CN105900004B - Sealant for liquid crystal dropping process, vertical conduction material, and liquid crystal display element - Google Patents

Abstract

An object of this invention is to provide the sealing compound for liquid crystal dropping methods which can satisfy both suppression of seal breakage and liquid crystal contamination, and suppression of gap failure due to rebound. Moreover, the objective of this invention is to provide the vertical conduction material and liquid crystal display element manufactured using this sealing compound for liquid crystal dropping methods. The present invention is a liquid crystal dropping process sealant used in the manufacture of a liquid crystal display element using a liquid crystal dropping process, the liquid crystal dropping process sealing compound containing a curable resin, a polymerization initiator and/or a thermosetting agent, and soft particles, In the particle size distribution of the above-mentioned soft particles, the mode particle diameter is 1.07 times or more the median particle diameter.

Description

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

technical field

This invention relates to the sealing compound for liquid crystal dropping methods which can achieve both the suppression of seal breakage and liquid crystal contamination, and the suppression of gap defect by springback. Moreover, this invention relates to the vertical conduction material and liquid crystal display element manufactured using this sealing compound for liquid crystal dropping methods.

Background technique

In recent years, from the viewpoint of shortening tact time and optimizing the amount of liquid crystal used, the method of manufacturing liquid crystal display elements such as liquid crystal display cells has become mainstream from the conventional vacuum injection method as disclosed in, for example, Patent Document 1 and Patent Document 2 The liquid crystal dropping method called a dropping process using a photothermal combination curing sealant.

In the dropping process, first, a rectangular seal pattern is formed on one of the two transparent substrates with electrodes using a dispenser. Then, in a state where the sealant is not cured, fine droplets of liquid crystal are dropped on the entire frame of the transparent substrate, another transparent substrate is immediately superimposed, and the sealing portion is irradiated with light such as ultraviolet rays to pre-cure, and a liquid crystal display is produced. element. When the bonding of the substrates is performed under reduced pressure, a liquid crystal display element can be produced with extremely high efficiency.

However, in modern times when various mobile devices with liquid crystal panels, such as cellular phones and portable game consoles, have become widespread, downsizing of the devices is the most desired issue. As a method for downsizing, narrowing the frame of the liquid crystal display portion, for example, arranging the position of the sealing portion 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 a dropping process, there may be problems such as a portion where light cannot reach the sealing portion due to the black matrix, a portion where the photocurable resin is not sufficiently illuminated to cure, and Since the uncured sealant is in contact with the liquid crystal, the liquid crystal enters the sealant, the seal is broken and the liquid crystal leaks, and the uncured photocurable resin is eluted after the pre-curing process, and the liquid crystal is contaminated.

prior art literature

Patent Literature

Patent Document 1: Japanese Patent Laid-Open No. 2001-133794

Patent Document 2: International Publication No. 02/092718

SUMMARY OF THE INVENTION

Invention to solve problem

An object of this invention is to provide the sealing compound for liquid crystal dropping methods which can satisfy both suppression of seal breakage and liquid crystal contamination, and suppression of gap failure due to rebound. Moreover, the objective of this invention is to provide the vertical conduction material and liquid crystal display element manufactured using this sealing compound for liquid crystal dropping methods.

means to solve the problem

The present invention relates to a liquid crystal dropping process sealant used for the manufacture of a liquid crystal display element using a liquid crystal dropping process, the liquid crystal dropping process sealing compound containing a curable resin, a polymerization initiator and/or a thermosetting agent, and soft particles, In the particle size distribution of the soft particles, the mode particle size is 1.07 times or more the median particle size.

The present invention is described in detail below.

The inventors of the present invention have studied to suppress the occurrence of seal breakage and liquid crystal contamination by blending soft particles in the sealing compound for liquid crystal dropping methods so that the soft particles act as barriers between other sealing compound components and liquid crystals.

However, when such soft 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 research by the present inventors, it was found that, by blending soft particles having a mode particle size larger than a median particle size by a specified value or more in particle size distribution, it is possible to obtain both seal breakage and suppression of liquid crystal contamination and cause The sealing compound for liquid crystal dropping processes which suppresses the gap defect by springback has completed this invention.

The sealing compound for liquid crystal dropping methods of this invention is used for manufacture of the liquid crystal display element by a liquid crystal dropping method.

The sealing compound for liquid crystal dropping methods of the present invention contains soft particles.

When manufacturing a liquid crystal display element, the said flexible particle|grains become an obstacle between other sealing compound components and a liquid crystal, and it has the effect|action which prevents liquid crystal from entering a sealing compound, and the sealing compound is eluted to a liquid crystal. Moreover, by mix|blending the said flexible particle|grains, it can prevent that a board|substrate is misaligned until a sealant is hardened after bonding a board|substrate.

In the particle size distribution of the above-mentioned soft particles, the mode particle diameter is 1.07 times or more the median particle diameter. By making the mode particle diameter of the soft particles 1.07 times or more the median particle diameter, it is possible to achieve both seal breakage and suppression of liquid crystal contamination and suppression of cell gap defects due to springback. In the particle size distribution of the above-mentioned soft particles, the mode particle diameter is preferably larger than 1.07 times the median particle diameter, and more preferably larger than 1.10 times.

It should be noted that, in this specification, the mode particle diameter, median particle diameter, maximum particle diameter, minimum particle diameter, and average particle diameter of the above-mentioned soft particles refer to those obtained by measuring particle size distribution using a Coulter-type particle size distribution analyzer. value of . MULTISIZER 4 (manufactured by Beckman Coulter Co., Ltd.) or the like can be used as the above-mentioned Coulter-type distribution measuring apparatus. Specifically, 0.1 g of particles are added to 10 g of methanol to dissolve, and ultrasonic dispersion is performed for 5 minutes to prepare a particle dispersion. The obtained particle dispersion liquid was injected into the beaker containing the electrolytic solution "ISOTON II" (manufactured by Beckman Coulter Co., Ltd.) in the sample holder until the concentration indicated by the measuring device became 5% with a dropper. By forming this concentration, a reproducible measurement value can be obtained. The measurement was performed twice, and the arithmetic mean of the calculated values was used.

The above-mentioned "moderate particle size" refers to the particle size showing the maximum frequency of the particle size distribution based on the volume frequency, and the particle size distribution measured using the above-mentioned Coulter-type particle size distribution measuring apparatus may use a computer system connected to data processing. (Beckman Coulter Co., Ltd. product) device calculation. In the measuring apparatus, the pore diameter of the pores is set to 50 μm, the measurement range of 1 to 30 μm is divided into 300 parts, the frequency value is calculated on a volume basis, and the particle diameter showing the maximum frequency can be calculated.

The above-mentioned "median particle size" refers to the particle size when the volume of particles larger than this particle size accounts for 50% of the volume of all particles in the particle size distribution based on the volume frequency, and can be measured using the above-mentioned Coulter-type particle size distribution analyzer. The particle size distribution measured was calculated using an apparatus connected to a computer system for data processing (manufactured by Beckman Coulter). In the measuring device, the pore diameter of the pores is set to 50 μm, the measurement range of 1 to 30 μm is divided into 300 parts, the frequency value is calculated on a volume basis, and the 50% particle diameter is calculated from the smaller volume integral ratio as median particle size.

The above-mentioned "maximum particle size" means that in the particle size distribution measured using the above-mentioned Coulter-type particle size distribution analyzer, as the particle size increases from the mode particle size, the volume frequency continuously decreases, and the particle cannot be detected immediately after the particle size distribution. The previous particle size was taken as the maximum particle size. In addition, since the particle|grains whose volume frequency is detected discontinuously are highly likely to be aggregated particles, they are excluded from the maximum particle diameter.

The above-mentioned "minimum particle size" is set to 1.05 μm, which is the lower limit of detection when a hole of 50 μm is used, regardless of the sample to be measured.

The above-mentioned "average particle diameter" can be calculated using an apparatus connected to a computer system for data processing (manufactured by Beckman Coulter Co., Ltd.) in the particle size distribution measured using the above-mentioned Coulter-type particle size distribution measuring apparatus. In the measuring apparatus, the pore diameter of the pores is set to 50 μm, the range of the measurement range of 1 to 30 μm is divided into 300 parts, and the average particle diameter can be calculated on a volume basis.

"D90" described later refers to the particle size when the volume of particles larger than this particle size accounts for 10% of the volume of all particles in the particle size distribution based on volume frequency, and can be measured using the above-mentioned Coulter-type particle size distribution analyzer. The particle size distribution of , was calculated using an apparatus connected to a computer system for data processing (manufactured by Beckman Coulter). In the measuring apparatus, the pore diameter of the pores is set to 50 μm, the measurement range of 1 to 30 μm is divided into 300 parts, and the 90% particle diameter can be calculated as D90 from the smaller one of the volume integral ratio.

In order to more effectively balance the suppression of seal breakage and liquid crystal contamination with the suppression of defective cell gaps due to springback, in the particle size distribution of the soft particles, D90 in the cumulative distribution is preferably less than 1.40 times the median particle size, more preferably less than 1.35 times.

The particle size distribution of the above-mentioned soft particles ranges from the smallest particle diameter to the smallest particle diameter to 2 μm smaller than the median particle diameter, from the viewpoint of more effectively balancing the suppression of seal breakage and liquid crystal contamination with the suppression of cell gap defects due to springback. When the ratio of the volume frequency of the particle diameter is set to W (%), and the ratio of the volume frequency from the particle diameter 2 μm larger than the median diameter to the maximum particle diameter is set to Z (%), it is preferable that W/Z≥ 1.1, more preferably W/Z≥1.2.

In the particle size distribution of the above-mentioned soft particles, the particle size distribution of the above-mentioned soft particles ranges from a particle size 2 μm smaller than the median particle size to a When the ratio of the volume frequency of the median particle diameter is set to X (%), and the ratio of the volume frequency from the median diameter to the particle diameter 2 μm larger than the median diameter is set to Y (%), X+Y is preferable. ≥60, more preferably X+Y≥70.

The particle size distribution of the soft particles is preferably from a particle size 2 μm larger than the median particle size to the largest particle size distribution from the viewpoint of achieving more effective balance between seal breakage, suppression of liquid crystal contamination, and suppression of cell gap defects due to springback. The sum of the volume frequencies of particle diameters, that is, the above-mentioned Z is less than 10% of the whole, and the sum of the volume frequencies of particle diameters from the smallest particle diameter to 2 μm smaller than the median particle diameter, that is, the above-mentioned W is less than 20% of the whole.

As a method of making the mode particle diameter of the above-mentioned soft particles equal to or more than 1.07 times the median particle diameter, for example, a method of classifying soft particles having a mode particle diameter smaller than 1.07 times the median particle diameter; mixing particle size A method of distributing two or more different soft particles, etc.

As a method of classifying the said soft particle|grains, methods, such as wet classification and dry classification, are mentioned, for example. Among them, wet classification is preferable, and wet sieving is more preferable.

Specifically, a method of sieving a slurry in which soft particles are dispersed in an appropriate dispersion medium is preferably used, for example, using a high-precision sieve with uniform mesh.

It is preferable that the said flexible particle|grains have a maximum particle diameter of 100% or more of the cell gap of a liquid crystal display element, and are 5-50 micrometers. When the maximum particle diameter 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. When the maximum particle diameter of the said flexible particle|grains exceeds 50 micrometers, springback may arise, the adhesiveness of the sealing compound for liquid crystal dropping methods obtained may deteriorate, or gap failure may generate|occur|produce in the obtained liquid crystal display element. The more preferable upper limit of the maximum particle diameter of the said flexible particle|grains is 12 micrometers, and a more preferable upper limit is 15 micrometers.

Moreover, it is preferable that the maximum particle diameter of the said soft particle is 2.6 times or less of a cell gap. When the maximum particle size of the flexible particles exceeds 2.6 times the cell gap, springback may occur, the adhesiveness of the obtained sealing compound for liquid crystal dropping methods may deteriorate, or gap failure may occur in the obtained liquid crystal display element. A more preferable upper limit of the maximum particle diameter of the soft particles is 2.2 times the cell gap, and a more preferable upper limit is 1.7 times the cell gap.

In addition, although the cell gap of a liquid crystal display element differs depending on a display element and is not limited, the cell gap of a general liquid crystal display element is 2-10 micrometers.

In the particle size distribution of the soft particles measured by the Coulter-type distribution analyzer, the content ratio of particles having a particle diameter of 5 μm or more is preferably 60% or more in terms of volume frequency. When the content ratio of particles having a particle diameter of 5 μm or more is less than 60% in 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.

From the viewpoint of further exerting the effect of suppressing the occurrence of seal breakage and liquid crystal contamination, it is preferable that the above-mentioned soft particles contain 100% or more of the cell gaps of the liquid crystal display element in an amount of 70% or more of the particle size distribution in the entire soft particle, and more It is preferable to comprise only the particle|grains of 100% or more of the cell gap of a liquid crystal display element.

The preferable lower limit of the average particle diameter of the soft particles is 2 μm, and the preferable upper limit is 15 μm. When the average particle diameter of the said flexible particle|grains is less than 2 micrometers, the generation|occurence|production of seal breakage and liquid crystal contamination may not fully be suppressed. When the average particle diameter of the said flexible particle|grains exceeds 15 micrometers, the adhesiveness of the sealing compound for liquid crystal dropping methods obtained may deteriorate, or a gap defect may generate|occur|produce in the obtained liquid crystal display element. The more preferable lower limit of the average particle diameter of the said soft particle is 4 micrometers, the more preferable upper limit is 12 micrometers, and the more preferable lower limit is 5 micrometers.

The coefficient of variation (hereinafter, also referred to as "CV value") of the particle diameter of the soft particles is preferably 30% or less. When the CV value of the particle diameter of the soft particles exceeds 30%, cell gap failure may occur. The CV value of the particle diameter of the soft particles is more preferably 28% or less.

In addition, the CV value of particle diameter in this specification means the numerical value calculated|required by the following formula in the particle size distribution measured using the said Coulter type particle size distribution measuring apparatus.

CV value (%) of particle size=(standard deviation of particle size/average particle size)×100

Even if the maximum particle diameter, average particle diameter, and CV value of the above-mentioned soft particles are outside the above-mentioned ranges, the maximum particle diameter, average particle diameter, and CV value can be made within the above-mentioned ranges by classifying by the above-mentioned method. In addition, soft particles having a particle size smaller than 100% of the cell gap of the liquid crystal display element do not contribute to the suppression of seal breakage and liquid crystal contamination, and when mixed in a sealant, the thixotropic value may increase, so it is preferable to remove it by classification in advance .

The above-mentioned soft particles have the compressive displacement from the load value for the origin at the time of applying the load to the reverse load value as L1, and the unloading displacement from the reverse load value when the load is disconnected to the load value for the origin. When L2 is used, the recovery ratio of L2/L1 expressed as a percentage is preferably 80% or less. When the recovery rate of the said flexible particle|grains exceeds 80 %, the effect of suppressing the generation|occurrence|production of seal breakage and liquid crystal contamination may not fully be exhibited. A more preferable upper limit of the recovery rate of the soft particles is 70%, and a further preferable upper limit is 60%.

In addition, the recovery rate of the said soft particle can be derived by applying a certain load (1 g) to one particle using a micro-compression tester, and analyzing the recovery behavior after removing the load.

When the compressive displacement under a load of 1 g is defined as L3 and the particle size is defined as Dn, the flexible particles preferably have a 1 g strain expressed as a percentage of L3/Dn of 30% or more. When the strain of 1 g of the soft particles is less than 30%, the effect of suppressing the occurrence of seal breakage and liquid crystal contamination may not be sufficiently exhibited. A more preferable lower limit of the strain of 1 g of the soft particles is 40%.

In addition, the strain of 1 g of the above-mentioned soft particles can be derived by applying a load of 1 g to one particle using a micro-compression tester and measuring the amount of displacement at that time.

When the compressive displacement at the time of particle failure is defined as L4 and the particle size is defined as Dn, the above-mentioned soft particles preferably have a fracture strain expressed as a percentage of L4/Dn of 50% or more. If the fracture strain of the soft particles is less than 50%, the effect of suppressing the occurrence of seal breakage and liquid crystal contamination may not be sufficiently exhibited. A more preferable lower limit of the fracture strain of the soft particles is 60%.

In addition, the fracture strain of the said soft particle|grain can be derived by applying a load to one particle using a micro-compression tester, and measuring the displacement amount of the fracture|rupture of this particle. The above-mentioned compressive displacement L4 is calculated by taking the time at which the displacement amount discontinuously increases with respect to the load as the time at which the particles are destroyed. When the deformation does not occur even if the load is increased, the failure strain is considered to be 100% or more.

The preferable minimum of the glass transition temperature of the said soft particle is -200 degreeC, and the preferable upper limit is 40 degreeC. The lower the glass transition temperature of the soft particles, the better the seal breakage and the contamination of liquid crystals. However, if it is lower than -200°C, problems may arise in handling as particles, or the sealant may easily collapse during heating and cure. Liquid crystal contamination occurs when the sealant on the way comes into contact with liquid crystal. When the glass transition temperature of the said flexible particle|grains exceeds 40 degreeC, a clearance gap may generate|occur|produce. The more preferable lower limit of the glass transition temperature of the said soft particle is -150 degreeC, and a more preferable upper limit is 35 degreeC.

In addition, the glass transition temperature of the said soft particle|grain shows the value measured by the differential scanning calorimetry (DSC) based on the "transition temperature measurement method of plastics" of JIS K 7121.

As said flexible particle|grains, a silicone type particle, a vinyl type particle, a urethane type particle, a fluorine type particle, a nitrile type particle etc. are mentioned, for example. Among them, silicone-based particles and vinyl-based particles are preferred.

The silicone-based particles are preferably silicone rubber particles from the viewpoint of dispersibility to resins.

Examples of commercially available silicone-based 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 Corporation), etc., can be used by adjusting these by classification, mixing, etc. so that the mode particle diameter is 1.07 times or more of the median particle diameter. The above-mentioned silicone-based particles may be used alone or in combination of two or more.

As said vinyl-type particle|grains, (meth)acrylic-type particle|grains are used preferably.

The said (meth)acrylic-type particle|grains can be obtained by polymerizing the monomer used as a raw material by a well-known method. Specifically, for example, a method of suspension-polymerizing a monomer in the presence of a radical polymerization initiator can be mentioned; The method of swelling and seed crystal polymerization, etc. When the mode particle diameter of the obtained particles is less than 1.07 times the median particle diameter, the mode particle diameter is adjusted by classification, mixing, or the like so that the mode particle diameter becomes 1.07 times or more the median particle diameter.

In addition, in this specification, the said "(meth)acrylic type" means an acrylic type or a methacrylic type.

Examples of monomers used as raw materials for forming the (meth)acrylic particles include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, and (meth)acrylate. (methyl)butyl acrylate, hexyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, hexadecyl (meth)acrylate Alkyl (meth)acrylates such as alkyl esters, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, and isobornyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate Oxygen atom-containing (meth)acrylates such as esters, glycerol (meth)acrylate, polyoxyethylene (meth)acrylate, and glycidyl (meth)acrylate; (meth)acrylonitrile, etc. Nitrile monomers; monofunctional monomers such as fluorine-containing (meth)acrylates such as trifluoromethyl (meth)acrylate and pentafluoroethyl (meth)acrylate. Among them, alkyl (meth)acrylates are preferable because the Tg of the homopolymer is low and the deformation amount when a load of 1 g is applied can be increased.

In addition, in this specification, the said "(meth)acrylate" means acrylate or methacrylate.

In addition, in order to have a crosslinked structure, tetramethylolmethane tetra(meth)acrylate, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane di(meth)acrylate, trimethylolmethane Methylol propane tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, glycerol tri(meth)acrylate, glycerol di(meth)acrylate ) acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, (poly)tetramethylene di(meth)acrylate, 1,4-butane Polyfunctional monomers such as diol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, and isocyanuric acid skeleton tri(meth)acrylate. Among them, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, Poly)tetramethylene di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate.

In all monomers, the preferable lower limit of the usage-amount of the said crosslinkable monomer is 1 weight%, and a preferable upper limit is 90 weight%. By making the usage-amount of the said crosslinking monomer to be 1 weight% or more, solvent resistance improves, and it becomes easy to disperse|distribute uniformly without causing problems, such as swelling, when knead|mixing with various sealant raw materials. When the usage-amount of the said crosslinkable monomer is 90 weight% or less, a recovery rate can be lowered|hung and problems, such as a springback, are hard to generate|occur|produce. The more preferable lower limit of the usage-amount of the said crosslinkable monomer is 3 weight%, and a more preferable upper limit is 80 weight%.

Furthermore, in addition to these acrylic monomers, styrene-based monomers such as styrene and α-methylstyrene; vinyl such as methyl vinyl ether, ethyl vinyl ether, and propyl vinyl ether can also be used base ethers; vinyl acetate, vinyl butyrate, vinyl laurate, vinyl stearate and other acid vinyl esters; ethylene, propylene, isoprene, butadiene and other unsaturated hydrocarbons; vinyl chloride, Halogen-containing monomers such as vinyl fluoride and chlorostyrene; triallyl (iso)cyanurate, triallyl trimellitate, divinylbenzene, diallyl phthalate, diallyl Acrylamide, diallyl ether, γ-(meth)acryloyloxypropyltrimethoxysilane, trimethoxysilylstyrene, vinyltrimethoxysilane and other monomers.

Moreover, as said vinyl-type particle|grains, a polydivinylbenzene particle, a polychloroprene particle, a butadiene rubber particle etc. can be used, for example.

Examples of commercially available urethane-based particles include ARTPEARL (manufactured by Negami Kogyo Co., Ltd.), DAIMIC BEADS (manufactured by Dainissei Chemical Co., Ltd.), and the like, and these can be adjusted by classification, mixing, or the like. The mode particle diameter was used so as to be 1.07 times or more the median particle diameter.

The preferable lower limit of the hardness of the soft particles is 10, and the preferable upper limit is 50. When the hardness of the said flexible particle|grains exceeds 50, the adhesiveness of the sealing compound for liquid crystal dropping methods obtained may deteriorate, or a gap defect may generate|occur|produce in the obtained liquid crystal display element. The more preferable lower limit of the hardness of the said soft particle is 20, and the more preferable upper limit is 40.

In addition, in this specification, the hardness of the said soft particle|grain means the durometer A hardness measured by the method based on JIS K 6253.

With respect to 100 parts by weight of curable resin, the preferable lower limit of the content of the flexible particles is 15 parts by weight, and the preferable upper limit is 50 parts by weight. When content of the said flexible particle|grains is less than 15 weight part, the elution of a sealing compound to a liquid crystal may not fully be prevented. When content of the said flexible particle|grains exceeds 50 weight part, the coating property and adhesiveness of the sealing compound for liquid crystal dropping methods obtained may deteriorate. The more preferable lower limit of content of the said soft particle is 20 weight part, and a more preferable upper limit is 40 weight part.

The sealing compound for liquid crystal dropping methods of this invention contains curable resin.

It is preferable that the said curable resin contains a (meth)acrylic-type resin.

The sealing compound for liquid crystal dropping methods of the present invention preferably contains a (meth)acrylic resin as a curable resin and a radical polymerization initiator described later as a polymerization initiator in order to enable rapid curing, and the present invention can be made by heating only. The sealing compound for liquid crystal dropping process is cured quickly, and the occurrence of liquid crystal contamination can be sufficiently suppressed even in a liquid crystal display element with a narrow frame design. Therefore, it is more preferable to contain a (meth)acrylic resin and a thermal radical polymerization initiator described later. .

It is more preferable that the said curable resin contains epoxy (meth)acrylate.

In addition, in this specification, the said "(meth)acrylic-type resin" means the resin which has a (meth)acryloyl group, and the said "(meth)acryloyl group" means an acryl group or a methacryloyl group. In addition, the said "epoxy (meth)acrylate" means the compound which made all epoxy groups in an epoxy resin react with (meth)acrylic acid.

Examples of epoxy resins used as raw materials for synthesizing the above epoxy (meth)acrylates include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, 2,2'-Diallyl bisphenol A type epoxy resin, hydrogenated bisphenol type epoxy resin, propylene oxide addition bisphenol A type epoxy resin, resorcinol type epoxy resin, biphenyl type Epoxy resin, sulfide epoxy resin, diphenyl ether epoxy resin, dicyclopentadiene epoxy resin, naphthalene epoxy resin, phenol novolac epoxy resin, o-cresol novolac Novolac epoxy resin, dicyclopentadiene novolac epoxy resin, biphenyl novolac epoxy resin, naphthol novolac epoxy resin, glycidylamine epoxy resin, alkyl polyvalent Alcohol-type epoxy resins, rubber-modified epoxy resins, glycidyl ester compounds, bisphenol A-type episulfide resins, etc.

As what is marketed among the said bisphenol A epoxy resins, jER828EL, jER1001, jER1004 (all are made by Mitsubishi Chemical Corporation), Epiclon 850-S (made by DIC Corporation), etc. are mentioned, for example.

As what is marketed among the said bisphenol F-type epoxy resins, jER806, jER4004 (all are the Mitsubishi Chemical Corporation make) etc. are mentioned, for example.

As what is marketed among the said bisphenol S-type epoxy resins, Epiclon EXA1514 (made by DIC Corporation) etc. are mentioned, for example.

Examples of commercially available 2,2'-diallylbisphenol A epoxy resins include RE-810NM (manufactured by Nippon Kayaku Co., Ltd.).

As what is marketed among the said hydrogenated bisphenol-type epoxy resins, Epiclon EXA7015 (made by DIC Corporation) etc. are mentioned, for example.

As what is marketed among the said propylene oxide addition bisphenol A type epoxy resin, EP-4000S (made by ADEKA company) etc. are mentioned, for example.

As what is marketed among the said resorcinol-type epoxy resins, EX-201 (made by Nagasechemtex 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 & Sumitomo Metal Chemical Co., Ltd.) etc. is mentioned, for example.

As what is marketed among the said diphenyl ether type epoxy resins, YSLV-80DE (made by Nippon-Steel Sumigin Chemical Co., Ltd.) etc. is mentioned, for example.

As what is marketed among the said dicyclopentadiene-type epoxy resins, EP-4088S (made by ADEKA company) etc. are mentioned, for example.

As what is marketed among the said naphthalene-type epoxy resins, Epiclon HP4032, Epiclon EXA-4700 (all made by DIC Corporation) etc. are mentioned, for example.

As what is marketed among the said phenol novolak epoxy resins, Epiclon N-770 (made by DIC Corporation) etc. are mentioned, for example.

As what is marketed among the said o-cresol novolak-type epoxy resins, Epiclon N-670-EXP-S (made by DIC Corporation) etc. are mentioned, for example.

As what is marketed among the said dicyclopentadiene novolak-type epoxy resins, Epiclon HP7200 (made by DIC Corporation) etc. are mentioned, for example.

As what is marketed among the said biphenyl novolak epoxy resin, NC-3000P (made by Nippon Kayaku Co., Ltd.) etc. are mentioned, for example.

As what is marketed among the said naphthol novolak-type epoxy resins, ESN-165S (made by Nippon-Steel Sumigin Chemical Co., Ltd.) etc. is mentioned, for example.

As what is marketed among the said glycidylamine type epoxy resins, jER630 (made by Mitsubishi Chemical Corporation), Epiclon 430 (made by DIC Corporation), TETRAD-X (made by Mitsubishi Gas Chemical Corporation), etc. are mentioned, for example.

Examples of commercially available alkyl polyol type epoxy resins include ZX-1542 (manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.), Epiclon 726 (manufactured by DIC Corporation), and Epolight 80MFA (manufactured by Kyoeisha Chemical Co., Ltd.) ), Denacol EX-611 (manufactured by Nagase Chemtex), and the like.

As what is marketed among the said rubber-modified epoxy resins, YR-450, YR-207 (all are Nippon Steel & Sumitomo Metal Chemical Co., Ltd. make), Epolead PB (Daicel company make), etc. are mentioned, for example.

As what is marketed among the said glycidyl ester compound, Denacol EX-147 (made by Nagase Chemtex Corporation) etc. are mentioned, for example.

As what is marketed among the said bisphenol A type episulfide resin, jERYL-7000 (made by Mitsubishi Chemical Corporation) etc. are mentioned, for example.

As other commercially available products among the above epoxy resins, for example, YDC-1312, YSLV-80XY, YSLV-90CR (all manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd.), XAC4151 (manufactured by Asahi Kasei Corporation), jER1031, jER1032 (all manufactured by Mitsubishi Chemical Corporation), EXA-7120 (manufactured by DIC Corporation), TEPIC (manufactured by Nissan Chemical Corporation), and the like.

Examples of commercially available epoxy (meth)acrylates include EBECRYL860, EBECRYL3200, EBECRYL3201, EBECRYL3412, EBECRYL3600, EBECRYL3700, EBECRYL3701, EBECRYL3702, EBECRYL3703, EBECRYL3800, EBECRYL6040, EBECRYLRDX6318All2 (all are Company), 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 Ester1600A, Epoxy Ester 3000M, Epoxy Ester 3000A, Epoxy Ester 200EA, Epoxy Ester400EA (all manufactured by Kyoeisha Chemical Co., Ltd.), Denacol Acrylate DA-141 , Denacol Acrylate DA-314, Denacol Acrylate DA-911 (all manufactured by Nagase chemtex) and the like.

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

Examples of monofunctional products in the ester compound obtained by reacting a compound having a hydroxyl group with the above-mentioned (meth)acrylic acid include methyl (meth)acrylate, ethyl (meth)acrylate, and (methyl) acrylate. ) Propyl acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (meth)acrylic acid n-octyl ester, 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-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate ester, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentenyl (meth)acrylate, benzyl (meth)acrylate, 2-methoxyethyl (meth)acrylate ester, 2-ethoxyethyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, methoxyethylene glycol (methyl) ) acrylate, methoxy polyethylene glycol (meth) acrylate, phenoxy diethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, (meth) Tetrahydrofurfuryl acrylate, ethyl carbitol (meth)acrylate, (meth)acrylate-2,2,2-trifluoroethyl, (meth)acrylate 2,2,3,3-tetrafluoro Propyl ester, 1H,1H,5H-octafluoropentyl (meth)acrylate, imide (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate , 2-(meth)acryloyloxyethyl succinate, 2-(meth)acryloyloxyethyl hexahydrophthalate, 2-(meth)acryloyloxyethyl 2-hydroxyl Propyl phthalate, 2-(meth)acryloyloxyethyl phosphate, glycidyl (meth)acrylate, and the like.

Among the above-mentioned ester compounds, bifunctional ester compounds include, for example, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, and 1,6-butanediol di(meth)acrylate. Hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, ethylene glycol di(meth)acrylate ester, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 2-n-butyl-2-ethyl-1 ,3-propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate ) acrylate, ethylene oxide addition bisphenol A di(meth)acrylate, propylene oxide addition bisphenol A di(meth)acrylate, ethylene oxide addition bisphenol F di(meth)acrylate ) acrylate, dimethylol dicyclopentadiene di(meth)acrylate, ethylene oxide modified isocyanurate di(meth)acrylate, 2-hydroxy-3-(meth)acryloyl Oxypropyl (meth)acrylate, carbonate diol di(meth)acrylate, polyether diol di(meth)acrylate, polyester diol di(meth)acrylate, polycaprolactone Ester diol di(meth)acrylate, polybutadiene diol di(meth)acrylate, etc.

Among the above-mentioned ester compounds, tri- or more functional ester compounds include, for example, trimethylolpropane tri(meth)acrylate, ethylene oxide-added trimethylolpropane tri(meth)acrylate, cyclic Oxypropane addition trimethylolpropane tri(meth)acrylate, caprolactone modified trimethylolpropane tri(meth)acrylate, ethylene oxide addition isocyanuric acid tri(meth)acrylic acid Esters, glycerol tri(meth)acrylate, propylene oxide addition glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tri(meth)acryloyloxyethyl phosphate, bis(trihydroxy) methylpropane) tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate and the like.

The above-mentioned urethane (meth)acrylate can be obtained, for example, by adding 2 equivalents of a (meth)acrylic acid derivative having a hydroxyl group to 1 equivalent of an isocyanate compound having two isocyanate groups in a catalytic amount of tin-based react in the presence of the compound.

As an isocyanate compound used as a raw material of the said urethane (meth)acrylate, isophorone diisocyanate, 2, 4- toluene diisocyanate, 2, 6- toluene diisocyanate, hexamethylene can be mentioned, for example diisocyanate, trimethylhexamethylene diisocyanate, diphenylmethane-4,4'-diisocyanate (MDI), hydrogenated MDI, polymeric MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate , Toluidine diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, tris(isocyanatophenyl) phosphorothioate, tetramethylxylene Diisocyanate, 1,6,11-undecanetriisocyanate, etc.

In addition, as the above-mentioned isocyanate compound, for example, ethylene glycol, glycerol, sorbitol, trimethylolpropane, propylene glycol, carbonate glycol, polyether glycol, polyester glycol, polycaprolactone can also be used. The chain-extended isocyanate compound obtained by reacting a polyhydric alcohol such as a diol with an excess amount of an isocyanate compound.

As a (meth)acrylic acid derivative which has a hydroxyl group which becomes a raw material of the said urethane (meth)acrylate, (meth)acrylic acid 2-hydroxyethyl, (meth)acrylic acid 2- Hydroxypropyl esters such as hydroxypropyl, 4-hydroxybutyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, etc.; ethylene glycol, propylene glycol, 1,3-propylene glycol, 1 , 3-butanediol, 1,4-butanediol, polyethylene glycol and other dihydric alcohols such as mono(meth)acrylate, trimethylolethane, trimethylolpropane, glycerin and other trihydric alcohols Epoxy (meth)acrylates such as mono(meth)acrylate or di(meth)acrylate, bisphenol A type epoxy acrylate, etc.

Examples of commercially available urethane (meth)acrylates include M-1100, M-1200, M-1210, M-1600 (all manufactured by Toagosei Co., Ltd.), EBECRYL230, and EBECRYL270 、EBECRYL4858、EBECRYL8402、EBECRYL8804、EBECRYL8803、EBECRYL8807、EBECRYL9260、EBECRYL1290、EBECRYL5129、EBECRYL4842、EBECRYL210、EBECRYL4827、EBECRYL6700、EBECRYL220、EBECRYL2220(均为Daicel－Allnex公司制)、Artresin UN－9000H、Artresin UN－9000A、Artresin UN -7100, Artresin UN-1255, Artresin UN-330, Artresin UN-3320HB, Artresin UN-1200TPK, Artresin SH-500B (all manufactured by Negami Kogyo 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 are new Nakamura Chemical Industry Co., Ltd. Company), AH-600, AT-600, UA-306H, AI-600, UA-101T, UA-101I, UA-306T, UA-306I (all manufactured by Kyoeisha Chemical Co., Ltd.), etc.

The above-mentioned (meth)acrylic resin preferably has a hydrogen-bonding unit such as a -OH group, -NH- group, and -NH ₂ group in terms of suppressing adverse effects on liquid crystals.

Moreover, it is preferable that the said (meth)acrylic-type resin has 2-3 (meth)acryloyl groups in a molecule|numerator from the height of reactivity.

The said curable resin may contain an epoxy resin for the purpose of improving the adhesiveness etc. of the sealing compound for liquid crystal dropping methods obtained.

As said epoxy resin, the epoxy resin used as a raw material for synthesizing the said epoxy (meth)acrylate, a partial (meth)acrylic-type modified epoxy resin, etc. are mentioned, for example.

In addition, in the present specification, the above-mentioned partially (meth)acrylic-based modified epoxy resin refers to a resin having at least one epoxy group and one (meth)acryloyl group in one molecule. It is obtained by making a part of epoxy groups of resin which has 2 or more epoxy groups react with (meth)acrylic acid.

Among the above-mentioned partially (meth)acrylic-based modified epoxy resins, UVACURE 1561 (manufactured by Daicel-Allnex) and the like are mentioned as commercially available ones.

When the said epoxy resin is contained as the said curable resin, the preferable upper limit of the ratio of an epoxy group with respect to the total amount of (meth)acryloyl group and an epoxy group in the said whole curable resin is 50 mol%. When the ratio of the said epoxy group exceeds 50 mol%, the solubility with respect to liquid crystal of the sealing compound for liquid crystal dropping methods obtained may become high, and liquid crystal contamination may arise, and the display performance of the obtained liquid crystal display element may deteriorate. The more preferable upper limit of the ratio of the said epoxy group is 20 mol%.

The sealing compound for liquid crystal dropping methods of this invention contains a polymerization initiator and/or a thermosetting agent.

Among them, it is preferable to contain a radical polymerization initiator as a polymerization initiator. Rebound is not only affected by the particle size distribution of the soft particles described above, but also by the curing speed of the sealant. The above-mentioned radical polymerization initiator can remarkably accelerate the curing speed compared with the thermosetting agent. Therefore, by using the above-mentioned radical polymerization initiator in combination with the above-mentioned soft particles, it is possible to suppress the occurrence of springback that is easily generated by the above-mentioned soft particles. The effect is better.

As said radical polymerization initiator, the thermal radical polymerization initiator which generate|occur|produces a radical by heating, the photoradical polymerization initiator which generate|occur|produces a radical by light irradiation, etc. are mentioned.

As described above, the above-mentioned radical polymerization initiator has an extremely fast curing speed compared with a thermosetting agent, so by using a radical polymerization initiator, the occurrence of seal breakage and liquid crystal contamination can be suppressed, and by mixing the above-mentioned soft particles, it is possible to further improve the Effectively suppresses easy springback.

Among these, in order to heat and harden the sealing compound for liquid crystal dropping methods obtained rapidly, a thermal radical polymerization initiator is preferable.

As said thermal radical polymerization initiator, the thermal radical polymerization initiator which consists of an azo compound, an organic peroxide, etc. is mentioned, for example. Among them, a polymer azo initiator composed of a polymer azo compound is preferable.

In addition, in this specification, a polymeric azo initiator means the compound which has an azo group, and generates the radical which hardens a (meth)acryloyloxy group by heat and has a number average molecular weight of 300 or more.

The preferable lower limit of the number average molecular weight of the polymer azo initiator is 1,000, and the preferable upper limit is 300,000. When the number average molecular weight of the said polymeric azo initiator is less than 1000, a polymeric azo initiator may have a bad influence on a liquid crystal. When the number average molecular weight of the said polymeric azo initiator exceeds 300,000, it may become difficult to mix into a curable resin. A more preferable lower limit of the number average molecular weight of the polymeric azo initiator is 5,000, a more preferable upper limit is 100,000, a further preferable lower limit is 10,000, and a further preferable upper limit is 90,000.

In addition, in this specification, the said number average molecular weight is the value calculated|required by polystyrene conversion by measuring by gel permeation chromatography (GPC). As a column for measuring the number average molecular weight in terms of polystyrene by GPC, for example, Shodex LF-804 (manufactured by Showa Denko Co., Ltd.) and the like can be mentioned.

As said polymeric azo initiator, the polymeric azo initiator which has the structure which couple|bonded several units, such as polyalkylene oxide, polydimethylsiloxane, via an azo group, is mentioned, for example.

As the polymer azo initiator having a structure in which units such as a plurality of polyalkylene oxides are bonded via an azo group, a polymer azo initiator having a polyethylene oxide structure is preferable. Examples of such a polymer azo initiator include polycondensates of 4,4'-azobis(4-cyanovaleric acid) and polyalkylene glycol, and 4,4'-azobis A polycondensate of (4-cyanovaleric acid) and a polydimethylsiloxane having a terminal amino group, etc., for example, VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS-1001 (all manufactured by Wako Pure Chemical Industries, Ltd.), etc.

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

As said organic peroxide, ketone peroxide, peroxy ketal, hydrogen peroxide, dialkyl peroxide, peroxy ester, diacyl peroxide, peroxydicarbonate etc. are mentioned, for example.

Examples of the photoradical polymerization initiator include benzophenone-based compounds, acetophenone-based compounds, acylphosphine oxide-based compounds, titanocene-based compounds, oxime ester-based compounds, and benzoin ether-based compounds , thioxanthone, etc.

Commercially available products among the above-mentioned photo-radical polymerization initiators include, for example, IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACURE OXE01, and Lucirin TPO (all manufactured by BASF) , benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether (both are manufactured by Tokyo Chemical Industry Co., Ltd.), etc.

A cationic polymerization initiator can be used as the above-mentioned polymerization initiator.

As the above-mentioned cationic polymerization initiator, a photocationic polymerization initiator can be suitably used. The photocationic polymerization initiator described above is not particularly limited as long as it is a photocationic polymerization initiator that generates a protonic acid or a Lewis acid by light irradiation, and may be an ionic photoacid generating type or a nonionic photoacid generating type.

Examples of the photocationic polymerization initiator include onium salts such as aromatic diazonium salts, aromatic halonium salts, and aromatic sulfonium salts, iron-arene complexes, titanocene complexes, aromatic Organometallic complexes such as silanol-aluminum complexes, etc.

As what is marketed among the said photocationic polymerization initiators, ADEKA Optoma SP-150, ADEKA Optoma SP-170 (both are manufactured by ADEKA Corporation) etc. are mentioned, for example.

About content of the said polymerization initiator, a preferable minimum is 0.1 weight part with respect to 100 weight part of said curable resins, and a preferable upper limit is 30 weight part. When content of the said polymerization initiator is less than 0.1 weight part, the sealing compound for liquid crystal dropping methods obtained may not fully be hardened|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. The more preferable lower limit of content of the said polymerization initiator is 1 weight part, a more preferable upper limit is 10 weight part, and a more preferable upper limit is 5 weight part.

As said thermosetting agent, an organic acid hydrazide, an imidazole derivative, an amine compound, a polyhydric phenol type compound, an acid anhydride etc. are mentioned, for example. Among them, solid organic acid hydrazide is preferably used.

Examples of the solid organic acid hydrazide include 1,3-bis(hydrazinocarboxyethyl)-5-isopropylhydantoin, sebacic acid dihydrazide, and isophthalic acid diacyl hydrazide. Hydrazine, adipic acid dihydrazide, malonic acid dihydrazide, etc. As commercially available products, for example, Amicure VDH, Amicure UDH (all manufactured by Ajinomoto Fine-Techno Co., Ltd.), SDH, IDH, ADH ( All are Otsuka Chemical Co., Ltd.), MDH (Japan Finechem Co., Ltd.) and so on.

About content of the said thermosetting agent, a preferable minimum is 1 weight part with respect to 100 weight part of said curable resins, and a preferable upper limit is 50 weight part. When content of the said thermosetting agent is less than 1 weight part, the sealing compound for liquid crystal dropping methods obtained may not fully thermoset. When content of the said thermosetting agent exceeds 50 weight part, the viscosity of the sealing compound for liquid crystal dropping methods obtained may become too high, and coatability may worsen. The more preferable upper limit of content of the said thermosetting agent is 30 weight part.

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

As said hardening accelerator, the polyhydric carboxylic acid which has an isocyanuric-acid ring skeleton, the epoxy resin amine adduct etc. are mentioned, for example, Specifically, tris (2-carboxymethyl) isocyanuric acid is mentioned, for example. Cyanurate, tris(2-carboxyethyl)isocyanurate, tris(3-carboxypropyl)isocyanurate, bis(2-carboxyethyl)isocyanurate, and the like.

About content of the said hardening accelerator, a preferable minimum is 0.1 weight part with respect to 100 weight part of said curable resins, and a preferable upper limit is 10 weight part. When content of the said hardening accelerator is less than 0.1 weight part, the sealing compound for liquid crystal dropping methods obtained may not fully harden, or in order to harden it, it may be necessary to heat at a high temperature. When content of the said hardening accelerator exceeds 10 weight part, the adhesiveness of the sealing compound for liquid crystal dropping methods obtained may worsen.

It is preferable that the sealing compound for liquid crystal dropping methods of this invention contains a filler for the purpose of viscosity improvement, improvement of adhesiveness by a stress dispersion effect, improvement of linear expansion coefficient, improvement of the moisture resistance of hardened|cured material, etc.

Examples of the above-mentioned 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, aluminum hydroxide, glass beads, silicon nitride, barium sulfate, gypsum, calcium silicate, sericite, activated clay, aluminum nitride and other inorganic fillers; polyester particles, polyurethane particles , organic fillers such as vinyl polymer particles, acrylic polymer particles, core-shell acrylate copolymer particles, etc. These fillers may be used alone or in combination of two or more.

About content of the said filler, a preferable minimum is 10 weight% with respect to the whole sealing compound for liquid crystal dropping methods, and a preferable upper limit is 70 weight%. When content of the said filler is less than 10 weight%, the effect, such as improvement of adhesiveness, may not fully be exhibited. When content of the said filler exceeds 70 weight%, the viscosity of the sealing compound for liquid crystal dropping methods obtained may become high, and applicability|paintability may worsen. The more preferable lower limit of content of the said filler is 20 weight%, and a more preferable upper limit is 60 weight%.

It is preferable that the sealing compound for liquid crystal dropping methods of this invention contains a silane coupling agent. The above-mentioned silane coupling agent mainly functions as an adhesive adjuvant for favorably adhering a sealant to a substrate and the like.

As the above-mentioned silane coupling agent, for example, N-benzene is preferably used from the viewpoint of being excellent in the effect of improving the adhesiveness with the substrate and the like, and being chemically bonded to the curable resin to suppress the outflow of the curable resin into the liquid crystal. 3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-isocyanatopropyl Trimethoxysilane, etc. These silane coupling agents may be used alone or in combination of two or more.

About content of the said silane coupling agent, a preferable lower limit is 0.1 weight% with respect to the whole sealing compound for liquid crystal dropping methods, and a preferable upper limit is 20 weight%. When content of the said silane coupling agent is less than 0.1 weight%, the effect by mix|blending a silane coupling agent may not fully be 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 content of the said silane coupling agent is 0.5 weight%, and a more preferable upper limit is 10 weight%.

The sealing compound for liquid crystal dropping methods of this 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 compound.

As said light-shielding agent, iron oxide, titanium black, aniline black, cyanine black, fullerene, carbon black, resin-coated carbon black, etc. are mentioned, for example. Among them, titanium black is preferable.

The above-mentioned titanium black has a higher transmittance to light having a wavelength of 370 to 450 nm in the vicinity of the ultraviolet region than the average transmittance of light having a wavelength of 300 to 800 nm. That is, the above-mentioned titanium black is a light-shielding agent having a property of imparting light-shielding properties to the sealing compound for liquid crystal dropping methods of the present invention by sufficiently shielding light of wavelengths in the visible light region, while blocking light of wavelengths in the vicinity of the ultraviolet region. . As a light-shielding agent contained in the sealing compound for liquid crystal dropping methods of this invention, the thing with high insulating property is preferable, and titanium black is suitable also as a light-shielding agent with high insulating property.

The optical density (OD value) per 1 μm of the titanium black is preferably 3 or more, and more preferably 4 or more. The higher the light-shielding property of the titanium black, the better. The OD value of the titanium black has no particularly preferred upper limit, but is usually 5 or less.

For the above-mentioned titanium black, even if it is not surface-treated, sufficient effects can be exhibited, but titanium black whose surface has been treated with an organic component such as a coupling agent, or titanium black that has been treated with silicon oxide, titanium oxide, Surface-treated titanium black such as titanium black covered with inorganic components such as germanium oxide, aluminum oxide, zirconium oxide, and magnesium oxide. Among them, titanium black treated with an organic component is preferable in that the insulating properties can be further improved.

Moreover, since the liquid crystal display element manufactured using the sealing compound for liquid crystal dropping methods of the present invention containing the above-mentioned titanium black as a light-shielding agent has sufficient light-shielding properties, it has high contrast without leakage of light, and can realize excellent image display quality. of liquid crystal display elements.

Among the commercially available products of the above titanium black, for example, 12S, 13M, 13M-C, 13R-N, 14M-C (all manufactured by Mitsubishi Materials Co., Ltd.), Tilack D (manufactured by Ako Chemicals Co., Ltd.), etc. are mentioned.

The preferred lower limit of the specific surface area of the titanium black is 13 m ² /g, the preferred upper limit is 30 m ² /g, the more preferred lower limit is 15 m ² /g, and the more preferred upper limit is 25 m ² /g.

The lower limit of the volume resistivity of the titanium black is preferably 0.5 Ω·cm, the upper limit is preferably 3 Ω·cm, the lower limit is more preferably 1 Ω·cm, and the upper limit is more preferably 2.5 Ω·cm.

The primary particle size of the light-shielding agent is not particularly limited as long as it is equal to or smaller than the cell gap of the liquid crystal display element, but the lower limit is preferably 1 nm, and the upper limit is preferably 5 μm. When the primary particle diameter of the said light-shielding agent is less than 1 nm, the viscosity and thixotropy of the sealing compound for liquid crystal dropping methods obtained may become large, and workability|operativity may worsen. When the primary particle diameter of the said light-shielding agent exceeds 5 micrometers, the coating property to a board|substrate of the sealing compound for liquid crystal dropping methods obtained may worsen. The more preferable lower limit of the primary particle diameter of the said light-shielding agent is 5 nm, a more preferable upper limit is 200 nm, a more preferable lower limit is 10 nm, and a more preferable upper limit is 100 nm.

About content of the said light-shielding agent, a preferable minimum is 5 weight% with respect to the whole sealing compound for liquid crystal dropping methods, and a preferable upper limit is 80 weight%. When content of the said light-shielding agent is less than 5 weight%, sufficient light-shielding property may not be acquired. When content of the said light-shielding agent exceeds 80 weight%, the adhesiveness with respect to a board|substrate of the sealing compound for liquid crystal dropping methods obtained, the intensity|strength after hardening may fall, or drawing property may fall. The more preferable lower limit of content of the said light-shielding agent is 10 weight%, a more preferable upper limit is 70 weight%, a more preferable minimum is 30 weight%, and a more preferable upper limit is 60 weight%.

The sealing compound for liquid crystal dropping methods of the present invention may further contain a reactive diluent for adjusting the viscosity, spacers such as polymer beads for adjusting the panel gap, an antifoaming agent, a leveling agent, a polymerization inhibitor, and others. Additives such as coupling agents.

The method for producing the sealing compound for liquid crystal dropping methods of the present invention is not particularly limited, and examples thereof include the following methods: a homodisperser, a homomixer, a universal mixer, a planetary mixer, a kneader, a three-roller, etc. The mixer mixes curable resin, polymerization initiator and/or thermosetting agent, flexible particles, and additives such as a silane coupling agent added as needed.

The preferable lower limit of the viscosity measured on the conditions of 25 degreeC and 1 rpm using the E-type viscometer of the sealing compound for liquid crystal dropping methods of this invention is 50,000 Pa.s, and a preferable upper limit is 500,000 Pa.s. When the said viscosity is less than 50,000 Pa·s, or exceeds 500,000 Pa·s, the workability|operativity at the time of apply|coating the sealing compound for liquid crystal dropping methods to a board|substrate etc. may deteriorate. The more preferable upper limit of the said viscosity is 400,000 Pa·s.

A vertical conduction material can be produced by mix|blending electroconductive fine particle with the sealing compound for liquid crystal dropping methods of this invention. The vertical conduction material containing the sealing compound for liquid crystal dropping methods of such this invention, and electroconductive fine particle is also one of this invention.

As the above-mentioned conductive fine particles, for example, metal balls, fine particles in which a conductive metal layer is formed on the surfaces of resin fine particles, and the like can be used. Among them, fine particles having a conductive metal layer formed on the surfaces of the resin fine particles are preferable from the viewpoint of enabling conductive connection without damaging the transparent substrate or the like by utilizing 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 of manufacturing the liquid crystal display element of the present invention, for example, a method having the following steps can be exemplified. The process of forming a rectangular seal pattern with the sealant for liquid crystal dropping methods of the present invention, etc. by screen printing, dispenser coating, etc. on a sheet of The process of drip-coating the microdroplet of a liquid crystal in the whole frame of a transparent substrate, and overlapping another board|substrate immediately; and the process of heating and hardening the sealing compound for liquid crystal dropping methods of this invention. Moreover, before the process of heating and hardening the sealing compound for liquid crystal dropping methods of this invention, the process of irradiating light, such as an ultraviolet-ray to a sealing pattern part, and pre-hardening a sealing compound may be performed.

Invention effect

ADVANTAGE OF THE INVENTION According to this invention, the sealing compound for liquid crystal dropping methods which can achieve both the suppression of seal breakage and liquid crystal contamination, and the suppression of gap defect by springback can be provided. Moreover, according to this invention, the vertical conduction material and liquid crystal display element manufactured using this sealing compound for liquid crystal dropping methods can be provided.

Detailed ways

The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples.

In addition, the encapsulant for organic EL display elements of an Example and a comparative example was used for manufacture of the organic EL display element whose cell gap is 5 micrometers.

(Preparation of Soft Particles A)

Silicone rubber particles (manufactured by Shin-Etsu Chemical Co., Ltd., "KMP-601") were dispersed in methanol, wet sieved with an 8 μm mesh sieve, and the particles passed through the sieve were collected and dried to obtain a classification process as silicone rubber particles The soft particles A of the product. As the sieve, a sieve having extremely high-precision holes obtained by subjecting a polyimide film to ultra-high-precision microfabrication with a laser was used.

For the obtained soft particles A, the mode particle diameter, median particle diameter, maximum particle diameter, minimum particle diameter, average particle diameter, D90, CV value of particle size, ratio of volume frequency from minimum particle size to particle size 2 μm smaller than median particle size W, volume frequency from particle size smaller than median particle size 2 μm to median particle size Ratio X of particle size, Ratio Y of volume frequency from median particle diameter to particle size 2 μm larger than median particle size, Ratio Z of volume frequency from particle size 2 μm larger than median particle size to maximum particle size shown in Table 1.

Measurement by the above-mentioned Coulter-type distribution measuring apparatus 0.1 g of particles was added to 10 g of methanol to be dissolved, and ultrasonic dispersion was performed for 5 minutes to prepare a particle dispersion. Into a beaker made of ), the obtained particle dispersion was injected with a dropper until the concentration indicated by the measuring device became 5%. The measurement was performed twice, and the arithmetic mean of the calculated values was used.

(Preparation of Soft Particles B)

Silicone rubber particles (manufactured by Shin-Etsu Chemical Industry Co., Ltd., "KMP-601") were dispersed in methanol, wet sieved with a sieve of 8 μm mesh, and the particles passing through the sieve were collected, and then wet sieved with a sieve of 5 μm mesh. After sieving, the particles remaining on the sieve were collected and dried to obtain soft particles B, which are classified products of silicone rubber particles. As the sieve, a sieve having extremely high-precision holes obtained by subjecting a polyimide film to ultra-high-precision microfabrication with a laser was used.

For the obtained flexible particles B, the mode particle diameter, median particle diameter, maximum particle diameter, minimum particle diameter, average particle diameter, D90, CV value of particle diameter, W, X measured in the same manner as the flexible particle A , Y, and Z are shown in Table 1.

(Preparation of Soft Particles C)

Silicone rubber particles (manufactured by Shin-Etsu Chemical Industry Co., Ltd., "KMP-601") were dispersed in methanol, wet sieved with a 10 μm mesh sieve, and the particles that passed through the sieve were collected and dried to obtain a classification process as silicone rubber particles The soft particles C of the product. As the sieve, a sieve having extremely high-precision holes obtained by subjecting a polyimide film to ultra-high-precision microfabrication with a laser was used.

For the obtained flexible particles C, the mode particle diameter, median particle diameter, maximum particle diameter, minimum particle diameter, average particle diameter, D90, CV value of particle diameter, W, X measured in the same manner as the flexible particle A , Y, and Z are shown in Table 1.

(Preparation of Soft Particles D)

Silicone rubber particles (manufactured by Shin-Etsu Chemical Co., Ltd., "KMP-601") were classified by a precision air classifier (manufactured by Nisshin Engineering, "Turbo-Classifier TC-15") at a supply speed of 5 kg/h and a rotational speed of 10,000 rpm , to obtain soft particles D.

For the obtained flexible particles D, the mode particle diameter, median particle diameter, maximum particle diameter, minimum particle diameter, average particle diameter, D90, CV value of particle diameter, W, X measured in the same manner as the flexible particle A , Y, and Z are shown in Table 1.

(Preparation of Soft Particles E)

A powder mixer (Nippon Coke & Engineering Co. , Ltd., "FM Mixer (FM5RC/I)") uniformly stirred and mixed to obtain soft particles E.

For the obtained flexible particles E, the mode particle diameter, median particle diameter, maximum particle diameter, minimum particle diameter, average particle diameter, D90, CV value of particle diameter, W, X measured in the same manner as the flexible particles A , Y, and Z are shown in Table 1.

(Preparation of Soft 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 uniformly dissolved to obtain a monomer mixed liquid. The obtained monomer liquid mixture was put into a reactor containing a 1 wt % aqueous solution of polyvinyl alcohol, and stirred for 2 to 4 hours to adjust the particle size so that the droplets of the monomer had a predetermined particle size. Next, the reaction was carried out in a nitrogen atmosphere at 85° C. for 9 hours to obtain unclassified polymer particles. The obtained unclassified polymer particles were washed with hot water several times and dried. Then, it was made to disperse|distribute in methanol, wet sieving was performed with the sieve of 10 micrometers, and the particle|grains which passed the sieve were collected and dried, and the flexible particle F which is a classification-processed product of vinyl-type particle|grains was obtained. As the sieve, a sieve having extremely high-precision holes obtained by subjecting a polyimide film to ultra-high-precision microfabrication with a laser was used.

For the obtained flexible particles F, the mode particle diameter, median particle diameter, maximum particle diameter, minimum particle diameter, average particle diameter, D90, CV value of particle diameter, W, X measured in the same manner as the flexible particles A , Y, and Z are shown in Table 1.

(Preparation of Soft 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 uniformly dissolved to obtain a monomer mixed liquid. The obtained monomer liquid mixture was put into a reactor containing a 1 wt % aqueous solution of polyvinyl alcohol, and stirred for 2 to 4 hours to adjust the particle size so that the droplets of the monomer had a predetermined particle size. Next, the reaction was carried out in a nitrogen atmosphere at 85° C. for 9 hours to obtain unclassified polymer particles. The obtained unclassified polymer particles were washed with hot water several times and dried. Then, it was made to disperse|distribute in methanol, wet sieving was performed with the sieve of 8 micrometers, the particle|grains which passed the sieve were collect|recovered and dried, and the soft particle G which is a classification-processed product of vinyl-type particle|grains was obtained. As the sieve, a sieve having extremely high-precision holes obtained by subjecting a polyimide film to ultra-high-precision microfabrication with a laser was used.

For the obtained soft particles G, the mode particle diameter, median particle diameter, maximum particle diameter, minimum particle diameter, average particle diameter, D90, CV value of particle diameter, W, X measured in the same manner as in the flexible particle A , Y, and Z are shown in Table 1.

(Example 1)

As curable resin, 70 parts by weight of bisphenol A type epoxy acrylate (manufactured by Daicel-Allnex, "EBECRYL3700") and 30 parts by weight of bisphenol F type epoxy resin (manufactured by Mitsubishi Chemical Corporation, "jER806"), 7 parts by weight of a polymer azo initiator (manufactured by Wako Pure Chemical Industries, Ltd., "VPE-0201") as a thermal radical polymerization initiator, and sebacic acid dihydrazide (manufactured by Otsuka Chemical Co., Ltd., manufactured by Otsuka Chemical Co., Ltd.) as a thermal curing agent "SDH") 8 parts by weight, soft particles A 30 parts by weight, 10 parts by weight of silica (manufactured by Admatechs, "Admafine SO-C2") as a filler, and 3-glycidyl ether oxide as a silane coupling agent 1 part by weight of propyltrimethoxysilane (manufactured by Shin-Etsu Chemical Industry Co., Ltd., "KBM-403") was stirred with a planetary stirring device (manufactured by Thinky, "Defoaming and Stirring Taro"), and then uniformly mixed with a ceramic three-roller By mixing, the sealing compound for liquid crystal dropping methods was obtained.

(Examples 2 to 10, Comparative Examples 1 to 4)

According to the mixing ratios described in Tables 2 and 3, in the same manner as in Example 1, each material was mixed with a planetary mixer (“Defoaming and Stirring Taro” manufactured by Thinky Corporation), and then mixed with a 3-roller, thereby preparing and implementing The sealing compound for liquid crystal dropping methods of Examples 2-10 and Comparative Examples 1-4.

In addition, the "KMP-601 unclassified product" used in Comparative Example 1 was used as it is without classifying silicone rubber particles (manufactured by Shin-Etsu Chemical Co., Ltd., "KMP-601"), and the "KMP-601" used in Comparative Example 2 "KMP-600 unclassified product" is used as it is without classifying silicone rubber particles (manufactured by Shin-Etsu Chemical Co., Ltd., "KMP-600"), and "9701 unclassified product" used in Comparative Example 3 is unclassified silicone rubber particles Elastomer composite particles (manufactured by Toray Dow Corning Corporation, "9701 Cosmetic Powder") were classified and used as they were, and the mode particle diameter, median particle diameter, maximum particle diameter, minimum particle diameter, average particle diameter, and The particle size, D90, the CV value of the particle size, W, X, Y, and Z are shown in Table 1.

＜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)

Spacer particles with an average particle diameter of 4.7 μm (manufactured by Sekisui Chemical Industry Co., Ltd., “Micropearl SI”) were used as 1 part by weight relative to 100 parts by weight of the sealing compounds for liquid crystal dropping methods obtained in Examples and Comparative Examples. The obtained sealant was uniformly dispersed by a type stirring device, and the obtained sealant was filled in a syringe for a dispenser (manufactured by Musashi High-tech Co., Ltd., "PSY-10E"). SHOTMASTER300"), apply a sealant (mainseal) to one of the two transparent electrode substrates with an ITO film so as to draw a rectangular frame, and then apply a sealant (mainseal) around the outer periphery in order to keep the cell vacuum. dummy seal). Then, microdroplets of TN liquid crystal (manufactured by Chisso Corporation, "JC-5001LA") were dripped and applied by a liquid crystal dropping device, and another transparent substrate was bonded by a vacuum bonding device under a vacuum of 5 Pa. After irradiating ultraviolet rays of 100 mW/cm ² for 30 seconds to the bonded cell using a high pressure mercury lamp, the sealing compound was thermally cured by heating at 125° C. for 60 minutes to obtain a liquid crystal display element.

The cell gap of the obtained liquid crystal display element was measured. When the cell gap was uniformly 4 to 5 μm in the cell, it was regarded as “⊚”. The cell gap was evaluated as "Δ" when there were many or widely existing sites with gaps of 5 μm, and as "×" when no cells were formed. The results are shown in Tables 2 and 3.

(liquid crystal contamination)

For the liquid crystal display element obtained by the evaluation of the above-mentioned "(cell gap)", the display unevenness caused by the liquid crystal around the sealing portion (especially the corner portion) was visually observed, and when there was no display unevenness at all, it was regarded as "⊚", The liquid crystal contamination property was evaluated as "◯" when almost no display unevenness was observed, "Δ" when display unevenness was clearly observed, and "x" when severe display unevenness was observed or when cells were not formed. 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 sealant 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 take out soft fine particles from the sealant.

For the soft particles taken out from each sealant, the mode particle diameter, median particle diameter, maximum particle diameter, minimum particle diameter, average particle diameter, particle diameter and The CV values, W, X, Y, and Z of the diameter are shown in Table 4.

【Table 1】

【Table 2】

【table 3】

【Table 4】

Industrial Availability

ADVANTAGE OF THE INVENTION According to this invention, the sealing compound for liquid crystal dropping methods which can achieve both the suppression of seal breakage and liquid crystal contamination, and the suppression of gap defect by springback can be provided. Moreover, according to this invention, the vertical conduction material and liquid crystal display element manufactured using this sealing compound for liquid crystal dropping methods can be provided.

Claims (8)

1. A sealant for liquid crystal dropping process, which is used for manufacturing a liquid crystal display element by the liquid crystal dropping process,

comprises a curable resin, a polymerization initiator and/or a heat-curing agent, and soft particles,

in the particle size distribution of the soft particles, the most frequent particle diameter is 1.07 times or more of the median diameter,

the maximum particle diameter of the soft particles is more than 100% of the cell gap of the liquid crystal display element and is 5-50 μm,

the lower limit of the average particle diameter of the soft particles is 2 μm, and the upper limit thereof is 15 μm,

the coefficient of variation of the particle diameter of the soft particles is 30% or less,

the soft particles have a glass transition temperature with a lower limit of-200 ℃ and an upper limit of 40 ℃,

the lower limit of the content of the soft particles is 15 parts by weight and the upper limit is 50 parts by weight with respect to 100 parts by weight of the curable resin.

2. The sealant for liquid crystal one drop fill process according to claim 1, wherein D90 in the cumulative distribution is less than 1.40 times the median particle diameter in the particle size distribution of the soft particles.

3. The sealant for liquid crystal one drop fill process according to claim 1 or 2, wherein W/Z is 1.1 or more when W represents a ratio of a volume frequency from a minimum particle diameter to a particle diameter 2 μm smaller than a median particle diameter in a particle size distribution of the soft particles and Z represents a ratio of a volume frequency from a particle diameter 2 μm larger than the median particle diameter to a maximum particle diameter.

4. The sealant for liquid crystal one drop fill process according to claim 1 or 2, wherein X + Y is not less than 60 when a ratio of a volume frequency from a particle diameter 2 μm smaller than a median particle diameter to the median particle diameter is X% and a ratio of a volume frequency from the median particle diameter to a particle diameter 2 μm larger than the median particle diameter is Y% in a particle size distribution of the soft particles.

5. The sealant for liquid crystal dropping process according to claim 1 or 2, wherein in the particle size distribution of the soft particles, the total of the volume frequencies from the particle size larger than the median particle size by 2 μm to the maximum particle size is less than 10% of the total, and the total of the volume frequencies from the minimum particle size to the particle size smaller than the median particle size by 2 μm is less than 20% of the total.

6. The sealant for liquid crystal dropping process according to claim 1 or 2, which contains a light-shading agent.

7. A vertically conducting material comprising the sealant for liquid crystal dropping method according to claim 1, 2,3, 4, 5 or 6 and conductive fine particles.

8. A liquid crystal display element comprising the sealant for a liquid crystal dropping process according to claim 1, 2,3, 4, 5 or 6 or the vertically conducting material according to claim 7.