KR20210001240A - Organic electroluminescent device - Google Patents

Abstract

The present invention may provide an organic electroluminescent device comprising an organic functional layer which is provided between a hole transport auxiliary layer and a light emitting layer, wherein the organic functional layer is obtained by mixing and co-depositing the material of the corresponding hole transport auxiliary layer and the material of the corresponding light emitting layer, thereby exhibiting high luminous efficiency, low driving voltage, long service life, and the like.

Description

Organic electroluminescent device {ORGANIC ELECTROLUMINESCENT DEVICE}

The present invention is an organic electroluminescent device that simultaneously exhibits high luminous efficiency, low driving voltage, and long life, by separately providing an organic functional layer in which the hole transport auxiliary layer material and the light emitting layer material are mixed between the hole transport auxiliary layer and the light emitting layer. Can provide.

In 1965, research on an organic electroluminescent (EL) device (hereinafter simply referred to as'organic EL device') followed by blue electroluminescence using an anthracene single crystal (hereinafter, simply referred to as'organic EL device') was continued, and in 1987 the hole layer was formed by Tang. An organic EL device having a two-layer stack structure composed of (NPB) and a light emitting layer (Alq ₃ ) has been proposed. Afterwards, the organic EL device induces electroluminescence to occur by the combination of holes and electrons, an organic layer in charge of hole injection and transport, an organic layer in charge of electron injection and transport in the device in order to realize the high efficiency and long life characteristics required for commercialization. A form of a multi-layered structure with each characteristic and subdivided function, such as an organic layer, has been proposed. The introduction of a multi-layered structure improves the performance of organic EL devices to the commercialization characteristics, and is trying to expand its application range to portable information display devices and TV display devices, starting with radio display products for vehicles in 1997.

The demand for an increase in the size and resolution of a display places the problem of increasing the efficiency and longevity of organic EL devices. In particular, in the case of higher resolution realized through the formation of more pixels in the same area, it results in a reduction in the emission area of the organic EL pixels, which inevitably reduces the lifespan, and the most important technical problem that the organic EL device must overcome is Became.

In the organic EL device, when a current or voltage is applied to two electrodes, holes are injected into the organic material layer from the anode and electrons are injected into the organic material layer from the cathode. When the injected holes and electrons meet, excitons are formed, and these excitons fall to the ground state to emit light. In this case, the organic EL device may be classified into a fluorescent EL device in which singlet excitons contribute to light emission and a phosphorescent EL device in which triplet excitons contribute to light emission according to the type of electron spin of the formed excitons.

The electron spin of excitons, which is formed by recombination of electrons and holes, generates singlet excitons and triplet excitons at a rate of 25% and 75%. Fluorescent EL devices that emit light by singlet excitons theoretically cannot exceed 25% of the internal quantum efficiency depending on the generation rate, and 5% of the external quantum efficiency is accepted as a limit. Phosphorescent EL devices that emit light by triplet excitons improve luminous efficiency up to 4 times compared to fluorescence when a metal complex compound containing heavy atoms of transition metals such as Ir and Pt is used as a phosphorescent dopant. I can make it.

As described above, phosphorescent EL devices exhibit higher luminous efficiency than fluorescence in terms of luminous efficiency based on theoretical facts, but in blue phosphorescent devices excluding green and red, a phosphorescent dopant with deep blue color purity and high efficiency and a wide energy satisfying the same Blue phosphorescent devices have not yet been commercialized due to insufficient development level for Gap hosts, and blue phosphorescent devices are being used in products.

In order to improve the characteristics of the organic EL device described above, research results have been reported for increasing the stability of the device by preventing holes from diffusing into the electron transport layer. However, to date, satisfactory results have not been obtained.

The present invention was devised to solve the above problems, and by separately providing an organic functional layer in which a hole transport auxiliary layer material and a light emitting layer material are mixed in a predetermined ratio between the hole transport auxiliary layer and the light emitting layer, high efficiency, low voltage and long life are achieved. It is an object of the present invention to provide an organic EL device exhibited at the same time.

In order to achieve the above object, the present invention is a positive electrode; Hole transport area; Light-emitting layer; It has a structure in which an electron transport region and a cathode are sequentially stacked, the hole transport region includes a hole injection layer, a hole transport layer, and a hole transport auxiliary layer, and at least one disposed between the hole transport auxiliary layer and the light emitting layer Further comprising an organic functional layer, wherein the organic functional layer, the material of the light emitting layer; And it provides an organic electroluminescent device comprising a mixture of the material of the hole transport auxiliary layer.

In one embodiment of the present invention, the HOMO (highest occupied molecular orbital, HOMO) energy level of the hole transport auxiliary layer may be higher than the HOMO energy level of the hole transport layer and lower than the HOMO energy level of the light emitting layer.

In one embodiment of the present invention, the difference between the HOMO energy level of the hole transport auxiliary layer and the HOMO energy level of the hole transport layer may be greater than 0 eV and less than 1.0 eV.

In one embodiment of the present invention, the difference between the HOMO energy level of the hole transport auxiliary layer and the HOMO energy level of the light emitting layer is higher than the difference between the HOMO energy level of the hole transport auxiliary layer and the hole transport layer, and may be 1.0 eV or less. .

In one embodiment of the present invention, the LUMO (lowest unoccupied molecular orbital, LUMO) energy level of the hole transport auxiliary layer may be less than the LUMO energy level of the emission layer.

In one embodiment of the present invention, a difference between the LUMO energy level of the hole transport auxiliary layer and the LUMO energy level of the light emitting layer may be greater than 0 eV and less than or equal to 1.0 eV.

In one embodiment of the present invention, the triplet energy (T1) of the hole transport auxiliary layer may be 2.0 eV or more.

In one embodiment of the present invention, the organic functional layer is a material of the auxiliary hole transport layer; And it may be formed by co-deposition (co-deposition) the material of the light emitting layer.

In one embodiment of the present invention, the organic functional layer includes a compound of Formula 1 contained in the hole transport auxiliary layer, a host material and a dopant material contained in the light-emitting layer, wherein the compound of Formula 1 and the The mixing ratio of the host material is 5 to 95: 95 to 5 weight ratio, and the dopant material may be included in an amount of 0.5 to 30 parts by weight based on the total weight of the compound of Formula 1 and the host material.

In one embodiment of the present invention, the electron transport region may include at least one of an electron transport auxiliary layer, an electron transport layer, and an electron injection layer.

In the present invention, an organic electroluminescent device having a low driving voltage and high luminous efficiency can be provided by disposing an organic functional layer in which these materials are mixed in a predetermined ratio between the hole transport auxiliary layer and the light emitting layer. In addition, by applying the organic electroluminescent device of the present invention to a display panel, it is possible to provide a display panel with improved performance and lifespan.

The effects according to the present invention are not limited by the contents exemplified above, and more various effects are included in the present specification.

1 is a cross-sectional view showing the structure of an organic electroluminescent device according to an embodiment of the present invention.
2 is a cross-sectional view showing the structure of an organic electroluminescent device according to another embodiment of the present invention.
FIG. 3 is a graph showing the relationship of the highest occupied molecular orbital (HOMO) energy level between a hole transport layer, a hole transport auxiliary layer, and a light emitting layer according to an embodiment of the present invention.
4 is a graph showing a relationship between a lower unoccupied molecular orbital (LUMO) energy level between a hole transport auxiliary layer and a light emitting layer according to an embodiment of the present invention.
<Simple explanation of sign>
100, 200: organic electroluminescent element A, A': organic layer
10: anode 20: cathode
30: hole transport area 31: hole injection layer
32: hole transport layer 33: hole transport auxiliary layer
40: light emitting layer 50: electron transport region
51: electron transport layer 52: electron injection layer
53: electron transport auxiliary layer 60: organic functional layer

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms different from each other, and only these embodiments make the disclosure of the present invention complete, and common knowledge in the technical field to which the present invention pertains. It is provided to completely inform the scope of the invention to those who have it, and the invention is only defined by the scope of the claims. Accordingly, in some embodiments, well-known process steps, well-known device structures, and well-known techniques have not been described in detail in order to avoid obscuring interpretation of the present invention. The same reference numerals refer to the same components throughout the specification.

Unless otherwise defined, all terms (including technical and scientific terms) used in the present specification may be used as meanings that can be commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not interpreted ideally or excessively unless explicitly defined specifically.

<Organic EL device>

An organic electroluminescent device according to an embodiment of the present invention includes: an anode; A negative electrode disposed opposite to the positive electrode; And one or more organic material layers interposed between the anode and the cathode and including a hole transport region, a light emitting layer, and an electron transport region, and between the auxiliary hole transport layer and the light emitting layer included in the hole transport region. The material of the mixture includes an organic functional layer mixed with each other.

Since these organic functional layers are co-depositioned by mixing two adjacent organic material layers, that is, the material of the hole transport auxiliary layer and the material of the light emitting layer, hole transport due to the barrier-free effect of the use of the same material. Holes injected from the auxiliary layer can be smoothly supplied to the emission layer, thereby improving the luminous efficiency of the organic electroluminescent device and significantly improving the lifetime characteristics.

Hereinafter, preferred embodiments of the organic electroluminescent device according to the present invention will be described with reference to the accompanying drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below.

1 is a diagram showing the structure of an organic electroluminescent device according to an embodiment of the present invention.

Referring to FIG. 1, the organic electroluminescent device 100 includes an anode 10; A hole transport region 30; A light emitting layer 40; An electron transport region 50 and a cathode 20 are sequentially stacked, and the hole transport region 30 includes a hole injection layer 31, a hole transport layer 32, and a hole transport auxiliary layer 33. Including, disposed between the hole transport auxiliary layer 33 and the light emitting layer 40, the material of the hole transport auxiliary layer 33 and the light emitting layer 40 are mixed at a predetermined ratio, at least one organic function It has a structure including a layer 60.

Here, the electron transport region 50 may include at least one of the electron transport layer 51 and the electron injection layer 52.

anode

In the organic electroluminescent device 100 according to the present invention, the anode 10 serves to inject holes into the organic material layer (A).

The material constituting the anode 10 is not particularly limited, and a conventional material known in the art may be used. Non-limiting examples thereof include metals such as vanadium, chromium, copper, zinc, and gold; 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 and SnO ₂ :Sb; Conductive polymers such as polythiophene, poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDT), polypyrrole, and polyaniline; And carbon black.

The method of manufacturing the positive electrode 10 is also not particularly limited, and may be manufactured according to a conventional method known in the art. For example, a method of coating an anode material on a substrate made of a silicon wafer, quartz, glass plate, metal plate, or plastic film may be mentioned.

cathode

In the organic electroluminescent device 100 according to the present invention, the cathode 20 serves to inject electrons into the organic material layer (A).

The material forming the negative electrode 20 is not particularly limited, and a conventional material known in the art may be used. Non-limiting examples thereof include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead; Alloys thereof; And multi-layered materials such as LiF/Al and LiO ₂ /Al.

In addition, a method of manufacturing the negative electrode 20 is also not particularly limited, and may be manufactured according to a method known in the art.

Organic layer

The organic material layer (A) included in the organic electroluminescent device according to the present invention can be used without limitation in a conventional configuration used as an organic material layer of an existing organic EL device. For example, a hole transport region 30, a light emitting layer 40, and an electron It may include at least one selected from the group consisting of the transport region 50. In this case, when considering the characteristics of the organic electroluminescent device, it is preferable to include all of the aforementioned organic material layers.

Hole transport area

The hole transport region 30 included in the organic material layer A of the present invention serves to move holes injected from the anode 10 to the emission layer 40. The hole transport region 30 may include at least one selected from the group consisting of a hole injection layer 31, a hole transport layer 32, and a hole transport auxiliary layer 33. At this time, when considering the characteristics of the organic electroluminescent device, it is preferable to include all of the hole injection layer 31, the hole transport layer 32, and the hole transport auxiliary layer 33 described above.

The material constituting the above-described hole injection layer 31 and the hole transport layer 32 is not particularly limited as long as it is a material having a low hole injection barrier and high hole mobility, and the hole injection layer/transport layer material used in the industry is not limited. Can be used. In this case, the material forming the hole injection layer 31 and the hole transport layer 32 may be the same or different from each other.

As the hole injection material, a hole injection material known in the art may be used without limitation. Non-limiting examples of usable hole injection materials include phthalocyanine compounds such as copper phthalocyanine; DNTPD (N,N'-diphenyl-N,N'-bis-[4-(phenyl-m-tolyl-amino)-phenyl]-biphenyl-4,4'-diamine), m-MTDATA(4,4' ,4"-tris(3-methylphenylphenylamino) triphenylamine), TDATA(4,4'4"-Tris(N,N-diphenylamino)triphenylamine), 2TNATA(4,4',4"-tris(N,-(2 -naphthyl)-N-phenylamino}-triphenylamine), PEDOT/PSS(Poly(3,4-ethylenedioxythiophene)/Poly(4-styrenesulfonate)), PANI/DBSA(Polyaniline/Dodecylbenzenesulfonic acid), PANI/CSA(Polyaniline/Camphor) sulfonicacid), PANI/PSS((Polyaniline)/Poly(4-styrenesulfonate)), etc. These can be used alone or in combination of two or more.

In addition, as the hole transport material, a hole transport material known in the art may be used without limitation. Non-limiting examples of usable hole transport materials include carbazole derivatives such as phenylcarbazole and polyvinylcarbazole, fluorene derivatives, TPD(N,N'-bis(3-methylphenyl)-N, Triphenylamine derivatives such as N'-diphenyl-[1,1-biphenyl]-4,4'-diamine), TCTA(4,4',4"-tris(N-carbazolyl)triphenylamine), NPB(N ,N'-di(1-naphthyl)-N,N'-diphenylbenzidine), TAPC(4,4'-Cyclohexylidene bis[N,N-bis(4-methylphenyl)benzenamine]), etc. These are used alone. Or, two or more types may be mixed.

In addition, the material forming the hole transport auxiliary layer 33 is not particularly limited as long as it is a material having a low hole injection barrier and high hole mobility, and materials known in the art may be used without limitation.

In one embodiment according to the present invention, the hole transport auxiliary layer 33 may include a compound represented by Formula 1 below.

In Formula 1,

Y ₁ and Y ₂ are the same or different from each other, each independently selected from the group consisting of a single bond, NR ₃ , O, S, and CR ₄ R ₅ , provided that both Y ₁ and Y ₂ are single bonds Are excluded,

R ₁ to R ₅ are the same as or different from each other, and each independently hydrogen, deuterium, halogen group, cyano group, nitro group, amino group, C ₁ to C ₄₀ alkyl group, C ₂ to C ₄₀ alkenyl group, C ₂ ~ C ₄₀ alkynyl group, C ₃ ~ C ₄₀ cycloalkyl group, 3 to 40 nuclear atoms heterocycloalkyl group, C ₆ ~ C ₆₀ aryl group, 5 to 60 nuclear atoms heteroaryl group, C ₁ ~ C ₄₀ alkyloxy group, C ₆ ~ C ₆₀ aryloxy group, C ₁ ~ C ₄₀ alkylsilyl group, C ₆ ~ C ₆₀ arylsilyl group, C ₁ ~ C ₄₀ alkyl boron group, C ₆ ~ an aryl boronic of C _60, C ₆ ~ C ₆₀ aryl phosphine group, C ₆ ~ C ₆₀ aryl phosphine oxide group, and a C ₆ ~, or selected from the group consisting of an aryl amine of the C ₆₀ in, or they combine adjacent tile Can form a condensed ring;

m and n are each independently an integer of 0 to 4,

The alkyl group, alkenyl group, alkynyl group, aryl group, heteroaryl group, aryloxy group, alkyloxy group, cycloalkyl group, heterocycloalkyl group, arylamine group, alkylsilyl group, alkyl boron group, aryl of the R ₁ to R ₅ A boron group, a phosphine group, a phosphine oxide group, and an arylamine group are each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C ₁ to C ₄₀ alkyl group, C ₂ to C ₄₀ alkenyl group , C ₂ to C ₄₀ alkynyl group, C ₃ to C ₄₀ cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclear atoms, C ₆ to C ₆₀ aryl group, heteroaryl group having 5 to 60 nuclear atoms, C ₁ ~ C ₄₀ alkyloxy group, C ₆ ~ C ₆₀ aryloxy group, C ₁ ~ C ₄₀ alkylsilyl group, C ₆ ~ C ₆₀ arylsilyl group, C ₁ ~ C ₄₀ alkyl boron group, arylboronic group of _{C 6 ~ C 60, C 6} ~ C 60 of the aryl phosphine group, C ₆ ~ C ₆₀ aryl phosphine oxide group and one substituent at least one selected from the group consisting of an aryl amine of the C ₆ ~ C ₆₀ of They may be substituted, and in this case, when the substituents are plural, they may be the same as or different from each other.

The compound represented by Chemical Formula 1 is a carbazole-based or oxanthrene-based mother nucleus having a large electron donating group (EDG) property; Or dibenzo-based mother nuclei (eg, dibenzofuran, dibenzothiophene) having amphoteric physicochemical properties for holes and electrons, and various types on one or both sides of such a mother nucleus A substituent of is introduced. In particular, when one or more electron donor groups (EDG) known in the art are introduced as the substituent, excellent hole characteristics are exhibited. Accordingly, when the compound of Formula 1 is applied as a material for a hole transport layer or a hole transport auxiliary layer, holes can be well received from the anode and thus holes can be smoothly transferred to the light emitting layer, thereby lowering the driving voltage of the device and high efficiency. And it can induce long life.

In addition, the compound represented by Formula 1 not only has a high triplet energy, but also significantly increases the molecular weight of the compound through the control of various types of substituents introduced into the parent nucleus and the position of introduction, resulting in improved glass transition ionicity and high thermal stability. Can have. In addition, since it is effective in suppressing crystallization of the organic material layer, durability and lifespan characteristics of the organic electroluminescent device including the compound according to the present invention can be greatly improved.

According to an embodiment of the present invention, the compound represented by Chemical Formula 1 may be further specified as any one selected from the group of compounds represented by the following Chemical Formula. However, it is not particularly limited thereto.

In the above formula,

R ₁ to R ₅ , m and n are each as defined in Formula 1.

For a preferred embodiment according to the present invention, R ₁ to R ₂ are the same as or different from each other, and each independently hydrogen, deuterium, halogen, cyano group, C ₁ to C ₄₀ alkyl group, C ₆ to C ₆₀ It is selected from the group consisting of an aryl group, a heteroaryl group having 5 to 60 nuclear atoms, and an arylamine group of C ₆ to C ₆₀ , or they are combined with an adjacent group (other R ₁ or R ₂ ) to form a condensed ring Preferred,

R ₃ to R ₅ are the same as or different from each other, and each may be independently selected from a C ₁ to C ₄₀ alkyl group, a C ₆ to C ₆₀ aryl group, and a heteroaryl group having 5 to 60 nuclear atoms,

m and n are each independently an integer of 0 to 4,

In the above R ₁ to R ₅ , the alkyl group, aryl group, heteroaryl group, and arylamine group are each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C ₁ to C ₄₀ alkyl group, C ₂ to C ₄₀ Alkenyl group, C ₂ to C ₄₀ alkynyl group, C ₃ to C ₄₀ cycloalkyl group, heterocycloalkyl group with 3 to 40 nuclear atoms, C ₆ to C ₆₀ aryl group, hetero with 5 to 60 nuclear atoms Aryl group, C ₁ ~ C ₄₀ alkyloxy group, C ₆ ~ C ₆₀ aryloxy group, C ₁ ~ C ₄₀ alkylsilyl group, C ₆ ~ C ₆₀ arylsilyl group, C ₁ ~ C ₄₀ alkyl boron group, one member selected from the group consisting of C ₆ ~ C group ₆₀ arylboronic of, C ₆ ~ C ₆₀ aryl phosphine group, C ₆ ~ C ₆₀ aryl phosphine oxide group, and a C ₆ ~ with an aryl amine of the C ₆₀ of the It may be substituted with more than one substituent, and in this case, when the above substituents are plural, they may be the same as or different from each other.

According to an embodiment of the present invention, the compound represented by Formula 1 is an electron donor (EDG) moiety having a conventional electron donor known in the art on one or both sides of the parent core structure as the center. It may include at least one or more. Specifically, the electron donor (EDG) moiety may be embodied as any one selected from the group of substituents represented by the following structural formula, but is not particularly limited thereto.

In the above formula,

* Means the part where the bond with Formula 1 is formed,

X is O or S,

Ar ₁ and Ar ₂ are the same as or different from each other, and each independently selected from the group consisting of hydrogen, a C ₁ to C ₄₀ alkyl group, a C ₆ to C ₆₀ aryl group, and a heteroaryl group having 5 to 60 nuclear atoms And

The alkyl group, aryl group and heteroaryl group of Ar ₁ and Ar ₂ are each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C ₁ to C ₄₀ alkyl group, C ₂ to C ₄₀ alkenyl group, C ₂ to C ₄₀ alkynyl group, C ₃ to C ₄₀ cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclear atoms, C ₆ to C ₆₀ aryl group, heteroaryl group having 5 to 60 nuclear atoms, C ₁ to C ₄₀ alkyloxy group, C ₆ to C ₆₀ aryloxy group, C ₁ to C ₄₀ alkylsilyl group, C ₆ to C ₆₀ arylsilyl group, C ₁ to C ₄₀ alkyl boron group, C group _{of 6} to arylboronic of C _60, C ₆ to C ₆₀ aryl phosphine group, substituted with one substituent at least one selected from the group consisting of an aryl amine of the C ₆ to C ₆₀ aryl phosphine oxide group, and a C ₆ to C ₆₀ of In this case, when the substituents are plural, they may be the same or different from each other.

Although not specifically indicated in the above structural formula, at least one or more substituents known in the art (eg, the same as the definition of R ₁ to R ₂ ) may be substituted.

The hole transport region 30 may be manufactured through a conventional method known in the art. For example, there are vacuum evaporation method, spin coating method, cast method, LB method (Langmuir-Blodgett), inkjet printing method, laser printing method, laser thermal imaging method (Laser Induced Thermal Imaging, LITI), and the like, but is not limited thereto.

Organic functional layer

The organic functional layer 60 included in the organic material layer (A) according to the present invention is an organic layer that is additionally inserted between the hole transport auxiliary layer 33 and the light emitting layer 40.

The organic functional layer 60 is an organic layer in which two adjacent organic material layers, that is, the material of the hole transport auxiliary layer 33 and the material of the light emitting layer 40, are mixed with each other to be co-depositioned. Since the organic functional layer 60 uses the same material as the material of the organic layer adjacent to each other, it exhibits a barrier-free effect of lowering the barrier between adjacent organic material layers, and thus holes injected from the hole transport auxiliary layer 33 are used. A (hole) may be smoothly supplied from the organic layer to the emission layer 40. Accordingly, since the possibility of forming excitons by meeting holes and electrons in the emission layer 40 increases, the luminous efficiency of the organic electroluminescent device can be improved and lifespan characteristics can be significantly improved.

In order for the organic functional layer 60 according to the present invention to smoothly exhibit the barrier-free effect described above, adjacent organic material layers, such as the hole transport layer 32, the hole transport auxiliary layer 33, and the light emitting layer 40 There is a need to adjust the physical properties between materials as follows.

In one embodiment of the present invention, the HOMO energy level of the hole transport auxiliary layer 33 is to be present between two adjacent organic material layers, specifically, the hole transport layer 32 and the emission layer 40. For example, the HOMO energy level of the hole transport auxiliary layer 33 may be higher than the HOMO energy level of the hole transport layer 32 and lower than the HOMO energy level of the light emitting layer 40 (see FIG. 3 below). Here, the light emitting layer may mean a host.

Specifically, the difference between the HOMO energy level of the hole transport auxiliary layer 33 and the HOMO energy level of the hole transport layer 32 may be greater than 0 eV and less than 1.0 eV, preferably greater than 0 eV and less than 0.5 eV. I can. In addition, the difference between the HOMO energy level of the hole transport auxiliary layer 33 and the HOMO energy level of the emission layer 40 is higher than the difference between the HOMO energy level of the hole transport auxiliary layer 33 and the hole transport layer 32 described above. , 1.0 eV or less, preferably more than 0 eV, may be 0.5 eV or less. When the above-described HOMO energy level difference is satisfied, the HOMO energy levels of the hole transport layer 32, the hole transport auxiliary layer 33, and the light emitting layer 40 are arranged in a stepwise manner (see FIG. 3 below). Accordingly, holes transferred through the anode 10 may be more smoothly transferred to the light emitting layer 40 through a stepwise arrangement of each layer.

In another embodiment of the present invention, the LUMO energy level of the hole transport auxiliary layer 33 may be smaller than the LUMO energy level of the light emitting layer 40 (see FIG. 4 below). Specifically, the difference between the LUMO energy level of the hole transport auxiliary layer 33 and the LUMO energy level of the light emitting layer 40 may be more than 0 eV and less than 1.0 eV, preferably more than 0 eV and less than 0.8 eV. have. That the LUMO energy value of the hole transport auxiliary layer 33 is less than the LUMO energy level value of the light emitting layer 40 means that the LUMO of the energy level hole transport auxiliary layer 33 is formed higher than the light emitting layer 40 (See Figure 4 below). When the above-described LUMO energy level is satisfied, the LUMO energy of the hole transport auxiliary layer 33 forms an energy barrier so that electrons present in the light emitting layer 40 are not transferred to the hole transport auxiliary layer 33, Staying in the emission layer 40 may contribute to the formation of excitons.

For another embodiment of the present invention, the triplet energy T1 of the hole transport auxiliary layer 33 may be greater than the triplet energy T1 of the emission layer 40. As an example, the triplet energy T1 of the hole transport auxiliary layer 33 may be 2.0 eV or more, and specifically 2.3 to 2.9 eV. When the excitons formed in the emission layer 40 move to an adjacent layer according to the triplet energy level, the luminous efficiency of the device decreases. In the present invention, by maintaining the triplet energy value of the hole transport auxiliary layer 33 at least 2.0 eV or more, it is possible to prevent excitons from moving to the hole transport auxiliary layer 33.

In one embodiment of the present invention, the organic functional layer 60 may be manufactured according to a method known in the art using the material of the auxiliary hole transport layer 33 and the material of the light emitting layer 40. For example, it may be formed by co-depositioning a material of the hole transport auxiliary layer 33 and a material of the light emitting layer 40 at a predetermined ratio.

The organic functional layer 60 is not particularly limited as long as it includes the material of the hole transport auxiliary layer 33 and the material of the light-emitting layer 40, as long as the components, structure, thickness, etc. of the organic functional layer 60 are included. For example, the organic functional layer 60 is a single layer formed by co-depositing the material of the hole transport auxiliary layer 33 and the material of the light emitting layer 40, or the material of the hole transport auxiliary layer 33 and the light emitting layer 40 ) A mixture of materials; and at least one heterogeneous material may be a mixture of a mono-layer. Alternatively, it may have a multi-layer structure in which two or more different materials are stacked by forming separate layers, respectively.

Specifically, the organic functional layer 60 includes a compound represented by Formula 1 contained in the hole transport auxiliary layer 33, and a host material and a dopant material contained in the light emitting layer 40. In this case, the mixing ratio of the compound represented by Chemical Formula 1 and the host material is not particularly limited, and may be, for example, 5 to 95: 95 to 5 weight ratio, and specifically 5 to 90: 95 to 10 weight ratio.

In addition, the content of the dopant material may be appropriately adjusted within a conventional range known in the art. For example, the dopant may be included in an amount of 0.5 to 30 parts by weight based on the total weight (eg, 100 parts by weight) of the compound of Formula 1 and the host material, but is not particularly limited thereto.

Emitting layer

The light emitting layer 40 included in the organic material layer (A) of the present invention is a layer in which holes and electrons meet to form excitons, and the color of light emitted by the organic electroluminescent device according to the material forming the light emitting layer 40 is It can be different.

The light emitting layer 40 may include a host and a dopant, and the mixing ratio thereof may be appropriately adjusted within a range known in the art. For example, based on the total weight of the light emitting layer, the host in the range of 70 to 99.9% by weight and the dopant in the range of 0.1 to 30% by weight may be included. More specifically, when the emission layer 40 is blue fluorescence, green fluorescence, or red fluorescence, it may include 80 to 99.9% by weight of a host and 0.1 to 20% by weight of a dopant. In addition, when the emission layer 40 is blue fluorescence, green fluorescence, or red phosphorescence, it may include 70 to 99% by weight of a host and 1 to 30% by weight of a dopant.

The host included in the light emitting layer 40 of the present invention is not particularly limited as long as it is known in the art, and non-limiting examples thereof include an alkali metal complex; Alkaline earth metal complexes; Or condensed aromatic ring derivatives.

More specifically, as host materials, aluminum complexes, beryllium complexes, anthracene derivatives, pyrene derivatives, triphenylene derivatives, carbazole derivatives, dibenzofuran derivatives, and dibenzos that can increase the luminous efficiency and lifetime of organic electroluminescent devices. It is preferred to use a thiophene derivative, or a combination of one or more thereof.

In addition, the dopant included in the light-emitting layer 40 of the present invention is not particularly limited as long as it is known in the art, and non-limiting examples thereof include anthracene derivatives, pyrene derivatives, arylamine derivatives, iridium (Ir) or platinum (Pt ), and the like.

The dopant may be classified into a red dopant, a green dopant, and a blue dopant, and red dopants, green dopants and blue dopants commonly known in the art may be used without particular limitation.

Specifically, non-limiting examples of a red dopant include PtOEP (Pt(II) octaethylporphine: Pt(II) octaethylporphine), Ir(piq)3 (tris(2-phenylisoquinoline)iridium: tris(2-phenylisoquinoline) ) Iridium), Btp2Ir(acac) (bis(2-(2'-benzothienyl)-pyridinato-N,C3')iridium(acetylacetonate): bis(2-(2'-benzothienyl)-pyridinato-N , C3') iridium (acetylacetonate)), or a mixture of two or more thereof.

Further, non-limiting examples of the green dopant include Ir(ppy)3 (tris(2-phenylpyridine) iridium: tris(2-phenylpyridine) iridium), Ir(ppy)2(acac) (Bis(2-phenylpyridine)( Acetylacetonato)iridium(III): bis(2-phenylpyridine)(acetylaceto) iridium(III)), Ir(mppy)3 (tris(2-(4-tolyl)phenylpiridine)iridium: tris(2-(4- Tolyl)phenylpyridine) iridium), C545T (10-(2-benzothiazolyl)-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-[1]benzopyrano [6 ,7,8-ij]-quinolizin-11-one: 10-(2-benzothiazolyl)-1,1,7,7-tetramethyl-2,3,6,7,-tetrahydro-1H,5H ,11H-[1]benzopyrano [6,7,8-ij]-quinolizin-11-one), or mixtures of two or more thereof.

In addition, non-limiting examples of the blue dopant include F2Irpic (Bis[3,5-difluoro-2-(2-pyridyl)phenyl](picolinato)iridium(III): bis[3,5-difluoro-2-( 2-pyridyl)phenyl(picolinato) iridium(III)), (F2ppy)2Ir(tmd), Ir(dfppz)3, DPVBi (4,4'-bis(2,2'-diphenylethen-1-yl) )biphenyl: 4,4'-bis(2,2'-diphenylethen-1-yl)biphenyl), DPAVBi (4,4'-Bis[4-(diphenylamino)styryl]biphenyl: 4,4' -Bis(4-diphenylaminostyryl)biphenyl), TBPe (2,5,8,11-tetra-tert-butyl perylene: 2,5,8,11-tetra-tert-butyl perylene), or And mixtures of two or more of these.

The light emitting layer 40 according to the present invention includes a red light emitting layer comprising a red phosphorescent material; A green light-emitting layer comprising a green phosphorescent material; Alternatively, it may be a blue light-emitting layer including a blue phosphorescent material or a blue phosphorescent material. Preferably, it may be a light emitting layer including a green phosphorescent material.

The above-described light emitting layer 40 may be a single layer or may be formed of a plurality of layers of two or more layers. Here, when the emission layer 40 is a plurality of layers, the organic electroluminescent device may emit light of various colors. Specifically, the present invention can provide an organic electroluminescent device having a mixed color by providing a plurality of light emitting layers made of different materials in series. In addition, when a plurality of emission layers are included, the driving voltage of the device increases, while the current value in the organic electroluminescent device is constant, thereby providing an organic electroluminescent device having improved luminous efficiency by the number of emission layers.

Electron transport area

In the organic electroluminescent device 100 according to the present invention, the electron transport region 50 included in the organic material layer A serves to transfer electrons injected from the cathode 20 to the emission layer 40.

The electron transport region 50 may include at least one selected from the group consisting of the electron transport layer 51 and the electron injection layer 52. At this time, when considering the characteristics of the organic electroluminescent device, it is preferable to include both the electron transport layer 51 and the electron injection layer 52 described above.

In the electron transport region 50 according to the present invention, the electron injection layer 52 may use an electron injection material having easy electron injection and high electron mobility without limitation. Non-limiting examples of the electron injection material that can be used include the above bipolar compounds, anthracene derivatives, heteroaromatic compounds, and alkali metal complex compounds. Specifically, LiF, Li2O, BaO, NaCl, CsF; Lanthanum group metals such as Yb and the like; Alternatively, there are metal halides such as RbCl and RbI, and these may be used alone or in combination of two or more.

The electron transport region 50 according to the present invention, specifically, the electron transport layer 51 and/or the electron injection layer 52 may be co-deposited with an n-type dopant to facilitate injection of electrons from the cathode. At this time, as the n-type dopant, an alkali metal complex compound known in the art may be used without limitation, and examples thereof include an alkali metal, an alkaline earth metal, or a rare earth metal.

The electron transport region 50 may be manufactured through a conventional method known in the art. For example, there are vacuum evaporation method, spin coating method, cast method, LB method (Langmuir-Blodgett), inkjet printing method, laser printing method, laser thermal imaging method (Laser Induced Thermal Imaging, LITI), and the like, but is not limited thereto.

As known in the art, the organic functional layer 53 according to the present invention is a vacuum deposition method, a spin coating method, a cast method, a LB method (Langmuir-Blodgett), an inkjet printing method, a laser printing method, a laser thermal transfer method (Laser It may be formed by Induced Thermal Imaging, LITI), etc., but is not particularly limited thereto.

Light-emitting auxiliary layer

Optionally, the organic light-emitting device 100 of the present invention may further include a light-emitting auxiliary layer (not shown) disposed between the hole transport region 30 and the light-emitting layer 40.

The light-emitting auxiliary layer serves to transport the holes moved from the hole transport region 30 to the light-emitting layer 40 and controls the thickness of the organic material layer (A). This light-emitting auxiliary layer has a high LUMO value to prevent electrons from moving to the hole transport layer 32, and has a high triplet energy to prevent excitons of the light-emitting layer 40 from diffusing to the hole transport layer 32.

This light emission auxiliary layer may include a hole transport material, and may be made of the same material as the hole transport region. Further, the auxiliary light emitting layers of the red, green, and blue organic light emitting devices may be made of the same material.

The material for the auxiliary layer is not particularly limited, and examples thereof include carbazole derivatives or arylamine derivatives. Non-limiting examples of the light emission auxiliary layer that can be used include NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine), TPD (N, N'-bis-(3-methylphenyl)-N, N'-bis ( phenyl)-benzidine), s-TAD, MTDATA(4, 4', 4″-Tris(N-3-methylphenyl-Nphenyl-amino)-triphenylamine). These may be used alone or in combination of two or more. In addition, the light emitting auxiliary layer may include a p-type dopant in addition to the above-described materials. As the p-type dopant, a known p-type dopant used in the art may be used.

Capping layer

Optionally, the organic electroluminescent device 100 of the present invention may further include a capping layer (not shown) disposed on the above-described cathode 20. The capping layer serves to protect the organic light emitting device and help light generated from the organic material layer to be efficiently emitted to the outside.

The capping layer is tris-8-hydroxyquinoline aluminum (Alq3), ZnSe, 2,5-bis(6′-(2′,2″-bipyridyl))-1,1-dimethyl-3,4-diphenylsilole, 4′-bis[N-(1-napthyl)-N-phenyl-amion] biphenyl (α-NPD), N,N′-diphenyl-N,N′-bis(3-methylphenyl)-1,1′- It may contain at least one selected from the group consisting of biphenyl-4,4'-diamine (TPD), 1,1'-bis(di-4-tolylaminophenyl) cyclohexane (TAPC). The material forming the capping layer is inexpensive compared to materials of other layers of the organic light emitting device.

Such a capping layer may be a single layer, but may include two or more layers having different refractive indices, so that the refractive index gradually changes while passing through the two or more layers.

The capping layer may be manufactured by a conventional method known in the art, and for example, various methods such as a vacuum deposition method, a spin coating method, a cast method, or a Langmuir-Blodgett (LB) method may be used.

The organic light emitting device of the present invention including the above-described configuration can be manufactured according to a conventional method known in the art. For example, after vacuum depositing an anode material on a substrate, an organic light-emitting device may be manufactured by vacuum-depositing a material of a hole transport area material, a light emitting layer material, an electron transport area material, and a cathode material on the anode in order. .

2 is a diagram illustrating a structure of an organic electroluminescent device according to another embodiment of the present invention.

Referring to FIG. 2, the organic electroluminescent device 200 includes an anode 10; A hole transport region 30; A light emitting layer 40; An electron transport region 50 and a cathode 20 are sequentially stacked, and the hole transport region 30 includes a hole injection layer 31, a hole transport layer 32, and a hole transport auxiliary layer 33. Including, disposed between the hole transport auxiliary layer 33 and the light emitting layer 40, the material of the hole transport auxiliary layer 33 and the light emitting layer 40 are mixed at a predetermined ratio, at least one organic function It has a structure including a layer 60.

Here, the electron transport region 50 may include at least one or more of the electron transport auxiliary layer 53, the electron transport layer 51, and the electron injection layer 52, and preferably, the electron transport auxiliary layer 53, It includes both the electron transport layer 51 and the electron injection layer 52.

The electron transport auxiliary layer 53 may prevent excitons or holes generated in the emission layer 40 from diffusing into the electron transport region.

The electron transport auxiliary layer 53 may be made of a material having conventional electron transport characteristics known in the art without limitation. For example, oxadiazole derivatives, triazole derivatives, phenanthroline derivatives (eg, BCP), heterocyclic derivatives containing nitrogen, and the like may be included.

The electron transport auxiliary layer 53 is a vacuum evaporation method, a spin coating method, a cast method, an LB method (Langmuir-Blodgett), an inkjet printing method, a laser printing method, a laser induced thermal method, as known in the art. Imaging, LITI) or the like, but is not limited thereto.

Meanwhile, each of the components 10, 20, 30-33, 40, and 51-52 of the organic electroluminescent device illustrated in FIG. 2 is the same as the configuration of FIG. 1, and thus individual descriptions thereof will be omitted.

The organic electroluminescent devices 100 and 200 according to the present invention have a structure in which an anode 10, an organic material layer (A, A'), and a cathode 20 are sequentially stacked, but the anode 10 and the organic material layer (A, A') or between the cathode 20 and the organic material layers (A, A') may further include an insulating layer or an adhesive layer. The organic electroluminescent device according to the present invention may have excellent lifespan characteristics because, when voltage, current, or both are applied, the life time of initial brightness is increased while maintaining maximum luminous efficiency.

Hereinafter, the present invention will be described in detail through examples, but the following examples are only illustrative of the present invention, and the present invention is not limited by the following examples.

[Preparation Example] Compounds 1 to 20

The compounds of the present invention were prepared as follows, and their HOMO, LUMO, and triplet energies were measured by methods known in the art, respectively, and are shown in Table 1 below. In addition, ADN compound and NPB compound were used as controls.

1) Triplet energy was measured with a phosphorescence spectrum at 77K, and measured with a QuantaMaster 30 Spectrofluorometer (PTI). A sample was prepared by dissolving a sample at a concentration of 10 ^-4 M in 2-methylTHF solvent, and then, a phosphorescence spectrum was measured at a low temperature of 77 K using liquid nitrogen.

2) HOMO energy level was measured by CV (cyclic voltammetry) method.

3) LUMO energy was obtained by calculating the bandgap energy by UV spectrum, and then by the difference of the HOMO value from the bandgap energy.

compound HOMO (eV) LUMO (eV) Triplet energy (eV) One 5.44 2.28 2.6 2 5.47 2.26 2.7 3 5.29 2.22 2.6 4 5.39 2.26 2.8 5 5.32 2.03 2.5 6 5.65 2.17 2.7 7 5.69 2.18 2.6 8 5.58 2.14 2.7 9 5.75 2.25 2.5 10 5.59 2.24 2.7 11 5.58 2.15 2.7 12 5.73 2.27 2.6 13 5.61 2.18 2.6 14 5.66 2.22 2.7 15 5.56 2.17 2.6 16 5.52 2.26 2.5 17 5.38 2.25 2.4 18 5.49 2.21 2.2 19 5.51 2.19 2.3 20 5.43 2.24 2.4 ADN 5.80 2.62 1.73 NPB 5.03 1.45 2.5

[Examples 1 to 20] Fabrication of blue organic electroluminescent devices

After the compound prepared in Preparation Example was subjected to high-purity sublimation purification by a commonly known method, a blue organic electroluminescent device was manufactured according to the following procedure.

First, the glass substrate coated with ITO (Indium tin oxide) to a thickness of 1500 Å was washed with distilled water and ultrasonic waves. After washing with distilled water, ultrasonically clean with a solvent such as isopropyl alcohol, acetone, methanol, etc., dry, transfer to a UV OZONE cleaner (Power Sonic 405, Hwashin Tech), and clean the substrate for 5 minutes using UV And transferred the substrate to a vacuum evaporator.

On the ITO transparent electrode prepared as above, DS-205 (Doosan Electronics 80 nm)/NPB (15 nm)/compound (A) (5 nm) in Table 1/ADN + 5% DS-405 + compound in Table 1 (A') (5nm)/ ADN + 5% DS-405 (Doosan Electronics, 25nm)/Alq ₃ (30 nm)/LiF (1 nm)/Al (200 nm) in order to form an organic EL device. Was prepared (see Table 2 below).

compound Thickness (nm) Hole injection layer DS-205 80 Hole transport layer NPB 15 Hole transport auxiliary layer Each compound 1-20 in Table 1 5 Organic functional layer ADN + 5% DS-405+ Each compound 1-20 of Table 1 5 Emitting layer ADN + 5% DS-405 25 Electron transport layer Alq ₃ 25 Electron injection layer LiF One cathode Al 200

[Comparative Example 1] Preparation of blue organic electroluminescent device

A blue organic electroluminescent device of Comparative Example 1 was manufactured in the same manner as in Example 1, except that the organic functional layer was not used and the emission layer was deposited at 30 nm.

[Comparative Example 2] Preparation of blue organic electroluminescent device

The blue organic electric field of Comparative Example 2 was carried out in the same manner as in Example 1, except that a hole transport auxiliary layer (eg, compound 2) and a compound different from the light emitting layer material (eg, compound 14) were used as organic functional layer components. A light-emitting device was fabricated.

For reference, the structures of NPB, ADN, and Alq ₃ used in Examples 1 to 20 and Comparative Example 1 are as follows, respectively.

[Evaluation Example 1]

For the organic electroluminescent devices prepared in Examples 1 to 20 and Comparative Examples 1 to 2, respectively, the driving voltage, emission wavelength, and current efficiency at a current density of 10 mA/cm 2 were measured, and the results are shown in Table 3 below. Indicated.

Sample Hole transport
Auxiliary layer material
(a) Organic functional layer Driving voltage
(V) Emission peak
(nm) Current efficiency
(cd/A) a' Weight ratio
(a': ADN: DS-405) Example 1 One One 50: 50: 5 4.2 456 7.7 Example 2 2 2 50: 50: 5 4.1 452 7.6 Example 3 3 3 50: 50: 5 4.1 450 7.4 Example 4 4 4 50: 50: 5 3.8 452 7.4 Example 5 5 5 50: 50: 5 3.7 455 7.5 Example 6 6 6 50: 50: 5 4.0 452 7.8 Example 7 7 7 50: 50: 5 4.0 455 7.2 Example 8 8 8 50: 50: 5 3.9 455 7.9 Example 9 9 9 50: 50: 5 4.1 452 7.9 Example 10 10 10 50: 50: 5 4.1 455 7.8 Example 11 11 11 50: 50: 5 3.7 455 7.6 Example 12 12 12 50: 50: 5 3.7 458 7.4 Example 13 13 13 50: 50: 5 3.8 455 7.7 Example 14 14 14 50: 50: 5 4.2 456 7.7 Example 15 15 15 50: 50: 5 4.2 455 7.5 Example 16 16 16 5: 95: 5 4.3 458 7.5 Example 17 17 17 20: 80: 5 4.1 455 7.6 Example 18 18 18 40: 60: 5 4.2 456 7.4 Example 19 19 19 70: 30: 5 4.0 455 7.2 Example 20 20 20 90: 10: 5 4.1 458 7.6 Comparative Example 1 - - - 4.8 458 6.2 Comparative Example 2 2 14 50: 50: 5 4.5 457 6.8

As shown in Table 3, the blue organic electroluminescent devices of Examples 1 to 20 including an organic functional layer in which materials for a hole transport auxiliary layer and a light emitting layer are mixed according to the present invention are non-organic functional layers. Blue organic electroluminescent device of Comparative Example 1 including; And it was found that the hole transport auxiliary layer and the organic functional layer exhibited superior performance in terms of current efficiency, emission peak, and driving voltage compared to the organic electroluminescent device of Comparative Example 2 in which different materials were used.

Claims (13)

anode; Hole transport area; Light-emitting layer; It has a structure in which an electron transport region and a cathode are sequentially stacked,
The hole transport region includes a hole injection layer, a hole transport layer, and a hole transport auxiliary layer,
Further comprising at least one organic functional layer disposed between the hole transport auxiliary layer and the emission layer,
The organic functional layer may include a material for the emission layer; And a mixture of materials for the hole transport auxiliary layer. The method of claim 1,
The HOMO energy level of the hole transport auxiliary layer is higher than the HOMO energy level of the hole transport layer and lower than the HOMO energy level of the emission layer. The method of claim 2,
The difference between the HOMO energy level of the hole transport auxiliary layer and the HOMO energy level of the hole transport layer is greater than 0 eV and less than or equal to 1.0 eV, an organic electroluminescent device. The method of claim 3,
The difference between the HOMO energy level of the hole transport auxiliary layer and the HOMO energy level of the light emitting layer is higher than the difference between the HOMO energy level of the hole transport auxiliary layer and the hole transport layer, and is 1.0 eV or less. The method of claim 1,
The LUMO energy level of the hole transport auxiliary layer is less than the LUMO energy level of the emission layer. The method of claim 5,
The difference between the LUMO energy level of the hole transport auxiliary layer and the LUMO energy level of the emission layer is greater than 0 eV and less than or equal to 1.0 eV, an organic electroluminescent device. The method of claim 1,
The triplet energy (T1) of the hole transport auxiliary layer is 2.0 eV or more, an organic electroluminescent device. The method of claim 1,
The hole transport auxiliary layer is an organic electroluminescent device comprising a compound represented by the following Formula 1:
[Formula 1]

In Formula 1,
Y ₁ and Y ₂ are the same or different from each other, each independently selected from the group consisting of a single bond, NR ₃ , O, S, and CR ₄ R ₅ , provided that both Y ₁ and Y ₂ are single bonds Are excluded,
R ₁ to R ₅ are the same as or different from each other, and each independently hydrogen, deuterium, halogen group, cyano group, nitro group, amino group, C ₁ to C ₄₀ alkyl group, C ₂ to C ₄₀ alkenyl group, C ₂ ~ C ₄₀ alkynyl group, C ₃ ~ C ₄₀ cycloalkyl group, 3 to 40 nuclear atoms heterocycloalkyl group, C ₆ ~ C ₆₀ aryl group, 5 to 60 nuclear atoms heteroaryl group, C ₁ ~ C ₄₀ alkyloxy group, C ₆ ~ C ₆₀ aryloxy group, C ₁ ~ C ₄₀ alkylsilyl group, C ₆ ~ C ₆₀ arylsilyl group, C ₁ ~ C ₄₀ alkyl boron group, C ₆ ~ an aryl boronic of C _60, C ₆ ~ C ₆₀ aryl phosphine group, C ₆ ~ C ₆₀ aryl phosphine oxide group, and a C ₆ ~, or selected from the group consisting of an aryl amine of the C ₆₀ in, or they combine adjacent tile Can form a condensed ring;
m and n are each independently an integer of 0 to 4,
The alkyl group, alkenyl group, alkynyl group, aryl group, heteroaryl group, aryloxy group, alkyloxy group, cycloalkyl group, heterocycloalkyl group, arylamine group, alkylsilyl group, alkyl boron group, aryl of the R ₁ to R ₅ A boron group, a phosphine group, a phosphine oxide group, and an arylamine group are each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C ₁ to C ₄₀ alkyl group, C ₂ to C ₄₀ alkenyl group , C ₂ to C ₄₀ alkynyl group, C ₃ to C ₄₀ cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclear atoms, C ₆ to C ₆₀ aryl group, heteroaryl group having 5 to 60 nuclear atoms, C ₁ ~ C ₄₀ alkyloxy group, C ₆ ~ C ₆₀ aryloxy group, C ₁ ~ C ₄₀ alkylsilyl group, C ₆ ~ C ₆₀ arylsilyl group, C ₁ ~ C ₄₀ alkyl boron group, arylboronic group of _{C 6 ~ C 60, C 6} ~ C 60 of the aryl phosphine group, C ₆ ~ C ₆₀ aryl phosphine oxide group and one substituent at least one selected from the group consisting of an aryl amine of the C ₆ ~ C ₆₀ of They may be substituted, and in this case, when the substituents are plural, they may be the same as or different from each other. The method of claim 8,
The compound represented by Formula 1 is an organic electroluminescent device selected from the group of compounds represented by the following formula:

In the above formula,
R ₁ to R ₅ , m and n are each as defined in claim 8. The method of claim 8,
The compound represented by Formula 1 is an organic electroluminescent device comprising at least one moiety selected from the group of substituents represented by the following structural formula:

In the above formula,
* Means the part where the bond with Formula 1 is formed,
X is O or S,
Ar ₁ and Ar ₂ are the same as or different from each other, and each independently selected from the group consisting of hydrogen, a C ₁ to C ₄₀ alkyl group, a C ₆ to C ₆₀ aryl group, and a heteroaryl group having 5 to 60 nuclear atoms And
The alkyl group, aryl group and heteroaryl group of Ar ₁ and Ar ₂ are each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C ₁ to C ₄₀ alkyl group, C ₂ to C ₄₀ alkenyl group, C ₂ to C ₄₀ alkynyl group, C ₃ to C ₄₀ cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclear atoms, C ₆ to C ₆₀ aryl group, heteroaryl group having 5 to 60 nuclear atoms, C ₁ to C ₄₀ alkyloxy group, C ₆ to C ₆₀ aryloxy group, C ₁ to C ₄₀ alkylsilyl group, C ₆ to C ₆₀ arylsilyl group, C ₁ to C ₄₀ alkyl boron group, C group _{of 6} to arylboronic of C _60, C ₆ to C ₆₀ aryl phosphine group, substituted with one substituent at least one selected from the group consisting of an aryl amine of the C ₆ to C ₆₀ aryl phosphine oxide group, and a C ₆ to C ₆₀ of In this case, when the substituents are plural, they may be the same or different from each other. The method of claim 1,
The organic functional layer is a material of the auxiliary hole transport layer; And an organic electroluminescent device formed by co-depositing a material for the emission layer. The method of claim 8,
The organic functional layer includes a compound of Formula 1 contained in the hole transport auxiliary layer, a host material and a dopant material contained in the emission layer,
The mixing ratio of the compound of Formula 1 and the host material is 5 to 95: 95 to 5 weight ratio,
The dopant material is included in an amount of 0.5 to 30 parts by weight based on the total weight of the compound of Formula 1 and the host material. The method of claim 1,
The electron transport region is an organic electroluminescent device including at least one of an electron transport auxiliary layer, an electron transport layer, and an electron injection layer.

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