KR20220038275A - Encapsulant for organic EL display elements - Google Patents

Abstract

An object of this invention is to provide the sealing agent for organic electroluminescent display elements which is excellent in low outgassing property and applicability|paintability, and can obtain the organic electroluminescent display element excellent in light extraction efficiency.
The present invention is a sealing agent for an organic EL display device containing a cationic polymerizable compound and a cationic polymerization initiator, wherein the cationic polymerizable compound is a cycloalkenoxide type alicyclic epoxy compound, and a biphenyl skeleton and an epoxy group Or it is a sealing agent for organic electroluminescent display elements containing the compound which has an oxetanyl group.

Description

Encapsulant for organic EL display elements

This invention is excellent in low outgassing property and applicability|paintability, and also relates to the sealing agent for organic electroluminescent display elements from which the organic electroluminescent display element excellent in light extraction efficiency can be obtained.

An organic electroluminescent (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 mutually opposing electrodes, and one electrode is provided on the organic light emitting material layer. Electrons and holes are injected from the other electrode while electrons are injected from the other electrode, so that electrons and holes are combined in the organic light emitting material layer to emit light. As described above, since the organic EL display device emits light as described above, compared to a liquid crystal display device requiring a backlight, the organic EL display device has advantages such as better visibility, thinner thickness, and low DC voltage driving.

The organic light emitting material layer and electrode constituting the organic EL display element have a problem in that their properties are easily deteriorated by moisture, oxygen, or the like. Therefore, in order to obtain a practical organic electroluminescent display element, it is necessary to cut off an organic light emitting material layer and an electrode from air|atmosphere, and to aim at lengthening of life. As a method of shielding an organic light emitting material layer and an electrode from air|atmosphere, sealing an organic electroluminescent display element using a sealing agent is performed (for example, patent document 1). When sealing an organic electroluminescent display element with a sealing agent, in order to fully suppress permeation|transmission of moisture, oxygen, etc. normally, an inorganic material film called a passivation film is formed on the laminated body which has an organic light emitting material layer, and the inorganic material film A method of encapsulating the phase with an encapsulant is used.

Recently, instead of the bottom emission type organic EL display element in which light generated from the organic light emitting material layer is extracted from the side of the substrate on which the light emitting element is formed, the top emission type organic EL display in which light is extracted from the upper surface side of the organic light emitting layer Little ones are getting attention. This method has an advantage in that it has a high aperture ratio and is driven at a low voltage, which is advantageous for increasing the lifespan. In such a top emission type organic EL display element, since the upper surface side of the light emitting layer needs to be transparent, it is sealed by laminating a transparent moisture-proof substrate such as glass through a transparent sealing layer on the upper surface side of the light emitting element ( For example, Patent Document 2). However, in a top emission type organic EL display element, even when a transparent moisture-proof base material or a sealing agent having sufficiently high transparency is used, the light extraction efficiency of the light generated from the laminate is due to the refractive index difference between the electrode, the passivation film, and the sealing agent. There was a problem that there were cases when this inferior thing. Moreover, the conventional sealing agent has problems, such as a thing which generate|occur|produces an outgas and deteriorates an element, or is inferior in applicability|paintability. Moreover, in order to reduce the damage to the organic electroluminescent display element by heating, what can be hardened|cured at low temperature as an encapsulant was calculated|required.

Japanese Patent Laid-Open No. 2007-115692 Japanese Patent Laid-Open No. 2009-051980

An object of this invention is to provide the sealing agent for organic electroluminescent display elements which is excellent in low outgassing property and applicability|paintability, and can obtain the organic electroluminescent display element excellent in light extraction efficiency.

The present invention is a sealing agent for an organic EL display device containing a cationic polymerizable compound and a cationic polymerization initiator, wherein the cationic polymerizable compound is a cycloalkenoxide type alicyclic epoxy compound, and a biphenyl skeleton and an epoxy group Or it is a sealing agent for organic electroluminescent display elements containing the compound which has an oxetanyl group.

Hereinafter, the present invention will be described in detail.

MEANS TO SOLVE THE PROBLEM This inventor improved applicability|paintability by using a cycloalkenoxide type alicyclic epoxy compound as a cationically polymerizable compound for the sealing agent for organic electroluminescent display elements, and examined preventing generation|occurrence|production of an outgas. However, the encapsulant using such a cycloalkenoxide type alicyclic epoxy compound is excellent in the effect of preventing the generation of outgas, but since the refractive index difference between the electrode or the passivation film is large, the interface between the electrode or the passivation film and the encapsulant There existed a problem that the light extraction efficiency fell by the reflection in in. Then, this inventor examined using this cycloalkenoxide type alicyclic epoxy compound and the compound which has a biphenyl skeleton and an epoxy group or oxetanyl group in combination as a cationically polymerizable compound. As a result, it is excellent in low outgassing property and applicability|paintability, and it discovers that the sealing agent for organic electroluminescent display elements which can make the organic electroluminescent display element obtained into what is excellent in light extraction efficiency can be obtained, and completes this invention came to do

Moreover, when a thermal cationic polymerization initiator is used as a cationic polymerization initiator and the sealing agent for organic electroluminescent display elements of this invention is made into a thermosetting sealing agent, it becomes possible to harden easily at the low temperature of 100 degreeC or less.

The sealing agent for organic electroluminescent display elements of this invention contains a cationically polymerizable compound.

The said cationically polymerizable compound contains a cycloalkenoxide type alicyclic epoxy compound. By containing the said cycloalkenoxide type alicyclic epoxy compound, the sealing agent for organic electroluminescent display elements of this invention becomes the thing excellent in low outgassing property and applicability|paintability.

Examples of the cycloalkenoxide type alicyclic epoxy compound include 3',4'-epoxycyclohexylmethyl3,4-epoxycyclohexanecarboxylate, bis(3,4-epoxycyclohexylmethyl)ether, 1,2-Epoxy-4-(2-oxiranyl)cyclohexane of bis(3,4-epoxycyclohexan-1-ylmethyl) adipic acid, 2,2-bis(hydroxymethyl)-1-butanol Adducts, methacrylic acid [(3,4-epoxycyclohexane)-1-yl] methyl, etc. are mentioned.

As what is marketed among the said cycloalkenoxide type alicyclic epoxy compounds, Celoxide 2021P (made by Daicel), TTA26 (made by Sun Chemicals), EHPE3150 (made by Daicel), etc. are mentioned.

The minimum with preferable content of the said cycloalkenoxide type alicyclic epoxy compound in 100 weight part of total said cationically polymerizable compounds is 3 weight part, and a preferable upper limit is 45 weight part. When content of the said cycloalkenoxide type alicyclic epoxy compound is 3 weight part or more, the sealing agent for organic electroluminescent display elements obtained becomes more excellent in sclerosis|hardenability, low outgassing property, and applicability|paintability. When content of the said cycloalkenoxide type alicyclic epoxy compound is 45 weight part or less, the organic electroluminescent display element obtained becomes the thing more excellent in light extraction efficiency. A more preferable lower limit of content of the said cycloalkenoxide type alicyclic epoxy compound is 5 weight part, a more preferable upper limit is 40 weight part, and a still more preferable upper limit is 38 weight part.

The said cationically polymerizable compound contains the compound which has a biphenyl skeleton and an epoxy group or oxetanyl group. By containing the compound which has the said biphenyl skeleton and an epoxy group or oxetanyl group, the sealing agent for organic electroluminescent display elements of this invention becomes a thing with a small refractive index difference with an electrode and a passivation film, As a result, the organic electroluminescent display element obtained It becomes a thing excellent in light extraction efficiency. In addition, by containing a compound having a biphenyl skeleton and an epoxy group or an oxetanyl group, when the sealing agent for an organic EL display device of the present invention is used as a thermosetting sealing agent, it can be easily cured at a low temperature of 100 ° C. or less. do.

As the compound having a biphenyl skeleton and an epoxy group or an oxetanyl group, an epoxy compound having a biphenyl skeleton or an oxetane compound having a biphenyl skeleton may be used, and from the viewpoint of viscosity, refractive index, photocurability, etc., various biphenyl skeletons and It is possible to appropriately select a compound having an epoxy group or an oxetanyl group.

Specific examples of the compound having the biphenyl skeleton and the epoxy group or oxetanyl group include, for example, o-phenylphenol glycidyl ether, a compound represented by the following formula (1), p-phenylphenol glycidyl ether, 4,4-biphenyldiylbis(glycidylether), 4,4'-bis(glycidyloxy)-1,1'-biphenyl, 3,3',5,5'-tetramethyl-4 ,4'-bis(glycidyloxy)-1,1'-biphenyl etc. are mentioned. Especially, o-phenylphenol glycidyl ether and the compound represented by following formula (1) are preferable.

The compound which has the said biphenyl skeleton and an epoxy group or oxetanyl group may be used independently and may be used in combination of 2 or more type.

[Formula 1]

In Formula (1), n is the number of repetitions.

It is preferable that the n is a value from which the compound represented by Formula (1) satisfies the range of the oxetanyl equivalent mentioned later.

The preferable lower limit of the epoxy equivalent or oxetanyl equivalent of the compound having the biphenyl skeleton and the epoxy group or oxetanyl group is 110, and the preferable upper limit is 500. When the epoxy equivalent or oxetanyl equivalent of the compound having the biphenyl skeleton and the epoxy group or oxetanyl group is in this range, the resulting encapsulant for an organic EL display device is more excellent in adhesiveness, low outgassing property, and applicability do.

In addition, in the present specification, the epoxy equivalent or oxetanyl equivalent of the compound having the biphenyl skeleton and the epoxy group or oxetanyl group is (molecular weight of the compound having the biphenyl skeleton and the epoxy group or oxetanyl group) / (biphenyl the number of epoxy groups or oxetanyl groups in one molecule of the compound having a skeleton and an epoxy group or oxetanyl group).

The preferable lower limit of the molecular weight of the compound having the biphenyl skeleton and the epoxy group or oxetanyl group is 200, and the preferable upper limit is 1000. When the molecular weight of the compound which has the said biphenyl skeleton and an epoxy group or oxetanyl group is this range, the sealing agent for organic electroluminescent display elements obtained becomes more excellent in adhesiveness, low outgassing property, and applicability|paintability.

In the present specification, the "molecular weight" is a molecular weight obtained from the structural formula for a compound whose molecular structure is specified, but for a compound with a wide distribution of polymerization degree and for a compound with an unspecified modified site, the weight average molecular weight is used. may indicate. In addition, the said "weight average molecular weight" is a value calculated|required by polystyrene conversion by measuring using tetrahydrofuran as a solvent by gel permeation chromatography (GPC). As a column used when measuring the weight average molecular weight by polystyrene conversion by GPC, Shodex LF-804 (made by Showa Denko Co., Ltd.) etc. are mentioned, for example.

It is preferable that the compound which has the said biphenyl skeleton and an epoxy group or an oxetanyl group is liquid at 25 degreeC. When the epoxy equivalent or oxetanyl equivalent of the compound which has the said biphenyl skeleton and an epoxy group or oxetanyl group is liquid at 25 degreeC, the sealing agent for organic electroluminescent display elements obtained becomes more excellent in applicability|paintability.

As what is marketed among the compound which has the said biphenyl skeleton and an epoxy group or an oxetanyl group, OPP-EP (made by Yokkaichi Synthesis Co., Ltd.), ETERNACOLL OXBP (made by Ube Kogsan Co., Ltd.) etc. are mentioned, for example.

The minimum with preferable content of the compound which has the said biphenyl skeleton and an epoxy group or an oxetanyl group in 100 weight part of total said cationically polymerizable compounds is 30 weight part, and a preferable upper limit is 97 weight part. When content of the compound which has the said biphenyl skeleton and an epoxy group or an oxetanyl group is 30 weight part or more, the organic electroluminescent display element obtained becomes the thing excellent in light extraction efficiency. When content of the compound which has the said biphenyl skeleton and an epoxy group or an oxetanyl group is 97 weight part or less, the sealing agent for organic electroluminescent display elements obtained becomes the thing excellent in sclerosis|hardenability, low outgassing property, and applicability|paintability. A more preferable lower limit of the content of the compound having a biphenyl skeleton and an epoxy group or an oxetanyl group is 50 parts by weight, a more preferable upper limit is 90 parts by weight, and a still more preferable upper limit is 80 parts by weight.

When content of the said cycloalkenoxide type alicyclic epoxy compound is 1, ratio of content of the said biphenyl skeleton and the compound which has an epoxy group or oxetanyl group is weight ratio, A preferable lower limit is 1, and a preferable upper limit is 20. By making the ratio of the content of the biphenyl skeleton and the compound having an epoxy group or an oxetanyl group to 1 or more, the resulting sealing agent for an organic EL display element has more excellent refractive index (light extraction efficiency), and by setting it to 20 or less, curability and The refractive index becomes more excellent. A more preferable lower limit of the ratio of the content of the biphenyl skeleton and the compound having an epoxy group or an oxetanyl group is 1.3, a more preferable upper limit is 15, a more preferable lower limit is 1.4, and a still more preferable upper limit is 10.

In addition to the compound which has the said cycloalkenoxide type alicyclic epoxy compound and the said biphenyl skeleton, and an epoxy group or oxetanyl group, the said cationically polymerizable compound may contain the other cationically polymerizable compound.

As said other cationically polymerizable compound, other epoxy compounds other than the compound which has the said cycloalkenoxide type alicyclic epoxy compound and the said biphenyl skeleton, and an epoxy group or oxetanyl group, and another oxetane compound, for example. , vinyl ether compounds, and the like.

As said other epoxy compound, For example, a fluorene type epoxy compound, 1,7- octadiene diepoxide, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycyl Cydyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,6 -hexanediol diglycidyl ether, glycerin diglycidyl ether, trimethylol propane triglycidyl ether, phenyl glycidyl ether, phenylenedi glycidyl ether, etc. are mentioned.

As said other oxetane compound, 3-ethyl-3-(((3-ethyloxetan-3-yl)methoxy)methyl)oxetane, 3-ethyl-3-((2- Ethylhexyloxy)methyl)oxetane, 3-ethyl-3-((3-(triethoxysilyl)propoxy)methyl)oxetane, phenolnovolacoxetane, 1,4-bis(((3- ethyl-3-oxetanyl)methoxy)methyl)benzene and the like.

Examples of the vinyl ether compound include benzyl vinyl ether, cyclohexanedimethanol monovinyl ether, dicyclopentadiene vinyl ether, 1,4-butanediol divinyl ether, cyclohexanedimethanol divinyl ether, diethylene glycol. Divinyl ether, triethylene glycol divinyl ether, dipropylene glycol divinyl ether, tripropylene glycol divinyl ether, etc. are mentioned.

Especially, as said other cationically polymerizable compound, 3-ethyl-3-(((3-ethyloxetan-3-yl)methoxy)methyl)oxetane, 1,2:7,8-di At least one selected from the group consisting of epoxyoctane and 1,2:5,6-diepoxycyclooctane is preferable, and 3-ethyl-3-(((3-ethyloxetan-3-yl)methoxy ) methyl) oxetane is more preferable.

When the said cationically polymerizable compound contains the said other cationically polymerizable compound, the minimum with preferable content of the said other cationically polymerizable compound in 100 weight part of said cationically polymerizable compounds is 1 weight part, A preferable upper limit is 60 parts by weight. When content of said other cationically polymerizable compound is this range, the sealing agent for organic electroluminescent display elements obtained becomes the thing more excellent in adhesiveness and applicability|paintability. A more preferable minimum of content of the said other cationically polymerizable compound is 10 weight part, and a more preferable upper limit is 50 weight part, A more preferable minimum is 15 weight part, and a more preferable upper limit is 40 weight part.

Moreover, when the said cationically polymerizable compound contains the said other cationically polymerizable compound, the said cycloalkenoxide type alicyclic epoxy compound and said other cation in 100 weight part of said cationically polymerizable compounds The minimum with preferable content of the sum total of a polymeric compound is 20 weight part. When content of the total of the said cycloalkenoxide type alicyclic epoxy compound and the said other cationically polymerizable compound is 20 weight part or more, the sealing agent for organic electroluminescent display elements obtained becomes more excellent in applicability|paintability. The minimum with more preferable content of the total of the said cycloalkenoxide type alicyclic epoxy compound and the said other cationically polymerizable compound is 25 weight part.

The sealing agent for organic electroluminescent display elements of this invention contains a cationic polymerization initiator.

As said cationic polymerization initiator, a thermal cationic polymerization initiator and a photocationic polymerization initiator are mentioned. In particular, when the sealing agent for organic electroluminescent display elements of this invention uses a thermal cationic polymerization initiator as said cationic polymerization initiator, it becomes possible to harden easily at the low temperature of 100 degreeC or less.

In the thermal cationic polymerization initiator, the anion moiety is BF ₄ ^- , PF ₆ ^- , SbF ₆ ^- , or (BX ₄ ) ^- (provided that X is substituted with at least two or more fluorine or trifluoromethyl groups) phenyl group), a sulfonium salt, a phosphonium salt, an ammonium salt, a diazonium salt, an iodonium salt, etc. are mentioned. Especially, a sulfonium salt is preferable.

As said sulfonium salt, triphenylsulfonium tetrafluoroborate, triphenylsulfonium hexafluoroantimonate, etc. are mentioned.

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, dimethylphenyl (4-methoxybenzyl) Ammoniumtetrakis(pentafluorophenyl)borate, dimethylphenyl(4-methylbenzyl)ammonium hexafluorophosphate, dimethylphenyl(4-methylbenzyl)ammonium hexafluoroantimonate, dimethylphenyl(4-methylbenzyl)ammonium Hexafluorotetrakis(pentafluorophenyl)borate, methylphenyldibenzylammonium hexafluorophosphate, methylphenyldibenzylammoniumhexafluoroantimonate, methylphenyldibenzylammoniumtetrakis(pentafluorophenyl)borate, phenyltribenzyl Ammonium tetrakis (pentafluorophenyl) borate, dimethylphenyl (3,4-dimethylbenzyl) 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 trifluoro Methanesulfonic acid etc. are mentioned.

As what is marketed among the said thermal cationic polymerization initiators, the thermal cationic polymerization initiator by Sanshin Chemical Industries, Ltd., the thermal cationic polymerization initiator by King Industries, etc. are mentioned, for example.

As said Sanshin Chemical Industry Co., Ltd. product thermal cationic polymerization initiator, San-Aid SI-60, San-Aid SI-80, San-Aid SI-B3, San-Aid SI-B3A, San-Aid SI-B4 etc. are mentioned, for example. can

As a thermal cationic polymerization initiator by the said King Industries, CXC-1612, CXC-1821, etc. are mentioned, for example.

The said photocationic polymerization initiator will not be specifically limited if it generate|occur|produces a protonic acid or a Lewis acid by light irradiation, An ionic photo-acid generating type may be sufficient, and a nonionic photo-acid generating type may be sufficient as it.

As the anion moiety of the photocationic polymerization initiator of the ionic photoacid generating type, for example, BF ₄ ^- , PF ₆ ^- , SbF ₆ ^- , (BX ₄ ) ^- (provided that X is at least two or more represents a phenyl group substituted with a fluorine or trifluoromethyl group); and the like. Further, examples of the anion moiety include PF _m (C _n F _2n+1 ) _6-m ^- (wherein m is an integer of 0 or more and 5 or less, and n is an integer of 1 or more and 6 or less). there is.

As said ionic photo-acid generating type photocationic polymerization initiator, For example, the aromatic sulfonium salt, aromatic iodonium salt, aromatic diazonium salt, aromatic ammonium salt, (2,4-cyclopentadiene which has the said anion moiety) -1-yl)((1-methylethyl)benzene)-Fe salt and the like.

Examples of the aromatic sulfonium salt include bis(4-(diphenylsulfonio)phenyl)sulfidebishexafluorophosphate, bis(4-(diphenylsulfonio)phenyl)sulfidebishexafluoro Rhoantimonate, bis(4-(diphenylsulfonio)phenyl)sulfidebistetrafluoroborate, bis(4-(diphenylsulfonio)phenyl)sulfidetetrakis(pentafluorophenyl)borate , Diphenyl-4- (phenylthio) phenylsulfonium hexafluorophosphate, diphenyl-4- (phenylthio) phenylsulfonium hexafluoroantimonate, diphenyl-4- (phenylthio) phenylsulfonium tetra Fluoroborate, diphenyl-4-(phenylthio)phenylsulfoniumtetrakis(pentafluorophenyl)borate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium Tetrafluoroborate, triphenylsulfoniumtetrakis(pentafluorophenyl)borate, bis(4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl)sulfidebishexafluoro Phosphate, bis(4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl)sulfidebishexafluoroantimonate, bis(4-(di(4-(2-hydroxyl) Roxyethoxy))phenylsulfonio)phenyl)sulfidebistetrafluoroborate, bis(4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl)sulfidetetrakis( pentafluorophenyl) borate, tris(4-(4-acetylphenyl)thiophenyl)sulfoniumtetrakis(pentafluorophenyl)borate, etc. are mentioned. Among them, triarylsulfonium tetrakis(pentafluorophenyl)borates such as triphenylsulfoniumtetrakis(pentafluorophenyl)borate are preferable.

Examples of the aromatic iodonium salt include diphenyl iodonium hexafluorophosphate, diphenyl iodonium hexafluoroantimonate, diphenyl iodonium tetrafluoroborate, diphenyl iodonium tetrakis (pentafluoro Phenyl) borate, bis(dodecylphenyl)iodonium hexafluorophosphate, bis(dodecylphenyl)iodonium hexafluoroantimonate, bis(dodecylphenyl)iodoniumtetrafluoroborate, bis(dodecylphenyl) ) iodonium tetrakis (pentafluorophenyl) borate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium hexafluorophosphate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium hexafluoro Roantimonate, 4-methylphenyl-4-(1-methylethyl)phenyliodoniumtetrafluoroborate, 4-methylphenyl-4-(1-methylethyl)phenyliodoniumtetrakis(pentafluorophenyl)borate, etc. can be heard

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

Examples of the aromatic ammonium salt include 1-benzyl-2-cyanopyridinium hexafluorophosphate, 1-benzyl-2-cyanopyridinium hexafluoroantimonate, and 1-benzyl-2-cyano. Pyridinium tetrafluoroborate, 1-benzyl-2-cyanopyridinium tetrakis (pentafluorophenyl) borate, 1- (naphthylmethyl) -2-cyanopyridinium hexafluorophosphate, 1- (naph Tylmethyl) -2-cyanopyridinium hexafluoroantimonate, 1- (naphthylmethyl) -2-cyanopyridinium tetrafluoroborate, 1- (naphthylmethyl) -2-cyanopyridinium Tetrakis (pentafluorophenyl) borate, etc. are mentioned.

As the (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe salt, for example, (2,4-cyclopentadien-1-yl)((1- Methylethyl)benzene)-Fe(II) hexafluorophosphate, (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe(II) hexafluoroantimonate, ( 2,4-Cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe(II) tetrafluoroborate, (2,4-cyclopentadien-1-yl)((1-methylethyl ) benzene) -Fe(II) tetrakis (pentafluorophenyl) borate, etc. are mentioned.

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

As what is marketed among the said photocationic polymerization initiators, For example, the photocationic polymerization initiator by Midori Chemical, the photocationic polymerization initiator by Union Carbide, the photocationic polymerization initiator by the ADEKA, 3M company The photocationic polymerization initiator by manufacture, the photocationic polymerization initiator by the BASF company, the photocationic polymerization initiator by the Solvay company, the photocationic polymerization initiator by the San Apro company, etc. are mentioned.

As a photocationic polymerization initiator by the said Midori Chemical company, DTS-200 etc. are mentioned, for example.

UVI6990, UVI6974 etc. are mentioned as said Union Carbide photocationic polymerization initiator, for example.

As a photocationic polymerization initiator by the said ADEKA company, SP-150, SP-170, etc. are mentioned, for example.

As a photocationic polymerization initiator by the said 3M company, FC-508, FC-512, etc. are mentioned, for example.

As said BASF photocationic polymerization initiator, IRGACURE261, IRGACURE290, etc. are mentioned, for example.

As a photocationic polymerization initiator by the said Solvay company, PI2074 etc. are mentioned, for example.

As a photocationic polymerization initiator by the said San Apro company, CPI-100P, CPI-200K, CPI-210S etc. are mentioned, for example.

Among the cationic polymerization initiators mentioned above, the quaternary ammonium salt (henceforth "borate-type quaternary ammonium salt") whose counter anion is a borate type is used preferably.

The counter anion of the borate-based quaternary ammonium salt is preferably BF ₄ ^- or (BX ₄ ) ^- (where X represents a phenyl group substituted with at least two fluorine or trifluoromethyl groups).

As for content of the said cationic polymerization initiator, with respect to 100 weight part of said cationically polymerizable compounds, a preferable minimum is 0.05 weight part, and a preferable upper limit is 10 weight part. When content of the said cationic polymerization initiator is this range, the sealing agent for organic electroluminescent display elements obtained becomes a thing more excellent in sclerosis|hardenability, storage stability, and the moisture resistance of hardened|cured material. A more preferable minimum of content of the said cationic polymerization initiator is 0.1 weight part, and a more preferable upper limit is 5 weight part.

The sealing agent for organic electroluminescent display elements of this invention may contain a thermosetting agent.

Examples of the thermal curing agent include hydrazide compounds, imidazole derivatives, acid anhydrides, dicyandiamide, guanidine derivatives, modified aliphatic polyamines, and addition products of various amines and epoxy resins.

Examples of the hydrazide compound include 1,3-bis(hydrazinocarbonoethyl)-5-isopropylhydantoin, sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid di hydrazide, malonic acid dihydrazide, etc. are mentioned.

Examples of the imidazole derivative include 1-cyanoethyl-2-phenylimidazole, N-(2-(2-methyl-1-imidazolyl)ethyl)urea, 2,4-diamino -6-(2'-Methylimidazolyl-(1'))-ethyl-s-triazine, N,N'-bis(2-methyl-1-imidazolylethyl)urea, N,N'- (2-methyl-1-imidazolylethyl)-adipoamide, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, etc. can be heard

As said acid anhydride, tetrahydro phthalic anhydride, ethylene glycol bis (anhydro trimellitate), etc. are mentioned, for example.

These thermosetting agents may be used independently and may be used in combination of 2 or more type.

As what is marketed among the said thermosetting agents, the thermosetting agent by the Otsuka Chemical company, the thermosetting agent by the Ajinomoto Fine Techno company, etc. are mentioned, for example.

SDH, ADH, etc. are mentioned as said Otsuka Chemical Co., Ltd. product thermosetting agent, for example.

As said thermosetting agent by the said Ajinomoto Fine Techno company, Amicure VDH, Amicure VDH-J, Amicure UDH, etc. are mentioned, for example.

As for content of the said thermosetting agent, with respect to 100 weight part of said cationically polymerizable compounds, a preferable minimum is 0.5 weight part, and a preferable upper limit is 30 weight part. When content of the said thermosetting agent is 0.5 weight part or more, the sealing agent for organic electroluminescent display elements obtained becomes the thing excellent in thermosetting property. When content of the said thermosetting agent is 30 weight part or less, the sealing agent for organic electroluminescent display elements obtained becomes the thing more excellent in storage stability, and hardened|cured material becomes the thing more excellent in moisture resistance. A more preferable lower limit of content of the said thermosetting agent is 1 weight part, and a more preferable upper limit is 15 weight part.

It is preferable that the sealing agent for organic electroluminescent display elements of this invention contains a stabilizer. By containing the said stabilizer, the sealing agent for organic electroluminescent display elements of this invention becomes the thing excellent in storage stability more.

As the stabilizer, an aromatic amine compound is preferably used.

As said aromatic amine compound, benzylamine, an aminophenol type epoxy resin, etc. are mentioned, for example.

Triglycidyl-p-aminophenol etc. are mentioned as said aminophenol type epoxy resin.

Especially, benzylamine is preferable.

These stabilizers may be used independently and may be used in combination of 2 or more type.

As for content of the said stabilizer, with respect to 100 weight part of said cationically polymerizable compounds, a preferable minimum is 0.001 weight part, and a preferable upper limit is 2 weight part. When content of the said stabilizer is this range, storage stability becomes more excellent, maintaining sclerosis|hardenability excellent in the sealing agent for organic electroluminescent display elements obtained. A more preferable lower limit of the content of the stabilizer is 0.005 parts by weight, and a more preferable upper limit thereof is 1 part by weight.

The sealing agent for organic electroluminescent display elements of this invention may contain a silane coupling agent. The said silane coupling agent has the role of improving adhesiveness, such as the sealing agent for organic electroluminescent display elements of this invention, and a board|substrate.

Examples of the silane coupling agent include 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-isocyanatepropyltrimethoxysilane, and the like. can be heard These silane coupling agents may be used independently and may be used in combination of 2 or more type.

As for content of the said silane coupling agent, with respect to 100 weight part of said cationically polymerizable compounds, a preferable minimum is 0.1 weight part, and a preferable upper limit is 10 weight part. When content of the said silane coupling agent is this range, suppressing that an excess silane coupling agent bleeds out, the effect of improving adhesiveness becomes more excellent. A more preferable lower limit of content of the said silane coupling agent is 0.5 weight part, and a more preferable upper limit is 5 weight part.

Moreover, from a viewpoint of low outgassing property, as for content of the said silane coupling agent, with respect to 100 weight part of said cationically polymerizable compounds, a preferable upper limit is 0.5 weight part, a more preferable upper limit is 0.1 weight part, a more preferable upper limit is 0.01 part by weight.

The sealing agent for organic electroluminescent display elements of this invention is the range which does not impair the objective of this invention further. WHEREIN: You may contain a surface modifier. By containing the said surface modifier, the flatness of the coating film of the sealing agent for organic electroluminescent display elements of this invention can be improved.

As said surface modifier, surfactant, a leveling agent, etc. are mentioned, for example.

As said surface modifier, things, such as a silicone type, an acryl type, a fluorine type, are mentioned, for example.

As what is marketed among the said surface modifiers, the surface modifier by the Big Chemical Japan company, the surface modifier by the AGC Semi-Chemical company, etc. are mentioned, for example.

As said surface modifier by the said Big Chemie Japan company, BYK-330, BYK-340, BYK-345 etc. are mentioned, for example.

As a surface modifier by the said AGC Semi-Chemical company, Suflon S-611 etc. are mentioned, for example.

The sealing agent for organic electroluminescent display elements of this invention is the range which does not impair the objective of this invention, in order to improve the durability of an element electrode, the compound or ion exchange resin which reacts with the acid which generate|occur|produced in the sealing agent for organic electroluminescent display elements may contain.

Examples of the compound reacting with the generated acid include a substance neutralizing acid and, for example, a carbonate or hydrogen carbonate of an alkali metal, or a carbonate or hydrogen carbonate of an alkaline earth metal. Specifically, for example, calcium carbonate, calcium hydrogen carbonate, sodium carbonate, sodium hydrogen carbonate and the like are used.

As said ion exchange resin, although any of a cation exchange type, an anion exchange type, and both ion exchange type can be used, In particular, the cation exchange type or both ion exchange type which can adsorb|suck chloride ion is preferable.

Although the sealing agent for organic EL display elements of the present invention may contain a solvent for the purpose of viscosity adjustment, etc., there is a possibility that problems such as deterioration of the organic light emitting material layer or the generation of outgas due to the remaining solvent Therefore, it is preferable that a solvent is not contained or content of a solvent is 0.05 weight% or less.

Moreover, the sealing agent for organic electroluminescent display elements of this invention may contain well-known various additives, such as a hardening retarder, a reinforcing agent, a softening agent, a plasticizer, a viscosity modifier, a ultraviolet absorber, and antioxidant, as needed.

The preferable upper limit of the viscosity measured on 25 degreeC and 2.5 rpm conditions using the E-type viscometer and the sealing agent for organic electroluminescent display elements of this invention is 2000 mPa*s. When the said viscosity is 2000 mPa*s or less, the sealing agent for organic electroluminescent display elements obtained becomes the thing excellent in applicability|paintability. A more preferable upper limit of the viscosity is 1500 mPa·s, and a more preferable upper limit is 1000 mPa·s.

Moreover, the preferable lower limit of the said viscosity is 10 mPa*s.

The said viscosity can be measured with the cone plate of CP1, for example using VISCOMETER TV-22 (made by Toki Industries, Ltd.) as an E-type viscometer.

As for the sealing agent for organic electroluminescent display elements of this invention, the preferable minimum of the refractive index of sodium D line|wire in 25 degreeC of hardened|cured material is 1.55. When the said refractive index is this range, the refractive index difference with an electrode and a passivation film becomes a small thing, As a result, the organic electroluminescent display element obtained becomes the thing excellent in light extraction efficiency. A more preferable lower limit of the refractive index is 1.56.

The said "refractive index of sodium D line|wire" can be measured using an Abbe-type refractometer.

In addition, as a hardened|cured material for which the said refractive index is measured, the measurement piece about 20 mm in length, 10 mm in width, and thickness 0.5-1 mm is used, for example. The cured product for measuring the refractive index can be obtained by heating at 100° C. for 30 minutes if it is a thermosetting encapsulant, and if it is a photothermal encapsulant, after irradiating an ultraviolet ray of about 2000 mJ/cm 2 , then heating at 100° C. for 30 minutes can be obtained by

The sealing agent for organic electroluminescent display elements of this invention is used especially suitably as an in-plane sealing agent which coat|covers and seals the laminated body which has an organic light emitting material layer.

Moreover, the sealing agent for organic electroluminescent display elements of this invention is used suitably for sealing of the organic electroluminescent display element of a top emission type.

As a method of sealing an organic electroluminescent display element using the sealing agent for organic electroluminescent display elements of this invention, for example, by printing, a dispensing method, or an inkjet method on the surface of an organic electroluminescent display element substrate, the present invention The method of having the process of apply|coating the sealing agent for organic electroluminescent display elements to a base material, and the process of hardening the apply|coated sealing agent for organic electroluminescent display elements by heating and/or light irradiation, etc. are mentioned.

The process of apply|coating the sealing agent for organic electroluminescent display elements of this invention to a base material WHEREIN: The sealing agent for organic electroluminescent display elements of this invention may apply|coat to the whole surface of a base material, and may apply|coat to a part of a base material. The shape of the sealing part of the sealing agent for organic electroluminescent display elements of this invention formed by application|coating will not be specifically limited if it is a shape which can protect the laminated body which has an organic light emitting material layer from external air, The laminated body completely A cover shape may be sufficient, a closed pattern may be formed in the periphery of the laminated body, and the pattern of the shape in which the opening part was formed in the periphery of the laminated body may be formed.

When the sealing agent for an organic EL display element is cured by heating, it is preferable to heat at 50° C. or more and 120° C. or less from the viewpoint of sufficiently curing while reducing damage to a laminate having an organic light-emitting material layer.

When the sealing agent for organic electroluminescent display elements of this invention is hardened by light irradiation, the sealing agent for organic electroluminescent display elements of this invention is 300 nm or more and 400 nm or less wavelength and 300 mJ/cm<2> or more and 3000 mJ/cm<2> or less It can be preferably cured by irradiating light with an accumulated light amount of

Examples of the light source used for the light irradiation include a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultra high pressure mercury lamp, an excimer laser, a chemical lamp, a black light lamp, a microwave excited mercury lamp, a metal halide lamp, a sodium lamp, a halogen lamp. , a xenon lamp, an LED lamp, a fluorescent lamp, sunlight, an electron beam irradiation device, and the like. These light sources may be used independently and 2 or more types may be used together.

These light sources are suitably selected according to the absorption wavelength of the said photocationic polymerization initiator.

As a means of irradiating light to the sealing agent for organic EL display elements of the present invention, for example, simultaneous irradiation of various light sources, sequential irradiation with a time difference, combined irradiation of simultaneous irradiation and sequential irradiation, etc. are mentioned, which irradiation means may be used.

The hardened|cured material obtained by the process of hardening the said sealing agent for organic electroluminescent display elements by heating and/or light irradiation may be coat|covered with the inorganic material film further.

As an inorganic material which comprises the said inorganic material film, a conventionally well-known thing can be used, For example, silicon nitride ( _SiNx ), silicon oxide (SiOx ₎ , etc. are mentioned. One layer may be sufficient as the said inorganic material film|membrane, and what laminated|stacked multiple types of layers may be sufficient as it. Moreover, you may coat|cover the said laminated body by repeating alternately the resin film comprised by the said inorganic material film and the sealing agent for organic electroluminescent display elements of this invention.

The method of manufacturing the said organic electroluminescent display element may have the process of bonding together the base material (henceforth "one base material") which apply|coated the sealing agent for organic electroluminescent display elements of this invention, and the other base material.

The base material to which the sealing agent for organic electroluminescent display elements of this invention is apply|coated (henceforth "one base material") may be a base material in which the laminated body which has an organic light emitting material layer is formed, The base material in which the laminated body is not formed. may be

When the said one base material is a base material in which the said laminated body is not formed, when the said other base material is bonded together, the sealing agent for organic electroluminescent display elements of this invention to the said one base material so that the said laminated body can be protected from external air. should be applied. That is, when the other base material is pasted together, it is applied entirely to the position of the laminate, or when the other substrate is bonded, the position of the laminate is completely accommodated in the shape of a closed pattern. You may form a sealing agent part.

Moreover, as a method of sealing the said organic electroluminescent display element, you may use what is called the method of dam-fill sealing. That is, first, a curable paste is applied on the substrate of the organic EL display element so as to surround the peripheral edge of the display unit. Next, the sealing agent for organic electroluminescent display elements of this invention is apply|coated to the inside of the apply|coated curable paste, and the sealing board|substrate which opposes is bonded together, preventing the protrusion of a sealing agent with the curable paste of a periphery. Then, you may use the method of hardening by heating and/or light irradiation of the curable paste of a periphery and the sealing agent for organic electroluminescent display elements of this invention which was pressed inward and spread|diffused.

The process of hardening the said sealing agent for organic electroluminescent display elements by heating and/or light irradiation may be performed before the process of bonding the said one base material and the said other base material, The said one base material and the said other base material You may carry out after the process of bonding together.

When performing the process of hardening the said sealing agent for organic electroluminescent display elements by heating and/or light irradiation before the process of bonding the said one base material and the said other base material, sealing agent for organic electroluminescent display elements of this invention It is preferable that the pot life after heating and/or light irradiation until the curing reaction proceeds and adhesion becomes impossible is 1 minute or more. When the said pot life is 1 minute or more, before bonding the said one base material and the said other base material together, hardening does not advance too much, but higher adhesive strength can be obtained.

The process of bonding the said one base material and the said other base material WHEREIN: Although the method of bonding together the said one base material and the said other base material is not specifically limited, Bonding in pressure-reduced atmosphere is preferable.

A preferable lower limit of the degree of vacuum in the reduced pressure atmosphere is 0.01 kPa, and a preferable upper limit thereof is 10 kPa. When the degree of vacuum in the reduced pressure atmosphere is within this range, it does not take a long time to achieve a vacuum state from the airtightness of a vacuum apparatus or the ability of a vacuum pump, but this invention at the time of bonding the said one base material and the said other base material together Bubbles in the sealing agent for organic electroluminescent display elements of can be removed more efficiently.

ADVANTAGE OF THE INVENTION According to this invention, it is excellent in low outgassing property and applicability|paintability, and the sealing agent for organic electroluminescent display elements from which the organic electroluminescent display element excellent in light extraction efficiency can be obtained can be provided.

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

(Examples 1 to 8, Comparative Examples 1 to 4)

According to the compounding ratio of Tables 1 and 2, each material is stirred and mixed at a stirring speed of 2000 rpm using a stirring mixer, whereby Examples 1 to 8 and Comparative Examples 1 to 4 each of the sealing agents for organic EL display elements are produced. did As the stirring mixer, AR-250 (manufactured by Thinky Co., Ltd.) was used.

<Evaluation>

The following evaluation was performed about each sealing agent for organic electroluminescent display elements obtained by the Example and the comparative example. The results are shown in Tables 1 and 2.

(1) Viscosity

About each sealing agent for organic electroluminescent display elements obtained by the Example and the comparative example, the viscosity in 25 degreeC and 2.5 rpm conditions was measured using the E-type viscometer. As the E-type viscometer, VISCOMETER TV-22 (manufactured by Toki Industries, Ltd.) was used.

(2) applicability

With respect to 100 parts by weight of each of the sealing agents for organic EL display elements obtained in Examples and Comparative Examples, 0.3 parts by weight of polymer beads having an average particle diameter of 10 µm were added, and uniformly dispersed with a planetary stirring device. As the polymer bead, micro pearl SP (manufactured by Sekisui Chemical Industry Co., Ltd.) was used. Two glass substrates of 5 cm in length and 5 cm in width were prepared, 0.1 ml of the obtained dispersion liquid was put on the center part of one glass substrate, and the diameter which spread 30 second later was measured.

When the diameter is 5.5 mm or more, "◎", 5.0 mm or more and less than 5.5 mm "○", 4.5 mm or more and less than 5.0 mm "△", and less than 4.5 mm as "x", evaluated.

(3) hardenability

About each sealing agent for organic electroluminescent display elements obtained by the Example and the comparative example, the reaction rate at the time of hardening was calculated|required.

About the sealing agent for organic electroluminescent display elements obtained in Examples 1-4, 6, 8, and Comparative Examples 1-4, the reaction calorimetry using differential scanning calorimetry (the Hitachi High-Tech Sciences company make, "DSC6220") is performed and the reaction rate was calculated using the following formula (I). In formula (I), H ₀ is the amount of reaction heat when the temperature is raised to 40°C to 200°C at a temperature increase rate of 10°C/min in an uncured state using an aluminum sample pan in a nitrogen gas atmosphere. Moreover, in calculation formula ( _I ), H1 is reaction heat amount when the sealing agent for organic electroluminescent display elements heat-hardened at 100 degreeC for 30 minutes is heated up to 40 degreeC - 200 degreeC at a temperature increase rate of 10 degreeC/min. .

(H ₀ - H ₁ )/H ₀ (I)

Moreover, about the sealing agent for organic electroluminescent display elements obtained in Examples 5 and 7, using Photo-DSC (the TA Instruments company make, "DSC Q100" and light source device "Qseries PCA" combination), active energy ray Reaction calorimetry was measured at the time of irradiation and at the time of temperature rise, and the reaction rate was computed using the following formula (II). In formula (II), H ₂ is a high-pressure mercury lamp (without cut-off filter) in a nitrogen atmosphere at 25°C, irradiating an active energy ray with an illuminance of 3.7 W/cm 2 and an accumulated light quantity of 1.5 J/cm 2 , immediately after irradiation , It is the total calorific value from before active energy ray irradiation to completion|finish of temperature increase when it heats up to 40 degreeC - 200 degreeC at a temperature increase rate of 10 degreeC/min. The said integrated light quantity measures the integrated light quantity with a wavelength of 351 nm using UV-351 (made by ORC). In the formula (II), H ₃ is immediately after irradiation with active energy rays under the above conditions, the temperature is raised to 100° C. at a temperature increase rate of 20° C./min., and after holding at 100° C. for 30 minutes, at 10° C./min. It is the calorific value (H ₃ ) from cooling to 25° C. to completion of temperature increase at 200° C. when it is cooled to 25° C. and then heated to 200° C. at a temperature increase rate of 10° C./min.

(H ₂ − H ₃ )/H ₂ (II)

When the reaction rate is 90% or more, "◎", 80% or more and less than 90% "○", 60% or more and less than 80% "Δ", and less than 60% was evaluated as "x".

(4) refractive index and light extraction efficiency

A silicone rubber sheet having a thickness of 1 mm was cut out into a rectangle having a length of 20 mm and a width of 10 mm to prepare a mold. This mold was placed on a mold release PET film, and the sealing agent for organic EL display elements obtained in Examples and Comparative Examples was filled in the mold, and then covered with another mold release PET film so as not to leave bubbles to obtain a laminate. The obtained laminated body was pinched|interposed between the glass plates of 2 sheets, and was fixed, and the sealing agent was hardened. About the sealing agent for organic electroluminescent display elements obtained in Examples 1-4, 6, 8, and Comparative Examples 1-4, it heats at 100 degreeC for 30 minutes, and hardens, For organic electroluminescent display elements obtained in Examples 5 and 7 About the sealing agent, after irradiating 1500 mJ/cm<2> of ultraviolet-rays with a wavelength of 365 nm using UV-LED, it heated and hardened at 90 degreeC for 30 minute(s). Then, the PET film was peeled off, the hardened|cured material of the sealing agent was taken out from the silicone rubber sheet, and the test piece of length 10mm, width 20mm, and thickness 1mm was obtained. About the obtained test piece, the refractive index of the sodium D line|wire in 25 degreeC was measured using the Abbe-type refractometer. As the Abbe type refractometer, NAR-4T (manufactured by Atago Corporation) was used.

In addition, in consideration of the refractive index difference between the electrode and the passivation film, the case where the refractive index is 1.56 or more is "○", the case where it is 1.54 or more and less than 1.56 is "Δ", and the case where it is less than 1.54 is "x", and the light extraction efficiency was evaluated.

(5) low outgassing properties

After measuring 300 mg and sealing each sealing agent for organic electroluminescent display elements obtained by the Example and the comparative example in a vial bottle, it was hardened. About the sealing agent for organic electroluminescent display elements obtained in Examples 1-4, 6, 8, and Comparative Examples 1-4, it heats at 100 degreeC for 30 minutes, and hardens, For organic electroluminescent display elements obtained in Examples 5 and 7 About the sealing agent, after irradiating 1500 mJ/cm<2> of ultraviolet-rays with a wavelength of 365 nm using UV-LED, it heated and hardened at 90 degreeC for 30 minute(s). Moreover, this vial bottle was heated in 85 degreeC constant temperature oven for 100 hours, and the vaporized component amount in a vial bottle was measured using the gas chromatograph mass spectrometer. As a gas chromatograph mass spectrometer, JMS-Q1050 (made by Nippon Electronics Co., Ltd.) was used.

Low outgas properties were evaluated as "○" when the amount of vaporized components was less than 50 ppm, "Δ" when 50 ppm or more and less than 100 ppm, and "x" when it was 100 ppm or more.

Industrial Applicability

ADVANTAGE OF THE INVENTION According to this invention, it is excellent in low outgassing property and applicability|paintability, and the sealing agent for organic electroluminescent display elements from which the organic electroluminescent display element excellent in light extraction efficiency can be obtained can be provided.

Claims (7)

As a sealing agent for organic EL display elements containing a cation polymerizable compound and a cation polymerization initiator,
The said cation polymeric compound contains the compound which has a cycloalkenoxide type alicyclic epoxy compound, and a biphenyl skeleton and an epoxy group or oxetanyl group, The sealing agent for organic electroluminescent display elements characterized by the above-mentioned. The method of claim 1,
Content of the said cycloalkenoxide type alicyclic epoxy compound in 100 weight part of said cation polymeric compounds is 3 weight part or more and 45 weight part or less, Content of the compound which has the said biphenyl skeleton and an epoxy group or oxetanyl group This 30 parts by weight or more and 97 parts by weight or less of the sealing agent for organic EL display elements. 3. The method of claim 1 or 2,
The said cation polymeric compound adds to the compound which has the said cycloalkenoxide type alicyclic epoxy compound and the said biphenyl skeleton and an epoxy group or an oxetanyl group, and contains other cationically polymerizable compound Encapsulation for organic electroluminescent display elements My. 4. The method of claim 3,
As the other cationically polymerizable compound, 3-ethyl-3-(((3-ethyloxetan-3-yl)methoxy)methyl)oxetane, 1,2:7,8-diepoxyoctane, and , 1,2:5,6-diepoxycyclooctane at least one type selected from the group consisting of a sealing agent for an organic EL display element. 5. The method of claim 4,
The sealing agent for organic electroluminescent display elements containing 3-ethyl-3-(((3-ethyloxetan-3-yl)methoxy)methyl)oxetane as said other cationically polymerizable compound. 6. The method according to claim 3, 4 or 5,
The sealing agent for organic electroluminescent display elements whose content of the said other cationically polymerizable compound in 100 weight part of said cationically polymerizable compounds is 10 weight part or more and 50 weight part or less. 7. The method of claim 1, 2, 3, 4, 5 or 6,
The said cationic polymerization initiator, the encapsulant for organic electroluminescent display elements containing the quaternary ammonium salt whose counter anion is a borate type.