the vinyl esters include vinyl acetate, vinyl butyrate, vinyl laurate, and vinyl stearate.
Examples of the unsaturated hydrocarbon include ethylene, propylene, isoprene, butadiene and the like.
Examples of the halogen atom-containing monomer include vinyl chloride, vinyl fluoride, chlorostyrene, and the like.

Further, as the vinyl particles, for example, polydivinylbenzene particles, polychloroprene particles, butadiene rubber particles and the like may be used.

Examples of commercially available urethane-based particles include Art Pearl (manufactured by Negami Kogyo Co., Ltd.), Dimic Beads (manufactured by Dainichi Seika Kogyo Co., Ltd.), and the like, which can be classified and used. .

The preferable lower limit of the hardness of the flexible particles is 3, and the preferable upper limit is 50. When the hardness of the flexible particles is within this range, the obtained liquid crystal display element is more excellent in gap retention. The more preferable lower limit of the hardness of the flexible particle is 10, the more preferable upper limit is 40, and the more preferable lower limit is 20.
In the present specification, the above-mentioned “hardness of flexible particles” means durometer A hardness measured by a method based on JIS K 6253.

The minimum with preferable content of the said flexible particle in the sealing compound for liquid crystal display elements of this invention is 5 weight%, and a preferable upper limit is 60 weight%. When the content of the flexible particles is 5% by weight or more, the effect of suppressing insertion of liquid crystal into the sealing agent and liquid crystal contamination due to the sealing agent is improved. When the content of the flexible particles is 60% by weight or less, the obtained sealing agent for liquid crystal display elements is more excellent in adhesiveness. The more preferable lower limit of the content of the flexible particles is 10% by weight, the more preferable upper limit is 50% by weight, the still more preferable lower limit is 20% by weight, and the still more preferable upper limit is 40% by weight.

The sealing agent for liquid crystal display elements of the present invention preferably contains a filler for the purpose of improving the viscosity, improving the adhesiveness due to the stress dispersion effect, improving the linear expansion coefficient, and the like.

As the filler, an inorganic filler or an organic filler can be used.
Examples of the inorganic filler include silica, talc, glass beads, asbestos, gypsum, diatomaceous earth, smectite, bentonite, montmorillonite, sericite, activated clay, alumina, zinc oxide, iron oxide, magnesium oxide, tin oxide, and titanium oxide. , Calcium carbonate, magnesium carbonate, magnesium hydroxide, aluminum hydroxide, aluminum nitride, silicon nitride, barium sulfate, calcium silicate and the like.
Examples of the organic filler include polyester fine particles, polyurethane fine particles, vinyl polymer fine particles, and acrylic polymer fine particles.
The said filler may be used independently and 2 or more types may be used in combination.

The preferable lower limit of the content of the filler in 100 parts by weight of the sealant for liquid crystal display elements of the present invention is 10 parts by weight, and the preferable upper limit is 70 parts by weight. When the content of the filler is within this range, the effect of improving adhesiveness and the like is improved without deteriorating applicability and the like. The minimum with more preferable content of the said filler is 20 weight part, and a more preferable upper limit is 60 weight part.

The sealing agent for liquid crystal display elements of the present invention may contain a silane coupling agent. The silane coupling agent mainly has a role as an adhesion assistant for favorably bonding the sealing agent and the substrate.

As the silane coupling agent, for example, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-isocyanatopropyltrimethoxysilane and the like are preferably used. These are excellent in the effect of improving the adhesion to a substrate or the like, and can suppress the outflow of the curable resin into the liquid crystal by chemically bonding with the curable resin.
The said silane coupling agent may be used independently and 2 or more types may be used in combination.

The minimum with preferable content of the said silane coupling agent in 100 weight part of sealing compounds for liquid crystal display elements of this invention is 0.1 weight part, and a preferable upper limit is 10 weight part. When the content of the silane coupling agent is within this range, the effect of improving the adhesiveness is suppressed while suppressing liquid crystal contamination. The minimum with more preferable content of the said silane coupling agent is 0.3 weight part, and a more preferable upper limit is 5 weight part.

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

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

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

The above-mentioned titanium black exhibits a sufficient effect even if it is not surface-treated, but the surface is treated with an organic component such as a coupling agent, silicon oxide, titanium oxide, germanium oxide, aluminum oxide, oxidized Surface-treated titanium black such as those coated with an inorganic component such as zirconium or magnesium oxide can also be used. Especially, what is processed with the organic component is preferable at the point which can improve insulation more.
In addition, the liquid crystal display element produced using the sealing agent for liquid crystal display elements of the present invention containing the above-described titanium black as a light-shielding agent has sufficient light-shielding properties, and therefore has high contrast without light leakage. A liquid crystal display element having excellent image display quality can be realized.

Examples of commercially available titanium black include titanium black manufactured by Mitsubishi Materials Corporation and titanium black manufactured by Ako Kasei Co., Ltd.
Examples of the titanium black manufactured by Mitsubishi Materials include 12S, 13M, 13M-C, 13R-N, and 14M-C.
Examples of the titanium black manufactured by Ako Kasei Co., Ltd. include Tilac D.

The preferable lower limit of the specific surface area of the titanium black is 13 m ² / g, the preferable upper limit is 30 m ² / g, the more preferable lower limit is 15 m ² / g, and the more preferable upper limit is 25 m ² / g.
Further, the preferred lower limit of the volume resistance of the titanium black is 0.5 Ω · cm, the preferred upper limit is 3 Ω · cm, the more preferred lower limit is 1 Ω · cm, and the more preferred upper limit is 2.5 Ω · cm.

Although the primary particle diameter of the said light-shielding agent will not be specifically limited if it is below the distance between the board | substrates of a liquid crystal display element, a preferable minimum is 1 nm and a preferable upper limit is 5000 nm. When the primary particle diameter of the light-shielding agent is within this range, the light-shielding property can be improved without deteriorating the applicability of the obtained sealing agent for liquid crystal display elements. The more preferable lower limit of the primary particle diameter of the light shielding agent is 5 nm, the more preferable upper limit is 200 nm, the still more preferable lower limit is 10 nm, and the still more preferable upper limit is 100 nm.
The primary particle size of the light shielding agent can be measured by using NICOMP 380ZLS (manufactured by PARTICS SIZING SYSTEMS) and dispersing the light shielding agent in a solvent (water, organic solvent, etc.).

The preferable lower limit of the content of the light-shielding agent in 100 parts by weight of the sealant for liquid crystal display elements of the present invention is 5 parts by weight, and the preferable upper limit is 80 parts by weight. When the content of the light-shielding agent is within this range, a superior light-shielding property is exhibited without greatly reducing the adhesiveness, strength after curing, and drawing property of the obtained sealing agent for liquid crystal display elements. be able to. The more preferable lower limit of the content of the light shielding agent is 10 parts by weight, the more preferable upper limit is 70 parts by weight, the still more preferable lower limit is 30 parts by weight, and the still more preferable upper limit is 60 parts by weight.

The sealant for a liquid crystal display element of the present invention may further include a stress relaxation agent, a reactive diluent, a thixotropic agent, a spacer, a curing accelerator, an antifoaming agent, a leveling agent, a polymerization inhibitor, etc., if necessary. The additive may be contained.

The method for producing the sealing agent for liquid crystal display elements of the present invention is not particularly limited. For example, using a mixer, a curable resin, a thermosetting agent, flexible particles, and a silane coupling added as necessary. The method of mixing additives, such as an agent, is mentioned.
Examples of the mixer include a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, and a three roll.

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

As the conductive fine particles, a metal ball, a resin fine particle formed with a conductive metal layer on the surface, or the like can be used. Among them, the one in which the conductive metal layer is formed on the surface of the resin fine particles is preferable because the conductive connection is possible without damaging the transparent substrate due to the excellent elasticity of the resin fine particles.

The liquid crystal display element using the sealing agent for liquid crystal display elements of this invention or the vertical conduction material of this invention is also one of this invention.
As the liquid crystal display element of the present invention, a liquid crystal display element having a narrow frame design is preferable. Specifically, the width of the frame portion around the liquid crystal display unit is preferably 2 mm or less.
Moreover, it is preferable that the application | coating width | variety of the sealing compound for liquid crystal display elements of this invention at the time of manufacturing the liquid crystal display element of this invention is 1 mm or less.

As a method for producing the liquid crystal display element of the present invention, a liquid crystal dropping method is preferably used. Specific examples include a method having the following steps.
First, a process for forming a frame-shaped seal pattern by applying the liquid crystal display element sealant of the present invention to one of two transparent substrates having an electrode such as an ITO thin film and an alignment film by screen printing, dispenser application, etc. I do. Next, the liquid crystal composition-containing liquid crystal composition-containing liquid crystal composition-containing liquid crystal composition containing the polymerizable compound in an uncured sealant is dropped into the seal pattern frame of the substrate, and the other transparent substrate is applied under vacuum. The process of superimposing is performed. Then, the process of hardening the sealing compound for liquid crystal display elements of this invention by heating is performed. Furthermore, a PSA type liquid crystal display element can be obtained by a method in which a polymerizable compound in a liquid crystal composition is polymerized by light irradiation or the like in a voltage applied state to form a concavo-convex shape on a substrate. In addition, before the step of curing the sealing agent for liquid crystal display elements of the present invention by heating, a step of temporarily curing the sealing agent by light irradiation may be performed, but in the sealing agent for liquid crystal display elements of the present invention, The effect of suppressing the insertion of the liquid crystal into the sealant and the liquid crystal contamination due to the sealant is particularly remarkable when the sealant is cured only by heat.

ADVANTAGE OF THE INVENTION According to this invention, the sealing agent for liquid crystal display elements which can suppress the liquid crystal contamination by the insertion to the sealing agent with a liquid crystal and liquid crystal contamination by a sealing agent, and is excellent in adhesiveness and display performance is provided. can do. Moreover, according to this invention, the vertical conduction material and liquid crystal display element which use this sealing compound for liquid crystal display elements can be provided.

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

(Synthesis of partially acrylic modified biphenyl ether type epoxy resin)
1000 parts by weight of a biphenyl ether type epoxy resin (manufactured by Nippon Steel Chemical & Materials, "YSLV80DE"), 2 parts by weight of p-methoxyphenol as a polymerization inhibitor, 2 parts by weight of triethylamine as a reaction catalyst, and 229 parts by weight of acrylic acid The mixture was refluxed and stirred at 90 ° C. while feeding air, and reacted for 5 hours. In order to adsorb ionic impurities in the reaction product, 100 parts by weight of the obtained resin was filtered through a column packed with 10 parts by weight of a natural combination of quartz and kaolin (manufactured by Hoffman Mineral Co., Ltd., “Siritin V85”). A partially acrylic-modified biphenyl ether type epoxy resin was obtained.

(Synthesis of resorcinol type epoxy acrylate)
Resorcinol type epoxy resin (manufactured by Nagase ChemteX Corporation, “Denacol EX-201”) 1000 parts by weight, p-methoxyphenol 2 parts by weight as a polymerization inhibitor, triethylamine 2 parts by weight, and 649 parts by weight of acrylic acid Then, the reaction was carried out by stirring at 90 ° C. for 5 hours while feeding air. In order to adsorb ionic impurities in the reaction product, 100 parts by weight of the obtained resin was filtered through a column packed with 10 parts by weight of a natural combination of quartz and kaolin (manufactured by Hoffman Mineral Co., Ltd., “Siritin V85”). Resorcinol type epoxy acrylate was obtained.

(Classification of silicone rubber particles)
Silicone rubber particles (manufactured by Shin-Etsu Chemical Co., Ltd., “KMP-601”) are dispersed in methanol so that the particle diameter is in the range of 5 to 8 μm with an 8 μm aperture sieve and a 5 μm aperture sieve. Wet sieve classification. The classified particles were collected and dried to obtain a silicone rubber particle classified product. As the sieve, a polyimide film having a hole with extremely high accuracy obtained by applying ultrahigh precision fine processing with a laser was used.
The obtained silicone rubber particle classification product had a maximum particle size of 8 μm as measured using a laser diffraction particle size distribution analyzer (manufactured by Malvern, “Mastersizer 2000”).
In addition, a silicone rubber particle classified product (maximum particle size) was obtained in the same manner except that wet sieve classification was performed so that the particle diameter would be in the range of 3 to 6 μm with a 6 μm aperture sieve and a 3 μm aperture sieve. 6 μm in diameter) was obtained.
Further, a silicone rubber particle classified product (maximum particle diameter 3 μm) was obtained in the same manner except that the wet sieve classification was performed so that the particle diameter was 3 μm or less with a sieve having an opening of 3 μm.

(Examples 1 to 10, Comparative Examples 1 to 3)
According to the blending ratio described in Table 1, each material was mixed using a planetary stirrer (“Shinky Co., Ltd.,“ Awatori Nertaro ”), and then mixed using three rolls. The sealants for liquid crystal display elements 1 to 10 and Comparative Examples 1 to 3 were prepared.

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

(Adhesiveness)
One part by weight of spacer particles (Sekisui Chemical Co., Ltd., “Micropearl SP-2050”) having an average particle diameter of 5 μm is used for 100 parts by weight of each sealing agent for liquid crystal display elements obtained in Examples and Comparative Examples. It was uniformly dispersed by a stirrer. A very small amount of the sealant in which the spacer particles are dispersed was taken in the center of a glass substrate (20 mm × 50 mm × thickness 0.7 mm), and the same type of glass substrate was overlaid thereon. The sealing agent for liquid crystal display elements was spread and heated at 120 ° C. for 1 hour to cure the sealing agent to obtain an adhesion test piece.
About the obtained adhesion test piece, the adhesive strength was measured using the tension gauge. The case where the adhesive strength was 200 N / cm ² or more was “◯”, the case where the adhesive strength was 150 N / cm ² or more and less than 200 N / cm ² was “Δ”, and the adhesive strength was less than 150 N / cm ² . The case was evaluated as “x” and the adhesion was evaluated.

(Insert prevention)
One part by weight of spacer particles (Sekisui Chemical Co., Ltd., “Micropearl SP-2050”) having an average particle diameter of 5 μm is used for 100 parts by weight of each sealing agent for liquid crystal display elements obtained in Examples and Comparative Examples. It was uniformly dispersed by a stirrer. The sealing agent in which the spacer particles were dispersed was filled in a dispensing syringe (“PSY-10E” manufactured by Musashi Engineering Co., Ltd.), and defoamed. The sealing agent subjected to defoaming treatment was applied with a dispenser (manufactured by Musashi Engineering Co., Ltd., “SHOTMASTER 300”) on a glass substrate having an ITO thin film and an alignment film so as to draw a rectangular frame. Subsequently, fine droplets of a liquid crystal composition containing a polymerizable compound (1% by weight of biphenyl 4,4′-diylbis (2-methylacrylate) added to MLC-6833 (Merck)) were dropped into a liquid crystal dropping device. And was applied dropwise. After another glass substrate having an ITO thin film and an alignment film is superimposed on the glass substrate on which the liquid crystal composition is dropped and applied via the sealant for a liquid crystal display element of the present invention, the pressure is reduced to 5 Pa with a vacuum bonding apparatus. To obtain a cell. The obtained cell was heated at 120 ° C. for 1 hour to cure the sealant. Next, under voltage application, a mercury lamp is used to irradiate 100 mW / cm ² of ultraviolet rays (wavelength 313 nm) for 50 seconds to polymerize the polymerizable compound in the liquid crystal composition, thereby forming a concavo-convex shape. An element (cell gap 5 μm) was obtained.
About each obtained liquid crystal display element, the shape observation of the seal pattern was performed. If the shape of the seal pattern was not disturbed by the internal liquid crystal, “◎”, if the shape of the seal pattern was slightly disturbed, “○”, the shape of the seal pattern was greatly disturbed, but the liquid crystal The anti-insertion property was evaluated as “△” for those that did not break through the seal pattern, and “X” for those where the liquid crystal broke through the seal pattern and leaked to the outside.

(Display performance of liquid crystal display elements)
About each liquid crystal display element obtained in the same manner as the evaluation of “(insertion prevention)” above, disorder of liquid crystal alignment in the vicinity of the sealing agent after applying voltage for 100 hours in an environment of 60 ° C. and 90% RH ( The display unevenness was confirmed visually.
“○” when no display unevenness was observed on the liquid crystal display element, “△” when display unevenness was found near the sealant (peripheral part) of the liquid crystal display element, and the display unevenness was not only at the peripheral part. The display performance of the liquid crystal display element was evaluated by setting “×” as the case where it extended to the center.
A liquid crystal display element with an evaluation of “◯” is a level at which there is no problem in practical use, and a liquid crystal display element with a “△” level is a level that may cause a problem depending on the display design. A display element is a level which cannot endure practical use.

Claims

Containing a curable resin, a thermosetting agent, and flexible particles having a maximum particle size of 100% or more of the cell gap of the liquid crystal display element,
The said curable resin contains the compound which has a 3 or more epoxy group in 1 molecule, The sealing compound for liquid crystal display elements characterized by the above-mentioned.
The compound having three or more epoxy groups in one molecule has a compound having three or more epoxy groups and an isocyanuric skeleton in one molecule, and / or has three or more epoxy groups in one molecule. The sealing agent for liquid crystal display elements according to claim 1, which is a glycidylamine type epoxy compound.
The sealing compound for liquid crystal display elements according to claim 2, wherein the compound having three or more epoxy groups in one molecule is a compound having three or more epoxy groups and an isocyanuric skeleton in one molecule.
The sealing agent for liquid crystal display elements of Claim 1, 2, or 3 used for sealing of the liquid crystal between the board | substrates of a PSA type liquid crystal display element.
A vertical conduction material containing the sealing agent for liquid crystal display elements according to claim 1, and conductive fine particles.
A liquid crystal display element using the sealing agent for a liquid crystal display element according to claim 1, 2, 3, or 4, or the vertical conduction material according to claim 5.