JP2000019537A - Sealant for liquid crystal display element and liquid crystal display element using thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a sealant having flexibility capable of following a film bend and excellent in chemical resistance by contg. at least one kind of an alkoxy group free epoxy resin which is excellent in at least heat resistance and chemical resistance as an epoxy component. SOLUTION: A liq. epoxy resin at an ambient temp. and an amine having an alkylene glycol group as a curing agent are contained. As the liq. epoxy resin at the ambient temp., a bisphenol type epoxy resin, a glycidyl amine type epoxy resin and an alicyclic type epoxy resin are listed as a material excellent in heat resistance and liq. crystal resistance even further among them. A sealant for liq. crystal display having the both of liq. crystal resistance and adhesiveness can be obtained by combining these epoxy resins and the amine contg. the alkylene glycol group as the curing agent. A curing catalyst for shortening a curing time and/or lowering a curing temp. can be added to the obtained sealant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device using a plastic film or sheet as a substrate (hereinafter referred to as a liquid crystal display device).
Also called a film type liquid crystal display element. The present invention relates to a sealant having good adhesiveness, flexibility, heat resistance, and the like, which is used in (1), and a liquid crystal display device using the sealant.

[0002]

2. Description of the Related Art Liquid crystal display elements have been used as many display displays such as personal computer and word processing displays because of their thinness, light weight and low power consumption. Most of these liquid crystal display elements use glass as a substrate (hereinafter, also referred to as a glass type liquid crystal display element). However, in recent years, mounting of liquid crystal display elements on so-called mobile devices has progressed. Accordingly, liquid crystal display cells using a plastic film or sheet as a substrate have been used in part because of the demand for lightness and crushability.

A liquid crystal display device is used in a form in which liquid crystal is sealed in a substrate of the device by a sealant. The sealant needs to have an adhesive strength that is not broken by the stress applied to the liquid crystal display element, and because it is in direct contact with the liquid crystal molecules, a property that does not adversely affect the liquid crystal molecules, and further, a plastic film is used for the substrate. Since there is a need for a liquid crystal display element to display a curved surface, comprehensive characteristics having flexibility are required. In particular, in recent years, with the expansion of mobile applications, a demand for a sealant having better heat resistance than conventional ones has been increasing.

A thermosetting epoxy resin is used as a sealant for a liquid crystal display element. In contrast to a liquid crystal cell using a glass substrate, a film type liquid crystal cell using a synthetic resin film or sheet as a substrate has a glass substrate. Since the heat resistance of the synthetic resin film or sheet is lower than that of
The curing temperature of the sealant could not be set as high as when a glass substrate was used, and there was a disadvantage that the heat resistance of the sealant was poor.

Further, a film type liquid crystal display element must have flexibility which is hardly required for a glass type liquid crystal display element. For this reason, in a film type liquid crystal element, a sealant different from that of a glass substrate type liquid crystal display element has been used, or a glass sealant has been cured at a low temperature before use. For this reason, the film-type liquid crystal display element, compared with the glass-substrate-type liquid crystal display element, is one of the properties required for the sealant, especially when stored at a high temperature, because the liquid crystal is mixed into the sealant and swells. However, there is a problem in liquid crystal resistance such as a decrease in bonding strength and malfunction of the liquid crystal due to an increase in switching current of the liquid crystal due to the sealant, and a highly reliable sealant overcoming this has been demanded.

In order to solve these problems, Japanese Patent Application Laid-Open No. 18523/1988 discloses a sealant using a polyol type epoxy resin as a sealant for a film type liquid crystal display device. This can achieve the flexibility and adhesive strength of the sealant, but when the liquid crystal cell is stored at a high temperature of about 80 ° C., the swelling of the sealant and the switching current value of the liquid crystal gradually increase, and the heat resistance is still low. There were not enough problems.

In Japanese Patent Application Laid-Open No. 9-12679, 10 to 50 parts by weight of a liquid silicone-modified epoxy resin at room temperature and 90 to 50 parts by weight of a liquid bisphenol type epoxy resin at room temperature are used as sealants for film type liquid crystal display devices. ,
20 to 80 parts by weight of a trifunctional thiol curing agent liquid at room temperature, 0.5 to 5.0 parts by weight of a silane coupling agent, 1 to 10 parts by weight of amorphous silica having an average particle size of 1 μm or less,
Although a sealant containing 5 to 50 parts by weight of an inorganic filler other than amorphous silica having an average particle size of 2 μm or less as an essential component is disclosed, when a liquid crystal cell is stored at a high temperature of about 80 ° C., There is a problem that the switching current value gradually increases and the heat resistance is not yet sufficient.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a liquid crystal display device using a plastic film as a substrate. It is an object of the present invention to provide a liquid crystal display device which solves the above-mentioned problem by using a sealant having flexibility and excellent chemical resistance which can follow the above-mentioned requirements.

[0009]

Means for Solving the Problems The present inventors have conducted various studies to solve the above-mentioned problems, and as a result, as a sealing agent for a liquid crystal display element of a film type liquid crystal display element, a specific epoxy resin as a curing agent component. The inventors have found that the above problems can be solved by using a specific amine compound, and have reached the present invention. That is, the present inventors have conducted various studies on an epoxy resin and a curing agent that provide high heat resistance and chemical resistance under the heating temperature conditions in the process of assembling a cell for a film-type liquid crystal display element with high liquid crystal resistance, and as a result, as an epoxy component And a resin containing at least one epoxy resin having no heat resistance and good chemical resistance and not containing an alkoxy group.

As the epoxy resin which is liquid at room temperature, bisphenol type epoxy resins (bisphenol A type, bisphenol F type), glycidylamine type epoxy resin,
Glycidyl ester type epoxy resin, alicyclic type epoxy resin, alcohol type epoxy resin, elastomer modified epoxy resin, urethane modified epoxy resin, silicone modified epoxy resin, polysulfide type epoxy resin, etc. Materials with excellent properties are bisphenol-type epoxy resins, glycidylamine-type epoxy resins, and alicyclic epoxy resins.By combining such an epoxy resin with an amine having an alkylene glycol group as a curing agent, liquid crystal resistance and A sealant for a liquid crystal display element having compatible adhesiveness is provided.

That is, when an epoxy resin other than the bisphenol type epoxy resin, glycidylamine type epoxy resin and alicyclic type epoxy resin is combined with an amine having an alkylene glycol group, more flexibility than necessary is obtained. , Heat resistance and chemical resistance become insufficient,
As a result, liquid crystal resistance cannot be obtained, and it is not suitable as a sealant for liquid crystal display elements. The sealant composition may contain an alicyclic amine as a curing agent.

In particular, when the epoxy component and the curing agent are used in combination, the change in the specific resistance of the liquid crystal is small even when a high-temperature reliability, for example, a standing test is performed at 85 ° C., and the reliability of the liquid crystal display element is also 85 ° C. More than 500 hours. That is, it is possible to provide a highly reliable liquid crystal display element in which the rate of change in current consumption of the liquid crystal is small, there is no defective alignment near the sealant, and there is no change in liquid crystal response.

When the bisphenol type epoxy resin used in the present invention is used, the bisphenol type epoxy resin is, for example, a bisphenol A type epoxy resin represented by the following general formula (1) or a bisphenol A type epoxy resin represented by the following general formula (2). Bisphenol F type epoxy resin. Bisphenol A type epoxy resin

Embedded image (N is 0 or 1)

Bisphenol F type epoxy resin

Embedded image (N is 0 or 1.) The bisphenol-type epoxy resin used in the present invention may be a mixture of two or more types.

As a specific example of the bisphenol A type epoxy resin, for example, Epicoat 828, 834, 100
1,1004 (manufactured by Yuka Shell Epoxy Co., Ltd.), and Epicron 850, 860, 4055 (manufactured by Dainippon Ink and Chemicals, Inc.). Specific examples of the bisphenol F type epoxy resin include, for example, Epicoat 807 (manufactured by Yuka Shell Epoxy Co., Ltd.) and Epicron 830 (manufactured by Dainippon Ink and Chemicals, Inc.).

The glycidylamine type epoxy resin used in the present invention includes, for example, N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane (TGDDM), N, N'-diglycidylamino- 1,
3-diglycidyl phenyl ether (DGAGPE) and the like, and these epoxy resins are characterized in that the glycidyl group of N is directly bonded.

The alicyclic epoxy resin used in the present invention includes an epoxy resin of a type obtained by oxidizing a double bond of a cyclohexane ring with peracetic acid to epoxidize it.
For example, there may be mentioned an acyclic diepoxy acetal of the following formula (3) and a vinylcyclohexene dioxide of the following formula (4).

Embedded image

Embedded image

Further, it has been found that when a flexible epoxy resin is further mixed with the combination of the epoxy resin and the curing agent, the peel strength can be further improved. Examples of the flexible epoxy resin include an alcohol-type epoxy resin, an elastomer-modified epoxy resin, a urethane-modified epoxy resin, a polysulfide-modified epoxy resin, and a silicone oil-modified epoxy resin. Alcohol-type epoxy resin Examples of the alcohol-type epoxy resin include an epoxy resin obtained by reacting a phenolic hydroxyl group with an excess of epichlorohydrin in the presence of a caustic alkali.
Examples of the epoxy resin include monoglycidyl ethers of higher alcohols, diglycidyl ethers of 1,6-hexanediol, and diglycidyl ethers of polyoxyalkylene glycols. For example, those represented by the following formulas (5) to (8) Is mentioned.

Polyethylene glycol type

Embedded image

Propylene glycol type

Embedded image

1,6-hexanediol diglycidyl ether type

Embedded image Elastomer-modified epoxy resin Bisphenol A type epoxy resin with a terminal functional group added with liquid nitrile rubber to give flexibility, modified with carboxyl-terminal acrylonitrile-butadiene copolymer CTBN or amino-terminal ATBN There is something.

Urethane-modified epoxy resin is a resin having flexibility by introducing a urethane bond having good flexibility or abrasion resistance into the resin skeleton, and an example of which has the following structure is given as an example. .

Embedded image (In the formula, R and R ¹ represent a divalent organic group.)

Polysulfide-Modified Epoxy Resin A material having an —S— bond in the molecular skeleton and having epoxy groups (glycidyl groups) at both ends, for example, a polysulfide-modified epoxy resin represented by the following formula (10).

Embedded image As the polysulfide-modified epoxy resin, FLE
P-10, FLEP-50, FLEP-60, FLEP
-80 (trade name, manufactured by Toray Thiokol Co., Ltd.).

Silicone oil-modified epoxy resin A material having an SiO bond in the molecular skeleton and having epoxy groups at both ends, for example, a material represented by the following formula (11).

Embedded image (Wherein R represents a methyl group or a phenyl group) Each of the epoxy 1 and the epoxy 2 may contain two or more epoxy resins.

As the amine having an alkylene glycol group used in the present invention, the following formulas (12) and (1)
The polyalkylene glycol type amine represented by 3) is mentioned.

Embedded image

Embedded image

Further, in addition to the amine having an alkylene glycol group or the amine having an alkylene glycol group and an alicyclic amine, an epoxy silane, an amino silane or the like may be contained as a coupling agent.

A curing catalyst can be added to the sealant of the present invention in order to shorten the curing time of the sealant and / or to lower the curing temperature. Examples of the curing catalyst to be added include inorganic solid acids such as silica, and organic acids such as citric acid. As a curing catalyst, by containing an acid as described above, the curing reaction proceeds at a low temperature,
Low temperature can be achieved. When fine powdered silica is used as a curing catalyst, protons (-
The OH group is dissociated to become H ⁺ ), which serves as an acidic catalyst. However, since silica exerts the action of thickening the sealant as described below, it is possible to use both the thickening action and the catalytic action. .

A filler can be added to the sealant of the present invention for compatibility with screen printing. That is,
The sealant is usually formed on the substrate by a screen printing method. Therefore, it is necessary to adjust the viscosity of the sealant to about 30 to 50 Pa · S. For example, titanium oxide may be added as a filler. , Silica, alumina, calcium carbonate and the like. The filler can be used alone or in combination of two or more, and can be added to the epoxy component, the curing agent component, or both. A homogenizer or a three-roll mill is suitable for the addition method. An appropriate amount of the filler is 10 to 70 parts by weight based on 100 parts by weight of the epoxy component or the curing agent component.

A silane coupling agent can be added to the sealant of the present invention for improving the adhesive strength. Examples of the silane coupling agent, in addition to the aminosilane coupling agent, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane and the like. The addition amount of the silane coupling agent is 0.5 to 20 parts by weight, preferably 1 to 10 parts by weight based on 100 parts by weight of the epoxy resin.

As the base material of the plastic film substrate, there are a polycarbonate film, a polyethersulfone film, a polysulfone film and the like. However, since the base substrate alone has insufficient properties such as gas barrier properties and solvent resistance, an inorganic or organic coating film such as a gas barrier layer and a protective film is formed on both sides or one side of the substrate, and on top of that. An ITO film is formed.
The total thickness of the substrate is 0.1 to 0.3 mm.

Further, the present inventors studied a method for evaluating the liquid crystal resistance of the sealant, and found that the sealant was stored in the liquid crystal at a high temperature, and the specific resistance value of the liquid crystal after storage was measured. Also, by measuring the degree of swelling of the liquid crystal in the sealant, it was confirmed that the liquid crystal resistance of the sealant can be evaluated well, and according to these evaluation methods, the liquid crystal resistance of the sealant after storage at high temperature was poor. The liquid crystal has a low specific resistance value, and the liquid crystal permeates and swells into the sealant, so that the weight of the sealant increases. Those having a high specific resistance tend not to swell, and it is determined that a sealant having such performance has high liquid crystal resistance.

<Manufacturing Method of Liquid Crystal Display Element Using Plastic Film Substrate> Cleaning of the substrate surface which is formed of at least one plastic film substrate and on which an ITO electrode patterned by a known method such as a photolithography method is formed. Thereafter, an alignment film such as polyamide or polyimide is printed in an arbitrary pattern by flexographic printing. After baking at a predetermined temperature, a rubbing process is performed to complete a liquid crystal alignment process. After removing the rubbing dust by ultrasonic dry cleaning, a window frame at a position corresponding to the electrode terminal portion is opened on one or both substrates (hereinafter, referred to as a precut step). Further, ultrasonic cleaning (30-60 KHz ultrasonic water cleaning and water cleaning at a frequency near 1 MHz) is performed to completely remove dust.

On one substrate, a gap material of plastic or inorganic particles for determining the cell gap is sprayed, and on the other substrate, the sealant of the present invention is screen-printed, and the positions of both substrates are aligned. , Superimpose. The superposed pair of substrates is set in an air bag type pressure firing device and seal-baked at a temperature of 60 ° C. or less. A cut for dividing a pair of substrates fixed with a sealant into individual cells is performed (in general, a multi-cavity method in which a large number of cells are arranged on a large-area substrate is used). 10 more cells divided into individual cells
Baking is performed at a high temperature of 0 ° C. or more to improve the crosslinking reaction of the sealant. At this time, the cells are stored in a jig such as a cassette, and the cells are baked without pressure.

The liquid crystal is injected by a vacuum method utilizing a pressure difference. Since the liquid crystal is excessively injected into the cell after the injection and the cell gap is not sufficiently uniform, the cell is sealed after extruding the excess liquid crystal from the injection port. As the sealing material, a UV-curable resin is excellent in terms of productivity, but an epoxy-based thermosetting resin may be used. A polarizing plate or a polarizing plate with a retardation plate is attached to the front side (a polarizing plate for a TN type, a
Polarizing plate with retardation plate). A polarizing plate with a reflecting plate or a polarizing plate with a semi-transmissive plate is attached to the rear side to make a reflective or transflective panel. The LCD unit further includes a drive circuit and a connector for the drive circuit.

Recently, many lightweight and thin information terminals such as mobile phones, PHSs and card pagers have been produced.
The liquid crystal material characteristics required for these are a duty ratio of 1/1.
6 to 1/64, low-voltage, high-speed response STN type liquid crystal. The liquid crystal material is a mixture of about 10 types by adjusting the material type, compounding ratio, etc. according to the required characteristics (for example, duty ratio, drive voltage, response speed) for the liquid crystal display element. It was found that the demand for a liquid crystal material made the liquid crystal material more sensitive and more susceptible to the effects of surrounding materials. That is, when a material having a threshold voltage (Vth) of the liquid crystal of 1.5 V or less and a Δ 液晶 of the liquid crystal of 10 or more is used, it is particularly susceptible to peripheral materials, and an increase in current consumption due to a decrease in the specific resistance of the liquid crystal. In addition, problems such as deterioration of orientation occur. Therefore, the present invention is particularly effective in a PF-LCD using a low-voltage liquid crystal material which is easily affected by peripheral materials, and is an epoch-making seal that has achieved reliability impossible with other sealant materials. The agent is provided.

Hereinafter, embodiments of the present invention will be described.

Example 1 The following main components (epoxy components) were mixed using a homogenizer and a three-roll mill to prepare an epoxy main component. Further, the following curing agent components were mixed with a homogenizer to prepare a curing agent. 4 parts of the epoxy main agent thus prepared and 1 part of a curing agent were blended and cured at 40 ° C. for 5 hours and then at 120 ° C. for 2 hours. About 0.1g of this cured product
1 ml of liquid crystal [Rodick Co., Ltd. RDP-60429]
And stored at 85 ° C. for 4 days. Measure the specific resistance of the liquid crystal after storage (hereinafter referred to as specific resistance) and the weight change rate of the epoxy cured product before and after storage (hereinafter referred to as swelling ratio). did. As a result, the specific resistance was 1.8 × 10 ¹⁰ Ωcm, and the swelling ratio was 1.00 (not expanded).

Main agent (epoxy component) 100 parts by weight of high-purity bisphenol A type epoxy resin [Yuka Kasper Epoxy Co., Ltd. Epicoat YL-980] 40 parts by weight of titanium oxide [P-25 of Nippon Aerosil Co., Ltd.] Alumina [Nippon Aerosil Al ₂ O ₃ -C] 15 parts by weight Curing agent (curing agent component) Jeffamine T-403 100 parts by weight (amine having an alkylene glycol group: manufactured by HUNTSMAN Co.) Main agent / curing agent = 10 / 5.5

Further, a film with ITO [Teijin Co., Ltd. A
M7015C, F-100-300] was sandwiched between the above-prepared products screen-printed on a substrate from which the ITO layer was etched away, cured under the same conditions, and the 90-degree peel strength (hereinafter referred to as peel strength) was measured. The peeled surface was the interface between the substrate and the coat layer, and the adhesion to the substrate surface was sufficient.

Next, an STN panel having a 1/32 duty ratio was manufactured by the same method as the above-described method of manufacturing a PF-LCD. The sealant used was the following main agent and curing agent, and the liquid crystal was RD
P-60429. Vth of this liquid crystal is 1.38.
V and Δε were 12.9. The curing condition of the sealant was 40 ° C. for 5 hours + 120 ° C. for 2 hours. Table 1 shows the reliability of the obtained panel.

[0041]

[Table 1]

Example 2 Evaluation was carried out in the same manner as in Example 1 except that the epoxy resin of Example 1 was changed to the following, and the blends of the main agent and the curing agent were changed as follows. Main agent (epoxy component) 100 parts by weight of high-purity bisphenol A epoxy resin [Yuka Kasper Epoxy Co., Ltd. Epicoat YL-980] Titanium oxide [Nippon Aerosil Co., Ltd. P-25] 40 parts by weight Alumina [Nippon Aerosil Co., Ltd.] Al ₂ O ₃ -C] 15 parts by weight Epoxysilane (KBM403: Shin-Etsu Silicone) 9 parts by weight Curing agent (curing agent component) Jeffamine D-400 100 parts by weight (amine having alkylene glycol group: manufactured by HUNTSMAN) Curing agent = 10/7 Result Liquid crystal specific resistance 3 × 10 ¹⁰ Ωcm Swelling rate 1.2 Peel strength 400 g / 5 mm

Next, an STN panel having a 1/32 duty ratio was manufactured by the same method as the above-described method of manufacturing a PF-LCD. The sealant used was the following main agent and curing agent, and the liquid crystal was RC
4087 (manufactured by Chisso Corporation). The curing conditions of the sealant were 5 hours at 40 ° C. and 5 hours at 120 ° C. The reliability of the obtained panel is as shown in Table 2 below.

[0044]

[Table 2]

Example 3 Evaluation was carried out in the same manner as in Example 1 except that the epoxy resin of Example 1 was changed to the following, and the blends of the main agent and the curing agent were changed as follows. Main agent (epoxy component) N, N, N ', N'-tetraglycidyl-m-xylylenediamine (TETRAD-X: Mitsubishi Gas Chemical) 100 parts by weight Titanium oxide [Nippon Aerosil Co., Ltd. P-25] 50 parts by weight Alumina (Nippon Aerosil Co., Ltd. Al ₂ O ₃ -C) 15 parts by weight Hardener (hardener component) 100 parts by weight Jeffamine T-403 (amine having alkylene glycol group: manufactured by HUNTSMAN) Main agent / hardener = 2 / 3 Result Liquid crystal specific resistance 2 × 10 ¹⁰ Ωcm Swelling ratio 1.3 Peel strength 290 g / 5 mm

Next, an STN panel having a 1/32 duty ratio was manufactured by the same method as the above-described method for manufacturing a PF-LCD. The sealant used was the following main agent and curing agent, and the liquid crystal was RD
P-60429. Vth of this liquid crystal is 1.38.
V and Δε are materials of 12.9. The curing conditions of the sealant were 5 hours at 40 ° C. and 2 hours at 120 ° C. The reliability of the obtained panel is as shown in Table 3 below.

[0047]

[Table 3]

Example 4 Evaluation was carried out in the same manner as in Example 1 except that the epoxy resin of Example 1 was changed to the following, and the blends of the main agent and the curing agent were changed as follows. Main agent (epoxy component) 100 parts by weight of acyclic diepoxy acetal (Araldite CY175: Ciba Geigy) 7 parts by weight of epoxysilane (KBM403: Shin-Etsu Silicone) 20 parts by weight of titanium oxide [Nippon Aerosil Co., Ltd. P-25] 20 parts by weight Alumina [Nippon Aerosil ( Co., Ltd. Al ₂ O ₃ —C] 15 parts by weight Curing agent (curing agent component) Jeffamine T-403 100 parts by weight (amine having alkylene glycol group: manufactured by HUNTSMAN) Main agent / curing agent = 5/3 Result Liquid crystal ratio Resistance 5 × 10 ⁵ Ωcm Swelling ratio 1.0 Peel strength 380 g / 5 mm

Next, an STN panel having a 1/32 duty ratio was manufactured by the same method as the above-described method of manufacturing a PF-LCD. The sealant used was the following main agent and curing agent, and the liquid crystal was RD
P-60429. Vth of this liquid crystal is 1.38.
V and Δε are materials of 12.9. The curing conditions of the sealant were 40 ° C. for 5 hours + 120 ° C. for 2 hours, and the reliability of the obtained panel is as shown in Table 4 below.

[0050]

[Table 4]

Comparative Example 1 The curing agent of Example 1 was changed to the following polyamidoamine type.
Evaluation was performed in the same manner as in Example 1 except that the blending of the main agent and the curing agent was changed as follows. The results were as follows. Main agent (epoxy component) 100 parts by weight of high-purity bisphenol A type epoxy resin [Yuka Kasper Epoxy Co., Ltd. Epicoat YL-980] 20 parts by weight of titanium oxide [Nippon Aerosil Co., Ltd. P-25] 20 parts by weight Alumina [Nippon Aerosil Co., Ltd.] Al ₂ O ₃ -C] 15 parts by weight Curing agent (curing agent component) Tomide 296 (Fuji Kasei) 100 parts by weight Main agent / curing agent = 100/25 Result Liquid crystal specific resistance 8 × 10 ⁸ Ωcm Swelling rate 1.7 Peel strength 50g / 5mm

Next, an STN panel having a 1/32 duty ratio was manufactured by the same method as the above-described method for manufacturing a PF-LCD. The sealant used was the following main agent and curing agent, and the liquid crystal was RD
P-60429. Vth of this liquid crystal is 1.38.
V and Δε were 12.9. The curing conditions of the sealing agent were 5 hours at 40 ° C. and 5 hours at 120 ° C. The reliability of the obtained panel is as shown in Table 5 below.

[0053]

[Table 5]

Comparative Example 2 Evaluation was performed in the same manner as in Example 1 except that the epoxy resin of Example 1 was changed to the following, and the blends of the main agent and the curing agent were changed as follows. The results were as follows. Main agent (epoxy component) 100 parts by weight of high-purity bisphenol A type epoxy resin [Yuka Kasper Epoxy Co., Ltd. Epicoat YL-980] 20 parts by weight of titanium oxide [Nippon Aerosil Co., Ltd. P-25] 20 parts by weight Alumina [Nippon Aerosil Co., Ltd.] Al ₂ O ₃ -C] 15 parts by weight Curing agent (curing agent component) 100 parts by weight of aromatic amine (ancamine Z: AC I Japan Limited) Main agent / curing agent = 4/1 Result Liquid crystal specific resistance 5 × 10 ¹⁰ Ωcm Swelling rate 1.0 Peel strength 32g / 5mm

[0055]

According to the present invention, in a liquid crystal display device using a plastic film as a substrate, a flexible material capable of following the bending of the film under the heating temperature condition in the assembling process of the film type liquid crystal cell as a sealing agent for the device. And a sealing agent having excellent chemical resistance was provided.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yumi Mochizuki 1-3-6 Nakamagome, Ota-ku, Tokyo F-term in Ricoh Co., Ltd. (Reference) 2H089 HA15 MA04Y MA05Y NA24 NA25 NA32 NA44 NA58 PA16 QA06 QA11 QA16 RA05 RA10 TA01 TA04 2H090 JB03 JC07 JC17 JC18 JC19 JD12 JD14 KA05 KA08 LA03

Claims (3)

[Claims] 1. A sealing agent for a liquid crystal display element using a plastic substrate, comprising an epoxy resin which is liquid at ordinary temperature and an amine having an alkylene glycol group as a curing agent. 2. The liquid crystal display according to claim 1, wherein the epoxy resin which is liquid at room temperature is at least one selected from the group consisting of a bisphenol type epoxy resin, a glycidylamine type epoxy resin and an alicyclic type epoxy resin. Element sealant. 3. A liquid crystal display device using the sealant according to claim 1.