TW202221098A - Sealing material for organic el display element, cured article thereof and organic el display device - Google Patents

Abstract

A sealing material for an organic EL display element comprising a compound (A) having a (meth)acrylic acid thio group represented by the following general formula (1). [In the general formula (1), R1 represents a hydrogen atom or a methyl group, and * represents a bonding position.].

Description

Sealing material for organic EL display element, cured product thereof, and organic EL display device

The present invention relates to a sealing material for an organic electroluminescence (EL) display element, a cured product thereof, and an organic EL display device.

In the field of organic EL display elements, studies have been conducted to improve the properties of a sealing material for sealing organic EL display elements.

Since organic EL display elements consume less power, they are gradually being used in displays, lighting devices, and the like. Since organic EL display elements are easily degraded by moisture or oxygen in the atmosphere, they are sealed and used by various sealing members. For practical use, it is desired to improve the durability of various sealing members against moisture or oxygen.

As a sealing method of an organic EL display element, the method of laminating|stacking an inorganic material and an organic material alternately, and sealing is mentioned. For example, a method of forming a sealing layer after covering the element with the inorganic material film of the first layer, and then covering the inorganic material film of the second layer can be used. Since these inorganic material films have a high refractive index, in order to suppress reflection of light generated at the interface with the inorganic material film, a high refractive index is required for the sealing layer in contact with the inorganic material film.

Here, as a method of covering a sealing layer with an inorganic material film, the method of forming the inorganic material film containing silicon nitride or silicon oxide by vapor deposition is mentioned, for example. As a vapor deposition method, a sputtering method, an electron cyclotron resonance plasma chemical vapor deposition (chemical vapor deposition, CVD) method, etc. are mentioned. At the time of vapor deposition, since the surface of the sealing layer is exposed to plasma, the sealing layer is also required to be resistant to plasma, that is, to be less likely to be deteriorated by plasma treatment or the like.

Patent Document 1 describes a composition for sealing an organic light-emitting element containing a sulfur-based photocurable monomer, a non-sulfur-based photocurable monomer, and a polymerization initiator. Patent Document 2 describes a resin composition containing a cyclic (meth)acrylate compound and a polymerization initiator. Patent Document 3 describes a curable composition comprising a thioepoxy resin obtained by polymerizing a thioepoxy group-containing fluorene derivative and a dithiol compound. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Publication No. 2019-537217 [Patent Document 2] Japanese Patent Laid-Open No. 2014-229496 [Patent Document 3] Japanese Patent Laid-Open No. 2019-172880

[The problem to be solved by the invention]

As described above, in order to suppress the reflection of light generated at the interface with the inorganic material film, a high refractive index is required for the cured product of the sealing material of the organic EL display device. In this respect, the refractive index of the cured product of the resin composition described in Patent Document 1 and Patent Document 2 is as low as less than 1.60, and there is room for improvement. In addition, the resin composition in Patent Document 2 may have low plasma resistance depending on the type of the (meth)acrylate compound. Furthermore, since the resin composition described in Patent Document 3 has a high viscosity, there is room for improvement in applicability by screen printing or inkjet.

This invention is made in view of the description of these patent documents, and provides the sealing material for organic electroluminescent display elements which is excellent in the balance of viscosity, plasma resistance, and the refractive index at the time of making a cured product. [Means of Solving Problems]

[所述通式（1）中，R ₁表示氫原子或甲基，*表示鍵結位置。] [2] 如[1]所述的有機EL顯示元件用密封材，其中所述化合物（A）為具有兩個以上的所述(甲基)丙烯酸硫基的化合物。 [3] 如所述[1]或[2]所述的有機EL顯示元件用密封材，更含有具有(甲基)丙烯酸基的化合物（B）（其中所述化合物（A）除外）。 [4] 如所述[3]所述的有機EL顯示元件用密封材，其中所述化合物（B）為更具有可經取代的芳香族基的化合物。 [5] 如所述[1]至[4]中任一項所述的有機EL顯示元件用密封材，其中利用E型黏度計測定的25℃、20 rpm下的黏度為5 mPa·s以上且50 mPa·s以下。 [6] 如所述[1]至[5]中任一項所述的有機EL顯示元件用密封材，用於利用噴墨法進行的塗佈。 [7] 如所述[1]至[6]中任一項所述的有機EL顯示元件用密封材，於具有依序積層有機EL顯示元件、第一無機材料膜、密封層、第二無機材料膜的結構的有機EL顯示裝置中，用於所述密封層的形成。 [8] 如所述[1]至[7]中任一項所述的有機EL顯示元件用密封材，於使用阻擋材與填充材的密封結構中，用作所述填充材。 [9] 一種硬化物，是將如所述[1]至[8]中任一項所述的有機EL顯示元件用密封材硬化而成。 [10] 一種有機EL顯示裝置，包含： 有機EL顯示元件；以及 密封層，包覆所述有機EL顯示元件， 所述密封層含有如所述[9]所述的硬化物。 [發明的效果] ADVANTAGE OF THE INVENTION According to this invention, the sealing material for organic EL display elements shown below, the hardened|cured material thereof, and an organic EL display device can be provided. [1] A sealing material for an organic EL display element, comprising a compound (A) having a (meta)acrylic thio group represented by the following general formula (1). [hua 1]

[In the general formula (1), R ₁ represents a hydrogen atom or a methyl group, and * represents a bonding position. ] [2] The sealing material for organic EL display elements according to [1], wherein the compound (A) is a compound having two or more of the (meth)acrylic thio groups. [3] The sealing material for an organic EL display element according to the above [1] or [2], further comprising a compound (B) having a (meth)acrylic group (except for the compound (A)). [4] The sealing material for an organic EL display element according to the above [3], wherein the compound (B) is a compound further having a substituted aromatic group. [5] The sealing material for an organic EL display element according to any one of the above [1] to [4], wherein the viscosity at 25° C. and 20 rpm measured by an E-type viscometer is 5 mPa·s or more and 50 mPa·s or less. [6] The sealing material for organic EL display elements according to any one of the above [1] to [5], which is used for coating by an inkjet method. [7] The sealing material for an organic EL display element according to any one of the above [1] to [6], wherein the organic EL display element, the first inorganic material film, the sealing layer, the second inorganic material are laminated in this order In an organic EL display device having a structure of a material film, it is used for the formation of the sealing layer. [8] The sealing material for organic EL display elements according to any one of the above [1] to [7], which is used as the filler in a sealing structure using a barrier material and a filler. [9] A cured product obtained by curing the sealing material for an organic EL display element according to any one of the above [1] to [8]. [10] An organic EL display device, comprising: an organic EL display element; and a sealing layer covering the organic EL display element, wherein the sealing layer contains the cured product according to the above [9]. [Effect of invention]

ADVANTAGE OF THE INVENTION According to this invention, the sealing material for organic electroluminescent display elements which is excellent in the balance of viscosity, plasma resistance, and the refractive index when used as a cured product can be provided.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in all drawings, the common code|symbol is attached|subjected to the same component, and description is abbreviate|omitted suitably. In addition, in this embodiment, each component may be used individually by 1 type, and may be used in combination of 2 or more types. In addition, "-" which shows a numerical range shows above and below, and includes both an upper limit value and a lower limit value.

[所述通式（1）中，R ₁表示氫原子或甲基，*表示鍵結位置。] <Sealing material for organic EL display elements> (Compound (A)) In the present embodiment, the sealing material for organic EL display elements (hereinafter, also abbreviated as “sealing material” appropriately) contains a compound having the following general formula (1) The compound (A) of the (meth)acrylic thio group shown. The sealing material of the present embodiment is excellent in the balance of viscosity, plasma resistance, and refractive index when used as a cured product. [hua 1]

[In the general formula (1), R ₁ represents a hydrogen atom or a methyl group, and * represents a bonding position. ]

From the viewpoint of increasing the refractive index of the cured product of the sealing material, the compound (A) is preferably a compound having two or more (meth)acrylic thio groups.

[所述通式（2）中，R ₁與通式（1）的定義為相同含義，R ₂表示可經取代的脂肪族基、可經取代的脂環族基、可經取代的芳香族基或可經取代的雜環基，所述脂肪族基及所述脂環族基具有氧原子或硫原子，n表示1以上的整數。] As a compound (A), the compound represented by the following general formula (2) is mentioned. [hua 2]

[In the general formula (2), R ₁ has the same meaning as the general formula (1), and R ₂ represents a substituted aliphatic group, a substituted alicyclic group, a substituted aromatic group group or a substituted heterocyclic group, the aliphatic group and the alicyclic group have an oxygen atom or a sulfur atom, and n represents an integer of 1 or more. ]

From the viewpoint of reducing the viscosity of the sealing material, R ₂ preferably has 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and still more preferably 1 to 10 carbon atoms.

From the viewpoint of adjusting the polymerization rate of the sealing material and increasing the refractive index of the cured product of the sealing material, in the general formula (2), n is preferably 2 or more. In addition, the upper limit of n is not limited, and can be, for example, 12 or less, 6 or less, or 3 or less.

From the viewpoint of increasing the refractive index of the cured product of the sealing material or improving the plasma resistance of the cured product of the sealing material, in the general formula (2), R ₂ is preferably a substituted aliphatic group and a group with a sulfur atom.

The sealing material for organic EL display elements of this embodiment may contain only one type of compound (A), or may contain multiple types of compound (A). From the viewpoint of increasing the refractive index of the cured product of the sealing material or improving the plasma resistance of the cured product of the sealing material, the sealing material for organic EL display elements of the present embodiment preferably contains the general formula (2) A variety of compounds (A) differing in the value of n.

[所述通式（3）中，R ₂及n分別與通式（2）的R ₂及n的定義為相同含義。] The compound of the general formula (2) is produced by, for example, a thiol compound represented by the general formula (3) and a (meth)acrylic acid halide by dehalogenation and dehydrogenation. [hua 3]

[In the general formula (3), R ₂ and n have the same meanings as the definitions of R ₂ and n in the general formula (2), respectively. ]

In addition to a mercapto group, the thiol compound represented by the general formula (3) may have, for example, a hydroxyl group.

Specific examples of the thiol compound represented by the general formula (3) are listed below. In addition, as a specific example of R< ₂ > in general formula (2), the group derived from the following compound is mentioned.

Among the thiol compounds represented by the general formula (3), specific examples of the monothiol compound having one thiol group include methyl mercaptan, ethyl mercaptan, propyl mercaptan, and butyl thiol. Alcohol, pentyl mercaptan, hexyl mercaptan, heptyl mercaptan, octyl mercaptan, nonyl mercaptan, decyl mercaptan, undecyl mercaptan, dodecyl mercaptan, tridecyl thiol Alcohol, tetradecyl mercaptan, hexadecyl mercaptan, octadecyl mercaptan, allyl mercaptan, 2-butene-1-thiol, 1-butene-4-thiol, methyl allyl mercaptan, 1-pentenyl mercaptan, 2-isopentenyl mercaptan, oleyl mercaptan, cyclopentyl mercaptan, cyclohexyl mercaptan, cyclopentyl methyl mercaptan, cyclopentyl mercaptan Heptylthiol, 3-methylcyclopentylmethylthiol, 2-methylcyclohexylthiol, 3-methylcyclohexylthiol, 4-methylcyclohexylthiol, 3-methylcyclohexylthiol Methylthiol, 1-cyclopentylthiol, 2-cyclohexenylthiol, β-cyclohexylethylthiol, 2,2,6,6-tetramethylcyclohexylthiol, ε-ring Hexylpentyl mercaptan, cholesteryl mercaptan, furfuryl mercaptan, methyl furfuryl mercaptan, 2-mercaptothiophene, 3-mercaptothiophene, 2-ethyl-3-mercaptothiophene, thiophenol, methyl thiophene Phenol, ethylthiophenol, 2,4-thioxylenol, 2,5-thioxylenol, propylthiophenol, allylthiophenol, 2-allyl-4-methyl thiophenol, phenylthiophenol, chlorothiophenol, bromothiophenol, iodothiophenol, nitrothiophenol, trinitrothiophenol, dinitrothiophenol, nitrobromobenzene Thiophenol, Nitrochlorothiophenol, Methylsulfonylthiophenol, Benzenethiol, Benzylthiol, Nitrobenzylthiol, α-Phenylethylthiol, β-Phenylethyl Thiol, α-Phenylpropylthiol, γ-Phenylpropylthiol, β-Phenylpropylthiol, β-Phenyl-Isopropylthiol, D-β-Phenylbutylthiol Alcohol, ε-phenylpentylthiol, α,β-diphenylethylthiol, methylbenzylthiol, 2-nitro-p-tolylthiol, α-(o-tolyl)benzyl Thiol, α-(p-Tolyl)benzylthiol, Chlorobenzylthiol, Dichlorobenzylthiol, Bromobenzylthiol, α-Phenyl-p-Chlorobenzylthiol, 3-Hydroxy- 5-methylbenzyl mercaptan, cinnamyl mercaptan, β-γ-diphenylallyl mercaptan, 4,4'-dichlorobenzyl mercaptan, triphenylmethyl mercaptan, α - Thionaphthalene, β-thionaphthalene, 4-chloro-α-thionaphthalene, 4-bromo-α-thionaphthalene, 1-nitro-β-thionaphthalene, 4-nitro-α-naphthalene Thiophenol, etc.

Among the thiol compounds represented by the general formula (3), specific examples of the polythiol compound having two or more thiol groups include: Methanedithiol, 1,2-ethanedithiol, 1,1-propanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 2,2-propanedithiol , 1,6-hexanedithiol, 1,2,3-propanetrithiol, 1,1-cyclohexanedithiol, 1,2-cyclohexanedithiol, 2,2-dimethylthiol propane-1,3-dithiol, 3,4-dimethoxybutane-1,2-dithiol, 2-methylcyclohexane-2,3-dithiol, bicyclo[2, 2,1]Hept-exo-cis-2,3-dithiol, 1,1-bis(mercaptomethyl)cyclohexane, bis(2-mercaptoethyl thiomalate), 2,3 - Dimercaptosuccinic acid (2-mercaptoethyl ester), 2,3-dimercapto-1-propanol (2-mercaptoacetate), 2,3-dimercapto-1-propanol (3-mercaptoethyl ester) ester), diethylene glycol bis(2-mercaptoacetate), diethylene glycol bis(3-mercaptopropionate), 1,2-dimercaptopropyl methyl ether, 2,3-dimercapto Propyl methyl ether, 2,2-bis(mercaptomethyl)-1,3-propanedithiol, bis(2-mercaptoethyl) ether, ethylene glycol bis(2-mercaptoacetate), ethyl acetate Glycol bis(3-mercaptopropionate), Trimethylolpropane bis(2-mercaptoglycolate), Trimethylolpropane bis(3-mercaptopropionate), Pentaerythritol tetrakis(2-mercaptoglycolic acid) ester), aliphatic polythiols such as pentaerythritol tetrakis (3-mercaptopropionate), and halogen-substituted aliphatic polythiols such as chlorine and bromine substituents of these; 1,2-dimercaptobenzene, 1,3-dimercaptobenzene, 1,4-dimercaptobenzene, 1,2-bis(mercaptomethyl)benzene, 1,3-bis(mercaptomethyl)benzene, 1, 4-Bis(mercaptomethyl)benzene, 1,2-bis(mercaptoethyl)benzene, 1,3-bis(mercaptoethyl)benzene, 1,4-bis(mercaptoethyl)benzene, 1,2- Bis(mercaptomethyleneoxy)benzene, 1,3-bis(mercaptomethyleneoxy)benzene, 1,4-bis(mercaptomethyleneoxy)benzene, 1,2-bis(mercaptoethylidene) oxy)benzene, 1,3-bis(mercaptoethylideneoxy)benzene, 1,4-bis(mercaptoethylideneoxy)benzene, 1,2,3-trimercaptobenzene, 1,2, 4-Trimercaptobenzene, 1,3,5-Trimercaptobenzene, 1,2,3-Tris(mercaptomethyl)benzene, 1,2,4-Tris(mercaptomethyl)benzene, 1,3,5- Tris(mercaptomethyl)benzene, 1,2,3-tris(mercaptoethyl)benzene, 1,2,4-tris(mercaptoethyl)benzene, 1,3,5-tris(mercaptoethyl)benzene, 1,2,3-Tris(mercaptomethyleneoxy)benzene, 1,2,4-Tris(mercaptomethyleneoxy)benzene, 1,3,5-Tris(mercaptomethyleneoxy)benzene , 1,2,3-tris(mercaptoethylideneoxy)benzene, 1,2,4-tris(mercaptoethylideneoxy)benzene, 1,3,5-tris(mercaptoethylideneoxy) Benzene, 1,2,3,4-tetramercaptobenzene, 1,2,3,5-tetramercaptobenzene, 1,2,4,5-tetramercaptobenzene, 1,2,3,4-tetrakis(mercaptomethyl) yl)benzene, 1,2,3,5-tetrakis(mercaptomethyl)benzene, 1,2,4,5-tetrakis(mercaptomethyl)benzene, 1,2,3,4-tetrakis(mercaptoethyl) Benzene, 1,2,3,5-tetrakis(mercaptoethyl)benzene, 1,2,4,5-tetrakis(mercaptoethyl)benzene, 1,2,3,4-tetrakis(mercaptomethyleneoxy) ) benzene, 1,2,3,5-tetrakis(mercaptomethyleneoxy)benzene, 1,2,4,5-tetrakis(mercaptomethyleneoxy)benzene, 1,2,3,4-tetrakis (mercaptoethylideneoxy)benzene, 1,2,3,5-tetrakis(mercaptoethylideneoxy)benzene, 1,2,4,5-tetrakis(mercaptoethylideneoxy)benzene, 2, 2'-dimercaptobiphenyl, 4,4'-thiobis-benzenethiol, 4,4'-dimercaptobiphenyl, 4,4'-dimercaptobiphenyl, 2,5-toluenedithiol, 3 ,4-toluenedithiol, 1,4-naphthalenedithiol, 1,5-naphthalenedithiol, 2,6-naphthalenedithiol, 2,7-naphthalenedithiol, 2,4-dimethyl Benzene-1,3-dithiol, 4,5-dimethylbenzene-1,3-dithiol, 9,10-anthracenedimethanethiol, 1,3-bis(p-methoxyphenyl) ) propane-2,2-dithiol, 1,3-diphenylpropane-2,2-dithiol, phenylmethane-1,1-dithiol, 2,4-bis(p-mercaptophenyl ) Aromatic polythiols such as pentane and bis(4-mercaptophenyl) sulfide; 2,5-Dichlorobenzene-1,3-dithiol, 1,3-bis(p-chlorophenyl)propane-2,2-dithiol, 3,4,5-tribromo-1,2- Chlorine-substituted aromatic polythiols such as dimercaptobenzene and 2,3,4,6-tetrachloro-1,5-bis(mercaptomethyl)benzene, and halogen-substituted aromatic compounds such as bromine-substituted aromatic polythiols family of polythiols; 2-Methylamino-4,6-dithiol-s-triazine, 2-ethylamino-4,6-dithiol-s-triazine, 2-amino-4,6-dithiol - s-triazine, 2-morpholinyl-4,6-dithiol-s-triazine, 2-cyclohexylamino-4,6-dithiol-s-triazine, 2-methoxy-4, 6-Dithiol-s-triazine, 2-phenoxy-4,6-dithiol-s-triazine, 2-thiophenoxy-4,6-dithiol-s-triazine, 2- Thiobutyloxy-4,6-dithiol-s-triazine, 3,4-thiophene dithiol, bismuthiol and other heterocyclic polythiols; 1,2-bis(mercaptomethylthio)benzene, 1,3-bis(mercaptomethylthio)benzene, 1,4-bis(mercaptomethylthio)benzene, 1,2-bis(mercaptoethylthio) Benzene, 1,3-bis(mercaptoethylthio)benzene, 1,4-bis(mercaptoethylthio)benzene, 1,2,3-tris(mercaptomethylthio)benzene, 1,2,4-tris (Mercaptomethylthio)benzene, 1,3,5-tris(mercaptomethylthio)benzene, 1,2,3-tris(mercaptoethylthio)benzene, 1,2,4-tris(mercaptoethylthio) ) benzene, 1,3,5-tris(mercaptoethylthio)benzene, 1,2,3,4-tetrakis(mercaptomethylthio)benzene, 1,2,3,5-tetrakis(mercaptomethylthio) Benzene, 1,2,4,5-tetrakis(mercaptomethylthio)benzene, 1,2,3,4-tetrakis(mercaptoethylthio)benzene, 1,2,3,5-tetrakis(mercaptoethylthio) ) polythiols derived from nuclear alkylates of aromatic compounds, such as benzene, 1,2,4,5-tetrakis(mercaptoethylthio)benzene; bis(mercaptomethyl)sulfide, bis(mercaptoethyl)sulfide, bis(mercaptopropyl)sulfide, bis(mercaptomethylthio)methane, bis(2-mercaptoethylthio)methane, bis(3 -Mercaptopropylthio)methane, 1,2-bis(mercaptomethylthio)ethane, 1,2-bis(2-mercaptoethylthio)ethane, 1,2-bis(3-mercaptopropyl) Ethane, 1,3-bis(mercaptomethylthio)propane, 1,3-bis(2-mercaptoethylthio)propane, 1,3-bis(3-mercaptopropylthio)propane, 1,2, 3-Tris(Mercaptomethylthio)propane, 1,2,3-Tris(2-Mercaptoethylthio)propane, 1,2,3-Tris(3-Mercaptopropylthio)propane, Tetrakis(Mercaptomethylthio) methyl)methane, tetrakis(2-mercaptoethylthiomethyl)methane, tetrakis(3-mercaptopropylthiomethyl)methane, bis(2,3-dimercaptopropyl)sulfide, 2,5- Aliphatic polythiols such as dimercapto-1,4-dithiane, bis(mercaptomethyl)disulfide, bis(mercaptoethyl)disulfide, bis(mercaptopropyl)disulfide, and these thioglycolate and mercaptopropionate; Hydroxymethyl sulfide bis(2-mercaptoacetate), hydroxymethyl sulfide bis(3-mercaptopropionate), hydroxyethyl sulfide bis(2-mercaptoacetate), hydroxyethyl sulfide Bis(3-mercaptopropionate), hydroxypropyl sulfide bis(2-mercaptoacetate), hydroxypropyl sulfide bis(3-mercaptopropionate), hydroxymethyl disulfide bis(2-mercaptopropionate) mercaptoacetate), hydroxymethyl disulfide bis(3-mercaptopropionate), hydroxyethyl disulfide bis(2-mercaptoacetate), hydroxyethyl disulfide bis(3-mercaptopropionate) ester), hydroxypropyl disulfide bis(2-mercaptoacetate), hydroxypropyl disulfide bis(3-mercaptopropionate), 2-mercaptoethyl ether bis(2-mercaptoacetate) ), 2-mercaptoethyl ether bis(3-mercaptopropionate), 1,4-dithiane-2,5-diol bis(2-mercaptoacetate), 1,4-dithiane- 2,5-diol bis(3-mercaptopropionate), thiodiglycolate bis(2-mercaptoethyl), thiodipropionate bis(2-mercaptoethyl), 4,4 - bis(2-mercaptoethyl) thiodibutylate, bis(2-mercaptoethyl) dimercaptoacetate, bis(2-mercaptoethyl) dithiodipropionate, 4,4- Bis(2-mercaptoethyl dithiodibutylate), bis(2,3-dimercaptopropyl thiodiglycolate), bis(2,3-dimercaptopropyl thiodipropionate) esters of aliphatic polythiols such as bis(2,3-dimercaptopropyl ester), dimercaptoacetic acid bis(2,3-dimercaptopropyl ester), and dithiodipropionic acid bis(2,3-dimercaptopropyl ester); 2-mercaptoethanol, 3-mercapto-1,2-propanediol, glycerol bis(mercaptoacetate), 1-hydroxy-4-mercaptocyclohexane, 2,4-dimercaptophenol, 2-mercaptohydroquinone , 4-mercaptophenol, 3,4-dimercapto-2-propanol, 1,3-dimercapto-2-propanol, 2,3-dimercapto-1-propanol, 1,2-dimercapto-1 ,3-Butanediol, Pentaerythritol tris(3-mercaptopropionate), Pentaerythritol mono(3-mercaptopropionate), Pentaerythritol bis(3-mercaptopropionate), Pentaerythritol tris(mercaptoacetate), Pentaerythritol Penta(3-mercaptopropionate), hydroxymethyl-tris(mercaptoethylthiomethyl)methane, 1-hydroxyethylthio-3-mercaptoethylthiobenzene, 4-hydroxy-4'-mercaptodiphenyl Ethyl, 2-(2-mercaptoethylthio)ethanol, dihydroxyethyl sulfide mono(3-mercaptopropionate), dimercaptoethane mono(salicylate), hydroxyethylthio Methyl-tris(mercaptoethylthiomethyl)methane, 2,2'-((3-mercaptopropane-1,2-diyl)bis(sulfanediyl))bis(ethane-1-thiol ), 3,3'-thiobis(2-((2-mercaptoethyl)thio)propane-1-thiol) and other polythiols. Further, halogen-substituted products such as these chlorine-substituted products and bromine-substituted products can be mentioned.

(Compound (B)) The sealing material for organic EL display elements of this embodiment may further contain a compound (B). The compound (B) is a (meth)acrylic group-containing compound (except for the compound (A)). Here, in this specification, a (meth)acryloyl group means at least one of an acryl group and a methacryloyl group. In addition, the term "(meth)acrylic acid" refers to at least one of acrylic acid and methacrylic acid. In addition, the term "(meth)acrylate" means at least one of acrylate and methacrylate.

Specific examples of the (meth)acrylic compound having a (meth)acryloyl group include a monofunctional mono(meth)acrylic compound, a difunctional di(meth)acrylic compound, and a trifunctional or higher poly(meth)acrylic compound. Functional (meth)acrylic compounds.

Specific examples of the mono(meth)acrylic acid compound include isobornyl (meth)acrylate, dicyclopentyl (meth)acrylate, and 3,3,5-trimethyl (meth)acrylate Hexyl ester, 4-tert-butylcyclohexyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 2-hydroxy (meth)acrylate Ethyl ester, 4-hydroxybutyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, isooctyl (meth)acrylate, 2-methyl (meth)acrylate Oxyethyl ester, methoxytriethylene glycol (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, (meth)acrylic acid Ethoxyethyl ester, (meth)acrylate butoxyethyl ester, ethoxydiethylene glycol (meth)acrylate, (meth)acrylate methoxybisyl ethyl ester, diethylene glycol (meth) Ethyl Acrylate, Cyclic Trimethylolpropane Felmer Mono(Meth)acrylate, Imide (Meth)acrylate, Isoamyl (Meth)acrylate, Ethoxylated Succinic Acid (Meth)Acrylic Acid ester, trifluoroethyl (meth)acrylate, ω-carboxypolycaprolactone mono(meth)acrylate, cyclohexyl (meth)acrylate, 2-(2-ethoxyethyl) (meth)acrylate Oxy)ethyl ester, stearyl (meth)acrylate, diethylene glycol monobutyl ether (meth)acrylate, lauryl (meth)acrylate, isodecyl (meth)acrylate, (meth)acrylate Isooctyl acrylate, octyl/decyl (meth)acrylate, tridecyl (meth)acrylate, caprolactone (meth)acrylate, ethoxylated (4) nonylphenol (meth) Acrylate, Methoxy polyethylene glycol (350) mono(meth)acrylate, Methoxy polyethylene glycol (550) mono(meth)acrylate, phenoxyethyl (meth)acrylate, Cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, benzyl (meth)acrylate, methylphenoxyethyl (meth)acrylate, caprolactone-modified (meth)acrylic acid Tetrahydrofurfuryl, Tribromophenyl (meth)acrylate, Tribromophenyl (meth)acrylate ethoxylate, 2-phenoxyethyl (meth)acrylate, 2-benzene (meth)acrylate Ethylene oxide adduct of oxyethyl ester, propylene oxide adduct of 2-phenoxyethyl (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, (methyl) ) 2-hydroxy-3-phenoxypropyl acrylate, 3-methacryloyloxymethylcyclohexene oxide, and 3-(meth)acryloyloxymethylcyclohexene oxide, and the like. In addition, as a specific product name and acquirer of the mono(meth)acrylic acid compound, ethoxylated o-phenylphenol acrylate (NK Ester) A-LEN-10, manufactured by Shin-Nakamura Chemical Industry Co., Ltd. ), m-phenoxybenzyl acrylate (Light Acrylate POB-A, manufactured by Kyōeisha Chemical Co., Ltd.), etc.

Specific examples of the di(meth)acrylic compound include di(meth)acrylates of diols, di(meth)acrylates of (poly)alkanediols, and the like. In addition, as a specific product name and acquirer of the di(meth)acrylic acid compound, 1,6-hexanediol diacrylate (NK Ester) A-HD-N, Shin-Nakamura Chemical Industry Co., Ltd. Manufacturing; Light Acrylate 1,6HX-A, manufactured by Kyōeisha Chemical Co., Ltd.), 1,9-nonanediol diacrylate (NK Ester A-NOD-N, Shin-Nakamura Chemical Industry Co., Ltd. Manufactured by the company; Light Acrylate 1,9ND-A, manufactured by Kyeisha Chemical Co., Ltd., 1,10-decanediol diacrylate (NK Ester) A-DOD-N, Shin-Nakamura Chemical Industrial Co., Ltd.), neopentyl glycol diacrylate (NK Ester A-NPG, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.; Light Acrylate NP-A, manufactured by Kyeisha Chemical Co., Ltd.), B Glycol diacrylate (SR206NS, manufactured by Arkema), polyethylene glycol diacrylate (NK Ester A-400, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), polypropylene glycol diacrylate ( NK Ester (NK Ester) APG-400, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), tricyclodecane dimethanol diacrylate (alias: dimethylol-tricyclodecane diacrylate) (NK Ester (NK Ester) A-DCP, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.; Light Acrylate (DCP-A, manufactured by Kyōeisha Chemical Co., Ltd.), 1,3-butanediol dimethacrylate (NK Ester) BG , manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), 1,4-butanediol dimethacrylate (NK Ester (NK Ester) BD, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), 1,6-hexanediol dimethacrylate (NK Ester HD-N, manufactured by Shin-Nakamura Chemical Industries, Ltd.), 1,9-nonanediol dimethacrylate (NK Ester (NK Ester) NOD-N, manufactured by Shin-Nakamura Chemical Industries, Ltd.), 1,10-Decanediol dimethacrylate (NK Ester (NK Ester) DOD-N, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), 1,12-dodecanediol diacrylate (SR262, Sadolan ( Sartomer), neopentyl glycol dimethacrylate (NK Ester NPG, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), etc.

Specific product names and acquirers of the polyfunctional (meth)acrylic compound include: Trimethylolpropane triacrylate (NK Ester) A-TMPT, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.; Wright Acrylate (Light Acrylate) TMP-A, manufactured by Kyeisha Chemical Co., Ltd.), ethoxylated trimethylolpropane triacrylate (NK Ester (NK Ester) A-TMPT-EO, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), ethyl acetate Oxylated glycerol triacrylate (NK Ester (NK Ester) A-GLY-6E, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), propoxylated glycerol triacrylate (NK Ester (NK Ester) A-GLY-3P, new Trifunctional (meth)acrylic compounds such as Nakamura Chemical Industry Co., Ltd.; Pentaerythritol tetraacrylate (NK Ester A-TMMT, manufactured by Shin-Nakamura Chemical Industries, Ltd.), ethoxylated pentaerythritol tetraacrylate (NK Ester (NK Ester) ATM-4E, manufactured by Shin-Nakamura Chemical Industries, Ltd.), Tetrafunctional (meth)acrylic compounds such as di-trimethylolpropane tetraacrylate (NK Ester AD-TMP-L, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.); Pentafunctional (meth)acrylic compounds such as dipentaerythritol pentaacrylate (M-402, manufactured by Toa Gosei Corporation); Hexafunctional (meth)acrylic compounds such as dipentaerythritol hexaacrylate (GM66G0H, manufactured by Guojing Chemical Co., Ltd.), and the like.

From the viewpoint of increasing the refractive index of the cured product of the sealing material, the compound (B) is preferably a compound having a more substituted aromatic group. As a specific example of the aromatic group which may be substituted in the compound (B), the aromatic group which may be substituted in the group derived from the compound exemplified as the thiol compound represented by the general formula (3) can be applied. base.

From the viewpoint of increasing the strength of the cured product of the sealing material, the total amount of the compound (A) and the compound (B) is preferably 70% by mass or more with respect to the entire composition of the sealing material of the present embodiment, more preferably 90 mass % or more, more preferably 95 mass % or more, still more preferably 99 mass % or more.

The compound (A) is preferably 50 parts by mass or more and 100 parts by mass or less, more preferably 60 parts by mass or more and 100 parts by mass or less, based on 100 parts by mass of the compound (A) and the compound (B) in total. In addition, the compound (A) may be, for example, 70 parts by mass or more and 100 parts by mass or less and 80 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the total of the compound (A) and the compound (B).

The compound (B) is preferably 0 parts by mass or more and 50 parts by mass or less, more preferably 0 parts by mass or more and 40 parts by mass or less, with respect to 100 parts by mass of the compound (A) and the compound (B) in total. In addition, the compound (B) may be, for example, 0 parts by mass or more and 30 parts by mass or less, for example, 0 parts by mass or more and 20 parts by mass or less, based on 100 parts by mass of the compound (A) and the compound (B) in total.

(polymerization initiator) The sealing material of this embodiment may further contain a polymerization initiator. From the viewpoint of stably forming a cured product at a low temperature, the polymerization initiator is preferably a compound that generates a radical or an acid by irradiation with ultraviolet rays or visible rays, that is, a photopolymerization initiator. As the photopolymerization initiator, an acylphosphine oxide-based initiator, an oxyphenylacetate-based initiator, a benzalic acid-based initiator, a hydroxyphenyl ketone-based initiator, and the like can be mentioned.

Specific examples of the photopolymerization initiator include benzophenone, Michler's ketone, 4,4'-bis(diethylamino)benzophenone, xanthone, and thioxanthone , Isopropylxanthone, 2,4-diethylthioxanthone, 2-ethylanthraquinone, acetophenone, 2-hydroxy-2-methyl-4'-isopropylpropiophenone, Isopropyl benzoin ether, isobutyl benzoin ether, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, camphorquinone, benzoanthrone, 4 - Ethyl dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, 4,4'-bis(tert-butylperoxycarbonyl)benzophenone, 3,4,4 '-Tris(tert-butylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(tert-butylperoxycarbonyl)benzophenone, 3,3',4 ,4'-Tetrakis(3rd-hexylperoxycarbonyl)benzophenone, 3,3'-bis(methoxycarbonyl)-4,4'-bis(tert-butylperoxycarbonyl)diphenyl Methanone, 3,4'-bis(methoxycarbonyl)-4,3'-bis(tert-butylperoxycarbonyl)benzophenone, 4,4'-bis(methoxycarbonyl)- 3,3'-bis(tert-butylperoxycarbonyl)benzophenone, 2-(4'-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine , 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2',4'-dimethoxystyrene base)-4,6-bis(trichloromethyl)-s-triazine, 2-(2'-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2 -(4'-Pentoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 4-[p-N,N-bis(ethoxycarbonylmethyl)]-2 ,6-bis(trichloromethyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(2'-chlorophenyl)-s-triazine, 1,3-bis(trichlorophenyl) Methyl)-5-(4'-methoxyphenyl)-s-triazine, 2-(p-dimethylaminostyryl)benzoxazole, 2-(p-dimethylaminostyrene yl)benzothiazole, 2-mercaptobenzothiazole, 3,3'-carbonylbis(7-diethylaminocoumarin), 2-(o-chlorophenyl)-4,4',5,5 '-Tetraphenyl-1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)- 1,2'-biimidazole, 2,2'-bis(2,4-dichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2 '-Bis(2,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4,6-tri Chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 3-(2-methyl-2-dimethylaminopropionyl)carbazole, 3 ,6-bis(2-methyl-2-morpholinopropionyl)-9-n-dodecylcarbazole, bis(η5-2,4-cyclopentadien-1-yl)-bis( 2,6-Difluoro- 3-(1H-pyrrol-1-yl)-phenyl) titanium, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1-[4-( 2-Hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propanone, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl )-benzyl]phenyl}-2-methyl-1-propanone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2-( Dimethylamino)-1-(4-morpholinylphenyl)-2-benzyl-1-butanone, 2-(dimethylamino)-2-[(4-methylphenyl) Methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone, oxy-phenyl-acetic acid 2-[2-oxo-2-phenyl-acetoxy- Ethoxy]-ethyl ester, oxy-phenyl-acetic acid 2-[2-hydroxy-ethoxy]-ethyl ester, methyl benzallate, bis(2,4,6-trimethyl) benzyl) phenylphosphine oxide, 2,4,6-trimethylbenzyldiphenylphosphine oxide, 2,4,6-trimethylbenzyldiphenylphosphonate, 1-[4-(Phenylthio)phenyl]-1,2-octanedione 2-(O-benzyl oxime), 1-[9-ethyl-6-(2-methylbenzyl) Acetyl)-9H-carbazol-3-yl]-ethanone-1-(O-acetyloxime) and the like.

From the viewpoint of improving the curability of the sealing material, the photopolymerization initiator is preferably selected from 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1-hydroxycyclohexyl phenyl ketone, -[4-(2-Hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propanone, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl yl-propionyl)-benzyl]phenyl}-2-methyl-1-propanone, 2,2-dimethoxy-2-phenylacetophenone, oxy-phenyl-acetic acid 2-[ 2-oxo-2-phenyl-acetoxy-ethoxy]-ethyl ester, oxy-phenyl-acetic acid 2-[2-hydroxy-ethoxy]-ethyl ester, benzyl methyl carboxylate, bis(2,4,6-trimethylbenzyl)phenylphosphine oxide, 2,4,6-trimethylbenzyldiphenylphosphine oxide (2,4,6 -trimethyl benzoyl diphenyl phosphine oxide (TPO), 2,4,6-trimethylbenzyl diphenyl phosphonate, one or more compounds in the group.

Specific product names and acquirers of photopolymerization initiators include: Irgacure 184, Irgacure 651, Irgacure 127, Irgacure 1173, Irgacure 500, Irgacure 2959, Irgacure 754, Irgacure MBF, Irgacure TPO (the above are manufactured by BASF), Omnirad TPO H (manufactured by IGM Resins), etc.

From the viewpoint of improving the hardenability of the sealing material, the content of the polymerization initiator is preferably 0.1 mass % or more, more preferably 0.5 mass % or more, and further preferably 1 mass % or more with respect to the entire composition of the sealing material, More preferably, it is 2 mass % or more.

In addition, from the viewpoint of suppressing coloration of the sealing material, the content of the polymerization initiator is preferably 10 mass % or less, more preferably 8 mass % or less, and further preferably 6 mass % or less with respect to the entire composition of the sealing material. , and more preferably 5 mass % or less.

(other ingredients) The sealing material of the present embodiment may contain an agent selected from the group consisting of an adhesion imparting agent, a filler, a hardening accelerator, a plasticizer, a surfactant, a heat stabilizer, an antioxidant, a flame retardant, an antistatic agent, a defoaming agent, a leveling agent One or two or more components from the group consisting of a UV absorber and an ultraviolet absorber are used as components other than those described above (other components). The content of other components is preferably 5 mass % or less, more preferably 1 mass % or less, with respect to the entire composition of the sealing material.

From the viewpoint of improving the thermal stability of the sealing material, the sealing material preferably contains a heat stabilizer. As the heat stabilizer, a hindered phenol compound can be used. Examples of the hindered phenol compound include dibutylhydroxytoluene (alias: 2,6-bis(1,1-dimethylethyl)-4-methylphenol) (product name BHT, manufactured by Wako Pure Chemical Industries, Ltd.) , 3,5-di-tert-butyl-4-hydroxytoluene, pentaerythritol tetrakis [3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (product name Yilunuo IRGANOX 1010, manufactured by BASF (BASF); product name Adekastab (Adekastab) AO-60, manufactured by Adeka (ADEKA)), octadecyl-3-(3,5-di -Tertiary butyl-4-hydroxyphenyl) propionate (product name IRGANOX 1076, manufactured by BASF) and the like. From the viewpoint of further improving the thermal stability of the sealing material, the sealing material preferably contains dibutylhydroxytoluene and pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propane] at least one of acid esters].

As the antioxidant, a phosphorus-based antioxidant can be used. Examples of phosphorus-based antioxidants include phosphites, and for example, 2,2-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite (product name: Edikostapo) (Adekastab) HP-10, manufactured by ADEKA Corporation), tris(2,4-di-tert-butylphenyl) phosphite (product name IRGAFOS) 168, BASF (BASF) ) made by the company) etc.

(Characteristics of sealing material) The properties of the sealing material of the present embodiment are not limited, but from the viewpoint of suitability for application such as ink jet method, it is preferably liquid.

Moreover, in embodiment, from a viewpoint of stably forming a sealing layer, it is preferable that a sealing material is a sealing material for coating, and it is more preferable that it is a sealing material for coating by an inkjet method.

From the viewpoint of improving the inkjet ejectability, the viscosity of the sealing material measured at 25°C and 20 rpm using an E-type viscometer is preferably 5 mPa·s or more, more preferably 8 mPa·s or more, and still more preferably 10 mPa·s or more. In addition, from the viewpoint of improving the ink jet dischargeability, the viscosity of the sealing material is preferably 50 mPa·s or less, more preferably 40 mPa·s or less, and still more preferably 30 mPa·s or less.

(Manufacturing method of sealing material) The manufacturing method of a sealing material is demonstrated. The manufacturing method of a sealing material is not limited, For example, a compound (A), an appropriate compound (B), other components, for example, various additives added as needed are included. As a method of mixing each component, for example, the following methods are exemplified: known methods such as planetary stirrers, homodispersers, universal mixers, Banbury mixers, kneaders, twin rolls, triple rolls, and extruders are used alone or in combination. Various kneaders are used for uniform kneading under the conditions of normal temperature or heating, normal pressure, reduced pressure, pressure or inert gas flow.

<hardened product> The cured product of the sealing material of the present embodiment is obtained by curing the sealing material of the present embodiment. For example, the hardened|cured material of the sealing material of this embodiment is obtained by apply|coating and hardening the sealing material of this embodiment on a base material. For the coating, known methods such as ink jet method, screen printing, and dispersion machine coating can be used.

Hardening can be performed by drying the sealing material applied on the substrate. As a method of drying the sealing material, for example, it can be performed by heating to a temperature at which the compound (A) does not polymerize. The shape of the hardened|cured material obtained by hardening a sealing material is not restrict|limited, For example, it can be made into a film shape or a layer shape.

In addition, photocuring may be performed on the sealing material applied on the base material. As a method of photohardening the sealing material, for example, the following methods can be mentioned: using a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, an excimer laser, a chemical lamp, a black light lamp, a microwave excited mercury lamp, a metal halide lamp, Light sources such as sodium lamps, halogen lamps, xenon lamps, ultraviolet-light emitting diodes (UV-LEDs), and other LED lamps, fluorescent lamps, sunlight, and electron beam irradiation devices are used for light irradiation and curing.

The refractive index (nd) of the d-ray (wavelength: 587.6 nm) of the cured product of the sealing material of the present embodiment at room temperature (25° C.) is preferably 1.60 or more, more preferably 1.61 or more, still more preferably 1.62 or more, and further It is preferably 1.63 or more, more preferably 1.64 or more, still more preferably 1.65 or more. In addition, the upper limit of the refractive index is not limited, but can be, for example, 2.00 or less, 1.90 or less, or 1.80 or less. The refractive index of the sealing material after hardening can be measured with an Abbe refractometer.

The cured product of the sealing material can be used as a sealing material for sealing the organic EL display element. According to the cured product of the sealing material of the present embodiment, since the refractive index is high and the plasma resistance is excellent, it is preferable as a sealing material.

<Organic EL display device> The organic EL display device of this embodiment includes: an organic EL display element; and a sealing layer including a cured product of the sealing material of this embodiment. By having the sealing layer, the organic EL display element disposed on the substrate is sealed with the sealing layer, and the penetration of moisture into the organic EL display element can be sufficiently prevented, and the performance and durability of the organic EL display element can be maintained high.

The sealing layer can also be covered with an inorganic material film. In addition, the organic EL display element arrange|positioned on a board|substrate may be covered with an inorganic material film in advance before sealing with a sealing layer.

Specifically, in an organic EL display device having a structure in which an organic EL display element, a first inorganic material film, a sealing layer, and a second inorganic material film are laminated in this order, the sealing material of this embodiment is used for the sealing layer. form.

FIG. 1 is a cross-sectional view showing a configuration example of an organic EL display device of the present embodiment. In the organic EL display device 100 shown in FIG. 1 , the organic EL display element 10 is disposed on the substrate 50 , and the surface of the organic EL display element 10 is covered with the first inorganic material film 21 . The organic EL display element 10 covered with the first inorganic material film 21 is sealed with the first sealing layer 22 . The surface of the first sealing layer 22 is further covered with the second inorganic material film 23 . The first sealing layer 22 covered with the second inorganic material film 23 is further sealed with the second sealing layer 24 . A surface protection layer 25 is disposed on the surface of the second sealing layer 24 .

The organic EL display device 100 may be a top emission structure or a bottom emission structure.

The material of the base material 50 is not limited, for example, various materials such as a glass substrate, a silicon substrate, and a plastic substrate can be used. A TFT substrate including a plurality of thin film transistors (TFTs) and a planarization layer on the substrate can also be used.

Examples of inorganic materials constituting the first inorganic material film 21 and the second inorganic material film 23 include silicon nitride (SiN _x ), silicon oxide (SiO _x ), aluminum oxide (Al ₂ O ₃ ), and the like. The inorganic material film may be a single layer or a laminate of a plurality of layers.

As a coating method using the first inorganic material film 21 and the second inorganic material film 23, for example, in the case where the inorganic material film includes silicon nitride or silicon oxide, sputtering or electron cyclotron resonance plasma CVD can be used. law, etc.

Among them, the sputtering method can be carried out, for example, using a single gas such as argon or nitrogen or a mixed gas as a carrier gas, under the conditions of room temperature, electric power of 50 W to 1000 W, and pressure of 0.001 Torr (Torr) to 0.1 Torr.

In addition, the electron cyclotron resonance plasma CVD method can use, for example, a mixed gas of SiH ₄ and O ₂ or a mixed gas of SiH ₄ and N ₂ at a temperature of 30°C to 100°C, a pressure of 10 mTorr to 1 Torr, a frequency of 2.45 GHz, and electric Under the conditions of 10 W to 1000 W.

Since the sealing layer of the present embodiment is excellent in plasma resistance, even if an inorganic material film is formed on the surface by plasma treatment such as electron cyclotron resonance plasma CVD, the resin layer is not easily deteriorated, and damage to the organic EL light-emitting element can be suppressed. .

The thicknesses of the first inorganic material film 21 and the second inorganic material film 23 are not limited, but from the viewpoint of improving the barrier performance, they are, for example, 0.01 μm to 10 μm, preferably 0.1 μm to 5 μm.

As a method of obtaining a sealing layer, the method of coating and hardening a sealing material, etc. are mentioned. As a coating method, an ink jet method can be used. In addition, the sealing material can be coated in a planar shape by methods such as screen printing, dispersion machine coating, ink jet printing, slit coating, and spray coating.

The thickness of the sealing layer is not limited, but from the viewpoint of improving sealing performance and flexibility, it is, for example, 0.1 μm to 50 μm, or preferably 1 μm to 20 μm.

Furthermore, as a method of sealing the organic EL display element, there is a method of forming a barrier layer around the organic EL display element with a high-viscosity curable resin (barrier), and pouring a low-viscosity curable resin (filler) into the barrier layer. ) to harden it. In the sealing structure using such a barrier material and a filler, the sealing material of this embodiment can be used as a filler. Since the sealing material of this embodiment has a low viscosity and is excellent in fluidity, it can be suitably used as a filler. [Example]

Hereinafter, the present invention will be described with reference to Examples and Comparative Examples, but the present invention is not limited to these.

(production of sealing material) First, the materials used in the following examples are shown.

硫代化合物A2：依照日本專利2708607號公報的實施例3的記載而製備的下述式的化合物 [化5]

硫代化合物A3：依照日本專利特開平9-324023號公報的合成例6的記載而製備的下述式的化合物 [化6]

硫代化合物A4：除將日本專利2708607號公報的實施例1的4,4'-硫雙-苯硫醇25.0份（0.10莫耳）替換為苄基硫醇24.8份（0.20莫耳）以外，藉由進行與日本專利2708607號公報的實施例1相同的操作而調整的下述式的化合物 [化7]

硫代化合物A5：依照日本專利2708607號公報的實施例1的記載而製備的下述式的化合物 [化8]

As the compound (A), the following thio compounds A1 to A5 were used. Thio compound A1: a compound of the following formula prepared according to the description of Example 2 of JP 7-91262 A

Thio compound A2: a compound of the following formula prepared according to the description of Example 3 of Japanese Patent No. 2708607 [Chem. 5]

Thio compound A3: a compound of the following formula prepared according to the description of Synthesis Example 6 of Japanese Patent Laid-Open No. 9-324023 [Chem. 6]

Thio compound A4: Except for replacing 25.0 parts (0.10 mol) of 4,4'-thiobis-benzenethiol in Example 1 of Japanese Patent No. 2708607 with 24.8 parts (0.20 mol) of benzyl thiol, A compound of the following formula adjusted by the same operation as Example 1 of Japanese Patent No. 2708607 [Chem. 7]

Thio compound A5: a compound of the following formula prepared according to the description of Example 1 of Japanese Patent No. 2708607 [Chem. 8]

As the compound (B), the following (meth)acrylic compounds B1 to B4 were used. (Meth)acrylic compound B1: Ethoxylated o-phenylphenol acrylate, product name NK Ester (NK Ester) A-LEN-10, manufactured by Shin-Nakamura Chemical Industry Co., Ltd. (Meth)acrylic acid compound B2: m-phenoxybenzyl acrylate, product name Light Acrylate (Light Acrylate) POB-A, manufactured by Kyeisha Chemical Co., Ltd. (Meth)acrylic acid compound B3: Benzyl acrylate, product name Biscoat #160, manufactured by Kyeisha Chemical Co., Ltd. (Meth)acrylic acid compound B4: 1,9-nonanediol diacrylate, product name Light Acrylate 1,9ND-A, manufactured by Kyōeisha Chemical Co., Ltd.

As a heat stabilizer, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (trade name Adekastab AO-60, Adi Section (ADEKA) company manufacture). As a photoradical initiator, 2,4,6-trimethylbenzyldiphenylphosphine oxide (product name Omnirad TPO H, manufactured by IGM Resins) was used.

Each component was prepared so that it might become the preparation composition shown in Table 1, and the liquid sealing material was obtained. The unit of the compounding composition of compound (A) and compound (B) in Table 1 is the part by mass of compound (A) or compound (B) with respect to 100 parts by mass of the total of compound (A) and compound (B) . In addition, the unit of the preparation composition of the thermal stabilizer and the photo-radical initiator in Table 1 is the mass % with respect to the whole composition of a sealing material.

The physical properties of the obtained sealing material were measured by the following methods. The measurement results are shown in Table 1.

(viscosity) The viscosity of the obtained sealing material was measured under the conditions of 25° C. and 20 rpm using an E-type viscometer (LV DV-II+Pro, manufactured by BROOKFIELD). Evaluation was performed according to the following criteria. The results are shown in Table 1. ○: 5 mPa·s～50 mPa·s ×: Less than 5 mPa·s or more than 50 mPa·s

(Refractive index) The refractive index of the cured film obtained by hardening the obtained sealing material was evaluated by the following method. Using a 100 μm-thick Teflon (registered trademark) sheet as a mold frame, the mold frame was placed on a transparent polyethylene terephthalate (PET) film, and the sealing material obtained by the method was poured into it, A transparent PET film was placed thereon, the sealing material was sandwiched between two transparent PET films, and a UV-LED with a wavelength of 395 nm was used under an illumination intensity of 1000 mW/cm ² and a cumulative light intensity of 1500 mJ/cm ² . By making it harden under conditions, a hardened film is obtained. About the obtained cured film, the refractive index of the cured film under d rays (wavelength: 587.6 nm) at room temperature (25°C) was measured with an Abbe refractometer (manufactured by Atago, DR-M4). (nd). Evaluation was performed according to the following criteria. The results are shown in Table 1. ○: 1.60 or more ×: less than 1.60

(Plasma resistance) As the plasma resistance, element damage in the plasma processing step using a parallel-plate type electron cyclotron resonance plasma CVD apparatus was evaluated by the following method. The sealing material obtained by the said method was introduce|transduced into the ink jet cartridge DMC-11610 (manufactured by Fujifilm Dimatix). This ink-jet cartridge was set in an ink-jet device DMP-2831 (manufactured by Fujifilm Dimatix), and after adjusting the ejection state, the thickness after curing was 10 μm, and the thickness was 15 μm. The size of mm × 15 mm is coated on a glass substrate. The obtained coating film was placed in a box adjusted to room temperature (25° C.) with nitrogen flow, left for 5 minutes, and then UV-LED with a wavelength of 395 nm was used at an illuminance of 1000 mW/cm ² and a cumulative light intensity of 1500 mJ/ By irradiating on the conditions of cm ² , a cured film is formed. Using a parallel plate type electron cyclotron resonance plasma CVD apparatus, under the conditions of a power of 100 W and a surface temperature of the cured film of 100°C, an inorganic material film (SiN _x film) with a thickness of 1 μm was vapor-deposited on the surface of the cured film. The obtained sample was put into a constant temperature and humidity tank at 85°C and 85%, and the appearance after 240 hours was observed. Evaluation was performed according to the following criteria. The results are shown in Table 1. ○: Not whitened ×: Whitened

[Table 1] Table 1 Example Comparative example 1 2 3 4 5 6 7 8 9 1 2 3 4 Compound (A) (parts by mass) Thio compound A1 100 95 90 90 90 95 97 70 97 Thio compound A2 5 Thio compound A3 3 Thio compound A4 30 Thio compound A5 3 Compound (B) (parts by mass) (Meth)acrylic compound B1 5 100 (Meth)acrylic compound B2 10 100 (Meth)acrylic compound B3 10 100 (Meth)acrylic compound B4 10 100 Heat stabilizer (mass % relative to the entire composition of the sealing material) 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Photoradical initiator (mass % relative to the entire composition of the sealing material) 3 3 3 3 3 3 3 3 3 3 3 3 3 viscosity (mPa s) twenty four 30 twenty two 18 20 32 40 18 45 135 20 3 6 Evaluation ○ ○ ○ ○ ○ ○ ○ ○ ○ × ○ × ○ refractive index (nd) 1.64 1.63 1.63 1.63 1.62 1.64 1.64 1.62 1.65 1.59 1.57 1.52 1.47 Evaluation ○ ○ ○ ○ ○ ○ ○ ○ ○ × × × × Plasma resistance Evaluation ○ ○ ○ ○ ○ ○ ○ ○ ○ × × × ○

As shown in Table 1, the sealing material and its cured product obtained in each example were excellent in the effect of suppressing element damage by plasma irradiation, had a high refractive index, and had a low viscosity suitable for coating.

This application claims priority based on Japanese Patent Application No. 2020-191965 for which it applied on Nov. 18, 2020, the entire disclosure of which is incorporated herein.

10: Organic EL display element 21: The first inorganic material film 22: The first sealing layer 23: The second inorganic material film 24: Second sealing layer 25: Surface protection layer 50: Substrate 100: Organic EL Display Device

FIG. 1 is a cross-sectional view showing a configuration example of an organic EL display device according to an embodiment.

10: Organic EL display elements

21: The first inorganic material film

22: The first sealing layer

23: The second inorganic material film

24: Second sealing layer

25: Surface protection layer

50: Substrate

100: Organic EL Display Device

Claims (10)

A sealing material for an organic electroluminescence display element, comprising a compound (A) having a (meth)acrylic thio group represented by the following general formula (1), [Chem. 1]

[In the general formula (1), R ₁ represents a hydrogen atom or a methyl group, and * represents a bonding position]. The sealing material for organic electroluminescence display elements according to claim 1, wherein the compound (A) is a compound having two or more of the (meth)acrylic thio groups. The sealing material for organic electroluminescence display elements according to claim 1, further comprising a compound (B) having a (meth)acrylic group (except for the compound (A)). The sealing material for organic electroluminescence display elements according to claim 3, wherein the compound (B) is a compound further having a substituted aromatic group. The sealing material for organic electroluminescence display elements according to claim 1, wherein the viscosity at 25°C and 20 rpm measured by an E-type viscometer is 5 mPa·s or more and 50 mPa·s or less. The sealing material for organic electroluminescence display elements according to claim 1 is used for coating by an inkjet method. The sealing material for an organic electroluminescence display element according to claim 1, wherein the organic electroluminescence display element, the first inorganic material film, the sealing layer, and the second inorganic material film are laminated in this order. In a display device, it is used for the formation of the sealing layer. The sealing material for organic electroluminescence display elements according to claim 1 is used as the filling material in a sealing structure using a barrier material and a filling material. A cured product obtained by curing the sealing material for an organic electroluminescence display element according to claim 1. An organic electroluminescence display device, comprising: organic electroluminescent display elements; and a sealing layer covering the organic electroluminescence display element, The said sealing layer contains the hardened|cured material as described in Claim 9.

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