Composition for sealing organic light-emitting device and organic light-emitting display device including the same

Abstract

The present invention relates to a composition for sealing an organic light emitting device, and an organic light emitting display device including the same. The present invention relates to a composition for sealing an organic light emitting device that can effectively block moisture or oxygen from entering an organic light emitting display device from the outside, thereby ensuring the performance and lifespan of the organic light emitting device, and also to an organic light emitting display device including the same, which has low dielectric constant characteristics such that touch sensitivity is improved.

Description

[Technical Field]

[0001] The present invention relates to a composition for sealing an organic light emitting device and an organic light emitting display device including the same, and the composition can effectively block moisture or oxygen from entering the organic light emitting display device from the outside, thereby ensuring the performance and lifespan of the organic light emitting device, and also relates to an organic light emitting device having low dielectric constant characteristics such that the touch sensitivity of a touch panel is improved, and an organic light emitting display device including the same. [Background technology]

[0002] The organic layer materials and electrodes constituting organic light-emitting devices have a problem in that their light-emitting characteristics and lifespan are deteriorated by external moisture and oxygen. Therefore, a protective layer capable of protecting the organic materials and electrodes is required. Such a protective layer is usually formed in a laminated structure of one or more organic and inorganic layers to effectively block external moisture and oxygen.

[0003] Recently, capacitive touch panels using organic light-emitting elements have been widely adopted. Capacitive touch panels detect touches based on a change in capacitance when a conductor comes into contact with the touch panel. High-dielectric constant materials tend to exhibit significant polarization when an external electric field is applied, resulting in reduced touch sensitivity. Therefore, there is a need for a sealing composition for organic layers used in stacked structures that has low dielectric constant characteristics and provides excellent touch sensitivity for touch panels. Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention aims to provide a composition for encapsulating an organic light-emitting device that can effectively block moisture or oxygen from entering an organic light-emitting display device from the outside, thereby ensuring the performance and lifespan of the organic light-emitting device, and that has low dielectric constant characteristics to provide excellent touch sensitivity of a touch panel, and an organic light-emitting display device including the composition. [Means for solving the problem]

[0005] The present invention provides a composition for sealing an organic light-emitting element, which has been made to solve the above problems, and is characterized by comprising a photocurable monomer including all of the monomers represented by the following chemical formulas 1 to 3, and a photopolymerization initiator, and having a dielectric constant of 2.60 or less at a frequency in the range of 100 KHz to 1 MHz.

[0006] [ka]

[0007] [ka]

[0008] [ka] In the above Chemical Formulas 1 to 3, R1 to R3 each independently represent a (meth)acryloyl group; R4 is a substituted or unsubstituted C 1-20 is an alkyl group of the formula m is 5 to 15, n is 1 to 10.

[0009] Another organic light-emitting display device of the present invention is characterized by containing the composition for sealing an organic light-emitting element. [Effects of the Invention]

[0010] When the encapsulating composition for organic light-emitting element according to the present invention is used to form an encapsulation part of an organic light-emitting display device, it can effectively block moisture or oxygen from entering from the outside, thereby ensuring the performance and lifespan of the organic light-emitting element. In addition, since the composition has low dielectric constant characteristics, it also has an excellent effect on the touch feeling of the touch panel. [Brief explanation of the drawings]

[0011] [Figure 1]1 is a diagram illustrating an organic light emitting display device according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0013] When referring to components in each drawing, it should be noted that the same reference numerals are used whenever possible even if the same components are shown in other drawings. Furthermore, when describing the present invention, if it is determined that a detailed description of related known structures or functions would obscure the gist of the present invention, the detailed description thereof will be omitted.

[0014] When a component is described as being "coupled," "bonded," or "connected" to another component, the component may be directly coupled or connected to the other component, or there may be other components "coupled," "bonded," or "connected" between the components. Furthermore, when a component such as a layer, film, region, or plate is described as being "on" or "above" another component, this may include not only the case where it is "directly on" the other component, but also the case where there are other components between them. Conversely, when a component is described as being "directly on" another part, it means that there are no other parts between them.

[0015] As used herein, the term "(meth)acrylic" means acryl and / or methacryl.

[0016] As used herein, unless otherwise specified, the term "alkyl group" means a radical of a saturated aliphatic functional group having 1 to 60 carbon atoms connected by single bonds, including straight-chain alkyl groups, branched-chain alkyl groups, cycloalkyl (alicyclic) groups, alkyl-substituted cycloalkyl groups, and cycloalkyl-substituted alkyl groups. The term "alkylene group" as used herein means alkanediyl groups linked by a saturated hydrocarbon having no double bonds, meaning that it has two linking groups.

[0017] Unless otherwise specified, the term "substituted or unsubstituted" used herein means any group selected from the group consisting of deuterium, halogen, amino group, nitrile group, nitro group, C 1-20 Alkyl groups of C 1-20 Alkoxy groups, C 1-20 alkylamine group, C 1-20 alkylthiophene group, C 6-20 arylthiophene group, C 2-20 Alkenyl groups of C 2-20 Alkynyl groups, C 3-20 cycloalkyl groups, C 6-20 aryl groups, deuterium-substituted C 6-20 aryl groups, C 8-20 C containing an arylalkenyl group, a silane group, a boron group, and at least one heteroatom selected from the group consisting of O, N, S, Si, and P 2-20 The term "substituted" means that the heterocyclic group may be substituted with one or more substituents selected from the group consisting of the following heterocyclic groups, but is not necessarily limited to these substituents.

[0018] The term "dielectric constant" used herein means a value measured by a capacitance method for an organic layer including the composition for sealing an organic light-emitting device according to the present invention.

[0019] The term "viscosity" as used herein means a value measured using a rotational viscometer for an organic layer containing the composition for sealing an organic light emitting device according to the present invention.

[0020] The composition for sealing an organic light-emitting element according to the present invention comprises a photocurable monomer including all of the monomers represented by the following Chemical Formulas 1 to 3, and a photopolymerization initiator: The composition may be characterized by a dielectric constant of 2.65 or less in a frequency range of 100 KHz to 1 MHz, and the viscosity of the composition may be 10 to 20 cPs.

[0021] [ka]

[0022] [ka]

[0023] [ka] In the above Chemical Formulas 1 to 3, R1 to R3 each independently represent a (meth)acryloyl group; R4 is a substituted or unsubstituted C 1-20 is an alkyl group of the formula m is 5 to 15, n is 1 to 10.

[0024] The monomer represented by Chemical Formula 1 may be at least one selected from the group consisting of 1,14-tetradecanediol di(meth)acrylate, 1,15-pentadecanediol di(meth)acrylate, 1,16-hexadecanediol di(meth)acrylate, 1,17-heptadecanediol di(meth)acrylate, and 1,18-octadecanediol di(meth)acrylate, but is not limited thereto. The weight average molecular weight of the monomer represented by Chemical Formula 1 is preferably 500 to 3,000.

[0025] In addition, the monomer represented by Chemical Formula 2 may be at least one selected from the group consisting of isotetradecyl (meth)acrylate, isopentadecyl (meth)acrylate, isohexadecyl (meth)acrylate, isoheptadecyl (meth)acrylate, and isooctadecylic (meth)acrylate, but is not necessarily limited thereto.

[0026] The monomer represented by Chemical Formula 3 may be at least one selected from the group consisting of poly-1-pentene, poly-1-hexene, poly-1-heptene, poly-1-octene, poly-1-notene, poly-1-decene, poly-1-undecene, poly-1-dodecene, poly-1-tridecene, poly-1-tetradecene, and poly-1-hexadodecene, but is not necessarily limited thereto.

[0027] The photocurable monomer according to the present invention may further include one or more monomers selected from the group consisting of compounds represented by the following Chemical Formulas 4 to 6.

[0028] [ka]

[0029] [ka]

[0030] [ka] In the Chemical Formula 4 to Chemical Formula 6, R5 to R8 are each independently a (meth)acryloyl group, and A is a C group that forms two bridged fused rings. 9-20 and B is a substituted or unsubstituted cycloalkylene group represented by C 6-12 and L is a direct bond or a C 1-10 Ar1 is an alkylene group of the formula C 6-60 is an aryl group of the formula:

[0031] The monomer represented by Chemical Formula 4 may be a compound represented by Chemical Formula 7 below (Tricyclodecanedimethanol Diacrylate, TCDDA), but is not necessarily limited thereto.

[0032] [ka] The monomer represented by Chemical Formula 5 may be a compound represented by Chemical Formula 8 below (Isobornyl Acrylate, IBOMA), but is not necessarily limited thereto.

[0033] [ka] The monomer represented by Chemical Formula 6 may be a monomer selected from the group consisting of Chemical Formulas A-1 to A-3 below, but is not necessarily limited thereto.

[0034] [ka] The content of the photocurable monomer is preferably 20 to 99% by weight based on the total weight of the composition.

[0035] More specifically, based on the total weight of the composition, the monomer represented by Chemical Formula 1 may be contained in an amount of 15 to 60 wt %, the (meth)acrylate represented by Chemical Formula 2 may be contained in an amount of 30 to 70 wt %, the monomer represented by Chemical Formula 3 may be contained in an amount of 1 to 25 wt %, and the monomers represented by Chemical Formulas 4 to 6 may be contained in an amount of 1 to 35 wt %.

[0036] The composition for sealing an organic light-emitting device according to the present invention includes a photopolymerization initiator capable of curing the photocurable monomer by UV irradiation or the like. The photopolymerization initiator is not particularly limited as long as it is a common photopolymerization initiator capable of causing a photocuring reaction. For example, the photopolymerization initiator may include a triazine-based, acetophenone-based, benzophenone-based, thioxanthone-based, benzoin-based, phosphorus-based, oxime-based, or a mixture thereof.

[0037] Examples of the triazines include 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4'-methoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, and 2-(p-tolyl)-4,6-bis(trichloromethyl)-s-triazine. The compound may be 2-(4-methoxynaphth-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-biphenyl-4,6-bis(trichloromethyl)-s-triazine, bis(trichloromethyl)-6-styryl-s-triazine, 2-(naphth-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaphth-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2,4-trichloromethyl(piperonyl)-6-triazine, 2,4-(trichloromethyl(4'-methoxystyryl)-6-triazine, or a mixture thereof.

[0038] The acetophenone may be 2,2'-diethoxyacetophenone, 2,2'-dibutoxyacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyltrichloroacetophenone, pt-butyldichloroacetophenone, 4-chloroacetophenone, 2,2'-dichloro-4-phenoxyacetophenone, 2-methyl-1-(4-(methylthio)phenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, or a mixture thereof.

[0039] The benzophenone-based compound may be benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4,4'-bis(dimethylamino)benzophenone, 4,4'-dichlorobenzophenone, 3,3'-dimethyl-2-methoxybenzophenone, or a mixture thereof.

[0040] The thioxanthone may be thioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-chlorothioxanthone, or a mixture thereof. The benzoin-based solvent may be benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, or a mixture thereof.

[0041] The phosphorus-based compound may be bisbenzoylphenylphosphine oxide, benzoyldiphenylphosphine oxide, or a mixture thereof.

[0042] The oxime may be 2-(o-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione, 1-(o-acetyloxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone, or a mixture thereof.

[0043] The photopolymerization initiator is preferably contained in an amount of 0.1 to 10 wt % based on the total weight of the composition. This is because, when the photopolymerization initiator is contained in the above content range, photopolymerization occurs sufficiently upon exposure, and outgassing and a decrease in reliability due to unreacted initiator remaining after photopolymerization can be prevented.

[0044] The composition for sealing an organic light-emitting device according to the present invention may further include one or more additives selected from the group consisting of a surfactant, a curing accelerator, and an antioxidant. In particular, the surfactant is advantageous in inducing dispersion of the composition.

[0045] The composition for sealing an organic light-emitting element according to the present invention has a low dielectric constant of 2.60 or less at a frequency in the range of 100 KHz to 1 MHz, and therefore, when the sealing composition is applied to a touch panel, it has the effect of providing very excellent touch sensitivity.

[0046] Furthermore, the composition for sealing an organic light-emitting element according to the present invention preferably has a viscosity of 10 to 20 cPs, because the processability of the composition is further improved if the viscosity is within this range.

[0047] Another organic light-emitting display device of the present invention includes a sealing part containing the organic light-emitting element sealing composition.

[0048] FIG. 1 is a diagram illustrating an organic light emitting display device according to an embodiment of the present invention. The organic light emitting display device illustrated in FIG. 1 includes a substrate 100, an organic light emitting element 200 disposed on the substrate 100, and an encapsulating unit 300 disposed on the organic light emitting element 200. While the encapsulating unit 300 is illustrated as a multilayer structure including a first encapsulating layer 310 and a second encapsulating layer 320, the present invention also encompasses structures in which the encapsulating unit 300 has two or more layers. When the encapsulating unit 300 has two layers, it may include an inorganic barrier layer and an organic barrier layer. For example, when the first encapsulating layer 310 is an inorganic barrier layer, the second encapsulating layer 320 may be an organic barrier layer, but the stacking order is not limited thereto.

[0049] The encapsulating part 300 may be formed of an organic barrier layer for sealing or encapsulating an organic light emitting display device, and the organic barrier layer may be formed by photocuring the composition for sealing an organic light emitting device according to the present invention.

[0050] The sealing composition (organic barrier layer material) may be applied by inkjet, vacuum deposition, spin coating, or slit coating, and an initiator may be used for photocuring.

[0051] The present invention will be specifically described below with reference to examples of the composition for sealing an organic light-emitting element according to the present invention, but the present invention is not limited to the following examples.

[0052] [Example] The photocurable monomer and the photoinitiator (BAPO) were mixed in the weight ratios shown in Table 1 below to prepare compositions for sealing organic light emitting devices according to Examples 1 to 4.

[0053] The prepared composition was then stirred for 12 hours and filtered through a PTFE filter with a pore size of 0.45 μm.

[0054] The filtered composition for sealing an organic light emitting device was applied by spin coating to form a film having a thickness of 8.0 μm or more, and then irradiated with a UV exposure device at a dose of 1 J to form a sealing film. The dielectric constant and viscosity were measured by the following methods.

[0055] Dielectric constant: The organic light emitting device sealing composition is coated on the lower electrode to a thickness of 8.0 μm or more and cured. Then, the upper electrode Ag is deposited to a thickness of 1,000 Å. The dielectric constant of the fabricated test specimen was calculated after measurement using a Keysight E4980A.

[0056] Viscosity: The viscosity of the liquid composition for sealing an organic light-emitting element was measured using a rotational viscometer.

[0057] As a result, the dielectric constant of the sealing films formed using the compositions for sealing organic light-emitting devices in Examples 1 to 4 according to the present invention was 2.60 F / m or less, which confirmed that a touch panel using the sealing film produced according to the present invention can achieve a better touch sensitivity effect.

[0058] [Table 1] TDMA:1,14-Tetradecanediol dimethacrylate(CAS:168473-14-1) TCDDA:Tricyclodecanedimethanol Diacrylate(CAS:42594-17-2) IBOMA:Isobornyl Acrylate(CAS:5888-33-5) ISTA:Isooctadecyl acrylate(CAS:93841-48-6) PDC:Poly 1-Decene(CAS:68037-01-4) BAPO:Bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide(CAS:162881-26-7) The above description is merely illustrative of the present invention, and various modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed herein are for illustrative purposes only, and are not intended to limit the present invention. The scope of the present invention should be interpreted by the following claims, and all technologies within the scope equivalent thereto should be interpreted as being within the scope of the present invention. [Explanation of symbols]

[0059] 100: Substrate 200: Organic light-emitting device 300: Sealing part 310: First sealing portion 320: Second sealing portion

Claims

1. The composition includes a photocurable monomer including all of the monomers represented by the following chemical formulas 1 to 3, and a photopolymerization initiator, A composition for sealing an organic light-emitting element, which has a dielectric constant of 2.65 or less at a frequency in the range of 100 Khz to 1 MHz. 【Chemistry 1】 【Chemistry 2】 【Transformation 3】 In the above Chemical Formulas 1 to 3, R １ ~R ３ are each independently a (meth)acryloyl group, R ４ is a substituted or unsubstituted C １－２０ is an alkyl group of m is 5 to 15; n is 1 to 10.

2. The composition for sealing an organic light-emitting device according to claim 1, wherein the photocurable monomer further comprises at least one monomer selected from the group consisting of compounds represented by the following Chemical Formulas 4 to 6: 【Chemistry 4】 【Transformation 5】 【Transformation 6】 In Chemical Formula 4 to Chemical Formula 6, R ５ ~R ８ are each independently a (meth)acryloyl group, A is a C group that forms two bridged fused rings. ９－２０ is a substituted or unsubstituted cycloalkylene group of the formula: B is C ６－１２ is a substituted or unsubstituted bridged cycloalkyl group of the formula: L is a direct bond or C １－１０ is an alkylene group of the formula Ar １ is C ６－６０ is an aryl group of the formula:

3. The composition for sealing an organic light emitting device according to claim 2, wherein the photocurable monomer is contained in an amount of 20 to 99 wt % based on the total weight of the composition.

4. 2. The composition for sealing an organic light-emitting device according to claim 1, wherein the monomer represented by Chemical Formula 1 is at least one selected from the group consisting of 1,14-tetradecanediol di(meth)acrylate, 1,15-pentadecanediol di(meth)acrylate, 1,16-hexadecanediol di(meth)acrylate, 1,17-heptadecanediol di(meth)acrylate, and 1,18-octadecanediol di(meth)acrylate.

5. 2. The composition for sealing an organic light-emitting device according to claim 1, wherein the monomer represented by Chemical Formula 2 is at least one selected from the group consisting of isotetradecyl (meth)acrylate, isopentadecyl (meth)acrylate, isohexadecyl (meth)acrylate, isoheptadecyl (meth)acrylate, and isooctacdecyl (meth)acrylate.

6. 2. The composition for sealing an organic light-emitting device according to claim 1, wherein the monomer represented by Chemical Formula 3 is at least one selected from the group consisting of poly-1-pentene, poly-1-hexene, poly-1-heptene, poly-1-octene, poly-1-notene, poly-1-decene, poly-1-undecene, poly-1-dodecene, poly-1-tridecene, poly-1-tetradecene, and poly-1-hexadodecene.

7. The composition for sealing an organic light emitting device according to claim 1 , wherein the photocurable monomer represented by Chemical Formula 4 is a compound represented by Chemical Formula 7: 【Transformation 7】

8. The composition for sealing an organic light emitting device according to claim 1 , wherein the photocurable monomer represented by Chemical Formula 5 is a compound represented by Chemical Formula 8: 【Transformation 8】

9. The composition for sealing an organic light-emitting element according to claim 1, wherein the photocurable monomer represented by Chemical Formula 6 is a monomer selected from the group consisting of Chemical Formulas A-1 to A-3: 【Chemistry 9】

10. 2. The composition for sealing an organic light-emitting element according to claim 1, wherein the photopolymerization initiator is at least one selected from the group consisting of triazines, acetophenones, benzophenones, thioxanthones, benzoins, phosphorus compounds, oximes, and mixtures thereof.

11. The composition for sealing an organic light-emitting element according to claim 1, wherein the photopolymerization initiator is contained in an amount of 0.1 to 10 wt % based on the total weight of the composition.

12. The composition for sealing an organic light-emitting element according to claim 1 , further comprising at least one additive selected from the group consisting of a surfactant, a curing accelerator, and an antioxidant.

13. An organic light-emitting display device comprising a sealing part containing the composition for sealing an organic light-emitting element according to claim 1 .

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