JP6427282B2 - Sealant for organic EL display elements - Google Patents

Description

The present invention relates to 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 is excellent in reliability.

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 electrodes facing each other, and from this one electrode to the organic light emitting material layer The injection of electrons and the injection of holes from the other electrode combine the electrons and the holes in the organic light emitting material layer to emit light. As described above, since the organic EL display element emits light by itself, it has better visibility than a liquid crystal display element requiring a backlight, can be thinned, and can be driven by a low DC voltage. It has the advantage of

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

In the method of sealing with a silicon nitride film disclosed in Patent Document 1, organic light emission occurs when forming a silicon nitride film due to unevenness of the surface of an organic EL display element, adhesion of foreign matter, generation of cracks due to internal stress, etc. It may not be possible to completely cover the material layer or the electrode. If the coating by the silicon nitride film is incomplete, moisture may permeate into the organic light emitting material layer through the silicon nitride film.
Patent Document 2 discloses a method of alternately depositing an inorganic material film and a resin film as a method for preventing the entry of moisture into the organic light emitting material layer, and Patent Document 3 and Patent Document 4 Discloses a method of forming a resin film on an inorganic material film.

As a method of forming a resin film, there is a method of applying a sealing agent on a substrate using an inkjet method and then curing the sealing agent. By using a coating method using such an inkjet method, a resin film can be formed at high speed and uniformly. However, when the sealing agent is made to have a low viscosity in order to make it suitable for application by the ink jet method, outgassing occurs or cracks occur in the inorganic material film, resulting in insufficient sealing. There were problems such as the organic EL display element becoming less reliable.

JP 2000-223264 A Japanese Patent Application Publication No. 2005-522891 JP, 2001-307873, A JP, 2008-149710, A

An object of the present invention is 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 is excellent in reliability. I assume.

Invention 1 contains a polymerizable compound and a polymerization initiator, has a viscosity of 5 to 50 mPa · s at 25 ° C., a surface tension of 15 to 35 mN / m at 25 ° C., 40 to 50 ° C. linear expansion coefficient of 50~140ppm / ℃ der cured product in the temperature range of is, containing no solvent, or the content of the solvent is a sealant for an organic EL display element is 0.05 wt% or less .
The present invention 2 is a sealant for an organic EL display element used for coating by an inkjet method, which contains a polymerizable compound and a polymerization initiator, and a line of a cured product in a temperature range of 40 ° C. to 50 ° C. expansion coefficient Ri 50~140ppm / ℃ der, containing no solvent, or, the content of the solvent is an organic EL display element sealing agent is 0.05 wt% or less.
The present invention will be described in detail below. In addition, about the matter common to the sealing agent for organic EL display elements of this invention 1, and the sealing agent for organic EL display elements of this invention 2, it describes as "the sealing agent for organic EL display elements of this invention" Do.

The inventors of the present invention have made the linear expansion coefficient of the cured product in the temperature range from 40 ° C. to 50 ° C. to be in a specific range for the sealing agent for an organic EL display element having excellent ink jet coatability. investigated. As a result, it has been found that it is possible to obtain a sealing agent for an organic EL display element which can be easily applied by the inkjet method, which is excellent in low outgassing property, and which is excellent in reliability. The present invention has been completed.

The sealing agent for an organic EL display element of the present invention can also be used for application by a non-heating inkjet method as an inkjet method, and can also be used for application by a heating inkjet method.
In the present specification, the above-mentioned "non-heating type inkjet method" is a method of inkjet coating at a coating head temperature of less than 28 ° C, and the above "heating type inkjet method" is an inkjet method at a coating head temperature of 28 ° C or more It is a method of applying.

An inkjet application head equipped with a heating mechanism is used for the above-mentioned heating type inkjet method. By mounting the heating mechanism on the inkjet coating head, it is possible to reduce the viscosity and the surface tension when discharging the sealing agent for an organic EL display element.

As a coating head for inkjets which carries the above-mentioned heating mechanism, KM1024 series made from Konica Minolta, SG1024 series made from Fujifilm Dimatix, etc. are mentioned, for example.

When using the sealing agent for organic EL display elements of this invention for application | coating by the said heating type inkjet method, it is preferable that the heating temperature of a coating head is the range of 28 degreeC-80 degreeC. When the heating temperature of the application head is in this range, the increase in viscosity with time of the sealing agent for an organic EL display element is suppressed, and the discharge stability becomes excellent.

The sealing agent for an organic EL display element of the first invention has a viscosity lower limit of 5 mPa · s and an upper limit of 50 mPa · s. When the said viscosity is this range, it can apply suitably by the inkjet method.
In the present specification, the above viscosity means a value measured under conditions of 25 ° C. and 100 rpm using an E-type viscometer.

The preferable lower limit of the viscosity of the sealant for an organic EL display element of the present invention in the case of coating by the non-heating inkjet method is 5 mPa · s, and the preferable upper limit is 20 mPa.s. s. When the said viscosity is this range, it can apply suitably by the non-heating-type inkjet method. A more preferable lower limit of the viscosity of the sealant for an organic EL display element of the present invention in the case of coating by the non-heating inkjet method is 8 mPa · s, and a more preferable upper limit is 16 mPa.s. s, a more preferable lower limit is 10 mPa · s, and a still more preferable upper limit is 13 mPa.s. s.

On the other hand, the preferable lower limit of the viscosity of the sealant for an organic EL display element of the present invention when used for coating by the heating inkjet method is 10 mPa · s, and the preferable upper limit is 50 mPa.s. s. Since the said viscosity is this range, it can apply suitably by a heating type inkjet method. A more preferable lower limit of the viscosity of the sealant for an organic EL display element of the present invention when used for coating by the heating inkjet method is 20 mPa · s, and a more preferable upper limit is 40 mPa.s. s.

The sealing agent for an organic EL display element of the first invention has a lower limit of surface tension of 15 mN / m and an upper limit of 35 mN / m. When the surface tension is in this range, it can be suitably applied by the inkjet method. The lower limit of the surface tension is preferably 20 mN / m, preferably 30 mN / m, more preferably 22 mN / m, and more preferably 28 mN / m.
Moreover, as for the sealing agent for organic EL display elements of this invention 2, the preferable minimum of surface tension is 15 mN / m, and a preferable upper limit is 35 mN / m. When the surface tension is in this range, it can be suitably applied by the 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.
In addition, the said surface tension means the value measured by the Wilhelmy method by a dynamic wettability tester at 25 degreeC.

The lower limit of the linear expansion coefficient of the cured product in the temperature range from 40 ° C. to 50 ° C. is 50 ppm / ° C., and the upper limit is 140 ppm / ° C. When the linear expansion coefficient is in this range, the occurrence of cracks in the inorganic material film can be suppressed, and the obtained organic EL display element becomes excellent in reliability. The lower limit of the linear expansion coefficient is preferably 60 ppm / ° C., preferably 130 ppm / ° C., more preferably 70 ppm / ° C., and still more preferably 120 ppm / ° C.
In the present specification, the above-mentioned “linear expansion coefficient” indicates a value measured by the TMA method under the conditions of a temperature rising rate of 5 ° C./min and a force of 0.1 N.
Moreover, if it is a photocurable sealing agent, the hardened | cured material used for the measurement of the said linear expansion coefficient is obtained by irradiating 3000 mJ / cm < ² > of ultraviolet rays with a wavelength of 365 nm by LED lamp to a sealing agent, for example. If it is a thermosetting sealant, it can be obtained, for example, by heating at 80 ° C. for 1 hour.

The viscosity, the surface tension, and the linear expansion coefficient may be adjusted by selecting these types and adjusting the content ratio of the polymerizable compound, the polymerization initiator, and other components that may be contained, which will be described later. It can be in the range described above.
In particular, the above linear expansion coefficient can be made into the above-mentioned range by a method of using a rigid component having high heat resistance as a polymerizable compound described later, using a filler, or the like.

Examples of the rigid component having high heat resistance include a polymerizable compound in which an alicyclic skeleton having a reactive functional group is introduced, a polymerizable compound in which a heterocyclic skeleton having a reactive functional group is introduced, and a reactive functional group. Examples thereof include polymerizable compounds into which an aromatic skeleton having a group is introduced.

As the filler, an inorganic compound having a small linear thermal expansion coefficient is suitably used.
Specific examples of the filler include silica, alumina, magnesia, zirconia and the like.
Moreover, since high transparency may be required for the hardened | cured material of the sealing agent for organic EL display elements, it is preferable that the said filler is a nano filler of a nanosized particle diameter.
Furthermore, as the above-mentioned filler, in order to improve the dispersibility with the curable resin, it is preferable to have a surface treatment.

The sealing agent for an organic EL display element of the present invention contains a polymerizable compound.
A cationically polymerizable compound or a radically polymerizable compound can be used as the above-mentioned polymerizable compound. Among them, cationically polymerizable compounds are preferable.

As said cationically polymerizable compound, an epoxy compound, an oxetane compound, a vinyl ether compound etc. are mentioned, for example. Among them, epoxy compounds or oxetane compounds are preferable.

Examples of the epoxy compound include bisphenol A epoxy resin, bisphenol E epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, bisphenol O epoxy resin, 2,2′-diallyl bisphenol A epoxy resin, Alicyclic epoxy resin, hydrogenated bisphenol epoxy resin, propylene oxide added bisphenol A epoxy resin, resorcinol epoxy resin, biphenyl epoxy resin, sulfide epoxy resin, diphenyl ether epoxy resin, dicyclopentadiene epoxy resin, naphthalene Epoxy resin, phenol novolac epoxy resin, ortho cresol novolac epoxy resin, dicyclopentadiene novolac epoxy resin, biphenylno There may be mentioned, for example, a volac epoxy resin, a naphthalene phenol novolac epoxy resin, a glycidyl amine epoxy resin, an alkyl polyol epoxy resin, a rubber-modified epoxy resin, and a glycidyl ester compound. Among them, alicyclic epoxy resins are preferable.
Among the above-mentioned alicyclic epoxy resins, commercially available ones are, for example, Celoxide 2000, Celoxide 2021 P, Celoxide 2081, Celoxide 3000, Celoxide 8000 (all manufactured by Daicel), Sanssoizer EPS (manufactured by Shin Nippon Rika Kogyo Co., Ltd.) Etc.).

Examples of the above oxetane compounds include allyloxy oxetane, phenoxymethyl oxetane, 3-ethyl-3-hydroxymethyl oxetane, 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, Oxetanyl silsesquioxane, phenol novolac oxetane, 1,4-bis (((3-ethyl-3-oxetanyl) methoxy) methyl) benzene and the like can be mentioned.

Examples of the vinyl ether compounds include benzyl vinyl ether, cyclohexane dimethanol monovinyl ether, dicyclopentadiene vinyl ether, 1,4-butanediol divinyl ether, cyclohexane dimethanol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, dipropylene glycol Divinyl ether, tripropylene glycol divinyl ether and the like can be mentioned.

As said radically polymerizable compound, a (meth) acrylic compound is preferable.
The (meth) acrylic compound may be a monofunctional (meth) acrylic compound or a polyfunctional (meth) acrylic compound, and the monofunctional (meth) acrylic compound and the polyfunctional (meth) compound You may use it in combination with an acrylic compound.
In the present specification, the above "(meth) acrylic" means acrylic or methacrylic, and the above "(meth) acrylic compound" means a compound having a (meth) acryloyl group, and the above "(meth) acrylic acid" Acryloyl "means acryloyl or methacryloyl.

The monofunctional (meth) acrylic compound preferably has a cationically polymerizable group from the viewpoint of low outgassing and the like.
As said cationically polymerizable group, a vinyl ether group, an epoxy group, oxetanyl group, allylether group, a vinyl group, a hydroxyl group etc. are mentioned, for example.

Specific examples of the monofunctional (meth) acrylic compound include 3,4-epoxycyclohexylmethyl (meth) acrylate, glycidyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, and (meth) acrylic. Acid 2- (2-vinyloxyethoxy) ethyl, 3-ethyl-3- (meth) acryloxymethyl oxetane, allyl (meth) acrylate, methoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, ethoxydiethylene glycol Examples include (meth) acrylate, ethoxytriethylene glycol (meth) acrylate, 2- (2-vinyloxyethoxy) ethyl (meth) acrylate and the like. Among them, 3,4-epoxycyclohexylmethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, and 2- (2-vinyloxyethoxy) ethyl (meth) acrylate are preferable.
In the present specification, the above "(meth) acrylate" means acrylate or methacrylate.

When the polymerizable compound contains the monofunctional (meth) acrylic compound, the preferable 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 preferable upper limit is 80 It is a weight part. When the content of the monofunctional (meth) acrylic compound is in this range, the obtained sealant for an organic EL display element is excellent due to the low outgassing property and the like. The more preferable lower limit of the content of the monofunctional (meth) acrylic compound is 30 parts by weight, and the more preferable upper limit is 60 parts by weight.

The polyfunctional (meth) acrylic compound preferably has a polyoxyalkylene skeleton in the main chain from the viewpoint of inkjet coatability and the like.
It is preferable that the said polyoxyalkylene frame | skeleton is a thing in which 2-6 six oxyalkylene units continue.
As an oxyalkylene unit which comprises the said polyoxyalkylene frame | skeleton, an oxyethylene unit, an oxypropylene unit, etc. are mentioned.

From the viewpoint of inkjet coatability and the like, the polyfunctional (meth) acrylic compound preferably has a structure in which carbon chain branching is small, and more preferably linear.

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. And tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, polytetramethylene glycol di (meth) acrylate and the like. Among them, tetraethylene glycol di (meth) acrylate is preferable.

When the polymerizable compound contains the polyfunctional (meth) acrylic compound, the preferable 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 preferable upper limit is 80 It is a weight part. When the content of the polyfunctional (meth) acrylic compound is in this range, the obtained sealant for an organic EL display element is excellent in ink jet coatability and the like. A more preferable lower limit of 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 a weight ratio Monofunctional (meth) acrylic compound: Multifunctional (meth) acrylic compound = 7: 3 to 3: 7 is preferable. By making the content ratio of the monofunctional (meth) acrylic compound and the polyfunctional (meth) acrylic compound into this range, the obtained sealant for an organic EL display element is excellent in ink jet coatability and the like. be able to. The content ratio of the monofunctional (meth) acrylic compound to the polyfunctional (meth) acrylic compound is, in weight ratio, monofunctional (meth) acrylic compound: polyfunctional (meth) acrylic compound = 6: 4 to 4: 6. It is more preferable that

The sealing agent for an organic EL display element of the present invention contains a polymerization initiator.
As said polymerization initiator, according to the kind etc. of a polymeric compound to be used, a photocationic polymerization initiator, a thermal cationic polymerization initiator, a photoradical polymerization initiator, and a thermal radical polymerization initiator are used suitably. Among them, it is preferable that the polymerizable compound is an epoxy compound or an oxetane compound, and the polymerization initiator is a cationic polymerization initiator.

The photo cationic polymerization initiator is not particularly limited as long as it generates a protonic acid or a Lewis acid upon irradiation with light, and may be an ionic photoacid generating type or a nonionic photoacid generating type. May be

Examples of the anionic moiety of the above-mentioned ionic photoacid generation type cationic photopolymerization initiator include BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , or (BX ₄ ) ⁻ (wherein X is at least 2 or more). And a phenyl group substituted with a trifluoromethyl group or the like) and the like.
Examples of the above-mentioned ionic photoacid-generating photocationic polymerization initiator include an aromatic sulfonium salt, an aromatic iodonium salt, an aromatic diazonium salt, an aromatic ammonium salt, and an aromatic ammonium salt having the above-mentioned anion moiety. Pentadien-1-yl) ((1-methylethyl) benzene) -Fe salt and the like can be mentioned.

Examples of the aromatic sulfonium salt include bis (4- (diphenylsulfonio) phenyl) sulfide bishexafluorophosphate, bis (4- (diphenylsulfonio) phenyl) sulfide bishexafluoroantimonate, bis (4- (diphenyl) Diphenylsulfonio) phenyl) sulfide bis tetrafluoroborate, bis (4- (diphenylsulfonio) phenyl) sulfide tetrakis (pentafluorophenyl) borate, diphenyl-4- (phenylthio) phenylsulfonium hexafluorophosphate, diphenyl-4- (4) Phenylthio) phenylsulfonium hexafluoroantimonate, diphenyl-4- (phenylthio) phenylsulfonium tetrafluoroborate, diphenyl-4- (phenylthio) Phenylsulfonium tetrakis (pentafluorophenyl) borate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrafluoroborate, triphenylsulfonium tetrakis (pentafluorophenyl) borate, bis (4- (di ( 4- (2-hydroxyethoxy)) phenylsulfonio) 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 ( - (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 salt 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 hexame Fluorophosphate, 4-methylphenyl-4- (1-methylethyl) Henyliodonium hexafluoroantimonate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium tetrafluoroborate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium tetrakis (pentafluorophenyl) borate, etc. It can be mentioned.

Examples of the aromatic diazonium salt include phenyl diazonium hexafluorophosphate, phenyl diazonium hexafluoro antimonate, phenyl diazonium tetrafluoroborate, phenyl diazonium tetrakis (pentafluorophenyl) borate and the like.

Examples of the above-mentioned aromatic ammonium salt 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.

As the above (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-cyclopentadiene-1) -Yl) ((1-methylethyl) benzene) -Fe (II) tetrafluoroborate, (2,4-cyclopentadien-1-yl) ((1-methylethyl) benzene) -Fe (II) tetrakis (penta) And fluorophenyl) borate and the like.

Examples of the nonionic photoacid-generating photocationic polymerization initiator include nitrobenzyl ester, sulfonic acid derivative, phosphoric acid ester, phenol sulfonic acid ester, diazonaphthoquinone, N-hydroxyimidosulfonate and the like.

Among the above cationic photopolymerization initiators, commercially available ones are, for example, DTS-200 (manufactured by Midori Kagaku Co., Ltd.), UVI 6990, UVI 6974 (all manufactured by Union Carbide), SP-150, SP-170 (all of them) Adeka company make, FC-508, FC-512 (all are 3M company made), IRGACURE 261, IRGACURE 290 (all are BASF company make), PI 2074 (made by Rhodia company) etc. are mentioned.

As said thermal cationic polymerization initiator, the anionic part is substituted by BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , or (BX ₄ ) ⁻ (wherein X is at least two or more fluorine or trifluoromethyl groups) And a sulfonium salt, a phosphonium salt, an ammonium salt and the like. Among these, sulfonium salts and ammonium salts are preferable.

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

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

Examples of the ammonium salt include dimethylphenyl (4-methoxybenzyl) ammonium hexafluorophosphate, dimethylphenyl (4-methoxybenzyl) ammonium hexafluoroantimonate, and dimethylphenyl (4-methoxybenzyl) ammonium tetrakis (pentafluorophenyl). Borate, dimethylphenyl (4-methylbenzyl) ammonium hexafluorophosphate, dimethylphenyl (4-methylbenzyl) ammonium hexafluoroantimonate, dimethylphenyl (4-methylbenzyl) ammonium hexafluorotetrakis (pentafluorophenyl) borate, methylphenyl Dibenzylammonium hexafluorophosphate, methylphenyldibenzylammonium chloride Safluoroantimonate, methylphenyldibenzylammonium tetrakis (pentafluorophenyl) borate, phenyltribenzylammonium 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-benzyl pyridinium trifluoromethanesulfonic acid etc. are mentioned.

Among the above thermal cationic polymerization initiators, commercially available ones are, for example, SAN-AID SI-60, SAN-AID SI-80, SAN-AID SI-B3, SAN-AID SI-B3A, SAN-AID SI-B4 (all of which are San Shin Chemical Industry Co., Ltd.) And CXC 1612 and CXC 1821 (all manufactured by King Industries).

Examples of the photoradical polymerization initiator include benzophenone compounds, acetophenone compounds, acyl phosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, benzyl and thioxanthone compounds.

Among the above photo radical polymerization initiators, commercially available ones are IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACURE OXE01, Lucillin TPO (all manufactured by BASF), benzoin methyl ether, benzoin Ethyl ether, benzoin isopropyl ether (all are manufactured by Tokyo Chemical Industry Co., Ltd.), etc. may be mentioned.

As said thermal radical polymerization initiator, what consists of an azo compound, an organic peroxide, etc. is mentioned, for example.
Examples of the azo compound include 2,2′-azobis (2,4-dimethylvaleronitrile), azobisisobutyronitrile, and the like.
Examples of the organic peroxide include benzoyl peroxide, ketone peroxide, peroxy ketal, hydroperoxide, dialkyl peroxide, peroxy ester, diacyl peroxide, peroxy dicarbonate and the like.

Among the thermal radical polymerization initiators that are commercially available, for example, VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS-1001, V-501 (all of which are manufactured by Wako Pure Chemical Industries, Ltd. Etc.).

The content of the polymerization initiator is preferably 0.01 parts by weight with a preferable lower limit and 10 parts by weight with a preferable upper limit based on 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 an organic EL display element is more excellent in curability. When the content of the polymerization initiator is 10 parts by weight or less, the curing reaction of the obtained sealant for an organic EL display element does not become too fast, and the workability becomes excellent, and the cured product becomes more uniform It can be done. The more preferable lower limit of the content of the polymerization initiator is 0.05 parts by weight, and the more preferable upper limit is 5 parts by weight.

The sealant for an organic EL display element of the present invention may contain a sensitizer. The sensitizer has a role of further improving the polymerization initiation efficiency of the polymerization initiator to further accelerate the curing reaction of the sealing agent for an organic EL display element of the present invention.

Examples of the sensitizer include thioxanthone compounds such as 2,4-diethylthioxanthone, 2,2-dimethoxy-1,2-diphenylethane-1-one, benzophenone, 2,4-dichlorobenzophenone, o- Methyl benzoyl benzoate, 4,4'-bis (dimethylamino) benzophenone, 4-benzoyl 4'- methyl diphenyl sulfide etc. are mentioned.

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

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

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

The preferable lower limit of the content of the silane coupling agent is 0.1 parts by weight and the preferable upper limit is 10 parts by weight with respect to 100 parts by weight of the polymerizable compound. When the content of the silane coupling agent is in this range, it is possible to suppress the bleeding out of the excess silane coupling agent, and to be more excellent in the effect of improving the adhesiveness. A more preferable lower limit of 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 sealing agent for an organic EL display element of the present invention may further contain a surface modifier, as long as the object of the present invention is not hindered. By containing the said surface modifier, the flatness of a coating film can be provided to the sealing agent for organic EL display elements of this invention.
As said surface modifier, surfactant, a leveling agent, etc. are mentioned, for example.

As said surface modifier, things, such as a silicone type and a fluorine type, are mentioned, for example.
Among the above surface modifiers, commercially available ones include BYK-340, BYK-345 (all of which are manufactured by Big Chemie Japan), Surfron S-611 (manufactured by AGC Seimi Chemical Co., Ltd.), and the like.

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

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

As a method for producing the sealing agent for an organic EL display element of the present invention, for example, a polymerizable compound and a mixing machine such as a homodisper, a homomixer, a universal mixer, a planetary mixer, a kneader or a 3-roll mill are used. And a method of mixing a polymerization initiator and an additive such as a silane coupling agent which is added as necessary.

The preferable lower limit of the total light transmittance of light at a wavelength of 380 to 800 nm of the cured product of the sealant for an organic EL display element of the present invention is 80%. By the said total light beam transmittance | permeability being 80% or more, the organic EL display element obtained becomes what is excellent by an optical characteristic. A more preferable lower limit of the total light transmittance is 85%.
The total light transmittance can be measured, for example, using a spectrometer such as AUTOMATIC HAZE MATER MODEL TC = III DPK (manufactured by Tokyo Denshoku Co., Ltd.).
Moreover, if the cured | curing material used for the measurement of the said total light transmittance is a photocurable sealing agent, it will obtain by irradiating 3000 mJ / cm < ² > of ultraviolet rays with a wavelength of 365 nm to LED light for example to a sealing agent. The thermosetting sealant can be obtained, for example, by heating at 80 ° C. for one hour.

The sealant for an organic EL display element of the present invention is preferably such that the transmittance at 400 nm after irradiating the cured product with ultraviolet light for 100 hours is 85% or more at an optical path length of 20 μm. When the transmittance after irradiation with the ultraviolet light for 100 hours is 85% or more, the transparency is high, the loss of light emission becomes small, and the color reproducibility becomes excellent. The more preferable lower limit of the transmittance after irradiation with ultraviolet light for 100 hours is 90%, and the further preferable lower limit is 95%.
As a light source which irradiates the said ultraviolet-ray, conventionally well-known light sources, such as a xenon lamp and a carbon arc lamp, can be used, for example.
Moreover, if the cured product used for the measurement of the transmittance | permeability after irradiating the said ultraviolet-ray for 100 hours is a photocurable sealing agent, the ultraviolet-ray of wavelength 365nm will be 3000 mJ / cm with a LED lamp to a sealing agent, for example. ⁽² ) It can be obtained by irradiation, and if it is a thermosetting sealant, it can be obtained, for example, by heating at 80 ° C. for 1 hour.

The sealant for an organic EL display device of the present invention has a moisture permeability of 100 g / l at a thickness of 100 μm measured by exposing the cured product to an environment of 85 ° C. and 85% RH for 24 hours according to JIS Z 0208. m is preferably ² or less. When the moisture permeability is 100 g / m ² or less, the effect of preventing the occurrence of dark spots due to the arrival of moisture to the organic light emitting material layer is improved, and the obtained organic EL display element is more excellent in reliability. It becomes a thing.
Moreover, if it is a photocurable sealing agent, the hardened | cured material used for the measurement of the said moisture permeability will be obtained by irradiating 3000 mJ / cm < ² > of ultraviolet rays with a wavelength of 365 nm with an LED lamp to a sealing agent, for example. A thermosetting sealant can be obtained, for example, by heating at 80 ° C. for 1 hour.

Furthermore, in the sealant for an organic EL display element of the present invention, when the cured product is exposed to an environment of 85 ° C. and 85% RH for 24 hours, the moisture content of the cured product is less than 0.5%. preferable. When the moisture content of the cured product is less than 0.5%, the effect of preventing the deterioration of the organic light emitting material layer due to the moisture in the cured product becomes excellent, and the obtained organic EL display element is more excellent in reliability It becomes. The more preferable upper limit of the moisture content of the said hardened | cured material is 0.3%.
Examples of the method of measuring the water content include a method of obtaining by Karl Fisher method in accordance with JIS K 7251, and a method of obtaining weight increment after water absorption in accordance with JIS K 7209-2.
Moreover, if it is a photocurable sealing agent, the hardened | cured material used for the measurement of the said moisture content will be obtained by irradiating 3000 mJ / cm < ² > of ultraviolet rays with a wavelength of 365 nm with LED lamp to a sealing agent, for example. A thermosetting sealant can be obtained, for example, by heating at 80 ° C. for 1 hour.

The sealing agent for an organic EL display element of the first invention is suitably used for application by an ink jet method, and the sealing agent for an organic EL display element of the present invention 2 is used for application by an ink jet method.
As a method for producing an organic EL display element using the sealing agent for an organic EL display element of the present invention, for example, a step of applying the sealing agent for an organic EL display element of the present invention to a substrate by an inkjet method And a step of curing the applied sealing agent for an organic EL display element by light irradiation and / or heating.

In the step of applying the sealant for an organic EL display device of the present invention to a substrate, the sealant for an organic EL display device of the present invention may be applied to the entire surface of the substrate, or to a part of the substrate It may be applied. 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 can protect the laminate having the organic light emitting material layer from the open air, The shape may be a shape that completely covers the body, or a closed pattern may be formed on the periphery of the laminate, or a pattern having a shape in which openings are partially provided on the periphery of the laminate. You may form.

When the sealant for an organic EL display device of the present invention is cured by light irradiation, the sealant for an organic EL display device of the present invention has a wavelength of 300 nm to 400 nm and an integrated light amount of 300 to 3000 mJ / cm ^2. It can be suitably cured by irradiation.

As a light source for irradiating light to the sealing agent for organic EL display elements of the present invention, for example, low pressure mercury lamp, medium pressure mercury lamp, high pressure mercury lamp, super high pressure mercury lamp, excimer laser, chemical lamp, black light lamp, microwave Excitation mercury lamps, metal halide lamps, sodium lamps, halogen lamps, xenon lamps, LED lamps, fluorescent lamps, sunlight, electron beam irradiation devices and the like can be mentioned. These light sources may be used alone or in combination of two or more.
These light sources are suitably selected according to the absorption wavelength of the said radical photopolymerization initiator and cationic photopolymerization initiator.

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

The cured product obtained by the step of curing the sealing agent for an organic EL display element by light irradiation and / or heating may be further coated with an inorganic material film.
As the inorganic material constituting the inorganic material film, conventionally known materials can be used, and examples thereof include silicon nitride (SiN _x ) and silicon oxide (SiO _x ). The inorganic material film may be composed of a single layer, or may be a laminate of multiple types of layers. Further, the laminate may be coated by alternately repeating the above-mentioned inorganic material film and the resin film made of the sealing agent for an organic EL display element of the present invention.

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

The step of curing the sealing agent for an organic EL display element by light irradiation and / or heating may be performed before the step of bonding the one base and the other base, or the one side You may carry out after the process of bonding a base material and said other base material together.
When the step of curing the sealing agent for an organic EL display element by light irradiation and / or heating is performed before the step of bonding the one base and the other base, the organic EL display of the present invention The sealing agent for elements preferably has a pot life of 1 minute or more after light irradiation and / or heating until curing reaction proceeds and adhesion can not be performed. By setting the usable time to 1 minute or more, higher adhesion strength can be obtained without curing progressing too much before laminating the one base material and the other base material.

In the step of bonding the one base and the other base, the method of bonding the one base and the other base is not particularly limited, but bonding in a reduced pressure atmosphere is preferable.
The preferable lower limit of the vacuum degree in the said pressure-reduced atmosphere is 0.01 kPa, and a preferable upper limit is 10 kPa. When the degree of vacuum under the reduced pressure atmosphere is in this range, it does not take a long time to achieve a vacuum state from the airtightness of the vacuum device and the ability of the vacuum pump, and the one base and the other base Air bubbles in the sealant for an organic EL display element of the present invention at the time of pasting together materials can be removed more efficiently.

According to the present invention, it is possible to provide a sealing agent for an organic EL display element which can be easily applied by the inkjet method, can obtain an organic EL display element excellent in low outgassing property and excellent in reliability. Can.

EXAMPLES The present invention will be described in more detail by way of the following examples, but the present invention is not limited to these examples.

(Examples 1-5, comparative examples 1-4)
According to the compounding ratio described in Table 1, Example 1 was obtained by uniformly stirring and mixing each material at a stirring speed of 3000 rpm using a homodisper type stirring mixer (manufactured by Primix, "homodisper L type"). -5 and the sealing agent for each organic EL display element of Comparative Examples 1-4 were produced.
About each organic EL display element sealing agent obtained by the Example and the comparative example, it measures on conditions of 25 ° C and 100 rpm using E type viscosity meter (the Toki Sangyo Co., Ltd. make, "VISCOMETER TV-22") The viscosity and the surface tension measured by a dynamic wettability tester ("WET-6100" manufactured by Lesca Co., Ltd.) at 25 ° C are shown in Table 1.
Moreover, with respect to each sealing agent for organic EL display elements obtained by the Example and the comparative example, the film was produced by irradiating the ultraviolet-ray of wavelength 365nm with an LED lamp 3000 mJ / cm < ² >. The linear expansion coefficient of the obtained film in the temperature range of 40 ° C. to 50 ° C. was measured by a TMA apparatus (manufactured by TA Instruments, “Q400”) under the conditions of a temperature rising rate of 5 ° C./min and a force of 0.1N. . The results are shown in Table 1.

<Evaluation>
The following evaluation was performed about each sealing agent for organic EL display elements obtained by the Example and the comparative example. The results are shown in Table 1.
In addition, in each evaluation of inkjet dischargeability, wet spreadability, and reliability of an organic EL display element, as an inkjet application head, IJH-30 (manufactured by IJT) is used, and inkjet application is performed without heating. (Head temperature 25 ° C.).

(1) Ink jet coatability (1-1) Ink jet discharge property The sealing agent for organic EL display elements obtained by the Example and the comparative example is used for the ink jet discharge apparatus (The Microjet company make "NanoPrinter 500"). The solution was coated on an alkali-cleaned non-alkali glass (manufactured by Asahi Glass Co., Ltd., "AN 100") at a droplet volume of 30 picoliters. The ink jet discharge property was evaluated by regarding the case where the droplet was discharged normally from the ink jet nozzle and landed on the substrate as “o”, and the case where the droplet was not discharged normally as “x”.

(1-2) Wetting Spreadability The sealant for organic EL display elements obtained in Examples 1 to 5 and Comparative Examples 3 and 4 is used with an inkjet discharge device ("NanoPrinter 500" manufactured by Microjet, Inc.) In a drop volume of 30 picoliters, 1000 drops were applied at a speed of 5 m / s at a pitch of 500 μm onto an alkali-washed non-alkali glass ("AN 100" manufactured by Asahi Glass Co., Ltd.). The diameter of the droplet on non-alkali glass 10 minutes after application is measured, and the case where the diameter of the droplet is 150 μm or more is “o”, and the diameter of the droplet is 50 μm or more and less than 150 μm “ "B", and when the diameter of the droplet was less than 50 μm, "W" was used to evaluate the wettability and spreadability.

(2) Low Outgassing The outgassing generated at the time of heating of the cured product of the sealant for organic EL display elements obtained in Examples 1 to 5 and Comparative Examples 3 and 4 is a gas chromatograph by head space method (manufactured by JEOL Ltd. , "JMS-Q1050 GC"). 100 mg of each sealing agent for organic EL display elements was coated by an applicator to a thickness of 300 μm. Next, the sealant is cured by irradiating UV light of wavelength 365 nm with an LED lamp at 3000 mJ / cm ² , and then the cured sealant curing product is put into a head space vial to seal the vial, and the temperature is 100 ° C. The heating was performed for 30 minutes, and the generated gas was measured by the head space method.
The low outgassing properties were 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 "×" when it was 500 ppm or more.

(3) Reliability of organic EL display element (3-1) Preparation of a substrate on which a laminate having an organic light emitting material layer is disposed An ITO electrode is formed on a glass substrate (length 25 mm, width 25 mm, thickness 0.7 mm) The substrate was a film deposited to a thickness of 1000 Å. The substrate is ultrasonically cleaned with acetone, an aqueous alkaline solution, ion-exchanged water, and isopropyl alcohol for 15 minutes, respectively, and then washed with boiled isopropyl alcohol for 10 minutes, and then a UV-ozone cleaner (manufactured by Nippon Laser Electronics Co., Ltd.) The last treatment was performed with "NL-UV253").
Next, this substrate is fixed to a substrate holder of a vacuum deposition apparatus, and 200 mg of another N, N'-di (1-naphthyl) -N, N'-diphenylbenzidine (.alpha.-NPD) in an unglazed pot is prepared. The crucible was charged with 200 mg of tris (8-quinolinolato) aluminum (Alq ₃ ), and the pressure in the vacuum chamber was reduced to 1 × 10 ⁻⁴ Pa. Thereafter, the crucible containing α-NPD was heated, and α-NPD was deposited on the substrate at a deposition rate of 15 Å / s to form a hole transport layer having a film thickness of 600 Å. Next, the crucible containing Alq ₃ was heated to form an organic light emitting material layer having a film thickness of 600 Å at a 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 placed on a tungsten resistance heating boat in this vacuum deposition apparatus, and aluminum wire was placed on another tungsten boat. I put 1.0g. Thereafter, the pressure in the deposition chamber of the vacuum deposition apparatus is reduced to 2 × 10 ^-4 Pa to form lithium fluoride 5 Å at a deposition rate of 0.2 Å / s, and then aluminum is deposited at a rate of 20 Å / s and 1000 Å. did. The inside of the vaporizer was returned to normal pressure with nitrogen, and the substrate on which the laminate having the 10 mm × 10 mm organic light emitting material layer was disposed was taken out.

(3-2) Coating with Inorganic Material Film A A mask having an opening of 13 mm × 13 mm is installed to cover the entire laminate of the substrate on which the laminate obtained is obtained, and the inorganic material is plasma CVD method. A material film A was formed.
In the plasma CVD method, SiH ₄ gas and nitrogen gas are used as source gases, the flow rates are 10 sccm for SiH ₄ gas and 200 sccm for nitrogen gas, RF power is 10 W (frequency 2.45 GHz), chamber temperature is 100 ° C., chamber The internal pressure was 0.9 Torr.
The thickness of the formed inorganic material film A was about 1 μm.

(3-3) Film forming property of inorganic material film The entire surface of the obtained inorganic material film A was observed with a microscope, and no crack was observed, "○", less than 5 cracks were observed The film formability of the inorganic material film was evaluated by setting “Δ” and setting “5” or more where five or more cracks were observed.

(3-4) Formation of resin protective film The sealing agent for organic EL display elements obtained in Examples 1 to 5 and Comparative Examples 3 and 4 was used as an inkjet discharge device (Microjet Inc.) on the obtained substrate. The substrate was pattern applied using "NanoPrinter 500").
Thereafter, ultraviolet light with a wavelength of 365 nm was irradiated at 3000 mJ / cm ² using an LED lamp to cure the sealing agent for an organic EL display element, and a resin protective film was formed.

(3-5) After forming a coating resin protective film by the inorganic material film B, a mask having an opening of 12 mm × 12 mm is installed to cover the entire resin protective film, and the inorganic material is formed by plasma CVD method Film B was formed to obtain an organic EL display device.
The plasma CVD method was performed under the same conditions as the above-mentioned "coating with (3-2) inorganic material film A".
The thickness of the formed inorganic material film B was about 1 μm.

(3-6) Luminescent state of organic EL display element The organic EL display element obtained is exposed for 100 hours under an environment of temperature 85 ° C. and humidity 85%, and then a voltage of 3 V is applied to obtain the organic EL display element The light emission state (dark spots and presence or absence of quenching around the pixel) was visually observed. When there is no dark spot or peripheral quenching, uniform light emission is shown as “o”, when there is no dark spot or peripheral quenching, a slight decrease in luminance is found as Δ, when dark spot or peripheral quenching is recognized The light emission state of the organic EL display element was evaluated by setting “x” to

In order to confirm the effect on the inkjet coatability by the viscosity of the sealing agent for organic EL display elements in the non-heating type inkjet method and the heating type inkjet method, the following experiment was conducted. The results are shown in Table 2.

(Experimental example 1)
According to the compounding ratio described in Table 2, each material is uniformly stirred and mixed at a stirring speed of 3000 rpm using a homodisper type agitation mixer (manufactured by Primix, "homodispar L type"), 50 ° C, 0 A sealing agent for an organic EL display element was produced by performing a dehydration step of exposing to an environment of 1 MPa for 30 minutes.
About the obtained sealing agent for organic EL display elements, the viscosity measured on conditions of 25 degreeC and 100 rpm using E-type viscosity meter (The Toki Sangyo Co., Ltd. make, "VISCOMETER TV-22"), and 25 degreeC The surface tension was measured by a dynamic wettability tester ("WET-6100" manufactured by Lesca Co., Ltd.).
Moreover, the film was produced by irradiating 3000 mJ / cm < ² > of ultraviolet rays with a wavelength of 365 nm with the LED lamp with respect to the obtained sealing agent for organic EL display elements. The linear expansion coefficient of the obtained film in the temperature range of 40 ° C. to 50 ° C. was measured by a TMA apparatus (manufactured by TA Instruments, “Q400”) under the conditions of a temperature rising rate of 5 ° C./min and a force of 0.1N. .
Alkali-free glass (Asahi Glass Co., Ltd.) alkali-cleaned with a drop volume of 30 picoliters using the obtained sealant for an organic EL display element using an inkjet discharge device (manufactured by Microjet, “NanoPrinter 500”) , "AN100"). The ink jet discharge property was evaluated by setting the case where the droplet was normally discharged from the ink jet nozzle and landed on the substrate as “o”, and the case where the droplet was not normally discharged as “x”. In addition, as an application head for inkjet, IJH-30 (made by IJT) was used, and inkjet application was performed without heating (head temperature 25 degreeC).

(Experimental example 2)
The same sealing agent for an organic EL display element as that produced in Experimental Example 1 was prepared.
The inkjet discharge properties were evaluated in the same manner as in Experimental Example 1 except that inkjet coating was performed while heating (head temperature 60 ° C.) using IJH-30 (manufactured by IJT) as an inkjet application head.

According to the present invention, it is possible to provide a sealing agent for an organic EL display element which can be easily applied by the inkjet method, can obtain an organic EL display element excellent in low outgassing property and excellent in reliability. Can.

Claims (2)

Contains a polymerizable compound and a polymerization initiator,
The viscosity at 25 ° C is 5 to 50 mPa · s, the surface tension at 25 ° C is 15 to 35 mN / m, and the linear expansion coefficient of the cured product in the temperature range from 40 ° C to 50 ° C is 50 to 140 ppm / ° C Yes,
A sealing agent for an organic EL display element characterized by containing no solvent or having a solvent content of 0.05% by weight or less. The polymerizable compound is an epoxy compound or an oxetane compound, an organic EL display encapsulant device according to claim 1, wherein the polymerization initiator is a cationic polymerization initiator.