ORGANIC LIGHT EMITTING ELEMENT AND DISPLAY DEVICE

Embodiments of the disclosure relate to an organic light emitting element and a display device. Specifically, there may be provided an organic light emitting element including a first compound represented by chemical formula 1 and a second compound represented by chemical formula 2 to provide excellent efficiency, long lifespan or low driving voltage and a display device including the organic light emitting element.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean Patent Application No. 10-2022-0191364 filed on Dec. 31, 2022 in the Korean Intellectual Property Office, the disclosure of which is hereby incorporated by reference in its entirety.

BACKGROUND

Technical Field

Embodiments of the disclosure relate to an organic light emitting element and a display device.

Description of the Related Art

In general, organic light emission refers to a phenomenon in which electric energy is converted into light energy by an organic material. The organic light emitting element refers to a light emitting element using the organic light emission phenomenon. The organic light emitting element has a structure including an anode, a cathode, and an organic material layer disposed therebetween.

The organic material layer may have a multilayer structure composed of different materials to increase the efficiency and stability of the organic light emitting element and may include a light emitting layer (also referred to as an emission material layer (EML)).

The lifespan and efficiency are the most important issues with organic light emitting elements. The efficiency, lifespan, and driving voltage are related to each other. If the efficiency is increased, the driving voltage is relatively decreased, so that the crystallization of the organic material by the Joule heating during driving is reduced, leading to an increase in lifespan.

The role of the light emitting layer EML is important to enhance the light emitting properties of the organic light emitting element and increase the lifespan. In particular, to have high-efficiency characteristics, the host material of the light emitting layer is required to have a high triplet energy level, and further a sufficient stability of the material is needed.

BRIEF SUMMARY

An organic light emitting element may include an organic material layer including a hole injection layer and a charge generation layer between an anode and a cathode. The hole injection layer and the charge generation layer are layers closely related to hole injection and movement characteristics that determine the characteristics of the device, and organic electron acceptor compounds may be used for efficient hole generation, injection and movement. Since the organic electron acceptor compound includes a strong electron withdrawing group (EWG), when the hole injection layer is doped with it, it may withdraw electrons from a high occupied molecular orbital (HOMO) energy level of the adjacent hole transport layer to a low occupied molecular orbital (LUMO) energy level of the organic electron acceptor compound to generate holes and inject the holes into the hole transport layer. Therefore, organic electron acceptor compounds may be designed to include a number of strong electron withdrawing groups for efficient hole generation, injection and transfer.

Organic electron acceptor compounds may contain strong electron withdrawing groups to have low LUMO energy levels. However, since the organic electron acceptor compounds typically have a low miscibility with the hole transporting compound, a high driving voltage and low luminous efficiency may occur due to inefficient charge injection and transfer characteristics. Accordingly, the present disclosure relates to an organic light emitting element and a display device that may have high efficiency, long lifespan and/or low driving voltage.

Accordingly, an object of the disclosure may be to provide an organic light emitting element and a display device that may have high efficiency, long lifespan, and/or low driving voltage.

Objects of the present disclosure are not limited to the above-mentioned object. Other objects and advantages of the present disclosure that are not mentioned may be understood based on following descriptions, and may be more clearly understood based on aspects of the present disclosure. Further, it may be easily understood that the objects and advantages of the present disclosure may be realized using means shown in the claims and combinations thereof.

To achieve these and other advantages and in accordance with objects of the disclosure, as embodied and broadly described herein, an organic light emitting element includes a first electrode, a second electrode, and an organic material layer positioned between the first electrode and the second electrode.

The organic material layer may include a first compound represented by chemical formula 1 described below.

The organic material layer may include a second compound represented by chemical formula 2 described above.

Embodiments of the disclosure may provide a display device including the organic light emitting element described above.

According to embodiments of the disclosure, there may be provided an organic light emitting element having high emission efficiency, long lifespan, and/or low driving voltage.

According to embodiments of the disclosure, there may be provided an organic light emitting element having high emission efficiency, long lifespan and/or low driving voltage by including a layer having excellent hole injection characteristics or electron injection characteristics.

Effects of the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned may be clearly understood by those skilled in the art from following descriptions.

It is to be understood that both the foregoing general description and the following detailed description of the present disclosure are merely by way of example and are intended to provide further explanation of the inventive concepts as claimed.

DETAILED DESCRIPTION

Reference will now be made in detail to some of the examples and embodiments of the disclosure illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

In the following description of examples or embodiments of the disclosure, reference will be made to the accompanying drawings in which, by way of illustration, specific examples or embodiments are shown that can be implemented by a person skilled in the art, and in which the same reference numerals and signs can be used to designate the same or like components even when they are shown in different of the accompanying drawings. Further, in the following description of examples or embodiments of the disclosure, detailed descriptions of well-known functions and components incorporated herein will be omitted when it is determined that the description of the same may render subject matter described in conjunction with the embodiments of the disclosure less clear. The terms such as “including”, “having”, “containing”, “constituting” “make up of”, and “formed of” used herein are generally intended to allow other components to be added unless the terms are used with the term “only”. As used herein, singular forms are intended to include plural forms unless the context clearly indicates otherwise.

Hereinafter, various embodiments of the disclosure are described in detail with reference to the accompanying drawings.

As used herein, the term “halo” or “halogen” includes fluorine (F), chlorine (Cl), bromine (Br), and iodine (I), and the like, unless otherwise specified.

As used herein, the term “alkyl” or “alkyl group” may mean a radical of a saturated aliphatic functional group having 1 to 60 carbon atoms linked by a single bond and including a straight chain alkyl group, branched chain alkyl group, cycloalkyl (alicyclic) group, alkyl-substituted cycloalkyl group, or cycloalkyl-substituted alkyl group, unless otherwise specified.

As used herein, the term “haloalkyl group” or “halogenalkyl group” may mean a halogen-substituted alkyl group unless otherwise specified.

As used herein, the term “alkenyl” or “alkynyl” may have a double bond or a triple bond, respectively, and may include a straight or branched chain group and may have 2 to 60 carbon atoms unless otherwise specified.

As used herein, the term “cycloalkyl” may refer to an alkyl forming a ring having 3 to 60 carbon atoms, unless otherwise specified.

As used herein, the term “alkoxy group” or “alkyloxy group” refers to an alkyl group to which an oxygen radical is bonded, and may have 1 to 60 carbon atoms unless otherwise specified.

As used herein, the term “alkenoxyl group”, “alkenoxy group”, “alkenyloxyl group”, or “alkenyloxy group” refers to an alkenyl group to which an oxygen radical is attached, and may have 2 to 60 carbon atoms unless otherwise specified.

As used herein, the terms “aryl group” and “arylene group” each refer to a group that may have 6 to 60 carbon atoms unless otherwise specified, but are not limited thereto. In the disclosure, the aryl group or the arylene group may include a monocyclic type, a ring assembly, a fused polycyclic system, a spiro compound, and the like. For example, the aryl group includes, but is not limited to, phenyl, biphenyl, naphthyl, anthryl, indenyl, phenanthryl, triphenylenyl, pyrenyl, peryleneyl, chrysenyl, naphthacenyl, or fluoranthenyl. The term “naphthyl” may relate to 1-naphthyl and 2-naphthyl, and the term “anthryl” may relate to 1-anthryl, 2-anthryl and 9-anthryl.

In the disclosure, the term “fluorenyl group” or “fluorenylene group” may refer to a monovalent or divalent functional group, respectively, of fluorene, unless otherwise specified. The “fluorenyl group” or “fluorenylene group” may mean a substituted fluorenyl group or a substituted fluorenylene group. “Substituted fluorenyl group” or “substituted fluorenylene group” may refer to a monovalent or divalent functional group of substituted fluorene. “Substituted fluorene” may mean that at least one of the following substituents R, R′, R″ and R′″ is a functional group other than hydrogen. It may include a situation where R and R′ are bonded to each other to form a spiro compound together with the carbon to which they are bonded.

As used herein, the term “spiro compound” refers to a compound that has a ‘spiro union’, and the term “spiro union” means a union formed from two rings that share only one atom. In this case, the atom shared by the two rings may be referred to as a ‘spiro atom’.

As used herein, the term “heterocyclic group” may include not only an aromatic ring, such as a “heteroaryl group” or “heteroarylene group” but also a non-aromatic ring and, unless otherwise specified, means a ring with 2 to 50 carbon atoms and one or more heteroatoms, but is not limited thereto. As used herein, the term “heteroatom” refers to N, O, S, P or Si unless otherwise specified, and the term “heterocyclic group” may designate a monocyclic group containing a heteroatom, a ring assembly, a fused polycyclic system, or a spiro compound.

The “heterocyclic group” may include a ring containing SO2instead of carbon forming the ring. For example, the “heterocyclic group” may include the following compounds.

As used herein, the term “ring” may include monocycles and polycycles, may include hydrocarbon rings as well as heterocycles containing at least one heteroatom, or may include aromatic and non-aromatic rings.

As used herein, the term “polycycle” may include ring assemblies, fused polycyclic systems, and/or spiro compounds, may include aromatic as well as non-aromatic compounds, and/or may include heterocycles containing at least one heteroatom as well as hydrocarbon rings.

As used herein, the term “aliphatic ring group” refers to a cyclic hydrocarbon other than the aromatic hydrocarbon, may include a monocyclic type, a ring assembly, a fused polycyclic system, and a spiro compound and, unless otherwise specified, may designate a ring having 3 to 60 carbon atoms. For example, a fusion of benzene, which is an aromatic ring, and cyclohexane, which is a non-aromatic ring, also corresponds to an aliphatic ring.

As used herein, the term “alkylsilyl group” may refer to a monovalent substituent in which three alkyl groups are bonded to a Si atom.

As used herein, the term “arylsilyl group” may refer to a monovalent substituent in which three aryl groups are bonded to a Si atom.

As used herein, the term “alkylarylsilyl group” may refer to a monovalent substituent in which one alkyl group and two aryl groups are bonded to a Si atom or two alkyl groups and one aryl group are bonded to the Si atom.

As used herein, the term “ring assembly” means that two or more ring systems (single or fused ring systems) are directly connected to each other through single or double bonds. For example, in the case of an aryl group, a biphenyl group or a terphenyl group may be a ring assembly but is not limited thereto.

As used herein, the term “fused polycyclic system” refers to a type of fused rings sharing at least two atoms. For example, in the case of an aryl group, a naphthalenyl group, a phenanthrenyl group, or a fluorenyl group may be a fused polycyclic system, but is not limited thereto.

When prefixes are named successively, it may mean that the substituents are listed in the order specified first. For example, an arylalkoxy group may mean an alkoxy group substituted with an aryl group, an alkoxycarbonyl group may mean a carbonyl group substituted with an alkoxy group, and an arylcarbonylalkenyl group may mean an alkenyl group substituted with an arylcarbonyl group. The arylcarbonyl group may be a carbonyl group substituted with an aryl group.

Unless otherwise explicitly stated, in the term “substituted” or “unsubstituted” as used herein, “substituted” may mean being substituted with one or more substituents selected from the group consisting of halogen, an amino group, a nitrile group, nitro group, a C1-C20 alkyl group, a C1-C20 alkoxy group, a C1-C20 alkylamine group, a C1-C20 alkylthiophene group, a C6-C20 arylthiophene group, a C2-C20 alkenyl group, a C2-C20 alkynyl group, a C3-C20 cycloalkyl group, a C6-C20 aryl group, a C8-C20 arylalkenyl group, a silane group, a boron group, a germanium group, and a C2-C20 heterocyclic group including at least one heteroatom selected from the group consisting of O, N, S, Si and P, but is not limited to these substituents.

In the disclosure, the ‘functional group names’ corresponding to the aryl group, arylene group, and heterocyclic group provided as examples of the symbols and their substituents may be described with ‘the names of the functional groups reflecting the valence’, but may also be described with ‘the names of the parent compounds.’ For example, in the case of ‘phenanthrene’, which is a type of aryl group, its name may be specified with its group identified, such as ‘phenanthryl (group)’ for the monovalent group, and ‘phenanthrylene (group)’ as the divalent group, but may also be specified as ‘phenanthrene’, which is the name of the parent compound, regardless of the valence. Similarly, pyrimidine may be specified as ‘pyrimidine’ regardless of the valence or may also be specified as pyrimidinyl (group) for the monovalent group and as pyrimidylene (group) for the divalent group. Therefore, in the disclosure, when the type of the substituent is specified with the name of the parent compound, it may mean an n-valent ‘group’ formed by detachment of the hydrogen atom bonded to a carbon atom and/or a heteroatom of the parent compound.

Further, unless explicitly stated, the formulas used in the disclosure may be applied in the same manner as the definition of the substituent by the exponent definition of the following formulas.

When a is 0, it means that the substituent R1does not exist, meaning that hydrogen is bonded to each of the carbon atoms forming the benzene ring. In this case, the chemical formula or chemical compound may be specified without expressing the hydrogen bonded to the carbon. Further, when a is 1, one substituent R1is bonded to any one of the carbon atoms forming the benzene ring, and when a is 2 or 3, it may be bonded as follows. When a is an integer of 4 to 6, it is bonded to the carbon of the benzene ring in a similar manner, and when a is an integer of 2 or more, R1may be identical or different.

In the disclosure, when substituents are bonded to each other to form a ring, it may mean that adjacent groups are bonded to each other to form a monocycle or fused polycycle, and the monocycle or fused polycycle may include heterocycles containing at least one heteroatom as well as hydrocarbon rings and may include aromatic and non-aromatic rings.

In the disclosure, organic light emitting element may mean a component(s) between an anode and a cathode of an electronic device or an organic light emitting diode including an anode, a cathode, and component(s) positioned therebetween.

In some cases, in the disclosure, organic light emitting element may mean an organic light emitting diode and a panel including the same, or an electronic device including the panel and circuitry. The electronic device may include, e.g., a display device, a lighting device, a solar cell, a portable or mobile terminal (e.g., a smart phone, a tablet, a PDA, an electronic dictionary, or PMP), a navigation terminal, a game device, various TVs, and various computer monitors but, without being limited thereto, may include any type of device including the component(s).

FIG.1illustrates a system configuration of a display device100according to embodiments of the disclosure.

Referring toFIG.1, a display device100according to embodiments of the disclosure includes a display panel PNL in which a plurality of data lines DL and a plurality of gate lines GL are disposed, and a plurality of subpixels SP defined by the plurality of data lines DL and the plurality of gate lines GL are arranged, a data driving circuit DDC for driving the plurality of data lines DL, a gate driving circuit GDC for driving the plurality of gate lines GL, and a controller CTR for controlling the data driving circuit DDC and the gate driving circuit GDC.

The controller CTR supplies various control signals DCS and GCS to the data driving circuit DDC and the gate driving circuit GDC to control the data driving circuit DDC and the gate driving circuit GDC.

The data driving circuit DDC receives the image data from the controller CTR and supplies data voltage to the plurality of data lines DL, thereby driving the plurality of data lines DL. Herein, the data driving circuit DDC is also referred to as a ‘source driving circuit’.

The gate driving circuit GDC sequentially drives the plurality of gate lines GL by sequentially supplying scan signals to the plurality of gate lines GL. Here, the gate driving circuit GDC is also referred to as a ‘scan driving circuit’.

The gate driving circuit GDC sequentially supplies scan signals of ‘On voltage’ or ‘Off voltage’ to the plurality of gate lines GL under the control of the controller CTR.

When a specific gate line is opened by the gate driving circuit GDC, the data driving circuit DDC converts the image data received from the controller CTR into an analog data voltage and supplies the analog data voltage to the plurality of data lines DL.

The data driving circuit DDC may be positioned on only one side (e.g., the top or bottom side) of the display panel PNL and, in some cases, the driving circuit may be positioned on each of two opposite sides (e.g., both the top and bottom sides) of the display panel PNL depending on, e.g., driving schemes or panel designs.

The gate driving circuit GDC may be positioned on only one side (e.g., the left or right side) of the display panel PNL and, in some cases, the gate driving circuit GDR may be positioned on each of two opposite sides (e.g., both the left and right sides) of the display panel PNL depending on, e.g., driving schemes or panel designs.

The display device100according to embodiments of the disclosure may be an organic light emitting display device, a liquid crystal display device, a plasma display device, and the like.

When the display device100according to the embodiments of the disclosure is an organic light emitting display device, each subpixel SP arranged on the display panel PNL may be composed of a circuit element such as an organic light emitting diode (OLED) that is a self-luminous element, and a driving transistor for driving the OLED.

The type and number of circuit elements constituting each subpixel SP may be varied depending on functions to be provided and design schemes.

FIG.2illustrates a subpixel circuit of a display device according to embodiments of the disclosure.

Referring toFIG.2, each subpixel SP may basically include an organic light emitting element200and a driving transistor DRT for driving the organic light emitting element200.

Each subpixel SP may further include a first transistor T1to transfer data voltage VDATA to a first node N1, which corresponds to a gate node of the driving transistor DRT, and a storage capacitor C1to maintain the data voltage VDATA corresponding to an image signal voltage or a voltage corresponding to the data voltage VDATA for the time of one frame.

The organic light emitting element200may include a first electrode210(anode electrode or cathode electrode), an organic material layer230, and a second electrode220(cathode electrode or anode electrode).

As an example, a base voltage EVSS may be applied to the second electrode220of the organic light emitting diode200.

The driving transistor DRT supplies a driving current to the organic light emitting diode200, thereby driving the organic light emitting diode200.

The driving transistor DRT includes the first node N1, second node N2, and third node N3.

The first node N1of the driving transistor DRT is a node corresponding to the gate node and may be electrically connected with the source node or drain node of the first transistor T1.

The second node N2of the driving transistor DRT may be electrically connected with the first electrode210of the organic light emitting diode200, and may be a source node or a drain node.

The third node N3of the driving transistor DRT may be a node to which driving voltage EVDD is applied, may be electrically connected with a driving voltage line DVL for supplying the driving voltage EVDD, and may be the drain node or source node.

The first transistor T1may be electrically connected between the data line DL and the first node N1of the driving transistor DRT, and may be controlled by receiving the scan signal SCAN through the gate line and the gate node.

The storage capacitor C1may be electrically connected between the first node N1and second node N2of the driving transistor DRT.

The storage capacitor C1is an external capacitor intentionally designed to be outside the driving transistor DRT, but not a parasite capacitor (e.g., Cgs or Cgd) which is an internal capacitor present between the first node N1and the second node N2of the driving transistor DRT.

FIG.3is a cross-sectional view schematically illustrating an organic light emitting element according to embodiments of the disclosure.

The organic light emitting element200according to embodiments of the disclosure includes a first electrode210, a second electrode220, and an organic material layer230positioned between the first electrode210and the second electrode220.

For example, the first electrode210may be the anode electrode, and the second electrode220may be the cathode electrode.

For example, the first electrode210may be a transparent electrode, and the second electrode130may be a reflective electrode. In another example, the first electrode210may be a reflective electrode, and the second electrode130may be a transparent electrode.

The organic material layer230is a layer positioned between the first electrode210and the second electrode220and including an organic material and may be composed of a plurality of layers.

The organic material layer230includes a first compound232aand a second compound232b. The first compound232aand the second compound232bare described below in detail. As the organic material layer230includes the above-described first compound232aand second compound232b, the organic light emitting element may have high efficiency, long lifespan, and/or low driving voltage.

In other words, the organic material layer230may include a light emitting layer. The organic layer230may further include at least one of a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer.

For example, the organic material layer230may include a hole injection layer positioned on the first electrode210, a hole transport layer positioned on the hole injection layer, a light emitting layer positioned on the hole transport layer, an electron transport layer positioned on the light emitting layer, and an electron injection layer positioned on the electron transport layer. In such an example, the first electrode210may be the anode electrode, and the second electrode220may be the cathode electrode.

The light emitting layer is a layer in which as holes and electrons transferred from the first electrode210and the second electrode130meet to emit light and may include, e.g., a host material and a dopant.

The organic material layer230may include, e.g., a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. The hole injection layer may be positioned on the first electrode210as the anode electrode. The hole transport layer may be positioned on the hole injection layer. The light emitting layer may be positioned on the hole transport layer. The electron transport layer may be positioned on the light emitting layer. The electron injection layer may be positioned on the electron transport layer.

FIG.4is a cross-sectional view schematically illustrating an organic light emitting element300according to embodiments of the disclosure.

The organic light emitting element300may include a first electrode310, a second electrode320, and an organic material layer330positioned between the first electrode310and the second electrode320.

The organic material layer330may include a first light emitting layer331, a second light emitting layer333, and a first layer332positioned between the first light emitting layer331and the second light emitting layer333. In other words, the organic light emitting element300may be a tandem type organic light emitting element including two or more light emitting layers. The tandem type organic light emitting element may include a plurality of stacks each including a light emitting layer. For example, the tandem type organic light emitting element may include a first stack including a first light emitting layer331and a second stack including a second light emitting layer333. In this example, the first stack may include additional functional layers in addition to the first light emitting layer331. Further, the second stack may include additional functional layers in addition to the second light emitting layer333.

The first light emitting layer331and the second light emitting layer333may be formed of the same material or of different materials. The first light emitting layer331may emit light having a first color, and the second light emitting layer333may emit light having a second color. The first color and the second color may be the same or different from each other.

The first layer332may include a first compound332aand a second compound332b. The first compound332aand the second compound332bare described below in detail. As the organic material layer332includes the first compound332aand second compound332b, the organic light emitting element may have high efficiency, long lifespan, and/or low driving voltage.

The first layer332may be a charge generation layer. For example, the organic light emitting element300may include a charge generation layer positioned between the first light emitting layer331and the second light emitting layer333. The charge generation layer may include a p-type charge generation layer and an n-type charge generation layer.

The first stack may further include a functional layer in addition to the first light emitting layer331. For example, the first stack may include a hole injection layer, a first hole transport layer, a first light emitting layer331and a first electron transport layer.

The second stack may further include a functional layer in addition to the second light emitting layer333. For example, the second stack may include a second hole transport layer, a second light emitting layer333, a second electron transport layer, and an electron injection layer.

The hole injection layer may be positioned on the first electrode310as the anode electrode. The first hole transport layer may be positioned on the hole injection layer. The first light emitting layer331may be positioned on the first hole transport layer. The first electron transport layer may be positioned on the first light emitting layer331. The charge generation layer may be positioned on the first electron transport layer. The second hole transport layer may be positioned on the charge generation layer. The second light emitting layer332may be positioned on the second hole transport layer. The second electron transport layer may be positioned on the second light emitting layer332. The electron injection layer may be positioned on the second electron transport layer. In this example, the first layer333may be a charge generation layer. In this example, the first compound332amay be a p dopant of the charge generation layer, and the second compound332bmay be an n dopant of the charge generation layer.

The hole injection layer may include an amine-based compound. For example, the hole injection layer may include one or more of HATCN (1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile) and NPD (N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the material for the hole injection layer is not limited to those described above, and may include other compounds that may be used as hole injection materials in the field of organic light emitting elements.

The first hole transport layer may include an amine-based compound. For example, the hole transport layer may include one or more of HATCN (1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile) and NPD (N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the material for the first hole transport layer is not limited to those described above, and may include other compounds that may be used as hole transport materials in the field of organic light emitting elements.

The first light emitting layer331may be a fluorescent light emitting layer or a phosphorescent light emitting layer. The fluorescent light emitting layer may include one or more of a boron-based compound, an anthracene-based compound, and a pyrene-based compound. The phosphorescent light emitting layer may include at least one of a carbazole-based compound and an iridium-based compound.

The first electron transport layer may include at least one of an azine-based compound and an imidazole-based compound. For example, the azine-based compound may be TmPyPB (1,3,5-tri(m-pyridin-3-ylphenyl)benzene). The imidazole-based compound may be TPBi (2,2′,2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H benzimidazole)). However, the material for the electron transport layer is not limited to those described above, and may include other compounds that may be used as electron transport materials in the field of organic light emitting elements.

The charge generation layer may include the second compound332bas the n dopant. Further, the charge generation layer may include a phenanthroline-based compound as the n dopant. The phenanthroline-based compound may be bphen (bathophenanthroline). However, the n dopant that may be used in addition to the second compound332bis not limited to those described above. When the first layer332, which is the charge generation layer, includes the second compound332bas the n dopant, the organic light emitting element300may have high efficiency, long lifespan, or low driving voltage.

The charge generation layer may include the first compound332aas the p dopant. Further, the charge generation layer may further include an amine-based compound as the p dopant. The amine-based compound may be NPD (N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the p dopant that may be used in addition to the first compound332ais not limited to those described above. When the first layer332, which is the charge generation layer, includes the first compound332aas the p dopant, the organic light emitting element300may have high efficiency, long lifespan, or low driving voltage.

The second hole transport layer may include an amine-based compound. For example, the hole transport layer may include one or more of HATCN (1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile) and NPD (N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the material for the second hole transport layer is not limited to those described above, and may include other compounds that may be used as hole transport materials in the field of organic light emitting elements.

The second light emitting layer333may be a fluorescent light emitting layer or a phosphorescent light emitting layer. The fluorescent light emitting layer may include one or more of a boron-based compound, an anthracene-based compound, and a pyrene-based compound. The phosphorescent light emitting layer may include at least one of a carbazole-based compound and an iridium-based compound. The carbazole-based compound may be CBP (4,4′-bis(N-carbazolyl)-1,1′-biphenyl). The iridium-based compound may be Ir(ppy)3(tris(2-phenylpyridine) iridium(III)). However, the material for the light emitting layer is not limited to those described above, and may include other compounds that may be used as light emitting layer materials in the field of organic light emitting elements.

The second electron transport layer may include at least one of an azine-based compound and an imidazole-based compound. For example, the azine-based compound may be TmPyPB (1,3,5-tri(m-pyridin-3-ylphenyl)benzene). The imidazole-based compound may be TPBi (2,2′,2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H benzimidazole)). However, the material for the electron transport layer is not limited to those described above, and may include other compounds that may be used as electron transport materials in the field of organic light emitting elements.

The electron injection layer may include at least one of an azine-based compound and an imidazole-based compound. For example, the electron injection layer may include one or more of LIF and LiQ. However, the material for the electron injection layer is not limited to those described above, and may include other compounds that may be used as electron injection materials in the field of organic light emitting elements.

FIG.5is a cross-sectional view schematically illustrating an organic light emitting element400according to embodiments of the disclosure.

The organic light emitting element400may include a first electrode410, a second electrode420, and an organic material layer430positioned between the first electrode410and the second electrode420.

The organic material layer430may include a first light emitting layer431, a second light emitting layer433, and a first layer432positioned between the first light emitting layer431and the second light emitting layer433. In other words, the organic light emitting element400may be a tandem type organic light emitting element including two or more light emitting layers. The tandem type organic light emitting element may include a plurality of stacks each including a light emitting layer. For example, the tandem type organic light emitting element may include a first stack including a first light emitting layer431and a second stack including a second light emitting layer433. In this example, the first stack may include additional functional layers in addition to the first light emitting layer431. Further, the second stack may include additional functional layers in addition to the second light emitting layer433.

The first light emitting layer431and the second light emitting layer433may be formed of the same material or different materials. The first light emitting layer431may emit light having a first color, and the second light emitting layer433may emit light having a second color. The first color and the second color may be the same or different from each other.

The first layer432may include an n-type charge generation layer4321and a p-type charge generation layer4322. In such an example, the first electrode410may be the anode electrode, and the second electrode420may be the cathode electrode.

The first layer410may include a first compound432aand a second compound432b. The first compound432aand the second compound432bare described below in detail. As the organic material layer432includes the first compound432aand second compound432b, the organic light emitting element may have high efficiency, long lifespan, and/or low driving voltage.

The first layer432may be a charge generation layer. For example, the organic light emitting element400may include a charge generation layer positioned between the first light emitting layer431and the second light emitting layer433. The charge generation layer may include a p-type charge generation layer432and an n-type charge generation layer4321.

The first stack may further include a functional layer in addition to the first light emitting layer431. For example, the first stack may include a hole injection layer, a first hole transport layer, a first light emitting layer431and a first electron transport layer.

The second stack may further include a functional layer in addition to the second light emitting layer433. For example, the second stack may include a second hole transport layer, a second light emitting layer433, a second electron transport layer, and an electron injection layer.

The hole injection layer may be positioned on the first electrode410as the anode electrode. The first hole transport layer may be positioned on the hole injection layer. The first light emitting layer431may be positioned on the first hole transport layer. The first electron transport layer may be positioned on the first light emitting layer431. The n-type charge generation layer4321may be positioned on the first electron transport layer. The p-type charge generation layer may be positioned on the n-type charge generation layer4321. The second hole transport layer may be positioned on the n-type charge generation layer4321. The second light emitting layer432may be positioned on the second hole transport layer. The second electron transport layer may be positioned on the second light emitting layer432. The electron injection layer may be positioned on the second electron transport layer. In this example, the first layer433may include an n-type charge generation layer4321and a p-type charge generation layer4322. In this example, the first compound432amay be a p dopant of the p-type charge generation layer4322, and the second compound432bmay be an n dopant of the n-type charge generation layer4321.

The hole injection layer may include an amine-based compound. For example, the hole injection layer may include one or more of HATCN (1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile) and NPD (N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the material for the hole injection layer is not limited to those described above, and may include other compounds that may be used as hole injection materials in the field of organic light emitting elements.

The first hole transport layer may include an amine-based compound. For example, the hole transport layer may include one or more of HATCN (1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile) and NPD (N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the material for the first hole transport layer is not limited to those described above, and may include other compounds that may be used as hole transport materials in the field of organic light emitting elements.

The first light emitting layer431may be a fluorescent light emitting layer or a phosphorescent light emitting layer. The fluorescent light emitting layer may include one or more of a boron-based compound, an anthracene-based compound, and a pyrene-based compound. The phosphorescent light emitting layer may include at least one of a carbazole-based compound and an iridium-based compound.

The first electron transport layer may include at least one of an azine-based compound and an imidazole-based compound. For example, the azine-based compound may be TmPyPB (1,3,5-tri(m-pyridin-3-ylphenyl)benzene). The imidazole-based compound may be TPBI (2,2′,2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole)). However, the material for the electron transport layer is not limited to those described above, and may include other compounds that may be used as electron transport materials in the field of organic light emitting elements.

The n-type charge generation layer4321may include the second compound432b. Further, the n-type charge generation layer4321may include a phenanthroline-based compound as the n dopant. The phenanthroline-based compound may be bphen (bathophenanthroline). However, the n dopant that may be used in addition to the second compound432bis not limited to those described above. When the n-type charge generation layer4321includes the second compound432b, the organic light emitting element400may have high efficiency, long lifespan, and/or low driving voltage.

The p-type charge generation layer4322may include the first compound432aas the p dopant. Further, the p-type charge generation layer4322may further include an amine-based compound as the p dopant. The amine-based compound may be NPD (N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the p dopant that may be used in addition to the first compound432ais not limited to those described above. When the p-type charge generation layer4322includes the first compound432a, the organic light emitting element400may have high efficiency, long lifespan, and/or low driving voltage.

The second hole transport layer may include an amine-based compound. For example, the hole transport layer may include one or more of HATCN (1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile) and NPD (N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the material for the second hole transport layer is not limited to those described above, and may include other compounds that may be used as hole transport materials in the field of organic light emitting elements.

The second light emitting layer433may be a fluorescent light emitting layer or a phosphorescent light emitting layer. The fluorescent light emitting layer may include one or more of a boron-based compound, an anthracene-based compound, and a pyrene-based compound. The phosphorescent light emitting layer may include at least one of a carbazole-based compound and an iridium-based compound. The carbazole-based compound may be CBP (4,4′-bis(N-carbazolyl)-1,1′-biphenyl). The iridium-based compound may be Ir(ppy)3(tris(2-phenylpyridine) iridium(III)). However, the material for the light emitting layer is not limited to those described above, and may include other compounds that may be used as light emitting layer materials in the field of organic light emitting elements.

The second electron transport layer may include at least one of an azine-based compound and an imidazole-based compound. For example, the azine-based compound may be TmPyPB (1,3,5-tri(m-pyridin-3-ylphenyl)benzene). The imidazole-based compound may be TPBi (2,2′,2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole)). However, the material for the electron transport layer is not limited to those described above, and may include other compounds that may be used as electron transport materials in the field of organic light emitting elements.

The electron injection layer may include at least one of an azine-based compound and an imidazole-based compound. For example, the electron injection layer may include one or more of LIF and LiQ. However, the material for the electron injection layer is not limited to those described above, and may include other compounds that may be used as electron injection materials in the field of organic light emitting elements.

FIG.6is a cross-sectional view schematically illustrating an organic light emitting element500according to embodiments of the disclosure.

The organic light emitting element500may include a first electrode510, a second electrode520, and an organic material layer530positioned between the first electrode510and the second electrode520.

The organic material layer530may include a first light emitting layer531, a second light emitting layer533, a third light emitting layer535, a first layer532positioned between the first light emitting layer531and the second light emitting layer533, and a charge generation layer534positioned between the second light emitting layer533and the third light emitting layer535. The charge generation layer534may include a second n-type charge generation layer5342and a second p-type charge generation layer5342positioned on the second n-type charge generation layer5342. In other words, the organic light emitting element500may be a tandem type organic light emitting element including three or more light emitting layers. The tandem type organic light emitting element may include a plurality of stacks each including a light emitting layer. For example, the tandem type organic light emitting element may include a first stack including a first light emitting layer531, a second stack including a second light emitting layer533, and a third stack including a third light emitting layer535. In this example, the first stack may include additional functional layers in addition to the first light emitting layer531. Further, the second stack may include additional functional layers in addition to the second light emitting layer533. Further, the third stack may include additional functional layers in addition to the third light emitting layer535.

The first light emitting layer531, the second light emitting layer533, and the third light emitting layer535may be formed of the same material or of different materials. The first light emitting layer531may emit light having a first color, the second light emitting layer533may emit light having a second color, and the third light emitting layer535may emit light having a third color. The first color, the second color, and the third color may be the same or different from each other.

The first layer532may include a first n-type charge generation layer5321and a first p-type charge generation layer5322. In such an example, the first electrode510may be the anode electrode, and the second electrode520may be the cathode electrode.

The first layer532may include a first compound532aand a second compound532b. The first compound532aand the second compound532bare described below in detail. As the organic material layer532includes the first compound532aand second compound532b, the organic light emitting element may have high efficiency, long lifespan, and/or low driving voltage.

The first stack may further include a functional layer in addition to the first light emitting layer531. For example, the first stack may include a hole injection layer, a first hole transport layer, a first light emitting layer531and a first electron transport layer.

The second stack may further include a functional layer in addition to the second light emitting layer533. For example, the second stack may include a second hole transport layer, a second light emitting layer533and a second electron transport layer.

The third stack may further include a functional layer in addition to the third light emitting layer535. For example, the third stack may include a third hole transport layer, a third light emitting layer535, a third electron transport layer, and an electron injection layer.

The hole injection layer may be positioned on the first electrode510as the anode electrode. The first hole transport layer may be positioned on the hole injection layer. The first light emitting layer531may be positioned on the first hole transport layer. The first electron transport layer may be positioned on the first light emitting layer531. The charge generation layer534may include an n-type charge generation layer and a p-type charge generation layer. The first n-type charge generation layer5321may be positioned on the first electron transport layer. The first p-type charge generation layer5322may be positioned on the first n-type charge generation layer5321. The second hole transport layer may be positioned on the first n-type charge generation layer5321. The second light emitting layer533may be positioned on the second hole transport layer. The second electron transport layer may be positioned on the second light emitting layer533. The second n-type charge generation layer5341may be positioned on the second electron transport layer. The second p-type charge generation layer5342may be positioned on the second n-type charge generation layer5341. The third hole transport layer may be positioned on the second p-type charge generation layer5342. The third light emitting layer535may be positioned on the third hole transport layer. The third electron transport layer may be positioned on the third light emitting layer535. The electron injection layer may be positioned on the third electron transport layer. In this example, the first layer532may include a first n-type charge generation layer5321and a first p-type charge generation layer5322. In this example, the first compound532amay be a p dopant of the first p-type charge generation layer5322, and the second compound532bmay be an n dopant of the first n-type charge generation layer5321. The second n-type charge generation layer5341may include an n dopant534b. The n dopant534bmay be the same as or different from the second compound532b. The second p-type charge generation layer5342may include a p dopant534a. The p dopant534amay be the same as or different from the first compound532a.

The hole injection layer may include an amine-based compound. For example, the hole injection layer may include one or more of HATCN (1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile) and NPD (N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the material for the hole injection layer is not limited to those described above, and may include other compounds that may be used as hole injection materials in the field of organic light emitting elements.

The first hole transport layer may include an amine-based compound. For example, the hole transport layer may include one or more of HATCN (1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile) and NPD (N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the material for the first hole transport layer is not limited to those described above, and may include other compounds that may be used as hole transport materials in the field of organic light emitting elements.

The first light emitting layer531may be a fluorescent light emitting layer or a phosphorescent light emitting layer. The fluorescent light emitting layer may include one or more of a boron-based compound, an anthracene-based compound, and a pyrene-based compound. The phosphorescent light emitting layer may include at least one of a carbazole-based compound and an iridium-based compound.

The first electron transport layer may include at least one of an azine-based compound and an imidazole-based compound. For example, the azine-based compound may be TmPyPB (1,3,5-tri(m-pyridin-3-ylphenyl)benzene). The imidazole-based compound may be TPBi (2,2′,2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H benzimidazole)). However, the material for the electron transport layer is not limited to those described above, and may include other compounds that may be used as electron transport materials in the field of organic light emitting elements.

The first n-type charge generation layer5321may include the second compound532b. Further, the first n-type charge generation layer5321may include a phenanthroline-based compound as the n dopant. The phenanthroline-based compound may be bphen (bathophenanthroline). However, the n dopant that may be used in addition to the second compound532bis not limited to those described above. When the first n-type charge generation layer5321includes the second compound532b, the organic light emitting element500may have high efficiency, long lifespan, and/or low driving voltage.

The first p-type charge generation layer5322may include the first compound532aas the p dopant. Further, the first p-type charge generation layer5322may further include an amine-based compound as the p dopant. The amine-based compound may be NPD (N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the p dopant that may be used in addition to the first compound532ais not limited to those described above. When the first p-type charge generation layer5322includes the first compound532a, the organic light emitting element500may have high efficiency, long lifespan, and/or low driving voltage.

The second hole transport layer may include an amine-based compound. For example, the hole transport layer may include one or more of HATCN (1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile) and NPD (N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the material for the second hole transport layer is not limited to those described above, and may include other compounds that may be used as hole transport materials in the field of organic light emitting elements. The second light emitting layer533may be a fluorescent light emitting layer or a phosphorescent light emitting layer. The fluorescent light emitting layer may include one or more of a boron-based compound, an anthracene-based compound, and a pyrene-based compound. The phosphorescent light emitting layer may include at least one of a carbazole-based compound and an iridium-based compound. The carbazole-based compound may be CBP (4,4′-bis(N-carbazolyl)-1,1′-biphenyl). The iridium-based compound may be Ir(ppy)3(tris(2-phenylpyridine) Iridium(III)). However, the material for the light emitting layer is not limited to those described above, and may include other compounds that may be used as light emitting layer materials in the field of organic light emitting elements.

The second electron transport layer may include at least one of an azine-based compound and an imidazole-based compound. For example, the azine-based compound may be TmPyPB (1,3,5-tri(m-pyridin-3-ylphenyl)benzene). The imidazole-based compound may be TPBi (2,2′,2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H benzimidazole)). However, the material for the electron transport layer is not limited to those described above, and may include other compounds that may be used as electron transport materials in the field of organic light emitting elements.

The third hole transport layer may include an amine-based compound. For example, the hole transport layer may include one or more of HATCN (1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile) and NPD (N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine). However, the material for the third hole transport layer is not limited to those described above, and may include other compounds that may be used as hole transport materials in the field of organic light emitting elements.

The third light emitting layer535may be a fluorescent light emitting layer or a phosphorescent light emitting layer. The fluorescent light emitting layer may include one or more of a boron-based compound, an anthracene-based compound, and a pyrene-based compound. The phosphorescent light emitting layer may include at least one of a carbazole-based compound and an iridium-based compound. The carbazole-based compound may be CBP (4,4′-bis(N-carbazolyl)-1,1′-biphenyl). The iridium-based compound may be Ir(ppy)3(tris(2-phenylpyridine) Iridium(III)). However, the material for the light emitting layer is not limited to those described above, and may include other compounds that may be used as light emitting layer materials in the field of organic light emitting elements.

The third electron transport layer may include at least one of an azine-based compound and an imidazole-based compound. For example, the azine-based compound may be TmPyPB (1,3,5-tri(m-pyridin-3-ylphenyl)benzene). The imidazole-based compound may be TPBi (2,2′,2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H benzimidazole)). However, the material for the electron transport layer is not limited to those described above, and may include other compounds that may be used as electron transport materials in the field of organic light emitting elements.

The electron injection layer may include at least one of an azine-based compound and an imidazole-based compound. For example, the electron injection layer may include one or more of LIF and LiQ. However, the material for the electron injection layer is not limited to those described above, and may include other compounds that may be used as electron injection materials in the field of organic light emitting elements.

The first compounds232a,332a,432a, and532aare represented by chemical formula 1 below.

R1and R2are each independently selected from the group consisting of hydrogen, deuterium, tritium, halogen, a cyano group, an alkyl group of C1-C50, a haloalkyl group of C1-C50, an alkoxy group of C1-C30, a haloalkoxy group of C1-C30, an aryl group of C6-C60, a haloaryl group of C6-C60, a heterocyclic group of C2-C60including at least one heteroatom among O, N, S, Si and P, a haloheterocyclic group of C2-C60including at least one heteroatom among O, N, S, Si and P, and malononitrile.

For example, R1and R2may be each independently selected from the group consisting of hydrogen, deuterium, tritium, a cyano group, and malononitrile.

R3is each selected from the group consisting of hydrogen, deuterium, tritium, halogen, a cyano group, a malononitrile group, an alkyl group of C1-C50, a haloalkyl group of C1-C50, an alkoxy group of C1-C30, a haloalkoxy group of C1-C30, an aryl group of C6-C60, a heterocyclic group of C2-C60including at least one heteroatom among O, N, S, Si and P, and a haloheterocyclic group of C2-C60including at least one heteroatom among O, N, S, Si and.

For example, R3may be each independently selected from the group consisting of hydrogen, deuterium, tritium, halogen and a cyano group.

X1to X5are each independently CRaor N, and at least two of X1to X5are CRa.

Rais each independently selected from the group consisting of hydrogen, deuterium, tritium, halogen, an alkyl group of C1-C50, a haloalkyl group of C1-C50, an alkoxy group of C1-C50, and a haloalkoxy group of C1-C50. At least one of Rais selected from the group consisting of halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50. In other words, at least one of Rais an electron withdrawing group (EWG).

For example, Ramay be each independently selected from among hydrogen, deuterium, tritium, halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50. At least one of Ramay be selected from the group consisting of halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50.

When Rais a haloalkyl group, Ramay be a haloalkyl group of C1-C30, a haloalkyl group of C1-C15, a haloalkyl group of C1-C10, or a haloalkyl group of C1-C3.

When Rais a haloalkoxy group, Ramay be a haloalkoxy group of C1-C30, a haloalkoxy group of C1-C15, a haloalkoxy group of C1-C10or a haloalkoxy group of C1-C3.

X6to X10are each independently CRbor N. and at least two of X6to X10are CRb.

Rbis each independently selected from the group consisting of hydrogen, deuterium, tritium, halogen, an alkyl group of C1-C50, a haloalkyl group of C1-C50, an alkoxy group of C1-C50, and a haloalkoxy group of C1-C50. At least one of Rbis selected from the group consisting of halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50. In other words, at least one of Rbis an electron withdrawing group (EWG).

For example, Rbmay be each independently selected from among hydrogen, deuterium, tritium, halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50. At least one of Rbmay be selected from the group consisting of halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50.

When Rbis a haloalkyl group, Rbmay be a haloalkyl group of C1-C50, a haloalkyl group of C1-C15, a haloalkyl group of C1-C10, or a haloalkyl group of C1-C3.

When Rbis a haloalkoxy group, Rbmay be a haloalkoxy group of C1-C50, a haloalkoxy group of C1-C15, a haloalkoxy group of C1-C10, or a haloalkoxy group of C1-C3.

Independently each of R1to R3, Raand Rbin chemical formula 1 may be further substituted. E.g., in case each of R1to R3, Raand Rbin chemical formula 1 is independently selected from an alkyl group, a haloalkyl group, an alkoxy group, a haloalkoxy group, an aryl group, a haloaryl group, a heterocyclic group, and a haloheterocyclic group, this group may be further substituted with one or more substituents selected from the group consisting of deuterium, a nitro group, a cyano group, an amino group, an alkoxy group of C1-C20, a haloalkoxy group of C1-C20, an alkyl group of C1-C20, a haloalkyl group of C1-C20, an alkenyl group of C2-C20, an alkynyl group of C2-C20, an aryl group of C6-C20, an aryl group of C6-C20substituted with deuterium, a fluorenyl group, a heterocyclic group of C2-C20, an alkylsilyl group of C3-C60, an arylsilyl group of Cia-C60, and an alkylarylsilyl group of C8-C60.

The above-described first compounds232a,332a,432a, and532amay be represented by either chemical formula 3 or chemical formula 4 below.

In chemical formula 3 and chemical time4, R1to R3and X1to X10may be the same as R1to R3and X1to X10defined in chemical formula 1 described above.

The above-described first compounds232a,332a,432a, and532amay be represented by either chemical formula 5 or chemical formula 6 below.

Hereinafter, chemical formula 5 and chemical formula 6 are described.

Rcto Rhare each independently selected from the group consisting of hydrogen; deuterium; tritium; halogen; an alkyl group of C1-C50; a haloalkyl group of C1-C50; an alkoxy group of C1-C50; and a haloalkoxy group of C1-C50.

When Rcto Rhare a haloalkyl group, Rcto Rhwhich are a haloalkyl group may be a haloalkyl group of C1-C30, a haloalkyl group of C1-C15, or a haloalkyl group of C1-C10.

When Rcto Rhare a haloalkoxy group, Rcto Rhmay be a haloalkoxy group of C1-C30, a haloalkoxy group of C1-C15, or a haloalkoxy group of C1-C10.

Each Reis independently hydrogen, deuterium, or tritium. For example, Remay be hydrogen. The compounds232a,332a,432a, and532aaccording to embodiments of the disclosure have a structure in which an electron withdrawing group (EWG) is not bonded to carbon that is in an ortho position of carbons bonded to the indacene moiety in the form of a six-membered ring bonded to the indacene moiety. The organic light emitting elements200,300,400, and500including the compounds232a,332a,432a, and532ahaving such a structure have excellent efficiency, a long lifespan, and/or a low driving voltage.

Rfand Rgare each independently selected from the group consisting of hydrogen, deuterium, tritium, halogen, an alkyl group of C1-C50, a haloalkyl group of C1-C50, an alkoxy group of C1-C50, and a haloalkoxy group of C1-C50.

When Rfand Rgare a haloalkyl group, Rfand Rgwhich are a haloalkyl group may be a haloalkyl group of C1-C30, a haloalkyl group of C1-C15, or a haloalkyl group of C1-C10.

When Rfand Rgare a haloalkoxy group, Rfand Rgmay be a haloalkoxy group of C1-C30, a haloalkoxy group of C1-C15, or a haloalkoxy group of C1-C10.

Each Rhis independently hydrogen, deuterium, or tritium. For example, Rhmay be hydrogen. The compounds232a,332a,432a, and532aaccording to embodiments of the disclosure have a structure in which an electron withdrawing group (EWG) is not bonded to carbon that is in an ortho position of carbons bonded to the indacene moiety in the form of a six-membered ring bonded to the indacene moiety. The organic light emitting elements200,300,400, and500including the compounds232a,332a,432a, and532ahaving such a structure have excellent efficiency, a long lifespan, and/or a low driving voltage.

R3is the same as R3to R7defined in chemical formula 1.

Hereinafter, chemical formula 5 is described in more detail.

Rcmay be selected from the group consisting of halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50. In other words, Rcmay be an electron withdrawing group (EWG).

One Rdmay be hydrogen, deuterium, or tritium, and the other Rdmay be selected from the group consisting of halogen, a haloalkyl group of C1-C50and a haloalkoxy group of C1-C50. In this example, one Rdof the two Rds may be an electron withdrawing group (EWG).

In the benzene ring in which Rcand Rdare substituted in chemical formula 5, Rc, which is a para position, is an electron withdrawing group (EWG) in relation to the indacene moiety, and at least one of Rcand Rd, which is an ortho position, is an electron withdrawing group (EWG). In Rband Rd, the electron withdrawing group (EWG) is substituted with a substituent other than a cyano group. The organic light emitting elements200,300,400, and500including the compounds232a,332a,432a, and532ahaving such a structure and represented by chemical formula 5 have excellent efficiency, a long lifespan, and/or a low driving voltage.

Rfmay be selected from the group consisting of halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50. In other words, Rfmay be an electron withdrawing group (EWG).

One Rgmay be hydrogen, deuterium, or tritium, and the other Rgmay be selected from the group consisting of halogen, a haloalkyl group of C1-C50and a haloalkoxy group of C1-C50. In this example, one Rgof the two Rgs may be an electron withdrawing group (EWG).

In another example, two Rgs may be each independently selected from the group consisting of halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50. In this example, both the Rgs may be an electron withdrawing group (EWG). In another example, two Rds may be each independently selected from the group consisting of a halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50. In this example, both the Rds may be an electron withdrawing group (EWG).

In the benzene ring in which Rfand Rgare substituted in chemical formula 5, Rf, which is in a para position in relation to the indacene moiety, may be an electron withdrawing group (EWG), and at least one of Rf, which is in a para position in relation to the indacene moiety, and Rg, which is in a meta position in relation to the indacene moiety, is an electron withdrawing group (EWG). In Rfand Rgthe electron withdrawing group (EWG) does not include a cyano group. The organic light emitting elements200,300,400, and500including the compounds232a,332a,432a, and532ahaving such a structure and represented by chemical formula 5 have excellent efficiency, a long lifespan, and/or a low driving voltage.

Hereinafter, chemical formula 6 is described in more detail.

Rcmay be selected from the group consisting of halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50. In other words, Rcmay be an electron withdrawing group (EWG).

One Rdmay be hydrogen, deuterium, or tritium, and the other Rdmay be selected from the group consisting of halogen, a haloalkyl group of C1-C50and a haloalkoxy group of C1-C50. In this example, one Rdof the two Rds may be an electron withdrawing group (EWG).

In another example, two Rds may be each independently selected from the group consisting of halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50. In this example, both the Rds may be an electron withdrawing group (EWG).

In the benzene ring in which Rcand Rdare substituted in chemical formula 6. Rc, which is in a para position in relation to the indacene moiety, may be an electron withdrawing group (EWG), and at least one of Rc, which is in a para position in relation to the indacene moiety, and Rd, which is in a meta position in relation to the indacene moiety, is an electron withdrawing group (EWG). In Rcand Rd, the electron withdrawing group (EWG) does not include a cyano group. The organic light emitting elements200,300,400, and500including the compounds232a,332a,432a, and532ahaving such a structure and represented in chemical formula 6 have excellent efficiency, a long lifespan, or a low driving voltage.

Rfmay be selected from the group consisting of halogen, a haloalkyl group of C1-C30, and a haloalkoxy group of C1-C50. In other words, Rfmay be an electron withdrawing group (EWG).

One Rhmay be hydrogen, deuterium, or tritium, and the other Rhmay be selected from the group consisting of halogen, a haloalkyl group of C1-C50and a haloalkoxy group of C1-C50. In this example, one Rhof the two R's may be an electron withdrawing group (EWG).

In another example, two Rhs may be each independently selected from the group consisting of halogen, a haloalkyl group of C1-C50, and a haloalkoxy group of C1-C50. In this example, both the Rhs may be an electron withdrawing group (EWG).

In the benzene ring in which Rfand Rbare substituted in chemical formula 6, Rf, which is in a para position in relation to the indacene moiety, may be an electron withdrawing group (EWG), and at least one of Rf, which is in a para position in relation to the indacene moiety, and Rg, which is in a meta position in relation to the indacene moiety, is an electron withdrawing group (EWG). In Rfand Rg, the electron withdrawing group (EWG) does not include a cyano group. The organic light emitting elements200,300,400, and500including the compounds232a,332a,432a, and532ahaving such a structure and represented in chemical formula 6 have excellent efficiency, a long lifespan, and/or a low driving voltage.

In Rcto Rhin chemical formulas 5 and 6, in the haloalkyl group and haloalkoxy group, at least one substituent selected from the group consisting of deuterium, a nitro group, a cyano group, an amino group, an alkoxy group of C1-C20, a haloalkoxy group of C1-C20, an alkyl group of C1-C20, a haloalkyl group of C1-C20, an alkenyl group of C2-C20, an alkynyl group of C2-C20, an aryl group of C6-C20, an aryl group of C6-C20substituted with deuterium, a fluorenyl group, a heterocyclic group of C2-C20, an alkylsilyl group of C3-C60, an arylsilyl group of C18-C60, and an alkylarylsilyl group of C8-C60may be further substituted.

The above-described first compounds232a,332a,432a, and532amay be represented by any one of chemical formula 7 to chemical formula 16 below. More specifically, the compound represented by chemical formula 3 described above may be represented by any one of chemical formulas 7 to 11, and the compound represented by chemical formula 4 described above may be represented by any one of chemical formulas 12 to 16.

Hereinafter, chemical formulas 7 to chemical formula 16 are described.

Remay be each independently selected from hydrogen, deuterium, or tritium.

The compounds232a,332a,432a, and532aaccording to embodiments of the disclosure have a structure in which an electron withdrawing group (EWG) is not bonded to carbon that is an ortho position of carbons bonded to the indacene moiety in form of a six-membered ring bonded to the indacene moiety. The organic light emitting elements200,300,400, and500including the compounds232a,332a,432a, and532ahaving such a structure have excellent efficiency, a long lifespan, and/or a low driving voltage.

In chemical formula 7 to chemical formula 16 described above, at least one electron withdrawing group (EWG) is substituted at the heterocyclic group bonded to the indacene moiety. The organic light emitting elements200,300,400, and500including the compounds232a,332a,432a, and532ahaving such a structure have excellent efficiency, a long lifespan, and/or a low driving voltage.

The first compounds232a,332a,432a, and532amay be one or more of the following compounds.

The second compounds232b,332b,432b, and532bare represented by chemical formula 2 below.

R1to R6are each independently selected from the group consisting of hydrogen, deuterium, tritium, halogen, cyano group, nitro group, aryl group of C6-C60, a fluorenyl group, a heterocyclic group of C2-C60containing at least one heteroatom of O, N, S, Si, and P, a fused ring group of an aliphatic ring of C3-C60and an aromatic ring of C6-C60, an alkyl group of C1-C50, an alkenyl group of C2-C20, an alkynyl group of C2-C20, an alkoxy group of C1-C30, an aryloxy group of C8-C3, an alkylsilyl group of C3-C60, an arylsilyl group of C18-C60, and an alkylarylsilyl group of C8-C60.

When R1to R6are aryl groups, the aryl groups may be each independently an aryl group of C6-C60, an aryl group of C8-C50, or an aryl group of C6-C40.

When R1to R6are heterocyclic groups containing at least one heteroatom of O, N, S, Si, and P, the heterocyclic groups may each independently be a heterocyclic group of C6-C60, a heterocyclic group of C6-C50, or a heterocyclic group of C6-C40.

An1and Ar2are each independently selected from the group consisting of hydrogen, deuterium, tritium, halogen, cyano group, nitro group, aryl group of C6-C60, a fluorenyl group, a heterocyclic group of C2-C60containing at least one heteroatom of O, N, S, Si, and P, a fused ring group of an aliphatic ring of C3-C60and an aromatic ring of C6-C60, an alkyl group of C1-C50, an alkenyl group of C2-C20, an alkynyl group of C2-C20, an alkoxy group of C1-C30, an aryloxy group of C6-C30, an alkylsilyl group of C3-C60, an arylsilyl group of C18-C60, and an alkylarylsilyl group of C8-C60.

When Ar1and Ar2are aryl groups, the aryl groups may be each independently an aryl group of C6-C60, an aryl group of C6-C50, or an aryl group of C6-C40.

When Ar1and Ar2are heterocyclic groups containing at least one heteroatom of O, N, S, Si, and P, the heterocyclic groups may each independently be a heterocyclic group of C6-C60, a heterocyclic group of C6-C50, or a heterocyclic group of C6-C40.

L is selected from the group consisting of a divalent heterocyclic group of C2-C60containing an arylene group of C6-C60, a fluorenyl group, a divalent heterocyclic group of C2-C60containing at least one heteroatom of O, N, S, Si, and P, and a divalent fused ring group of an aliphatic ring of C3-C60and an aromatic ring of C6-C60.

In R1to R6, Ar1, Ar2, and L in chemical formula 3, the alkyl group, the fluorenyl group, the heterocyclic group, the fused ring group, the arylene group, the fluorenyl group, the divalent heterocyclic group, and the divalent fused ring group each may be additionally substituted with one or more substituents selected from the group consisting of deuterium, a nitro group, a cyano group, a halogen group, an amino group, an alkoxyl group of C1-C20, an alkyl group of C1-C20, an alkenyl group of C2-C20, an alkynyl group of C2-C20, an aryl group of C6-C20, an aryl group of C6-C20substituted with deuterium, a fluorenyl group, a heterocyclic group of C2-C20, an alkylsilyl group of C3-C60, an arylsilyl group of Cia-C60, and an alkylarylsilyl group of C8-C60.

As the organic material layers230,330,430, and530of the organic light emitting elements200,300,400, and500include the second compounds232a,332b,432b, and532b, the organic light emitting elements may have excellent efficiency, long lifespan or low driving voltage.

The second compounds232b,332b,432b, and532bmay include two or more types of compounds having different molecular structures. For example, the second compounds232b,332b,432b, and532bmay include a third compound and a fourth compound having different molecular structures.

The third compound may be represented by chemical formula 2 described above, and may be a compound in which Ar2is not phenanthroline in chemical formula 2. In other words, the third compound may be selected from among compounds other than compounds in which Ar2is phenanthroline among the compounds represented by chemical formula 2 described above.

The fourth compound may be represented by chemical formula 2 described above, and may be a compound in which Ar2is phenanthroline. In other words, the fourth compound may be selected from among compounds in which Ar2is phenanthroline among the compounds represented by chemical formula 2.

When the second compounds232b,332b,432b, and532binclude the above-described third and fourth compounds, the organic light emitting element may have excellent efficiency, long lifespan, or low driving voltage.

The second compounds232b,332b,432b, and532bmay be one or more among the compounds described below.

For example, the third compound may be one or more of compounds B1 to B40 described above. Further, the fourth compound may be one or more of the above compounds C1 to C20.

Other embodiments of the disclosure may provide a display device. The display device may include the organic light emitting elements200,300,400, and500described above with reference toFIGS.1to5.

Embodiments of the disclosure described above are briefly described below.

An organic light emitting element200,300,400, or500according to embodiments of the disclosure may comprise a first electrode210,310,410, or510, a second electrode220,320,420, or520, and an organic material layer230,330,430, or530. The organic material layer230,330,430, or530may include a first compound232a,332a,432a, or532arepresented by chemical formula 1 described above. The organic material layer230,330,430, or530may include a second compound232b,332b,432b, or532brepresented by chemical formula 2 described above.

The organic material layer330,430, or530may include a first light emitting layer331,431, or531and a first layer332,432, or532. The first layer332,432, or532may include a first compound332a,432a, or532aand a second compound332b,432b, or532b.

The organic material layer330,430, or530may include a second light emitting layer333,433, or533, and the first layer332,432, or532may be positioned between the first light emitting layer331,431, or531and the second light emitting layer333,433, or533.

The first layer332or432may be a charge generation layer. The first layer432or532may include an n-type charge generation layer4321and a p-type charge generation layer4322. The n-type charge generation layer4321may include the second compound432b. The p-type charge generation layer4322may include the first compound432a.

The first electrode410may be an anode electrode and the second electrode420may be a cathode electrode. The n-type charge generation layer4321may be positioned on the first electrode410, and the p-type charge generation layer4322may be positioned on the n-type charge generation layer4321.

The organic material layer530may include a third light emitting layer535and a charge generation layer534positioned between the second light emitting layer533and the third light emitting layer535.

The display device100according to embodiments of the disclosure includes an organic light emitting element200,300,400, or500.

An example of manufacturing an organic light emitting element according to embodiments of the disclosure are described below in detail with reference to embodiments thereof, but embodiments of the disclosure are not limited to the following embodiments.

COMPOUND SYNTHESIS EXAMPLES

Preparation Example 1-1. Synthesis of Compound 3-A

23.9 g (76.3 mmol) of 2,2′-(4,6-dibromo-1,3-phenylene) diacetonitrile, 300 mL of toluene, 15.3 mmol of copper iodide, 15.3 mmol of tetrakistriphenylphosphine palladium, 1400 mmol of diisopropylamine, and 228.9 mmol of 4-ethynyl-2-fluoro-1-(trifluoromethyl)benzene were mixed, heated to 100° ° C., and stirred for 2 hours. After the reaction was complete, 200 mL of the solvent was distilled off, and the reaction solution returned to room temperature was filtered to obtain a solid. After dissolving the solid in chloroform and extracting with water, magnesium sulfate and acid clay were added and the solution obtained was stirred for one hour. After filtering the stirred solution, the solvent was distilled off again, and recrystallization was performed twice with tetrahydrofuran/ethanol to obtain 15.3 g of compound 3-A (yield 38%, MS[M+H]=529).

Preparation Example 1-2. Synthesis of Compound 3-B

7.7 g (14.6 mmol) of 3-A, 100 mL of 1,4-dioxane, 87.6 mmol of diphenyl sulfoxide, 2.9 mmol of copper bromide (II), and 2.9 mmol of palladium acetate were mixed, heated to 100° C., and stirred for 5 hours. After the reaction was complete, the solvent was distilled off, the residue was dissolved in chloroform, acid clay was added, and the solution obtained was stirred for one hour. After filtering the stirred solution, the solvent was distilled off again and reverse-precipitation was performed using hexane to obtain a solid. The obtained solid was recrystallized with tetrahydrofuran/hexane and filtered to obtain 3.4 g of compound 3-B (yield 42%, MS [M+H]=557).

Preparation Example 1-3. Synthesis of Compound 3

2.9 g (5.2 mmol) of 3-B, 90 mL of dichloromethane, and 36.4 mmol of malononitrile were added and cooled to 0 C°. After slowly adding 26.0 mmol of titanium chloride (IV) at ° C., the mixture was stirred for 1 hour while maintaining the temperature at 0° C. 36.4 mmol of pyridine was dissolved in 52 mL of dichloromethane, and then added slowly to the mixture at 0° C., and then the mixture was stirred for one hour while maintaining the temperature. After the reaction was complete, 36.4 mmol of acetic acid was added and the mixture was stirred for an additional 30 minutes. After the reaction was complete the solution obtained was extracted with water, the organic layer was reverse-precipitated in hexane to obtain a solid. The obtained solid was extracted with acetonitrile and filtered to obtain a filtrate. After adding magnesium sulfate and acid clay to the obtained filtrate, and the solution obtained was stirred for 30 minutes. After filtering the solution, it was recrystallized with acetonitrile/toluene and washed with toluene. The obtained solid was recrystallized again using acetonitrile/tert-butylmethylether and purified by sublimation, obtaining 1.5 g of compound 3 (yield 45%, MS[M+H]=653).

Preparation Example 2-1. Synthesis of Compound 22-A

33.1 g (94.6 mmol) of 2,2′-(1,3-dibromo-2.5-difluoro-4,6-phenylene) diacetonitrile, 400 mL of toluene, 18.9 mmol of copper iodide, 18.9 mmol of tetrakistriphenylphosphine palladium, 473 mmol of diisopropylamine, and 283.8 mmol of 4-ethynyl-1-fluoro-2-(trifluoromethyl)benzene were mixed, heated to 100° C. and stirred for 2 hours. After the reaction, 300 mL of the solvent was distilled, and the reaction solution returned to room temperature was filtered to obtain a solid. After dissolving the solid in chloroform and extracting with water, magnesium sulfate and acid clay were added and stirred for one hour. After filtering the stirred solution, the solvent was distilled off again, and recrystallization was performed twice with tetrahydrofuran/ethanol to obtain 16.0 g of compound 22-A (yield 30%, MS[M+H]=565).

Preparation Example 2-2. Synthesis of Compound 22-B

3.7 g (24.3 mmol) of 22-A, 180 mL of 1,4-dioxane, 145.8 mmol of diphenyl sulfoxide, 4.9 mmol of copper bromide (II), and 4.9 mmol of palladium acetate were mixed, heated to 100° ° C., and stirred for 5 hours. After the reaction, the solvent was distilled off, dissolved in chloroform, acid clay was added, and stirred for one hour. After filtering the stirred solution, the solvent was distilled off again and reverse-precipitated was performed using hexane to obtain a solid. The obtained solid was recrystallized with tetrahydrofuran/hexane and filtered to obtain 3.6 g of compound 22-B (yield 25%, MS [M+H]=593).

Preparation Example 2-3. Synthesis of Compound 22

3.0 g (5.1 mmol) of 22-B, 100 mL of dichloromethane, and 35.7 mmol of malononitrile were added and cooled to 0 C°. After slowly adding 25.5 mmol of titanium chloride (IV) ° C., it was stirred for 1 hour while remaining at 0° C. 35.7 mmol of pyridine was dissolved in 30 mL of dichloromethane, and then added slowly at 0° C., and then it was stirred for one hour while maintaining the temperature. After the reaction was complete, 35.7 mmol of acetic acid was added and stirred for an additional 30 minutes. After the reaction solution was extracted with water, the organic layer was reverse-precipitated in hexane to obtain a solid. The obtained solid was filtered through acetonitrile, and magnesium sulfate and acid clay were added, followed by stirring for 30 minutes. After filtering the solution, it was recrystallized with acetonitrile/toluene and washed with toluene. The obtained solid was recrystallized again using acetonitrile/tert-butylmethylether and purified by sublimation, obtaining 1.0 g of compound 22 (yield 28%, MS[M+H]=689).

Preparation Example 3-1. Synthesis of Compound 31-A

31.7 g (101.0 mmol) of 2,2′-(1,4-dibromo-3,6-phenylene) diacetonitrile, 350 mL of toluene, 20.2 mmol of copper iodide, 20.2 mmol of tetrakistriphenylphosphine palladium, 505 mmol of diisopropylamine, and 303 mmol of 4-ethynyl-2-fluoro-1-(trifluoromethyl)benzene were mixed, heated to 100° C., and stirred for 2 hours. After the reaction was complete, 200 ml of the solvent was distilled off, and the reaction solution returned to room temperature was filtered to obtain a solid. After dissolving the solid in chloroform and extracting with water, magnesium sulfate and acid clay were added and the solution obtained was stirred for one hour. After filtering the stirred solution, the solvent was distilled off again, and recrystallization was performed twice with tetrahydrofuran/ethanol to obtain 24.0 g of compound 31-A (yield 45%, MS[M+H]=529).

Preparation Example 3-2. Synthesis of Compound 31-B

18.7 g (35.4 mmol) of 31-A, 250 ml of 1,4-dioxane, 212.4 mmol of diphenyl sulfoxide, 7.1 mmol of copper bromide (II), and 7.1 mmol of palladium acetate were mixed, heated to 100° C., and stirred for 5 hours. After the reaction was complete, the solvent was distilled off, the residue was dissolved in chloroform, acid clay was added, and the solution obtained was stirred for one hour. After filtering the stirred solution, the solvent was distilled off again and reverse-precipitation was performed using hexane to obtain a solid. The obtained solid was recrystallized with tetrahydrofuran/hexane and filtered to obtain 6.5 g of compound 31-B (yield 33%, MS [M+H]=557).

Preparation Example 3-3. Synthesis of Compound 31

4.9 g (8.8 mmol) of 31-B, 150 ml of dichloromethane, and 61.6 mmol of malononitrile were added and cooled to 0 C°. After slowly adding 44.0 mmol of titanium chloride (IV) at 0° C., the mixture was stirred for 1 hour while maintaining the temperature at 0° C. 61.6 mmol of pyridine was dissolved in 50 ml of dichloromethane, and then added slowly to the mixture at 0° ° C., and then the mixture was stirred for one hour while maintaining the temperature. After the reaction was complete, 61.6 mmol of acetic acid was added and the solution obtained stirred for an additional 30 minutes. After the reaction was complete the solution was extracted with water, the organic layer was reverse-precipitated in hexane to obtain a solid. The obtained solid was extracted with acetonitrile and filtered to obtain a filtrate. After adding magnesium sulfate and acid clay to the obtained filtrate, and the solution obtained was stirred for 30 minutes. After filtering the solution, it was recrystallized with acetonitrile/toluene and washed with toluene. The obtained solid was recrystallized again using acetonitrile/tert-butylmethylether and purified by sublimation, obtaining 2.0 g of compound 31 (yield 35%, MS[M+H]=653).

Preparation Example 4-1. Synthesis of Compound 65-A

29.4 g (93.5 mmol) of 2,2′-(4,6-dibromo-1,3-phenylene) diacetonitrile, 350 mL of toluene, 18.7 mmol of copper iodide, 18.7 mmol of tetrakistriphenylphosphine palladium, 467.5 mmol of diisopropylamine, and 280.5 mmol of 4-ethynyl-2,6-difluoropyridine were mixed, heated to 100° C., and stirred for 2 hours. After the reaction was complete, 200 mL of the solvent was distilled off, and the reaction solution returned to room temperature was filtered to obtain a solid. After dissolving the solid in chloroform and extracting with water, magnesium sulfate and acid clay were added and stirred for one hour. After filtering the stirred solution, the solvent was distilled off again, and recrystallization was performed twice with tetrahydrofuran/ethanol to obtain 18.5 g of compound 65-A (yield 46%, MS[M+H]=431).

Preparation Example 4-2. Synthesis of Compound 65-B

14.1 g (32.8 mmol) of 65-A, 180 mL of 1,4-dioxane, 196.8 mmol of diphenyl sulfoxide, 6.6 mmol of copper bromide (II), and 6.6 mmol of palladium acetate were mixed, heated to 100° C., and stirred for 5 hours. After the reaction was complete, the solvent was distilled off, the residue was dissolved in chloroform, acid clay was added, and the solution obtained was stirred for one hour. After filtering the stirred solution, the solvent was distilled off again and reverse-precipitation was performed using hexane to obtain a solid. The obtained solid was recrystallized with tetrahydrofuran/hexane and filtered to obtain 6.0 g of compound 65-B (yield 40%, MS [M+H]=459).

Preparation Example 4-3. Synthesis of Compound 65

4.2 g (9.2 mmol) of 65-B, 130 mL of dichloromethane, and 64.4 mmol of malononitrile were added and cooled to 0° C. After slowly adding 46.0 mmol of titanium chloride (IV) at 0° C., the mixture was stirred for 1 hour while maintaining the temperature at 0° C. 64.4 mmol of pyridine was dissolved in 45 mL of dichloromethane, and then added slowly to the mixture at 0° C., and then the mixture was stirred for one hour while maintaining the temperature at 0° C. After the reaction was complete, 64.4 mmol of acetic acid was added and the solution obtained was stirred for an additional 30 minutes. After the reaction was complete the solution was extracted with water, the organic layer was reverse-precipitated in hexane to obtain a solid. The obtained solid was extracted with acetonitrile and filtered to obtain a filtrate. After adding magnesium sulfate and acid clay to the obtained filtrate, and the solution obtained was stirred for 30 minutes. After filtering the solution, it was recrystallized with acetonitrile/toluene and washed with toluene. The obtained solid was recrystallized again using acetonitrile/tert-butylmethylether and purified by sublimation, obtaining 2.3 g of compound 65 (yield 45%, MS[M+H]=555).

Preparation Example 5. Synthesis of Compound B7

19.5 g (42.7 mmol) of B7-A, 200 ml of toluene, 60 ml of ethanol, 42.7 mmol of 9-bromo-phenanthrene, 4 M potassium carbonate solution (30 ml), and 4.3 mmol of tetrakistriphenylphosphine palladium were mixed, heated and refluxed and stirred for 12 hours. After reducing the temperature to room temperature and adding 100 ml of water to terminate the reaction, the mixture was recrystallized using dichloromethane and filtered, obtaining 13 g of compound B7 (yield: 60%, MS[M+H]+=509).

[Manufacturing Evaluation of Organic Light Emitting Element]

In Tables 1 and 2 above, HATCN is 1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile, Bphen is bathophenanthroline, and PD1 to PD4 are as follows.

Referring to Tables 1 and 2, the organic light emitting element of the embodiment which uses the first compound of the disclosure in the p-type charge generation layer and the second compound in the n-type charge generation layer has better efficiency, longer lifespan, and lower driving voltage than the organic light emitting element of the comparative example.

Referring to Table 2, the embodiments (embodiments 2-4, 7, 10-12, 15-17, and 20-22) in which the n-type charge generation layer simultaneously includes one type of third compound and one type of fourth compound have more excellent efficiency, a longer lifespan, or a lower driving voltage than the embodiments (embodiments 1, 5, 6, 8, 9, 13, 14, 18, and 19) in which only one type of second compound is included.

More specifically, comparison between embodiment 1 and embodiment 2 reveals that embodiment 2 in which the n-type charge generation layer includes Bphene which is the third compound and C2 which is the fourth compound has more excellent efficiency, a longer lifespan, and lower driving voltage than embodiment 1 in which only Bphen is included. It may be identified that this tendency is also shown by comparing embodiment 4 and embodiment 5, and similar tendencies are observed in other embodiments.