Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K3/00—Materials not provided for elsewhere
  • C09K3/10—Materials in mouldable or extrudable form for sealing or packing joints or covers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
  • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
  • C08F220/10—Esters
  • C08F220/26—Esters containing oxygen in addition to the carboxy oxygen
  • C08F220/32—Esters containing oxygen in addition to the carboxy oxygen containing epoxy radicals
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F222/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a carboxyl radical and containing at least one other carboxyl radical in the molecule; Salts, anhydrides, esters, amides, imides, or nitriles thereof
  • C08F222/10—Esters
  • C08F222/1006—Esters of polyhydric alcohols or polyhydric phenols
  • C08F222/102—Esters of polyhydric alcohols or polyhydric phenols of dialcohols, e.g. ethylene glycol di(meth)acrylate or 1,4-butanediol dimethacrylate
  • C08F222/1025—Esters of polyhydric alcohols or polyhydric phenols of dialcohols, e.g. ethylene glycol di(meth)acrylate or 1,4-butanediol dimethacrylate of aromatic dialcohols
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F222/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a carboxyl radical and containing at least one other carboxyl radical in the molecule; Salts, anhydrides, esters, amides, imides, or nitriles thereof
  • C08F222/10—Esters
  • C08F222/1006—Esters of polyhydric alcohols or polyhydric phenols
  • C08F222/106—Esters of polycondensation macromers
  • C08F222/1067—Esters of polycondensation macromers of alcohol terminated epoxy functional polymers, e.g. epoxy(meth)acrylates
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F290/00—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups
  • C08F290/02—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups on to polymers modified by introduction of unsaturated end groups
  • C08F290/06—Polymers provided for in subclass C08G
  • C08F290/064—Polymers containing more than one epoxy group per molecule
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G59/00—Polycondensates containing more than one epoxy group per molecule; Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups
  • C08G59/18—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing
  • C08G59/20—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing characterised by the epoxy compounds used
  • C08G59/22—Di-epoxy compounds
  • C08G59/223—Di-epoxy compounds together with monoepoxy compounds
• • G—PHYSICS
  • G02—OPTICS
  • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
  • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
  • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
  • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
  • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
  • G02F1/1333—Constructional arrangements; Manufacturing methods
  • G02F1/1339—Gaskets; Spacers; Sealing of cells
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K2200/00—Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
  • C09K2200/06—Macromolecular organic compounds, e.g. prepolymers
  • C09K2200/0615—Macromolecular organic compounds, e.g. prepolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • C09K2200/0625—Polyacrylic esters or derivatives thereof
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K2200/00—Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
  • C09K2200/06—Macromolecular organic compounds, e.g. prepolymers
  • C09K2200/0645—Macromolecular organic compounds, e.g. prepolymers obtained otherwise than by reactions involving carbon-to-carbon unsaturated bonds
  • C09K2200/0647—Polyepoxides

Definitions

• the present invention relates to a sealant for liquid crystal display elements.
• the present invention also relates to a liquid crystal display element using the sealant for liquid crystal display elements.
• liquid crystal display elements such as liquid crystal display cells
• curable resin compositions such as those disclosed in Patent Document 1 and Patent Document 2
• a method called the dripping method is used, which uses water as a sealant.
• a sealant is applied to one of two electrode-attached substrates to form a frame-shaped seal pattern.
• microdroplets of liquid crystal are dropped into the seal frame of the substrate, the other substrate is placed on top of the other substrate under vacuum, and the sealant is cured by light irradiation or heating to produce a liquid crystal display element.
• this dripping method is the mainstream method for manufacturing liquid crystal display elements.
• a liquid crystal display element is manufactured by forming a plurality of cells all at once on a mother glass and then dividing each cell.
• An object of the present invention is to provide a sealant for liquid crystal display elements that can suppress light leakage even when used in large-sized liquid crystal display elements, and has excellent transparency of the cured product and excellent adhesiveness to alignment films. shall be.
• Another object of the present invention is to provide a liquid crystal display element using the sealant for liquid crystal display elements.
• the present disclosure 1 is a sealant for a liquid crystal display element containing a curable resin, a photopolymerization initiator, and a thermosetting agent, and after applying the sealant for a liquid crystal display element before curing to a glass substrate. After compressing for 60 seconds by applying a force of 1000 mN/min in the thickness direction and releasing the compression, the amount of displacement from the glass substrate at the time when the force becomes 0 mN is defined as D1, and the glass substrate 2 minutes after D1 measurement.
• a sealant for liquid crystal display elements which has a recovery rate expressed as a percentage of D2/D1, where D2 is the amount of displacement from be.
• the present disclosure 2 is the sealant for a liquid crystal display element according to the present disclosure 1, in which the cured product has a glass transition temperature of 40° C. or higher.
• Present disclosure 3 is the sealant for a liquid crystal display element according to present disclosure 1 or 2, in which the content of the component that is solid at 25° C. is 10% by weight or less.
• the present disclosure 4 is the sealant for a liquid crystal display element according to the present disclosure 1, 2, or 3, which has an average visible light transmittance of 50% or more in a cured product having a thickness of 4.0 ⁇ m.
• the present disclosure 5 is a liquid crystal display element having a cured product of the liquid crystal display element sealant of the present disclosure 1, 2, 3, or 4. The present invention will be explained in detail below.
• the inventor has discovered that the cause of light leakage when manufacturing large liquid crystal display elements is a phenomenon called springback, in which the sealant compressed when bonding substrates tries to return to its original shape, and It was thought that this was due to curing shrinkage during curing of the agent, which caused an optical path length difference due to a gap defect in the liquid crystal display element. In particular, we believe that springback has become more noticeable as mother glass becomes larger, and the time required to bond the substrates and the time from bonding the substrates to curing the sealant becomes longer. Ta.
• the present inventor set the recovery rate of a sealant for liquid crystal display elements containing a curable resin, a photopolymerization initiator, and a thermosetting agent to 110% or less when measured under specific conditions, and set the cure shrinkage rate during curing to 110% or less. We considered setting it to 5.0% or less.
• the sealant for liquid crystal display elements of the present invention is prepared by applying the above-mentioned sealant for liquid crystal display elements before curing to a glass substrate, compressing it for 60 seconds by applying a force of 1000 mN/min in the thickness direction, and then releasing the compression. Then, when the amount of displacement from the glass substrate at the time when the force becomes 0 mN is D1, and the amount of displacement from the glass substrate 2 minutes after D1 measurement is D2, D2/D1 is the recovery rate expressed as a percentage. is 110% or less. Since the recovery rate is 110% or less and the curing shrinkage rate during curing is 5.0% or less, the sealant for liquid crystal display elements of the present invention can be used in large-sized liquid crystal display elements.
• a preferable upper limit of the recovery rate is 107%, and a more preferable upper limit is 105%. Further, although there is no particular preferable lower limit for the above-mentioned recovery rate, the practical lower limit is 100%. Note that the above restoration rate is measured by the following method. That is, first, a sealant for liquid crystal display elements containing 20% by weight of polydivinylbenzene particles (manufactured by Sekisui Chemical Co., Ltd., "Micro Pearl SP") having an average particle diameter of 4 ⁇ m as a gap agent is applied to a glass substrate.
• the applied liquid crystal display element sealant was compressed for 60 seconds by applying a force of 1000 mN/min in the thickness direction using a compression testing machine, and after measuring the displacement D1 from the glass substrate, the compression was released. Then, by measuring the displacement D2 after waiting for 2 minutes, the above-mentioned restoration rate can be derived.
• the compression tester for example, FISCHERSCOPE HM2000 (manufactured by Fisher Instruments) can be used.
• the sealant for liquid crystal display elements of the present invention has a curing shrinkage rate of 5.0% or less during curing. Since the curing shrinkage rate during curing is 5.0% or less and the above-mentioned recovery rate is 110% or less, the sealant for liquid crystal display elements of the present invention can be used in large-sized liquid crystal display elements. Even in such cases, light leakage can be suppressed, and the cured product has excellent transparency and adhesion to the alignment film.
• the preferable upper limit of the curing shrinkage rate during curing is 4.0%, and the more preferable upper limit is 3.0%. Further, although there is no particularly preferable lower limit for the curing shrinkage rate during curing, the practical lower limit is 1.0%.
• the lower limit of the glass transition temperature of the cured product is preferably 40°C. Since the glass transition temperature of the cured product is 40° C. or higher, the sealant for liquid crystal display elements of the present invention has excellent adhesiveness to alignment films. A more preferable lower limit of the glass transition temperature of the cured product is 50°C. Further, from the viewpoint of adhesive properties, etc., the upper limit of the glass transition temperature of the cured product is preferably 130°C, and more preferably 105°C.
• the glass transition temperature of the cured product is defined as the temperature of the maximum value of loss tangent (tan ⁇ ) when dynamic viscoelasticity is measured at -80 to 200°C and 10 Hz using a dynamic viscoelasticity measuring device.
• a sealing compound for a liquid crystal display element is irradiated with ultraviolet rays of 100 mW/cm 2 for 30 seconds, and then cured by heating at 120° C. for 1 hour.
• the sealant for liquid crystal display elements of the present invention contains a curable resin.
• the curable resin preferably includes a curable resin having a flexible skeleton, since this facilitates setting the curing shrinkage rate at the time of curing within the above-mentioned range. Furthermore, by including the curable resin having the above-mentioned flexible skeleton, the obtained sealant for liquid crystal display elements has excellent adhesiveness to the alignment film.
• the curable resin having a flexible skeleton examples include (meth)acrylic compounds having a flexible skeleton, epoxy compounds having a flexible skeleton, and the like.
• the curable resin preferably contains at least one selected from the group consisting of the (meth)acrylic compound having the flexible skeleton and the epoxy compound having the flexible skeleton.
• (meth)acrylic means acrylic or methacryl
• the above-mentioned "(meth)acrylic compound” means a compound having a (meth)acryloyl group
• the above-mentioned "(meth)acryloyl ” means acryloyl or methacryloyl.
• Examples of the (meth)acrylic compound having a flexible skeleton include long-chain (meth)acrylic compounds, (meth)acrylic compounds having a rubber structure, urethane-modified (meth)acrylic compounds, and the like.
• Examples of the long-chain (meth)acrylic compounds include alkylene oxide-modified (meth)acrylic compounds, caprolactone-modified (meth)acrylic compounds, and the like.
• Examples of the (meth)acrylic compound having the above-mentioned rubber structure include (meth)acrylic modified butadiene rubber, (meth)acrylic modified isoprene rubber, and the like.
• urethane-modified (meth)acrylic compound examples include aliphatic urethane (meth)acrylate, aromatic urethane (meth)acrylate, and the like.
• (meth)acrylate means acrylate or methacrylate.
• Examples of the epoxy compound having a flexible skeleton include long-chain epoxy compounds, epoxy compounds having a rubber structure, and the like.
• Examples of the long-chain epoxy compound include alkylene oxide-modified epoxy compounds, alkylene-modified epoxy compounds, and the like.
• Examples of the epoxy compound having the rubber structure include butadiene-modified epoxy compounds, terminal carboxyl group-containing polybutadiene-acrylonitrile (CTBN)-modified epoxy compounds, and epoxy group-containing acrylic rubber.
• examples of other epoxy compounds having a flexible skeleton include urethane-modified epoxy compounds, rubber particle-dispersed epoxy compounds, and the like.
• the curable resin preferably contains a caprolactone-modified (meth)acrylic compound, and more preferably contains a caprolactone-modified epoxy (meth)acrylate.
• epoxy (meth)acrylate refers to a compound obtained by reacting all epoxy groups in an epoxy compound with (meth)acrylic acid.
• the above-mentioned curable resin having a flexible skeleton may be used alone, or two or more types may be used in combination.
• the above-mentioned curable resin may contain other curable resins other than the above-mentioned curable resin having a flexible skeleton, for the purpose of improving the adhesiveness and low liquid crystal contamination of the obtained sealant for liquid crystal display elements.
• a (meth)acrylic compound other than the above-mentioned (meth)acrylic compound having a flexible skeleton or an epoxy compound other than the above-mentioned epoxy compound having a flexible skeleton is suitably used.
• the preferable lower limit of the content of the curable resin having a flexible skeleton in 100 parts by weight of the curable resin is 40 parts by weight, and the preferable upper limit is 80 parts by weight.
• Examples of the other (meth)acrylic compounds mentioned above include epoxy (meth)acrylate obtained by reacting (meth)acrylic acid with an epoxy compound that does not have a flexible skeleton, (meth)acrylic acid, and a hydroxyl group.
• Examples include (meth)acrylic acid ester compounds obtained by reacting with a compound having no flexible skeleton. Among them, epoxy (meth)acrylate is preferred.
• the other (meth)acrylic compounds mentioned above preferably have two or more (meth)acryloyl groups in the molecule from the viewpoint of high reactivity.
• epoxy (meth)acrylate which is the other (meth)acrylic compound mentioned above, for example, an epoxy compound without a flexible skeleton and (meth)acrylic acid are reacted in the presence of a basic catalyst according to a conventional method.
• a basic catalyst examples include those obtained by.
• Examples of epoxy compounds without flexible skeletons that are raw materials for synthesizing epoxy (meth)acrylate, which is the other (meth)acrylic compound mentioned above, include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, 2,2'-diallylbisphenol A type epoxy resin, hydrogenated bisphenol type epoxy resin, propylene oxide added bisphenol A type epoxy resin, resorcinol type epoxy resin, biphenyl type epoxy resin, diphenyl ether type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, phenol novolac type epoxy resin, orthocresol novolac type epoxy resin, dicyclopentadiene novolac type epoxy resin, biphenyl novolac type epoxy resin, naphthalene phenol novolac type epoxy resin, Examples include glycidylamine type epoxy resins and glycidyl ester compounds.
• Examples of the above-mentioned other epoxy compounds include those similar to the above-mentioned epoxy compounds that do not have a flexible skeleton and serve as raw materials for synthesizing epoxy (meth)acrylate, which is the other (meth)acrylic compound.
• the curable resin may contain a compound having an epoxy group and a (meth)acryloyl group in one molecule as the other epoxy compound.
• examples of such compounds include, for example, parts obtained by reacting the epoxy groups of a part of an epoxy compound that has two or more epoxy groups in one molecule and does not have a flexible skeleton with (meth)acrylic acid.
• examples include (meth)acrylic modified epoxy resins.
• the other curable resins mentioned above may be used alone or in combination of two or more.
• the preferable lower limit of the average value of the molecular weight based on the weight fraction of the constituent components is 500, and the preferable upper limit is 2,000.
• the average value of the molecular weight is within this range, the obtained sealant for liquid crystal display elements can suppress shrinkage during curing while maintaining a Tg at which adhesiveness to the alignment film can be maintained.
• a more preferable lower limit of the average molecular weight is 700, and a more preferable upper limit is 1,500.
• the above-mentioned "molecular weight” is the molecular weight determined from the structural formula for compounds whose molecular structure is specified, but for compounds with a wide distribution of polymerization degree and compounds whose modification site is unspecified, It may be expressed using number average molecular weight.
• the above-mentioned number average molecular weight is a value determined by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent at a measurement temperature of 25° C. and converted to polystyrene. Examples of columns for measuring the number average molecular weight in terms of polystyrene by GPC include Shodex LF-804 (manufactured by Showa Denko).
• the sealant for liquid crystal display elements of the present invention contains a photopolymerization initiator.
• the photopolymerization initiator include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, and thioxanthone compounds.
• Specific examples of the photopolymerization initiator include 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, and 2-(dimethylamino).
• the preferable lower limit of the content of the photopolymerization initiator is 0.01 and the preferable upper limit is 10 parts by weight based on 100 parts by weight of the curable resin.
• the resulting curable resin composition has better storage stability and photocurability.
• a more preferable lower limit of the content of the photopolymerization initiator is 0.1 parts by weight, and a more preferable upper limit is 5 parts by weight.
• the sealant for liquid crystal display elements of the present invention may contain a thermal polymerization initiator.
• the thermal polymerization initiator include those made of azo compounds, organic peroxides, and the like.
• initiators made of polymer azo compounds (hereinafter also referred to as "polymer azo initiators") are preferred.
• the polymer azo compound refers to a compound having an azo group, which generates a radical capable of curing a (meth)acryloyl group by heat, and has a number average molecular weight of 300 or more.
• the preferable lower limit of the number average molecular weight of the polymeric azo compound is 1,000, and the preferable upper limit is 300,000.
• the number average molecular weight of the polymeric azo compound is within this range, it can be easily mixed with the curable resin while suppressing liquid crystal contamination.
• a more preferable lower limit of the number average molecular weight of the polymer azo compound is 5,000, a more preferable upper limit is 100,000, an even more preferable lower limit is 10,000, and an even more preferable upper limit is 90,000.
• Examples of the above-mentioned polymeric azo compounds include those having a structure in which a plurality of units such as polyalkylene oxide and polydimethylsiloxane are bonded via an azo group.
• the polymeric azo compound having a structure in which a plurality of units such as polyalkylene oxide are bonded via an azo group is preferably one having a polyethylene oxide structure.
• Specific examples of the above-mentioned polymer azo compounds include polycondensates of 4,4'-azobis(4-cyanopentanoic acid) and polyalkylene glycol, and 4,4'-azobis(4-cyanopentanoic acid).
• Examples include polycondensates of polydimethylsiloxane and polydimethylsiloxane having terminal amino groups.
• polymeric azo compounds commercially available ones include, for example, VPE-0201, VPE-0401, VPE-0601, VPS-0501, and VPS-1001 (all manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). It will be done.
• examples of commercially available azo compounds that are not polymers include V-65 and V-501 (both manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.).
• organic peroxide examples include ketone peroxide, peroxyketal, hydroperoxide, dialkyl peroxide, peroxy ester, diacyl peroxide, peroxydicarbonate, and the like.
• the preferable lower limit of the content of the thermal polymerization initiator is 0.01 parts by weight and the preferable upper limit is 10 parts by weight based on 100 parts by weight of the curable resin.
• the content of the polymerization initiator is within this range, the obtained sealant for liquid crystal display elements suppresses liquid crystal contamination and has excellent storage stability and thermosetting properties.
• a more preferable lower limit of the content of the polymerization initiator is 0.1 parts by weight, and a more preferable upper limit is 5 parts by weight.
• the sealant for liquid crystal display elements of the present invention contains a thermosetting agent.
• the thermosetting agent includes an amine adduct compound.
• Examples of the above-mentioned amine adduct compounds include adducts obtained by reacting an amine compound such as an imidazole compound or a primary to tertiary amine with an epoxy compound.
• amine adduct compounds commercially available ones include, for example, the amine adduct compound manufactured by Ajinomoto Fine Techno Co., Ltd., the amine adduct compound manufactured by Shikoku Chemical Industry Co., Ltd., the amine adduct compound manufactured by Mitsubishi Chemical Company, and the amine adduct compound manufactured by ADEKA Company.
• examples include adduct compounds and amine adduct compounds manufactured by T&K TOKA.
• Examples of the above amine adduct compounds manufactured by Ajinomoto Fine Techno include Amicure PN-23, Amicure PN-23J, Amicure PN-H, Amicure PN-31, Amicure PN-31J, Amicure PN-40, Amicure PN-40J, Examples include Amicure PN-50, Amicure PN-F, Amicure MY-24, and Amicure MY-H.
• Examples of the amine adduct compound manufactured by Shikoku Kasei Kogyo Co., Ltd. include P-0505.
• Examples of the amine adduct compound manufactured by Mitsubishi Chemical include P-200.
• Examples of the amine adduct compounds manufactured by ADEKA include ADEKA Hardener EH-5001P, ADEKA Hardener EH-5057PK, ADEKA Hardener EH-5030S, ADEKA Hardener EH-5011S, and the like.
• Examples of the amine adduct compounds manufactured by T&K TOKA include FujiCure FXR-1036, FujiCure FXR-1020, and FujiCure FXR-1081.
• thermosetting agents other than the above-mentioned amine adduct compounds include organic acid hydrazides, polyhydric phenol compounds, acid anhydrides, and the like. Among them, organic acid hydrazides are preferably used.
• organic acid hydrazide examples include 1,3-bis(hydrazinocarboethyl)-5-isopropylhydantoin, sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, malonic acid dihydrazide, and the like.
• thermosetting agents may be used alone or in combination of two or more.
• the preferable lower limit of the content of the thermosetting agent is 0.5 parts by weight and the preferable upper limit is 10 parts by weight based on 100 parts by weight of the curable resin.
• the obtained sealant for liquid crystal display elements has excellent thermosetting properties while maintaining excellent applicability and storage stability, and also has the above-mentioned curing shrinkage. It becomes easier to adjust the rate and the restoration rate to the ranges mentioned above.
• a more preferable lower limit of the content of the thermosetting agent is 1 part by weight, and a more preferable upper limit is 5 parts by weight.
• the sealant for a liquid crystal display element of the present invention preferably does not contain an inorganic filler, since this makes it easier to maintain the recovery rate within the above-mentioned range. Moreover, by not containing the above-mentioned inorganic filler, the obtained sealant for liquid crystal display elements becomes suitable for liquid crystal display elements that require transparency in the sealant for liquid crystal display elements from the viewpoint of design and the like.
• the sealant for a liquid crystal display element of the present invention may contain an organic filler from the viewpoint of improving viscosity, improving adhesiveness, etc., within a range that does not impede the object of the present invention.
• organic filler include polyester fine particles, polyurethane fine particles, vinyl polymer fine particles, and acrylic polymer fine particles.
• the preferable upper limit of the content of the organic filler in 100 parts by weight of the sealant for liquid crystal display elements of the present invention is 20 parts by weight.
• the content of the organic filler is within this range, it becomes easier to adjust the curing shrinkage rate and the recovery rate to the above ranges while exhibiting effects such as improving viscosity.
• a more preferable upper limit of the content of the organic filler is 15 parts by weight.
• the sealant for liquid crystal display elements of the present invention contains a silane coupling agent.
• the silane coupling agent mainly serves as an adhesion aid for good adhesion between the liquid crystal display element sealant and the substrate.
• the silane coupling agent for example, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, etc. are preferably used.
• the preferable lower limit of the content of the silane coupling agent in 100 parts by weight of the sealant for liquid crystal display elements of the present invention is 0.1 parts by weight, and the preferable upper limit is 10 parts by weight.
• the content of the silane coupling agent is within this range, the obtained sealant for liquid crystal display elements has an excellent effect of improving adhesiveness while suppressing occurrence of liquid crystal contamination.
• a more preferable lower limit of the content of the silane coupling agent is 0.3 parts by weight, and a more preferable upper limit is 5 parts by weight.
• the sealant for liquid crystal display elements of the present invention may further contain additives such as stress relaxers, reactive diluents, thixotropic agents, curing accelerators, antifoaming agents, leveling agents, and polymerization inhibitors, as necessary. May be contained.
• the content of components that are solid at 25° C. is preferably 10% by weight or less.
• the content of the component that is solid at 25° C. is 10% by weight or less, it becomes easier to set the above-mentioned recovery rate within the above-mentioned range.
• the practical lower limit is 3% by weight.
• the sealing compound for liquid crystal display elements of the present invention for example, using a mixer, a curable resin, a photopolymerization initiator, a thermosetting agent, and a silane coupling agent added as necessary may be used.
• a method of mixing with additives such as.
• the mixer include a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, and a three-roll mixer.
• the cured product having a thickness of 4.0 ⁇ m has an average visible light transmittance of 50% or more.
• the sealant for liquid crystal display elements can be suitably used for liquid crystal display elements that require transparency from the viewpoint of design and the like.
• a more preferable lower limit of the average transmittance of visible light is 70%. Note that the above visible light transmittance can be measured using a spectrophotometer over a wavelength range of 380 to 780 nm. Examples of the spectrophotometer include U-3000 (manufactured by Hitachi, Ltd.).
• the cured product used to measure the visible light transmittance was a sealing compound for liquid crystal display elements that was cured by irradiating it with ultraviolet rays of 100 mW/cm 2 for 30 seconds and then heating it at 120°C for 1 hour. It will be done.
• a vertically conductive material can be manufactured.
• the conductive fine particles metal balls, resin fine particles with a conductive metal layer formed on the surface, etc. can be used.
• those in which a conductive metal layer is formed on the surface of resin fine particles are preferable because the excellent elasticity of the resin fine particles allows conductive connection without damaging the transparent substrate or the like.
• a liquid crystal display element having a cured product of the sealant for a liquid crystal display element of the present invention is also one of the present invention.
• a liquid crystal dropping method is suitably used, and specific examples include a method having the following steps. It will be done. First, a step of forming a frame-shaped seal pattern is performed by applying the sealant for a liquid crystal display element of the present invention to one of two transparent substrates having electrodes such as an ITO thin film by screen printing, dispenser coating, or the like. Next, a step of applying droplets of liquid crystal to the entire area within the frame of the seal pattern and overlapping the other transparent substrate under vacuum is performed. Thereafter, a liquid crystal display element can be obtained by performing a step of temporarily curing the sealant by irradiating the seal pattern with light such as ultraviolet rays, and a step of heating the temporarily hardened sealant to fully cure it. can.
• a sealant for a liquid crystal display element that can suppress light leakage even when used in a large-sized liquid crystal display element, and has excellent transparency of a cured product and excellent adhesiveness to an alignment film. Can be done. Further, according to the present invention, it is possible to provide a liquid crystal display element using the sealant for liquid crystal display elements.
• curable resin A 232 parts by weight of 2-hydroxyethyl acrylate, 336 parts by weight of 4-methylcyclohexane-1,2-dicarboxylic anhydride, and 0.1 part by weight of hydroquinone as a polymerization inhibitor were added to a reaction flask, and the mixture was heated using a mantle heater. The mixture was stirred at 90°C for 5 hours. Next, 340 parts by weight of bisphenol A diglycidyl ether and 0.5 parts by weight of triphenylphosphine were added to the obtained reaction product, and the mixture was stirred at 110°C for 5 hours to form a compound (cured) represented by the following formula (1). Resin A) was obtained. The structure of the obtained curable resin A was confirmed by 1 H-NMR, 13 C-NMR, and FT-IR.
• curable resin B 105 parts by weight of 2-hydroxyethyl acrylate, 114 parts by weight of ⁇ -caprolactone, and 0.2 parts by weight of hydroquinone as a polymerization inhibitor were added to the reaction flask, and after stirring at 90°C for 5 hours using a mantle heater, 148 parts by weight of phthalic anhydride was added, and the mixture was further stirred for 5 hours. Next, 170 parts by weight of bisphenol A diglycidyl ether was added to the obtained reaction product and stirred at 90°C for 5 hours to obtain a mixture containing the compound (curable resin B) represented by the following formula (2). Ta. The structure of the obtained curable resin B was confirmed by 1 H-NMR, 13 C-NMR, and FT-IR.
• curable resin C 31.2 parts by weight of bisphenol F diglycidyl ether, 1.3 parts by weight of triphenylphosphine, 0.1 parts by weight of hydroquinone, and 7.2 parts by weight of acrylic acid were added to a reaction flask, and the mixture was heated at 100°C. The mixture was heated and stirred for hours. Next, the obtained reaction product was washed three times with 100 mL of water to obtain a mixture containing a compound (curable resin C) represented by the following formula (3). The structure of the obtained curable resin C was confirmed by 1 H-NMR, 13 C-NMR, and FT-IR.
• Examples 1 to 8, Comparative Examples 1 to 8 According to the compounding ratio listed in Table 1, each material was stirred using a planetary stirring device and then uniformly mixed using a three-roll ceramic roll to produce liquid crystal display elements of Examples 1 to 8 and Comparative Examples 1 to 8. A sealant for use was obtained.
• As the planetary stirring device Awatori Rentaro (manufactured by Shinky Co., Ltd.) was used. Polydivinylbenzene particles (manufactured by Sekisui Chemical Co., Ltd., "Micropearl SP-204") with an average particle diameter of 4 ⁇ m were added as a gap agent to the obtained sealant for liquid crystal display elements so that the content was 20% by weight.
• a liquid crystal display element sealant containing a gap agent was applied to the glass substrate using a dispenser in a line width of 1.5 mm with a cross-sectional area of about 6000 ⁇ m 2 .
• the glass substrate is an alkali-free glass with ITO and has a length of 55 mm, a width of 45 mm, and a thickness of 0.7 mm.
• a force of 1000 mN/min was applied in the thickness direction of the drawn seal using a compression testing machine (FISCHERSCOPE HM2000 (manufactured by Fisher Instruments)) to compress it for 60 seconds.
• each of the obtained sealants for liquid crystal display elements was irradiated with ultraviolet rays (wavelength 365 nm) at 100 mW/cm 2 for 30 seconds using a metal halide lamp, and then heated at 120°C for 1 hour to obtain a thickness of 0.35 mm. A cured product was obtained. The specific gravity at 25° C.
• the other glass substrate was bonded to the other glass substrate via a sealing agent, and left to stand for 5 minutes. Thereafter, after irradiating with ultraviolet rays (wavelength: 365 nm) at 100 mW/cm 2 for 30 seconds using a metal halide lamp, the liquid crystal display element sealant was cured by heating at 120° C. for 1 hour to obtain a test piece. For each of the obtained test pieces, the gap distance was measured using OLS4500 (manufactured by OLYMPUS). Measurements were made at 20 points for each test piece.
• ⁇ and minimum points of the distance between gaps are both within ⁇ 10% of the average value, mark it as “ ⁇ ”; at least one of the maximum and minimum points is outside the range of ⁇ 10% of the average value.
• the average transmittance of visible light (wavelength 380 to 780 nm) was measured for the obtained test piece using a spectrophotometer (manufactured by Hitachi, Ltd., "U-3000").
• the transparency of the cured product is evaluated as " ⁇ " when the average transmittance of visible light is 50% or more, " ⁇ " when it is 20% or more and less than 50%, and "x" when it is less than 20%.
• the gender was evaluated.
• An imide resin was spin-coated on a glass substrate with an ITO thin film, prebaked at 80°C, and then fired at 230°C to produce a substrate with an alignment film.
• As the imide resin SE7492 (manufactured by Nissan Chemical Co., Ltd.) was used. 1% by weight of polydivinylbenzene particles (manufactured by Sekisui Chemical Co., Ltd., "Micropearl SP-204”) with an average particle diameter of 4 ⁇ m was added to each sealant for liquid crystal display elements obtained in Examples and Comparative Examples as a gap agent. The mixture was added so as to be uniformly dispersed using a planetary stirring device.
• a small drop of a liquid crystal display element sealant containing a gap agent was dropped onto the alignment film of the alignment film-coated substrate.
• a substrate with an alignment film on which a sealant for liquid crystal display elements has been dropped is pasted with another substrate with an alignment film in a cross shape via a sealant for liquid crystal display elements, and ultraviolet rays (wavelength: 100 mW/cm 2 ) are applied using a metal halide lamp. 365 nm) for 30 seconds, and then heated at 120° C. for 1 hour to obtain a test piece.
• the strength (peel strength) when the substrate peels off is measured using an autograph AGS-X (manufactured by Shimadzu Corporation).
• a sealant for a liquid crystal display element that can suppress light leakage even when used in a large-sized liquid crystal display element, and has excellent transparency of a cured product and excellent adhesiveness to an alignment film. Can be done. Further, according to the present invention, it is possible to provide a liquid crystal display element using the sealant for liquid crystal display elements.

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• 2023
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