Method for manufacturing liquid crystal sealant for liquid crystal dropping construction method, and method for manufacturing liquid crystal display panel

Abstract

To provide a manufacturing method of mixing only part of a component of liquid crystal sealant with three rolls, and thereby reducing the time to manufacture liquid crystal sealant for a liquid crystal dropping construction method, and achieving improvement of productivity.SOLUTION: A method for manufacturing liquid crystal sealant for a liquid crystal dropping construction method includes the steps of: mixing a curable compound, filler, and a latent thermal curing agent to obtain a composition (X), wherein in the total amount of the curable compound, the filler, and the latent thermal curing agent, the total content of the filler and the latent thermal curing agent is 30 weight% or more and 55 weight% or less; obtaining a composition (Y) containing the curable compound; and mixing the composition (X) and the composition (Y) at a device temperature of 35-45°C to obtain the liquid crystal sealant for a liquid crystal dropping construction method.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a liquid crystal sealant for a liquid crystal dropping method, and a method for manufacturing a liquid crystal display panel. [Background technology]

[0002] Conventionally, resin compositions such as liquid crystal sealants for the liquid crystal dropping method have been produced by mixing a curable compound with predetermined amounts of a photopolymerization initiator, a curing agent, a filler, etc. in a planetary mixer, and then further mixing using a three-roll mill or the like (Patent Document 1). However, the three-roll mill process takes a long time, and this production method has the problem of low productivity. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-188720 Summary of the Invention [Problem to be solved by the invention]

[0004] The three-roll process is performed to thoroughly disperse solid components such as fillers and latent hardeners, but the concentration of fillers and latent hardeners in liquid crystal sealants for the liquid crystal drip method is often around 10 to 20% by weight, and the three-roll process is also performed for other components that do not require three-roll processing, which is a factor that lengthens the manufacturing process.

[0005] The present invention aims to provide a manufacturing method that shortens the manufacturing time of a liquid crystal sealant for a liquid crystal dropping method and improves productivity by mixing only some of the components of the liquid crystal sealant using a three-roll mill. [Means for solving the problem]

[0006] That is, the present invention relates to the following [1] to [6]. In this application, "(Numerical value 1) to (Numerical value 2)" indicates that the upper and lower limits are included. Also, "(meth)acrylate" means "acrylate" and / or "methacrylate". [1] a step of mixing a curable compound, a filler, and a latent heat curing agent to obtain a composition (X), wherein the total content of the filler and the latent heat curing agent is 30% by weight or more and 55% by weight or less in the total amount of the curable compound, the filler, and the latent heat curing agent; Obtaining a composition (Y) containing a curable compound; a step of mixing the composition (X) and the composition (Y) at an apparatus temperature of 35 to 45°C to obtain a liquid crystal sealant for a liquid crystal dropping method; A method for producing a liquid crystal sealant for use in a liquid crystal dropping method, comprising: [2] The method for producing a liquid crystal sealant for a liquid crystal dropping method according to the above item [1], wherein the curable resin in the composition (X) contains a compound having a thiol group. [3] The method for producing a liquid crystal sealant for a liquid crystal dropping method according to the above item [1] or [2], wherein in the step of obtaining the composition (X), the step of mixing the curable compound, the filler, and the latent heat curing agent is a step of mixing using a triple roll. [4] The method for producing a liquid crystal sealant for a liquid crystal dropping method according to any one of the preceding items [1] to [3], wherein the step of mixing the composition (X) and the composition (Y) is a step of mixing them using a planetary mixer. [5] The method for producing a liquid crystal sealant for a liquid crystal dropping method according to any one of the above items [1] to [4], further comprising the step of mixing a photoradical polymerization initiator. [6] A method for manufacturing a liquid crystal display panel sealed with a liquid crystal sealant for a liquid crystal dropping method obtained by the manufacturing method according to any one of the preceding items [1] to [5]. [Effects of the Invention]

[0007] The present invention can provide a manufacturing method that shortens the manufacturing time of a liquid crystal sealant for a liquid crystal dropping method and improves productivity because only some of the materials are mixed using a three-roll mill. DETAILED DESCRIPTION OF THE INVENTION

[0008] The liquid crystal sealant for the liquid crystal dropping method of the present invention (hereinafter also simply referred to as "liquid crystal sealant") can be obtained by a production method including the steps of mixing a curable compound, a filler, and a latent heat curing agent to obtain composition (X), obtaining composition (Y) containing the curable compound, and mixing composition (X) and composition (Y) to obtain the liquid crystal sealant for the liquid crystal dropping method.

[0009] The step of obtaining composition (X) is preferably a step of mixing using a planetary mixer and then mixing using a three-roll mill.

[0010] There are no particular limitations on the planetary mixer as long as it has a structure that allows temperature control by flowing water or the like at least around the outer periphery of the kettle, but a mixer equipped with two frame-shaped mixing blades and with a narrow gap between the inner wall of the kettle and the mixing blades is preferred because it has excellent mixing power. Examples include the PLM-series manufactured by Inoue Seisakusho, the PLM-series manufactured by Ashizawa Finetech, and the PVM-series manufactured by Asada Iron Works.

[0011] The triple roll is not particularly limited, but is preferably one that has a structure that allows temperature control by running water or the like inside the roll, and the rollers are preferably made of ceramic, such as the C series manufactured by Inoue Seisakusho and the NR series manufactured by Noritake.

[0012] In composition (X), the total content of the filler and latent curing agent is preferably 30% by weight or more and 55% by weight or less of the total amount of the curable compound, filler, and latent curing agent. If it is less than 30% by weight, the effect of improving productivity compared to conventional manufacturing methods will be small. If it is more than 55% by weight, the fluidity of composition (X) will decrease, which will reduce the workability of mixing with composition (Y).

[0013] The step of obtaining composition (Y) is preferably a step of mixing in a planetary mixer.

[0014] The step of obtaining a liquid crystal sealant for the liquid crystal dropping method is preferably a step of mixing using a planetary mixer. Composition (X) and composition (Y) are preferably mixed at an apparatus temperature of 35°C to 45°C. If the apparatus temperature is below 35°C, resin without filler mixed therein will remain on the wall and bottom of the mixer, preventing uniform mixing, which may result in the viscosity of the resulting liquid crystal sealant being lower than the designed value. If the apparatus temperature is higher than 45°C, the curable compound may react, which may result in the viscosity of the resulting liquid crystal sealant being higher than the designed value.

[0015] In addition to the above steps, the production method of the present invention may also include a degassing step and a filtration step.

[0016] [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, and examples thereof include compounds having a (meth)acrylic group, compounds having an epoxy group, compounds having a maleimide group, and compounds having a thiol group. [Compounds having a (meth)acrylic group] Examples of the compound having a (meth)acrylic group include (meth)acrylate, epoxy (meth)acrylate, urethane (meth)acrylate, and polybutadiene compounds having a (meth)acrylic group.

[0017] [(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.

[0018] [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.

[0019] [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 the hydroxyl group of the component (a) is preferably reacted with 1.1 to 2.0 equivalents, and particularly preferably 1.3 to 2.0 equivalents, of the isocyanate group 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.

[0020] 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) which are reaction products of these diols (a-1) with dibasic acids or their anhydrides (for example, succinic acid, adipic acid, azelaic acid, sebacic acid, dimer acid, isophthalic acid, terephthalic acid, phthalic acid, or anhydrides thereof).

[0021] Specific examples of (b) organic polyisocyanates include tolylene diisocyanate, isophorone diisocyanate, 1,6-hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-cyclohexylmethane 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.

[0022] Specific examples of (c) hydroxyl group-containing (meth)acrylates 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.

[0023] [Polybutadiene compound having (meth)acrylic group] Polybutadiene compounds having a (meth)acrylic group are commercially available, for example, as TEAI-1000 and TE-2000 manufactured by Nippon Soda Co., Ltd.

[0024] [Compounds containing epoxy groups] Examples of the compound having an epoxy group include an epoxy resin and a polybutadiene compound having an epoxy group.

[0025] [Epoxy resin] 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.

[0026] [Polybutadiene compound having epoxy groups] Polybutadiene compounds having epoxy groups are commercially available, for example, as JP-100 and JP-200 manufactured by Nippon Soda Co., Ltd.

[0027] [Compounds containing thiol groups] Examples of compounds having a thiol group 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, 1,8-dimercapto-3,6- Dioxaoctane, 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 Ethylene glycol bis(2-mercaptoacetate), ethylene glycol bis(3-mercaptopropionate), 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) Dipentaerythritol hexakis(3-mercaptopropionate), 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 ethanol 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-mercaptobutyrate) captovalerate), octanediol 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)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), 1,4-bis(3-mercaptobutyryloxy)butane, etc. Among these, preferred are trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptopropionate), dipentaerythritol hexakis(3-mercaptopropionate), 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, and pentaerythritol tetrakis(3-mercaptobutyrate) are preferred, and from the viewpoints of liquid crystal contamination prevention and storage stability at room temperature, 1,3,5-tris(3-mercaptobutyloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione and pentaerythritol tetrakis(3-mercaptobutyrate) having a secondary thiol structure are particularly preferred. These compounds having a thiol group may be produced by known methods, or commercially available compounds may be used. Commercially available compounds include Karenz MT and RTM PE1, BD1, NR1, trimethylolpropane tris(3-mercaptobutyrate), trimethylolethane tris(3-mercaptobutyrate) (all manufactured by Resonac Co., Ltd.), polythiol RTM 340M (manufactured by Toray Fine Chemicals Co., Ltd.), pentaerythritol tetrakis(3-mercaptopropionate) (manufactured by SC Organic Chemicals Co., Ltd.), and the like.

[0028] The curable compound may be one of the above materials or a mixture of two or more of them.

[0029] Furthermore, the curable compound in composition (X) and the curable compound in composition (Y) may be the same or different.

[0030] [Filler] The liquid crystal sealing material of the present invention contains a filler, such as an organic filler or an inorganic filler.

[0031] [Organic filler] Examples of organic fillers include urethane fine particles, acrylic fine particles, styrene fine particles, styrene olefin fine particles, and silicone fine particles. Examples of silicone fine 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 Industries Co., Ltd.) are preferred as urethane fine particles, and Rabalon is preferred as styrene fine particles. RTM T320C, T331C, SJ4400, SJ5400, SJ6400, SJ4300C, SJ5300C, and SJ6300C (manufactured by Mitsubishi Chemical) are preferred, and Septon is the styrene olefin 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. Examples of the silicone fine particles 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 fine particles, particularly preferred are silicone rubber of linear dimethylpolysiloxane crosslinked powder or composite silicone rubber fine particles of silicone resin-coated linear dimethylpolysiloxane crosslinked powder. The organic fillers may be used alone or in combination of two or more.

[0032] [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. Preferred examples include 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. The inorganic fillers may be used alone or in combination of two or more.

[0033] [Latent heat curing agent] The liquid crystal sealant of the present invention can be improved in reactivity by adding a latent heat curing agent. Examples of latent heat curing agents include compounds having a carboxy group bonded to an aromatic ring in the molecule, polyamines, organic acid hydrazides, imidazole compounds, and organic acids. However, the latent heat curing agent is not limited to these. Examples of the latent 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.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')). Examples of organic acids include 2,4-diamino-6(2'-ethyl-4-methylimidazole(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, and 1-cyanoethyl-2-phenyl-3,5-dicyanoethoxymethylimidazole. Examples of organic acids 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(2-carboxymethyl)isocyanurate, tris(2-carboxyethyl)isocyanurate, tris(2-carboxypropyl)isocyanurate, and bis(2-carboxyethyl)isocyanurate.Among these, isophthalic acid dihydrazide, malonic acid dihydrazide, adipic acid dihydrazide, tris(1-hydrazinocarbonylmethyl)isocyanurate, tris(1-hydrazinocarbonylethyl)isocyanurate, tris(2-hydrazinocarbonylethyl)isocyanurate, tris(3-hydrazinocarbonylpropyl)isocyanurate, and 2,4-diamino-6(2'-methylimidazole(1'))ethyl-s-triazine·isocyanuric acid adduct are preferred in terms of the balance between curing reactivity and latency. Latent heat curing agents may be used alone or in combination of two or more.

[0034] [Other ingredients] The liquid crystal sealant of the present invention may further contain, as necessary, additives such as a photoradical polymerization initiator, a thermal radical polymerization initiator, a silane coupling agent, a radical polymerization inhibitor, a pigment, a leveling agent, an antifoaming agent, a solvent, etc. These materials may be mixed in any step among the steps for obtaining composition (X), composition (Y), and the liquid crystal sealant.

[0035] [Photoradical polymerization initiator] The liquid crystal sealing material of the present invention may contain 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-propane, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, camphorquinone, 9-fluorenone, and diphenyl disulfide. Specific examples include IRGACURE RTM 651, 184, 2959, 127, 907, 369, 379EG, 819, 784, 754, 500, OXE01, OXE02, OXE03, OXE04, DAROCURE RTM 1173, LUCIRIN RTMTPO (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 These include OXE01, OXE02, OXE03, OXE04, and the thioxanthone initiator, Kayacure DETX-S. Furthermore, by using an oxime ester initiator in combination with a thioxanthone initiator, both instant curing and light-shielding curing can be achieved. The photoradical polymerization initiators may be used alone or in combination of two or more.

[0036] [Thermal radical polymerization initiator] The liquid crystal sealing material of the present invention contains a thermal radical polymerization initiator, which can improve the curing speed 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, benzopinacol, etc., and benzopinacol is preferably used. For example, an organic peroxide such as 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 RTMIB, IPP, Perocta RTM ND (manufactured by NOF Corporation) and other products are available commercially.

[0037] In addition, commercially available azo compounds include VA-044, 086, V-070, VPE-0201, and VSP-1001 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

[0038] 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 above-mentioned benzopinacol 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 from silicone derivative manufacturers and other commercial sources.

[0039] [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.

[0040] [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 examples of the radical polymerization inhibitor that can be used include quinone-based, piperidine-based, hindered phenol-based, nitroso-based, and polyhydric phenols.Specifically, 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, 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], 2,4,8,1 0-Tetraoxaspiro[5,5]undecane, tetrakis-[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenylpropionate)methane], 1,3,5-tris(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, trade names Adeka STAB LA-81 and Adeka STAB LA-82 (Corporation) Examples of suitable phenolic novolac resins include, but are not limited to, novolac resins made from various phenols such as bisphenol A (manufactured by ADEKA), bisphenol A, allylphenols, brominated bisphenol A, bisphenol F, bisphenol S, and naphthols; phenol novolac resins such as phenol novolac resins having a xylylene skeleton, phenol novolac resins having a dicyclopentadiene skeleton, and phenol novolac resins having a fluorene skeleton; phenol, cresols, ethylphenols, butylphenols, and octylphenols.

[0041] A liquid crystal display panel 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, silicone, 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). The liquid crystal display cell of the present invention can then be obtained by curing the resulting material at 90 to 130°C for 30 minutes to 2 hours, if necessary. The liquid crystal display cell of the present invention thus obtained 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 diameters vary depending on the purpose, but are typically 2 to 8 μm, preferably 4 to 7 μm. The amount of spacers used is typically 0.1 to 4 parts by weight, preferably 0.5 to 2 parts by weight, and more preferably about 0.9 to 1.5 parts by weight, per 100 parts by weight of the liquid crystal sealant of the present invention. [Example]

[0042] 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 by weight.

[0043] [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.

[0044] [Synthesis Example 2] 100 parts (0.28 mol) of commercially available benzopinacol (Tokyo Chemical Industry Co., Ltd.) was dissolved in 350 parts of dimethylformaldehyde. 32 parts (0.4 mol) of pyridine as a base 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%).

[0045] [Examples 1 to 3, Comparative Example 1] [Preparation of composition (X)] The components of composition (X) were mixed in the proportions shown in Table 1 in a planetary mixer at a kettle temperature of 90°C, then cooled to room temperature and mixed using a three-roll mill.

[0046] [Liquidity assessment] The state of the compositions (X) obtained in Examples 1 to 3 and Comparative Example 1 after mixing was confirmed by the following method. Good: When 10 g of the mixed composition was placed in a 30 cc plastic jar (manufactured by Shinto Chemical, no lid) and the jar's spout was placed facing downwards in a 25°C environment, the composition dripped from the spout under its own weight within 5 seconds. ×: When 10 g of the mixed composition was placed in a 30 cc plastic jar (manufactured by Shinto Chemical, no lid) and the jar was placed with the spout facing downwards in an environment of 25°C, the composition did not drip from the spout under its own weight even after 5 seconds had passed, and remained in the jar.

[0047] [Table 1]

[0048] The fluidity was excellent in Examples 1 to 3. On the other hand, the fluidity was poor in Comparative Example 1. If the composition (X) does not have fluidity, it is difficult to charge it into a mixing vessel in the subsequent step.

[0049] [Examples 4 and 5] [Preparation of Composition (Y)] The components of composition (Y) were mixed in the proportions shown in Table 2 in a planetary mixer at a kettle temperature of 90°C.

[0050] [Table 2]

[0051] [Examples 6 to 10, Comparative Examples 2 to 3] [Manufacturing liquid crystal sealants] The components of the liquid crystal sealant were mixed in the proportions shown in Table 3 for 60 minutes using a planetary mixer to obtain a liquid crystal sealant.

[0052] [Mixed evaluation] After mixing for 60 minutes, the residue on the wall of the planetary mixer was checked. ○: No unmixed resin with filler adheres to the wall of the furnace ×: Resin not mixed with filler adheres to the wall of the vessel

[0053] [Viscosity measurement] The viscosity increase rates were measured for the liquid crystal sealants obtained in Examples 6 to 10 and Comparative Examples 2 and 3. The viscosity was measured 20 minutes after the start of mixing and 120 minutes after the start of mixing, and the viscosity increase rate was calculated using the following formula. The viscosity was measured using an R-type viscometer (R115U-type viscometer, manufactured by Toki Sangyo Co., Ltd.) with a measurement cone of 3° x R7.7 and a rotation speed of 5 rpm in an atmosphere of 25°C. Viscosity increase rate = Viscosity 120 minutes after starting mixing / Viscosity 20 minutes after starting mixing 〇: Viscosity increase rate is 0.95 or more and less than 1.02 ×: Viscosity increase rate is 1.02 or more

[0054] [Manufacturing time] The production time for each of the liquid crystal sealants in Examples 6 to 10 and Comparative Examples 2 and 3 is shown in Table 3.

[0055] [Table 3]

[0056] Comparative Example 4 Bisphenol A partial epoxy acrylate, EBECRYL3700, urethane acrylate, Irgacure Oxe04, PN-152L, and Polystop 7300P were mixed in a planetary mixer at a kettle temperature of 90°C, and then the kettle temperature was changed to 20°C, after which Karenz MT PE1, X-24-9163A, 2MAOK-PW, CIC acid-J, KBM-403, and MH-002-J were added and mixed. These were then mixed using a three-roll mill to obtain the liquid crystal sealant of Comparative Example 4, which was produced using a conventional process.

[0057] [Manufacturing time] The production time of the liquid crystal sealant of Comparative Example 4 is shown in Table 4.

[0058] [Table 4]

[0059] [Table 5]

[0060] The results in Tables 3 and 4 reveal that the liquid crystal sealant obtained by the production method of the present invention has a good mixed state, does not increase in viscosity, and can be produced in a short time.

Claims

1. a step of mixing a curable compound, a filler, and a latent heat curing agent to obtain a composition (X), wherein the total content of the filler and the latent heat curing agent is 30% by weight or more and 55% by weight or less in the total amount of the curable compound, the filler, and the latent heat curing agent; Obtaining a composition (Y) containing a curable compound; a step of mixing the composition (X) and the composition (Y) at an apparatus temperature of 35 to 45°C to obtain a liquid crystal sealant for a liquid crystal dropping method; A method for producing a liquid crystal sealant for a liquid crystal dropping method, comprising:

2. 2. The method for producing a liquid crystal sealant for a liquid crystal dropping method according to claim 1, wherein the curable resin in the composition (X) contains a compound having a thiol group.

3. 2. The method for producing a liquid crystal sealant for a liquid crystal dropping method according to claim 1, wherein in the step of obtaining the composition (X), the step of mixing the curable compound, the filler, and the latent heat curing agent is a step of mixing using a triple roll.

4. 2. The method for producing a liquid crystal sealant for a liquid crystal dropping method according to claim 1, wherein the step of mixing the composition (X) and the composition (Y) is a step of mixing them using a planetary mixer.

5. The method for producing a liquid crystal sealant for a liquid crystal dropping method according to claim 1 , further comprising the step of mixing a photoradical polymerization initiator.

6. A method for producing a liquid crystal display panel sealed with a liquid crystal sealant for a liquid crystal dropping method obtained by the method according to any one of claims 1 to 5.

Images