TWI733805B - Sealant for liquid crystal display element, vertical conduction material and liquid crystal display element - Google Patents

Abstract

The object of the present invention is to provide a sealing compound for a liquid crystal display element that has excellent adhesiveness, low liquid crystal contamination, and can obtain a liquid crystal display element having excellent display performance. In addition, an object of the present invention is to provide an upper and lower conduction material and a liquid crystal display element using this sealant for liquid crystal display elements.

The present invention is a sealing compound for liquid crystal display elements, which contains a curable resin, a polymerization initiator and/or a thermosetting agent, and the curable resin contains a compound represented by the following formula (1) and one molecule A compound having two or more epoxy groups, the content of a compound having two or more epoxy groups in one molecule of 100 parts by weight of the curable resin is 5 parts by weight or more and 25 parts by weight or less. The subsequent strength is 290 N/cm ² or more.

In formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a group represented by the following formula (2-1) or (2-2), R ³ represents a structure derived from an acid anhydride, and R ⁴ represents a ring For the structure of the oxygen compound, X represents the ring-opening structure of the lactone, n represents an integer from 1 to 6, and a represents an integer from 1 to 4.

In formula (2-1), * represents the bonding position.

In formula (2-2), b represents an integer from 0 to 8, c represents an integer from 0 to 3, d represents an integer from 0 to 8, e represents an integer from 0 to 8, and any of b, c, d is 1 or more, * indicates the bonding position.

Description

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

The present invention relates to a sealing compound for a liquid crystal display element that has excellent adhesiveness, low liquid crystal contamination, and can obtain a liquid crystal display element with excellent display performance. In addition, the present invention relates to an upper and lower conduction material and a liquid crystal display element using the sealing compound for liquid crystal display elements.

In recent years, as a method of manufacturing liquid crystal display elements, from the viewpoints of shortening the tact time and optimizing the amount of liquid crystal used, as disclosed in Patent Document 1 and Patent Document 2, the so-called The liquid crystal dropping method of the dropping method uses a light-heat combined hardening type sealant containing a curable resin, a photopolymerization initiator, and a thermosetting agent.

In the dropping method, first, a frame-shaped sealing pattern is formed by dispensing on one of two transparent substrates with electrodes. Next, when the sealant is not hardened, drop tiny drops of liquid crystal onto the entire surface of the frame of the sealant on the transparent substrate, and immediately overlap another transparent substrate, and irradiate the sealing part with light such as ultraviolet rays to temporarily harden it. After that, heating is performed to perform main curing, and a liquid crystal display element is produced. By bonding the substrates under reduced pressure, the liquid crystal display element can be manufactured with extremely high efficiency. At present, the dropping method is becoming the mainstream of the manufacturing method of the liquid crystal display element.

In addition, various mobile devices with LCD panels such as mobile phones and portable game consoles have become popular and modern, and miniaturization of the devices has become the most pressing issue. As a method of miniaturization of the device, the narrowing of the frame of the liquid crystal display can be cited, for example, the operation of arranging the position of the sealing part under the black matrix (hereinafter, also referred to as narrow frame design) is being performed. However, in the narrow frame design, since the sealant is arranged directly under the black matrix, if the drip method is performed, there is a problem that the light irradiated when the sealant is hardened by light is blocked, so that the light cannot reach To the inside of the sealant, the hardening is insufficient. In this way, if the curing of the sealant is insufficient, there is a problem that the uncured sealant component will be eluted into the liquid crystal, which may easily cause liquid crystal contamination.

With the popularization of tablet terminals or mobile terminals, liquid crystal display elements are increasingly required to have durability against impact tests and drop tests. In addition, along with the narrow frame design, the reliability of moisture resistance during driving in a high temperature and high humidity environment is required, and the sealant further requires the performance of preventing the penetration of water from the outside. That is, from the viewpoint of improving the impact resistance and moisture resistance reliability of the liquid crystal display element, it is necessary to improve the adhesion between the sealant and the substrate. However, it is difficult to produce a sealant that is excellent in adhesiveness and low in liquid crystal contamination (excellent in low liquid crystal contamination).

Patent Document 1: Japanese Patent Application Publication No. 2001-133794

Patent Document 2: Japanese Patent Laid-Open No. 5-295087

The present invention relates to a sealing compound for a liquid crystal display element that has excellent adhesiveness, low liquid crystal contamination, and can obtain a liquid crystal display element with excellent display performance. In addition, an object of the present invention is to provide an upper and lower conduction material and a liquid crystal display element using this sealant for liquid crystal display elements.

The present invention is a sealing compound for liquid crystal display elements, which contains a curable resin, a polymerization initiator and/or a thermosetting agent, and the curable resin contains a compound represented by the following formula (1) and one molecule A compound having two or more epoxy groups, the content of a compound having two or more epoxy groups in one molecule of 100 parts by weight of the curable resin is 5 parts by weight or more and 25 parts by weight or less. The subsequent strength is 290 N/cm ² or more.

In formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a group represented by the following formula (2-1) or (2-2), R ³ represents a structure derived from an acid anhydride, and R ⁴ represents a ring For the structure of the oxygen compound, X represents the ring-opening structure of the lactone, n represents an integer from 1 to 6, and a represents an integer from 1 to 4.

In formula (2-1), * represents the bonding position.

In formula (2-2), b represents an integer from 0 to 8, c represents an integer from 0 to 3, d represents an integer from 0 to 8, e represents an integer from 0 to 8, and any of b, c, d is 1 or more, * indicates the bonding position.

Hereinafter, the present invention will be described in detail.

The present inventors studied the use of the compound represented by the above formula (1) as a curable resin to obtain a sealing compound having excellent adhesiveness and low liquid crystal contamination. However, when the obtained sealant is used, especially in high-precision liquid crystal display elements, there are problems in that afterimages are generated, the contrast is lowered, or the response speed is lowered.

The inventor believes that the residual image generated by the display element is caused by the compound represented by the above formula (1) remaining in the cured product of the sealant precipitates and adheres to the alignment film, thereby causing a decrease in the alignment restriction force. That is, the inventor believes that in a high-precision liquid crystal display element with a large number of wiring lines in order to achieve high pixel density, the portion of the sealant disposed under the wiring becomes larger, and light cannot be sufficiently irradiated to the sealant due to the wiring. , The unreacted compound represented by the above formula (1) is easy to precipitate.

Therefore, the present inventors further conducted diligent studies and found that by combining the compound represented by the above formula (1) with a compound having two or more epoxy groups in one molecule, the compound is used in one molecule. The content of the compound having two or more epoxy groups is set in a specific range, and a sealing compound for liquid crystal display elements that can obtain liquid crystal display elements with excellent adhesion, low liquid crystal contamination, and excellent display performance can be obtained, thereby completing The present invention.

The sealing compound for liquid crystal display elements of this invention contains a curable resin.

The said curable resin contains the compound represented by the said formula (1). By containing the compound represented by the above formula (1), the sealing compound for liquid crystal display elements of the present invention has excellent adhesiveness and low liquid crystal contamination.

In the above formula (1), R ² represents a group represented by the above formula (2-1) or (2-2). Among them, from the viewpoint of the adhesiveness of the obtained sealant for liquid crystal display elements or the flexibility of the cured product, the above-mentioned R ^{2 is} preferably a chemical formula (2- 2) The represented group (linear oxyalkylene having 1 to 4 carbon atoms).

In the above formula (1), R ³ represents a structure derived from acid anhydride.

As said acid anhydride, phthalic anhydride, maleic anhydride, succinic anhydride, citraconic anhydride, etc. are mentioned, for example. Among them, phthalic anhydride is preferred.

In the above formula (1), R ⁴ represents a structure derived from an epoxy compound.

As the said epoxy compound, it is preferable to use the same thing as the following compound which has 2 or more epoxy groups in 1 molecule.

In the above formula (1), X represents the ring-opening structure of the lactone.

Examples of the aforementioned lactones include: β-propiolactone, β-butyrolactone, γ-butyrolactone, γ-valerolactone, δ-valerolactone, ε-caprolactone, and γ-heptanolactone , Γ-nonanolactone, γ-decanolactone, δ-decanolactone, γ-laurolactone, δ-laurolactone, γ-undecanolide, δ-undecanolide, 7-butyrolactone Group-2-oxepanone and so on. Among them, it is preferable that the carbon number of the linear part of the main skeleton is 3 to 7 when the ring is opened.

In the above formula (1), n represents an integer of 1 to 6. Among them, from the viewpoint of the adhesiveness of the obtained sealing compound for liquid crystal display elements or the flexibility of the cured product, the above-mentioned n is preferably an integer of 1 to 5.

In the above formula (1), a represents an integer of 1 to 4. Among them, from the viewpoint of improving the heat resistance of the cured product of the obtained sealing compound for liquid crystal display elements, the above a is preferably an integer of 2 to 4, and from the viewpoint of storage stability, 2 is more preferable.

The preferred lower limit of the molecular weight of the compound represented by the above formula (1) is 700, and the preferred upper limit is 2,100. When the molecular weight of the compound represented by the above formula (1) is in this range, the obtained sealing compound for liquid crystal display elements is more excellent in adhesiveness and low liquid crystal contamination.

The lower limit of the content of the compound represented by the formula (1) in 100 parts by weight of the curable resin is preferably 5 parts by weight, and the upper limit is preferably 50 parts by weight. When the content of the compound represented by the above formula (1) is in this range, the obtained sealing compound for liquid crystal display elements is more excellent in adhesiveness and low liquid crystal contamination. The more preferable upper limit of the content of the compound represented by the above formula (1) is 30 parts by weight.

The above-mentioned curable resin contains “a compound having two or more epoxy groups in one molecule (hereinafter also referred to as a “multifunctional epoxy compound”). The above-mentioned multifunctional epoxy compound is likely to cause liquid crystal contamination, so it is usually It is preferable to reduce the blending amount within a range that does not affect the adhesiveness. On the other hand, in the sealing compound for liquid crystal display elements of the present invention, not only the content of the above-mentioned polyfunctional epoxy compound is set to balance the adhesiveness and The fouling property of the liquid crystal is the intended range, and is also set to the following range. As a result, even if the compound represented by the above formula (1) is used, it is possible to suppress the precipitation of the compound represented by the above formula (1) from the cured product, thereby suppressing The obtained liquid crystal display element has afterimages, etc., and has excellent display performance.

Examples of the above-mentioned polyfunctional epoxy compound include: bisphenol A type epoxy compound, bisphenol F type epoxy compound, bisphenol S type epoxy compound, 2,2'-diallyl bisphenol A type ring Oxygen compound, hydrogenated bisphenol type epoxy compound, propylene oxide addition bisphenol A type epoxy compound, resorcinol type epoxy compound, biphenyl type epoxy compound, thioether type epoxy compound, diphenyl ether Type epoxy compound, dicyclopentadiene type epoxy compound, naphthalene type epoxy compound, phenol novolak type epoxy compound, o-cresol novolak type epoxy compound, dicyclopentadiene novolak type epoxy Compounds, biphenol novolac epoxy compounds, naphthol novolac epoxy compounds, glycidylamine epoxy compounds, alkyl polyol epoxy compounds, rubber modified epoxy compounds, glycidyl ester compounds, etc. .

The lower limit of the content of the polyfunctional epoxy compound in 100 parts by weight of the curable resin is 5 parts by weight, and the upper limit is 25 parts by weight. When the content of the polyfunctional epoxy compound is 5 parts by weight or more, the effect of suppressing the precipitation of the compound represented by the formula (1) is excellent, and the resulting liquid crystal display element can be suppressed from generating residual images. When the content of the polyfunctional epoxy compound is 25 parts by weight or less, the obtained sealing compound for liquid crystal display elements is excellent in low liquid crystal contamination. The lower limit of the content of the above-mentioned polyfunctional epoxy compound is preferably 7 parts by weight, the upper limit is preferably 23 parts by weight, the lower limit is more preferably 10 parts by weight, and the upper limit is more preferably 20 parts by weight.

The curable resin may contain other curable resins in addition to the compound represented by the formula (1) and the polyfunctional epoxy compound as long as it does not interfere with the purpose of the present invention.

As the above-mentioned other curable resin, for example, other (meth)acrylic compounds other than the compound represented by formula (1) or compounds having one epoxy group in one molecule (hereinafter, also referred to as "monofunctional ring Oxygen compounds") and so on.

Furthermore, in this specification, the aforementioned "(meth)acrylic acid" refers to acrylic acid or methacrylic acid, and the aforementioned "(meth)acrylic compound" refers to a compound having a (meth)acrylic acid group. The compound, the so-called "(meth)acryloyl" mentioned above, refers to an acrylic or methacryloyl group.

As the above-mentioned other (meth)acrylic compound, for example, a (meth)acrylate compound obtained by reacting a compound having a hydroxyl group with (meth)acrylic acid, and a (meth)acrylic acid compound obtained by reacting (meth)acrylic acid with epoxy Epoxy (meth)acrylate obtained by reacting a compound, urethane (meth)acrylate obtained by reacting a (meth)acrylic acid derivative having a hydroxyl group with an isocyanate compound, and the like. Among them, epoxy (meth)acrylate is preferred. In addition, from the viewpoint of reactivity, the (meth)acrylic compound preferably has two or more (meth)acrylic groups in one molecule.

In addition, in this specification, the above-mentioned "(meth)acrylate" means acrylate or methacrylate, and the above-mentioned "epoxy (meth)acrylate" means that the epoxy compound All of the epoxy groups react with (meth)acrylic acid.

Examples of the monofunctional among the above-mentioned (meth)acrylate compounds include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, and n-butyl (meth)acrylate. Ester, isobutyl (meth)acrylate, tertiary butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate , Isononyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, isomyristyl (meth)acrylate, stearyl (meth)acrylate, (meth) 2-hydroxyethyl acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, cyclohexyl (meth)acrylate, ( Isobornyl (meth)acrylate, dicyclopentenyl (meth)acrylate, benzyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxy (meth)acrylate Ethyl, 2-butoxyethyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, methoxyethylene glycol (meth)acrylate, methoxypolyethylene glycol ( Meth) acrylate, phenoxy diethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, ethyl carbitol ( (Meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl (meth)acrylate, (meth)acrylate 1H, 1H, 5H -Otafluoropentyl ester, imine (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, 2-(meth)propylene succinate Acetyloxyethyl, hexahydrophthalic acid 2-(meth)acryloyloxyethyl, phthalic acid 2-(meth)acryloyloxyethyl 2-hydroxypropyl, phosphoric acid 2- (Meth)acryloxyethyl, glycidyl (meth)acrylate and the like.

In addition, examples of the bifunctional one among the above-mentioned (meth)acrylate compounds include 1,3-butanediol di(meth)acrylate and 1,4-butanediol di(meth)acrylate , 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, ethylene glycol two (Meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 2-n-butyl-2 -Ethyl-1,3-propanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl diacrylate Alcohol di(meth)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, dimethylol dicyclopentadiene di(meth)acrylate, ethylene oxide modified isocyanuric acid di(meth)acrylate, (meth)acrylic acid 2-hydroxy-3-(meth)acryloxypropyl ester, carbonate diol di(meth)acrylate, polyether diol di(meth)acrylate, polyester diol di(meth) Acrylate, polycaprolactonediol di(meth)acrylate, polybutadienediol di(meth)acrylate, etc.

In addition, examples of the above-mentioned (meth)acrylate compounds having three or more functions include trimethylolpropane tri(meth)acrylate, ethylene oxide addition trimethylolpropane tri(methyl) )Acrylate, propylene oxide addition trimethylolpropane tri(meth)acrylate, caprolactone modified trimethylolpropane tri(meth)acrylate, ethylene oxide addition isocyanuric acid Acid tri(meth)acrylate, glycerol tri(meth)acrylate, propylene oxide addition glycerol tri(meth)acrylate, neopentylerythritol tri(meth)acrylate, phosphoric acid tri(meth) Acrylic oxyethyl ester, di-trimethylolpropane tetra (meth) acrylate, neopentyl erythritol tetra (meth) acrylate, dineopentyl pentaerythritol penta (meth) acrylate, dineopentyl Tetraol hexa(meth)acrylate and the like.

As said epoxy (meth)acrylate, the thing obtained by reacting an epoxy compound and (meth)acrylic acid in the presence of a basic catalyst in accordance with a conventional method, etc. are mentioned, for example.

As an epoxy compound used as a raw material for synthesizing the said epoxy (meth)acrylate, the same thing as the said polyfunctional epoxy compound can be used.

Examples of commercially available epoxy (meth)acrylates include: EBECRYL860, EBECRYL3200, EBECRYL3201, EBECRYL3412, EBECRYL3600, EBECRYL3700, EBECRYL3701, EBECRYL3702, EBECRYL3703, EBECRYL3800, EBECRYL6040, EBECRYL6040, All manufactured by Manufacturing), EA-1010, EA-1020, EA-5323, EA-5520, EA-CHD, EMA-1020 (all manufactured by Shinnakamura Chemical Industry Co., Ltd.), Epoxy Ester M-600A, Epoxy Ester 40EM, Epoxy Ester 70PA , Epoxy Ester 200PA, Epoxy Ester 80MFA, Epoxy Ester 3002M, Epoxy Ester 3002A, Epoxy Ester 1600A, Epoxy Ester 3000M, Epoxy Ester 3000A, Epoxy Ester 200EA, Epoxy Ester 400EA (all manufactured by Kyoeisha Chemical Co., Ltd.), Denacol Aerylate DA -141, Denacol Acrylate DA-314, Denacol Acrylate DA-911 (all manufactured by Nagase ChemteX), etc.

As a (meth)acrylic acid amine ester obtained by reacting a (meth)acrylic acid derivative having a hydroxyl group with the above-mentioned isocyanate compound, for example, a (meth)acrylic acid derivative having a hydroxyl group can be made 2 equivalents and having It is obtained by reacting 1 equivalent of an isocyanate compound of two isocyanate groups in the presence of a catalytic amount of a tin-based compound.

As the isocyanate compound used as the raw material of the (meth)acrylate amine ester, for example, isophorone diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, hexamethylene 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, thiophosphoric acid tris(isocyanatophenyl) ester, tetramethylxylylene diisocyanate, 1, 6,11-Undecane triisocyanate, etc.

In addition, as the isocyanate compound used as the raw material of the aforementioned (meth)acrylate amine ester, for example, ethylene glycol, propylene glycol, glycerin, sorbitol, trimethylolpropane, carbonate diol, and polyether diol can also be used. , Polyester diol, polycaprolactone diol and other polyols reacted with excess isocyanate compounds to obtain chain-extended isocyanate compounds.

Examples of (meth)acrylic acid derivatives having hydroxyl groups used as raw materials for the above-mentioned (meth)acrylic acid amine esters include: 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, Hydroxyalkyl mono(meth)acrylates such as 2-hydroxybutyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate or ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butane Mono(meth)acrylate of glycol, 1,4-butanediol, polyethylene glycol, or mono(meth)acrylate such as trimethylolethane, trimethylolpropane, glycerin, etc. Epoxy (meth)acrylates such as acrylate, di(meth)acrylate, or bisphenol A epoxy acrylate, etc.

Examples of commercially available amine (meth)acrylate esters include: M-1100, M-1200, M-1210, M-1600 (all manufactured by Toagosei Co., Ltd.), EBECRYL210, EBECRYL220, EBECRYL230, EBECRYL270 , EBECRYL1290, EBECRYL2220, EBECRYL4827, EBECRYL4842, EBECRYL4858, EBECRYL5129, EBECRYL6700, EBECRYL8402, EBECRYL8803, EBECRYL8804, EBECRYL8807, EBECRYL9260 (all manufactured by Daicel-Art Resin UN-330, Art Resin UN-330, Art Resin UN-330) 1200TPK, Art Resin UN-1255, Art Resin UN-3320HB, Art Resin UN-7100, Art Resin UN-9000A, Art Resin UN-9000H (all manufactured by Nejo Kogyo), U-2HA, U-2PHA, U- 3HA, U-4HA, U-6H, U-6HA, U-6LPA, U-10H, U-15HA, U-108, U-108A, U-122A, U-122P, U-324A, U-340A, U-340P, U-1084A, U-2061BA, UA-340P, UA-4000, UA-4100, UA-4200, UA-4400, UA-5201P, UA-7100, UA-7200, UA-W2A (all made by Shin Nakamura Chemical Industry Co., Ltd.), AH-600, AI-600, AT-600, UA-101I, UA-101T, UA-306H, UA-306I, UA-306T (all manufactured by Kyoeisha Chemical Co., Ltd.), etc. .

As said monofunctional epoxy compound, a partial (meth)acrylic modified epoxy resin etc. are mentioned, for example.

Furthermore, in this specification, the above-mentioned partially (meth)acrylic modified epoxy resin refers to a compound having one epoxy group and more than one (meth)acryloyl group in one molecule, for example It can be obtained by reacting a part of the epoxy group of the above-mentioned polyfunctional epoxy compound with (meth)acrylic acid.

From the viewpoint of suppressing liquid crystal contamination, the above-mentioned other curable resin is preferably one having hydrogen bonding units such _{as -OH group, -NH- group, and -NH 2 group.}

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

As the above-mentioned polymerization initiator, a radical polymerization initiator is preferably used.

Examples of the radical polymerization initiator include thermal radical polymerization initiators that generate radicals by heating, photo-radical polymerization initiators that generate radicals by light irradiation, and the like.

(thioxanthone)等。 Examples of the aforementioned photoradical polymerization initiator include benzophenone-based compounds, acetophenone-based compounds, phosphine oxide-based compounds, titanocene-based compounds, oxime ester-based compounds, benzoin ether-based compounds, 9-oxysulfur

(thioxanthone) and so on.

Examples of commercially available photo radical polymerization initiators include IRGACURE184, IRGACURE369, IRGACURE379, IRGACURE651, IRGACURE819, IRGACURE907, IRGACURE2959, IRGACURE OXE01, Lucirin TPO (all manufactured by BASF), benzoin methyl ether, Benzoin ethyl ether, benzoin isopropyl ether (all manufactured by Tokyo Chemical Industry Co., Ltd.), KR-02 (manufactured by Light Chemical Co., Ltd.), and the like.

Examples of the thermal radical polymerization initiator include those composed of azo compounds, organic peroxides, and the like. Among them, a polymer azo initiator composed of a polymer azo compound is preferred.

Furthermore, in this specification, the so-called polymer azo initiator refers to a compound having an azo group and generating radicals capable of hardening the (meth)acryloyl group by heat. The number average molecular weight of the compound is 300 or more .

The preferred lower limit of the number average molecular weight of the polymer azo initiator is 1,000, and the preferred upper limit is 300,000. By setting the number average molecular weight of the polymer azo initiator to this range, it is possible to prevent adverse effects on the liquid crystal and easily mix with the curable resin. The lower limit of the number average molecular weight of the above-mentioned polymer azo initiator is more preferably 5,000, the upper limit is more preferably 100,000, the lower limit is more preferably 10,000, and the upper limit is more preferably 90,000.

In addition, in this specification, the said number average molecular weight is the value calculated|required by the polystyrene conversion measured by gel permeation chromatography (GPC). As a column for measuring the "number average molecular weight based on polystyrene conversion" by GPC, for example, Shodex LF-804 (manufactured by Showa Denko) can be cited.

Examples of the above-mentioned polymer azo initiator include those having a structure in which a plurality of units such as polyalkylene oxide or polydimethylsiloxane are bonded via an azo group.

The polymer azo initiator having a structure in which a plurality of units such as polyalkylene oxide are bonded via an azo group is preferably one having a polyethylene oxide structure. As such a polymer azo initiator, for example, a condensation polymer of 4,4'-azobis(4-cyanovaleric acid) and polyalkylene glycol or 4,4'-azobis (4-cyanovaleric acid) and polydimethylsiloxane having a terminal amine group, etc., specifically, for example: VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS-1001 (all manufactured by Wako Pure Chemical Industries, Ltd.), etc. In addition, examples of azo compounds that are not polymers include V-65 and V-501 (both manufactured by Wako Pure Chemical Industries, Ltd.).

Examples of the above-mentioned organic peroxide include ketone peroxide, peroxyketal, hydrogen peroxide, dialkyl peroxide, peroxyester, diacyl peroxide, and peroxydicarbonate.

With respect to 100 parts by weight of the curable resin, the preferred lower limit of the content of the polymerization initiator is 0.1 parts by weight, and the preferred upper limit is 30 parts by weight. By setting the content of the polymerization initiator in this range, the obtained sealing compound for liquid crystal display elements is more excellent in curability while maintaining excellent storage stability. The lower limit of the content of the polymerization initiator is more preferably 1 part by weight, the upper limit is more preferably 10 parts by weight, and the upper limit is more preferably 5 parts by weight.

As said thermosetting agent, organic acid hydrazine, imidazole derivatives, amine compounds, polyphenol compounds, acid anhydrides, etc. are mentioned, for example. Among them, it is preferable to use a solid organic acid hydrazine.

Examples of the solid organic acid hydrazine include: 1,3-bis(hydrazinocarbonylethyl-5-isopropylhydantoin), sebacic hydrazine, isophthalic acid hydrazine, and hexamethylene As commercially available products such as hydrazine and malondihydrazine, for example, SDH, ADH (manufactured by Otsuka Chemical Co., Ltd.), MDH (manufactured by Japan Finechem Co., Ltd.), Amicure VDH, Amicure VDH-J, and Amicure UDH (all manufactured by Ajinomoto Fine-Techno Corporation) and so on.

With respect to 100 parts by weight of the curable resin, the preferred lower limit of the content of the thermosetting agent is 1 part by weight, and the preferred upper limit is 50 parts by weight. By making the content of the said thermosetting agent into this range, the sealing compound for liquid crystal display elements obtained becomes one which is more excellent in curability while maintaining excellent coating property or storage stability. The more preferable upper limit of the content of the thermal hardening agent is 30 parts by weight.

From the viewpoint of improving storage stability, etc., the sealing compound for liquid crystal display elements of the present invention preferably contains a polymerization inhibitor.

-2,4,6-(1H,3H,5H)三酮、對苯二酚、對甲氧基苯酚等。 As the polymerization inhibitor, for example, 2,6-di-tert-butyl cresol, butylated hydroxyanisole, 2,6-di-tert-butyl-4-ethylphenol, β-(3,5 -Di-tertiary butyl-4-hydroxyphenyl) stearyl propionate, 2,2'-methylene bis(4-methyl-6-tertiary butylphenol), 2,2'-ethylene Methyl bis (4-ethyl-6-tertiary butyl phenol), 4,4'-thiobis (3-methyl-6-tertiary butyl phenol), 4,4-butylene bis (3 -Methyl-6-tert-butylphenol), 3,9-bis(1,1-dimethyl-2-(β-(3-tert-butyl-4-hydroxy-5-methylphenyl) )Propyloxy)ethyl)-2,4,8,10-tetraoxaspiro(5,5)undecane, tetrakis(methylene-3-(3',5'-di-tertiary butyl) -4'-hydroxyphenyl) propionate) methane, 1,3,5-tris(3',5'-di-tert-butyl-4'-hydroxybenzyl)-symmetric three

-2,4,6-(1H,3H,5H) triketone, hydroquinone, p-methoxyphenol, etc.

With respect to 100 parts by weight of the curable resin, the preferable lower limit of the content of the polymerization inhibitor is 0.005 parts by weight, and the preferable upper limit is 0.2 parts by weight. By setting the content of the polymerization inhibitor within this range, it is possible to further exhibit effects such as improvement in storage stability while maintaining the excellent hardening properties of the obtained sealing compound for liquid crystal display elements. A more preferable lower limit of the content of the polymerization inhibitor is 0.007 parts by weight, and a more preferable upper limit is 0.18 parts by weight.

In order to increase the viscosity, further increase the adhesion due to the stress dispersion effect, improve the linear expansion rate, and increase the moisture resistance of the cured product, the sealing compound for liquid crystal display elements of the present invention preferably contains a filler.

Examples of the above-mentioned filler include: silica, talc, glass beads, asbestos, gypsum, diatomaceous earth, bentonite, bentonite, montmorillonite, sericite, activated clay, alumina, zinc oxide, iron oxide , Magnesium oxide, tin oxide, titanium oxide, calcium carbonate, magnesium carbonate, magnesium hydroxide, aluminum hydroxide, aluminum nitride, silicon nitride, barium sulfate, calcium silicate and other inorganic fillers or polyester particles, polyurethane particles, Organic fillers such as ethylene polymer particles and acrylic polymer particles.

In 100 parts by weight of the sealing compound for liquid crystal display elements of the present invention, the lower limit of the filler content is preferably 10 parts by weight, and the upper limit is preferably 70 parts by weight. By setting the content of the filler in this range, it is possible to suppress deterioration of coatability and the like, and to further exhibit the effects of improving adhesiveness and the like. The more preferable limit of the content of the above filler is 20 parts by weight, and the more preferable upper limit is 60 parts by weight.

It is preferable that the sealing compound for liquid crystal display elements of this invention contains a silane coupling agent in order to improve adhesiveness further. The above-mentioned silane coupling agent mainly has a function as an adhesive auxiliary agent for bonding the sealant to the substrate and the like well.

As the silane coupling agent, for example, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, etc. are preferably used.

In 100 parts by weight of the sealing compound for liquid crystal display elements of the present invention, a preferable lower limit of the content of the silane coupling agent is 0.1 parts by weight, and a preferable upper limit is 10 parts by weight. By setting the content of the silane coupling agent in this range, the occurrence of liquid crystal contamination can be suppressed and the effect of improving adhesiveness can be more exerted. The lower limit of the content of the silane coupling agent is more preferably 0.3 parts by weight, and the upper limit is more preferably 5 parts by weight.

The sealing compound for liquid crystal display elements of this invention may contain a light-shielding agent. By containing the said light-shielding agent, the sealing compound for liquid crystal display elements of this invention can be used suitably as a light-shielding sealing compound.

Examples of the light-shielding agent include iron oxide, titanium black, aniline black, cyanine black, fullerene, carbon black, and resin-coated carbon black. Among them, titanium black is preferred.

The aforementioned titanium black is a substance that has an increased light transmittance in the vicinity of the ultraviolet region, especially light with a wavelength of 370 to 450 nm, compared to the average light transmittance of light with a wavelength of 300 to 800 nm. That is, the above-mentioned titanium black is a light-shielding agent having the property that it provides light-shielding properties to the sealant for liquid crystal display elements of the present invention by sufficiently shielding light of wavelengths in the visible light region, and on the other hand, makes it close to the ultraviolet region. Light of wavelength penetrates. As the light-shielding agent contained in the sealing compound for liquid crystal display elements of the present invention, a substance with high insulation is preferable, and as a light-shielding agent with high insulation, titanium black is also preferable.

The above-mentioned titanium black will have full effect even if it is not surface-treated. It can also be used if the surface is treated with organic ingredients such as coupling agent, or with silicon oxide, titanium oxide, germanium oxide, aluminum oxide, zirconium oxide, or magnesium oxide. The surface-treated titanium black is coated with other inorganic components. Among them, in terms of being able to further improve the insulation properties, those treated with organic components are preferred.

In addition, the liquid crystal display element manufactured using the sealant for liquid crystal display elements of the present invention containing the titanium black as a light-shielding agent has sufficient light-shielding properties, and therefore can achieve no light leakage, high contrast, and excellent images. Image display quality liquid crystal display element.

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

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.

In addition, the preferred lower limit of the volume resistance of the above-mentioned titanium black is 0.5Ω. cm, the preferred upper limit is 3Ω. cm, the lower limit is more preferably 1Ω. cm, the more preferable upper limit is 2.5Ω. cm.

The primary particle size of the light-shielding agent is not particularly limited as long as it is less than the distance between the substrates of the liquid crystal display element. The preferred lower limit is 1 nm, and the preferred upper limit is 5 μm. When the primary particle diameter of the said light-shielding agent is this range, the viscosity or thixotropy of the sealing compound for liquid crystal display elements obtained does not increase significantly, and it becomes one which is more excellent in coatability. The lower limit of the primary particle size of the sunscreen is more preferably 5 nm, the upper limit is more preferably 200 nm, the lower limit is still more preferably 10 nm, and the upper limit is more preferably 100 nm.

In addition, the primary particle size of the above-mentioned sunscreen can be measured using a particle size distribution meter (for example, "NICOMP380ZLS" manufactured by PARTICLE SIZING SYSTEMS).

In 100 parts by weight of the sealing compound for liquid crystal display elements of the present invention, a preferable lower limit of the content of the light-shielding agent is 5 parts by weight, and a preferable upper limit is 80 parts by weight. By setting the content of the above-mentioned light-shielding agent in this range, the effect of improving light-shielding properties can be exhibited without deteriorating the adhesiveness, the strength after curing, and the drawing properties of the obtained sealing compound for liquid crystal display elements. The lower limit of the content of the sunscreen is more preferably 10 parts by weight, the upper limit is more preferably 70 parts by weight, the lower limit is still more preferably 30 parts by weight, and the upper limit is more preferably 60 parts by weight.

The sealing compound for liquid crystal display elements of the present invention may further contain additives such as a stress reliever, a reactive diluent, a thixotropic agent, a spacer, a hardening accelerator, a defoamer, and a leveling agent, if necessary.

As a method of manufacturing the sealant for liquid crystal display elements of the present invention, for example, the use of mixers such as homogeneous dispersers, homomixers, universal mixers, planetary mixers, kneaders, and three-roll mills can be used to reduce the curability. The method of mixing resin, polymerization initiator and/or thermosetting agent and optionally silane coupling agent and other additives.

Regarding the sealing compound for liquid crystal display elements of the present invention, the lower limit of the adhesive strength of the cured product to the glass substrate is 290 N/cm ² . By making the above-mentioned adhesive strength 290 N/cm ² or more, the obtained liquid crystal display element has excellent impact resistance. The preferred lower limit of the adhesive strength is 310 N/cm ² , and the more preferred lower limit is 330 N/cm ² .

The higher the bonding strength, the better, and there is no upper limit, but the actual upper limit is 400 N/cm ² .

Furthermore, the adhesive strength of the above-mentioned cured product to the glass substrate can be measured by the following method.

First, apply the sealant for liquid crystal display elements on a glass substrate, overlay another glass substrate on it, spread the sealant for liquid crystal display elements, irradiate 100mW/cm ² of ultraviolet rays for 30 seconds, and then heat at 120°C For 1 hour, a subsequent test piece was produced by this. Next, with respect to the obtained adhesive test piece, the adhesive strength of the hardened product to the glass substrate can be measured by using a tensiometer.

The sealing compound for liquid crystal display elements of the present invention is suitable for curing at high temperatures, and is preferably used for curing at 100°C or higher, and more preferably for curing at 110°C or higher.

By blending conductive fine particles in the sealing compound for liquid crystal display elements of the present invention, a vertical conduction material can be produced. Moreover, the top and bottom conduction material containing the sealing compound for liquid crystal display elements of this invention and conductive microparticles|fine-particles is also one of this invention.

As the conductive fine particles, metal balls, those having a conductive metal layer formed on the surface of the resin fine particles, or the like can be used. Among them, those with a conductive metal layer formed on the surface of the resin fine particles are preferable because of the excellent elasticity of the resin fine particles, which can be electrically connected without damaging the transparent substrate or the like.

Moreover, the liquid crystal display element which uses the sealing compound for liquid crystal display elements of this invention or the top and bottom conduction material of this invention is also one of this invention.

The sealing compound for a liquid crystal display element of the present invention suppresses the generation of afterimages and the like even when the aperture ratio of the sealing compound in the obtained liquid crystal display element is low, making the liquid crystal display element excellent in display performance. Therefore, it can be suitably used for a liquid crystal display element with a low aperture ratio of a sealant. Specifically, the sealing compound for liquid crystal display elements of the present invention is suitable for liquid crystal display elements having an aperture ratio of 50% or less of the sealing compound, and more suitable for liquid crystal display elements having an aperture ratio of 30% or less of the sealing compound.

Furthermore, the above-mentioned "opening ratio of the sealant" refers to the ratio of the part of the sealant that is not covered by wiring, etc., which can be measured by observing the shape of the metal wiring arranged on the upper part of the sealant with an optical microscope .

The sealing compound for liquid crystal display elements of this invention can be used suitably for manufacture of the liquid crystal display element by a liquid crystal dropping method.

As a method of manufacturing the liquid crystal display element of the present invention by the liquid crystal dropping method, specifically, for example, a method having the following steps: by screen printing, dispenser coating, etc., the liquid crystal display element of the present invention The sealant is equivalent to forming a frame-shaped seal pattern on the substrate; in the uncured state of the sealant for liquid crystal display elements of the present invention, small drops of liquid crystal are applied to the entire surface of the frame of the transparent substrate and overlap immediately Another substrate; the sealing pattern of the sealant for liquid crystal display elements of the present invention is partially irradiated with light such as ultraviolet rays to temporarily harden the sealant; and the temporarily hardened sealant is heated to be fully hardened.

According to the present invention, it is possible to provide a sealing compound for a liquid crystal display element which has excellent adhesiveness, low liquid crystal contamination, and can obtain a liquid crystal display element with excellent display performance. In addition, according to the present invention, it is possible to provide an upper and lower conduction material and a liquid crystal display element using this sealing compound for liquid crystal display elements.

Hereinafter, the present invention will be explained in more detail with examples, but the present invention is not limited to these examples.

(Production of curable resin A)

116 parts by weight of 2-hydroxyethyl acrylate, 114 parts by weight of β-propiolactone, and 0.3 parts by weight of hydroquinone as a polymerization inhibitor were added to the reaction flask, stirred at 90°C for 5 hours using a heating mantle, and then added 148 parts by weight of phthalic anhydride was further stirred for 5 hours. Next, 170 parts by weight of bisphenol A diglycidyl ether was added to the obtained reactant, and the mixture was stirred at 90° C. for 5 hours, thereby obtaining curable resin A.

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin A is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The group represented (b=2, c=0, d=0), R ³ is a structure derived from phthalic anhydride represented by the following formula (3), and R ⁴ is represented by the following formula (4) It is derived from the structure of bisphenol A diglycidyl ether, X is the ring-opening structure of β-propiolactone represented by the following formula (5), n=2, a=2).

In formula (3), * represents the bonding position.

In formula (4), * represents the bonding position.

In formula (5), * represents the bonding position.

(Production of curable resin B)

Except that the blending amount of β-propiolactone was changed to 360 parts by weight, curable resin B was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin B is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The base represented by (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), R ⁴ is derived from the above formula (4) The structure of bisphenol A diglycidyl ether, X is the ring-opening structure of β-propiolactone represented by the above formula (5), n=5, a=2).

(Production of curable resin C)

Except for blending 200 parts by weight of γ-valerolactone instead of 114 parts by weight of β-propiolactone, curable resin C was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin C is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The base represented by (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), and R ⁴ is derived from the above formula (4) In the structure of bisphenol A diglycidyl ether, X is the ring-opening structure of γ-valerolactone represented by the following formula (6), n=2, a=2).

In formula (6), * represents the bonding position.

(Production of curable resin D)

Except that 500 parts by weight of γ-valerolactone was blended instead of 114 parts by weight of β-propiolactone, curable resin D was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin D is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The base represented by (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), and R ⁴ is derived from the above formula (4) The structure of bisphenol A diglycidyl ether, X is the ring-opening structure of γ-valerolactone represented by the above formula (6), n=5, a=2).

(Production of curable resin E)

Except that 114 parts by weight of ε-caprolactone was blended instead of 114 parts by weight of β-propiolactone, curable resin E was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin E is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The base represented by (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), and R ⁴ is derived from the above formula (4) In the structure of bisphenol A diglycidyl ether, X is the ring-opening structure of ε-caprolactone represented by the following formula (7), n=1, a=2).

In formula (7), * represents the bonding position.

(Production of curable resin F)

Except that 228 parts by weight of ε-caprolactone was blended instead of 114 parts by weight of β-propiolactone, curable resin F was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin F is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The base represented by (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), and R ⁴ is derived from the above formula (4) The structure of bisphenol A diglycidyl ether, X is the ring-opening structure of ε-caprolactone represented by the above formula (7), n=2, a=2).

(Production of curable resin G)

Except that 342 parts by weight of ε-caprolactone was blended instead of 114 parts by weight of β-propiolactone, curable resin G was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin G is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The base represented by (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), and R ⁴ is derived from the above formula (4) The structure of bisphenol A diglycidyl ether, X is the ring-opening structure of ε-caprolactone represented by the above formula (7), n=3, a=2).

(Production of curable resin H)

Except that 456 parts by weight of ε-caprolactone was blended instead of 114 parts by weight of β-propiolactone, curable resin H was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin H is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The base represented by (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), and R ⁴ is derived from the above formula (4) The structure of bisphenol A diglycidyl ether, X is the ring-opening structure of ε-caprolactone represented by the above formula (7), n=4, a=2).

(Production of curable resin I)

Except that 570 parts by weight of ε-caprolactone was blended instead of 114 parts by weight of β-propiolactone, curable resin I was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin I is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The base represented by (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), and R ⁴ is derived from the above formula (4) The structure of bisphenol A diglycidyl ether, X is the ring-opening structure of ε-caprolactone represented by the above formula (7), n=5, a=2).

(Production of curable resin J)

Except that 684 parts by weight of ε-caprolactone was blended instead of 114 parts by weight of β-propiolactone, curable resin J was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin J is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The base represented by (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), and R ⁴ is derived from the above formula (4) The structure of bisphenol A diglycidyl ether, X is the ring-opening structure of ε-caprolactone represented by the above formula (7), n=6, a=2).

(Production of curable resin K)

Except for blending 256 parts by weight of γ-heptanolactone instead of 114 parts by weight of β-propiolactone, curable resin K was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin K is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The base represented by (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), and R ⁴ is derived from the above formula (4) In the structure of bisphenol A diglycidyl ether, X is the ring-opening structure of γ-heptanolide represented by the following formula (8), n=2, a=2).

In formula (8), * represents the bonding position.

(Production of curable resin L)

Except that 640 parts by weight of γ-heptanolactone was blended instead of 114 parts by weight of β-propiolactone, curable resin L was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin L is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The base represented by (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), and R ⁴ is derived from the above formula (4) The structure of bisphenol A diglycidyl ether, X is the ring-opening structure of γ-heptanolide represented by the above formula (8), n=5, a=2).

(Production of curable resin M)

Blended with 342 parts by weight of ε-caprolactone instead of 114 parts by weight of β-propiolactone, and blended with 230 parts by weight of tris(p-hydroxyphenyl)methane diglycidyl ether instead of 170 parts by weight of bisphenol A diglycidyl ether Except for this, the curable resin M was obtained in the same manner as in the above-mentioned "(Production of curable resin A)".

By ¹ H-NMR, ¹³ C-NMR, and FT-IR analysis, it was confirmed that the curable resin M is the compound represented by the above formula (1) (R ¹ is a hydrogen atom, and R ² is the above formula (2-2) The represented group (b=2, c=0, d=0), R ³ is the structure derived from phthalic anhydride represented by the above formula (3), and R ⁴ is the structure represented by the following formula (9) From the structure of tris(p-hydroxyphenyl)methane diglycidyl ether, X is the ring-opening structure of ε-caprolactone represented by the above formula (7), n=3, a=2).

In formula (9), * represents the bonding position.

(Production of part of acrylic modified bisphenol F epoxy resin)

312 parts by weight of bisphenol F diglycidyl ether was dissolved in 600 mL of toluene, and 0.2 g of triphenylphosphine was added to the solution to prepare a uniform solution. In the obtained solution, 72 parts by weight of acrylic acid was added dropwise over 2 hours under reflux stirring, and then reflux stirring was further performed for 6 hours. Then, toluene is removed, thereby obtaining a partially acrylic modified bisphenol F epoxy resin represented by the following formula (10).

(Examples 1 to 17, Comparative Examples 1 to 5)

In accordance with the blending ratios described in Tables 1 to 3, the materials were stirred using a planetary stirring device (“Defoaming Nintaro” manufactured by Thinky), and then uniformly mixed using a ceramic three-roll mill to obtain the examples. 1-17. The sealing compound for liquid crystal display elements of Comparative Examples 1 to 5.

<evaluation>

The following evaluations were performed on each of the sealing compounds for liquid crystal display elements obtained in the examples and comparative examples. The results are shown in Tables 1 to 3.

(Storage stability)

Put each sealant for liquid crystal display elements obtained in the Examples and Comparative Examples into a syringe, and use a vacuum defoaming device (manufactured by Thinky, "ARV-200") to defoam in vacuum at 1500 rpm and 3 torr for 10 minutes. Place it in an environment with a temperature of 23°C and a humidity of 50%RH for 2 weeks, and then use a spatula to take out a small amount and manually apply it on the glass substrate to investigate whether the sealant has gelled.

The ones that are not gelled and can be easily applied to the glass substrate are set to "○", the ones that are gelled and the coatability deteriorates are set to "△", the ones that cannot be coated are set to "×", and the The storage stability is evaluated.

(Adhesion)

Using a planetary stirring device, polymer beads with an average particle diameter of 5 μm (manufactured by Sekisui Chemical Industry Co., Ltd., "Micropearl SP") relative to 100 parts by weight of each liquid crystal display element sealing compound obtained in the Examples and Comparative Examples Disperse 3 parts by weight to make a uniform liquid. Take a very small amount of the obtained liquid and place it on the center of a glass substrate (20mm×50mm×1.1mmt), and superimpose the same type of glass substrate on it to spread the sealant for liquid crystal display elements. In this state, 100 mW/cm ² ultraviolet rays were irradiated for 30 seconds, and then heated at 120° C. for 1 hour to obtain an adhesive test piece.

The adhesive strength of the obtained adhesive test piece was measured using a tensiometer.

(Display performance of liquid crystal display element (after-image prevention))

Put 0.5 g of liquid crystal ("JC-5001LA" manufactured by Chisso) into a sample bottle, add 0.1 g of each liquid crystal dropping method sealant obtained in the examples and comparative examples and shake, then heat at 120°C for 1 hour, and then Return to room temperature (25°C).

On the alignment film of a glass substrate with a transparent electrode and an alignment film (manufactured by Nissan Chemical Co., "SE7492"), each liquid crystal dropping method obtained in the examples and comparative examples was coated with a dispenser in a square frame manner Use sealant. Then, drop the tiny drops of liquid crystal taken out from the sample bottle onto the entire surface of the frame on the substrate, and overlap another glass substrate in a vacuum. The vacuum was released, 100 mW/cm ² ultraviolet rays were irradiated for 30 seconds, and then heated at 120° C. for 1 hour to harden the sealant to obtain a liquid crystal display element (the opening ratio of the sealant was 20%).

With regard to the obtained liquid crystal display element, the occurrence of afterimages when an AC voltage of 1.5V was applied on one side and a DC voltage of 1V was applied on the other side was visually confirmed. As a result, the case where the afterimage is not confirmed at all is set to "○", the case where a little afterimage is confirmed is set to "△", and the case where a serious afterimage is confirmed is set to "×", and the LCD display The display performance (after-image prevention) of the device was evaluated.

(Display performance of liquid crystal display element (low liquid crystal pollution))

On the alignment film of a glass substrate with a transparent electrode and an alignment film (manufactured by Nissan Chemical Co., "SE7492"), the liquid crystal drops obtained in the Examples and Comparative Examples were coated with a dispenser in a square frame manner. French sealant. Then, a small drop of liquid crystal (manufactured by Chisso, "JC-5001LA") was dripped and coated on the entire surface of the frame on the substrate, and another glass substrate was superimposed in a vacuum. Release the vacuum, cover the display area with a mask, irradiate 100mW/cm ² of ultraviolet rays for 30 seconds, and then heat at 120°C for 1 hour to harden the sealant to obtain a liquid crystal display element (the opening ratio of the sealant is 20 %). With respect to the obtained liquid crystal display element, the periphery of the sealing compound of the display part was confirmed using a polarizing microscope. As a result, the case where the display unevenness is not confirmed at all is set to "○", the case where a little display unevenness is confirmed is set to "△", and the case where serious display unevenness is confirmed is set to "×", and The display performance (low liquid crystal contamination) of the liquid crystal display element was evaluated.

(Impact resistance of liquid crystal display element)

Regarding the sealants for liquid crystal display elements obtained in the Examples and Comparative Examples, the liquid crystal display elements were made into 10 liquid crystal cells in the same manner as the above "(Display performance of liquid crystal display elements (low liquid crystal contamination))" .

Perform a drop test in which each liquid crystal display element is dropped from a height of 2m. After the drop test, set the condition that all the liquid crystal cells have no liquid crystal leakage due to peeling or cracking, set to "○", and set 1 or more liquid crystal cells In addition, the case where the liquid crystal display element with less than 9 liquid crystal cells had liquid crystal leakage was set to "△", and the case where all the liquid crystal display elements had liquid crystal leakage was set to "×", and the impact resistance of the liquid crystal display element was evaluated.

[Industrial availability]

According to the present invention, it is possible to provide a sealing compound for a liquid crystal display element which has excellent adhesiveness, low liquid crystal contamination, and can obtain a liquid crystal display element with excellent display performance. In addition, according to the present invention, it is possible to provide an upper and lower conduction material and a liquid crystal display element using this sealing compound for liquid crystal display elements.

Claims (6)

A sealing compound for liquid crystal display elements, which contains a curable resin, a polymerization initiator and/or a thermosetting agent, and is characterized in that the curable resin contains a compound represented by the following formula (1), and one molecule has Compounds with 2 or more epoxy groups, in 100 parts by weight of the curable resin, the content of compounds with 2 or more epoxy groups in one molecule is 5 parts by weight or more and 25 parts by weight or less, and the cured product is bonded to the glass substrate The strength is above 290N/cm ² ,

In formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a group represented by the following formula (2-1) or (2-2), R ³ represents a structure derived from an acid anhydride, and R ⁴ represents a ring The structure of the oxygen compound, X represents the ring-opening structure of the lactone, n represents an integer from 1 to 6, and a represents an integer from 1 to 4.

In formula (2-1), * represents the bonding position, in formula (2-2), b represents an integer from 0 to 8, c represents an integer from 0 to 3, d represents an integer from 0 to 8, and e represents 0 to An integer of 8, any one of b, c, d is 1 or more, and * represents the bonding position. As for the sealing compound for liquid crystal display elements of the first item of the patent application, the content of the compound represented by formula (1) in 100 parts by weight of the curable resin is 5-50 parts by weight. For example, the sealing compound for liquid crystal display elements of the first or second item of the scope of patent application contains a polymerization inhibitor. For example, the sealing compound for liquid crystal display elements of the 1st or 2nd item of the scope of patent application contains a light-shielding agent. An up-and-down conduction material containing the sealant for liquid crystal display elements of the 1, 2, 3, or 4 scope of the patent application and conductive fine particles. A liquid crystal display element is formed by using the sealant for liquid crystal display elements of item 1, 2, 3, or 4 in the scope of patent application or the upper and lower conductive materials of item 5 in the scope of patent application.