KR102815816B1 - An electroluminescent compound and an electroluminescent device comprising the same - Google Patents

Abstract

The present invention relates to an organic light-emitting compound which is a p-doping material for a hole transport material represented by the following [Chemical Formula I] or [Chemical Formula II], or a multi-functional HTL (Multi-functional HTL) compound having a fused structure capable of both p-doping and hole transport functions, and which can form a single hole layer of a multi-functional HTL (Multi-functional Hole Transportation Layer), and an organic light-emitting device employing the same which can be driven at low voltage and has significantly improved luminous efficiency and lifespan characteristics.
[Chemical Formula I] [Chemical Formula II]

Description

Organic electroluminescent compound and organic electroluminescent device comprising the same {An electroluminescent compound and an electroluminescent device comprising the same}

The present invention relates to an organic light-emitting compound employed in a hole layer of an organic light-emitting device, and more specifically, to an organic light-emitting compound which is a p-doping material for a hole transport material, or a multi-functional HTL (Multi-functional HTL) compound having a fused structure capable of performing both p-doping and hole transport functions, which can form a single hole layer of a multi-functional HTL (Multi-functional Hole Transportation Layer), and an organic light-emitting device employing the same which can be driven at low voltage and has significantly improved light emission efficiency and lifespan characteristics.

Recently, organic light-emitting diodes that are self-luminous and can be driven at low voltage have superior viewing angles and contrast ratios compared to liquid crystal displays, which are the mainstream flat panel display devices, and they do not require a backlight, are lightweight and thin, are advantageous in terms of power consumption, and have a wide color reproducibility range, and are thus attracting attention as next-generation display devices.

An organic light-emitting device is a device that emits light when electrons and holes pair up and then annihilate each other when a charge is injected into an organic light-emitting layer formed between an electron-injection electrode (cathode) and a hole-injection electrode (anode). Not only can the device be formed on a flexible transparent substrate such as plastic, but compared to plasma display panels or inorganic light-emitting displays, it can be driven at a low voltage of 10 V or less, consumes relatively little power, and has the advantages of excellent color reproduction. In addition, since organic light-emitting devices can display three colors, green, blue, and red, they are attracting much attention as next-generation rich-color display devices.

Organic light-emitting devices use different organic layers to each perform a role in the process of emitting light, that is, charge injection, charge transport, formation of photoexcitons, and light generation. Accordingly, organic light-emitting devices having a structure that is subdivided into more layers, such as a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer, are used between the anode and the cathode. In order for the organic light-emitting device to exhibit the above-mentioned characteristics, the materials that make up the organic layers within the device, such as hole injection materials, hole transport materials, light-emitting materials, electron transport materials, electron injection materials, and electron blocking materials, must first be supported by stable and efficient materials. However, stable and efficient organic layer materials for organic light-emitting devices have not yet been sufficiently developed.

Accordingly, in order to realize more stable organic light-emitting devices and to achieve high efficiency, long life, and large-scale development of the devices, additional improvements in efficiency and life characteristics are required. In relation to this, research has been conducted recently to dope the hole transport layer material in the structure of the organic light-emitting device with a p-type material to improve the conductivity (mobility) of existing organic materials, or to subdivide the layers to further provide a layer containing a p-type material between the electrode and the hole transport layer.

In particular, doping with organic materials forms negative conductivity, which can lower the voltage drop in the transport layer even if it is a thick transport layer, and a thin space charge layer formed by increasing the doping level enables effective charge injection by tunneling. Doping the hole transport layer can control the high conductivity of the hole transport layer and the charge density of the charge carriers, and ultimately the conductivity of the organic layer is improved, which improves the characteristics of the device, and allows for the implementation of a device with low operating voltage and high efficiency.

However, there are still problems such as a decrease in process efficiency due to the application of additional organic materials and organic layers, and difficulty in implementing low-voltage operation due to problems with the thickness of the organic layer.

Accordingly, the present invention is intended to solve the above problems by providing a p-type doping material for a hole transport material, and further providing a multifunctional HTL (Multi-functional HTL) compound having a fused structure capable of performing both p-doping and hole transport without separately performing p-doping on the hole transport material, thereby providing an organic light-emitting device forming a single hole layer of a multifunctional HTL (Multi-functional Hole Transportation Layer), thereby stably implementing characteristics such as improved luminous efficiency and long lifespan, and implementing low-voltage operation at a level equivalent to or higher than that of conventional devices.

In order to solve the above problem, the present invention provides an organic light-emitting compound represented by the following [chemical formula I] or [chemical formula II] and an organic light-emitting device including at least one light-emitting compound represented by the following [chemical formula I] or [chemical formula II] in an organic layer.

The compound of [Chemical Formula I] or [Chemical Formula II] according to the present invention can be a p-type doping material of a hole transport material, and is further characterized by being a multifunctional HTL compound that introduces moieties having a p-doping function and a hole transport property into one structure, that is, includes a hole transport moiety (Hole Transportation Unit) and a p-doping moiety (p-Dopant Unit) by fusing them.

[Chemical Formula I] [Chemical Formula II]

The specific structure and substituents of the compound represented by the above [Chemical Formula I] or [Chemical Formula II] are described later.

In addition, the present invention provides an organic light-emitting device comprising an anode, a cathode, and a plurality of organic layers placed in contact between the anode and the cathode, and characterized in that the plurality of organic layers include an organic light-emitting compound according to the present invention.

In particular, the plurality of organic layers are composed of a plurality of layers having various properties, such as an electronic layer, an emission layer, and a hole layer, and according to one embodiment of the present invention, the hole layer is a multifunctional HTL (Hole Transportation Layer), characterized in that it employs a multifunctional HTL (Holistic HTL) compound according to the present invention including a hole transportation unit and a p-dopant unit.

When the organic light-emitting compound according to the present invention is employed as a p-type doping material in a hole transport layer of an organic light-emitting device, it can realize remarkably excellent light-emitting characteristics such as light efficiency and quantum efficiency, and thus can be usefully used in various display devices.

In addition, the organic light-emitting compound according to the present invention is a multifunctional HTL compound that combines p-doping function and hole transport characteristics, and is characterized in that it can be configured as a single hole layer (multifunctional HTL), so that a device introducing the same can improve hole transport without separate p-doping compared to a conventional device, and accordingly can implement improved luminous efficiency and low-voltage operation equivalent to or higher than that of a conventional device, and thus can be usefully utilized in various display devices. In addition, since a process for providing a separate p-type layer or a p-doping process is not required compared to a conventional device, the efficiency of the device manufacturing process can also be improved.

Figure 1 is a representative diagram showing the structure of an organic light-emitting compound according to the present invention.

Hereinafter, the present invention will be described in more detail.

One aspect of the present invention relates to an organic light-emitting compound represented by the following [chemical formula I] or [chemical formula II].

[Chemical Formula I] [Chemical Formula II]

In the above [chemical formula Ⅰ] or [chemical formula Ⅱ],

X ₁ is any one selected from O, S, R ₁₃ -CR ₁₄ , R ₁₅ -Si-R ₁₆ and NR ₁₇ , X ₂ is CR ₁₉ or N, and X ₃ and X ₄ can each independently be any one selected from O, S, R ₂₀ -CR ₂₁ , R ₂₂ -Si-R ₂₃ and NR ₂₄ .

A and B may be the same or different and may be independently selected from the following [structural formula 1].

[Structural formula 1]

In the above [structural formula 1],

R ₁ to R ₄ are each independently any one selected from a halogen group, a cyano group, a nitro group, a sulfonyl group (SO ₂ R'), a sulfoxide group (SO ₃ ), a carbonyl group (COR'), a carboxyl group (CO ₂ R'), hydrogen, deuterium, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, and a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms.

The above R' is selected from hydrogen, deuterium, a cyano group, a halogen group, an amino group, a thiol group, a hydroxy group, a nitro group, an alkyl group having 1 to 24 carbon atoms, a halogenated alkyl group having 1 to 24 carbon atoms, an alkenyl group having 2 to 24 carbon atoms, an aryl group having 6 to 24 carbon atoms, a heteroaryl group having 2 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, an alkylsilyl group having 1 to 24 carbon atoms, and an arylsilyl group having 1 to 24 carbon atoms.

R is selected from hydrogen, deuterium, a cyano group, a halogen group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted arylamine group having 6 to 50 carbon atoms, and a substituted or unsubstituted heteroarylamine group having 3 to 50 carbon atoms.

R ₅ to R ₂₄ are each independently selected from hydrogen, deuterium, a halogen group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted arylamine group having 6 to 50 carbon atoms, and a substituted or unsubstituted heteroarylamine group having 3 to 50 carbon atoms.

In addition, according to one embodiment of the present invention, in the [chemical formula I], two R are the same as or different from each other, and are each selected from the following [structural formula 2] and [structural formula 3], and are preferably each represented by the following [structural formula 2].

[Structural formula 2]

[Structural formula 3]

In the above [structural formula 2] and [structural formula 3],

L ₁ and L ₂ are each a single bond or are selected from a substituted or unsubstituted arylene group having 6 to 30 carbon atoms and a substituted or unsubstituted heteroarylene group having 2 to 30 carbon atoms, n and m are each an integer of 0 to 4, and when n and m are each 2 or more, a plurality of L ₁ and L ₂ are each the same as or different from each other.

Ar ₁ to Ar ₃ are the same or different, and are each independently selected from a substituted or unsubstituted aryl group having 5 to 50 carbon atoms and a substituted or unsubstituted heteroaryl group having 2 to 50 carbon atoms.

The above Ar ₁ and Ar ₂ may be bonded to each other or linked to adjacent substituents to form an alicyclic or aromatic monocyclic or polycyclic ring, and the carbon atoms of the formed alicyclic or aromatic monocyclic or polycyclic ring may be substituted with at least one heteroatom selected from N, S, and O.

o, p and q are each integers from 1 to 3, and when o, p and q are each 2 or greater, a plurality of Ar ₁ to Ar ₃ are each the same or different from each other.

In addition, according to one embodiment of the present invention, at least one of R ₅ to R ₈ and at least one of R ₉ to R ₁₂ in the above [chemical formula II] are the same as or different from each other, and are each selected from the above [structural formula 2] and [structural formula 3], and are preferably each represented by the following [structural formula 2].

Meanwhile, R, R ₁ to R ₂₄ , L ₁ , L ₂ and Ar ₁ to Ar ₃ may be further substituted with one or more substituents, each of which is selected from the group consisting of hydrogen, deuterium, an amino group, a cyano group, a hydroxy group, a nitro group, a halogen group, an amide group, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a heterocycloalkyl group having 2 to 20 carbon atoms, a halogenated alkyl group having 1 to 24 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 30 carbon atoms, an alkylthioxy group having 1 to 30 carbon atoms, an arylthioxy group having 5 to 30 carbon atoms, an alkylamine group having 1 to 30 carbon atoms, an arylamine group having 5 to 30 carbon atoms, It may be selected from an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 3 to 30 carbon atoms, an aryl group having 6 to 50 carbon atoms fused with at least one cycloalkyl having 3 to 20 carbon atoms, a heteroaryl group having 6 to 50 carbon atoms fused with at least one cycloalkyl having 3 to 20 carbon atoms, and a silyl group.

The organic light-emitting compound represented by [Chemical Formula I] or [Chemical Formula II] according to the present invention can be employed in various organic layers in an organic light-emitting device, but according to a preferred embodiment, it can be utilized alone as a material employed in a hole transport layer in an organic light-emitting device, and can also be utilized as a p-type dopant for doping a compound having a hole transport function.

P-type refers to p-type semiconductor characteristics. P-type is a characteristic of injecting or transporting holes through the HOMO (highest occupied molecular orbital) energy level, and this is defined as a characteristic of a material in which the mobility of holes is greater than the mobility of electrons. P-type doping means that it has been doped to have these p-type characteristics.

In particular, in the past, in order to control the high conductivity of a hole transport layer formed on an ITO substrate and the charge density of charge carriers, a p-type dopant was used for doping, or a layer made of a p-type dopant was further inserted between the ITO substrate and the hole transport layer. However, in one embodiment of the present invention, a single hole transport layer made of a compound represented by [Chemical Formula I] or [Chemical Formula II] can be applied without a separate p-type dopant process or insertion.

That is, the compound represented by the above [Chemical Formula I] or [Chemical Formula II] is a multifunctional HTL compound, which means that it has both a hole transport structure and a p-doped structure and moieties having both a hole transport function and a hole injection function, and by using this, by fusing the hole injection function and the hole transport function, it is possible to implement an organic light-emitting device composed of a single hole layer of a multifunctional HTL (Multifunctional Hole Transportation Layer) without forming a hole transport layer and a hole injection layer separately, and can satisfy the low-voltage operation and high-efficiency characteristics of the organic light-emitting device.

In the present invention, examples of the above substituents are specifically described below, but are not limited thereto.

In the present invention, the alkyl group may be linear or branched, and specific examples thereof 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 cyclohectylmethyl group, an octyl group, an n-octyl group, a tert-octyl group, a 1-methylheptyl group, Examples thereof include, but are not limited to, a 2-ethylhexyl group, a 2-propylpentyl group, an n-nonyl group, a 2,2-dimethylheptyl group, a 1-ethyl-propyl group, a 1,1-dimethyl-propyl group, an isohexyl group, a 2-methylpentyl group, a 4-methylhexyl group, and a 5-methylhexyl group.

In the present invention, the alkoxy group may be linear or branched. 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.

In the present invention, the aryl group may be monocyclic or polycyclic. Examples of monocyclic aryl groups include a phenyl group, a biphenyl group, a terphenyl group, a stilbene group, and the like, and examples of polycyclic aryl groups include a naphthyl group, anthracenyl group, a phenanthrenyl group, a pyrenyl group, a perylenyl group, a tetracenyl group, a chrysenyl group, a fluorenyl group, an acenaphthacenyl group, a triphenylene group, a fluoranthrene group, and the like, but the scope of the present invention is not limited to these examples.

In the present invention, the heterocyclic group is a heterocyclic group containing O, N or S as a heteroatom, and is selected from the group consisting of 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 pyrimidyl group, a triazine group, a triazole group, an acridyl group, a pyridazine group, a pyrazinyl group, a quinolinyl group, a quinazoline group, a quinoxalinyl group, a phthalazinyl group, a pyrido pyrimidinyl group, a pyrido pyrazinyl group, a pyrazino pyrazinyl group, an isoquinoline group, an indole group, a carbazole group, a benzoxazole group, a benzimidazole group, a benzothiazole group, a benzocarbazole group, a benzothiophene group, a dibenzothiophene group, a benzofuranyl group, Examples thereof include, but are not limited to, a dibenzofuranyl group, a phenanthroline group, a thiazolyl group, an isoxazolyl group, an oxadiazolyl group, a thiadiazolyl group, a benzothiazolyl group, and a phenothiazinyl group.

In the present invention, the aryl group among the aryloxy group and the arylthioxy group is the same as the examples of the aryl group described above. Specifically, examples of the aryloxy group include a phenoxy group, a p-toryloxy group, a m-toryloxy group, a 3,5-dimethyl-phenoxy group, a 2,4,6-trimethylphenoxy group, a ptert-butylphenoxy group, a 3-biphenyloxy group, a 4-biphenyloxy group, a 1-naphthyloxy group, a 2-naphthyloxy group, a 4-methyl-1-naphthyloxy group, a 5-methyl-2-naphthyloxy group, a 1-anthryloxy group, a 2-anthryloxy group, a 9-anthryloxy group, a 1-phenanthryloxy group, a 3-phenanthryloxy group, a 9-phenanthryloxy group, and the like; examples of the arylthioxy group include a phenylthioxy group, a 2-methylphenylthioxy group, a 4-tert-butylphenylthioxy group, and the like; examples of the arylsulfoxy group include, but are not limited to, a benzenesulfoxy group, a p-toluenesulfoxy group, and the like.

In the present invention, the cycloalkyl group is not particularly limited, and specifically includes, but is not limited to, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a 3-methylcyclopentyl group, a 2,3-dimethylcyclopentyl group, a cyclohexyl group, a 3-methylcyclohexyl group, a 4-methylcyclohexyl group, a 2,3-dimethylcyclohexyl group, a 3,4,5-trimethylcyclohexyl group, a 4-tert-butylcyclohexyl group, a cycloheptyl group, a cyclooctyl group, and the like.

In the present invention, examples of halogen groups include fluorine, chlorine, bromine or iodine.

In the present invention, examples of the arylamine group include a substituted or unsubstituted monoarylamine group, a substituted or unsubstituted diarylamine group, or a substituted or unsubstituted triarylamine group. The aryl group in the arylamine group may be a monocyclic aryl group or a polycyclic aryl group. The arylamine group including two or more aryl groups may include a monocyclic aryl group, a polycyclic aryl group, or a monocyclic aryl group and a polycyclic aryl group at the same time.

Specific examples of the above arylamine group include, but are not limited to, a phenylamine group, a naphthylamine group, a biphenylamine group, an anthracenylamine group, a 3-methyl-phenylamine group, a 4-methyl-naphthylamine group, a 2-methyl-biphenylamine group, a 9-methyl-anthracenylamine group, a diphenyl amine group, a phenyl naphthyl amine group, a ditolyl amine group, a phenyl tolyl amine group, a carbazole group, and a triphenyl amine group.

In the present invention, the silyl group specifically includes, but is not limited to, a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, a vinyldimethylsilyl group, a propyldimethylsilyl group, a triphenylsilyl group, a diphenylsilyl group, a phenylsilyl group, etc.

In the present invention, the heteroaryl group among the heteroarylamine groups can be selected from among the examples of the heterocyclic groups described above.

In the present invention, the alkyl group in the alkylthioxy group is the same as the examples of the alkyl group described above. Specifically, the alkylthioxy group includes a methylthioxy group, an ethylthioxy group, a tert-butylthioxy group, a hexylthioxy group, an octylthioxy group, etc., and the alkylsulfoxy group includes, but is not limited to, a mesyl group, an ethylsulfoxy group, a propylsulfoxy group, a butylsulfoxy group, etc.

The organic light-emitting compound according to the present invention represented by the above [chemical formula I] or [chemical formula II] can be used as an organic layer of an organic light-emitting device due to its structural specificity, and more specifically, the compound itself can be used as a doping material of a hole transport material in the organic layer.

In addition, in the past, in order to control the high conductivity of the hole transport layer formed on the ITO substrate and the charge density of the charge carrier, a p-type dopant was used for doping, or a layer made of a p-type dopant was further inserted between the ITO substrate and the hole transport layer. However, a multifunctional HTL hole transport layer monolayer made of a multifunctional HTL compound represented by the above-mentioned [Chemical Formula I] or [Chemical Formula II] can be implemented without a separate p-type dopant process or insertion.

Preferred specific examples of the doping material or multifunctional HTL compound of the hole transport material represented by [Chemical Formula I] or [Chemical Formula II] according to the present invention include compounds represented by Compounds 1 to 100 below, but are not limited thereto.

The organic light-emitting compound according to the present invention represented by the above [Chemical Formula I] or [Chemical Formula II] can be used as an organic layer of an organic light-emitting device due to its structural specificity, and more specifically, can be used as a p-type doping material, etc., in a hole transport layer or hole injection layer in the organic layer, and according to a preferred embodiment of the present invention, the organic light-emitting compound according to the present invention can be used as a doping material of a hole transport compound of a conventional hole transport layer to implement excellent light-emitting characteristics of the device.

In addition, the organic light-emitting compound according to the present invention is a multifunctional HTL compound having unique characteristics of each introduced substituent by introducing each moiety having a p-doping function and a hole transport characteristic into a single structure, and as a result, a single hole layer of the multifunctional HTL (Multifunctional Hole Transportation Layer) can be implemented, so that an organic light-emitting device having excellent light-emitting characteristics with further improved low-voltage operation characteristics, luminous efficiency, and lifespan characteristics can be implemented.

The compound of the present invention can be applied to a device according to a conventional method for manufacturing an organic light-emitting device.

An organic light-emitting device according to one embodiment of the present invention may have a structure including a first electrode, a second electrode, and an organic layer disposed therebetween, and may be manufactured using a conventional device manufacturing method and materials, except that the organic light-emitting compound according to the present invention is used in the organic layer of the device.

The organic layer of the organic light-emitting device according to the present invention may be formed as a single-layer structure, but may be formed as a multilayer structure in which two or more organic layers are laminated. 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, etc. However, it is not limited thereto and may include a smaller number of organic layers.

Therefore, in the organic light-emitting device of the present invention, the organic layer may include at least one layer from among a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a multi-functional HTL layer (Multi-functional Hole Transportation Layer), a layer that simultaneously injects and transports electrons, and a light-emitting layer, and at least one layer from among the layers may include a compound represented by [Chemical Formula I] or [Chemical Formula II].

In addition, the organic light-emitting device according to the present invention can be formed with a structure including a plurality of organic layers including a first electrode, a second electrode, and an electronic layer, an emission layer, and a hole layer disposed therebetween, and can be manufactured using conventional device manufacturing methods and materials, except that the device is formed by integrating a hole injection function and a hole transport function, without forming a hole transport layer and a hole injection layer separately, and by forming a multifunctional multifunctional HTL layer (Multifunctional Hole Transportation Layer) as a single layer, and without forming a separate p-type layer.

The organic layer of the organic light-emitting device according to the present invention may be formed of a multilayer structure in which two or more organic layers are laminated, except that the hole injection layer and the hole transport layer are formed of a multifunctional HTL single layer, but is not limited thereto and may include a smaller or larger number of organic layers.

The organic layer structure, etc. of the preferred organic light-emitting device according to the present invention will be described in more detail in the examples described below.

The organic light-emitting device according to the present invention is characterized in that the electrical conductivity of the multifunctional HTL is 1 × 10 ^-3 S/m to 1 × 10 ^-1 S/m.

In the organic light-emitting device according to the present invention, the HOMO energy level of the single hole layer composed of the multifunctional HTL, that is, the multifunctional HTL compound, is characterized by being in the range of -4.5 eV to -7.0 eV when expressed on an absolute scale where the vacuum energy level represents 0, and according to one embodiment, the HOMO energy level of the multifunctional HTL can be in the range of -5.0 eV to -6.0 eV when expressed on an absolute scale where the vacuum energy level represents 0.

In the organic light-emitting device according to the present invention, the LUMO energy level of the single hole layer composed of the multifunctional HTL, that is, the multifunctional HTL compound, is characterized by being in the range of -4.0 eV to -6.0 eV when expressed on an absolute scale where the vacuum energy level represents 0, and according to one embodiment, the LUMO energy level of the multifunctional HTL can be in the range of -4.4 eV to -5.5 eV when expressed on an absolute scale where the vacuum energy level represents 0.

The band gap of the multifunctional HTL in the organic light-emitting device according to the present invention is characterized by an absolute value of 2 or less, and according to one embodiment, may be an absolute value of 0.3 to 1.0.

In the organic light-emitting device according to the present invention, the work function of the anode is characterized by being higher than the highest LUMO energy level of a single hole layer composed of a multifunctional HTL, i.e., a multifunctional HTL compound, and having an absolute value of 1 or less, and in one embodiment, may be 0.5 or less.

The multifunctional HTL of the organic light-emitting device according to the present invention can have a thickness of 20 to 1,000 Å, thereby achieving the electrical conductivity properties and voltage drop effect required for the multifunctional HTL, and at the same time, the multifunctional HTL thickness can be increased to 1,000 Å, thereby improving the mechanical properties of the multifunctional HTL.

The organic light-emitting device according to the present invention can be manufactured by forming an anode by depositing a metal or a conductive metal oxide or an alloy thereof on a substrate using a PVD (physical vapor deposition) method such as sputtering or e-beam evaporation, 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.

In addition to this method, an organic light-emitting device can also be manufactured by sequentially depositing a cathode material, an organic layer, and an anode material on a substrate. The organic layer may have a multilayer structure including a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer, but is not limited thereto and may have a single layer structure. In addition, the organic layer can be manufactured with a smaller number of layers by using various polymer materials and a solvent process, such as spin coating, dip coating, doctor blading, screen printing, inkjet printing, or thermal transfer, rather than a deposition method.

As the above anode material, a material having a high work function is generally preferred so that hole injection into the organic layer can be smooth. Specific examples of the anode material that can be used in the present invention include, but are not limited to, metals such as vanadium, chromium, copper, zinc, and gold, or alloys thereof; metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); combinations of metals and oxides such as ZnO:Al or SnO ₂ :Sb; conductive polymers such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDT), polypyrrole, and polyaniline.

As the above cathode material, it is preferable to have a low work function so that electrons can be easily injected into the organic layer. Specific examples of the cathode material include, but are not limited to, 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 LiO ₂ /Al.

The hole injection material is a material that can well inject holes from the anode at a 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 the hole injection material include, but are not limited to, metal porphyrine, oligothiophene, arylamine-series organic compounds, hexanitrile hexaazatriphenylene, quinacridone-series organic compounds, perylene-series organic compounds, anthraquinone, and polyaniline and polythiophene-series conductive polymers.

As a hole transport material, a material with high hole mobility is suitable, as it can transport holes from the anode or hole injection layer and transfer them to the light-emitting layer. Specific examples include, but are not limited to, organic compounds of the arylamine series, conductive polymers, and block copolymers having both conjugated and non-conjugated portions.

The luminescent material is a material that can emit light in the visible range by transporting holes and electrons from the hole transport layer and the electron transport layer respectively and combining them, and a material with good quantum efficiency for fluorescence or phosphorescence is preferable. Specific examples include, but are not limited to, 8-hydroxy-quinoline aluminum complex (Alq ₃ ), carbazole compounds, dimerized styryl compounds, BAlq, 10-hydroxybenzo quinoline-metal compounds, benzoxazole, benzthiazole and benzimidazole compounds, poly(p-phenylenevinylene) (PPV) polymers, spiro compounds, polyfluorene, and rubrene.

As an electron transport material, a material that can easily receive electrons from the cathode and transfer them to the light-emitting layer is suitable, and a material with high electron mobility is suitable. Specific examples include, but are not limited to, Al complexes of 8-hydroxyquinoline, complexes containing Alq ₃ , organic radical compounds, and hydroxyflavone-metal complexes.

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.

In addition, the organic light-emitting compound according to the present invention can function in organic electronic devices including organic solar cells, organic photoconductors, organic transistors, etc., using principles similar to those applied to organic light-emitting devices.

Hereinafter, preferred examples are presented to help understand the present invention. However, the following examples are provided to illustrate the present invention and the scope of the present invention is not limited thereby.

Synthesis Example 1: Synthesis of Compound 4

(1) Manufacturing Example 1: Synthesis of Intermediate 4-1

2,5-dimethoxybenzene-1,4-diol (10 g, 0.059 mol, Mascot.) and 100 mL of acetic acid were added and stirred, then 30 mL of nitric acid was added at room temperature and stirred at 80 ℃ for 0.5 hour to react. After the reaction was completed, the mixture was cooled to room temperature, cold water was added, the resulting solid was filtered, and then column purified to obtain 13 g (85% yield) of <Intermediate 4-1>.

(2) Manufacturing Example 2: Synthesis of Intermediate 4-2

Intermediate 4-1 (10 g, 0.029 mol), Pd/C, 200 mL of EtOH were added, stirred at 0 ℃ using an ice bath under nitrogen, and hydrazine hydrate (6.16 g, 0.192 mol, sigma aldrich) was slowly added dropwise, followed by reflux stirring for 30 minutes to react. After completion of the reaction, extraction was performed, and 6.8 g (yield 88.3%) of <Intermediate 4-2> was obtained through column purification.

(3) Manufacturing Example 3: Synthesis of Intermediate 4-3

Intermediate 4-2 (10 g, 0.05 mol), triethyl orthoformate (74 g, 0.5 mol, sigma aldrich), yttrium(Ⅲ) trifluoromethanesulfonate (1.34 g, 0.0025 mol, sigma aldrich), and 300 mL of DMSO were added and stirred at 60 ℃ for 4 hours to react. After the reaction was completed, extraction was performed and column purification was performed to obtain 8.3 g (yield 75.4%) of <Intermediate 4-3>.

(4) Manufacturing Example 4: Synthesis of Intermediate 4-4

Intermediate 4-1 (10 g, 0.045 mol), tetrabromomethane (33.14 g, 0.1 mol, sigma aldrich), sodium tert-butoxide (34.92 g, 0.363 mol, sigma aldrich) were added to 250 mL of dimethylformamide and stirred at room temperature for 6 hours to react. After completion of the reaction, extraction was performed and column purification was performed to obtain 13 g (yield 75.7%) of <Intermediate 4-4>.

(5) Manufacturing Example 5: Synthesis of Intermediate 4-5

Intermediate 4-4 (10 g, 0.025 mol), phenylboronic acid (7.10 g, 0.058 mol), potassium carbonate (10.97 g, 0.079 mol, sigma aldrich), Pd(PPh ₃ ) ₄ (1.53 g, 0.0013 mol, sigma aldrich), Tol 200 mL, EtOH 40 mL, H ₂ O 20 mL were added and stirred under reflux for 12 hours to react. After the reaction was completed, extraction was performed and column purification was performed to obtain 7 g (yield 71%) of <Intermediate 4-5>.

(6) Manufacturing Example 6: Synthesis of Intermediate 4-6

Intermediate 4-5 (10 g, 0.027 mol) was added with 200 mL of dichloromethane, then borontribromide was added and stirred for 6 hours to react. After the reaction was completed, extraction was performed and column purification was performed to obtain 5 g (yield 54%) of <Intermediate 4-6>.

(7) Manufacturing Example 7: Synthesis of Intermediate 4-7

Intermediate 4-6 (10 g, 0.027 mol), excess MnO ₂ , and 150 mL of methylene chloride were added, stirred under reflux for 24 hours, and reacted. After the reaction was completed, extraction was performed and column purification was performed to obtain 8.4 g (yield 84.4%) of <Intermediate 2-2>.

(8) Manufacturing Example 8: Synthesis of Compound 4

Intermediate 4-7 (10 g, 0.029 mol), malononitrile (11.58 g, 0.175 mol, sigma aldrich), 300 mL of methylene chloride were added and cooled in an ice-bath, then TiCl ₄ (33.25 g, 0.175 mol, sigma aldrich) was slowly dropped and pyridine (20.8 g, 0.263 mol) was added very slowly dropwise. After 1 hour, the ice bath was removed and the mixture was stirred for 24 hours to allow the reaction. After completion of the reaction, the mixture was extracted with an aqueous hydrochloric acid solution and purified by column chromatography to obtain 8.6 g (yield 67.1%) of compound 4.

H-NMR (200MHz, CDCl3):δppm, 2H(7.41/m) 4H(8.05/d, 7.51/d)

LC/MS: m/z=438[(M+1) ⁺ ]

Synthesis Example 2: Synthesis of Compound 20

(1) Manufacturing Example 1: Synthesis of Intermediate 20-1

Gallium trichloride (0.51 g, 0.0029 mol, sigma aldrich) was added to 150 mL of 1,2-dichloroethane, and intermediate 4-6 (10 g, 0.029 mol) and cyanic bromide (6.77 g, 0.064 mol, sigma aldrich) were added. The mixture was stirred at 120 ℃ for 5 hours to react. After the reaction was completed, extraction was performed and column purification was performed to obtain 5.8 g (yield 55.1%) of <Intermediate 20-1>.

(2) Manufacturing Example 2: Synthesis of Intermediate 20-2

Intermediate 20-1 (10 g, 0.028 mol) was added to 150 mL of dichloromethane, cooled to -78 ℃, DIBAL (1.0 M in THF) was slowly added dropwise, stirred for 1 hour, and then stirred at room temperature for 1 hour. After cooling to 0 ℃, acetic acid and _H2O were added, extracted, and column purified to obtain 7.5 g (yield 73.8%) of <Intermediate 20-2>.

(3) Manufacturing Example 3: Synthesis of Intermediate 20-3

Intermediate 20-2 (10 g, 0.027 mol), oxalaldehyde (3.94 g, 0.068 mol, sigma aldrich), ammonium acetate (12.56 g, 0.163 mol, sigma aldrich), and acetic acid (250 mL) were added and stirred at 110 ℃ for 12 hours to react. After completion of the reaction, ice _H2O was added, extraction was performed, and column purification was performed to obtain 6 g (yield 49.7%) of <Intermediate 20-3>.

(4) Manufacturing Example 4: Synthesis of Intermediate 20-4

Intermediate 20-3 (10 g, 0.0225 mol) and 300 mL of THF were added, cooled to 0°C, N -bromosuccinimide (16.02 g, 0.090 mol, sigma aldrich) was slowly added, and the mixture was stirred at room temperature for 5 hours to react. After the reaction was completed, extraction and purification were performed to obtain 13.3 g (yield 77.7%) of <Intermediate 20-4>.

(5) Manufacturing Example 5: Synthesis of Intermediate 20-5

Intermediate 20-4 (10 g, 0.013 mol), CuCN (11.78 g, 0.132 mol, sigma aldrich), and 250 mL of DMF were added and stirred under reflux for 8 hours to react. After the reaction was completed, extraction and purification were performed to obtain 3.5 g (yield 48.8%) of <Intermediate 20-5>.

(6) Manufacturing Example 6: Synthesis of Intermediate 20-6

Intermediate 20-5 (10 g, 0.018 mol), potassium hydroxide (10.31 g, 0.184 mol) H ₂ O 20 mL, 1,4-dioxane 400 mL were added, and K ₃ Fe(CN) ₆ (42.33 g, 0.129 mol) solution (H ₂ O 420 mL) was added dropwise, and stirred for 12 hours at 100 ℃ to react. After completion of the reaction, extraction was performed and column purification was performed to obtain 3.8 g (yield 38.1%) of compound 20.

H-NMR (200MHz, CDCl3):δppm, 2H (7.41/m) 4H (8.05/d, 7.51/m)

LC/MS: m/z=542[(M+1) ⁺ ]

Synthesis Example 3: Synthesis of Compound 58

(1) Manufacturing Example 1: Synthesis of Intermediate 58-1

1,4-difluoro-2,5-dimethoxybenzene (10 g, 0.057 mol, sigma aldrich) and 300 mL of dimethyl chloride were added, cooled to 0 ℃, bromine was slowly added dropwise, and stirred at room temperature for 5 hours to react. After the reaction was completed, extraction and purification were performed to obtain 14 g (yield 73.4%) of <Intermediate 58-1>.

(2) Manufacturing Example 2: Synthesis of Intermediate 58-2

Intermediate 58-1 (10 g, 0.030 mol), 2-hydroxyphenylboronic acid (9.14 g, 0.066 mol, sigma aldrich), potassium carbonate (20.82 g, 0.151 mol, sigma aldrich), Pd(PPh ₃ ) ₄ (1.74 g, 0.0015 mol, sigma aldrich), 250 mL of Tol, 50 mL of EtOH, and 30 mL of H ₂ O were added and stirred under reflux for 12 hours to react. After the reaction was completed, extraction was performed and column purification was performed to obtain 8 g (yield 74.1%) of <Intermediate 58-2>.

(3) Manufacturing Example 3: Synthesis of Intermediate 58-3

Intermediate 58-2 (10 g, 0.046 mol), potassium carbonate (11.57 g, 0.084 mol, sigma aldrich), DMAP (0.34 g, 0.0028 mol, sigma aldrich), and 300 mL of DMF were added and stirred under reflux for 3 hours at 160 ℃ to react. After the reaction was completed, extraction was performed and column purification was performed to obtain 7.3 g (yield 82.1%) of <Intermediate 58-3>.

(4) Manufacturing Example 4: Synthesis of Intermediate 58-4

Intermediate 4-5 (10 g, 0.031 mol) was added with 200 mL of dichloromethane, then borontribromide was added and stirred for 6 hours to react. After the reaction was completed, extraction was performed and column purification was performed to obtain 5 g (yield 54%) of <Intermediate 58-4>.

(5) Manufacturing Example 5: Synthesis of Intermediate 58-5

Gallium trichloride (0.61 g, 0.0029 mol, sigma aldrich) was added to 150 mL of 1,2-dichloroethane, and intermediate 4-6 (10 g, 0.035 mol) and cyanic bromide (8.03 g, 0.076 mol, sigma aldrich) were added. The mixture was stirred at 120 ℃ for 5 hours to react. After the reaction was completed, extraction was performed and column purification was performed to obtain 6 g (yield 56.4%) of <intermediate 58-5>.

(6) Manufacturing Example 6: Synthesis of Intermediate 58-6

Intermediate 20-1 (10 g, 0.032 mol) was added to 150 mL of dichloromethane, cooled to -78 ℃, DIBAL (1.0 M in THF) was slowly added dropwise, stirred for 1 hour, and then stirred at room temperature for 1 hour. After cooling to 0 ℃, acetic acid and _H2O were added, extracted, and column purified to obtain 7.6 g (yield 74.5%) of <Intermediate 58-6>.

(7) Manufacturing Example 7: Synthesis of Intermediate 58-7

Intermediate 58-6 (10 g, 0.032 mol), 1,1,1,4,4,4-hexafluorobutane-2,3-dione (15.43 g, 0.080 mol, Mascot.), ammonium acetate (14.72 g, 0.191 mol, sigma aldrich), and acetic acid 250 mL were added and stirred at 110 ℃ for 12 hours to react. After completion of the reaction, ice _H2O was added, extraction was performed, and column purification was performed to obtain 11.6 g (yield 55%) of <Intermediate 58-7>.

(8) Manufacturing Example 8: Synthesis of compound 58

Intermediate 58-7 (10 g, 0.015 mol), potassium hydroxide (8.47 g, 0.151 mol) H ₂ O 25 mL, 1,4-dioxane 500 mL were added, and K ₃ Fe(CN) ₆ (34.79 g, 0.106 mol) solution (H ₂ O 350 mL) was added dropwise, stirred and reacted at 100 ℃ for 12 hours. After the reaction was completed, extraction was performed and column purification was performed to obtain 4 g (yield 40%) of compound 58.

H-NMR (200MHz, CDCl3):δppm, 2H(7.89/d, 7.66/d, 7.38/m, 7.32/m)

LC/MS: m/z=660[(M+1) ⁺ ]

Synthesis Example 4: Synthesis of Compound 98

(1) Manufacturing Example 1: Synthesis of Intermediate 98-1

Toluene (300 mL) was added bromobenzene (10 g, 0.064 mol, sigma aldrich), 2-naphthylamine (10.94 g, 0.076 mol, sigma aldrich), sodium tert-butoxide (12.24 g, 0.13 mol, sigma aldrich), catalyst Pd(dba) ₂ (1.83 g, 0.0032 mol, sigma aldrich), tri-tert-Bu-phosphine (1.24 g, 0.0064 mol, sigma aldrich), and the mixture was stirred at 100 ℃ for 4 hours to react. After completion of the reaction, extraction was performed and column purification was performed to obtain 18 g (yield 71.6%) of <Intermediate 98-1>.

(2) Manufacturing Example 2: Synthesis of Intermediate 98-2

Toluene (300 mL) was added bromobenzene (10 g, 0.064 mol, sigma aldrich), 2-aminobiphenyl (12.93 g, 0.076 mol, sigma aldrich), sodium tert-butoxide (12.24 g, 0.13 mol, sigma aldrich), catalyst Pd(dba) ₂ (1.83 g, 0.0032 mol, sigma aldrich), tri-tert-Bu-phosphine (1.24 g, 0.0064 mol, sigma aldrich), and the mixture was stirred at 100 ℃ for 4 hours to react. After completion of the reaction, extraction was performed and column purification was performed to obtain 11.7 g (yield 74.8%) of <Intermediate 98-2>.

(3) Manufacturing Example 3: Synthesis of Intermediate 98-3

Intermediate 98-1 (10 g, 0.046 mol), intermediate 4-4 (12.93 g, 0.058 mol), sodium tert-butoxide (8.77 g, 0.055 mol, sigma aldrich), catalyst Pd(dba) ₂ (1.31 g, 0.091 mol, sigma aldrich), tri-tert-Bu-phosphine (1.31 g, 0.0046 mol, sigma aldrich) were added to 300 mL of toluene and stirred at 100 ℃ for 4 hours to allow reaction. After completion of the reaction, extraction was performed and column purification was performed to obtain 7.2 g (yield 52.7%) of <Intermediate 98-3>.

(4) Manufacturing Example 4: Synthesis of Intermediate 98-4

Intermediate 98-3 (10 g, 0.019 mol), intermediate 98-2 (5.70 g, 0.023 mol), sodium tert-butoxide (8.77 g, 0.055 mol, sigma aldrich), catalyst Pd(dba) ₂ (0.56 g, 0.001 mol, sigma aldrich), tri-tert-Bu-phosphine (0.39 g, 0.0019 mol, sigma aldrich) were added to 300 mL of toluene and stirred at 100 ℃ for 6 hours to react. After the reaction was completed, extraction was performed and column purification was performed to obtain 10 g (yield 75.8%) of <Intermediate 98-4>.

(5) Manufacturing Example 5: Synthesis of Intermediate 98-5

Intermediate 98-4 (10 g, 0.015 mol) was added 200 mL of dichloromethane, borontribromide was added, and stirred for 6 hours to react. After the reaction was completed, extraction was performed and column purification was performed to obtain 4.8 g (50% yield) of <Intermediate 98-5>.

(6) Manufacturing Example 6: Synthesis of Intermediate 98-6

Intermediate 98-5 (10 g, 0.015 mol), excess MnO ₂ , and 150 mL of methylene chloride were added, stirred under reflux for 24 hours, and reacted. After the reaction was completed, extraction was performed and column purification was performed to obtain 8.7 g (yield 87.28%) of <Intermediate 98-6>.

(7) Manufacturing Example 7: Synthesis of Intermediate 98-7

Intermediate 4-7 (10 g, 0.015 mol), malononitrile (3.05 g, 0.046 mol, sigma aldrich), 300 mL of methylene chloride were added and cooled in an ice-bath, then TiCl ₄ (8.75 g, 0.046 mol, sigma aldrich) was slowly dropped and pyridine (4.86 g, 0.062 mol) was added very slowly dropwise. After 1 hour, the ice bath was removed and the mixture was stirred for 24 hours to react. After completion of the reaction, extraction was performed with an aqueous hydrochloric acid solution and column purification was performed to obtain 6.1 g (yield 61.4%) of <Intermediate 98-7>.

(8) Manufacturing Example 8: Synthesis of Compound 98

Intermediate 98-7 (10 g, 0.014 mol), bis(3-fluorophenyl)methane (8.77 g, 0.043 mol), and 300 mL of methylene chloride were added and cooled in an ice-bath, then TiCl ₄ (8.14 g, 0.043 mol, Sigma Aldrich) was slowly dropped and pyridine (4.53 g, 0.057 mol) was added very slowly dropwise. After 1 hour, the ice bath was removed and the mixture was stirred for 24 hours and reacted. After completion of the reaction, extraction was performed with an aqueous hydrochloric acid solution and column purification was performed to obtain 7.7 g (yield 60.8%) of compound 98.

H-NMR (200MHz, CDCl3):δppm, 1H(7.88/d, 7.84/d, 7.77/d, 7.74/s, 7.50/m, 7.49/d, 7.41/m, 7.36/m) 2H(7.54/d, 7.52/d, 7.51/m, 7.26/m, 7.15/d, 7.12/d, 6.96/d, 6.81/m, 6.69/s) 4H (7.20/m, 6.63/d)

LC/MS: m/z=884[(M+1) ⁺ ]

Element Example

In an embodiment according to the present invention, an ITO transparent electrode was patterned on a glass substrate measuring 25 mm × 25 mm × 0.7 mm to have a light-emitting area of 2 mm × 2 mm using an ITO glass substrate having an ITO transparent electrode attached thereto, and then cleaned. After mounting the substrate in a vacuum chamber, the base pressure was made 1 × 10 ^-6 torr, and then an organic material and a metal were deposited on the ITO with the following structure.

Element Examples 1 to 10

A blue light-emitting organic electroluminescent device having the following device structure was manufactured by employing a multifunctional HTL compound according to the present invention as a material for a multifunctional HTL hole layer according to the present invention, and the light-emitting characteristics including light-emitting efficiency were measured.

ITO / Multifunctional HTL hole layer (100 nm) / Electron blocking layer (10 nm) / Emitting layer (20 nm) / Electron transport layer (201:Liq 30 nm) / LiF (1 nm) / Al (100 nm)

A hole layer was formed on an ITO transparent electrode using the multifunctional HTL compounds 61, 65, 72, 75, 83, 89, and 91 according to the present invention. The hole blocking layer was formed with a thickness of 10 nm using [EBL1]. In addition, the emitting layer was formed with a thickness of about 20 nm using [BH1] as a host compound and [BD1] as a dopant compound, and additionally, 30 nm of an electron transport layer (doped with 50% Liq of the following [201] compound), 1 nm of LiF, and 100 nm of aluminum were formed by a vapor deposition method to manufacture an organic light-emitting device.

Comparison Example 1 of Components

An organic light-emitting device for Comparative Example 1 was manufactured in the same manner as in Example 1 except that the hole layer was replaced with the compound according to the present invention and 5% F4TCNQ was doped into α-NPB.

Comparison Example 2 of Components

An organic light-emitting device for comparative example 2 was manufactured in the same manner as in Example 1 except that α-NPB was used instead of the compound according to the present invention for the hole layer.

Experimental Example 1: Luminescence characteristics of device examples 1 to 10

The organic light emitting diodes manufactured according to the above examples were measured for voltage, current, and luminous efficiency using a source meter (Model 237, Keithley) and a luminance meter (PR-650, Photo Research), and the voltage at which the luminance reached 1000 nit was defined as the “driving voltage” and compared. The results are shown in [Table 1] below.

Example Multifunctional HTL V cd/A CIEx CIEy 1 Compound 61 4.8 8.29 0.145 0.142 2 Compound 65 4.8 8.12 0.144 0.142 3 Compound 72 4.8 8.20 0.145 0.143 4 Compound 75 4.9 7.92 0.145 0.148 5 Compound 83 4.9 8.06 0.144 0.151 6 Compound 89 5.0 8.13 0.145 0.146 7 Compound 91 4.9 7.86 0.145 0.152 8 Compound 93 4.9 7.97 0.145 0.153 9 Compound 97 4.9 8.41 0.145 0.152 10 Compound 98 5.0 8.25 0.144 0.150 Comparative Example 1 α-NPB: F4TCNQ 5.7 6.84 0.145 0.146 Comparative Example 2 α-NPB 6.2 6.20 0.148 0.155

Looking at the results shown in the above [Table 1], it can be confirmed that when the compound according to the present invention is applied alone to the multifunctional HTL layer (Multi-functional Hole Transportation Layer) of the device, the luminescence characteristics such as luminescence efficiency and quantum efficiency are significantly superior compared to the conventional device (comparative example) even though separate doping was not performed.

[α-NPB] [EBL1] [BH1] [BD1] [201] [F4TCNQ]

P-doped device example

In an embodiment according to the present invention, an ITO transparent electrode was patterned on a glass substrate measuring 25 mm × 25 mm × 0.7 mm to have a light-emitting area of 2 mm × 2 mm using an ITO glass substrate having an ITO transparent electrode attached thereto, and then cleaned. After mounting the substrate in a vacuum chamber, the base pressure was made 1 × 10 ^-6 torr, and then an organic material and a metal were deposited on the ITO with the following structure.

Element Examples 11 to 16

A blue light-emitting organic electroluminescent device having the following device structure was manufactured using the compound according to the present invention as a doping compound for a hole transport material, and the light-emitting characteristics including the light-emitting efficiency were measured.

ITO / Hole injection layer (5 nm) / Hole transport layer (100 nm) / Electron blocking layer (10 nm) / Emitting layer (20 nm) / Electron transport layer (201:Liq 30 nm) / LiF (1 nm) / Al (100 nm)

The compounds 4, 20, 46, 58, 60, and 95 according to the present invention were deposited as a 5 nm thick film on a hole injection layer on an ITO transparent electrode, and the hole transport layer was deposited as a 100 nm thick film using α-NPB. At this time, the hole blocking layer was deposited as a 10 nm thick film using [EBL1]. In addition, the emitting layer was deposited as a host compound using [BH1] and as a dopant compound using [BD1] to a thickness of about 20 nm, and additionally, an electron transport layer (doped with 50% Liq of the following [201] compound), 1 nm of LiF, and 100 nm of aluminum were deposited as films by a vapor deposition method, to manufacture an organic light-emitting device.

Comparison Example 3 of Components

The organic light-emitting device for Comparative Example 3 was manufactured in the same manner as in Example 11 except that HAT-CN was used as the hole injection layer material.

Experimental Example 2: Luminescence characteristics of device examples 11 to 16

The organic light-emitting device manufactured according to the above example was measured for voltage, current, and luminous efficiency using a source meter (Model 237, Keithley) and a luminance meter (PR-650, Photo Research), and the voltage at which the luminance reached 1000 nit was defined as the “driving voltage” and compared. The results are shown in [Table 2] below.

Example P-doping agent V cd/A QE(%) CIEx CIEy 11 Compound 4 4.70 8.24 7.65 0.145 0.153 12 Compound 20 4.75 8.27 7.69 0.145 0.153 13 Compound 46 4.80 8.33 7.73 0.145 0.152 14 Compound 58 4.85 8.25 7.67 0.145 0.152 15 Compound 60 4.90 8.29 7.71 0.145 0.152 16 Compound 95 4.95 8.30 7.72 0.146 0.153 Comparative Example 3 HAT-CN 5.40 7.5 6.1 0.147 0.156

Looking at the results shown in the above [Table 2], it can be confirmed that when the compound according to the present invention is applied to a device as a hole injection layer material, the luminescence characteristics such as luminescence efficiency and quantum efficiency are significantly superior to when HAT-CN is used compared to a conventional device (comparative example).

[α-NPB]

[HAT-CN] [EBL1] [BH1] [BD1] [201]

Claims (11)

An organic luminescent compound represented by the following [chemical formula I] or [chemical formula II]:
[Chemical Formula I]

In the above [chemical formula I],
X ₁ is any one selected from O, S, R ₁₃ -CR ₁₄ , R ₁₅ -Si-R ₁₆ and NR ₁₇ ,
X ₂ is N,
A and B are the same or different from each other and are each independently selected from [structural formula 1a] to [structural formula 1d],
[Structural formula 1a] [Structural formula 1b] [Structural formula 1c]

[Structural formula 1d]

In the above [structural formula 1a] to [structural formula 1d],
R ₁ to R ₄ are each independently any one selected from a halogen group, a cyano group, a nitro group, a sulfonyl group (SO ₂ R'), a sulfoxide group (SO ₃ ), a carbonyl group (COR'), a carboxyl group (CO ₂ R'), a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, and a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms,
The above R' is any one selected from hydrogen, deuterium, a cyano group, a halogen group, an amino group, a thiol group, a hydroxy group, a nitro group, an alkyl group having 1 to 24 carbon atoms, a halogenated alkyl group having 1 to 24 carbon atoms, an alkenyl group having 2 to 24 carbon atoms, an aryl group having 6 to 24 carbon atoms, a heteroaryl group having 2 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, an alkylsilyl group having 1 to 24 carbon atoms, and an arylsilyl group having 1 to 24 carbon atoms,
R is any one selected from a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted arylamine group having 6 to 50 carbon atoms, and a substituted or unsubstituted heteroarylamine group having 3 to 50 carbon atoms,
R ₁₃ to R ₁₇ are each independently selected from hydrogen, deuterium, a halogen group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted arylamine group having 6 to 50 carbon atoms, and a substituted or unsubstituted heteroarylamine group having 3 to 50 carbon atoms.

[Chemical Formula II]

In the above [chemical formula II],
X ₃ and X ₄ are each independently one selected from O, S, R ₂₀ -CR ₂₁ , R ₂₂ -Si-R ₂₃ and NR ₂₄ ,
A and B are the same or different from each other and are each independently selected from [structural formula 1a] to [structural formula 1d] (excluding the case where both A and B are [structural formula 1a] below),
[Structural formula 1a] [Structural formula 1b] [Structural formula 1c]

[Structural formula 1d]

In the above [structural formula 1a] to [structural formula 1d],
R ₁ to R ₄ are each independently any one selected from a halogen group, a cyano group, a nitro group, a sulfonyl group (SO ₂ R'), a sulfoxide group (SO ₃ ), a carbonyl group (COR'), a carboxyl group (CO ₂ R'), a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, and a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms,
The above R' is selected from hydrogen, deuterium, a cyano group, a halogen group, an amino group, a thiol group, a hydroxy group, a nitro group, an alkyl group having 1 to 24 carbon atoms, a halogenated alkyl group having 1 to 24 carbon atoms, an alkenyl group having 2 to 24 carbon atoms, an aryl group having 6 to 24 carbon atoms, a heteroaryl group having 2 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, an alkylsilyl group having 1 to 24 carbon atoms, and an arylsilyl group having 1 to 24 carbon atoms,
R is any one selected from hydrogen, deuterium, a cyano group, a halogen group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted arylamine group having 6 to 50 carbon atoms, and a substituted or unsubstituted heteroarylamine group having 3 to 50 carbon atoms,
R ₅ to R ₁₂ and R ₂₀ to R ₂₄ are each independently any one selected from hydrogen, deuterium, a halogen group, a cyano group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted arylamine group having 6 to 50 carbon atoms, and a substituted or unsubstituted heteroarylamine group having 3 to 50 carbon atoms. In the first paragraph,
An organic light-emitting compound characterized in that in the above [chemical formula Ⅰ], two R are the same or different and are each selected from the following [structural formula 2] and [structural formula 3]:
[Structural formula 2]

[Structural formula 3]

In the above [structural formula 2] and [structural formula 3],
L ₁ and L ₂ are each a single bond or are selected from a substituted or unsubstituted arylene group having 6 to 30 carbon atoms and a substituted or unsubstituted heteroarylene group having 2 to 30 carbon atoms, n and m are each an integer of 0 to 4, and when n and m are each 2 or more, a plurality of L ₁ and L ₂ are each the same as or different from each other,
Ar ₁ to Ar ₃ are the same or different from each other, and are each independently selected from a substituted or unsubstituted aryl group having 5 to 50 carbon atoms and a substituted or unsubstituted heteroaryl group having 2 to 50 carbon atoms,
The above Ar ₁ and Ar ₂ may be bonded to each other or connected to adjacent substituents to form an alicyclic or aromatic monocyclic or polycyclic ring, and the carbon atoms of the formed alicyclic or aromatic monocyclic or polycyclic ring may be substituted with at least one heteroatom selected from N, S and O,
o, p and q are each integers from 1 to 3, and when o, p and q are each 2 or greater, a plurality of Ar ₁ to Ar ₃ are each the same or different from each other. In the second paragraph,
An organic light-emitting compound characterized in that in the above [chemical formula Ⅰ], two R are the same or different and are each represented by the above [structural formula 2]. In the first paragraph,
An organic light-emitting compound characterized in that at least one of R ₅ to R ₈ in the above [Chemical Formula II] and at least one of R ₉ to R ₁₂ are the same as or different from each other and are each selected from the following [Structural Formula 2] and [Structural Formula 3]:
[Structural formula 2]

[Structural formula 3]

In the above [structural formula 2] and [structural formula 3],
L ₁ and L ₂ are each a single bond or are selected from a substituted or unsubstituted arylene group having 6 to 30 carbon atoms and a substituted or unsubstituted heteroarylene group having 2 to 30 carbon atoms, n and m are each an integer of 0 to 4, and when n and m are each 2 or more, a plurality of L ₁ and L ₂ are each the same as or different from each other,
Ar ₁ to Ar ₃ are the same or different from each other, and are each independently selected from a substituted or unsubstituted aryl group having 5 to 50 carbon atoms and a substituted or unsubstituted heteroaryl group having 2 to 50 carbon atoms,
The above Ar ₁ and Ar ₂ may be bonded to each other or connected to adjacent substituents to form an alicyclic or aromatic monocyclic or polycyclic ring, and the carbon atoms of the formed alicyclic or aromatic monocyclic or polycyclic ring may be substituted with at least one heteroatom selected from N, S and O,
o, p and q are each integers from 1 to 3, and when o, p and q are each 2 or greater, a plurality of Ar ₁ to Ar ₃ are each the same or different from each other. In paragraph 4,
An organic light-emitting compound characterized in that at least one of R ₅ to R ₈ in the above [Chemical Formula II] and at least one of R ₉ to R ₁₂ are the same as or different from each other and are each represented by the following [Structural Formula 2]. In the first paragraph,
The compound represented by the above [chemical formula I] or [chemical formula II] is an organic light-emitting compound characterized in that it is selected from compounds represented by the following chemical formulas:

An organic light-emitting device comprising a first electrode, a second electrode, and at least one organic layer disposed between the first electrode and the second electrode,
An organic light-emitting device characterized in that at least one of the organic layers comprises one compound selected from the compounds represented by [Chemical Formula I] or [Chemical Formula II] according to claim 1. In Article 7,
The above organic layer includes at least one of a hole injection layer, a hole transport layer, a multi-functional HTL layer, an electron transport layer, an electron injection layer, a layer that simultaneously transports and injects electrons, and a light-emitting layer.
An organic light-emitting device characterized in that at least one of the above layers comprises one compound selected from the compounds represented by [Chemical Formula I] or [Chemical Formula II]. In Article 8,
The above hole injection layer or hole transport layer comprises one compound selected from the compounds represented by [Chemical Formula I] or [Chemical Formula II],
An organic light-emitting device characterized in that the above compound is a p-type doping material. In Article 8,
The above multifunctional HTL layer (Multi-functional Hole Transportation Layer) comprises one compound selected from the compounds represented by [Chemical Formula I] or [Chemical Formula II],
An organic light-emitting device characterized in that the compound is a compound that combines hole injection and hole transport functions, including a hole transportation unit and a p-dopant unit. In Article 8,
An organic light-emitting device characterized in that the above multifunctional HTL layer (Multi-functional Hole Transportation Layer) is composed of a single layer, is formed without a p-dopant doping process, and is composed of an organic light-emitting compound represented by [Chemical Formula I] or [Chemical Formula II].