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 element, and an organic light-emitting display device including the same, and more particularly to a composition for sealing an organic light-emitting element that 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 element and having low dielectric constant characteristics such that touch sensitivity is improved, and an organic light-emitting display device including the same.

Description

[Technical field]

[0001] The present invention relates to a composition for sealing an organic light-emitting element, and an organic light-emitting display device including the same, and the composition not only ensures the performance and lifespan of an organic light-emitting element by effectively blocking moisture or oxygen flowing into the organic light-emitting display device from the outside, but also has 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 the organic light-emitting element have a problem in that their light-emitting characteristics and lifespan are deteriorated by moisture and oxygen from the outside. Therefore, a protective layer capable of protecting the organic materials and electrodes is required. Such a protective layer is usually formed in a structure in which one or more organic layers and inorganic layers are laminated in order to effectively block moisture and oxygen from the outside.

[0003] Recently, capacitive touch panels using organic light emitting elements have been widely adopted. Such capacitive touch panels detect touch by a change in capacitance when a conductor comes into contact with the touch panel, and in the case of a material having a high dielectric constant, a large amount of polarization occurs when an external electric field is applied, which tends to reduce touch sensitivity. Therefore, there is a demand for the development of a sealing composition for an organic layer used in a laminate structure having low dielectric constant characteristics that provide excellent touch sensitivity for touch panels. Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a composition for sealing an organic light-emitting element 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 element and also having low dielectric constant characteristics to provide excellent touch sensitivity of a touch panel, and an organic light-emitting display device including the same. [Means for solving the problem]

[0005] The present invention provides a composition for sealing an organic light-emitting element, which has been devised to solve the above problems, and is characterized in that it contains a photocurable monomer including all of the monomers represented by the following chemical formulas 1 to 3, and a photopolymerization initiator, and has a dielectric constant of 2.65 or less at a frequency range of 100 KHz to 1 MHz, and a ring parameter of 0.01 to 0.25.

[0006] [ka]

[0007] [ka]

[0008] [ka]

[0009] In the above Chemical Formula 1 to Chemical Formula 3, R1 to R5 are each independently a (meth)acryloyl group, L1 and L2 are each independently a substituted or unsubstituted C 1-10 X1 and X2 are each independently a hydrogen atom or a C 1-10 and m and n are each an integer from 1 to 4.

[0010] The organic light-emitting display device according to the present invention includes a sealing part containing the organic light-emitting element sealing composition. Effect of the Invention

[0011] When the composition for sealing an organic light-emitting element according to the present invention is used to form an encapsulation part of an organic light-emitting display device, it is possible to effectively block moisture or oxygen from entering from the outside, thereby ensuring the performance and lifespan of the organic light-emitting element, and also has an excellent touch feeling of a touch panel due to the low dielectric constant characteristic. [Brief description of the drawings]

[0012] [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 PREFERRED EMBODIMENTS

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0014] When adding reference symbols to components in each drawing, it should be noted that the same reference symbols are used as much as possible even when the same components are displayed in different drawings. In addition, in describing the present invention, if a detailed description of a related known configuration or function is considered to make the gist of the present invention unclear, the detailed description thereof will be omitted.

[0015] When a component is described as being "coupled," "bonded," or "connected" to another component, the component can be directly coupled or connected to the other component, but other components can also be "coupled," "bonded," or "connected" between each component. In addition, when a component such as a layer, film, region, or plate is described as being "on" or "on top of" another component, this includes not only the case where the component is "directly on" the other component, but also the case where there is another component between them. Conversely, when a component is described as being "directly on" another part, it means that there is no other part between them.

[0016] As used herein, the term "(meth)acrylic" means acryl and / or methacryl.

[0017] The term "alkyl group," as used herein, unless otherwise specified, means the radical of a saturated aliphatic functional group having from 1 to 60 carbons linked by a single bond, including straight-chain alkyl groups, branched-chain alkyl groups, cycloalkyl (alicyclic) groups, alkyl-substituted cycloalkyl groups, and cycloalkyl-substituted alkyl groups.

[0018] The term "alkylene group," as used herein, refers to saturated hydrocarbon-linked alkanediyl groups having no double bonds and meaning that they have two linking groups.

[0019] In addition, unless otherwise specified, the term "substituted or unsubstituted" as used herein means 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 group, C 2-20 Alkynyl groups, C 3-20 Cycloalkyl groups of C 6-20 Aryl groups, deuterium-substituted C 6-20 Aryl groups of C 8-20 an arylalkenyl group, a silane group, a boron group, and a C group containing at least one heteroatom selected from the group consisting of O, N, S, Si, and P; 2-20 Heterocyclic groups having the formula (I) and (II) may be substituted with one or more substituents selected from the group consisting of, but are not necessarily limited to, these substituents.

[0020] The term "dielectric constant" as 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.

[0021] The term "viscosity" as used herein means a value measured using a rotational viscometer for an organic layer including the composition for sealing an organic light emitting device according to the present invention.

[0022] The composition for sealing an organic light emitting device according to the present invention includes a photocurable monomer including all of the monomers represented by the following Chemical Formulas 1 to 3, and a photopolymerization initiator.

[0023] In addition, the composition for sealing an organic light emitting device according to the present invention may have a dielectric constant of 2.65 or less, a ring parameter of 0.01 to 0.25, and a viscosity of 10 to 20 cPs at a frequency range of 100 KHz to 1 MHz. For reference, the ring parameter means a value obtained by dividing the molecular weight of carbon contained in a cyclo or phenyl ring by the total molecular weight, and can be defined by the following mathematical formula 1.

[0024]

number

[0025] [ka]

[0026] [ka]

[0027] [ka]

[0028] In the above Chemical Formula 1 to Chemical Formula 3, R1 to R5 are each independently a (meth)acryloyl group, L1 and L2 are each independently a substituted or unsubstituted C 1-10 X1 and X2 are each independently a hydrogen atom or a C 1-10 and m and n are each an integer from 1 to 4.

[0029] The monomer represented by Chemical Formula 1 may be one or more 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 necessarily limited thereto.

[0030] In addition, the monomer represented by the above formula 2 may be one or more selected from the group consisting of isotetradecyl (meth)acrylate, isopentadecyl (meth)acrylate, isohexadecyl (meth)acrylate, isoheptadecyl (meth)acrylate, and isooctadecyl (meth)acrylate, but is not necessarily limited thereto.

[0031] The monomer represented by Chemical Formula 3 may be at least one selected from the group consisting of bisphenol A ethylene oxide diacrylate, bisphenol A ethylene oxide dimethacrylate, bisphenol A ethoxylate diacrylate, bisphenol A ethoxylate diacrylate, bisphenol A polyethoxylate diacrylate, and bisphenol A diacrylate, but is not necessarily limited thereto.

[0032] The photocurable monomer according to the present invention may further include at least one monomer selected from the group consisting of compounds represented by the following Formulas 4 to 6:

[0033] [ka]

[0034] [ka]

[0035] [ka]

[0036] In the above formulas 4 to 6, R6 and R7 are each independently a (meth)acryloyl group, and A is a C 1-12 and B is a substituted or unsubstituted cycloalkylene group of C6 -12and L is a direct bond or a C 1-10 Ar1 is an alkylene group of the formula: 6-60 is an aryl group of the formula

[0037] One of R8 and R9 is hydrogen and the other is a methyl group; and p is an integer from 1 to 300.

[0038] The photocurable monomer represented by the above formula 4 may be a compound represented by the following formula 7, but is not necessarily limited thereto.

[0039] [ka]

[0040] The monomer represented by the above formula 5 may be a monomer selected from the group consisting of the following formulae A-1 to A-3, but is not necessarily limited thereto.

[0041] [ka]

[0042] The photocurable monomer represented by the above formula 6 may be ethylene propylene diene monomer (EPDM).

[0043] The photocurable monomer is preferably included in an amount of 20 to 99 wt % based on the total weight of the photocurable monomer.

[0044] 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 35 wt %, the monomer represented by Chemical Formula 2 may be contained in an amount of 30 to 65 wt %, the monomer represented by Chemical Formula 3 may be contained in an amount of 1 to 30 wt %, and the monomers represented by Chemical Formulas 4 to 6 may be contained in an amount of 1 to 30 wt %, respectively.

[0045] 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 general photopolymerization initiator capable of performing a photocurable 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.

[0046] 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, for example, 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.

[0047] 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-morpholino-propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholino-phenyl)-butan-1-one, or a mixture thereof.

[0048] 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.

[0049] The thioxanthone may be thioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-chlorothioxanthone, or a mixture thereof.

[0050] 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.

[0051] The phosphorus-based compound may be bisbenzoylphenylphosphine oxide, benzoyldiphenylphosphine oxide, or a mixture thereof.

[0052] The oxime may be 2-(o-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione and 1-(o-acetyloxime)-1-[9-ethyl-6-(2-methylbenzoin)-9H-carbazol-3-yl]ethane, or a mixture thereof.

[0053] The photopolymerization initiator is preferably included 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 included in this content range, photopolymerization can occur sufficiently upon exposure to light, and it is also possible to prevent outgassing or reduced reliability due to unreacted initiator remaining after photopolymerization.

[0054] The composition for sealing an organic light-emitting device according to the present invention may further include at least one additive 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.

[0055] The composition for sealing an organic light emitting device according to the present invention has a low dielectric constant of 2.60 or less at a frequency range of 100 KHz to 1 MHz, and therefore has an excellent effect on touch sensitivity when the composition is applied to a touch panel.

[0056] Furthermore, the composition for sealing an organic light-emitting device according to the present invention preferably has a viscosity of 10 to 20 cPs, because the processability of the composition is improved within this viscosity range.

[0057] The organic light-emitting display device according to another aspect of the present invention includes a sealing part containing the organic light-emitting element sealing composition.

[0058] 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 disclosed in FIG. 1 includes a substrate 110, an organic light emitting element 200 disposed on the substrate 110, and an encapsulating unit 300 disposed on the organic light emitting element 200. Although the encapsulating unit 300 is disclosed as a multi-layer structure including a first encapsulating layer 310 and a second encapsulating layer 320, the present invention may include a structure in which the encapsulating unit 300 has two layers or four 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 lamination procedure is not limited thereto.

[0059] 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.

[0060] 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 during photocuring.

[0061] The present invention will be described in detail below with reference to examples of the composition for sealing an organic light-emitting device according to the present invention. However, the present invention is not limited to the following examples. EXAMPLES

[0062] The photocurable monomer (100 parts by weight) and the photoinitiator (TPO) (1 part by weight) shown in Table 1 below were mixed in a ratio of 1 part by weight to prepare compositions for sealing the organic light emitting device according to Examples 1 to 4.

[0063] The composition prepared above was then stirred for 12 hours and filtered through a PTFE filter with a pore size of 0.45 μm.

[0064] The filtered composition for sealing an organic light emitting device was spin-coated to a thickness of 8.0 μm or more, and then irradiated with a light amount of 1 J using a UV exposure machine to form a sealing film. The dielectric constant and viscosity were measured by the following methods.

[0065] Dielectric constant: The composition for sealing the organic light emitting device is coated on the lower electrode to a thickness of 8.0 μm or more and cured. Then, the upper electrode Ag is evaporated to a thickness of 1,000 Å. The dielectric constant of the fabricated sample was calculated after measuring it with KEYSIGHT's E4980A.

[0066] Viscosity: The viscosity of the liquid composition for sealing an organic light-emitting element was measured using a rotational viscometer.

[0067] As a result, the dielectric constant of the encapsulating film formed using the composition for sealing an organic light emitting device in Examples 1 to 4 according to the present invention was 2.60 F / m or less. This confirmed that the touch panel to which the encapsulating film prepared according to the present invention is applied has a better touch sensitivity effect.

[0068] [Table 1]

[0069] The above description is merely an illustrative description of the present invention, and a person having ordinary knowledge in the technical field to which the present invention belongs may make various modifications without departing from the essential characteristics of the present invention. Therefore, the examples disclosed in this specification are for the purpose of explanation rather than for the purpose of limiting the present invention, and the idea and scope of the present invention are not limited by such embodiments. The scope of protection of the present invention should be interpreted according to the following claims, and all technologies within the scope equivalent thereto should be interpreted as being included in the scope of the present invention. [Explanation of symbols]

[0070] 100: Substrate 200: Organic light-emitting device 300: Sealing part 310: First sealing portion 320: Second sealing part

Claims

1. A composition for sealing an organic light-emitting element, comprising: a photocurable monomer including all of the monomers represented by the following chemical formulas 1 to 3; and a photopolymerization initiator. 【Chemistry 1】 【Chemistry 2】 【Chemistry 3】 In the above Chemical Formula 1 to Chemical Formula 3, R １ From R ５ are each independently a (meth)acryloyl group, L １ and L ２ each independently represents a substituted or unsubstituted C １－１０ is an alkylene group of the formula: X １ and X ２ are each independently hydrogen or C １－１０ is an alkyl group of the formula m and n are each an integer from 1 to 4.

2. The composition for sealing an organic light-emitting element according to claim 1 , wherein the composition for sealing an organic light-emitting element has a dielectric constant of 2.65 or less at a frequency in a range of 100 Khz to 1 MHz.

3. The composition for sealing an organic light-emitting element according to claim 1 , wherein the composition for sealing an organic light-emitting element has a ring parameter of 0.01 to 0.

25.

4. 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 Formulas 4 to 6: 【Chemistry 4】 【Chemistry 5】 【Chemistry 6】 In the above Chemical Formula 4 to Chemical Formula 6, R ６ and R ７ are each independently a (meth)acryloyl group, A is a bridged ring that forms two conjugate rings. １－１２ 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 R ８ and R ９ one of which is hydrogen and the other is a methyl group, p is an integer from 1 to 300.

5. The composition for sealing an organic light-emitting device according to claim 4, wherein the photocurable monomer is contained in an amount of 20 to 99% by weight based on the total weight of the composition.

6. 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.

7. 2. The composition for sealing an organic light-emitting element 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 isooctadecyl (meth)acrylate.

8. 2. The composition for sealing an organic light-emitting element according to claim 1, wherein the monomer represented by Chemical Formula 3 is at least one selected from the group consisting of bisphenol A ethylene oxide diacrylate, bisphenol A ethylene oxide dimethacrylate, bisphenol A ethoxylate diacrylate, bisphenol A ethoxylate diacrylate, bisphenol A polyethoxylate diacrylate, and bisphenol A diacrylate.

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

10. The composition for sealing an organic light-emitting element according to claim 4, wherein the photocurable monomer represented by the above chemical formula 5 is a monomer selected from the group consisting of the following chemical formulas A-1 to A-3: 【Chemistry 8】

11. The composition for sealing an organic light emitting device according to claim 4, wherein the photocurable monomer represented by Chemical Formula 6 is ethylene propylene diene monomer (EPDM).

12. 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 triazine-based, acetophenone-based, benzophenone-based, thioxanthone-based, benzoin-based, phosphorus-based, oxime-based, and mixtures thereof.

13. 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% by weight based on the total weight of the composition.

14. 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.

15. 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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