JP2005077641A - Sealing material for liquid crystal display element, and liquid crystal display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing material for a liquid crystal display element which can be hardened with light and which is excellent in adhesion property to a glass substrate of the liquid crystal display element subsequent to a temperature cycle test, and a liquid crystal display element using the sealing material. <P>SOLUTION: The sealing material for the liquid crystal display element is composed of a photo-curing resin composition, wherein a storage modulus E' of the photo-cured material at 25°C is 1.0×10<SP>9</SP>Pa or higher, and further a ratio E'<SB>1</SB>/E'<SB>2</SB>of the storage modulus E'<SB>1</SB>of the cured material at a temperature lower than the glass transition temperature by 40°C to the storage modulus E'<SB>2</SB>of the cured material at a temperature higher than the glass transition temperature by 40°C is 100-1,000. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a sealing agent for a liquid crystal display element that can be cured by light and has excellent adhesion to a glass substrate of a liquid crystal display element even after a thermal cycle test, and a liquid crystal display element using the same.

In recent years, electronic devices, electronic components, and the like are increasingly required to have high performance and high quality, and in particular, development of liquid crystal panels as display devices is active. Conventional liquid crystal display elements such as liquid crystal panels have been
Two transparent glass substrates with electrodes are opposed to each other at a predetermined interval, and the periphery thereof is sealed with a sealing agent to form a cell, and liquid crystal is introduced into the cell from a liquid crystal inlet provided in a part thereof. It was produced by injecting and sealing the liquid crystal injection port with a sealing agent.
In this method, first, a seal pattern in which a liquid crystal injection port using a thermosetting sealant is provided by screen printing on one of two transparent glass substrates with electrodes is formed.
Pre-baking is performed at 00 ° C. to dry the solvent in the sealant. Next, the two substrates are opposed to each other with the spacer interposed therebetween, aligned, and bonded at 110-220 ° C. for 10-90.
After adjusting the gap near the seal by hot pressing for 1 minute, 110-220 ° C in the oven
For 10 to 120 minutes to fully cure the sealant. Next, liquid crystal is injected from the liquid crystal injection port, and finally, the liquid crystal injection port is sealed with a sealing agent to produce a liquid crystal display element.

In such a method for manufacturing a liquid crystal display element, conventionally, a room temperature curing type epoxy adhesive has been used as a sealing agent for sealing a liquid crystal injection port. However, such a room temperature curable epoxy adhesive requires a long time for curing.
On the other hand, in recent years, a fast-curing sealant made of an ultraviolet curable resin composition has been used. However, the sealing agent made of such an ultraviolet curable resin composition has a problem that it has a lower adhesive force with a glass substrate than a sealing agent made of a conventional room temperature curable epoxy adhesive. In particular, when a liquid crystal display device manufactured using a sealing agent made of a conventional ultraviolet curable resin composition is subjected to an accelerated test that repeats heating and cooling, a so-called cooling cycle test, the adhesive strength of the sealing agent to the glass substrate is remarkably high. There was a strong demand for this improvement.

For a decrease in the adhesive strength to the glass substrate after the thermal cycle test of such a sealant,
For example, a method for improving the heat resistance by using a material having a high glass transition temperature after curing as a raw material for the sealing agent can be considered. However, such a sealing agent having a high glass transition temperature after curing is not suitable for use as a sealing agent when actually producing a liquid crystal display element because the adhesiveness to the glass substrate is lowered. there were.

In view of the present situation, the present invention provides a sealing agent for a liquid crystal display element that can be cured by light and has excellent adhesion to a glass substrate of a liquid crystal display element after a cooling / heating cycle test, and a liquid crystal using the same An object is to provide a display element.

The present invention is a sealing agent for a liquid crystal display element comprising a photocurable resin composition, and the cured product cured by light has a storage elastic modulus E ′ at 25 ° C. of 1.0 × 10 ⁹ Pa or more, and, _'and the storage modulus E ₂ in the glass transition temperature of from 40 ° C. higher temperature of the cured _product' storage modulus E ₁ at 40 ° C. temperature lower than the glass transition temperature of the cured product ratio E ₁ of the '/ E ₂ 'is a sealing agent for liquid crystal display elements which is 100-1000.
The present invention is described in detail below.

The sealing agent for liquid crystal display elements of the present invention (hereinafter also simply referred to as a sealing agent) is made of a photocurable resin composition.
The photocurable resin composition is polymerized and cured by irradiation with light such as ultraviolet rays.

In the sealing agent of the present invention, the lower limit of the storage elastic modulus (E ′) at 25 ° C. of the cured product cured by light is 1.0 × 10 ⁹ Pa. If it is less than 1.0 × 10 ⁹ Pa, it becomes too soft near room temperature, and the adhesive force near room temperature may not be obtained sufficiently. A more preferred lower limit is 3.0.
× 10 ⁹ Pa.
In the present specification, “storage elastic modulus (E ′)” is measured with a dynamic viscoelasticity measuring device (DMA) at a frequency of 10 Hz and a heating rate of 5 ° C./min unless otherwise specified. Mean value.

The cured product is a ratio of the storage elastic modulus E ₁ ′ at a temperature 40 ° C. lower than the glass transition temperature of the cured product and the storage elastic modulus E ₂ ′ at a temperature 40 ° C. higher than the glass transition temperature of the cured product. _{E 1} '/ E _2' is 100 to 1,000. If it is less than 100, the cured product is hard and sufficient initial adhesive strength cannot be obtained, and also leads to a decrease in adhesive strength in the low-temperature cycle test.
If it exceeds 000, the cured product becomes too soft above the glass transition temperature, leading to a decrease in adhesive strength in the thermal cycle test.
In the present specification, the “cooling cycle test” means that the sealing agent cured by irradiating light such as ultraviolet rays is held at −40 ° C. for 30 minutes and then heated and held at 85 ° C. for 30 minutes. The test which repeats the cycle cooled to -40 degreeC again about 100 or 200 times is said.

The minimum with a preferable glass transition temperature of the said hardened | cured material is 40 degreeC, and a preferable upper limit is 80 degreeC. 4
If it is lower than 0 ° C., it becomes softened at room temperature, and sufficient adhesive strength may not be obtained.
If it exceeds 1, the cured product becomes too hard, and the adhesiveness to the glass substrate after curing may decrease.
In the present specification, the “glass transition temperature” means a loss tangent (tan δ) measured by using a dynamic viscoelasticity measuring device (DMA) at a frequency of 10 Hz and a heating rate of 5 ° C./min unless otherwise specified. ).

Examples of the photocurable resin in the photocurable resin composition include (meth) acrylic acid esters, ethylene derivatives, styrene derivatives, and the like. Especially, it is preferable to use (meth) acrylic acid ester from the point that reaction advances rapidly and adhesiveness is favorable. In addition, the said (meth) acrylic acid ester means acrylic acid ester or methacrylic acid ester.

As the photocurable resin, those having a hydrogen bonding functional group in the molecule are preferable from the viewpoint of reducing elution of the photocurable resin into the liquid crystal. Moreover, as a photocurable resin, what has two or more photoreactive functional groups in 1 molecule is preferable in order not to leave unreacted resin as much as possible after hardening. The upper limit of the number of photoreactive functional groups in one molecule is preferably 6 or less. When there are more than six photoreactive functional groups in one molecule, curing shrinkage increases, which may cause a decrease in adhesive strength.
The photocurable resin has a hydrogen bonding functional group and / or a photoreactive functional group,
After the polymerization or cross-linking reaction, the residual unreacted compound is extremely small and does not contaminate the liquid crystal.

The hydrogen bonding functional group is not particularly limited as long as it is a functional group or a residue having hydrogen bonding properties. For example, —OH group, —NH ₂ group, —NHR group (R is aromatic or aliphatic). Group hydrocarbons, and derivatives thereof), those having a functional group such as —COOH group, —CONH ₂ group, —NHOH group, and —NHCO— bond, —NH— bond, —CONHCO in the molecule −
And a group having a residue such as a bond or —NH—NH— bond.
Among the hydrogen bondable functional groups, those having a urethane bond are preferable, and examples of such a photocurable resin composition include urethane (meth) acrylate resins. By containing the urethane (meth) acrylate resin, the adhesion to the glass is increased, and the adhesive force with the glass is improved.

Although it does not specifically limit as a method of obtaining the said urethane (meth) acrylate resin, For example, the method of making the acrylic acid ester monomer which has an active hydrogen group react with a diisocyanate compound; A diol compound and a diisocyanate compound are 1: 1-1 by molar ratio. It can be obtained by a method in which a prepolymer having an isocyanate group at the terminal obtained by reacting at a ratio of 1: 2 is reacted with an acrylate ester monomer having an active hydrogen group capable of completely reacting with the remaining isocyanate group. .

Examples of the diisocyanate compound include diphenylmethane diisocyanate (M
DI), tolylene diisocyanate (TDI), xylene diisocyanate (XDI), isophorone diisocyanate (IPDI), naphthylene diisocyanate (NDI), tolidine diisocyanate (TPDI), hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI) And trimethylhexamethylene diisocyanate (TMHDI). Especially, the said curable resin composition is suitably used by using urethane (meth) acrylate resin containing the following formula (1) and / or formula (2) urethane structure obtained using trimethylhexamethylene diisocyanate (TMHDI). Storage elastic modulus E ′ at 25 ° C. of a cured product cured by irradiating with UV light or the like, and
Ratio E ′ ₁ / E ′ ₂ of storage elastic modulus E ′ ₁ at a temperature 40 ° C. lower than the glass transition temperature of the cured product and storage elastic modulus E ′ ₂ at a temperature 40 ° C. higher than the glass transition temperature of the cured product.
Can be in the above-mentioned range.

The (meth) acrylate having an active hydrogen group is not particularly limited.
Those having H group: 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, glycerin dimethacrylate, 2-hydroxy-3-acryloyloxypropyl methacrylate, 2- (meth) acryloyloxyethyl-2- Hydroxyethylphthalic acid epoxy ester, pentaerythritol triacrylate, CO
Those having an OH group: (meth) acrylic acid, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, 2-acryloyloxyethyl phthalic acid and the like.

The diol compound is not particularly limited, and examples thereof include alkyl diol, polyether diol, and polyester diol.

The alkyl diol is not particularly limited. For example, ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, 1,9-nonanediol, neopentyl glycol, Examples include 1,4-cyclohexanediol.

The polyether diol is not particularly limited. For example, poly (ethylene oxide) diol, poly (propylene oxide) diol, poly (tetramethylene oxide) diol, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct Etc.

The polyester diol is not particularly limited, and examples thereof include poly (caprolactone) diol, poly (carbonate) diol, and the like, acid components such as adipic acid, succinic acid, terephthalic acid, and isophthalic acid, and ethylene glycol, diethylene glycol, 1, 4 -Polyester diol obtained by dehydration reaction with diol components such as butanediol.

These alkyl diols, polyether diols, and polyester diols may be used alone or in combination. In particular, bisphenol A is used from the viewpoint of adhesion and cure shrinkage.
Particularly preferred are ethylene oxide adducts and poly (caprolactone) diols.

The minimum with the preferable compounding quantity of the said urethane (meth) acrylate resin is 10 weight% in a photocurable resin composition, and a preferable upper limit is 60 weight%. If it is less than 10% by weight, effects such as adhesion between the cured product of the photocurable resin composition and the glass may not be obtained. If it exceeds 60% by weight, the viscosity is adjusted to be suitable as a sealing agent. It becomes difficult to do.

As a manufacturing method of the said urethane (meth) acrylate resin, for example, the said diol compound and the said diisocyanate compound are made into an organic zinc and an amine compound as a polymerization catalyst, and 80-
Acrylic ester monomer having an active hydrogen group that only reacts completely with the remaining isocyanate group by synthesizing a prepolymer having an isocyanate group at a desired end by reacting at a temperature of about 100 ° C. for about 3 to 5 hours 3 to 5 at a temperature of about 80 to 100 ° C.
Examples include a method of reacting for about an hour.

The photocurable resin composition preferably contains a photoradical polymerization initiator. The photo radical polymerization initiator is not particularly limited as long as it reacts with the photoreactive functional group of the photo curable resin by light irradiation. The acetophenone compound, benzophenone compound, benzoin compound, benzoin ether compound, acylphosphine Examples thereof include compounds that generate radicals when irradiated with ultraviolet rays, such as oxide compounds and thioxanthone compounds. Examples of such compounds include benzophenone, 2,2-diethoxyacetophenone, benzyl, benzoin isopropyl ether, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, and diethylthioxanthone. These photoinitiators may be used independently and 2 or more types may be used together.

From the viewpoint of reducing elution into the liquid crystal, the photo radical polymerization initiator preferably has a hydrogen bonding functional group in the molecule. Moreover, what a photoreactive functional group, such as a (meth) acryl group, contains in a radical photopolymerizable initiator is more preferable. By having a photoreactive functional group such as a (meth) acrylic group, the residue of the radical photopolymerization initiator after curing is chemically bonded to the cured product, and the residue is less likely to elute into the outgas or liquid crystal. . Examples of the compound that satisfies these conditions include 1- [4- (2-acryloyloxyethoxy) phenyl] -2-hydroxy-2.
-Propan-1-one (ZLI-3331, manufactured by Merck & Co., Inc.) and the like.

The hydrogen bonding functional group is not particularly limited as long as it is a functional group or a residue having hydrogen bonding properties, for example, OH group, NH ₂ group, NHR group (R is an aromatic or aliphatic hydrocarbon) , And derivatives thereof), COOH groups, CONH ₂ groups, NHOH groups, etc., and NH in the molecule
Examples thereof include groups having residues such as CO bond, NH bond, CONHCO bond, and NH-NH bond.

The minimum with the preferable compounding quantity of the said radical photopolymerization initiator is 0.1 weight part with respect to 100 weight part of said photocurable resins, and a preferable upper limit is 10 weight part. If the amount is less than 0.1 parts by weight, sufficient curing may not be obtained. If the amount exceeds 10 parts by weight, a large amount of unreacted radical photopolymerization initiator may remain, resulting in poor weather resistance. is there. A more preferred lower limit is 1 part by weight, and a more preferred upper limit is 5 parts by weight.

The photo-curable resin composition preferably further contains a silane coupling agent. The silane coupling agent has a role as an adhesion aid that improves adhesion to a glass substrate or the like.
Although it does not specifically limit as said silane coupling agent, Since it is excellent in the adhesive improvement effect with a glass substrate etc. and can prevent the outflow in a liquid crystal by chemically bonding with photocurable resin, for example, (gamma)- Aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-isocyanatopropyltrimethoxysilane, etc., or a structure in which the imidazole skeleton and alkoxysilyl group are bonded via a spacer group What consists of an imidazole silane compound which has this, etc. are used suitably. These silane coupling agents may be used alone or in combination of two or more.

The preferable lower limit of the compounding amount of the silane coupling agent in the sealing agent of the present invention is 0.1 part by weight with respect to 100 parts by weight of the photocurable resin, and the preferable upper limit is 10 parts by weight. 0.1
If the amount is less than parts by weight, the blending effect of the coupling agent may not be sufficiently exhibited.
If it exceeds the parts by weight, the excess silane coupling agent may flow out into the liquid crystal and adversely affect the orientation of the liquid crystal.

The sealing agent of the present invention may contain a filler for the purpose of improving the adhesiveness due to the stress dispersion effect and improving the linear expansion coefficient. The filler is not particularly limited, and examples thereof include silica particles, alumina, talc and the like.

The sealing agent of the present invention further includes a reactive diluent for adjusting the viscosity, a thixotropic agent for adjusting the thixotropy, a spacer such as a polymer bead for adjusting the panel gap, an antifoaming agent, and a leveling as necessary. An agent, a polymerization inhibitor, and other additives may be contained.

As a light source that can be used when irradiating light to the photocurable resin composition, as long as the photocurable resin composition exhibits photoactivity by light emitted from the light source and is a light source that generates a polymer or a crosslinked product. There is no particular limitation.
Examples of the light source include a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, an excimer laser, a metal halide lamp, a chemical lamp, a black light lamp, a microwave excitation mercury lamp, a sodium lamp, a xenon lamp, a halogen lamp, and a fluorescent lamp. ,
Sunlight, an electron beam irradiation apparatus, etc. are mentioned. Further, unnecessary wavelength components may be reduced or removed using a filter or the like, and various light sources may be used in combination.

The method for producing the sealing agent of the present invention is not particularly limited. For example, a method of mixing the above-mentioned photocurable resin, radical polymerization initiator and additives blended as necessary by a conventionally known method, etc. Is mentioned. At this time, in order to remove ionic impurities, it may be brought into contact with an ion-adsorbing solid such as a layered silicate mineral.

The sealing agent of the present invention is composed of a photocurable resin composition, and a cured product cured by light has a storage elastic modulus E ′ at 25 ° C. of 1.0 × 10 ⁹ Pa or more, and The ratio E ₁ ′ / E ₂ ′ of the storage elastic modulus E ₁ ′ at a temperature 40 ° C. lower than the glass transition temperature and the storage elastic modulus E ₂ ′ at a temperature 40 ° C. higher than the glass transition temperature of the cured product is 100 to 1000 Therefore, even after the cooling / heating cycle test, the adhesive force between the glass substrates is not reduced and gap unevenness does not occur.
Further, when the photocurable resin or the like has a hydrogen bondable functional group, the remaining unreacted compound is extremely small after the polymerization or crosslinking reaction, and the liquid crystal display element can be formed by a so-called dropping method using the sealing agent of the present invention. Even if manufactured, the liquid crystal is not contaminated.
The performance of such a photocurable resin composition is, for example, when a urethane (meth) acrylate resin having a structure represented by the above formula (1) and / or formula (2) is used as the photocurable resin. Can be achieved.
The liquid crystal display element obtained by using the sealing agent of the present invention has a reliable quality, office equipment,
It can be suitably used as a display panel for characters and symbols of home appliances, automobile meters and the like.
A liquid crystal display element using the sealing agent of the present invention is also one aspect of the present invention.

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

(Synthesis of urethane acrylate resin (1))
In a reaction flask in a dry air atmosphere, 0.05 mol of dibutyltin dilaurate, 2, 2
, 4- and 2,4,4-trimethylhexamethylene diisocyanate (Degussa, TM
HDI) 50 mol was added and heated to 80 ° C., and 100 mol of Placcel FA2D (Daicel Chemical Co., Ltd.) was slowly added dropwise to the reaction solution so that the reaction temperature did not exceed 90 ° C. The reaction was carried out at 80 ° C. until no isocyanate group remained by external absorption spectrum analysis to obtain a urethane acrylate resin (1).

(Synthesis of urethane acrylate resin (2))
In a reaction flask in a dry air atmosphere, 50 mol of 2,2,4- and 2,4,4-trimethylhexamethylene diisocyanate (Degussa, TMHDI) and 0.05 mol of dibutyltin dilaurate were placed and heated to 80 ° C. Then, 50 mol of Plaxel FA2D (manufactured by Daicel Chemical Industries) was slowly added dropwise to the reaction solution so that the reaction temperature did not exceed 90 ° C. 2 more
-50 mol of hydroxyethyl acrylate was slowly added dropwise so that the reaction temperature did not exceed 90 ° C, and after completion of the addition, the reaction was further carried out at 80 ° C until no isocyanate groups remained by infrared absorption spectrum analysis. (2) was obtained.

(Synthesis of urethane acrylate resin (3))
In a reaction flask in a dry air atmosphere, 0.05 mol of dibutyltin dilaurate, poly (
Caprolactone) diol (Placcel 205, manufactured by Daicel Chemical Industries) 90 mol
Then, 50 mol of 2,2,4- and 2,4,4-trimethylhexamethylene diisocyanate (Degussa, TMHDI) was slowly added dropwise to the reaction solution so that the reaction temperature did not exceed 90 ° C. After completion of the dropwise addition, the mixture was further heated at 80 ° C. for 3 hours. 10 mol of 2-hydroxyethyl acrylate was slowly added dropwise to the reaction solution so that the reaction temperature did not exceed 90 ° C., and after completion of the addition, the reaction was continued at 80 ° C. until no isocyanate group remained by infrared absorption spectrum analysis. To obtain a urethane acrylate resin (3).

(Example 1)
Urethane acrylate resin (1) 30 parts by weight, epoxy acrylate (EB3700, manufactured by Daicel UCB) 50 parts by weight, 2-hydroxyethyl acrylate 20 parts by weight, photo radical polymerization initiator (IR651, manufactured by Ciba Specialty Chemicals) 2 parts by weight was added and heated to 70 ° C. to dissolve the radical photopolymerization initiator, and then stirred using a planetary stirrer to obtain a mixture. Silane coupling agent (KBM403, manufactured by Shin-Etsu Chemical Co., Ltd.)
2 parts by weight was added and stirred with a planetary stirrer to obtain a sealant.

(Example 2)
Instead of the urethane acrylate resin (1) of Example 1, a urethane acrylate resin (2
) Was used in the same manner as in Example 1 except that a sealing agent was obtained.

(Example 3)
Instead of urethane acrylate resin (1) of Example 1, urethane acrylate resin (3
) Was used in the same manner as in Example 1 except that a sealing agent was obtained.

(Comparative Example 1)
Instead of the urethane acrylate resin (1) of Example 1, epoxy acrylate (70P
A sealing agent was obtained in the same manner as in Example 1 except that A, manufactured by Kyoeisha Chemical Co., Ltd. was used.

(Comparative Example 2)
Instead of the urethane acrylate resin (1) of Example 1, epoxy acrylate (160
A sealant was obtained in the same manner as in Example 1 except that 0A (manufactured by Kyoeisha Chemical Co., Ltd.) was used.

The sealing agents obtained in Examples 1 to 3 and Comparative Examples 1 and 2 were evaluated by the following methods. The results are shown in Table 1.

(1) Measurement of glass transition temperature of cured product The obtained sealing agent was applied in the form of strips of 5 × 35 × 0.35 mm, and this was applied to an ultraviolet ray having an intensity of 100 mW / cm ² using a high-pressure mercury lamp. For 30 seconds and then 120 ° C.
For 60 minutes to obtain a test specimen for measurement (1).
The maximum value of loss tangent (tan δ) measured at a frequency of 10 Hz and a heating rate of 5 ° C./min using a dynamic viscoelasticity measuring device (DMA) was taken as the glass transition temperature.

(2) Measurement of storage elastic modulus Further, using the test piece for measurement (1) prepared, using a dynamic viscoelasticity measuring device (DMA), measurement was performed at a frequency of 10 Hz and a heating rate of 5 ° C / min. Storage elastic modulus E 'at 25 ° C, storage elastic modulus E ₁ ' at a temperature 40 ° C lower than the glass transition temperature, 40 ° C lower than the glass transition temperature
The storage elastic modulus E ₂ ′ at a high temperature was determined.

(3) Adhesion test 5 μm short glass fiber spacer 5 with respect to 100 parts by weight of the photocurable resin of the obtained sealing agent
A non-alkali glass substrate (Corning Corp. # 1737) was prepared by mixing and mixing parts by weight.
The same glass substrate was bonded in a cross shape. After irradiating with an ultraviolet ray having an intensity of 100 mW / cm ² for 30 seconds using a high-pressure mercury lamp, it was further heat-treated at 120 ° C. for 60 minutes to obtain a test specimen (2) for measurement.
This measurement adhesion test piece (2) was fixed to a chuck in which the respective glass substrates were arranged up and down, and the tensile strength was determined under the condition of a tensile speed of 5 mm / sec.
Further, after holding this adhesion test piece (2) at −40 ° C. for 30 minutes, heating, holding at 85 ° C. for 30 minutes, and cooling again to −40 ° C. for 200 cycles, the above-mentioned adhesion test It was measured by the method, and was defined as the adhesive strength after the cooling and heating cycle.

ADVANTAGE OF THE INVENTION According to this invention, the sealing agent for liquid crystal display elements which can be hardened | cured with light and was excellent in adhesiveness with the glass substrate of a liquid crystal display element before and after a thermal cycle test, and a liquid crystal display element using the same are provided. it can.

Claims (6)

A sealing agent for a liquid crystal display element comprising a photocurable resin composition, wherein a cured product cured by light has a storage elastic modulus E ′ at 25 ° C. of 1.0 × 10 ⁹ Pa or more and the curing The ratio E ₁ '/ E ₂ ' between the storage elastic modulus E ₁ 'at a temperature 40 ° C lower than the glass transition temperature of the product and the storage elastic modulus E ₂ ' at a temperature 40 ° C higher than the glass transition temperature of the cured product is 100 ~ 1
The sealing agent for liquid crystal display elements characterized by being 000. The sealing agent for liquid crystal display elements according to claim 1, wherein the photocurable resin composition contains 10 to 60% by weight of at least one urethane (meth) acrylate resin as a photocurable resin. The sealing agent for liquid crystal display elements according to claim 2, wherein the urethane (meth) acrylate resin has a structure represented by the following formula (1) and / or formula (2).

The glass transition temperature of hardened | cured material is 40-80 degreeC, The sealing agent for liquid crystal display elements of Claim 1, 2, or 3 characterized by the above-mentioned. The photocurable resin composition contains a silane coupling agent.
3. A sealing agent for liquid crystal display elements according to 3 or 4. A liquid crystal display element comprising the sealing agent for a liquid crystal display element according to claim 1, 2, 3, 4 or 5.