Organic electroluminescence device and polycyclic compound for organic electroluminescence device

Abstract

Organic electroluminescent devices and polycyclic compounds for use in organic electroluminescent devices are disclosed. One or more embodiments of the organic electroluminescent device include a first electrode, a hole transport region disposed on the first electrode, an emission layer disposed on the hole transport region, an electron transport region disposed on the emission layer, and a second electrode disposed on the electron transport region, wherein the emission layer comprises a polycyclic compound represented by Formula 1, thereby exhibiting high emission efficiency: Formula 1 where Y is O or S.

Description

[0001] This application claims priority and benefit to Korean Patent Application No. 10-2020-0064095, filed on May 28, 2020, the entire contents of which are incorporated herein by reference. Technical Field

[0002] Hereinafter, one or more aspects of embodiments of the present disclosure relate to an organic electroluminescent device and a polycyclic compound for use in an organic electroluminescent device. Background Technology

[0003] Recently, there has been active development of organic electroluminescent displays (OLEDs) as image displays. Unlike liquid crystal displays (LCDs), OLEDs are self-emissive displays in which holes and electrons injected from the first and second electrodes recombine in the emitting layer, and the emitting layer contains luminescent materials composed of organic compounds that emit light to achieve image display.

[0004] When applying organic light-emitting devices (OLEDs) to displays, it is required (or desired) to reduce the driving voltage of OLEDs and improve their emission efficiency and lifetime. There is also a continuous demand (or expectation) to develop materials for OLEDs that can reliably achieve these properties.

[0005] In particular, in order to realize highly efficient organic electroluminescent devices, techniques are being developed that utilize phosphorescence emission using triplet energy or delayed fluorescence emission utilizing the phenomenon of generating singlet excitons through collisions of triplet excitons (triplet-triplet annihilation, TTA). Materials for thermally activated delayed fluorescence (TADF) that utilize the delayed fluorescence phenomenon are also being developed. Summary of the Invention

[0006] One or more aspects of embodiments of this disclosure relate to an organic electroluminescent device having long lifetime and high efficiency, and the polycyclic compound used therein.

[0007] One or more aspects of the embodiments of this disclosure also provide an organic electroluminescent device comprising a thermally activated delayed fluorescence emission material and a polycyclic compound used as the thermally activated delayed fluorescence emission material.

[0008] In one or more embodiments, a polycyclic compound represented by the following Formula 1 is provided:

[0009] Formula 1

[0010]

[0011] In Formula 1, Y can be O or S; rings D to H can each be independently an aryl ring with 6 to 30 cyclic carbon atoms, substituted or unsubstituted, or a heteroaryl ring with 2 to 30 cyclic carbon atoms, and optionally, rings E and F, F and H, G and E, G and Ar, and D and Ar can each be independently linked to each other to form a ring; and Ar can be an aryl ring with 6 to 30 cyclic carbon atoms, substituted or unsubstituted, or a heteroaryl ring with 2 to 30 cyclic carbon atoms, substituted or unsubstituted.

[0012] In one or more embodiments, Ar can be represented by the following Equation 2:

[0013] Formula 2

[0014]

[0015] In Formula 2, Ra can be a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted thiol group, a substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, a substituted or unsubstituted aryl group with 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 30 cyclic carbon atoms, and optionally, it can be combined with an adjacent group to form a ring; and "b" can be an integer from 0 to 5.

[0016] In one or more embodiments, Equation 1 can be represented by Equation 3 below:

[0017] Formula 3

[0018]

[0019] In Formula 3, R1 to R5 can each be independently a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted thiol group, a substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, a substituted or unsubstituted aryl group with 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 30 cyclic carbon atoms, and optionally, can be combined with adjacent groups to form a ring; "e" to "h" can each be independently an integer from 0 to 4; and Y and Ar are the same as defined in Formula 1.

[0020] In one or more embodiments, R1 to R5 may each be independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted arylamine group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted carbazole group, a substituted or unsubstituted dibenzofuran group, or a substituted or unsubstituted dibenzothiophene group.

[0021] In one or more embodiments, at least one of R1 to R5 may include a substituted or unsubstituted amino group or a substituted or unsubstituted N-containing heteroaryl group.

[0022] In one or more embodiments, equation 3 can be represented by equation 4-1 or equation 4-2 below:

[0023] Equation 4-1

[0024]

[0025] Equation 4-2

[0026]

[0027] In Formulas 4-1 and 4-2, Ra can be a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted thiol group, a substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, a substituted or unsubstituted aryl group with 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 30 cyclic carbon atoms, and optionally, can be combined with adjacent groups to form a ring; “b” can be an integer from 0 to 5; “e′” and “f′” can each be an integer from 0 to 3 independently; and Y, R1 to R5 and “e” to “h” are the same as those defined in Formula 3.

[0028] In one or more embodiments, equation 4-1 can be represented by equation 5-1 or equation 5-2 below:

[0029] Formula 5-1

[0030]

[0031] Formula 5-2

[0032]

[0033] In Formulas 5-1 and 5-2, R4′ and R5′ can each be independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted arylamine group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted carbazole group, a substituted or unsubstituted dibenzofuran group, or a substituted or unsubstituted dibenzothiophene group; g′ and h′ can each be independently integers from 0 to 3; and Y, R1 to R5, Ra, “b” and “e” to “h” are the same as those defined in Formula 4-1.

[0034] In one or more embodiments, the polycyclic compound represented by Formula 1 may be at least one of the compounds represented in Compound Group 1.

[0035] In one or more embodiments of this disclosure, an organic electroluminescent device is provided, the organic electroluminescent device comprising: a first electrode; a hole transport region disposed (e.g., provided) on the first electrode; an emission layer disposed on the hole transport region; an electron transport region disposed on the emission layer; and a second electrode disposed on the electron transport region, wherein both the first electrode and the second electrode independently comprise at least one selected from Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, In, Sn, Zn, two or more compounds selected therefrom, mixtures of two or more selected therefrom, and oxides thereof, and the emission layer comprises a polycyclic compound.

[0036] In one or more embodiments, the emitting layer may emit delayed fluorescence.

[0037] In one or more embodiments, the emission layer may be a delayed fluorescence emission layer comprising a first compound and a second compound, and the first compound may include a polycyclic compound.

[0038] In one or more embodiments, the emitting layer may be a thermally activated delayed fluorescence emitting layer that emits (e.g., to emit) blue light. Attached Figure Description

[0039] The accompanying drawings are included to provide a further understanding of this disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of this disclosure and, together with the description, serve to explain the principles of this disclosure. In the drawings:

[0040] Figure 1 This is a schematic cross-sectional view of an organic electroluminescent device according to one or more embodiments of the present disclosure;

[0041] Figure 2 This is a schematic cross-sectional view of an organic electroluminescent device according to one or more embodiments of the present disclosure;

[0042] Figure 3 This is a schematic cross-sectional view illustrating an organic electroluminescent device according to one or more embodiments of the present disclosure; and

[0043] Figure 4 This is a schematic cross-sectional view of an organic electroluminescent device according to one or more embodiments of the present disclosure. Detailed Implementation

[0044] This disclosure can have various modifications and can be implemented in different forms, and exemplary embodiments will be explained in more detail with reference to the accompanying drawings. However, this disclosure can be implemented in different forms and should not be construed as limited to the embodiments set forth herein. Rather, all modifications, equivalents, and alternatives that are included within the spirit and scope of this disclosure should be included herein.

[0045] It will be understood that when an element (or region, layer, part, etc.) is referred to as being "on" another element, "connected to" or "integrated into" another element, the element (or region, layer, part, etc.) may be directly on, directly connected to or directly integrated into the other element (without any intermediate elements in between), or there may be one or more third intermediate elements.

[0046] The same reference numerals always denote the same elements. Furthermore, in the accompanying drawings, the thickness, scale, and dimensions of the constituent elements are exaggerated to effectively explain the technical content.

[0047] The term "and / or" includes one or more combinations that can be defined by the relevant elements. When expressions such as "at least one of...", "one of...", and "selected from..." are placed before or after a list of elements, they modify the entire list of elements, not individual elements within that list. Furthermore, the word "may" is used in describing embodiments of this disclosure to refer to "one or more embodiments of this disclosure".

[0048] It will be understood that although the terms “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. Thus, without departing from the teachings of this disclosure, a first element may be referred to as a second element. Similarly, a second element may be referred to as a first element. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form as well.

[0049] Furthermore, the terms "below," "under," "above," and "over" are used to explain the relationships between the elements shown in the accompanying drawings. These terms are relative concepts and are interpreted based on the directions shown in the figures.

[0050] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It will also be understood that terms (such as those defined in a general dictionary) shall be interpreted as having a meaning consistent with their meaning in the context of the relevant field, and not as having an idealized or overly formal meaning, unless expressly defined herein.

[0051] It will also be understood that when the terms “comprising” and / or “including” and variations thereof are used in this specification, it indicates the presence of the stated features, numbers, steps, operations, elements, parts, or combinations thereof, but does not exclude the presence or addition of one or more other features, numbers, steps, operations, elements, parts, or combinations thereof.

[0052] In the following description, an organic electroluminescent device according to one or more embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0053] Figures 1 to 4 This is a schematic cross-sectional view illustrating an organic electroluminescent device according to an exemplary embodiment of the present disclosure. (Refer to...) Figures 1 to 4 In an organic electroluminescent device 10 according to one or more embodiments, a first electrode EL1 and a second electrode EL2 are disposed opposite to each other, and an emission layer EML may be disposed between the first electrode EL1 and the second electrode EL2.

[0054] In one or more embodiments, in addition to the emitter layer EML, the organic electroluminescent device 10 of one or more embodiments further includes a plurality of functional layers located between the first electrode EL1 and the second electrode EL2. The plurality of functional layers may include a hole transport region HTR and an electron transport region ETR. For example, the organic electroluminescent device 10 of one or more embodiments may include a first electrode EL1, a hole transport region HTR, an emitter layer EML, an electron transport region ETR, and a second electrode EL2 stacked sequentially. In one or more embodiments, the organic electroluminescent device 10 of one or more embodiments may include a capping layer CPL disposed on the second electrode EL2.

[0055] One or more embodiments of the organic electroluminescent device 10 include a polycyclic compound, as explained below, in the emitter layer EML disposed between the first electrode EL1 and the second electrode EL2. However, one or more embodiments of this disclosure are not limited thereto, and in addition to the emitter layer EML, the organic electroluminescent device 10 may include a polycyclic compound, as explained below, in the hole transport region HTR or the electron transport region ETR, or in the capping layer CPL disposed on the second electrode EL2, the hole transport region HTR or the electron transport region ETR being part of a plurality of functional layers disposed between the first electrode EL1 and the second electrode EL2.

[0056] At the same time, when with Figure 1 In comparison, Figure 2A cross-sectional view of an organic electroluminescent device 10 according to one or more embodiments is shown, wherein the hole transport region HTR includes a hole injection layer HIL and a hole transport layer HTL, and the electron transport region ETR includes an electron injection layer EIL and an electron transport layer ETL. In one or more embodiments, when combined with... Figure 1 In comparison, Figure 3 A cross-sectional view of an organic electroluminescent device 10 according to one or more embodiments is shown, wherein the hole transport region HTR includes a hole injection layer HIL, a hole transport layer HTL, and an electron blocking layer EBL; the electron transport region ETR includes an electron injection layer EIL, an electron transport layer ETL, and a hole blocking layer HBL. When compared with... Figure 2 In comparison, Figure 4 A cross-sectional view of an organic electroluminescent device 10 according to one or more embodiments is shown. The organic electroluminescent device 10 also includes a capping layer CPL disposed on a second electrode EL2.

[0057] The first electrode EL1 is conductive. The first electrode EL1 can be formed using a metal alloy or any suitable conductive compound. The first electrode EL1 can be a pixel electrode or an anode. The first electrode EL1 can be a transmissive electrode, a transmissive-reflective electrode, or a reflective electrode. If the first electrode EL1 is a transmissive electrode, it can be formed using a transparent metal oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), and / or indium tin zinc oxide (ITZO). If the first electrode EL1 is a transmissive-reflective electrode or a reflective electrode, it can include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, In, Sn, Zn, compounds thereof, mixtures thereof (e.g., mixtures of Ag and Mg, LiF / Ca, or LiF / Al), or oxides thereof. In some embodiments, the first electrode EL1 may have a structure comprising multiple layers, including a reflective or transmissive layer formed using any of the materials described above, and a transmissive conductive layer formed using ITO, IZO, ZnO, and / or ITZO. For example, the first electrode EL1 may include a three-layer structure of ITO / Ag / ITO. However, embodiments of this disclosure are not limited thereto. The thickness of the first electrode EL1 may be approximately up to approximately (for example, approximately) up to approximately ).

[0058] The hole transport region HTR is disposed on the first electrode EL1. The hole transport region HTR may include at least one of the hole injection layer HIL, the hole transport layer HTL, the hole buffer layer, and the electron blocking layer EBL.

[0059] The hole transport region (HTR) can have a single layer (e.g., a single-layer structure) formed using a single material (e.g., composed of a single material), a single layer formed using multiple different materials, or a multilayer structure including multiple layers formed using multiple different materials.

[0060] For example, the hole transport region HTR can have a single-layer structure of a hole injection layer HIL or a hole transport layer HTL, or it can have a single-layer structure formed using a hole injection material and a hole transport material. In some embodiments, the hole transport region HTR can have a single-layer structure formed using a variety of different materials, or a structure of hole injection layer HIL / hole transport layer HTL, hole injection layer HIL / hole transport layer HTL / hole buffer layer, hole injection layer HIL / hole buffer layer, hole transport layer HTL / hole buffer layer, or hole injection layer HIL / hole transport layer HTL / electron blocking layer EBL stacked from the first electrode EL1, without limitation.

[0061] Hole transport regions (HTRs) can be formed using one or more suitable methods selected from vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) method, inkjet printing, laser printing, and laser-induced thermal imaging (LITI).

[0062] Hole injection layer HIL can include, for example, phthalocyanine compounds (such as copper phthalocyanine), N,N′-diphenyl-N,N′-bis[4-(di-m-tolyl-amino)-phenyl]-biphenyl-4,4′-diamine (DNTPD), 4,4′,4″-[tris(3-methylphenyl)phenylamino]triphenylamine (m-MTDATA), 4,4′,4″-tris(N,N-diphenylamino)triphenylamine (TDATA), 4,4′,4″-tris{N-(2-naphthyl)-N-phenylamino}triphenylamine (2-TNATA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonic acid) (PEDOT / PSS), polyaniline / dodecylbenzenesulfonic acid (PANI / DBSA), polyaniline / camphor sulfonic acid (PANI / CSA), polyaniline / poly(4-styrene sulfonate) (PANI / PSS), N,N′-di(naphthyl-1-yl)-N,N′-diphenyl-benzidine (NPB), triphenylamine-containing polyether ketone (TPAPEK), 4-isopropyl-4′-methyldiphenyliodonium [tetra(pentafluorophenyl)borate] and / or dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexaonitrile (HAT-CN).

[0063] Hole transport layers (HTLs) can include any suitable material, such as carbazole derivatives (e.g., N-phenylcarbazole and / or polyvinylcarbazole), fluorene derivatives, N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1′-biphenyl]-4,4′-diamine (TPD), triphenylamine derivatives (e.g., 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA)), N,N′-bis(naphthyl-1-yl)-N,N′-diphenyl-benzidine (NPB), 4,4′-cyclohexylenebis[N,N-bis(4-methylphenyl)aniline] (TAPC), 3,3′-dimethyl-N4,N4,N4′,N4′-tetram-tolyl-[1,1′-biphenyl]-4,4′-diamine (HMTPD), 1,3-bis(N-carbazolyl)benzene (mCP), etc.

[0064] Electron blocking layers (EBLs) may include, for example, carbazole derivatives (such as N-phenylcarbazole and / or polyvinylcarbazole), fluorene derivatives, N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1′-biphenyl]-4,4′-diamine (TPD), triphenylamine derivatives (such as 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA)), N,N′-bis(naphthyl-1-yl)-N,N′-diphenyl-benzidine (NPB), 4,4′-cyclohexylenebis[N,N-bis(4-methylphenyl)aniline] (TAPC), 4,4′-bis[N,N′-(3-tolyl)amino-3,3′-dimethylbiphenyl] (HMTPD), mCP, etc.

[0065] The thickness of the hole transport region (HTR) can be approximately up to approximately (for example, approximately) up to approximately The thickness of the hole injection layer (HIL) can be, for example, approximately up to approximately The thickness of the hole transport layer (HTL) can be approximately up to approximately For example, the thickness of the electron blocking layer (EBL) can be approximately up to approximately If the thicknesses of the hole transport region HTR, the hole injection layer HIL, the hole transport layer HTL, and the electron blocking layer EBL all independently satisfy their respective ranges mentioned above, then satisfactory (or suitable) hole transport properties can be achieved without significantly increasing the driving voltage.

[0066] In addition to the materials described above, the hole transport region (HTR) may also include a charge-generating material to improve conductivity. The charge-generating material may be uniformly or non-uniformly dispersed in the hole transport region (HTR). The charge-generating material may be, for example, a p-doped agent. The p-doped agent may be one of quinone derivatives, metal oxides, and cyano-containing compounds, without limitation. Non-limiting examples of p-doped agents may include quinone derivatives (such as tetracyanoquinone dimethyl (TCNQ) and / or 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinone dimethyl (F4-TCNQ)) and metal oxides (such as tungsten oxide and / or molybdenum oxide), without limitation.

[0067] As described above, in addition to the hole injection layer (HIL) and the hole transport layer (HTL), the hole transport region (HTR) may also include at least one of a hole buffer layer and an electron blocking layer (EBL). The hole buffer layer can compensate for the optical resonant distance based on the wavelength of light emitted from the emitter layer (EML) and can improve luminous efficiency. Any material that can be included in the hole transport region (HTR) can be used as a material included in the hole buffer layer. The electron blocking layer (EBL) is a layer that prevents or reduces the injection of electrons from the electron transport region (ETR) into the hole transport region (HTR).

[0068] The emitter layer EML is disposed on the hole transmission region HTR. The emitter layer EML can have, for example, approximately up to approximately or approximately up to approximately The thickness of the emitter layer (EML) can be a single layer (e.g., a single-layer structure) formed using a single material (e.g., composed of a single material), a single layer formed using multiple different materials, or a multilayer structure having multiple layers formed using multiple different materials.

[0069] The emitting layer (EML) can emit one of the following colors of light: red, green, blue, white, yellow, and cyan. The EML can include fluorescent or phosphorescent emitting materials.

[0070] In one or more embodiments, the emitting layer EML may be a fluorescent emitting layer. For example, a portion of the light emitted from the emitting layer EML may be thermally activated delayed fluorescence (TADF). For example, the emitting layer EML may include a luminescent component that emits (to emit) thermally activated delayed fluorescence, and in one or more embodiments, the emitting layer EML may be a thermally activated delayed fluorescence emitting layer that emits (to emit) blue light.

[0071] The emitting layer EML of one or more embodiments of the organic electroluminescent device 10 includes a polycyclic compound according to one or more embodiments of the present disclosure.

[0072] In the specification, the term "substituted or unsubstituted" corresponds to an unsubstituted group or a group substituted with at least one substituent selected from the group consisting of deuterium, halogen, cyano, nitro, amino, silyl, oxy, thio, sulfinyl, sulfonyl, carbonyl, boron, phosphonium oxide, phosphonium sulfide, alkyl, alkenyl, alkoxy, cycloalkyl, aryl, and heterocyclic groups. In one or more embodiments, the substituent in each example may be substituted or unsubstituted. For example, biphenyl can be interpreted as aryl or phenyl substituted with a phenyl group.

[0073] In this specification, the term "forming a ring by bonding with an adjacent group" can refer to the formation of a substituted or unsubstituted hydrocarbon ring or a substituted or unsubstituted heterocycle by bonding with an adjacent group. Hydrocarbon rings include aliphatic hydrocarbon rings and aromatic hydrocarbon rings. Heterocycles include aliphatic heterocycles and aromatic heterocycles. The ring formed by bonding with an adjacent group can be a monocyclic or polycyclic ring. In one or more embodiments, the ring formed by bonding with an adjacent group can bond with another ring to form a spirostructure.

[0074] In the specification, the term "adjacent group" can refer to: a pair of substituents in which the first substituent is attached to an atom directly bonded to another atom that is substituted with the second substituent; a pair of substituents attached to the same atom; or a pair of substituents in which the first substituent is located spatially closest to the second substituent. For example, in 1,2-dimethylbenzene, the two methyl groups can be interpreted as "adjacent groups" to each other, and in 1,1-diethylcyclopentane, the two ethyl groups can be interpreted as "adjacent groups" to each other.

[0075] In the specification, examples of halogen atoms may include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0076] In the specification, the alkyl group can be a straight-chain alkyl group, a branched alkyl group, or a cycloalkyl group. The number of carbon atoms in the alkyl group can be from 1 to 50, from 1 to 30, from 1 to 20, from 1 to 10, or from 1 to 6. Examples of alkyl groups may include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, cyclopentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, cyclohexyl, 4-methylcyclohexyl, 4-tert-butylcyclohexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyloctyl, 2-hexyloctyl, 3,7-dimethyloctyl, cyclooctyl, n-nonyl, n-decyl, adamantyl, 2-ethyldecyl, 2-butyldecyl. 2-Hexyldecyl, 2-Octydecyl, undecyl, dodecyl, 2-Ethyldodecyl, 2-Butyldodecyl, 2-Hexyldodecyl, 2-Octydecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, 2-Ethylhexadecyl, 2-Butylhexadecyl, 2-Hexylhexadecyl, 2-Octydecyl, heptadecanyl, octadecyl, nonadecanyl, eicosyl, 2-Ethyleicosyl, 2-Butyleicosyl, 2-Hexyleicosyl, 2-Octydecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecanyl, hexadecyl, octadecyl, nonadecanyl, triadecyl, etc., without limitation.

[0077] In the specification, alkenyl means a hydrocarbon group comprising one or more carbon-carbon double bonds at the middle and / or any end of an alkyl group with two or more carbon atoms. The alkenyl group can be a straight-chain alkenyl or a branched alkenyl. There is no particular limitation on the number of carbon atoms, but it can be 2 to 30, 2 to 20, or 2 to 10. Examples of alkenyl groups include vinyl, 1-butenyl, 1-pentenyl, 1,3-butadienylaryl, styryl, styrylvinyl, etc., without limitation.

[0078] In the specification, alkynyl means a hydrocarbon group comprising one or more carbon-carbon triple bonds at the middle and / or any end of an alkyl group with two or more carbon atoms. The alkynyl group can be straight-chain or branched. There is no particular limitation on the number of carbon atoms, but it can be 2 to 30, 2 to 20, or 2 to 10. Examples of alkynyl groups include ethynyl, propynyl, etc., without limitation.

[0079] In the specification, the hydrocarbon cyclogroup can be an optional functional group or substituent derived from an aliphatic hydrocarbon ring or an optional functional group or substituent derived from an aromatic hydrocarbon ring. The number of carbon atoms in the hydrocarbon cyclogroup for forming the ring can be 5 to 60, 5 to 30, or 5 to 20.

[0080] In the specification, aryl represents an optional functional group or substituent derived from an aromatic hydrocarbon ring. The aryl group can be monocyclic or polycyclic. The number of carbon atoms in the aryl group used to form the ring can be 6 to 30, 6 to 20, or 6 to 15. Examples of aryl groups include phenyl, naphthyl, fluorenyl, anthracene, phenanthryl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, hexaphenyl, benzo[9,10]phenanthryl, pyrene, benzofluoranthracene, etc. Basic, without restrictions.

[0081] In this specification, a heterocyclic group refers to an optional functional group or substituent derived from a ring comprising one or more heteroatoms, including B, O, N, P, Si, and S. Heterocyclic groups include aliphatic heterocyclic groups and aromatic heterocyclic groups. Aromatic heterocyclic groups can be heteroaryl groups. Both aliphatic and aromatic heterocycles can be independently monocyclic or polycyclic.

[0082] In the specification, the heterocyclic group may include one or more of B, O, N, P, Si, and S as heteroatoms. If the heterocyclic group includes two or more heteroatoms, the two or more heteroatoms may be the same or different. The heterocyclic group may be a monocyclic or polycyclic heterocyclic group and has the concept of including heteroaryl groups. The number of carbons in the heterocyclic group for forming the ring may be 2 to 30, 2 to 20, or 2 to 10.

[0083] In the specification, the aliphatic heterocyclic group may include one or more of B, O, N, P, Si, and S as heteroatoms. The number of carbon atoms in the aliphatic heterocyclic group for forming the ring may be 2 to 30, 2 to 20, or 2 to 10. Examples of aliphatic heterocyclic groups may be ethylene oxide, cyclothioalkyl, pyrrolyl, piperidinyl, tetrahydrofuranyl, tetrahydrothiophenyl, thiaalkyl, tetrahydropyranyl, 1,4-dioxane, etc., without limitation.

[0084] In the specification, a heteroaryl group may include one or more of B, O, N, P, Si, and S as heteroatoms. If a heteroaryl group includes two or more heteroatoms, the two or more heteroatoms may be the same or different. The heteroaryl group may be a monocyclic heteroaryl or a polycyclic heteroaryl. The number of carbon atoms in the heteroaryl group for forming the ring may be 2 to 30, 2 to 20, or 2 to 10. Examples of heteroaryl groups may include thienyl, furanyl, pyrrolyl, imidazolyl, triazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, acridineyl, pyridazinyl, quinolinyl, quinazolinyl, quinoxazinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, isoquinolinyl, indolyl, carbazoleyl, N-arylcarbazoleyl, N-heteroarylcarbazoleyl, N-alkylcarbazoleyl, benzoxazolyl, benzimidazolyl, benzothiazolyl, benzocarbazoleyl, benzothiaphenyl, dibenzothiaphenyl, thiaphenothiaphenyl, benzofuranyl, phenanthrololinyl, thiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, thiadiazolyl, phenothiazinyl, dibenzothiaryl, dibenzofuranyl, etc., without limitation.

[0085] In the specification, the amino group may include alkylamino, arylamino, or heteroarylamino. For example, in the amino group, the alkyl, aryl, or heteroaryl groups defined above may be bonded to a nitrogen atom. Examples of amino groups include, but are not limited to, methylamino, dimethylamino, phenylamino, diphenylamino, naphthylamino, 9-methyl-anthraylamino, etc.

[0086] In the specification, the thiol group can include alkyl thio and aryl thio. For example, in the thiol group, the alkyl or aryl group defined above can be bonded to a sulfur atom. Examples of thiol groups include, but are not limited to, methyl thio, ethyl thio, propyl thio, pentyl thio, hexyl thio, octyl thio, dodecyl thio, cyclopentyl thio, cyclohexyl thio, phenyl thio, naphthyl thio, etc.

[0087] In this specification, the boron group includes alkylboron group and arylboron group. For example, in the boron group, the alkyl or aryl group defined above can be bonded to a boron atom. Examples of boron groups include, but are not limited to, dimethylboron, diethylboron, tert-butylmethylboron, diphenylboron, phenylboron, etc.

[0088] In this specification, the oxygen group can include alkyloxy and aryloxy groups. For example, in the oxygen group, the alkyl or aryl group defined above can be bonded to an oxygen atom. Examples of oxygen groups can include methyloxy, ethyloxy, n-propyloxy, isopropyloxy, butyloxy, pentyloxy, hexyloxy, octyloxy, nonyloxy, decyloxy, benzyloxy, etc. However, one or more embodiments of this disclosure are not limited thereto.

[0089] In the specification, "atoms used to form rings" can refer to ring-forming atoms.

[0090] The polycyclic compound according to one or more embodiments of this disclosure is represented by the following formula 1:

[0091] Formula 1

[0092]

[0093] In Equation 1, Y is O or S.

[0094] In Formula 1, rings D through H can each be independently an aryl ring with 6 to 30 cyclic carbon atoms, substituted or unsubstituted, or a heteroaryl ring with 2 to 30 cyclic carbon atoms, substituted or unsubstituted. In one or more embodiments, rings E and F are bonded to each other to form a ring. In one or more embodiments, rings F and H are bonded to each other to form a ring. In one or more embodiments, rings G and E are bonded to each other to form a ring. In one or more embodiments, rings G and Ar are bonded to each other to form a ring. In one or more embodiments, rings D and Ar are bonded to each other to form a ring. Rings E and F, rings F and H, rings G and E, rings G and Ar, and rings D and Ar can each be independently bonded to each other via a straight bond (e.g., a single bond) or a substituent to form a ring.

[0095] In Formula 1, Ar is an aryl group with 6 to 30 cyclic carbon atoms, substituted or unsubstituted, or a heteroaryl group with 2 to 30 cyclic carbon atoms, substituted or unsubstituted.

[0096] In one or more embodiments, Ar in Equation 1 can be represented by the following Equation 2:

[0097] Formula 2

[0098]

[0099] In Formula 2, Ra is a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted thiol group, an substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, an substituted or unsubstituted aryl group with 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 30 cyclic carbon atoms, and optionally, it can be combined with an adjacent group to form a ring.

[0100] In Equation 2, “b” is an integer from 0 to 5. If “b” is an integer of 2 or greater, then the multiple Ra groups are the same or different.

[0101] In one or more embodiments, Equation 1 can be represented by Equation 3 below:

[0102] Formula 3

[0103]

[0104] In Formula 3, R1 to R5 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted thiol group, an substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, an substituted or unsubstituted aryl group with 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 30 cyclic carbon atoms, and optionally, may be combined with adjacent groups to form a ring.

[0105] In Equation 3, “e” is an integer from 0 to 4, where if “e” is an integer of 2 or greater, then the multiple R1 groups are the same or different.

[0106] In Equation 3, “f” is an integer from 0 to 4, where if “f” is an integer of 2 or greater, then the multiple R2 groups are the same or different.

[0107] In Equation 3, “g” is an integer from 0 to 4, where if “g” is an integer of 2 or greater, then multiple R4 groups are the same or different.

[0108] In Equation 3, "h" is an integer from 0 to 4, where if "h" is an integer of 2 or greater, then multiple R5 groups are the same or different.

[0109] In Equation 3, Y and Ar are the same as those defined in Equation 1.

[0110] In one or more embodiments, R1 to R5 of Formula 3 may each be independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted arylamine group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophene group.

[0111] In one or more embodiments, at least one of R1 to R5 may be a substituted or unsubstituted amino group or a substituted or unsubstituted N-containing heteroaryl group.

[0112] In one or more embodiments, equation 3 can be represented by equation 4-1 or equation 4-2 below:

[0113] Equation 4-1

[0114]

[0115] Equation 4-2

[0116]

[0117] In Formulas 4-1 and 4-2, Ra is a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted thiol group, a substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, a substituted or unsubstituted aryl group with 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 30 cyclic carbon atoms, and optionally, it can be combined with an adjacent group to form a ring.

[0118] In Equations 4-1 and 4-2, “b” is an integer from 0 to 5, where if “b” is an integer of 2 or greater, the multiple Ra groups are the same or different.

[0119] In Equations 4-1 and 4-2, "e′" and "f′" are both independent integers from 0 to 3. If "e′" is an integer of 2 or greater, then the multiple R1 groups are the same or different, and if "f′" is an integer of 2 or greater, then the multiple R2 groups are the same or different.

[0120] In Equations 4-1 and 4-2, Y, R1 to R5, and “e” to “h” are the same as those defined in Equation 3.

[0121] In one or more embodiments, equation 4-1 can be represented by equation 5-1 or equation 5-2 below:

[0122] Formula 5-1

[0123]

[0124] Formula 5-2

[0125]

[0126] In Formulas 5-1 and 5-2, R4′ and R5′ can each be independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted arylamine group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophene group.

[0127] In Formulas 5-1 and 5-2, both “g′” and “h′” are independent integers from 0 to 3. If “g′” is an integer of 2 or greater, then the multiple R4 groups are the same or different, and if “h′” is an integer of 2 or greater, then the multiple R5 groups are the same or different.

[0128] In Equations 5-1 and 5-2, Y, R1 to R5, Ra, “b” and “e” to “h” are the same as those defined in Equation 4-1.

[0129] In one or more embodiments, Y in Equations 1 and 3 to 5-2 can be O.

[0130] In one or more embodiments, the polycyclic compound represented by Formula 1 may be at least one of the compounds represented in Group 1 of the following compounds, but one or more embodiments of this disclosure are not limited thereto:

[0131] Compound group 1

[0132]

[0133]

[0134]

[0135] Polycyclic compounds can be used in one or more embodiments of the organic electroluminescent device 10 to improve the efficiency and lifetime of the organic electroluminescent device 10. For example, polycyclic compounds can be used in the emission layer EML of one or more embodiments of the organic electroluminescent device 10 to improve the emission efficiency and lifetime of the organic electroluminescent device 10.

[0136] In one or more embodiments, the emission layer EML may be a delayed fluorescence emission layer comprising a first compound and a second compound, and the polycyclic compound of one or more embodiments represented by Formula 1 may be included in the first compound of the emission layer EML. For example, the first compound may be a dopant and the second compound may be the host compound.

[0137] In one or more embodiments, the host may be a host for emitting (e.g., to emit) delayed fluorescence, and the dopant may be a dopant for emitting (e.g., to emit) delayed fluorescence. In one or more embodiments, a polycyclic compound represented by Formula 1 may be included as a dopant material for the emission layer EML. For example, a polycyclic compound represented by one or more embodiments of Formula 1 may be used as a TADF dopant.

[0138] In one or more embodiments, the organic electroluminescent device 10 may include a plurality of emitting layers. The plurality of emitting layers may be stacked one after another. For example, the organic electroluminescent device 10 including multiple emitting layers may emit white light. The organic electroluminescent device 10 including multiple emitting layers may be an organic electroluminescent device having a tandem structure. If the organic electroluminescent device 10 includes multiple emitting layers, at least one emitting layer may include a polycyclic compound according to the present disclosure as described above.

[0139] The emitter layer (EML) may also include dopant materials, and any suitable material can be used as the dopant. For example, styrene derivatives (e.g., 1,4-bis[2-(3-N-ethylcarbazolyl)vinyl]benzene (BCzVB), 4-(di-p-tolylamino)-4′-[(di-p-tolylamino)styrene]stilbene (DPAVB) and / or N-(4-((E)-2-(6-((E)-4-(diphenylamino)styrene)naphth-2-yl)vinyl)phenyl)-N-phenylbenzene) The following are permitted, without limitation: amines (N-BDAVBi), perylene and its derivatives (e.g., 2,5,8,11-tetra-tert-butylperylene (TBP)), pyrene and its derivatives (e.g., 1,1′-dipyrene, 1,4-dipyrenebenzene, 1,4-bis(N,N-diphenylamino)pyrene, 1,6-bis(N,N-diphenylamino)pyrene and / or 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi)).

[0140] The emitter layer EML can also include any suitable material as the host material. For example, the emitter layer EML can include tris(8-hydroxyquinoline)aluminum (Alq3), bis[2-(diphenylphosphino)phenyl]ether oxide (DPEPO), 4,4′-bis(N-carbazole-9-yl)biphenyl (CBP), 1,3-bis(carbazole-9-yl)benzene (mCP), 2,8-bis(diphenylphosphino)dibenzo[b,d]furan (PPF), 4,4′,4″-tris(carbazole-9-yl)triphenylamine (TCTA), poly(N-vinylcarbazole) (PVK), 9,10-bis(naphthyl-2-yl)anthracene (ADN), 2-tert-butyl-9,10-bis(naphthyl-2-yl)anthracene, etc. The main material may be at least one of the following: 4,4′-bis(9-carbazolyl)-2,2′-dimethylbiphenyl (CDBP), 2-methyl-9,10-bis(naphthyl-2-yl)anthracene (MADN), hexaphenylcyclotriphosphazene (CP1), 1,4-bis(triphenylsilyl)benzene (UGH-2), hexaphenylcyclotrisiloxane (DPSiO3), octaphenylcyclotetrasiloxane (DPSiO4), and 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi), without limitation.

[0141] When the emitting layer EML emits red light, the emitting layer EML may further include, for example, fluorescent materials including tris(dibenzoylmethane)phenanthroline europium (PBD: Eu(DBM)3(Phen)) and / or pyrene. When the emitting layer EML emits red light, the dopants included in the emitting layer EML may be selected from, for example, organometallic complexes (such as bis(1-phenylisoquinoline)acetylacetonate iridium (PIQIr(acac)), bis(1-phenylquinoline)acetylacetonate iridium (PQIr(acac)), tris(1-phenylquinoline)iridium (PQIr) and / or octaethylporphyrin platinum (PtOEP)), rubrene and its derivatives, and 4-dicyanomethylene-2-(p-dimethylaminostyryl)-6-methyl-4H-pyran (DCM) and its derivatives.

[0142] When the emitting layer EML emits green light, the emitting layer EML may also include a fluorescent material, for example, tris(8-hydroxyquinoline)aluminum (Alq3). When the emitting layer EML emits green light, the dopants included in the emitting layer EML may be selected from, for example, organometallic complexes (such as planar-tris(2-phenylpyridine)iridium (Ir(ppy)3)) and coumarins and their derivatives.

[0143] When the emitting layer EML emits blue light, the emitting layer EML may further include a fluorescent material selected from at least one of the groups consisting of spiro-DPVBi, spiro-6P, stilbene (DSB), stilbene-arylide (DSA), polyfluorene (PFO) polymers, and poly(p-phenylenevinylene) (PPV) polymers. When the emitting layer EML emits blue light, the dopant included in the emitting layer EML may be selected from, for example, organometallic complexes (such as (4,6-F₂ppy)₂Irpic) and perylene and its derivatives.

[0144] In one or more embodiments of the organic electroluminescent device 10, such as Figures 1 to 4 As shown, the electron transport region (ETR) is disposed on the emitter layer (EML). The electron transport region (ETR) may include at least one of the hole blocking layer (HBL), the electron transport layer (ETL), and the electron injection layer (EIL). However, one or more embodiments of this disclosure are not limited thereto.

[0145] The electronic transport region (ETR) can have a single layer (e.g., a single-layer structure) formed using a single material (e.g., composed of a single material), a single layer formed using multiple different materials, or a multilayer structure having multiple layers formed using multiple different materials.

[0146] For example, the electron transport region (ETR) can have a single-layer structure of an electron injection layer (EIL) or an electron transport layer (ETL), or a single-layer structure formed using an electron injection material and an electron transport material. In some embodiments, the ETR can have a single-layer structure comprising a variety of different materials, or a structure of an electron transport layer (ETL) / electron injection layer (EIL) or a hole blocking layer (HBL) / electron transport layer (ETL) / electron injection layer (EIL) stacked from the emitter layer (EML), without limitation. The thickness of the ETR can be, for example, approximately up to approximately

[0147] The electron transport region (ETR) can be formed using one or more suitable methods selected from vacuum deposition, spin coating, casting, Langmuir-Blodget (LB) method, inkjet printing, laser printing, and laser-induced thermal imaging (LITI).

[0148] If the electron transport region (ETR) includes an electron transport layer (ETL), then the ETL may include anthracene compounds. The ETL may include, for example, tris(8-hydroxyquinoline)aluminum (Alq3), 1,3,5-tris[(3-pyridyl)-benzene-3-yl]benzene, 2,4,6-tris(3′-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine, bis[2-(diphenylphosphino)phenyl]ether oxide (DPEPO), 2-(4-(N-phenylbenzimidazol-1-yl)phenyl)-9,10-dinaphthylanthracene, 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1, 10-Phenanthroline (Bphen), 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), 4-(naphthyl-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (tBu-PBD), bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1′-biphenyl-4-hydroxy)aluminum (BAlq), bis(benzoquinoline-10-hydroxy)beryllium (Bebq2), 9,10-bis(naphthyl-2-yl)anthracene (ADN), or mixtures thereof, without limitation. The thickness of the electron transport layer (ETL) can be approximately up to approximately And it can be, for example, about up to approximately If the thickness of the electron transport layer (ETL) meets the above range, satisfactory (or suitable) electron transport properties can be obtained without significantly increasing the driving voltage.

[0149] If the electron transport region (ETR) includes an electron injection layer (EIL), the EIL may comprise a metal halide (such as LiF, NaCl, CsF, RbCl, and / or RbI), a lanthanide (such as Yb), a metal oxide (such as Li₂O and / or BaO), and / or lithium 8-hydroxyquinoline (LiQ). However, one or more embodiments of this disclosure are not limited thereto. The EIL may also be formed using a mixture of an electron injection material and an insulating organometallic salt. The organometallic salt may be a material having a band gap of approximately 4 eV or greater. For example, the organometallic salt may be selected from metal acetates, metal benzoates, metal acetoacetates, metal acetylacetonates, and metal stearates. The thickness of the EIL may be approximately up to approximately For example, approximately up to approximately If the thickness of the electron injection layer (EIL) meets the above range, satisfactory (or suitable) electron injection characteristics can be obtained without significantly increasing the driving voltage.

[0150] The electron transport region (ETR) may include a hole blocking layer (HBL) as described above. The hole blocking layer (HBL) may include at least one of, for example, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), bis[2-(diphenylphosphino)phenyl]ether oxide (DPEPO), and 4,7-diphenyl-1,10-phenanthroline (Bphen). However, one or more embodiments of this disclosure are not limited thereto.

[0151] The second electrode EL2 is disposed on the electron transport region ETR. The second electrode EL2 can be a common electrode and / or a cathode. The second electrode EL2 can be a transmission electrode, a transmission-reflection electrode, or a reflection electrode. If the second electrode EL2 is a transmission electrode, it can include a transparent metal oxide, such as ITO, IZO, ZnO, ITZO, etc.

[0152] If the second electrode EL2 is a transmissive or reflective electrode, then the second electrode EL2 may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, Yb, In, Sn, Zn, compounds thereof, mixtures thereof (e.g., AgMg, LiF / Ca, LiF / Al, AgYb and / or MgAg) and / or oxides thereof. In one or more embodiments, the second electrode EL2 may have a multilayer structure, which includes a reflective or transmissive layer formed using any of the above-described materials and a transparent conductive layer formed using ITO, IZO, ZnO, ITZO, etc.

[0153] In one or more embodiments, the second electrode EL2 may be connected to an auxiliary electrode. When the second electrode EL2 is connected to the auxiliary electrode, the resistance of the second electrode EL2 can be reduced.

[0154] Reference Figure 4 In one or more embodiments of the organic electroluminescent device 10, a capping layer CPL may be further included on the second electrode EL2. The capping layer CPL may have a single-layer structure or a multi-layer structure.

[0155] In one or more embodiments, the capping CPL can be an organic layer or an inorganic layer. For example, if the capping CPL comprises an inorganic material, the inorganic material may include alkali metal compounds (such as LiF), alkaline earth metal compounds (such as MgF2), SiON, SiN. x and / or SiO y wait.

[0156] For example, if the capping CPL comprises an organic material, the organic material may include α-NPD, NPB, TPD, m-MTDATA, Alq3, CuPc, N4,N4,N4′,N4′-tetra(biphenyl-4-yl)biphenyl-4,4′-diamine (TPD15), 4,4′,4″-tris(carbazole-9-yl)triphenylamine (TCTA), epoxy resins, and / or acrylate resins (such as methacrylate resins). However, one or more embodiments of this disclosure are not limited thereto, and the capping CPL may comprise an amine compound. For example, the capping CPL may comprise at least one of the following compounds P1 to P5:

[0157]

[0158]

[0159] The refractive index (refractive index) of the capping CPL can be 1.6 or greater. For example, the refractive index of the capping CPL can be 1.6 or greater relative to light with wavelengths ranging from approximately 550 nm to approximately 660 nm.

[0160] In the organic electroluminescent device 10, when voltages are applied to the first electrode EL1 and the second electrode EL2, holes injected from the first electrode EL1 move to the emitter layer EML through the hole transport region HTR, and electrons injected from the second electrode EL2 move to the emitter layer EML through the electron transport region ETR. Electrons and holes recombine in the emitter layer EML to generate excitons, and light is emitted by transitioning from the excited state to the ground state via the excitons.

[0161] If the organic electroluminescent device 10 is a top-emitting device, then the first electrode EL1 can be a reflective electrode, and the second electrode EL2 can be a transmissive electrode or a transmissive-reflective electrode. If the organic electroluminescent device 10 is a bottom-emitting device, then the first electrode EL1 can be a transmissive electrode or a transmissive-reflective electrode, and the second electrode EL2 can be a reflective electrode.

[0162] The organic electroluminescent device 10 according to one or more embodiments of the present disclosure is characterized by comprising a polycyclic compound represented by Formula 1 and exhibiting high efficiency and long lifetime. In one or more embodiments, the organic electroluminescent device 10 of one or more embodiments can exhibit high efficiency and long lifetime characteristics in the deep blue wavelength region.

[0163] In the following text, this disclosure will be specifically explained with reference to embodiments and comparative embodiments. The following embodiments are merely illustrative examples to help understand this disclosure, and the scope of this disclosure is not limited thereto.

[0164] Example

[0165] Synthesis of polycyclic compounds

[0166] The methods for synthesizing polycyclic compounds described below are merely examples, and the methods for synthesizing polycyclic compounds according to one or more embodiments of this disclosure are not limited thereto.

[0167] 1. Synthesis of Compound 1

[0168] (1) Synthesis of compound A-1

[0169]

[0170] 1,3-Dibromo-5-methoxybenzene (25.0 g, 94.0 mmol), diphenylamine (35.0 g, 206.8 mmol), Pd(dba)2 (2.7 g, 4.7 mmol), P(tBu)3HBF4 (1.6 g, 5.6 mmol), tBuONa (31.6 g, 329.0 mmol), and toluene (376 mL) were refluxed under an Ar atmosphere and stirred for approximately 4 hours. The reaction products were separated by silica gel column chromatography and washed with hexane to obtain 32.8 g (yield: 79%) of a white solid. The obtained compound was determined by rapid atomic impact mass spectrometry (FAB-MS), confirming a molecular weight of 442 and identifying the target compound A-1.

[0171] (2) Synthesis of compound A-2

[0172]

[0173] Compound A-1 (25 g, 56.5 mmol) and 300 mL of DCM (dichloromethane) were placed in a reaction vessel, and a small amount of BBr3 (28.3 g, 113.0 mmol) was added while stirring at approximately -78 °C. After the complete addition of BBr3, the temperature was raised to room temperature and stirred at room temperature for approximately 24 hours. After separating the reaction mixture by silica gel column chromatography, the reaction product was washed with DCM and AcOEt to obtain 13.9 g (yield: 57%) of a white solid. The molecular weight of the obtained compound was confirmed by FAB-MS, confirming it as 428, and the target compound A-2 was identified.

[0174] (3) Synthesis of compound A-3

[0175]

[0176] Compound A-2 (15 g, 35.0 mmol), iodobenzene (21.4 g, 105.0 mmol), K₂CO₃ (32.3 g, 234.0 mmol), CuI (0.333 g, 1.7 mmol), Fe(III)(acac)₃ (1.24 g, 3.5 mmol), and 700 mL of NMP were stirred at approximately 180 °C for approximately 9 hours under an Ar atmosphere. The reaction product was separated by silica gel column chromatography to obtain 3.62 g (yield: 21%) of a yellowish-white solid. The molecular weight of the obtained compound was confirmed as 504 by FAB-MS, and the target compound A-3 was identified.

[0177] (4) Synthesis of Compound 1

[0178]

[0179] Compounds A-3 (3.6 g, 7.13 mmol), BI3 (14.0 g, 35.7 mmol), BPh3 (3.45 g, 14.3 mmol), and 143 mL of 1,2,4-trichlorobenzene were stirred at approximately 180 °C for about 6 hours under an Ar atmosphere. The temperature was then lowered to approximately 120 °C, and N,N-diisopropylethylamine (18.4 mL, 107.0 mmol) was added, followed by stirring for approximately 30 minutes. The crude product obtained was separated by silica gel column chromatography to give 0.557 g (yield: 15%) of a yellow solid. The molecular weight of the obtained compound was confirmed as 520 by FAB-MS, confirming the target compound 1.

[0180] 2. Synthesis of Compound 23

[0181] (1) Synthesis of compound B-2

[0182]

[0183] Compound B-2 was synthesized using essentially the same method as that used for compound A-3, except that compound B-1 was used instead of compound A-2 and 1,3-dibromobenzene was used instead of iodobenzene. The target material was obtained in a 19% yield. The molecular weight of the resulting compound was confirmed as 639 by FAB-MS measurement, thus confirming the target compound B-2.

[0184] (2) Synthesis of compound B-3

[0185]

[0186] Compound B-3 was synthesized using essentially the same method as that used for compound 1, except that compound B-2 was used instead of compound A-3. The target material was obtained in a 15% yield. The molecular weight of the resulting compound was confirmed as 655 by FAB-MS measurement, thus confirming the target compound B-3.

[0187] (3) Synthesis of compound 23

[0188]

[0189] Compound B-3 (10.0 g, 15.3 mmol), diphenylamine (DPA) (2.58 g, 15.3 mmol), tBuONa (1.54 g, 16.0 mmol), Pd(dba)2 (0.439 g, 0.760 mmol), Sphos (0.376 g, 0.920 mmol), and 153 mL of toluene were placed in a reaction vessel and refluxed under an Ar atmosphere for approximately 4 hours. The crude product obtained was separated by silica gel column chromatography to give 7.66 g (yield: 68%) of a yellow solid. The molecular weight of the obtained compound was confirmed by FAB-MS, and the target compound 23 was identified.

[0190] 3. Synthesis of Compound 24

[0191]

[0192] Compound 24 was synthesized using essentially the same method as compound 23, except that carbazole was used instead of DPA. The target material was obtained (yield: 43%). The molecular weight of the obtained compound was confirmed as 741 by FAB-MS measurement, thus confirming the target compound 24.

[0193] 4. Synthesis of Compound 3

[0194] (1) Synthesis of compound D-1

[0195]

[0196] Compound D-1 was synthesized using essentially the same method as compound A-1, except that carbazole was used instead of DPA and tert-butylbenzene was used instead of toluene. The reaction was carried out at approximately 150 °C, and the target material was obtained in a yield of 39%. The molecular weight of the obtained compound was confirmed to be 352 by FAB-MS measurement, thus confirming the target compound D-1.

[0197] (2) Synthesis of compound D-2

[0198]

[0199] Compound D-1 (25.0 g, 71.0 mmol), diphenylamine (13.2 g, 78.1 mmol), Pd(dba)2 (1.0 g, 1.8 mmol), P(tBu)3HBF4 (0.6 g, 2.1 mmol), tBuONa (11.9 g, 124.2 mmol), and toluene (284 mL) were refluxed under an Ar atmosphere and stirred for approximately 4 hours. The crude product was separated by silica gel column chromatography and washed with hexane to obtain 23.5 g (yield: 75%) of a white solid. The molecular weight of the obtained compound was confirmed by FAB-MS, confirming it as 440, and the target compound D-2 was identified.

[0200] (3) Synthesis of compound 3

[0201]

[0202] Compounds D-3, D-4, and 3 were synthesized using essentially the same method as that used to synthesize compounds A-2, A-3, and 1, respectively, yielding the resulting yellow solids. The molecular weights of the obtained compounds were confirmed to be 518 by FAB-MS measurement, and the target compound 3 was identified.

[0203] 5. Synthesis of Compound 16

[0204] (1) Synthesis of compound E-2

[0205]

[0206] Except that compound E-1 was used instead of compound A-3, compound E-2 was synthesized in 16% yield using essentially the same method as that used to synthesize compound 1. The molecular weight of the resulting compound was confirmed as 678 by FAB-MS measurement, thus confirming the target compound E-2.

[0207] (2) Synthesis of compound 16

[0208]

[0209] Except for doubling the amount of DPA used in the synthesis of compound 23, compound 16 was synthesized using essentially the same method as that used to synthesize compound 23, and the target material was obtained in a yield of 52%. The resulting compound was confirmed to have a molecular weight of 854 by FAB-MS measurement, thus confirming the target compound 16.

[0210] Manufacturing of organic electroluminescent devices

[0211] The above-described compounds were used as materials for each emission layer to fabricate organic electroluminescent devices of Examples 1 to 5.

[0212] Example compounds

[0213]

[0214] Organic electroluminescent devices of Comparative Examples 1 to 3 were fabricated using comparative compounds X-1 to X-3 as materials for each emission layer.

[0215] Comparative compounds

[0216]

[0217] The organic electroluminescent devices in both the example and comparative examples are fabricated using the following methods.

[0218] On a glass substrate, a thickness of approximately The ITO was patterned, washed with ultrapure water, and treated with UV ozone for approximately 10 minutes. Then, HAT-CN was deposited to approximately... The thickness of α-NPD was deposited to approximately [a certain thickness]. And deposit mCP to approximately The thickness is increased to form a hole transport region.

[0219] Then, the example compound or comparative compound and mCP are co-deposited at a weight ratio of 1:99 to form a thickness of approximately The layers are used to form the emission layer.

[0220] On the emitter layer, a thickness of approximately [thickness missing] is formed using DPEPO. The layer, formed using TPBi, has a thickness of approximately The layer, and formed using LiF with a thickness of approximately A layer is formed to create an electron transport region. Then, aluminum (Al) is used to form a layer with a thickness of approximately... The second electrode was then used. Compound P4 was then deposited to a thickness of approximately 70 nm to form a capping layer. All layers were formed using a vacuum deposition apparatus.

[0221] Property evaluation of compounds

[0222] For both example and comparative compounds, emission spectra were measured at room temperature and 77 K using a JASCO V-670 spectrometer with 5.0 mM toluene solutions as control. The maximum emission wavelength (λmax) and full width at half maximum (FWHM) of the emission spectra at room temperature were evaluated. Additionally, the triplet energy level (T1) was calculated based on the initial values ​​of the emission spectra at 77 K.

[0223] Table 1

[0224]

[0225]

[0226] Evaluation of the properties of organic electroluminescent devices

[0227] To evaluate the properties of the organic electroluminescent devices according to the example and comparative examples, measurements were taken at 1,000 cd / m². 2 The maximum emission wavelength (nm), maximum external quantum efficiency (%), and external quantum efficiency (%) at the specified brightness were measured using a C9920-11 brightness distribution characteristic measurement system from Hamamatsu Photonics Co.

[0228] Table 2

[0229]

[0230] Referring to the results in Table 1, it can be confirmed that the polycyclic compounds according to one or more embodiments achieve a reduction in wavelength, a reduction in full width at half maximum (FWHM), and an increase in triplet energy levels. Referring to the results in Table 2, it can be confirmed that, compared with the comparative example, the organic electroluminescent device comprising the polycyclic compound according to one or more embodiments in the emitter layer exhibits an improved maximum external quantum efficiency (EQE). max ) and external quantum efficiency (EQE) 1000nit Additionally, it can be confirmed that the blue color of the emission can be deepened.

[0231] The polycyclic compounds according to one or more embodiments include cross-linked structures having chalcogenide elements (e.g., oxygen) as cross-linking agents and cross-linked structures having nitrogen as cross-linking agents, and can induce spatial distortion of the molecule. Therefore, in the polycyclic compounds according to one or more embodiments, due to the suppression (e.g., restriction) of intramolecular conjugation, a reduction in wavelength and an increase in triplet energy levels can be achieved, and reverse intersystem crossing can be promoted. Furthermore, because the polycyclic compounds according to one or more embodiments include cross-linked structures with chalcogenide elements, narrow emission spectra can be achieved without affecting the full width at half maximum (FWHM) of the emission spectrum, thus enabling organic electroluminescent devices that emit deep blue light with high efficiency and high color purity.

[0232] In contrast, compound X-1 in Comparative Example 1 comprises a bulky mesitylgroup bound to boron and has a standing structure relative to the parent skeleton, resulting in low intramolecular planarity. Unbound by any particular theory, it is assumed that the excited state exhibits high structural relaxation, leading to an increased full width at half maximum (FWHM) and a deterioration in emission efficiency.

[0233] In contrast, compound X-2 of Example 2 has a cross-linked structure relative to the parent skeleton and becomes a molecule with very high planarity, thus achieving a narrow full width at half maximum (FWHM) similar to the example. However, the structure of compound X-2 is not a cross-linked structure of chalcogens (e.g., compound X-2 does not have chalcogens as cross-linking agents), but rather a single-bond cross-linked structure, and the high planarity leads to molecular aggregation, which may result in an increase in wavelength and a deterioration in emission efficiency at high brightness.

[0234] In contrast, compound X-3 of Comparative Example 3 does not include a cross-linked structure of chalcogenide elements, but rather a cross-linked structure of aromatic amines (e.g., compound X-3 has an aromatic amine as a cross-linking agent). It was confirmed that compound X-3 induces intramolecular twisting through the cross-linked structure of the aromatic amine, and achieves a relative reduction in wavelength compared to compounds X-1 and X-2. However, due to the excited-state structural relaxation of the aryl group in the aromatic amine, compound X-3 is expected to have an increased full width at half maximum (FWHM) and result in a deterioration in device efficiency.

[0235] One or more embodiments of the organic electroluminescent device use a polycyclic compound represented by Formula 1 as the material of the emission layer and can achieve high emission efficiency in the blue light wavelength region.

[0236] One or more embodiments of the polycyclic compound are used as materials for the emission layer, and high emission efficiency of organic electroluminescent devices can be achieved in the blue light wavelength region.

[0237] Organic electroluminescent devices according to one or more embodiments of this disclosure can achieve high efficiency and long lifespan.

[0238] The polycyclic compounds according to one or more embodiments of this disclosure can improve the lifetime and efficiency of organic electroluminescent devices.

[0239] As used in this article, the term “use” and its variants can be considered synonymous with the term “utilize” and its variants, respectively.

[0240] Furthermore, the terms “basic,” “approximately,” and similar terms are used as approximate terms rather than terms of degree, and are intended to take into account the inherent biases of the measured or calculated values ​​that would be recognized by a person skilled in the art.

[0241] Furthermore, any numerical range stated herein is intended to include all subranges with the same numerical precision contained within the stated range. For example, the range “1.0 to 10.0” is intended to include all subranges between the stated minimum value of 1.0 and the stated maximum value of 10.0 (and including both the stated minimum value of 1.0 and the stated maximum value of 10.0), i.e., a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as 2.4 to 7.6. Any maximum numerical limit stated herein is intended to include all lower numerical limits contained therein, and any minimum numerical limit stated in this specification is intended to include all higher numerical limits contained therein. Therefore, the applicant reserves the right to amend this specification (including the claims) to expressly state any subranges contained within the expressly stated range herein.

[0242] Although exemplary embodiments of this disclosure have been described, it is understood that this disclosure should not be limited to these exemplary embodiments, but rather that various changes and modifications can be made by those skilled in the art within the spirit and scope of this disclosure as claimed by the claims and their equivalents.

Claims

1. An organic electroluminescent device, the organic electroluminescent device comprising: First electrode; The hole transport region is located on the first electrode; The emission layer is located on the hole transport region; The electron transmission region is located on the emission layer; as well as The second electrode is located on the electron transport region. Wherein, both the first electrode and the second electrode independently comprise at least one selected from Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, In, Sn, Zn, two or more compounds selected from them, mixtures thereof, and oxides thereof, and The emission layer comprises a polycyclic compound represented by Formula 1: Formula 1 In Equation 1, Y is either O or S. Rings D through H are all independently substituted or unsubstituted benzene rings, and optionally, rings E and F, F and H, G and E, or G and Ar are bonded to each other to form a ring. Ar is expressed by Equation 2: Formula 2 In this case, the substituents on the benzene ring are independently hydrogen atoms, deuterium atoms, halogen atoms, nitro groups, cyano groups, hydroxyl groups, alkyl groups with 1 to 20 carbon atoms, substituted or unsubstituted phenylamino groups, substituted or unsubstituted phenyl groups, substituted or unsubstituted carbazole groups, substituted or unsubstituted dibenzofuran groups, or substituted or unsubstituted dibenzothiophene groups. In Equation 2, Ra can be a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, an alkyl group with 1 to 20 carbon atoms, or a substituted or unsubstituted phenyl group. "b" is an integer from 0 to 5, and In this context, "substitution" means the substitution of at least one of an alkyl group having a deuterium atom, or an alkyl group having 1 to 20 carbon atoms, or a phenyl group.

2. The organic electroluminescent device according to claim 1, wherein, Equation 1 is expressed by Equation 3: Formula 3 In Equation 3, R1 through R5 are each independently a hydrogen atom, a deuterium atom, an alkyl group with 1 to 20 carbon atoms, a substituted or unsubstituted phenylamino group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted carbazole group, a substituted or unsubstituted dibenzofuran group, or a substituted or unsubstituted dibenzothiophene group, and optionally, are combined with adjacent groups to form a ring. "e" through "h" are all independent integers from 0 to 4, and Y and Ar are the same as those defined in Equation 1.

3. The organic electroluminescent device according to claim 2, wherein, R1 to R5 are each independently a hydrogen atom, a deuterium atom, an alkyl group with 1 to 20 carbon atoms, an unsubstituted phenylamino group, an unsubstituted phenyl group, an unsubstituted carbazolyl group, an unsubstituted dibenzofuranyl group, or an unsubstituted dibenzothiophene group.

4. The organic electroluminescent device according to claim 1, further comprising a capping layer located on the second electrode, the capping layer having a refractive index of 1.6 or greater.

5. The organic electroluminescent device according to claim 2, wherein, At least one of R1 to R5 includes a substituted or unsubstituted phenylamino group, a substituted or unsubstituted carbazole group, a substituted or unsubstituted dibenzofuran group, or a substituted or unsubstituted dibenzothiophene group.

6. The organic electroluminescent device according to claim 2, wherein, Equation 3 is expressed by Equation 4-1 or Equation 4-2: Equation 4-1 Equation 4-2 Among them, in equations 4-1 and 4-2, Ra is a hydrogen atom, a deuterium atom, an alkyl group with 1 to 20 carbon atoms, or a substituted or unsubstituted phenyl group, and optionally, it is combined with an adjacent group to form a ring. Both "e′" and "f′" are independent integers from 0 to 3, and "b", Y, R1 to R5 and "e" to "h" are the same as those defined in Equation 3.

7. The organic electroluminescent device according to claim 6, wherein, Equation 4-1 is expressed by Equation 5-1 or Equation 5-2: Formula 5-1 Formula 5-2 Among them, in equations 5-1 and 5-2, R4′ and R5′ are both independently hydrogen atoms, deuterium atoms, unsubstituted phenylamino groups, unsubstituted phenyl groups, unsubstituted carbazole groups, unsubstituted dibenzofuran groups, or unsubstituted dibenzothiophene groups. Both "g′" and "h′" are independent integers from 0 to 3, and Y, R1 to R5, Ra, "b" and "e" to "h" are the same as those defined in Equation 4-1.

8. The organic electroluminescent device according to claim 1, wherein, The polycyclic compound represented by Formula 1 is at least one of the compounds represented in Compound Group 1: Compound group 1 9. A polycyclic compound, said polycyclic compound being represented by Formula 1: Formula 1 in, In Equation 1, Y is either O or S. Rings D through H are all independently substituted or unsubstituted benzene rings, and optionally, rings E and F, F and H, G and E, or G and Ar are bonded to each other to form a ring. Ar is expressed by Equation 2: Formula 2 In this case, the substituents on the benzene ring are independently hydrogen atoms, deuterium atoms, halogen atoms, nitro groups, cyano groups, hydroxyl groups, alkyl groups with 1 to 20 carbon atoms, substituted or unsubstituted phenylamino groups, substituted or unsubstituted phenyl groups, substituted or unsubstituted carbazole groups, substituted or unsubstituted dibenzofuran groups, or substituted or unsubstituted dibenzothiophene groups. In Equation 2, Ra can be a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, an alkyl group with 1 to 20 carbon atoms, or a substituted or unsubstituted phenyl group. "b" is an integer from 0 to 5, and In this context, "substitution" means the substitution of at least one of an alkyl group having a deuterium atom, or an alkyl group having 1 to 20 carbon atoms, or a phenyl group.

10. A polycyclic compound, said polycyclic compound being compound 15:

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