CN116438214A

CN116438214A - Sealing material for organic EL display element, cured product thereof, and organic EL display device

Info

Publication number: CN116438214A
Application number: CN202180071449.5A
Authority: CN
Inventors: 富田裕介
Original assignee: Mitsui Chemicals Inc
Current assignee: Mitsui Chemicals Inc
Priority date: 2020-11-18
Filing date: 2021-11-12
Publication date: 2023-07-14
Also published as: WO2022107692A1; JPWO2022107692A1; TW202221098A; KR20230066098A; JP7493058B2

Abstract

A sealing material for an organic EL display element, which contains a compound (A) having a (meth) acryloylthio group represented by the following general formula (1). [ in the above general formula (1), R ₁ 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

Technical Field

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

Background

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

Organic EL display elements are used for displays, lighting devices, and the like because of low power consumption. Since organic EL display elements are susceptible to deterioration due to moisture and oxygen in the atmosphere, they are used by sealing with various sealing members, and it is desired to improve the durability of moisture and oxygen of various sealing members for practical use.

As a sealing method of the organic EL display element, a method of alternately laminating and sealing an inorganic material and an organic material is given. For example, a method is used in which an inorganic material film of layer 1 is coated on an element, a sealing layer is formed thereon, and an inorganic material film of layer 2 is further coated thereon.

Since these inorganic material films have a high refractive index, the sealing layer in contact with the inorganic material films is required to have a high refractive index in order to suppress light reflection at the interface with the inorganic material films.

Here, as a method of coating the sealing layer with the inorganic material film, for example, a method of forming an inorganic material film composed of silicon nitride or silicon oxide by vapor deposition is mentioned. Examples of the vapor deposition method include a sputtering method and an electron cyclotron resonance plasma CVD method.

Since the surface of the sealing layer is exposed to plasma during vapor deposition, plasma resistance, that is, resistance to deterioration due to plasma treatment or the like is also required for the sealing layer.

Patent document 1 describes a composition for sealing an organic light-emitting element, which contains 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 containing a thioepoxy resin obtained by polymerizing a fluorene derivative containing a thioepoxy group and a dithiol compound.

Prior art literature

Patent literature

Patent document 1: japanese patent application laid-open No. 2019-537217

Patent document 2: japanese patent laid-open publication No. 2014-229496

Patent document 3: japanese patent laid-open publication No. 2019-172880

Disclosure of Invention

Problems to be solved by the invention

As described above, in order to suppress light reflection generated at the interface with the inorganic material film, a cured product of the sealing material of the organic EL display device is required to have a high refractive index. In this regard, the cured products of the resin compositions described in patent documents 1 and 2 have refractive indices as low as less than 1.60, and there is room for improvement.

In addition, the resin composition of patent document 2 may have low plasma resistance depending on the type of the (meth) acrylate compound.

Further, the resin composition described in patent document 3 has a high viscosity, and therefore there is room for improvement in the coatability during screen printing and ink jet.

The present invention has been made in view of the descriptions of these patent documents, and provides a sealing material for an organic EL display element which is excellent in balance among viscosity, plasma resistance, and refractive index when a cured product is produced.

Means for solving the problems

According to the present invention, there are provided a sealing material for an organic EL display element, a cured product thereof, and an organic EL display device, which are described below.

[1] A sealing material for an organic EL display element, which contains a compound (A) having a (meth) acryloylthio group represented by the following general formula (1).

[ chemical 1]

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

[2] The sealing material for an organic EL display element according to [1], wherein the compound (A) is a compound having 2 or more (meth) acryloylthio 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) acryloyl group (wherein the above compound (A) is excluded).

[4] The sealing material for an organic EL display element according to item [3], wherein the compound (B) is a compound further having an aromatic group which may be substituted.

[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℃and 20rpm measured by an E-type viscometer is 5 mPas to 50 mPas.

[6] The sealing material for an organic EL display element according to any one of the above [1] to [5], which is used for coating by an ink-jet method.

[7] The sealing material for an organic EL display element according to any one of [1] to [6], which is used for forming the sealing layer in an organic EL display device having a structure in which an organic EL display element, a 1 st inorganic material film, a sealing layer, and a 2 nd inorganic material film are laminated in this order.

[8] The sealing material for an organic EL display element according to any one of the above [1] to [7], wherein the sealing structure using a bank material and a filler is used as the filler.

[9] A cured product obtained by curing the sealing material for an organic EL display element as described in any one of the above [1] to [8 ].

[10] An organic EL display device, comprising:

organic EL display element and method of manufacturing the same

A sealing layer covering the organic EL display element,

the sealing layer contains the cured product of [9 ].

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a sealing material for an organic EL display element having an excellent balance among viscosity, plasma resistance, and refractive index when a cured product is produced can be provided.

Drawings

Fig. 1 is a cross-sectional view showing an example of the structure of an organic EL display device according to the embodiment.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, common symbols are attached to the same constituent elements, and the description thereof is omitted as appropriate. In the present embodiment, 1 kind of each component may be used, or 2 or more kinds may be used in combination. The term "to" representing the numerical range means not less than and not more than, and includes both the upper limit value and the lower limit value.

Sealing Material for organic EL display element

(Compound (A))

In this embodiment, a sealing material for an organic EL display element (hereinafter, also simply referred to as "sealing material" as appropriate) contains a compound (a) having a (meth) acryloylthio group represented by the following general formula (1). The sealing material of the present embodiment is excellent in balance between viscosity, plasma resistance, and refractive index when a cured product is produced.

[ chemical 1]

From the viewpoint of increasing the refractive index of the cured product of the sealing material, the compound (a) is preferably a compound having 2 or more (meth) acryloylthio groups.

The compound (a) is a compound represented by the following general formula (2).

[ chemical 2]

[ in the above general formula (2), R ₁ R has the same meaning as that of formula (1) ₂ Represents an optionally substituted aliphatic group, an optionally substituted alicyclic group, an optionally substituted aliphatic group,An optionally substituted aromatic group or an optionally substituted heterocyclic group, the aliphatic group and the alicyclic group may 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 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and still more preferably 1 to 10 carbon atoms.

In the general formula (2), n is preferably 2 or more 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. The upper limit of n is not limited, and may be, for example, 12 or less, 6 or less, or 3 or less.

In the general formula (2), R is from the viewpoint of increasing the refractive index of the cured product of the sealing material and also from the viewpoint of improving the plasma resistance of the cured product of the sealing material ₂ Preferably an aliphatic group which may be substituted and has a sulfur atom.

The sealing material for an organic EL display element according to the present embodiment may contain only 1 kind of compound (a) or may contain a plurality of kinds of compounds (a).

The sealing material for an organic EL display element of the present embodiment preferably contains a plurality of compounds (a) having different values of n in the general formula (2) from the viewpoint of increasing the refractive index of the cured product of the sealing material and also improving the plasma resistance of the cured product of the sealing material.

The compound of the general formula (2) is produced, for example, from a thiol compound represented by the general formula (3) and a (meth) acryloyl halide by dehalogenation and dehydrogenation.

[ chemical 3]

R ₂ (SH) _n (3)

[ in the above general formula (3), R ₂ And n is each the same as R of the formula (2) ₂ And n is as defined above.]

The thiol compound represented by the general formula (3) may have a hydroxyl group in addition to a mercapto group.

Specific examples of the thiol compound represented by the following general formula (3) are given below. In addition, R in the general formula (2) ₂ Specifically, the following compounds are exemplified.

Among the thiol compounds represented by the general formula (3), as a monothiol compound having 1 thiol group, specifically, examples thereof include methyl mercaptan, ethyl mercaptan, propyl mercaptan, butyl mercaptan, pentyl mercaptan, hexyl mercaptan, heptyl mercaptan, octyl mercaptan, nonyl mercaptan, decyl mercaptan, undecyl mercaptan, dodecyl mercaptan, tridecyl mercaptan, tetradecyl mercaptan, cetyl mercaptan, octadecyl mercaptan, allyl mercaptan, 2-butene-1-mercaptan, 1-butene-4-mercaptan, methallyl mercaptan, 1-pentenyl mercaptan, 2-isopentenyl mercaptan, oleyl mercaptan, cyclopentyl mercaptan, cyclohexyl mercaptan, cyclopentyl methyl mercaptan, cycloheptyl mercaptan, 3-methylcyclopentyl methyl mercaptan, 2-methylcyclohexyl mercaptan, 3-methylcyclohexyl mercaptan, 4-methylcyclohexylthiol, 3-methylcyclohexylmethyl thiol, 1-cyclopentylthiol, 2-cyclohexenylthiol, beta-cyclohexylethyl thiol, 2, 6-tetramethylcyclohexylthiol, epsilon-cyclohexylpentylthiol, cholesteryl thiol, furfuryl thiol, methylfurfuryl thiol, 2-mercaptothiophene, 3-mercaptothiophene, 2-ethyl-3-mercaptothiophene, thiophenol, thiocresol, ethylphenol, 2, 4-thioxylenol, 2, 5-thioxylenol, propylthiophenol, allylthiophenol, 2-allyl-4-methylbenzothiool, phenylthiophenol, chlorophenylthhiol, bromothiophenol, iodothiophenol, nitrophenthiophenol, trinitrothiophenol, dinitrothiophenol, nitrobenzenesulfide, nitrobromothiophenol, nitrochlorobenzenesulfide, methylsulfonylbenzenesulfide, phenylthiol, benzylthiol, nitrobenzyl thiol, alpha-phenylethylthiol, beta-phenylethylthiol, alpha-phenylpropyl thiol, gamma-phenylpropyl thiol, beta-phenyl-isopropyl thiol, D-beta-phenylbutyl thiol, epsilon-phenylpentyl thiol, alpha, beta-diphenylethyl thiol, methylbenzyl thiol, 2-nitro-p-tolyl thiol, alpha- (o-tolyl) benzyl thiol, alpha- (p-tolyl) benzyl thiol, chlorobenzyl thiol, dichlorobenzyl thiol, bromobenzyl thiol, alpha-phenyl-p-chlorobenzyl thiol, 3-hydroxy-5-methylbenzyl thiol, cinnamyl thiol, beta-gamma-diphenylallyl thiol, 4' -dichlorobenzyl thiol, triphenylmethyl thiol, alpha-thio naphthol, beta-thio naphthol, 4-chloro-alpha-thio naphthol, 4-bromo-alpha-thio naphthol, 1-nitro-alpha-thio-4-nitro-alpha-thio, etc.

Among thiol compounds represented by the general formula (3), as a polythiol compound having 2 or more thiol groups, specific examples thereof include:

methyl dithiol, 1, 2-ethanedithiol, 1-propanedithiol, 1, 2-propanedithiol, 1, 3-propanedithiol, 2-propanedithiol, 1, 6-hexanedithiol, 1,2, 3-propanetrithiol, 1-cyclohexanedithiol, 1, 2-cyclohexanedithiol, 2-dimethylpropane-1, 3-dithiol 3, 4-Dimethoxybutane-1, 2-dithiol, 2-methylcyclohexane-2, 3-dithiol, bicyclo [2, 1] hept-exo-cis-2, 3-dithiol, 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-mercaptoacetate), diethylene glycol bis (2-mercaptoacetate), diethylene glycol bis (3-mercaptopropionate), 1, 2-dimercaptopropylmethyl ether, 2, 3-dimercaptopropylmethyl ether, 2-bis (mercaptomethyl) -1, 3-propanedithiol, bis (2-mercaptoethyl) ether, ethylene glycol bis (2-mercaptoacetate), ethylene glycol bis (3-mercaptopropionate), trimethylolpropane bis (2-mercaptoacetate), trimethylolpropane bis (3-mercaptopropionate), pentaerythritol tetrakis (2-mercaptoacetate), aliphatic polythiols such as pentaerythritol tetrakis (3-mercaptopropionate), halogen-substituted aliphatic polythiols such as chlorine substituents and bromine substituents thereof;

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 (mercaptoethyleneoxy) benzene, 1, 3-bis (mercaptoethyleneoxy) benzene, 1, 4-bis (mercaptoethyleneoxy) benzene, 1,2, 3-trismercaptobenzene, 1,2, 4-trismercaptobenzene 1,3, 5-trismercaptobenzene, 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 (mercaptoethyleneoxy) benzene, 1,2, 4-tris (mercaptoethyleneoxy) benzene, 1,3, 5-tris (mercaptoethyleneoxy) benzene, 1,2,3, 4-tetramercaptobenzene, 1,2,3, 5-tetramercaptobenzene, 1,2,4, 5-tetramercaptobenzene, 1,2,3, 4-tetrakis (mercaptomethyl) 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 (mercaptoethyleneoxy) benzene, 1,2,3, 5-tetrakis (mercaptoethyleneoxy) benzene, 1,2,4, 5-tetrakis (mercaptoethyleneoxy) benzene, 2 '-dimercaptobiphenyl aromatic polythiols such as 4,4' -thiodiphenyl mercaptan, 4 '-dimercaptobiphenyl, 4' -dimercaptobenzene, 2, 5-toluene dithiol, 3, 4-toluene dithiol, 1, 4-naphthalene dithiol, 1, 5-naphthalene dithiol, 2, 6-naphthalene dithiol, 2, 7-naphthalene dithiol, 2, 4-dimethyl-1, 3-dithiol, 4, 5-dimethyl-1, 3-dithiol, 9, 10-anthracene dimethanethiol, 1, 3-bis (p-methoxyphenyl) propane-2, 2-dithiol, 1, 3-diphenylpropane-2, 2-dithiol, phenyl methane-1, 1-dithiol, 2, 4-bis (p-mercaptophenyl) pentane, and bis (4-mercaptophenyl) sulfide;

Halogen-substituted aromatic polythiols such as chlorine substituents of aromatic polythiols, e.g., 2, 5-dichlorobenzene-1, 3-dithiol, 1, 3-bis (p-chlorophenyl) propane-2, 2-dithiol, 3,4, 5-tribromo-1, 2-dimercaptobenzene, 2,3,4, 6-tetrachloro-1, 5-bis (mercaptomethyl) benzene, and bromine substituents of aromatic polythiols;

heterocyclic-containing polythiols such as 2-methylamino-4, 6-dithiol-s-triazine, 2-ethylamino-4, 6-dithiol-s-triazine, 2-amino-4, 6-dithiol-s-triazine, 2-morpholino-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-thiophenedichiol, bismuth-test thiol (biskuthiol);

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 (mercaptomethylthiothio) benzene, 1,2,3, 5-tetrakis (mercaptomethylthiothio) benzene, 1,2,4, 5-tetrakis (mercaptomethylthio) benzene, 1,2, 4-tetrakis (mercaptoethylthio) benzene, 1,2, 5-tetrakis (mercaptoethyl) benzene, a polynuclear aromatic thio compound of 1,2,3, 5-tetrakis (mercaptoethylthio) benzene, etc.;

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 (mercaptomethylthiomethyl) methane, tetrakis (2-mercaptoethylthio) methyl) methane, tetrakis (3-mercaptopropyl thio) methane, bis (2, 3-dimercapto-methyl) sulfide, bis (2, 3-dimercapto-ethyl) sulfide, bis (dimercapto) sulfide, bis (4-dimercapto) sulfide, bis (dimercapto) ethyl sulfide, bis (4-mercaptoethyl) sulfide, bis (dimercapto) aliphatic sulfide, bis (4-mercaptoethyl) sulfide, bis (mercaptopropyl) sulfide, bis (dimercapto) sulfide, bis (4-mercaptoethyl) sulfide, bis (4-mercaptomethyl) and the like;

hydroxymethyl thioether bis (2-mercaptoacetate), hydroxymethyl thioether bis (3-mercaptopropionate), hydroxyethyl thioether bis (2-mercaptoacetate), hydroxyethyl thioether bis (3-mercaptopropionate), hydroxypropyl thioether bis (2-mercaptoacetate), hydroxypropyl thioether bis (3-mercaptopropionate), hydroxymethyl disulfide bis (2-mercaptoacetate), hydroxymethyl disulfide bis (3-mercaptopropionate), hydroxyethyl disulfide bis (2-mercaptoacetate), hydroxyethyl disulfide bis (3-mercaptopropionate), 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), thiodiglycol bis (2-mercaptoacetate), diethyl dithiopropionate), diethyl dithiobutyrate bis (2-mercaptoethyl dithiopropionate), diethyl dithiobutyrate, aliphatic polythiol esters such as bis (2-mercaptoethyl) 4, 4-dithiodibutyrate, bis (2, 3-dimercaptopropyl) thiodiglycolate, bis (2, 3-dimercaptopropyl) thiodipropionate, bis (2, 3-dimercaptopropyl) dithioglycolate, and bis (2, 3-dimercaptopropyl) dithiodipropionate;

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 (thioglycolate), pentaerythritol penta (3-mercaptopropionate), hydroxymethyl-tris (mercaptoethylthiomethyl) methane, 1-hydroxyethylthio-3-mercaptoethylthio benzene, 4-hydroxy-4' -mercaptodiphenyl sulfone, 2- (2-mercaptoethylthio) ethanol, dihydroxyethylthio-mono (3-mercaptopropionate), dimercaptoethane), mono (salicyl) ethyl, tris (2-mercaptoethane), bis (2-mercaptoethane) 2-bis (mercaptomethyl) thio) methane, 3,3' -thiobis (2- ((2-mercaptoethyl) thio) propane-1-thiol) and the like.

Further, halogen substituents such as chlorine substituents and bromine substituents can be mentioned.

(Compound (B))

The sealing material for an organic EL display element of the present embodiment may further contain a compound (B). The compound (B) is a (meth) acryl-containing compound (excluding the above-described compound (a)).

Here, in the present specification, (meth) acryl means at least one of acryl and methacryl. Further, (meth) acrylic refers to at least one of acrylic acid or methacrylic acid. Further, (meth) acrylate refers to at least one of acrylate and methacrylate.

Specific examples of the (meth) acrylic compound having a (meth) acryloyl group include 1-functional mono (meth) acrylic compound, 2-functional di (meth) acrylic compound, and 3-functional or more polyfunctional (meth) acrylic compound.

Specific examples of the mono (meth) acrylic compound include isobornyl (meth) acrylate, dicyclohexyl (meth) acrylate, 3, 5-trimethylcyclohexyl (meth) acrylate, 4-t-butylcyclohexyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, isooctyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, methoxytriethylene glycol (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethoxyethyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxyxylyl (meth) acrylate, ethyldiethylene glycol (meth) acrylate, cyclic trimethylolpropane formal mono (meth) acrylate, imide (meth) acrylate, isopropyl (meth) acrylate, ethoxylated (meth) acrylate, and ethoxylated ethyl (meth) acrylate, omega-carboxypolycaprolactone mono (meth) acrylate, cyclohexyl (meth) acrylate, 2- (2-ethoxyethoxy) ethyl (meth) acrylate, stearyl (meth) acrylate, diethylene glycol monobutyl ether (meth) acrylate, lauryl (meth) acrylate, isodecyl (meth) acrylate, isooctyl (meth) acrylate, octyl/decyl (meth) acrylate, tridecyl (meth) acrylate, caprolactone (meth) acrylate, ethoxylated (4) nonylphenol (meth) acrylate, methoxypolyethylene glycol (350) mono (meth) acrylate, methoxypolyethylene glycol (550) mono (meth) acrylate, phenoxyethyl (meth) acrylate, cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, benzyl (meth) acrylate, methylphenoxyethyl (meth) acrylate, caprolactone-modified tetrahydrofurfuryl (meth) acrylate, tribromophenyl (meth) acrylate, ethoxylated tribromophenyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, ethylene oxide-2-phenoxyethyl (meth) acrylate, ethylene oxide addition of (meth) acrylate, 2-phenoxyethyl (meth) acrylate addition of, phenoxydiglycol (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 3-methacryloxymethyl cyclohexene oxide, 3- (meth) acryloxymethyl cyclohexene oxide, and the like.

Specific product names and sources of the mono (meth) acrylic compounds include ethoxylated ortho-phenylphenol acrylate (NK ester A-LEN-10, manufactured by Xinzhou chemical industry Co., ltd.), and m-phenoxybenzyl acrylate (LIGHT ACRYLATE POB-A, manufactured by Kagaku chemical Co., ltd.).

Specific examples of the di (meth) acrylic compound include di (meth) acrylate of diol, di (meth) acrylate of (poly) alkylene glycol, and the like.

Specific product names and sources of the di (meth) acrylic compounds include 1, 6-hexanediol diacrylate (NK ester a-HD-N, manufactured by new middle village chemical industry company; LIGHT ACRYLATE 1,6HX-A, manufactured by Kyowa chemical Co., ltd.), 1, 9-nonanediol diacrylate (NK ester A-NOD-N, manufactured by Kyowa chemical Co., ltd.), 1, 10-decanediol diacrylate (NK ester A-DOD-N, manufactured by Kyowa chemical Co., ltd.), neopentyl glycol diacrylate (NK ester A-NPG, manufactured by Kyowa chemical Co., ltd.), ethylene glycol diacrylate (SR 206NS, manufactured by Arkema Co., ltd.), polyethylene glycol diacrylate (NK ester A-400, manufactured by Kyowa chemical Co., ltd.), polypropylene glycol diacrylate (NK ester APG-400, manufactured by Kyowa chemical Co., ltd.), tricyclodecane dimethanol diacrylate (alias: dimethylol-tricyclodecane diacrylate) (NK ester A-DCP, manufactured by Kyowa chemical Co., ltd.), LIGHT ACRYLATE DCP-A, manufactured by Kyowa chemical Co., ltd.), 1, 3-dimethylbutylene acrylate (BD, manufactured by Kyowa chemical Co., ltd.), and 1, 3-dimethylbutylene diacrylate (BD, manufactured by Kyowa chemical Co., ltd., from Kyowa chemical Co., ltd.), and 1, 4-butanediol diacrylate (manufactured by Kyowa chemical Co., ltd.), 1, 6-hexanediol dimethacrylate (NK ester HD-N, manufactured by New York chemical industry Co., ltd.), 1, 9-nonanediol dimethacrylate (NK ester NOD-N, manufactured by New York chemical industry Co., ltd.), 1, 10-decanediol dimethacrylate (NK ester DOD-N, manufactured by New York chemical industry Co., ltd.), 1, 12-dodecanediol diacrylate (SR 262, manufactured by Sartomer Co., ltd.) neopentyl glycol dimethacrylate (NK ester NPG, manufactured by New York chemical industry Co., ltd.), and the like.

Specific product names and acquisition sources of the polyfunctional (meth) acrylic compounds include:

3-functional (meth) acrylic compounds such as trimethylolpropane triacrylate (NK ester A-TMPT, manufactured by New Yoghurt chemical industry Co., ltd.; LIGHT ACRYLATE TMP-A, manufactured by Kyowa chemical industry Co., ltd.), ethoxylated trimethylolpropane triacrylate (NK ester A-TMPT-EO, manufactured by New Yoghurt chemical industry Co., ltd.), ethoxylated glycerol triacrylate (NK ester A-GLY-6E, manufactured by New Yoghurt chemical industry Co., ltd.), propoxylated glycerol triacrylate (NK ester A-GLY-3P, manufactured by New Yoghurt chemical industry Co., ltd.);

4-functional (meth) acrylic compounds such as pentaerythritol tetraacrylate (NK ester A-TMMT, manufactured by New Yoghurt chemical industry Co., ltd.), ethoxylated pentaerythritol tetraacrylate (NK ester ATM-4E, manufactured by New Yoghurt chemical industry Co., ltd.), and ditrimethylolpropane tetraacrylate (NK ester AD-TMP-L, manufactured by New Yoghurt chemical industry Co., ltd.);

5-functional (meth) acrylic compounds such as dipentaerythritol pentaacrylate (M-402, manufactured by Toyama Synthesis Co., ltd.);

6-functional (meth) acrylic compounds such as dipentaerythritol hexaacrylate (GM 66G0H, manufactured by national chemical company); etc.

From the viewpoint of increasing the refractive index of the cured product of the sealing material, the compound (B) is preferably a compound further having an aromatic group which may be substituted. Specific examples of the optionally substituted aromatic group in the compound (B) include the optionally substituted aromatic groups among the groups derived from the thiol compound represented by the general formula (3).

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 mass% or more, more preferably 90 mass% or more, still more preferably 95 mass% or more, and still more preferably 99 mass% or more, with respect to the entire composition of the sealing material of the present embodiment.

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, relative to 100 parts by mass of the total of the compound (a) and the compound (B).

The amount of the compound (a) may be, for example, 70 parts by mass or more and 100 parts by mass or less, or 80 parts by mass or more and 100 parts by mass or less, based on 100 parts by mass of the total of the compound (a) and the compound (B).

The amount of the compound (B) is preferably 0 to 50 parts by mass, more preferably 0 to 40 parts by mass, based on 100 parts by mass of the total of the compound (a) and the compound (B).

The amount of the compound (B) may be, for example, 0 to 30 parts by mass, for example, 0 to 20 parts by mass, based on 100 parts by mass of the total of the compound (a) and the compound (B).

(polymerization initiator)

The sealing material of the present embodiment may further include 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 of ultraviolet rays or visible rays, that is, a photopolymerization initiator.

Examples of the photopolymerization initiator include an acylphosphine oxide initiator, an oxyphenyl acetate initiator, a benzoic acid initiator, and a hydroxyphenylketone initiator.

As a specific example of the photopolymerization initiator, examples include benzophenone, michler's ketone, 4' -bis (diethylamino) benzophenone, xanthone, thioxanthone, isopropylxanthone, 2, 4-diethylthioxanthone, 2-ethylanthraquinone, acetophenone, 2-hydroxy-2-methyl-4 ' -isopropylbenzone, isopropylbenzoin ether, isobutylbenzoin ether, benzoin ether, and 2, 2-diethoxyacetophenone, 2-dimethoxy-2-phenylacetophenone, camphorquinone, benzanthrone, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, 4' -di (t-butylperoxycarbonyl) benzophenone, 3,4' -tri (t-butylperoxycarbonyl) benzophenone, 3',4,4' -tetra (tert-butylperoxycarbonyl) benzophenone, 3',4' -tetra (tert-hexylperoxycarbonyl) benzophenone, 3' -bis (methoxycarbonyl) -4,4' -bis (tert-butylperoxycarbonyl) benzophenone, 3,4' -bis (methoxycarbonyl) -4,3' -bis (tert-butylperoxycarbonyl) benzophenone, 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' -dimethoxystyryl) -4, 6-bis (trichloromethyl) -s-triazine, 2- (2 ' -methoxystyryl) -4, 6-bis (trichloromethyl) -s-triazine, 2- (4 ' -pentyloxystyryl) -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 (trichloromethyl) -5- (4' -methoxyphenyl) -s-triazine, 2- (p-dimethylaminostyryl) benzo

Oxazole, 2- (p-dimethylaminostyryl) benzothiazole, 2-mercaptobenzothiazole, 3 '-carbonylbis (7-diethylaminocoumarin), 2- (o-chlorophenyl) -4,4',5 '-tetraphenyl-1, 2' -biimidazole, 2 '-bis (2-chlorophenyl) -4,4',5 '-tetrakis (4-ethoxycarbonylphenyl) -1,2' -biimidazole,2,2 '-bis (2, 4-dichlorophenyl) -4,4',5 '-tetraphenyl-1, 2' -biimidazole, 2 '-bis (2, 4-dibromophenyl) -4,4',5 '-tetraphenyl-1, 2' -biimidazole, 2 '-bis (2, 4, 6-trichlorophenyl) -4,4',5 '-tetraphenyl-1, 2' -biimidazole, 3- (2-methyl-2-dimethylaminopropionyl) carbazole, 3, 6-bis (2-methyl-2-morpholinopropionyl) -9-n-dodecylcarbazole, bis (. Eta.5-2, 4-cyclopenta-1-yl) -bis (2, 6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1- [4- (2-hydroxyethoxy) -phenyl ketone]-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-morpholinophenyl) -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 benzoate, bis (2, 4, 6-trimethylbenzoyl) phenylphosphine oxide, 2,4, 6-trimethylbenzoyl diphenylphosphine oxide, 2,4, 6-trimethylbenzoyl diphenylphosphinate, 1- [4- (phenylthio) phenyl ]]-1, 2-octanedione 2- (O-benzoyl oxime), 1- [ 9-ethyl-6- (2-methylbenzoyl) -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 one or more compounds selected from the group consisting of 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-dimethoxy-2-phenylacetophenone, 2- [ 2-oxo-2-phenyl-acetoxy-ethoxy ] -ethyl ester, 2- [ 2-hydroxy-ethoxy ] -ethyl ester of oxy-phenyl-acetic acid, methyl benzoate, bis (2, 4, 6-trimethylbenzoyl) phenylphosphine oxide, 2,4, 6-trimethylbenzoyl diphenylphosphine oxide (TPO), 2,4, 6-trimethylbenzoyl diphenylphosphinate.

Specific product names and acquisition sources of photopolymerization initiators include Irgacure184, irgacure651, irgacure127, irgacure1173, irgacure500, irgacure2959, irgacure754, irgacureMBF, irgacureTPO (above, manufactured by BASF corporation), omnirad TPO H (manufactured by IGM Resins corporation), and the like.

From the viewpoint of improving the curability of the sealing material, the content of the polymerization initiator is preferably 0.1 mass% or more, more preferably 0.5 mass% or more, still more preferably 1 mass% or more, and still more preferably 2 mass% or more, relative to the entire composition of the sealing material.

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

(other Components)

The sealing material of the present embodiment may contain, as components (other components) other than the above, 1 or 2 or more components selected from the group consisting of a thickener, a filler, a curing accelerator, a plasticizer, a surfactant, a heat stabilizer, an antioxidant, a flame retardant, an antistatic agent, an antifoaming agent, a leveling agent, and an ultraviolet absorber.

The content of the other component is preferably 5% by mass or less, more preferably 1% by mass or less, relative to the entire composition of the sealing material.

The sealing material preferably contains a heat stabilizer from the viewpoint of improving the thermal stability of the sealing material.

As the heat stabilizer, a hindered phenol compound can be used.

Examples of the hindered phenol compound include dibutylhydroxytoluene (referred to as "2, 6-bis (1, 1-dimethylethyl) -4-methylphenol") (referred to as "BHT" and manufactured by Wako pure chemical industries, ltd.), 3, 5-di-t-butyl-4-hydroxytoluene, pentaerythritol tetrakis [3- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate ] (referred to as "IRGANOX 1010", manufactured by BASF, manufactured by ADEKASTAB AO-60, manufactured by ADEKA), and octadecyl-3- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate (referred to as "IRGANOX 1076", manufactured by BASF).

In view of further improving the thermal stability of the sealing material, the sealing material preferably contains at least one of dibutylhydroxytoluene and pentaerythritol tetrakis [3- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate ] as a heat stabilizer.

As the antioxidant, a phosphorus-based antioxidant can be used.

Examples of the phosphorus antioxidant include phosphites, such as 2, 2-methylenebis (4, 6-di-t-butylphenyl) octyl phosphite (product name ADEKASTAB HP-10, product name ADEKA), and tris (2, 4-di-t-butylphenyl) phosphite (product name IRGAFOS168, product name BASF).

(Properties of sealing Material)

The properties of the sealing material of the present embodiment are not limited, and are preferably liquid from the viewpoint of being suitable for application by an inkjet method or the like.

In the embodiment, the sealing material is preferably a sealing material for coating, and more preferably a sealing material for coating by an inkjet method, from the viewpoint of stably forming the sealing layer.

From the viewpoint of improving the ink jet ejectability, the viscosity of the sealing material obtained by measurement at 25℃and 20rpm using an E-type viscometer is preferably 5 mPas or more, more preferably 8 mPas or more, and still more preferably 10 mPas or more.

In addition, from the viewpoint of improving the ink-jet ejectability, the viscosity of the sealing material is preferably 50mpa·s or less, more preferably 40mpa·s or less, and further preferably 30mpa·s or less.

(method for producing sealing Material)

A method for producing the sealing material is described. The method for producing the sealing material is not limited, and includes: for example, the compound (a) is mixed with an appropriate compound (B) and other components, for example, various additives, which are added as needed.

Examples of the method of mixing the components include a method of uniformly kneading the components by using or using a known various kneading machine such as a planetary stirring device, a homogenizing and dispersing device, a universal mixer, a Banbury mixer, a kneader, a twin roll mill, a triple roll mill, an extruder, etc., under normal temperature or under heating, under normal pressure, under reduced pressure, under inactive gas flow, etc.

< cured object >)

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 cured product of the sealing material of the present embodiment is obtained by applying the sealing material of the present embodiment to a substrate and curing the same. The application may be performed by a known method such as an inkjet method, screen printing, or dispenser application.

The sealing material applied to the substrate can be dried and cured. The method of drying the sealing material can be performed by heating to a temperature at which the compound (a) does not polymerize, for example. The shape of the cured product obtained by curing the sealing material is not limited, and may be, for example, a film shape or a layer shape.

In addition, the sealing material applied to the base material may be photo-cured. Examples of the method for photocuring the sealing material include a method in which light is irradiated from a light source such as a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, an excimer laser, a chemical lamp, a black light lamp, a microwave-excited mercury lamp, a metal halide lamp, a sodium lamp, a halogen lamp, a xenon lamp, an LED lamp such as a UV-LED, a fluorescent lamp, sunlight, or an electron beam irradiation device to cure the sealing material.

The refractive index (nd) of the cured product of the sealing material of the present embodiment in d-rays (wavelength 587.6 nm) at room temperature (25 ℃) is preferably 1.60 or more, more preferably 1.61 or more, further preferably 1.62 or more, further preferably 1.63 or more, further preferably 1.64 or more, further preferably 1.65 or more. The upper limit of the refractive index is not limited, and may be, for example, 2.00 or less, 1.90 or less, or 1.80 or less. The refractive index of the cured sealing material can be measured by an abbe refractometer.

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

< organic EL display device >)

The organic EL display device of the present embodiment includes: an organic EL display element, and a sealing layer containing a cured product of the sealing material of the present embodiment. By providing the sealing layer, the organic EL display element disposed on the substrate is sealed by the sealing layer, so that 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 may be coated with an inorganic material film. The organic EL display element disposed on the substrate may be coated with an inorganic material film in advance before being sealed with the sealing layer.

Specifically, in the organic EL display device having a structure in which the organic EL display element, the 1 st inorganic material film, the sealing layer, and the 2 nd inorganic material film are stacked in this order, the sealing material of the present embodiment is used to form the sealing layer.

Fig. 1 is a cross-sectional view showing an example of the structure of an organic EL display device according to this 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 1 st inorganic material film 21.

The organic EL display element 10 covered with the 1 st inorganic material film 21 is sealed with the 1 st sealing layer 22.

The surface of the 1 st sealing layer 22 is further covered with the 2 nd inorganic material film 23.

The 1 st sealing layer 22 covered with the 2 nd inorganic material film 23 is further sealed by the 2 nd sealing layer 24.

A surface protective layer 25 is provided on the surface of the 2 nd seal layer 24.

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

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

Examples of the inorganic material constituting the 1 st inorganic material film 21 and the 2 nd inorganic material film 23 include silicon nitride (SiN _x ) Silicon oxide (SiO) _x ) Alumina (Al) ₂ O ₃ ) Etc. The inorganic material film may be 1 layer or a laminate of a plurality of layers.

As a coating method using the 1 st inorganic material film 21 and the 2 nd inorganic material film 23, for example, in the case where the inorganic material film is formed of silicon nitride or silicon oxide, a sputtering method, an electron cyclotron resonance plasma CVD method, or the like can be given.

The sputtering method can be performed at room temperature under a power of 50 to 1000W and a pressure of 0.001 to 0.1 torr, for example, using a single gas or a mixed gas such as argon or nitrogen as a carrier gas.

For example, siH can be used in the electron cyclotron resonance plasma CVD method ₄ With O ₂ Is (are) mixed gas or SiH ₄ And N ₂ The mixed gas is carried out under the conditions of the temperature of 30-100 ℃, the pressure of 10 mTorr-1 Torr, the frequency of 2.45GHz and the electric power of 10-1000W.

Since the sealing layer of the present embodiment has excellent plasma resistance, even when an inorganic material film is formed on the surface thereof by plasma treatment such as electron cyclotron resonance plasma CVD, the resin layer is hardly degraded, and damage to the organic EL light-emitting element can be suppressed.

The thicknesses of the 1 st inorganic material film 21 and the 2 nd inorganic material film 23 are not limited, but are, for example, 0.01 to 10 μm, preferably 0.1 to 5 μm, from the viewpoint of improving barrier properties.

As a method for obtaining the sealing layer, a method of applying a sealing material and curing the sealing material and the like can be given. As a method of coating, an inkjet method can be used. The sealing material can be applied in a planar form by a method such as screen printing, dispenser application, inkjet printing, slot die coating, or spray coating.

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

As a method of sealing the organic EL display element, there is a method of forming a bank around the organic EL display element with a curable resin (bank material) having a high viscosity, and injecting a curable resin (filler) having a low viscosity into the bank to cure the same. In the sealing structure using such a dam material and a filler, the filler according to the present embodiment can be used as the filler. The sealing material of the present embodiment has a reduced viscosity and excellent fluidity, and therefore can be suitably used as a filler.

Examples

The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited thereto.

(production of sealing Material)

First, materials used in the following examples are shown.

As the compound (A), the following thio compounds A1 to A5 were used.

Thio compound A1: a compound of the following formula, which is prepared as described in example 2 of Japanese patent publication No. 7-91262

[ chemical 4]

Thio compound A2: a compound of the formula prepared as described in example 3 of Japanese patent No. 2708607

[ chemical 5]

/>

Thio compound A3: a compound of the following formula, which is prepared as described in Synthesis example 6 of Japanese patent application laid-open No. 9-324023

Thio compound A4: a compound of the following formula was prepared in the same manner as in example 1 of Japanese patent No. 2708607, except that 25.0 parts (0.10 mol) of 4,4' -thiobis-phenylthiol in example 1 of Japanese patent No. 2708607 was replaced with 24.8 parts (0.20 mol) of benzylthiol

[ chemical 7]

Thio compound A5: a compound of the formula prepared as described in example 1 of Japanese patent No. 2708607

[ chemical 8]

As the compound (B), the following (meth) acrylic compounds B1 to B4 are used.

(meth) acrylic compound B1: ethoxylated o-phenylphenol acrylic acid ester, product name NK ester A-LEN-10, manufactured by Xinzhongcun chemical industry Co., ltd

(meth) acrylic compound B2: metase:Sub>A-phenoxybenzyl acrylate, product name LIGHT ACRYLATE POB-A, manufactured by Co-Rong chemical Co., ltd

(meth) acrylic compound B3: benzyl acrylate, product name VISCOAT #160, manufactured by Co-Rong chemical Co., ltd

(meth) acrylic compound B4:1, 9-nonanediol diacrylate, product name LIGHT ACRYLATE, 9-ND-A, manufactured by Co., ltd

As the heat stabilizer, pentaerythritol tetrakis [3- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate ] (product name ADEKASTAB AO-60, manufactured by ADEKA Co.). As the photo radical initiator, 2,4, 6-trimethylbenzoyl diphenyl phosphine oxide (product name Omnirad TPO H, manufactured by IGM Resins Co.) was used.

The components were blended so as to have the blending compositions shown in table 1, and a liquid sealing material was obtained.

The unit of the compounding composition of the compound (a) and the compound (B) in table 1 is the mass part of the compound (a) or the compound (B) relative to 100 mass parts of the total of the compound (a) and the compound (B). In addition, the unit of the compounding composition of the heat stabilizer and the photo radical initiator in table 1 is mass% with respect to the total composition of the 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 obtained sealing material was measured for viscosity at 25℃and 20rpm using an E-type viscometer (LV DV-II+Pro, manufactured by BROOKFIELD Co.). The evaluation was performed according to the following criteria. The results are shown in table 1.

〇：5～50mPa·s

X: less than 5 mPas or greater than 50 mPas

(refractive index)

The refractive index of the cured film obtained by curing the obtained sealing material was evaluated in the following manner.

A Teflon (registered trademark) sheet having a thickness of 100 μm was used as a mold frame, the mold frame was placed on a transparent polyethylene terephthalate (PET) film, the sealing material obtained by the above method was injected thereinto, and the transparent PET film was further placed thereon, whereby the sealing material was sandwiched between 2 transparent PET films, and an illuminance of 1000mW/cm was measured using a UV-LED having a wavelength of 395nm ² The cumulative light quantity is 1500mJ/cm ² Is cured under the conditions of (2) to obtain a cured film.

The refractive index (nd) of the cured film was measured at room temperature (25 ℃) by using an Abbe refractometer (DR-M4, manufactured by Atago Co., ltd.) under d-ray (wavelength 587.6 nm). The evaluation was performed according to the following criteria. The results are shown in table 1.

And (2) the following steps: 1.60 or more

X: less than 1.60

(plasma resistance)

As plasma resistance, element damage in a plasma treatment process using a parallel plate type electron cyclotron resonance plasma CVD apparatus was evaluated by the following method.

The sealing material obtained by the above method was introduced into an inkjet cartridge DMC-11610 (manufactured by Fuji film Dimatix Co.). The ink jet cartridge was set in an ink jet device DMP-2831 (manufactured by Fuji photo Dimatix Co., ltd.) to adjust the ejection state, and then, the ink jet cartridge was coated on a glass substrate in a size of 15mm by 15mm so that the thickness after curing became 10. Mu.m.

The obtained coating film was placed in a box flowing nitrogen gas and adjusted to room temperature (25 ℃ C.), left standing for 5 minutes, and then UV-LED having a wavelength of 395nm was used at an illuminance of 1000mW/cm ² The cumulative light quantity is 1500mJ/cm ² Is irradiated under the condition of (2) to form a cured film.

An inorganic material film (SiN) having a film thickness of 1 μm was deposited on the surface of the cured film by using a parallel plate type electron cyclotron resonance plasma CVD apparatus at an output of 100W and a surface temperature of the cured film of 100 DEG C _x A film).

The obtained sample was put into a constant temperature and humidity tank at 85℃and 85%, and the appearance after 240 hours was observed. The evaluation was performed according to the following criteria. The results are shown in table 1.

And (2) the following steps: no whitening

X: whitening occurs

TABLE 1

As shown in table 1, the sealing materials and cured products thereof obtained in each example were excellent in the effect of suppressing damage to the element irradiated with plasma, and had a high refractive index and a low viscosity suitable for coating.

The present application claims priority based on japanese application publication No. 2020-191965, filed 11/18/2020, the entire disclosure of which is incorporated herein.

Symbol description

10 organic EL display element

21 st inorganic material film

22 st seal layer 1

23 No. 2 inorganic material film

24 nd sealing layer

25. Surface protection layer

50. Substrate material

100 organic EL display device.

Claims

1. A sealing material for organic EL display elements, which comprises a compound (A) having a (meth) acryloylthio group represented by the following general formula (1),

[ chemical 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 an organic EL display element according to claim 1, wherein the compound (a) is a compound having 2 or more (meth) acryloylthio groups.

3. The sealing material for an organic EL display element according to claim 1 or 2, further comprising a compound (B) having a (meth) acryloyl group, but the compound (B) does not include the compound (a).

4. The sealing material for an organic EL display element according to claim 3, wherein the compound (B) is a compound further having an aromatic group which may be substituted.

5. The sealing material for an organic EL display element according to any one of claims 1 to 4, wherein the viscosity at 25 ℃ and 20rpm is 5mpa·s to 50mpa·s as measured by an E-type viscometer.

6. The sealing material for an organic EL display element according to any one of claims 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 claims 1 to 6, which is used for forming a sealing layer in an organic EL display device having a structure in which an organic EL display element, a 1 st inorganic material film, a sealing layer, and a 2 nd inorganic material film are laminated in this order.

8. The sealing material for an organic EL display element according to any one of claims 1 to 7, wherein a sealing structure using a bank material and a filler is used as the filler.

9. A cured product obtained by curing the sealing material for an organic EL display element according to any one of claims 1 to 8.

10. An organic EL display device, comprising:

Organic EL display element and method of manufacturing the same

A sealing layer covering the organic EL display element,

the sealing layer contains the cured product according to claim 9.