TWI885161B - Sealant for liquid crystal display element, upper and lower conductive material and liquid crystal display element - Google Patents

Abstract

The purpose of the present invention is to provide a novel dihydrazide compound. In addition, the purpose of the present invention is to provide a curable resin composition containing the dihydrazide compound and having excellent preservation stability, curability and adhesion, and a sealant for liquid crystal display elements, a top and bottom conductive material and a liquid crystal display element having excellent low liquid crystal contamination using the curable resin composition. The present invention is a dihydrazide compound having a divalent aliphatic alkyl group, wherein one or more hydrogen atoms of the divalent aliphatic alkyl group are substituted by a group containing an aromatic ring.

Description

Sealant for liquid crystal display element, upper and lower conductive material and liquid crystal display element

The present invention relates to a novel dihydrazide compound. In addition, the present invention relates to a curable resin composition containing the dihydrazide compound and having excellent storage stability, curability and adhesion, and a sealant for liquid crystal display elements, a vertical conductive material and a liquid crystal display element having excellent low liquid crystal contamination properties made using the curable resin composition.

In recent years, as a manufacturing method for liquid crystal display elements such as liquid crystal display units, from the perspective of shortening the takt time and optimizing the amount of liquid crystal used, a liquid crystal dripping method called a dripping method using a sealant as disclosed in Patent Documents 1 and 2 has been used.

In the dripping method, first, a frame-shaped sealing pattern is formed on one of two substrates with electrodes by dispensing glue. Then, before the sealant is cured, tiny droplets of liquid crystal are added to the frame of the sealing pattern, and the sealant is cured after being overlapped with the other substrate under vacuum, thereby making a liquid crystal display element. Currently, the dripping method is the mainstream method for manufacturing liquid crystal display elements.

In the modern era when mobile devices with LCD panels such as mobile phones and portable game consoles are widely used, miniaturization of devices is the most demanding topic. As a method for miniaturizing devices, narrowing the edge of the LCD display part can be cited. For example, the industry has carried out operations to arrange the position of the sealing part under the black matrix (hereinafter also referred to as narrow edge design).

Prior art literature

Patent Literature

Patent document 1: Japanese Patent Publication No. 2001-133794

Patent document 2: International Publication No. 02/092718

In the narrow edge design, the sealant is placed directly below the black matrix, so when the dripping method is performed, the light irradiated during the photocuring of the sealant will be blocked, and the light will have difficulty reaching the inside of the sealant, and the previous curing of the sealant will become insufficient. When the curing of the sealant becomes insufficient as described above, there is a problem that the uncured sealant components dissolve in the liquid crystal and become easy to cause liquid crystal contamination. In particular, in recent years, with the high polarization of liquid crystals, even when using sealants that have no problems before, liquid crystal contamination may sometimes occur, and the sealant is required to have further low liquid crystal contamination.

When it is difficult to cure the sealant by light, curing it by heating is considered. As a method for curing the sealant by heating, a thermosetting agent is mixed into the sealant. However, when a highly reactive thermosetting agent is used to improve the curability and adhesion of the sealant, the storage stability of the obtained sealant may become poor or liquid crystal contamination may occur.

The purpose of the present invention is to provide a novel dihydrazide compound. In addition, the purpose of the present invention is to provide a curable resin composition containing the dihydrazide compound and having excellent storage stability, curability and adhesion, and a sealant for liquid crystal display elements, upper and lower conductive materials and liquid crystal display elements with excellent low liquid crystal contamination properties made using the curable resin composition.

The present invention is a dihydrazide compound having a divalent aliphatic alkyl group, wherein one or more hydrogen atoms of the divalent aliphatic alkyl group are substituted by a group containing an aromatic ring.

The present invention is described in detail below.

The inventors of the present invention have found that by using a dihydrazide compound having a specific structure as a thermosetting agent, a curable resin composition having excellent storage stability, curability and adhesion can be obtained. Furthermore, the sealant for liquid crystal display elements formed using the curable resin composition also has excellent low liquid crystal contamination properties, thereby completing the present invention.

The dihydrazide compound of the present invention has a divalent aliphatic alkyl group, wherein one or more hydrogen atoms of the divalent aliphatic alkyl group are substituted by a group containing an aromatic ring. By using the dihydrazide compound of the present invention having such a structure as a thermosetting agent, a curable resin composition having excellent storage stability, curability and adhesion can be obtained. In addition, the dihydrazide compound of the present invention has a low solubility in highly polar liquid crystals, so the low liquid crystal contamination property of the sealant for liquid crystal display elements using the curable resin composition will also be further improved.

Examples of the above-mentioned groups containing an aromatic ring include phenyl, tolyl, benzyl, chlorophenyl, bromophenyl, aminophenyl, nitrophenyl, pyridyl, biphenyl, methylbiphenyl, naphthyl, anthracenyl, etc.

Examples of the above-mentioned aliphatic hydrocarbon groups include methylene, ethyl, propyl, butyl, hexyl, etc.

The dihydrazide compound of the present invention is preferably represented by the following formula (1) in terms of both good reactivity and storage stability.

Examples of the compound represented by the following formula (1) include phenylsuccinic acid dihydrazide (a compound represented by the following formula (2)), benzylmalonic acid dihydrazide, phenylmalonic acid dihydrazide, etc.

Among them, the dihydrazide compound of the present invention is preferably represented by the following formula (2) in terms of reducing the stereo hindrance of liquid crystal contamination.

In formula (1), Ar is a group containing an aromatic ring, m is an integer from 0 to 5, and n is an integer from 0 to 5.

Furthermore, the case where m is 0 and the case where n is 0 each mean the case where the carbon atom bonded to Ar is directly bonded to the carbon atom of the carbonyl group in the hydrazide group.

As a method for producing the dihydrazide compound of the present invention, for example, the following method can be cited.

That is, first, a dicarboxylic acid having a divalent aliphatic hydrocarbon group is heated in methanol under an acidic catalyst, and then neutralized to obtain a methyl ester derivative. Hydrazine is added to the obtained reactant in methanol to react, thereby obtaining the dihydrazide compound of the present invention.

Examples of the above-mentioned dicarboxylic acids include phenylmalonic acid, tolylmalonic acid, phenylsuccinic acid, tolylsuccinic acid, benzylmalonic acid, benzylsuccinic acid, 2-phenylglutaric acid, 3-phenylglutaric acid, 2-benzylglutaric acid, 3-benzylglutaric acid, 2-phenyladipic acid, 3-phenyladipic acid, 2-benzyladipic acid, 3-benzyladipic acid, etc.

The dihydrazide compound of the present invention is suitable for use as a thermal curing agent mixed into a curable resin composition.

The curable resin composition is also one of the present invention, and the curable resin composition contains a curable resin and a thermosetting agent, and the thermosetting agent contains the dihydrazide compound of the present invention.

The preferred lower limit of the content of the dihydrazide compound of the present invention relative to 100 parts by weight of the curable resin is 3 parts by weight, and the preferred upper limit is 20 parts by weight. When the content of the dihydrazide compound of the present invention is 3 parts by weight or more, the curability or adhesion of the obtained curable resin composition will become better. When the content of the dihydrazide compound of the present invention is 20 parts by weight or less, the storage stability of the obtained curable resin composition will become better, and the low liquid crystal contamination will become better when used as a sealant for liquid crystal display elements. The preferred lower limit of the content of the dihydrazide compound of the present invention is 5 parts by weight, and the preferred upper limit is 15 parts by weight.

In the scope that does not hinder the purpose of the present invention, the curable resin composition of the present invention may contain other thermosetting agents in addition to the dihydrazide compound of the present invention. Examples of the above-mentioned thermosetting agents include organic acid hydrazides, imidazole derivatives, amine compounds, polyphenol compounds, acid anhydrides, etc. other than the dihydrazide compound of the present invention.

The hardening resin composition of the present invention contains a hardening resin.

The above-mentioned curable resin preferably contains an epoxy compound.

Examples of the epoxy compound include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, 2,2'-diallylbisphenol A type epoxy resin, hydrogenated bisphenol type epoxy resin, propylene oxide addition bisphenol A type epoxy resin, resorcinol type epoxy resin, biphenyl type epoxy resin, sulfide type epoxy resin, diphenyl ether type epoxy resin, Epoxy resin, dicyclopentadiene epoxy resin, naphthalene epoxy resin, phenol novolac epoxy resin, o-cresol novolac epoxy resin, dicyclopentadiene novolac epoxy resin, biphenyl novolac epoxy resin, naphthol novolac epoxy resin, glycidylamine epoxy resin, alkyl polyol epoxy resin, rubber modified epoxy resin, glycidyl ester compounds, etc.

Examples of commercially available bisphenol A type epoxy resins include jER828EL, jER1004 (both manufactured by Mitsubishi Chemical Corporation), and EPICLON850 (manufactured by DIC Corporation).

Examples of commercially available bisphenol F-type epoxy resins include jER806, jER4004 (both manufactured by Mitsubishi Chemical Corporation), and EPICLON EXA-830CRP (manufactured by DIC Corporation).

Examples of commercially available bisphenol E-type epoxy resins include Epomic R710 (manufactured by Mitsui Chemicals Co., Ltd.).

Examples of commercially available bisphenol S-type epoxy resins include EPICLON EXA-1514 (manufactured by DIC Corporation).

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

Examples of commercially available hydrogenated bisphenol epoxy resins include EPICLON EXA-7015 (manufactured by DIC Corporation).

Examples of commercially available propylene oxide-added bisphenol A type epoxy resins include EP-4000S (manufactured by ADEKA Corporation).

Examples of commercially available resorcinol-type epoxy resins include EX-201 (manufactured by Nagase Chemicals Co., Ltd.).

Examples of commercially available biphenyl-type epoxy resins include jER YX-4000H (manufactured by Mitsubishi Chemical Corporation).

Examples of commercially available sulfide-type epoxy resins include YSLV-50TE (manufactured by Nippon Steel Chemical Materials Co., Ltd.).

Examples of commercially available diphenyl ether epoxy resins include YSLV-80DE (manufactured by Nippon Steel Chemical Materials Co., Ltd.).

Examples of commercially available dicyclopentadiene epoxy resins include EP-4088S (manufactured by ADEKA Corporation).

Examples of commercially available naphthalene-based epoxy resins include EPICLON HP-4032 and EPICLON EXA-4700 (both manufactured by DIC Corporation).

Examples of commercially available phenol novolac type epoxy resins include EPICLON N-770 (manufactured by DIC Corporation).

Examples of commercially available o-cresol novolac epoxy resins include EPICLON N-670-EXP-S (manufactured by DIC Corporation).

Examples of commercially available dicyclopentadiene novolac type epoxy resins include EPICLON HP-7200 (manufactured by DIC Corporation).

Examples of commercially available biphenyl novolac epoxy resins include NC-3000P (manufactured by Nippon Kayaku Co., Ltd.).

Examples of commercially available naphthol novolac epoxy resins include ESN-165S (manufactured by Nippon Steel Chemical Materials Co., Ltd.).

Examples of the commercially available epoxy resins of the above-mentioned glycidylamine type include: jER630 (manufactured by Mitsubishi Chemical Corporation), EPICLON430 (manufactured by DIC Corporation), TETRAD-X (manufactured by Mitsubishi Gas Chemical Corporation), etc.

Examples of commercially available alkyl polyol epoxy resins include: ZX-1542 (manufactured by Nippon Steel Chemical Materials Co., Ltd.), EPICLON726 (manufactured by DIC Corporation), Epolight 80MFA (manufactured by Kyoeisha Chemical Co., Ltd.), and DENACOL EX-611 (manufactured by Nagase Chemicals Co., Ltd.).

Examples of the above-mentioned rubber-modified epoxy resins that are commercially available include: YR-450, YR-207 (both manufactured by Nippon Steel Chemical Materials Co., Ltd.), Epolead PB (manufactured by Daicel Co., Ltd.), etc.

Examples of commercially available glycidyl ester compounds include DENACOL EX-147 (manufactured by Nagase Chemicals Co., Ltd.).

Other commercially available epoxy compounds include, for example, YDC-1312, YSLV-80XY, YSLV-90CR (all manufactured by Nippon Steel Chemical Materials Co., Ltd.), XAC4151 (manufactured by Asahi Kasei Corporation), jER1031, jER1032 (all manufactured by Mitsubishi Chemical Corporation), EXA-7120 (manufactured by DIC Corporation), TEPIC (manufactured by Nissan Chemical Co., Ltd.), etc.

As the above-mentioned epoxy compound, it is also appropriate to use partially (meth)acrylic acid-modified epoxy resin.

Furthermore, the above-mentioned partially (meth)acrylic acid-modified epoxy resin in this specification means a compound that can be obtained by reacting a part of the epoxy groups of an epoxy compound having two or more epoxy groups with (meth)acrylic acid, and has one or more epoxy groups and (meth)acrylic acid groups in one molecule.

Furthermore, in this specification, the above-mentioned "(meth)acrylic acid" means acrylic acid or methacrylic acid, and the above-mentioned "(meth)acryl" means acryl or methacryl.

Examples of the commercially available (meth)acrylic modified epoxy resins mentioned above include UVACURE1561 and KRM8287 (both manufactured by DAICEL-ALLNEX).

Furthermore, the above-mentioned curable resin may also contain a (meth) acrylic compound.

Examples of the above-mentioned (meth) acrylic acid compound include (meth) acrylic acid ester compounds, epoxy (meth) acrylic acid esters, urethane (meth) acrylates, etc. Among them, epoxy (meth) acrylic acid esters are preferred. In addition, the above-mentioned (meth) acrylic acid compound is preferably one having two or more (meth) acrylic acid groups in one molecule from the viewpoint of reactivity.

Furthermore, in this specification, the above-mentioned "(meth)acrylic compound" means a compound having a (meth)acrylic group. In addition, the above-mentioned "(meth)acrylate" means acrylate or methacrylate, and the above-mentioned "epoxy (meth)acrylate" means a compound obtained by reacting all epoxy groups in an epoxy compound with (meth)acrylic acid.

Examples of the monofunctional (meth)acrylate compounds include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Lauryl (meth)acrylate, isomyristyl (meth)acrylate, stearyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, cyclohexyl (meth)acrylate, isoborneol (meth)acrylate, dicyclopentenyl (meth)acrylate, benzyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, Ester, 2-butoxyethyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, methoxyethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, tetrahydrofuranmethyl (meth)acrylate, ethyl carbitol (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3- Tetrafluoropropyl, 1H,1H,5H-octafluoropentyl (meth)acrylate, imide (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, 2-(meth)acryloyloxyethyl succinate, 2-(meth)acryloyloxyethyl hexahydrophthalate, 2-(meth)acryloyloxyethyl 2-hydroxypropyl phthalate, 2-(meth)acryloyloxyethyl phosphate, glycidyl (meth)acrylate, etc.

In addition, examples of the bifunctional (meth)acrylate compounds include 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 2-n-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, Polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethylene oxide added bisphenol A di(meth)acrylate, propylene oxide added bisphenol A di(meth)acrylate, ethylene oxide added bisphenol F di(meth)acrylate, dihydroxymethyl dicyclopentadiene di(meth)acrylate, ethylene oxide modified isocyanuric acid di(meth)acrylate, (meth)acrylate 2-hydroxy-3-(meth)acryloyloxypropyl, carbonate diol di(meth)acrylate, polyether diol di(meth)acrylate, polyester diol di(meth)acrylate, polycaprolactone diol di(meth)acrylate, polybutadiene diol di(meth)acrylate, etc.

In addition, as the trifunctional or higher functional (meth)acrylate compounds mentioned above, for example, trihydroxymethylpropane tri(meth)acrylate, ethylene oxide added trihydroxymethylpropane tri(meth)acrylate, propylene oxide added trihydroxymethylpropane tri(meth)acrylate, caprolactone modified trihydroxymethylpropane tri(meth)acrylate, ethylene oxide added isocyanuric acid tri(meth)acrylate, glycerol tri(meth)acrylate, propylene oxide added glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tri(meth)acryloyloxyethyl phosphate, di-trihydroxymethylpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, etc. can be cited.

Examples of the above-mentioned epoxy (meth) acrylate include: those obtained by reacting an epoxy compound with (meth) acrylic acid in the presence of an alkaline catalyst according to a conventional method, etc.

As for the epoxy compound used as the raw material for synthesizing the above-mentioned epoxy (meth) acrylate, the same epoxy compound as the curable resin contained in the curable resin composition of the present invention described above can be used.

Examples of commercially available epoxy (meth)acrylates include epoxy (meth)acrylate manufactured by DAICEL-ALLNEX, epoxy (meth)acrylate manufactured by Shin-Nakamura Chemical Industry, epoxy (meth)acrylate manufactured by Kyoeisha Chemical, and epoxy (meth)acrylate manufactured by Nagase Chemicals.

Examples of epoxy (meth)acrylates manufactured by the above-mentioned DAICEL-ALLNEX company include EBECRYL860, EBECRYL3200, EBECRYL3201, EBECRYL3412, EBECRYL3600, EBECRYL3700, EBECRYL3701, EBECRYL3702, EBECRYL3703, EBECRYL3708, EBECRYL3800, EBECRYL6040, and EBECRYL RDX63182.

Examples of epoxy (meth)acrylates manufactured by the above-mentioned Shin-Nakamura Chemical Industry Co., Ltd. include EA-1010, EA-1020, EA-5323, EA-5520, EA-CHD, EMA-1020, etc.

Examples of the epoxy (meth) acrylates manufactured by the above-mentioned Kyoeisha Chemical Co., Ltd. include: EPOXYESTER M-600A, EPOXYESTER 40EM, EPOXYESTER 70PA, EPOXYESTER 200PA, EPOXYESTER 80MFA, EPOXYESTER 3002M, EPOXYESTER 3002A, EPOXYESTER 1600A, EPOXYESTER 3000M, EPOXYESTER 3000A, EPOXYESTER 200EA, EPOXYESTER 400EA, etc.

Examples of the epoxy (meth) acrylates manufactured by Nagase Chemicals include Denacol Acrylate DA-141, Denacol Acrylate DA-314, Denacol Acrylate DA-911, etc.

The above-mentioned amine (meth)acrylate can be obtained, for example, by reacting a (meth)acrylic acid derivative having a hydroxyl group with an isocyanate compound in the presence of a catalytic amount of a tin-based compound.

Examples of isocyanate compounds that are raw materials for the above-mentioned amine (meth)acrylate include 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, tolidine diisocyanate, stilbene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, thiophosphoric acid tris(isocyanatophenyl) ester, tetramethylstilbene diisocyanate, 1,6,11-undecane triisocyanate, etc.

Furthermore, the isocyanate compound used as the raw material of the above-mentioned amine (meth)acrylate may be an expanded isocyanate compound obtained by reacting a polyol with an excess of an isocyanate compound.

Examples of the above-mentioned polyols include ethylene glycol, propylene glycol, glycerin, sorbitol, trihydroxymethylpropane, carbonate diol, polyether diol, polyester diol, polycaprolactone diol, etc.

Examples of the (meth)acrylic acid derivatives having a hydroxyl group include: hydroxyalkyl mono(meth)acrylate, mono(meth)acrylate of a diol, mono(meth)acrylate or di(meth)acrylate of a triol, epoxy(meth)acrylate, etc.

Examples of the above-mentioned mono(meth)acrylate hydroxyalkyl ester include: 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 2-hydroxybutyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, etc.

Examples of the above-mentioned diols include ethylene glycol, propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, polyethylene glycol, etc.

Examples of the above-mentioned triols include trihydroxymethylethane, trihydroxymethylpropane, glycerol, etc.

Examples of the above-mentioned epoxy (meth) acrylate include bisphenol A type epoxy acrylate, etc.

Examples of the commercially available amine (meth) acrylates include: amine (meth) acrylates manufactured by Toa Synthetics, amine (meth) acrylates manufactured by DAICEL-ALLNEX, amine (meth) acrylates manufactured by Negami Industries, amine (meth) acrylates manufactured by Shin-Nakamura Chemical Industries, amine (meth) acrylates manufactured by Kyoeisha Chemicals, etc.

Examples of the amine (meth)acrylates manufactured by the aforementioned Toa Gosei Co., Ltd. include: M-1100, M-1200, M-1210, M-1600, etc.

Examples of the amine (meth)acrylates manufactured by the above-mentioned DAICEL-ALLNEX company include EBECRYL210, EBECRYL220, EBECRYL230, EBECRYL270, EBECRYL1290, EBECRYL2220, EBECRYL4827, EBECRYL4842, EBECRYL4858, EBECRYL5129, EBECRYL6700, EBECRYL8402, EBECRYL8803, EBECRYL8804, EBECRYL8807, EBECRYL9260, etc.

Examples of amine (meth)acrylates manufactured by the aforementioned Negami Industries include Artresin UN-330, Artresin SH-500B, Artresin UN-1200TPK, Artresin UN-1255, Artresin UN-3320HB, Artresin UN-7100, Artresin UN-9000A, Artresin UN-9000H, etc.

Examples of the amine (meth)acrylates manufactured by Shin-Nakamura Chemical Industry Co., Ltd. include: 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, etc.

Examples of amine (meth)acrylates manufactured by the aforementioned Kyoeisha Chemical Co., Ltd. include: AH-600, AI-600, AT-600, UA-101I, UA-101T, UA-306H, UA-306I, UA-306T, etc.

When the curable resin contains the (meth)acrylic compound in addition to the epoxy compound, or when the curable resin contains the partially (meth)acrylic modified epoxy compound, it is preferred that the ratio of the (meth)acrylic group in the total of the epoxy group and the (meth)acrylic group in the curable resin is 30 mol% or more and 95 mol% or less. When the ratio of the (meth)acrylic group is within this range, the adhesiveness of the obtained curable resin composition will be better, and when used as a sealant for liquid crystal display elements, the low liquid crystal contamination property will be better.

From the viewpoint of further suppressing liquid crystal contamination, the curable resin preferably has a hydrogen bonding unit such as an -OH group, a -NH- group, or a -NH ₂ group.

The curable resin composition of the present invention preferably further contains a photo-radical polymerization initiator.

化合物等。 Examples of the photoradical polymerization initiator include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, 9-oxysulfide

Compounds, etc.

啉基苯基)-1-丁酮、2-(二甲胺基)-2-((4-甲基苯基)甲基)-1-(4-(4-

啉基)苯基)-1-丁酮、2,2-二甲氧基-1,2-二苯乙烷-1-酮、雙(2,4,6-三甲基苯甲醯基)苯基膦氧化物、2-甲基-1-(4-甲硫基苯基)-2-

啉基丙烷-1-酮、1-(4-(2-羥基乙氧基)-苯基)-2-羥基-2-甲基-1-丙烷-1-酮、1-(4-(苯硫基)苯基)-1,2-辛二酮2-(O-苯甲醯基肟)(1-(4-(phenylthio)phenyl)-1,2-octanedione 2-(O-benzoyloxime))、2,4,6-三甲基苯甲醯基二苯基膦氧化物等。 Specific examples of the photoradical polymerization initiator include 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1-(4-

1-Butanone, 2-(dimethylamino)-2-((4-methylphenyl)methyl)-1-(4-(4-

1-Butanone, 2,2-dimethoxy-1,2-diphenylethane-1-one, bis(2,4,6-trimethylbenzyl)phenylphosphine oxide, 2-methyl-1-(4-methylthiophenyl)-2-

1-(4-(2-hydroxyethoxy)phenyl)-2-hydroxy-2-methyl-1-propane-1-one, 1-(4-(phenylthio)phenyl)-1,2-octanedione 2-(O-benzoyloxime)), 2,4,6-trimethylbenzyldiphenylphosphine oxide, etc.

The above-mentioned photo-radical polymerization initiators can be used alone or in combination of two or more.

The content of the above-mentioned photo-radical polymerization initiator is preferably 0.5 parts by weight and the upper limit is preferably 10 parts by weight relative to 100 parts by weight of the above-mentioned curable resin. When the content of the above-mentioned photo-radical polymerization initiator is within this range, the storage stability or photocurability of the obtained curable resin composition will become better, and the low liquid crystal contamination property when used as a sealant for liquid crystal display elements will become better. The lower limit of the content of the above-mentioned photo-radical polymerization initiator is preferably 1 part by weight, and the upper limit is preferably 7 parts by weight.

The curable resin composition of the present invention may also contain a thermal free radical polymerization initiator.

As the above-mentioned thermal free radical polymerization initiator, for example, there can be cited those composed of azo compounds or organic peroxides. Among them, from the perspective of suppressing liquid crystal contamination when the obtained curable resin composition is used as a sealant for liquid crystal display elements, an initiator composed of an azo compound (hereinafter also referred to as "azo initiator") is preferred, and an initiator composed of a polymer azo compound (hereinafter also referred to as "polymer azo initiator") is more preferred.

The above-mentioned thermal free radical polymerization initiators can be used alone or in combination of two or more.

Furthermore, the above-mentioned "polymer azo compound" in this specification means a compound having an azo group, generating free radicals capable of curing (meth)acrylic groups by heat, and having a number average molecular weight of 300 or more.

The preferred lower limit of the number average molecular weight of the above-mentioned high molecular azo compound is 1000, and the preferred upper limit is 300,000. By having the number average molecular weight of the above-mentioned high molecular azo compound within this range, it is possible to prevent the obtained curable resin composition from having adverse effects on liquid crystal when used as a sealant for liquid crystal display elements, and to easily mix it into the curable resin. The preferred lower limit of the number average molecular weight of the above-mentioned high molecular azo compound is 5000, the preferred upper limit is 100,000, the further preferred lower limit is 10,000, and the further preferred upper limit is 90,000.

Furthermore, in this specification, the above number average molecular weight is a value obtained by polystyrene conversion by measuring a tetrahydrofuran solution with a sample concentration of 0.5% by weight at a flow rate of 1 mL/min by gel permeation chromatography (GPC). GPC can use, for example, HPLC-9210 2NEXT (manufactured by Japan Analytical Science Co., Ltd.), and as a column used in GPC, for example, JAIGEL2H (manufactured by Japan Analytical Science Co., Ltd.) can be cited.

As the above-mentioned high molecular weight azo compound, for example, there can be cited a structure having a plurality of units such as polyepoxide or polydimethylsiloxane bonded via an azo group.

As the polymer azo compound having a structure in which a plurality of units such as polyoxyalkylene are bonded via an azo group, it is preferred to have a polyethylene oxide structure.

As the above-mentioned high molecular weight azo compound, specifically, for example, there can be mentioned a condensate of 4,4'-azobis(4-cyanovaleric acid) and polyalkylene glycol, or a condensate of 4,4'-azobis(4-cyanovaleric acid) and polydimethylsiloxane having a terminal amino group.

Examples of the commercially available polymer azo initiators include: VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS-1001 (all manufactured by Fuji Film and Koshun Chemical Co., Ltd.).

In addition, as non-polymer azo initiators, examples include V-65 and V-501 (both manufactured by Fuji Film and Koshun Chemical Co., Ltd.).

Examples of the above-mentioned organic peroxides include ketone peroxide, peroxy ketal, hydroperoxide, dialkyl peroxide, peroxyester, diacyl peroxide, peroxydicarbonate, etc.

The content of the thermal free radical polymerization initiator is preferably 0.1 parts by weight and 10 parts by weight relative to 100 parts by weight of the curable resin. When the content of the thermal free radical polymerization initiator is within this range, the storage stability or thermal curability of the obtained curable resin composition will become better, and the low liquid crystal contamination property when used as a sealant for liquid crystal display elements will become better. The better lower limit of the content of the thermal free radical polymerization initiator is 0.3 parts by weight and the better upper limit is 5 parts by weight.

The curable resin composition of the present invention may also contain fillers for the purpose of increasing viscosity, improving adhesion under stress dispersion effect, improving linear expansion rate, and improving moisture resistance of the cured product.

As the above-mentioned filler, an inorganic filler or an organic filler can be used.

Examples of the above-mentioned inorganic fillers include: silicon dioxide, talc, glass beads, sponge, gypsum, diatomaceous earth, bentonite, bentonite, montmorillonite, sericite, activated clay, aluminum oxide, 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, etc.

Examples of the above-mentioned organic fillers include polyester microparticles, polyurethane microparticles, vinyl polymer microparticles, acrylic polymer microparticles, etc.

The above fillers can be used alone or in combination of two or more.

The preferred lower limit of the content of the above filler in 100 parts by weight of the curable resin composition of the present invention is 10 parts by weight, and the preferred upper limit is 70 parts by weight. When the content of the above filler is within this range, the effect of improving adhesion can be improved without deteriorating the coating properties. The preferred lower limit of the content of the above filler is 20 parts by weight, and the preferred upper limit is 60 parts by weight.

The curable resin composition of the present invention may also contain a silane coupling agent. The above-mentioned silane coupling agent mainly serves as a bonding aid to enable the curable resin composition to be well bonded to the substrate, etc.

As the above-mentioned silane coupling agent, for example, 3-aminopropyltrimethoxysilane, 3-butylpropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-isocyanatepropyltrimethoxysilane, etc. are suitable. These are excellent in improving the adhesion with the substrate, etc., and when the obtained curable resin composition is used as a sealant for liquid crystal display elements, it can inhibit the curable resin from flowing out into the liquid crystal.

The above-mentioned silane coupling agents can be used alone or in combination of two or more.

The preferred lower limit of the content of the above-mentioned silane coupling agent in 100 parts by weight of the curable resin composition of the present invention is 0.1 parts by weight, and the preferred upper limit is 10 parts by weight. When the content of the above-mentioned silane coupling agent is within this range, the effect of improving adhesion becomes more excellent, and when the obtained curable resin composition is used as a sealant for liquid crystal display elements, the low liquid crystal contamination becomes more excellent. The preferred lower limit of the content of the above-mentioned silane coupling agent is 0.3 parts by weight, and the preferred upper limit is 5 parts by weight.

The curable resin composition of the present invention may also contain a sunscreen. By containing the above-mentioned sunscreen, the curable resin composition of the present invention can be suitably used as a sunscreen sealant.

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

The titanium black is a substance that has a higher transmittance to light near the ultraviolet region, especially to light with a wavelength of 370 nm to 450 nm, than the average transmittance to light with a wavelength of 300 nm to 800 nm. That is, the titanium black is a light-shielding agent that provides light-shielding properties to the curable resin composition of the present invention by fully blocking light with a wavelength in the visible light region, and has the property of transmitting light with a wavelength near the ultraviolet region. Therefore, by using a substance that can initiate a reaction with light of a wavelength whose transmittance of the titanium black is increased as the photo-radical polymerization initiator, the photocurability of the curable resin composition of the present invention can be further increased. On the other hand, the sunscreen contained in the curable resin composition of the present invention is preferably a substance with high insulation properties, and titanium black is also suitable as a sunscreen with high insulation properties.

The optical density (OD value) of the titanium black per 1μm is preferably 3 or more, and more preferably 4 or more. The higher the light shielding property of the titanium black, the better. There is no particular upper limit for the OD value of the titanium black, which is usually below 5.

The above-mentioned titanium black can fully exert its effect even if it is not surface treated, but titanium black that has been surface treated by an organic component such as a coupling agent, or coated with an inorganic component such as silicon oxide, titanium oxide, germanium oxide, aluminum oxide, zirconium oxide, and magnesium oxide can also be used. Among them, those treated with organic components are better in terms of improving insulation.

Furthermore, the display element manufactured using the curable resin composition of the present invention mixed with the above-mentioned titanium black as a light-shielding agent has sufficient light-shielding properties, so there is no light leakage and it has a higher contrast, which can realize a display element with excellent image display quality.

Examples of the titanium blacks available on the market include the titanium blacks manufactured by Mitsubishi Materials Corporation and the titanium blacks manufactured by Ako Chemicals Corporation.

Examples of titanium black manufactured by Mitsubishi Materials Corporation include: 12S, 13M, 13M-C, 13R-N, 14M-C, etc.

Examples of titanium black produced by the aforementioned Ako Chemical Co., Ltd. include Tilack D.

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 titanium black is 0.5Ω. cm, the preferred upper limit is 3Ω. cm, the better lower limit is 1Ω. cm, and the better upper limit is 2.5Ω. cm.

The preferred lower limit of the primary particle size of the above-mentioned sunscreen is 1nm, and the preferred upper limit is 5000nm. By having the primary particle size of the above-mentioned sunscreen within this range, the obtained curable resin composition can have a better light-shielding property without deteriorating the coating properties. The preferred lower limit of the primary particle size of the above-mentioned sunscreen is 5nm, and the preferred upper limit is 200nm. The further preferred lower limit is 10nm, and the further preferred upper limit is 100nm.

Furthermore, the primary particle size of the above-mentioned sunscreen can be measured by dispersing the above-mentioned sunscreen in a solvent (water, organic solvent, etc.) using NICOMP 380ZLS (manufactured by PARTICLE SIZING SYSTEMS).

The preferred lower limit of the content of the above-mentioned sunscreen in 100 parts by weight of the curable resin composition of the present invention is 5 parts by weight, and the preferred upper limit is 80 parts by weight. When the content of the above-mentioned sunscreen is within this range, it is possible to exert a more excellent sunscreen without significantly reducing the adhesion, strength after curing and drawing properties of the obtained curable resin composition. The preferred lower limit of the content of the above-mentioned sunscreen is 10 parts by weight, the preferred upper limit is 70 parts by weight, the further preferred lower limit is 30 parts by weight, and the further preferred upper limit is 60 parts by weight.

The curable resin composition of the present invention may further contain additives such as stress relievers, reactive diluents, thixotropic agents, spacers, curing accelerators, defoamers, leveling agents, polymerization inhibitors, etc. as needed.

As a method for producing the curable resin composition of the present invention, for example, there can be cited a method of mixing the curable resin, the thermosetting agent, and the photo-radical polymerization initiator added as needed using a mixer.

Examples of the above-mentioned mixer include: a homogeneous disperser, a homogenizing mixer, a universal mixer, a planetary mixer, a kneader, a three-roll grinder, etc.

The curable resin composition of the present invention is suitable for use as a sealant for display elements, and is particularly suitable for use as a sealant for liquid crystal display elements. A sealant for liquid crystal display elements made using the curable resin composition of the present invention is also one of the present inventions.

By mixing conductive microparticles into the sealant for liquid crystal display elements of the present invention, it is possible to manufacture a vertical conductive material. This vertical conductive material containing the sealant for liquid crystal display elements of the present invention and conductive microparticles is also one of the present invention.

As the above-mentioned conductive microparticles, for example, metal spheres, resin microparticles with a conductive metal layer formed on the surface, etc. can be used. Among them, resin microparticles with a conductive metal layer formed on the surface are suitable because they can achieve conductive connection without damaging transparent substrates, etc. due to the excellent elasticity of the resin microparticles.

A liquid crystal display element using the sealant for liquid crystal display elements of the present invention or the upper and lower conductive material of the present invention is also one of the present invention.

The sealant for the liquid crystal display element of the present invention has a lower compatibility with liquid crystal molecules having polar groups. Therefore, when the liquid crystal display element of the present invention uses liquid crystal containing liquid crystal molecules having polar groups, the effect of suppressing display defects becomes more significant compared to the previous sealant. That is, the liquid crystal display element of the present invention preferably uses liquid crystal containing liquid crystal molecules having polar groups.

As the polar groups of the above-mentioned liquid crystal molecules, for example, there can be cited: fluorine group, chlorine group, cyano group, etc.

As the liquid crystal display element of the present invention, it is preferably a liquid crystal display element with a narrow edge design. Specifically, the width of the frame part around the liquid crystal display part is preferably less than 2 mm.

Furthermore, when manufacturing the liquid crystal display element of the present invention, the coating width of the curable resin composition of the present invention is preferably less than 1 mm.

The sealant for liquid crystal display elements of the present invention can be suitably used in the manufacture of liquid crystal display elements using a liquid crystal dropping method.

As a method for manufacturing the liquid crystal display element of the present invention by the liquid crystal dropping method, for example, the following method can be cited.

First, a step of forming a frame-shaped sealing pattern on a substrate is performed, and the pattern is formed by screen printing, dispensing, etc. of the sealant for the liquid crystal display element of the present invention. Secondly, the following step is performed, when the sealant for the liquid crystal display element of the present invention is not hardened, tiny droplets of liquid crystal are added and applied to the entire surface of the frame of the sealing pattern, and immediately overlapped with another substrate. Thereafter, a liquid crystal display element can be obtained by performing a step of heating the sealant to harden it. In addition, before the step of heating the sealant to harden it, a step of irradiating the sealing pattern part with light such as ultraviolet rays to temporarily harden the sealant can be performed.

According to the present invention, a novel dihydrazide compound can be provided. In addition, the present invention can provide a curable resin composition containing the dihydrazide compound and having excellent storage stability, curability and adhesion, and a sealant for liquid crystal display elements, a top-bottom conductive material and a liquid crystal display element having excellent low liquid crystal contamination properties formed by using the curable resin composition.

The present invention is further described in detail below by presenting embodiments, but the present invention is not limited to these embodiments.

(Synthesis Example 1 (Synthesis of phenylsuccinic acid dihydrazide))

Add 50 mL of methanol, 19.4 g of phenylsuccinic acid and 0.49 g of sulfuric acid to an eggplant-shaped flask and react under reflux for 10 hours. After cooling the reaction solution to room temperature, add 1.11 g of triethylamine for neutralization, and then add 20.0 g of hydrazine monohydrate and react at 25°C for 6 hours. Use a Kiriyama funnel to recover the precipitate by filtration, wash it with methanol, and then vacuum dry it to obtain phenylsuccinic acid dihydrazide (the compound represented by the above formula (2)).

Furthermore, the structure of the obtained phenylsuccinic acid dihydrazide was confirmed by ¹ H-NMR, MS and FT-IR.

(Synthesis Example 2 (Synthesis of benzylmalonic acid dihydrazide))

Benzylmalonic acid dihydrazide (a compound in which Ar is benzyl, m is 0, and n is 0 in the above formula (1)) was obtained in the same manner as in Synthesis Example 1 except that 19.4 g of phenylsuccinic acid was replaced with 19.4 g of benzylmalonic acid.

Furthermore, the structure of the obtained benzylmalonic acid dihydrazide was confirmed by ¹ H-NMR, MS and FT-IR.

(Synthesis Example 3 (Synthesis of phenylmalonic acid dihydrazide))

Except that 19.4g of phenylsuccinic acid was replaced with 18.0g of phenylmalonic acid, phenylmalonic acid dihydrazide (a compound in which Ar is phenyl, m is 0, and n is 0 in the above formula (1)) was obtained in the same manner as in Synthesis Example 1.

Furthermore, the structure of the obtained phenylmalonic acid dihydrazide was confirmed by ¹ H-NMR, MS and FT-IR.

(Examples 1 to 5, Comparative Examples 1 to 3)

According to the blending ratio listed in Table 1, each material was mixed using a planetary mixer (manufactured by Thinky, "Defoaming Mixer Taro"), and then mixed using a three-roll grinder to prepare each hardening resin composition of Examples 1 to 5 and Comparative Examples 1 to 3.

<Evaluation>

The following evaluations were performed on each of the curable resin compositions obtained in the Examples and Comparative Examples. The results are shown in Table 1.

(Maintain stability)

For each hardening resin composition obtained in the embodiment and the comparative example, the initial viscosity immediately after production and the viscosity after storage at 25°C for 1 week after production were measured. (Viscosity after storage)/(initial viscosity) was set as the viscosity increase rate, and the viscosity increase rate was recorded as "○" when it was less than 1.05, "△" when it was more than 1.05 but less than 1.10, and "×" when it was more than 1.10, and the storage stability was evaluated.

Furthermore, the viscosity of the curable resin composition was measured using an E-type viscometer (manufactured by Brookfield, "DV-III") at 25°C and a rotation speed of 1.0 rpm.

(hardening)

For each of the curable resin compositions obtained in the Examples and Comparative Examples, after irradiating with ultraviolet light of 100 mW/ ^cm2 for 30 seconds using a metal halogen lamp, the reaction rate of the epoxy group (the reduction rate of the peak derived from the epoxy group) when cured by heating at 120°C for 1 hour was measured using an infrared spectrometer. The case where the reaction rate was 90% or more was marked as "○", the case where it was 80% or more but less than 90% was marked as "△", and the case where it was less than 80% was marked as "×" to evaluate the curability.

Furthermore, the infrared spectrometer used was UMA600 (manufactured by Agilent Technologies).

(Continuity)

Each of the curable resin compositions obtained in the examples and comparative examples was filled into a dispensing syringe ("PSY-10E", manufactured by Musashi High-Tech Co., Ltd.) and defoamed. The defoamed curable resin composition was dispensed on the inner sides of a glass substrate (150 mm × 150 mm) 30 mm from the edge using a dispensing machine ("SHOTMASTER300", manufactured by Musashi High-Tech Co., Ltd.), and another glass substrate (110 mm × 110 mm) was overlapped and bonded under vacuum. The curable resin composition was temporarily cured by irradiating ultraviolet rays of 100 mW/cm ² with a metal halogen lamp for 30 seconds, and then heated at 120°C for 1 hour to thermally cure the curable resin composition, thereby obtaining a continuous test piece. When a metal rod with a radius of 5 mm is pressed into the end of the substrate of the obtained bonding test piece at a speed of 5 mm/min, the strength (kgf) when the panel peels off is measured and the bonding force (kg/cm) is calculated.

The bonding strength was evaluated by marking "○" for bonding strength of 150 kg/cm or more, "△" for bonding strength of 100 kg/cm or more but less than 150 kg/cm, and "×" for bonding strength less than 100 kg/cm.

(Low liquid crystal contamination)

1 part by weight of spacer particles with an average particle size of 5 μm (manufactured by Sekisui Chemical Industry Co., Ltd., "Micropearl SI-H050") was dispersed in 100 parts by weight of each hardening resin composition obtained in the Examples and Comparative Examples, filled into a syringe, and defoamed using a centrifugal defoamer (AWATRON AW-1). Using a dispenser, the hardening resin composition after defoaming was applied in a frame shape on one of the substrates with two alignment films and ITO under the conditions of a nozzle diameter of 0.4 mmΦ, a nozzle distance of 42 μm, a syringe ejection pressure of 100-400 kPa, and a coating speed of 60 mm/sec. At this time, the ejection pressure is adjusted so that the line width of the curable resin composition becomes about 1.5 mm. Then, tiny droplets of liquid crystal (manufactured by Tokyo Chemical Industry Co., Ltd., "4-pentyl-4-biphenylcarbonitrile") are added and applied to the entire surface of the curable resin composition frame of the substrate coated with the curable resin composition, and then bonded to another substrate under vacuum. Immediately after bonding, the curable resin composition is partially irradiated with 100mW/ ^cm2 ultraviolet light for 30 seconds using a metal halogen lamp to temporarily cure the curable resin composition. Next, it is heated at 120°C for 1 hour for formal curing to produce a liquid crystal display element.

The obtained liquid crystal display elements were visually checked for liquid crystal alignment disorder (uneven display) near the sealant after the liquid crystal display elements were made. Alignment disorder was judged based on the color unevenness of the display part. The situation where there was no uneven display in the liquid crystal display element was recorded as "○", the situation where there was uneven display in the peripheral part (within 500μm from the curable resin composition) was recorded as "△", and the situation where the uneven display not only existed in the peripheral part but also spread more than 500μm and even reached the central part was recorded as "×", and the low liquid crystal contamination was evaluated.

[Table 1]

[Industrial availability]

According to the present invention, a novel dihydrazide compound can be provided. In addition, the present invention can provide a curable resin composition containing the dihydrazide compound and having excellent storage stability, curability and adhesion, and a sealant for liquid crystal display elements, a top-bottom conductive material and a liquid crystal display element having excellent low liquid crystal contamination properties formed by using the curable resin composition.

Claims (5)

A sealant for a liquid crystal display element is formed by using a curable resin composition containing a curable resin and a thermosetting agent, wherein the thermosetting agent contains a dihydrazide compound represented by the following formula (1): In formula (1), Ar is a phenyl group or a benzyl group, m is an integer from 0 to 5, and n is an integer from 0 to 5. The sealant for a liquid crystal display element according to claim 1, wherein the dihydrazide compound is represented by the following formula (2): . The sealant for liquid crystal display element according to claim 1 or 2 further contains a photo-radical polymerization initiator. A vertical conductive material comprises the sealant for liquid crystal display elements of claim 1, 2 or 3 and conductive fine particles. A liquid crystal display element is formed by using the sealant for liquid crystal display element of claim 1, 2 or 3 or the top-bottom conductive material of claim 4.