JP7281224B2 - Sealant for liquid crystal drop method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a sealant for a liquid crystal dropping method.

In the manufacturing method of the liquid crystal display element, the dropping method is a method in which a panel can be manufactured by directly dropping the liquid crystal in the closed loop of the sealant under vacuum, bonding them together, and releasing the vacuum. This dripping method has many advantages such as a reduction in the amount of liquid crystal used and a shortened injection time of the liquid crystal into the panel, and is currently the mainstream method for manufacturing liquid crystal panels using large substrates. In the method including the dropping method, the sealant and the liquid crystal are applied, and after bonding, the gap is formed, the alignment is performed, and the sealant is cured mainly by ultraviolet curing.

Patent Document 1 describes an epoxy resin obtained by adding an alkylene carbonate or a haloalcohol compound to a phenolic compound having one or more phenolic hydroxyl groups and further glycidyl etherifying the epoxy resin as a raw material for a sealant for a liquid crystal dropping method, and this epoxy resin. is modified with a carboxylic acid, a carboxylic acid anhydride, or a phenol compound (Patent Document 1).

JP 2017-002246 A

In recent years, as the frame of liquid crystal panels has become narrower, there has been a tendency for the sealant and the alignment film to overlap. Accordingly, adhesiveness to the alignment film is required. At the same time, the line width of the sealant tends to be narrowed. Therefore, low moisture permeability is required.

Accordingly, an object of the present invention is to provide a sealant for a liquid crystal dropping method, which has excellent adhesiveness to an alignment film and gives a cured product having excellent low moisture permeability.

The present invention has the following configurations.
[1] A sealant for a liquid crystal dropping method containing a curable resin, a photoinitiator and a thermosetting agent,
the curable resin comprises an oligomer A and an oligomer B;
Oligomer A is a compound obtained by partially (meth)acrylic modifying an epoxy resin having an epoxy equivalent of 200 g/epo or more and an aromatic ring weight of 0.43 or more,
Oligomer B is a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol AD type epoxy resin, a compound obtained by partially (meth)acrylic modifying a bisphenol A type epoxy resin, or a partially (meth)acrylic modifying bisphenol F type epoxy resin. A sealant for a liquid crystal dropping method, which is one or more selected from the group consisting of a compound and a compound obtained by partially (meth)acrylic modifying a bisphenol AD type epoxy resin.
[2] The sealant for liquid crystal dropping method according to [1], wherein the oligomer A has three or more benzene rings in one molecule.
[3] The sealant for liquid crystal dropping method according to [1] or [2], wherein the oligomer A has a bisphenol F type structure.
[4] The sealant for a liquid crystal dropping method according to any one of [1] to [3], wherein the oligomer B is a bisphenol F type epoxy resin or a partially (meth)acryl-modified compound of a bisphenol F type epoxy resin.

ADVANTAGE OF THE INVENTION According to this invention, the adhesiveness with respect to an alignment film is excellent, and the sealing compound for liquid crystal dripping methods which gives the hardened|cured material which is excellent in low moisture permeability is provided.

Preferred embodiments of the present invention are described below. As used herein, "glycidyl group" means a 2,3-epoxypropyl group. "Methylglycidyl group" means a 2,3-epoxy-2-methylpropyl group. "Epoxy group" includes at least one of glycidyl group and methylglycidyl group. "(Meth)acryloyl group" means at least one of acryloyl group (CH ₂ =CH ₂ -C(=O)-) and methacryloyl group (CH ₂ =CH(CH ₃ )-C(=O)-) include. "Optionally substituted" means "substituted or unsubstituted."

[Sealant for Liquid Crystal Dropping Method]
The sealing agent for the liquid crystal dropping method contains a curable resin, a photoinitiator and a thermosetting agent, the curable resin contains an oligomer A and an oligomer B, the oligomer A has an epoxy equivalent of 200 g/epo or more, and is a compound obtained by partially (meth)acrylic modifying an epoxy resin having an aromatic ring content of 0.43 or more, and oligomer B is a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol AD type epoxy resin, a bisphenol A type epoxy resin. One selected from the group consisting of a compound obtained by partially (meth)acrylic modifying an epoxy resin, a compound obtained by partially (meth)acrylic modifying a bisphenol F type epoxy resin, and a compound obtained by partially (meth)acrylic modifying a bisphenol AD type epoxy resin. That's it.

(Curable resin)
The curable resin includes Oligomer A and Oligomer B.

<Oligomer A>
Oligomer A is a compound obtained by partially (meth)acrylic-modifying an epoxy resin having an epoxy equivalent of 200 g/epo or more and an aromatic ring weight of 0.43 or more (hereinafter also referred to as "raw material epoxy resin"). be. Here, "partially (meth)acryl-modified" the epoxy resin means that a part of the epoxy group of the epoxy resin is (meth)acryl-modified.

<< raw material epoxy resin >>
<<<epoxy equivalent>>>
The epoxy equivalent weight of the raw material epoxy resin is 200 g/epo or more. By using a raw material epoxy resin having such an epoxy equivalent, the concentration of functional groups in one molecule of the oligomer A is lowered, and a sealant for a liquid crystal dripping method having excellent adhesiveness to an alignment film can be obtained. The epoxy equivalent weight of the starting epoxy resin is preferably 200-400 g/epo, more preferably 230-330 g/epo, and particularly preferably 260-320 g/epo. In this specification, the epoxy equivalent is determined according to JISK7236:2001 (corresponding to ISO3001:1999).

<<<Amount of aromatic rings>>>
The aromatic ring content of the raw material epoxy resin is 0.43 or more. By combining the oligomer A obtained using the starting material epoxy resin having such an aromatic ring content with the oligomer B described later, a sealant for liquid crystal dropping method excellent in low moisture permeability can be obtained. The aromatic ring content of the starting epoxy resin is preferably 0.43 to 0.60, more preferably 0.43 to 0.55, and particularly preferably 0.48 to 0.53.

In the present specification, the aromatic ring content means the proportion of the aromatic ring structure in the raw material epoxy resin. That is, the aromatic ring content is a value obtained by the following formula (Equation 1).
Aromatic ring weight = total number of molecular weights of aromatic ring structures in one molecule of raw material epoxy resin/molecular weight of one molecule of raw material epoxy resin (Equation 1)

Also, the molecular weight of the aromatic ring structure is based on the weight of the carbon atoms that constitute the aromatic ring. For example, a group having one benzene ring, such as a phenyl group and a phenylene group, has a total molecular weight of carbon atoms (ie, 72) constituting the benzene ring (a ring having 6 carbon atoms). In addition, condensed ring groups such as naphthalene ring (10 carbon atoms ring) and anthracene ring (14 carbon atoms ring) are the total molecular weight of the carbon atoms constituting the condensed ring (i.e., 120 and 168 ). When the aromatic ring is a heteroaromatic ring, the molecular weight of the aromatic ring structure is based on the weights of heteroatoms and carbon atoms forming the heteroaromatic ring. The aromatic ring group that constitutes the oligomer A preferably does not contain a heteroatom.

<<<Embodiment of Preferred Raw Material Epoxy Resin>>>
As such a raw material epoxy resin, an epoxy resin represented by the following formula (1) is preferable.

[In the formula,
G ¹ and G ² are independently a glycidyl group or a methylglycidyl group;
R ¹¹ is a hydrogen atom or a methyl group,
X ¹ is an optionally substituted aryl-O- group having 6 to 20 carbon atoms, an optionally substituted aryl-(OR ¹ ) _n1 -O- group having 6 to 20 carbon atoms ( wherein R ¹ is an alkylene having 1 to 6 carbon atoms and n1 is an integer of 1 to 10), or an optionally substituted heteroaryl group having a total number of atoms of 5 to 30 ,
Y ¹ is an arylene group having 6 to 20 carbon atoms, alkylene having 1 to 4 carbon atoms-arylene group having 6 to 20 carbon atoms, or alkylene having 1 to 4 carbon atoms-arylene having 6 to 20 carbon atoms. - alkylene group having 1 to 4 carbon atoms, arylene group having 6 to 20 carbon atoms - alkylene group having 1 to 4 carbon atoms - arylene group or group having 6 to 20 carbon atoms: -R ² -(OR ² ) _n2 — (wherein R ² is an alkylene group having 1 to 6 carbon atoms and n2 is 0 or an integer of 1 to 6), but
provided that the number of benzene rings in the molecule is 3 or more]

In formula (1), G ¹ and G ² are independently a glycidyl group or a methylglycidyl group. From the viewpoint of ease of synthesis, G ¹ and G ² are preferably the same and a glycidyl group.

In formula (1), R ¹¹ is a hydrogen atom or a methyl group. From the viewpoint of ease of synthesis, R ¹¹ is preferably a hydrogen atom.

In formula (1), X ¹ is an optionally substituted aryl-O- group having 6 to 20 carbon atoms, or an optionally substituted aryl-(OR ¹ ) having 6 to 20 carbon atoms. _n1 -O- group (wherein R ¹ is an alkylene group having 1 to 6 carbon atoms and n1 is an integer of 1 to 10), or a total number of atoms that may be substituted 5 to 30 heteroaryl groups.

The aryl group having 6 to 20 carbon atoms is a monocyclic or polycyclic aromatic hydrocarbon group, and includes a phenyl group, a biphenylyl group, a naphthyl group, a terphenylyl group, an anthracenyl group, a fluorenyl group and the like. A biphenylyl group is preferred.

Substituents of the aryl group having 6 to 20 carbon atoms are not particularly limited, and examples thereof include alkyl groups, alkoxy groups, alkylcarbonyl groups, alkylmercapto groups and cycloalkyl groups having 1 to 4 carbon atoms.

Examples of the alkyl group having 1 to 4 carbon atoms include methyl group, ethyl group, propyl group, i-propyl group, butyl group, i-butyl group, sec-butyl group and tert-butyl group.

Examples of the alkyl moiety in the alkoxy group include the aforementioned alkyl groups having 1 to 4 carbon atoms. Alkoxy groups include methoxy, ethoxy, propoxy, butoxy, i-butoxy, sec-butoxy and tert-butoxy groups. Examples of the alkyl group in the alkylcarbonyl group and the alkylmercapto group include the aforementioned alkyl groups having 1 to 4 carbon atoms. The alkylcarbonyl group includes acetyl group, propanoyl group, 2-methylpropanoyl group, butanoyl group and the like. The alkylmercapto group includes methylmercapto group, ethylmercapto group, propylmercapto group, i-propylmercapto group, butylmercapto group, i-butylmercapto group, sec-butylmercapto group, tert-butylmercapto group and the like. The cycloalkyl group is a monocyclic or polycyclic aliphatic hydrocarbon group having 3 to 20 carbon atoms, and includes cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, A cyclododecyl group, an adamantyl group, and the like can be mentioned.

Alkylene groups having 1 to 4 carbon atoms are methylene group, ethylene group, trimethylene group, propylene group (propane-1,2-diyl group), propylidene group (propane-1,1-diyl group), isopropylidene group ( propane-2,2-diyl group), tetramethylene group, butylidene group (butane-1,1-diyl group), isobutylidene group (2-methylpropane-1,1-diyl group) and the like. In addition, the alkylene group having 1 to 6 carbon atoms is, in addition to the above alkylene group having 1 to 4 carbon atoms, carbon atoms such as pentamethylene group, 2-methylpentane-1,5-diyl group and hexamethylene group. Alkylene groups having 5 and 6 atoms are included.

A heteroaryl group having a total number of atoms of 5 to 30 is a monocyclic or polycyclic heterocyclic group containing, in addition to carbon atoms, at least one heteroatom selected from the group consisting of at least an oxygen atom, a sulfur atom and a nitrogen atom. , phthalimidyl group, imidazolyl group, xanthenyl group, thioxanthenyl group, thienyl group, dibenzofuryl group, chromenyl group, isothiochromenyl group, phenoxathiinyl group, pyrrolyl group, pyrazolyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group , indolizinyl group, isoindolyl group, indolyl group, indazolyl group, purinyl group, quinolidinyl group, isoquinolyl group, quinolyl group, phthalazinyl group, naphthyridinyl group, quinoxalinyl group, quinazolinyl group, cinnolinyl group, pteridinyl group, carbazolyl group, β-carbolinyl group , phenanthridinyl group, acridinyl group, perimidinyl group, phenanthrolinyl group, phenazinyl group, isothiazolyl group, phenothiazinyl group, isoxazolyl group, furazanyl group and the like. Substituents for the heteroaryl group having a total number of atoms of 5 to 30 include the aforementioned substituents for the aryl group having 6 to 20 carbon atoms.

X ¹ is a phenoxy group, 4-tert-butyl-phenoxy group, biphenyl-2-yloxy group, phthalimidyl group, phenyl-(OCH ₂ CH ₂ ) _n1a -O- group (wherein n1a is an integer of 2 to 10 is preferred, and a phenoxy group is more preferred.

In formula (1), Y ¹ is an arylene group having 6 to 20 carbon atoms, an alkylene group having 1 to 4 carbon atoms-an arylene group having 6 to 20 carbon atoms, or an alkylene group having 1 to 4 carbon atoms. arylene having 6 to 20 carbon atoms - alkylene group having 1 to 4 carbon atoms, arylene having 6 to 20 carbon atoms - alkylene having 1 to 4 carbon atoms - arylene group or group having 6 to 20 carbon atoms: -R ² —(OR ² ) _n2 — (wherein R ² is an alkylene group having 1 to 6 carbon atoms and n2 is 0 or an integer of 1 to 6).

The arylene group having 6 to 20 carbon atoms is a monocyclic or polycyclic aromatic group and includes a phenylene group, a naphthylene group and an anthracenylene group, preferably a phenylene group.

Examples of the alkylene group having 1 to 4 carbon atoms and the arylene group having 6 to 20 carbon atoms in the alkylene group having 1 to 4 carbon atoms and the arylene group having 6 to 20 carbon atoms are as described above. As the alkylene group having 1 to 4 carbon atoms and the arylene group having 6 to 20 carbon atoms, an ethylene-1,4-phenylene group is preferred. The order of bonding to each group in the alkylene group having 1 to 4 carbon atoms and the arylene group having 6 to 20 carbon atoms may be any, but the oxygen atom to which the group containing X ¹ is bonded may be a carbon atom The arylene group having 6 to 20 carbon atoms in the alkylene group having 1 to 4 carbon atoms and the arylene group having 6 to 20 carbon atoms is preferably bonded.

Examples of the alkylene group having 1 to 4 carbon atoms and the arylene group having 6 to 20 carbon atoms in the alkylene group having 1 to 4 carbon atoms - the arylene group having 6 to 20 carbon atoms - the alkylene group having 1 to 4 carbon atoms are , as described above. 1,3-phenylenebismethylene group (m-xylylene group) and 1,4-phenylenebismethylene group as the alkylene group having 1 to 4 carbon atoms - arylene group having 6 to 20 carbon atoms - alkylene group having 1 to 4 carbon atoms A methylene group (p-xylylene group) is preferred.

（式中、Ｒ^２１及びＲ^２２は、互いに独立して、水素原子、メチル基、エチル基、トリフルオロメチル基又はフェニル基である）が好ましく、

が特に好ましい。Examples of the arylene group having 1 to 4 carbon atoms and the arylene group having 6 to 20 carbon atoms in the arylene group having 6 to 20 carbon atoms-alkylene having 1 to 4 carbon atoms-arylene group having 6 to 20 carbon atoms are , as described above. The following group as the arylene group having 6 to 20 carbon atoms-alkylene group having 1 to 4 carbon atoms-arylene group having 6 to 20 carbon atoms:

(wherein R ²¹ and R ²² are each independently a hydrogen atom, a methyl group, an ethyl group, a trifluoromethyl group or a phenyl group) are preferably

is particularly preferred.

In formula (1), Y ¹ is an arylene group having 6 to 20 carbon atoms, an alkylene group having 1 to 4 carbon atoms-an arylene group having 6 to 20 carbon atoms, or an alkylene group having 1 to 4 carbon atoms. Arylene having 6 to 20 carbon atoms - alkylene group having 1 to 4 carbon atoms, or arylene having 6 to 20 carbon atoms - alkylene having 1 to 4 carbon atoms - arylene group having 6 to 20 carbon atoms preferable. In preferred epoxy compounds having Y ¹ , both X ¹ and Y ¹ have an aromatic ring. When an epoxy compound in which both X ¹ and Y ¹ have an aromatic ring is used, the obtained cured product is more excellent in low moisture permeability.

In formula (1), the total number of benzene rings possessed by X ¹ and Y ¹ is 3 or more. Using an epoxy resin in which the total number of benzene rings possessed by X ¹ and Y ¹ is 2 does not result in an epoxy resin with an epoxy equivalent of 200 g/epo or more and an aromatic ring weight of 0.43 or more. In some cases, the adhesion to the alignment layer may be poor and/or the moisture permeability may be high.

Such a compound obtained by partially (meth)acrylic modifying the epoxy resin represented by formula (1) is such that part of G ¹ and/or G ² in the epoxy resin represented by formula (1) is a group:- CH ₂ CR ¹³ (OR ³¹ )CH ₂ OZ (wherein R ¹³ is a hydrogen atom or a methyl group, R ³¹ is a hydrogen atom or a (meth)acryloyl group, Z is a (meth) is an acryloyl group).

The epoxy compound represented by the above formula (1) and the compound obtained by partially (meth)acrylic modifying the epoxy compound represented by the above formula (1) can be produced by the method described in JP-A-2017-002246.

<<Preferred Embodiment of Oligomer A>>
From the viewpoint of low moisture permeability, the oligomer A preferably has 3 or more benzene rings in one molecule, more preferably 3 to 6 benzene rings in one molecule, and 4 benzene rings in one molecule. It is particularly preferred to have ~6. Here, the group having a condensed ring refers to the number of benzene rings in a single ring constituting the condensed ring. For example, a naphthalene ring has two benzene rings, and a pyrene ring has four benzene rings. When the oligomer A has three or more benzene rings in one molecule, the benzene rings preferably exist independently (that is, contain no condensed rings).

で表される構造である。このような特に好ましい化合物としてビスフェノールＦ型の構造の他に、フェニル基を１つ有する化合物が挙げられる。In addition, from the viewpoint of low moisture permeability, the oligomer A preferably has a bisphenol F type structure, and particularly preferably has three or more benzene rings in one molecule and has a bisphenol F type structure. . Here, the structure of bisphenol F type is as follows:

It is a structure represented by Examples of such particularly preferred compounds include compounds having one phenyl group in addition to the bisphenol F type structure.

Oligomer A may be one or a combination of two or more. Oligomer A is not a component corresponding to oligomer B described later. That is, the oligomer A is a compound obtained by partially (meth)acrylic modifying a bisphenol A type epoxy resin, a compound obtained by partially (meth)acrylic modifying a bisphenol F type epoxy resin, and a compound obtained by partially (meth)acrylic modifying a bisphenol AD type epoxy resin. isn't it.

<Oligomer B>
Oligomer B is a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol AD type epoxy resin, and partially (meth)acrylic modified compounds thereof (that is, a compound obtained by partially (meth)acrylic modifying a bisphenol A type epoxy resin, bisphenol It is one or more selected from the group consisting of compounds obtained by partially (meth)acryl-modified F-type epoxy resins and compounds obtained by partially (meth)acryl-modified bisphenol AD-type epoxy resins. Here, the bisphenol A type epoxy resin is an epoxy resin which is a condensation product of bisphenol A (2,2-bis(4-hydroxyphenyl)propane) and epichlorohydrin. Bisphenol F type epoxy resin is an epoxy resin which is a condensation product of bisphenol F (bis(4-hydroxyphenyl)methane) and epichlorohydrin. A bisphenol AD type epoxy resin is an epoxy resin which is a condensation product of bisphenol AD (1,1-bis(4-hydroxyphenyl)ethane) and epichlorohydrin.

From the viewpoint of adhesion to the alignment film, oligomer B is preferably one or more selected from the group consisting of bisphenol F-type epoxy resins and compounds obtained by partially (meth)acrylic modifying bisphenol F-type epoxy resins.
Oligomer B may be one or a combination of two or more.

<Other curable resins>
The curable resin other than oligomer A and oligomer B (hereinafter also referred to as "oligomer C") is not particularly limited, and conventional ethylenically unsaturated groups and/or A resin having an epoxy group can be mentioned.

Oligomer C, which is a resin having an epoxy group, is not particularly limited as long as it has one or more epoxy groups. Examples of resins having such an epoxy group include raw material epoxy resins and epoxy resins other than raw material epoxy resins. Here, the "epoxy resin other than the raw material epoxy resin" is an epoxy resin having an epoxy equivalent weight of 200 g/epo or more and an aromatic ring weight of less than 0.43; an epoxy equivalent weight of less than 200 g/epo, and , an epoxy resin having an aromatic ring weight of 0.43 or more; or an epoxy resin having an epoxy equivalent weight of less than 200 g/epo and an aromatic ring weight of less than 0.43. Oligomer C, which is a resin having an epoxy group, is an epoxy obtained by adding an alkylene carbonate or haloalcohol to a compound having one or more phenolic hydroxyl groups and further glycidyl etherifying, as described in JP-A-2017-214462. Resins are preferred.

Examples of the oligomer C, which is a resin having an ethylenically unsaturated group, include compounds in which all the epoxy groups of the oligomer C, which is a resin having an epoxy group, are (meth)acryl-modified.

Examples of the oligomer C, which is a resin having an ethylenically unsaturated group and an epoxy group, include partially (meth)acryl-modified compounds of epoxy resins other than the raw material epoxy resin.

Oligomer C is described in WO2014/057871, JP-A-2017-002204, etc., in addition to those described above, and can be selected as appropriate. In addition, it is preferable that the oligomer C does not have a silicon atom.

(photoinitiator)
A photoinitiator means a compound that is activated by absorbing light energy and generates radicals. Photopolymerization initiators are not particularly limited, and include benzoins, acetophenones, benzophenones, thioxatones, α-acyloxime esters, phenylglyoxylates, benzils, azo compounds, diphenylsulfide compounds, acylphosphines. Polymerization initiators such as oxide compounds, benzoins, benzoin ethers and anthraquinones can be mentioned. The photopolymerization initiator preferably has a low solubility in liquid crystals and has a reactive group that itself does not gasify decomposition products upon irradiation with light. Examples of such a preferable polymerization initiator include EY Resin KR-2 (manufactured by KSM Co., Ltd.). Further, as a radical polymerization initiator, a compound obtained by reacting a compound having at least two epoxy groups and dimethylaminobenzoic acid, which is described in WO2012/077720, and at least two epoxy groups. A polymerization initiator that is a mixture of a compound obtained by reacting a compound having a hydroxythioxanthone with hydroxythioxanthone is preferred.

(Heat curing agent)
The heat curing agent is not particularly limited, but includes amine-based curing agents such as organic acid dihydrazide compounds, amine adducts, imidazole and its derivatives, dicyandiamide, aromatic amines, epoxy-modified polyamines, and polyaminourea. ,3-bis(hydrazinocarboethyl)-5-isopropylhydantoin), ADH (adipic dihydrazide), UDH (7,11-octadecane-1,18-dicarbohydrazide) and LDH (octadecane-1,18 - organic acid dihydrazides such as dicarboxylic acid dihydrazide); ADEKA Co., Ltd., ADEKA HARDNER EH5030S, Ajinomoto Fine-Techno Co., Ltd., Amicure PN-23, Amicure PN-30, Amicure MY-24, Amicure MY-H, etc. Amine adducts are preferred. These curing agents may be used alone or in combination.

(additional ingredients)
The liquid crystal dropping method sealant can further contain additional components such as fillers and coupling agents. Each additional ingredient may be used alone or in combination of two or more.

The filler controls the viscosity of the liquid crystal dripping method sealant, improves the strength of the cured product obtained by curing the liquid crystal dripping method sealant, or improves the adhesion reliability of the liquid crystal dripping method sealant by suppressing linear expansion. It is added for purposes such as The filler is not particularly limited, and examples thereof include known inorganic fillers and organic fillers used for sealant for liquid crystal dripping method.

Inorganic fillers include calcium carbonate, magnesium carbonate, barium sulfate, magnesium sulfate, aluminum silicate, titanium oxide, alumina, zinc oxide, silicon dioxide, kaolin, talc, glass beads, sericite activated clay, bentonite, aluminum nitride, and nitride. silicon.

Examples of organic fillers include polymethyl methacrylate, polystyrene, copolymers obtained by copolymerizing the monomers constituting these with other monomers, polyester fine particles, polyurethane fine particles, rubber fine particles, and copolymers having a high glass transition temperature. Examples include core-shell type particles composed of a shell containing a polymer and a core of a copolymer having a low glass transition temperature.

A commercial item can be used for the filler. Commercially available inorganic fillers include glass filler (“CF0023-05C” manufactured by Nippon Frit Co., Ltd.), amorphous silica (“Seahoster KE-P250” manufactured by Nippon Shokubai Co., Ltd.), fumed silica (thixotropic agent) (Cabot Specialty) "TG-308F" manufactured by Chemicals Co., Ltd.), spherical silica ("CF0018-WB15C" manufactured by Nihon Frit Co., Ltd.), silica particles (Seahoster KE series (KE-C50, etc.)), and the like. In addition, commercially available organic fillers include Zefiac series (F-351, etc., manufactured by Aica Kogyo Co., Ltd.) as core-shell type particles.
Each filler may be one or a combination of two or more.

A coupling agent is added for the purpose of further improving the adhesiveness to the liquid crystal display substrate. The coupling agent is not particularly limited and includes γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-isocyanatopropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane and 3-glycidoxysilane. propyltrimethoxysilane and the like. The silane coupling agent may be one or a combination of two or more.

Further components other than the filler and the coupling agent include known components and commercial products as additives added to the sealing agent for the liquid crystal dropping method.

(composition)
The content of oligomer A is preferably 1 to 99 parts by weight, more preferably 10 to 95 parts by weight, and more preferably 40 to 90 parts by weight with respect to a total of 100 parts by weight of oligomer A and oligomer B. It is particularly preferred to have

The content of the oligomer A is preferably 1 to 100 parts by weight, more preferably 50 to 99 parts by weight, and 90 to 95 parts by weight with respect to the total 100 parts by weight of the oligomer A. is particularly preferred.

The content of the oligomer B is preferably 1 to 100 parts by weight, more preferably 50 to 99 parts by weight, and 90 to 95 parts by weight with respect to the total 100 parts by weight of the oligomer B. is particularly preferred.

The total content of oligomer A and oligomer B is preferably 50 to 100 parts by weight, particularly preferably 70 to 100 parts by weight, with respect to 100 parts by weight of the total curable resin. In addition, in the curable resin, the oligomer C is the component other than the oligomer A and the oligomer B.

The content of the photopolymerization initiator is preferably 0.1 to 10 parts by weight, more preferably 1 to 5 parts by weight, with respect to 100 parts by weight of the total curable resin.

The content of the thermosetting agent is preferably 1 to 50 parts by weight, more preferably 5 to 40 parts by weight, with respect to 100 parts by weight of the total curable resin.

The content of the filler is preferably 1 to 50 parts by weight, more preferably 5 to 30 parts by weight, with respect to the total 100 parts by weight of the curable resin.

The content of the coupling agent is preferably 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, with respect to 100 parts by weight of the total curable resin.

The content of the curable resin is preferably 40 parts by weight or more and less than 100 parts by weight, and more preferably 60 parts by weight or more and less than 100 parts by weight, based on a total of 100 parts by weight of the sealant for the liquid crystal dropping method. .

(Application)
A cured product of the sealant for the liquid crystal dropping method is used for sealing the liquid crystal display. The liquid crystal display is not particularly limited, and a liquid crystal display to which a conventional liquid crystal dropping method sealant is applied can be used. The sealant for the liquid crystal dropping method can be cured by applying heat by irradiation with energy rays such as ultraviolet rays, or by applying heat before, after, or simultaneously with irradiation with energy rays such as ultraviolet rays.

Specific embodiments of the present invention will now be described in more detail with reference to examples, but the present invention is not limited to these examples.

(product used)
Components used in Examples and Comparative Examples are as follows. The sealants for the liquid crystal dripping method of Examples and Comparative Examples were prepared by mixing the following components so as to have the compositions described in the table. In addition, the value in a table|surface is a weight part.

化合物１は以下の方法で得た。1. Oligomer A
(1) Compound 1

Compound 1 was obtained by the following method.

(Production of compound 1)
Phenyl glycidyl ether (EX-141, manufactured by Nagase ChemteX Corporation) 166 g, Resitop BPF-SG (bisphenol F) (manufactured by Gunei Chemical Industry Co., Ltd.) 200 g, benzyltrimethylammonium chloride (manufactured by Tokyo Kasei Co., Ltd.) 10 g, toluene (Kanto Chemical Co., Ltd.) was placed in a flask equipped with a thermometer and a stirrer, and stirred at 120° C. for 8 hours. After completion of the reaction, the mixture was cooled to room temperature and washed once with 2000 g of a 1% aqueous sodium hydroxide solution and twice with 2000 mL of water. The solvent in the resulting organic phase was removed by distillation under reduced pressure to obtain 336 g of a yellow transparent viscous ring-opened compound (EX-141-bisphenol F ring-opened compound).

330 g of EX-141-bisphenol F ring-opening compound, 1742 g of epichlorohydrin (manufactured by Wako Pure Chemical Industries, Ltd.), and 35 g of benzyltrimethylammonium chloride (manufactured by Tokyo Kasei Co., Ltd.) were added to a thermometer, a condenser, a Dean-Stark trap, and a dropping funnel. , was placed in a 2 L three-necked round bottom flask equipped with a stirrer. The mixture was then heated to about 50° C. with stirring under a vacuum of 50 torr, and 282 g of 48% aqueous sodium hydroxide solution (manufactured by Kanto Kagaku Co., Ltd.) was added dropwise over 3 hours. Stirring was continued while returning epichlorohydrin from the azeotropically distilled water/epichlorohydrin mixture to the reaction system. Stirring was continued for 3 hours after the addition was complete. Then, the reaction mixture was cooled to room temperature, added with 900 g of toluene and 300 g of methyl isobutyl ketone, and washed four times with 1500 mL of water. The solvent in the resulting organic phase was removed by distillation under reduced pressure to obtain 395 g of a yellow transparent viscous glycidyl ether (compound 1a, raw material epoxy resin).

200 g of compound 1a, 35 g of methacrylic acid (manufactured by Tokyo Kasei Co., Ltd.), 212 mg of triphenylphosphine (manufactured by Tokyo Kasei Co., Ltd.) as a catalyst, and 50 mg of BHT (dibutylhydroxytoluene, manufactured by Kanto Kagaku Co., Ltd.) are placed in a flask equipped with a thermometer and a stirrer. and stirred at 100° C. for 8 hours. After completion of the reaction, a partially methacrylated epoxy compound (compound 1) was obtained.

化合物２は、特開２０１７－００２２４６号公報の第１０６段落～第１１１段落に記載の方法に従って得た。(2) Compound 2

Compound 2 was obtained according to the method described in paragraphs 106 to 111 of JP-A-2017-002246.

化合物３は以下の方法で得た。(3) Compound 3

Compound 3 was obtained by the following method.

(Production of compound 3)
Phenyl glycidyl ether (EX-141, manufactured by Nagase ChemteX Corporation) 50 g, BisP-AP (manufactured by Honshu Chemical Industry Co., Ltd.) 116 g, benzyltrimethylammonium chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) 3.1 g, toluene (manufactured by Kanto Chemical Co., Ltd.) 200 g was placed in a flask equipped with a thermometer and a stirrer, and stirred at 120°C for 8 hours. After completion of the reaction, the mixture was cooled to room temperature, 200 g of methyl isobutyl ketone (manufactured by Kanto Kagaku Co., Ltd.) was added, and the mixture was washed with 500 g of a 1% aqueous sodium hydroxide solution four times and with 500 mL of water four times. The solvent in the obtained organic phase was removed by distillation under reduced pressure to obtain 124 g of a yellow transparent viscous ring-opened compound (EX-141-BisP-AP ring-opened compound).

100 g of EX-141-BisP-AP ring-opened product, 421 g of epichlorohydrin (manufactured by Wako Pure Chemical Industries, Ltd.), and 8.4 g of benzyltrimethylammonium chloride (manufactured by Tokyo Kasei Co., Ltd.) were added to a thermometer, a condenser, and a Dean-Stark trap. , addition funnel, and a 1 L three-necked round-bottomed flask equipped with a stirrer. The mixture was then heated to about 50° C. with stirring under a vacuum of 50 torr, and 68 g of 48% aqueous sodium hydroxide solution (manufactured by Kanto Kagaku Co., Ltd.) was added dropwise over 3 hours. Stirring was continued while returning epichlorohydrin from the azeotropically distilled water/epichlorohydrin mixture to the reaction system. Stirring was continued for 3 hours after the addition was complete. Then, the reaction mixture was cooled to room temperature, added with 250 g of toluene and 250 g of methyl isobutyl ketone, and washed four times with 500 mL of water. The solvent in the resulting organic phase was removed by distillation under reduced pressure to obtain 120 g of a yellow transparent viscous glycidyl ether (compound 3a, raw material epoxy resin).

50 g of compound 3a, 7.2 g of methacrylic acid (manufactured by Tokyo Kasei Co., Ltd.), 22 mg of triphenylphosphine (manufactured by Tokyo Kasei Co., Ltd.) as a catalyst, and 11 mg of BHT (dibutylhydroxytoluene, manufactured by Kanto Kagaku Co., Ltd.) were added with a thermometer and a stirrer. The mixture was placed in a flask and stirred at 100° C. for 8 hours. After completion of the reaction, a partially methacrylated epoxy compound (compound 3) was obtained.

化合物４は以下の方法で得た。(4) Compound 4

Compound 4 was obtained by the following method.

(Production of compound 4)
Biphenyl-type monofunctional epoxy resin (OPP-G, manufactured by Sanko) 75 g, 2,2-bis(4-hydroxyphenyl)propane (bisphenol A) (manufactured by Kanto Chemical Co., Ltd.) 91 g, benzyltrimethylammonium chloride (manufactured by Tokyo Kasei Co., Ltd.) ) and 200 g of toluene (manufactured by Kanto Kagaku Co., Ltd.) were placed in a flask equipped with a thermometer and a stirrer, and stirred at 120° C. for 8 hours. After completion of the reaction, the mixture was cooled to room temperature, 200 g of methyl isobutyl ketone (manufactured by Kanto Chemical Co., Ltd.) was added, and the mixture was washed twice with 1000 g of 1% aqueous sodium hydroxide solution and twice with 1000 mL of water. The solvent in the obtained organic phase was removed by distillation under reduced pressure to obtain 135 g of a yellow transparent viscous ring-opened compound (OPP-G-bisphenol A ring-opened compound).

100 g of OPP-G-bisphenol A ring-opening compound, 406 g of epichlorohydrin (manufactured by Wako Pure Chemical Industries, Ltd.), 8.2 g of benzyltrimethylammonium chloride (manufactured by Tokyo Kasei Co., Ltd.) were added to a thermometer, a cooling tube, a Dean-Stark trap, Place in a 1 L 3-necked round-bottomed flask equipped with a dropping funnel and stirrer. The mixture was then heated to about 50° C. with stirring under a vacuum of 50 torr, and 66 g of 48% aqueous sodium hydroxide solution (manufactured by Kanto Kagaku Co., Ltd.) was added dropwise over 3 hours. Stirring was continued while returning epichlorohydrin from the azeotropically distilled water/epichlorohydrin mixture to the reaction system. Stirring was continued for 3 hours after the addition was complete. Then, the reaction mixture was cooled to room temperature, added with 250 g of toluene and 250 g of methyl isobutyl ketone, and washed four times with 500 mL of water. The solvent in the resulting organic phase was removed by distillation under reduced pressure to obtain 113 g of a yellow transparent viscous glycidyl ether (compound 4a, raw material epoxy resin).

50 g of compound 4a, 7.0 g of methacrylic acid (manufactured by Tokyo Kasei Co., Ltd.), 21 mg of triphenylphosphine (manufactured by Tokyo Kasei Co., Ltd.) as a catalyst, and 11 mg of BHT (dibutylhydroxytoluene, manufactured by Kanto Kagaku Co., Ltd.) were added with a thermometer and a stirrer. The mixture was placed in a flask and stirred at 100° C. for 8 hours. After completion of the reaction, a partially methacrylated epoxy compound (compound 4) was obtained.

化合物５は以下の方法で得た。2. Oligomer B
(1) Compound 5

Compound 5 was obtained by the following method.

(Production of compound 5)
200 g of bisphenol F type epoxy resin (EXA-830CRP, manufactured by DIC), 54 g of methacrylic acid (manufactured by Tokyo Kasei Co., Ltd.), 328 mg of triphenylphosphine as a catalyst (manufactured by Tokyo Kasei Co., Ltd.), BHT (dibutylhydroxytoluene, Kanto Chemical Co., Ltd.) 50 mg of the product) was placed in a flask equipped with a thermometer and a stirrer, and stirred at 100° C. for 8 hours. After completion of the reaction, a partially methacrylated epoxy compound (compound 5) was obtained.

化合物６は、ＷＯ２０１４／０５７８７１の第９２段落に記載された方法に従って得た。(2) Compound 6

Compound 6 was obtained according to the method described in paragraph 92 of WO2014/057871.

化合物７は、特開２０１７－２１４４６２号公報の第１３１段落～第１３５段落に記載の方法に従って得た。3. Oligomer C
(1) Compound 7

Compound 7 was obtained according to the method described in paragraphs 131 to 135 of JP-A-2017-214462.

光開始剤１は、ＷＯ２０１２／０７７７２０の第５８段落に記載された方法に従って得た。4. Photoinitiator (1) Photoinitiator 1

Photoinitiator 1 was obtained according to the method described in paragraph 58 of WO2012/077720.

光開始剤２は、ＷＯ２０１２／０７７７２０の第６０段落に記載された方法に従って得た。(2) Photoinitiator 2

Photoinitiator 2 was obtained according to the method described in paragraph 60 of WO2012/077720.

5. Heat curing agent polyamine compound (EH-5030S, manufactured by ADEKA, active hydrogen equivalent 105 g / eq)

6. Other components (1) Filler/organic filler; core-shell type particles (Zefiac F-351, manufactured by Aica Kogyo Co., Ltd.)
Inorganic filler; silicon dioxide particles (Seahoster KE-C50, manufactured by Nippon Shokubai Co., Ltd.)
Inorganic filler; fumed silica (thixotropic agent) (TG-308F, manufactured by Cabot Specialty Chemicals)
(2) Coupling agent/silane coupling agent; 3-glycidoxypropylmethyldiethoxysilane (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.)

(Measurement of epoxy equivalent)
The epoxy equivalents of the epoxy resins (raw material epoxy resins) before methacrylic acid modification of compounds 1 to 7 were measured according to JIS K7236:2001.

(Aromatic ring amount)
The aromatic ring content of the epoxy resin before methacrylic acid modification of compounds 1 to 7 was calculated based on the structural formula of the corresponding starting epoxy resin.

(adhesion strength)
Polyimide-based alignment liquid (Sunever SE-7492, manufactured by Nissan Chemical Industries, Ltd.) was dropped (0.4 MPa, 5.0) using an air dispenser onto an ITO substrate (403005XG-10SQ1500A, manufactured by Geomatec) that had been washed with pure water and dried. After that, the spin coater reached 5000 rpm in 10 seconds and was then kept for 20 seconds for uniform coating. After uniform application, pre-baking (1 minute) on a hot plate at 85° C. and post-baking (60 minutes) in an oven at 230° C. produced a substrate with a polyimide alignment film.

A sealant for the liquid crystal dropping method was applied to the positions of 15 mm × 3 mm and 15 mm × 21 mm on the ITO substrate with 6 μm spacers and the substrate with polyimide alignment film (30 mm × 30 mm × 0.5 mmt). The diameter of the sealing agent for the substrate was in the range of 1.5 to 2.5 mm. After that, the same type of substrate (23 mm × 23 mm × 0.5 mmt) is bonded together and irradiated with ultraviolet light at an integrated light amount of 3,000 mJ/cm ² (irradiation device: UVX-01224S1, manufactured by Ushio Inc.) to cure at 120 ° C. Heat curing was performed in an oven for 1 hour to prepare a test piece. Using an autograph (TG-2kN, manufactured by Minebea Co., Ltd.), the test piece is fixed and the position of 15 mm × 25 mm of the substrate is punched out at a speed of 5 mm / min, ITO substrates (ITO / ITO) and polyimide substrates ( The adhesive strength of PI/PI(TN)) was measured.

(moisture permeability)
A sealant for the liquid crystal dropping method is sandwiched between PET films of 100 mm × 100 mm and a thickness of 0.1 mm so that the diameter is 3.6 mm to 3.8 mm and the thickness is 0.28 mm to 0.32 mm, and UV irradiation is performed at 100 mW/cm ² . Both surfaces were irradiated with light energy of 1,500 mJ/cm ² at an illuminance, and heat curing was performed in a hot air oven at 120° C. for 1 hour to obtain a sample for moisture permeability measurement. Moisture permeability was measured according to JISK0208:1976, using a constant temperature and humidity chamber of 65°C/95%, and calculating the moisture permeability from the weight change by the moisture permeable cup method. The unit of moisture permeability is g/(m ² ·24h).

(Seal pass test in liquid crystal test cell)
On an ITO glass substrate (thickness 0.7 mm) with an alignment film (SE-5662, manufactured by Nissan Chemical Industries, Ltd.), a sealant for the liquid crystal dropping method is applied using a seal dispenser to a frame shape of 25 mm × 25 mm. A pattern was applied by dispensing. After that, liquid crystal (MLC-6609, manufactured by Merck Co., Ltd.) is dropped onto the substrate by the liquid crystal dropping method, and the upper and lower substrates are bonded together. : 3,000 mJ/cm ² ) for photocuring, and then heat curing for 60 minutes in a hot air oven at 120°C to prepare a test cell.
Regarding the prepared liquid crystal test cells, those with seal paths were evaluated as x, and those with no seal paths were evaluated as ○.

The results are summarized in Tables 1 and 2.

The sealant for the liquid crystal dropping method of the example gave a cured product having excellent adhesiveness to the alignment film and excellent low moisture permeability. Further, in the seal pass test, no seal pass was observed with the sealant for the liquid crystal dripping method of the example, and the liquid crystal could be sealed.
By comparing Examples 1 and 2, when the oligomer B had a bisphenol F type structure, it was excellent in low moisture permeability.
By comparing Examples 1 and 3, when the oligomer A had a bisphenol F type structure, it was excellent in low moisture permeability.
By comparing Examples 1 and 4, when the content of oligomer A is small with respect to a total of 100 parts by weight of oligomer A and oligomer B, low moisture permeability is excellent.
By comparing Examples 4 to 6, when the epoxy equivalent weight and the aromatic ring weight of the raw material epoxy resin of oligomer A were within the more preferable ranges, low moisture permeability was excellent. In particular, by comparing Examples 5 and 6, when the epoxy equivalent of the raw material epoxy resin of the oligomer A was large, the low moisture permeability was excellent.

On the other hand, since the sealant for the liquid crystal dropping method of Comparative Example 1 contained only the oligomer A, the cured product obtained using the sealant for the liquid crystal dropping method of Comparative Example 1 had high moisture permeability.
Since the sealant for liquid crystal dropping method of Comparative Example 2 contains only oligomer B, the sealant for liquid crystal dropping method of Comparative Example 2 is inferior in adhesion to the alignment film, and the sealant for liquid crystal dropping method of Comparative Example 2 is inferior in adhesion to the alignment film. The cured product obtained using the agent had high moisture permeability.
The sealant for liquid crystal dripping method of Comparative Example 3 contains two kinds of oligomers B. In addition, the sealant for the liquid crystal dripping method of Comparative Example 3 is compound 5, which is "an oligomer having an epoxy equivalent of less than 200 g/epo and an aromatic ring content of 0.43 or more" instead of oligomer A. Therefore, the sealing compound for liquid crystal dropping method of Comparative Example 3 has poor adhesion to the alignment film, and the cured product obtained using the sealing compound for liquid crystal dropping method of Comparative Example 3 has high moisture permeability. rice field.
The sealant for liquid crystal dropping method of Comparative Example 4 contains compound 7, which is "an oligomer having an epoxy equivalent of 200 g/epo or more and an aromatic ring weight of less than 0.43" instead of oligomer A. Therefore, the cured product obtained by using the sealant for liquid crystal dripping method of Comparative Example 4 had high moisture permeability.

Claims (3)

A sealant for a liquid crystal dropping method, comprising a curable resin, a photoinitiator and a thermosetting agent,
the curable resin comprises an oligomer A and an oligomer B;
Oligomer A is a compound obtained by partially (meth)acrylic modifying an epoxy resin having an epoxy equivalent of 200 g/epo or more and an aromatic ring weight of 0.43 or more, and having a bisphenol F type structure. or
Oligomer A has an epoxy equivalent of 200 g/epo or more and an aromatic ring weight of 0.43 or more, represented by the following formula (1):

[In the formula,
G ¹ and G ² are independently a glycidyl group or a methylglycidyl group;
R ¹¹ is a hydrogen atom or a methyl group,
X ¹ is an optionally substituted aryl-O- group having 6 to 20 carbon atoms, an optionally substituted aryl-(OR 1 ) n1 -O- group having 6 to ²⁰ carbon _atoms ( wherein R ¹ is an alkylene having 1 to 6 carbon atoms and n1 is an integer of 1 to 10), or an optionally substituted heteroaryl group having a total number of atoms of 5 to 30 ,
Y ¹ is an arylene group having 6 to 20 carbon atoms, alkylene having 1 to 4 carbon atoms-arylene group having 6 to 20 carbon atoms, alkylene having 1 to 4 carbon atoms-arylene having 6 to 20 carbon atoms - alkylene group having 1 to 4 carbon atoms, arylene group having 6 to 20 carbon atoms - alkylene group having 1 to 4 carbon atoms - arylene group or group having 6 to 20 carbon atoms: -R 2 - ⁽ OR ² ) _n2 — (wherein R ² is an alkylene group having 1 to 6 carbon atoms and n2 is 0 or an integer of 1 to 6), wherein arylene having 6 to 20 carbon atoms The alkylene group having 1 to 4 carbon atoms in the alkylene group having 1 to 4 carbon atoms and the arylene group having 6 to 20 carbon atoms is unsubstituted or substituted with a trifluoromethyl group or a phenyl group. there is,
provided that the number of benzene rings in the molecule is 3 or more,
Y ¹ is:

is not a group represented by]
is a compound obtained by partially (meth)acrylic modifying the epoxy resin represented by
Oligomer B is a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol AD type epoxy resin, a compound obtained by partially (meth)acrylic modifying a bisphenol A type epoxy resin, or a partially (meth)acrylic modifying bisphenol F type epoxy resin. compound and a compound obtained by partially (meth)acrylic modifying a bisphenol AD type epoxy resin, wherein the bisphenol A type epoxy resin is a condensation product of bisphenol A and epichlorohydrin. A bisphenol F type epoxy resin is an epoxy resin that is a condensation product of bisphenol F and epichlorohydrin, and a bisphenol AD type epoxy resin is an epoxy resin that is a condensation product of bisphenol AD and epichlorohydrin. There is a sealant for the liquid crystal drop method. 2. The sealant for liquid crystal dripping method according to claim 1, wherein the oligomer A is a compound having three or more benzene rings in one molecule and a bisphenol F type structure . 3. The sealant for liquid crystal dripping method according to claim 1 , wherein the oligomer B is a bisphenol F type epoxy resin or a compound obtained by partially (meth)acrylic modifying a bisphenol F type epoxy resin.