Composition for sealing organic light-emitting elements and organic light-emitting display device

Abstract

To provide a composition for sealing organic light-emitting elements, and an organic light-emitting display device including an organic layer formed by the composition for sealing organic light-emitting elements.SOLUTION: A composition for sealing organic light-emitting elements includes: a curable component containing an aliphatic difunctional photocurable monomer, an aromatic monofunctional photocurable monomer, an aliphatic monofunctional photocurable monomer, and an aromatic difunctional photocurable monomer; and a photoinitiator, the R-parameter being within the range of 0.1 to 0.17. The total content of the aliphatic difunctional photocurable monomer, the aromatic monofunctional photocurable monomer, the aliphatic monofunctional photocurable monomer, and the aromatic difunctional photocurable monomer in the composition for sealing organic light-emitting elements may be at least 95 wt% or more in the curable component.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] One embodiment of the present invention relates to a composition for sealing an organic light-emitting element and an organic light-emitting element display device. [Background technology]

[0002] Organic light-emitting devices are easily damaged and may lose their functionality and reliability when exposed to external moisture, oxygen, etc. Therefore, the organic light-emitting device needs to be sealed with a sealing layer including an organic layer and an inorganic layer formed from a sealing composition for an organic light-emitting device.

[0003] The encapsulating layer may have a structure in which organic layers and inorganic layers are alternately formed. For example, in an organic light-emitting device, organic layers and inorganic layers are alternately formed, such as an organic layer-inorganic layer-organic layer-inorganic layer, to form the encapsulating layer. Unlike the organic layer, the inorganic layer may be formed of an inorganic material. Generally, the inorganic layer may be formed by a plasma process or a vacuum process, such as sputtering, chemical vapor deposition, plasma-enhanced chemical vapor deposition, evaporation, sublimation, electron cyclotron resonance-plasma vapor deposition, or a combination thereof.

[0004] The background art of the present invention is described in Korean Patent Publication No. 10-2016-0150255, etc. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Korean Patent Publication No. 10-2016-0150255 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of an embodiment of the present invention is to provide a composition for sealing an organic light-emitting element that forms an organic layer having a low dielectric constant.

[0007] One object of an embodiment of the present invention is to provide a composition for sealing an organic light-emitting element, which forms an organic layer having excellent processability and reliability by minimizing the occurrence of wrinkles when inorganic layers are repeatedly formed.

[0008] An object of an embodiment of the present invention is to provide a composition for sealing an organic light-emitting element that has excellent inkjet jetting properties. [Means for solving the problem]

[0009] One embodiment of the present invention is a composition for sealing an organic light-emitting device.

[0010] The composition for sealing an organic light-emitting device includes curable components including an aliphatic bifunctional photocurable monomer, an aromatic monofunctional photocurable monomer, an aliphatic monofunctional photocurable monomer, and an aromatic bifunctional photocurable monomer, as well as a photoinitiator, and the composition for sealing an organic light-emitting device has an R-parameter of 0.1 to 0.17.

[0011] One embodiment of the present invention is a cured film for sealing an organic light-emitting element.

[0012] The cured film for sealing an organic light-emitting device has a dielectric constant of 2.8 or less and a glass transition temperature of 30°C to 120°C.

[0013] Another embodiment of the present invention is an organic light-emitting element display device.

[0014] The organic light-emitting element display device includes an organic layer containing a cured product of the composition for sealing the organic light-emitting element. [Effects of the Invention]

[0015] It is possible to provide a composition for sealing an organic light-emitting element that forms an organic layer having a low dielectric constant.

[0016] By minimizing the occurrence of wrinkles when inorganic layers are repeatedly formed, it is possible to provide a composition for sealing an organic light-emitting device that forms an organic layer with excellent processability and reliability.

[0017] It is possible to provide a composition for sealing an organic light-emitting element that has excellent inkjet jetting properties. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a cross-sectional view of an organic light emitting display device according to an embodiment of the present invention; [Figure 2] 1 is a cross-sectional view of an organic light emitting display device according to another embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0019] The present invention will be described in detail with reference to the accompanying drawings, by way of embodiments, so that those skilled in the art can easily implement the present invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein. To clearly explain the present invention in the drawings, parts that are not relevant to the description are omitted, and the same or similar components are designated by the same reference numerals throughout the specification. The length and size of each component in the drawings are set for the convenience of explaining the present invention, and the present invention is not limited to the length and size of each component shown in the drawings.

[0020] In this specification, "(meth)acrylic" means acrylic and / or methacrylic.

[0021] In this specification, unless otherwise defined, the term "substituted" means that one or more hydrogen atoms of the functional group of the present invention are substituted with a halogen (F, Cl, Br, or I), a hydroxy group, a nitro group, a cyano group, an imino group (=NH, =NR, where R is an alkyl group having 1 to 10 carbon atoms), an amino group (-NH, -NH(R'), -N(R"(R"'), where R', R", and R"' are each independently an alkyl group having 1 to 10 carbon atoms), an amidino group, a hydrazine or hydrazone group, a carboxy group, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, a heteroaryl group having 3 to 30 carbon atoms, or a heterocycloalkyl group having 2 to 30 carbon atoms.

[0022] In the general formulas described herein, unless otherwise specified, it can be assumed that hydrogen is bonded in the structure of the general formula.

[0023] The terms used herein are merely used to describe exemplary embodiments and are not intended to limit the present invention. The singular expressions include the plural expressions unless otherwise clearly indicated in the context.

[0024] When describing a range of values ​​in this specification, "X to Y" means at least X and at most Y.

[0025] The composition for sealing an organic light-emitting device (hereinafter referred to as the composition) according to one embodiment can form an organic layer having a significantly low dielectric constant over a wide frequency range after curing. Here, the "organic layer" can also be said to be a cured film for sealing an organic light-emitting device.

[0026] In one embodiment, the frequency range may be 100 kHz to 1000 kHz. The organic layer may have a dielectric constant of 2.8 or less, for example, 2.0 to 2.8, over a wide frequency range. When the dielectric constant of the organic layer is in the above range, the organic light-emitting device is not affected by external static electricity or electricity, and its performance is fully exhibited.

[0027] The composition can form an organic layer with excellent processability and reliability. In this regard, the composition may have a glass transition temperature of 30°C to 120°C or 40°C to 120°C after curing. By exhibiting a glass transition temperature within this range, the strength of the organic layer can be ensured and the occurrence of wrinkles during inorganic deposition can be minimized. For example, the composition may have a glass transition temperature of 40°C to 60°C after curing. By exhibiting a glass transition temperature within this range, the strength of the organic layer can be ensured and the occurrence of wrinkles during inorganic deposition can be minimized even if the organic layer does not have a high dielectric constant.

[0028] After curing, the composition can form an organic layer having a modulus of 0.8 GPa or more, for example, 0.8 GPa to 5 GPa. By exhibiting a modulus in this range, the strength of the organic layer can be ensured and the occurrence of wrinkles during inorganic vapor deposition can be minimized.

[0029] After curing, the composition has a moisture permeability of 1 g / m 2 day or less, e.g. 0g / m 2 day~1g / m 2 By exhibiting a moisture permeability in the above range, the reliability of the light-emitting device can be increased.

[0030] The composition has excellent inkjet printability and can form a uniform organic layer. In this regard, the composition may have a viscosity of 7 cP to 100 cP, for example, 7 cP to 60 cP, or 7 cP to 50 cP, at 25±2°C (23°C to 27°C). By having a viscosity in the above range, the inkjet printability of the sealing composition can be easily improved.

[0031] A composition according to one embodiment includes curable components including an aliphatic difunctional photocurable monomer, an aromatic monofunctional photocurable monomer, an aliphatic monofunctional photocurable monomer, and an aromatic difunctional photocurable monomer, as well as a photoinitiator, and the composition for sealing an organic light-emitting device has an R-parameter of 0.1 to 0.17.

[0032] First, the R-parameter will be explained.

[0033] The R-parameter is a criterion for determining whether an organic layer formed from a composition containing an aliphatic difunctional photocurable monomer, an aromatic monofunctional photocurable monomer, an aliphatic monofunctional photocurable monomer, and an aromatic difunctional photocurable monomer as curable components satisfies the required dielectric constant and glass transition temperature. Even if the composition contains an aliphatic difunctional photocurable monomer, an aromatic monofunctional photocurable monomer, an aliphatic monofunctional photocurable monomer, and an aromatic difunctional photocurable monomer as curable components, if the composition does not satisfy the R-parameter of 0.1 to 0.17, it may be difficult for the organic layer to achieve a dielectric constant of 2.8 or less, making it difficult to achieve plasma resistance. "Plasma resistance" is evaluated by the plasma etching rate, which can be measured using conventional methods known to those skilled in the art. For example, the R-parameter may be 0.1 to 0.165.

[0034] An R-parameter of 0.1 to 0.17 can be achieved by adjusting the content of each of the aliphatic difunctional photocurable monomer, aromatic monofunctional photocurable monomer, aliphatic monofunctional photocurable monomer, and aromatic difunctional photocurable monomer, as well as the type of each component.

[0035] The R-parameter can be calculated using the following formula:

[0036] To calculate the R-parameter, the photocurable monomers contained in the composition are numbered in order from 1 to n, where n is a natural number equal to or greater than 4. The R-parameter is the sum of the values ​​calculated for each photocurable monomer according to the following Equation 1:

[0037] Formula 1 [(number of carbon atoms constituting the benzene ring in the molecule of the nth photocurable monomer × atomic mass of one carbon) / (weight average molecular weight of the nth photocurable monomer)] × (weight ratio of the nth photocurable monomer)

[0038] In Formula 1, "the number of carbon atoms constituting the benzene ring" means the number of carbon atoms constituting the benzene ring in the molecular structure. For example, a phenyl group has 6 carbon atoms, and naphthalene has 10 carbon atoms. If there are two or more benzene rings in the molecular structure, the numbers of carbon atoms constituting each benzene ring are added together.

[0039] In Equation 1, the "weight average molecular weight" is the commonly known Mw, which is a value determined in terms of polystyrene using, for example, gel permeation chromatography.

[0040] In Formula 1, the "weight ratio" is the ratio of the content of the nth photocurable monomer to the total amount of photocurable monomers contained in the composition, based on weight.

[0041] Each component in the composition will be described in detail below.

[0042] Curing component The curable component includes an aliphatic difunctional photocurable monomer, an aromatic monofunctional photocurable monomer, an aliphatic monofunctional photocurable monomer, and an aromatic difunctional photocurable monomer. The curable component is a photocurable component, meaning a component that can be cured by light.

[0043] According to one embodiment, the total amount of the aliphatic difunctional photocurable monomer, aromatic monofunctional photocurable monomer, aliphatic monofunctional photocurable monomer, and aromatic difunctional photocurable monomer may be 95% by weight or more, for example, 99% to 100% by weight, of the curable components. By adopting the above range, unnecessary monomers are not contained, and the effects of the composition described above can be fully exhibited.

[0044] The total amount of the aliphatic difunctional photocurable monomer and the aliphatic monofunctional photocurable monomer in the composition may be 50 to 90 parts by weight, for example, 55 to 80 parts by weight, per 100 parts by weight of the composition. By adopting this range, the dielectric constant of the organic layer can be reduced.

[0045] In the composition, the total amount of the aromatic monofunctional photocurable monomer and the aromatic difunctional photocurable monomer may be 10 to 50 parts by weight, for example, 20 to 45 parts by weight, per 100 parts by weight of the composition. By adopting this range, the processability and reliability of the organic layer can be easily improved.

[0046] Aliphatic bifunctional photocurable monomer The aliphatic bifunctional photocurable monomer contributes to reducing the dielectric constant of the organic layer.

[0047] The aliphatic bifunctional photocurable monomer can be represented by the following general formula 1. General formula 1

[0048] [ka]

[0049] In general formula 1, R 1 ,R 2 are each independently hydrogen or an alkyl group having 1 to 5 carbon atoms, L 11 is a substituted or unsubstituted, straight-chain or branched-chain alkylene group having 8 to 20 carbon atoms.

[0050] In General Formula 1, the "number of carbon atoms" means the number of carbon atoms in the main chain, and does not include the number of carbon atoms in the side chain.

[0051] In one embodiment, in general formula 1, L 11 may be a substituted or unsubstituted, linear or branched alkylene group having 10 to 16 or 12 to 14 carbon atoms. 11 may be an unsubstituted linear alkylene group having 10 to 16 or 12 to 14 carbon atoms.

[0052] For example, L 11 is -(CH2) 10 -,-(CH2) 11 -,-(CH2)12 -,-(CH2) 13 -,-(CH2) 14 -,-(CH2) 15 -,-(CH2) 16 -,-(CH2) 17 -,-(CH2) 18 -,-(CH2) 19 -,-(CH2) 20 For example, the monomer of general formula 1 may include one or more of 1,8-octanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,11-undecanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, and 1,14-tetradecanediol di(meth)acrylate.

[0053] The aliphatic bifunctional photocurable monomer may be contained in an amount of 20 to 60 parts by weight, for example, 30 to 50 parts by weight, per 100 parts by weight of the composition. By adopting this range, the dielectric constant of the organic layer can be reduced, and the processability and reliability of the organic layer can be prevented from being adversely affected.

[0054] Aromatic monofunctional photocurable monomer Aromatic monofunctional photocurable monomers can improve the reliability and processability of organic layers. Aliphatic difunctional photocurable monomers and aliphatic monofunctional photocurable monomers can reduce the dielectric constant of organic layers formed from the compositions, but can also reduce the reliability and processability of the organic layers. In this regard, aromatic monofunctional photocurable monomers can contribute to improving the processability and reliability of organic layers by adjusting the modulus and glass transition temperature of the organic layers.

[0055] The aromatic monofunctional photocurable monomer can be represented by the following general formula 2. General formula 2 (CH2=)-C(R 3 )-C(=O)-O-(-CH2-)sL 21

[0056] In general formula 2, R 3 is hydrogen or an alkyl group having 1 to 5 carbon atoms, and s is an integer of 0 to 10, L 21 is a substituted or unsubstituted C6 to C50 aryl group, or a substituted or unsubstituted C6 to C50 aryloxy group.

[0057] For example, L 21 is a phenylphenoxyethyl group, a phenoxyethyl group, a benzyl group, a phenyl group, a phenylphenoxy group, a phenoxy group, a phenylethyl group, a phenylpropyl group, a phenylbutyl group, a methylphenylethyl group, a propylphenylethyl group, a methoxyphenylethyl group, a cyclohexylphenylethyl group, a chlorophenylethyl group, a bromophenylethyl group, a methylphenyl group, a methylethylphenyl group, a methoxyphenyl group, a propylphenyl group, a cyclohexylphenyl group, a chlorophenyl group, a bromophenyl group, a phenylphenyl group, a biphenyl group, a terphenyl group, a quaterphenyl group, l) group, anthracenyl group, naphthalenyl group, triphenylenyl group, methylphenoxy group, ethylphenoxy group, methylethylphenoxy group, methoxyphenyloxy group, propylphenoxy group, cyclohexylphenoxy group, chlorophenoxy group, bromophenoxy group, biphenyloxy group, terphenyloxy group, quaterphenyloxy group, anthracenyloxy group, naphthalenyloxy group, and triphenylenyloxy group.

[0058] Specifically, the aromatic photocurable monomers include 2-phenylphenoxyethyl (meth)acrylate, naphthyl (meth)acrylate, naphthalenylmethyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenyl (meth)acrylate, phenoxy (meth)acrylate, 2-ethylphenoxy (meth)acrylate, benzyl (meth)acrylate, 2-phenylethyl (meth)acrylate, 3-phenylpropyl (meth)acrylate, 4-phenylbutyl (meth)acrylate, 2-(2-methylphenyl)ethyl (meth)acrylate, acrylate, 2-(3-methylphenyl)ethyl (meth)acrylate, 2-(4-methylphenyl)ethyl (meth)acrylate, 2-(4-propylphenyl)ethyl (meth)acrylate, 2-(4-(1-methylethyl)phenyl)ethyl (meth)acrylate, 2-(4-methoxyphenyl)ethyl (meth)acrylate, 2-(4-cyclohexylphenyl)ethyl (meth)acrylate, 2-(2-chlorophenyl)ethyl (meth)acrylate, 2-(3-chlorophenyl)ethyl (meth)acrylate, 2-(4-chlorophenyl)ethyl (meth)acrylate, 2-(4-bromophenyl)ethyl (meth)acrylate, 2-(3-phenylphenyl)ethyl (meth)acrylate, 4-(biphenyl-2-yloxy)butyl (meth)acrylate, 3-(biphenyl-2-yloxy)butyl (meth)acrylate, 2-(biphenyl-2-yloxy)butyl (meth)acrylate, 1-(biphenyl-2-yloxy)butyl (meth)acrylate, 4-(biphenyl-2-yloxy)propyl (meth)acrylate, 3-(biphenyl-2-yloxy)propyl (meth)acrylate Acrylate, 2-(biphenyl-2-yloxy)propyl (meth)acrylate, 1-(biphenyl-2-yloxy)propyl (meth)acrylate, 4-(biphenyl-2-yloxy)ethyl (meth)acrylate, 3-(biphenyl-2-yloxy)ethyl (meth)acrylate, 2-(biphenyl-2-yloxy)ethyl (meth)acrylate, 1-(biphenyl-2-yloxy)ethyl (meth)acrylate, 2-(4-benzylphenyl)ethyl (meth)acrylate, 1-(4-benzylphenyl)ethyl (meth)acrylate,Alternatively, the aromatic photocurable monomer may include one or more of these structural isomers, but is not limited thereto. In other words, the (meth)acrylates mentioned in the present invention are only examples and are not limited thereto. Furthermore, the aromatic photocurable monomer includes all acrylates that are structural isomers. For example, even if only 2-phenylethyl (meth)acrylate is mentioned as an example of the aromatic photocurable monomer of the present invention, the aromatic photocurable monomer includes all isomers including 3-phenylethyl (meth)acrylate and 4-phenyl (meth)acrylate.

[0059] Preferably, the aromatic monofunctional photocurable monomer is represented by the general formula 2, L 21 is a phenylphenoxyethyl group or a biphenylyl group.

[0060] The aromatic monofunctional photocurable monomer may be contained in an amount of 5 to 30 parts by weight, for example, 10 to 30 parts by weight, per 100 parts by weight of the composition. By adopting this range, the dielectric constant of the organic layer can be reduced, and reliability and processability can be improved.

[0061] Aliphatic monofunctional photocurable monomer The composition is an aliphatic photocurable monomer, and further contains an aliphatic monofunctional photocurable monomer in addition to the aliphatic difunctional photocurable monomer.

[0062] Both aliphatic difunctional photocurable monomers and aliphatic monofunctional photocurable monomers can reduce the dielectric constant of an organic layer. However, a composition containing only an aliphatic difunctional photocurable monomer without an aliphatic monofunctional photocurable monomer may have limitations in reducing the dielectric constant of the organic layer. Furthermore, a composition containing only an aliphatic monofunctional photocurable monomer without an aliphatic difunctional photocurable monomer may result in insufficient curing of the composition, resulting in insufficient formation of an organic layer.

[0063] In this regard, the aliphatic difunctional photocurable monomer:aliphatic monofunctional photocurable monomer may be contained in the composition in a weight ratio of 30-70:30-70, for example 40-70:30-60, per 100 parts by weight in total. By adopting the above range, it is possible to achieve the effects of lowering the dielectric constant and improving the photocuring rate.

[0064] The aliphatic monofunctional photocurable monomer can be represented by the following general formula 3. General formula 3

[0065] [ka]

[0066] In general formula 3, R 4 are each independently hydrogen or an alkyl group having 1 to 5 carbon atoms, L 31 is a substituted or unsubstituted, straight-chain or branched-chain alkyl group having 8 to 20 carbon atoms.

[0067] In general formula 3, the "number of carbon atoms" means the number of carbon atoms in the main chain, and does not include the number of carbon atoms in the side chain.

[0068] In one embodiment, in general formula 3, L 31 may be a substituted or unsubstituted, straight-chain or branched-chain alkyl group having 10 to 20 or 10 to 18 carbon atoms.

[0069] For example, in general formula 3, L 31 may be an unsubstituted, straight-chain alkyl group having 10 to 20 or 10 to 18 carbon atoms.

[0070] For example, the monomer of general formula 3 may include one or more of octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, tetradecyl (meth)acrylate including 2-decyl 1-tetradecanyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, cetyl (meth)acrylate, etc. Preferably, the monomer of general formula 3 may include one or more of stearyl (meth)acrylate, 2-decyl 1-tetradecanyl (meth)acrylate.

[0071] The aliphatic monofunctional photocurable monomer may be contained in an amount of 10 to 50 parts by weight, for example, 20 to 40 parts by weight, per 100 parts by weight of the composition. By adopting this range, the dielectric constant of the organic layer can be reduced, and reliability and processability can be improved.

[0072] Aromatic bifunctional photocurable monomer The composition further contains, as the aromatic photocurable monomer, an aromatic difunctional photocurable monomer in addition to the aromatic monofunctional photocurable monomer.

[0073] Both aromatic monofunctional photocurable monomers and aromatic difunctional photocurable monomers can improve the processability and reliability of organic layers. However, compositions containing only aromatic difunctional photocurable monomers, but not aromatic monofunctional photocurable monomers, may have limitations in reducing the dielectric constant of the organic layer. Furthermore, compositions containing only aromatic monofunctional photocurable monomers, but not aromatic difunctional photocurable monomers, may result in insufficient curing of the composition, resulting in inadequate formation of the organic layer.

[0074] In this regard, the aromatic monofunctional photocurable monomer:aromatic difunctional photocurable monomer may be contained in the composition in a weight ratio of 20-90:10-80, for example 30-90:10-70, per 100 parts by weight in total. By adopting the above range, it is possible to achieve the effects of lowering the dielectric constant and improving the photocuring rate.

[0075] The aromatic bifunctional photocurable monomer can be represented by the following general formula 4. General formula 4

[0076] [ka]

[0077] In general formula 4, R 5 ,R 6 are each independently hydrogen or an alkyl group having 1 to 5 carbon atoms, L 41 ,L 43 is a substituted or unsubstituted arylene group having 6 to 20 carbon atoms, L 42 is a single bond or a linear or branched alkylene group having 1 to 20 carbon atoms.

[0078] In one embodiment, in general formula 4, L 42 is a single bond or a linear or branched alkylene group having 1 to 10 carbon atoms, for example, L 42 may be a linear or branched, substituted or unsubstituted alkylene group having 1 to 5 carbon atoms.

[0079] For example, the monomer of general formula 4 can include one or more of bisphenol A di(meth)acrylate, phenol 4,4-methylene dimethacrylate.

[0080] The aromatic bifunctional photocurable monomer may be contained in an amount of 1 part by weight to 30 parts by weight, for example, 1 part by weight to 20 parts by weight, per 100 parts by weight of the composition. By adopting this range, the dielectric constant of the organic layer can be reduced, and reliability and processability can be improved.

[0081] Photoinitiator The photoinitiator may include, without limitation, a conventional photopolymerization initiator capable of causing a photocuring reaction, such as a triazine-based, acetophenone-based, benzophenone-based, thioxanthone-based, benzoin-based, phosphorus-based, oxime-based, or a mixture thereof.

[0082] Preferably, the photoinitiator may include a phosphorus-based initiator having a maximum absorption wavelength of 360 nm to 400 nm. When a phosphorus-based initiator is used, curing of the composition of the present invention can be initiated more quickly with long-wavelength UV (e.g., 300 nm to 400 nm). The phosphorus-based initiator may be diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphinate, or a mixture thereof. For example, one or more photoinitiators may be used. The "maximum absorption wavelength" may be a value measured by a conventional method known to those skilled in the art or may be a value obtained from a product catalog.

[0083] The photoinitiator can be contained in an amount of 1 to 10 parts by weight, for example, 1 to 5 parts by weight, per 100 parts by weight of the composition. By adopting this range, the photocuring rate of the composition can be improved and a decrease in light transmittance due to photoinitiator residue can be prevented.

[0084] The composition can be formed by mixing the curable component and the photoinitiator. For example, the composition of the present invention can be formed as a solvent-free type that does not contain a solvent.

[0085] The composition is a photocurable composition, and the light intensity is 10 mW / cm 2 ~500mW / cm 2 The sealing layer can be formed by photo-curing the resin by irradiating it with UV light of this wavelength for 1 to 50 seconds.

[0086] The composition may further contain conventional additives known to those skilled in the art, including, but not limited to, heat stabilizers, antioxidants, UV absorbers, etc.

[0087] The composition may have a viscosity of 7 cps to 100 cps, preferably 7 cps to 60 cps, and more preferably 7 cps to 50 cps at 25±2° C. (23° C. to 27° C.) By adopting the above range, the sealing composition can have excellent ink-jetting properties.

[0088] The photocuring rate of the composition may be 89% to 100%, preferably 91% to 99%, and more preferably 91% to 93%. By adopting the above range, the cured product of the composition can function as an organic layer. The photocuring rate can be measured by the following method.

[0089] *Method for measuring photocuring rate The sealing composition was measured using FT-IR (NICOLET 4700, Thermo) at 1635 cm -1 Near (C=C), 1720cm -1 The intensity of the absorption peak near (C=O) is measured. The sealing composition is sprayed onto a glass substrate, and the absorption peak intensity is measured at 4000 mJ / cm at an oxygen concentration of 5 ppm or less. 2 The resin is cured by irradiating it with UV light (wavelength: 395 nm) at 1635 cm to obtain a film measuring 20 cm x 20 cm x 3 μm (width x length x thickness). -1 Near (C=C), 1720cm -1 The intensity of the absorption peak of the cured film near (C=O) is measured. The photocuring rate is calculated using the following equation 2:

[0090] Formula 2 Photocuring rate (%)=|1-(A / B)|×100

[0091] In Equation 2, A is the 1720 cm -1 Intensity of the absorption peak near 1635 cm -1B is the ratio of the intensities of the absorption peaks in the vicinity of 1720 cm -1 Intensity of the absorption peak near 1635 cm -1 is the ratio of the intensities of the absorption peaks in the vicinity

[0092] The composition can be used to encapsulate an organic light-emitting device. Specifically, the composition can form an organic layer in an encapsulation structure in which an inorganic layer and an organic layer are formed in this order.

[0093] The composition can also be used to seal device components, particularly display device components, that may decompose or fail due to permeation of gases or liquids in the surrounding environment, such as atmospheric oxygen and / or moisture and / or water vapor, or permeation of chemicals used in processing electronic products. For example, the device components can seal lighting devices, metal sensor pads, microdisk lasers, electrochromic devices, photochromic devices, microelectromechanical systems, solar cells, integrated circuits, charge-coupled devices, light-emitting polymers, etc., but the devices to be sealed are not limited to these.

[0094] Another embodiment of the present invention is a cured film for sealing an organic light-emitting element.

[0095] The cured film for sealing an organic light-emitting device has a dielectric constant of 2.8 or less and a glass transition temperature of 30° C. to 120° C. This has already been explained, so a detailed description will be omitted.

[0096] The cured film may contain a cured product of the above-described composition for sealing an organic light-emitting device.

[0097] Another embodiment of the present invention is an organic light emitting device display device.

[0098] The organic light emitting device display device may include an organic layer formed using the composition for sealing an organic light emitting device according to one embodiment of the present invention. Specifically, the organic light emitting device display device includes an organic light emitting device and a barrier stack formed on the organic light emitting device, the barrier stack including an inorganic layer and an organic layer, and the organic layer may be formed using the composition for sealing an organic light emitting device according to one embodiment of the present invention. As a result, the reliability of the organic light emitting device display device may be improved.

[0099] Hereinafter, an organic light emitting diode display device according to an embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a cross-sectional view of an organic light emitting diode display device according to an embodiment of the present invention.

[0100] 1, an organic light emitting device display 100 includes a substrate 10, an organic light emitting device 20 formed on the substrate 10, and a barrier stack 30 formed on the organic light emitting device 20 and including an inorganic layer 31 and an organic layer 32. The inorganic layer 31 contacts the organic light emitting device 20, and the organic layer 32 may be formed using a composition for sealing an organic light emitting device according to an embodiment of the present invention.

[0101] The substrate 10 is not particularly limited as long as it is a substrate on which an organic light emitting device can be formed, and may be made of materials such as transparent glass, a plastic sheet, silicon, or a metal substrate.

[0102] The organic light emitting element 20 is a type commonly used in organic light emitting element display devices, and although not shown in FIG. 1, it includes a first electrode, a second electrode, and an organic light emitting film formed between the first and second electrodes. The organic light emitting film may be formed by sequentially stacking a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer, but is not limited thereto.

[0103] The barrier stack 30 includes an organic layer and an inorganic layer, and the organic layer and the inorganic layer are different in the components constituting each layer, and each layer can perform the function of sealing the organic light emitting device.

[0104] The inorganic layer can complement the effects of the organic layer by having different components. For example, the inorganic layer can be a metal, a nonmetal, an intermetallic compound or alloy, a non-intermetallic compound or alloy, a metal or nonmetal oxide, a metal or nonmetal fluoride, a metal or nonmetal nitride, a metal or nonmetal carbide, a metal or nonmetal oxynitride, a metal or nonmetal boride, a metal or nonmetal oxyboride, a metal or nonmetal silicide, or a mixture thereof. The metal or nonmetal can be, but is not limited to, silicon (Si), aluminum (Al), selenium (Se), zinc (Zn), antimony (Sb), indium (In), germanium (Ge), tin (Sn), bismuth (Bi), a transition metal, a lanthanum group metal, etc. Specifically, the inorganic layer may be silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy), ZnSe, ZnO, Sb2O3, AlOx, including Al2O3, In2O3, SnO2.

[0105] The inorganic layer can be deposited by plasma or vacuum processes such as sputtering, chemical vapor deposition, plasma enhanced chemical vapor deposition, evaporation, sublimation, electron cyclotron resonance-plasma vapor deposition and combinations thereof.

[0106] When organic layers are deposited alternately with inorganic layers, they can ensure the smoothing properties of the inorganic layers and prevent defects in one inorganic layer from propagating to another inorganic layer.

[0107] The organic layer can be formed by a combination of coating, vapor deposition, curing, etc. of the composition for sealing an organic light-emitting element according to an embodiment of the present invention. For example, the composition for sealing an organic light-emitting element can be coated to a thickness of 1 μm to 50 μm, and the applied light intensity can be 10 mW / cm 2 ~500mW / cm 2 It can be hardened by irradiating it with light for 1 to 50 seconds.

[0108] The barrier stack includes organic and inorganic layers, but the total number of organic and inorganic layers is not limited. The total number of organic and inorganic layers can be varied depending on the level of permeation resistance to oxygen, moisture, water vapor, and / or chemicals. For example, the total number of organic and inorganic layers may be 10 or less, for example, 2 to 7 layers, and specifically, the barrier stack may be formed in the order inorganic layer / organic layer / inorganic layer / organic layer / inorganic layer / organic layer / inorganic layer, for a total of 7 layers.

[0109] In the barrier stack, organic and inorganic layers can be deposited alternately. This structure ensures that the organic layer formed by the above-mentioned composition exhibits the above-mentioned desirable properties. In this way, the organic and inorganic layers can complement or enhance the sealing effect of the device.

[0110] Hereinafter, an organic light emitting diode display device according to another embodiment of the present invention will be described with reference to Fig. 2. Fig. 2 is a cross-sectional view of an organic light emitting diode display device according to another embodiment of the present invention.

[0111] 2, an organic light emitting device display 200 includes a substrate 10, an organic light emitting device 20 formed on the substrate 10, and a barrier stack 30 formed on the organic light emitting device 20 and including an inorganic layer 31 and an organic layer 32. The inorganic layer 31 seals an internal space 40 in which the organic light emitting device 20 is housed, and the organic layer 32 may be formed using a composition for sealing an organic light emitting device according to an embodiment of the present invention. The organic light emitting device display 200 is substantially the same as the organic light emitting device display 200 according to an embodiment of the present invention, except that the inorganic layer does not contact the organic light emitting device. [Example]

[0112] The present invention will be described in more detail with reference to preferred embodiments thereof below, which are merely examples of the present invention and should not be construed as limiting the present invention in any way.

[0113] The specific specifications of the components used in the examples and comparative examples are as follows:

[0114] (A) Aliphatic bifunctional photocurable monomer (A1) 1,12-dodecanediol dimethacrylate (SARTOMER) (A2) 1,14-tetradecanediol dimethacrylate (Miwon Trading Company) (A3) Triethylene glycol dimethacrylate (Aldrich)

[0115] (B) Aromatic monofunctional photocurable monomer (B1) o-Phenylphenoxyethyl acrylate (green chemical) (B2) 4-biphenylyl methacrylate (green chemical) (B3) 2-phenyl-2-(phenylthio)ethyl 2-propenoate (a compound represented by the following general formula, produced using benzenethiol, zinc perchlorate, styrene oxide, and acryloyl chloride)

[0116] [ka]

[0117] (C) Aliphatic monofunctional photocurable monomer (C1) Stearyl methacrylate (green chemical) (C2) 2-Decyl-1-tetradecanyl methacrylate (Kyoeisha) (C3) 2-(dimethylamino)ethyl acrylate (Aldrich)

[0118] (D) Aromatic bifunctional photocurable monomer (D1) Bisphenol A dimethacrylate (TCI) (D2) Phenol, 4,4-methylenedimethacrylate (CHEMIELIVA, compound of the following structure)

[0119] [ka]

[0120] (D3) 1,1'-[[1,1'-biphenyl]-2,2'-diylbis(oxy-2,1-ethanediyl)]di-2-propenoate (compound represented by the following general formula, prepared using 2-hydroxyethyl acrylate and p-toluenesulfonyl chloride)

[0121] [ka]

[0122] (E) Photoinitiator (phosphorus-based initiator, Darocur TPO, BASF)

[0123] Example 1 50 parts by weight of (A2), 20 parts by weight of (B2), 24 parts by weight of (C2), 3 parts by weight of (D1), and 3 parts by weight of (E) were placed in a 125 ml brown polypropylene bottle and mixed using a shaker at room temperature for 3 hours to prepare a sealing composition.

[0124] Examples 2 to 4 and Comparative Examples 1 to 6

[0125] The sealing composition was prepared in the same manner as in Example 1, except that the content of each component was changed as shown in Table 1 below (unit: parts by weight).

[0126] In Table 1 below, "-" means that the corresponding ingredient is not contained.

[0127] The following physical properties were measured for the compositions prepared in the examples and comparative examples, and the results are shown in Table 1.

[0128] (1) Dielectric constant (no unit): The sealing compositions of the examples and comparative examples were applied to a chromium (Cr) plate to a predetermined thickness, and the dielectric constant was 4000 mJ / cm at an oxygen concentration of 5 ppm or less. 2The coating was photocured by UV irradiation (wavelength 395 nm) at 1000 K, forming a coating film with a thickness of 8 μm. After vapor deposition of aluminum (electrode for measuring the dielectric constant) on the coating film, the dielectric constant was measured using an impedance measuring instrument (E4990A, Impedance Analyzer) at a frequency of 200 kHz and a temperature of 25°C.

[0129] (2) Modulus of organic layer (unit: GPa): The sealing compositions of the examples and comparative examples were applied to a glass plate in a predetermined thickness, and the modulus was 4000 mJ / cm at an oxygen concentration of 5 ppm or less. 2 An 8 μm-thick organic layer was prepared by photo-curing with UV irradiation (wavelength 395 nm) at 25°C, and a specimen for modulus measurement was prepared. The modulus of the specimen was measured using a Nano Indentor G200 (Agilent). The modulus was measured at 25°C under the following conditions: Experimental mode: Indentation Mode (using Berkovitz), Control mode: Force control, Maximum force: 60 μN (0213-TJ: 54 μN with 100 nm displacement control). The specimen was loaded with the nano indenter for 5 seconds, held for 2 seconds, and then unloaded for another 5 seconds.

[0130] (3) Glass transition temperature (Tg) of organic layer (unit: °C): The sealing compositions of the examples and comparative examples were applied to a silicon wafer in a predetermined thickness, and the glass transition temperature was 4000 mJ / cm at an oxygen concentration of 5 ppm or less. 2 The organic layer was cured by photocuring with UV irradiation (wavelength 395 nm) at 1000 kJ / cm2, forming a cured coating film. The coating film was separated and the glass transition temperature of the cured organic layer coating film was measured using a differential scanning calorimeter manufactured by TA Instruments.

[0131] (4) Moisture transmission rate (WVTR) (unit: g / m 2 Day): Using a moisture-permeable PET film with a thickness of 80 μm as a substrate, the sealing compositions of the examples and comparative examples were applied to a predetermined thickness, and the oxygen concentration was 5 ppm or less and 4000 mJ / cm2 An 8μm thick organic layer was fabricated by photo-curing with UV irradiation (wavelength 395nm) at 4000kJ / cm2. Using the PECVD method, SiNx 0.1μm was deposited on this organic film under conditions of SiH 430sccm, N 2800sccm, plasma power 150W, and substrate temperature 100℃. The moisture permeability was then measured using a Mocon Permatran-W 700 under conditions of 100%RH, 760mmHg, and 0%RH nitrogen carrier gas until saturation time.

[0132] (5) R-parameter (unitless): The value of Equation 1 was calculated for each photocurable monomer in the composition according to the method described above, and then added together.

[0133] [Table 1]

[0134] NG: Measurement not possible because no film was formed. As shown in Table 1, the composition for sealing an organic light-emitting device of the present invention having A, B, C, and D in the amounts shown here has an R-parameter of 0.1 to 0.17, so that it has a low dielectric constant and can reduce moisture permeability without reducing the glass transition temperature and modulus, and therefore can be effective as an encapsulant.

[0135] Simple modifications or alterations of the present invention can be easily implemented by a person having ordinary skill in the art, and all such modifications and alterations can be considered to be included within the scope of the present invention.

Claims

1. the composition comprises a curable component including an aliphatic difunctional photocurable monomer, an aromatic monofunctional photocurable monomer, an aliphatic monofunctional photocurable monomer, and an aromatic difunctional photocurable monomer, and a photoinitiator; A composition for sealing an organic light-emitting element, having an R-parameter of 0.1 to 0.

17.

2. 2. The composition for sealing an organic light-emitting element according to claim 1, wherein a total amount of the aliphatic bifunctional photocurable monomer, the aromatic monofunctional photocurable monomer, the aliphatic monofunctional photocurable monomer, and the aromatic bifunctional photocurable monomer is contained in the curable components in an amount of 95% by weight or more.

3. 2. The composition for sealing an organic light-emitting element according to claim 1, wherein the aliphatic bifunctional photocurable monomer:the aliphatic monofunctional photocurable monomer is contained in a ratio of 30 to 70:30 to 70 in a total of 100 parts by weight.

4. 2. The composition for sealing an organic light-emitting element according to claim 1, wherein the aromatic monofunctional photocurable monomer:the aromatic difunctional photocurable monomer is contained in a weight ratio of 20 to 90:10 to 80 in a total of 100 parts by weight.

5. The aliphatic bifunctional photocurable monomer is represented by the following general formula 1: General formula 1 【Chemical 1】 In the general formula 1, R １ , R ２ are each independently hydrogen or an alkyl group having 1 to 5 carbon atoms, L １１ 2. The composition for sealing an organic light-emitting element according to claim 1, wherein is a substituted or unsubstituted, linear or branched alkylene group having 8 to 20 carbon atoms.

6. The aromatic bifunctional photocurable monomer is represented by the following general formula 4: General formula 4 【Chemistry 2】 In the general formula 4, R ５ , R ６ are each independently hydrogen or an alkyl group having 1 to 5 carbon atoms, L ４１ , L ４３ is a substituted or unsubstituted arylene group having 6 to 20 carbon atoms, L ４２ 2. The composition for sealing an organic light-emitting element according to claim 1, wherein is a single bond or a linear or branched alkylene group having 1 to 20 carbon atoms.

7. The aliphatic monofunctional photocurable monomer is represented by the following general formula 3: General formula 3 【Chemistry 3】 In the general formula 3, R ４ are each independently hydrogen or an alkyl group having 1 to 5 carbon atoms, L ３１ 2. The composition for sealing an organic light-emitting element according to claim 1, wherein is a substituted or unsubstituted, linear or branched alkyl group having 8 to 20 carbon atoms.

8. 20 to 60 parts by weight of the aliphatic bifunctional photocurable monomer, 5 to 30 parts by weight of the aromatic monofunctional photocurable monomer, 10 to 50 parts by weight of the aliphatic monofunctional photocurable monomer, 1 to 30 parts by weight of the aromatic bifunctional photocurable monomer, and The composition for sealing an organic light-emitting element according to claim 1, wherein the photoinitiator is contained in an amount of 1 to 10 parts by weight.

9. A cured film for sealing an organic light-emitting element, having a dielectric constant of 2.8 or less and a glass transition temperature of 30°C to 120°C.

10. The cured film for sealing an organic light-emitting element according to claim 9, comprising a cured product of the composition for sealing an organic light-emitting element according to claim 1.

11. An organic light-emitting element display device comprising an organic layer comprising a cured product of the composition for sealing an organic light-emitting element according to claim 1 .

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