Composition for sealing organic light-emitting element and organic light-emitting display device comprising same

Abstract

The present invention relates to a composition for sealing an organic light-emitting element and an organic light-emitting display device comprising the same, and more particularly, to a composition for sealing an organic light-emitting element and an organic light-emitting display device comprising the same, the composition for sealing an organic light-emitting element and an organic light-emitting display device including the same have a low dielectric constant characteristic to improve touch sensitivity.

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 more particularly, to a composition for sealing an organic light-emitting element and an organic light-emitting display device including the same, which can ensure the performance and lifespan of an organic light-emitting element by effectively blocking moisture or oxygen entering from the outside, and which has a low dielectric constant property to improve the touch sensitivity of a touch panel. Background Art

[0002] The organic layer materials, electrodes, etc. constituting an organic light-emitting element have problems in that their light-emitting characteristics and lifespan deteriorate due to external moisture or oxygen. Therefore, a protective layer that can protect the organic materials and electrodes, etc. is required. In order to effectively block external moisture or oxygen, such a protective layer is generally formed of one or more organic layers and inorganic layers in a laminated structure.

[0003] In recent years, capacitive touch panels using organic light-emitting elements have been widely adopted. Such a capacitive touch panel senses touch by a change in capacitance when a conductor comes into contact with the touch panel. In the case of a high dielectric constant material, when an external electric field is applied, there is a tendency for the touch sensitivity to decrease due to severe polarization. Therefore, there is a need to develop a sealing composition for an organic layer used in a laminated structure having excellent touch sensitivity for a touch panel and having a low dielectric constant property. Summary of the Invention

[0004] Technical Problem

[0005] An object of the present invention is to provide a composition for sealing an organic light-emitting element and an organic light-emitting display device including the same, which can ensure the performance and lifespan of an organic light-emitting element by effectively blocking moisture or oxygen entering from the outside, and which has a low dielectric constant property to enable excellent touch sensitivity of a touch panel.

[0006] Means for Solving the Problem

[0007] The present invention is a composition for sealing an organic light-emitting element developed to solve the above problems, characterized by including a photocurable monomer and a photoinitiator, and having a dielectric constant of 2.8 or less in the frequency range of 100 Khz to 1 MHz, and the photocurable monomer simultaneously includes (meth)acrylate monomers represented by the following Chemical Formulas 1 to 4.

[0008] [Chemical Formula 1]

[0009]

[0010] [Chemical Formula 2]

[0011]

[0012] [Chemical Formula 3]

[0013] R1-L-R3

[0014] [Chemical Formula 4]

[0015] R1-L2-R4-L3-R2

[0016] In the above Chemical Formulas 1 to 4, R1 and R2 are each independently a (meth)acryloyl group, R3 is a substituted or unsubstituted C 6-12 bridged cycloalkyl group, R4 is a substituted or unsubstituted C 6-12 bridged sub-cycloalkyl group, L1 to L3 are each independently a single bond or an alkylene group, n is from 14 to 18, and m is from 5 to 15.

[0017] The viscosity of the composition for sealing an organic light-emitting element may be 10 to 30 cPs.

[0018] Based on the total weight of the composition, the content of the above photocurable monomer may be 20 to 99% by weight.

[0019] The (meth)acrylate monomer represented by the above 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.

[0020] The (meth)acrylate monomer represented by the above Chemical Formula 2 may be one or more selected from the group consisting of isomyristyl (meth)acrylate, isopentadecyl (meth)acrylate, isohexadecyl (meth)acrylate, isooctadecyl (meth)acrylate, and isooctadecyl (meth)acrylate.

[0021] The (meth)acrylate monomer represented by the above Chemical Formula 3 may be one or more selected from the group consisting of isobornyl (meth)acrylate, norbornene methyl (meth)acrylate, 3-methyl-2-norbornene methyl (meth)acrylate, dicyclopentene (meth)acrylate, dicyclopentenoxyethyl (meth)acrylate, dicyclopentyl (meth)acrylate, tricyclodecyl (meth)acrylate, and adamantyl (meth)acrylate.

[0022] The (meth)acrylate monomer represented by the above chemical formula 4 may be one or more selected from the group consisting of bicyclo[1.1.1]pentane di(meth)acrylate, bicyclo[2.1.1]heptane di(meth)acrylate, tricyclodecane di(meth)acrylate, pentacyclopentadecane di(meth)acrylate, adamantane di(meth)acrylate, and norbornane di(meth)acrylate.

[0023] The above photoinitiator may be one or more selected from the group consisting of triazine-based, acetophenone-based, benzophenone-based, thioxanthone-based, benzoin-based, phosphorus-based, oxime-based, and mixtures thereof.

[0024] Based on the total weight of the composition, the content of the above photoinitiator may be 0.1 to 10% by weight.

[0025] The above composition for sealing an organic light-emitting element may further contain one or more additives selected from the group consisting of surfactants, curing accelerators, and antioxidants.

[0026] Another aspect of the present invention is an organic light-emitting display device, characterized by comprising a sealing portion containing the above composition for sealing an organic light-emitting element.

[0027] Advantages of the Invention

[0028] When the composition for sealing an organic light-emitting element of the present invention is used to form a sealing portion of an organic light-emitting display device, the following effects are achieved: not only can the performance and lifespan of the organic light-emitting element be ensured by effectively blocking moisture or oxygen entering from the outside, but also it has a low dielectric constant property, so the touch sensitivity of the touch panel is excellent. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is an illustrative view of an organic light-emitting display device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0030] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0031] When assigning reference numerals to the components of each drawing, it should be noted that even if the same components are marked with the same reference numerals in different drawings, the same reference numerals are preferably assigned as much as possible. In addition, when describing the present invention, if a detailed description of a related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

[0032] When a certain component is described as "connected", "bonded" or "joined" to another component, the component may be directly connected or joined to the other component, but there may also be other components "connected", "bonded" or "joined" between the components. In addition, when a component such as a layer, film, region, plate, etc. is described as being "above" or "on" another component, it includes not only the case where it is directly "above" the other component, but also the case where there are other components in between. On the contrary, when a certain component is described as being directly "above" another component, it means that there is no other part in between.

[0033] As used herein, the term "(meth)acryloyl" means "acryloyl" and / or "methacryloyl".

[0034] As used herein, the term "alkyl" unless otherwise specified refers to a saturated aliphatic functional group radical having 1 to 60 carbons connected by single bonds, represented by straight-chain alkyl, branched-chain alkyl, cycloalkyl (alicyclic group), alkyl-substituted cycloalkyl, and cycloalkyl-substituted alkyl.

[0035] As used herein, the term "alkylene" refers to alkanediyl groups formed by connecting saturated hydrocarbons without double bonds and having two linking groups.

[0036] In addition, unless otherwise clearly specified, the term "substituted or unsubstituted" as used herein, "substituted" means that it can be substituted by one or more substituents selected from the group consisting of deuterium, halogen, amino, nitrile, nitro, C 1-20 alkyl, C 1-20 alkoxy, C 1-20 alkylamino, C 1-20 alkylthienyl, C 6-20 arylthienyl, C 2-20 alkenyl, C 2-20 alkynyl, C 3-20 cycloalkyl, C 6-20 aryl, deuterium-substituted C 6-20 aryl, C 8-20 arylenyl, silyl, boron group, and C 2-20 heterocyclic group containing at least one heteroatom selected from the group consisting of O, N, S, Si, and P, but is not necessarily limited to these substituents.

[0037] As used herein, the term "dielectric constant" refers to the value measured by the capacitance method for the organic layer of the above-mentioned organic light-emitting element sealing composition containing the present invention.

[0038] As used in this specification, the term "viscosity" refers to the value measured for the organic layer of the organic light-emitting element sealing composition containing the present invention using a rotational viscometer.

[0039] The organic light-emitting element sealing composition of the present invention is characterized by containing a photocurable monomer and a photoinitiator, having a dielectric constant of 2.8 or less at a frequency in the range of 100 kHz to 1 MHz, the photocurable monomer simultaneously containing (meth)acrylate monomers represented by the following Chemical Formulas 1 to 4, and the viscosity of the composition can be 10 to 30 cPs.

[0040] The above photocurable monomer contains all monomers including a di(meth)acrylate represented by the following Chemical Formula 1, a mono(meth)acrylate represented by the following Chemical Formula 2, and a mono(meth)acrylate represented by the following Chemical Formula 3.

[0041] [Chemical Formula 1]

[0042]

[0043] [Chemical Formula 2]

[0044]

[0045] [Chemical Formula 3]

[0046] R1-L-R3

[0047] [Chemical Formula 4]

[0048] R1-L2-R4-L3-R2

[0049] In the above Chemical Formulas 1 to 4,

[0050] R1 and R2 are each independently a (meth)acryloyl group,

[0051] R3 is a substituted or unsubstituted C 6-12 bridged cycloalkyl,

[0052] R4 is a substituted or unsubstituted C 6-12 bridged sub-cycloalkyl,

[0053] L1 to L3 are each independently a single bond or an alkylene group

[0054] n is 14 to 18,

[0055] m is 5 to 15.

[0056] Based on the total weight of the above photocurable monomer, the content of the photocurable monomer is preferably 20 to 99% by weight.

[0057] More specifically, the (meth)acrylate monomer represented by the above 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.

[0058] In addition, the (meth)acrylate monomer represented by the above chemical formula 2 may be one or more selected from the group consisting of isomyristyl (meth)acrylate, isopentadecyl (meth)acrylate, isohexadecyl (meth)acrylate, isopheptadecyl (meth)acrylate, and isooctadecyl (meth)acrylate, but is not necessarily limited thereto.

[0059] The (meth)acrylate monomer represented by the above chemical formula 3 may be one or more selected from the group consisting of isobornyl (meth)acrylate, norbornene methyl (meth)acrylate, 3-methyl-2-norbornene methyl (meth)acrylate, dicyclopentene (meth)acrylate, dicyclopentenoxyethyl (meth)acrylate, dicyclopentyl (meth)acrylate, tricyclodecyl (meth)acrylate, and adamantyl (meth)acrylate, but is not necessarily limited thereto.

[0060] The (meth)acrylate monomer represented by the above chemical formula 4 may be one or more selected from the group consisting of bicyclo[1.1.1]pentane di(meth)acrylate, bicyclo[2.1.1]heptane di(meth)acrylate, tricyclodecane di(meth)acrylate, pentacyclopentadecane di(meth)acrylate, adamantane di(meth)acrylate, and norbornane di(meth)acrylate, but is not necessarily limited thereto.

[0061] The composition for sealing an organic light-emitting element of the present invention contains a photoinitiator that can cure the above photocurable monomer by UV irradiation or the like. The photoinitiator is not particularly limited as long as it is a usual photoinitiator that can perform a photocuring reaction. As an example, the photoinitiator may include a triazine-based, acetophenone-based, benzophenone-based, thioxanthone-based, benzoin-based, phosphorus-based, oxime-based, or a mixture thereof.

[0062] As the above-mentioned triazine series, it can be 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, 2-(p-tolyl)-4,6-bis(trichloromethyl)-s-triazine, 2-biphenyl-4,6-bis(trichloromethyl)-s-triazine, bis(trichloromethyl)-6-styryl-s-triazine, 2-(naphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2,4-trichloromethyl(piperonyl)-6-triazine, 2,4-(trichloromethyl(4'-methoxystyryl)-6-triazine or their mixtures.

[0063] As the above-mentioned acetophenone series, it can be 2,2'-diethoxyacetophenone, 2,2'-dibutoxyacetophenone, 2-

[0230] hydroxy-2-methylpropiophenone, p-tert-butyltrichloroacetophenone, p-tert-butyldichloroacetophenone, 4-chloro

[0231] acetophenone, 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 their mixtures.

[0064] As the above-mentioned benzophenone series, it can 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 their mixtures.

[0065] As the above-mentioned thioxanthone series, it can be thioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-chlorothioxanthone or their mixtures.

[0066] As the above-mentioned benzoin series, it can be benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzil dimethyl ketal or their mixtures.

[0067] As the above-mentioned phosphorus series, it can be bis(benzoylphenyl)phosphine oxide, benzoyldiphenylphosphine oxide or their mixtures.

[0068] As the above-mentioned oxime-based compounds, they can be 2-(o-benzoylhydroxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione and 1-(o-acetohydroxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone, or a mixture thereof.

[0069] Based on the total weight of the composition, the content of the above-mentioned photoinitiator is preferably 0.1 to 10% by weight. This is because when the photoinitiator is included in the above content range, not only can sufficient photopolymerization occur during exposure, but also the generation of outgas and the reduction of reliability due to the unreacted initiator remaining after photopolymerization can be prevented.

[0070] The composition for sealing an organic light-emitting element of the present invention may further contain one or more additives selected from the group consisting of surfactants, curing accelerators, and antioxidants. In particular, surfactants are beneficial for inducing the dispersion of the composition.

[0071] The composition for sealing an organic light-emitting element of the present invention has a low dielectric constant characteristic with a dielectric constant of 2.8 or less in the frequency range of 100 kHz to 1 MHz. Therefore, when the above-mentioned sealing composition is applied to a touch panel, it has an excellent touch sensitivity effect.

[0072] In addition, the viscosity of the composition for sealing an organic light-emitting element of the present invention is preferably 10 to 30 cPs because the processability of the composition can be further improved within the above viscosity range.

[0073] Another aspect of the present invention is an organic light-emitting display device, which includes a sealing portion containing the above-mentioned composition for sealing an organic light-emitting element.

[0074] Figure 1 It is an exemplary diagram of an organic light-emitting display device according to an embodiment of the present invention. Figure 1 The disclosed organic light-emitting display device includes a substrate 110, an organic light-emitting element 200 disposed on the substrate 110, and a sealing portion 300 disposed on the organic light-emitting element 200. At this time, the above-mentioned sealing portion 300 is a multilayer composed of a first sealing layer 310 and a second sealing layer 320. However, the present invention may include all configurations in which the sealing portion 300 has two or four or more layers. When the sealing portion 300 is composed of a two-layer multilayer, it may include an inorganic barrier layer and an organic barrier layer. For example, when the first sealing layer 310 is an inorganic barrier layer, the second sealing layer 320 may be an organic barrier layer, but the stacking order is not limited thereto.

[0075] The above-mentioned sealing portion 300 can form an organic barrier layer for the sealing or encapsulation of the organic light-emitting display device, and the organic barrier layer can be formed by photocuring the composition for sealing an organic light-emitting element of the present invention.

[0076] The above sealing composition (organic barrier layer material) can be coated by inkjet, vacuum evaporation, spin coating or slot die coating methods, and an initiator can be used during photocuring.

[0077] Hereinafter, examples of the composition for sealing an organic light-emitting element of the present invention will be given to specifically illustrate the present invention, but the present invention is not limited by the following examples.

[0078] [Examples]

[0079] Compositions for sealing an organic light-emitting element of Examples 1 to 3 and Comparative Examples 1 to 6 were manufactured by mixing according to the weight ratios of photocurable monomers and photoinitiator (BAPO) described in Table 1 below.

[0080] Then, the compositions manufactured above were stirred for 12 hours and filtered using a PTFE filter with a pore size of 0.45 μm.

[0081] The filtered composition for sealing an organic light-emitting element was formed into a thickness of 8.0 μm or more by spin coating, 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.

[0082] Dielectric constant: The composition for sealing an organic light-emitting element was coated on the lower electrode with a thickness of 8.0 μm or more and cured. Then, the upper electrode Ag was deposited with a thickness. The dielectric constant was calculated after measuring the fabricated test piece using E4980A of Keysight Technologies.

[0083] Viscosity: The viscosity of the liquid composition for sealing an organic light-emitting element was measured using a rotational viscometer.

[0084] As a result, the dielectric constants of the sealing films formed from the compositions for sealing an organic light-emitting element of Examples 1 to 2 of the present invention were all 2.8 F / m or less, but the dielectric constants of the sealing films formed from Comparative Examples 1 to 6 were greater than 2.8 F / m. Therefore, it was confirmed that a touch panel using the sealing film manufactured according to the present invention can achieve a more excellent touch sensitivity effect.

[0085] [Table 1]

[0086]

[0087] TDMA: 1,14-Tetradecanediol dimethacrylate (CAS: 168473-14-1)

[0088] TCDDA: Tricyclodecanedimethanol diacrylate (CAS: 42594-17-2)

[0089] IBOMA: Isobornyl Acrylate (CAS: 5888-33-5)

[0090] ADMA: 1-Adamantyl Methacrylate (CAS: 16887-36-8)

[0091] ISTA: Isooctadecyl acrylate (CAS: 93841-48-6)

[0092] BAPO: Bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide (CAS: 162881-26-7)

[0093] The above description is only an illustrative description of the present invention. Those of ordinary skill in the technical field to which the present invention pertains should be able to make various changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in this specification are intended to illustrate rather than limit the present invention, and the idea and scope of the present invention will not be limited by these embodiments. The protection scope of the present invention should be interpreted according to the scope of the appended claims, and all technologies within the equivalent scope should be interpreted as being included within the scope of the claims of the present invention.

[0094] Symbol Explanation

[0095] 100: Substrate

[0096] 200: Organic light-emitting element

[0097] 300: Sealing portion

[0098] 310: First sealing portion

[0099] 320: Second sealing portion

Claims

1. A composition for sealing an organic light-emitting element, which contains a photocurable monomer and a photoinitiator and has a dielectric constant of 2.8 or less at a frequency in the range of 100 kHz to 1 MHz. The photocurable monomer simultaneously contains (meth)acrylate monomers represented by the following Chemical Formulas 1 to 4. [Chemical Formula 1] [Chemical Formula 2] [Chemical Formula 3] R1-L-R3 [Chemical Formula 4] R1-L2-R4-L3-R2 In the above Chemical Formulas 1 to 4, R1 and R2 are each independently a (meth)acryloyl group. R3 is a substituted or unsubstituted C 6-12 bridged cycloalkyl group, R4 is a substituted or unsubstituted C 6-12 bridged subcycloalkyl group, L1 to L3 are each independently a single bond or an alkylene group. n is 14 to 18. m is 5 to 15.

2. The composition for sealing an organic light-emitting element according to claim 1, wherein the viscosity of the composition for sealing an organic light-emitting element is 10 to 30 cPs.

3. The composition for sealing an organic light-emitting element according to claim 1, wherein the content of the photocurable monomer is 20 to 99% by weight based on the total weight of the composition.

4. The composition for sealing an organic light-emitting element according to claim 1, wherein the (meth)acrylate monomer represented by Chemical Formula 1 is 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.

5. The composition for sealing an organic light-emitting element according to claim 1, wherein the (meth)acrylate monomer represented by Chemical Formula 2 is one or more selected from the group consisting of isomyristyl (meth)acrylate, isopentadecyl (meth)acrylate, isohexadecyl (meth)acrylate, isheptadecyl (meth)acrylate, and isooctadecyl (meth)acrylate.

6. The composition for sealing an organic light-emitting element according to claim 1, wherein the (meth)acrylate monomer represented by Chemical Formula 3 is one or more selected from the group consisting of isobornyl (meth)acrylate, norbornene methyl (meth)acrylate, 3-methyl-2-norbornene methyl (meth)acrylate, dicyclopentene (meth)acrylate, dicyclopentenoxyethyl (meth)acrylate, dicyclopentyl (meth)acrylate, tricyclodecyl (meth)acrylate, and adamantyl (meth)acrylate.

7. The composition for sealing an organic light-emitting element according to claim 1, wherein the (meth)acrylate monomer represented by Chemical Formula 4 is one or more selected from the group consisting of bicyclo[1.1.1]pentane di(meth)acrylate, bicyclo[2.1.1]heptane di(meth)acrylate, tricyclodecane di(meth)acrylate, pentacyclopentadecane di(meth)acrylate, adamantane di(meth)acrylate, and norbornane di(meth)acrylate.

8. The composition for sealing an organic light-emitting element according to claim 1, wherein the photoinitiator is one or more selected from the group consisting of triazine-based, acetophenone-based, benzophenone-based, thioxanthone-based, benzoin-based, phosphorus-based, oxime-based, and mixtures thereof.

9. The composition for sealing an organic light-emitting element according to claim 1, wherein the content of the photoinitiator is 0.1 to 10% by weight based on the total weight of the composition.

10. The composition for sealing an organic light-emitting element according to claim 1, wherein the composition for sealing an organic light-emitting element further comprises one or more additives selected from the group consisting of surfactants, curing accelerators, and antioxidants.

11. An organic light-emitting display device comprising a sealing portion containing the composition according to any one of claims 1 to 10.

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