JP7010824B2 - Encapsulant for organic EL display elements - Google Patents

Description

The present invention relates to a sealing agent for an organic EL display element capable of obtaining an organic EL display element having excellent inkjet coating property, low outgassing property, adhesion to an inorganic material film, and excellent reliability.

The organic electroluminescence (hereinafter, also referred to as “organic EL”) display element has a laminated structure in which an organic light emitting material layer is sandwiched between a pair of electrodes facing each other, and the organic light emitting material layer is connected to the organic light emitting material layer from one electrode. When electrons are injected and holes are injected from the other electrode, the electrons and holes are combined and emit light in the organic light emitting material layer. Since the organic EL display element emits light by itself in this way, it has better visibility than a liquid crystal display element or the like that requires a backlight, can be made thinner, and can be driven by a low DC voltage. It has the advantage of.

The organic light emitting material layer and electrodes constituting the organic EL display element have a problem that their characteristics are easily deteriorated by moisture, oxygen, and the like. Therefore, in order to obtain a practical organic EL display element, it is necessary to shield the organic light emitting material layer and the electrode from the atmosphere to extend the life. Patent Document 1 discloses a method of sealing an organic light emitting material layer of an organic EL display element and an electrode with a laminated film of a silicon nitride film and a resin film formed by a CVD method. Here, the resin film has a role of preventing pressure on the organic layer and electrodes due to the internal stress of the silicon nitride film.

In the method of sealing with the silicon nitride film disclosed in Patent Document 1, organic light emission occurs when the silicon nitride film is formed due to irregularities on the surface of the organic EL display element, adhesion of foreign matter, cracks due to internal stress, and the like. It may not be possible to completely cover the material layer or electrodes. If the coating with the silicon nitride film is incomplete, moisture will infiltrate into the organic light emitting material layer through the silicon nitride film.
As a method for preventing the infiltration of water into the organic light emitting material layer, Patent Document 2 discloses a method of alternately depositing an inorganic material film and a resin film, and Patent Documents 3 and 4 Discloses a method of forming a resin film on an inorganic material film.

As a method of forming a resin film, there is a method of applying a sealant on a substrate by using an inkjet method and then curing the sealant. By using such a coating method by an inkjet method, a resin film can be formed at high speed and uniformly. However, if the encapsulant has a low viscosity in order to be suitable for coating by the inkjet method, outgas may be generated, or the obtained organic EL display element may be inferior in reliability. There was a problem.

Japanese Unexamined Patent Publication No. 2000-223264 Special Table 2005-522891 Japanese Unexamined Patent Publication No. 2001-307873 Japanese Unexamined Patent Publication No. 2008-149710

INDUSTRIAL APPLICABILITY The present invention provides a sealing agent for an organic EL display element capable of obtaining an organic EL display element having excellent inkjet coatability, low outgassing property, adhesion to an inorganic material film, and excellent reliability. With the goal.

The present invention 1 is a sealing agent for an organic EL display element containing a polymerizable compound and a polymerization initiator, wherein the polymerizable compound contains a monofunctional oxetane compound and a polyfunctional oxetane compound, and the above-mentioned polymerization. The content of the monofunctional oxetane compound in 100 parts by weight of the sex compound is 20 parts by weight or more and 35 parts by weight or less, and the content of the polyfunctional oxetane compound is 25 parts by weight or more and 40 parts by weight or less. A sealant for an organic EL display element having a viscosity at 25 ° C. of 80 mPa · s or less and a surface tension of 15 mN / m or more and 35 mN / m or less at 25 ° C.
The present invention 2 is a sealing agent for an organic EL display element containing a polymerizable compound and a polymerization initiator. The polymerizable compound contains a monofunctional oxetane compound and a polyfunctional oxetane compound, and the polymerization thereof. The content of the monofunctional oxetane compound in 100 parts by weight of the sex compound is 20 parts by weight or more and 35 parts by weight or less, and the content of the polyfunctional oxetane compound is 25 parts by weight or more and 40 parts by weight or less. It is a sealant for an organic EL display element used for coating by an inkjet method.
The present invention will be described in detail below. The matters common to the sealant for the organic EL display element of the present invention 1 and the sealant for the organic EL display element of the present invention 2 are described as "the sealant for the organic EL display element of the present invention". do.

The present inventors have found that the reason why the organic EL display element obtained when the conventional sealant for an organic EL display element is used is inferior in reliability is the adhesion of the sealant to the inorganic material film. I thought it was inadequate. Therefore, the present inventors have blended a monofunctional oxetane compound and a polyfunctional oxetane compound as polymerizable compounds so as to have specific contents, and have the viscosity and surface tension within specific ranges, respectively. Considered adjusting. As a result, it is possible to obtain a sealing agent for an organic EL display element capable of obtaining an organic EL display element having excellent inkjet coating property, low outgassing property, adhesion to an inorganic material film, and excellent reliability. And came to complete the present invention.

The encapsulant for an organic EL display element of the present invention contains a polymerizable compound.
The polymerizable compound contains a monofunctional oxetane compound and a polyfunctional oxetane compound.
By using the monofunctional oxetane compound and the polyfunctional oxetane compound so as to have the contents described later, the encapsulant for an organic EL display element of the present invention has low outgassing property and adhesion to an inorganic material film. Will be excellent.

Examples of the monofunctional oxetane compound include 3-ethyl-3-((2-ethylhexyloxy) methyl) oxetane, phenoxymethyloxetane, 3-ethyl-3-hydroxymethyloxetane, and 3-ethyl-3- (phenoxymethyl). ) Oxetane, 3-ethyl-3-((3- (triethoxysilyl) propoxy) methyl) oxetane, 3-allyloxyoxetane, 3-ethyl-3-allyloxyoxetane, 3-ethyl-3-acryloyloxymethyloxetane , 3-Ethyl-3-methacryloxymethyloxetane, 2-methyl-2-allyl-4-propyloxetane, 3-ethyl-3- (4-acryloyloxybutyloxymethyl) oxetane, 3-ethyl-3- (3) -Acryloyloxy-2,2-dimethylpropyloxymethyl) oxetane, 3-methyl-3-methoxyoxetane, phenyloxetane, 3-ethyl-3-chloromethyloxetane, 3-ethyl-3-oxetanemethanol, 3-amino- Examples thereof include 3-dimethyloxetane. Of these, 3-ethyl-3-((2-ethylhexyloxy) methyl) oxetane is preferable from the viewpoint of further improving the adhesion to the inorganic material film.

The lower limit of the content of the monofunctional oxetane compound in 100 parts by weight of the polymerizable compound is 20 parts by weight, and the upper limit is 35 parts by weight. When the content of the monofunctional oxetane compound is in this range, the encapsulant for an organic EL display element of the present invention has excellent low outgassing properties and adhesion to an inorganic material film, and the obtained organic EL display element can be obtained. It will be highly reliable. The preferable lower limit of the content of the monofunctional oxetane compound is 22 parts by weight, the preferable upper limit is 33 parts by weight, the more preferable lower limit is 25 parts by weight, and the more preferable upper limit is 30 parts by weight.

Examples of the polyfunctional oxetane compound include 3-ethyl-3-(((3-ethyloxetane-3-yl) methoxy) methyl) oxetane, xylylenebis oxetane, phenol novolac-type oxetane, oxetanyl sylsesquioxane, and the like. 1,4-Bis ((3-ethyl-3-oxetanylmethoxy) methyl) benzene, bis ((3-methyl-3-oxetanylmethoxy) methyl) ether, bis ((3-ethyl-3-oxetanylmethoxy) methyl) In addition to ether, 1,4-bis ((3-methyl-3-oxetanylmethoxy) methyl) benzene, oligomers or copolymers thereof, calix allenes, calix resorcin allenes, cardo-type bisphenols, etc. , Poly (p-hydroxystyrene), or an etherified product with a resin having a hydroxyl group such as silsesquioxane. Of these, a bifunctional oxetane compound is preferable, and 3-ethyl-3-(((3-ethyloxetane-3-yl) methoxy) methyl) oxetane is more preferable from the viewpoint of inkjet coatability and the like.

The lower limit of the content of the polyfunctional oxetane compound in 100 parts by weight of the polymerizable compound is 25 parts by weight, and the upper limit is 40 parts by weight. When the content of the polyfunctional oxetane compound is in this range, the encapsulant for an organic EL display element of the present invention has excellent low outgassing properties and adhesion to an inorganic material film, and the obtained organic EL display element can be obtained. It will be highly reliable. The preferable lower limit of the content of the polyfunctional oxetane compound is 28 parts by weight, the preferable upper limit is 38 parts by weight, and the more preferable upper limit is 35 parts by weight.

The content ratio of the monofunctional oxetane compound to the polyfunctional oxetane compound is preferably a monofunctional oxetane compound: polyfunctional oxetane compound = 5: 3 to 5: 9 in terms of weight ratio. When the content ratio of the monofunctional oxetane compound and the polyfunctional oxetane compound is in this range, the obtained sealing agent for an organic EL display element becomes excellent in low outgassing property and adhesion to an inorganic material film. The organic EL display element to be used becomes more reliable.

The polymerizable compound preferably contains a cycloalkene oxide type alicyclic epoxy compound.
By containing the cycloalkene oxide type alicyclic epoxy compound, the obtained sealing agent for an organic EL display element becomes excellent in low outgassing property and barrier property (moisture permeation prevention property) of the cured product.
Further, by containing the cycloalkene oxide type alicyclic epoxy compound, coloring of the encapsulant due to heat or light is less likely to occur, and loss of EL light emission and change in color tone due to absorption of the encapsulant can be reduced.
In the present specification, the above-mentioned "cycloalkene oxide type alicyclic epoxy compound" has a structure in which a carbon-carbon double bond of cycloalkene is epoxidized, for example, as represented by the following formula (1). Hereinafter, it means a compound having a "cycloalkene oxide skeleton").

In the formula (1), R ¹ to R ⁹ are hydrocarbon groups which may contain a hydrogen atom, a halogen atom, an oxygen atom or a halogen atom, and may be the same or different from each other. May be good. * Represents the bond position.

The preferable lower limit of the epoxy group equivalent of the cycloalkene oxide type alicyclic epoxy compound is 50 g / mol, and the preferable upper limit is 400 g / mol. When the epoxy group equivalent of the cycloalkene oxide type alicyclic epoxy compound is in this range, the obtained cured product of the sealant for an organic EL display element suppresses the generation of cracks due to heating or deformation, and is a barrier. It will be superior to the sex. The more preferable lower limit of the epoxy group equivalent of the cycloalkene oxide type alicyclic epoxy compound is 70 g / mol, and the more preferable upper limit is 300 g / mol.
The epoxy group equivalent of the cycloalkene oxide type alicyclic epoxy compound is the weight (g) of the cycloalkene oxide type alicyclic epoxy compound per 1 mol of the epoxy group contained in the cycloalkene oxide type alicyclic epoxy compound. Means.

The preferred lower limit of the molecular weight of the cycloalkene oxide type alicyclic epoxy compound is 150, and the preferred upper limit is 7000. When the molecular weight of the cycloalkene oxide type alicyclic epoxy compound is in this range, the sealing agent for an organic EL display element obtained while suppressing the generation of outgas is more excellent in the barrier property of the cured product. The more preferable lower limit of the molecular weight of the cycloalkene oxide type alicyclic epoxy compound is 200, the more preferable upper limit is 5000, the further preferable lower limit is 250, and the further preferable upper limit is 1000.
The molecular weight of the cycloalkene oxide type alicyclic epoxy compound is the molecular weight obtained from the structural formula for the compound whose molecular structure is specified, but the compound having a wide distribution of the degree of polymerization and the modification site are unspecified. Compounds may be expressed using the weight average molecular weight. In the present specification, the above-mentioned "weight average molecular weight" is a value obtained by measuring by gel permeation chromatography (GPC) and converting into polystyrene. Examples of the column used when measuring the weight average molecular weight in terms of polystyrene by GPC include Shodex LF-804 (manufactured by Showa Denko KK) and the like.

The cycloalkene oxide type alicyclic epoxy compound may be a compound having only one cycloalkene oxide skeleton in the structure or in a repeating unit, and is a compound having two or more cycloalkene oxide skeletons. However, a compound having two or more cycloalkene oxide skeletons is preferably used. When the cycloalkene oxide type alicyclic epoxy compound is a compound having two or more cycloalkene oxide skeletons, the encapsulant for an organic EL display element of the present invention is more excellent in light resistance, barrier property and the like. Will be.

Specific examples of the cycloalkene oxide type alicyclic epoxy compound include, for example, 3', 4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4,3', 4'-diepoxy. Examples thereof include bicyclohexane and bis (3,4-epoxycyclohexylmethyl) ether. Among them, 3', 4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4,3', 4'-diepoxybicyclohexane are selected from the viewpoint of low outgassing property and barrier property of cured product. preferable.

The preferable lower limit of the content of the cycloalkene oxide type alicyclic epoxy compound in 100 parts by weight of the polymerizable compound is 15 parts by weight, and the preferable upper limit is 30 parts by weight. When the content of the cycloalkene oxide type alicyclic epoxy compound is in this range, the obtained sealing agent for an organic EL display element is excellent in low outgassing property and barrier property of a cured product. The more preferable lower limit of the content of the cycloalkene oxide type alicyclic epoxy compound is 17 parts by weight, and the more preferable upper limit is 25 parts by weight.

The polymerizable compound preferably contains an alkyl polyol type epoxy compound.
By containing the above-mentioned alkyl polyol type epoxy compound, the obtained sealing agent for an organic EL display element becomes more excellent in adhesion.

Examples of the alkyl polyol type epoxy compound include neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, and tripropylene. Examples thereof include glycol diglycidyl ether, polypropylene glycol diglycidyl ether, glycerin diglycidyl ether, and trimethylol propantriglycidyl ether. Of these, neopentyl glycol diglycidyl ether is preferable from the viewpoint of adhesion.

The preferable lower limit of the content of the alkyl polyol type epoxy compound in 100 parts by weight of the polymerizable compound is 5 parts by weight, and the preferable upper limit is 30 parts by weight. When the content of the alkyl polyol type epoxy compound is in this range, the obtained sealing agent for an organic EL display element becomes more excellent in adhesion. The more preferable lower limit of the content of the alkyl polyol type epoxy compound is 10 parts by weight, and the more preferable upper limit is 25 parts by weight.

The polymerizable compound is a monofunctional oxetane compound, a polyfunctional oxetane compound, a cycloalkene oxide type alicyclic epoxy compound, and other than the alkyl polyol type epoxy compound, as long as the object of the present invention is not impaired. May contain a polymerizable compound of.
Examples of the other polymerizable compound include other epoxy compounds other than the cycloalkene oxide type alicyclic epoxy compound and the alkyl polyol type epoxy compound, vinyl ether compounds and the like.

Examples of the other epoxy compounds include bisphenol A type epoxy resin, bisphenol E type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol O type epoxy resin, and 2,2'-diallyl bisphenol A type epoxy. Resin, hydrogenated bisphenol type epoxy resin, propylene oxide added bisphenol A type epoxy resin, resorcinol type epoxy resin, biphenyl type epoxy resin, sulfide type epoxy resin, diphenyl ether type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, Phenol novolak type epoxy resin, orthocresol novolak type epoxy resin, dicyclopentadiene novolak type epoxy resin, biphenyl novolak type epoxy resin, naphthalenephenol novolak type epoxy resin, glycidylamine type epoxy resin, rubber-modified epoxy resin, glycidyl ester compound, etc. Can be mentioned.

Examples of the vinyl ether compound include benzyl vinyl ether, cyclohexanedimethanol monovinyl ether, dicyclopentadienvinyl ether, 1,4-butanediol divinyl ether, cyclohexanedimethanol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, and dipropylene glycol. Examples thereof include divinyl ether and tripropylene glycol divinyl ether.

The encapsulant for an organic EL display element of the present invention contains a polymerization initiator.
As the polymerization initiator, a photocationic polymerization initiator or a thermal cationic polymerization initiator is preferably used.

The photocationic polymerization initiator is not particularly limited as long as it generates protonic acid or Lewis acid by light irradiation, and may be an ionic photoacid generation type or a nonionic photoacid generation type. May be.

As the anionic moiety of the above-mentioned ionic photoacid generation type photocationic polymerization initiator, for example, the anionic moiety is BF _4- ^, PF _6- ^, SbF _6- , or (BX ₄ ^{)- (} where X is at least (Representing a phenyl group substituted with two or more fluorine or trifluoromethyl groups) and the like.
Examples of the ionic photoacid generation type photocationic polymerization initiator include aromatic sulfonium salts, aromatic iodonium salts, aromatic diazonium salts, and aromatic ammonium salts, which have the anion moiety. Examples thereof include pentadiene-1-yl) ((1-methylethyl) benzene) -Fe salt and the like.

Examples of the aromatic sulfonium salt include bis (4- (diphenylsulfonio) phenyl) sulfide bishexafluorophosphate, bis (4- (diphenylsulfonio) phenyl) sulfide bishexafluoroantimonate, and bis (4- (4). Diphenylsulfonio) phenyl) sulfide bistetrafluoroborate, bis (4- (diphenylsulfonio) phenyl) sulfide tetrakis (pentafluorophenyl) borate, diphenyl-4- (phenylthio) phenylsulfonium hexafluorophosphate, diphenyl-4- ( Phenylthio) phenylsulfonium hexafluoroantimonate, diphenyl-4- (phenylthio) phenylsulfonium tetrafluoroborate, diphenyl-4- (phenylthio) phenylsulfonium tetrakis (pentafluorophenyl) borate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexa Fluoroantimonate, triphenylsulfonium tetrafluoroborate, triphenylsulfonium tetrakis (pentafluorophenyl) borate, triarylsulfonium tetrakis (pentafluorophenyl) borate, bis (4- (di (4- (2-hydroxyethoxy)) phenyl) Sulfonio) phenyl) sulfide bishexafluorophosphate, bis (4- (di (4- (2-hydroxyethoxy)) phenylsulfonio) phenyl) sulfide bishexafluoroantimonate, bis (4- (di (4- (4- (2-hydroxyethoxy))) 2-Hydroxyethoxy)) phenylsulfonio) phenyl) sulfide bistetrafluoroborate, bis (4- (di (4- (2-hydroxyethoxy)) phenylsulfonio) phenyl) sulfide tetrakis (pentafluorophenyl) borate, tris (4- (4-Acetylphenyl) thiophenyl) sulfonium tetrakis (pentafluorophenyl) borate and the like can be mentioned.

Examples of the aromatic iodonium salt include diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, diphenyliodonium tetrafluoroborate, diphenyliodonium tetrakis (pentafluorophenyl) borate, bis (dodecylphenyl) iodonium hexafluorophosphate, and bis. (Dodecylphenyl) Iodineium hexafluoroantimonate, bis (dodecylphenyl) iodonium tetrafluoroborate, bis (dodecylphenyl) iodonium tetrakis (pentafluorophenyl) borate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium hexa Fluorophosphate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium hexafluoroantimonate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium tetrafluoroborate, 4-methylphenyl-4-( 1-Methylethyl) Phenyliodonium tetrakis (pentafluorophenyl) borate and the like can be mentioned.

Examples of the aromatic diazonium salt include phenyldiazonium hexafluorophosphate, phenyldiazonium hexafluoroantimonate, phenyldiazonium tetrafluoroborate, and phenyldiazonium tetrakis (pentafluorophenyl) borate.

Examples of the aromatic ammonium salt include 1-benzyl-2-cyanopyridinium hexafluorophosphate, 1-benzyl-2-cyanopyridinium hexafluoroantimonate, 1-benzyl-2-cyanopyridinium tetrafluoroborate and 1-benzyl. -2-Cyanopyridinium tetrakis (pentafluorophenyl) boronate, 1- (naphthylmethyl) -2-cyanopyridinium hexafluorophosphate, 1- (naphthylmethyl) -2-cyanopyridinium hexafluoroantimonate, 1- (naphthylmethyl) Examples thereof include -2-cyanopyridinium tetrafluoroborate and 1- (naphthylmethyl) -2-cyanopyridinium tetrakis (pentafluorophenyl) volate.

Examples of the (2,4-cyclopentadiene-1-yl) ((1-methylethyl) benzene) -Fe salt include (2,4-cyclopentadiene-1-yl) ((1-methylethyl) benzene. ) -Fe (II) hexafluorophosphate, (2,4-cyclopentadiene-1-yl) ((1-methylethyl) benzene) -Fe (II) hexafluoroantimonate, (2,4-cyclopentadiene-1) -Il) ((1-methylethyl) benzene) -Fe (II) tetrafluoroborate, (2,4-cyclopentadiene-1-yl) ((1-methylethyl) benzene) -Fe (II) tetrakis (penta) Fluorophenyl) Borate and the like can be mentioned.

Examples of the nonionic photoacid generation type photocationic polymerization initiator include nitrobenzyl ester, sulfonic acid derivative, phosphoric acid ester, phenol sulfonic acid ester, diazonaphthoquinone, N-hydroxyimide sulfonate and the like.

Commercially available photocationic polymerization initiators include, for example, a photocationic polymerization initiator manufactured by Midori Chemical Co., Ltd., a photocationic polymerization initiator manufactured by Union Carbide, and a photocationic polymerization initiator manufactured by ADEKA. Examples thereof include a photocationic polymerization initiator manufactured by 3M, a photocationic polymerization initiator manufactured by BASF, and a photocationic polymerization initiator manufactured by Rhodia.
Examples of the photocationic polymerization initiator manufactured by Midori Kagaku Co., Ltd. include DTS-200 and the like.
Examples of the photocationic polymerization initiator manufactured by Union Carbide include UVI6990 and UVI6974.
Examples of the photocationic polymerization initiator manufactured by ADEKA include SP-150 and SP-170.
Examples of the photocationic polymerization initiator manufactured by 3M include FC-508 and FC-512.
Examples of the photocationic polymerization initiator manufactured by BASF include IRGACURE261 and IRGACURE290.
Examples of the photocationic polymerization initiator manufactured by Rhodia include PI2074 and the like.

In the above thermal cationic polymerization initiator, the anionic moiety is replaced with BF _4- , PF _6- ^, SbF _6- ^, or (BX ₄ ^- ) ^- (where X is substituted with at least two or more fluorine or trifluoromethyl groups. Examples thereof include a sulfonium salt, a phosphonium salt, an ammonium salt, etc., which are composed of (representing a phenyl group). Of these, sulfonium salts and ammonium salts are preferable.

Examples of the sulfonium salt include triphenylsulfonium tetrafluoroborate and triphenylsulfonium hexafluoroantimonate.

Examples of the phosphonium salt include ethyltriphenylphosphonium hexafluoroantimonate and tetrabutylphosphonium hexafluoroantimonate.

Examples of the ammonium salt include dimethylphenyl (4-methoxybenzyl) ammonium hexafluorophosphate, dimethylphenyl (4-methoxybenzyl) ammonium hexafluoroantimonate, and dimethylphenyl (4-methoxybenzyl) ammonium tetrakis (pentafluorophenyl). Borate, dimethylphenyl (4-methylbenzyl) ammonium hexafluorophosphate, dimethylphenyl (4-methylbenzyl) ammonium hexafluoroantimonate, dimethylphenyl (4-methylbenzyl) ammonium hexafluorotetrakis (pentafluorophenyl) borate, methylphenyl Dibenzylammonium hexafluorophosphate, methylphenyldibenzylammonium hexafluoroantimonate, methylphenyldibenzylammonium tetrakis (pentafluorophenyl) borate, phenyltribenzylammonium tetrakis (pentafluorophenyl) borate, dimethylphenyl (3,4-dimethyl) Benzyl) ammonium tetrakis (pentafluorophenyl) borate, N, N-dimethyl-N-benzylanilinium hexafluoroantimonate, N, N-diethyl-N-benzylanilinium tetrafluoroborate, N, N-dimethyl-N- Benzylpyridinium hexafluoroantimonate, N, N-diethyl-N-benzylpyridinium trifluoromethanesulfonic acid and the like can be mentioned.

Examples of commercially available thermal cationic polymerization initiators include thermal cationic polymerization initiators manufactured by Sanshin Chemical Industry Co., Ltd., thermal cationic polymerization initiators manufactured by King Industries, and the like.
Examples of the thermal cationic polymerization initiator manufactured by Sanshin Chemical Industry Co., Ltd. include Sun Aid SI-60, Sun Aid SI-80, Sun Aid SI-B3, Sun Aid SI-B3A, and Sun Aid SI-B4.
Examples of the thermal cationic polymerization initiator manufactured by King Industries include CXC1612, CXC1821 and the like.

The content of the polymerization initiator has a preferable lower limit of 0.01 parts by weight and a preferable upper limit of 10 parts by weight with respect to 100 parts by weight of the polymerizable compound. When the content of the polymerization initiator is 0.01 parts by weight or more, the obtained sealing agent for an organic EL display element becomes more excellent in curability. When the content of the polymerization initiator is 10 parts by weight or less, the curing reaction of the obtained sealant for an organic EL display element does not become too fast, the workability is improved, and the cured product becomes more uniform. Can be. The more preferable lower limit of the content of the polymerization initiator is 0.05 parts by weight, and the more preferable upper limit is 5 parts by weight.

The encapsulant for an organic EL display element of the present invention may contain a sensitizer. The sensitizer has a role of further improving the polymerization initiation efficiency of the polymerization initiator and further promoting the curing reaction of the encapsulant for an organic EL display element of the present invention.

Examples of the sensitizer include thioxanthone compounds, 2,2-dimethoxy-1,2-diphenylethane-1-one, benzophenone, 2,4-dichlorobenzophenone, methyl o-benzoylbenzoate, 4,4'. -Bis (dimethylamino) benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide and the like can be mentioned.
Examples of the thioxanthone compound include 2,4-diethylthioxanthone and the like.

Regarding the content of the sensitizer, the preferable lower limit is 0.01 part by weight and the preferable upper limit is 3 parts by weight with respect to 100 parts by weight of the polymerizable compound. When the content of the sensitizer is 0.01 parts by weight or more, the sensitizing effect is more exhibited. When the content of the sensitizer is 3 parts by weight or less, light can be transmitted to a deep part without excessive absorption. The more preferable lower limit of the content of the sensitizer is 0.1 parts by weight, and the more preferable upper limit is 1 part by weight.

The encapsulant for an organic EL display element of the present invention may contain a silane coupling agent. The silane coupling agent has a role of improving the adhesiveness between the sealing agent for an organic EL display element of the present invention and a substrate or the like.

Examples of the silane coupling agent include 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-isocyanatepropyltrimethoxysilane and the like. These silane coupling agents may be used alone or in combination of two or more.

Regarding the content of the silane coupling agent, the preferable lower limit is 0.1 part by weight and the preferable upper limit is 10 parts by weight with respect to 100 parts by weight of the polymerizable compound. When the content of the silane coupling agent is in this range, the effect of improving the adhesiveness while suppressing the bleed-out of the excess silane coupling agent becomes more excellent. The more preferable lower limit of the content of the silane coupling agent is 0.5 parts by weight, and the more preferable upper limit is 5 parts by weight.

The encapsulant for an organic EL display element of the present invention may further contain a surface modifier as long as the object of the present invention is not impaired. By containing the above-mentioned surface modifier, the flatness of the coating film can be imparted to the sealing agent for the organic EL display element of the present invention.
Examples of the surface modifier include a surfactant, a leveling agent and the like.

Examples of the surface modifier include silicone-based and fluorine-based agents.
Examples of commercially available surface modifiers include BYK-340, BYK-345 (all manufactured by Big Chemie Japan), Surflon S-611 (manufactured by AGC Seimi Chemical Co., Ltd.) and the like.

The encapsulant for an organic EL display element of the present invention may contain a solvent for the purpose of adjusting the viscosity, but there are problems such as deterioration of the organic light emitting material layer and generation of outgas due to the remaining solvent. It is preferable that the solvent is not contained or the solvent content is 0.05% by weight or less.

Further, the sealing agent for an organic EL display element of the present invention contains various known additives such as a reinforcing agent, a softening agent, a plasticizer, a viscosity modifier, an ultraviolet absorber, and an antioxidant, if necessary. May be.

As a method for producing the sealant for an organic EL display element of the present invention, for example, a mixer such as a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, or a three-roll is used to obtain a polymerizable compound. , A method of mixing the polymerization initiator and an additive such as a silane coupling agent to be added as needed can be mentioned.

The sealant for an organic EL display element of the present invention 1 has an upper limit of viscosity of 80 mPa · s at 25 ° C. When the viscosity is 80 mPa · s or less, the sealant for an organic EL display element of the present invention 1 has excellent inkjet coatability. The preferable upper limit of the viscosity of the sealing agent for an organic EL display element of the present invention 1 is 60 mPa · s, and the more preferable upper limit is 20 mPa · s.
Further, the preferable lower limit of the viscosity of the sealing agent for the organic EL display element of the present invention 1 is 5 mPa · s.
In the present specification, the viscosity means a value measured under the conditions of 25 ° C. and 100 rpm using an E-type viscometer.

The sealant for an organic EL display element of the present invention 2 has a preferable upper limit of viscosity at 25 ° C. of 80 mPa · s. When the viscosity is 80 mPa · s or less, the sealant for an organic EL display element of the present invention 2 is superior in inkjet coating property. A more preferable upper limit of the viscosity of the sealing agent for an organic EL display element of the present invention 2 is 60 mPa · s, and a further preferable upper limit is 20 mPa · s.
Further, the preferable lower limit of the viscosity of the sealing agent for the organic EL display element of the present invention 2 is 5 mPa · s.

The sealant for an organic EL display element of the present invention 1 has a lower limit of surface tension of 15 mN / m and an upper limit of 35 mN / m at 25 ° C. When the surface tension is within this range, the sealant for an organic EL display element of the present invention 1 has excellent inkjet coatability. The preferable lower limit of the surface tension of the sealant for an organic EL display element of the present invention 1 is 20 mN / m, the preferable upper limit is 30 mN / m, the more preferable lower limit is 22 mN / m, and the more preferable upper limit is 28 mN / m.
The surface tension can be measured by a dynamic wettability tester at 25 ° C.

In the sealant for an organic EL display element of the present invention 2, the preferable lower limit of the surface tension at 25 ° C. is 15 mN / m, and the preferable upper limit is 35 mN / m. When the surface tension is within this range, the sealant for an organic EL display element of the present invention 2 is superior in inkjet coatability. The more preferable lower limit of the surface tension of the sealant for an organic EL display element of the present invention 2 is 20 mN / m, the more preferable upper limit is 30 mN / m, the further preferable lower limit is 22 mN / m, and the further preferable upper limit is 28 mN / m.

The preferable lower limit of the total light transmittance of light at a wavelength of 380 to 800 nm of the cured product of the sealant for an organic EL display element of the present invention is 80%. When the total light transmittance is 80% or more, the obtained organic EL display element is superior in optical characteristics. A more preferable lower limit of the total light transmittance is 85%.
The total light transmittance can be measured using, for example, a spectroscope such as AUTOMATIC HAZE METER MODEL TC-III DPK (manufactured by Tokyo Denshoku Co., Ltd.). Further, the cured product used for measuring the light transmittance and the moisture permeability and water content described later can be obtained by irradiating 3000 mJ / cm ² of ultraviolet rays having a wavelength of 365 nm using a light source such as an LED lamp. can.

The encapsulant for an organic EL display element of the present invention preferably has a transmittance of 85% or more at an optical path length of 20 μm at 400 nm after irradiating the cured product with ultraviolet rays for 100 hours. When the transmittance after irradiation with the ultraviolet rays for 100 hours is 85% or more, the transparency is high, the loss of light emission is small, and the color reproducibility is excellent. A more preferable lower limit of the transmittance after irradiation with the ultraviolet rays for 100 hours is 90%, and a further preferable lower limit is 95%.
As the light source for irradiating the ultraviolet rays, a conventionally known light source such as a xenon lamp or a carbon arc lamp can be used.

The encapsulant for an organic EL display element of the present invention has a moisture permeability of 100 g / g at a thickness of 100 μm measured by exposing a cured product to an environment of 85 ° C. and 85% RH for 24 hours in accordance with JIS Z 0208. It is preferably m ² or less. When the moisture permeability is 100 g / m ² or less, the effect of preventing the deterioration of the organic light emitting material layer due to the moisture in the cured product becomes excellent, and the obtained organic EL display element becomes more excellent in reliability.

The encapsulant for an organic EL display element of the present invention preferably has a water content of less than 0.5% when the cured product is exposed to an environment of 85 ° C. and 85% RH for 24 hours. When the water content of the cured product is less than 0.5%, the effect of preventing deterioration of the organic light emitting material layer due to moisture in the cured product is more excellent, and the obtained organic EL display element is more reliable. It becomes. A more preferable upper limit of the water content of the cured product is 0.3%.
Examples of the method for measuring the water content include a method of obtaining by the Karl Fischer method according to JIS K 7251 and a method of obtaining the weight increment after water absorption according to JIS K 7209-2.

As a method for manufacturing an organic EL display element using the sealant for an organic EL display element of the present invention, for example, a step of applying the sealant for an organic EL display element of the present invention to a substrate by an inkjet method. Examples thereof include a method having a step of curing the applied sealing agent for an organic EL display element by light irradiation and / or heating.

In the step of applying the sealing agent for an organic EL display element of the present invention to a base material, the sealing agent for an organic EL display element of the present invention may be applied to the entire surface of the base material, or may be applied to a part of the base material. It may be applied. The shape of the sealing portion of the sealing agent for the organic EL display element of the present invention formed by coating is not particularly limited as long as it can protect the laminated body having the organic light emitting material layer from the outside air, and the laminated body is not particularly limited. The shape may be a shape that completely covers the body, a closed pattern may be formed in the peripheral portion of the laminated body, or a pattern having a partially opened portion in the peripheral portion of the laminated body may be formed. It may be formed.

When the sealing agent for an organic EL display element of the present invention is cured by light irradiation, the sealing agent for an organic EL display element of the present invention has a wavelength of 300 nm or more and 400 nm or less and 300 mJ / cm ² or more and 3000 mJ / cm ² or less. It can be suitably cured by irradiating it with a total amount of light.

Examples of the light source used for the above light irradiation include a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, an excima laser, a chemical lamp, a black light lamp, a microwave pumped mercury lamp, a metal halide lamp, a sodium lamp, a halogen lamp, and a xenon. Examples include lamps, LED lamps, fluorescent lamps, sunlight, and electron beam irradiators. These light sources may be used alone or in combination of two or more.
These light sources are appropriately selected according to the absorption wavelength of the photocationic polymerization initiator.

Examples of the means for irradiating the sealant for an organic EL display element of the present invention with light include simultaneous irradiation of various light sources, sequential irradiation with a time lag, combined irradiation of simultaneous irradiation and sequential irradiation, and the like. Any irradiation means may be used.

The cured product obtained by the step of curing the sealant for an organic EL display element by light irradiation and / or heating may be further coated with an inorganic material film.
As the inorganic material constituting the inorganic material film, conventionally known materials can be used, and examples thereof include silicon nitride (SiN _x ) and silicon oxide (SiO _x ). The inorganic material film may be composed of one layer or may be a laminated layer of a plurality of types. Further, the inorganic material film and the resin film made of the sealant for the organic EL display element of the present invention may be alternately repeated to coat the laminate.

The method for manufacturing the organic EL display element comprises a step of bonding a base material coated with the sealing agent for an organic EL display element of the present invention (hereinafter, also referred to as "one base material") and the other base material. You may have.
The base material (hereinafter, also referred to as “one base material”) to which the sealant for the organic EL display element of the present invention is applied may be a base material on which a laminate having an organic light emitting material layer is formed. , The base material on which the laminated body is not formed may be used.
When the one base material is a base material on which the laminated body is not formed, the present invention is applied to the one base material so that the laminated body can be protected from the outside air when the other base material is bonded. The sealant for the organic EL display element of the above may be applied. That is, either the entire surface is applied to the position of the laminated body when the other base material is bonded, or the position of the laminated body is completely formed when the other base material is bonded. A sealant portion having a closed pattern may be formed in a shape that fits within the shape of the sealant.

The step of curing the sealant for an organic EL display element by light irradiation and / or heating may be performed before the step of bonding the one base material and the other base material, or one of the above. It may be performed after the step of bonding the base material and the other base material.
When the step of curing the sealant for an organic EL display element by light irradiation and / or heating is performed before the step of bonding the one base material and the other base material, the organic EL display of the present invention is performed. It is preferable that the sealant for an element has a pot life of 1 minute or more from the time when it is irradiated with light and / or heated until the curing reaction proceeds and adhesion cannot be achieved. When the pot life is 1 minute or more, higher adhesive strength can be obtained without excessive curing before the one base material and the other base material are bonded together.

In the step of bonding the one base material and the other base material, the method of bonding the one base material and the other base material is not particularly limited, but it is preferable to bond them in a reduced pressure atmosphere.
The preferable lower limit of the degree of vacuum under the reduced pressure atmosphere is 0.01 kPa, and the preferable upper limit is 10 kPa. When the degree of vacuum under the reduced pressure atmosphere is within this range, one of the base materials and the other base can be used without spending a long time to achieve a vacuum state due to the airtightness of the vacuum device and the capacity of the vacuum pump. It is possible to more efficiently remove air bubbles in the encapsulant for an organic EL display element of the present invention when the material is bonded.

According to the present invention, there is provided a sealing agent for an organic EL display element capable of obtaining an organic EL display element having excellent inkjet coating property, low outgassing property, adhesion to an inorganic material film, and excellent reliability. can do.

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

(Examples 1 to 15, Comparative Examples 1 to 4)
According to the compounding ratios shown in Tables 1 to 3, each material was uniformly stirred and mixed at a stirring speed of 3000 rpm using a homodisper type stirring / mixing machine (“Homodisper L type” manufactured by Primix Corporation). Sealants for organic EL display elements of Examples 1 to 15 and Comparative Examples 1 to 4 were produced.
The sealants for organic EL display elements obtained in Examples and Comparative Examples were measured using an E-type viscometer (“VISCOMETER TV-22” manufactured by Toki Sangyo Co., Ltd.) at 25 ° C. and 100 rpm. Tables 1 to 3 show the viscosity and the surface tension measured by a dynamic wettability tester (“WET-6100 type” manufactured by Resca) at 25 ° C.

<Evaluation>
The following evaluations were performed on the sealants for each organic EL display element obtained in Examples and Comparative Examples. The results are shown in Tables 1 to 3.

(1) Inkjet coating property (1-1) Inkjet ejection property A sealing agent for each organic EL display element obtained in Examples and Comparative Examples is used with an inkjet ejection device (“NanoPrinter500” manufactured by Microjet Co., Ltd.). , 1000 drops were applied at a rate of 5 m / sec on a non-alkali glass (“AN100” manufactured by Asahi Glass Co., Ltd.) that had been alkaline-cleaned with a droplet volume of 30 picolitres at a pitch of 500 μm.
"◎" when the number of droplets that could not be applied was 0, "○" when the number of droplets that could not be applied was 1 or more and less than 5, and the droplets that could not be applied. The inkjet ejection property was evaluated as "Δ" when the number of droplets was 5 or more and less than 20, and "x" when the number of droplets that could not be applied was 20 or more.

(1-2) Wetting and Spreadability 30 picolitres of the sealant for each organic EL display element obtained in Examples and Comparative Examples are used with an inkjet ejection device (“NanoPrinter500” manufactured by Microjet Co., Ltd.). In terms of the amount of drops, 1000 drops were applied on non-alkali glass (manufactured by Asahi Glass Co., Ltd., "AN100") washed with alkali at a rate of 5 m / sec at a pitch of 500 μm. The diameter of the droplet on the non-alkali glass 10 minutes after application was measured, and when the diameter of the droplet was 150 μm or more, “◎”, and when the diameter of the droplet was 50 μm or more and less than 150 μm, “◎”. ◯ ”, and the case where the diameter of the droplet was less than 50 μm was evaluated as“ × ”to evaluate the wet spreadability.

(2) Low outgas properties The outgas generated during heating of the cured product of the sealant for each organic EL display element obtained in Examples and Comparative Examples was measured by a gas chromatograph by the headspace method shown below.
First, 100 mg of the sealant for each organic EL display element was applied to a thickness of 300 μm with an applicator, and then the sealant was cured by irradiating with an LED lamp an ultraviolet ray having a wavelength of 365 nm at 3000 mJ / cm ² . Next, the obtained cured sealant was placed in a headspace vial, the vial was sealed, heated at 100 ° C. for 30 minutes, and the generated gas was measured by the headspace method.
The low outgas property was evaluated as "⊚" when the generated gas was less than 300 ppm, "◯" when it was 300 ppm or more and less than 500 ppm, and "x" when it was 500 ppm or more.

(3) Adhesion to Inorganic Material Film A sealant for each organic EL display element obtained in Examples and Comparative Examples was used on a glass on which a silicon nitride film having a film thickness of 300 nm was formed in advance, using a spin coater. It was applied to a thickness of 10 μm. Next, the LED lamp was irradiated with ultraviolet rays having a wavelength of 365 nm ² at 3000 mJ / cm, and further heated at 100 ° C. for 30 minutes to cure the sealing agent for an organic EL display element to obtain a resin film.
A cross-cut test with a cutting interval of 1 mm was performed on the formed resin film according to JIS K 5600-5-6. When the cross-cut test was performed, the peeling was 5% or less as "◎", the peeling was more than 5% and 35% or less as "○", and the peeling was more than 35% and 65% or less. The case where it was "Δ" and the case where the peeling exceeded 65% was "x", and the adhesion to the inorganic material film was evaluated.

(4) Transparency The sealants for organic EL display elements obtained in Examples and Comparative Examples were applied onto glass using a spin coater. Next, the sealant was cured by irradiating with an LED lamp an ultraviolet ray having a wavelength of 365 nm ² at 3000 mJ / cm to prepare a test piece having a thickness of 10 μm. For the obtained test piece, the haze value (cloudiness value) of light at a wavelength of 380 to 800 nm was measured using a spectroscope (AUTOMATIC HAZE METER MODEL TC-III DPK, manufactured by Tokyo Denshoku Co., Ltd.). Transparency is defined as "◎" when the haze value is 0.3% or less, "○" when it exceeds 0.3% and 1% or less, and "×" when it exceeds 1%. evaluated.

(5) Reliability of organic EL display element (5-1) Fabrication of a substrate on which a laminate having an organic light emitting material layer is arranged An ITO electrode is placed on a glass substrate (length 25 mm, width 25 mm, thickness 0.7 mm). A film formed with a thickness of 1000 Å was used as a substrate. The substrate is ultrasonically washed with acetone, an alkaline aqueous solution, ion-exchanged water, and isopropyl alcohol for 15 minutes each, then washed with boiled isopropyl alcohol for 10 minutes, and further, a UV-ozone cleaner (manufactured by Nippon Laser Electronics Co., Ltd.). Immediate treatment was performed with "NL-UV253").
Next, this substrate was fixed to the substrate folder of the vacuum vapor deposition apparatus, and 200 mg of N, N'-di (1-naphthyl) -N, N'-diphenylbenzidine (α-NPD) was added to the unglazed crucible for another unglazed. 200 mg of tris (8-quinolinolat) aluminum (Alq ₃ ) was placed in the crucible, and the pressure inside the vacuum chamber was reduced to 1 × 10 ^-4 Pa. Then, the crucible containing α-NPD was heated, α-NPD was deposited on the substrate at a vapor deposition rate of 15 Å / s, and a hole transport layer having a film thickness of 600 Å was formed. Next, the crucible containing Alq ₃ was heated to form an organic light emitting material layer having a film thickness of 600 Å at a vapor deposition rate of 15 Å / s. After that, the substrate on which the hole transport layer and the organic light emitting material layer were formed was transferred to another vacuum vapor deposition apparatus, and lithium fluoride 200 mg was transferred to a tungsten resistance heating boat in this vacuum vapor deposition apparatus, and aluminum wire was transferred to another tungsten boat. 1.0 g was added. Then, the inside of the vapor deposition device of the vacuum vapor deposition apparatus is depressurized to 2 × 10 ^-4 Pa to form 5 Å of lithium fluoride at a vapor deposition rate of 0.2 Å / s, and then 1000 Å of aluminum at a rate of 20 Å / s. did. The inside of the vapor deposition apparatus was returned to normal pressure with nitrogen, and the substrate on which the laminate having the organic light emitting material layer of 10 mm × 10 mm was arranged was taken out.

(5-2) Covering with Inorganic Material Membrane A A mask having an opening of 13 mm × 13 mm is installed so as to cover the entire laminated body of the substrate on which the obtained laminated body is arranged, and it is inorganic by a plasma CVD method. The material film A was formed.
In the plasma CVD method, SiH ₄ gas and nitrogen gas are used as raw material gases, the respective flow rates are SiH ₄ gas 10 sccm and nitrogen gas 200 sccm, RF power is 10 W (frequency 2.45 GHz), chamber temperature is 100 ° C, and chamber. The procedure was performed under the condition that the internal pressure was 0.9 Torr.
The thickness of the formed inorganic material film A was about 1 μm.

(5-3) Formation of Resin Protective Film For the obtained substrate, the sealant for each organic EL display element obtained in Examples and Comparative Examples was applied to an inkjet ejection device (“NanoPrinter300” manufactured by Microjet Co., Ltd.). The pattern was applied to the substrate using.
Then, using an LED lamp, ultraviolet rays having a wavelength of 365 nm were irradiated at 3000 mJ / cm ² to cure the sealant for the organic EL display element to form a resin protective film.

(5-4) After forming the coating resin protective film by the inorganic material film B, a mask having an opening of 12 mm × 12 mm is installed so as to cover the entire resin protective film, and the inorganic material is subjected to plasma CVD method. A film B was formed to obtain an organic EL display element.
The plasma CVD method was carried out under the same conditions as in the above-mentioned "(5-2) Coating with inorganic material film A".
The thickness of the formed inorganic material film B was about 1 μm.

(5-5) Quenching State of Organic EL Display Element After exposing the obtained organic EL display element for 100 hours in an environment of temperature 85 ° C. and humidity 85%, a voltage of 3 V is applied to the organic EL display element. The light emission state (presence or absence of dark spots and quenching around the pixels) was visually observed. "◎" when there is no dark spot or peripheral quenching and uniform emission, "○" when there is no dark spot or peripheral quenching but a slight decrease in brightness is observed, and when dark spot or peripheral quenching is observed. Was “Δ”, and the case where the non-quenching portion was significantly enlarged was regarded as “x”, and the light emitting state of the organic EL display element was evaluated.

According to the present invention, there is provided a sealing agent for an organic EL display element capable of obtaining an organic EL display element having excellent inkjet coating property, low outgassing property, adhesion to an inorganic material film, and excellent reliability. can do.

Claims (6)

A sealing agent for an organic EL display element containing a polymerizable compound, a polymerization initiator, and a surface modifier .
The polymerizable compound contains a monofunctional oxetane compound and a polyfunctional oxetane compound, and contains.
The content of the monofunctional oxetane compound in 100 parts by weight of the polymerizable compound is 20 parts by weight or more and 35 parts by weight or less, and the content of the polyfunctional oxetane compound is 25 parts by weight or more and 40 parts by weight or less. can be,
The viscosity at 25 ° C. is 80 mPa · s or less, and the surface tension at 25 ° C. is 20 mN / m or more and 30 mN / m or less .
Used for application by inkjet method
A sealing agent for organic EL display elements. The organic EL according to claim 1 , wherein the content ratio of the monofunctional oxetane compound and the polyfunctional oxetane compound is, in terms of weight ratio, monofunctional oxetane compound: polyfunctional oxetane compound = 5: 3 to 5: 9. Sealant for display elements. The sealant for an organic EL display element according to claim 1 or 2 , wherein the polymerizable compound contains a cycloalkene oxide type alicyclic epoxy compound. The sealant for an organic EL display element according to claim 3 , wherein the content of the cycloalkene oxide type alicyclic epoxy compound in 100 parts by weight of the polymerizable compound is 15 parts by weight or more and 30 parts by weight or less. The sealant for an organic EL display element according to claim 1, 2, 3 or 4 , wherein the polymerizable compound contains an alkyl polyol type epoxy compound. The sealing agent for an organic EL display element according to claim 5 , wherein the content of the alkyl polyol type epoxy compound in 100 parts by weight of the polymerizable compound is 5 parts by weight or more and 30 parts by weight or less.