CN102007447A - Sealant for liquid crystal dropping process, sealant for liquid crystal panel, upper and lower conduction material, and liquid crystal display element - Google Patents

Abstract

The present invention aims to provide a sealing agent for a liquid crystal dropping process that can produce a high-quality image with minimal color unevenness when a liquid crystal display element is manufactured using a dropping process. The present invention provides a sealing agent for a liquid crystal dropping process comprising a resin having a (meth)acryloyl group and a polymeric azo initiator.

Description

Sealant for liquid crystal dropping process, sealant for liquid crystal panel, upper and lower conduction material, and liquid crystal display element

technical field

The present invention relates to a sealing compound for a liquid crystal dropping method capable of producing a high-quality image with few color unevenness when a liquid crystal display device is manufactured by a dropping method. Moreover, it is related with the sealing agent for liquid crystal panels which can manufacture the liquid crystal display element of the high-quality image with little color unevenness when manufacturing a liquid crystal display device by the vacuum injection method.

Background technique

At present, liquid crystal display elements such as liquid crystal display units are manufactured using the following process called vacuum injection method. The method is to make two transparent substrates with electrodes facing each other with a predetermined interval, and seal them with a sealant. A cell is formed around the cell, liquid crystal is injected into the cell from a liquid crystal injection port provided in a part thereof, and the liquid crystal injection port is sealed with a sealant or a sealant.

In the vacuum injection method, first, on either of the two transparent substrates with electrodes, a seal pattern with a liquid crystal injection port is formed by screen printing using a thermosetting sealant, and prebaked at 60 to 100°C to make The solvent in the sealant dries. Next, insert the spacer, and make the two substrates face each other, align them to make the two stick together, perform hot pressing at 110-220°C for 10-90 minutes, adjust the gap near the seal, and heat them in an oven at 110°C. Heat at ~220°C for 10-120 minutes to make the sealant undergo main curing. Next, liquid crystal is injected from the liquid crystal injection port, and finally the liquid crystal injection port is sealed with a sealing agent to manufacture a liquid crystal display element.

However, in recent years, the methods of manufacturing liquid crystal display devices such as liquid crystal display units are gradually changing from the above-mentioned vacuum injection method to those disclosed in, for example, Patent Document 1 and Patent Document 2, from the viewpoints of shortening tact time and optimizing the amount of liquid crystals used. A liquid crystal called a drop method using a sealant composed of a light-heat curable resin composition containing a photocurable acrylic resin and a photopolymerization initiator, and a thermosetting epoxy resin and a thermal polymerization initiator. drip way.

In the liquid crystal dropping method, first, a seal pattern is formed on one of the two substrates with electrodes. Then, in the state where the sealant is not cured, tiny liquid crystal drops are dropped on the entire frame of the substrate, and the other substrate is superimposed in vacuum, and after returning to normal pressure, the acrylic resin is cured by irradiating ultraviolet rays to the sealed part (pre-curing). process). Thereafter, the epoxy resin was cured by heating to produce a liquid crystal display element.

However, various mobile devices equipped with liquid crystal panels, such as mobile phones and portable game consoles, are now widely used, and miniaturization of devices has become the most urgent research topic. As a method of miniaturization, narrow-frame (narrow-frame) of the liquid crystal display part can be mentioned, for example, the position of the sealing part is configured under the black matrix (hereinafter also referred to as narrow-frame design).

However, when the dripping process is performed with a narrow frame design, there are places where light cannot be irradiated in the sealing part due to the black matrix, so there are parts of uncured acrylic resin that are not sufficiently irradiated with light, and uncured parts after the pre-curing process The acrylic resin dissolves, contaminates the liquid crystal, and causes uneven display of the liquid crystal.

In addition, in order to reliably irradiate light to the sealing part under the black matrix, a method of irradiating light from the back of the substrate, that is, the array side, has also been proposed. However, there are also metal wirings, transistors, etc. out of reach.

In response to such a problem, in order to surely cure uncured acrylic resin after light irradiation, a method of using a sealant containing a low-molecular-weight peroxide or an azo compound as a component for thermally curing the acrylic resin has also been proposed. If such a sealant is used, the acrylic resin that has not been cured in the pre-curing step can be cured by heating during liquid crystal annealing. However, there is a problem that a liquid crystal display element with a high-quality image cannot be obtained because low-molecular-weight peroxides or azo compounds are eluted into the liquid crystal to cause color unevenness around the sealing portion.

On the other hand, when a liquid crystal display device is manufactured by the vacuum injection method which is a conventional technique, there exists the same subject as the case of the liquid crystal dropping method mentioned above. That is, when a liquid crystal display device is manufactured by the vacuum injection method, the sealing agent for liquid crystal panels used for liquid crystal sealing contacts a liquid crystal in the uncured state. Here, when sufficient light is not irradiated to the sealing agent for liquid crystal panels, color unevenness will still arise around the sealing part, and the liquid crystal display element of a high-quality image cannot be obtained.

Patent Document 1: Japanese Patent Laid-Open No. 2001-133794

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

Contents of the invention

In view of the above circumstances, the object of the present invention is to provide a sealing compound for a liquid crystal dropping process capable of producing a liquid crystal display element having a high-quality image with few color unevenness even when a liquid crystal display element is produced by a dropping process. In addition, there is also provided a sealing agent for a liquid crystal panel capable of producing a liquid crystal display element having a high-quality image with less color unevenness when a liquid crystal display device is produced by a vacuum injection method.

The present invention provides a liquid crystal dropping method sealing agent containing a resin having a (meth)acryloyl group and a polymer azo initiator.

The invention provides a liquid crystal panel sealing agent containing a resin having a (meth)acryloyl group and a polymer azo initiator.

The present invention is described in detail below.

As a result of intensive research by the present inventors, it was found that the azo initiator itself has no adverse effect on the liquid crystal when the sealant for liquid crystal dropping process containing a resin having a (meth)acryloyl group and a polymer azo initiator is thermally cured, In addition, by curing the uncured resin having a (meth)acryloyl group, a liquid crystal display element with less color unevenness and a high-quality image can be produced, and the present invention has been completed.

The sealing compound for liquid crystal dropping methods of this invention contains a polymeric azo initiator.

In the sealant for liquid crystal dropping process of the present invention, by using such an initiator, even the sealing portion where light is not irradiated by a black matrix etc. can be reliably cured by heat, so the occurrence of liquid crystal is extremely small. pollute.

The polymeric azo initiator used in this specification refers to a compound having an azo group and having a molecular weight of 300 or more capable of curing (meth)acryloyl groups by heat and generating radicals.

Furthermore, the above-mentioned polymeric azo initiators are usually also decomposed by light irradiation to generate radicals, so they can also function as photoradical initiators.

The preferable lower limit of the number average molecular weight of the said high molecular weight azo initiator is 1000, and a preferable upper limit is 300,000. When the number average molecular weight of the polymeric azo initiator is less than 1,000, the polymeric azo initiator may adversely affect liquid crystals, and when it exceeds 300,000, it may be difficult to mix with a resin having a (meth)acryloyl group. The number average molecular weight of the above polymeric azo initiator has a more preferable lower limit of 5,000, a more preferable upper limit of 100,000, a most preferable lower limit of 10,000, and a most preferable upper limit of 90,000.

The preferable lower limit of the 10-hour half-life temperature of the said polymeric azo initiator is 50 degreeC, and a preferable upper limit is 90 degreeC. When the 10-hour half-life temperature of the said high molecular weight azo compound is less than 50 degreeC, the storage stability of the sealing compound for liquid crystal dropping methods obtained may worsen. When the 10-hour half-life temperature of the polymeric azo compound exceeds 90° C., high temperature and long time are required for curing of the sealing compound for liquid crystal dropping methods of the present invention, which may affect panel productivity.

Examples of the polymeric azo initiator include those having a structure in which units such as polydimethylsiloxane and polyoxyalkylene are bonded via an azo group.

A structure having a polyethylene oxide structure is preferable as a structure in which a plurality of units such as polyoxyalkylene is bonded.

Examples of such polymeric azo initiators include polycondensates of 4,4'-azobis(4-cyanovaleric acid) and polyalkylene glycol, or 4,4'-azo Condensation products of bis(4-cyanovaleric acid) and polydimethylsiloxane having an amino group at the end, etc., specific examples include VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS- 1001 (both are manufactured by Wako Pure Chemical Industries, Ltd.), etc.

In addition, as the polymeric azo compound, a polymeric azo compound represented by the following general formula (I) described in JP-A-2008-50572 or JP-A-2003-12784 can be preferably used.

In formula (I), R ¹² , R ¹³ , R ²² and R ²³ each independently represent an alkyl or cyano group with 1 to 10 carbon atoms, a and b each independently represent a number of 0 to 4, and A ¹¹ and A ¹² are polymer chains, and Y ¹¹ and Y ¹² are each independently -CO-O-, -O-CO-, -NH-CO-, -CO-NH-, -O- or -S-.

In the above general formula (I), the alkyl groups having 1 to 10 carbon atoms represented by R ¹² , R ¹³ , R ²² and R ²³ include methyl, ethyl, propyl, isopropyl, and butyl , sec-butyl, tert-butyl, isobutyl, pentyl, isopentyl, tert-pentyl, hexyl, cyclohexyl, cyclohexylmethyl, cyclohexylethyl, heptyl, isoheptyl, tert-heptyl, n-octyl, isooctyl, t-octyl, 2-ethylhexyl, n-nonyl, n-decyl, etc.

In the above general formula (I), the polymer chains represented by ^A11 and ^A12 are not particularly limited, and examples thereof include polyoxygen chains (Japanese: polyoxysilen), polymethylene chains, polyether chains, poly Ester chains, polysiloxane chains, poly(meth)acrylate chains, polystyrene-vinyl acetate chains, polyamide chains, polyimide chains, polyurethane chains, polyurea chains, polypeptide chains, etc. Among them, compounds in which Y ¹¹ is -O-CO- and Y ¹² is -CO-O- are preferred. When the polymer chains represented by A ¹¹ and A ¹² are polyether chains and polyester chains, they are particularly cheap and easy to manufacture, so More preferred.

In the above general formula (I), A ¹¹ and A ¹² are polyether chain polymer azo compounds, the compound represented by the following general formula (II) provides good solubility, easy control of the molecular weight of the polymerization initiator and dispersibility Highly grafted pigments are therefore more preferred.

In formula (II), R ¹² , R ¹³ , R ²² , R ²³ , a and b are the same as the above general formula (I), R ¹¹ and R ²¹ independently represent an alkyl group with 1 to 24 carbon atoms, and Z ¹¹ , Z ¹² , Z ²¹ and Z ²² each independently represent an alkylene group with 1 to 4 carbon atoms, m, n, s and t are each independently a number from 0 to 1000, the sum of m+n, s+ The sums of t are each independently 2 or more.

In the above general formula (II), the alkylene groups having 1 to 4 carbon atoms represented by Z ¹¹ , Z ¹² , Z ²¹ and Z ²² include methylene, ethylene, trimethylene, propylene Base (Japanese: Propiren), Propylene (Japanese: Propiriden), Isopropylidene (Japanese: Isopropiriden), Tetramethylene, Butylene, Isobutylene, Ethylethylene, Dimethylethylene ^R11 and ^R21 represent alkyl groups with 1 to 24 carbon atoms, including: methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, isobutyl Amyl, pentyl, isopentyl, tert-amyl, hexyl, cyclohexyl, cyclohexylmethyl, cyclohexylethyl, heptyl, isoheptyl, tert-heptyl, n-octyl, isooctyl, tert-octyl , 2-ethylhexyl, n-nonyl, n-decyl, lauryl, stearyl, behenyl, etc. For the alkyl groups with 1 to 24 carbon atoms represented by R ¹¹ and R ²¹ , when the carbon number is 1 to 4, a grafted pigment with high dispersibility is provided, and one end of the chain polymer has a hydroxyl group. Since the reactivity of the esterification reaction of a compound and an azodicarboxylic acid compound is high, it is preferable.

Of the polymeric azo compounds represented by the general formula (I) above, A ¹¹ and A ¹² are polyester chain substances, compounds represented by the following formula (III) are preferable because they have good solubility and excellent water resistance.

In formula (III), R ¹² , R ¹³ , R ²² , R ²³ , a and b are the same as those in general formula (I) above, and Z ¹³ and Z ²³ each independently represent an alkylene group having 1 to 18 carbon atoms , R ³¹ and R ⁴¹ each independently represent a hydrogen atom or an alkyl group having 1 to 24 carbon atoms, and p and u each independently represent a number of 1 to 1,000.

In the above general formula (III), the alkylene group having 1 to 18 carbon atoms represented by Z ¹³ and Z ²³ includes methylene, ethylene, trimethylene, and propylene (Japanese: propilen) , Propylene (Japanese: Propiriden), Isopropylidene (Japanese: Isopropiriden), Tetramethylene, Butylene, Isobutylene, Ethylethylene, Dimethylethylene, Pentylene, Hexylene, heptylene, octylene, 1,4-pentanediyl, decylene, undecylene, 1,4-undecanediyl, dodecylene, 1,11-decylene Heptadecanediyl, octadecylene, etc., the alkyl group having 1 to 24 carbon atoms represented by R ³¹ and R ⁴¹ include the alkyl groups exemplified as R ¹¹ and R ²¹ in the above general formula (II) . For the alkyl groups with 1 to 24 carbon atoms represented by R ³¹ and R ⁴¹ , when the carbon number is 1 to 4, a grafted pigment with high dispersibility is provided, and one end of the chain polymer has a hydroxyl group Since the reactivity of the esterification reaction of a compound and an azodicarboxylic acid compound is high, it is preferable.

In the above general formula (III), when p and u are 20 to 100, the esterification reaction between a compound having a hydroxyl group at one terminal of the chain polymer and an azodicarboxylic acid compound provides a highly dispersible grafted pigment Since the reactivity is high, it is preferable.

The content of the polymeric azo initiator in the liquid crystal dropping process sealant of the present invention is not particularly limited, but with respect to 100 parts by weight of the resin having the above-mentioned (meth)acryloyl group, the preferred lower limit is 0.1 parts by weight, A preferable upper limit is 30 parts by weight. When content of the said polymeric azo initiator is less than 0.1 weight part, superposition|polymerization of the resin which has the said (meth)acryloyl group may not fully progress. When content of the said polymeric azo initiator exceeds 30 weight part, the viscosity of the sealing compound for liquid crystal dropping methods obtained may become high, and may exert a bad influence on coating workability. The more preferable lower limit of content of the said polymeric azo initiator is 0.5 weight part, and a more preferable upper limit is 10 weight part.

The sealing compound for liquid crystal dropping methods of this invention contains the resin which has a (meth)acryloyl group.

The above-mentioned resin having a (meth)acryloyl group is not particularly limited, and examples thereof include ester compounds obtained by reacting a compound having a hydroxyl group with (meth)acrylic acid, and ester compounds obtained by reacting (meth)acrylic acid with an epoxy compound. Epoxy (meth)acrylate obtained by reaction, and (meth)acrylic urethane obtained by reacting the (meth)acrylic acid derivative which has a hydroxyl group, and isocyanate.

The ester compound obtained by reacting a compound having a hydroxyl group with the above-mentioned (meth)acrylic acid is not particularly limited, and monofunctional ester compounds include, for example, 2-hydroxyethyl (meth)acrylate, (meth) 2-hydroxypropyl acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, Isooctyl (meth)acrylate, lauryl (meth)acrylate, stearate (meth)acrylate, isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, (meth)acrylic acid -2-methoxyethyl ester, methoxyethylene glycol (meth)acrylate, 2-ethoxyethyl (meth)acrylate, tetrahydrofuryl (meth)acrylate, benzyl (meth)acrylate Esters, Ethyl Carbitol (Meth) Acrylate, Phenoxy Ethyl (Meth) Acrylate, Phenoxy Diethylene Glycol (Meth) Acrylate, Phenoxy Polyethylene Glycol (Meth) Acrylates, Methoxypolyethylene glycol (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl (meth) Acrylate, 1H, 1H, 5H-octafluoropentyl (meth)acrylate, imide (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, (meth) n-butyl acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-butyl (meth)acrylate Octyl esters, isononyl (meth)acrylate, isomyristyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, Dicyclopentenyl (meth)acrylate, isodecyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, 2-(methyl) ) acryloyloxyethyl succinic acid, 2-(meth)acryloyloxyethyl hexahydrophthalic acid, 2-(meth)acryloyloxyethyl-2-hydroxypropyl phthalate, ( Glycidyl meth)acrylate, 2-(meth)acryloyloxyethyl phosphate, and the like.

In addition, bifunctional ester compounds include, for example, 1,4-butanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, (Meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol 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(meth)acrylate, Ethylene glycol di(meth)acrylate , diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene oxide addition bisphenol A di(meth) Acrylates, ethylene oxide added bisphenol A di(meth)acrylate, ethylene oxide added bisphenol F di(meth)acrylate, dimethylol dicyclopentadienyl bis(meth)acrylate base) acrylate, 1,3-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethylene oxide modified isocyanurate di(meth)acrylate, 2-Hydroxy-3-(meth)acryloxypropyl (meth)acrylate, carbonate diol di(meth)acrylate, polyether diol di(meth)acrylate, polyester diol Alcohol di(meth)acrylate, polycaprolactone diol di(meth)acrylate, polybutadiene diol di(meth)acrylate, and the like.

In addition, ester compounds having more than trifunctionality include, for example, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, propylene oxide-added trimethylolpropane tri(methyl) Acrylates, ethylene oxide added trimethylolpropane tri(meth)acrylate, caprolactone-modified trimethylolpropane tri(meth)acrylate, ethylene oxide added isocyanuric acid Tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate , glycerol tri(meth)acrylate, propylene oxide addition glycerol tri(meth)acrylate, tri(meth)acryloyloxyethyl phosphate, etc.

The epoxy (meth)acrylate obtained by reacting the above-mentioned (meth)acrylic acid with an epoxy compound is not particularly limited. Compounds obtained by reacting in the presence of a catalyst, etc.

The epoxy compound used as a raw material for synthesizing the epoxy (meth)acrylate is not particularly limited, and examples of commercially available compounds include bisphenol A such as EPICOAT828EL and EPICOAT1004 (both manufactured by Japan Epoxy Resin Co., Ltd.). Epoxy resin; bisphenol F type epoxy resin such as EPICOAT806, EPICOAT4004 (all made by Japan Epoxy Resin Company); bisphenol S type epoxy resin such as EPICLON EXA1514 (manufactured by Dainippon Ink Co.); RE-810NM (Japan 2,2'-diallyl bisphenol A type epoxy resin such as Kayaku Co., Ltd.; hydrogenated bisphenol type epoxy resin such as EPICLON EXA7015 (manufactured by Dainippon Ink Co., Ltd.); EP-4000S (manufactured by Asahi Denka Co., Ltd.) Bisphenol A type epoxy resin added with propylene oxide; Resorcinol type epoxy resin such as EX-201 (manufactured by Nagase Chemtex Co., Ltd.); Biphenyl type epoxy resin such as EPICOATYX-4000H (manufactured by Japan Epoxy Resin Co., Ltd.) Resin; sulfide epoxy resin such as YSLV-50TE (manufactured by Tohto Chemical Co., Ltd.); ether type epoxy resin such as YSLV-80DE (manufactured by Tohto Kasei Co., Ltd.); dicyclopentadiene such as EP-4088S (manufactured by Asahi Denka Co., Ltd.) Olefin-type epoxy resins; naphthalene-type epoxy resins such as EPICLON HP4032 and EPICLON EXA-4700 (both manufactured by Dainippon Ink Co., Ltd.); phenol novolac-type epoxy resins such as EPICLON N-770 (manufactured by Dainippon Ink Corporation); EPICLON N -670-EXP-S (manufactured by Dainippon Ink Co., Ltd.) and other o-cresol novolak-type epoxy resins; EPICLON HP 7200 (manufactured by Dainippon Ink Co., Ltd.) and other dicyclopentadiene novolac-type epoxy resins; NC-3000P ( Nippon Kayaku Co., Ltd.) and other biphenyl novolac epoxy resins; ESN-165S (Toto Kasei Co., Ltd.) and other naphthylphenol novolak-type epoxy resins, EPICOAT 630 (Nippon Epoxy Co., Ltd.), EPICLON 430 ( Glycidylamine type epoxy resin such as Dainippon Ink Co., Ltd.), TETRAD-X (manufactured by Mitsubishi Gas Chemical Co., Ltd.); ZX-1542 (manufactured by Tohto Kasei Co., Ltd.), EPICLON 726 (manufactured by Dainippon Ink Co., Ltd.), EPOLIGHT 80MFA (manufactured by Kyoeisha Chemical Co., Ltd.), DENACOL EX-611 (manufactured by Nagase Chemtex Co., Ltd.) and other alkyl polyol-type epoxy resins; Rubber-modified epoxy resins such as DENACOL EX-147 (manufactured by Nagase Chemtex Co., Ltd.); glycidyl ester compounds such as EPICOAT YL-7000 (manufactured by Nippon Epoxy Resin Co., Ltd.); ; Also YDC-13 12. YSLV-80XY, YSLV-90CR (both manufactured by Tohto Kasei Corporation), XAC4151 (made by Asahi Kasei Corporation), EPICOAT 1031, EPICOAT 1032 (both manufactured by Japan Epoxy Resin Corporation), EXA-7120 (made by Dainippon Ink Co., Ltd. Manufactured), TEPIC (manufactured by Nissan Chemical Co., Ltd.), etc.

The epoxy (meth)acrylate obtained by reacting the above-mentioned (meth)acrylic acid with an epoxy compound can be specifically obtained by, for example, resorcinol-type epoxy resin (EX-201, EX-201, (manufactured by Nagase Chemtex Co., Ltd.) 360 parts by weight, 2 parts by weight of p-methoxyphenol as a polymerization inhibitor, 2 parts by weight of triethylamine as a reaction catalyst, and 210 parts by weight of acrylic acid. .

In addition, examples of commercially available epoxy (meth)acrylates include: EBECRYL 3700, EBECRYL 3600, EBECRYL 3701, EBECRYL 3703, EBECRYL 3200, EBECRYL 3201, EBECRYL 3600, EBECRYL 3702, EBECRYL 3412, EBECRYL 860, EBECRYL RDX 63182, EBECRYL 6040, EBECRYL 3800 (all made by Daicel cytec), EA-1020, EA-1010, EA-5520, EA-5323, EA-CHD, EMA-1020 (all are Shin-Nakamura Chemical Industries Made by the company), epoxy ester M-600A, epoxy ester 40EM, epoxy ester 70PA, epoxy ester 200PA, epoxy ester 80MFA, epoxy ester 3002M, epoxy ester 3002A, epoxy ester 1600A, epoxy ester 3000M , Epoxy Ester 3000A, Epoxy Ester 200EA, Epoxy Ester 400EA (all made by Kyoeisha Chemical Co., Ltd.), DENACOL Acrylate DA-141, DENACOL Acrylate DA-314, DENACOL Acrylate DA-911 (all are Nagase Chemtex company), etc.

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

The isocyanate used as the raw material of the (meth)acrylic acid urethane obtained by reacting the above-mentioned (meth)acrylic acid derivative and isocyanate having a hydroxyl group is not particularly limited, for example, isophorone diisocyanate, 2 , 4-toluene diisocyanate, 2,6-toluene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diphenylmethane-4,4'-diisocyanate (MDI), hydrogenated MDI , polymerized MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate, benzylidine diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, wolfberry base diisocyanate ), triphenylmethane triisocyanate, tris(isocyanatophenyl) phosphorothioate, tetramethylxylylene diisocyanate, 1,6,10-undecane triisocyanate, etc.

In addition, the isocyanate used as the raw material of the (meth)acrylic acid urethane obtained by reacting the above-mentioned (meth)acrylic acid derivative and isocyanate having a hydroxyl group is not particularly limited, and for example, ethylene glycol, glycerine, Alcohol, sorbitol, trimethylolpropane, (poly)propylene glycol, carbonate diol, polyether diol, polyester diol, polycaprolactone diol and other polyols react with excess isocyanate Extended isocyanate compounds.

The (meth)acrylic acid derivative having a hydroxyl group used as a raw material of the above-mentioned (meth)acrylic acid urethane obtained by reacting a (meth)acrylic acid derivative having a hydroxyl group with isocyanate is not particularly limited, and examples thereof include : 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, etc. Mono(meth)acrylate, trihydroxy Mono(meth)acrylate or di(meth)acrylate of trihydric alcohols such as methyl ethane, trimethylolpropane, and glycerin, epoxy acrylate such as bisphenol A modified epoxy acrylate, etc. .

The above-mentioned (meth)acrylic acid urethane obtained by reacting a (meth)acrylic acid derivative having a hydroxyl group with an isocyanate can specifically, for example, be obtained by adding 134 parts by weight of trimethylolpropane and 0.2 parts by weight of BHT as a polymerization inhibitor. , 0.01 parts by weight of dibutyltin dilaurate and 666 parts by weight of isophorone diisocyanate as a reaction catalyst, reflux and stir at 60°C to react for 2 hours, and then add 2-hydroxyethyl acrylate 51 Parts by weight were obtained by stirring at 90° C. under reflux while feeding air, and reacting for 2 hours.

Examples of commercially available (meth)acrylic urethanes include: M-1100, M-1200, M-1210, M-1600 (all manufactured by Toagosei Co., Ltd.), EBECRYL 230, EBECRYL 270 、EBECRYL 4858、EBECRYL 8402、EBECRYL 8804、EBECRYL 8803、EBECRYL 8807、EBECRYL 9260、EBECRYL 1290、EBECRYL 5129、EBECRYL 4842、EBECRYL 210、EBECRYL 4827、EBECRYL 6700、EBECRYL 220、EBECRYL 2220(都是Daicel cytec公司制) , Artresin UN-9000H, Artresin UN-9000A, Artresin UN-7100, Artresin UN-1255, Artresin UN-330, Artresin UN-3320HB, Artresin UN-1200TPK, Artresin SH-500B (all made by Negami Industry Co., Ltd.), U -122P, U-108A, U-340P, U-4HA, U-6HA, U-324A, U-15HA, UA-5201P, UA-W2A, U-1084A, U-6LPA, U-2HA, U-2PHA , UA-4100, UA-7100, UA-4200, UA-4400, UA-340P, U-3HA, UA-7200, U-2061BA, U-10H, U-122A, U-340A, U-108, U -6H, UA-4000 (all made by Shin-Nakamura Chemical Industry Co., Ltd.), AH-600, AT-600, UA-306H, AI-600, UA-101T, UA-101I, UA-306T, UA-306I, etc.

The above-mentioned resin with (meth)acryloyl group preferably has hydrogen-bonding units such as -OH group, -NH-base, and _-NH base from the aspect of suppressing adverse effects on liquid crystals. From the aspects of ease of synthesis, etc., Epoxy (meth)acrylates are particularly preferred.

Moreover, it is preferable that the resin which has the said (meth)acryloyl group has 2-3 (meth)acryloyl groups in a molecule|numerator from the viewpoint of high reactivity.

In order to improve adhesiveness, it is preferable that the sealing compound for liquid crystal dropping methods of this invention contains resin which has epoxy.

The above-mentioned resin having an epoxy group is not particularly limited, and examples of commercially available products include bisphenol A epoxy resins such as EPICOAT 828EL and EPICOAT 1004 (both manufactured by Japan Epoxy Resin Co., Ltd.); EPICOAT 806, EPICOAT 4004 (both made by Japan Epoxy Resin Co., Ltd.) and other bisphenol F epoxy resins; EPICLON EXA1514 (made by Dainippon Ink Co., Ltd.) and other bisphenol S-type epoxy resins; RE-810NM (made by Nippon Kayaku Co., Ltd.), etc. 2, 2'-diallyl bisphenol A type epoxy resin; hydrogenated bisphenol type epoxy resin such as EPICLON EXA7015 (manufactured by Dainippon Ink Co., Ltd.); propylene oxide added bisphenol such as EP-4000S (manufactured by Asahi Denka Co., Ltd.) A-type epoxy resin; resorcinol-type epoxy resin such as EX-201 (manufactured by Nagase Chemtex Co., Ltd.); biphenyl-type epoxy resin such as EPICOAT YX-4000H (manufactured by Japan Epoxy Resin Co., Ltd.); Sulfide-type epoxy resins such as Tohkasei Co., Ltd.); ether-type epoxy resins such as YSLV-80DE (made by Tohto Kasei Co., Ltd.); dicyclopentadiene-type epoxy resins such as EP-4088S (made by Asahi Denka Co., Ltd.); EPICLON Naphthalene-type epoxy resins such as HP4032 and EPICLON EXA-4700 (both produced by Dainippon Ink Co., Ltd.); phenol novolak-type epoxy resins such as EPICLON N-770 (manufactured by Dainippon Ink Co., Ltd.); EPICLON N-670-EXP-S (Dainippon Ink Co., Ltd.) ortho-cresol novolak-type epoxy resin; EPICLON HP 7200 (Dainippon Ink Co., Ltd.) and other dicyclopentadiene novolac-type epoxy resin; NC-3000P (Nippon Kayaku Co., Ltd.) Equal biphenyl novolak type epoxy resin; ESN-165S (manufactured by Tohto Kasei Co., Ltd.), equal naphthylphenol novolak type epoxy resin, EPICOAT 630 (manufactured by Nippon Epoxy Resin Co., Ltd.), EPICLON 430 (manufactured by Dainippon Ink Co., Ltd.) , TETRAD-X (manufactured by Mitsubishi Gas Chemical Co., Ltd.); ZX-1542 (manufactured by Tohto Kasei Co., Ltd.); Alkyl polyol-type epoxy resins such as DENACOL EX-611 (manufactured by Nagase Chemtex Co., Ltd.); rubbers such as YR-450, YR-207 (manufactured by Tohto Kasei Co., Ltd.), EPOLEAD PB (manufactured by Daicel Chemical Co., Ltd.) Modified epoxy resins; glycidyl ester compounds such as DENACOL EX-147 (manufactured by Nagase Chemtex); bisphenol A episulfide resins such as EPICOAT YL-7000 (manufactured by Japan Epoxy Resin Co.); 1312, YSLV-80XY, YSLV-90CR (both manufactured by Tohto Kasei), XAC4151 (made by Asahi Kasei), EPICOAT 1031, EPICOAT 1032 (both made by Japan Epoxy Resin Corporation), EXA-7120 (made by Dainippon Ink Co.), TEPIC (made by Nissan chemical company), etc.

Moreover, the resin which has the said epoxy group may be a compound which has a (meth)acryloyl group and an epoxy group in 1 molecule, for example. As such a compound, the compound obtained by making some epoxy groups of the compound which has 2 or more epoxy groups react with (meth)acrylic acid, etc. are mentioned, for example.

A compound obtained by reacting a part of the epoxy groups of the above-mentioned compound having two or more epoxy groups with (meth)acrylic acid, for example, by making epoxy resin and (meth)acrylic acid in the presence of a basic catalyst according to a conventional method obtained by the reaction. Specifically, for example, 190 g of phenol novolac-type epoxy resin N-770 (manufactured by Dainippon Ink Co., Ltd.) was dissolved in 500 mL of toluene, and 0.1 g of triphenylphosphine was added to the solution to prepare a uniform solution, and the After stirring, 35 g of acrylic acid was dripped into the solution for 2 hours, and then refluxed and stirred for 6 hours, and then 50 mol% of epoxy groups and (meth)acrylic acid were reacted to obtain a novolak type solid modified epoxy resin by removing toluene. (50% partially acrylated at this point).

Among the compounds obtained by reacting a part of the epoxy groups of the compound having two or more epoxy groups with (meth)acrylic acid, commercially available products include, for example, EBECRYL 1561 (manufactured by Daicel Cytec).

When the sealant for liquid crystal dropping process of the present invention contains the resin having the above-mentioned epoxy group, it is preferable to blend the resin having (meth)acryloyl group and epoxy group in a ratio of 50:50 to 95:5. base) acryl-based resins and epoxy-based resins. When the ratio of (meth)acryloyl groups is 50% or less, there are many uncured epoxy resin components at the end of the thermal polymerization using the azo initiator, which may contaminate the liquid crystal. When the ratio of (meth)acryloyl group is 95 % or more, sufficient adhesive force may not be produced.

When the sealing compound for liquid crystal dropping methods of this invention contains the resin which has the said epoxy group, it is preferable to contain an epoxy thermosetting agent further. The above-mentioned epoxy thermosetting agent is not particularly limited, and examples thereof include organic acid hydrazides, imidazole derivatives, amine compounds, polyhydric phenol compounds, acid anhydrides, and the like. Among them, solid organic acid hydrazides are preferably used.

The above-mentioned solid organic acid hydrazide is not particularly limited, for example, sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, malonic acid hydrazide and other AJICURE VDH, AJICURE UDH ( Both are manufactured by Ajinomoto Precision Technology Co., Ltd.), etc.

The content of the epoxy thermosetting agent is not particularly limited, but the lower limit is preferably 1 part by weight and the upper limit is 50 parts by weight relative to 100 parts by weight of the epoxy group-containing resin. When the content of the above-mentioned epoxy thermosetting agent is less than 1 part by weight, the effect of containing the thermosetting agent is hardly obtained. When content of the said epoxy thermosetting agent exceeds 50 weight part, the viscosity of the sealing compound for liquid crystal dropping methods of this invention may become high, and applicability etc. may be impaired. The more preferable upper limit of content of the said epoxy thermosetting agent is 30 weight part.

As described above, the liquid crystal dropping method sealing agent of the present invention can not only thermally cure the above-mentioned resin having a (meth)acryloyl group but also photocure it, and if necessary, use the above-mentioned polymer azo initiator. Contains a photopolymerization initiator. The above-mentioned photopolymerization initiator is not particularly limited, and as a commercial product, for example, Irgacure 184, Irgacure 2959, Irgacure 907, Irgacure 819, Irgacure 651, Irgacure 369, Irgacure 379, Irgacure OXE01 (both Ciba Specialty Chemicals company), benzoin benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, Lucirin TPO (BASF Japan Co., Ltd.), etc.

The content of the photopolymerization initiator is not particularly limited, but the lower limit is preferably 0.1 parts by weight and the upper limit is 10 parts by weight relative to 100 parts by weight of the above-mentioned (meth)acryloyl group-containing resin. When content of the said photoinitiator is less than 0.1 weight part, it may not fully photocure the sealing compound for liquid crystal dropping methods of this invention. When content of the said photoinitiator exceeds 10 weight part, storage stability may fall.

The sealing compound for liquid crystal dropping methods of this invention may contain a light-shielding coloring agent further.

The sealing compound for liquid crystal dropping methods of this invention is colored by containing the said light-shielding coloring agent. Thereby, even when the width of the black mask becomes narrow and the sealant protrudes outward from directly below the black mask, it is possible to prevent backlight light from leaking out of the sealant and lowering the contrast.

When adding the said light-shielding coloring agent to the sealing compound for conventional liquid crystal dropping methods, light irradiation may be blocked and curability may be impaired. However, the sealing compound for liquid crystal dropping methods of this invention can be hardened reliably by heat by containing the resin which has the said (meth)acryloyl group, and a polymeric azo initiator.

In addition, "light-shielding property" in this specification means shielding 80% or more of the light of wavelength 370-800nm.

The said light-shielding coloring agent will not be specifically limited if it provides light-shielding property to the sealing compound for liquid crystal dropping methods of this invention after hardening, and there are few impurities in a liquid crystal. The above light-shielding colorant is preferably, for example, a black pigment or a plurality of pigments and/or dyes having a complementary color relationship to become black when mixed.

The above-mentioned black pigment is not particularly limited, and examples thereof include iron oxide, titanium black, aniline black, cyanine black, fullerene, carbon black, and resin-coated carbon black. The above black pigments may be used alone or in combination of two or more. Among them, titanium black and/or carbon black are preferable from the viewpoint of insulation and handleability.

The above-mentioned carbon black is not particularly limited as long as it is carbon black with little elution of impurities in liquid crystals, and known carbon blacks such as channel black, lamp black, furnace black, and pyrolytic black can be used, for example. Among them, from the viewpoint of insulation, grafted carbon black whose surface is grafted, coated carbon black whose surface is coated with an insulating inorganic substance or an insulating organic substance, and/or acid carbon whose surface is oxidized are preferred. black. Such carbon black has lower electrical conductivity than untreated carbon black, so when it is used for the sealing compound for liquid crystal dropping methods of the present invention, a highly reliable liquid crystal display element with little leakage of electric current can be obtained.

The above-mentioned titanium black is not particularly limited, and specific commercial products include 12S, 13M, 13MC, 13R-N (all of which are manufactured by Mitsubishi Materials Corporation), Teilac D (manufactured by Ako Kasei Co., Ltd.), and the like. In addition, titanium black whose surface is treated with a coupling agent, or titanium black coated with inorganic components such as silicon oxide, titanium oxide, germanium oxide, aluminum oxide, zirconium oxide, and magnesium oxide can also be used.

Various organic pigments having a complementary color relationship that turns black when mixed are not particularly limited, and examples thereof include azo-based pigments such as insoluble azo pigments and soluble azo pigments, copper phthalocyanine blue pigments, and copper phthalocyanine halides. Pigments, sulfonated copper phthalocyanine pigments, metal-free phthalocyanine pigments, phthalocyanine pigments such as different metal phthalocyanine pigments, or aminoanthraquinone pigments, indanthrene pigments, isoindolinone pigments, quinacridone pigments , Dioxazine pigments, perionone pigments, perylene pigments and other condensed polycyclic pigments, etc. Among them, copper halide phthalocyanine pigments or condensed polycyclic pigments are preferably used. These organic pigments can also be used as an auxiliary coloring component of the above-mentioned black pigment.

There are no particular limitations on the various dyes having the above-mentioned complementary color relationship that turns black when mixed, and examples thereof include cyanine dyes, phthalocyanine dyes, basic cyanine dyes, and basic cyanine dyes. Dyes, Oxonol (Japanese: オキソノール) dyes, styrene dyes, base styrene (Japanese: ベスステリル) dyes, benzopyran dyes, quinozine dyes, coumarin dyes, thiazoles dyes, indanthrene dyes, pyranthrone dyes, anthraquinone carbazole dyes, anthraquinone oxazole dyes, indigo dyes, thioindigo dyes, pyrazolone azo dyes, γ-acid azo Nitrogen dyes, H-acid azo dyes, triallylmethane dyes, oxazine dyes, etc. These dyes can also be used as auxiliary coloring components of the above-mentioned black pigments.

The particle size of the light-shielding colorant is not particularly limited, but the lower limit of the primary particles is preferably 10 nm, and the upper limit is preferably 500 nm. When the particle diameter of the said light-shielding coloring agent is outside this range, the dispersibility in the sealing compound for dropping methods of this invention will worsen.

The content of the light-shielding coloring agent is not particularly limited, but the lower limit is preferably 5 parts by weight, and the upper limit is preferably 50 parts by weight relative to 100 parts by weight of the total weight of the sealing agent for dropping methods of the present invention. When the content of the above-mentioned light-shielding coloring agent is less than 5 parts by weight, sufficient light-shielding properties may not be obtained, and when it exceeds 50 parts by weight, the adhesiveness of the sealant for liquid crystal dropping method of the present invention to the substrate or the strength after curing may be reduced. Reduced, or degraded. The more preferable minimum of content of the said light-shielding coloring agent is 10 weight part, and a more preferable upper limit is 40 weight part.

The sealing agent for dropping methods of the present invention may contain pigments (organic pigments, inorganic pigments) or dyes as auxiliary coloring components in addition to the light-shielding colorant. For example, when the black pigment is reddish black, the light-shielding colorant can be made to exhibit more desirable black by adding an auxiliary coloring component that exhibits blue as a complementary color to red.

It is more preferable that the sealing compound for liquid crystal dropping methods of this invention contains a silane coupling agent. The above-mentioned silane coupling agent mainly has a role as an adhesion auxiliary agent for adhering the sealing agent for a liquid crystal dropping process and the liquid crystal display element substrate to a good adhesion.

The above-mentioned silane coupling agent is not particularly limited. Since it has an excellent effect of improving the adhesiveness with a glass substrate and the like, and can be chemically bonded with a curable resin to prevent flow into the liquid crystal, it is preferable to use, for example, γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-isocyanatopropyltrimethoxysilane, and the like. These silane coupling agents may be used alone or in combination of two or more.

The sealant for liquid crystal dropping methods of the present invention may further contain a filler for the purpose of improving the adhesiveness due to the stress dispersion effect, improving the linear expansion coefficient, and the like.

The aforementioned fillers are not particularly limited, and examples thereof include talc, asbestos, silica, diatomaceous earth, montmorillonite, bentonite, calcium carbonate, magnesium carbonate, alumina, montmorillonite, diatomaceous earth, and zinc oxide. , iron oxide, magnesium oxide, tin oxide, titanium oxide, magnesium hydroxide, aluminum hydroxide, glass beads, silicon nitride, barium sulfate, gypsum, calcium silicate, talc, glass beads, sericite activated clay, bentonite, nitrogen Inorganic fillers such as aluminum chloride, or organic fillers such as polyester particles, polyurethane particles, vinyl polymer particles, and acrylic polymer particles.

The sealing agent for liquid crystal dropping process of the present invention may also contain a reactive diluent for viscosity adjustment, a thixotropic agent for adjusting thixotropy, spacers such as polymer beads for adjusting panel gaps, 3-pair Chlorophenyl-1,1-dimethylurea and other curing accelerators, defoamers, leveling agents, polymerization inhibitors, other additives, etc.

The method for producing the sealant for liquid crystal display elements of the present invention is not particularly limited, and examples thereof include mixing the above-mentioned resin having a (meth)acryloyl group, a polymeric azo initiator, and, if necessary, a Additives and the like are mixed.

A vertical conduction material can be manufactured by mix|blending electroconductive fine particle with the sealing compound for liquid crystal dropping methods of this invention.

The above-mentioned conductive fine particles are not particularly limited, and for example, metal balls, materials having a conductive metal layer formed on the surface of resin fine particles, and the like can be used. Among them, a material in which a conductive metal layer is formed on the surface of resin fine particles is preferable because it can realize conductive connection without damaging electrodes or the like by utilizing the excellent elasticity of resin fine particles.

The liquid crystal display element manufactured using the sealing compound for liquid crystal dropping methods of this invention and/or the vertical conduction material of this invention is also one of this invention.

The method for producing a liquid crystal display element of the present invention includes, for example, a method including a step of printing or applying the liquid crystal dropping process sealant or the like of the present invention by screen printing, dispensing coating, or the like. A process of forming a seal pattern on one side of a substrate with two electrodes such as an ITO film; a process of drip-coating tiny droplets of liquid crystal in the frame of the seal pattern, and overlapping the other substrate in a vacuum; and the process of the present invention A step of pre-curing by irradiating the sealant for liquid crystal dropping method with light such as ultraviolet rays, and a step of main curing the seal pattern composed of the sealant for liquid crystal dropping method of the present invention by heating.

The liquid crystal display element manufactured using the sealing compound for liquid crystal dropping methods of this invention mentioned above and/or the vertical conduction material of this invention is also one of this invention.

The sealing agent for liquid crystal panels containing the resin which has the said (meth)acryloyl group, and the said polymeric azo initiator is also one of this invention.

When manufacturing a liquid crystal display device using the conventional vacuum injection method, as in the case of manufacturing a liquid crystal display device using the above-mentioned liquid crystal dropping method, the liquid crystal panel sealant contacts the liquid crystal in an uncured state when sealing the liquid crystal. At this time, if sufficient light is not irradiated to the sealing agent for liquid crystal panels, color unevenness will still occur around the sealing part, and a liquid crystal display element with a high-quality image cannot be obtained. When the sealing agent for liquid crystal panels of this invention is used as a sealing agent at the time of manufacturing a liquid crystal display device by the vacuum injection method, the liquid crystal display element of a high-quality image with few color unevenness can be manufactured. In particular, it is extremely effective in the case of a panel design that does not sufficiently irradiate ultraviolet light.

The sealing agent for liquid crystal panel of the present invention is the same as the sealing agent for liquid crystal dropping process of the present invention, and may contain a resin having an epoxy group, an epoxy thermosetting agent, a photopolymerization initiator, a light-shielding colorant, a silane coupling agent, Fillers, various additives, etc.

According to this invention, when manufacturing a liquid crystal display element by a dropping process, the sealing compound for liquid crystal dropping methods which can manufacture a liquid crystal display element with few color unevenness and a high-quality image is provided. Also provided is a sealing agent for a liquid crystal panel capable of producing a high-quality image with less color unevenness when a liquid crystal display device is manufactured by a vacuum injection method.

Description of drawings

FIG. 1 is a diagram schematically showing a procedure for manufacturing a liquid crystal display element by a liquid crystal dropping method in Examples and Comparative Examples.

FIG. 2 is a diagram schematically showing a procedure for manufacturing a liquid crystal display element by a vacuum injection method in Examples and Comparative Examples.

Detailed ways

Hereinafter, although an Example is given and the form of this invention is demonstrated in more detail, this invention is not limited only to these Examples.

(Synthesis of epoxy acrylate (EX-201 modified product))

Dissolve 120g of EX-201 (resorcinol-type epoxy resin) in 500mL of toluene, and add 0.1g of triphenylphosphine to the solution to make a uniform solution. In this solution, 70 g of acrylic acid was dripped over 2 hours under reflux stirring, and then reflux stirring was carried out for 8 hours. Then, epoxy acrylate (EX-201 modified product) in which all epoxy groups were modified into acryloyl groups was obtained by removing toluene.

(Synthesis of partially acryloylated epoxy acrylate (N-770 partially modified product))

190g N-770 (phenol novolak type epoxy resin) is dissolved in 500mL toluene, in this solution, add 0.1g triphenylphosphine to make uniform solution, in this solution, drop 35g under reflux stirring with 2 hours After acrylic acid, it was stirred at reflux for another 6 hours. Then, by removing toluene, 50 mol% of epoxy group-modified into acryloyl group partially acryloylated epoxy acrylate (N-770 partially modified product) was obtained.

(Examples 1-10, and Comparative Examples 1-3)

According to the mixing ratio described in Table 1, each material was mixed with a planetary mixer ("Awatori Rentaro" manufactured by Thinky Co., Ltd.), and then mixed with a three-roller mill to prepare Examples 1 to 10 and Comparative Example. Sealant for liquid crystal dropping process of 1 to 3.

As shown in Fig. 1, the liquid crystal dropping process sealant obtained is applied with a dispenser to draw a square frame on the substrate on which the transparent electrode and alignment film are formed, and is obtained by dotting the inside of the square frame. Sealant for liquid crystal dropping process. Next, tiny droplets of liquid crystal ("JC-5004LA" manufactured by Chisso Co., Ltd.) are dropped and coated on the entire frame of the transparent base, and other substrates on which the transparent electrodes and alignment films are formed are stacked in a vacuum. After the vacuum is released, the outer frame The sealed part was irradiated with ultraviolet light at 100 mW/cm ² for 30 seconds with a high-pressure mercury lamp. At this time, a mask is formed so that UV may not be irradiated to the sealant for liquid crystal dropping process after dotting. Then, liquid crystal annealing was performed at 120° C. for 1 hour, and at the same time, the sealing compound for liquid crystal dropping methods was thermally cured to obtain a liquid crystal display element.

<Evaluation>

The following evaluation was performed about the sealing compound for liquid crystal dropping methods obtained in Examples 1-10 and Comparative Examples 1-3, and a liquid crystal display element. The results are shown in Table 1.

(evaluation of panel display unevenness)

About the obtained liquid crystal display element, the color irregularity which arises in the liquid crystal around the sealing compound for liquid crystal dropping methods after dotting was visually observed in an energized state and a non-energized state. As a result, the case with no stains at all was evaluated as "◎"; the case with almost no stains was evaluated as "○"; the case with a small amount of stains was evaluated as "△"; the case with many stains was evaluated as "×" ".

(Evaluation of Adhesive Strength)

Disperse 3 parts by weight of polymer microbeads ("Micro-Pearl SP" manufactured by Sekisui Chemical Industry Co., Ltd.) with an average particle diameter of 5 μm with respect to 100 parts by weight of the obtained sealant for liquid crystal dropping process using a planetary agitator. Make a uniform liquid, take a very small amount on the central part of Corning glass 1737 (20mm×50mm×1.1mmt), overlap the same type of glass on it, squeeze the sealant for the liquid crystal dropping process to make it diffuse, and use 100mW/cm ² Irradiate ultraviolet light for 20 seconds. Then, it heated at 120 degreeC for 1 hour, and obtained the adhesion test piece. The adhesive strength (comparison unit: N/cm ² ) was measured for this test piece with a tensiometer.

【Table 1】

(Examples 11-15, and Comparative Examples 4-5)

The sealing agents for liquid crystal panels of Examples 11 to 15 and Comparative Examples 4 to 5 were prepared by mixing each material with a planetary mixer ("Awatori Rentaro" manufactured by Thinky Corporation) according to the compounding ratio described in Table 2.

As shown in Figure 2, on the substrate on which the transparent electrodes and alignment films are formed, the sealant for the liquid crystal dropping process of Example 1 is applied with a dispenser in such a way that a part of the square frame is interrupted, and then the other formed The substrate with the transparent electrode and the alignment film is pressurized until the sealant forms a predetermined gap, and heat-treated at 120°C for 1 hour to obtain an empty cell before liquid crystal injection. Then, after making the empty cell into a vacuum state, a liquid crystal ("JC-5004LA" manufactured by Chisso Co., Ltd.) was brought into contact with a part of the square frame where a part was interrupted, and then returned to normal pressure and left for 2 hours to obtain a cell filled with liquid crystal. unit.

Next, with the sealing agent of Examples 11 to 15 and Comparative Examples 4 to 5, after sealing a part of the square frame with the sealing agent for the obtained liquid crystal panel, the sealing agent was sealed with a high-pressure mercury lamp at 100 mW/ ^cm2 was irradiated with ultraviolet light for 30 seconds. Then, liquid crystal annealing was performed at 120° C. for 1 hour, and at the same time, the sealing agent was thermally cured to obtain a liquid crystal display element. In addition, at this time, a liquid crystal display element was also obtained under the conditions of performing liquid crystal annealing at 120° C. for 1 hour without irradiating ultraviolet rays to the sealing agent.

<Evaluation>

About the liquid crystal display elements obtained in Examples 11-15 and Comparative Examples 4-5, the panel display unevenness was evaluated by the following method. The results are shown in Table 2.

(evaluation of panel display unevenness)

About the obtained liquid crystal display element, the color irregularity which arises in the liquid crystal around a sealing part was visually observed in the energized state and the non-energized state. As a result, the case with no stains at all was evaluated as "◎"; the case with almost no stains was evaluated as "○"; the case with a small amount of stains was evaluated as "△"; the case with many stains was evaluated as "×" ".

【Table 2】

(Reference example 1~5)

According to the compounding ratio described in Table 3, after mixing each material with a planetary mixer ("Awatori Rentaro" manufactured by Thinky Co., Ltd.), and then mixing it with a three-roller mill, the liquid crystal dripping powders of Reference Examples 1 to 5 were prepared. Process sealant.

<Evaluation>

About the sealing compound for liquid crystal dropping methods obtained in Reference Examples 1-5, the OD value and curability were evaluated by the following method. Furthermore, panel display unevenness was evaluated by the same method as Example.

The results are shown in Table 3.

(Measurement of optical density (OD value))

1 g of a silica spacer (manufactured by Sekisui Chemical Industry Co., Ltd., Micro-Pearl SI) with a diameter of 5 μm was added to 100 g of the obtained sealant for a liquid crystal dropping method as a spacer, and mixed and stirred.

Coat the obtained liquid crystal dropping process sealant with spacers on a glass substrate of 50 mm x 50 mm, overlap the glass substrate of the same specification on the substrate, apply a load, and crush to the diameter of the spacer to form a uniform thickness of. Next, ultraviolet light was irradiated with a metal halide lamp at 100 mW/cm ² for 30 seconds. Then, it hardened|cured at 120 degreeC for 1 hour in an oven, and obtained the measurement sample of a light-shielding sealing agent. The optical density (OD value) of the obtained sample was measured using PDA-100 manufactured by Konica Corporation.

(evaluation of curability)

A sealant for a liquid crystal dropping process was sandwiched between two polyethylene terephthalate films so that the thickness of the sealant was about 5 μm, and a sample was prepared. The sample was irradiated with ultraviolet light at 100 mW/cm ² for 30 seconds using a high-pressure mercury lamp, and then heat-treated at 120° C. for 1 hour. When the polyethylene terephthalate film was peeled off after the heat treatment, the case where no creases remained on both surfaces was evaluated as "◯", and the case where creases remained on either side was evaluated as "x".

【table 3】

Industrial availability

According to this invention, when manufacturing a liquid crystal display element by a dropping process, the sealing compound for liquid crystal dropping methods which can manufacture a liquid crystal display element with few color unevenness and high-quality images is provided. Also provided is a sealing agent for a liquid crystal panel capable of producing a high-quality image with less color unevenness when a liquid crystal display device is manufactured by a vacuum injection method.

Claims (as amended under Article 19 of the Treaty)

1. A sealing compound for liquid crystal dripping technique, characterized in that,

It contains a resin with a (meth)acryloyl group and a polymeric azo initiator with a number average molecular weight of 5,000 to 100,000.

2. The sealing compound for liquid crystal dropping process according to claim 1, characterized in that,

The polymeric azo initiator has a polydimethylsiloxane unit or a polyoxyalkylene unit.

3. The sealing agent for liquid crystal dropping process according to claim 1 or 2, characterized in that,

It also contains epoxy-based resins and epoxy thermosetting agents.

4. The sealing agent for liquid crystal dropping process according to claim 1, 2 or 3, characterized in that,

It also contains a photopolymerization initiator.

5. The sealing agent for liquid crystal dropping process according to claim 1, 2, 3 or 4, characterized in that,

Also contains opacifying colorant.

6. An up and down conduction material, characterized in that,

The sealant for liquid crystal dropping methods described in claim 1, 2, 3, 4 or 5 and conductive fine particles are contained.

7. A sealing agent for liquid crystal panels, characterized in that,

Contains a resin with a (meth)acryloyl group and a polymeric azo initiator.

8. A liquid crystal display element, characterized in that,

The sealant for liquid crystal dropping process described in claim 1, 2, 3, 4 or 5 and/or the vertical conduction material described in claim 6 were used.

9. A liquid crystal display element, characterized in that,

The sealing agent for liquid crystal panels described in claim 7 was used.

Claims (9)

1. A sealant for liquid crystal dripping technique, characterized in that, Contains a resin with a (meth)acryloyl group and a polymeric azo initiator. 2. The sealing compound for liquid crystal dropping process according to claim 1, characterized in that, The polymeric azo initiator has a polydimethylsiloxane unit or a polyoxyalkylene unit. 3. The sealing agent for liquid crystal dropping process according to claim 1 or 2, characterized in that, It also contains epoxy-based resins and epoxy thermosetting agents. 4. The sealing agent for liquid crystal dropping process according to claim 1, 2 or 3, characterized in that, It also contains a photopolymerization initiator. 5. The sealing agent for liquid crystal dropping process according to claim 1, 2, 3 or 4, characterized in that, Also contains opacifying colorant. 6. An up and down conduction material, characterized in that, The sealant for liquid crystal dropping methods described in claim 1, 2, 3, 4 or 5 and conductive fine particles are contained. 7. A sealing agent for liquid crystal panels, characterized in that, Contains a resin with a (meth)acryloyl group and a polymeric azo initiator. 8. A liquid crystal display element, characterized in that, The sealant for liquid crystal dropping process described in claim 1, 2, 3, 4 or 5 and/or the vertical conduction material described in claim 6 were used. 9. A liquid crystal display element, characterized in that, The sealing agent for liquid crystal panels described in claim 7 was used.

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