KR102297602B1 - Organic light emitting diode device - Google Patents

Abstract

An organic electroluminescent device according to an embodiment of the present invention includes at least two light emitting units including a light emitting layer and an electron transport layer, and a charge generating layer positioned between the light emitting units, the charge generating layer and the electron transport layer At least one of them is characterized in that it is composed of a compound containing a nitrogen atom and a substituent that increases electron mobility.

Description

Organic electroluminescent device {ORGANIC LIGHT EMITTING DIODE DEVICE}

The present invention relates to an organic light emitting device, and more particularly, to an organic light emitting device capable of improving driving voltage, current efficiency, and lifespan characteristics of the organic light emitting device.

A video display device that implements various information on a screen is a key technology in the information and communication era, which is developing in the direction of thinner, lighter, more portable and high-performance. With the recent development of the information society, as the demand for various types of display devices increases, LCD (Liquid Crystal Display), PDP (Plasma Display Panel), ELD (Electro Luminescent Display), FED (Field Emission Display), OLED ( Organic Light Emitting Diode) and other flat panel display devices are being actively researched.

Among them, the organic light emitting device is a device that emits light while electrons and holes are paired and then disappear when electric charges are injected into the organic light emitting layer formed between the anode and the cathode. The organic electroluminescent device can be formed on a flexible transparent substrate such as plastic, and can be driven at a lower voltage than a plasma display panel or an inorganic electroluminescent (EL) display, and power consumption is relatively low. It has the advantage of being small and the color is excellent. In particular, the organic electroluminescent device for realizing white color is a device that is used for various purposes, such as a thin light source, a backlight of a liquid crystal display device, or a full-color display device employing a color filter as well as lighting.

In the development of white organic light emitting diodes, research and development are in progress according to each method because high efficiency and long lifespan, as well as color purity, color stability according to changes in current and voltage, and ease of device manufacturing are important. There are various structures of the white organic light emitting device, and it can be broadly divided into a single layer light emitting structure, a multilayer light emitting structure, and the like. Among them, a multilayer light emitting structure in which a fluorescent blue light emitting layer and a phosphorescent yellow light emitting layer are stacked (tandem) is mainly adopted for a long-life white device.

Specifically, a phosphorescent light emitting unit stacked structure in which a first light emitting unit using a blue fluorescent device as a light emitting layer and a second light emitting unit using a yellow-green phosphorescent device as a light emitting layer are stacked is used. have. In such a white organic light emitting device, white light is realized by a mixing effect of blue light emitted from a blue fluorescent device and yellow light emitted from a yellow green phosphorescent device. Here, a charge generation layer is provided between the first light emitting unit and the second light emitting unit to double the efficiency of current generated in the light emitting layer and to facilitate charge distribution. The charge generation layer is a layer that generates electric charges, that is, electrons and holes inside, doubles the efficiency of current generated in the light emitting layer, and facilitates charge distribution, thereby preventing the driving voltage from being increased.

However, in the conventional charge generation layer, the N-type charge generation layer and the P-type charge generation layer have a PN junction structure. Due to the charge generation at the hole injection layer interface, the electron injection property into the N-type charge generation layer is deteriorated. In addition, when the N-type charge generation layer is doped with an alkali metal, the alkali metal diffuses into the P-type charge generation layer, thereby reducing the lifetime of the device.

The present invention provides an organic light emitting device capable of improving driving voltage, efficiency, and lifespan characteristics of the organic light emitting device.

In order to achieve the above object, an organic light emitting diode according to an embodiment of the present invention includes a first electrode and a second electrode opposite to each other on a substrate, and is positioned between the first and second electrodes and emits a specific light In the organic electroluminescent device comprising at least two or more light emitting units including a light emitting layer to such a transport layer, wherein at least one of the charge generation layer and the electron transport layer is composed of a compound containing a nitrogen atom and a substituent for increasing electron mobility.

Since the compound containing a nitrogen atom of the present invention is rich in electrons by including two nitrogen atoms, it has a fast electron mobility to facilitate electron transport. Therefore, in the organic light emitting device of the present invention, by using a compound in at least one of the electron transport layers included in the light emitting part, electrons transferred from the N-type charge generation layer can be efficiently transferred to the light emitting layer, so that the efficiency can be improved.

In addition, the compound containing a nitrogen atom of the present invention contains ^{nitrogen (N) of sp 2} hybrid orbital, which is relatively rich in electrons, and this nitrogen is bound to an alkali metal or alkaline earth metal as a dopant in the N-type charge generating layer. ) to form a gap state. By the formed gap state, it is possible to smoothly transfer electrons from the N-type charge generation layer to the electron transport layer. Accordingly, in the organic electroluminescent device of the present invention, by using the compound of the present invention in the N-type charge generating layer, electrons can be smoothly transferred from the N-type charge generating layer to the electron transporting layer. In addition, since the compound containing the nitrogen atom is combined with the alkali metal or alkaline earth metal included in the N-type charge generating layer, the alkali metal or alkaline earth metal does not diffuse into the P-type charge generating layer, and thus the lifespan may be improved.

Accordingly, the organic electroluminescent device of the present invention uses a compound containing a nitrogen atom in at least one of the electron transporting layers and the N-type charge generating layers included in the light emitting part, so that electrons transferred from the N-type charge generating layer are transferred to the light emitting layer. It is possible to improve device efficiency and device performance by efficiently transferring it to In addition, since electrons are smoothly transferred from the N-type charge generating layer to the electron transport layer, the problem of a decrease in lifespan caused by poor electron injection can be improved. Further, it is possible to improve a problem in that a driving voltage generated when electrons injected into the N-type charge generation layer moves to the electron transport layer due to a difference in LUMO energy level between the electron transport layer and the N-type charge generation layer is increased.

1 is a cross-sectional view showing an organic electroluminescent device according to first and second embodiments of the present invention.
2 is a cross-sectional view showing an organic electroluminescent device according to third and fourth embodiments of the present invention.
3 is a graph showing the glass transition temperature of compound NC09.
4 is a graph showing the glass transition temperature of compound NC12.
5 is a graph showing the melting point of compound NC12.
6 is a graph showing the glass transition temperature of compound NC17.
7 is a graph showing the melting point of compound NC17.
8 is a graph showing the glass transition temperature of compound NC34.
9 is a graph showing the glass transition temperature of compound NC42.
10 is a graph showing the melting point of compound NC42.
11 is a graph showing the glass transition temperature of compound NC43.
12 is a graph showing the melting point of compound NC43.
13 is a graph showing the current density according to the driving voltage of the organic light emitting diodes manufactured according to Comparative Examples and Examples 1 to 6 of the present invention.
14 is a graph showing emission spectra of organic light emitting diodes prepared according to Comparative Examples and Examples 1 to 6 of the present invention.
15 is a graph showing the rate of decrease in luminance over time of organic light emitting diodes prepared according to Comparative Examples and Examples 1 to 6 of the present invention;
16 is a graph showing the current density according to the driving voltage of the organic light emitting diodes manufactured according to Comparative Examples and Examples 7 to 10 of the present invention.
17 is a graph showing emission spectra of organic light emitting diodes prepared according to Comparative Examples and Examples 7 to 10 of the present invention.
18 is a graph showing the rate of decrease in luminance according to time of the organic light emitting diodes prepared according to Comparative Examples and Examples 7 to 10 of the present invention.
19 is a graph showing the current density according to the driving voltage of the organic light emitting device manufactured according to Comparative Examples and Examples 11 to 14 of the present invention.
20 is a graph showing emission spectra of organic light emitting diodes prepared according to Comparative Examples and Examples 11 to 14 of the present invention.
21 is a graph showing the rate of decrease in luminance according to time of the organic light emitting diodes prepared according to Comparative Examples and Examples 11 to 14 of the present invention.
22 is a graph showing the current density according to the driving voltage of the organic light emitting diodes manufactured according to Comparative Examples and Examples 15 to 17 of the present invention.
23 is a graph showing emission spectra of organic light emitting diodes prepared according to Comparative Examples and Examples 15 to 17 of the present invention.
24 is a graph showing the rate of decrease in luminance according to time of the organic light emitting diodes prepared according to Comparative Examples and Examples 15 to 17 of the present invention.
25 is a graph showing the current density according to the driving voltage of the organic light emitting diodes manufactured according to Comparative Examples and Examples 18 and 19 of the present invention.
26 is a graph showing emission spectra of organic light emitting diodes prepared according to Comparative Examples and Examples 18 and 19 of the present invention.
27 is a graph showing the rate of decrease in luminance according to time of the organic light emitting diodes manufactured according to Comparative Examples, Examples 18 and 19 of the present invention;
28 is a graph showing the current density according to the driving voltage of the organic light emitting diodes manufactured according to Comparative Examples, Examples 20 and 21 of the present invention;
29 is a graph showing emission spectra of organic light emitting diodes prepared according to Comparative Examples, Examples 20 and 21 of the present invention;
30 is a graph showing the rate of decrease in luminance over time of the organic light emitting diodes manufactured according to Comparative Examples, Examples 20 and 21 of the present invention;

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, proportions, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative and the present invention is not limited to the illustrated matters. Like reference numerals refer to like elements throughout. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. When 'including', 'having', 'consisting', etc. mentioned in this specification are used, other parts may be added unless 'only' is used. When a component is expressed in the singular, the case in which the plural is included is included unless otherwise explicitly stated.

In interpreting the components, it is interpreted as including an error range even if there is no separate explicit description.

In the case of a description of the positional relationship, for example, when the positional relationship of two parts is described as 'on', 'on', 'on', 'beside', etc., 'right' Alternatively, one or more other parts may be positioned between the two parts unless 'directly' is used.

In the case of a description of a temporal relationship, for example, 'immediately' or 'directly' when a temporal relationship is described with 'after', 'following', 'after', 'before', etc. It may include cases that are not continuous unless this is used.

Although the first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from another. Accordingly, the first component mentioned below may be the second component within the spirit of the present invention.

Each feature of the various embodiments of the present invention may be partially or wholly combined or combined with each other, technically various interlocking and driving are possible, and each of the embodiments may be implemented independently of each other or may be implemented together in a related relationship. may be

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view showing an organic electroluminescent device according to first and second embodiments of the present invention.

Referring to FIG. 1 , an organic light emitting diode 100 according to a first embodiment of the present invention includes light emitting units ST1 and ST2 and light emitting units ST1 and ST2 positioned between an anode 110 and a cathode 220 . ) and a charge generation layer 160 positioned between them.

The anode 110 is an electrode for injecting holes and may be any one of indium tin oxide (ITO), indium zinc oxide (IZO), and zinc oxide (ZnO) having a high work function. In addition, when the anode 110 is a reflective electrode, the anode 110 includes a reflective layer made of any one of aluminum (Al), silver (Ag), or nickel (Ni) under a layer made of any one of ITO, IZO, and ZnO. may include more.

The first light emitting part ST1 constitutes one light emitting device unit, and includes the first light emitting layer 140 . The first light emitting layer 140 may emit any one of red, green, and blue, but in the present embodiment may be a blue light emitting layer that emits blue. The blue light emitting layer includes one of a blue light emitting layer, a dark blue light emitting layer, or a sky blue light emitting layer. Alternatively, the first light emitting layer 140 may include a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a green light emitting layer.

The first light emitting part ST1 includes the hole injection layer 120 and the first hole transport layer 130 between the anode 110 and the first light emitting layer 140 , and is located on the first light emitting layer 140 . 1 includes an electron transport layer 150 .

The hole injection layer 120 may serve to smoothly inject holes from the anode 110 to the first light emitting layer 140 , and may include cupper phthalocyanine (CuPc), poly(3,4)-ethylenedioxythiophene (PEDOT) And PANI (polyaniline) may be made of any one or more selected from the group consisting of, but is not limited thereto. The hole injection layer 120 may have a thickness of 1 to 150 nm. Here, when the thickness of the hole injection layer 120 is 1 nm or more, hole injection characteristics can be improved, and when it is 150 nm or less, an increase in the thickness of the hole injection layer 120 can be prevented, thereby preventing an increase in the driving voltage. The hole injection layer 120 may not be included in the configuration of the organic light emitting diode depending on the structure or characteristics of the organic light emitting diode.

The first hole transport layer 130 serves to facilitate hole transport, and NPD (N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)-2,2') -dimethylbenzidine), TPD(N,N'-bis-(3-methylphenyl)-N,N'-bis-(phenyl)-benzidine), spiro-TAD(2,2',7,7'-tetrakis(N ,N-diphenylamino)-9,9'-spirofluorene) and MTDATA (4,4',4"-Tris(N-3-methylphenyl-N-phenylamino)-triphenylamine) may consist of any one or more selected from the group consisting of However, the thickness of the first hole transport layer 130 may be 1 nm to 150 nm. Here, if the thickness of the first hole transport layer 130 is 1 nm or more, hole transport characteristics may be improved, and the thickness of the first hole transport layer 130 may be improved to 150 nm. Below, it is possible to prevent an increase in the thickness of the first hole transport layer 130 to prevent an increase in the driving voltage.

The first emission layer 140 may emit red (R), green (G), blue (B), or yellow (Y) light, and may be formed of a phosphorescent material or a fluorescent material.

When the first light emitting layer 140 is red, it includes a host material such as CBP (4,4'-bis(carbazol-9-yl)biphenyl), and PIQIr(acac)(bis(1-phenylisoquinoline)acetylacetonate iridium) , PQIr (acac) (bis (1-phenylquinoline) acetylacetonate iridium), PQIr (tris (1-phenylquinoline) iridium) and PtOEP (octaethylporphyrin platinum) as a phosphor containing a dopant containing any one or more selected from the group consisting of may be made, but is not limited thereto. Alternatively, PBD:Eu(DBM) ₃ (Phen) or a fluorescent material including Perylene, but is not limited thereto. In addition, when the first light emitting layer 140 is red, the light emitting area may be in a range of 600 nm to 650 nm.

When the first light emitting layer 140 is green, it includes a host material such as CBP (4,4'-bis(carbazol-9-yl)biphenyl), and phosphorescence including a dopant material including an iridium series. It may be made of a material, but is not limited thereto. Alternatively, _{it may be made of a fluorescent material including Alq 3} (tris(8-hydroxyquinolinato)aluminum), but is not limited thereto. In addition, when the first emission layer 140 is green, the emission area may be in a range of 510 nm to 570 nm.

When the first light emitting layer 140 is blue, it includes a host material such as CBP (4,4'-bis(carbazol-9-yl)biphenyl), and phosphorescence including a dopant material including an iridium series. It may be made of a material, but is not limited thereto. Alternatively, spiro-DPVBi, spiro-CBP, distylbenzene (DSB), distrylarylene (DSA), may be made of a fluorescent material including any one selected from the group consisting of PFO-based polymers and PPV-based polymers, but limited thereto doesn't happen In addition, the first light emitting layer 140 may include a sky blue light emitting layer or a deep blue light emitting layer in addition to the blue light emitting layer. Accordingly, the emission area of the first emission layer 140 may be in a range of 440 nm to 480 nm. Alternatively, a blue light emitting layer and a red light emitting layer may be configured as two light emitting layers in the first light emitting part ST1 in order to improve the red efficiency of the organic light emitting diode. When the blue light emitting layer and the red light emitting layer are configured, the light emitting area may be in the range of 440 nm to 650 nm.

When the first light emitting layer 140 is yellow, a single layer structure of a light emitting layer that emits yellow-green or a light emitting layer that emits green light, or a multilayer structure of a yellow green light emitting layer and a light emitting layer that emits green light can be made with Here, the yellow light emitting layer includes a yellow-green light emitting layer or a green light emitting layer or a multilayer structure of a yellow green light emitting layer and a green light emitting layer. In this embodiment, a single-layer structure of a yellow light emitting layer emitting yellow green will be described as an example. The yellow light emitting layer is yellow green on at least one host selected from CBP (4,4'-bis (carbazol-9-yl) biphenyl) or BAlq (Bis (2-methyl-8-quinolinolate) -4- (phenylphenolato) aluminum) It may be made of a phosphorescent yellow-green dopant that emits light. In addition, the emission area of the yellow-green emission layer may be in the range of 510 nm to 590 nm. In order to improve the red efficiency of the organic light emitting diode, a yellow green light emitting layer and a red light emitting layer may be configured as two light emitting layers in the first light emitting part ST1 . When the yellow green light emitting layer and the red light emitting layer are configured, the light emitting area may be in the range of 510 nm to 650 nm.

The first electron transport layer 150 serves to facilitate electron transport, and Alq ₃ (tris(8-hydroxy-quinolinato)aluminum), PBD(2-(4-biphenyl)-5-(4-tert) -butylphenyl)-1,3,4-oxadiazole), TAZ(3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole), and BAlq(Bis(2-methyl -8-quinolinolate)-4-(phenylphenolato)aluminum) may be used, but is not limited thereto. The thickness of the first electron transport layer 150 may be 1 to 150 nm. Here, if the thickness of the first electron transport layer 150 is 1 nm or more, there is an advantage in that it is possible to prevent the electron transport characteristics from being deteriorated, and if it is 150 nm or less, the thickness of the first electron transport layer 150 is prevented from increasing to increase the driving voltage. rise can be prevented.

The first light emitting part ST1 includes the hole injection layer 120 and the first hole transport layer 130 between the anode 110 and the first light emitting layer 140 , and the first electrons on the first light emitting layer 140 . and a transport layer 150 . Accordingly, the first light emitting part ST1 including the hole injection layer 120 , the first hole transport layer 130 , the first light emitting layer 140 , and the first electron transport layer 150 on the anode 110 is configured. . The hole injection layer 120 may not be included in the configuration of the first light emitting part ST1 depending on the structure or characteristics of the device.

A charge generation layer (CGL) 160 is positioned between the first light emitting part ST1 and the second light emitting part ST2 . The first light emitting part ST1 and the second light emitting part ST2 have a structure connected by the charge generation layer 160 . The charge generation layer 160 may be a PN junction charge generation layer in which an N-type charge generation layer 160N and a P-type charge generation layer 160P are joined. In this case, the PN junction charge generation layer 160 generates charges or separates holes and electrons into holes and electrons to inject holes and electrons into the light emitting layer. That is, the N-type charge generation layer 160N transfers electrons to the first electron transport layer 150 , and the first electron transport layer 150 supplies electrons to the first light emitting layer 140 adjacent to the anode. The P-type charge generating layer 160P transfers holes to the second hole transport layer 180 and supplies holes to the second light emitting layer 190 of the second light emitting part ST2, thereby providing an organic layer having a plurality of light emitting layers. The luminous efficiency of the electroluminescent device can be further increased, and the driving voltage can also be lowered. Accordingly, the charge generation layer 160 has an important influence on the luminous efficiency or driving voltage, which are characteristics of the organic light emitting diode.

Accordingly, the present inventors conducted various experiments to improve the electron injection characteristics of the N-type charge generation layer. Through this experiment, it was recognized that the driving voltage increases when electrons injected into the N-type charge generation layer move to the electron transport layer due to the difference in LUMO energy level between the electron transport layer and the N-type charge generation layer. Therefore, the compound of the present invention was introduced into the N-type charge generation layer through various experiments in order to select materials for the electron transport layer and the N-type charge generation layer that can reduce the driving voltage and improve the efficiency. The compound containing a nitrogen atom of the present invention includes two electron-rich nitrogen (N), thereby facilitating electron transport by having fast electron mobility. In addition, the compound of the present invention ^{contains nitrogen (N) of sp 2} hybrid orbital, which is relatively rich in electrons, and this nitrogen binds to an alkali metal or alkaline earth metal, which is a dopant of the N-type charge generating layer, to form a gap state ( gap state). Therefore, by the formed gap state, it is possible to facilitate the transfer of electrons from the N-type charge generation layer to the electron transport layer. In addition, since nitrogen is combined with an alkali metal or alkaline earth metal included in the N-type charge generation layer, the alkali metal or alkaline earth metal does not diffuse into the P-type charge generation layer, and thus lifespan can be improved.

The compound used in the N-type charge generation layer 160N in an embodiment of the present invention is represented by the following Chemical Formula 1.

[Formula 1]

In Formula 1, Ar ₁ is phenanthrolinyl or phenanthrollinylene, Ar ₂ and Ar ₃ are each independently hydrogen, a substituted or unsubstituted aryl group having 6 to 60 carbon atoms, It is selected from a substituted or unsubstituted heteroaryl group having 3 to 60 carbon atoms and an alkyl group having 1 to 20 carbon atoms. L ₁ and L ₃ are each independently selected from a single bond, a substituted or unsubstituted C 6 to C 60 aryl group, a substituted or unsubstituted C 3 to C 60 heteroaryl group and a C 1 to C 20 alkyl group, L ₂ is selected from a single bond, substituted or unsubstituted anthracenylene, and substituted or unsubstituted pyrenylene.

More specifically, Ar ₂ and Ar ₃ are each independently hydrogen, substituted or unsubstituted phenyl (phenyl), alkylphenyl (alkylphenyl), biphenyl (biphenyl), alkylbiphenyl (alkylbiphenyl), halophenyl (halophenyl) , alkoxyphenyl, haloalkoxyphenyl, cyanophenyl, silylphenyl, naphthyl, alkylnaphthyl, halonaphthyl, cyanonaph Tyl (cyanonaphthyl), silylnaphthyl, pyridyl, alkylpyridyl, halopyridyl, cyanopyridyl, alkoxypyridyl, silylpyridyl (silylpyridyl), pyrimidyl (pyrimidyl), halopyrimidyl (halopyrimidyl), cyanopyridimyl, alkoxypyrimidyl (alkoxypyrimidyl), quinolinyl, isoquinolinyl (isoquinolinyl), quinoxalinyl (quinoxalinyl), pyrazinyl, quinazolinyl, naphthyridinyl, benzothiophenyl, benzofuranyl, dibenzothiophenyl, arylthiazolyl ( arylthiazolyl), dibenzofuranyl, fluorenyl, carbazoyl, imidazolyl, carbolinyl, phenanthrenyl, terphenyl , terpyridinyl, triphenylenyl, fluoranthenyl, and diazafluorenyl.

In addition, L ₁ and L ₃ are each independently a single bond, substituted or unsubstituted phenylene, alkylphenylene, halophenylene, cyanophenylene, naph Tylene, alkylnaphthylene, biphenylene, alkylbiphenylene, pyridylene, pyrimidylene, quinolinylene, isoquinoly Nylene (isoquinolinylene), quinoxalinylene, pyrazinylene, quinazolinylene, naphthyridinylene, thiophenylene, furanylene, benzothiophenylene (benzothiophenylene), benzofuranylene, dibenzothiophenylene, dibenzofuranylene, fluorenylene, carbazoylene, imidazolylene, It is selected from triphenylenylene, fluoranthenylene and diazafluorenylene.

The compound represented by the above-mentioned Formula 1 may be represented by modeling as follows.

_{Here, phenanthroline corresponding to Ar 1} in Chemical Formula 1 is combined with an alkali metal doped into the N-type charge generation layer as a core to exhibit characteristics of the N-type charge generation layer. In more detail, the phenanthroline core contains ^{nitrogen (N) of sp 2} hybrid orbital, which is relatively rich in electrons, and this nitrogen binds to an alkali metal or alkaline earth metal that is a dopant of the N-type charge generating layer to form a gap state. (gap state) is formed. Therefore, by the formed gap state, electrons can be smoothly transferred from the N-type charge generation layer to the electron transport layer. In addition, since nitrogen is combined with an alkali metal or alkaline earth metal included in the N-type charge generation layer, the alkali metal or alkaline earth metal does not diffuse into the P-type charge generation layer, and thus lifespan can be improved.

A linker corresponding to _{L 1} and L ₂ in Formula 1 controls carrier mobility. L ₁ serves as a pathway for the abundant electrons of _{L 2 to reach Ar 1} through conjugation control, and controls the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). L ₂ improves the pi (π)-electron density through the introduction of an aromatic macrocycle, and serves to establish the main framework of HOMO and LUMO. Accordingly, by improving the charge mobility of the N-type charge generation layer, it is possible to smoothly transfer electrons from the N-type charge generation layer to the electron transport layer.

_{A pendant corresponding to L 3} -Ar ₂ and Ar ₃ of Formula 1 serves to add charge characteristics and controls HOMO and LUMO. For example, compounds represented by the following formula (2) impart hole properties, and compounds represented by formula (3) impart electronic properties. Pendants with electronic properties can improve the electronic properties of the N-type charge generation layer to facilitate the transfer of electrons from the N-type charge generation layer to the electron transport layer.

[Formula 2]

and Ar is aryl.

[Formula 3]

The aforementioned linker and pendant serve as a substituent on the core to improve the electron mobility of the compound. Therefore, the electron mobility of the N-type charge generation layer including the compound can be improved to facilitate the transfer of electrons from the N-type charge generation layer to the electron transport layer.

In addition, the N-type charge generation layer 160N according to the first embodiment of the present invention among the compounds represented by Formula 1 may be formed of a compound represented by Formula 4 or 5 below.

[Formula 4]

[Formula 5]

In Formulas 4 and 5, R is hydrogen, a substituted or unsubstituted aryl group having 6 to 60 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 60 carbon atoms, and an alkyl group having 1 to 20 carbon atoms.

The compound represented by Formulas 4 and 5 may be any one selected from the compounds represented below.

The compounds represented by Chemical Formulas 4 and 5 of the present invention described above have a structure in which naphthalene is positioned at the 2nd position of phenanthroline, and naphthalene is substituted with 1 or 2 positions. Naphthalene binds to the 2nd position of phenanthroline to reduce the energy level difference between the N-type charge generating layer and the electron transport layer, thereby maximizing the tunneling effect through which electrons can move. Therefore, in the present invention, by forming the compound as an N-type charge generating layer, the electron injection ability can be improved by the tunneling effect.

Meanwhile, the P-type charge generation layer 160P may be formed of a metal or an organic material doped with a P-type. Here, the metal may be made of one or two or more alloys selected from the group consisting of Al, Cu, Fe, Pb, Zn, Au, Pt, W, In, Mo, Ni and Ti. In addition, as the P-type dopant and the host material used in the P-type doped organic material, a commonly used material may be used. For example, the P-type dopant is F ₄ -TCNQ (2,3,5,6-tetrafluoro-7,7,8,8-tetracyanl-quinodemethane), a derivative of tetracyanoquinodimethane, iodine, FeCl ₃ , FeF ₃ and SbCl _{5 It} may be one material selected from the group consisting of. In addition, the host is NPB (N,N'-bis(naphthaen-1-yl)-N,N'-bis(phenyl)-benzidine), TPD (N,N'-bis(3-methylphenyl)N,N It may be one material selected from the group consisting of '-bis(phenyl)-benzidine) and TNB (N,N,N',N'-tetra-naphthalenyl-benzidine).

Meanwhile, the second light emitting unit ST2 including a second hole transport layer 180 , a second light emitting layer 190 , a second electron transport layer 200 , and an electron injection layer 210 on the first light emitting unit ST1 . ) is located. The second hole transport layer 180 and the second electron transport layer 200 may be configured the same as or different from the configuration of the first hole transport layer 130 and the first electron transport layer 150 of the first light emitting part ST1, respectively. have. The electron injection layer 210 may be omitted depending on the structure or characteristics of the device.

The second light emitting layer 190 may emit one color among red, green, and blue, and in this embodiment may be a yellow green light emitting layer that emits yellow-green. The yellow-green emission layer may have a single-layer structure of a yellow-green emission layer or a green emission layer, or a multi-layer structure of a yellow-green emission layer and a green emission layer. Here, the second light-emitting layer 190 is a yellow-green light-emitting layer or a green light-emitting layer or a yellow-green light-emitting layer and a green light-emitting layer or a yellow-green light-emitting layer and a red light-emitting layer or a green light-emitting layer and a red light-emitting layer or yellow. It includes a multilayer structure of a green light emitting layer and a red light emitting layer. In this embodiment, a single-layer structure of the second light emitting layer emitting yellow green will be described as an example. The second light emitting layer 190 is at least one selected from CBP (4,4'-bis(carbazol-9-yl)biphenyl) or BAlq (Bis(2-methyl-8-quinolinolate)-4-(phenylphenolato)aluminium) It may be formed of a phosphorescent yellow-green dopant that emits yellow-green light to the host. However, the present invention is not limited thereto.

The electron injection layer 210 serves to facilitate electron injection, and Alq ₃ (tris(8-hydroxy-quinolinato)aluminum), PBD(2-(4-biphenyl)-5-(4-tert-) butylphenyl)-1,3,4-oxadiazole), TAZ(3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole), and BAlq(Bis(2-methyl- 8-quinolinolate)-4-(phenylphenolato)aluminum) may be used, but is not limited thereto. On the other hand, the electron injection layer 210 may be formed of a metal compound, a metal compound, for example LiQ, LiF, NaF, KF, RbF, CsF, FrF, BeF _2, MgF _2, CaF _2, SrF _2, BaF ₂ And RaF _{2 It} may be any one or more selected from the group consisting of, but is not limited thereto. The electron injection layer 210 may have a thickness of 1 to 50 nm. Here, when the thickness of the electron injection layer 210 is 1 nm or more, there is an advantage in that the electron injection characteristic can be prevented from being deteriorated, and when it is 50 nm or less, the increase in the driving voltage is prevented by preventing an increase in the thickness of the electron injection layer 210 . can prevent

The second light emitting part ST2 includes a second hole transport layer 180 and the second light emitting layer 190 , and a second electron transport layer 200 and an electron injection layer 210 on the second light emitting layer 190 . includes Accordingly, the second light emitting unit ST2 including the second hole transport layer 180 , the second light emitting layer 190 , the second electron transport layer 200 , and the electron injection layer 210 on the first light emitting unit ST1 . make up

The cathode 220 is provided on the second light emitting part ST2 to configure the organic electroluminescent device according to the first embodiment of the present invention. The cathode 220 is an electron injection electrode, and may be made of magnesium (Mg), calcium (Ca), aluminum (Al), silver (Ag), or an alloy thereof having a low work function. Here, the cathode 220 may be formed to be thin enough to transmit light when the organic light emitting device has a front or double-sided light emitting structure, and when the organic light emitting device has a rear light emitting structure, it can reflect light. It can be formed as thick as possible.

As described above, the compound of the present invention has a structure in which a linker and a pendant are bonded to a phenanthroline core. Therefore, in the present invention, the nitrogen of the core of the compound is combined with the dopant to form a gap state, the charge mobility is improved by the linker, and the electronic properties are imparted by the pendant, thereby improving the electronic properties of the N-type charge generation layer. It is possible to facilitate the transfer of electrons from the type charge generating layer to the electron transport layer.

In addition, the compound of the present invention has a structure in which naphthalene is positioned at position 2 of phenanthroline, and naphthalene is substituted at position 1 or 2. Naphthalene binds to the 2nd position of phenanthroline to reduce the energy level difference between the N-type charge generating layer and the electron transport layer, thereby maximizing the tunneling effect through which electrons can move. Therefore, in the present invention, by forming the compound as an N-type charge generating layer, the electron injection ability can be improved by the tunneling effect.

Accordingly, in the present invention, by including a compound containing a nitrogen atom in the N-type charge generation layer, electrons can be efficiently transferred from the N-type charge generation layer to the electron transport layer, thereby improving device efficiency and device performance. In addition, since electrons are smoothly transferred from the N-type charge generating layer to the electron transport layer, the problem of a decrease in lifespan caused by poor electron injection can be improved. Further, it is possible to improve a problem in that a driving voltage generated when electrons injected into the N-type charge generation layer moves to the electron transport layer due to a difference in LUMO energy level between the electron transport layer and the N-type charge generation layer is increased.

Meanwhile, an organic electroluminescent device according to a second embodiment of the present invention will be described as follows. Since the structure of the organic light emitting diode according to the second embodiment of the present invention is the same as that of FIG. 1 , it will be described with reference to FIG. 1 , and descriptions overlapping those of the first embodiment will be simplified.

Referring to FIG. 1 , an organic light emitting diode 100 according to a second embodiment of the present invention includes light emitting units ST1 and ST2 and light emitting units ST1 and ST2 positioned between an anode 110 and a cathode 220 . ) and a charge generation layer 160 positioned between them. The first light emitting part ST1 includes the hole injection layer 120 and the first hole transport layer 130 between the anode 110 and the first light emitting layer 140 , and is located on the first light emitting layer 140 . 1 includes an electron transport layer 150 .

The charge generation layer 160 is positioned on the first light emitting part ST1. The charge generation layer 160 is a PN junction charge generation layer in which an N-type charge generation layer 160N and a P-type charge generation layer 160P are joined, and generates charges or separates them into holes and electrons to form holes and inject electrons

The N-type charge generation layer 160N of the charge generation layer 160 of the present invention may be made of the same compound as the N-type charge generation layer of the first embodiment described above. That is, the N-type charge generation layer 160N according to the second embodiment of the present invention may be composed of the compound represented by Formula 1 and the compounds represented by Formulas 4 and 5.

The compound of the present invention has a structure in which a linker and a pendant are bonded to a phenanthroline core. Therefore, in the present invention, the nitrogen of the core of the compound is combined with the dopant to form a gap state, the electron mobility is improved by the linker, and the electronic property is given by the pendant, thereby improving the electronic properties of the N-type charge generation layer. It is possible to facilitate the transfer of electrons from the type charge generating layer to the electron transport layer. In addition, the compound of the present invention has a structure in which naphthalene is positioned at position 2 of phenanthroline, and naphthalene is substituted at position 1 or 2. Naphthalene binds to the 2nd position of phenanthroline to reduce the energy level difference between the N-type charge generating layer and the electron transport layer, thereby maximizing the tunneling effect through which electrons can move. Therefore, in the present invention, by forming the compound as an N-type charge generating layer, the electron injection ability can be improved by the tunneling effect.

On the other hand, when the N-type charge generation layer 160N of the present invention is not formed of the above-described compound, it may be formed of a metal or an N-type doped organic material. Here, the metal may be one selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, La, Ce, Sm, Eu, Tb, Dy and Yb. In addition, as the N-type dopant and the host material used for the N-type doped organic material, a commonly used material may be used. For example, the N-type dopant may be an alkali metal, an alkali metal compound, an alkaline earth metal, or an alkaline earth metal compound. In detail, the N-type dopant may be one selected from the group consisting of Li, Cs, K, Rb, Mg, Na, Ca, Sr, Eu and Yb. The proportion of the dopant is mixed in an amount of 1 to 8% with respect to 100% of the entire host. Here, the work function of the dopant is preferably 2.5 eV or more. The host material may be an organic material having 20 or more and 60 or less carbon atoms having a heterocycle including a nitrogen atom, for example, tris(8-hydroxyquinoline)aluminum, triazine, hydroxyquinoline derivatives, and benzazole It may be one material selected from the group consisting of derivatives and silol derivatives.

Meanwhile, the second light emitting unit ST2 including a second hole transport layer 180 , a second light emitting layer 190 , a second electron transport layer 200 , and an electron injection layer 210 on the first light emitting unit ST1 . ) is located. The second electron transport layer 200 of the present invention serves to facilitate the transport of electrons, and when electrons are not smoothly transferred to the second light emitting layer 190, it affects the lifespan or efficiency of the organic light emitting diode. do. Accordingly, the inventors of the present invention conducted various experiments to improve the electron injection characteristics of the electron transport layer. A compound containing a nitrogen atom as an electron transport compound was introduced into the electron transport layer through various experiments on materials that do not affect the lifetime or efficiency of the organic light emitting diode and do not increase the driving voltage. The compound may include a phenanthroline compound. Since the compound of the present invention contains two nitrogen atoms and is rich in electrons, it has fast electron mobility to facilitate electron transport.

Accordingly, the second electron transport layer 200 is made of the compound represented by the above-described Chemical Formula 1. The compound represented by Formula 1 may be configured as follows, and the role in the N-type charge generation layer of the first embodiment of the present invention and the role in the second electron transport layer of the second embodiment of the present invention may be partially different have.

Here, _{phenanthroline corresponding to Ar 1} of Formula 1 contains two nitrogen atoms as a core and is rich in electrons, and thus has fast electron mobility to facilitate electron transport.

A linker corresponding to _{L 1} and L ₂ in Formula 1 controls carrier mobility. L ₁ serves as a pathway for the abundant electrons of _{L 2 to reach Ar 1} through conjugation control, and controls the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). L ₂ improves the pi (π)-electron density through the introduction of an aromatic macrocycle, and serves to establish the main framework of HOMO and LUMO. Accordingly, by improving the electron mobility of the first electron transport layer, it is possible to smoothly transfer electrons from the first electron transport layer to the first light emitting layer.

_{A pendant corresponding to L 3} -Ar ₂ and Ar ₃ of Formula 1 serves to add charge characteristics and controls HOMO and LUMO. For example, compounds represented by the following formula (2) impart hole properties, and compounds represented by formula (3) impart electronic properties. Pendants with electronic properties can improve the electronic properties of the N-type charge generation layer to facilitate the transfer of electrons from the N-type charge generation layer to the electron transport layer.

[Formula 2]

and Ar is aryl.

[Formula 3]

The above-mentioned linker and pendant serve as a substituent on the core to improve the electron mobility of the compound, and improve the electron mobility of the N-type charge generation layer containing the compound, thereby transferring electrons from the N-type charge generation layer to the electron transport layer. can facilitate the transmission of

The compound represented by Chemical Formula 1 that can be used in the second electron transport layer 200 of the present invention may be a compound shown in Table 1 below.

The compound of the present invention described above is included in the second light emitting part ST2 including the yellow green light emitting layer. The yellow green light emitting layer is a phosphorescent light emitting layer and requires an organic material layer with high electron mobility. The compound of the present invention has a fast electron mobility and a low triplet energy, so it is suitable for a phosphorescent light emitting layer. Therefore, when the compound of the present invention is included in the second light emitting part ST2, the electron mobility of the second light emitting part ST2 is increased. Therefore, the compound of the present invention is preferably located in the second light emitting part ST2 that emits phosphorescent yellow green. In addition, when the phosphorescent light emitting layer is positioned in the first light emitting part ST1 or the phosphorescent light emitting layer is positioned in the third light emitting part ST3 , the compound of the present invention is applied to the first light emitting part ST1 or the third light emitting part ST1 . It may be located at (ST3).

The second electron transport layer 200 according to the second embodiment of the present invention includes the compound of the present invention to have fast electron mobility to facilitate the transport of electrons and to facilitate the transport of electrons from the electron transport layer to the light emitting layer. . Accordingly, in the organic electroluminescent device according to the second embodiment of the present invention, the first light emitting part ST1, the charge generating layer 160 and the second light emitting part ST2 are formed between the anode 100 and the cathode 220 . and constitutes an organic electroluminescent device.

In the second embodiment of the present invention described above, it has been described that the compound of the present invention is included in the N-type charge generating layer 160N and the second electron transporting layer 200 of the charge generating layer, but the present invention is not limited thereto. At least one of the N-type charge generation layer 160N of (150), the second electron transport layer 200 and the charge generation layer 160 may be formed of the compound of the present invention.

As described above, the compound containing a nitrogen atom of the present invention is rich in electrons by including two nitrogen atoms, and thus has a fast electron mobility to facilitate electron transport. Accordingly, in the organic light emitting device of the present invention, by using a compound in at least one of the electron transport layers included in the light emitting part, the electrons transferred from the N-type charge generating layer are efficiently transferred to the light emitting layer.

In addition, the compound containing a nitrogen atom of the present invention contains ^{nitrogen (N) of sp 2} hybrid orbital, which is relatively rich in electrons, and this nitrogen is bound to an alkali metal or alkaline earth metal as a dopant in the N-type charge generating layer. ) to form a gap state. By the formed gap state, it is possible to smoothly transfer electrons from the N-type charge generation layer to the electron transport layer. Accordingly, in the organic electroluminescent device of the present invention, by using the compound of the present invention in the N-type charge generating layer, electrons can be smoothly transferred from the N-type charge generating layer to the electron transporting layer. In addition, since the compound containing the nitrogen atom is combined with the alkali metal or alkaline earth metal included in the N-type charge generating layer, the alkali metal or alkaline earth metal does not diffuse into the P-type charge generating layer, and thus the lifespan may be improved.

Accordingly, the organic electroluminescent device of the present invention uses a compound containing a nitrogen atom in at least one of the electron transporting layers and the N-type charge generating layers included in the light emitting part, so that electrons transferred from the N-type charge generating layer are transferred to the light emitting layer. It is possible to improve device efficiency and device performance by efficiently transferring it to In addition, since electrons are smoothly transferred from the N-type charge generating layer to the electron transport layer, the problem of a decrease in lifespan caused by poor electron injection can be improved. Further, it is possible to improve a problem in that a driving voltage generated when electrons injected into the N-type charge generation layer moves to the electron transport layer due to a difference in LUMO energy level between the electron transport layer and the N-type charge generation layer is increased.

2 is a view showing an organic electroluminescent device according to a third embodiment of the present invention. Hereinafter, the same reference numerals are assigned to the same components as those of the above-described first and second embodiments, and descriptions thereof will be omitted.

Referring to FIG. 2 , the organic light emitting device 100 of the present invention includes a plurality of light emitting units ST1 , ST2 , ST3 and a plurality of light emitting units ST1 and ST2 positioned between the anode 110 and the cathode 220 . , ST3) and a first charge generation layer 160 and a second charge generation layer 230 positioned between. In the present embodiment, it has been illustrated and described that three light emitting units are positioned between the anode 110 and the cathode 220 , but the present invention is not limited thereto and four or more light emitting units are disposed between the anode 110 and the cathode 220 . may include

In more detail, the first light emitting unit ST1 constitutes one light emitting device unit and includes the first light emitting layer 140 . The first light emitting layer 140 may emit any one of red, green, and blue, and in the present embodiment may be a blue light emitting layer that emits blue. The blue light emitting layer includes one of a blue light emitting layer, a dark blue light emitting layer, or a sky blue light emitting layer. In this case, the light emitting area of the blue light emitting layer, the dark blue light emitting layer, or the sky blue light emitting layer may be in the range of 440 nm to 480 nm. Alternatively, the first light emitting layer 140 may include a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a green light emitting layer. The emission area of the blue emission layer and the red emission layer may be in a range of 440 nm to 650 nm. In addition, the light emitting area of the blue light emitting layer and the yellow-green light emitting layer may be in a range of 440 nm to 590 nm. In addition, the light emitting area of the blue light emitting layer and the green light emitting layer may be in a range of 440 nm to 570 nm.

The first light emitting part ST1 includes a hole injection layer 120 and a first hole transport layer 130 between the anode 110 and the first light emitting layer 140 , and includes a first light emitting layer 140 on the first light emitting layer 140 . and an electron transport layer 150 . Accordingly, the first light emitting part ST1 including the hole injection layer 120 , the first hole transport layer 130 , the first light emitting layer 140 , and the first electron transport layer 150 on the anode 110 is configured. . The hole injection layer 120 may not be included in the configuration of the first light emitting part ST1 depending on the structure or characteristics of the device.

A first charge generation layer 160 is positioned between the first light emitting part ST1 and the second light emitting part ST2 . The first charge generation layer 160 is a PN junction charge generation layer in which an N-type charge generation layer 160N and a P-type charge generation layer 160P are joined, and generates charges or separates them into holes and electrons in each light emitting layer. Holes and electrons are injected.

The N-type charge generation layer 160N of the first charge generation layer 160 of the present invention may be made of the same compound as the N-type charge generation layer of the first embodiment and the N-type charge generation layer of the second embodiment. That is, the N-type charge generation layer 160N according to the third embodiment of the present invention may be composed of the compound represented by Formula 1 and the compounds represented by Formulas 2 and 3.

The compound of the present invention has a structure in which a linker and a pendant are bonded to a phenanthroline core. Therefore, in the present invention, the nitrogen of the core of the compound is combined with the dopant to form a gap state, the charge mobility is improved by the linker, and the electronic properties are imparted by the pendant, thereby improving the electronic properties of the N-type charge generation layer. It is possible to facilitate the transfer of electrons from the type charge generating layer to the electron transport layer. In addition, the compound of the present invention has a structure in which naphthalene is positioned at position 2 of phenanthroline, and naphthalene is substituted at position 1 or 2. Naphthalene binds to the 2nd position of phenanthroline to reduce the energy level difference between the N-type charge generating layer and the electron transport layer, thereby maximizing the tunneling effect through which electrons can move. Therefore, in the present invention, by forming the compound as an N-type charge generating layer, the electron injection ability can be improved by the tunneling effect.

Meanwhile, the second light emitting part ST2 including the second light emitting layer 190 is positioned on the first charge generating layer 160 . The second light emitting layer 190 may emit one color among red, green, and blue. For example, in the present embodiment, the second light emitting layer 190 may be a yellow green light emitting layer that emits yellow-green. The yellow-green light-emitting layer includes a yellow light-emitting layer or a green light-emitting layer or a yellow-green light-emitting layer and a green light-emitting layer or a yellow light-emitting layer and a red light-emitting layer or a green light-emitting layer and a red light-emitting layer or a yellow-green light-emitting layer and a red light-emitting layer. It can be made of a multi-layer structure of In addition, the emission area of the yellow-green emission layer may be in the range of 510 nm to 590 nm. In order to improve red efficiency, when the second light emitting layer 190 is composed of two light emitting layers of a yellow-green light emitting layer and a red light emitting layer, a yellow-green light emitting layer and a red light emitting layer are formed. The light emitting area of the light emitting layer may range from 510 nm to 650 nm.

The second light emitting part ST2 includes the second hole transport layer 180 and the second light emitting layer 190 , and includes a second electron transport layer 200 on the second light emitting layer 190 . Accordingly, the second light emitting part ST2 including the second hole transport layer 180 , the second emission layer 190 , and the second electron transport layer 200 is formed on the first charge generation layer 160 .

A second charge generation layer 230 is positioned between the second light emitting part ST2 and the third light emitting part ST3 . The second charge generation layer 230 is a PN junction charge generation layer in which an N-type charge generation layer 230N and a P-type charge generation layer 230P are joined, and generates charges or separates them into holes and electrons in each of the light emitting layers. Holes and electrons are injected. The N-type charge generation layer 230N of the second charge generation layer 230 of the present invention is also a compound represented by Formula 1 in the same manner as the N-type charge generation layer 160N of the first charge generation layer 160 described above. is done

A third light emitting part ST3 including a third light emitting layer 250 is positioned on the second light emitting part ST2 . The third light-emitting layer 250 may emit one color among red, green, and blue, for example, a blue light-emitting layer that emits blue in the present embodiment. The blue light emitting layer includes one of a blue light emitting layer, a dark blue light emitting layer, or a sky blue light emitting layer. In this case, the light emitting area of the blue light emitting layer, the dark blue light emitting layer, or the sky blue light emitting layer may be in the range of 440 nm to 480 nm. Alternatively, the first light emitting layer 140 may include a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a green light emitting layer. The emission area of the blue emission layer and the red emission layer may be in a range of 440 nm to 650 nm. In addition, the light emitting area of the blue light emitting layer and the yellow-green light emitting layer may be in a range of 440 nm to 590 nm. In addition, the light emitting area of the blue light emitting layer and the green light emitting layer may be in a range of 440 nm to 570 nm.

The third light emitting part ST3 includes a third hole transport layer 240 and the third light emitting layer 250 , and a third electron transport layer 260 and an electron injection layer 210 on the third light emitting layer 250 . includes Accordingly, the third light emitting part ST3 including the third hole transport layer 240 , the third emission layer 250 , the third electron transport layer 260 , and the electron injection layer 210 on the second charge generation layer 230 . ) constitutes The cathode 220 is provided on the third light emitting part ST3 to configure the organic electroluminescent device according to the third embodiment of the present invention.

In the third embodiment of the present invention described above, it has been described that the compound is included in the N-type charge generation layer 160N of the first charge generation layer and the N-type charge generation layer 230N of the second charge generation layer, but the present invention is limited thereto. At least one of the N-type charge generation layer 160N of the first charge generation layer 160 and the N-type charge generation layer 230N of the second charge generation layer 230N may be formed of the compound of the present invention. .

As described above, the compound of the present invention has a structure in which a linker and a pendant are bonded to a phenanthroline core. Therefore, in the present invention, the nitrogen of the core of the compound is combined with the dopant to form a gap state, the charge mobility is improved by the linker, and the electronic properties are imparted by the pendant, thereby improving the electronic properties of the N-type charge generation layer. It is possible to facilitate the transfer of electrons from the type charge generating layer to the electron transport layer.

In addition, the compound of the present invention has a structure in which naphthalene is positioned at position 2 of phenanthroline, and naphthalene is substituted at position 1 or 2. Naphthalene binds to the 2nd position of phenanthroline to reduce the energy level difference between the N-type charge generating layer and the electron transport layer, thereby maximizing the tunneling effect through which electrons can move. Therefore, in the present invention, by forming the compound as an N-type charge generating layer, the electron injection ability can be improved by the tunneling effect.

Accordingly, in the present invention, by including a compound containing a nitrogen atom in the N-type charge generation layer, electrons can be efficiently transferred from the N-type charge generation layer to the electron transport layer, thereby improving device efficiency and device performance. In addition, since electrons are smoothly transferred from the N-type charge generating layer to the electron transport layer, the problem of a decrease in lifespan caused by poor electron injection can be improved. Further, it is possible to improve a problem in that a driving voltage generated when electrons injected into the N-type charge generation layer moves to the electron transport layer due to a difference in LUMO energy level between the electron transport layer and the N-type charge generation layer is increased.

Meanwhile, an organic electroluminescent device according to a fourth embodiment of the present invention will be described as follows. Since the structure of the organic light emitting diode according to the fourth embodiment of the present invention is the same as that of FIG. 2 , it will be described with reference to FIG. 2 , and descriptions overlapping those of the first to third embodiments will be simplified.

Referring to FIG. 2 , the organic light emitting diode 100 according to the fourth embodiment of the present invention includes a plurality of light emitting units ST1 , ST2 , ST3 positioned between an anode 110 and a cathode 220 , and a plurality of A first charge generation layer 160 and a second charge generation layer 230 are positioned between the light emitting units ST1 , ST2 , and ST3 . In the present embodiment, it has been illustrated and described that three light emitting units are positioned between the anode 110 and the cathode 220 , but the present invention is not limited thereto and four or more light emitting units are disposed between the anode 110 and the cathode 220 . may include

In more detail, the first light emitting unit ST1 constitutes one light emitting device unit and includes the first light emitting layer 140 . The first light emitting layer 140 may emit any one of red, green, and blue, and in the present embodiment may be a blue light emitting layer that emits blue. The blue light emitting layer includes one of a blue light emitting layer, a dark blue light emitting layer, or a sky blue light emitting layer. In this case, the light emitting area of the blue light emitting layer, the dark blue light emitting layer, or the sky blue light emitting layer may be in the range of 440 nm to 480 nm. Alternatively, the first light emitting layer 140 may include a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a green light emitting layer. The emission area of the blue emission layer and the red emission layer may be in a range of 440 nm to 650 nm. In addition, the light emitting area of the blue light emitting layer and the yellow-green light emitting layer may be in a range of 440 nm to 590 nm. In addition, the light emitting area of the blue light emitting layer and the green light emitting layer may be in a range of 440 nm to 570 nm.

The first light emitting part ST1 includes a hole injection layer 120 and a first hole transport layer 130 between the anode 110 and the first light emitting layer 140 , and includes a first light emitting layer 140 on the first light emitting layer 140 . and an electron transport layer 150 . Accordingly, the first light emitting part ST1 including the hole injection layer 120 , the first hole transport layer 130 , the first light emitting layer 140 , and the first electron transport layer 150 on the anode 110 is configured. . The hole injection layer 120 may not be included in the configuration of the first light emitting part ST1 depending on the structure or characteristics of the device.

A first charge generation layer 160 is positioned between the first light emitting part ST1 and the second light emitting part ST2 . The first charge generation layer 160 is a PN junction charge generation layer in which an N-type charge generation layer 160N and a P-type charge generation layer 160P are joined, and generates charges or separates them into holes and electrons in each light emitting layer. Holes and electrons are injected.

The N-type charge generation layer 160N of the first charge generation layer 160 of the present invention is made of a compound represented by Formula 1 in the same manner as in the first to third embodiments described above. The compound represented by Formula 1 of the present invention has a structure in which a linker and a pendant are bonded to a phenanthroline core. Therefore, the compound of the present invention forms a gap state by combining nitrogen of the core with an alkali metal or alkaline earth metal contained in the N-type charge generating layer, improving charge mobility by a linker, and imparting electronic properties by a pendant, By improving the electronic properties of the N-type charge generation layer, electrons can be smoothly transferred from the N-type charge generation layer to the electron transport layer. In addition, since nitrogen is combined with an alkali metal or alkaline earth metal included in the N-type charge generation layer, the alkali metal or alkaline earth metal does not diffuse into the P-type charge generation layer, and thus lifespan can be improved.

Meanwhile, the second light emitting part ST2 including the second light emitting layer 190 is positioned on the first charge generating layer 160 . The second light emitting layer 190 may emit one color among red, green, and blue. For example, in the present embodiment, the second light emitting layer 190 may be a yellow green light emitting layer that emits yellow-green. The yellow-green light-emitting layer includes a yellow-green light-emitting layer or a green light-emitting layer or a yellow-green light-emitting layer and a green light-emitting layer or a yellow light-emitting layer and a red light-emitting layer or a green light-emitting layer and a red light-emitting layer or yellow. It may have a multilayer structure of a green light emitting layer and a red light emitting layer. The light emitting area of the yellow green light emitting layer may be in the range of 510 nm to 590 nm. And, in order to improve red efficiency, when the second light emitting layer 190 is composed of two light emitting layers of a yellow-green light emitting layer and a red light emitting layer, a yellow-green light emitting layer and a red light emitting layer Red) The emission area of the emission layer may be in the range of 510 nm to 650 nm.

The second light emitting part ST2 further includes a second hole transport layer 180 , and includes a second electron transport layer 200 on the second light emitting layer 190 . Accordingly, the second light emitting unit ST2 including the second hole transport layer 180 , the second light emitting layer 190 , and the second electron transport layer 200 is formed on the first light emitting unit ST1 .

The second electron transport layer 200 of the present invention is made of a compound represented by Chemical Formula 1 in the same manner as in the second embodiment described above. The compound represented by Formula 1 of the present invention has a structure in which a linker and a pendant are bonded to a phenanthroline core. Accordingly, the second electron transport layer 200 according to the fourth embodiment of the present invention has a fast electron mobility to facilitate electron transport.

A second charge generation layer 230 is positioned between the second light emitting part ST2 and the third light emitting part ST3 . The second charge generation layer 230 is a PN junction charge generation layer in which an N-type charge generation layer 230N and a P-type charge generation layer 230P are joined, and generates charges or separates them into holes and electrons in each of the light emitting layers. Holes and electrons are injected.

The N-type charge generation layer 230N of the second charge generation layer 230 of the present invention is also a compound represented by Formula 1 in the same manner as the N-type charge generation layer 160N of the first charge generation layer 160 described above. is done The compound represented by Formula 1 of the present invention has a structure in which a linker and a pendant are bonded to a phenanthroline core. Therefore, in the compound of the present invention, the nitrogen of the core combines with the dopant to form a gap state, the charge mobility is improved by the linker, and the electronic properties are imparted by the pendant, thereby improving the electronic properties of the N-type charge generation layer. It is possible to facilitate the transfer of electrons from the type charge generating layer to the electron transport layer.

A third light emitting part ST3 including a third light emitting layer 250 is positioned on the second light emitting part ST2 . The third light-emitting layer 250 may emit one color among red, green, and blue, for example, a blue light-emitting layer that emits blue in the present embodiment. The blue light emitting layer includes one of a blue light emitting layer, a dark blue light emitting layer, or a sky blue light emitting layer. Alternatively, the first light emitting layer 140 may include a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a green light emitting layer.

The third light emitting part ST3 includes a third hole transport layer 240 , and includes a third electron transport layer 260 and an electron injection layer 210 on the third emission layer 250 . Accordingly, the third light emitting unit ST3 including the third hole transport layer 240 , the third light emitting layer 250 , the third electron transport layer 260 , and the electron injection layer 210 on the second light emitting unit ST2 . make up A cathode 220 is provided on the third light emitting part ST3 to configure the organic electroluminescent device according to the fourth embodiment of the present invention.

In the fourth embodiment of the present invention described above, the compound is added to the N-type charge generation layer 160N of the first charge generation layer, the N-type charge generation layer 230N of the second charge generation layer, and the second electron transport layer 200. Although described as including, it is not limited thereto. The first electron transport layer 150 , the N-type charge generation layer 160N of the first charge generation layer 160 , the N-type charge generation layer 230N of the second charge generation layer 230N, and the third electron transport layer 260 ) of at least one or more of the compound of the present invention may be formed.

As described above, the compound containing a nitrogen atom of the present invention is rich in electrons by including two nitrogen atoms, and thus has a fast electron mobility to facilitate electron transport. Accordingly, in the organic light emitting device of the present invention, by using a compound in at least one of the electron transport layers included in the light emitting part, the electrons transferred from the N-type charge generating layer are efficiently transferred to the light emitting layer.

In addition, the compound containing a nitrogen atom of the present invention contains ^{nitrogen (N) of sp 2} hybrid orbital, which is relatively rich in electrons, and this nitrogen is bound to an alkali metal or alkaline earth metal as a dopant in the N-type charge generating layer. ) to form a gap state. By the formed gap state, it is possible to smoothly transfer electrons from the N-type charge generation layer to the electron transport layer. Accordingly, in the organic electroluminescent device of the present invention, by using the compound of the present invention in the N-type charge generating layer, electrons can be smoothly transferred from the N-type charge generating layer to the electron transporting layer. In addition, since nitrogen is combined with an alkali metal or alkaline earth metal included in the N-type charge generation layer, the alkali metal or alkaline earth metal does not diffuse into the P-type charge generation layer, and thus lifespan can be improved.

Accordingly, the organic electroluminescent device of the present invention uses a compound containing a nitrogen atom in at least one of the electron transporting layers and the N-type charge generating layers included in the light emitting part, so that electrons transferred from the N-type charge generating layer are transferred to the light emitting layer. It is possible to improve device efficiency and device performance by efficiently transferring it to In addition, since electrons are smoothly transferred from the N-type charge generating layer to the electron transport layer, the problem of a decrease in lifespan caused by poor electron injection can be improved. Further, it is possible to improve a problem in that a driving voltage generated when electrons injected into the N-type charge generation layer moves to the electron transport layer due to a difference in LUMO energy level between the electron transport layer and the N-type charge generation layer is increased.

Hereinafter, synthetic examples of the compounds of the present invention will be described in detail in the following Examples. However, the following examples illustrate the present invention, and the present invention is not limited to the following examples.

<Experiment 1>

Synthesis example

1) Synthesis of Intermediate A

In a round-bottom flask, 1-(1-bromonaphthalen-4-yl)ethanone (1-(1-bromonaphthalen-4-yl)ethanone) (14.5 g, 0.058 mol), 8-aminoquinoline-7-carbaldehyde (8-aminoquinoline-7-carbaldehyde) (10 g, 0.058 mol), 800 ml of ABS ethanol (Absolute EtOH), 13 g of potassium hydroxide (KOH) were added, the temperature was raised to reflux, and the mixture was stirred for 15 hours. After the reaction solution is cooled to room temperature, the organic layer is recovered by extraction with _{dichloromethane (CH 2} Cl _{2 , MC)/water.} After the organic layer was concentrated under reduced pressure, _{dichloromethane was developed using aluminum oxide (Al 2} O ₃ ), followed by column separation to obtain 10.5 g of Intermediate A.

2) Synthesis of compound NC09 (2-4, biphenyl-3-yl-naphthalene-1-yl-1,10-phenanthroline)

In a round-bottom flask, 2-Bromo-1,10-phenanthroline (3 g, 0.012 mol), 4-biphenyl-3-yl-naphthalene-1-boronic acid ( 4-biphenyl-3-yl-naphthalene-1-boronic acid) (4.5 g, 0.014 mol), tetrakis (triphenylphosphine) palladium (0) (Tetrakis (triphenylphosphine) palladium (0) (0.5 g, 0.5 mmol) ), toluene (Toluene) 60ml, ethanol (EtOH) 15ml, 2M potassium carbonate (K ₂ CO ₃ ) 12ml was added, and refluxed and stirred for 12 hours After completion of the reaction, the organic layer was extracted, extracted and concentrated under reduced pressure to remove the solvent A silica gel column (MC→MC:Acetone=10:1) was separated and concentrated under reduced pressure to obtain 3.2 g of compound NC09.

3) Synthesis of compound NC12 (2-(1-(10-phenylanthracen-9-yl)naphthalen-4-yl)-1,10-phenanthroline)

In a round-bottom flask, 3 g (8 mmol) of Intermediate A, 9-phenylanthracene-10-boronic acid (2.8 g, 9 mmol), tetrakis (triphenylphosphine) palladium (0) ( 0.4g, 0.3mmol), toluene 60ml, ethanol 15ml, 2M potassium carbonate 8ml, and stirred under reflux for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude product was _{dissolved by heating in chloroform (CHCl 3} ), filtered under reduced pressure over aluminum oxide (Al ₂ O ₃ ), concentrated and recrystallized to obtain 2 g of NC12 compound.

4) Synthesis of compound NC17 (2-(1-(quinolin-2-yl)naphthalen-4-yl)-1,10-phenanthroline)

Intermediate A (3g, 8mmol), 9-phenylanthracene-10-boronic acid (1.6g, 9mmol), tetrakis(triphenylphosphine)palladium(0)(0.4g, 0.3mmol), toluene 60ml in a round bottom flask , ethanol 15ml, 2M potassium carbonate (K ₂ CO ₃ ) 8ml was added and stirred under reflux for 12 hours. After completion of the reaction, the organic layer was recovered by extraction, concentrated under reduced pressure to remove the solvent, and then separated by silica gel column (MC→MC:Acetone=10:1) using _{aluminum oxide (Al 2} O _{3 ).} Concentration under reduced pressure gave 2.4 g of compound NC17.

5) Synthesis of Intermediate B (2-(2-bromonaphthalen-6-yl)-1,10-phenanthroline)

In a round-bottom flask, 1- (2-bromonaphthalen-4-yl) ethanone (1- (2-bromonaphthalen-4-yl) ethanone) (7.3 g, 0.029 mol), 8-aminoquinoline-7-carbaldehyde (5 g, 0.029 mol), 400 ml of ABS ethanol, and 6.5 g of potassium hydroxide (KOH) were added, the temperature was raised to reflux, and the mixture was stirred for 15 hours. After the reaction solution is cooled to room temperature, the organic layer is recovered by extraction with dichloromethane/water. After the organic layer was concentrated under reduced pressure, _{dichloromethane was developed using aluminum oxide (Al 2} O ₃ ) and column separation was performed to obtain 4.6 g of Intermediate B.

6) Synthesis of compound NC34 (2-(2-(pyren-1-yl)naphthalen-6-yl)-1,10-phenanthroline)

Intermediate B (3g, 8mmol), pyrene-1-boronic acid (2.3g, 9mmol), tetrakis(triphenylphosphine)palladium(0)(0.4g, 0.3mmol), toluene 60ml, ethanol 15ml in a round bottom flask , 2M potassium carbonate (K ₂ CO ₃ ) 8ml was added and stirred under reflux for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure over aluminum oxide, concentrated and recrystallized to obtain 1.6 g of NC34 compound.

7) Synthesis of compound NC42 (2-(1-(10-(4-tert-butylphenyl)anthracene-9-yl)naphthalen-4-yl)-1,10-phenanthroline)

Intermediate A (3g, 8mmol), 9-(4-tert-butylphenyl)anthracen-10-yl-10-boronic acid (9-(4-tert-butylphenyl)anthracene-10-yl-10- boronic acid) (3.3g, 9mmol), tetrakis(triphenylphosphine)palladium(0)(0.4g, 0.3mmol), toluene 60ml, ethanol 15ml, 2M K2CO3 8ml were added and stirred under reflux for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure over aluminum oxide, concentrated and recrystallized to obtain 2.4 g of NC42 compound.

8) Synthesis of compound NC43 (2-(1-(3-(10-(4-tert-butylphenyl)anthracene-9-yl)phenyl)naphthalen-4-yl)-1,10-phenanthroline)

Intermediate A (3 g, 8 mmol), 9-phenylanthracene-10-boronic acid (4 g, 9 mmol), tetrakis (triphenylphosphine) palladium (0) (0.4 g, 0.3 mmol), toluene 60 ml, Ethanol 15ml, 2M potassium carbonate (K ₂ CO ₃ ) 8ml was added and stirred under reflux for 12 hours. After completion of the reaction, the organic layer was recovered by extraction, concentrated under reduced pressure to remove the solvent, and then separated by silica gel column (MC→MC:Acetone=10:1) using _{aluminum oxide (Al 2} O _{3 ).} Concentration under reduced pressure gave 2.4 g of compound NC43.

In order to check the thermal stability of the prepared compounds, the glass transition temperature (Tg) and the melting point (Tm) of the compounds NC09, NC12, NC17, NC34, NC42 and NC43 were measured and shown in FIGS. It is summarized in 2. The glass transition temperature (Tg) and the melting point (Tm) were measured by the DSC (Differential Scanning Calorimeter) method. DSC measures the change in thermal energy according to temperature change and is used in the study of polymer materials. 3 is a graph showing the glass transition temperature of compound NC09. 4 is a graph showing the glass transition temperature of compound NC12. 5 is a graph showing the melting point of compound NC12. 6 is a graph showing the glass transition temperature of compound NC17, and FIG. 7 is a graph showing the melting point of compound NC17. 8 is a graph showing the glass transition temperature of compound NC34. 9 is a graph showing the glass transition temperature of compound NC42, and FIG. 10 is a graph showing the melting point of compound NC42. 11 is a graph showing the glass transition temperature of compound NC43, and FIG. 12 is a graph showing the melting point of compound NC43. (For reference, in the case of NC09 and NC34, the melting point was not measured.) In FIGS. 3 to 12 , the horizontal axis indicates temperature, and the vertical axis indicates heat flow.

compound Glass transition temperature (Tg, ℃) Melting point (Tm, ℃) NC09 101.05 - NC12 185.39 347.44 NC17 114.25 251.00 NC34 156.84 - NC42 199.64 375.46 NC43 167.31 352.35

3 is a graph showing the glass transition temperature of compound NC09. As shown in FIG. 3 , there is a portion in which the heat flow of the vertical axis changes at a certain temperature. The glass transition temperature is determined as the intermediate value between the temperature at which the heat flow starts and the temperature at which the change ends. Therefore, it can be seen that the glass transition temperature (Tg) of NC09 is 101.05°C. In addition, the melting point of NC09 was not measured.

5 is a graph showing the melting point of compound NC12. The melting point (Tm) refers to the temperature at which the glass transition temperature appears when the temperature is raised to a constant temperature and then absorbs heat at a specific temperature and another peak appears. Therefore, it can be seen that the melting point (Tm) of NC12 is 347.44 °C.

Referring to FIGS. 3 to 12 and Table 2, the compounds of the present invention prepared in Synthesis Examples exhibit a glass transition temperature of about 100° C. or higher and a melting point of 250° C. or higher, so that the compounds of the present invention are organic electroluminescent devices. It can be confirmed that it can have thermal stability when applied to

Hereinafter, an embodiment in which an organic electroluminescent device is fabricated using the above-described compound as an N-type charge generating layer is disclosed. The thickness or formation conditions of the following organic layers do not limit the scope of the present invention.

comparative example

After patterning so that the emission area of the ITO substrate has a size of 2 mm × 2 mm, it was washed with UV ozone. After the substrate was mounted in a vacuum chamber, the base pressure was set to 5-7x10 ^-8 torr, and the following layers were deposited by evaporation from a heating boat in the following order.

_{(1) Doping F 4} -TCNQ in 10% of NPD as a hole injection layer to form a thickness of 100 Å,

(2) forming NPD with a thickness of 1200 Å as a hole transport layer,

(3) doping an anthracene host with 4% pyrene dopant as a blue light emitting layer to form a thickness of 200 Å,

(4) TmPyPB as a first electron transport layer to a thickness of 100 Å,

(5) Doping BPhen with 2% Li as an N-type charge generation layer to form a thickness of 100 Å,

(6) as a P-type charge generation layer _{, doping NPD with F 4} -TCNQ at 10% to form a thickness of 200 Å,

(7) forming NPD to a thickness of 200 Å as a hole transport layer,

(8) doping the CBP host with 10% Ir compound as a yellow light emitting layer to form a thickness of 200 Å,

_{(9) forming Alq 3} to a thickness of 100 Å as a second electron transport layer,

(10) Forming LiF to a thickness of 5 Å as an electron injection layer,

(11) Al was formed to a thickness of 2000 Å as a cathode.

After deposition of these layers, they were transferred from the deposition chamber into a drying box for film formation, and subsequently encapsulated using UV-curing epoxy and moisture getter to fabricate an organic electroluminescent device.

Example 1

In the same configuration as in the aforementioned comparative example, the N-type charge generation layer was formed of compound NC09.

Example 2

In the same configuration as in the aforementioned comparative example, the N-type charge generation layer was formed of compound NC12.

Example 3

In the same configuration as in the aforementioned comparative example, the N-type charge generation layer was formed of compound NC17.

Example 4

In the same configuration as in the aforementioned comparative example, the N-type charge generating layer was formed of compound NC34.

Example 5

In the same configuration as in the aforementioned comparative example, the N-type charge generation layer was formed of compound NC42.

Example 6

In the same configuration as in the aforementioned comparative example, the N-type charge generation layer was formed of compound NC43.

The material of the n-type charge generation layer in the above comparative examples and examples does not limit the content of the present invention.

The driving voltage, current efficiency, and lifespan of the organic light emitting diodes manufactured according to Comparative Examples and Examples 1 to 6 were measured and shown in Table 3 below. In addition, the current density according to the driving voltage was measured and shown in FIG. 13 , the emission spectrum was measured and shown in FIG. 14 , and the rate of decrease in luminance with time was measured and shown in FIG. 15 . In addition, in Table 3 below, the result value of the comparative example is 100%, and the result value of the remaining examples is shown as a ratio. In addition, as for the lifetime T95, the time to reach the luminance of 95% compared to the initial luminance of 100% is shown in comparison with the comparative example.

Driving voltage (%) Current efficiency (%) Lifetime (T95)(%) comparative example 100 100 100 Example 1 94 104 119 Example 2 103 105 124 Example 3 94 101 85 Example 4 93 102 128 Example 5 91 102 108 Example 6 105 102 243

13 to 15 and Table 3, compared to the comparative example in which BPhen was used for the N-type charge generation layer in the stack structure, Example 1 in which the compound NC09 was used for the N-type charge generation layer had a driving voltage of 6% lowered, the current efficiency increased by 4%, and the service life was increased by 19%. In addition, in Example 2, in which the compound NC12 was used for the N-type charge generation layer, compared to the comparative example, the driving voltage was increased by 3%, but the current efficiency was increased by 5% and the lifespan was increased by 24%. In addition, compared to Comparative Example, Example 3 using compound NC17 for the N-type charge generation layer increased the lifetime by 15%, but decreased the driving voltage by 6% and increased the current efficiency by 1%. In addition, compared to Comparative Example, Example 4 using compound NC34 for the N-type charge generation layer decreased the driving voltage by 7%, increased the current efficiency by 2%, and increased the lifespan by 28%. In addition, in Example 5, in which the compound NC42 was used for the N-type charge generation layer, compared to the comparative example, the driving voltage was decreased by 9%, the current efficiency was increased by 2%, and the lifetime was increased by 8%. In addition, compared to Comparative Example, Example 6 in which compound NC43 was used for the N-type charge generation layer increased the driving voltage by 5%, but the current efficiency increased by 2% and the lifespan increased by 143%.

<Experiment 2>

Synthesis example

1) Synthesis of Intermediate C(2-(1-bromonaphthalen-4-yl)-1,10-phenanthroline)

In a round-bottom flask, 1- (1-bromonaphthalen-4-yl) ethanone (1- (1-bromonaphthalen-4-yl) ethanone) (14.5 g, 0.058 mol), 8-aminoquinoline-7-carbaldehyde (8-aminoquinoline-7-carbaldehyde) (10 g, 0.058 mol), 800 ml of ABS ethanol, and 13 g of KOH were added, the temperature was raised to reflux, and the mixture was stirred for 15 hours. After the reaction solution is cooled to room temperature, the organic layer is recovered by extraction with dichloromethane/water. After the organic layer was concentrated under reduced pressure, _{dichloromethane was developed using Al 2} O ₃ and column separation was performed to obtain 10.5 g of Intermediate C.

2) Synthesis of intermediate D (2-(3-bromophenyl)-1,10-phenanthroline)

In a round bottom flask, 1- (3-bromophenyl) ethanone (15 g, 0.075 mol), 8-aminoquinoline-7-carbaldehyde (8-aminoquinoline-7-carbaldehyde) (13g, 0.075mol), 800ml of ABS ethanol, and 15g of KOH were added, the temperature was raised to reflux, and the mixture was stirred for 15 hours. After the reaction solution is cooled to room temperature, the organic layer is recovered by extraction with dichloromethane/water. After the organic layer was concentrated under reduced pressure, _{dichloromethane was developed using Al 2} O ₃ and column separation was performed to obtain 13.7 g of Intermediate D.

3) Synthesis of NC119(2-(1-(10-(naphthalen-2-yl)anthracene-9-yl)naphthalen-4-yl)-1,10-phenanthroline)

Intermediate C (5g, 0.013mol), 9-(naphthalen-2-yl)anthracene-10-boronic acid (9-(naphthalen-2-yl)anthracene-10-boronic acid) (5.4g, 0.016) in a round-bottom flask mol), tetrakis(triphenylphosphine)palladium(0) (0.6g, 0.5mmol), toluene 100ml, ethanol 10ml, 2M potassium carbonate 8ml, and stirred under reflux for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 4.2 g of NC119 compound.

4) Synthesis of NC124(2-(3-(10-phenylanthracene-9-yl)phenyl)-1,10-phenanthroline)

Intermediate 2 (5 g, 0.015 mol), 9-phenylanthracene-10-boronic acid (5.3 g, 0.018 mol), tetrakis (triphenylphosphine) palladium ( 0) (0.7 g, 0.6 mmol), 100 ml of toluene, 10 ml of ethanol, and 8 ml of 2M potassium carbonate were added and stirred under reflux for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 3.6 g of NC124 compound.

5) Synthesis of NC126 (2-(1-(10-(4-(trimethylsilyl)phenyl)anthracene-9-yl)naphthalen-4-yl)-1,10-phenanthroline)

Intermediate C (5g, 0.013mol), 9-(4-(trimethylsilyl)phenyl)anthracene-10-yl-10-boronic acid (9-(4-(trimethylsilyl)phenyl)anthracene-10-yl in a round-bottom flask -10-boronic acid) (5.8 g, 0.016 mol), tetrakis (triphenylphosphine) palladium (0) (0.6 g, 0.5 mmol), toluene 100 ml, ethanol 10 ml, 2M potassium carbonate 8 ml, and reflux for 12 hours stirred. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 3.7 g of NC126 compound.

6) Synthesis of NC132(2-(1-(10-(4-(pyrimidin-2-yl)phenyl)anthracene-9-yl)naphthalen-4-yl)-1,10-phenanthroline)

Intermediate C (5g, 0.013mol), 9-(4-(pyrimidin-2-yl)phenyl)anthracene-10-yl-10-boronic acid (9-(4-(pyrimidin-2-yl) )phenyl)anthracene-10-yl-10-boronic acid (5.9g, 0.016mol), tetrakis(triphenylphosphine)palladium(0) (0.6g, 0.5mmol), toluene 100ml, ethanol 10ml, 2M potassium carbonate 8ml was added and stirred under reflux for 12 hours.After completion of the reaction, the reaction solution was filtered to obtain a crude product.The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized, and 3g of NC132 compound was obtained.

7) Synthesis of NC175(2-(1-(10-(dibenzofuran-2-yl)anthracene-9-yl)naphthalen-4-yl)-1,10-phenanthroline)

Intermediate C (5g, 0.013mol), 9-(dibenzofuran-2-yl)anthracene-10-boronic acid (9-(dibenzofuran-2-yl)anthracene-10-boronic acid) (6g, 0.016 mol), tetrakis (triphenylphosphine) palladium (0) (0.6 g, 0.5 mmol), toluene 100 ml, ethanol 10 ml, 2M potassium carbonate 8 ml, and reflux stirring for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 4 g of NC175 compound.

8) Synthesis of Intermediate E (9-(4-bromodibenzothiophene-6-yl)-10-phenylanthracene)

In a round-bottom flask, 4,6-dibromodibenzothiophene (10 g, 0.029 mol), 9-phenylanthracene-10-boronic acid (8.7 g, 0.029 mol), tetrakis (triphenylphosphine) palladium (0) (1.4 g, 1.2 mmol), 250 ml of toluene, 30 ml of ethanol, and 15 ml of 2M potassium carbonate were added and stirred at 60° C. for 24 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 8.2 g of Intermediate E.

9) Synthesis of intermediate F(4,4,5,5-tetramethyl-2-(6-(10-phenylanthracene-9-yl)-(dibenzothiophene-4-yl))-1,3,2-dioxaborolane)

Intermediate E (8g, 0.016mol), Bis(pinacolato)diboron) (5.9g, 0.023mol), 1,1-bis(diphenylphosphino)ferrocene dichloropalladium in a round bottom flask (II)(1,1-Bis(diphenylphosphino)ferrocene dichloropalladium(II)) (0.5g, 0.6mmol), 1,4-Dioxane 150ml, Potassium acetate (6.1g) , 0.062 mol) and stirred under reflux for 24 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 7.8 g of Intermediate F.

10) Synthesis of NC151 (2-(4-(10-phenylanthracene-9-yl)dibenzothiophene-6-yl)-1,10-phenanthroline)

In a round bottom flask, 2-bromo-1,10-phenanthroline (3 g, 0.012 mol), Intermediate F (7.8 g, 0.014 mol), tetrakis (triphenylphos Pin) palladium (0) (0.5 g, 0.5 mmol), toluene 200 ml, ethanol 10 ml, tetrahydrofuran (THF) 50 ml, 2M potassium carbonate 8 ml were added and stirred under reflux for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 3.3 g of NC151 compound.

11) Synthesis of NC195 (2-(10-(fluoranthen-3-yl)anthracene-9-yl)-1,10-phenanthroline)

In a round-bottom flask, 2-bromo-1,10-phenanthroline (5 g, 0.019 mol), 9-(fluoroanthen-3-yl) anthracene-10-yl- 10-boronic acid (9-(fluoranthen-3-yl)anthracene-10-yl-10-boronic acid) (9.8g, 0.023mol), tetrakis(triphenylphosphine)palladium(0) (0.9g, 0.8 mmol), toluene 100ml, ethanol 10ml, 2M potassium carbonate 10ml, and stirred under reflux for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 7.2 g of NC195 compound.

12) Synthesis of NC197 (2-(1-(1-phenylpyren-6-yl)naphthalen-4-yl)-1,10-phenanthroline)

In a round-bottom flask, Intermediate C (5 g, 0.013 mol), 6-phenylpyren-1-yl-1-boronic acid (5 g, 0.016 mol), tetrakis ( Triphenylphosphine) palladium (0) (0.6 g, 0.5 mmol), 100 ml of toluene, 10 ml of ethanol, and 8 ml of 2M potassium carbonate were added and stirred under reflux for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 4.1 g of compound NC197.

13) Synthesis of intermediate G (8-amino-5-phenylquinoline-7-carbaldehyde)

In a round-bottom flask, 8-amino-5-bromoquinoline-7-carbaldehyde (15 g, 0.06 mol), phenylboronic acid (7.3 g, 0.06 mol), tetrakis (triphenylphosphine) palladium (0) (2.8 g, 2 mmol), 300 ml of toluene, 30 ml of ethanol, and 30 ml of 2M potassium carbonate were added and stirred under reflux for 12 hours. After the reaction was completed, the reaction solution was filtered through silica gel, and then the silica gel was washed with dichloromethane. After the filtrate was concentrated under reduced pressure, the resulting material was dissolved in dichloromethane, Hx was added to precipitate a powder, and washed to obtain 12 g of Intermediate G.

14) Synthesis of NC209 (6-phenyl-2-(4-(pyren-8-yl)phenyl)-1,10-phenanthroline)

Intermediate G (5 g, 0.028 mol), 1- (4- (pyren-3-yl) phenyl) ethanone (1- (4- (pyren-3-yl) phenyl) ethanone) (6.4 g, 0.028 mol), ABS ethanol 600ml, KOH 8g was added, the temperature was raised to reflux and stirred for 15 hours. After cooling the reaction solution to room temperature, it is filtered. The filtrate was washed with water and then with dichloromethane to obtain 6.5 g of compound NC209.

15) Synthesis of NC223 (2-(1-(phenanthren-9-yl)naphthalen-4-yl)-1,10-phenanthroline)

Intermediate C (5 g, 0.013 mol), phenanthrene-9-boronic acid (3.5 g, 0.016 mol), tetrakis (triphenylphosphine) palladium (0) (0.6) in a round-bottom flask g, 0.5mmol), toluene 100ml, ethanol 10ml, 2M potassium carbonate 8ml, and stirred under reflux for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 4.8 g of NC223 compound.

16) Synthesis of NC231(2-(1-(fluoranthen-3-yl)naphthalen-4-yl)-1,10-phenanthroline)

Intermediate C (5 g, 0.013 mol), fluoranthene-3-boronic acid (3.8 g, 0.016 mol), tetrakis (triphenylphosphine) palladium (0) (0.6) in a round-bottom flask g, 0.5mmol), toluene 100ml, ethanol 10ml, 2M potassium carbonate 8ml, and stirred under reflux for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 4.5 g of NC231 compound.

17) Synthesis of NC232(2-(1-(3-(fluoranthen-3-yl)phenyl)naphthalen-4-yl)-1,10-phenanthroline)

Intermediate C (5g, 0.013mol), 3-(fluoranthen-3-yl)phenylboronic acid) (5g, 0.016mol), tetrakis ( Triphenylphosphine) palladium (0) (0.6 g, 0.5 mmol), 100 ml of toluene, 10 ml of ethanol, and 8 ml of 2M potassium carbonate were added and stirred under reflux for 12 hours. After completion of the reaction, the reaction solution is filtered to obtain a crude product. The filtered crude was dissolved by heating in chloroform, filtered under reduced pressure on silica gel, concentrated and recrystallized to obtain 5.1 g of NC232 compound.

Hereinafter, an example in which an organic electroluminescent device was fabricated using the compound prepared according to the above-described synthesis example as an N-type charge generating layer is disclosed. The thickness or formation conditions of the following organic layers do not limit the scope of the present invention.

Example 7

In the same configuration as in Comparative Example of Experiment 1, the N-type charge generation layer was formed of compound NC119.

Example 8

In the same configuration as in Comparative Example of Experiment 1, the N-type charge generation layer was formed of compound NC124.

Example 9

In the same configuration as in Comparative Example of Experiment 1, the N-type charge generation layer was formed of compound NC126.

Example 10

In the same configuration as in Comparative Example of Experiment 1, the N-type charge generation layer was formed of compound NC132.

Example 11

In the same configuration as in Comparative Example of Experiment 1, the N-type charge generation layer was formed of compound NC151.

Example 12

In the same configuration as in Comparative Example of Experiment 1, the N-type charge generation layer was formed of compound NC175.

Example 13

In the same configuration as in Comparative Example of Experiment 1, the N-type charge generation layer was formed of compound NC195.

Example 14

In the same configuration as in Comparative Example of Experiment 1, the N-type charge generation layer was formed of compound NC197.

Example 15

In the same configuration as in Comparative Example of Experiment 1, the N-type charge generation layer was formed of compound NC223.

Example 16

In the same configuration as in Comparative Example of Experiment 1, the N-type charge generation layer was formed of compound NC231.

Example 17

In the same configuration as in Comparative Example of Experiment 1, the N-type charge generation layer was formed of compound NC232.

The driving voltage, current efficiency, quantum efficiency, and lifetime of the organic light emitting diodes manufactured according to Comparative Examples and Examples 7 to 17 were measured and shown in Table 4 below. In Table 4 below, the result value of the comparative example is 100%, and the result value of the remaining examples is shown as a ratio. In addition, as for the lifetime T95, the time to reach the luminance of 95% compared to the initial luminance of 100% is shown in comparison with the comparative example.

In addition, the current density according to the driving voltage of the organic light emitting diodes manufactured according to Comparative Examples and Examples 7 to 10 was measured and shown in FIG. 16, and the quantum efficiency according to the luminance was measured and shown in FIG. The rate of decrease in luminance was measured and shown in FIG. 18 . In addition, the current density according to the driving voltage of the organic light emitting diodes manufactured according to Comparative Examples and Examples 11 to 14 was measured and shown in FIG. 19, and the quantum efficiency according to the luminance was measured and shown in FIG. The rate of decrease in luminance was measured and shown in FIG. 21 . In addition, the current density according to the driving voltage of the organic light emitting diodes manufactured according to Comparative Examples and Examples 15 to 17 was measured and shown in FIG. 22, and the quantum efficiency according to the luminance was measured and shown in FIG. The rate of decrease in luminance was measured and shown in FIG. 24 .

Driving voltage (%) Current efficiency (%) Quantum efficiency (%) life span(%) comparative example 100.0 100.0 100.0 100.0 Example 7 94.4 96.1 95.9 105.0 Example 8 92.7 99.0 99.5 114.0 Example 9 91.4 98.6 99.4 68.6 Example 10 94.3 101.3 100.4 209.0 Example 11 100.0 93.5 93.2 110.6 Example 12 91.9 99.3 99.7 116.1 Example 13 95.9 99.9 99.3 78.8 Example 14 98.5 95.4 95.6 91.2 Example 15 85.8 100.6 99.5 134.9 Example 16 97.0 96.5 96.1 96.5 Example 17 99.1 96.9 96.6 79.7

16 to 24 and Table 4, compared to the comparative example in which BPhen was used for the N-type charge generation layer in the stack structure, Example 7 in which the compound NC119 was used for the N-type charge generation layer had higher current efficiency and quantum efficiency. Although it decreased by 3.9% and 4.1%, respectively, the driving voltage decreased by 5.6% and the service life increased by 5%. In addition, compared to Comparative Example, Example 8 using compound NC124 for the N-type charge generation layer decreased current efficiency and quantum efficiency by 1% and 0.5%, respectively, but decreased driving voltage by 7.3% and increased lifespan by 5%. In addition, compared to the comparative example, Example 9 using the compound NC126 for the N-type charge generation layer decreased current efficiency, quantum efficiency, and lifetime by 1.4%, 0.6%, and 31.4%, respectively, but the driving voltage decreased by 8.6%. In addition, compared to the comparative example, Example 10 using the compound NC132 for the N-type charge generation layer decreased the driving voltage by 5.7%, and the current efficiency, quantum efficiency and lifetime were 1.3% and 0.4%, respectively. 109% increase. In addition, compared to the comparative example, Example 11 in which the compound NC151 was used for the N-type charge generation layer decreased current efficiency and quantum efficiency by 6.5% and 6.8%, respectively, but the driving voltage was unchanged and the lifespan was increased by 10.6%. In addition, compared to Comparative Example, Example 12, in which the compound NC175 was used for the N-type charge generation layer, decreased current efficiency and quantum efficiency by 0.7% and 0.3%, respectively, but decreased the driving voltage by 8.1% and the lifetime increased by 16.1%. In addition, compared to the comparative example, Example 13 using the compound NC195 for the N-type charge generation layer decreased current efficiency, quantum efficiency, and lifetime by 0.1%, 0.7%, and 21.2%, respectively, but the driving voltage was decreased by 4.1%. In addition, compared to the comparative example, Example 14 using the compound NC197 for the N-type charge generation layer decreased current efficiency, quantum efficiency, and lifetime by 4.6%, 4.4%, and 8.8%, respectively, but the driving voltage was decreased by 1.5%. In addition, compared to the comparative example, Example 15 using the compound NC223 for the N-type charge generation layer decreased the quantum efficiency by 0.5%, but decreased the driving voltage by 14.2%, and increased the current efficiency and the lifespan by 0.6% and 34.9%, respectively. In addition, compared to the comparative example, Example 16 using the compound NC231 for the N-type charge generation layer decreased current efficiency, quantum efficiency, and lifetime by 3.5%, 3.9%, and 3.5%, respectively, but the driving voltage was decreased by 3%. In addition, compared to the comparative example, Example 17, in which the compound NC232 was used for the N-type charge generation layer, decreased current efficiency, quantum efficiency, and lifetime by 3.1%, 3.4%, and 20.3%, respectively, but the driving voltage was decreased by 0.9%.

From the above results, it can be seen that by configuring the N-type charge generation layer including the compound of the present invention, the driving voltage of the device is reduced and the lifespan is generally increased.

In addition, an embodiment in which an organic electroluminescent device is manufactured using the compound prepared according to the above-described synthesis example as an electron transport layer is disclosed.

Example 18

In the same configuration as in Comparative Example of Experiment 1, the second electron transport layer was formed of compound NC119.

Example 19

In the same configuration as in Comparative Example of Experiment 1, the second electron transport layer was formed of compound NC124.

Example 20

In the same configuration as in Comparative Example of Experiment 1, the second electron transport layer was formed of compound NC197.

Example 21

In the same configuration as in Comparative Example of Experiment 1, the second electron transport layer was formed of compound NC209.

The driving voltage, current efficiency, quantum efficiency, and lifetime of the organic light emitting diodes manufactured according to Comparative Examples and Examples 18 to 21 were measured and shown in Table 5 below. In addition, the current density according to the driving voltage of the organic light emitting diodes manufactured according to Comparative Examples, Examples 18 and 19 is shown in FIG. The spectrum is shown in FIG. 26, and the rate of decrease in luminance according to time of the organic light emitting diodes manufactured according to Comparative Examples, Examples 18 and 19 is shown in FIG. 27 . In addition, the current density according to the driving voltage of the organic electroluminescent devices manufactured according to Comparative Examples, Examples 20 and 21 is shown in FIG. 28, and the light emission of the organic electroluminescent devices manufactured according to Comparative Examples, Examples 20 and 21 The spectrum is shown in FIG. 29, and the rate of decrease in luminance with time of the organic light emitting diodes manufactured according to Comparative Examples, Examples 20 and 21 is shown in FIG.

Driving voltage (%) Current efficiency (%) Quantum efficiency (%) life span(%) comparative example 100.0 100.0 100.0 100.0 Example 18 91.9 99.3 99.7 114.0 Example 19 94.5 97.2 97.2 91.2 Example 20 95.6 98.4 98.5 110.6 Example 21 90.0 94.1 94.0 79.7

Referring to Table 5 and FIGS. 25 to 28, in Example 18 in which the compound NC119 was used for the electron transport layer, compared to the comparative example _{in which Alq 3 was used for the electron transport layer in the stack structure, the current efficiency and the quantum efficiency were 0.7% and 0.3, respectively.} % decreased, but the driving voltage decreased by 8.1% and the service life increased by 14%. In addition, compared to the comparative example, Example 19 using the compound NC124 for the electron transport layer decreased current efficiency, quantum efficiency, and lifetime by 2.8%, 2.8%, and 8.8%, respectively, but the driving voltage was decreased by 5.5%. In addition, compared to the comparative example, Example 20 using the compound NC197 for the electron transport layer decreased the current efficiency and quantum efficiency by 1.6% and 1.5%, respectively, but the driving voltage decreased by 4.4% and the lifespan was increased by 10.6%. In addition, in Example 21 in which the compound NC209 was used for the electron transport layer, the current efficiency, quantum efficiency, and lifetime were decreased by 5.9%, 6%, and 20.3%, respectively, but the driving voltage was decreased by 10%.

From the above results, it can be seen that by configuring the electron transport layer including the compound of the present invention, the driving voltage of the device is reduced and the lifespan is increased.

As described above, the compound containing a nitrogen atom of the present invention is rich in electrons by including two nitrogen atoms, and thus has a fast electron mobility to facilitate electron transport. Accordingly, in the organic light emitting device of the present invention, by using a compound in at least one of the electron transport layers included in the light emitting part, the electrons transferred from the N-type charge generating layer are efficiently transferred to the light emitting layer.

In addition, the compound containing a nitrogen atom of the present invention contains ^{nitrogen (N) of sp 2} hybrid orbital, which is relatively rich in electrons, and this nitrogen is bound to an alkali metal or alkaline earth metal as a dopant in the N-type charge generating layer. ) to form a gap state. By the formed gap state, it is possible to smoothly transfer electrons from the N-type charge generation layer to the electron transport layer. Accordingly, in the organic electroluminescent device of the present invention, by using the compound of the present invention in the N-type charge generating layer, electrons can be smoothly transferred from the N-type charge generating layer to the electron transporting layer. In addition, since the compound containing the nitrogen atom is combined with the alkali metal or alkaline earth metal included in the N-type charge generating layer, the alkali metal or alkaline earth metal does not diffuse into the P-type charge generating layer, and thus the lifespan may be improved.

Accordingly, the organic electroluminescent device of the present invention uses a compound containing a nitrogen atom in at least one of the electron transporting layers and the N-type charge generating layers included in the light emitting part, so that electrons transferred from the N-type charge generating layer are transferred to the light emitting layer. It is possible to improve device efficiency and device performance by efficiently transferring it to In addition, since electrons are smoothly transferred from the N-type charge generating layer to the electron transport layer, the problem of a decrease in lifespan caused by poor electron injection can be improved. Further, it is possible to improve a problem in that a driving voltage generated when electrons injected into the N-type charge generation layer moves to the electron transport layer due to a difference in LUMO energy level between the electron transport layer and the N-type charge generation layer is increased.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the technical configuration of the present invention can be changed to other specific forms by those skilled in the art to which the present invention pertains without changing the technical spirit or essential features of the present invention. It will be appreciated that this may be practiced. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. In addition, the scope of the present invention is indicated by the claims to be described later rather than the above detailed description. In addition, all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention.

100: organic electroluminescent device 110: anode
120: hole injection layer 130: first hole transport layer
140: first light emitting layer 150: first electron transport layer
160: charge generation layer 160N: N-type charge generation layer
160P: P-type charge generation layer 170: second hole transport layer
190: second light emitting layer 200: second electron transport layer
210: electron injection layer 220: cathode

Claims (17)

at least two or more light emitting units including a light emitting layer and an electron transport layer; and
and a charge generation layer positioned between the light emitting parts,
At least one of the charge generation layer and the electron transport layer is one of the following compounds, or an organic electroluminescent device, characterized in that composed of a compound represented by the following formula (1).

[Formula 1]

In Formula 1, Ar ₁ , Ar ₂ , Ar ₃ , L ₁ , L ₂ , and L ₃ are as shown in the table below.

According to claim 1,
Among the at least two or more light emitting units, one of the light emitting units is a light emitting unit that emits blue light and the other is a light emitting unit that emits yellow-green light.
3. The method of claim 2,
The electron transport layer is an organic electroluminescent device, characterized in that included in the light emitting portion for emitting the yellow-green.
delete delete delete delete delete delete delete delete at least two or more light emitting units including a light emitting layer and an electron transport layer; and
and a charge generation layer between the light emitting parts,
At least one of the charge generation layer and the electron transport layer is an organic electroluminescent device, characterized in that composed of a compound represented by the following formula (1).
[Formula 1]

In Formula 1,
Ar ₁ is phenanthrolinylene,
L ₁ is a single bond, a substituted or unsubstituted C6 to C60 aryl group, a substituted or unsubstituted C3 to C60 heteroaryl group, and a C1 to C20 alkyl group,
L ₂ is a single bond, one of substituted or unsubstituted anthracenylene and substituted or unsubstituted pyrenylene,
L3-Ar2 and Ar3 impart an electron or hole property to the compound, and when imparting the hole property, it is one of the compounds represented by Formula 4 one
[Formula 4]

and Ar is aryl.
[Formula 5]

13. The method of claim 12,
The L1 serves as a pathway for the abundant electrons of L2 to reach Ar1 through conjugation control, and the L2 is an organic electroluminescent device, characterized in that it improves the pi-electron density through the introduction of an aromatic macrocycle.
13. The method of claim 12,
L1 is a single bond, substituted or unsubstituted phenylene, alkylphenylene, halophenylene, cyanophenylene, naphthylene, alkylnaphthylene, biphenylene, alkylbiphenylene, pyridylene, pyrimidylene, Quinolinylene, isoquinolinylene, quinoxalinylene, pyrazinylene, quinazolinylene, naphthyridinylene, thiophenylene, furanylene, benzothiophenylene, benzofuranylene, dibenzothiophenylene, dibenzofura An organic electroluminescent device, characterized in that one of nylene, fluorenylene, carbazolylene, imidazolylene, triphenylenylene, fluoroanthenylene and diakafluorenylene.
delete delete 13. The method of claim 12,
The phenanthrolinylene of Formula 1 is an organic electroluminescent device, characterized in that it binds to the metal included in the charge generating layer.

Images