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, which can not only ensure the performance and lifespan of the organic light-emitting element by effectively blocking moisture or oxygen entering from the outside into the organic light-emitting display device, but also has a low dielectric constant property to improve the touch sensitivity of a touch panel, and an organic light-emitting display device including the same. Background Art

[0002] There are problems that the light-emitting characteristics and lifespan of the organic layer materials, electrodes, etc. constituting the organic light-emitting element 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 usually 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, it is necessary to develop a sealing composition for an organic layer used in a laminated structure having excellent touch sensitivity of 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 the organic light-emitting element by effectively blocking moisture or oxygen entering from the outside into the organic light-emitting display device, and has a low dielectric constant property to make the touch sensitivity of the touch panel excellent.

[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 in that it contains a photocurable monomer and a photoinitiator, and has a dielectric constant of 2.9 or less in the frequency range of 100 Khz to 1 MHz, and the photocurable monomer simultaneously contains (meth)acrylates represented by the following Chemical Formulas 1 to 3.

[0008] [Chemical Formula 1]

[0009]

[0010] [Chemical Formula 2]

[0011]

[0012] [Chemical Formula 3]

[0013] R1—L—R3

[0014] In the above Chemical Formulas 1 to 3, R1 to R3 are each independently a (meth)acryloyl group, R4 is a substituted or unsubstituted C 6-12 bridged cycloalkyl group, L is a single bond or an alkylene group, n is 14 to 18, and m is 5 to 15.

[0015] The viscosity of the composition for sealing an organic light-emitting element may be 10 to 30 cPs.

[0016] Based on the total weight of the composition, the content of the above photocurable monomer may be 20 to 99% by weight.

[0017] The (meth)acrylate 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.

[0018] The (meth)acrylate 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.

[0019] The (meth)acrylate 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.

[0020] 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.

[0021] Based on the total weight of the composition, the content of the above photoinitiator may be 0.1 to 10% by weight.

[0022] The 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.

[0023] Another invention is an organic light-emitting display device, characterized by comprising a sealing portion containing the above-described composition for sealing an organic light-emitting element.

[0024] Advantages of the Invention

[0025] 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 advantages are obtained: 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, and thus the touch sensitivity of the touch panel is excellent. Description of the Drawings

[0026] Figure 1 is an exemplary view of an organic light-emitting display device according to an embodiment of the present invention. Detailed Description of the Invention

[0027] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0028] When assigning reference numerals to the components of each drawing, it should be noted that even if the same components are denoted by 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.

[0029] When a certain component is described as "connected", "joined", or "adjoined" to another component, the component may be directly connected or adjoined to the other component, but there may also be other components "connected", "joined", or "adjoined" between the components. In addition, when a component such as a layer, film, region, or plate 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 therebetween. 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.

[0030] As used in this specification, the term "(meth)acryloyl" means "acryloyl" and / or "methacryloyl".

[0031] As used in this specification, the term "alkyl" refers to a saturated aliphatic functional group radical having 1 to 60 carbons connected by single bonds, represented by linear alkyl, branched alkyl, cycloalkyl (alicyclic group), alkyl-substituted cycloalkyl, and cycloalkyl-substituted alkyl, unless otherwise specified.

[0032] As used herein, the term "alkylene" refers to alkanediyl groups that are formed by connecting saturated hydrocarbons without double bonds and have two linking groups.

[0033] In addition, unless otherwise clearly stated, the term "substituted or unsubstituted" as used herein, "substituted" means that it can be 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 arylalkenyl, silyl, boranyl, and C containing at least one heteroatom selected from the group consisting of O, N, S, Si, and P 2-20 heterocyclic group, and is substituted by one or more substituents from the group, but is not necessarily limited to these substituents.

[0034] As used herein, the term "dielectric constant" refers to the value measured for the organic layer of the above-mentioned organic light-emitting element sealing composition containing the present invention by the capacitance method.

[0035] As used herein, the term "viscosity" refers to the value measured for the organic layer of the above-mentioned organic light-emitting element sealing composition containing the present invention using a rotational viscometer.

[0036] The organic light-emitting element sealing composition of the present invention is characterized in that it contains a photocurable monomer and a photoinitiator, and has a dielectric constant of 2.9 or less at a frequency in the range of 100 kHz to 1 MHz. The above-mentioned photocurable monomer simultaneously contains (meth)acrylates represented by the following Chemical Formulas 1 to 3, and the viscosity of the above-mentioned composition can be 10 to 30 cPs.

[0037] The above-mentioned photocurable monomer simultaneously contains 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.

[0038] [Chemical Formula 1]

[0039]

[0040] [Chemical Formula 2]

[0041]

[0042] [Chemical Formula 3]

[0043] R1—L—R3

[0044] In the above Chemical Formulas 1 to 3,

[0045] each of R1 to R3 is independently a (meth)acryloyl group,

[0046] R4 is a substituted or unsubstituted C 6-12 bridged cycloalkyl group,

[0047] L is a single bond or an alkylene group,

[0048] n is from 14 to 18,

[0049] m is from 5 to 15.

[0050] Based on the total weight of the composition, the content of the above photocurable monomer is preferably 20 to 99% by weight.

[0051] 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.

[0052] 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, isheptadecyl (meth)acrylate, and isooctadecyl (meth)acrylate, but is not necessarily limited thereto.

[0053] 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.

[0054] The composition for sealing an organic light-emitting element of the present invention contains a photoinitiator that can cure the above-mentioned photocurable monomer by UV irradiation or the like. The above-mentioned photoinitiator is not particularly limited as long as it is a general photoinitiator that can perform a photocuring reaction. As an example, the above-mentioned photoinitiator may include triazine-based, acetophenone-based, benzophenone-based, thioxanthone-based, benzoin-based, phosphorus-based, oxime-based, or a mixture thereof.

[0055] As the above-mentioned triazine-based, it may 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 a mixture thereof.

[0056] As the above-mentioned acetophenone-based, it may 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 a mixture thereof.

[0057] As the above-mentioned benzophenone-based, it 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.

[0058] As the above-mentioned thioxanthone-based, it may be thioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-chlorothioxanthone, or a mixture thereof.

[0059] As the above-mentioned benzoin-based, it may be benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzil dimethyl ketal, or a mixture thereof.

[0060] As the above-mentioned phosphorus-based compounds, they can be bis(benzoyl)phenylphosphine oxide, benzoyldiphenylphosphine oxide, or a mixture thereof.

[0061] As the above-mentioned oxime-based compounds, they can be 2-(o-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione and 1-(o-acetoxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone, or a mixture thereof.

[0062] 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.

[0063] 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.

[0064] The composition for sealing an organic light-emitting element of the present invention has a low dielectric constant characteristic with a dielectric constant of 2.9 or less in the frequency range of 100Khz to 1MHz. Therefore, when the above-mentioned sealing composition is applied to a touch panel, it has an excellent touch sensitivity effect.

[0065] 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.

[0066] 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.

[0067] 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 lamination order is not limited thereto.

[0068] The above-mentioned sealing part 300 can form an organic barrier layer for the sealing or encapsulation of an 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.

[0069] The above-mentioned composition for sealing (organic barrier layer material) can be coated by inkjet, vacuum evaporation, spin coating or slot coating methods, and an initiator can be used during photocuring.

[0070] 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.

[0071] [Examples]

[0072] Compositions for sealing organic light-emitting elements 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.

[0073] Then, the above-prepared composition was stirred for 12 hours and filtered using a PTFE filter with a pore size of 0.45 μm.

[0074] The above-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.

[0075] 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.

[0076] Viscosity: The viscosity of the liquid composition for sealing an organic light-emitting element was measured using a rotational viscometer.

[0077] As a result, the dielectric constants of the sealing films formed from the compositions for sealing organic light-emitting elements of Examples 1 to 3 of the present invention all obtained values of 2.9 F / m or less, but the dielectric constants of the sealing films formed from Comparative Examples 1 to 6 were greater than 2.9 F / m. Therefore, it was confirmed that a touch panel applying the sealing film manufactured according to the present invention can obtain a more excellent touch sensitivity effect.

[0078] [Table 1]

[0079]

[0080] TDMA: 1,14 - Tetradecanediol dimethacrylate (CAS: 168473 - 14 - 1)

[0081] HDDMA: 1,6 - Hexanediol dimethacrylate (CAS: 6606 - 59 - 3)

[0082] IBOMA: Isobornyl Acrylate (CAS: 5888 - 33 - 5)

[0083] ISTA: Isooctadecyl acrylate (CAS: 93841 - 48 - 6)

[0084] IOA: Isooctyl acrylate (CAS: 29590 - 42 - 9)

[0085] IDA: Isodecyl acrylate (CAS: 1330 - 61 - 6)

[0086] SA: Stearyl Acrylate (CAS: 4813 - 57 - 4)

[0087] OA: Octyl acrylate (CAS: 90530 - 31 - 7)

[0088] DA: Dodecyl Acrylate (CAS: 2156 - 97 - 0)

[0089] BAPO: Bis(2,4,6 - trimethyl benzoyl) - phenylphosphine oxide (CAS: 162881 - 26 - 7)

[0090] The above description is only an illustrative description of the present invention. Any person 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.

[0091] [Description of Reference Numerals]

[0092] 100: Substrate

[0093] 200: Organic light-emitting element

[0094] 300: Sealing portion

[0095] 310: First sealing portion

[0096] 320: Second sealing portion

Claims

1. An organic light-emitting element sealing composition, which contains a photocurable monomer and a photoinitiator, and has a dielectric constant of 2.9 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, 2, and 3. [Chemical Formula 1] [Chemical Formula 2] [Chemical Formula 3] R1——L——R3 In the above Chemical Formulas 1 to 3, R1 and R2 are each independently a (meth)acryloyl group. R3 is a substituted or unsubstituted C 6-12 bridged cycloalkyl group, L is a single bond or an alkylene group. n is from 14 to 18. m is from 5 to 15.

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

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

4. The organic light-emitting element sealing composition 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 organic light-emitting element sealing composition 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, isoseptadecyl (meth)acrylate, and isooctadecyl (meth)acrylate.

6. The organic light-emitting element sealing composition 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 organic light-emitting element sealing composition 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.

8. The organic light-emitting element sealing composition according to Claim 1, wherein, based on the total weight of the composition, the content of the photoinitiator is from 0.1 to 10% by weight.

9. The organic light-emitting element sealing composition according to Claim 1, wherein the organic light-emitting element sealing composition further contains one or more additives selected from the group consisting of surfactants, curing accelerators, and antioxidants.

10. An organic light-emitting display device, which includes a sealing portion containing the composition according to any one of Claims 1 to 9.

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