JP2023099366A - Sealing agent for organic el display element - Google Patents

Abstract

To provide a sealing agent for an organic EL display element which can be easily applied by an inkjet method, is excellent in low outgassing property, and can obtain an organic EL display element excellent in reliability.SOLUTION: A sealing agent for an organic EL display element containing a polymerizable compound and a polymerization initiator includes a compound having a hydrophilic functional group, the hydrophilic functional group value of the compound having the hydrophilic functional group is 0.003 mol/g or more and 0.02 mol/g or less and the viscosity of the entire sealing agent for the organic EL display element at 25°C is 80 mPa s or less.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a sealant for an organic EL display element, which can be easily applied by an ink jet method, has excellent low outgassing properties, and can provide an organic EL display element having excellent reliability.

An organic electroluminescence (hereinafter also referred to as “organic EL”) display element has a laminate structure in which an organic light-emitting material layer is sandwiched between a pair of electrodes facing each other, and light is emitted from one of the electrodes to the organic light-emitting material layer. When electrons are injected and holes are injected from the other electrode, the electrons and holes combine in the organic light-emitting material layer to emit light. 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 at a low DC voltage. has the advantage of

Organic light-emitting material layers and electrodes that constitute an organic EL display element have a problem that their characteristics are likely to deteriorate due to moisture, oxygen, and the like. Therefore, in order to obtain a practical organic EL display device, it is necessary to isolate the organic light-emitting material layer and the electrodes from the atmosphere to prolong the life of the device. Patent Document 1 discloses a method of sealing an organic light-emitting material layer and an electrode of an organic EL display element 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 the internal stress of the silicon nitride film from pressing the organic layer and the electrode.

In the method of sealing with a silicon nitride film disclosed in Patent Document 1, when forming the silicon nitride film, the organic light emission may be affected by the unevenness of the surface of the organic EL display element, the adhesion of foreign matter, the occurrence of cracks due to internal stress, or the like. Complete coverage of material layers and electrodes may not be possible. If the silicon nitride film is incompletely covered, moisture will enter the organic light-emitting material layer through the silicon nitride film.
Patent Documents 2 to 4 disclose a method of laminating an inorganic material film and a resin film as a method for preventing moisture from penetrating into an organic light-emitting material layer. However, the methods disclosed in Patent Documents 2 and 3 use a vacuum vapor deposition method to form a resin film, so there are problems such as the need for a large-scale apparatus and the possibility of contamination by foreign matter. was there. In the method disclosed in Patent Document 4, since the resin film is formed by screen printing, it is difficult to form a thin film, and there is a risk of contamination by foreign matter due to a screen plate or squeegee. I had a problem.

Another method for forming a resin film is a method using an inkjet method. By using the inkjet method, a resin film can be formed uniformly at high speed. However, when the sealing agent is made to have a low viscosity in order to be suitable for coating by the inkjet method, outgassing occurs or cracks occur in the inorganic material film, resulting in insufficient sealing. There is a problem that the organic EL display element becomes inferior in reliability.

JP-A-2000-223264 Japanese Patent Publication No. 2005-522891 Japanese Patent Application Laid-Open No. 2001-307873 JP 2012-190612 A

An object of the present invention is to provide a sealant for an organic EL display device that can be easily applied by an ink jet method, has excellent low outgassing properties, and can provide an organic EL display device with excellent reliability. and

The present invention 1 is a sealant for an organic EL display device containing a polymerizable compound and a polymerization initiator, which contains a compound having a hydrophilic functional group, and the hydrophilicity of the compound having a hydrophilic functional group. A sealant for an organic EL display element having a functional group value of 0.003 mol/g or more and 0.02 mol/g or less, and a viscosity of the whole sealant for an organic EL display element at 25°C of 80 mPa·s or less. .
The present invention 2 is a sealant for an organic EL display device that contains a polymerizable compound and a polymerization initiator and is used for coating by an inkjet method, the sealing agent containing a compound having a hydrophilic functional group, the hydrophilic The sealing agent for an organic EL display device, wherein the compound having a functional group has a hydrophilic functional group value of 0.003 mol/g or more and 0.02 mol/g or less.
The present invention will be described in detail below. Incidentally, matters common to the sealing agent for organic EL display elements of the present invention 1 and the sealing agent for organic EL display elements of the present invention 2 are described as "the sealing agent for organic EL display elements of the present invention". do.

The present inventors have found that by intentionally using a compound having a hydrophilic functional group, which is generally not preferred to be used in sealants for organic EL display devices from the viewpoint of preventing moisture permeability, it is possible to easily The inventors have found that it is possible to obtain an organic EL display element that can be coated, has excellent low outgassing properties, and has excellent reliability, and have completed the present invention.

The sealant for organic EL display elements of the present invention contains a compound having a hydrophilic functional group. By containing the above compound having a hydrophilic functional group, the sealant for an organic EL display element of the present invention can be easily applied by an inkjet method, has excellent low outgassing properties, and has excellent reliability. An organic EL display element can be obtained.

The hydrophilic functional group value of the compound having the hydrophilic functional group has a lower limit of 0.003 mol/g and an upper limit of 0.02 mol/g. When the hydrophilic functional group value of the compound having a hydrophilic functional group is 0.003 mol/g or more, the sealant for an organic EL display device of the present invention is excellent in inkjet applicability. Since the hydrophilic functional group value of the compound having a hydrophilic functional group is 0.02 mol/g or less, the cured product of the sealant for an organic EL display device of the present invention has excellent moisture permeability prevention properties. Become. The preferred lower limit of the hydrophilic functional group value of the compound having the hydrophilic functional group is 0.004 mol/g, the preferred upper limit is 0.015 mol/g, and the more preferred upper limit is 0.012 mol/g.
In addition, in this specification, the hydrophilic functional group value is a value calculated by the following formula.
Hydrophilic functional group value (mol/g) = (number of hydrophilic functional groups in 1 molecule of compound having hydrophilic functional group)/(molecular weight of compound having hydrophilic functional group)
Further, the sealant for an organic EL display element of the present invention contains a compound having a hydrophilic functional group and a hydrophilic functional group value of 0.003 mol/g or more and 0.02 mol/g or less. If so, it may contain a compound having a hydrophilic functional group and a hydrophilic functional group value of less than 0.003 mol/g or more than 0.02 mol/g, as long as the object of the present invention is not impaired. . Hereinafter, unless otherwise specified, the compounds having a hydrophilic functional group have a hydrophilic functional group and have a hydrophilic functional group value of 0.003 mol/g or more and 0.02 mol. /g or less.

In the compound having a hydrophilic functional group, at least one hydrophilic functional group selected from the group consisting of a hydroxyl group, an amino group, and a carboxyl group is selected from the viewpoint of the wettability of the sealant for an organic EL display element to be obtained. It preferably has a seed, more preferably has a hydroxyl group and/or a carboxyl group, and most preferably has a hydroxyl group from the viewpoint of storage stability.

The compound having a hydrophilic functional group may be a polymerizable compound having a polymerizable functional group (hereinafter also referred to as a "polymerizable compound having a hydrophilic functional group"), or may be polymerized It may be one that does not have a hydrophilic functional group and is not included in the polymerizable compound (hereinafter also referred to as "non-polymerizable compound having a hydrophilic functional group"). Among them, polymerizable compounds having a hydrophilic functional group are preferred from the viewpoint of further improving inkjet applicability and low outgassing properties. In particular, an epoxy compound or an oxetane compound having a hydroxyl group as a hydrophilic functional group is preferred.

The polymerizable compound having the hydrophilic functional group will be described later.
Examples of the non-polymerizable compound having a hydrophilic functional group include a non-polymerizable compound having a hydroxyl group, a non-polymerizable compound having a carboxyl group, and a non-polymerizable compound having an amino group.

Examples of non-polymerizable compounds having a hydroxyl group include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, hexaethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, phenyl glycol, and benzyl glycol. etc.

Examples of non-polymerizable compounds having a carboxyl group include aliphatic carboxylic acids and aromatic carboxylic acids.
Examples of the aliphatic carboxylic acids include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, 2-ethylhexanoic acid, undecylic acid, lauric acid, tridecylic acid, Myristic acid, pentadecyl acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, heptacosanoic acid, montanic acid, melisic acid and the like.
Examples of the aromatic carboxylic acid include benzoic acid and toluic acid.

Examples of non-polymerizable compounds having an amino group include aliphatic amines and aromatic amines.
Examples of the aliphatic amines include ethylenediamine, diethylenetriamine, triethylenetetramine, hexamethylenediamine, isophoronediamine, menthanediamine, 4,4′-diaminodicyclohexylmethane and the like.
Examples of the aromatic amine include m-xylylenediamine, diaminodiphenylmethane, m-phenylenediamine and the like.

Among them, tripropylene glycol is preferable as the non-polymerizable compound having a hydroxyl group.

A preferred lower limit of the content of the compound having a hydrophilic functional group is 1 part by weight, and a preferred upper limit is 50 parts by weight, based on a total of 100 parts by weight of the compound having a hydrophilic functional group and the polymerizable compound. When the content of the compound having a hydrophilic functional group is 1 part by weight or more, the resulting sealant for organic EL display elements is superior in ink-jet applicability. When the content of the compound having a hydrophilic functional group is 50 parts by weight or less, the obtained sealant for an organic EL display device has excellent moisture permeation resistance as a cured product. A more preferable lower limit of the content of the compound having a hydrophilic functional group in the whole sealant for an organic EL display element of the present invention is 10 parts by weight, and a more preferable upper limit thereof is 30 parts by weight.
In addition, the above-mentioned "total of the compound having a hydrophilic functional group and the polymerizable compound" means the following. That is, when only the polymerizable compound having the hydrophilic functional group is contained as the compound having the hydrophilic functional group, the "polymerizable compound having a hydrophilic functional group and the polymerizable compound having no hydrophilic functional group means the sum of In addition, when only the non-polymerizable compound having the hydrophilic functional group is contained as the compound having the hydrophilic functional group, the term "non-polymerizable compound having a hydrophilic functional group and polymerization not having a hydrophilic functional group "total with sexual compounds". Furthermore, when containing a polymerizable compound having a hydrophilic functional group and a non-polymerizable compound having a hydrophilic functional group as the compound having a hydrophilic functional group, "a polymerizable compound having a hydrophilic functional group and "total of a non-polymerizable compound having a hydrophilic functional group and a polymerizable compound having no hydrophilic functional group".
The "polymerizable compound having no hydrophilic functional group" means a polymerizable compound that does not have a hydrophilic functional group among the polymerizable compounds described later.

The sealant for organic EL display elements of the present invention contains a polymerizable compound. As described above, the polymerizable compound preferably contains the polymerizable compound having the hydrophilic functional group.

As the polymerizable compound, a cationically polymerizable compound or a radically polymerizable compound can be used. Among them, cationically polymerizable compounds are preferred.

Examples of the cationic polymerizable compound include epoxy compounds, oxetane compounds, and vinyl ether compounds. Among them, an epoxy compound or an oxetane compound is preferable, and an epoxy compound having a hydroxyl group as a hydrophilic functional group or an oxetane compound having a hydroxyl group as a hydrophilic functional group is more preferable.

Examples of the epoxy compound include glycidol, epoxy alcohol, 1,5-hexadiene diepoxide, 1,7-octadiene diepoxide, 1,9-decadiene diepoxide, bisphenol A type epoxy compound, and bisphenol E type epoxy compound. , bisphenol F type epoxy compound, bisphenol S type epoxy compound, bisphenol O type epoxy compound, 2,2'-diallyl bisphenol A type epoxy compound, cycloalkene oxide type alicyclic epoxy compound, hydrogenated bisphenol type epoxy compound, propylene oxide Added bisphenol A type epoxy compound, resorcinol type epoxy compound, biphenyl type epoxy compound, sulfide type epoxy compound, diphenyl ether type epoxy compound, dicyclopentadiene type epoxy compound, naphthalene type epoxy compound, phenol novolac type epoxy compound, ortho-cresol novolak type epoxy compounds, dicyclopentadiene novolak type epoxy compounds, biphenyl novolak type epoxy compounds, naphthalenephenol novolak type epoxy compounds, glycidylamine type epoxy compounds, alkylpolyol type epoxy compounds, rubber modified epoxy compounds, glycidyl ester compounds, and the like. Among them, glycidol (e.g., Epiol OH (manufactured by NOF Corporation)), epoxy alcohol (e.g., EOA (manufactured by Kuraray Co., Ltd.)), and the like are preferable as the epoxy compound that serves as a polymerizable compound having a hydrophilic functional group. Examples of the epoxy compound which is a polymerizable compound having no hydrophilic functional group include 3,4,3′,4′-diepoxybicyclohexane, 3′,4′-epoxycyclohexylmethyl-3,4- Preferred are cycloalkene oxide type alicyclic epoxy compounds such as epoxycyclohexanecarboxylate and 1,7-octadiene diepoxide.

Examples of the oxetane compounds include phenoxymethyloxetane, 3-ethyl-3-hydroxymethyloxetane, 3-ethyl-3-(4-hydroxybutyl)oxymethyloxetane, 3-ethyl-3-methacryloxymethyloxetane, 3 -ethyl-3-(phenoxymethyl)oxetane, 3-ethyl-3-((2-ethylhexyloxy)methyl)oxetane, 3-ethyl-3-((3-(triethoxysilyl)propoxy)methyl)oxetane, 3 -ethyl-3-(((3-ethyloxetan-3-yl)methoxy)methyl)oxetane, oxetanylsilsesquioxane, phenol novolak oxetane, 1,4-bis(((3-ethyl-3-oxetanyl)methoxy) ) methyl) benzene and the like. Among them, 3-ethyl-3-hydroxymethyloxetane and 3-ethyl-3-(4-hydroxybutyl)oxymethyloxetane are preferable as the oxetane compound that becomes a polymerizable compound having a hydrophilic functional group. Further, as the oxetane compound which is a polymerizable compound having no hydrophilic functional group, 3-ethyl-3-methacryloxymethyloxetane, 3-ethyl-3-(((3-ethyloxetan-3-yl) Methoxy)methyl)oxetane is preferred.

Examples of the vinyl ether compound include 2-hydroxyethyl vinyl ether, benzyl vinyl ether, cyclohexanedimethanol monovinyl ether, dicyclopentadiene vinyl ether, 1,4-butanediol divinyl ether, cyclohexanedimethanol divinyl ether, diethylene glycol divinyl ether, and triethylene glycol. divinyl ether, dipropylene glycol divinyl ether, tripropylene glycol divinyl ether and the like. Among them, 2-hydroxyethyl vinyl ether is preferable as the vinyl ether compound that becomes the polymerizable compound having the hydrophilic functional group, and cyclohexanedimethanol is the vinyl ether compound that becomes the polymerizable compound having no hydrophilic functional group. Divinyl ether is preferred.

A (meth)acrylic compound is preferable as the radically polymerizable compound.
The (meth)acrylic compound may be a monofunctional (meth)acrylic compound or a polyfunctional (meth)acrylic compound. It may be used in combination with an acrylic compound.
In the present specification, the above "(meth)acryl" means acrylic or methacryl, the above "(meth)acrylic compound" means a compound having a (meth)acryloyl group, the above "(meth) "Acryloyl" means acryloyl or methacryloyl.

From the viewpoint of low outgassing, the monofunctional (meth)acrylic compound preferably has a cationic polymerizable group.
Examples of the cationic polymerizable group include vinyl ether group, epoxy group, oxetanyl group, allyl ether group, vinyl group and hydroxyl group.

Specific examples of the monofunctional (meth)acrylic compounds include 2-hydroxyethyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, glycidyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, ) acrylate glycidyl ether, 2-(2-vinyloxyethoxy)ethyl (meth)acrylate, 3-ethyl-3-(meth)acryloxymethyloxetane, allyl (meth)acrylate, methoxydiethylene glycol (meth)acrylate, methoxytri Ethylene glycol (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, ethoxytriethylene glycol (meth) acrylate, 2-(2-vinyloxyethoxy) ethyl (meth) acrylate, 2-(meth) acryloyloxyethyl succinic acid, etc. mentioned. Among them, 2-hydroxyethyl (meth)acrylate and 2-(meth)acryloyloxyethyl succinic acid are preferable as the monofunctional (meth)acrylic compound that serves as a polymerizable compound having a hydrophilic functional group. 2-(2-vinyloxyethoxy)ethyl (meth)acrylate is preferable as the monofunctional (meth)acrylic compound which is a polymerizable compound having no hydrophilic functional group.
In addition, in this specification, the above-mentioned "(meth)acrylate" means acrylate or methacrylate.

When the polymerizable compound contains the monofunctional (meth) acrylic compound, the preferred lower limit of the content of the monofunctional (meth) acrylic compound in 100 parts by weight of the polymerizable compound is 20 parts by weight, and the preferred upper limit is 80. weight part. When the content of the monofunctional (meth)acrylic compound is within this range, the resulting sealant for organic EL display elements is excellent in low outgassing properties. A more preferable lower limit for the content of the monofunctional (meth)acrylic compound is 30 parts by weight, and a more preferable upper limit is 60 parts by weight.

The polyfunctional (meth)acrylic compound preferably has a polyoxyalkylene skeleton in its main chain from the viewpoint of inkjet applicability and the like.
The polyoxyalkylene skeleton preferably has 2 to 6 consecutive oxyalkylene units.
Examples of the oxyalkylene units constituting the polyoxyalkylene skeleton include oxyethylene units and oxypropylene units.

From the viewpoint of inkjet applicability, the polyfunctional (meth)acrylic compound preferably has a structure with few branched carbon chains, and more preferably a linear structure.

Specific examples of the polyfunctional (meth)acrylic compound include diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, and dipropylene glycol di(meth)acrylate. , tripropylene glycol di(meth)acrylate, tetrapropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol triacrylate and the like. Among them, pentaerythritol triacrylate is preferable as the polyfunctional (meth)acrylic compound that serves as a polymerizable compound having a hydrophilic functional group. Tetraethylene glycol di(meth)acrylate and trimethylolpropane tri(meth)acrylate are preferable as the polyfunctional (meth)acrylic compound which is a polymerizable compound having no hydrophilic functional group.

When the polymerizable compound contains the polyfunctional (meth) acrylic compound, the preferred lower limit of the content of the polyfunctional (meth) acrylic compound in 100 parts by weight of the polymerizable compound is 20 parts by weight, and the preferred upper limit is 80. weight part. When the content of the polyfunctional (meth)acrylic compound is within this range, the resulting sealant for organic EL display devices is superior in inkjet applicability. A more preferable lower limit for the content of the polyfunctional (meth)acrylic compound is 30 parts by weight, and a more preferable upper limit is 60 parts by weight.

When the monofunctional (meth)acrylic compound and the polyfunctional (meth)acrylic compound are used in combination, the content ratio of the monofunctional (meth)acrylic compound and the polyfunctional (meth)acrylic compound is the weight ratio. , monofunctional (meth)acrylic compound:polyfunctional (meth)acrylic compound=7:3 to 3:7. By setting the content ratio of the monofunctional (meth)acrylic compound and the polyfunctional (meth)acrylic compound within this range, the obtained sealant for an organic EL display device is made to have excellent inkjet applicability. can be done. The content ratio of the monofunctional (meth)acrylic compound and the polyfunctional (meth)acrylic compound is, in terms of weight ratio, monofunctional (meth)acrylic compound:polyfunctional (meth)acrylic compound=6:4 to 4:6. is more preferable.

The sealant for organic EL display elements of the present invention contains a polymerization initiator.
As the polymerization initiator, a photocationic polymerization initiator, a thermal cationic polymerization initiator, a photoradical polymerization initiator, and a thermal radical polymerization initiator are preferably used depending on the type of the polymerizable compound to be used.

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

Examples of the anion portion of the ionic photoacid-generating photocationic polymerization initiator include BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , or (BX ₄ ) ⁻ (where X is at least two represents a phenyl group substituted with fluorine or a trifluoromethyl group).
Examples of the ionic photoacid-generating photocationic polymerization initiator include aromatic sulfonium salts, aromatic iodonium salts, aromatic diazonium salts, aromatic ammonium salts, (2,4-cyclo pentadien-1-yl)((1-methylethyl)benzene)-Fe salts and the like.

Examples of the aromatic sulfonium salts include bis(4-(diphenylsulfonio)phenyl)sulfide bishexafluorophosphate, bis(4-(diphenylsulfonio)phenyl)sulfide bishexafluoroantimonate, bis(4-( diphenylsulfonio)phenyl)sulfide bistetrafluoroborate, bis(4-(diphenylsulfonio)phenyl)sulfidetetrakis(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-( 2-hydroxyethoxy))phenylsulfonio)phenyl)sulfide bis tetrafluoroborate, bis(4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl)sulfide tetrakis(pentafluorophenyl)borate, tris (4-(4-acetylphenyl)thiophenyl)sulfonium tetrakis(pentafluorophenyl)borate and the like.

Examples of the aromatic iodonium salts include diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, diphenyliodonium tetrafluoroborate, diphenyliodonium tetrakis(pentafluorophenyl)borate, bis(dodecylphenyl)iodonium hexafluorophosphate, bis (dodecylphenyl)iodonium 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.

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

Examples of the aromatic ammonium salts include 1-benzyl-2-cyanopyridinium hexafluorophosphate, 1-benzyl-2-cyanopyridinium hexafluoroantimonate, 1-benzyl-2-cyanopyridinium tetrafluoroborate, 1-benzyl -2-cyanopyridinium tetrakis(pentafluorophenyl)borate, 1-(naphthylmethyl)-2-cyanopyridinium hexafluorophosphate, 1-(naphthylmethyl)-2-cyanopyridinium hexafluoroantimonate, 1-(naphthylmethyl) -2-cyanopyridinium tetrafluoroborate, 1-(naphthylmethyl)-2-cyanopyridinium tetrakis(pentafluorophenyl)borate and the like.

Examples of the (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe salt include (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene )-Fe(II) hexafluorophosphate, (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe(II) hexafluoroantimonate, (2,4-cyclopentadiene-1 -yl)((1-methylethyl)benzene)-Fe(II) tetrafluoroborate, (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe(II) tetrakis(penta fluorophenyl)borate and the like.

Examples of the nonionic photoacid-generating photocationic polymerization initiator include nitrobenzyl esters, sulfonic acid derivatives, phosphoric acid esters, phenolsulfonic acid esters, diazonaphthoquinone, and N-hydroxyimide sulfonates.

Examples of 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, a photocationic polymerization initiator manufactured by ADEKA, A photocationic polymerization initiator manufactured by 3M, a photocationic polymerization initiator manufactured by BASF, a photocationic polymerization initiator manufactured by Rhodia, and the like can be mentioned.
Examples of the photocationic polymerization initiator manufactured by Midori Kagaku Co., Ltd. include DTS-200 and the like.
Examples of photo cationic polymerization initiators manufactured by Union Carbide include UVI6990 and UVI6974.
Examples of photo cationic polymerization initiators manufactured by ADEKA include SP-150 and SP-170.
Examples of photo cationic polymerization initiators manufactured by 3M include FC-508 and FC-512.
Examples of photo cationic polymerization initiators manufactured by BASF include IRGACURE261 and IRGACURE290.
Examples of the photo cationic polymerization initiator manufactured by Rhodia include PI2074.

The thermal cationic polymerization initiator has an anion moiety of BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , or (BX ₄ ) ⁻ (where X is substituted with at least two fluorine or trifluoromethyl groups). sulfonium salts, phosphonium salts, ammonium salts, etc., composed of a phenyl group represented by a phenyl group. Among them, sulfonium salts and ammonium salts are preferred.

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

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

Examples of the ammonium salts include dimethylphenyl(4-methoxybenzyl)ammonium hexafluorophosphate, dimethylphenyl(4-methoxybenzyl)ammonium hexafluoroantimonate, 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.

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

Examples of the radical photopolymerization initiator include benzophenone-based compounds, acetophenone-based compounds, acylphosphine oxide-based compounds, titanocene-based compounds, oxime ester-based compounds, benzoin ether-based compounds, benzyl, and thioxanthone-based compounds.

Examples of commercially available radical photopolymerization initiators include radical photopolymerization initiators manufactured by BASF Corporation and radical photopolymerization initiators manufactured by Tokyo Chemical Industry Co., Ltd.
Examples of photoradical polymerization initiators manufactured by BASF include IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACURE OXE01, and Lucirin TPO.
Examples of the radical photopolymerization initiator manufactured by Tokyo Kasei Kogyo Co., Ltd. include benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether.

Examples of the thermal radical polymerization initiator include those composed of azo compounds, organic peroxides, and the like.
Examples of the azo compounds include 2,2′-azobis(2,4-dimethylvaleronitrile), azobisisobutyronitrile and the like.
Examples of the organic peroxide include benzoyl peroxide, ketone peroxide, peroxyketal, hydroperoxide, dialkyl peroxide, peroxyester, diacyl peroxide, and peroxydicarbonate.

Examples of commercially available thermal radical polymerization initiators include VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS-1001, and V-501 (all of which are manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.). made) 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 sealant for organic EL display devices has excellent curability. When the content of the polymerization initiator is 10 parts by weight or less, the curing reaction of the resulting sealant for an organic EL display element does not become too fast, the workability is improved, and the cured product is more uniform. can be A more preferable lower limit to the content of the polymerization initiator is 0.05 parts by weight, and a more preferable upper limit is 5 parts by weight.

The sealant for organic EL display elements of the present invention may contain a sensitizer. The sensitizer serves to further improve the polymerization initiation efficiency of the polymerization initiator and further accelerate the curing reaction of the sealant for an organic EL display device of the present invention.

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

The content of the sensitizer has a preferable lower limit of 0.01 parts by weight and a preferable upper limit of 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 exhibited more. When the content of the sensitizer is 3 parts by weight or less, light can be transmitted to a deep portion without excessive absorption. A more preferable lower limit of the content of the sensitizer is 0.1 part by weight, and a more preferable upper limit is 1 part by weight.

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

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

The content of the silane coupling agent has a preferable lower limit of 0.1 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 silane coupling agent is within this range, the effect of improving adhesiveness while suppressing bleeding out of excess silane coupling agent is excellent. A more preferable lower limit to the content of the silane coupling agent is 0.5 parts by weight, and a more preferable upper limit is 5 parts by weight.

The sealant for an organic EL display element of the present invention may further contain a surface modifier within a range not impairing the object of the present invention. By containing the surface modifier, the sealant for an organic EL display element of the present invention can be provided with flatness of the coating film.
Examples of the surface modifier include surfactants and leveling agents.

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

The sealant for an organic EL display element of the present invention may contain a solvent for the purpose of viscosity adjustment, etc., but the remaining solvent causes problems such as deterioration of the organic light-emitting material layer and generation of outgassing. Therefore, it is preferable that the solvent is not contained or the solvent content is 0.05% by weight or less.

Further, the sealant for an organic EL display device 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

As a method for producing the sealant for an organic EL display element of the present invention, for example, a mixer is used to mix a polymerizable compound having a hydrophilic functional group or a non-polymerizable compound having a hydrophilic functional group with a hydrophilic For example, a method of mixing a polymerizable compound having no functional group, a polymerization initiator, and an additive such as a silane coupling agent to be added as necessary.
Examples of the mixer include a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader, and three rolls.

The upper limit of the viscosity at 25° C. of the sealant for an organic EL display device of the present invention 1 is 80 mPa·s. When the viscosity is 80 mPa·s or less, the sealant for an organic EL display device of the present invention 1 is excellent in inkjet applicability. A preferable upper limit of the viscosity of the sealant for organic EL display elements of the present invention 1 is 60 mPa·s, and a more preferable upper limit is 20 mPa·s.
Moreover, the preferable lower limit of the viscosity of the sealant for organic EL display elements of the present invention 1 is 5 mPa·s, and the more preferable lower limit is 8 mPa·s.
In this specification, the viscosity means a value measured using an E-type viscometer under conditions of 25° C. and 100 rpm.

The preferred upper limit of the viscosity at 25° C. of the sealant for organic EL display elements of the second invention is 80 mPa·s. When the viscosity is 80 mPa·s or less, the sealant for an organic EL display device of the present invention 2 is excellent in inkjet applicability. A more preferable upper limit of the viscosity of the sealant for an organic EL display device of the second invention is 60 mPa·s, and a more preferable upper limit is 20 mPa·s.
The preferred lower limit of the viscosity of the sealant for organic EL display elements of the second invention is 5 mPa·s, and the more preferred lower limit is 8 mPa·s.

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

The preferred lower limit of the light transmittance of the cured product of the sealant for organic EL display elements of the present invention to light having a wavelength of 420 nm is 90%. When the light transmittance is 90% or more, the obtained organic EL display element has excellent optical properties. A more preferable lower limit of the light transmittance is 95%.
The light transmittance can be measured using a spectrophotometer (eg, "U-3000" manufactured by Hitachi Ltd.). In addition, the cured product used for measuring the light transmittance and the moisture permeability and water content described later can be obtained by, for example, 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 sealant for an organic EL display element of the present invention has a moisture permeability of 100 g/m at a thickness of 100 μm, which is 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 deterioration of the organic light-emitting material layer due to moisture in the cured product is excellent, and the obtained organic EL display device is excellent in reliability.

The sealant for an organic EL display element of the present invention preferably has a moisture 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 excellent, and the obtained organic EL display device is excellent in reliability. becomes. A more preferable upper limit of the moisture content of the cured product is 0.3%.
Examples of the method for measuring the moisture content include a method of determining by the Karl Fischer method in accordance with JIS K 7251, and a method of determining weight increase after water absorption in accordance with JIS K 7209-2.

A method for producing an organic EL display element using the sealant for an organic EL display element of the present invention includes, 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. and a step of curing the applied sealant for an organic EL display element by light irradiation and/or heating.

In the step of applying the sealant for organic EL display elements of the present invention to a base material, the sealant for organic EL display elements 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. You can apply it. The shape of the sealing portion of the sealing agent for an organic EL display element of the present invention formed by coating is not particularly limited as long as it is a shape capable of protecting the laminate having the organic light-emitting material layer from the outside air. It may be a shape that completely covers the body, a closed pattern may be formed in the peripheral portion of the laminate, or a pattern having a shape with a partial opening provided in the peripheral portion of the laminate. may be formed.

When the sealant for organic EL display elements of the present invention is cured by light irradiation, the sealant for organic EL display elements of the present invention has a wavelength of 300 nm or more and 400 nm or less and a wavelength of 300 mJ/cm ² or more and 3000 mJ/cm ² or less. It can be suitably cured by irradiating the integrated light amount.

Examples of light sources used for light irradiation include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, excimer lasers, chemical lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, sodium lamps, halogen lamps, and xenon. lamps, LED lamps, fluorescent lamps, sunlight, electron beam irradiation devices, and the like. 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 radical photopolymerization initiator and the cationic photopolymerization initiator.

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

The cured product obtained by the step of curing the sealant for organic EL display elements 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 consist of one layer, or may be a laminate of a plurality of types of layers. Moreover, the inorganic material film and the resin film made of the sealant for an organic EL display element of the present invention may be alternately repeated to coat the laminate.

The method for producing the organic EL display element includes a step of bonding a base material coated with the sealant for an organic EL display element of the present invention (hereinafter also referred to as "one base material") and the other base material. may have.
The base material to which the sealant for an organic EL display element of the present invention is applied (hereinafter also referred to as "one base material") may be a base material on which a laminate having an organic light-emitting material layer is formed. , it may be a substrate on which the laminate is not formed.
When the one base material is a base material on which the laminate is not formed, when the other base material is bonded, the one base material of the present invention is attached to the one base material so that the laminate can be protected from the outside air. The organic EL display element sealant of the above may be applied. That is, it is applied to the entire surface of the position of the laminate when the other base material is attached, or the position of the laminate when the other base material is attached is completely covered. A closed pattern of the encapsulant portion may be formed in a shape that fits within.

The step of curing the organic EL display element sealing agent by light irradiation and/or heating may be performed before the step of bonding the one base material and the other base material together, or You may carry out after the process of bonding a base material and the said other base material together.
When the step of curing the organic EL display element sealant by light irradiation and/or heating is performed before the step of bonding the one substrate and the other substrate together, the organic EL display of the present invention It is preferable that the element sealant has a pot life of 1 minute or more, which is the time from irradiation with light and/or heating until the curing reaction progresses and adhesion becomes impossible. When the pot life is 1 minute or longer, a higher adhesive strength can be obtained without excessive curing before bonding the one base material and the other base material together.

In the step of bonding the one base material and the other base material together, the method of bonding the one base material and the other base material together is not particularly limited, but bonding under a reduced pressure atmosphere is preferred.
A preferable lower limit of the degree of vacuum under the reduced pressure atmosphere is 0.01 kPa, and a preferable upper limit thereof is 10 kPa. Since the degree of vacuum under the reduced-pressure atmosphere is within this range, the one substrate and the other substrate can be separated from each other 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. Air bubbles in the sealant for an organic EL display element of the present invention can be removed more efficiently when the material is attached.

According to the present invention, there is provided a sealant for an organic EL display device that can be easily applied by an ink jet method, has excellent low outgassing properties, and can provide an organic EL display device with excellent reliability. can be done.

EXAMPLES The present invention will be described in more detail with reference to Examples below, but the present invention is not limited to these Examples.

(Examples 1 to 13, Comparative Examples 1 to 5)
According to the compounding ratio described in Tables 1 to 3, each material is uniformly stirred and mixed at a stirring speed of 3000 rpm using a Homo Disper type stirring mixer (manufactured by Primix, "Homo Disper L type"). Sealants for organic EL display elements of Examples 1 to 13 and Comparative Examples 1 to 5 were prepared.
Each sealant for organic EL display elements obtained in Examples and Comparative Examples was measured using an E-type viscometer (manufactured by Toki Sangyo Co., Ltd., "VISCOMETER TV-22") at 25°C and 100 rpm. The viscosities obtained are shown in Tables 1-3.

<Evaluation>
The sealants for organic EL display elements obtained in Examples and Comparative Examples were evaluated as follows. The results are shown in Tables 1-3.

(1) Ink jet applicability (1-1) Ink jet discharge property Each sealant for organic EL display elements obtained in Examples and Comparative Examples was applied using an ink jet discharge device ("NanoPrinter 500" manufactured by Microjet). , 1000 droplets were applied at a rate of 5 m/sec on an alkali-free glass ("AN100" manufactured by Asahi Glass Co., Ltd.) washed with alkali at a droplet volume of 30 picoliters at a pitch of 500 μm.
If the number of droplets that could not be applied was 0, "○", if the number of droplets that could not be applied was 1 or more and less than 20, "△", and could not be applied. Inkjet dischargeability was evaluated as "x" when the number of the ink was 20 or more.

(1-2) Wetting and spreading property Each of the sealants for organic EL display elements obtained in Examples and Comparative Examples was applied to 30 picoliters of liquid using an inkjet ejection device (manufactured by Microjet, "NanoPrinter 500"). 1000 drops were applied at a rate of 5 m/sec at a rate of 5 m/sec on an alkali-free glass (“AN100” manufactured by Asahi Glass Co., Ltd.) washed with alkali. After the coating, it was left at 25° C. for 10 minutes, and the diameter of the droplet on the non-alkali glass was measured.
"○" when the droplet diameter is 150 μm or more, "△" when the droplet diameter is 50 μm or more and less than 150 μm, and "×" when the droplet diameter is less than 50 μm. Wet spreadability was evaluated.

(2) Low outgassing property The outgassing generated during heating of the cured products of the sealing agents for organic EL display elements obtained in Examples and Comparative Examples was measured by a gas chromatograph according to the following headspace method.
First, 100 mg of each sealing agent for organic EL display elements was applied with an applicator to a thickness of 300 μm, and then UV rays with a wavelength of 365 nm were irradiated at 3000 mJ/cm ² with an LED lamp to cure the sealing agent. Next, the obtained sealant cured product 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 outgassing property was evaluated as "○" when the generated gas was less than 300 ppm, "Δ" when it was 300 ppm or more and less than 500 ppm, and "X" when it was 500 ppm or more.

(3) Light transmittance Each sealant for organic EL display elements obtained in Examples and Comparative Examples is sandwiched between PET resin films, and sealed by irradiating 3000 mJ/cm ² of ultraviolet rays with a wavelength of 365 nm from an LED lamp. The agent was cured to prepare a sample for transmittance measurement with a thickness of 100 μm. The obtained sample for transmittance measurement was measured for light transmittance at a wavelength of 420 nm using a spectrophotometer (manufactured by Hitachi, Ltd., "U-3000").

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

(4-2) Coating with Inorganic Material Film A A mask having an opening of 13 mm × 13 mm is placed so as to cover the entire laminate on the substrate on which the obtained laminate is arranged, and the inorganic material is coated by plasma CVD. A material film A was formed.
The plasma CVD method uses SiH ₄ gas and nitrogen gas as raw material gases, with flow rates of SiH ₄ gas of 10 sccm and nitrogen gas of 200 sccm, RF power of 10 W (frequency of 2.45 GHz), chamber temperature of 100 ° C., chamber It was carried out under the condition that the internal pressure was 0.9 Torr.
The thickness of the formed inorganic material film A was about 1 μm.

(4-3) Formation of resin protective film Each sealant for organic EL display elements obtained in Examples and Comparative Examples was applied to the obtained substrate using an inkjet ejection device (“NanoPrinter 500” manufactured by Microjet). was used to pattern-coat the substrate. The sealing agents for organic EL display elements obtained in Comparative Examples 3 and 5 did not normally eject droplets from the inkjet ejection device, and a coating film could not be obtained. Therefore, the subsequent operations were not performed. .
Thereafter, an LED lamp was used to irradiate 3000 mJ/cm ² of ultraviolet rays having a wavelength of 365 nm to cure the sealant for organic EL display elements, thereby forming a resin protective film.

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

(4-5) Luminescent state of organic EL display element After exposing the obtained organic EL display element in an environment with a temperature of 85° C. and a humidity of 85% for 100 hours, a voltage of 3 V was applied to the organic EL display element. The light emission state (whether or not there are dark spots and pixel peripheral quenching) was visually observed. "○" indicates uniform emission without dark spots or peripheral extinction, "△" indicates slight decrease in luminance although there are no dark spots or peripheral extinction, and "△" indicates that dark spots or peripheral extinction is observed. The reliability of the organic EL display element was evaluated with "X".

According to the present invention, there is provided a sealant for an organic EL display device that can be easily applied by an ink jet method, has excellent low outgassing properties, and can provide an organic EL display device with excellent reliability. can be done.

Claims (8)

A sealant for an organic EL display element containing a polymerizable compound and a polymerization initiator,
containing a compound having a hydrophilic functional group, the hydrophilic functional group value of the compound having the hydrophilic functional group being 0.003 mol/g or more and 0.02 mol/g or less;
A sealant for organic EL display elements, wherein the viscosity of the whole sealant for organic EL display elements at 25°C is 80 mPa·s or less. A sealant for an organic EL display element containing a polymerizable compound and a polymerization initiator and used for coating by an inkjet method,
An organic EL display device comprising a compound having a hydrophilic functional group, wherein the hydrophilic functional group value of the compound having a hydrophilic functional group is 0.003 mol/g or more and 0.02 mol/g or less. sealant. 3. The encapsulant for an organic EL display element according to claim 1, wherein said compound having a hydrophilic functional group has at least one selected from the group consisting of a hydroxyl group, an amino group and a carboxyl group as a hydrophilic functional group. agent. 4. The sealant for an organic EL display device according to claim 3, wherein said compound having a hydrophilic functional group has a hydroxyl group as the hydrophilic functional group. 5. The sealant for an organic EL display element according to claim 1, 2, 3 or 4, wherein said compound having a hydrophilic functional group is a polymerizable compound having a hydrophilic functional group. 3. The content of the compound having a hydrophilic functional group is 1 part by weight or more and 50 parts by weight or less in a total of 100 parts by weight of the compound having a hydrophilic functional group and the polymerizable compound. , 4 or 5 for an organic EL display element. 7. The sealant for an organic EL display element according to claim 1, wherein said polymerizable compound is an epoxy compound or an oxetane compound. 8. The sealant for organic EL display elements according to claim 1, wherein the light transmittance of the cured product to light having a wavelength of 420 nm is 90% or more.