JP6588825B2 - Liquid crystal dropping method sealing agent, vertical conduction material, and liquid crystal display element - Google Patents

Description

The present invention relates to a sealant for a liquid crystal dropping method capable of satisfying both suppression of seal break and liquid crystal contamination and suppression of gap failure due to springback. 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.

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. A liquid crystal dropping method called a dripping method using such a photothermal combined curing type sealant has become the mainstream.

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.

By the way, in the present age when mobile devices with various liquid crystal panels such as mobile phones and portable game machines are widespread, downsizing of devices is the most demanded issue. As a technique for miniaturization, there is a narrow frame of the liquid crystal display unit, and for example, the position of the seal portion is arranged under the black matrix (hereinafter also referred to as “narrow frame design”).
However, when a liquid crystal display element with a narrow frame design is manufactured by the dropping method, there is a portion where the light does not shine on the seal part due to the black matrix. Since the uncured sealant comes into contact with the liquid crystal, the liquid crystal is inserted into the sealant, a seal break occurs and the liquid crystal leaks out, or the uncured photocurable resin elutes after the temporary curing process. There was a problem that the liquid crystal may be contaminated.

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

An object of the present invention is to provide a sealing agent for a liquid crystal dropping method capable of achieving both suppression of seal break and liquid crystal contamination and suppression of gap failure due to springback. 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.

The present invention is a liquid crystal dropping method sealing agent used in the production of a liquid crystal display element by a liquid crystal dropping method, which contains a curable resin, a polymerization initiator and / or a thermosetting agent, and flexible particles, in the particle size distribution of the particle size modal is Ri der 1.07 or more times the median particle size, the curable resin contains a (meth) acrylic resin, the flexible particles, silicone particles and / Or it is a sealing compound for liquid crystal dropping methods which contains vinyl particle | grains and whose content of the said flexible particle | grain is 15 to 50 weight part with respect to 100 weight part of said curable resins .
The present invention is described in detail below.

The present inventors blended soft particles in a liquid crystal dropping method sealing agent, and caused the soft particles to serve as a barrier between other sealing agent components and liquid crystal, thereby generating seal breakage and liquid crystal contamination. We studied to suppress this.
However, when such flexible particles are blended, a cell gap defect due to springback may occur in the obtained liquid crystal display element.
Therefore, as a result of intensive studies, the present inventors have determined that, by blending soft particles having a mode particle size larger than a specific value by a specific value larger than the median particle size in the particle size distribution, it is possible to suppress seal break and liquid crystal contamination and to perform springback. It has been found that a sealing agent for a liquid crystal dropping method capable of achieving both suppression of gap defects can be obtained, and the present invention has been completed.

The sealant for a liquid crystal dropping method of the present invention is used for manufacturing a liquid crystal display element by a liquid crystal dropping method.
The sealing agent for liquid crystal dropping method of the present invention contains flexible particles.
When the liquid crystal display device is manufactured, the flexible particles serve as a barrier between the other sealing agent component and the liquid crystal, preventing the liquid crystal from being inserted into the sealing agent and the sealing agent from being eluted into the liquid crystal. Have a role to play. Further, by blending the flexible particles, it is possible to prevent the substrate from being displaced until the sealing agent is cured after the substrates are bonded together.

The flexible particles have a mode particle size of 1.07 or more times the median particle size in the particle size distribution. When the mode particle diameter of the flexible particle is 1.07 times or more of the median particle diameter, both the seal break and liquid crystal contamination can be suppressed, and the cell gap defect can be suppressed by springback. In the particle size distribution, the flexible particles preferably have a mode particle size larger than 1.07 times the median particle size, and more preferably larger than 1.10 times.
In the present specification, the mode particle size, the median particle size, the maximum particle size, the minimum particle size, and the average particle size in the flexible particles are measured using a Coulter type particle size distribution measuring device. The value obtained by doing. As the Coulter type distribution measuring apparatus, Multisizer 4 (manufactured by Beckman Coulter, Inc.) or the like can be used. Specifically, 0.1 g of particles are added to 10 g of methanol to be acclimatized, and ultrasonic dispersion is performed for 5 minutes. Prepare the particle dispersion and drop into the beaker containing the electrolyte “ISOTON II” (Beckman Coulter, Inc.) in the sample stand until the displayed concentration of the measuring device reaches 5%. Inject with. By using this concentration, a reproducible measurement value can be obtained. The measurement is performed twice, and the arithmetic average value of the calculated values is used.

The “mode particle size” means a particle size indicating the maximum frequency of the particle size distribution by volume frequency. In the particle size distribution measured using the Coulter type particle size distribution measuring apparatus, a computer system for data processing (Beckman -It can be calculated using a device connected to Coulter). In the measurement apparatus, the aperture pore diameter is 50 μm, the measurement range of 1 to 30 μm is divided into 300, the frequency value is calculated on a volume basis, and the particle diameter indicating the maximum frequency can be calculated.

The “medium particle size” means a particle size when the volume of particles larger than the particle size occupies 50% of the volume of all particles in the particle size distribution by volume frequency. The particle size distribution measured by using the apparatus can be calculated using an apparatus connected to a computer system for data processing (manufactured by Beckman Coulter). In the measurement device, the aperture pore size is 50 μm, the measurement range of 1 to 30 μm is divided into 300, the frequency value is calculated on a volume basis, and the particle diameter of 50% is the medium from the smallest volume integral ratio. The particle diameter can be calculated.

The “maximum particle size” is a particle size distribution measured using the Coulter type particle size distribution measuring device. As the particle size increases from the mode particle size, the volume frequency decreases continuously, and the particles are detected. The particle diameter immediately before being stopped is defined as the maximum particle diameter. Note that particles whose volume frequency is detected discontinuously are highly likely to be aggregated particles, and are therefore excluded from the maximum particle size.

The “minimum particle size” is 1.05 μm, which is the lower limit of detection with a 50 μm aperture used uniformly, regardless of the sample to be measured.

The “average particle size” can be calculated using a device connected to a data processing computer system (manufactured by Beckman Coulter, Inc.) in the particle size distribution measured using the Coulter particle size distribution measuring device. . In the measuring apparatus, the aperture pore diameter is 50 μm, the measurement range of 1 to 30 μm is divided into 300, and the average particle diameter can be calculated on a volume basis.

“D90” to be described later means a particle diameter when the volume of particles larger than the particle diameter occupies 10% of the volume of all particles in the particle size distribution by volume frequency, and the above-mentioned Coulter type particle size distribution measuring apparatus is used. The measured particle size distribution can be calculated using a device connected to a data processing computer system (manufactured by Beckman Coulter). In the measurement apparatus, the aperture pore diameter is 50 μm, the measurement range of 1 to 30 μm is divided into 300, and the particle diameter of 90% can be calculated as D90 from the smaller volume integration rate.

In order to achieve both effective suppression of seal break and liquid crystal contamination and suppression of cell gap failure due to springback, the flexible particle has a D90 in the cumulative distribution of less than 1.40 times the median particle size. It is preferable that it is less than 1.35 times.

The above-mentioned flexible particles have a particle size distribution that is 2 μm smaller than the median particle size from the minimum particle size in terms of particle size distribution from the viewpoint of more effectively achieving both seal break and liquid crystal contamination suppression and suppression of cell gap failure by springback. W / Z ≧ 1.1 where the ratio of volume frequency up to W (%) and the ratio of volume frequency from the particle diameter 2 μm larger than the median particle diameter to the maximum particle diameter is Z (%). It is preferable that W / Z ≧ 1.2.

From the viewpoint of achieving both effective suppression of seal break and liquid crystal contamination and suppression of cell gap failure due to springback, the above-mentioned flexible particles have a medium particle size from 2 μm smaller than the medium particle size in the particle size distribution. X + Y ≧ 60, where X (%) is the volume frequency ratio to the diameter and Y (%) is the volume frequency ratio from the median particle diameter to the particle diameter 2 μm larger than the median particle diameter. Preferably, X + Y ≧ 70 is more preferable.

In terms of particle size distribution, the above-mentioned flexible particles have a maximum particle size from a particle size 2 μm larger than the median particle size, from the viewpoint of more effectively suppressing seal break and liquid crystal contamination and suppressing cell gap failure by springback. Up to the total volume frequency, that is, Z is less than 10% of the total, and the total volume frequency from the smallest particle diameter to a particle diameter 2 μm smaller than the median particle diameter, ie, the W is Preferably it is less than 20%.

Examples of a method for setting the mode particle diameter of the soft particles to 1.07 times or more of the median particle size include, for example, a method of classifying soft particles whose mode particle size is less than 1.07 times the median particle size. And a method of mixing two or more kinds of soft particles having different particle size distributions.

Examples of the method for classifying the flexible particles include wet classification and dry classification. Of these, wet classification is preferable, and wet sieving classification is more preferable.
Specifically, for example, a method in which a slurry in which flexible particles are dispersed in an appropriate dispersion medium is sieved using a high-precision sieve or the like having uniform openings is preferably used.

The flexible particles preferably have a maximum particle size of 100% or more of the cell gap of the liquid crystal display element and 5 to 50 μm. If the maximum particle size of the flexible particles is less than 100% of the cell gap of the liquid crystal display element or less than 5 μm, seal breakage and liquid crystal contamination may not be sufficiently suppressed. If the maximum particle diameter of the flexible particles exceeds 50 μm, spring back may occur, and the resulting liquid crystal dropping method sealant may have poor adhesion, or a gap defect may occur in the resulting liquid crystal display element. is there. A more preferable upper limit of the maximum particle diameter of the flexible particles is 12 μm, and a more preferable upper limit is 15 μm.
The maximum particle size of the flexible particles is preferably 2.6 times or less of the cell gap. When the maximum particle size of the flexible particles exceeds 2.6 times the cell gap, a springback occurs, and the obtained liquid crystal dropping method sealant is inferior in adhesiveness or the obtained liquid crystal display element has a gap defect. May occur. A more preferable upper limit of the maximum particle diameter of the flexible particles is 2.2 times the cell gap, and a more preferable upper limit is 1.7 times the cell gap.
The cell gap of the liquid crystal display element is not limited because it varies depending on the display element, but the cell gap of a general liquid crystal display element is 2 to 10 μm.

In the flexible particles, the content ratio of particles having a particle diameter of 5 μm or more in the particle size distribution of the flexible particles measured by the Coulter type distribution measuring device is preferably 60% or more by volume frequency. 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 flexible particles contain 100% or more of the cell gap of the liquid crystal display element by 70% or more of the particle size distribution in the entire flexible particles from the viewpoint of further exerting the effect of suppressing the occurrence of seal break and liquid crystal contamination. It is preferable that the liquid crystal display element is composed only of particles having a cell gap of 100% or more.

The preferable lower limit of the average particle diameter of the flexible particles is 2 μm, and the preferable upper limit is 15 μm. If the average particle size of the flexible particles is less than 2 μm, the occurrence of seal breaks and liquid crystal contamination may not be sufficiently suppressed. When the average particle diameter of the flexible particles exceeds 15 μm, 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. A more preferable lower limit of the average particle diameter of the flexible particles is 4 μm, a more preferable upper limit is 12 μm, and a further preferable lower limit is 5 μm.

The coefficient of variation (hereinafter also referred to as “CV value”) of the flexible particles is preferably 30% or less. When the CV value of the particle diameter of the flexible particles exceeds 30%, a cell gap defect may be caused. The CV value of the particle diameter of the 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 in the particle size distribution measured using the Coulter particle size distribution measuring apparatus.
CV value of particle diameter (%) = (standard deviation of particle diameter / average particle diameter) × 100

Even if the above-mentioned flexible particles are those whose maximum particle diameter, average particle diameter, and CV value are outside the above-mentioned ranges, the maximum particle diameter, average particle diameter, and CV value are within the above-mentioned ranges by classification by the above-described method. Can be inside. In addition, 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 seal break and liquid crystal contamination, and may increase the thixo value when mixed with a sealant. It is preferable to remove it.

The above-mentioned flexible particles have 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. When L2, L2 / L1 is preferably 80% or less. If the recovery rate of the flexible particles exceeds 80%, the effect of suppressing the occurrence of seal breaks and liquid crystal contamination may not be sufficiently exhibited. A more preferable upper limit of the recovery rate of the flexible particles is 70%, and a more preferable upper limit is 60%.
In addition, the recovery rate of the said soft particle | grain can be derived | led-out by applying a fixed load (1g) to one particle | grain using a micro compression tester, and analyzing the recovery behavior after removing the load.

The flexible particles preferably have a 1 g strain expressed as a percentage of L3 / Dn as a percentage of 30% or more when the compression displacement when a load of 1 g is applied is L3 and the particle diameter is Dn. If the 1 g strain of the flexible particles is less than 30%, the effect of suppressing the occurrence of seal break and liquid crystal contamination may not be sufficiently exhibited. A more preferable lower limit of 1 g strain of the flexible particles is 40%.
The 1 g strain of the flexible particles can be derived by applying a load of 1 g to each particle using a micro compression tester and measuring the amount of displacement at that time.

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

The flexible particles have a preferable lower limit of the glass transition temperature of −200 ° C. and a preferable upper limit of 40 ° C. The lower the glass transition temperature of the flexible particles, the better the sealing breakage and liquid crystal contamination. However, if the temperature is lower than -200 ° C, the handling of the particles may be problematic, or the sealing agent may be crushed during heating. In some cases, the sealing agent in the middle of curing and the liquid crystal come into contact with each other to cause liquid crystal contamination. When the glass transition temperature of the flexible particles exceeds 40 ° C., a gap defect may occur. The minimum with a more preferable glass transition temperature of the said flexible particle | grain is -150 degreeC, and a more preferable upper limit is 35 degreeC.
In addition, the glass transition temperature of the said flexible particle shows the value measured by the differential scanning calorimetry (DSC) based on "the plastics transition temperature measuring method" of JISK7121.

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

The silicone-based particles are preferably silicone rubber particles from the viewpoint of dispersibility in the resin.
Examples of commercially available silicone particles include KMP-594, KMP-597, KMP-598, KMP-600, KMP-601, KMP-602 (manufactured by Shin-Etsu Chemical Co., Ltd.), Trefil E- 506S, EP-9215 (manufactured by Toray Dow Corning Co., Ltd.), etc., which are used by adjusting the mode particle size to be 1.07 times or more of the median particle size by classification or mixing. it can. The said silicone type particle | grains may be used independently and 2 or more types may be used together.

(Meth) acrylic particles are preferably used as the vinyl particles.
The (meth) acrylic particles can be obtained by polymerizing monomers as raw materials by a known method. Specifically, for example, a method in which a monomer is suspension-polymerized in the presence of a radical polymerization initiator, and a seed particle is swollen by absorbing the monomer into a non-crosslinked seed particle in the presence of a radical polymerization initiator. And a seed polymerization method. When the mode particle size of the obtained particles is less than 1.07 times the median particle size, the mode particle size is 1.07 times or more of the median particle size by classification or mixing. adjust.
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 it becomes easy to disperse 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.) and Dimic Beads (manufactured by Dainichi Seika Kogyo Co., Ltd.). The particle diameter can be adjusted and used so that it becomes 1.07 times or more of the middle particle diameter.

The preferable lower limit of the hardness of the flexible particles is 10, and the preferable upper limit is 50. When the hardness of the 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 soft particles is 20, and the more preferable upper limit is 40.
In addition, in this specification, the hardness of the said flexible particle means the durometer A hardness measured by the method based on JISK6253.

The content of the soft particles is preferably 15 parts by weight with respect to 100 parts by weight of the curable resin, and 50 parts by weight with a preferable upper limit. If the content of the flexible particles is less than 15 parts by weight, the elution of the sealing agent into the liquid crystal may not be sufficiently prevented. If the content of the soft particles exceeds 50 parts by weight, the obtained liquid crystal dropping method sealing agent may be inferior in applicability and adhesiveness. The minimum with more preferable content of the said flexible particle | grain is 20 weight part, and a more preferable upper limit is 40 weight part.

The sealing agent for liquid crystal dropping method of the present invention 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 can be cured quickly, it contains a (meth) acrylic resin as a curable resin and a radical polymerization initiator described later as a polymerization initiator. Preferably, it becomes possible to quickly cure the liquid crystal dropping method sealing agent of the present invention 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, 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 the (meth) acrylic resin other than the epoxy (meth) acrylate include, for example, an ester compound obtained by reacting a compound having a hydroxyl group with (meth) acrylic acid, and a (meth) acryl having a hydroxyl group on the isocyanate compound. Examples thereof include urethane (meth) acrylate obtained by reacting an acid derivative.

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

Examples of the bifunctional one of the ester compounds include 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol 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 di ( ) Acrylate, neopentyl glycol di (meth) acrylate, ethylene oxide-added bisphenol A di (meth) acrylate, propylene oxide-added bisphenol A di (meth) acrylate, ethylene oxide-added bisphenol F di (meth) acrylate, dimethylol dicyclopentadi Enil 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 diol di (meth) acrylate, etc. And the like.

Among the above ester compounds, those having three or more functions include, for example, trimethylolpropane tri (meth) acrylate, ethylene oxide-added trimethylolpropane tri (meth) acrylate, propylene oxide-added trimethylolpropane tri (meth) acrylate, caprolactone-modified tri Methylolpropane tri (meth) acrylate, ethylene oxide-added isocyanuric acid tri (meth) acrylate, glycerin tri (meth) acrylate, propylene oxide-added glycerol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, tris (meth) acryloyloxyethyl Phosphate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, di Pentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate.

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 an isocyanate compound having two isocyanate groups in the presence of a catalytic amount of a tin-based compound. be able to.

As an isocyanate compound 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, 1,6,11-undecanetriiso Aneto and the like.

Examples of the isocyanate compound include those obtained by reacting a polyol such as ethylene glycol, glycerin, sorbitol, trimethylolpropane, propylene glycol, carbonate diol, polyether diol, polyester diol, and polycaprolactone diol with an excess of an isocyanate compound. It is also possible to use chain-extended isocyanate compounds.

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). Hydroxyalkyl mono (meth) acrylates such as acrylate and 2-hydroxybutyl (meth) acrylate, ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol Mono (meth) acrylates of dihydric alcohols such as mono (meth) acrylates of trivalent alcohols such as trimethylolethane, trimethylolpropane, glycerin, etc. Epoxy (meth) acrylate of rate, and the like.

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 for the purpose of improving the adhesiveness of the sealing agent 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 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 influence of the particle size distribution of the soft 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 effect of suppressing the occurrence of springback that is likely to occur due to the flexible particles by using in combination with the flexible particles. It can be further improved.

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, it is possible to suppress the occurrence of seal breaks and liquid crystal contamination, and the flexible Springback that tends to occur by blending particles can be more effectively suppressed.
Especially, since the sealing compound for liquid crystal dropping methods obtained can be hardened rapidly with a heat | fever, a thermal radical polymerization initiator is preferable.

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.
Moreover, as an example of azo initiators other than a polymeric azo initiator, V-65, V-501 (all are the Wako Pure Chemical Industries Ltd. make) etc. are mentioned, for example.

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 radical photopolymerization initiators include IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACURE OXE01, all manufactured by Rusilin TPO ), Benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether (all manufactured by Tokyo Chemical Industry Co., Ltd.) and the like.

A cationic polymerization initiator may 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.

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

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 include organic fillers such as copolymer fine particles. These fillers may be used alone or in combination of two or more.

The preferable lower limit of the content of the filler is 10% by weight and the preferable upper limit is 70% by weight with respect to the entire liquid crystal dropping method sealing agent. When the content of the filler is less than 10% 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. The more preferable lower limit of the content of the filler is 20% by weight, and the more preferable upper limit is 60% by weight.

The sealing agent for liquid crystal dropping method of the present invention preferably 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.

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

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

The titanium black is a substance having a higher transmittance in the vicinity of the ultraviolet region, particularly for light with a wavelength of 370 to 450 nm, compared to the average transmittance for light with a wavelength of 300 to 800 nm. That is, the above-described titanium black sufficiently shields light having a wavelength in the visible light region, thereby providing light shielding properties to the sealing agent for liquid crystal dropping method of the present invention, while transmitting light having a wavelength in the vicinity of the ultraviolet region. A shading agent. As the light shielding agent contained in the liquid crystal dropping method sealing agent of the present invention, a highly insulating material is preferable, 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 one coated with an inorganic component such as zirconium or magnesium oxide can also be used. Especially, what is processed with the organic component is preferable at the point which can improve insulation more.
In addition, the liquid crystal display device manufactured using the sealing agent for liquid crystal dropping method of the present invention containing the above-described titanium black as a light-shielding agent has a sufficient light-shielding property, and thus has high contrast without light leakage. A liquid crystal display element having excellent image display quality can be realized.

Examples of commercially available titanium black include 12S, 13M, 13M-C, 13R-N, 14M-C (all manufactured by Mitsubishi Materials Corporation), Tilak D (manufactured by Ako Kasei Co., Ltd.), and the like. Can be mentioned.

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

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

The content of the light-shielding agent is preferably 5% 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. When the content of the light-shielding agent is more than 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 further includes a reactive diluent for adjusting the viscosity, a spacer such as a polymer bead for adjusting the panel gap, an antifoaming agent, a leveling agent, and a polymerization inhibitor, if necessary. In addition, additives such as other coupling agents may be contained.

The method for producing the sealing agent for liquid crystal dropping method of the present invention is not particularly limited, and for example, a curable resin using a mixer such as a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, or a three roll. And a method of mixing a polymerization initiator and / or a thermosetting agent, 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, 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.

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. Such a vertical conduction material containing the sealing agent for liquid crystal dropping method of the present invention and conductive fine particles is also one aspect of the present invention.

As the conductive fine particles, for example, metal balls, or those obtained by forming a conductive metal layer on the surface of resin fine particles can be used. Among them, the one in which the conductive metal layer is formed on the surface of the resin fine particles is preferable because the conductive connection is possible without damaging the transparent substrate due to the excellent elasticity of the resin fine particles.

The liquid crystal display element which has the sealing compound for liquid crystal dropping methods of this invention or the vertical conduction material of this invention is also one of this invention.

As a method for producing the liquid crystal display element of the present invention, for example, the sealing agent for the liquid crystal dropping method of the present invention is applied to one of two transparent substrates such as a glass substrate with electrodes such as an ITO thin film or a polyethylene terephthalate substrate. The process of forming a rectangular seal pattern by screen printing, dispenser application, etc., the liquid crystal drop method sealing agent of the present invention is uncured, and liquid crystal microdrops are dropped on the entire surface of the transparent substrate and applied immediately. And a method of superposing another substrate and a step of heating and curing the sealing agent for liquid crystal dropping method 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.

ADVANTAGE OF THE INVENTION According to this invention, the sealing compound for liquid crystal dropping methods which can satisfy | fill both suppression of a seal break and liquid-crystal contamination, and suppression of the gap defect by springback 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.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.
In addition, the sealing agent for organic EL display elements of an Example and a comparative example shall be used for manufacture of the organic EL display element whose cell gap is 5 micrometers.

(Preparation of flexible particles A)
Silicone rubber particles (manufactured by Shin-Etsu Chemical Co., Ltd., “KMP-601”) are dispersed in methanol, classified by wet sieving with a sieve having an opening of 8 μm, and those passing through the sieve are collected and dried to obtain silicone rubber particles. The soft particle A which is a classification processed product was obtained. As the sieve, a polyimide film having a hole with extremely high accuracy obtained by applying ultrahigh precision fine processing with a laser was used.
About the obtained flexible particle A, the mode particle size, the median particle size, the maximum particle size, the minimum particle size, and the average measured using a Coulter type distribution measuring device (manufactured by Beckman Coulter, “Multisizer 4”) Particle size, D90, CV value of particle size, ratio W of volume frequency from minimum particle size to particle size 2 μm smaller than median particle size, volume from particle size 2 μm less than median particle size to median particle size The frequency ratio X, the volume frequency ratio Y from the median particle diameter to the particle diameter 2 μm larger than the median particle diameter, and the volume frequency ratio Z from the particle diameter 2 μm larger than the median particle diameter to the maximum particle diameter. It is shown in Table 1.
In the measurement using the Coulter type distribution measuring apparatus, 0.1 g of particles were added to 10 g of methanol to be acclimatized, ultrasonic dispersion was performed for 5 minutes to prepare a particle dispersion, and the electrolyte “ISOTON II” (Beckman in the sample stand) was prepared. The obtained particle dispersion was poured into a beaker containing (manufactured by Coulter) with a dropper until the display concentration of the measuring device reached 5%. The measurement was performed twice, and the arithmetic average value of the calculated values was used.

(Preparation of flexible particles B)
Silicone rubber particles (manufactured by Shin-Etsu Chemical Co., Ltd., “KMP-601”) are dispersed in methanol, classified by wet sieving with a sieve with an opening of 8 μm, collected through a sieve, and then recovered with a 5 μm opening. Wet sieve classification was performed using a sieve of No. 5, and the remaining material on the sieve was recovered and dried to obtain flexible particles B which were classified products of silicone rubber particles. As the sieve, a polyimide film having a hole with extremely high accuracy obtained by applying ultrahigh precision fine processing with a laser was used.
About the obtained flexible particle B, the mode particle diameter, the median particle diameter, the maximum particle diameter, the minimum particle diameter, the average particle diameter, D90, and the CV value of the particle diameter, W, X measured in the same manner as the flexible particle A , Y, and Z are shown in Table 1.

(Preparation of flexible particles C)
Silicone rubber particles (manufactured by Shin-Etsu Chemical Co., Ltd., “KMP-601”) are dispersed in methanol, subjected to wet sieving with a 10 μm mesh sieve, and those that have passed through the sieve are collected and dried to obtain silicone rubber particles. The soft particle C which is a classification treatment product of was obtained. As the sieve, a polyimide film having a hole with extremely high accuracy obtained by applying ultrahigh precision fine processing with a laser was used.
About the obtained flexible particle C, the mode particle diameter, the median particle diameter, the maximum particle diameter, the minimum particle diameter, the average particle diameter, D90, and the CV value of the particle diameter, W, X, measured in the same manner as the flexible particle A , Y, and Z are shown in Table 1.

(Preparation of flexible particles D)
Silicone rubber particles (manufactured by Shin-Etsu Chemical Co., Ltd., “KMP-601”) are fed with a precision air classifier (Nisshin Engineering Co., Ltd., “Turbo Classifier TC-15”) at a supply speed of 5 kg / h and a rotational speed of 10,000 rpm. Classification was performed to obtain flexible particles D.
About the obtained flexible particle D, the mode particle size, the median particle size, the maximum particle size, the minimum particle size, the average particle size, D90, and the CV value of the particle size, W, X, measured in the same manner as the flexible particle A , Y, and Z are shown in Table 1.

(Preparation of flexible particles E)
Powder mixing of 55 parts by weight of silicone resin particles (Momentive Performance Materials, Tospearl 1100) and 45 parts by weight of silicone resin particles (Mostive Performance Materials, Tospearl 2000B) The mixture was uniformly stirred and mixed using a vessel (“FM mixer (FM5RC / I)” manufactured by Nippon Coke Kogyo Co., Ltd.) to obtain flexible particles E.
About the obtained flexible particle E, the mode particle diameter, the median particle diameter, the maximum particle diameter, the minimum particle diameter, the average particle diameter, D90, and the CV value of the particle diameter, W, X, which were measured in the same manner as the flexible particle A , Y, and Z are shown in Table 1.

(Preparation of flexible particles F)
75 parts by weight of polytetramethylene glycol diacrylate, 21 parts by weight of styrene, and 4 parts by weight of benzoyl peroxide were mixed and dissolved uniformly to obtain a monomer mixture. The obtained monomer mixture was put into a reaction vessel containing 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 had a predetermined particle size. . Subsequently, reaction was performed for 9 hours in 85 degreeC nitrogen atmosphere, and the unclassified polymer particle was obtained. The obtained unclassified polymer particles were washed several times with hot water and dried. Then, it was dispersed in methanol and classified by wet sieving with a sieve having an opening of 10 μm, and the material that passed through the sieving was collected and dried to obtain flexible particles F that were classified into vinyl particles. As the sieve, a polyimide film having a hole with extremely high accuracy obtained by applying ultrahigh precision fine processing with a laser was used.
About the obtained flexible particle F, the mode particle diameter, the median particle diameter, the maximum particle diameter, the minimum particle diameter, the average particle diameter, D90, and the CV value of the particle diameter, W, X measured in the same manner as the flexible particle A , Y, and Z are shown in Table 1.

(Preparation of flexible particles G)
75 parts by weight of polytetramethylene glycol diacrylate, 21 parts by weight of styrene, and 4 parts by weight of benzoyl peroxide were mixed and dissolved uniformly to obtain a monomer mixture. The obtained monomer mixture was put into a reaction vessel containing 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 had a predetermined particle size. . Subsequently, reaction was performed for 9 hours in 85 degreeC nitrogen atmosphere, and the unclassified polymer particle was obtained. The obtained unclassified polymer particles were washed several times with hot water and dried. Thereafter, the mixture was dispersed in methanol, and subjected to wet sieving with a sieve having an opening of 8 μm. The particles that passed through the sieving were collected and dried to obtain flexible particles G that were classified into vinyl particles. As the sieve, a polyimide film having a hole with extremely high accuracy obtained by applying ultrahigh precision fine processing with a laser was used.
About the obtained flexible particle G, the mode particle diameter, the median particle diameter, the maximum particle diameter, the minimum particle diameter, the average particle diameter, D90, and the CV value of the particle diameter, W, X measured in the same manner as the flexible particle A , Y, and Z are shown in Table 1.

Example 1
As a curable resin, 70 parts by weight of a bisphenol A type epoxy acrylate (manufactured by Daicel Ornex, "EBECRYL3700") and 30 parts by weight of a bisphenol F type epoxy resin (manufactured by Mitsubishi Chemical Corporation, "jER806"), as a thermal radical polymerization initiator 7 parts by weight of a polymeric azo initiator (Wako Pure Chemical Industries, “VPE-0201”), 8 parts by weight of sebacic acid dihydrazide (manufactured by Otsuka Chemical, “SDH”) as a thermosetting agent, and 30 parts by weight of flexible particles A Parts, silica as a filler (manufactured by Admatechs, “Admafine SO-C2”) and 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., “KBM-” as a silane coupling agent) 403 ") 1 part by weight, and stirred with a planetary stirrer (Shinky Corporation," Awatori Nertaro "). After, to obtain a liquid crystal dropping process sealant uniformly mixed with the ceramic three roll.

(Examples 2 to 10, Comparative Examples 1 to 4)
In accordance with the blending ratios described in Tables 2 and 3, each material was mixed using a planetary stirrer (“Shinky Netaro” manufactured by Shinky Co., Ltd.) in the same manner as in Example 1, and then further 3 rolls. The sealing agents for liquid crystal dropping methods of Examples 2 to 10 and Comparative Examples 1 to 4 were prepared.
The “KMP-601 unclassified product” used in Comparative Example 1 was obtained by using silicone rubber particles (manufactured by Shin-Etsu Chemical Co., Ltd., “KMP-601”) as they were without classification. The “KMP-600 unclassified product” used is a silicone rubber particle (“KMP-600” manufactured by Shin-Etsu Chemical Co., Ltd.) used without being classified. The “9701 unclassified product” used in Comparative Example 3 was used. "Product" is a silicone elastomer composite particle (Toray Dow Corning Co., Ltd., "9701 Cosmetic Powder") that is used as it is without classification. Table 1 shows the median particle diameter, maximum particle diameter, minimum particle diameter, average particle diameter, D90, CV value of particle diameter, W, X, Y, and Z.

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

(Cell gap)
One part by weight of spacer particles (“Micropearl SI”, manufactured by Sekisui Chemical Co., Ltd.) having an average particle size of 4.7 μm per 100 parts by weight of the sealant for each liquid crystal dropping method obtained in Examples and Comparative Examples is a planetary type. 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, " In SHOTMASTER 300 "), a sealing agent (main seal) is applied so as to draw a rectangular frame on one of the two transparent electrode substrates with an ITO thin film, and then the cell is further maintained in a vacuum. A one-round sealant (dummy seal) was applied to the outer periphery. Thereafter, fine droplets of TN liquid crystal (manufactured by Chisso Corporation, “JC-5001LA”) were applied dropwise by a liquid crystal dropping device, and the other transparent substrate was bonded by a vacuum bonding device under a vacuum of 5 Pa. The cell after bonding was irradiated with 100 mW / cm ² of ultraviolet light for 30 seconds using a high-pressure mercury lamp, and then heated at 125 ° C. for 60 minutes to thermally cure the sealant to obtain a liquid crystal display element.
When the cell gap of the obtained liquid crystal display element was measured, the case where the inside of the cell was uniformly 4 to 5 μm was indicated as “、”, and the case where the gap of 4 to 5 μm was taken almost throughout the cell was indicated as “◯”. The cell gap was evaluated as “Δ” when there were many or wide portions where a gap of 4 to 5 μm was not taken in the cell, and “x” when the cell could not be formed. The results are shown in Tables 2 and 3.

(Liquid crystal contamination)
Regarding the liquid crystal display element obtained by the evaluation of “(cell gap)”, the display unevenness generated in the liquid crystal (particularly the corner portion) around the seal portion was visually observed, and the case where there was no display unevenness was ”,“ ○ ”when there is almost no display unevenness,“ △ ”when display unevenness is clearly confirmed, and“ × ”when severe display unevenness is confirmed or when a cell cannot be formed Contamination was evaluated. The results are shown in Tables 2 and 3.

(Evaluation of soft particles taken out from sealant)
0.5 parts by weight of each liquid crystal dropping method sealing agent obtained in Examples and Comparative Examples was put into 30 parts by weight of ethanol, stirred at 35 ° C. for 1 hour, and then filtered to perform sealing. The flexible fine particles were taken out from.
About the soft particles taken out from each sealant, the mode particle size, the median particle size, the maximum particle size, the minimum particle size, the average particle size, and the particles were measured in the same manner as in the above-mentioned “(Preparation of flexible particles A)”. The diameter CV values, W, X, Y, and Z are shown in Table 4.

ADVANTAGE OF THE INVENTION According to this invention, the sealing compound for liquid crystal dropping methods which can satisfy | fill both suppression of a seal break and liquid-crystal contamination, and suppression of the gap defect by springback 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.

Claims (9)

A liquid crystal dropping method sealing agent used for manufacturing a liquid crystal display element by a liquid crystal dropping method,
Containing a curable resin, a polymerization initiator and / or a thermosetting agent, and soft particles,
The flexible particles in the particle size distribution state, and are most frequent particle size or 1.07 times the median particle size,
The curable resin includes a (meth) acrylic resin,
The flexible particles include silicone-based particles and / or vinyl-based particles,
The liquid crystal dropping method sealing agent , wherein the content of the flexible particles is 15 parts by weight or more and 50 parts by weight or less with respect to 100 parts by weight of the curable resin . The sealing agent for liquid crystal dropping method according to claim 1, wherein the soft particles have a D90 in the cumulative distribution of less than 1.40 times the median particle diameter in the particle size distribution. In the particle size distribution, the flexible particle has a volume frequency ratio of W (%) from the minimum particle size to a particle size 2 μm smaller than the median particle size, and from a particle size 2 μm larger than the median particle size to the maximum particle size. 3. The sealing agent for liquid crystal dropping method according to claim 1, wherein W / Z ≧ 1.1 when the volume frequency ratio is Z (%). The flexible particles have a particle size distribution in which the volume frequency ratio from the particle diameter 2 μm smaller than the median particle diameter to the median particle diameter is X (%), and the particle diameter is 2 μm larger than the median particle diameter. 4. The sealing agent for liquid crystal dropping method according to claim 1, wherein X + Y ≧ 60 when the volume frequency ratio is up to Y (%). In the particle size distribution, the soft particles have a total volume frequency from a particle size 2 μm larger than the median particle size to a maximum particle size of less than 10% of the total, and 2 μm from the minimum particle size to the median particle size. The total of the volume frequency to a small particle diameter is less than 20% of the whole, The sealing compound for liquid crystal dropping methods of Claim 1, 2, 3 or 4 characterized by the above-mentioned. 6. The liquid crystal dropping method according to claim 1, wherein the flexible particles have a maximum particle size of 100% or more of a cell gap of the liquid crystal display element and 5 to 50 [mu] m. Sealing agent. 7. A sealing agent for liquid crystal dropping method according to claim 1, further comprising a light shielding agent. A vertical conduction material comprising the sealing agent for a liquid crystal dropping method according to claim 1, 2, 3, 4, 5, 6 or 7, and conductive fine particles. A liquid crystal display element comprising the sealing agent for a liquid crystal dropping method according to claim 1, or the vertical conduction material according to claim 8.