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 is a problem that the organic layer materials, electrodes, etc. constituting the organic light-emitting element deteriorate in their light-emitting characteristics and lifespan 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 by including a photocurable monomer and a photoinitiator, and having a dielectric constant of 2.65 or less in the frequency range of 100Khz to 1MHz, and the above photocurable monomer simultaneously includes 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] R3-L1-R4

[0014] [Chemical Formula 4]

[0015]

[0016] In the above Chemical Formulas 1 to 4, each of R1 to R3 is independently a (meth)acryloyl group, R4 is a substituted or unsubstituted C 6-12 bridged cycloalkyl group, R5 is a vinyl group or a (meth)acryloyl group, L is a single bond or an alkylene group, n is from 14 to 18, m is from 5 to 15, and p is from 0 to 10.

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

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

[0019] 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.

[0020] 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.

[0021] 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.

[0022] The monomer represented by the above Chemical Formula 4 may be the monomer represented by the following Chemical Formula 5 or Chemical Formula 6.

[0023] [Chemical Formula 5]

[0024]

[0025] [Chemical Formula 6]

[0026]

[0027] The above-mentioned 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.

[0028] Based on the total weight of the composition, the content of the above-mentioned photoinitiator may be 0.1 to 10% by weight.

[0029] The above-mentioned 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.

[0030] Another aspect of the present invention is an organic light-emitting display device, characterized by comprising a sealing portion containing the above-mentioned composition for sealing an organic light-emitting element.

[0031] Advantages of the Invention

[0032] When using the composition for sealing an organic light-emitting element of the present invention to form the 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

[0033] Figure 1 It is an illustrative diagram of an organic light-emitting display device according to an embodiment of the present invention. Detailed Description of the Embodiments

[0034] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0035] 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 should be assigned as much as possible. In addition, when describing the present invention, if the specific description of related well-known components or functions may obscure the gist of the present invention, the detailed description thereof will be omitted.

[0036] 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 components such as layers, films, regions, plates, etc. are described as being "above" or "on" other components, it includes not only the case where they are directly "above" the other components, 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.

[0037] As used herein, the term "(meth)acryloyl" refers to acryloyl and / or methacryloyl.

[0038] 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 linear alkyl, branched alkyl, cycloalkyl (alicyclic group), alkyl-substituted cycloalkyl, and cycloalkyl-substituted alkyl.

[0039] As used herein, the term "alkylene" refers to alkanediyl groups formed by connecting saturated hydrocarbons without double bonds and having two linking groups.

[0040] 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 containing at least one heteroatom selected from the group consisting of O, N, S, Si, and P 2-20 heterocyclic group, but is not necessarily limited to these substituents.

[0041] As used herein, the term "dielectric constant" refers to the value measured by the capacitance method for the organic layer containing the composition for sealing an organic light-emitting element of the present invention.

[0042] 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.

[0043] 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 2.65 or less in the frequency range of 100 kHz to 1 MHz, the photocurable monomer simultaneously containing (meth)acrylate monomers represented by the following Chemical Formulas 1, 2, and 3, and the viscosity of the composition may be 10 to 30 cPs.

[0044] An organic light-emitting element sealing composition containing a photocurable monomer and a photoinitiator, having a dielectric constant of 2.65 or less in the frequency range of 100 kHz to 1 MHz, the photocurable monomer simultaneously containing (meth)acrylates represented by the following Chemical Formulas 1 to 4:

[0045] [Chemical Formula 1]

[0046]

[0047] [Chemical Formula 2]

[0048]

[0049] [Chemical Formula 3]

[0050] R3-L1-R4

[0051] [Chemical Formula 4]

[0052]

[0053] In the above Chemical Formulas 1 to 4,

[0054] R1 to R3 are each independently a (meth)acryloyl group,

[0055] R4 is a substituted or unsubstituted C 6-12 bridged cycloalkyl,

[0056] R5 is a vinyl group or a (meth)acryloyl group,

[0057] L is a single bond or an alkylene group,

[0058] n is 14 to 18,

[0059] m is 5 to 15,

[0060] p is 0 to 10.

[0061] Based on the total weight of the photocurable monomer, the content of the photocurable monomer is preferably 20 to 99% by weight.

[0062] More specifically, 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, but is not necessarily limited thereto.

[0063] In addition, 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, isoseptadecyl (meth)acrylate, and isooctadecyl (meth)acrylate, but is not necessarily limited thereto.

[0064] 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, dicyclopentenyl (meth)acrylate, dicyclopentenoxyethyl (meth)acrylate, dicyclopentyl (meth)acrylate, tricyclodecanyl (meth)acrylate, and adamantyl (meth)acrylate, but is not necessarily limited thereto.

[0065] The monomer represented by the above Chemical Formula 4 may be the monomer represented by the following Chemical Formula 5 or Chemical Formula 6, but is not necessarily limited thereto.

[0066] [Chemical Formula 5]

[0067]

[0068] [Chemical Formula 6]

[0069]

[0070] The composition for sealing an organic light-emitting element of the present invention contains a photopolymerization initiator that can cure the above photocurable monomer by UV irradiation or the like. The above photopolymerization initiator is not particularly limited as long as it is a general photopolymerization initiator that can perform a photocuring reaction. As an example, the above photopolymerization initiator may include a triazine-based, acetophenone-based, benzophenone-based, thioxanthone-based, benzoin-based, phosphorus-based, oxime-based, or a mixture thereof.

[0071] 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 mixture.

[0072] 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 mixture.

[0073] 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 mixture.

[0074] As the above-mentioned thioxanthone series, it can be thioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-chlorothioxanthone or their mixture.

[0075] 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 mixture.

[0076] As the above-mentioned phosphorus series, it can be bis(benzoylphenyl)phosphine oxide, benzoyldiphenylphosphine oxide or their mixture.

[0077] As the above-mentioned oxime-based compounds, they can be 2-(o-benzoyl oxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione and 1-(o-acetyl oxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone or a mixture thereof.

[0078] Based on the total weight of the composition, the content of the above-mentioned photopolymerization initiator is preferably 0.1 to 10% by weight. This is because when the photopolymerization initiator 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.

[0079] 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.

[0080] The composition for sealing an organic light-emitting element of the present invention has a low dielectric constant characteristic with a dielectric constant of 2.65 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.

[0081] 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.

[0082] 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.

[0083] 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 disclosed sealing portion 300 is a multilayer composed of a first sealing layer 310 and a second sealing layer 320, but 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.

[0084] 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.

[0085] The above sealing composition (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.

[0086] 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.

[0087] [Examples]

[0088] Compositions for sealing organic light-emitting elements of Examples 1 to 4 and Comparative Examples 1 to 5 were manufactured by mixing according to the weight ratios of photocurable monomers and photoinitiator (BAPO) described in Table 1 below.

[0089] Then, the compositions manufactured above were stirred for 12 hours and filtered using a PTFE filter with a pore size of 0.45 μm.

[0090] The filtered composition for sealing an organic light-emitting element was formed to 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.

[0091] Dielectric constant: The composition for sealing an organic light-emitting element was coated on the lower electrode to a thickness of 8.0 μm or more and cured. Then, the upper electrode Ag was deposited to a thickness. The dielectric constant was calculated after measuring the fabricated test piece using E4980A from Keysight Technologies.

[0092] Viscosity: The viscosity of the liquid composition for sealing an organic light-emitting element was measured using a rotational viscometer.

[0093] As a result, the dielectric constants of the sealing films formed from the compositions for sealing organic light-emitting elements of Examples 1 to 2 of the present invention all obtained values of 2.65 F / m or less, but the dielectric constants of the sealing films formed from Comparative Examples 1 to 6 were greater than 2.65 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.

[0094] [Table 1]

[0095]

[0096] DVSO: 1,3-Divinyltetramethyldisiloxane (CAS: 2627-95-4)

[0097] DMASO: 1,3-bis(3-methacryloxypropyl)tetramethyldisiloxane (CAS: 18547-93-8)

[0098] TDMA: 1,14-Tetradecanedioldimethacrylate (CAS: 168473-14-1)

[0099] IBOMA: Isobornyl Acrylate (CAS: 5888-33-5)

[0100] ISTA: Isooctadecyl acrylate (CAS: 93841-48-6)

[0101] BAPO: Bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide (CAS: 162881-26-7)

[0102] 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.

[0103] Symbol Explanation

[0104] 100: Substrate

[0105] 200: Organic light-emitting element

[0106] 300: Sealing portion

[0107] 310: First sealing portion

[0108] 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 2.65 or less at a frequency in the range of 100 kHz to 1 MHz. The photocurable monomer simultaneously contains (meth)acrylates represented by the following Chemical Formulas 1 to 4: [Chemical Formula 1] [Chemical Formula 2] [Chemical Formula 3] R3-L1-R4 [Chemical Formula 4] In Chemical Formulas 1 to 4, R1 to R3 are each independently a (meth)acryloyl group, R4 is a substituted or unsubstituted C 6-12 bridged cycloalkyl group, R5 is a vinyl group or a (meth)acryloyl group, L is a single bond or an alkylene group, n is from 14 to 18, m is from 5 to 15, p is from 0 to 10.

2. The organic light-emitting element sealing composition according to claim 1, wherein the viscosity of the organic light-emitting element sealing composition is 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 20 to 99% by weight.

4. The organic light-emitting element sealing composition according to claim 1, wherein the (meth)acrylate 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 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 organic light-emitting element sealing composition according to claim 1, wherein the (meth)acrylate 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 monomer represented by Chemical Formula 4 is the monomer represented by the following Chemical Formula 5 or Chemical Formula 6. [Chemical Formula 5] [Chemical Formula 6] 8. 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.

9. 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 0.1 to 10% by weight.

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 a surfactant, a curing accelerator, and an antioxidant.

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

Images