Organic compound and organic light-emitting device comprising same

Abstract

The present invention relates to an organic compound employed as a material for a light efficiency improvement layer (capping layer) provided in an organic light-emitting device. When the compound according to the present invention is employed in a light efficiency improvement layer, a high-efficiency and long-lifetime organic light-emitting device having improved low-voltage driving characteristics, luminous efficiency, color purity, lifespan characteristics and the like can be implemented, and thus the present invention can be industrially useful for various lighting and display devices.

Description

Organic compounds and organic light-emitting diodes containing the same

[0001] The present invention relates to an organic compound used as a material for a capping layer for improving light efficiency in an organic light-emitting diode, and to a high-efficiency organic light-emitting diode in which device characteristics such as low-voltage driving, luminous efficiency, color purity, and lifespan are significantly improved by using the same in the capping layer.

[0002] Organic light-emitting diodes (OLEDs) can be formed on transparent substrates, and compared to plasma display panels or inorganic light-emitting diode (EL) displays, they have the advantages of being able to operate at a low voltage of 10 V or less, consuming relatively little power, and having excellent color quality, and can display three colors of green, blue, and red, so they have recently become the subject of much interest as next-generation display devices.

[0003] However, for such organic light-emitting diodes to exhibit the characteristics described above, it is necessary for the materials forming the organic layer within the device—such as hole injection materials, hole transport materials, light-emitting materials, electron transport materials, and electron injection materials—to be supported by stable and efficient materials; yet, the development of stable and efficient organic layer materials for organic light-emitting diodes has not yet been sufficiently achieved.

[0004] Therefore, in order to realize more stable organic light-emitting diodes and to achieve high efficiency, long lifespan, and large scale, further improvements in efficiency and lifespan characteristics are required; in particular, there is an urgent need for the development of materials constituting each organic layer of the organic light-emitting diode.

[0005] Furthermore, recently, in addition to research on improving the characteristics of organic light-emitting diodes by varying the performance of each organic layer material, technologies for enhancing color purity and increasing luminous efficiency through optimized optical thickness between the anode and cathode are being recognized as important factors in improving device performance. As an example of such a method, a light efficiency enhancement layer (capping layer) is used on the electrode to achieve increased light efficiency and excellent color purity.

[0006] The efficiency of organic light emission can be divided into internal light emission efficiency and external light emission efficiency. Internal light emission efficiency is related to the efficiency of exciton generation and light conversion in various organic layers interposed between the first electrode and the second electrode, such as a hole transport layer, an emissive layer, and an electron transport layer. External light emission efficiency is the efficiency of light generated in the organic layer being extracted to the outside of the organic light-emitting device. To increase this light extraction efficiency, a light efficiency improvement layer (capping layer) with a refractive index adjusted to an optimal condition is applied.

[0007] However, there is an urgent need to design and develop an optimized light efficiency improvement layer to realize high-efficiency devices without compromising process efficiency, such as deposition, or other light-emitting characteristics, including device lifespan.

[0008] Accordingly, the present invention aims to provide a material employed in a light efficiency improvement layer (capping layer) provided in an organic light-emitting diode to improve various luminescence characteristics such as low-voltage driving, luminescence efficiency, lifespan, and color purity of the organic light-emitting diode, and a high-efficiency organic light-emitting diode including the same.

[0009] To solve the above problem, the present invention provides an organic compound for a light efficiency improvement layer (capping layer) represented by the following [Chemical Formula I].

[0010] [Chemical Formula I]

[0011]

[0012] The characteristic structure of the above [Chemical Formula I] and the specific compounds realized by it, as well as the definitions of X1, L1 to L3 (m, p, q) and A1 to A2, will be described later.

[0013]

[0014] In addition, the present invention provides an organic light-emitting device comprising a first electrode, a second electrode, and one or more organic layers disposed between the first electrode and the second electrode, wherein the organic light-emitting device further comprises a light efficiency improvement layer (Capping layer) formed on at least one side opposite to the organic layer among the upper or lower portions of the first electrode and the second electrode, and wherein the light efficiency improvement layer comprises an organic compound represented by [Chemical Formula I].

[0015] The organic compound according to the present invention can improve the light efficiency extracted to the outside of the organic light-emitting diode, and thus can be usefully utilized as a material for a light efficiency improvement layer provided in the organic light-emitting diode. Accordingly, by employing the compound according to the present invention in the light efficiency improvement layer, it is possible to realize a high-efficiency, long-life organic light-emitting diode with improved low-voltage driving characteristics as well as improved luminous efficiency, color purity, and lifespan characteristics, which can be usefully utilized in various lighting and display devices.

[0016] FIG. 1 is a schematic cross-sectional view showing the concept and configuration of an organic light-emitting diode according to the present invention.

[0017] FIG. 2 is a schematic cross-sectional view showing the configuration of an organic light-emitting diode according to one embodiment of the present invention.

[0018] FIG. 3 is a schematic cross-sectional view showing the configuration of an organic light-emitting diode according to one embodiment of the present invention.

[0019] The present invention will be described in more detail below.

[0020] The compound for a light efficiency improvement layer according to the present invention is characterized by being a compound that has a moiety having a characteristic structure introduced into a framework structurally represented by [Chemical Formula I].

[0021] Due to these structural features, the organic compound represented by [Chemical Formula I] according to the present invention is used as a capping layer material for improving light efficiency in an organic light-emitting diode, thereby enabling the realization of a high-efficiency organic light-emitting diode with improved low-voltage driving characteristics, as well as improved luminous efficiency, color purity, and lifespan characteristics.

[0022] [Chemical Formula I]

[0023]

[0024] In the above [Chemical Formula I],

[0025] X1 is selected from O, S, SO2 (sulfur dioxide), NR1, CR2R3, SiR4R5 and GeR6R7.

[0026] The above R1 to R7 are identical or different from each other and are each independently selected from hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted heterocycloalkyl group having 3 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 50 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted germanium group, a cyano group, and a halogen group.

[0027] In addition, the above R2 and R3, R4 and R5, and R6 and R7 can each be connected to one another to additionally form aromatic or aliphatic single or polycyclic rings.

[0028]

[0029] L1 to L3 are divalent linkers, which are directly bonded or selected from arylene groups having 6 to 30 carbon atoms that are substituted or unsubstituted and heteroarylene groups having 2 to 50 carbon atoms that are substituted or unsubstituted.

[0030] According to one embodiment of the present invention, L is a divalent linker and may be a direct linkage or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, and more specifically may be a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, or a substituted or unsubstituted naphthylene group.

[0031] m, p, and q are each integers from 0 to 2, and when m, p, and q are 2 or more, a plurality of L1 to L3 are each the same or different from each other.

[0032]

[0033] A1 and A2 are identical or different from each other and are each independently a cyano group (CN), or selected from a substituted or unsubstituted aryl group having 6 to 30 carbon atoms and a substituted or unsubstituted heteroaryl group having 2 to 50 carbon atoms.

[0034]

[0035] According to one embodiment of the present invention, the compound represented by [Chemical Formula I] according to the present invention is characterized in that at least one of A1 and A2 is [Structural Formula 1] or [Structural Formula 2].

[0036] [Structural Formula 1]

[0037]

[0038] [Structural Formula 2]

[0039]

[0040] In the above [Structural Formula 2],

[0041] Y is O or S.

[0042] R 11 to R15 The groups are identical or different from each other and are each independently selected from hydrogen, deuterium, hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted heterocycloalkyl group having 3 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 50 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted germanium group, a cyano group, and a halogen.

[0043] At this time, the above R 11 to R 15 One of them is a site that binds to A1 or A2 of the above [Chemical Formula I].

[0044] In addition, the above R 12 to R 15 Each can be connected to one another or adjacent substituents to additionally form a monocyclic or polycyclic ring of alicyclic or aromatic.

[0045] Accordingly, according to one embodiment of the present invention, [Structural Formula 2] may be any one selected from [Structural Formula 3] to [Structural Formula 6] below.

[0046] [Structural Formula 3] [Structural Formula 4]

[0047]

[0048] [Structural Formula 5] [Structural Formula 6]

[0049]

[0050] In the above [Structural Formula 3] to [Structural Formula 6],

[0051] Y is O or S.

[0052] R 11 to R 23The groups are identical or different from each other and are each independently selected from hydrogen, deuterium, hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted heterocycloalkyl group having 3 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 50 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted germanium group, a cyano group, and a halogen.

[0053] At this time, the above R 11 to R 23 One of them is a site that binds to A1 or A2 of the above [Chemical Formula I].

[0054] According to one embodiment of the present invention, the compound represented by [Chemical Formula I] according to the present invention is characterized in that each of A1 and A2 is [Structural Formula 1] or [Structural Formula 2].

[0055] According to one embodiment of the present invention, A1 and A2 may both be [Structural Formula 1], and A1 and A2 may both be [Structural Formula 2].

[0056]

[0057] In addition, R1 to R7 and R in the above [Chemical Formula I] and [Structural Formula 2] to [Structural Formula 6] 11 to R 23 In the definitions of , A1, A2 and L1 to L3, 'substituted or unsubstituted' refers to the above R1 to R7, R 11 to R 23, A1, A2 and L1 to L3 each mean that they are substituted with one or more substituents selected from deuterium, cyano group, halogen group, hydroxyl group, nitro group, alkyl group, halogenated alkyl group, alkoxy group, halogenated alkoxy group, cycloalkyl group, heterocycloalkyl group, aryl group, heteroaryl group, aliphatic aromatic mixed alkyl group, amine group, silyl group, and germanium group, or that two or more of the said substituents are substituted with a connected substituent, or that they do not have any substituents.

[0058]

[0059] In addition, regarding the definition of 'substituted or unsubstituted' above, specific examples include the term 'substituted aryl group' which means that a phenyl group, a biphenyl group, a naphthalene group, a fluorenyl group, a pyrenyl group, a phenanthrenyl group, a perylene group, a tetracenyl group, anthracenyl group, etc. are substituted with other substituents such as deuterium, and the term 'substituted heteroaryl group' which means that a pyridyl group, a thiophenyl group, a triazine group, a quinoline group, a phenanthroline group, an imidazole group, a thiazole group, an oxazole group, a carbazole group, and condensed heterocyclic groups thereof, such as a benzquinoline group, a benzimidazole group, a benzoxazole group, a benzthiazole group, a benzcarbazole group, a dibenzothiophenyl group, a dibenzofuran group, etc. are also substituted with other substituents such as deuterium.

[0060]

[0061] In addition, the meaning of forming an additional ring by connecting to each other or adjacent groups in the present invention means that adjacent substituents among each specified substituent may combine with each other, or a specified substituent and another adjacent group may combine with each other to form a substituted or unsubstituted alicyclic or aromatic ring, and 'adjacent group' may mean a substituent substituted on an atom directly connected to the atom on which the substituent is substituted, a substituent located closest to the substituent in stereostructure, or another substituent substituted on the atom on which the substituent is substituted. For example, two substituents substituted at the ortho position in a benzene ring and two substituents substituted on the same carbon in an aliphatic ring may be interpreted as 'adjacent groups' to each other.

[0062]

[0063] In the present invention, the alkyl group may be a straight chain or a branched chain, and specific examples include a methyl group, an ethyl group, a propyl group, an n-propyl group, an isopropyl group, a butyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a sec-butyl group, a 1-methyl-butyl group, a 1-ethyl-butyl group, a pentyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a hexyl group, an n-hexyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 4-methyl-2-pentyl group, a 3,3-dimethylbutyl group, a 2-ethylbutyl group, a heptyl group, an n-heptyl group, a 1-methylhexyl group, a cyclopentylmethyl group, a cycloheptylmethyl group, an octyl group, an n-octyl group, a tert-octyl group, a 1-methylheptyl group, a 2-ethylhexyl group. There are, but are not limited to, 2-propylpentyl groups, n-nonyl groups, 2,2-dimethylheptyl groups, 1-ethyl-propyl groups, 1,1-dimethyl-propyl groups, isohexyl groups, 2-methylpentyl groups, 4-methylhexyl groups, 5-methylhexyl groups, etc.

[0064] In the present invention, the alkoxy group may be a straight chain or a branched chain. The number of carbon atoms in the alkoxy group is not particularly limited, but it is preferably 1 to 20, which is within the range that does not cause steric interference. Specifically, it may be a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an i-propyloxy group, an n-butoxy group, an isobutoxy group, a tert-butoxy group, a sec-butoxy group, an n-pentyloxy group, a neopentyloxy group, an isopentyloxy group, an n-hexyloxy group, a 3,3-dimethylbutyloxy group, a 2-ethylbutyloxy group, an n-octyloxy group, an n-nonyloxy group, an n-decyloxy group, a benzyloxy group, a p-methylbenzyloxy group, etc., but is not limited thereto.

[0065] In the present invention, the alkyl group and the alkoxy group may each be a deuterated alkyl group or alkoxy group, a halogenated alkyl group or alkoxy group, and the alkyl group or alkoxy group means an alkyl group or alkoxy group substituted with a deuterated or halogen group.

[0066] In the present invention, the aromatic hydrocarbon ring or aryl group may be monocyclic or polycyclic, and polycyclic means a group that is directly connected to or condensed with another ring group, and the other ring group may be an aromatic hydrocarbon ring, but may also be other types of ring groups, such as an aliphatic heterocycle, an aliphatic hydrocarbon ring, an aromatic heterocycle, etc. Examples of monocyclic aryl groups include phenyl groups, biphenyl groups, terphenyl groups, etc., and examples of polycyclic aryl groups include naphthyl groups, anthracenyl groups, phenanthrenyl groups, pyrenyl groups, perylenyl groups, tetracenyl groups, chrysenyl groups, fluorenyl groups, acenaphthacenyl groups, triphenylene groups, fluoranthene groups, etc., but the scope of the present invention is not limited only to these examples.

[0067] In the present invention, the fluorene in the fluorenyl group or fluorene moiety, etc., is a structure in which two ring organic compounds are connected through one atom, and examples include , , There are others.

[0068] In addition, it includes open fluorene structures, where open fluorene is a structure in which the connection of one ring compound is broken in a structure in which two ring organic compounds are connected through one atom, examples include , There are others.

[0069] In addition, the carbon atoms of the above ring may be substituted with one or more heteroatoms selected from N, S, and O, examples include , , , There are others. In the present invention, the fluorene in the fluorenyl group or fluorene moiety, etc., is a structure in which two ring organic compounds are connected through one atom, and examples include , , There are others.

[0070] In addition, in the present invention, the fluorenyl group may be a structure in which a monocyclic or polycyclic aromatic ring and a monocyclic or polycyclic alicyclic ring, etc. are further condensed into the above-mentioned connected structure or open structure.

[0071] In the present invention, the aromatic heterocycle or heteroaryl group is an aromatic ring comprising one or more heteroatoms, examples thereof include a thiophene group, a furan group, a pyrrole group, an imidazole group, a thiazole group, an oxazole group, an oxadiazole group, a triazole group, a pyridyl group, a bipyridyl group, a pyrimidyl group, a triazine group, a triazole group, an acryl group, a pyridazine group, a pyrazinyl group, a quinolinyl group, a quinazolin group, a quinoxalinyl group, a phthalazinyl group, a pyridopyrimidinyl group, a pyridopyrazinyl group, a pyrazinopyrazinyl group, an isoquinoline group, an indole group, a carbazole group, an indolocarbazole group, a benzoxazole group, a benzimidazole group, a benzothiazole group, a benzocarbazole group, a benzothiophen group, a dibenzothiophen group. There are benzofuranyl groups, dibenzofuranyl groups, phenanthroline groups, thiazolyl groups, isooxazolyl groups, oxadiazoyl groups, thiadiazolyl groups, benzothiazoyl groups, phenothiazinyl groups, etc., but are not limited to these.

[0072] In the present invention, an aliphatic hydrocarbon ring or a cycloalkyl group refers to a ring that is not aromatic and consists only of carbon and hydrogen atoms, and includes, as examples, a monocyclic or polycyclic group, and may be further substituted by other substituents, and a polycyclic group refers to a group that is directly connected to or condensed with another ring group, and the other ring group may be an aliphatic hydrocarbon ring, but may also be other types of ring groups, such as an aliphatic heterocyclic ring, an aromatic hydrocarbon ring, an aromatic heterocyclic ring, etc. Specifically, it includes, but is not limited to, cycloalkyls such as cyclopropyl group, cyclobutyl group, cyclopentyl group, adamantyl group, 3-methylcyclopentyl group, 2,3-dimethylcyclopentyl group, cyclohexyl group, 3-methylcyclohexyl group, 4-methylcyclohexyl group, 2,3-dimethylcyclohexyl group, 3,4,5-trimethylcyclohexyl group, 4-tert-butylcyclohexyl group, cycloheptyl group, cyclooctyl group, etc., cycloalkanes such as cyclohexane, cyclopentane, etc., and cycloalkenes such as cyclohexene, cyclobutene, etc.

[0073] In the present invention, an aliphatic heterocycle or a heterocycloalkyl group refers to an aliphatic ring comprising one or more heteroatoms, and includes heteroatoms such as O, S, Se, N, or Si, and also includes a monocyclic or polycyclic group, and may be further substituted by other substituents, and polycyclic refers to a group in which a heterocycloalkyl, a heterocycloalkane, etc. is directly connected or condensed with another ring group, and the other ring group may be an aliphatic heterocycle, but may also be a different type of ring group, such as an aliphatic hydrocarbon ring, an aromatic hydrocarbon ring, an aromatic heterocycle, etc.

[0074] In the present invention, an aliphatic aromatic mixed ring (group) refers to a ring in which two or more rings are connected and condensed together, and an aliphatic ring and an aromatic ring are condensed to have overall non-aromaticity. More specifically, it may be an aromatic hydrocarbon ring condensed from an aliphatic hydrocarbon ring, an aromatic hydrocarbon ring condensed from an aliphatic hetero ring, an aromatic hetero ring condensed from an aliphatic hydrocarbon ring, an aromatic hetero ring condensed from an aliphatic hetero ring, an aliphatic hydrocarbon ring condensed from an aromatic hydrocarbon ring, an aliphatic hydrocarbon ring condensed from an aromatic hetero ring, an aliphatic hetero ring condensed from an aromatic hetero ring, an aliphatic hetero ring condensed from an aromatic hetero ring, an aliphatic hetero ring condensed from an aromatic hetero ring, an aliphatic hetero ring condensed from an aromatic hetero ring, an aliphatic hetero ring condensed from an aromatic hetero ring, etc. In addition, polycyclic aliphatic-aromatic mixed rings may contain heteroatoms such as N, O, S, Si, Ge, and P in addition to carbon.

[0075] In the present invention, the silyl group is an unsubstituted silyl group or a silyl group substituted with an alkyl group, an aryl group, etc. Specific examples of such silyl groups include trimethylsilyl, triethylsilyl, triphenylsilyl, trimethoxysilyl, dimethoxyphenylsilyl, diphenylmethylsilyl, diphenylvinylsilyl, methylcyclobutylsilyl, dimethylfurylsilyl, etc., but are not limited thereto.

[0076] In the present invention, the germanium group (or germane group) may include -GeH3, alkyl germanium group, aryl germanium group, heteroaryl germanium group, alkylaryl germanium group, alkyl heteroaryl germanium group, aryl heteroaryl germanium group, etc., and their definitions may be applied to each substituent as a substituent obtained by substituting a germanium atom (Ge) instead of a silicon atom (Si) in the silyl group.

[0077] In addition, specific examples of the germanium group include trimethylgermaine, triethylgermaine, triphenylgermaine, trimethoxygermaine, dimethoxyphenylgermaine, diphenylmethylgermaine, diphenylvinylgermaine, methylcyclobutylgermaine, dimethylfurylgermaine, etc., and one or more hydrogen atoms of the germanium group can be substituted with substituents similar to those of the aryl group.

[0078] In the present invention, the amine group may be -NH2, an alkylamine group, an arylamine group, an arylheteroarylamine group, etc., and the arylamine group refers to an amine substituted with an aryl group, the alkylamine group refers to an amine substituted with an alkyl group, and the arylheteroarylamine group refers to an amine substituted with an aryl and a heteroaryl group. Examples of arylamine groups include substituted or unsubstituted monoarylamine groups, substituted or unsubstituted diarylamine groups, or substituted or unsubstituted triarylamine groups. The aryl group and heteroaryl group among the arylamine group and the arylheteroarylamine group may be a monocyclic aryl group, a monocyclic heteroaryl group, or a polycyclic aryl group, a polycyclic heteroaryl group. The arylamine group and arylheteroarylamine group comprising two or more aryl groups and heteroaryl groups may be a monocyclic aryl group (heteroaryl group). It may include a polycyclic aryl group (heteroaryl group), or a monocyclic aryl group (heteroaryl group) and a polycyclic aryl group (heteroaryl group) simultaneously. Additionally, the aryl group and heteroaryl group among the arylamine group and the arylheteroarylamine group may be selected from the examples of aryl groups and heteroaryl groups described above.

[0079] Specific examples of halogen groups used in the present invention include fluorine (F), chlorine (Cl), bromine (Br), etc.

[0080] In addition, various specific examples of substituents according to the present invention can be clearly identified in the specific compounds described below.

[0081]

[0082] The organic compound according to the present invention represented by [Chemical Formula I] above can be used as a light efficiency improvement layer (Capping layer) provided in an organic light-emitting diode due to its structural specificity as described above, and preferred specific examples of the compound represented by [Chemical Formula I] according to the present invention include the following compounds, but are not limited thereto.

[0083]

[0084]

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

[0091]

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

[0098]

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

[0112]

[0113]

[0114]

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121]

[0122]

[0123]

[0124]

[0125]

[0126]

[0127]

[0128]

[0129] As such, the organic compound according to the present invention can be realized by synthesizing an organic compound having various characteristics based on the structural features of the framework and the moiety introduced therein, and as a result, when the organic compound according to the present invention is employed in a light efficiency improvement layer provided in an organic light-emitting diode, the low-voltage driving characteristics of the device, as well as the luminous efficiency, color purity, and lifespan characteristics, can be further improved.

[0130]

[0131] In addition, the compound according to the present invention can be applied to a device according to a general method for manufacturing an organic light-emitting device, and an organic light-emitting device according to one embodiment of the present invention may be formed with a structure including a first electrode, a second electrode, and an organic layer disposed between them, and may be manufactured using a conventional method and materials for manufacturing a device, except that the organic compound according to the present invention is used in the organic layer of the device.

[0132] The organic layer of the organic light-emitting diode according to the present invention may be formed as a single layer structure, but may also be formed as a multilayer structure in which two or more organic layers are stacked. For example, it may have a structure including a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, an electron blocking layer, a hole blocking layer, a light efficiency improvement layer (Capping layer), etc. However, it is not limited thereto and may include a smaller or larger number of organic layers.

[0133]

[0134] An organic light-emitting device according to one embodiment of the present invention is an organic light-emitting device having a capping layer (CPL), comprising a substrate, a first electrode (anode), an organic layer, a second electrode (cathode), and a capping layer, wherein the capping layer may be formed at the bottom of the first electrode (bottom emission) or at the top of the second electrode (top emission).

[0135] According to one embodiment of the present invention, the method of forming a light efficiency improvement layer on top of the second electrode (Top emission) specifically involves light formed in the light-emitting layer being emitted toward the cathode. As the light emitted toward the cathode passes through a light efficiency improvement layer (CPL) formed of a compound according to the present invention with a relatively low refractive index, the wavelength of the light is amplified, and thus the light efficiency is increased.

[0136]

[0137] Specific embodiments of the organic light-emitting diode according to the present invention are as follows with reference to FIGS. 1 to 3 below.

[0138] An organic light-emitting device may be configured to include a substrate (100), a first electrode (210), a second electrode (220), one or more organic layers (310 to 360) interposed between the first electrode and the second electrode, and a light efficiency improvement layer (400), wherein the light efficiency improvement layer may be disposed on the outside of one or more of the first electrode and the second electrode.

[0139] Among the two sides of the first electrode or the second electrode, the side adjacent to the organic layer interposed between the first electrode and the second electrode is called the inner side, and the side not adjacent to the organic material is called the outer side. That is, in the organic light-emitting diode according to the present invention, when a light efficiency improvement layer (400) is placed on the outer side of the first electrode (210), the first electrode (210) is interposed between the light efficiency improvement layer (400) and the organic layer (310 to 360), and when a light efficiency improvement layer (400) is placed on the outer side of the second electrode (220), the second electrode (220) is interposed between the light efficiency improvement layer (400) and the organic layer (310 to 360).

[0140] At this time, as shown in Fig. 3 below, the method of forming a light efficiency improvement layer on the upper side of the second electrode (Top emission) may further include a reflection layer (not shown) to reflect the light emitted between the first electrode (210) and the substrate (100) and additionally emit light toward the upper side of the second electrode.

[0141]

[0142] As such, the organic light-emitting device according to the present invention may have one or more various organic layers interposed on the inner side of the first electrode and the second electrode, and a light efficiency improvement layer may be formed on the outer side of one or more of the first electrode and the second electrode. That is, the light efficiency improvement layer may be formed on both the outer side of the first electrode and the outer side of the second electrode, or may be formed only on the outer side of the first electrode or the outer side of the second electrode.

[0143]

[0144] At this time, the light efficiency improvement layer may include a compound for a light efficiency improvement layer according to the present invention, and may include the compound for a light efficiency improvement layer according to the present invention alone, include two or more types, or include a known compound together, and the thickness of the light efficiency improvement layer may be 100 Å to 4,000 Å.

[0145]

[0146] Additionally, the first light efficiency improvement layer and the second light efficiency improvement layer may each be a multilayer structure in which multiple layers are stacked, and accordingly, a multilayer structure in which multiple first light efficiency improvement layers and multiple second light efficiency improvement layers are stacked may be formed, and in this case, the first light efficiency improvement layer and the second light efficiency improvement layer may be stacked alternately, and the stacking order is not limited.

[0147]

[0148] Meanwhile, in the organic light-emitting diode according to the present invention, the light efficiency improvement layer may have a structure in which a refractive index gradient exists, and the refractive index gradient may gradually decrease towards the outer edge or gradually increase towards the outer edge. To this end, a refractive index gradient can be realized in the light efficiency improvement layer by depositing the light efficiency improvement layer with gradually varying concentrations of the compound for the light efficiency improvement layer according to the present invention.

[0149]

[0150] The specific organic layer structure of the organic light-emitting diode according to the present invention will be explained in more detail in the embodiments described below.

[0151]

[0152] In addition, the organic light-emitting diode according to the present invention can be manufactured by using a PVD (physical vapor deposition) method such as sputtering or electron beam evaporation to form an anode by depositing a metal or a conductive metal oxide or an alloy thereof on a substrate, forming an organic layer including a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer thereon, and then depositing a material that can be used as a cathode thereon.

[0153] In addition to this method, an organic light-emitting diode may be made by sequentially depositing an anode material (210), an organic layer (310 to 360), and a cathode material (220) on a substrate (100). The organic layer may have a multilayer structure including a hole injection layer (310), a hole transport layer (320), an electron blocking layer (330), a light-emitting layer (360), an electron transport layer (350), an electron injection layer (340), etc., but is not limited thereto and may have a single-layer structure. Furthermore, the organic layer may be manufactured with fewer layers by using various polymer materials and a solvent process rather than a deposition method, such as spin coating, dip coating, doctor blading, screen printing, inkjet printing, or thermal transfer.

[0154]

[0155] The above substrate (100) may be a substrate commonly used in organic light-emitting diodes, and in particular may be a transparent glass substrate or a flexible plastic substrate having excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water resistance.

[0156] The anode (210) above is preferably a material with a low work function so that hole injection can be facilitated in an organic layer. Specific examples of anode materials that can be used in the present invention include metals such as vanadium, chromium, copper, zinc, gold or alloys thereof, metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), combinations of metal and oxide such as ZnO:Al or SnO2:Sb, poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDT), conductive polymers such as polypyrrole and polyaniline, but are not limited to these.

[0157] The above-mentioned cathode (220) is preferably a material with a low work function to facilitate electron injection into an organic layer. Specific examples of cathode materials include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead, or alloys thereof, and multilayer materials such as LiF / Al or LiO2 / Al, but are not limited to these.

[0158] The hole injection layer (310) is a material capable of receiving holes from the anode at low voltage, and it is preferable that the HOMO (highest occupied molecular orbital) of the hole injection material is between the work function of the anode material and the HOMO of the surrounding organic layer. Specific examples of hole injection materials include metal porphyrine, oligothiophene, arylamine-based organic materials, hexanitrile hexaazatriphenylene, quinacridone-based organic materials, perylene-based organic materials, anthraquinone, and polyaniline and polythiophene-based conductive polymers, but are not limited to these.

[0159] The hole transport layer (320) is a material capable of receiving holes from the anode or hole injection layer and transferring them to the light-emitting layer, and a material with high mobility for holes is suitable. Specific examples include arylamine-based organic materials, conductive polymers, and block copolymers having both conjugated and non-conjugated portions, but are not limited to these.

[0160] An electron blocking layer (not shown) is a layer that blocks the movement of electrons and can be formed on a hole transport layer, and as the electron blocking layer, a material capable of blocking the movement of electrons without affecting the transport of holes can be used. In addition, a light-emitting layer may be formed on the electron blocking layer, and a hole blocking layer, an electron transport layer, and an electron injection layer may be formed.

[0161] A hole blocking layer (not shown) may be used that can block the movement of holes without affecting electron transport, and examples of such hole blocking layers include TPBi (1,3,5-tri(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl), BCP (2,9-dimethyl4,7-diphenyl-1,10-phenanthroline), CBP (4,4-bis(N-carbazolyl)-1,1'-biphenyl), PBD (2-(4-biphenyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole), PTCBI (bisbenzimidazo[2,1-a:1',2-b']anthra[2,1,9-def:6,5,10-d'e'f']diisoguinoline-10,21-dione), or BPhen Examples include (4,7-diphenyl-1,10-phenanthroline), but are not limited thereto.

[0162] The light-emitting layer (360) is a material capable of emitting light in the visible light region by receiving and combining holes and electrons from the hole transport layer and the electron transport layer, respectively, and is preferably a material with good quantum efficiency for fluorescence or phosphorescence. Specific examples include 8-hydroxy-quinoline aluminum complex (Alq3), carbazole-based compounds, dimerized styryl compounds, BAlq, 10-hydroxybenzoquinoline-metal compounds, benzoxazole, benzthiazole and benzimidazole-based compounds, poly(p-phenylenevinylene) (PPV)-based polymers, spiro compounds, polyfluorene, rubrene, etc., but are not limited to these.

[0163] The electron transport layer (350) is a material that can effectively receive electrons from the cathode and transfer them to the light-emitting layer, and a material with high electron mobility is suitable. Specific examples include Al complexes of 8-hydroxyquinoline, complexes containing Alq3, organic radical compounds, and hydroxyflavone-metal complexes, but are not limited to these.

[0164] The electron injection layer (340) can be formed by depositing an electron injection layer material on top of the electron transport layer, and known materials such as LiF, NaCl, CsF, Li2O, and BaO can be used as the electron injection layer material.

[0165] Additionally, although not illustrated in FIGS. 1 to 3, according to one embodiment of the present invention, an organic layer having various functions may be additionally formed between the light efficiency improvement layer (400) and the first electrode (210) or between the light efficiency improvement layer (400) and the second electrode (220), and an organic layer having various functions may also be additionally formed on the upper and lower (outer surface) of the capping layer (400).

[0166]

[0167] The organic light-emitting device according to the present invention may be a front-emitting type, a back-emitting type, or a double-sided emitting type depending on the material used.

[0168] In addition, the organic compound according to the present invention can also function in organic electronic devices, including organic solar cells, organic photosensitive materials, and organic transistors, on a principle similar to that applied to organic light-emitting diodes.

[0169] The present invention will be described in more detail below with reference to preferred embodiments. However, these embodiments are intended to explain the invention more specifically, and the scope of the invention is not limited by them. It will be obvious to those skilled in the art that various changes and modifications are possible within the scope and spirit of the invention.

[0170]

[0171] Synthesis Example 1: Synthesis of Compound 1

[0172] (1) Preparation Example 1: Synthesis of Intermediate 1-1

[0173]

[0174] 50 g of phenanthrene-9,10-dione and 30.1 g of (4-fluorophenyl)methanamine were added to 500 mL of DMSO, stirred, and heated to 200 °C. After confirming the completion of the reaction by TLC and HPLC, the mixture was cooled to room temperature and solidified by adding EtOH. Subsequently, the mixture was filtered and thoroughly washed with EtOH to obtain 35 g (yield 47%) of the yellow intermediate 1-1.

[0175]

[0176] (2) Preparation Example 2: Synthesis of Intermediate 1-2

[0177]

[0178] 10 g of intermediate 1-2, 8.7 g of 3,6-dibromo-9H-carbazole, and 27.3 g of K3PO4 were added to DMF and stirred. Subsequently, the mixture was heated to 150 °C and reacted for 36 hours. After confirming the completion of the reaction by TLC and HPLC, the reaction mixture was added to water and stirred. The solid obtained by filtration was then purified using a silicagel column to obtain 13 g (yellow solid) of intermediate 1-2 (yellow solid) (yield 65%).

[0179]

[0180] (3) Preparation Example 3: Synthesis of Compound 1

[0181]

[0182] 6 g of intermediate 1-2, 4.6 g of benzo[d]oxazole, 5.4 g of K2CO3, 0.04 g of Pd cat., 20.7 g of Cu(OAc)2, and 32.5 g of PPh were added to xylene and stirred. The temperature was raised to 160 °C and heated for 12 hours. After confirming the termination of the reaction by TLC and HPLC, the mixture was cooled and filtered. Subsequently, 4.3 g of Compound 1 (yield 64%) was obtained by recrystallization following silicagel column purification. LC / MS: m / z=695[(M)+]

[0183]

[0184] Synthesis Example 2: Synthesis of Compound 16

[0185] (1) Preparation Example 1: Synthesis of Compound 16

[0186]

[0187] 7 g of intermediate 1-2, 6.1 g of benzo[d]thiazole, 6.3 g of K2CO3, 0.05 g of Pd cat., 20.8 g of Cu(OAc)2, and 33.0 g of PPh were added to xylene and stirred. The temperature was raised to 160 ℃ and heated for 12 hours. After confirming the completion of the reaction by TLC and HPLC, the mixture was cooled and filtered. Subsequently, 4.1 g of compound 16 (yield 50%) was obtained by purification with a silicagel column and recrystallization.

[0188] LC / MS: m / z=727[(M)+]

[0189]

[0190] Synthesis Example 3: Synthesis of Compound 35

[0191] (1) Preparation Example 1: Synthesis of Intermediate 35-1

[0192]

[0193] 20 g of phenanthrene-9,10-dione and 16.8 g of (6-fluoronaphthalen-2-yl)methanamine were added to DMSO, stirred, and heated to 200 ℃. After confirming the completion of the reaction by TLC and HPLC, the mixture was cooled to room temperature and solidified by adding EtOH. Subsequently, the mixture was filtered and thoroughly washed with EtOH to obtain 16.7 g (yield 48%) of the yellow intermediate 35-1.

[0194]

[0195] (2) Preparation Example 2: Synthesis of Intermediate 35-2

[0196]

[0197] 16.7 g of intermediate 35-1, 12.4 g of 3,6-dibromo-9H-carbazole, and 32.5 g of K3PO4 were added to DMF and stirred. Subsequently, the mixture was heated to 150 ℃ and reacted for 36 hours. After confirming the completion of the reaction by TLC and HPLC, the reaction mixture was added to water and stirred. The solid obtained by filtration was then purified using a silicagel column to obtain 21 g (yellow solid) of intermediate 35-2 (yellow solid) (yield 74%).

[0198]

[0199] (3) Preparation Example 3: Synthesis of Compound 35

[0200]

[0201] 21 g of intermediate 35-2, 17 g of benzo[d]thiazole, 17.4 g of K2CO3, 0.14 g of Pd cat., 22.3 g of Cu(OAc)2, and 38.2 g of PPh were added to xylene and stirred. The temperature was raised to 160 ℃ and heated for 12 hours. After confirming the completion of the reaction by TLC and HPLC, the mixture was cooled and filtered. Subsequently, the mixture was purified by a silicagel column and recrystallized to obtain 12.6 g (yield 52%) of compound 35.

[0202] LC / MS: m / z=777[(M)+]

[0203]

[0204] Synthesis Example 4: Synthesis of Compound 49

[0205] (1) Preparation Example 1: Synthesis of Intermediate 49-1

[0206]

[0207] 10 g of intermediate 1-1, 8.7 g of 3,6-dibromo-9H-carbazole, and 27.3 g of K3PO4 were added to DMF and stirred. The mixture was then heated to 150 ℃ and reacted for 36 hours. After confirming the completion of the reaction by TLC and HPLC, the reaction mixture was added to water and stirred. Subsequently, the solid obtained by filtration was purified using a silicagel column to obtain 12.5 g (yellow solid) of intermediate 49-1 (yellow solid) (yield 63%).

[0208]

[0209] (2) Preparation Example 2: Synthesis of Intermediate 49

[0210]

[0211] 12.5 g of intermediate 49-1, 7.1 g of (4-cyanophenyl)boronic acid, 16.8 g of potassium carbonate(aq), and 1.4 g of Pd cat. were added to toluene and dioxane and stirred. Subsequently, the temperature was raised to 105 ℃ and stirred for 12 hours. After confirming the completion of the reaction by TLC and HPLC, extraction was performed using MC and water. The organic layer was then separated and concentrated, and the resulting solid was column purified to obtain 7.8 g (yield 58%) of compound 49.

[0212] LC / MS: m / z=663[(M)+]

[0213]

[0214] Synthesis Example 5: Synthesis of Compound 155

[0215] (1) Preparation Example 1: Synthesis of Intermediate 155-1

[0216]

[0217] 20 g of 1-(4-fluorophenyl)ethan-1-one, 13.2 g of benzothioamide, 372.5 g of KBrO, and 10 mol% of lipase were added to H2O at 35 ℃ and stirred for 10 minutes. After confirming the completion of the reaction by TLC and HPLC, the organic layer was concentrated by extraction with MC and H2O. Subsequently, the solid was solidified with EtOH to obtain a solid of intermediate 155-127 g (yield 73%).

[0218]

[0219] (2) Preparation Example 2: Synthesis of Intermediate 155-2

[0220]

[0221] 27 g of intermediate 155-1, 16.6 g of 1,2-dibromobenzene, 39 g of K2CO3, 0.8 g of Pd cat., and 2.0 g of Pcy3H·BF3 were added to dimethylacetamide and stirred. The temperature was raised to 140 ℃ and heated for 14 hours. After confirming the completion of the reaction by TLC and HPLC, the mixture was cooled and filtered. Subsequently, after purification by silicagel column, the mixture was recrystallized to obtain 20 g (yield 57%) of intermediate 155-2.

[0222]

[0223] (3) Preparation Example 3: Synthesis of Intermediate 155-3

[0224]

[0225] 20 g of intermediate 155-2, 16.4 g of 3,6-dibromo-9H-carbazole, and 443 g of K3PO were added to DMF and stirred. The mixture was then heated to 150 ℃ and reacted for 36 hours. After confirming the completion of the reaction using TLC and HPLC, the reaction mixture was added to water and stirred. Subsequently, the solid obtained by filtration was purified using a silicagel column to obtain 26.3 g (yellow solid) of intermediate 155-3 (yellow solid) (yield 68%).

[0226]

[0227] (4) Preparation Example 4: Synthesis of Compound 155

[0228]

[0229] 13.9 g of intermediate 155-3, 10.4 g of benzo[d]oxazole, 12.1 g of K2CO3, 0.10 g of Pd cat., 21.6 g of Cu(OAc)2, and 35.7 g of PPh were added to xylene and stirred. The temperature was raised to 160 ℃ and heated for 12 hours. After confirming the completion of the reaction by TLC and HPLC, the mixture was cooled and filtered. Subsequently, after purification by silicagel column, the mixture was recrystallized to obtain 7.3 g (yield 47%) of compound 155.

[0230] LC / MS: m / z=711[(M)+]

[0231]

[0232] Synthesis Example 6: Synthesis of Compound 182

[0233] (1) Preparation Example 1: Synthesis of Compound 182

[0234]

[0235] 12.4 g of intermediate 3-2, 8.1 g of naphthalen-2-ylboronic acid, 16.2 g of potassium carbonate(aq), and 1.4 g of Pd cat. were added to toluene and dioxane and stirred. Subsequently, the temperature was raised to 105 ℃ and stirred for 12 hours. After confirming the completion of the reaction by TLC and HPLC, extraction was performed using MC and water. The organic layer was then separated and concentrated, and the resulting solid was column purified to obtain 8.1 g (yield 57%) of compound 182.

[0236] LC / MS: m / z=729[(M)+]

[0237]

[0238] Synthesis Example 7: Synthesis of Compound 251

[0239] (1) Preparation Example 1: Synthesis of Intermediate 251-1

[0240]

[0241] 10 g of phenanthrene-9,10-dione, 22.4 g of aniline, 6 g of 4-fluorobenzaldehyde, and 14.81 g of 60% ammonium acetate were added to AcOH and stirred. Subsequently, the mixture was heated to 110 ℃ and stirred for 4 hours, after which the results were confirmed by TLC and HPLC. After cooling, the reaction mixture was added to H2O, and the solid was filtered and purified using a silicagel column to obtain 10.3 g of intermediate 251-1 (yield 55%).

[0242]

[0243] (2) Preparation Example 2: Synthesis of Intermediate 251-2

[0244]

[0245] 10.3 g of intermediate 251-1, 7.2 g of 3,6-dibromo-9H-carbazole, and 18.8 g of K3PO4 were added to DMF and stirred. Subsequently, the mixture was heated to 150 ℃ and reacted for 36 hours. After confirming the completion of the reaction by TLC and HPLC, the reaction mixture was added to water and stirred. The solid obtained by filtration was then purified using a silicagel column to obtain 13.3 g (yield 72%) of intermediate 251-2.

[0246]

[0247] (3) Preparation Example 3: Synthesis of Compound 251

[0248]

[0249] 13.3 g of intermediate 251-2, 10.0 g of benzo[d]oxazole, 11.6 g of K2CO3, 0.09 g of Pd cat., 21.5 g of Cu(OAc)2, and 35.5 g of PPh were added to xylene and stirred. The temperature was raised to 160 ℃ and heated for 12 hours. After confirming the completion of the reaction by TLC and HPLC, the mixture was cooled and filtered. Subsequently, after purification by silicagel column, the mixture was recrystallized to obtain 6.9 g (yield 46%) of compound 251.

[0250] LC / MS: m / z=770[(M)+]

[0251]

[0252] Synthesis Example 8: Synthesis of Compound 337

[0253] (1) Preparation Example 1: Synthesis of Compound 337

[0254]

[0255] 3.5 g of compound 155 was added to H2O2 and stirred for 10 hours, after which the results were confirmed by TLC and HPLC. Subsequently, 3.1 g of compound 337 (yield 85%) was obtained by filtering and recrystallizing MCB.

[0256] LC / MS: m / z=743[(M)+]

[0257]

[0258] Synthesis Example 9: Synthesis of Compound 345

[0259] (1) Preparation Example 1: Synthesis of Compound 345

[0260]

[0261] 4.0 g of compound 182 was added to H2O2 and stirred for 12 hours, after which the results were confirmed by TLC and HPLC. Subsequently, 3.3 g of compound 345 (yield 79%) was obtained by filtering and recrystallizing MCB.

[0262] LC / MS: m / z=761[(M)+]

[0263]

[0264] Synthesis Example 10: Synthesis of Compound 367

[0265] (1) Preparation Example 1: Synthesis of Compound 367

[0266]

[0267] 7 g of intermediate 1-2, 5 g of (4-cyanophenyl)boronic acid, and 1.58 g of Pd cat. were added to toluene, followed by the addition of 6.3 g of potassium carbonate (aqueous solution) and ethanol, the temperature was raised to 80 ℃, and the mixture was stirred for 12 hours. After the reaction was completed by TLC and HPLC, the mixture was cooled to room temperature, filtered, and recrystallized in monochlorobenzene to obtain 3.5 g of compound 367 (yield 46%).

[0268] LC / MS: m / z=663[(M)+]

[0269]

[0270] Experimental Example: Optical properties of the compound according to the present invention

[0271] In an experimental example according to the present invention, a quartz glass having dimensions of 25 mm × 25 mm was cleaned. Then, it was mounted in a vacuum chamber and the base pressure was 1 × 10 -6 When the torr exceeded a certain level, the compound according to the present invention and the comparative compound were each deposited on a glass substrate to measure the optical properties.

[0272]

[0273] Examples 1 to 10

[0274] As compounds used in the light efficiency improvement layer provided in an organic light-emitting diode, compounds according to the present invention described in [Table 1] below were each deposited at a thickness of 100 nm on a glass substrate and their refractive indices were measured.

[0275] Quartz glass / Organic (100 nm)

[0276]

[0277] Comparative Example 1

[0278] The substrate for Comparative Example 1 was prepared in the same manner except that the following [CP1] was used instead of the compounds of Examples 1 to 10, and optical properties were measured.

[0279]

[0280] Experimental Example 1: Optical properties of compounds in Examples 1 to 10

[0281] The refractive index of the substrates fabricated according to the above examples and comparative examples was measured using Ellipsometry (Elli-SE). The refractive index was measured in the blue (450 nm) wavelength region, and the results are shown in [Table 1] below.

[0282] Refractive Index (450 nm) Example 1 (Compound 1) 2.39 Example 2 (Compound 16) 2.56 Example 3 (Compound 35) 2.44 Example 4 (Compound 49) 2.51 Example 5 (Compound 155) 2.40 Example 6 (Compound 182) 2.33 Example 7 (Compound 251) 2.53 Example 8 (Compound 337) 2.32 Example 9 (Compound 345) 2.30 Example 10 (Compound 367) 2.60 Comparative Example 1 (CP1) 1.70

[0283] Looking at [Table 1] above, the compound according to the present invention has a refractive index value at a wavelength of 450 nm that is significantly higher than that of Comparative Example 1, which is a conventional light efficiency improvement layer material. When the compound according to the present invention, which has such a high refractive index value, is adopted in the light efficiency improvement layer provided in an organic light-emitting diode, optimization of the device's efficiency can be expected.

[0284]

[0285] [CP1]

[0286]

[0287] Device Example (CPL)

[0288] In an embodiment according to the present invention, the anode was patterned using an Ag-containing ITO glass substrate of 25 mm × 25 mm × 0.7 mm to have a light-emitting area of ​​2 mm × 2 mm, and then cleaned. After mounting the patterned ITO substrate in a vacuum chamber, 1 × 10 -6 Organic materials and metals were deposited on a substrate with the following structure at a process pressure of torr or higher.

[0289]

[0290] Device Examples 11 to 37

[0291] A compound implemented according to the present invention was employed in a light efficiency improvement layer (single-layer CPL) provided in a device, and after fabricating a blue organic light-emitting diode having the device structure as described below, the light emission and driving characteristics were measured.

[0292]

[0293] Ag / ITO / Hole injection layer (HAT-CN, 5 nm) / Hole transport layer (HT1, 100 nm) / Electron blocking layer (EB1, 10 nm) / Emitting layer (20 nm) / Electron transport layer (ET1:Liq, 30 nm) / LiF (1 nm) / Mg:Ag (15 nm) / Photometric efficiency enhancement layer (65 nm)

[0294]

[0295] After forming a hole injection layer by depositing [HAT-CN] to a thickness of 5 nm on an Ag-containing ITO transparent electrode on a glass substrate, a hole transport layer was formed by depositing [HT1] to a thickness of 100 nm, and then an electron blocking layer was formed by depositing [EB1] to a thickness of 10 nm. Subsequently, an emissive layer was formed by co-depositing [BH1] as the host compound and [BD1] as the dopant compound to a thickness of 20 nm. Afterward, an electron transport layer (doped with 50% Liq of the [ET1] compound below) was deposited to a thickness of 30 nm, and then an electron injection layer was formed by depositing LiF to a thickness of 1 nm. Subsequently, a cathode was formed by depositing Mg:Ag to a thickness of 15 nm in a ratio of 1:9.

[0296] In addition, an organic light-emitting diode was fabricated by forming a capping layer with a thickness of 65 nm using a compound [Chemical Formula I] according to the present invention as described in [Table 2] below.

[0297]

[0298] Device Comparison Example 2

[0299] The organic light-emitting device of Comparative Example 2 was manufactured in the same manner as the device structures of Examples 11 to 37, except that it does not have a light efficiency improvement layer.

[0300]

[0301] Device Comparison Example 3

[0302] The organic light-emitting diode of Comparative Example 3 was fabricated in the same manner as the device structures of Examples 11 to 37, except that the following [CP1] was used instead of the compound according to the present invention as the light efficiency improvement layer compound.

[0303]

[0304] Experimental Example 2: Luminescence characteristics of device Examples 11 to 37

[0305] For the organic light-emitting diodes manufactured according to the above examples and comparative examples, the driving voltage, current efficiency, and color coordinates were measured using a source meter (Model 237, Keithley) and a luminance meter (PR-650, Photo Research), and the results based on 1,000 nit are as shown in [Table 2] below.

[0306] Example Photometric efficiency improvement layer Vcd / ACIExCIEy11 Compound 13.618.210.12980.149112 Compound 163.888.600.13450.146713 Compound 353.578.190.14040.141314 Compound 493.728.470.14220.139215 Compound 573.998.300.13110.149916 Compound 663.818.660.14930.134717 Compound 743.748.590.15250.132918 Compound 923.968.720.14860.135819 Compound 1013.668.350.13870.143420 Compound 1153.588.620.14180.140421 Compound 1203.548.290.14350.138922 Compound 1273.828.790.15050.133623 Compound 1383.648.670.13060.148824 Compound 1423.78.370.13600.144825 Compound 1493.558.240.13740.144326 Compound 1553.98.750.15150.133327 Compound 1823.678.260.13360.147928 Compound 2513.768.420.14580.137429 Compound 2873.788.580.15390.132130 Compound 3003.68.770.15470.130531 Compound 3043.538.140.14090.141332 Compound 3373.658.630.13240.148233 Compound 3453.778.520.14610.136634 Compound 3673.738.230.15530.130335 Compound 3683.88.640.14420.137736 Compound 3673.688.380.14760.136237 Compound 3683.628.450.13980.1425 Comparative Example 2 Not provided 4.617.120.14970.1372 Comparative Example 3 CP1 4.047.970.13620.1298

[0307] As shown in [Table 2] above, when the compound [Chemical Formula I] according to the present invention is applied to a device as a light efficiency improvement layer, it can be confirmed that the driving voltage is reduced and the current efficiency is improved compared to each of the conventional device without a light efficiency improvement layer and the device using the compound used as a conventional light efficiency improvement layer material (Comparative Examples 2 to 3).

[0308] [HAT_CN] [HT1] [BH1] [BD1] [ET1]

[0309]

[0310] [EB1] [CP1]

[0311]

[0312] The organic compound according to the present invention can improve the light efficiency extracted to the outside of the organic light-emitting diode, and thus can be usefully utilized as a material for a light efficiency improvement layer provided in the organic light-emitting diode. Accordingly, when the compound according to the present invention is employed in the light efficiency improvement layer, a high-efficiency and long-life organic light-emitting diode with improved low-voltage driving characteristics, as well as improved luminous efficiency, color purity, and lifespan characteristics, can be realized, making it industrially useful for various lighting and display devices.

Claims

Organic compound represented by the following [Chemical Formula I]: [Chemical Formula I] In the above [Chemical Formula I], X1 is any one selected from O, S, SO2 (sulfur dioxide), NR1, CR2R3, SiR4R5 and GeR6R7, and The above R1 to R7 are identical or different from each other and are each independently selected from hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted heterocycloalkyl group having 3 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 50 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted germanium group, a cyano group, and a halogen group. The above R2 and R3, R4 and R5, and R6 and R7 can each be connected to one another to additionally form aromatic or aliphatic single or polycyclic rings, and L1 to L3 are divalent linkers, either directly bonded or selected from a substituted or unsubstituted arylene group having 6 to 30 carbon atoms and a substituted or unsubstituted heteroarylene group having 2 to 50 carbon atoms, and m, p, and q are each integers from 0 to 2, and if m, p, and q are 2 or greater, a plurality of L1 to L3 are each identical or different from each other, and A1 and A2 are identical or different from each other and are each independently a cyano group (CN), or any one selected from a substituted or unsubstituted aryl group having 6 to 30 carbon atoms and a substituted or unsubstituted heteroaryl group having 2 to 50 carbon atoms. In paragraph 1, An organic compound characterized in that at least one of the above A1 and A2 is the following [Structural Formula 1] or [Structural Formula 2]: [Structural Formula 1] [Structural Formula 2] In the above [Structural Formula 2], Y is O or S, and R 11 to R 15 The groups are identical or different from one another and are each independently selected from hydrogen, deuterium, hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted heterocycloalkyl group having 3 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 50 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted germanium group, a cyano group, and a halogen. The above R 12 to R 15 Each can be connected to each other or adjacent substituents to additionally form alicyclic or aromatic single or polycyclic rings, and The above R 11 to R 15 One of them is a site that binds to A1 or A2 of the above [Chemical Formula I]. In paragraph 1, An organic compound characterized in that the above L1 to L3 are divalent linkers, which are directly substituted or unsubstituted arylene groups having 6 to 30 carbon atoms. In paragraph 2, An organic compound characterized in that the above A1 and A2 are each [Structural Formula 1] or [Structural Formula 2]. In paragraph 1 or 2, R1 to R7 and R in the above [Chemical Formula I] and [Structural Formula 2] 11 to R 15 In the definitions of , A1, A2 and L1 to L3, 'substituted or unsubstituted' refers to the above R1 to R7, R 11 to R 15 An organic compound wherein A1, A2 and L1 to L3 are each substituted with one or more substituents selected from deuterium, cyano group, halogen group, hydroxyl group, nitro group, alkyl group, halogenated alkyl group, alkoxy group, halogenated alkoxy group, cycloalkyl group, heterocycloalkyl group, aryl group, heteroaryl group, aliphatic aromatic mixed alkyl group, amine group, silyl group, and germanium group, or are substituted with a substituent in which two or more of the said substituents are connected, or have no substituents. In paragraph 1, The above [Chemical Formula I] is any one organic compound selected from [Compound 1] to [Compound 371] below: An organic light-emitting device comprising a first electrode, a second electrode, and one or more organic layers disposed between the first electrode and the second electrode, It further includes a light efficiency improvement layer (Capping layer) formed on at least one side opposite to the organic layer among the upper or lower portions of the first electrode and the second electrode, and An organic light-emitting diode characterized in that the light efficiency improvement layer comprises a compound represented by [Chemical Formula I]. In Paragraph 7, The above light efficiency improvement layer is an organic light-emitting device disposed on the outer side of one or more of the first electrode and the second electrode.

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