JP2017204004A - Sealant for liquid crystal display, vertical conduction member, and liquid crystal display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealant for a liquid crystal display excellent in adhesiveness and moisture permeation prevention.SOLUTION: There is provided a sealant for a liquid crystal display containing a curable resin, a polymerization initiator and/or a thermal curing agent, the sealant for a liquid crystal display having a storage elastic modulus at 25°C of 0.8 to 3.0 PGa when cured into a cured product and a glass transition temperature of 46°C or more and less than 60°C when cured into a cured product.SELECTED DRAWING: None

Description

The present invention relates to a sealant for liquid crystal display elements that is excellent in adhesiveness and moisture permeation prevention. Moreover, this invention relates to the vertical conduction material and liquid crystal display element which use this sealing compound for liquid crystal display elements.

In recent years, as a method for manufacturing a liquid crystal display element, a curable resin, a photopolymerization initiator, and a heat as disclosed in Patent Document 1 and Patent Document 2 from the viewpoint of shortening tact time and optimizing the amount of liquid crystal used. A liquid crystal dropping method called a dropping method using a photothermal combined curing type sealing agent containing a curing agent is used.

In the dropping method, first, a rectangular seal pattern is formed on one of two transparent substrates with electrodes by dispensing. Next, a liquid crystal micro-droplet is dropped on the entire surface of the transparent substrate frame in a state where the sealant is uncured, and the other transparent substrate is immediately overlaid, and the seal portion is irradiated with light such as ultraviolet rays for temporary curing. . Thereafter, heating is performed to perform main curing, and a liquid crystal display element is manufactured. A liquid crystal display element can be manufactured with extremely high efficiency by bonding the substrates under a reduced pressure, and this dropping method is currently the mainstream method for manufacturing liquid crystal display elements.

With the spread of tablet terminals and mobile terminals, liquid crystal display elements are increasingly required to have durability against impact tests, drop tests, and the like, and more and more require adhesion to substrates. Further, along with the narrowing of the frame of the panel, moisture resistance reliability is required for driving in a high temperature and high humidity environment, and the sealing agent is further required to have the ability to prevent water from entering from the outside. In order to improve the impact resistance and moisture resistance reliability of the liquid crystal display element, it is necessary to improve the adhesiveness between the sealing agent and the substrate and lower the moisture permeability of the cured product of the sealing agent. However, it has been difficult to produce a sealing agent that is excellent in both adhesion and moisture permeation prevention.

JP 2001-133794 A JP-A-5-295087

The present invention relates to a sealant for liquid crystal display elements that is excellent in adhesiveness and moisture permeation prevention. Another object of the present invention is to provide a vertical conduction material and a liquid crystal display element using the sealing agent for a liquid crystal display element.

The present invention is a sealant for a liquid crystal display element containing a curable resin and a polymerization initiator and / or a thermosetting agent, and the cured product has a storage elastic modulus at 25 ° C. of 0.8 to 3.0 GPa. And it is the sealing compound for liquid crystal display elements whose glass transition temperature of hardened | cured material is 46 degreeC or more and less than 60 degreeC.
The present invention is described in detail below.

The present inventor has found that a sealing agent for a liquid crystal display element excellent in both adhesiveness and moisture permeation-preventing property can be obtained by adjusting the storage elastic modulus at 25 ° C. of the cured product within a specific range. The present invention has been completed.

As for the sealing compound for liquid crystal display elements of this invention, the minimum of the storage elastic modulus in 25 degreeC of hardened | cured material is 0.8 GPa, and an upper limit is 3.0 GPa. When the storage elastic modulus at 25 ° C. of the cured product is within this range, the sealing agent for liquid crystal display elements of the present invention is excellent in both adhesion and moisture permeation prevention. The preferable lower limit of the storage elastic modulus at 25 ° C. of the cured product is 1.0 GPa, the preferable upper limit is 2.8 GPa, the more preferable lower limit is 1.2 GPa, and the more preferable upper limit is 2.6 GPa.
The cured product for measuring the storage elastic modulus at 25 ° C. and the storage elastic modulus at 60 ° C. described later is irradiated with 100 mW / cm ² ultraviolet rays (wavelength 365 nm) for 30 seconds using a metal halide lamp as a sealant. And then cured by heating at 120 ° C. for 1 hour.
The storage elastic modulus is measured using a dynamic viscoelasticity measuring apparatus (for example, “DVA-200” manufactured by IT Measurement Control Co., Ltd.) at each measurement temperature, with a test piece width of 5 mm, a thickness of 0.35 mm, and a grip. It can be measured under the conditions of a width of 25 mm, a temperature rising rate of 10 ° C./min, and a frequency of 10 Hz.

As for the sealing compound for liquid crystal display elements of this invention, the preferable minimum of the storage elastic modulus in 60 degreeC of hardened | cured material is 0.04 GPa. When the storage elastic modulus at 60 ° C. of the cured product is 0.04 GPa or more, the sealing agent for liquid crystal display elements of the present invention is more excellent in moisture permeability prevention. The minimum with more preferable storage elastic modulus in 60 degreeC of the said hardened | cured material is 0.1 GPa.
Moreover, from a viewpoint of adhesiveness, the upper limit with the preferable storage elastic modulus in 60 degreeC of the said hardened | cured material is 2.5 GPa.

The sealing agent for liquid crystal display elements of this invention contains curable resin, a polymerization initiator, and / or a thermosetting agent.
In the sealing agent for liquid crystal display elements of the present invention, as a method of setting the storage elastic modulus at 25 ° C. of the cured product to 0.8 to 3.0 GPa, as the curable resin, one or more polymerizations per molecule. A polymerizable compound having a polymerizable functional group and one or more lactone ring-opening structures and / or one or more acrylonitrile-butadiene structures (hereinafter also referred to as “polymerizable compound (a)”) is used. In addition to the above polymerizable compound (a), the method is suitable, and it has one polymerizable functional group in one molecule, and it does not have a ring opening structure of lactone and an acrylonitrile-butadiene structure. A method using a compound containing a polymerizable compound (hereinafter also referred to as “polymerizable compound (b)”) is more preferable.

As a polymeric functional group which the said polymeric compound (a) has, a (meth) acryloyl group, an epoxy group, etc. are mentioned, for example. Of these, a (meth) acryloyl group is preferable.
In the present specification, the “(meth) acryloyl” means acryloyl or methacryloyl.
The polymerizable compound (a) is preferably a polyfunctional polymerizable compound having two or more polymerizable functional groups in one molecule.

When the polymerizable compound (a) has a lactone ring-opening structure, examples of the lactone include γ-undecalactone, ε-caprolactone, γ-decalactone, σ-dodecalactone, γ-nonalactone, and γ-nonanolactone. , Γ-valerolactone, σ-valerolactone, β-butyrolactone, γ-butyrolactone, β-propiolactone, σ-hexanolactone, 7-butyl-2-oxepanone and the like. Among them, those in which the straight chain portion of the main skeleton has 5 to 7 carbon atoms when ring-opened are preferable, and ε-caprolactone is more preferable. Among these, the polymerizable compound (a) may have a ring-opening structure of one kind of lactone, or may have a ring-opening structure of two or more kinds of lactones.

When the polymerizable compound (a) has a ring opening structure of a lactone, the ring opening structure of the lactone may be only one per molecule or may be a repeating structure. When the lactone ring-opening structure is a repeating structure, the preferred upper limit of the number of repetitions is 5.

The minimum with a preferable molecular weight of the said polymeric compound (a) is 800, and a preferable upper limit is 4000. When the molecular weight of the polymerizable compound (a) is within this range, the obtained sealing agent for liquid crystal display elements is more excellent in flexibility and moisture permeability prevention. The upper limit with more preferable molecular weight of the said polymeric compound (a) is 2000.
In the present specification, the “molecular weight” is a molecular weight obtained from the structural formula for a compound whose molecular structure is specified, but for a compound having a wide distribution of polymerization degree and a compound whose modification site is unspecified, Sometimes expressed using weight average molecular weight. Further, the “weight average molecular weight” is a value determined by polystyrene conversion after measurement by gel permeation chromatography (GPC). As a column used when measuring the weight average molecular weight by polystyrene conversion by GPC, Shodex LF-804 (made by Showa Denko KK) etc. are mentioned, for example.

Among the polymerizable compounds (a), those having a lactone ring-opening structure are preferably those in which a lactone ring-opening structure is introduced into the epoxy (meth) acrylate skeleton described later. As what introduce | transduced the ring-opening structure of lactone in the frame | skeleton of the said epoxy (meth) acrylate, the compound etc. which are represented by following formula (1) are mentioned, for example.

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), and R ³ represents a structure derived from an acid anhydride. R ⁴ represents an epoxy compound-derived structure, X represents a ring-opening structure of lactone, n represents an integer of 1 to 5, and a represents an integer of 1 to 4.

In formula (2-2), b represents an integer of 0 to 8, c represents an integer of 0 to 3, d represents an integer of 0 to 8, e represents an integer of 0 to 8, b, Any one of c and d is 1 or more.

Specific examples of the polymerizable compound (a) include caprolactone-modified bisphenol A type epoxy (meth) acrylate, terminal carboxyl group-containing polybutadiene-acrylonitrile (CTBN) modified epoxy (meth) acrylate, and ethylene glycol modified A type epoxy. (Meth) acrylate etc. are mentioned. The said polymeric compound (a) may be used independently and may be used in combination of 2 or more type.

The minimum with preferable content of the said polymeric compound (a) in 100 weight part of the said whole curable resin is 5 weight part, and a preferable upper limit is 80 weight part. When the content of the polymerizable compound (a) is within this range, the storage modulus of the cured product at 25 ° C. can be easily set within the above-described range. The minimum with more preferable content of the said polymeric compound (a) is 10 weight part, and a more preferable upper limit is 60 weight part.

Examples of the polymerizable functional group possessed by the polymerizable compound (b) include those similar to the polymerizable compound (a), and a (meth) acryloyl group is preferred.

The polymerizable compound (b) preferably has a hydrogen bonding functional group from the viewpoint of suppressing liquid crystal contamination.
Examples of the hydrogen bonding functional group include —OH group, —NH ₂ group, —NHR group (R represents an aromatic or aliphatic hydrocarbon, and derivatives thereof), —COOH group, —CONH. Examples thereof include functional groups such as _two groups and —NHOH groups, and —NHCO— bonds, —NH— bonds, —CONHCO— bonds, and —NH—NH— bonds present in the molecule. Of these, -OH group is preferable.

The minimum with a preferable molecular weight of the said polymeric compound (b) is 100, and a preferable upper limit is 2000. When the molecular weight of the polymerizable compound (b) is 100 or more, it is difficult to elute into the liquid crystal. When the molecular weight of the polymerizable compound (b) is 2000 or less, the obtained sealing agent for liquid crystal display elements is more excellent in applicability. The minimum with more preferable molecular weight of the said polymeric compound (b) is 150, and a more preferable upper limit is 1000.

Specific examples of the polymerizable compound (b) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth). Acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, 2-(((butylamino) carbonyl) oxy ) Ethyl (meth) acrylate, aliphatic epoxy (meth) acrylate (for example, EBECRYL112 (manufactured by Daicel Ornex)), caprolactone (meth) acrylate (for example, SR495 (manufactured by Sartomer)), polypropylene glycol mono (meth) a Relate (for example, SR604 (manufactured by Sartomer)), caprolactone-modified urethane (meth) acrylate (for example, KUA-C2I (manufactured by KSM)), polycarbonate-modified urethane (meth) acrylate (for example, KUA-PC2I (manufactured by KSM) ), Polyether-modified urethane (meth) acrylate (for example, KUA-PEA2I, KUA-PEB2I, KUA-PEC2I (all manufactured by KSM)), β-carboxyethyl (meth) acrylate (for example, β-CEA (Daicel Ornex Corp.)), carboxy (meth) acrylate (eg, EBECRYL770 (Daicel Ornex Corp.)), methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (Meth) acrylate, isobutyl (meth) acrylate, t-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, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, bicyclopentenyl (meth) acrylate, benzyl (meth) acrylate, 2-methoxyethyl (Meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, methoxy Tylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, ethyl carbitol (meth) acrylate, 2,2, 2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, 1H, 1H, 5H-octafluoropentyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (Meth) acrylate etc. are mentioned. Among these, monofunctional epoxy (meth) acrylate is preferable, and 2-hydroxy-3-phenoxypropyl (meth) acrylate is more preferable. The said polymeric compound (b) may be used independently and may be used in combination of 2 or more type.
In the present specification, the “(meth) acrylate” means acrylate or methacrylate, and the “epoxy (meth) acrylate” means that all epoxy groups in the epoxy compound are reacted with (meth) acrylic acid. Means a compound.

The monofunctional epoxy (meth) acrylate is obtained by reacting a monofunctional epoxy compound with (meth) acrylic acid, etc., and the structure derived from the monofunctional epoxy compound and the (meth) acrylic acid And derived structure.
Examples of the monofunctional epoxy compound include butyl glycidyl ether (for example, DY-BP (manufactured by Yokkaichi Synthesis)), 2-ethylhexyl glycidyl ether (for example, Epogosay 2EH (manufactured by Yokkaichi Synthesis)), allyl glycidyl ether ( For example, EX-101 (manufactured by Nagase ChemteX), 2-ethylhexyl glycidyl ether (for example, EX-121 (manufactured by Nagase ChemteX)), EO-modified phenol glycidyl ether (for example, EX-145 (Nagase ChemteX) ), EO-modified lauryl alcohol glycidyl ether (eg EX-171 (manufactured by Nagase ChemteX)), phenyl glycidyl ether (eg EX-141 (manufactured by Nagase ChemteX))), p-tert-butylphenylglycidyl Ete (E.g., manufactured by EX-146 (Nagase Chemtex Corporation)), dibromophenyl glycidyl ether (e.g., EX-147 (Nagase ChemteX Corporation)), and the like.
Moreover, as what is marketed among the said monofunctional epoxy (meth) acrylates, epoxy ester M-600A (made by Kyoeisha Chemical Co., Ltd.) etc. are mentioned, for example.

The preferable lower limit of the content of the polymerizable compound (b) in 100 parts by weight of the entire curable resin is 1 part by weight, and the preferable upper limit is 30 parts by weight. When the content of the polymerizable compound (b) is within this range, the storage modulus of the cured product at 25 ° C. can be easily set within the above-described range. The minimum with more preferable content of the said polymeric compound (b) is 5 weight part, and a more preferable upper limit is 25 weight part.

The sealing compound for liquid crystal display elements of the present invention is a polymerizable compound having a (meth) acryloyl group and an epoxy group in addition to the polymerizable compound (a) and the polymerizable compound (b) as the curable resin. (Hereinafter also referred to as “polymerizable compound (c)”). By containing the said polymeric compound (c), the sealing compound for liquid crystal display elements of this invention becomes more excellent in adhesiveness.

As said polymeric compound (c), the partial (meth) acryl modified epoxy resin etc. which are obtained by making the epoxy group of the part of the epoxy compound which has two or more epoxy groups react with (meth) acrylic acid etc. are mentioned, for example. It is done.
In the present specification, the “(meth) acryl” means acryl or methacryl.

As an epoxy compound used as the raw material of the polymerizable compound (c), for example, a bisphenol A type epoxy compound, a bisphenol F type epoxy compound, a bisphenol S type epoxy compound, a 2,2′-diallyl bisphenol A type epoxy compound, Hydrogenated bisphenol type epoxy compound, propylene oxide added bisphenol A type epoxy compound, resorcinol type epoxy compound, biphenyl type epoxy compound, sulfide type epoxy compound, diphenyl ether type epoxy compound, dicyclopentadiene type epoxy compound, naphthalene type epoxy compound, phenol novolac Type epoxy compound, orthocresol novolac type epoxy compound, dicyclopentadiene novolak type epoxy compound, biphenyl novolac type epoxy Shi compounds, naphthalene phenol novolac-type epoxy compounds, glycidyl amine type epoxy compounds, alkyl polyol type epoxy compound, a rubber-modified epoxy compounds, glycidyl ester compounds.

As what is marketed among the said polymeric compounds (c), KRM8287 (made by Daicel Ornex) is mentioned, for example.

As for content of the said polymeric compound (c), a preferable minimum is 5 weight part with respect to 100 weight part of whole curable resin, and a preferable upper limit is 50 weight part. When content of the said polymeric compound (c) is this range, the effect which improves adhesiveness can be exhibited more, suppressing generation | occurrence | production of liquid-crystal contamination. The minimum with more preferable content of the said polymeric compound (c) is 10 weight part, and a more preferable upper limit is 40 weight part.

The sealing agent for liquid crystal display elements of the present invention may further contain other polymerizable compounds as the polymerizable compound within a range not impairing the object of the present invention.

The other polymerizable compound is a polymerizable compound other than those contained in the polymerizable compound (a), the polymerizable compound (b), and the polymerizable compound (c). ) Acrylic compounds and polyfunctional epoxy compounds.

As the polyfunctional (meth) acrylic compound which is the other polymerizable compound, for example, a polyfunctional (meth) acrylic acid ester compound obtained by reacting (meth) acrylic acid with a compound having a hydroxyl group, (meth) Polyfunctional epoxy (meth) acrylate obtained by reacting acrylic acid with an epoxy compound, polyfunctional urethane (meth) acrylate obtained by reacting an isocyanate compound with a (meth) acrylic acid derivative having a hydroxyl group, etc. It is done.

Examples of the bifunctional compound among the polyfunctional (meth) acrylic acid ester compounds include those having no lactone ring-opening structure and acrylonitrile-butadiene structure. For example, 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, dipropyleneglyco Rudi (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, dimethylol dicyclopentadienyl di (meth) acrylate, ethylene oxide modified isocyanuric acid di (meth) acrylate, 2-hydroxy-3- (meth) acryloyloxypropyl ( (Meth) acrylate, carbonate diol di (meth) acrylate, polyether diol di (meth) acrylate, polyester diol di (meth) acrylate Over DOO, polybutadiene di (meth) acrylate.

Among the polyfunctional (meth) acrylic acid ester compounds, those having three or more functional groups include those having no lactone ring-opening structure and acrylonitrile-butadiene structure. For example, trimethylolpropane tri (meta) ) Acrylate, ethylene oxide-added trimethylolpropane tri (meth) acrylate, propylene oxide-added trimethylolpropane 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, tris (meth) acryloyloxyethyl phosphate, ditrimethylolpropane tetra (meth) acrylate, pen Pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate.

As said polyfunctional epoxy (meth) acrylate, what is bifunctional or more and does not have the ring-opening structure of lactone or an acrylonitrile-butadiene structure is mentioned, for example, an epoxy compound and (meth) acrylic acid are used. And those obtained by reacting in the presence of a basic catalyst according to a conventional method.

As an epoxy compound used as the raw material for synthesize | combining the said polyfunctional epoxy (meth) acrylate, the thing similar to the epoxy compound used as the raw material of the said polymeric compound (c) is mentioned.

As the polyfunctional urethane (meth) acrylate, for example, 2 equivalents of a (meth) acrylic acid derivative having a hydroxyl group is reacted with 1 equivalent of an isocyanate compound having two isocyanate groups in the presence of a catalytic amount of a tin-based compound. It can be obtained.

As an isocyanate compound used as the raw material of the polyfunctional urethane (meth) acrylate, for example, isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diphenylmethane-4 , 4'-diisocyanate (MDI), hydrogenated MDI, polymeric MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate, tolidine diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, tris (Isocyanate phenyl) thiophosphate, tetramethylxylylene diisocyanate, 1,6,11-undecane Li isocyanate, and the like.

Moreover, as an isocyanate compound used as the raw material of the polyfunctional urethane (meth) acrylate, for example, an excess of polyol such as ethylene glycol, propylene glycol, glycerin, sorbitol, trimethylolpropane, carbonate diol, polyether diol, polyester diol, and the like Chain-extended isocyanate compounds obtained by reaction with isocyanate compounds can also be used.

Examples of the (meth) acrylic acid derivative having a hydroxyl group, which is a raw material for the polyfunctional urethane (meth) acrylate, include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl ( Divalent alcohols such as (meth) acrylate, 2-hydroxybutyl (meth) acrylate, etc., ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol Mono (meth) acrylates, mono (meth) acrylates or di (meth) acrylates of trivalent alcohols such as trimethylolethane, trimethylolpropane, and glycerin, and epoxy (meth) acrylates such as bisphenol A type epoxy (meth) acrylates Acrylate, and the like.

Examples of the polyfunctional epoxy compound that is the other polymerizable compound include the same epoxy compounds as the raw material of the polymerizable compound (c).

The sealing agent for liquid crystal display elements of this invention contains a polymerization initiator and / or a thermosetting agent.
Examples of the polymerization initiator include radical polymerization initiators and cationic polymerization initiators.

Examples of the radical polymerization initiator include a thermal radical polymerization initiator that generates radicals by heating, a photo radical polymerization initiator that generates radicals by light irradiation, and the like.

Examples of the photo radical polymerization initiator include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, thioxanthones, and the like.

Examples of commercially available photo radical polymerization initiators include IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACURE OXE01, and Lucin TPO (all manufactured by BASF Methyl, Examples include benzoin ethyl ether and benzoin isopropyl ether (both manufactured by Tokyo Chemical Industry Co., Ltd.).

As said thermal radical polymerization initiator, what consists of an azo compound, an organic peroxide, etc. is mentioned, for example. Among these, a polymer azo initiator composed of a polymer azo compound is preferable.
In the present specification, the polymer azo initiator means a compound having an azo group and generating a radical capable of curing a (meth) acryloyloxy group by heat and having a number average molecular weight of 300 or more. .

The preferable lower limit of the number average molecular weight of the polymeric azo initiator is 1000, and the preferable upper limit is 300,000. When the number average molecular weight of the polymeric azo initiator is within this range, it can be easily mixed into the curable resin while preventing adverse effects on the liquid crystal. The more preferable lower limit of the number average molecular weight of the polymeric azo initiator is 5000, the more preferable upper limit is 100,000, the still more preferable lower limit is 10,000, and the still more preferable upper limit is 90,000.
In addition, in this specification, the said number average molecular weight is a value calculated | required by polystyrene conversion by measuring with gel permeation chromatography (GPC). Examples of the column for measuring the number average molecular weight in terms of polystyrene by GPC include Shodex LF-804 (manufactured by Showa Denko KK).

Examples of the polymer azo initiator include those having a structure in which a plurality of units such as polyalkylene oxide and polydimethylsiloxane are bonded via an azo group.
As the polymer azo initiator having a structure in which a plurality of units such as polyalkylene oxide are bonded via the azo group, those having a polyethylene oxide structure are preferable. Examples of such a polymeric azo initiator include polycondensates of 4,4′-azobis (4-cyanopentanoic acid) and polyalkylene glycol, and 4,4′-azobis (4-cyanopentanoic acid). Examples include polycondensates of polydimethylsiloxane having a terminal amino group, and specific examples include VPE-0201, VPE-0401, VPE-0601, VPS-0501, and VPS-1001 (all of which are Wako Pure Chemical Industries, Ltd.). Manufactured) and the like.
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 organic peroxide include ketone peroxide, peroxyketal, hydroperoxide, dialkyl peroxide, peroxyester, diacyl peroxide, and peroxydicarbonate.

As the cationic polymerization initiator, a photocationic polymerization initiator can be suitably used. The cationic photopolymerization initiator is not particularly limited as long as it generates a protonic acid or a Lewis acid by light irradiation, and may be of an ionic photoacid generation type or a nonionic photoacid generation type. It may be.
Examples of the cationic photopolymerization initiator include onium salts such as aromatic diazonium salts, aromatic halonium salts, and aromatic sulfonium salts, organometallic complexes such as iron-allene complexes, titanocene complexes, and arylsilanol-aluminum complexes. Is mentioned.

Examples of commercially available photocationic polymerization initiators include Adekaoptomer SP-150 and Adekaoptomer SP-170 (both manufactured by ADEKA).

The content of the polymerization initiator is preferably 0.1 parts by weight and preferably 30 parts by weight with respect to 100 parts by weight of the entire curable resin. When the content of the polymerization initiator is 0.1 parts by weight or more, the obtained sealing agent for liquid crystal display elements is more excellent in curability. When the content of the polymerization initiator is 30 parts by weight or less, the obtained sealing agent for liquid crystal display elements is more excellent in storage stability. A more preferable lower limit of the content of the polymerization initiator is 1 part by weight, a more preferable upper limit is 10 parts by weight, and a still more preferable upper limit is 5 parts by weight.

Examples of the thermosetting agent include organic acid hydrazides, imidazole derivatives, amine compounds, polyhydric phenol compounds, acid anhydrides, and the like. Among these, solid organic acid hydrazide is preferably used.

Examples of the solid organic acid hydrazide include 1,3-bis (hydrazinocarboethyl) -5-isopropylhydantoin, sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, malonic acid dihydrazide, and the like. Examples thereof include SDH, MDH, ADH (manufactured by Otsuka Chemical Co., Ltd.), Amicure VDH, Amicure VDH-J, Amicure UDH (all manufactured by Ajinomoto Fine Techno Co., Ltd.), and the like.

As for content of the said thermosetting agent, a preferable minimum is 1 weight part and a preferable upper limit is 50 weight part with respect to 100 weight part of whole curable resin. When the content of the thermosetting agent is 1 part by weight or more, the obtained sealing agent for liquid crystal display elements is more excellent in thermosetting. When the content of the thermosetting agent is 50 parts by weight or less, the obtained sealing agent for liquid crystal display elements is more excellent in applicability. The upper limit with more preferable content of the said thermosetting agent is 30 weight part.

It is preferable that the sealing compound for liquid crystal display elements of this invention contains a soft particle. When the liquid crystal display device is manufactured, the flexible particles serve as a barrier between the other sealing agent component and the liquid crystal, preventing the liquid crystal from being inserted into the sealing agent and the sealing agent from being eluted into the liquid crystal. Have a role to play.

The flexible particles preferably have a maximum particle size of 100% or more of the cell gap of the liquid crystal display element and 5 to 20 μm. The flexible particles can cause springback by using particles having a maximum particle size of 100% or more of the cell gap. However, by setting the maximum particle size of the flexible particles to 20 μm or less, gap defects due to springback can be prevented. A liquid crystal display element can be manufactured without causing it.
The cell gap of the liquid crystal display element is not limited because it varies depending on the display element, but the cell gap of a general liquid crystal display element is 2 to 10 μm.

The preferable lower limit of the maximum particle size of the flexible particles is 100% of the cell gap of the liquid crystal display element and 5 μm. That is, when the cell gap of the liquid crystal display element is 5 μm or less, the preferred lower limit of the maximum particle diameter of the flexible particles is 5 μm. When the cell gap of the liquid crystal display element exceeds 5 μm, the maximum particle diameter of the flexible particles is A preferred lower limit is 100% of the cell gap of the liquid crystal display element. The maximum particle diameter of the flexible particles is not less than 5 μm and 100% of the cell gap of the liquid crystal display element, which is the above lower limit value. It becomes.
In addition, from the viewpoint of suppressing a decrease in adhesiveness due to springback and a gap defect of the liquid crystal display element, a preferable upper limit of the maximum particle diameter of the flexible particles is 20 μm. A more preferable upper limit of the maximum particle size of the flexible particles is 15 μm.
Furthermore, the maximum particle diameter of the flexible particles is preferably 2.6 times or less of the cell gap from the viewpoint of suppressing a decrease in adhesion due to springback and a gap defect of the liquid crystal display element. A more preferable upper limit of the maximum particle diameter of the flexible particles is 2.2 times the cell gap, and a more preferable upper limit is 1.7 times the cell gap.
In the present specification, the maximum particle size of the flexible particles and the average particle size described below are values obtained by measuring the particles before blending with the sealant using a laser diffraction particle size distribution measuring device. means. As the laser diffraction type distribution measuring device, Mastersizer 2000 (manufactured by Malvern) or the like can be used.

In the flexible particles, the content ratio of particles having a particle diameter of 5 μm or more in the particle size distribution of the flexible particles measured by the laser diffraction type distribution measuring device is preferably 60% or more by volume frequency. When the content ratio of the particles having a particle diameter of 5 μm or more is 60% or more in terms of volume frequency, the effect of suppressing seal break and liquid crystal contamination is excellent. The content ratio of particles having a particle diameter of 5 μm or more is more preferably 80% or more.

The flexible particles contain 100% or more of the cell gap of the liquid crystal display element by 70% or more of the particle size distribution in the entire flexible particles from the viewpoint of further exerting the effect of suppressing the occurrence of seal break and liquid crystal contamination. It is preferable that the liquid crystal display element is composed only of particles having a cell gap of 100% or more.

A preferable lower limit of the average particle diameter of the flexible particles is 2 μm. When the average particle diameter of the flexible particles is 2 μm or more, the effect of suppressing seal break and liquid crystal contamination is excellent. A more preferable lower limit of the average particle diameter of the flexible particles is 4 μm.
Further, from the viewpoint of suppressing a decrease in adhesiveness due to springback and a gap defect of the liquid crystal display element, a preferable upper limit of the average particle diameter of the flexible particles is 15 μm. A more preferable upper limit of the average particle diameter of the flexible particles is 12 μm.

As the soft particles, two or more kinds of soft particles having different maximum particle diameters may be mixed and used. That is, a soft particle having a maximum particle diameter of less than 100% of the cell gap of the liquid crystal display element and a soft particle having a maximum particle diameter of 100% or more of the cell gap of the liquid crystal display element may be mixed and used.

The coefficient of variation (hereinafter also referred to as CV value) of the flexible particles is preferably 30% or less from the viewpoint of suppressing cell gap defects. The CV value of the particle diameter of the flexible particles is more preferably 28% or less.
In the present specification, the CV value of the particle diameter is a numerical value obtained by the following formula.
CV value of particle diameter (%) = (standard deviation of particle diameter / average particle diameter) × 100

Even if the above-mentioned flexible particles are those having a maximum particle size, an average particle size, or a CV value outside the above-mentioned ranges, the maximum particle size, the average particle size, or the CV value is set within the above-mentioned range by classification. Can do. In addition, flexible particles having a particle size of less than 100% of the cell gap of the liquid crystal display element do not contribute to the suppression of the occurrence of seal break and liquid crystal contamination, and may increase the thixo value when blended with a sealant. It is preferable to remove by classification.
Examples of the method for classifying the flexible particles include wet classification and dry classification. Of these, wet classification is preferable, and wet sieving classification is more preferable.

Examples of the flexible particles include silicone particles, vinyl particles, urethane particles, fluorine particles, and nitrile particles. Of these, silicone particles and vinyl particles are preferable.

The silicone-based particles are preferably silicone rubber particles from the viewpoint of dispersibility in the resin.
Examples of commercially available silicone particles include KMP-594, KMP-597, KMP-598, KMP-600, KMP-601, KMP-602 (manufactured by Shin-Etsu Chemical Co., Ltd.), Trefil E- 506S, EP-9215 (manufactured by Toray Dow Corning Co., Ltd.) and the like, and these can be classified and used. The said silicone type particle | grains may be used independently and 2 or more types may be used together.

(Meth) acrylic particles are preferably used as the vinyl particles.
The (meth) acrylic particles can be obtained by polymerizing monomers as raw materials by a known method. Specifically, for example, a method in which a monomer is suspension-polymerized in the presence of a radical polymerization initiator, and a seed particle is swollen by absorbing the monomer into a non-crosslinked seed particle in the presence of a radical polymerization initiator. And a seed polymerization method.

Examples of the monomer that is a raw material for forming the (meth) acrylic particles include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and hexyl (meth). Alkyl (meth) such as acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, etc. ) Acrylates, oxygen-containing (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, glycerol (meth) acrylate, polyoxyethylene (meth) acrylate, glycidyl (meth) acrylate, etc. And, (meth) nitrile and containing monomers such as acrylonitrile, trifluoromethyl (meth) acrylate, monofunctional monomer such as a fluorine-containing (meth) acrylates such as pentafluoroethyl (meth) acrylate. Among these, alkyl (meth) acrylates are preferable because the Tg of the homopolymer is low and the deformation amount when a 1 g load is applied can be increased.

Moreover, in order to give a crosslinked structure, tetramethylol methane tetra (meth) acrylate, tetramethylol methane tri (meth) acrylate, tetramethylol methane di (meth) acrylate, trimethylol propane tri (meth) acrylate, dipentaerythritol hexa ( (Meth) acrylate, dipentaerythritol penta (meth) acrylate, glycerol tri (meth) acrylate, glycerol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, ( Poly) tetramethylene di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, isocyanuric acid skeleton tri (meth) It may be used polyfunctional monomers acrylate. Especially, since the molecular weight between cross-linking points is large and the deformation amount when a 1 g load is applied can be increased, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, ( Poly) tetramethylene di (meth) acrylate, 1,4-butanediol di (meth) acrylate, and 1,6-hexanediol di (meth) acrylate are preferred.

With respect to the use amount of the crosslinkable monomer, the preferable lower limit is 1% by weight and the preferable upper limit is 90% by weight in the whole monomer as a raw material for forming the (meth) acrylic particles. When the amount of the crosslinkable monomer used is 1% by weight or more, the solvent resistance is improved, and when kneaded with various sealant raw materials, problems such as swelling do not occur and the particles are easily dispersed uniformly. When the amount of the crosslinkable monomer used is 90% by weight or less, the recovery rate can be lowered, and problems such as springback are less likely to occur. A more preferable lower limit of the amount of the crosslinkable monomer used is 3% by weight, and a more preferable upper limit is 80% by weight.

In addition to these acrylic monomers, styrene monomers such as styrene and α-methylstyrene, vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, and propyl vinyl ether, vinyl acetate, vinyl butyrate, and laurin. Acid vinyl esters such as vinyl acid and vinyl stearate, unsaturated hydrocarbons such as ethylene, propylene, isoprene and butadiene, halogen-containing monomers such as vinyl chloride, vinyl fluoride and chlorostyrene, triallyl (iso ) Using monomers such as cyanurate, triallyl trimellitate, divinylbenzene, diallylphthalate, diallylacrylamide, diallyl ether, γ- (meth) acryloxypropyltrimethoxysilane, trimethoxysilylstyrene, vinyltrimethoxysilane Good .

Further, as the vinyl particles, for example, polydivinylbenzene particles, polychloroprene particles, butadiene rubber particles and the like may be used.

Examples of commercially available urethane-based particles include Art Pearl (manufactured by Negami Kogyo Co., Ltd.), Dimic Beads (manufactured by Dainichi Seika Kogyo Co., Ltd.), and the like, which can be classified and used. .

From the viewpoint of suppressing a decrease in adhesiveness of the obtained sealing agent for liquid crystal display elements and a gap defect of the obtained liquid crystal display element, the preferred lower limit of the hardness of the flexible particles is 10, and the preferred upper limit is 50. The more preferable lower limit of the hardness of the soft particles is 20, and the more preferable upper limit is 40.
In addition, in this specification, the hardness of the said flexible particle means the durometer A hardness measured by the method based on JISK6253.

The preferable lower limit of the content of the flexible particles is 15% by weight with respect to the entire liquid crystal display element sealing agent. When the content of the flexible particles is 15% by weight or more, the effect of suppressing the occurrence of seal break and liquid crystal contamination is excellent. The minimum with more preferable content of the said flexible particle | grain is 20 weight%.
Further, from the viewpoint of suppressing a decrease in adhesiveness due to springback and a gap defect of the liquid crystal display element, the upper limit of the content of the flexible particles is preferably 50% by weight with respect to the entire liquid crystal display element sealing agent. The upper limit with more preferable content of the said flexible particle | grain is 40 weight%.

The sealing agent for liquid crystal display elements of the present invention may contain a filler for the purpose of improving the viscosity, further improving the adhesion due to the stress dispersion effect, improving the linear expansion coefficient, improving the moisture resistance of the cured product, and the like. preferable.

Examples of the filler include silica, talc, glass beads, asbestos, gypsum, diatomaceous earth, smectite, bentonite, montmorillonite, sericite, activated clay, alumina, zinc oxide, iron oxide, magnesium oxide, tin oxide, titanium oxide, Organic fillers such as calcium carbonate, magnesium carbonate, magnesium hydroxide, aluminum hydroxide, aluminum nitride, silicon nitride, barium sulfate, and calcium silicate, and organic materials such as polyester fine particles, polyurethane fine particles, vinyl polymer fine particles, and acrylic polymer fine particles A filler is mentioned.

The content of the filler is preferably 10 parts by weight with respect to 100 parts by weight of the entire curable resin, and 70 parts by weight with respect to the preferable upper limit. When content of the said filler is this range, effects, such as an adhesive improvement, can be exhibited more, suppressing deterioration, such as applicability | paintability. The minimum with more preferable content of the said filler is 20 weight part, and a more preferable upper limit is 60 weight part.

The sealing agent for liquid crystal display elements of the present invention preferably contains a silane coupling agent for the purpose of further improving the adhesiveness. The silane coupling agent mainly has a role as an adhesion assistant for favorably bonding the sealing agent and the substrate.
As the silane coupling agent, for example, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane and the like are preferably used.

The content of the silane coupling agent is preferably 0.1 parts by weight and preferably 20 parts by weight with respect to 100 parts by weight of the entire curable resin. When the content of the silane coupling agent is within this range, the effect of improving the adhesiveness can be further exhibited while suppressing the occurrence of liquid crystal contamination. The minimum with more preferable content of the said silane coupling agent is 0.5 weight part, and a more preferable upper limit is 10 weight part.

The sealing agent for liquid crystal display elements of the present 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 agent.

Examples of the light-shielding agent include iron oxide, titanium black, aniline black, cyanine black, fullerene, carbon black, and resin-coated carbon black. Of these, titanium black is preferable.

The titanium black is a substance having a higher transmittance in the vicinity of the ultraviolet region, particularly for light with a wavelength of 370 to 450 nm, compared to the average transmittance for light with a wavelength of 300 to 800 nm. That is, the above-described titanium black sufficiently shields light having a wavelength in the visible light region, thereby providing a light shielding property to the sealing agent for liquid crystal display elements of the present invention, while transmitting light having a wavelength in the vicinity of the ultraviolet region. A shading agent. The light shielding agent contained in the liquid crystal display element sealant of the present invention is preferably a highly insulating material, and titanium black is also preferred as the highly insulating light shielding agent.

The above-mentioned titanium black exhibits a sufficient effect even if it is not surface-treated, but the surface is treated with an organic component such as a coupling agent, silicon oxide, titanium oxide, germanium oxide, aluminum oxide, oxidized Surface-treated titanium black such as those coated with an inorganic component such as zirconium or magnesium oxide can also be used. Especially, what is processed with the organic component is preferable at the point which can improve insulation more.
In addition, the liquid crystal display element produced using the sealing agent for liquid crystal display elements of the present invention containing the above-described titanium black as a light-shielding agent has a sufficient light-shielding property, and thus has high contrast without light leakage. A liquid crystal display element having excellent image display quality can be realized.

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

The preferable lower limit of the specific surface area of the titanium black is 13 m ² / g, the preferable upper limit is 30 m ² / g, the more preferable lower limit is 15 m ² / g, and the more preferable upper limit is 25 m ² / g.
Further, the preferred lower limit of the volume resistance of the titanium black is 0.5 Ω · cm, the preferred upper limit is 3 Ω · cm, the more preferred lower limit is 1 Ω · cm, and the more preferred upper limit is 2.5 Ω · cm.

The primary particle diameter of the light-shielding agent is not particularly limited as long as it is not more than the distance between the substrates of the liquid crystal display element, but the preferred lower limit is 1 nm and the preferred upper limit is 5 μm. When the primary particle diameter of the light-shielding agent is within this range, the viscosity and thixotropy of the obtained sealing agent for liquid crystal display elements are not greatly increased, and the coating property is excellent. The more preferable lower limit of the primary particle diameter of the light shielding agent is 5 nm, the more preferable upper limit is 200 nm, the still more preferable lower limit is 10 nm, and the still more preferable upper limit is 100 nm.
The primary particle size of the light-shielding agent can be measured using a particle size distribution meter (for example, “NICOMP 380ZLS” manufactured by PARTICLE SIZING SYSTEMS).

The preferable lower limit of the content of the light-shielding agent in 100 parts by weight of the sealant for liquid crystal display elements of the present invention is 5 parts by weight, and the preferable upper limit is 80 parts by weight. When the content of the light-shielding agent is within this range, the effect of improving the light-shielding property is exhibited without lowering the adhesiveness, strength after curing, and drawing property of the obtained sealing agent for liquid crystal display elements. it can. The more preferable lower limit of the content of the light shielding agent is 10 parts by weight, the more preferable upper limit is 70 parts by weight, the still more preferable lower limit is 30 parts by weight, and the still more preferable upper limit is 60 parts by weight.

The sealing agent for liquid crystal display elements of the present invention is further added with a stress relaxation agent, reactive diluent, thixotropic agent, spacer, curing accelerator, antifoaming agent, leveling agent, polymerization inhibitor, etc., if necessary. An agent may be contained.

As a method for producing the sealing agent for liquid crystal display elements of the present invention, for example, using a mixer such as a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, a three roll, a curable resin, and a polymerization Examples thereof include a method of mixing an initiator and / or a thermosetting agent and an additive such as a silane coupling agent added as necessary.

As for the sealing compound for liquid crystal display elements of this invention, the preferable upper limit of the glass transition temperature of hardened | cured material is 100 degreeC. By the said glass transition temperature being 100 degrees C or less, the sealing compound for liquid crystal display elements of this invention will become more excellent in adhesiveness. A more preferable upper limit of the glass transition temperature is 80 ° C., and a more preferable upper limit is 60 ° C.
Moreover, from a viewpoint of moisture permeation prevention properties, the preferable lower limit of the glass transition temperature of the cured product is 40 ° C, and the more preferable lower limit is 46 ° C.
In the present specification, the “glass transition temperature” means a temperature at which a maximum due to micro-Brownian motion appears among the maximum of loss tangent (tan δ) obtained by dynamic viscoelasticity measurement. The glass transition temperature can be measured by a conventionally known method using a viscoelasticity measuring device or the like.
Further, as the cured product for measuring the glass transition temperature, a cured product obtained by curing the sealing agent in the same manner as the cured product for measuring the storage elastic modulus is used.

A vertical conducting material can be produced by blending conductive fine particles with the liquid crystal display element sealant of the present invention. Such a vertical conduction material containing the sealing agent for liquid crystal display elements of the present invention and conductive fine particles is also one aspect of the present invention.

As the conductive fine particles, a metal ball, a resin fine particle formed with a conductive metal layer on the surface, or the like can be used. Among them, the one in which the conductive metal layer is formed on the surface of the resin fine particles is preferable because the conductive connection is possible without damaging the transparent substrate due to the excellent elasticity of the resin fine particles.

The liquid crystal display element using the sealing agent for liquid crystal display elements of this invention or the vertical conduction material of this invention is also one of this invention.

The sealing agent 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 for producing the liquid crystal display element of the present invention by the liquid crystal dropping method, specifically, for example, a rectangular seal pattern is formed on the substrate by screen printing, dispenser application, etc. of the liquid crystal display element sealant of the present invention. A step of applying liquid crystal microdroplets to the entire surface of the transparent substrate in an uncured state of the sealant for the liquid crystal display element of the present invention, and immediately superimposing another substrate; and Examples of the method include a step of irradiating a seal pattern portion such as a sealing agent for liquid crystal display elements with light such as ultraviolet rays to temporarily cure the sealing agent, and a step of heating and temporarily curing the temporarily cured sealing agent. It is done.

As the substrate, a flexible substrate is suitable.
Examples of the flexible substrate include plastic substrates using polyethylene terephthalate, polyester, poly (meth) acrylate, polycarbonate, polyether sulfone, and the like. Moreover, the sealing compound for liquid crystal display elements of this invention may be used when adhere | attaching a normal glass substrate.
The substrate is usually formed with a transparent electrode made of indium oxide or the like, an alignment film made of polyimide or the like, an inorganic ion shielding film, or the like.

ADVANTAGE OF THE INVENTION According to this invention, the sealing compound for liquid crystal display elements which is excellent in adhesiveness and moisture permeability prevention property can be provided. Moreover, according to this invention, the vertical conduction material and liquid crystal display element which use this sealing compound for liquid crystal display elements can be provided.

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

(Comparative Example 1)
75 parts by weight of caprolactone-modified bisphenol A type epoxy acrylate (manufactured by Daicel Ornex, "EBECRYL3708") as the polymerizable compound (a), and 2-hydroxy-3-phenoxypropyl acrylate (manufactured by Kyoeisha Chemical Co., Ltd.) as the polymerizable compound (b) , "Epoxy ester M-600A") 10 parts by weight, 15 parts by weight of partially acrylic modified bisphenol E type epoxy resin (manufactured by Daicel Ornex Co., Ltd., "KRM8287") as polymerizable compound (c), 1 as a radical photopolymerization initiator 1 part by weight of-(4- (phenylthio) phenyl) -1,2-octanedione-2- (O-benzoyloxime) (manufactured by BASF, "IRGACURE OXE01"), malonic acid dihydrazide (Otsuka Chemical Co., Ltd.) as a thermosetting agent Manufactured, "MDH") 1 part by weight, Silica (“Admafine SO-C2”, 50 parts by weight) as filler and 3-glycidoxypropyltrimethoxysilane (“KBM-403”, manufactured by Shin-Etsu Chemical Co., Ltd.) 1 as a silane coupling agent Part by weight and 10 parts by weight of core-shell acrylate copolymer fine particles (Zeon Kasei Co., Ltd., “F351”) as a stress relaxation agent are mixed using a planetary stirrer (Sinky Co., Ltd., “Awatori Kentaro”). After that, a sealing agent for liquid crystal display elements was prepared by further mixing using three rolls.
About the obtained sealing agent for a liquid crystal display element, a 100 mW / cm ² ultraviolet ray (wavelength 365 nm) was irradiated using a metal halide lamp for 30 seconds, and then cured by heating at 120 ° C. for 1 hour. Using a viscoelasticity measuring device ("DVA-200" manufactured by IT Measurement Control Co., Ltd.), at 25 ° C, a test piece width of 5 mm, a thickness of 0.35 mm, a grip width of 25 mm, and a heating rate of 10 ° C / minute frequency of 10 Hz. The storage elastic modulus measured at 1 was 1.0 GPa, and the storage elastic modulus measured at 60 ° C. under the same conditions was 0.04 GPa.

(Example 4 and Comparative Examples 2 to 11)
In the same manner as in Comparative Example 1, the materials having the blending ratios listed in Table 1 were mixed by stirring to prepare sealants for liquid crystal display elements of Example 4 and Comparative Examples 2 to 11.
About each obtained sealing compound for liquid crystal display elements, hardened | cured material was produced similarly to the comparative example 1, and about each obtained hardened | cured material, the storage elastic modulus in 25 degreeC and 60 degreeC measured similarly to the comparative example 1 Are shown in Table 1.

<Evaluation>
The following evaluation was performed about each sealing compound for liquid crystal display elements obtained by the Example and the comparative example. The results are shown in Table 1.

(Glass-transition temperature)
Each sealant for liquid crystal display elements obtained in the examples and comparative examples was irradiated with 100 mW / cm ² ultraviolet rays (wavelength 365 nm) for 30 seconds using a metal halide lamp, and then heated at 120 ° C. for 1 hour to a thickness of 300 μm. A film was prepared as a test piece. About the obtained test piece, using a dynamic viscoelasticity measuring apparatus (IT measurement control company make, "DVA-200"), dynamic viscoelasticity is measured in -80 to 200 degreeC and 10 Hz, loss tangent ( The maximum temperature of tan δ) was determined as the glass transition temperature.

(Adhesiveness)
Take each of the obtained sealing agents for liquid crystal display elements obtained in Examples and Comparative Examples in the center of a polyethylene terephthalate (PET) film of 20 mm × 50 mm (manufactured by Lintec Corporation, “PET5011”). The PET 5011 having the same size was overlaid on the liquid crystal to spread the liquid crystal display element sealant. In this state, 100 mW / cm ² of ultraviolet rays (wavelength 365 nm) was irradiated for 30 seconds using a metal halide lamp, and then heated at 120 ° C. for 1 hour to prepare an adhesion test piece. The adhesive strength of the obtained adhesion test piece was measured using EZgraph (manufactured by Shimadzu Corporation). Moreover, it replaced with PET5011, the glass substrate was used, the adhesion test piece was produced similarly, and the adhesive strength was measured.
“◯” indicates that the adhesive strength was 1 N / cm or more, “Δ” indicates that the adhesive strength was 0.5 N / cm or more and less than 1 N / cm, and the adhesive strength was less than 0.5 N / cm. The adhesiveness with respect to PET film was evaluated by making a thing "x".

(Moisture permeability prevention)
Each of the liquid crystal display element sealing agents obtained in Examples and Comparative Examples was applied to a smooth release film with a coater to a thickness of 200 to 300 μm, and 100 mW / cm ² of ultraviolet rays (wavelength) using a metal halide lamp. 365 nm) for 30 seconds, and then heated at 120 ° C. for 1 hour to obtain a cured film for measuring moisture permeability. A moisture permeability test cup was prepared by a method according to JIS Z 0208 for moisture-proof packaging materials (cup method), and the obtained cured film for moisture permeability measurement was attached, at a temperature of 60 ° C. and a humidity of 90% RH. The moisture permeability was measured by putting in a constant temperature and humidity oven. The case where the value of the resulting moisture permeability is less than ^70g / m 2 · 24hr "○", the case was less than ^70g / m 2 · 24hr or more 100g ^/ m 2 · 24hr "△", 100 g / m ^The case where it was ² · 24 hr or more was evaluated as “×” to evaluate moisture permeability.

(Low liquid crystal contamination)
1 part by weight of spacer microparticles (manufactured by Sekisui Chemical Co., Ltd., “Micropearl SI-H050”) is dispersed in 100 parts by weight of the sealant for each liquid crystal display element obtained in Examples and Comparative Examples, and two rubbed orientations are obtained. A dispenser was applied to one of the film and the substrate with a transparent electrode (length 75 mm, width 75 mm, thickness 0.7 mm) with a line width of 1 mm of the sealing agent so that the display portion was 45 mm × 55 mm.
Subsequently, liquid droplets (manufactured by Chisso Corporation, "JC-5004LA") are dropped onto the entire surface of the sealing agent frame of the substrate with a transparent electrode, and the other color filter substrate with a transparent electrode is immediately bonded to the seal. The agent part was irradiated with 100 mW / cm ² ultraviolet rays (wavelength 365 nm) for 30 seconds using a metal halide lamp, and then heated at 120 ° C. for 1 hour to obtain a liquid crystal display element.
About the obtained liquid crystal display element, after performing the operation test for 100 hours, the liquid crystal alignment disorder of the sealant vicinity after making it into a voltage application state at 80 degreeC for 1000 hours was confirmed visually.
The alignment disorder is determined by the color unevenness of the display part. Depending on the degree of color unevenness, “◎” indicates that there is no color unevenness, “○” indicates that the color unevenness is slight, and “color unevenness”. The low liquid crystal contamination property was evaluated with “△” when there was a little, and “×” when there was considerable color unevenness.
In addition, the liquid crystal display elements with the evaluations “◎” and “O” are at a level where there is no problem in practical use, and “Δ” is a level that may cause a problem depending on the display design of the liquid crystal display element. "X" is a level that cannot be practically used.

(Impact resistance of liquid crystal display elements)
About each liquid crystal display element sealing agent obtained in Examples and Comparative Examples, 10 liquid crystal display elements (10 cells) were produced in the same manner as in the above “(low liquid crystal contamination)”, and each liquid crystal display element. Was dropped from a height of 2 m. After the drop test, “◯” indicates that no liquid crystal leaks due to peeling or cracking in all cells, “△” indicates that there is liquid crystal leak in a liquid crystal display element of 1 cell or more and less than 5 cells, and liquid crystal of 5 cells or more. The impact resistance of the liquid crystal display element was evaluated with “×” when the liquid crystal leaked in the display element.

ADVANTAGE OF THE INVENTION According to this invention, the sealing compound for liquid crystal display elements which is excellent in adhesiveness and moisture permeability prevention property can be provided. Moreover, according to this invention, the vertical conduction material and liquid crystal display element which use this sealing compound for liquid crystal display elements can be provided.

Claims (9)

A sealing agent for a liquid crystal display element comprising a curable resin and a polymerization initiator and / or a thermosetting agent,
A sealant for a liquid crystal display device, wherein the cured product has a storage elastic modulus at 25 ° C of 0.8 to 3.0 GPa and a glass transition temperature of the cured product of 46 ° C or higher and lower than 60 ° C. The sealing agent for liquid crystal display elements according to claim 1, wherein the cured product has a storage elastic modulus at 60 ° C of 0.04 GPa or more. The curable resin contains a polymerizable compound having one or more polymerizable functional groups and one or more lactone ring-opening structures and / or one or more acrylonitrile-butadiene structures in one molecule. The sealing agent for liquid crystal display elements of Claim 1 or 2. The curable resin contains a monofunctional polymerizable compound having one polymerizable functional group in one molecule and having no lactone ring-opening structure and acrylonitrile-butadiene structure. Item 4. A sealing agent for liquid crystal display elements according to item 3. The content of the monofunctional polymerizable compound having one polymerizable functional group per molecule in 100 parts by weight of the curable resin and having no ring-opening structure of lactone and no acrylonitrile-butadiene structure is 1 The sealing agent for liquid crystal display elements according to claim 4, which is ˜30 weight parts. 6. The sealing agent for a liquid crystal display element according to claim 1, comprising flexible particles. The light-shielding agent is contained, The sealing compound for liquid crystal display elements of Claim 1, 2, 3, 4, 5 or 6 characterized by the above-mentioned. A vertical conduction material comprising the sealing agent for a liquid crystal display element according to claim 1, 2, 3, 4, 5, 6 or 7, and conductive fine particles. A liquid crystal display element comprising the sealant for a liquid crystal display element according to claim 1, 2, 3, 4, 5, 6 or 7, or the vertical conduction material according to claim 8.