Liquid crystal sealant for liquid crystal dripping method and liquid crystal display cell using the same

Abstract

To provide a liquid crystal sealant for a liquid crystal dripping method excellent in low liquid crystal contamination and high adhesion strength, and a liquid crystal display cell sealed by a cured product of the liquid crystal sealant.SOLUTION: A liquid crystal sealant for a liquid crystal dripping method, which contains a curable compound, a photoradical polymerization initiator, and a filler. The curable compound contains (a) a compound having one or more ethylenically unsaturated groups in a molecule, and (b) a compound having one or more thiol groups in a molecule, where the number of thiol groups (α) in the curable compound is 1.4×10-3 mol / g or more and 2.5×10-3 mol / g or less, and a value (α / β) obtained by dividing the number of thiol groups (α) in the curable compound by the number of ethylenically unsaturated groups (β) in the curable compound is 0.14 or more and 0.57 or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a liquid crystal sealant for use in a liquid crystal dropping method, and a liquid crystal display cell sealed with a cured product thereof. [Background technology]

[0002] In recent years, as part of efforts to reduce the power consumption of liquid crystal display elements, development has been underway to develop liquid crystal display elements that can reduce driving power by controlling the rewrite frequency to match the speed of the displayed image when the liquid crystal is driven with voltage, and driving the liquid crystal at a lower frequency for slower images.

[0003] However, when driven at low frequencies, the effects of liquid crystal sealant components dissolved into the liquid crystal tend to become more pronounced, and even with liquid crystal sealants that had previously not caused display defects, there was the issue of display unevenness occurring.

[0004] In order to prevent the liquid crystal sealant components from eluting into the liquid crystal, it is necessary to increase the crosslink density of the curable compound components during photocuring and reduce unreacted components as much as possible. To achieve this, it is necessary to mainly use a polyfunctional resin component that has multiple ethylenically unsaturated groups in one molecule that can react during photocuring (Patent Document 1).

[0005] On the other hand, if the crosslink density of the curable compound component is increased during photo-curing, cure shrinkage increases, which results in a decrease in adhesive strength to organic films such as alignment films, which are difficult to chemically bond.In particular, in LCD devices with narrow framed non-display areas, the area where the liquid crystal sealant and alignment film come into contact becomes large, making it difficult to achieve both power savings through low-frequency drive and a narrow framed design with high design appeal. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2014 / 034684 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a liquid crystal sealant for use in a liquid crystal dropping method, which exhibits low liquid crystal contamination and high adhesive strength, and a liquid crystal display cell sealed with the cured product thereof. [Means for solving the problem]

[0008] That is, the present invention relates to the following [1] to [7]. In this application, "(Numerical value 1) to (Numerical value 2)" indicates that the upper and lower limits are included. In addition, in this specification, "(meth)acrylate" means "acrylate" and / or "methacrylate". [1] A liquid crystal sealant for a liquid crystal dropping method, comprising a curable compound, a photoradical polymerization initiator, and a filler, The curable compound includes (a) a compound having one or more ethylenically unsaturated groups in the molecule, and (b) a compound having one or more thiol groups in the molecule, The number of thiol groups (α) in the curable compound is 1.4 × 10 -3 mol / g or more 2.5×10 -3 mol / g or less, A liquid crystal sealant for a liquid crystal dropping method, wherein the value (α / β) obtained by dividing the number of thiol groups (α) in the curable compound by the number of ethylenically unsaturated groups (β) in the curable compound is 0.14 or more and 0.57 or less. [2] The number of ethylenically unsaturated groups (β) in the curable compound is 2.9 × 10 -3 mol / g or more 5.1×10 -3 mol / g or less. [3] The liquid crystal sealant for a liquid crystal dropping method according to the above item [1] or [2], wherein the amount of the filler added is 50 to 90 parts by weight based on 100 parts by weight of the curable compound. [4] The liquid crystal sealant for the liquid crystal dropping method according to any one of the above items [1] to [3], which contains, as the component (a), a polybutadiene compound having one or more ethylenically unsaturated groups in the molecule. [5] The liquid crystal sealant for a liquid crystal dropping method according to any one of the above items [1] to [4], further comprising a heat curing agent and / or a thermal radical polymerization initiator. [6] The liquid crystal sealant for a liquid crystal dripping method according to the above item [4], wherein the thermal radical polymerization initiator is a thermal radical polymerization initiator that does not contain an oxygen-oxygen bond (-OO-) or a nitrogen-nitrogen bond (-N=N-) in the molecule. [7] A liquid crystal display cell sealed with the liquid crystal sealant for the liquid crystal dropping method according to any one of the preceding items [1] to [6]. [Effects of the Invention]

[0009] The present invention can provide a liquid crystal sealant for the liquid crystal dropping method, which has low liquid crystal contamination and high adhesive strength, and a liquid crystal display cell sealed with the cured product thereof. [Brief explanation of the drawings]

[0010] [Figure 1] This is a substrate for adhesion testing used in the examples of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0011] The liquid crystal sealant for a liquid crystal dropping method of the present invention (hereinafter also simply referred to as "liquid crystal sealant") is a liquid crystal sealant for a liquid crystal dropping method containing a curable compound, a photoradical polymerization initiator, and a filler, wherein the curable compound contains (a) a compound having one or more ethylenically unsaturated groups in the molecule (hereinafter also simply referred to as "component (a)") and (b) a compound having one or more thiol groups in the molecule (hereinafter also simply referred to as "component (b)"), and the number of thiol groups (α) in the curable compound is 1.4 × 10 -3 mol / g or more 2.5×10 -3mol / g or less, and the value (α / β) obtained by dividing the number of thiol groups in the curable compound (α) by the number of ethylenically unsaturated groups in the curable compound (β) is 0.14 or more and 0.57 or less.

[0012] [Curable compound] The liquid crystal sealing material of the present invention contains a curable compound. The curable compound is not particularly limited as long as it is a compound that is cured by light, heat, or the like.

[0013] [(a) Compound having one or more ethylenically unsaturated groups in the molecule] The liquid crystal sealant of the present invention contains component (a) as a curable compound. The ethylenically unsaturated group in the present invention is a curable substituent, and examples thereof include a vinyl group, an allyl group, a propargyl group, a butenyl group, an ethynyl group, a phenylethynyl group, a maleimide group, a nadimide group, and a (meth)acryloyl group.

[0014] Component (a) is not particularly limited as long as it is a compound having one or more ethylenically unsaturated groups in the molecule, but is preferably a (meth)acrylate, an epoxy (meth)acrylate, a urethane (meth)acrylate, an epoxy resin, or a polybutadiene compound having an ethylenically unsaturated group.

[0015] [(Meth)acrylate] Specific examples of (meth)acrylates include N-acryloyloxyethylhexahydrophthalimide, acryloylmorpholine, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, cyclohexane-1,4-dimethanol mono(meth)acrylate, tetrahydrofurfuryl (meth)acrylate, phenoxyethyl (meth)acrylate, phenylpolyethoxy (meth)acrylate, 2-hydroxy-3-phenyloxypropyl (meth)acrylate, and o-phenylphenol monoethoxy. ethoxy (meth)acrylate, o-phenylphenol polyethoxy (meth)acrylate, p-cumylphenoxyethyl (meth)acrylate, isobornyl (meth)acrylate, tribromophenyloxyethyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate acrylate, tricyclodecane dimethanol (meth)acrylate, bisphenol A polyethoxydi(meth)acrylate, bisphenol A polypropoxydi(meth)acrylate, bisphenol F polyethoxydi(meth)acrylate, ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, tris(acryloxyethyl) isocyanurate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate )acrylate, tripentaerythritol hexa(meth)acrylate, tripentaerythritol penta(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolpropane polyethoxytri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, ester diacrylate of neopentyl glycol and hydroxypivalic acid, and diacrylate of an ε-caprolactone adduct of an ester of neopentyl glycol and hydroxypivalic acid.Preferred examples include o-phenylphenol monoethoxy(meth)acrylate and o-phenylphenol polyethoxy(meth)acrylate.

[0016] [Epoxy (meth)acrylate] Epoxy (meth)acrylates are obtained by a known method by reacting an epoxy resin with (meth)acrylic acid. The epoxy resin used as a raw material is not particularly limited, but is preferably a bifunctional or higher epoxy resin. Examples include dimer acid-modified epoxy resins, resorcinol diglycidyl ethers, bisphenol A epoxy resins, bisphenol F epoxy resins, bisphenol S epoxy resins, phenol novolac epoxy resins, cresol novolac epoxy resins, bisphenol A novolac epoxy resins, bisphenol F novolac epoxy resins, alicyclic epoxy resins, aliphatic linear epoxy resins, glycidyl ester epoxy resins, glycidyl amine epoxy resins, hydantoin epoxy resins, isocyanurate epoxy resins, phenol novolac epoxy resins having a triphenolmethane skeleton, and diglycidyl ethers of bifunctional phenols such as catechol and resorcinol, diglycidyl ethers of bifunctional alcohols, and their halides and hydrogenated derivatives. Among these, bisphenol A type epoxy resin and resorcinol diglycidyl ether are preferred from the viewpoint of liquid crystal contamination. The ratio of epoxy groups to (meth)acryloyl groups is not limited, and is appropriately selected from the viewpoint of process compatibility. Partial epoxy (meth)acrylates in which some of the epoxy groups are acrylic esters are preferably used, with the acrylic ester content preferably being about 30 to 70%.

[0017] [Urethane (meth)acrylate] Urethane (meth)acrylates have a flexible skeleton specific to the urethane structure, and therefore the cured product has flexibility and low moisture permeability, and can conform to the bending of flexible displays. Therefore, urethane (meth)acrylates are preferably used as curable compounds, and it is even more preferable to use those having a polyester structure. The urethane (meth)acrylate can be obtained by reacting (A) a polyol, (B) an organic polyisocyanate, and (C) a hydroxyl group-containing (meth)acrylate to synthesize it in a conventional manner, and a catalyst such as a tin compound may be used as needed. In the synthesis of urethane (meth)acrylate, 1 equivalent of hydroxyl groups of the component (A) is preferably reacted with 1.1 to 2.0 equivalents, and particularly preferably 1.3 to 2.0 equivalents, of isocyanate groups of the component (B). The reaction temperature is preferably room temperature (25°C) to 100°C. It is preferable to react 0.95 to 1.1 equivalents of hydroxyl groups in component (C) with 1 equivalent of isocyanate groups in the reaction product of component (A) and component (B). The reaction temperature is preferably room temperature (25°C) to 100°C.

[0018] Specific examples of (A) polyols include tricyclodecane dimethanol, hydrogenated polybutadiene polyol, dimer diol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,14-tetradecanediol, 1,16-hexadecanediol, 1,18-octadecanediol, 1,20-icosanediol, and 1-methyl-1,8-octanediol. Examples of the diols (A-1) include 2-methyl-1,8-octanediol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, cyclohexane-1,4-dimethanol, polyethylene glycol, polypropylene glycol, bisphenol A poly(n≒2-20)ethoxydiol, and bisphenol A poly(n≒2-20)propoxydiol, and polyester polyols (A-2) that are reaction products of these diols (A-1) with dibasic acids or their anhydrides (e.g., succinic acid, adipic acid, azelaic acid, sebacic acid, dimer acid, isophthalic acid, terephthalic acid, phthalic acid, or anhydrides thereof). Preferred are polyester polyols and polyols having an aromatic ring, and particularly preferred are polyester polyols having an aromatic ring. Examples of the aromatic ring include aromatic hydrocarbon rings such as a benzene ring, a naphthalene ring, an anthracene ring, and a phenanthroline ring; and aromatic heterocycles such as a furan ring, a pyrrole ring, a thiophene ring, a pyridine ring, a thiazole ring, and a benzothiazole ring; and preferably a benzene ring or a naphthalene ring. The component (a) may be used alone or in combination of two or more.

[0019] Specific examples of (B) organic polyisocyanate include tolylene diisocyanate, isophorone diisocyanate, 1,6-hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, xylylene diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, trimethylhexamethylene diisocyanate, dimeryl diisocyanate, 1,5-naphthalene diisocyanate, 3,3'-dimethyl-4,4'-diphenylene diisocyanate, etc. Preferred examples include tolylene diisocyanate, isophorone diisocyanate, 1,6-hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate.

[0020] Specific examples of the (C) hydroxyl group-containing (meth)acrylate include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 1,4-butanediol (meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, pentaerythritol tri(meth)acrylate, an ε-caprolactone adduct of 2-hydroxyethyl (meth)acrylate, and 2-hydroxy-3-phenyloxypropyl (meth)acrylate. Preferred examples include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and polyethylene glycol mono(meth)acrylate.

[0021] The lower limit of the weight average molecular weight of the urethane (meth)acrylate in terms of polystyrene measured by GPC is preferably 1000 or more, more preferably 2000 or more, particularly preferably 3000 or more, and most preferably 4000 or more. The upper limit is preferably 10000 or less, more preferably 8000 or less, particularly preferably 7000 or less, and most preferably 6000 or less. By being in the above range, the viscosity of the liquid crystal sealant can be in an appropriate range while maintaining good flexibility and moisture permeability.

[0022] [Polybutadiene compound having one or more ethylenically unsaturated groups in the molecule] Polybutadiene compounds having one or more ethylenically unsaturated groups in the molecule are commercially available, for example, as JP-100, JP-200, TEAI-1000, and TE-2000 manufactured by Nippon Soda Co., Ltd. From the viewpoint of reducing liquid crystal contamination, the lower limit of the number average molecular weight of these polybutadiene compounds is preferably 500, more preferably 750, and particularly preferably 1000. From the viewpoint of handleability, the upper limit of the number average molecular weight is preferably 10000, more preferably 8000, and particularly preferably 6000.

[0023] [(b) Compounds having one or more thiol groups in the molecule] The liquid crystal sealing material of the present invention contains component (b) as a curable compound. Component (b) is not particularly limited as long as it is a compound having one or more thiol groups in the molecule. Examples of the component (b) include methanedithiol, 1,2-dimercaptoethane, 1,2-dimercaptopropane, 2,2-dimercaptopropane, 1,3-dimercaptopropane, 1,2,3-trimercaptopropane, 1,4-dimercaptobutane, 1,6-dimercaptohexane, bis(2-mercaptoethyl)sulfide, 1,2-bis(2-mercaptoethylthio)ethane, 1,5-dimercapto-3-oxapentane, and 1,8-dimercapto-3,6-dioxaoctanol. mercaptomethyl-1,4-dimercaptobutane, 2,2-dimethylpropane-1,3-dithiol, 3,4-dimethoxybutane-1,2-dithiol, 2-mercaptomethyl-1,3-dimercaptopropane, 2-mercaptomethyl-1,4-dimercaptobutane, 2-(2-mercaptoethylthio)-1,3-dimercaptopropane, 1,2-bis(2-mercaptoethylthio)-3-mercaptopropane, 1,1,1-tris(mercaptomethyl)propane, tetrakis(mercaptomethyl)methane, ethylene glycol 1,4-Butanediol bis(2-mercaptoacetate), 1,4-Butanediol bis(3-mercaptopropionate), trimethylolpropane tris(2-mercaptoacetate), trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(2-mercaptoacetate), pentaerythritol tetrakis(3-mercaptopropionate) dimercaptopropionate), 1,1-dimercaptocyclohexane, 1,4-dimercaptocyclohexane, 1,3-dimercaptocyclohexane, 1,2-dimercaptocyclohexane, dipentaerythritol hexakis(3-mercaptopropionate), dipentaerythritol hexakis(2-mercaptoacetate), 1,2-dimercaptobenzene, 1,3-dimercapto-2-propanol, 2,3-dimercapto-1-propanol, 1,2-dimercapto-1,3-Butanediol, Hydroxyethyl-tris(mercaptoethylthiomethyl)methane, Hydroxyethylthiomethyl-tris(mercaptoethylthio)methane, Ethylene glycol bis(3-mercaptopropionate), Propylene glycol bis(3-mercaptopropionate), Butanediol bis(3-mercaptopropionate), Octanediol bis(3-mercaptopropionate), Tetraethylene glycol bis(3-mercaptopropionate), Ethylene glycol bis(4- mercaptobutyrate), propylene glycol bis(4-mercaptobutyrate), butanediol bis(4-mercaptobutyrate), octanediol bis(4-mercaptobutyrate), trimethylolpropane tris(4-mercaptobutyrate), pentaerythritol tetrakis(4-mercaptobutyrate), ethylene glycol bis(6-mercaptovalerate), propylene glycol bis(6-mercaptovalerate), butanediol bis(6-mercaptovalerate), octa Trimethylolpropane bis(6-mercaptovalerate), trimethylolpropane tris(6-mercaptovalerate), pentaerythritol tetrakis(6-mercaptovalerate), 1,6-hexanedithiol, 1,9-nonanedithiol, 1,10-decanedithiol, 4,4'-bis(mercaptomethyl)phenyl sulfide, 2,4'-bis(mercaptomethyl)phenyl sulfide, 2,4,4'-tri(mercaptomethyl)phenyl sulfide, 2,2',4,4'-tetra(mercaptomethyl) Examples of suitable mercaptobutyryloxy compounds include phenyl sulfide, 1,3,5-tris[2-(3-mercaptopropionyloxy)ethyl]-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 1,3,5-tris(3-mercaptobutyloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, pentaerythritol tetrakis(3-mercaptobutyrate), and 1,4-bis(3-mercaptobutyryloxy)butane, which may be used alone or in combination of two or more.

[0024] From the viewpoint of usable time at room temperature, the component (b) is preferably a secondary thiol, and further from the viewpoint of reducing contamination of the liquid crystal, a compound having two or more thiol groups in the molecule is preferred.

[0025] The component (b) may be produced by a known method, or a commercially available product may be used. An example of a commercially available product is Karenz MT manufactured by Showa Denko K.K. RTM PE1, BD1, NR1, TPMB, EHMP, MBMP, STMP, TMMP, PEMP, DPMP, TEMPIC, EGMP-4, BDMP, Multhiol Y-2, Y-3, Y-4, and PXDT manufactured by SC Organic Chemical Co., Ltd. are commercially available.

[0026] [Epoxy resin] The liquid crystal sealing material of the present invention may contain an epoxy resin as the curable compound. The epoxy resin is not particularly limited, but is preferably a bifunctional or higher functional epoxy resin, such as dimer acid-modified epoxy resin, resorcinol diglycidyl ether, bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, bisphenol A novolac epoxy resin, bisphenol F novolac epoxy resin, alicyclic epoxy resin, aliphatic linear epoxy resin, glycidyl ester epoxy resin, glycidyl amine epoxy resin, hydantoin epoxy resin, isocyanurate epoxy resin, phenol novolac epoxy resin having a triphenolmethane skeleton, and diglycidyl ethers of bifunctional phenols such as catechol and resorcinol, diglycidyl ethers of bifunctional alcohols, and their halides and hydrogenated derivatives. Of these, bisphenol A epoxy resin and resorcinol diglycidyl ether are preferred from the viewpoint of liquid crystal contamination resistance.

[0027] The curable compound of the present invention is not limited to the above materials as long as it is a compound that is cured by light, heat, etc. In addition, a plurality of types of the above materials may be mixed, and the curable compound preferably accounts for 50 to 95 mass %, more preferably 70 to 90 mass %, of the total amount of the liquid crystal sealant.

[0028] [Number of thiol groups in the curable compound (α)] The number of thiol groups (α) in the curable compound is a numerical value obtained by dividing the sum of the numbers of thiol groups in the curable compound by the total weight of the curable compound. For example, if the curable compound contains 10% by weight of a compound with a molecular weight of 100 and two thiol groups, 20% by weight of a compound with a molecular weight of 300 and three thiol groups, and 70% by weight of a curable compound with no thiol groups, the number of thiol groups (α) in the curable compound is (2 / 100) × 0.1 + (3 / 300) × 0.2 = 0.004. The molecular weight in the present invention is the number average molecular weight determined by GPC as described in the examples.

[0029] The liquid crystal sealant of the present invention has a thiol group number (α) of 1.4×10 -3 mol / g or more 2.5×10 -3 mol / g or less, and preferably 1.5×10 -3 mol / g or more 2.0×10 -3 mol / g or less is more preferable, and 1.6×10 -3 mol / g or more 2.0×10 -3 It is particularly preferable that the number of thiol groups (α) in the curable compound is 1.4 × 10 mol / g or less. -3 mol / g or more results in high adhesive strength, 2.5×10 -3 When the content is mol / g or less, the low contamination of the liquid crystal becomes favorable.

[0030] [Number of ethylenically unsaturated groups in the curable compound (β)] The number (β) of ethylenically unsaturated groups in the curable compound is a numerical value obtained by dividing the sum of the numbers of ethylenically unsaturated groups in the curable compound by the total weight of the curable compound. For example, if a curable compound contains 10% by weight of a compound having a molecular weight of 100 and two ethylenically unsaturated groups per molecule, 20% by weight of a compound having a molecular weight of 200 and one ethylenically unsaturated group per molecule, and 70% by weight of a curable compound having no ethylenically unsaturated groups, the number of ethylenically unsaturated groups (β) in the curable compound is (2 / 100) × 0.1 + (1 / 200) × 0.2 = 0.003. The molecular weight in the present invention is the number average molecular weight determined by GPC as described in the examples.

[0031] The liquid crystal sealant of the present invention has a curable compound having an ethylenically unsaturated group number (β) of 2.9×10 -3 mol / g or more 5.1×10 -3 mol / g or less, and preferably 3.1×10 -3 mol / g or more 4.6×10 -3 mol / g or less is more preferable, and 3.4×10 -3 mol / g or more 4.1×10 -3 It is particularly preferable that the number of ethylenically unsaturated groups (β) in the curable compound is 2.9×10 mol / g or less. -3 mol / g or more, it is possible to suppress the elution of the liquid crystal sealant into the liquid crystal, and -3 A high adhesive strength is achieved by keeping the value below mol / g.

[0032] [The value (α / β) obtained by dividing the number of thiol groups (α) in the curable compound by the number of ethylenically unsaturated groups (β) in the curable compound] The value (α / β) obtained by dividing the number of thiol groups (α) in the curable compound by the number of ethylenically unsaturated groups (β) in the curable compound is, for example, 0.004 / 0.003=1.33 when the number of thiol groups (α) in the curable compound is 0.004 and the number of ethylenically unsaturated groups (β) in the curable compound is 0.003.

[0033] In the liquid crystal sealant of the present invention, the value (α / β) obtained by dividing the number of thiol groups (α) in the curable compound by the number of ethylenically unsaturated groups (β) in the curable compound is preferably 0.14 to 0.57, more preferably 0.19 to 0.51, and particularly preferably 0.24 to 0.47. When (α / β) is 0.14 or more, high adhesive strength is achieved, and when it is 0.57 or less, low liquid crystal contamination is favorable.

[0034] [Photoradical polymerization initiator] The liquid crystal sealing material of the present invention preferably contains a photoradical polymerization initiator. The photoradical polymerization initiator is not particularly limited as long as it is a compound that generates radicals or acids and initiates a chain polymerization reaction when irradiated with ultraviolet light or visible light. Examples of the photoradical polymerization initiator include benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, diethylthioxanthone, benzophenone, 2-ethylanthraquinone, 2-hydroxy-2-methylpropiophenone, 2-methyl-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, camphorquinone, 9-fluorenone, and diphenyl disulfide. Specifically, IRGACURE RTM 651, 184, 2959, 127, 907, 369, 379EG, 819, 784, 754, 500, OXE01, OXE02, OXE03, OXE04, DAROCURE RTM 1173, LUCIRIN RTM TPO (both manufactured by BASF), Seikuol RTM Z, BZ, BEE, BIP, BBI (all manufactured by Seiko Chemical Co., Ltd.), Kayacure DETX-S (manufactured by Nippon Kayaku Co., Ltd.), etc. Among these, preferred is IRGACURE, an oxime ester initiator. RTM OXE01, OXE02, OXE03, OXE04, and the thioxanthone initiator Kayacure DETX-S. Furthermore, the combined use of an oxime ester initiator and a thioxanthone initiator is preferred because it allows both instant curing and curing in light-shielded areas and also allows curing under visible light. When a photoradical polymerization initiator is used in the liquid crystal sealing material of the present invention, the content thereof is usually 0.001 to 3 mass %, preferably 0.005 to 2 mass %, based on the total amount of the liquid crystal sealing material.

[0035] [Filler] The liquid crystal sealing material of the present invention preferably contains a filler. Either an organic filler or an inorganic filler can be used as the filler. The amount of the filler added is preferably 50 to 90 parts by weight relative to 100 parts by weight of the curable compound, and more preferably 50 to 90 parts by weight of the inorganic filler added relative to 100 parts by weight of the curable compound.

[0036] [Organic filler] Examples of organic fillers include urethane polymer particles, acrylic polymer particles, styrene polymer particles, styrene-olefin copolymer particles, and silicone particles. Examples of silicone particles include KMP-594, KMP-597, and KMP-598 (manufactured by Shin-Etsu Chemical Co., Ltd.), Trefil RTM E-5500, 9701, and EP-2001 (manufactured by Toray Dow Corning Co., Ltd.) are preferred, JB-800T and HB-800BK (manufactured by Negami Chemical Industrial Co., Ltd.) are preferred as urethane polymer fine particles, and Rabalon is preferred as styrene polymer fine particles. RTM T320C, T331C, SJ4400, SJ5400, SJ6400, SJ4300C, SJ5300C, and SJ6300C (manufactured by Mitsubishi Chemical) are preferred, and Septon is a styrene-olefin copolymer fine particle. RTM SEPS2004 and SEPS2063 are preferred. These organic fillers may be used alone or in combination of two or more. Two or more may be used to form a core-shell structure. Among these, acrylic polymer fine particles and silicone fine particles are preferred. When the acrylic polymer microparticles are used, it is preferable that they are acrylic rubbers with a core-shell structure consisting of two types of acrylic rubber, and it is particularly preferable that the core layer is made of n-butyl acrylate and the shell layer is made of methyl methacrylate. RTM It is sold by Aica Kogyo Co., Ltd. as F-351. Examples of the silicone microparticles include organopolysiloxane crosslinked powder and linear dimethylpolysiloxane crosslinked powder. Examples of the composite silicone rubber include the silicone rubber whose surface is coated with a silicone resin (e.g., polyorganosilsesquioxane resin). Among these microparticles, particularly preferred are silicone rubber powder of linear dimethylpolysiloxane crosslinked powder or composite silicone rubber microparticles of silicone resin-coated linear dimethylpolysiloxane crosslinked powder. These may be used alone or in combination of two or more. Preferably, the rubber powder has a spherical shape, which minimizes the increase in viscosity after addition.

[0037] [Inorganic filler] Examples of inorganic fillers include silica, silicon carbide, silicon nitride, boron nitride, calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate, mica, talc, clay, alumina, magnesium oxide, zirconium oxide, aluminum hydroxide, magnesium hydroxide, calcium silicate, aluminum silicate, lithium aluminum silicate, zirconium silicate, barium titanate, glass fiber, carbon fiber, molybdenum disulfide, and asbestos, and preferred are fused silica, crystalline silica, silicon nitride, boron nitride, calcium carbonate, barium sulfate, calcium sulfate, mica, talc, clay, alumina, aluminum hydroxide, calcium silicate, and aluminum silicate, with silica, alumina, and talc being preferred. Two or more of these inorganic fillers may be mixed and used.

[0038] [Thermal hardener] The liquid crystal sealing material of the present invention can be added with a heat curing agent to improve the reactivity. Examples of heat curing agents include, but are not limited to, compounds having a carboxy group bonded to an aromatic ring in the molecule, polyamines, polyphenols, and organic acid hydrazides. Examples of the heat curing agent include aromatic hydrazides such as terephthalic acid dihydrazide, isophthalic acid dihydrazide, 2,6-naphthoic acid dihydrazide, 2,6-pyridine dihydrazide, 1,2,4-benzenetrihydrazide, 1,4,5,8-naphthoic acid tetrahydrazide, and pyromellitic acid tetrahydrazide. Furthermore, examples of aliphatic hydrazides include formhydrazide, acetohydrazide, propionic acid hydrazide, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, pimelic acid dihydrazide, sebacic acid dihydrazide, 1,4-cyclohexane dihydrazide, tartaric acid dihydrazide, malic acid dihydrazide, iminodiacetic acid dihydrazide, N,N'-hexamethylenebissemicarbazide, citric acid trihydrazide, nitriloacetic acid trihydrazide, cyclohexanetricarboxylic acid trihydrazide, and 1,3 Examples of the dihydrazide include dihydrazides having a hydantoin skeleton such as -bis(hydrazinocarbonoethyl)-5-isopropylhydantoin, preferably a valine hydantoin skeleton (a skeleton in which the carbon atoms of the hydantoin ring are substituted with isopropyl groups), tris(1-hydrazinocarbonylmethyl)isocyanurate, tris(2-hydrazinocarbonylethyl)isocyanurate, tris(1-hydrazinocarbonylethyl)isocyanurate, tris(3-hydrazinocarbonylpropyl)isocyanurate, and bis(2-hydrazinocarbonylethyl)isocyanurate. In view of the balance between curing reactivity and latency, preferred are isophthalic acid dihydrazide, malonic acid dihydrazide, adipic acid dihydrazide, tris(1-hydrazinocarbonylmethyl)isocyanurate, tris(1-hydrazinocarbonylethyl)isocyanurate, tris(2-hydrazinocarbonylethyl)isocyanurate, and tris(3-hydrazinocarbonylpropyl)isocyanurate, and particularly preferred is tris(2-hydrazinocarbonylethyl)isocyanurate. The heat curing agent may be used alone or in combination of two or more. When a heat curing agent is used in the liquid crystal sealant of the present invention, the content thereof is preferably 0.1 to 10 mass %, more preferably 0.1 to 5 mass %, of the total amount of the liquid crystal sealant.

[0039] [Thermal radical polymerization initiator] The liquid crystal sealing material of the present invention contains a thermal radical polymerization initiator, which can improve the curing rate and curability. The thermal radical polymerization initiator is not particularly limited as long as it is a compound that generates radicals by heating and initiates a chain polymerization reaction, and examples thereof include organic peroxides, azo compounds, benzoin compounds, benzoin ether compounds, acetophenone compounds, and benzopinacol, with benzopinacol being preferred. For example, an organic peroxide is Kayamec RTM A, M, R, L, LH, SP-30C, Perkadox CH-50L, BC-FF, Kadox B-40ES, Perkadox 14, Trigonox RTM 22-70E, 23-C70, 121, 121-50E, 121-LS50E, 21-LS50E, 42, 42LS, Kayaester RTM P-70, TMPO-70, CND-C70, OO-50E, AN, Kayabutyl RTM B, Percadox 16, Kayacarvone RTM BIC-75, AIC-75 (manufactured by Kayaku Akzo Co., Ltd.), Permec RTM N, H, S, F, D, G, Perhexa RTM H,HC,TMH,C,V,22,MC,Percure RTM AH, AL, HB, Perbutyl RTM H, C, ND, L, Park Mill RTM H., D., Parloyle RTM IB, IPP, Perocta RTM ND (manufactured by NOF Corporation) and other products are available commercially.

[0040] Furthermore, commercially available azo compounds include VA-044, 086, V-070, VPE-0201, and VSP-1001 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

[0041] Preferred thermal radical polymerization initiators are those that do not have an oxygen-oxygen bond (-OO-) or a nitrogen-nitrogen bond (-N=N-) in the molecule. Thermal radical polymerization initiators that have an oxygen-oxygen bond (-OO-) or a nitrogen-nitrogen bond (-N=N-) in the molecule emit large amounts of oxygen and nitrogen when radicals are generated, which can lead to curing with air bubbles remaining in the liquid crystal sealant, resulting in reduced adhesive strength, reduced moisture permeability, and reduced properties in humid and hot environments. Benzopinacol-based thermal radical polymerization initiators (including chemically modified benzopinacol) are particularly suitable. Specifically, benzopinacol, 1,2-dimethoxy-1,1,2,2-tetraphenylethane, 1,2-diethoxy-1,1,2,2-tetraphenylethane, 1,2-diphenoxy-1,1,2,2-tetraphenylethane, 1,2-dimethoxy-1,1,2,2-tetra(4-methylphenyl)ethane, 1,2-diphenoxy-1,1,2,2-tetra(4-methoxyphenyl)ethane, 1,2 -Bis(trimethylsiloxy)-1,1,2,2-tetraphenylethane, 1,2-bis(triethylsiloxy)-1,1,2,2-tetraphenylethane, 1,2-bis(t-butyldimethylsiloxy)-1,1,2,2-tetraphenylethane, 1-hydroxy-2-trimethylsiloxy-1,1,2,2-tetraphenylethane, 1-hydroxy-2-triethylsiloxy-1,1,2,2-tetraphenylethane Examples thereof include 1-hydroxy-2-trimethylsiloxy-1,1,2,2-tetraphenylethane, 1-hydroxy-2-triethylsiloxy-1,1,2,2-tetraphenylethane, 1-hydroxy-2-t-butyldimethylsiloxy-1,1,2,2-tetraphenylethane, and 1,2-bis(trimethylsiloxy)-1,1,2,2-tetraphenylethane, preferably 1-hydroxy-2-trimethylsiloxy-1,1,2,2-tetraphenylethane, and 1,2-bis(trimethylsiloxy)-1,1,2,2-tetraphenylethane, more preferably 1-hydroxy-2-trimethylsiloxy-1,1,2,2-tetraphenylethane and 1,2-bis(trimethylsiloxy)-1,1,2,2-tetraphenylethane, and particularly preferably 1,2-bis(trimethylsiloxy)-1,1,2,2-tetraphenylethane. The benzopinacol mentioned above is commercially available from Tokyo Chemical Industry Co., Ltd., Fujifilm Wako Pure Chemical Industries, Ltd., and other companies. The hydroxy group of benzopinacol can be easily etherified by well-known methods. The hydroxy group of benzopinacol can be silyl-etherified by heating the corresponding benzopinacol with various silylating agents in the presence of a basic catalyst such as pyridine. Examples of silylating agents include commonly known trimethylsilylating agents such as trimethylchlorosilane (TMCS), hexamethyldisilazane (HMDS), and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), as well as triethylsilylating agents such as triethylchlorosilane (TECS), and t-butyldimethylsilylating agents such as t-butylmethylsilane (TBMS). These reagents are readily available commercially from silicon derivative manufacturers and other sources. The reaction amount of the silylating agent is preferably 1.0 to 5.0 moles per mole of the hydroxy group of the target compound, and more preferably 1.5 to 3.0 moles. If the molar ratio is less than 1.0, the reaction efficiency will be poor and the reaction time will be longer, which will promote thermal decomposition. If the molar ratio is more than 5.0, separation will be poor during recovery and purification will be difficult.

[0042] The content of the thermal radical polymerization initiator is preferably 0.0001 to 5 mass %, more preferably 0.0005 to 3 mass %, and particularly preferably 0.001 to 1 mass %, of the total amount of the liquid crystal sealing material of the present invention.

[0043] The liquid crystal sealing material of the present invention may further contain additives such as a curing accelerator, a silane coupling agent, a radical polymerization inhibitor, a pigment, a leveling agent, an antifoaming agent, and a solvent, if necessary.

[0044] [Curing accelerator] The reactivity of the liquid crystal sealing material of the present invention can be further improved by adding a curing accelerator, such as an organic acid or imidazole. Examples of the organic acid include organic carboxylic acids and organic phosphoric acids, with organic carboxylic acids being preferred. Specific examples include aromatic carboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, benzophenonetetracarboxylic acid, and furandicarboxylic acid, succinic acid, adipic acid, dodecanedioic acid, sebacic acid, thiodipropionic acid, cyclohexanedicarboxylic acid, tris(carboxymethyl)isocyanurate, tris(2-carboxyethyl)isocyanurate, tris(2-carboxypropyl)isocyanurate, and bis(2-carboxyethyl)isocyanurate. Furthermore, examples of the imidazole compound include 2-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 2,4-diamino-6(2'-methylimidazole(1'))ethyl-s-triazine, 2,4-diamino-6(2'-undecylimidazole(1'))ethyl-s-triazine, and 2,4-diamino-6(2'-undecylimidazole(1')). '))ethyl-s-triazine, 2,4-diamino-6(2'-ethyl-4-methylimidazole(1'))ethyl-s-triazine, 2,4-diamino-6(2'-methylimidazole(1'))ethyl-s-triazine·isocyanuric acid adduct, 2-methylimidazole isocyanuric acid 2:3 adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-3,5-dihydroxymethylimidazole, 2-phenyl-4-hydroxymethyl-5-methylimidazole, 1-cyanoethyl-2-phenyl-3,5-dicyanoethoxymethylimidazole, and the like. When a curing accelerator is used in the liquid crystal sealing material of the present invention, the amount thereof is preferably 0.1 to 10 mass %, more preferably 1 to 5 mass %, of the total amount of the liquid crystal sealing material.

[0045] [Silane coupling agents] Examples of the silane coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-(2-aminoethyl)3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)3-aminopropylmethyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, vinyltrimethoxysilane, N-(2-(vinylbenzylamino)ethyl)3-aminopropyltrimethoxysilane hydrochloride, 3-methacryloxypropyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, and 3-chloropropyltrimethoxysilane. These silane coupling agents are sold by Shin-Etsu Chemical Co., Ltd. and other companies under the names KBM series and KBE series, and are therefore readily available on the market. When a silane coupling agent is used in the liquid crystal sealant of the present invention, the amount thereof is preferably 0.05 to 3 mass % based on the total amount of the liquid crystal sealant.

[0046] [Radical polymerization inhibitor] The radical polymerization inhibitor is not particularly limited as long as it is a compound that reacts with radicals generated from a photoradical polymerization initiator, a thermal radical polymerization initiator, or the like to prevent polymerization, and can be a quinone-based, piperidine-based, hindered phenol-based, nitroso-based, etc. Specific examples include naphthoquinone, 2-hydroxynaphthoquinone, 2-methylnaphthoquinone, 2-methoxynaphthoquinone, 2,2,6,6-tetramethylpiperidine-1-oxyl, 2,2,6,6-tetramethyl-4-hydroxypiperidine-1-oxyl, 2,2,6,6-tetramethyl-4-methoxypiperidine-1-oxyl, 2,2,6,6-tetramethyl-4-phenoxypiperidine-1-oxyl, and hydroquinone. , 2-methylhydroquinone, 2-methoxyhydroquinone, parabenzoquinone, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, 2,6-di-t-butylcresol, stearyl β-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 2,2'-methylenebis(4-ethyl-6-t-butylphenol), 4,4'-thiobis(3-methyl-6-t-butylphenol) 4,4'-butylidenebis(3-methyl-6-t-butylphenol), 3,9-bis[1,1-dimethyl-2-[β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]-2,4,8,10-tetraoxaspiro[5,5]undecane, tetrakis-[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenylpropionate)methane], 1,3,5-trimethyl- Examples of suitable antibacterial agents include, but are not limited to, this(3',5'-di-t-butyl-4'-hydroxybenzyl)-sec-triazine-2,4,6-(1H,3H,5H)trione, paramethoxyphenol, 4-methoxy-1-naphthol, thiodiphenylamine, aluminum salt of N-nitrosophenylhydroxyamine, and Adeka STAB LA-81 (trade name) and Adeka STAB LA-82 (trade name) (manufactured by Adeka Corporation).Among these, naphthoquinone-, hydroquinone-, nitroso-, and piperazine-based radical polymerization inhibitors are preferred, and naphthoquinone, 2-hydroxynaphthoquinone, hydroquinone, 2,6-di-tert-butyl-p-cresol, and 2,2,6,6-tetramethylpiperidine-1-oxyl are more preferred. 2,2,6,6-tetramethylpiperidine-1-oxyl is commercially available as Polystop 7300P (manufactured by Hakuto Co., Ltd.). The content of the radical polymerization inhibitor is preferably 0.0001 to 1 mass %, more preferably 0.001 to 0.5 mass %, and particularly preferably 0.005 to 0.2 mass %, based on the total amount of the liquid crystal sealing material of the present invention.

[0047] An example of a method for obtaining the liquid crystal sealant of the present invention is the following method: First, the curable compound, photoradical initiator, thermal radical initiator, and radical polymerization inhibitor are heated and dissolved at 90°C, and then cooled to room temperature, and a silane coupling agent, curing agent, curing accelerator, filler, antifoaming agent, leveling agent, solvent, etc. are added, and the mixture is uniformly mixed using a known mixing device such as a three-roll mill, sand mill, or ball mill, and filtered through a metal mesh, thereby producing the liquid crystal sealant of the present invention.

[0048] A liquid crystal display cell manufactured using the liquid crystal sealant of the present invention comprises a pair of substrates, each having a predetermined electrode formed thereon, arranged opposite each other at a predetermined distance, the periphery of which is sealed with the liquid crystal sealant of the present invention, and a liquid crystal sealed in the gap. The type of liquid crystal to be sealed is not particularly limited. Here, the substrates are a combination of substrates made of glass, quartz, plastic, silicon, or the like, at least one of which is optically transparent. The manufacturing method involves adding a spacer (gap control material) such as glass fiber to the liquid crystal sealant of the present invention, applying the liquid crystal sealant to one of the pair of substrates using a dispenser or screen printing device, and then temporarily curing at 80 to 120°C, if necessary. Liquid crystal is then dropped inside the weir of the liquid crystal sealant, and the other glass substrate is placed on top of it in a vacuum to form a gap. After gap formation, the liquid crystal display cell of the present invention can be obtained by curing at 90 to 130°C for 30 minutes to 2 hours. When used as a combined photothermal and photothermal type, the liquid crystal sealant is photocured by irradiating it with ultraviolet light using an ultraviolet irradiator. The ultraviolet irradiation dose is preferably 500 to 6000 mJ / cm 2 , more preferably 1000 to 4000 mJ / cm 2 The preferred irradiation dose is 365 nm (measurement wavelength). Thereafter, if necessary, curing is performed at 90 to 130°C for 30 minutes to 2 hours to obtain the liquid crystal display cell of the present invention. The liquid crystal display cell of the present invention obtained in this manner is free from display defects due to liquid crystal contamination and has excellent adhesiveness and moisture-resistant reliability. Examples of spacers include glass fiber, silica beads, and polymer beads. Their diameter varies depending on the purpose, but is usually 2 to 8 μm, preferably 4 to 7 μm. The amount used is usually 0.1 to 4 parts by mass, preferably 0.5 to 2 parts by mass, and more preferably about 0.9 to 1.5 parts by mass, per 100 parts by mass of the liquid crystal sealant of the present invention. [Example]

[0049] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "parts" and "%" in the text are based on mass.

[0050] [Synthesis Example 1] A flask equipped with a thermometer, condenser, and stirrer was charged with 776.99 g of a polyester polyol (P-2012, manufactured by Kuraray Co., Ltd., hydroxyl value 54.6 mg KOH / g) of methylpentanediol, adipic acid, and isophthalic acid, and 131.68 g of toluene diisocyanate (Coronate T-100, manufactured by Tosoh Corporation, molecular weight 174.2) and reacted at 80 °C. The isocyanate content was determined by back titration with hydrochloric acid after adding excess amine. The value was confirmed to be within ±2% of the residual isocyanate content calculated from the calculated value. Next, 0.6 g of methoquinone (polymerization inhibitor), 90.43 g of 2-hydroxyethyl acrylate (molecular weight 116.1), and 0.3 g of dibutyltin dilaurate (catalyst) were added, and the mixture was stirred at 80 °C. The isocyanate group absorption spectrum (at 2280 cm) was measured by infrared absorption spectroscopy. -1 The reaction was continued until the methyl group disappeared, yielding a urethane acrylate oligomer having a weight-average molecular weight of 6,300.

[0051] [Synthesis Example 2] 100 parts (0.28 mol) of commercially available benzopinacol (Tokyo Chemical Industry Co., Ltd.) was dissolved in 350 parts of dimethylformamide. 32 parts (0.4 mol) of pyridine as a basic catalyst and 150 parts (0.58 mol) of BSTFA (Shin-Etsu Chemical Co., Ltd.) as a silylating agent were added, and the mixture was heated to 70°C and stirred for 2 hours. The resulting reaction solution was cooled and, while stirring, 200 parts of water was added to precipitate the product and deactivate the unreacted silylating agent. The precipitated product was separated by filtration and thoroughly washed with water. The resulting product was then dissolved in acetone, recrystallized with water, and purified. 105.6 parts of the desired 1,2-bis(trimethylsiloxy)-1,1,2,2-tetraphenylethane were obtained (yield 88.3%).

[0052] [Examples 1 to 20, Comparative Examples 1 to 10] The curable compound, photoradical polymerization initiator, thermal radical polymerization initiator, and radical polymerization inhibitor were heated and dissolved at 90°C in the proportions shown in Tables 1 to 3 below, and then cooled to room temperature. A silane coupling agent, a curing agent, a curing accelerator, and a filler were added and stirred, and then dispersed using a three-roll mill and filtered through a metal mesh (635 mesh) to prepare a liquid crystal sealant.

[0053] [GPC measurement] Device name: Tosoh Corporation HLC-8320GPC (TOSOH) Guard column: TSKgel guard column SuperMP(HZ)-M manufactured by Tosoh Corporation Analytical column: Tosoh Corporation TSKgel SuperMultiporeHZ-M x 3 Eluent: THF, 0.35ml / min, 40℃ Detector: RI (differential refractometer) Molecular weight calculation: Standard polystyrene equivalent Sample concentration: 50x dilution with THF Injection volume: 5μL

[0054] [VHR, LCD contamination] A 0.5 mm thick glass substrate with 10 mm wide and 20 mm long ITO transparent electrodes arranged at 2 mm intervals was spin-coated with a photo-alignment film solution (Nissan Chemical Co., Ltd.: NRB-U978L), pre-baked on a hot plate at 80°C for 2 minutes, and baked in an oven at 230°C for 30 minutes. The resulting film was then irradiated with a UV irradiator equipped with a polarizing filter at 250 mJ / cm. 2An alignment treatment was performed by irradiating ultraviolet light (measurement wavelength: 254 nm) and then baking in an oven at 230°C for 30 minutes to obtain a photo-alignment film substrate with an ITO electrode pattern. The liquid crystal sealant prepared in the examples and comparative examples contained 1% by weight of 4 μm glass fiber as a spacer, and was mixed and stirred using a planetary stirrer (VMX-360, manufactured by EME). The liquid crystal sealant, prepared by surrounding each 1 cm edge of the ITO portion on the prepared photo-alignment film substrate with an ITO electrode pattern, was applied to a 10 mm square cell with an R of 0.5 mm and a seal width of 0.6 mm. Liquid crystal (JC-7025xx, manufactured by JNC Corporation) was dropped into the center of the cell in an amount sufficient to fill the gap 100% by volume after lamination. Another photo-alignment film substrate with an ITO electrode pattern was then laminated in a vacuum of 1 to 10 Pa so that the ITO was in contact with the liquid crystal and offset by 1 mm in the longitudinal direction of the electrode. After exposure to the atmosphere, 3000 mJ / cm was applied using a UV irradiator. 2 After irradiating the cell with ultraviolet light (measurement wavelength: 405 nm), the liquid crystal sealant was cured by heating and curing in a 130°C fan oven for 40 minutes, and then the glass substrate was cut so that the electrode area was exposed, to prepare a VHR measurement cell. The VHR of the prepared VHR measurement cell was measured (initial VHR) using a VHR measurement device (Toyo Corporation: 6254C) at 60°C, 5V, 1Hz. The cell was then placed in a high-temperature, high-humidity chamber set at 60°C, 90% RH for 96 hours, after which it was removed and VHR was measured within 1 hour under the same measurement conditions as the initial VHR (VHR after 96 hours at 60°C, 90% RH).

[0055] [Adhesive strength] A photo-alignment film solution (NRB-U978L manufactured by Nissan Chemical Co., Ltd.) was spin-coated onto a 0.5 mm thick glass substrate, pre-baked on a hot plate at 80°C for 2 minutes, and then baked in an oven at 230°C for 30 minutes. The resulting film was then irradiated with a UV irradiator equipped with a polarizing filter at 250 mJ / cm. 2An alignment treatment was carried out by irradiating ultraviolet light (measurement wavelength: 254 nm) and then baking in an oven at 230°C for 30 minutes to obtain a photo-alignment film substrate. In the examples and comparative examples, 1% by weight of 4 μm glass fiber was added as a spacer to the liquid crystal sealant, and the mixture was stirred using a planetary stirrer (EME: VMX-360). The prepared liquid crystal sealant was applied to the prepared photo-alignment film substrate so as to achieve a seal width of 0.6 mm, reproducing a corner portion with R = 0.5 mm and a length of 1 cm x 1 cm. The substrate was then bonded to an opposing photo-alignment film substrate in a vacuum of 1 to 10 Pa, and after being exposed to the atmosphere, 3000 mJ / cm was applied using a UV irradiator. 2 After irradiating with ultraviolet light (measurement wavelength: 405 nm), the bond was achieved by heating and curing for 40 minutes in a 130°C fan oven. The resulting bonded substrate was cut into a shape that simulated the terminal portion of the display, with only the lower substrate protruding, as shown in Figure 1. A universal testing machine (Shimadzu Corporation: Autograph AG-Xplus500N) equipped with 3 mm diameter needle terminals was used to press the lower substrate at a point 4 mm diagonally away from the corner of the applied display sealant, and the maximum load when the bonded substrates peeled off was measured to determine the adhesive strength. A similar test was also performed on a glass substrate that had not been coated with photo-alignment liquid.

[0056] [Table 1]

[0057] [Table 2]

[0058] [Table 3]

[0059] TIFF0007824194000004.tif113153

[0060] From the results of Tables 1 to 3, it was confirmed that the liquid crystal sealant of the present invention has good low liquid crystal contamination properties not only initially but also after the humidity resistance test. It was also confirmed that it has high adhesive strength to both the glass substrate and the photo-alignment film substrate. [Industrial Applicability]

[0061] The liquid crystal sealant of the present invention is useful as a liquid crystal sealant for liquid crystal displays, particularly for liquid crystal displays that are compatible with a power-saving mode driven at a low frequency and liquid crystal displays with narrow frames and high designability.

Claims

1. A liquid crystal sealant for a liquid crystal dropping method, comprising a curable compound, a photoradical polymerization initiator, and a filler, The curable compound includes (a) a compound having one or more ethylenically unsaturated groups in the molecule, and (b) a compound having one or more thiol groups in the molecule, The component (a) contains a polybutadiene compound having one or more ethylenically unsaturated groups in the molecule, The number of thiol groups (α) in the curable compound is 1.4 × 10 －３ mol / g or more 2.5×10 －３ mol / g or less, a value (α / β) obtained by dividing the number of thiol groups (α) in the curable compound by the number of ethylenically unsaturated groups (β) in the curable compound is 0.14 or more and 0.57 or less.

2. The number of ethylenically unsaturated groups (β) in the curable compound is 2.9 × 10 －３ mol / g or more 5.1×10 －３ 2. The liquid crystal sealant for a liquid crystal dropping method according to claim 1, wherein the viscosity is 1000 s, ...

3. 2. The liquid crystal sealant for a liquid crystal dropping method according to claim 1, wherein the amount of the filler added is 50 to 90 parts by weight based on 100 parts by weight of the curable compound.

4. The liquid crystal sealant for use in a liquid crystal dropping method according to claim 1, further comprising a heat curing agent and / or a thermal radical polymerization initiator.

5. 5. The liquid crystal sealant for a liquid crystal dropping method according to claim 4, wherein the thermal radical polymerization initiator is a thermal radical polymerization initiator that does not contain an oxygen-oxygen bond (—O—O—) or a nitrogen-nitrogen bond (—N═N—) in the molecule.

6. A liquid crystal display cell sealed with the liquid crystal sealant for a liquid crystal dropping method according to claim 1 .

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