JPWO2015002067A1 - Sealant for liquid crystal dropping method, vertical conduction material, liquid crystal display element, and light-shielding flexible silicone particle - Google Patents

Abstract

An object of the present invention is to provide a sealing agent for a liquid crystal dropping method that is excellent in adhesiveness, hardly causes liquid crystal contamination, and can prevent light leakage of a liquid crystal display element. Another object of the present invention is to provide light-shielding flexible silicone particles suitable for inclusion in the sealant. The sealing agent for liquid crystal dropping method according to the present invention contains a curable resin, a polymerization initiator and / or a thermosetting agent, and light-shielding flexible particles. Moreover, the light-shielding flexible silicone particle according to the present invention is a silicone-based particle containing a light-shielding agent.

Description

The present invention relates to a sealant for a liquid crystal dropping method that is excellent in adhesiveness, hardly causes liquid crystal contamination, and can prevent light leakage of a liquid crystal display element. Moreover, this invention relates to the vertical conduction material and liquid crystal display element which are manufactured using this sealing compound for liquid crystal dropping methods. Furthermore, the present invention relates to a light-shielding flexible silicone particle.

In recent years, a method for manufacturing a liquid crystal display element such as a liquid crystal display cell has been disclosed in, for example, Patent Document 1 and Patent Document 2 from the conventional vacuum injection method from the viewpoint of shortening tact time and optimizing the amount of liquid crystal used. Such a photocurable resin, a photopolymerization initiator, a thermosetting resin, and a liquid crystal dropping method called a dropping method using a light and heat combined curing type sealant containing a thermosetting agent are being replaced.

In the dropping method, first, a rectangular seal pattern is formed on one of two transparent substrates with electrodes by dispensing. Next, a liquid crystal micro-droplet is dropped on the entire surface of the transparent substrate frame with the sealant being uncured, and the other transparent substrate is immediately overlaid, and the seal portion is irradiated with light such as ultraviolet rays to perform temporary curing. . Thereafter, heating is performed at the time of liquid crystal annealing to perform main curing, and a liquid crystal display element is manufactured. 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 a narrow frame design).
However, when a liquid crystal display element with a narrow frame design is manufactured by the dropping method, there is a portion where the light does not shine on the seal part due to the black matrix. There is a problem that the uncured photocurable resin is eluted after the temporary curing step and the liquid crystal is contaminated.

In addition, since the conventional sealant is transparent or milky white, the light that passes through the sealant cannot be shielded even with a black matrix that should originally suppress light leakage, and the contrast is lowered. It was.
Therefore, a method for imparting light shielding properties to the sealant by adding a light shielding agent has been studied. For example, Patent Documents 3 to 5 disclose sealing agents containing a light shielding agent such as a titanium black material or a carbon black material as a light shielding component.
However, such a light-shielding agent tends to aggregate after being dispersed in a resin, and dispersion stability and adhesiveness have been problems.

JP 2001-133794 A International Publication No. 02/092718 JP 2006-099027 A JP 2005-292801 A International Publication No. 2009/128470

An object of the present invention is to provide a sealing agent for a liquid crystal dropping method that is excellent in adhesiveness, hardly causes liquid crystal contamination, and can prevent light leakage of a liquid crystal display element. Moreover, an object of this invention is to provide the vertical conduction material and liquid crystal display element which are manufactured using this sealing compound for liquid crystal dropping methods. Furthermore, an object of the present invention is to provide light-shielding flexible silicone particles.

The present invention 1 is a sealing agent for a liquid crystal dropping method used for manufacturing a liquid crystal display element by a liquid crystal dropping method, and contains a curable resin, a polymerization initiator and / or a thermosetting agent, and light-shielding flexible particles. It is a sealing agent for liquid crystal dropping method.
In addition, the present invention 2 is a light-shielding flexible silicone particle comprising a silicone-based particle containing a light-shielding agent.

First, the present invention 1 will be described in detail.
The present inventor, when blending the light-shielding flexible particles in the sealing agent, when the substrate of the liquid crystal display element is bonded, the light-shielding flexible particles are a barrier between the other sealing agent components and the liquid crystal. As a result, it has been found that the sealing agent can be prevented from being eluted into the liquid crystal and light leakage of the liquid crystal display element can be prevented, and the present invention 1 has been completed.

The sealing agent for liquid crystal dropping method of the present invention 1 contains light-shielding flexible particles. The light-shielding flexible particles provide a light-shielding property to the sealing agent to prevent light leakage of the liquid crystal display element, and a barrier between the other sealing agent components and the liquid crystal when the liquid crystal display element is manufactured. Thus, it has a role of preventing the sealing agent from eluting into the liquid crystal. Further, by blending the light-shielding flexible particles, since the substrate can be prevented from shifting until the sealing agent is cured after the substrates are bonded together, the sealing agent for the liquid crystal dropping method of the present invention 1 is Excellent adhesion.

As said light-shielding flexible particle, what made the soft particle contain the light-shielding agent is preferable.
Examples of the method for containing the light-shielding agent in the soft particles include, for example, by dispersing a colorant such as a pigment or a dye as the light-shielding agent in the soft particle raw material in the soft particle production stage. A method of containing a colorant, a method of coating soft particles having no light-shielding property, and then coating the surface of the soft particles with a colorant; And the like.

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.

The silicone-based particles are preferably a silicone cured product having a diorganosiloxane unit represented by the following formula (1) as a repeating unit and having rubber elasticity.

In the formula (1), R ¹ represents an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, an aryl group such as a phenyl group or a tolyl group, an alkenyl group such as a vinyl group or an allyl group, β -Aralkyl groups such as phenylethyl group and β-phenylpropyl group, hydrocarbon groups in which some or all of hydrogen atoms of these hydrocarbon groups are substituted with halogen atoms such as chlorine and fluorine, epoxy groups, amino groups Reactive group-containing organic groups such as a mercapto group, an acryloxy group, and a methacryloxy group. a is preferably from 5 to 5000, and more preferably from 10 to 1000.

The reaction mechanism of the curing reaction to form the silicone particles, condensation or methoxy silyl group and (≡SiOCH ₃₎ and the like hydroxy silyl group (≡SiOH), mercapto silyl group and (≡SiSH) vinylsilyl (≡SiCH ═CH ₂ ) and radical addition reaction with vinylsilyl group (≡SiCH═CH ₂ ) and ≡SiH group, etc. (hydrosilylation) addition from the point of reactivity and reaction process It is preferable to use a reaction. That is, in the present invention, it is preferable to use a composition in which (a) a vinyl group-containing organopolysiloxane and (b) an organohydrogenpolysiloxane are subjected to an addition reaction in the presence of (c) a platinum-based catalyst.
Specific examples of such component (a) include compounds represented by the following formula (2).

In formula (2), R ¹ is the same as R ¹ in the formula (1) is preferably one having no aliphatic unsaturated bond. b and c are 0, 1, 2 or 3, and b + c = 3, d is a positive number, e is 0 or a positive number, and 2b + e ≧ 2.

Examples of the organohydrogenpolysiloxane of the component (b) include compounds represented by the following formula (3).

In the above formula (3), R ² is an unsubstituted or substituted monovalent hydrocarbon group bonded to a silicon atom having usually 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms, excluding an aliphatic unsaturated bond. As the unsubstituted or substituted monovalent hydrocarbon group in R ² , for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group Alkyl groups such as hexyl group, cyclohexyl group, octyl group, nonyl group, decyl group, aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group, benzyl group, phenylethyl group, phenylpropyl group, etc. Aralkyl groups of these groups, or those in which some or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine, bromine, chlorine, etc., such as chloromethyl groups, chloropro Group, bromoethyl group, trifluoropropyl group and the like. The unsubstituted or substituted monovalent hydrocarbon group for R ² is preferably an alkyl group or an aryl group, and more preferably a methyl group or a phenyl group. F is 0.7 to 2.1, g is 0.001 to 1.0, and f + g is a positive number satisfying 0.8 to 3.0. Preferably, f is 1.0. -2.0, g is 0.01-1.0, and f + g is 1.5-2.5.
Specific examples of such component (b) include compounds represented by the following formula (4).

In Formula (4), R ¹ is the same as R ¹ in the formula (1) is preferably one having no aliphatic unsaturated bond. m is 0 or 1, n is 2 or 3, and m + n = 3, p is 0 or a positive number, q is 0 or a positive number, and 2m + q ≧ 2.

The component (c) platinum-based catalyst is a catalyst that causes an addition reaction between a vinyl group bonded to a silicon atom in the component (a) and a hydrogen atom (SiH group) bonded to a silicon atom in the component (b). Yes, for example, platinum-supported carbon or silica, chloroplatinic acid, platinum-olefin complex, platinum-alcohol complex, platinum-phosphorus complex, platinum coordination compound and the like.

As a method for producing the silicone-based particles using the components (a) to (c), the component (a) and the component (b) may be reacted in the presence of the component (c) and cured. Although not limited, For example, the method of hardening (a) component and (b) component in high temperature spray drying, the method of hardening in an organic solvent, the method of hardening after making this into an emulsion, etc. are mentioned. Further, in order to further improve the dispersibility of the silicone particles, the surface of the silicone particles may be coated with a polyorganosilsesquioxane resin as necessary.

As described above, the light-shielding flexible particles are obtained by dispersing a colorant such as a pigment or a dye as the light-shielding agent in the raw material of the flexible particles at the production stage of the soft particles. It can produce by the method of making it contain. Specifically, a colorant such as a pigment or a dye is previously dispersed or dissolved in the components (a) to (c), and then a curing reaction is performed, whereby silicone-based particles having light shielding properties can be obtained. When the colorant is dispersed in the components (a) to (c), it is preferable to add a surfactant or a dispersant having an affinity for both the silicone component and the colorant. By applying a colorant as a light-shielding agent before the curing reaction, the colorant is less likely to elute or peel off from the particles, and liquid crystal contamination can be suppressed.

In addition, as described above, the light-shielding flexible particles are prepared by producing a soft particle having no light-shielding property and then coating the surface of the soft particle with a colorant, or producing a soft particle having no light-shielding property. Then, it can also be produced by a method in which the soft particles absorb the colorant. Specifically, the light-shielding property is imparted by dispersing the silicone-based particles having no light-shielding property in a medium in which the colorant is dissolved and stirring for a predetermined time to fix the colorant to the silicone-based particles. Further, light shielding properties can be imparted by fixing a colorant on the surface of the silicone-based particles having no light shielding properties using a compounding device such as a hybridizer or a theta composer.
Further, a method of adsorbing a polymerizable colorant on the surface of the silicone-based particles that do not have light shielding properties may be used. That is, light-shielding properties can be imparted by precipitating a polymer having a skeleton or a functional group that absorbs light of a specific wavelength on the surface of silicone-based particles that do not have light-shielding properties. Specifically, in the presence of silicone particles that do not have light-shielding properties, the polymer as a raw material for the polymer is subjected to emulsion polymerization, soap-free polymerization, dispersion polymerization, or the like, thereby forming the polymer on the surface of the silicone-based particles. Can be deposited.
Examples of the polymer deposited on the surface of the silicone particles include polymers obtained by polymerizing acetylene and derivatives thereof, aniline and derivatives thereof, furan and derivatives thereof, pyrrole and derivatives thereof, thiophene and derivatives thereof, and the like. Especially, the polypyrrole which is excellent in black expression property is preferable.

Commercially available silicone particles can also be used as the silicone particles having no light-shielding property.
Examples of the commercially available silicone particles include KMP-594, KMP-597, KMP-598, KMP-600, KMP-601, KMP-602 (manufactured by Shin-Etsu Silicone), Trefil E-506S, EP- 9215 (manufactured by Toray Dow Corning Co., Ltd.), etc., can be classified and used. The said silicone type particle | grains which do not have light-shielding property 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.

Examples of the monomer that is a raw material for forming the (meth) acrylic particles include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and hexyl (meth). Alkyl (meth) such as acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, etc. ) Acrylates, oxygen-containing (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, glycerol (meth) acrylate, polyoxyethylene (meth) acrylate, glycidyl (meth) acrylate, etc. And, (meth) nitrile and containing monomers such as acrylonitrile, trifluoromethyl (meth) acrylate, monofunctional monomer such as a fluorine-containing (meth) acrylates such as pentafluoroethyl (meth) acrylate. Among these, alkyl (meth) acrylates are preferable because the Tg of the homopolymer is low and the deformation amount when a 1 g load is applied can be increased.
In the present specification, the “(meth) acrylate” means acrylate or methacrylate.

Moreover, in order to give a crosslinked structure, tetramethylol methane tetra (meth) acrylate, tetramethylol methane tri (meth) acrylate, tetramethylol methane di (meth) acrylate, trimethylol propane tri (meth) acrylate, 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 (meth) It may be used polyfunctional monomers acrylate. 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.

With respect to the use amount of the crosslinkable monomer, the preferable lower limit is 1% by weight and the preferable upper limit is 90% by weight in the whole monomer. When the amount of the crosslinkable monomer used is 1% by weight or more, the solvent resistance is improved, and when kneaded with various sealant raw materials, problems such as swelling do not occur and the particles are easily dispersed uniformly. When the amount of the crosslinkable monomer used is 90% by weight or less, the recovery rate can be lowered, and problems such as springback are less likely to occur. A more preferable lower limit of the amount of the crosslinkable monomer used is 3% by weight, and a more preferable upper limit is 80% by weight.

In addition to these acrylic monomers, styrene monomers such as styrene and α-methylstyrene, vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, and propyl vinyl ether, vinyl acetate, vinyl butyrate, and laurin. Acid vinyl esters such as vinyl acid and vinyl stearate, unsaturated hydrocarbons such as ethylene, propylene, isoprene and butadiene, halogen-containing monomers such as vinyl chloride, vinyl fluoride and chlorostyrene, triallyl (iso ) Using monomers such as cyanurate, triallyl trimellitate, divinylbenzene, diallylphthalate, diallylacrylamide, diallyl ether, γ- (meth) acryloxypropyltrimethoxysilane, trimethoxysilylstyrene, vinyltrimethoxysilane Good .

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 vinyl particles and the urethane particles can also be provided with light-shielding properties by the same method as the silicone particles.

The preferable lower limit of the hardness of the light-shielding flexible particles is 10, and the preferable upper limit is 50. When the hardness of the light-shielding flexible particles exceeds 50, the obtained sealing agent for liquid crystal dropping method may be inferior in adhesiveness, or a gap defect may occur in the obtained liquid crystal display element. The more preferable lower limit of the hardness of the light-shielding flexible particles is 20, and the more preferable upper limit is 40.
In addition, in this specification, the hardness of the said light-shielding flexible particle means the durometer A hardness measured by the method based on JISK6253.

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

The titanium black is a substance having a higher transmittance in the vicinity of the ultraviolet region, particularly for light with a wavelength of 370 to 450 nm, compared to the average transmittance for light with a wavelength of 300 to 800 nm. That is, the above-mentioned titanium black is a light-shielding agent having a property of providing light-shielding properties to light-shielding flexible particles by sufficiently shielding light having a wavelength in the visible light region, while transmitting light having a wavelength in the vicinity of the ultraviolet region. . Therefore, as a polymerization initiator to be described later, a liquid crystal dropping method seal according to the first aspect of the present invention can be used by using a material capable of initiating a reaction with light having a wavelength (370 to 450 nm) that increases the transmittance of the titanium black. The photocurability of the agent can be further increased. On the other hand, the light shielding agent contained in the soft particles 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.
Further, since the sealing agent for liquid crystal dropping method using titanium black as a light shielding agent contained in the flexible particles has sufficient light shielding properties, the obtained liquid crystal display element has high contrast without leaking light. In addition, the image display quality is excellent.

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

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

The preferable lower limit of the primary particle diameter of the light-shielding agent contained in the flexible particles is 50 nm, and the preferable upper limit is 500 nm. If the primary particle size of the light-shielding agent contained in the flexible particles is less than 50 nm, the viscosity and thixo ratio may increase, secondary aggregation may occur, and the dispersibility in the particles may be significantly reduced. is there. When the primary particle diameter of the light-shielding agent contained in the soft particles exceeds 500 nm, the dispersibility in the particles may be reduced, or the particles themselves may be hard and easily broken. The more preferable lower limit of the primary particle diameter of the light-shielding agent contained in the flexible particles is 70 nm, and the more preferable upper limit is 300 nm.

The preferred lower limit of the content of the light-shielding agent contained in the flexible particles is 2% by weight and the preferred upper limit is 30% by weight with respect to the entire light-shielding flexible particles. If the content of the light shielding agent contained in the soft particles is less than 2% by weight, sufficient light shielding properties may not be obtained. If the content of the light-shielding agent contained in the flexible particles exceeds 30% by weight, the particles themselves may be hard and easily cracked. The more preferable lower limit of the content of the light shielding agent contained in the soft particles is 5% by weight, and the more preferable upper limit is 20% by weight.

The sealing agent for liquid crystal dropping method of the present invention 1 is used for production of a liquid crystal display element by a liquid crystal dropping method.
The light-shielding flexible particles preferably have a maximum particle size of 100% or more of the cell gap of the liquid crystal display element. If the maximum particle size of the light-shielding flexible particles is less than 100% of the cell gap of the liquid crystal display element, seal breakage and liquid crystal contamination may not be sufficiently suppressed. The maximum particle diameter of the light-shielding flexible particles is 100% or more of the cell gap of the liquid crystal display element, and more preferably 5 μm or more.
Moreover, the preferable upper limit of the maximum particle diameter of the said light-shielding flexible particle | grain is 20 micrometers. When the maximum particle diameter of the light-shielding flexible particles exceeds 20 μm, spring back occurs, and the obtained liquid crystal dropping method sealant is inferior in adhesiveness, or the obtained liquid crystal display element has a gap defect. Sometimes. A more preferable upper limit of the maximum particle diameter of the light-shielding flexible particles is 15 μm.
Furthermore, the maximum particle diameter of the light-shielding flexible particles is preferably 2.6 times or less of the cell gap. When the maximum particle diameter of the light-shielding flexible particles exceeds 2.6 times the cell gap, a springback occurs, and the resulting liquid crystal dropping method sealant is inferior in adhesiveness, or the obtained liquid crystal display element A gap defect may occur. A more preferable upper limit of the maximum particle diameter of the light-shielding flexible particles is 2.2 times the cell gap, and a more preferable upper limit is 1.7 times the cell gap.
In the present specification, the maximum particle size of the light-shielding flexible particles and the average particle size described later are obtained by measuring the particles before blending with the sealant using a laser diffraction particle size distribution measuring device. Mean value. As the laser diffraction type distribution measuring device, Mastersizer 2000 (manufactured by Malvern) or the like can be used. Moreover, since the cell gap of a liquid crystal display element changes with display elements, it is not limited, The cell gap of a general liquid crystal display element is 2 micrometers-10 micrometers.

In the light-shielding flexible particles, the content ratio of particles having a particle diameter of 5 μm or more in the particle size distribution of the light-shielding flexible particles measured by the laser diffraction distribution measuring apparatus is 60% or more by volume frequency. preferable. When the content ratio of particles having a particle diameter of 5 μm or more is less than 60% in terms of volume frequency, seal breakage and liquid crystal contamination may not be sufficiently suppressed. The content ratio of particles having a particle diameter of 5 μm or more is more preferably 80% or more.

The light-shielding flexible particles have a particle size distribution of 70% or more of the cell gap of the liquid crystal display element from the viewpoint of exerting the effect of suppressing the occurrence of seal break and liquid crystal contamination. % Or more, and more preferably composed only of particles having a cell gap of 100% or more of the liquid crystal display element.

The preferable lower limit of the average particle diameter of the light-shielding flexible particles is 2 μm, and the preferable upper limit is 15 μm. If the average particle diameter of the light-shielding flexible particles is less than 2 μm, the elution of the sealant into the liquid crystal may not be sufficiently prevented. When the average particle diameter of the light-shielding flexible particles exceeds 15 μm, the obtained liquid crystal dropping method sealing agent may be inferior in adhesion, or the obtained liquid crystal display element may have a gap defect. The more preferable lower limit of the average particle diameter of the light-shielding flexible particles is 4 μm, and the more preferable upper limit is 12 μm.

As the light-shielding flexible particles, two or more kinds of light-shielding flexible particles having different maximum particle diameters may be mixed and used. That is, the light-shielding flexible particles having a maximum particle diameter of less than 100% of the cell gap of the liquid crystal display element and the light-shielding flexible particles having a maximum particle diameter of 100% or more of the cell gap of the liquid crystal display element may be mixed and used. Good.

The coefficient of variation (hereinafter also referred to as “CV value”) of the light-shielding flexible particles is preferably 30% or less. When the CV value of the particle size of the light-shielding flexible particles exceeds 30%, a cell gap defect may be caused. The CV value of the particle diameter of the light-shielding flexible particles is more preferably 28% or less.
In the present specification, the CV value of the particle diameter is a numerical value obtained by the following formula.
CV value of particle diameter (%) = (standard deviation of particle diameter / average particle diameter) × 100

Even if the light-shielding flexible particles are those having a maximum particle diameter, an average particle diameter, or a CV value that are outside the above-described ranges, by classifying, the maximum particle diameter, the average particle diameter, or the CV value is within the above-described range. can do. In addition, light-shielding flexible particles having a particle diameter of less than 100% of the cell gap of the liquid crystal display element do not contribute to the suppression of the occurrence of seal breaks and liquid crystal contamination, and may increase the thixo value when added to a sealant. Therefore, it is preferable to remove by classification.
Examples of the method for classifying the light-shielding flexible particles include wet classification and dry classification. Of these, wet classification is preferable, and wet sieving classification is more preferable.

The light-shielding flexible particles have L1 as the compression displacement from the load value for the origin to the reverse load value when the load is applied, and unload from the reverse load value to the load value for the origin when the load is released 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 light-shielding flexible particles exceeds 80%, the function of preventing the sealing agent from eluting into the liquid crystal may be lowered. A more preferable upper limit of the recovery rate of the light-shielding flexible particles is 70%, and a more preferable upper limit is 60%.
The recovery rate of the light-shielding flexible particles can be derived by applying a constant load (1 g) to each particle and analyzing the recovery behavior after removing the load using a micro compression tester. it can.

The light-shielding 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. If the 1 g strain of the light-shielding flexible particles is less than 30%, the function of preventing the sealing agent from eluting into the liquid crystal may be lowered. A more preferable lower limit of 1 g strain of the light-shielding flexible particles is 40%.
The 1 g strain of the light-shielding flexible particles can be measured by applying a 1 g load to each particle using a micro compression tester and measuring the amount of displacement at that time.

The light-shielding 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. If the breaking strain of the light-shielding flexible particles is less than 50%, the function of preventing the sealing agent from eluting into the liquid crystal may be lowered. A more preferable lower limit of the fracture strain of the light-shielding flexible particles is 60%.
The breaking strain of the light-shielding flexible particles can be measured by applying a load to each particle using a micro compression tester and measuring the amount of 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 light-shielding flexible particles have a preferable lower limit of the glass transition temperature of −200 ° C. and a preferable upper limit of 40 ° C. If the glass transition temperature of the light-shielding flexible particles is −200 ° C. or higher, the lower the better the effect of suppressing seal break and liquid crystal contamination, but if it is less than −200 ° C., there is a problem in particle handling. In some cases, the sealing agent is easily crushed during heating, and the sealing agent in the middle of curing comes into contact with the liquid crystal to cause liquid crystal contamination. When the glass transition temperature of the light-shielding flexible particles exceeds 40 ° C., a gap defect may occur. The minimum with a more preferable glass transition temperature of the said light-shielding flexible particle | grain is -150 degreeC, and a more preferable upper limit is 35 degreeC.
In addition, the glass transition temperature of the said light-shielding flexible particle shows the value measured by the differential scanning calorimetry (DSC) based on "the transition temperature measuring method of plastics" of JISK7121.

The light-shielding flexible particles preferably have a blackening degree of 10% or less, and more preferably 5% or less. The light shielding property of the light-shielding flexible particles is preferably as low as possible, and there is no particular lower limit to the blackness of the light-shielding flexible particles, but it is usually 0.05% or more.
In addition, the blackening degree of the said light-shielding flexible particle | grain can be evaluated by the maximum value of the spectral transmittance in all visible light region wavelengths of 400-700 nm. Specifically, a 1 mm-thick flaky polymer having the same composition as the particles to be evaluated was prepared as a sample for measuring the degree of blackening, and the spectrophotometer was used to measure the spectrophotometer at all wavelengths in the visible light region. It can be obtained by measuring the transmittance.

The content of the light-shielding flexible particles is preferably 3 parts by weight with respect to 100 parts by weight of the curable resin, and 70 parts by weight with respect to the preferable upper limit. If the content of the light-shielding flexible particles is less than 3 parts by weight, the sealing agent may not be sufficiently prevented from being eluted into the liquid crystal. When content of the said light-shielding flexible particle | grain exceeds 70 weight part, the sealing compound for liquid crystal dropping methods obtained may become inferior to adhesiveness. A more preferred lower limit of the content of the light-shielding flexible particles is 5 parts by weight, a more preferred upper limit is 60 parts by weight, a still more preferred lower limit is 10 parts by weight, and a still more preferred upper limit is 50 parts by weight.

The sealing agent for liquid crystal dropping method of the present invention 1 contains a curable resin.
The curable resin preferably contains a (meth) acrylic resin.
Since the sealing agent for liquid crystal dropping method of the present invention 1 can be quickly cured, it contains a (meth) acrylic resin as a curable resin and a radical polymerization initiator described later as a polymerization initiator. It is possible to quickly cure the liquid crystal dropping method sealing agent of the present invention 1 only by heating, and even in a liquid crystal display element with a narrow frame design, the occurrence of liquid crystal contamination can be sufficiently suppressed. Therefore, it is more preferable to contain a (meth) acrylic resin and a thermal radical polymerization initiator described later.
More preferably, the curable resin contains an epoxy (meth) acrylate.
In the present specification, the “(meth) acrylic resin” means a resin having a (meth) acryloyl group, and the “(meth) acryloyl group” means an acryloyl group or a methacryloyl group. The “epoxy (meth) acrylate” means a compound obtained by reacting all epoxy groups in the epoxy resin with (meth) acrylic acid.

Examples of the epoxy resin that is a raw material for synthesizing the epoxy (meth) acrylate include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and 2,2′-diallyl bisphenol A type epoxy resin. , Hydrogenated bisphenol type epoxy resin, propylene oxide added bisphenol A type epoxy resin, resorcinol type epoxy resin, biphenyl type epoxy resin, sulfide type epoxy resin, diphenyl ether type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, phenol Novolac epoxy resin, ortho-cresol novolac epoxy resin, dicyclopentadiene novolac epoxy resin, biphenyl novolac epoxy resin, naphtha Emissions phenol novolak type epoxy resin, glycidyl amine type epoxy resin, alkyl polyol type epoxy resin, rubber modified epoxy resin, glycidyl ester compounds, bisphenol A type episulfide resins.

As what is marketed among the said bisphenol A type epoxy resins, jER828EL, jER1001, jER1004 (all are the Mitsubishi Chemical company make), Epicron 850-S (made by DIC company), etc. are mentioned, for example.
As what is marketed among the said bisphenol F-type epoxy resins, jER806, jER4004 (all are the Mitsubishi Chemical company make) etc. are mentioned, for example.
As what is marketed among the said bisphenol S-type epoxy resins, Epicron EXA1514 (made by DIC Corporation) etc. are mentioned, for example.
As what is marketed among the said 2,2'- diallyl bisphenol A type epoxy resins, RE-810NM (made by Nippon Kayaku Co., Ltd.) etc. are mentioned, for example.
As what is marketed among the said hydrogenated bisphenol type | mold epoxy resins, Epicron EXA7015 (made by DIC Corporation) etc. are mentioned, for example.
As what is marketed among the said propylene oxide addition bisphenol A type epoxy resins, EP-4000S (made by ADEKA) etc. are mentioned, for example.
As what is marketed among the said resorcinol type epoxy resins, EX-201 (made by Nagase ChemteX Corporation) etc. are mentioned, for example.
As what is marketed among the said biphenyl type epoxy resins, jERYX-4000H (made by Mitsubishi Chemical Corporation) etc. are mentioned, for example.
As what is marketed among the said sulfide type epoxy resins, YSLV-50TE (made by Nippon Steel & Sumikin Chemical Co., Ltd.) etc. are mentioned, for example.
As what is marketed among the said diphenyl ether type epoxy resins, YSLV-80DE (made by Nippon Steel & Sumikin Chemical Co., Ltd.) etc. are mentioned, for example.
As what is marketed among the said dicyclopentadiene type epoxy resins, EP-4088S (made by ADEKA) etc. are mentioned, for example.
As what is marketed among the said naphthalene type | mold epoxy resins, Epicron HP4032, Epicron EXA-4700 (all are the products made from DIC) etc. are mentioned, for example.
As what is marketed among the said phenol novolak-type epoxy resins, Epicron N-770 (made by DIC Corporation) etc. are mentioned, for example.
As what is marketed among the said ortho cresol novolak-type epoxy resins, Epicron N-670-EXP-S (made by DIC) etc. are mentioned, for example.
As what is marketed among the said dicyclopentadiene novolak-type epoxy resins, epiclone HP7200 (made by DIC) etc. are mentioned, for example.
As what is marketed among the said biphenyl novolak-type epoxy resins, NC-3000P (made by Nippon Kayaku Co., Ltd.) etc. are mentioned, for example.
As what is marketed among the said naphthalene phenol novolak-type epoxy resins, ESN-165S (made by Nippon Steel & Sumikin Chemical Co., Ltd.) etc. are mentioned, for example.
As what is marketed among the said glycidyl amine type epoxy resins, jER630 (made by Mitsubishi Chemical Corporation), Epicron 430 (made by DIC Corporation), TETRAD-X (made by Mitsubishi Gas Chemical Co., Inc.) etc. are mentioned, for example.
Examples of commercially available alkyl polyol type epoxy resins include ZX-1542 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), Epiklon 726 (manufactured by DIC Corporation), Epolite 80MFA (manufactured by Kyoeisha Chemical Co., Ltd.), Denacol EX-611. (Manufactured by Nagase ChemteX Corporation).
Examples of commercially available rubber-modified epoxy resins include YR-450, YR-207 (all manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), Epolide PB (manufactured by Daicel Corporation), and the like.
As what is marketed among the said glycidyl ester compounds, Denacol EX-147 (made by Nagase ChemteX Corporation) etc. is mentioned, for example.
As what is marketed among the said bisphenol A type | mold episulfide resin, jERYL-7000 (made by Mitsubishi Chemical Corporation) etc. are mentioned, for example.
Other commercially available epoxy resins include, for example, YDC-1312, YSLV-80XY, YSLV-90CR (all manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), XAC4151 (manufactured by Asahi Kasei Co., Ltd.), jER1031, jER1032 (any And Mitsubishi Chemical Corporation), EXA-7120 (DIC Corporation), TEPIC (Nissan Chemical Corporation), and the like.

Examples of commercially available epoxy (meth) acrylates include, for example, EBECRYL860, EBECRYL3200, EBECRYL3201, EBECRYL3412, EBECRYL3600, EBECRYL3700, EBECRYL3701, EBECRYL3702, EBECRYL3703, EBECRY3603 EA-1010, EA-1020, EA-5323, EA-5520, EA-CHD, EMA-1020 (all manufactured by Shin-Nakamura Chemical Co., Ltd.), epoxy ester M-600A, epoxy ester 40EM, epoxy ester 70PA, epoxy Ester 200PA, epoxy ester 80MFA Epoxy ester 3002M, Epoxy ester 3002A, Epoxy ester 1600A, Epoxy ester 3000M, Epoxy ester 3000A, Epoxy ester 200EA, Epoxy ester 400EA (all manufactured by Kyoeisha Chemical Co., Ltd.), Denacol acrylate DA-141, Denacol acrylate DA-314, Denacol acrylate DA-911 (all manufactured by Nagase ChemteX Corporation) and the like.

Examples of other (meth) acrylic resins other than the epoxy (meth) acrylate include ester compounds obtained by reacting a compound having a hydroxyl group with (meth) acrylic acid, and (meth) acrylic acid having a hydroxyl group in isocyanate. Examples thereof include urethane (meth) acrylate obtained by reacting a derivative.

Among the ester compounds obtained by reacting the above (meth) acrylic acid with a compound having a hydroxyl group, examples of monofunctional compounds include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4 -Hydroxybutyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isobornyl (Meth) acrylate, cyclohexyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, methoxyethylene glycol (meth) acrylate, 2-ethoxyethyl (meth) acrylate, tetrahydroph Furyl (meth) acrylate, benzyl (meth) acrylate, ethyl carbitol (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, 1H, 1H, 5H-octafluoropentyl (meth) acrylate, imide (meth) acrylate, Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhex Ru (meth) acrylate, n-octyl (meth) acrylate, isononyl (meth) acrylate, isomyristyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, bicyclopentenyl (meth) Acrylate, isodecyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, 2 -(Meth) acryloyloxyethyl 2-hydroxypropyl phthalate, glycidyl (meth) acrylate, 2- (meth) acryloyloxyethyl phosphate and the like.

Examples of the bifunctional one of the ester compounds include 1,4-butanediol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, 2-n-butyl-2-ethyl-1,3-propanediol di (meth) acrylate, dipropylene glycol di (Meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (me ) Acrylate, propylene oxide-added bisphenol A di (meth) acrylate, ethylene oxide-added bisphenol A di (meth) acrylate, ethylene oxide-added bisphenol F di (meth) acrylate, dimethylol dicyclopentadienyl di (meth) acrylate, 1,3 -Butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethylene oxide-modified isocyanuric acid di (meth) acrylate, 2-hydroxy-3- (meth) acryloyloxypropyl (meth) acrylate, carbonate diol di ( (Meth) acrylate, polyether diol di (meth) acrylate, polyester diol di (meth) acrylate, polycaprolactone diol di (meth) acrylate Polybutadiene di (meth) acrylate.

Examples of the ester compound having three or more functional groups include pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, propylene oxide-added trimethylolpropane tri (meth) acrylate, and ethylene oxide-added trimethylolpropane tri. (Meth) acrylate, caprolactone-modified trimethylolpropane tri (meth) acrylate, ethylene oxide-added isocyanuric acid tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ditrimethylolpropane tetra (meth) ) Acrylate, pentaerythritol tetra (meth) acrylate, glycerin tri (meth) acrylate, propylene oxide De additional glycerin tri (meth) acrylate, tris (meth) acryloyloxyethyl phosphate, and the like.

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

As an isocyanate used as the raw material of the urethane (meth) acrylate, for example, isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diphenylmethane-4,4 ′ Diisocyanate (MDI), hydrogenated MDI, polymeric MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate, tolidine diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, tris (isocyanate) Phenyl) thiophosphate, tetramethylxylene diisocyanate, 1,6,10-undecane triisocyanate Doors and the like.

Examples of the isocyanate include, for example, a reaction between a polyol such as ethylene glycol, glycerin, sorbitol, trimethylolpropane, (poly) propylene glycol, carbonate diol, polyether diol, polyester diol, polycaprolactone diol and excess isocyanate. The resulting chain-extended isocyanate compound can also be used.

Examples of the (meth) acrylic acid derivative having a hydroxyl group that is a raw material for the urethane (meth) acrylate include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl (meth). Commercial products such as acrylate and 2-hydroxybutyl (meth) acrylate, and divalent alcohols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and polyethylene glycol Epoxy (meth) acrylates such as mono (meth) acrylate or di (meth) acrylate of trivalent alcohols such as mono (meth) acrylate, trimethylolethane, trimethylolpropane and glycerin, and bisphenol A type epoxy acrylate Etc. The.

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

The (meth) acrylic resin preferably has a hydrogen-bonding unit such as —OH group, —NH— group, and —NH ₂ group from the viewpoint of suppressing adverse effects on the liquid crystal.
The (meth) acrylic resin preferably has 2 to 3 (meth) acryloyl groups in the molecule because of its high reactivity.

The said curable resin may contain an epoxy resin further in order to improve the adhesiveness of the sealing compound for liquid crystal dropping methods obtained.
As said epoxy resin, the epoxy resin used as the raw material for synthesize | combining the said epoxy (meth) acrylate, a partial (meth) acryl modified epoxy resin, etc. are mentioned, for example. In the present specification, the partial (meth) acryl-modified epoxy resin means a resin having one or more epoxy groups and (meth) acryloyl groups in one molecule, for example, two or more epoxy groups. It can be obtained by reacting a part of the epoxy group of the resin having a methacrylic acid with (meth) acrylic acid.

Examples of commercially available partial (meth) acrylic-modified epoxy resins include UVACURE 1561 (manufactured by Daicel Ornex).

When the epoxy resin is contained as the curable resin, a preferable upper limit of the ratio of the epoxy group to the total amount of the (meth) acryloyl group and the epoxy group in the entire curable resin is 50 mol%. When the ratio of the epoxy group exceeds 50 mol%, the resulting liquid crystal dropping method sealing agent is highly soluble in liquid crystals, causing liquid crystal contamination, and the resulting liquid crystal display element may be inferior in display performance. is there. A more preferable upper limit of the ratio of the epoxy group is 20 mol%.

The sealing agent for liquid crystal dropping method of the present invention 1 contains a polymerization initiator and / or a thermosetting agent.
Especially, it is preferable to contain a radical polymerization initiator as a polymerization initiator. Springback is influenced not only by the maximum particle diameter of the light-shielding flexible particles but also by the curing rate of the sealant. Since the radical polymerization initiator can significantly increase the curing rate as compared with the thermosetting agent, the use of the radical polymerization initiator in combination with the light-shielding flexible particles generates springback that is likely to occur due to the light-shielding flexible particles. It is possible to further improve the effect of suppressing the above.

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.
As described above, the radical polymerization initiator has a much faster curing rate than the thermosetting agent. Therefore, by using the radical polymerization initiator, the occurrence of seal breaks and liquid crystal contamination is suppressed, and the light shielding is performed. The spring back that is easily generated by the flexible particles can be suppressed.
Especially, since the sealing agent for liquid crystal dropping methods obtained can be hardened | cured rapidly with a heat | fever, it is preferable that the said radical polymerization initiator contains a thermal radical polymerization initiator.
As said thermal radical polymerization initiator, what consists of an azo compound, an organic peroxide, etc. is mentioned, for example. Among these, a polymer azo initiator composed of a polymer azo compound is preferable.
In the present specification, the polymer azo initiator means a compound having an azo group and generating a radical capable of curing a (meth) acryloyloxy group by heat and having a number average molecular weight of 300 or more. .

The preferable lower limit of the number average molecular weight of the polymeric azo initiator is 1000, and the preferable upper limit is 300,000. When the number average molecular weight of the polymer azo initiator is less than 1000, the polymer azo initiator may adversely affect the liquid crystal. When the number average molecular weight of the polymeric azo initiator exceeds 300,000, mixing with the curable resin may be difficult. The more preferable lower limit of the number average molecular weight of the polymeric azo initiator 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 by measuring with 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 initiator include those having a structure in which a plurality of units such as polyalkylene oxide and polydimethylsiloxane are bonded via an azo group.
As the polymer azo initiator having a structure in which a plurality of units such as polyalkylene oxide are bonded via the azo group, those having a polyethylene oxide structure are preferable. Examples of such a polymeric azo initiator include polycondensates of 4,4′-azobis (4-cyanopentanoic acid) and polyalkylene glycol, and 4,4′-azobis (4-cyanopentanoic acid). Examples include polycondensates of polydimethylsiloxane having a terminal amino group, and specific examples include VPE-0201, VPE-0401, VPE-0601, VPS-0501, and VPS-1001 (all of which are Wako Pure Chemical Industries, Ltd.). Manufactured) and the like.

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

Examples of the photo radical polymerization initiator include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, thioxanthones, and the like.

Examples of commercially available photo radical polymerization initiators include IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACUREOXE01, DAROCUR TPO (all from BASF M Examples include benzoin ethyl ether and benzoin isopropyl ether (all of which are manufactured by Tokyo Chemical Industry Co., Ltd.).

Moreover, a cationic polymerization initiator can also be used as the polymerization initiator.
As the cationic polymerization initiator, a photocationic polymerization initiator can be suitably 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 content of the polymerization initiator is preferably 0.1 parts by weight and preferably 30 parts by weight with respect to 100 parts by weight of the curable resin. If the content of the polymerization initiator is less than 0.1 parts by weight, the obtained sealing agent for liquid crystal dropping method may not be sufficiently cured. When content of the said polymerization initiator exceeds 30 weight part, the storage stability of the sealing compound for liquid crystal dropping methods obtained may fall. A more preferable lower limit of the content of the polymerization initiator is 1 part by weight, a more preferable upper limit is 10 parts by weight, and a still more preferable upper limit is 5 parts by weight.

Examples of the thermosetting agent include organic acid hydrazides, imidazole derivatives, amine compounds, polyhydric phenol compounds, acid anhydrides, and the like. Among these, solid organic acid hydrazide is preferably used.

Examples of the solid organic acid hydrazide include 1,3-bis (hydrazinocarboethyl) -5-isopropylhydantoin, sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, malonic acid dihydrazide, and the like. Examples thereof include Amicure VDH, Amicure UDH (all manufactured by Ajinomoto Fine Techno Co., Ltd.), SDH, IDH, ADH (all manufactured by Otsuka Chemical Co., Ltd.), MDH (manufactured by Nippon Finechem Co., Ltd.), and the like.

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 less than 1 part by weight, the resulting sealing agent for liquid crystal dropping method may not be sufficiently cured. When content of the said thermosetting agent exceeds 50 weight part, the viscosity of the sealing compound for liquid crystal dropping methods obtained will become high too much, and applicability | paintability may worsen. The upper limit with more preferable content of the said thermosetting agent is 30 weight part.

It is preferable that the sealing compound for liquid crystal dropping method of this invention 1 contains a hardening accelerator. By using the curing accelerator, the sealing agent can be sufficiently cured without heating at a high temperature.

Examples of the curing accelerator include polyvalent carboxylic acids having an isocyanuric ring skeleton and epoxy resin amine adducts. Specific examples include tris (2-carboxymethyl) isocyanurate and tris (2-carboxyl). And ethyl) isocyanurate, tris (3-carboxypropyl) isocyanurate, and bis (2-carboxyethyl) isocyanurate.

The content of the curing accelerator is preferably 0.1 parts by weight and preferably 10 parts by weight with respect to 100 parts by weight of the curable resin. If the content of the curing accelerator is less than 0.1 parts by weight, the resulting liquid crystal dropping method sealing agent may not be sufficiently cured, or heating at a high temperature may be required for curing. is there. When content of the said hardening accelerator exceeds 10 weight part, the sealing compound for liquid crystal dropping methods obtained may become inferior to adhesiveness.

The sealing agent for the liquid crystal dropping method of the present invention 1 preferably contains a filler for the purpose of improving the viscosity, improving the adhesion due to the stress dispersion effect, improving the linear expansion coefficient, improving the moisture resistance of the cured product, and the like. .

Examples of the filler include talc, asbestos, silica, diatomaceous earth, smectite, bentonite, calcium carbonate, magnesium carbonate, alumina, montmorillonite, zinc oxide, iron oxide, magnesium oxide, tin oxide, titanium oxide, magnesium hydroxide, water Inorganic fillers such as aluminum oxide, glass beads, silicon nitride, barium sulfate, gypsum, calcium silicate, sericite activated clay, aluminum nitride, polyester fine particles, polyurethane fine particles, vinyl polymer fine particles, acrylic polymer fine particles, core shell acrylate Examples thereof include organic fillers such as polymer fine particles. These fillers may be used alone or in combination of two or more.

The content of the filler is preferably 5% by weight and preferably 70% by weight with respect to the whole sealing agent for liquid crystal dropping method. When the content of the filler is less than 5% by weight, effects such as improvement in adhesiveness may not be sufficiently exhibited. When content of the said filler exceeds 70 weight%, the viscosity of the sealing compound for liquid crystal dropping methods obtained will become high, and applicability | paintability may worsen. A more preferable lower limit of the content of the filler is 10% by weight, and a more preferable upper limit is 50% by weight.

It is preferable that the sealing compound for liquid crystal dropping method of this invention 1 contains 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 said silane coupling agent, since it is excellent in the effect which improves adhesiveness with a board | substrate etc. and it can suppress the outflow of curable resin in a liquid crystal by chemically bonding with curable resin, it is N, for example. -Phenyl-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-isocyanatopropyltrimethoxysilane, etc. are preferably used. . These silane coupling agents may be used alone or in combination of two or more.

The content of the silane coupling agent is such that the preferred lower limit is 0.1% by weight and the preferred upper limit is 20% by weight with respect to the entire liquid crystal dropping method sealing agent. If the content of the silane coupling agent is less than 0.1% by weight, the effect of blending the silane coupling agent may not be sufficiently exhibited. When content of the said silane coupling agent exceeds 20 weight%, the sealing compound for liquid crystal dropping methods obtained may contaminate a liquid crystal. The more preferable lower limit of the content of the silane coupling agent is 0.5% by weight, and the more preferable upper limit is 10% by weight.

In addition to the light-shielding flexible particles, the sealing agent for liquid crystal dropping method of the present invention 1 may further contain a light-shielding agent that is not contained in the flexible particles. As the light-shielding agent, the same light-shielding agent as that contained in the soft particles described above can be used.

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

The sealing agent for the liquid crystal dropping method of the present invention 1 further includes a reactive diluent for adjusting the viscosity, a spacer such as polymer beads for adjusting the panel gap, an antifoaming agent, a leveling agent, and a polymerization prohibition, if necessary. An additive such as an agent and other coupling agents may be contained.

The method for producing the sealing agent for the liquid crystal dropping method of the present invention 1 is not particularly limited. For example, it is curable using a mixer such as a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, or a three roll. Examples thereof include a method of mixing a resin, a polymerization initiator and / or a thermosetting agent, light-shielding flexible particles, and an additive such as a silane coupling agent added as necessary.

In the sealing agent for liquid crystal dropping method of the present invention 1, the preferred lower limit of the viscosity measured at 25 ° C. and 1 rpm using an E-type viscometer is 50,000 Pa · s, and the preferred upper limit is 500,000 Pa · s. When the viscosity is less than 50,000 Pa · s or exceeds 500,000 Pa · s, workability when applying the liquid crystal dropping method sealing agent to a substrate or the like may be deteriorated. A more preferable upper limit of the viscosity is 400,000 Pa · s.

The sealing agent for liquid crystal dropping method of the present invention 1 preferably has an OD value of 2 or more, more preferably 3 or more. The higher the light-shielding property of the sealing agent for liquid crystal dropping method of the present invention 1, the better. The OD value of the sealing agent for liquid crystal dropping method of the present invention 1 is not particularly preferred, but it is usually 6 or less.

A vertical conduction material can be manufactured by mix | blending electroconductive fine particles with the sealing compound for liquid crystal dropping methods of this invention 1. FIG. Such a vertical conduction material containing the sealing agent for liquid crystal dropping method of the present invention 1 and conductive fine particles is also one aspect of the present invention.

As said electroconductive fine particles, what formed the conductive metal layer on the surface of a metal ball, resin microparticles | fine-particles etc. can be used, for example. Among them, the one in which the conductive metal layer is formed on the surface of the resin fine particles is preferable because the conductive connection is possible without damaging the transparent substrate due to the excellent elasticity of the resin fine particles.

The liquid crystal display element using the sealing agent for liquid crystal dropping method of the present invention 1 or the vertical conduction material of the present invention is also one aspect of the present invention.

As a method for producing the liquid crystal display element of the present invention, for example, two transparent substrates such as a glass substrate with electrodes such as an ITO thin film and a polyethylene terephthalate substrate are prepared, and one of them is a seal for the liquid crystal dropping method of the present invention 1 The step of forming a rectangular seal pattern by screen printing, dispenser application, etc., the liquid crystal dropping method sealing agent of the present invention 1 is dropped on the entire surface of the transparent substrate with the liquid crystal drop method uncured Examples of the method include a step of applying and immediately superimposing the other substrate, and a step of heating and curing the sealing agent for liquid crystal dropping method of the first aspect of the present invention. Moreover, you may perform the process of irradiating light, such as an ultraviolet-ray, to a seal pattern part, and preliminarily hardening a sealing agent before the process of heating and hardening the sealing compound for liquid crystal dropping methods of this invention 1.

Next, the present invention 2 will be described in detail.
The light-shielding flexible silicone particle of the present invention 2 comprises a silicone-based particle containing a light-shielding agent. The light-shielding flexible silicone particles of the present invention 2 can be suitably used as the light-shielding flexible particles contained in the sealing agent for liquid crystal dropping method of the present invention 1. That is, the present inventor blends the light-shielding flexible silicone particles into the sealing agent, so that when the substrate of the liquid crystal display element is bonded, the light-shielding flexible silicone particles are mixed with other sealing agent components and liquid crystals. It has been found that the sealing agent can be prevented from eluting into the liquid crystal, and light leakage of the liquid crystal display element can be prevented, and the present invention 2 has been completed.

Examples of the method of adding a light-shielding agent to the silicone-based particles include, for example, by dispersing a colorant such as a pigment or a dye as the light-shielding agent in the silicone particle raw material at the production stage of the silicone-based particles. A method of containing a colorant in the system particles, a method of coating the surface of the silicone particles with a colorant after producing silicone particles that do not have light shielding properties, and a method of preparing silicone particles that do not have light shielding properties For example, a method of causing the silicone-based particles to absorb a colorant is used.

The silicone-based particles are preferably a silicone cured product having a diorganosiloxane unit represented by the following formula (1) as a repeating unit and having rubber elasticity.

In the formula (1), R ¹ represents an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, an aryl group such as a phenyl group or a tolyl group, an alkenyl group such as a vinyl group or an allyl group, β -Aralkyl groups such as phenylethyl group and β-phenylpropyl group, hydrocarbon groups in which some or all of hydrogen atoms of these hydrocarbon groups are substituted with halogen atoms such as chlorine and fluorine, epoxy groups, amino groups Reactive group-containing organic groups such as a mercapto group, an acryloxy group, and a methacryloxy group. a is preferably from 5 to 5000, and more preferably from 10 to 1000.

The curing mechanism of the silicone particles includes a condensation reaction between a methoxysilyl group (≡SiOCH ₃ ) and a hydroxysilyl group (≡SiOH), a mercaptosilyl group (≡SiSH) and a vinylsilyl group (≡SiCH═CH ₂ ) Radical reaction or addition reaction of vinylsilyl group (≡SiCH═CH ₂ ) and ≡SiH group, etc., but from the point of reactivity and reaction process, it is based on (hydrosilylation) addition reaction It is preferable. That is, in the present invention, it is preferable to use a composition in which (a) a vinyl group-containing organopolysiloxane and (b) an organohydrogenpolysiloxane are subjected to an addition reaction in the presence of (c) a platinum-based catalyst.
Specific examples of such component (a) include compounds represented by the following formula (2).

In formula (2), R ¹ is the same as R ¹ in the formula (1) is preferably one having no aliphatic unsaturated bond. b and c are 0, 1, 2 or 3, and b + c = 3, d is a positive number, e is 0 or a positive number, and 2b + e ≧ 2.

Examples of the organohydrogenpolysiloxane of the component (b) include compounds represented by the following formula (3).

In the above formula (3), R ² is an unsubstituted or substituted monovalent hydrocarbon group bonded to a silicon atom having usually 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms, excluding an aliphatic unsaturated bond. As the unsubstituted or substituted monovalent hydrocarbon group in R ² , for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group Alkyl groups such as hexyl group, cyclohexyl group, octyl group, nonyl group, decyl group, aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group, benzyl group, phenylethyl group, phenylpropyl group, etc. Aralkyl groups of these groups, or those in which some or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine, bromine, chlorine, etc., such as chloromethyl groups, chloropro Group, bromoethyl group, trifluoropropyl group and the like. The unsubstituted or substituted monovalent hydrocarbon group for R ² is preferably an alkyl group or an aryl group, and more preferably a methyl group or a phenyl group. F is 0.7 to 2.1, g is 0.001 to 1.0, and f + g is a positive number satisfying 0.8 to 3.0. Preferably, f is 1.0. -2.0, g is 0.01-1.0, and f + g is 1.5-2.5.
Specific examples of such component (b) include compounds represented by the following formula (4).

In Formula (4), R ¹ is the same as R ¹ in the formula (1) is preferably one having no aliphatic unsaturated bond. m is 0 or 1, n is 2 or 3, and m + n = 3, p is 0 or a positive number, q is 0 or a positive number, and 2m + q ≧ 2.

The component (c) platinum-based catalyst is a catalyst that causes an addition reaction between a vinyl group bonded to a silicon atom in the component (a) and a hydrogen atom (SiH group) bonded to a silicon atom in the component (b). Yes, for example, platinum-supported carbon or silica, chloroplatinic acid, platinum-olefin complex, platinum-alcohol complex, platinum-phosphorus complex, platinum coordination compound and the like.

As a method for producing the silicone-based particles using the components (a) to (c), the component (a) and the component (b) may be reacted in the presence of the component (c) and cured. Although not limited, For example, the method of hardening (a) component and (b) component in high temperature spray drying, the method of hardening in an organic solvent, the method of hardening after making this into an emulsion, etc. are mentioned. Further, in order to further improve the dispersibility of the silicone particles, the surface of the silicone particles may be coated with a polyorganosilsesquioxane resin as necessary.

As described above, the light-shielding flexible silicone particles are obtained by dispersing a colorant such as a pigment or a dye as the light-shielding agent in the raw material of the silicone-based particles, thereby including a colorant in the silicone-based particles. Can be produced. Specifically, a colorant such as a pigment or a dye is previously dispersed or dissolved in the components (a) to (c), and then a curing reaction is performed, whereby silicone-based particles having light shielding properties can be obtained. When the colorant is dispersed in the components (a) to (c), it is preferable to add a surfactant or a dispersant having an affinity for both the silicone component and the colorant. By applying a colorant as a light-shielding agent before the curing reaction, the colorant is less likely to elute or peel off from the particles, and liquid crystal contamination can be suppressed.

In addition, as described above, the light-shielding flexible silicone particles include a method in which a silicone-based particle having no light-shielding property is prepared and then a surface of the silicone-based particle is coated with a colorant, or a silicone having no light-shielding property. It can also be produced by a method in which a colorant is absorbed by the silicone-based particles after the particles are produced. Specifically, the light-shielding property is imparted by dispersing the silicone-based particles having no light-shielding property in a medium in which the colorant is dissolved and stirring for a predetermined time to fix the colorant to the silicone-based particles. Further, light shielding properties can be imparted by fixing a colorant on the surface of the silicone-based particles having no light shielding properties using a compounding device such as a hybridizer or a theta composer.
Further, a method of adsorbing a polymerizable colorant on the surface of the silicone-based particles that do not have light shielding properties may be used. That is, light-shielding properties can be imparted by precipitating a polymer having a skeleton or a functional group that absorbs light of a specific wavelength on the surface of silicone-based particles that do not have light-shielding properties. Specifically, in the presence of silicone particles that do not have light-shielding properties, the polymer as a raw material for the polymer is subjected to emulsion polymerization, soap-free polymerization, dispersion polymerization, or the like, thereby forming the polymer on the surface of the silicone-based particles. Can be deposited.
Examples of the polymer deposited on the surface of the silicone particles include polymers obtained by polymerizing acetylene and derivatives thereof, aniline and derivatives thereof, furan and derivatives thereof, pyrrole and derivatives thereof, thiophene and derivatives thereof, and the like. Especially, the polypyrrole which is excellent in black expression property is preferable.

Commercially available silicone particles can also be used as the silicone particles having no light-shielding property.
Examples of the commercially available silicone particles include KMP-594, KMP-597, KMP-598, KMP-600, KMP-601, KMP-602 (manufactured by Shin-Etsu Silicone), Trefil E-506S, EP- 9215 (manufactured by Toray Dow Corning Co., Ltd.), etc., can be classified and used. The said silicone type particle | grains which do not have light-shielding property may be used independently, and 2 or more types may be used together.

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

The titanium black is a substance having a higher transmittance in the vicinity of the ultraviolet region, particularly for light with a wavelength of 370 to 450 nm, compared to the average transmittance for light with a wavelength of 300 to 800 nm. That is, the above-mentioned titanium black is a light-shielding agent having a property of providing light-shielding properties to the light-shielding flexible silicone particles by sufficiently shielding light having a wavelength in the visible light region, while transmitting light having a wavelength in the vicinity of the ultraviolet region. is there. Therefore, for example, as a polymerization initiator used for a sealing agent for a liquid crystal dropping method, by using a material capable of initiating a reaction with light having a wavelength (370 to 450 nm) at which the transmittance of the titanium black is increased, The photocurability of the liquid crystal dropping method sealing agent can be further increased. On the other hand, when used for a sealing agent for a liquid crystal dropping method or the like, the light shielding agent contained in the silicone particles is preferably a highly insulating material, and titanium black is also suitable as the highly insulating light shielding agent. .
The titanium black preferably has an optical density (OD value) per μm of 3 or more, more preferably 4 or more. The higher the light-shielding property of the titanium black, the better. The OD value of the titanium black is not particularly limited, but is usually 5 or less.

The above-mentioned titanium black exhibits a sufficient effect even if it is not surface-treated, but the surface is treated with an organic component such as a coupling agent, silicon oxide, titanium oxide, germanium oxide, aluminum oxide, oxidized Surface-treated titanium black such as those coated with an inorganic component such as zirconium or magnesium oxide can also be used. Especially, what is processed with the organic component is preferable at the point which can improve insulation more.
Further, when light-shielding flexible silicone particles containing titanium black as a light-shielding agent in the silicone-based particles are used, for example, in a liquid crystal dropping method sealing agent, the liquid crystal dropping method sealing agent has a sufficient light-shielding property. The obtained liquid crystal display element has high contrast without leaking light, and has excellent image display quality.

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

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

The preferable lower limit of the primary particle diameter of the light shielding agent contained in the silicone-based particles is 50 nm, and the preferable upper limit is 500 nm. When the primary particle diameter of the light-shielding agent contained in the silicone-based particles is less than 50 nm, secondary aggregation may be intense and dispersibility in the silicone particles may be significantly reduced. When the primary particle diameter of the light-shielding agent contained in the silicone-based particles exceeds 500 nm, the silicone particles may be hard and easily broken. The more preferable lower limit of the primary particle diameter of the light shielding agent contained in the silicone-based particles is 70 nm, and the more preferable upper limit is 300 nm.

The preferable lower limit of the content of the light-shielding agent contained in the silicone-based particles is 2% by weight and the preferable upper limit is 30% by weight with respect to the entire light-shielding flexible silicone particles. If the content of the light shielding agent contained in the silicone-based particles is less than 2% by weight, sufficient light shielding properties may not be obtained. When the content of the light-shielding agent contained in the silicone-based particles exceeds 30% by weight, the silicone particles may be hard and easily cracked. The more preferable lower limit of the content of the light shielding agent contained in the silicone-based particles is 5% by weight, and the more preferable upper limit is 20% by weight.

When the light-shielding flexible silicone-based particles are used in a sealing agent for a liquid crystal dropping method, the maximum particle size is preferably 100% or more of the cell gap of the liquid crystal display element. If the maximum particle size of the light-shielding flexible silicone-based particles is less than 100% of the cell gap of the liquid crystal display element, seal breakage and liquid crystal contamination may not be sufficiently suppressed. The maximum particle diameter of the light-shielding flexible silicone-based particles is 100% or more of the cell gap of the liquid crystal display element, and more preferably 5 μm or more.
Moreover, the preferable upper limit of the maximum particle diameter of the said light-shielding flexible silicone type particle | grain is 20 micrometers. When the maximum particle diameter of the light-shielding flexible silicone-based particles exceeds 20 μm, when used in a sealing agent for liquid crystal dropping method, a springback occurs, and the obtained sealing agent for liquid crystal dropping method may have poor adhesion. In some cases, a gap defect may occur in the obtained liquid crystal display element. A more preferable upper limit of the maximum particle diameter of the light-shielding flexible silicone-based particles is 15 μm.
Further, the maximum particle size of the light-shielding flexible silicone-based particles is preferably 2.6 times or less of the cell gap. When the maximum particle diameter of the light-shielding flexible silicone-based particles exceeds 2.6 times the cell gap, a spring back is caused when used as a sealing agent for liquid crystal dropping method, and the resulting sealing agent for liquid crystal dropping method is adhesive. Or a gap defect may occur in the obtained liquid crystal display element. A more preferable upper limit of the maximum particle diameter of the light-shielding flexible silicone-based particles is 2.2 times the cell gap, and a more preferable upper limit is 1.7 times the cell gap.
In the present specification, the maximum particle size of the light-shielding flexible silicone-based particles and the average particle size described later are measured using a laser diffraction particle size distribution measuring device for the particles before blending with the sealant. Means the value obtained. As the laser diffraction type distribution measuring device, Mastersizer 2000 (manufactured by Malvern) or the like can be used. Moreover, since the cell gap of a liquid crystal display element changes with display elements, it is not limited, The cell gap of a general liquid crystal display element is 2 micrometers-10 micrometers.

The content ratio of particles having a particle diameter of 5 μm or more in the particle size distribution of the light-shielding flexible silicone particles measured by the laser diffraction type distribution measuring apparatus is 60% or more by volume frequency. It is preferable that When the content ratio of particles having a particle diameter of 5 μm or more is less than 60% by volume frequency, seal breakage or liquid crystal contamination may not be sufficiently suppressed when used as a sealing agent for liquid crystal dropping method. . The content ratio of particles having a particle diameter of 5 μm or more is more preferably 80% or more.

The light-shielding flexible silicone-based particle is a particle having a cell gap of 100% or more of a liquid crystal display element from the viewpoint of more effectively suppressing the occurrence of seal breakage or liquid crystal contamination when used as a sealing agent for a liquid crystal dropping method. Is preferably contained in an amount of 70% or more of the particle size distribution in the whole light-shielding flexible silicone-based particle, and more preferably composed only of particles of 100% or more of the cell gap of the liquid crystal display element.

The preferable lower limit of the average particle diameter of the light-shielding flexible silicone-based particles is 2 μm, and the preferable upper limit is 50 μm. When the average particle diameter of the light-shielding flexible silicone-based particles is less than 2 μm, elution of the sealing agent into the liquid crystal may not be sufficiently prevented when used as a sealing agent for a liquid crystal dropping method. When the average particle diameter of the light-shielding flexible silicone-based particles exceeds 50 μm, the resulting liquid crystal dropping method sealant is inferior in adhesiveness when used in a liquid crystal dropping method sealant, or the liquid crystal obtained A gap defect may occur in the display element. The more preferable lower limit of the average particle diameter of the light-shielding flexible silicone-based particles is 4 μm, the more preferable upper limit is 15 μm, and the still more preferable upper limit is 12 μm.

As the light-shielding flexible silicone-based particles, two or more types of light-shielding flexible silicone-based particles having different maximum particle diameters may be mixed and used. That is, when used for a sealing agent for a liquid crystal dropping method, the light-shielding flexible silicone-based particles having a maximum particle diameter of less than 100% of the cell gap of the liquid crystal display element and the maximum particle diameter of 100% or more of the cell gap of the liquid crystal display element. You may mix and use light-shielding flexible silicone type particle | grains.

The coefficient of variation (hereinafter also referred to as “CV value”) of the light-shielding flexible silicone-based particles is preferably 30% or less. When the CV value of the particle size of the light-shielding flexible silicone-based particles exceeds 30%, a cell gap defect may be caused when used for a sealing agent for liquid crystal dropping method. The CV value of the particle diameter of the light-shielding flexible silicone-based particles is more preferably 28% or less.
In the present specification, the CV value of the particle diameter is a numerical value obtained by the following formula.
CV value of particle diameter (%) = (standard deviation of particle diameter / average particle diameter) × 100

Even if the light-shielding flexible silicone-based particles are those having a maximum particle diameter, an average particle diameter, or a CV value outside the above-described ranges, the maximum particle diameter, the average particle diameter, or the CV value is within the above-described range by classification. Can be inside. In addition, when used in a sealing agent for liquid crystal dropping method, the light-shielding flexible silicone particles having a particle diameter of less than 100% of the cell gap of the liquid crystal display element do not contribute to the suppression of the occurrence of seal breaks and liquid crystal contamination. When mixed with an agent, the thixo value may be increased, so that it is preferably removed by classification.
Examples of the method for classifying the light-shielding flexible silicone-based particles include methods such as wet classification and dry classification. Of these, wet classification is preferable, and wet sieving classification is more preferable.

The light-shielding flexible silicone-based particles have a compression displacement from the origin load value when applying a load to the inversion load value as L1, and from the inversion load value when releasing the load to the origin load value. When the unloading displacement is L2, it is preferable that the recovery rate expressed as a percentage of L2 / L1 is 80% or less. If the recovery rate of the light-shielding flexible silicone-based particles exceeds 80%, the function of preventing the sealing agent from eluting into the liquid crystal may be reduced when used as a sealing agent for a liquid crystal dropping method. . A more preferable upper limit of the recovery rate of the light-shielding flexible silicone-based particles is 70%, and a more preferable upper limit is 60%.
The recovery rate of the light-shielding flexible silicone-based particles is derived by applying a constant load (1 g) to each particle using a micro compression tester and analyzing the recovery behavior after removing the load. be able to.

The light-shielding flexible silicone-based particles preferably have a 1 g strain of 30% or more when L3 / Dn is expressed as a percentage when the compression displacement when a load of 1 g is applied is L3 and the particle diameter is Dn. . If the 1 g strain of the light-shielding flexible silicone-based particles is less than 30%, the function of preventing the sealing agent from eluting into the liquid crystal may be reduced when used as a sealing agent for the liquid crystal dropping method. is there. A more preferable lower limit of 1 g strain of the light-shielding flexible silicone-based particles is 40%.
In addition, 1g distortion of the said light-shielding flexible silicone type particle | grain can be measured by applying 1g to one particle | grain using a micro compression tester, and measuring the displacement amount at that time.

The light-shielding flexible silicone-based particles preferably have a fracture strain expressed as a percentage of L4 / Dn of 50% or more when the compression displacement at the time when the particles are broken is L4 and the particle diameter is Dn. When the fracture strain of the light-shielding flexible silicone-based particles is less than 50%, the function of preventing the sealing agent from eluting into the liquid crystal may be reduced when used as a sealing agent for a liquid crystal dropping method. is there. A more preferable lower limit of the fracture strain of the light-shielding flexible silicone-based particle is 60%.
The breaking strain of the light-shielding flexible silicone-based particles can be measured by applying a load to each particle using a micro compression tester and measuring the amount of 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 said light-shielding flexible silicone type particle | grains are -200 degreeC with a preferable minimum of glass transition temperature, and a preferable upper limit is 40 degreeC. If the glass transition temperature of the light-shielding flexible silicone particles is −200 ° C. or higher, the lower the better the effect of suppressing seal break and liquid crystal contamination, but if it is lower than −200 ° C., there is a problem in particle handling. In some cases, the sealing agent is easily crushed during heating, and the sealing agent in the middle of curing comes into contact with the liquid crystal to cause liquid crystal contamination. When the glass transition temperature of the light-shielding flexible silicone particles exceeds 40 ° C., a gap defect may occur. The minimum with a more preferable glass transition temperature of the said light-shielding flexible particle | grain is -150 degreeC, and a more preferable upper limit is 35 degreeC. In addition, the glass transition temperature of the said light-shielding flexible silicone type particle | grain shows the value measured by the differential scanning calorimetry (DSC) based on "The transition temperature measuring method of plastics" of JISK7121.

ADVANTAGE OF THE INVENTION According to this invention, the sealing agent for liquid crystal dropping methods which is excellent in adhesiveness, hardly causes liquid crystal contamination, and can prevent the light leakage of a liquid crystal display element can be provided. Moreover, according to this invention, the vertical conduction material and liquid crystal display element which are manufactured using this sealing compound for liquid crystal dropping methods can be provided. Furthermore, according to the present invention, light-shielding flexible silicone particles 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.

(Preparation of light-shielding flexible particles A)
500 g of methyl vinyl siloxane having a viscosity of 600 cP (compound represented by the following formula (5)), 20 g of methyl hydrogen polysiloxane having a viscosity of 30 cP (compound represented by the following formula (6)), and titanium black (Mitsubishi Materials Corporation) 26 g of “13M”) was charged into a 1 liter glass beaker and stirred and mixed at 2000 rpm using a homomixer.
Next, 1 g of polyoxyethylene (added mole number = 9 mol) octylphenyl ether and 150 g of water were added and stirring was continued at 6000 rpm. Phase inversion occurred and thickening was observed, but stirring was further continued at 3000 rpm. When 329 g of water was added while performing, an O / W type emulsion was obtained.

Next, this emulsion was transferred to a glass flask equipped with a stirrer with a vertical stirring blade, and 1 g of a toluene solution of a chloroplatinic acid-olefin complex (platinum content 0.05%) and a polysiloxane were stirred at room temperature (25 ° C.). When a mixture with 1 g of oxyethylene (added mole number = 9 mol) octylphenyl ether was added and reacted for 12 hours, a dispersion (hereinafter also referred to as “silicone rubber spherical fine particle aqueous dispersion-1”) was obtained. However, when the average particle size of the particles in the dispersion was measured using a Coulter Counter (manufactured by Coulter Electronics Co., Ltd.), it was 10 μm. When several g of this dispersion was dried at room temperature, an elastic rubber was obtained. A powder was obtained.

A 3 liter glass flask is charged with 2290 g of water, 580 g of silicone rubber spherical fine particle aqueous dispersion-1 and 60 g of ammonia water (concentration 28 wt%), water temperature is 10 ° C., and the blade temperature is 200 rpm. Stirring was performed with a mold stirring blade. The pH of the liquid at this time was 11.2, but 65 g of methyltrimethoxysilane was dropped into this liquid over 20 minutes, and the liquid temperature was kept at 5 to 15 ° C. during this time, and stirring was further performed for 4 hours. The mixture was heated to 55 to 60 ° C. and then stirred for 1 hour, and the resulting liquid was made into a cake with about 30% water using a pressure filter.

Next, the cake was dried in a hot air circulating dryer at a temperature of 105 ° C., and the resulting dried product was crushed by a jet mill. Then, the predetermined particle diameter and the maximum particle diameter were adjusted by classification operation, and light-shielding flexible particles A, which are light-shielding flexible silicone particles containing a light-shielding agent, were obtained.

500 g of methyl vinyl siloxane having a viscosity of 600 cP (compound represented by the following formula (5)), 20 g of methyl hydrogen polysiloxane having a viscosity of 30 cP (compound represented by the following formula (6)), and titanium black (Mitsubishi Materials Corporation) Made in a 13 liter glass beaker and stirred and mixed at 2000 rpm using a homomixer, a toluene solution of chloroplatinic acid-olefin complex (platinum content 0) was prepared. .05%) to prepare a mixed solution to which 1 g was added.
The obtained mixed liquid is poured onto a bat that has been previously coated with Teflon (registered trademark), the height is adjusted so that the thickness after curing is 1 mm, and the sheet is reacted at room temperature for 24 hours. Obtained. The obtained sheet was cut to obtain a flaky blackness measuring sample having a thickness of 1 mm and the same composition as the light-shielding flexible particles A.
The black measured by using “maximum particle diameter”, “average particle diameter”, “CV value of particle diameter”, “glass transition temperature”, UV-3600 (manufactured by Shimadzu Corporation) of the obtained light-shielding flexible particles A Using a “blackening degree” of the sample for measuring the degree of conversion and a micro compression tester (manufactured by Shimadzu Corporation, “PCT-200”), the compression speed of the fine particles is 0 on a smooth cylindrical end face made of diamond having a diameter of 50 μm Table 1 shows “recovery rate”, “1 g strain”, and “breaking strain” measured under the conditions of .28 mN / sec, origin load value 1.0 mN, and reverse load value 10 mN.

(Preparation of light-shielding flexible particles B)
Except that the amount of titanium black (Mitsubishi Materials Co., Ltd., “13M”) used is 52 g, the same reaction as the light-shielding flexible A is carried out, and the light-shielding flexible silicone particles are used as the soft particles containing the light-shielding agent. Samples for measuring the degree of blackening in the form of flakes having a thickness of 1 mm and having the same composition as the light-shielding flexible particles B and the light-shielding flexible particles B were prepared.
The obtained light-shielding flexible particles B were measured in the same manner as the light-shielding flexible particles A, and the “maximum particle diameter”, “average particle diameter”, “CV value of particle diameter”, “glass transition temperature”, “black” Table 1 shows the “degree of conversion”, “recovery rate”, “1 g strain”, and “breaking strain”.

(Preparation of light-shielding flexible particles C)
Using only methyl vinyl siloxane and methyl hydrogen polysiloxane without adding titanium black, the same reaction as in “Preparation of light-shielding flexible particles A” was performed to obtain silicone-based particles.
20 g of the obtained silicone particles and 210 g of water were charged into a 1 liter separable flask and stirred and dispersed. Separately, a solution in which 3 g of polyvinylpyrrolidone was dissolved in 50 g of water was prepared, added to the above separable flask, and stirred for 30 minutes.
Subsequently, 10 g of pyrrole, 5.3 g of peroxygenated water (15 wt%) and 24.4 g of sulfuric acid (5 wt%) were added and stirred for 30 minutes. Thereafter, 0.08 g of iron sulfate heptahydrate was dissolved in 1 g of water and added to the separable flask. Thereafter, stirring was continued at room temperature for 12 hours, and then the particles were washed several times with water. After the dispersion was dried at room temperature, the predetermined particle diameter and the maximum particle diameter were adjusted by classification operation, and light-shielding flexible particles C that were light-shielding flexible silicone particles were obtained.
The obtained light-shielding flexible particles C were measured in the same manner as the light-shielding flexible particles A, and “maximum particle diameter”, “average particle diameter”, “CV value of particle diameter”, “glass transition temperature”, “recovery”. Table 1 shows the “rate”, “1 g strain”, and “breaking strain”.
In addition, about the light-shielding flexible particle C, since the sample for blackening degree measurement was not able to be produced, the blackening degree was not measured.

(Preparation of light-shielding flexible particles D)
50 g of polytetramethylene glycol diacrylate, 950 g of ethylhexyl methacrylate, and 50 g of titanium black (“13M” manufactured by Mitsubishi Materials Corporation) were charged into a 3 liter glass beaker and stirred and mixed at 2000 rpm using a homomixer. Furthermore, 40 g of benzoyl peroxide was added to this mixed solution and mixed with a stirring blade until it was uniformly dissolved (hereinafter, the obtained mixed solution is also referred to as “monomer mixed solution”).
The monomer mixture is put into a reaction kettle charged with 5 kg of a 1% by weight aqueous solution of polyvinyl alcohol and stirred for 2 to 4 hours to adjust the particle size so that the monomer droplets have a predetermined particle size. It was. Thereafter, the reaction was performed in a nitrogen atmosphere at 85 ° C. for 9 hours to obtain polymer particles. After the obtained polymer particles were washed several times with hot water, classification operation was performed to adjust the particle size and the maximum particle size. Further, after solvent substitution with methanol several times, the mixture was dried for 12 hours at 30 ° C. under reduced pressure in a vacuum dryer to obtain light-shielding flexible particles D.
By pouring a part of the monomer mixture onto a vat that has been pre-coated with Teflon (registered trademark), adjusting the height so that the thickness after curing is 1 mm, and reacting at 85 ° C. for 20 hours , Got a sheet. The obtained sheet was cut to obtain a flaky blackness measuring sample having a thickness of 1 mm and the same composition as the light-shielding flexible particles D.
The obtained light-shielding flexible particles D were measured in the same manner as the light-shielding flexible particles A, and the “maximum particle diameter”, “average particle diameter”, “CV value of particle diameter”, “glass transition temperature”, “black” Table 1 shows the “degree of conversion”, “recovery rate”, “1 g strain”, and “breaking strain”.

(Preparation of light-shielding flexible particles E)
The same operation as that for the light-shielding flexible particles D was performed except that 400 g of polytetramethylene glycol diacrylate and 600 g of styrene were used in place of 50 g of polytetramethylene glycol diacrylate and 950 g of ethylhexyl methacrylate. Samples for measuring the degree of blackening in the form of flakes having a thickness of 1 mm and having the same composition as the flexible particles E and the light-shielding flexible particles E were prepared.
The obtained light-shielding flexible particles E were measured in the same manner as the light-shielding flexible particles A, and “maximum particle diameter”, “average particle diameter”, “CV value of particle diameter”, “glass transition temperature”, “black” Table 1 shows the “degree of conversion”, “recovery rate”, “1 g strain”, and “breaking strain”.

(Preparation of light-shielding flexible particles F)
The same operation as that for the light-shielding flexible particles D was performed except that 750 g of polytetramethylene glycol diacrylate and 250 g of styrene were used instead of 50 g of polytetramethylene glycol diacrylate and 950 g of ethylhexyl methacrylate. A sample for measuring the degree of blackening having a thickness of 1 mm and having the same composition as the flexible particles F and the light-shielding flexible particles F was prepared.
The obtained light-shielding flexible particles F were measured in the same manner as the light-shielding flexible particles A, and the “maximum particle diameter”, “average particle diameter”, “CV value of particle diameter”, “glass transition temperature”, “black” Table 1 shows the “degree of conversion”, “recovery rate”, “1 g strain”, and “breaking strain”.

(Preparation of light-shielding flexible particles G)
The light-shielding flexible particles G were obtained in the same manner as the light-shielding flexible particles A except that the maximum particle size was adjusted to 5 μm or less during classification.
The obtained light-shielding flexible particles F were measured in the same manner as the light-shielding flexible particles A, and the “maximum particle diameter”, “average particle diameter”, “CV value of particle diameter”, “glass transition temperature”, “black” Table 1 shows the “degree of conversion”, “recovery rate”, “1 g strain”, and “breaking strain”.
Since the particle composition is the same as that of the light-shielding flexible particles A, the same sample as that obtained for the light-shielding flexible particles A was used as the sample for measuring the degree of blackening.

(Preparation of non-light-shielding flexible particles A)
Except that titanium black was not added, the same reaction as that of the light-shielding flexible particle A was performed, and the same composition as the non-light-shielding flexible particle A and the non-light-shielding flexible particle A was obtained as a soft particle containing no light-shielding agent. A 1 mm thick flaky sample for measuring the degree of blackening was prepared.
The obtained non-light-shielding flexible particles A were measured in the same manner as the light-shielding flexible particles A, and the “maximum particle diameter”, “average particle diameter”, “CV value of particle diameter”, “glass transition temperature”, “ Table 1 shows the degree of blackening, “recovery rate”, “1 g strain”, and “breaking strain”.

Example 1
70 parts by weight of bisphenol A type epoxy acrylate (manufactured by Daicel Ornex Co., Ltd., “Evekril 3700”) and 30 parts by weight of bisphenol F type epoxy resin (manufactured by Mitsubishi Chemical Corporation, “jER806”) as a curable resin, and a thermal radical polymerization initiator 7 parts by weight of a polymer azo initiator (“VPE-0201” manufactured by Wako Pure Chemical Industries, Ltd.) and 8 parts by weight of sebacic acid dihydrazide (“SDH” manufactured by Otsuka Chemical Co., Ltd.) as a thermosetting agent 30 parts by weight of particles A, 10 parts by weight of silica (manufactured by Admatechs, “Admafine SO-C2”) as filler, and 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Silicone, “ KBM-403 ") 1 part by weight and mixed with a planetary stirrer (Shinky Corp.," Awatori Nertaro ") After stirring, to obtain a liquid crystal dropping process sealant uniformly mixed with the ceramic three roll.

(Examples 2-14, Comparative Examples 1-3)
According to the blending ratio described in Table 2, each material was mixed using a planetary stirrer (“Shinky Netaro” manufactured by Shinky Corporation) in the same manner as in Example 1, and then further three rolls were used. The liquid crystal dropping method sealing agents of Examples 2 to 14 and Comparative Examples 1 to 3 were prepared.

<Evaluation>
The following evaluation was performed about each sealing compound for liquid crystal dropping methods obtained by the Example and the comparative example. The results are shown in Table 2.

(Adhesiveness)
1 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 liquid crystal dropping method sealing agent obtained in Examples and Comparative Examples. Disperse evenly with a mechanical stirrer, take a trace amount in the center of Corning glass 1737 (20 mm x 50 mm x thickness 0.7 mm), overlay the same type of glass on top of it, and press the liquid crystal dropping method sealant The adhesive was spread and heated at 120 ° C. for 1 hour to thermally cure the sealant 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 270 N / cm ² or more was “◯”, the case where the adhesive strength was 250 N / cm ² or more and less than 270 N / cm ² was “Δ”, and the adhesive strength was less than 250 N / cm ² . The case was evaluated as “x” and the adhesion was evaluated.

(Light shielding)
1 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 liquid crystal dropping method sealing agent obtained in Examples and Comparative Examples. A glass stirrer was uniformly dispersed with a glass stirrer and applied onto a 50 mm × 50 mm glass substrate, and the same type of glass substrate was overlaid thereon. Next, it heated at 120 degreeC for 1 hour, the sealing agent was thermosetted, and the test piece for OD value measurement was obtained. The obtained OD value measurement specimen was measured for the OD value using PDA-100 (manufactured by Konica Corporation), and when the OD value was 3 or more, “◯◯” was 2.5 or more and less than 3. The light-shielding property was evaluated as “◯” when 2 or less and less than 2.5, and “△” when 2 or less and “x” when 2 or less.

(Liquid crystal contamination)
One part by weight of spacer particles (Sekisui Chemical Co., Ltd., “Micropearl SP-2050”) having an average particle diameter of 5 μm is used as a planetary type with respect to 100 parts by weight of each liquid crystal dropping method sealing agent obtained in Examples and Comparative Examples. After uniformly dispersing with a stirrer, the obtained sealing agent is filled into a dispensing syringe (manufactured by Musashi Engineering, "PSY-10E") and defoamed, and then dispenser (manufactured by Musashi Engineering, " The sealant was applied so as to draw a rectangular frame on a transparent electrode substrate with an ITO thin film by using SHOTMASTER 300 ”). Subsequently, fine droplets of TN liquid crystal (manufactured by Chisso Corporation, “JC-5001LA”) were applied dropwise with a liquid crystal dropping device, and the other transparent substrate was bonded under a vacuum of 5 Pa with a vacuum bonding device. . The cell after bonding was heated at 120 ° C. for 1 hour to thermally cure the sealing agent, and a liquid crystal display element (cell gap 5 μm) was obtained.
For the obtained liquid crystal display element, the display unevenness generated in the liquid crystal (especially the corner portion) around the seal portion is visually observed. If there is no display unevenness at all, “○○” indicates that there is almost no display unevenness. The liquid crystal contamination property was evaluated with “◯”, “△” when slight display unevenness occurred, and “X” when severe display unevenness was confirmed.

ADVANTAGE OF THE INVENTION According to this invention, the sealing agent for liquid crystal dropping methods which is excellent in adhesiveness, hardly causes liquid crystal contamination, and can prevent the light leakage of a liquid crystal display element can be provided. Moreover, according to this invention, the vertical conduction material and liquid crystal display element which are manufactured using this sealing compound for liquid crystal dropping methods can be provided. Furthermore, according to the present invention, light-shielding flexible silicone particles can be provided.

Claims (12)

A liquid crystal dropping method sealing agent used for manufacturing a liquid crystal display element by a liquid crystal dropping method,
A sealing agent for liquid crystal dropping method, comprising a curable resin, a polymerization initiator and / or a thermosetting agent, and light-shielding flexible particles. The sealant for a liquid crystal dropping method according to claim 1, wherein the light-shielding flexible particles have a maximum particle size of 100% or more of a cell gap of the liquid crystal display element. The light-shielding flexible particle has a compression displacement from the load value for the origin when the load is applied to the reverse load value as L1, and the unloading displacement from the reverse load value when the load is released to the load value for the origin. 3. The sealing agent for liquid crystal dropping method according to claim 1 or 2, wherein a recovery rate expressed as a percentage of L2 / L1 is 80% or less when L2 is L2. The light-shielding flexible particles are characterized in that, when the compression displacement when a load of 1 g is applied is L3 and the particle diameter is Dn, the 1 g strain expressed as a percentage of L3 / Dn is 30% or more. Item 4. The sealing agent for liquid crystal dropping method according to item 1, 2 or 3. The sealing agent for liquid crystal dropping method according to claim 1, 2, 3, or 4, wherein the light-shielding flexible particles have a glass transition temperature of -200 to 40 ° C. The light-shielding flexible particles are characterized in that the fracture strain when L4 / Dn is expressed as a percentage is 50% or more when the compression displacement at the time when the particles are broken is L4 and the particle diameter is Dn. The sealing agent for liquid crystal dropping method according to 2, 3, 4 or 5. The sealing compound for liquid crystal dropping method according to claim 1, 2, 3, 4, 5 or 6, wherein the light-shielding flexible particles have a coefficient of variation in particle diameter of 30% or less. 8. The sealing agent for a liquid crystal dropping method according to claim 1, further comprising a light shielding agent in addition to the light shielding flexible particles. A vertical conduction material comprising the sealing agent for liquid crystal dropping method according to claim 1, 2, 3, 4, 5, 6, 7 or 8, and conductive fine particles. A liquid crystal display element manufactured using the sealing agent for liquid crystal dropping method according to claim 1, 2, 3, 4, 5, 6, 7 or 8, or the vertical conduction material according to claim 9. A light-shielding flexible silicone particle comprising a silicone-based particle containing a light-shielding agent. 12. The light-shielding flexible silicone particle according to claim 11, wherein the average particle size is 2 to 50 [mu] m.