Light emitting diode

Abstract

Provided is a light emitting diode including a first electrode, a second electrode disposed on the first electrode, and an emission layer disposed between the first electrode and the second electrode and including a polycyclic compound represented by Formula 1, thereby exhibiting high luminous efficiency and improved lifespan characteristics, [Formula 1] wherein, in Formula 1, X1 to X4, a to d, R1 to R4, and L are each the same as defined in the specification.

Description

[0001] This application claims priority and benefit to Korean Patent Application No. 10-2021-0044667, filed on April 6, 2021, with the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The disclosure herein relates to a light-emitting diode comprising a novel polycyclic compound in its emitting layer. Background Technology

[0003] We continue to actively develop organic electroluminescent display devices and the like as image display devices. Organic electroluminescent display devices are display devices that include so-called self-emissive light-emitting diodes (LEDs). In a self-emissive light-emitting diode, holes and electrons injected from the first electrode and the second electrode recombine in the emitting layer, causing the light-emitting material in the emitting layer to emit light to achieve display.

[0004] When applying light-emitting diodes (LEDs) to display devices, LEDs with low driving voltage, high luminous efficiency, and long lifespan are required, and materials for LEDs that can reliably achieve these characteristics need to be continuously developed.

[0005] In recent years, in order to achieve high-efficiency light-emitting diodes, technologies involving phosphorescence emission using triplet energy or delayed fluorescence using triplet-triplet annihilation (TTA) in which singlet excitons are generated through collisions of triplet excitons are also being developed, and thermally activated delayed fluorescence (TADF) materials using the delayed fluorescence phenomenon are being developed.

[0006] It will be understood that the background art in the technical section is partly intended to provide useful background information for understanding the technology. However, the background art in the technical section may also include ideas, concepts, or knowledge that were not known or understood by one of skill in the art prior to the corresponding valid date of submission of the subject matter disclosed herein. Summary of the Invention

[0007] The present invention discloses a light-emitting diode exhibiting excellent luminous efficiency and long lifespan characteristics.

[0008] An embodiment provides a light-emitting diode (LED), which may include: a first electrode; a second electrode disposed on the first electrode; and an emitting layer disposed between the first electrode and the second electrode. The first electrode and the second electrode may each independently comprise Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, In, Sn, Zn, their oxides, their compounds, or mixtures thereof, and the emitting layer may comprise a polycyclic compound represented by Formula 1.

[0009] [Formula 1]

[0010] In Equation 1, X1 to X4 can all be independently B(R) a ), N(R b ), C(R c (R) d ), O, S, or Se, and a to d can each be an independent integer from 0 to 4. R a To R d R1 to R4 can each be independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms, and L can be a substituted or unsubstituted divalent triterpenoid group or a substituted or unsubstituted divalent carboronyl group.

[0011] In the embodiments, the polycyclic compound represented by Formula 1 can be represented by Formula 1-1.

[0012] [Equation 1-1]

[0013] In Equation 1-1, X1 to X4, a to d, R1 to R4 and L can all be the same as those defined in Equation 1.

[0014] In the embodiments, L can be a group represented by any one of L-1 to L-4.

[0015]

[0016] Between L-2 and L-4, " "It can be BH, and" "It can be C."

[0017] In the embodiments, R1 to R4 can each be independently tert-butyl, substituted or unsubstituted phenyl, or substituted or unsubstituted biphenyl.

[0018] In the embodiments, X1 to X4 can be the same.

[0019] In an embodiment, the emission layer may be a delayed fluorescence emission layer comprising a host and a dopant, and the dopant may comprise a polycyclic compound.

[0020] In the embodiments, the polycyclic compound represented by Formula 1 may be selected from any of the compounds in group 1.

[0021] [Compound Group 1]

[0022] In compounds 4 to 6, CB can be a divalent carbon boron alkyl group.

[0023] In an embodiment, the emitting layer may include: a first body; a second body, different from the first body; an auxiliary dopant, including an organometallic complex; and a light-emitting dopant, wherein the light-emitting dopant may include a polycyclic compound.

[0024] In the embodiments, the first body may include any one selected from compounds HT-01 to HT-09.

[0025]

[0026] In the embodiments, the second body may include any one selected from compounds ET-01 to ET-06.

[0027]

[0028] In the embodiments, the auxiliary dopant may include at least one selected from the compound group P.

[0029] [Compound Group P]

[0030]

[0031]

[0032]

[0033] In one embodiment, the emitting layer may emit blue light having a center wavelength in the range of about 450 nm to about 470 nm.

[0034] In an embodiment, the light-emitting diode may further include a capping layer disposed on the second electrode, and the refractive index of the capping layer may be equal to or greater than about 1.6.

[0035] In an embodiment, the light-emitting diode may include: a first electrode; a second electrode disposed on the first electrode; and an emitting layer disposed between the first electrode and the second electrode. The emitting layer may include: a first hole transport host; a second electron transport host, different from the first hole transport host; an auxiliary dopant; and a light-emitting dopant, different from the auxiliary dopant, and the light-emitting dopant may be a polycyclic compound represented by Formula 1.

[0036] [Formula 1]

[0037] In Equation 1, X1 to X4 can all be independently B(R) a ), N(R b ), C(R c (R) d ), O, S, or Se, and a to d can each be an independent integer from 0 to 4. R a To R d R1 to R4 can each be independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms, and L can be a substituted or unsubstituted divalent triterpenoid group or a substituted or unsubstituted divalent carboronyl group. Attached Figure Description

[0038] The accompanying drawings are included to provide a further understanding of the embodiments, and are incorporated in and constitute a part of this specification. The drawings illustrate the disclosed embodiments and their principles. The above and other aspects and features of the disclosure will become more apparent from the detailed description of the disclosed embodiments with reference to the accompanying drawings, in which: Figure 1 This is a plan view showing a display device according to an embodiment; Figure 2 This is a schematic cross-sectional view of a display device according to an embodiment; Figure 3 This is a schematic cross-sectional view showing a light-emitting diode according to an embodiment; Figure 4 This is a schematic cross-sectional view showing a light-emitting diode according to an embodiment; Figure 5 This is a schematic cross-sectional view showing a light-emitting diode according to an embodiment; Figure 6 This is a schematic cross-sectional view showing a light-emitting diode according to an embodiment; Figure 7 A schematic cross-sectional view of a display device according to an embodiment; and Figure 8 This is a schematic cross-sectional view of a display device according to an embodiment. Detailed Implementation

[0039] The disclosure will now be described more fully below with reference to the accompanying drawings, in which embodiments are illustrated. However, this disclosure may be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0040] In the accompanying drawings, the dimensions, thickness, ratios, and sizes of components may be exaggerated for ease of description and clarity. The same reference numerals always refer to the same components.

[0041] In this description, it will be understood that when an element (or region, layer, portion, etc.) is referred to as being "on," "connected to," or "bonded to" another element, the element (or region, layer, portion, etc.) may be directly on, connected to, or bonded to the other element, or one or more intervening elements may exist between them. In a similar sense, when an element (or region, layer, portion, etc.) is described as "covering" another element, the element (or region, layer, portion, etc.) may directly cover the other element, or one or more intervening elements may exist between them.

[0042] In the description, when an element is "directly on" another element, "directly connected to" another element, or "directly bonded to" another element, there is no intermediary element. For example, "directly on" could mean setting two layers or two elements without any additional elements such as adhesive elements between them.

[0043] As used herein, unless the context clearly indicates otherwise, expressions used in the singular (such as “a,” “one,” and “the”) are also intended to include the plural form.

[0044] As used herein, the term “and / or” includes any and all combinations of one or more of the relevant listed items. For example, “A and / or B” can be understood to mean “A, B, or A and B”. The terms “and” and “or” can be used in a connecting or separating sense and can be understood as equivalent to “and / or”.

[0045] For purposes of meaning and interpretation, the term "at least one of..." is intended to include the meaning of "selected from at least one of...". For example, "at least one of A and B" can be understood to mean "A, B, or A and B". When the term "at least one of..." follows a list of elements, it modifies the entire list of elements, not individual elements in the list.

[0046] 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 only used to distinguish one element from another. Thus, without departing from the publicly disclosed teachings, a first element may be referred to as a second element. Similarly, without departing from the scope of the disclosure, a second element may be referred to as a first element.

[0047] For ease of description, spatial relative terms such as “below,” “under,” “lower,” “above,” and “upper” are used herein to describe the relationship between one element or component and another, as shown in the accompanying drawings. It will be understood that, in addition to the orientations depicted in the drawings, the spatial relative terms are intended to cover different orientations of the device during use or operation. For example, in the case where the device shown in the drawings is flipped, a device located “below” or “under” another device may be placed “above” the other device. Therefore, the descriptive term “below” can include both a lower position and an upper position. The device may also be oriented in other directions, and thus the spatial relative terms can be interpreted differently depending on the orientation.

[0048] Given the measurements discussed and the errors associated with the measurement of the quantities (i.e., the limitations of the measurement system), the terms “about” or “approximately” as used herein include the stated values ​​and mean within an acceptable range of deviation as determined by one of ordinary skill in the art. For example, “about” may mean within one or more standard deviations, or within ±20%, ±10%, or ±5% of the stated values.

[0049] It should be understood that the terms “comprising,” “including,” “having,” “containing,” and variations thereof are intended to indicate the presence of the stated features, wholes, steps, operations, elements, components, or combinations thereof in the disclosure, but do not preclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, or combinations thereof.

[0050] Unless otherwise defined or implied herein, all terms used (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, unless clearly defined in the specification, terms (such as those defined in common dictionaries) shall be interpreted as having a meaning consistent with their meaning in the context of the relevant field and shall not be interpreted in an idealized or overly formalized sense.

[0051] In the description, the term "substituted or unsubstituted" can mean a group substituted or unsubstituted by at least one substituent selected from the group consisting of a deuterium atom, a halogen atom, a cyano group, a nitro group, an amino group (or an amino group), a silyl group, an oxygen group, a thio group, a sulfinyl group, a sulfonyl group, a carbonyl group, a boron group, a phosphonooxide group, a phosphonosulfate group, an alkyl group, an alkenyl group, an alkoxy group, a cycloalkyl group, an aryl group, and a heterocyclic group. Each of the above substituents can itself be substituted or unsubstituted. For example, biphenyl can be interpreted as an aryl group or as a phenyl group substituted with a phenyl group.

[0052] In the description, the term "bonded to an adjacent group to form a ring" can mean a group that bonds to an adjacent group to form a substituted or unsubstituted hydrocarbon ring or a substituted or unsubstituted heterocyclic ring. Hydrocarbon rings can include aliphatic and aromatic hydrocarbon rings. Heterocyclic rings can include aliphatic and aromatic heterocyclic rings. Both hydrocarbon rings and heterocyclic rings can be monocyclic or polycyclic. A ring formed by groups bonded to each other can attach to another ring to form a spirostructure.

[0053] In the description, the term "adjacent group" can mean a substituent that substitutes for an atom directly bonded to the atom substituted by the corresponding substituent, another substituent that substitutes for the atom substituted by the corresponding substituent, or a substituent located spatially closest to the corresponding substituent. For example, the two methyl groups in 1,2-dimethylbenzene can be interpreted as "adjacent groups," and the two ethyl groups in 1,1-diethylcyclopentane can be interpreted as "adjacent groups." Similarly, the two methyl groups in 4,5-dimethylphenanthrene can be interpreted as "adjacent groups."

[0054] In the description, examples of halogen atoms may include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0055] In the description, alkyl groups can be straight-chain, branched, or cyclic. The number of carbon atoms in an alkyl group can be 1 to 50, 1 to 30, 1 to 20, 1 to 10, or 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-octyldodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, 2-ethylhexadecyl, 2-butylhexadecyl, 2-hexylhexadecyl, 2-octylhexadecyl, heptadecanyl, octadecyl, nonadecanyl, eicosyl, 2-ethyleicosyl, 2-butyleicosyl, 2-hexyleicosyl, 2-octyleicosyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecanyl, hexadecyl, octadecyl, nonadecanyl, triadecyl, etc., but not limited to these.

[0056] In the description, the hydrocarbon cyclogroup can be any functional group or substituent derived from an aliphatic hydrocarbon ring. The hydrocarbon cyclogroup can be a saturated hydrocarbon cyclogroup having 5 to 20 cyclic carbon atoms.

[0057] In the description, the aryl group can be any functional group or substituent derived from an aromatic hydrocarbon ring. The aryl group can be monocyclic or polycyclic. The number of cyclic carbon atoms in the aryl group can be 6 to 30, 6 to 20, or 6 to 15. Examples of aryl groups can include, but are not limited to, phenyl, naphthyl, fluorenyl, anthracene, phenanthryl, biphenyl, triphenyl, tetraphenyl, pentaphenyl, hexaphenyl, benzo[9,10]phenanthryl, pyrene, benzofluoranthracene, phenyl, etc.

[0058] In the description, the fluorene group can be substituted, and two substituents can combine with each other to form a spirostructure. Examples of substituted fluorene groups are given below. However, the embodiments are not limited to these.

[0059]

[0060] In the description, a heterocyclic group can be any functional group or substituent derived from a ring containing at least one of B, O, N, P, Si, and S as a heteroatom. Heterocyclic groups can include aliphatic and aromatic heterocyclic groups. Aromatic heterocyclic groups can be heteroaryl groups. Both aliphatic and aromatic heterocycles can be monocyclic or polycyclic.

[0061] In the description, the heterocyclic group may contain at least one of B, O, N, P, Si, and S as a heteroatom. When the heterocyclic group contains two or more heteroatoms, the two or more heteroatoms may be the same as or different from each other. The heterocyclic group may be a monocyclic or polycyclic heterocyclic group and may include a heteroaryl group. The number of cyclic carbon atoms in the heterocyclic group may be 2 to 30, 2 to 20, or 2 to 10.

[0062] In the description, the aliphatic heterocyclic group may contain at least one of B, O, N, P, Si, and S as a heteroatom. The number of cyclic carbon atoms in the aliphatic heterocyclic group may be 2 to 30, 2 to 20, or 2 to 10. Examples of aliphatic heterocyclic groups may include, but are not limited to, ethylene oxide, thiopropylcycloalkyl, pyrrolyl, piperidinyl, tetrahydrofuranyl, tetrahydrothiophenyl, thiocyclopentyl, tetrahydropyranyl, 1,4-dioxane, etc.

[0063] In the description, a heteroaryl group may include at least one of B, O, N, P, Si, and S as a heteroatom. When a heteroaryl group contains two or more heteroatoms, the two or more heteroatoms may be the same as or different from each other. The heteroaryl group may be a monocyclic heteroaryl or a polycyclic heteroaryl. The number of cyclic carbon atoms in the heteroaryl group may be 2 to 30, 2 to 20, or 2 to 10. Examples of heteroaryl groups may include, but are not limited to, thienyl, furanyl, pyrrolyl, imidazolyl, triazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, acridineyl, pyridazinyl, quinolinyl, quinazolinyl, quinoxazinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, pyrazinopyrazinyl, 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.

[0064] In the description, except that arylene is a divalent group, the above description of aryl can be applied to arylene. Except that heteroarylene is a divalent group, the above description of heteroarylene can be applied to heteroarylene.

[0065] In the description, silane may include alkylsilane and arylsilane. Examples of silane may include, but are not limited to, trimethylsilane, triethylsilane, tert-butyldimethylsilane, propyldimethylsilane, triphenylsilane, diphenylsilane, phenylsilane, etc.

[0066] In the description, there is no specific limitation on the number of carbon atoms in the amino group, but it can be from 1 to 30. Amino groups can include alkylamino, aromaticamino, or heteroaromaticamino groups. Examples of amino groups include, but are not limited to, methylamino, dimethylamino, phenylamino, diphenylamino, naphthylamino, 9-methyl-anthraamino, etc.

[0067] In the description, there is no specific limitation on the number of carbon atoms in the carbonyl group, but it can be from 1 to 40, 1 to 30, or 1 to 20. For example, the carbonyl group can have a structure selected from, but is not limited to, the following groups.

[0068]

[0069] In the description, there is no specific limitation on the number of carbon atoms in the sulfinyl and sulfonyl groups, but they can be from 1 to 30. The sulfinyl group can include alkylsulfinyl and arylsulfinyl groups. The sulfonyl group can include alkylsulfonyl and arylsulfonyl groups.

[0070] In the description, a thio group can include alkylthio and arylthio. A thio group can be a sulfur atom bonded to an alkyl or aryl group as defined above. Examples of thio groups can include, but are not limited to, methylthio, ethylthio, propanethio, pentanethio, hexanethio, octanethio, dodecanethio, cyclopentanethio, cyclohexanethio, phenylthio, naphthio, etc.

[0071] In the description, an oxygen group can be an oxygen atom bonded to an alkyl or aryl group as defined above. Oxide groups can include alkoxy and aryloxy groups. Alkoxy groups can be straight-chain, branched, or cyclic. There is no specific limitation on the number of carbon atoms in an alkoxy group, but it can be, for example, 1 to 20 or 1 to 10. Examples of oxygen groups can include, but are not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, butoxy, pentoxy, hexoxy, octoxy, nonoxy, decoxy, benzyloxy, etc.

[0072] In the description, a boron group can be a boron atom bonded to an alkyl or aryl group as defined above. A boron group can include alkylboron and arylboron groups. Examples of boron groups include, but are not limited to, dimethylboron, diethylboron, tert-butylmethylboron, diphenylboron, phenylboron, etc.

[0073] In the description, the alkenyl group can be straight-chain or branched. There is no specific limitation on the number of carbon atoms in the alkenyl group, but it can be 2 to 30, 2 to 20, or 2 to 10. Examples of alkenyl groups can include, but are not limited to, vinyl, 1-butenyl, 1-pentenyl, 1,3-butadienyl, styryl, styrylvinyl, etc.

[0074] In the description, there is no specific limitation on the number of carbon atoms in the amino group, but it can be from 1 to 30. The amino group can include alkylamino and aromatic amino groups. Examples of amino groups can include, but are not limited to, methylamino, dimethylamino, aniline, diphenylamino, naphthylamino, 9-methyl-anthraamino, etc.

[0075] In the description, examples of alkyl groups may include alkoxy, alkylthio, alkylsulfinyl, alkylsulfonyl, alkylaryl, alkylamino, alkylboronyl, alkylsilyl, and alkylamino.

[0076] In the description, examples of aryl groups may include aryloxy, arylthio, arylsulfinyl, arylsulfonyl, arylamino, arylboryl, arylsilyl, and arylamino.

[0077] In the description, a direct-connect key can be a single key.

[0078] In the description, " "", Both "" and * represent associative positions in the correspondence.

[0079] In the following description, embodiments will be illustrated with reference to the accompanying drawings.

[0080] Figure 1 This is a plan view showing an embodiment of the display device DD. Figure 2 This is a schematic cross-sectional view of the display device DD in the embodiment. Figure 2 It shows the corresponding Figure 1 A schematic cross-sectional view of the section along line I-I'.

[0081] The display device DD may include a display panel DP and an optical layer PP disposed on the display panel DP. The display panel DP includes light-emitting diodes ED-1, ED-2, and ED-3. The display device DD may include multiple light-emitting diodes ED-1, ED-2, and ED-3. The optical layer PP may be disposed on the display panel DP and can control the reflected light from external light at the display panel DP. The optical layer PP may include, for example, a polarizing layer or a color filter layer. Although not shown in the figures, in embodiments, the optical layer PP may be omitted from the display device DD.

[0082] The substrate BL can be disposed on the optical layer PP. The substrate BL can provide a substrate surface on which the optical layer PP is disposed. The substrate BL can be a glass substrate, a metal substrate, a plastic substrate, etc. However, the embodiments are not limited to these, and the substrate BL can include an inorganic layer, an organic layer, or a composite material layer. Although not shown in the figures, the substrate BL may be omitted in the embodiments.

[0083] The display device DD according to an embodiment may further include a filler layer (not shown). The filler layer (not shown) may be disposed between the display element layer DP-ED and the substrate BL. The filler layer (not shown) may be an organic material layer. The filler layer (not shown) may include at least one selected from acrylic resin, silicone resin and epoxy resin.

[0084] The display panel DP may include a substrate layer BS, a circuit layer DP-CL disposed on the substrate layer BS, and a display element layer DP-ED. The display element layer DP-ED may include a pixel limiting layer PDL, light-emitting diodes ED-1, ED-2, and ED-3 disposed in the pixel limiting layer PDL, and an encapsulation layer TFE disposed on the light-emitting diodes ED-1, ED-2, and ED-3.

[0085] The substrate layer BS can provide a substrate surface on which the display element layer DP-ED is disposed. The substrate layer BS can be a glass substrate, a metal substrate, a plastic substrate, etc. However, the embodiments are not limited to these, and the substrate layer BS can include an inorganic layer, an organic layer, or a composite material layer.

[0086] In this embodiment, the circuit layer DP-CL may be disposed on the substrate layer BS, and the circuit layer DP-CL may include transistors (not shown). Each transistor (not shown) may include a control electrode, an input electrode, and an output electrode. For example, the circuit layer DP-CL may include a switching transistor and a driving transistor to drive the light-emitting diodes ED-1, ED-2, and ED-3 of the display element layer DP-ED.

[0087] LEDs ED-1, ED-2, and ED-3 can all have features described later. Figures 3 to 6 The structure of the light-emitting diode ED in the embodiments is shown. Light-emitting diodes ED-1, ED-2 and ED-3 may each include a first electrode EL1, a hole transport region HTR, an emitter layer EML-R, EML-G and EML-B, an electron transport region ETR and a second electrode EL2.

[0088] Figure 2An embodiment is shown in which the emitter layers EML-R, EML-G, and EML-B of light-emitting diodes ED-1, ED-2, and ED-3 are disposed within an opening OH defined in the pixel defining layer PDL, and the hole transport region HTR, electron transport region ETR, and second electrode EL2 are all disposed throughout the common layer of light-emitting diodes ED-1, ED-2, and ED-3. However, the embodiment is not limited thereto, and although not shown in Figure 2 As shown, however, in an embodiment, the hole transport region HTR and the electron transport region ETR can both be patterned and disposed within the opening OH defined in the pixel defining layer PDL. For example, in an embodiment, the hole transport region HTR, the emitter layers EML-R, EML-G, and EML-B, and the electron transport region ETR of light-emitting diodes ED-1, ED-2, and ED-3 can all be patterned and disposed by an inkjet printing method.

[0089] The encapsulation layer TFE can cover the light-emitting diodes ED-1, ED-2, and ED-3. The encapsulation layer TFE can seal other portions of the display element layer DP-ED. The encapsulation layer TFE can be a thin-film encapsulation layer. The encapsulation layer TFE can be a single layer or a stack of multiple layers. The encapsulation layer TFE can include at least one insulating layer. According to an embodiment, the encapsulation layer TFE can include at least one inorganic film (hereinafter, encapsulating inorganic film). According to an embodiment, the encapsulation layer TFE can include at least one organic film (hereinafter, encapsulating organic film) and at least one encapsulating inorganic film.

[0090] Encapsulating inorganic films can protect the display element layer (DP-ED) from moisture and / or oxygen, while encapsulating organic films can protect the DP-ED from foreign matter such as dust particles. Encapsulating inorganic films may include silicon nitride, silicon oxynitride, silicon oxide, titanium dioxide, aluminum oxide, etc., but the embodiments are not limited thereto. Encapsulating organic films may include acrylic compounds, epoxy compounds, etc. Encapsulating organic films may include photopolymerizable organic materials, and the embodiments are not limited thereto.

[0091] The encapsulation layer TFE can be disposed on the second electrode EL2, and can be configured to fill the opening OH.

[0092] Reference Figure 1 and Figure 2 The display device DD may include a non-light-emitting area NPXA and light-emitting areas PXA-R, PXA-G, and PXA-B. The light-emitting areas PXA-R, PXA-G, and PXA-B may all be areas that emit light generated from each of the light-emitting diodes ED-1, ED-2, and ED-3. The light-emitting areas PXA-R, PXA-G, and PXA-B may be spaced apart from each other on a plane.

[0093] Each of the light-emitting regions PXA-R, PXA-G, and PXA-B can be a region separated from each other by a pixel-defining layer PDL. The non-light-emitting region NPXA can be the region between adjacent light-emitting regions PXA-R, PXA-G, and PXA-B, and can correspond to the pixel-defining layer PDL. In the description, each of the light-emitting regions PXA-R, PXA-G, and PXA-B can correspond to a pixel. The pixel-defining layer PDL can separate light-emitting diodes ED-1, ED-2, and ED-3. The emitting layers EML-R, EML-G, and EML-B of light-emitting diodes ED-1, ED-2, and ED-3 can be disposed in openings OH defined by the pixel-defining layer PDL and separated from each other.

[0094] The luminous regions PXA-R, PXA-G, and PXA-B can be grouped according to the color of the light emitted from each of the light-emitting diodes ED-1, ED-2, and ED-3. Figure 1 and Figure 2 In the display device DD of the embodiment shown, three light-emitting regions PXA-R, PXA-G, and PXA-B, which emit red, green, and blue light respectively, are presented as an example. For example, the display device DD of the embodiment may include red light-emitting region PXA-R, green light-emitting region PXA-G, and blue light-emitting region PXA-B, which are different from each other.

[0095] In the display device DD according to an embodiment, light-emitting diodes ED-1, ED-2, and ED-3 can emit light with different wavelength ranges. For example, in an embodiment, the display device DD may include a first light-emitting diode ED-1 emitting red light, a second light-emitting diode ED-2 emitting green light, and a third light-emitting diode ED-3 emitting blue light. For example, the red emitting region PXA-R, the green emitting region PXA-G, and the blue emitting region PXA-B of the display device DD can correspond to the first light-emitting diode ED-1, the second light-emitting diode ED-2, and the third light-emitting diode ED-3, respectively.

[0096] However, the embodiments are not limited thereto, and the first light-emitting diode ED-1, the second light-emitting diode ED-2, and the third light-emitting diode ED-3 may emit light within the same wavelength range or emit light within at least one different wavelength range. For example, the first light-emitting diode ED-1, the second light-emitting diode ED-2, and the third light-emitting diode ED-3 may all emit blue light.

[0097] According to an embodiment, the light-emitting regions PXA-R, PXA-G, and PXA-B in the display device DD can be arranged in the form of stripes. (Refer to...) Figure 1The red emitting region PXA-R, the green emitting region PXA-G, and the blue emitting region PXA-B can all be arranged along the second direction axis DR2. In another embodiment, the red emitting region PXA-R, the green emitting region PXA-G, and the blue emitting region PXA-B can be arranged alternately and sequentially along the first direction axis DR1.

[0098] Figure 1 and Figure 2 The luminescent regions PXA-R, PXA-G, and PXA-B are shown to be similar in size, but the embodiments are not limited to this, and the luminescent regions PXA-R, PXA-G, and PXA-B may differ in size from each other depending on the wavelength range of the emitted light. The area of ​​the luminescent regions PXA-R, PXA-G, and PXA-B can be the area defined in a planar diagram by a first directional axis DR1 and a second directional axis DR2 intersecting a third directional axis DR3.

[0099] The arrangement of the luminescent regions PXA-R, PXA-G, and PXA-B is not limited to... Figure 1 The arrangement shown can be configured in various combinations according to the display quality characteristics required by the display device DD, wherein the order of the red emitting areas PXA-R, green emitting areas PXA-G, and blue emitting areas PXA-B is arranged. For example, the emitting areas PXA-R, PXA-G, and PXA-B can be arranged in a pentiline manner. ® The structure may be arranged in a rhomboid pattern.

[0100] In the embodiments, the area of ​​each of the light-emitting regions PXA-R, PXA-G, and PXA-B may differ from each other in size. For example, in an embodiment, the green light-emitting region PXA-G may be smaller in size than the blue light-emitting region PXA-B, but the embodiments are not limited thereto.

[0101] In the following text, Figures 3 to 6 All are schematic cross-sectional views showing a light-emitting diode (ED) according to an embodiment. Figure 3 As shown, a light-emitting diode (ED) according to an embodiment may include a first electrode EL1, a second electrode EL2 facing the first electrode EL1, and at least one functional layer disposed between the first electrode EL1 and the second electrode EL2. The at least one functional layer may include a hole transport region (HTR), an emitter layer (EML), and an electron transport region (ETR) stacked sequentially. For example, the ED of the embodiment 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.

[0102] and Figure 3 compared to, Figure 4A schematic cross-sectional view of a light-emitting diode (LED) 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). Figure 3 compared to, Figure 5 A schematic cross-sectional view of a light-emitting diode (ED) 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, and wherein the electron transport region ETR includes an electron injection layer EIL, an electron transport layer ETL, and a hole blocking layer HBL. Figure 4 compared to, Figure 6 A schematic cross-sectional view of a light-emitting diode (ED) in which a capping layer (CPL) disposed on a second electrode (EL2) is shown.

[0103] According to embodiments, a light-emitting diode (ED) may include a polycyclic compound, as described later, in the emitter layer (EML). In a display device DD comprising multiple light-emitting regions PXA-R, PXA-G, and PXA-B (...),... Figure 2 In the ), the emitting layer EML constituting at least one emitting region may include a polycyclic compound according to an embodiment, which will be described later.

[0104] In the light-emitting diode (ED) according to the embodiment, the first electrode EL1 is conductive. The first electrode EL1 may be formed of a metallic material, a metal alloy, or a conductive compound. The first electrode EL1 may be an anode or a cathode. However, the embodiment is not limited thereto. In the embodiment, the first electrode EL1 may be a pixel electrode. The first electrode EL1 may be a transmissive electrode, a transmissive-reflective electrode, or a reflective electrode. The first electrode EL1 may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, In, Sn, Zn, their oxides, their compounds, or mixtures thereof.

[0105] When the first electrode EL1 is a transmission electrode, it may comprise a transparent metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), and indium tin zinc oxide (ITZO). When the first electrode EL1 is a transmissive-reflective electrode or a reflective electrode, it may comprise Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, compounds thereof, mixtures thereof (e.g., a mixture of Ag and Mg), or a material having a multilayer structure comprising two or more of those selected from them (e.g., LiF / Ca (e.g., a stacked structure of LiF and Ca) or LiF / Al (e.g., a stacked structure of LiF and Al)). In embodiments, the first electrode EL1 may have a multilayer structure comprising a reflective or transmissive-reflective film formed from the above materials and a transparent conductive film formed from indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), etc. For example, the first electrode EL1 may have a three-layer structure of ITO / Ag / ITO, but the embodiments are not limited thereto. The first electrode EL1 may include the aforementioned metallic material, a combination of two or more metallic materials selected from the aforementioned metallic materials, or an oxide of the aforementioned metallic materials. The first electrode EL1 may have a thickness in the range of about 700 Å to about 10000 Å. For example, the first electrode EL1 may have a thickness in the range of about 1000 Å to about 3000 Å.

[0106] A hole transport region (HTR) is disposed on the first electrode EL1. The hole transport region (HTR) may include at least one of a hole injection layer (HIL), a hole transport layer (HTL), a buffer layer (not shown), a light-emitting auxiliary layer (not shown), and an electron blocking layer (EBL). The hole transport region (HTR) may have a thickness, for example, in the range of about 50 Å to about 15000 Å.

[0107] Hole transport region (HTR) can be a layer formed of a single material, a layer formed of different materials, or a multilayer structure with layers formed of different materials.

[0108] For example, the hole transport region HTR can have a monolayer structure formed by a hole injection layer HIL or a hole transport layer HTL, or a monolayer structure formed by a hole injection material or a hole transport material. For example, the hole transport region HTR can have a monolayer structure formed by different materials, or a structure in which hole injection layer HIL / hole transport layer HTL, hole injection layer HIL / hole transport layer HTL / buffer layer (not shown), hole injection layer HIL / buffer layer (not shown), hole transport layer HTL / buffer layer (not shown), or hole injection layer HIL / hole transport layer HTL / electron blocking layer EBL are stacked from the first electrode EL1 in their respective stated order, but the embodiments are not limited thereto.

[0109] Hole transport regions (HTRs) can be formed using various methods, such as vacuum deposition, spin coating, casting, Langmuir-Blodget (LB) method, inkjet printing, laser printing, and laser-induced thermal imaging (LITI) method.

[0110] The hole transport region (HTR) may include a compound represented by the formula H-1 below.

[0111] [Formula H-1]

[0112] In Formula H-1 above, L1 and L2 can each be independently a straight-linked, substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms. In Formula H-1, a and b can each be independently an integer from 0 to 10. When a or b is 2 or greater, the plurality of L1 groups and the plurality of L2 groups can each be independently a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms.

[0113] In formula H-1, Ar1 and Ar2 can each be independently a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms. In formula H-1, Ar3 can be a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms.

[0114] The compound represented by Formula H-1 above can be a monoamine compound. In another embodiment, the compound represented by Formula H-1 can be a diamine compound in which at least one of Ar1 to Ar3 may include an amino group as a substituent. For example, the compound represented by Formula H-1 can be a carbazole compound comprising a substituted or unsubstituted carbazole group in at least one of Ar1 and Ar2, or a fluorene compound comprising a substituted or unsubstituted fluorene group in at least one of Ar1 and Ar2.

[0115] The compound represented by formula H-1 can be any one selected from the group of compounds H below. However, the compounds listed in group H are presented as examples, and the compound represented by formula H-1 is not limited to the compounds listed in group H below.

[0116] [Compound Group H]

[0117]

[0118]

[0119]

[0120] Hole transport regions (HTRs) can include phthalocyanine compounds (such as copper phthalocyanine), N,N'-diphenyl-N,N'-bis-[4-(phenyl-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-styrene) Sulfonates (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 or NPD), triphenylamine-containing polyether ketone (TPAPEK), 4-isopropyl-4'-methyldiphenyliodonium tetra(pentafluorophenyl)borate, dipyrazino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexaonitrile (HAT-CN), etc.

[0121] Hole transport regions (HTRs) can include carbazole derivatives (such as N-phenylcarbazole and 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'-cyclohexylbis[N,N-bis(4-methylphenyl)aniline] (TAPC), 4,4'-bis[N,N'-(3-tolyl)amino]-3,3'-dimethylbiphenyl (HMTPD), 1,3-bis(N-carbazolyl)benzene (mCP), etc.

[0122] Hole transport regions (HTRs) may include 9-(4-tert-butylphenyl)-3,6-bis(triphenylsilyl)-9H-carbazole (CzSi), 9-phenyl-9H-3,9'-bicarbazole (CCP), 1,3-bis(1,8-dimethyl-9H-carbazole-9-yl)benzene (mDCP), etc.

[0123] The hole transport region HTR may include the compound of the hole transport region HTR described above in at least one of the hole injection layer HIL, the hole transport layer HTL, and the electron blocking layer EBL.

[0124] The hole transport region HTR can have a thickness ranging from about 100 Å to about 10,000 Å. For example, the hole transport region HTR can have a thickness ranging from about 100 Å to about 5,000 Å. When the hole transport region HTR includes a hole injection layer HIL, the hole injection layer HIL can have a thickness ranging from about 30 Å to about 1,000 Å. When the hole transport region HTR includes a hole transport layer HTL, the hole transport layer HTL can have a thickness ranging from about 30 Å to about 1,000 Å. When the hole transport region HTR includes an electron blocking layer EBL, the electron blocking layer EBL can have a thickness ranging from about 10 Å to about 1,000 Å. When the thicknesses of the hole transport region HTR, the hole injection layer HIL, the hole transport layer HTL, and the electron blocking layer EBL satisfy the above ranges, satisfactory hole transport properties can be obtained without significantly increasing the driving voltage.

[0125] In addition to the materials described above, the hole transport region (HTR) may also include a charge-generating material to increase 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 include, but is not limited to, at least one of metal halide compounds, quinone derivatives, metal oxides, and cyano-containing compounds. For example, p-dopers can include, but are not limited to, metal halide compounds (such as CuI and RbI), quinone derivatives (such as tetracyanoquinone dimethyl ether (TCNQ) and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinone dimethyl ether (F4-TCNQ)), metal oxides (such as tungsten oxide and molybdenum oxide), cyano-containing compounds (such as dipyrazino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexanitrile (HAT-CN) and 4-[[2,3-bis[cyano-(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropyl]-cyanomethyl]-2,3,5,6-tetrafluorobenzyl nitrile (NDP9)).

[0126] 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 buffer layer (not shown) and an electron blocking layer EBL. The buffer layer (not shown) can compensate for the resonant distance according to the wavelength of light emitted from the emission layer EML, and thus can increase luminous efficiency. Materials that can be included in the hole transport region HTR can be used as materials included in the buffer layer (not shown). The electron blocking layer EBL is a layer that prevents electrons from being injected from the electron transport region ETR into the hole transport region HTR.

[0127] The emitter layer (EML) is disposed on the hole transport region (HTR). The emitter layer (EML) can have a thickness, for example, in the range of about 100 Å to about 1000 Å. For example, the emitter layer (EML) can have a thickness in the range of about 100 Å to about 300 Å. The emitter layer (EML) can be a layer formed of a single material, a layer formed of different materials, or a multilayer structure having layers formed of different materials.

[0128] The light-emitting diode (ED) according to the embodiments may include the polycyclic compound of the embodiments in the emitter layer (EML). The polycyclic compound of the embodiments may be represented by Formula 1 below.

[0129] [Formula 1]

[0130] In Equation 1, X1 to X4 can all be independently B(R) a ), N(R b ), C(R c (R) d), O, S or Se. In Equation 1, R a To R d Each of the following can be independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms.

[0131] In this embodiment, X1 to X4 may be the same. However, the embodiment is not limited thereto, and at least one of X1 to X4 may be different from the others.

[0132] In the embodiment, R a To R d All of them can be independently substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, etc. However, the examples are not limited thereto.

[0133] In Formula 1, a to d can each be an integer from 0 to 4 independently, and R1 to R4 can each be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms.

[0134] When a to d are 1 or greater, R1 to R4 can each be independently a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms. For example, in the embodiments, R1 to R4 can each be independently a tert-butyl group, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted biphenyl group. However, the embodiments are not limited thereto.

[0135] In Formula 1, L can be a substituted or unsubstituted divalent triterpenoid group or a substituted or unsubstituted divalent carborane alkyl group. For example, L can be an unsubstituted divalent triterpenoid group or an unsubstituted divalent carborane alkyl group.

[0136] In Formula 1, L can be any of the groups represented by L-1 to L-4 below.

[0137]

[0138] L-2 to L-4 all represent divalent carbon boron alkyl groups, and in L-2 to L-4, " "It's BH, and..." "" indicates the cyclic atom C. L-2 indicates the ortho-carborane alkyl group, L-3 indicates the meta-carborane alkyl group, and L-4 indicates the para-carborane alkyl group.

[0139] For example, the polycyclic compound according to the embodiments can have a compound skeletal structure in the form of a dimer linked by a large (bulky) linking group. The polycyclic compound of the embodiments can have a structure in which two DABNA derivatives containing boron (B) atoms are linked by a linking group. In the embodiments, the two DABNA derivatives linked by the linking group can be symmetrical with respect to the linking group. However, the embodiments are not limited thereto.

[0140] The polycyclic compounds of the embodiments, in the form of dimers linked by linking groups, prevent aggregation between adjacent polycyclic compounds, thereby improving film quality during the formation of the organic layer of a light-emitting diode (ED). The polycyclic compounds of the embodiments can be used with auxiliary dopants as energy transfer agents to increase Forster energy transfer and prevent Dexter energy transfer, resulting in extended lifetime and increased efficiency of the ED that includes the polycyclic compounds of the embodiments in the emitter layer EML.

[0141] The polycyclic compounds of the embodiments represented by Formula 1 can be represented by Formula 1-1 below.

[0142] [Equation 1-1]

[0143] In Formula 1-1 above, X1 to X4, a to d, R1 to R4, and L can all be the same as defined in Formula 1. For example, the polycyclic compound of the embodiment may include a divalent triterpenoid group or a divalent carborane alkyl group as a linking group, and may have a structure in which polycyclic derivatives referred to as DABNA derivatives are linked to each other by linking groups at the para position opposite to the boron atom of the polycyclic derivative referred to as DABNA derivative. Two DABNA derivatives linked by linking group L may have the same structure. However, the embodiment is not limited thereto.

[0144] The polycyclic compound of the embodiment represented by Formula 1 may be any one selected from the compound group 1 below. The light-emitting diode (ED) of the embodiment may include at least one polycyclic compound selected from the compound group 1 below in the emitting layer EML.

[0145] [Compound Group 1]

[0146]

[0147] In compounds 4 to 6 of compound group 1, "CB" represents a divalent carborane alkyl group. For example, in compounds 4 to 6, "CB" can be represented by any of L-2 to L-4 described above. In embodiments, in compounds 4 to 6, "CB" can have the structure of L-3 as described above.

[0148] The polycyclic compounds of the embodiments represented by Formula 1 can be used as fluorescent luminescent materials or thermally activated delayed fluorescence (TADF) materials. For example, the polycyclic compounds of the embodiments can be used as luminescent dopants that emit blue light. In the embodiments, the polycyclic compounds of the embodiments can be used as TADF dopant materials.

[0149] The polycyclic compound in the embodiments may have a central emission wavelength (λ) equal to or less than about 490 nm. max The luminescent material is a polycyclic compound of Formula 1. For example, in the embodiments, the polycyclic compound of Formula 1 can be a luminescent material having a central emission wavelength in the range of about 450 nm to about 470 nm. For example, the polycyclic compound of the embodiments can be a blue thermally activated delayed fluorescence dopant. However, the embodiments are not limited thereto.

[0150] exist Figures 3 to 6 In the light-emitting diode (ED) of the embodiments shown, the emission layer EML may include a host and a dopant, and the emission layer EML may include the polycyclic compound of the embodiments described above as a dopant. In the embodiments, the dopant may include the polycyclic compound of the embodiments. Furthermore, the emission layer EML may be a delayed fluorescence emission layer.

[0151] In the light-emitting diode (ED) of the embodiments, the emitting layer (EML) may include a first host, a second host, an auxiliary dopant, and a luminescent dopant. In the embodiments, the first host and the second host may be different from each other. In the embodiments, the auxiliary dopant may include an organometallic complex. In the embodiments, the luminescent dopant may include a polycyclic compound represented by Formula 1 described above.

[0152] In this embodiment, the first body may be a hole transport body, and the second body may be an electron transport body. The first body of the emitter layer EML in this embodiment may include at least one selected from HT-01 to HT-09 below.

[0153]

[0154]

[0155]

[0156] The second body of the emitter layer EML in the embodiment may include at least one selected from ET-01 to ET-06 below.

[0157]

[0158] In the embodiment of the light-emitting diode (ED), the emitter layer (EML) may include an organometallic complex. For example, in the embodiment of the ED, the emitter layer (EML) may include an auxiliary dopant comprising an organometallic complex. In the embodiment, the auxiliary dopant included in the emitter layer (EML) may be referred to as a phosphorescent photosensitive agent. In the embodiment of the ED, the phosphorescent photosensitive agent included in the emitter layer (EML) can transfer energy to the luminescent dopant to increase the fluorescence emissivity of the luminescent dopant.

[0159] In a light-emitting diode (ED), the auxiliary dopant of the emitter layer (EML) in an embodiment may include at least one selected from the compound group P.

[0160] [Compound Group P]

[0161]

[0162]

[0163]

[0164] However, the embodiments are not limited thereto, and in another embodiment, the light-emitting diode ED may include a phosphorescent dopant material, which includes an organometallic complex as an auxiliary dopant.

[0165] The light-emitting diode (ED) of the embodiment includes an emission layer (EML) and can therefore exhibit excellent device lifetime and improved luminous efficiency characteristics. The emission layer (EML) includes a first body and a second body as described above, an auxiliary dopant comprising an organometallic complex, and a light-emitting dopant comprising a polycyclic compound of the embodiment described above.

[0166] In addition to the polycyclic compounds, the first and second bodies, and the auxiliary dopant materials described in the embodiments above, the light-emitting diode (ED) of the embodiments may also include a lower emission layer material. In the ED of the embodiments, the emission layer EML may include anthracene derivatives, pyrene derivatives, fluoranthene derivatives, phenanthrene derivatives, dihydrobenzanthene derivatives, or benzo[9,10]phenanthrene derivatives. For example, in the embodiments, the emission layer EML may include anthracene derivatives or pyrene derivatives.

[0167] exist Figures 3 to 6In the light-emitting diode (ED) of the embodiment shown, the emission layer (EML) may include a host and a dopant, and the emission layer (EML) may include a compound represented by Formula E-1 below. A compound represented by Formula E-1 below may be included as the fluorescent host material.

[0168] [Equation E-1]

[0169] In equation E-1, R 31 To R 40 Each of these groups can independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms, and can optionally be attached to an adjacent group to form a ring. In formula E-1, R 31 To R 40 It can combine with adjacent groups to form saturated hydrocarbon rings, unsaturated hydrocarbon rings, saturated heterocycles, or unsaturated heterocycles.

[0170] In E-1, c and d can both be independent integers from 0 to 5.

[0171] The compound represented by formula E-1 can be any one of compounds E1 to E19 below.

[0172]

[0173]

[0174]

[0175]

[0176]

[0177]

[0178] In an embodiment, the emitting layer EML may include a compound represented by formula E-2a or E-2b below. The compound represented by formula E-2a or E-2b below can be used as a phosphorescent host material.

[0179] [Equation E-2a]

[0180] In equation E-2a, a can be an integer from 0 to 10, and L a It can be a directly bonded, substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms. When a is 2 or greater, multiple L... a The groups can all be independently substituted or unsubstituted aryl groups having 6 to 30 cyclic carbon atoms or substituted or unsubstituted heteroaryl groups having 2 to 30 cyclic carbon atoms.

[0181] In equation E-2a, A1 to A5 can all be independently N or C(R). i R a To R i Each group may independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted amino group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms, and may optionally be attached to an adjacent group to form a ring. R a To R i It can combine with adjacent groups to form hydrocarbon rings or heterocycles containing N, O, S, etc. as cyclic atoms.

[0182] In equation E-2a, two or three of A1 to A5 can be N, and the rest of A1 to A5 can be C(R). i ).

[0183] [Equation E-2b]

[0184] In formula E-2b, Cbz1 and Cbz2 can both be independently unsubstituted carbazole groups or carbazole groups substituted with aryl groups having 6 to 30 cyclic carbon atoms. b It can be a directly bonded, substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms. In formula E-2b, b can be an integer from 0 to 10, and when b is 2 or greater, multiple L... b The groups can all be independently substituted or unsubstituted aryl groups having 6 to 30 cyclic carbon atoms or substituted or unsubstituted heteroaryl groups having 2 to 30 cyclic carbon atoms.

[0185] The compound represented by formula E-2a or E-2b may be selected from any of the compounds in group E-2 below. However, the compounds listed in group E-2 below are presented as examples, and the compounds represented by formula E-2a or E-2b are not limited to those listed in group E-2 below.

[0186] [Compound Group E-2]

[0187]

[0188]

[0189]

[0190] The emitter layer EML may also include materials commonly used in the art as the host material. For example, the emitter layer EML may include at least one of bis[2-(diphenylphosphino)phenyl]ether oxide (DPEPO), 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP), 1,3-bis(carbazol-9-yl)benzene (mCP), 2,8-bis(diphenylphospho)dibenzofuran (PPF), 4,4',4''-tris(carbazol-9-yl)-triphenylamine (TCTA), and 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi) as the host material. However, the embodiments are not limited to this, and for example, tris(8-hydroxyquinoline)aluminum (Alq3), 9,10-bis(naphthyl-2-yl)anthracene (ADN), 2-tert-butyl-9,10-bis(naphthyl-2-yl)anthracene (TBADN), stilbeneyl arylene (DSA), 4,4'-bis(9-carbazolyl)-2,2'-dimethyl-biphenyl (CDBP), 2-methyl-9,10-bis(naphthyl-2-yl)anthracene (MADN), hexaphenylcyclotriphosphazene (CP1), 1,4-bis(triphenylsilyl)benzene (UGH2), hexaphenylcyclotrisiloxane (DPSiO3), octaphenylcyclotetrasiloxane (DPSiO4), etc., can be used as host materials.

[0191] The emitter layer (EML) may include compounds represented by the formula Ma or Mb below. Compounds represented by the formula Ma or Mb below can be used as phosphorescent dopant materials. In embodiments, compounds represented by the formula Ma or Mb can be used as auxiliary dopant materials.

[0192] [Formula]

[0193] In the formula Ma above, Y1 to Y4 and Z1 to Z4 can each be independently C(R1) or N, and R1 to R4 can each be independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted amino group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms, and can optionally be incorporated into adjacent groups to form a ring. In formula Ma, m can be 0 or 1, and n can be 2 or 3. In formula Ma, when m is 0, n can be 3, and when m is 1, n can be 2.

[0194] Compounds represented by the formula Ma can be used as phosphorescent dopants. Compounds M-a1 to M-a25 below can be used as phosphorescent dopants.

[0195] The compound represented by formula Ma can be any one of compounds M-a1 to M-a21 listed below. However, compounds M-a1 to M-a21 are presented below as examples, and the compound represented by formula Ma is not limited to compounds M-a1 to M-a21.

[0196]

[0197]

[0198]

[0199]

[0200]

[0201]

[0202]

[0203] Compounds M-a1 and M-a2 can be used as red dopant materials, and compounds M-a3 to M-a25 can be used as green dopant materials.

[0204] [Formula Mb]

[0205] In formula Mb, Q1 to Q4 can each be independently C or N, and C1 to C4 can each be independently a substituted or unsubstituted hydrocarbon ring having 5 to 30 cyclic carbon atoms or a substituted or unsubstituted heterocycle having 2 to 30 cyclic carbon atoms. L21 To L 24 Each can be independently configured as a direct-connect key. , , , , , The formula Mb contains a divalent alkyl group having 1 to 20 carbon atoms (substituted or unsubstituted), an aryl group having 6 to 30 cyclic carbon atoms (substituted or unsubstituted), or a heteroaryl group having 2 to 30 cyclic carbon atoms (substituted or unsubstituted), wherein e1 to e4 can each be independently 0 or 1. In the formula Mb, R... 31 To R 39 Each of the following groups may be independently hydrogen, deuterium, halogen, cyano, substituted or unsubstituted amino, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 cyclic carbon atoms, or substituted or unsubstituted heteroaryl having 2 to 30 cyclic carbon atoms, and may optionally be attached to an adjacent group to form a ring, and d1 to d4 may each be independently an integer from 0 to 4.

[0206] Compounds represented by the formula Mb can be used as blue phosphorescent dopants or as green phosphorescent dopants. In embodiments, compounds represented by the formula Mb may be further included as auxiliary dopants in the emitter layer EML.

[0207] The compound represented by the formula Mb can be any one of compounds Mb-1 to Mb-12. However, the compounds below are presented as examples, and the compounds represented by the formula Mb are not limited to compounds Mb-1 to Mb-12.

[0208]

[0209]

[0210] In compounds Mb-1 to Mb-12, R, R 38 and R 39 Each of the following can be independently a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms.

[0211] The emitter layer EML may also include compounds represented by any one of the formulas Fa to Fc below. Compounds represented by formulas Fa to Fc below can be used as fluorescent dopant materials.

[0212] [Form Fa]

[0213] In the above formula Fa, the formula is selected from R. a To R j Both of them can be independently determined. Replace. R a To R j The un-included The remaining substitutions can all independently be hydrogen atoms, deuterium atoms, halogen atoms, cyano groups, substituted or unsubstituted amino groups, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 cyclic carbon atoms, or substituted or unsubstituted heteroaryl groups having 2 to 30 cyclic carbon atoms. In this context, Ar1 and Ar2 can each be independently a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms. For example, at least one of Ar1 and Ar2 can be a heteroaryl group containing O or S as a cyclic atom.

[0214] [Formula Fb]

[0215] In the above formula Fb, R a and R b Each of the following can be independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms, and can optionally be attached to an adjacent group to form a ring.

[0216] In formula Fb, U and V can both be independently substituted or unsubstituted hydrocarbon rings having 5 to 30 cyclic carbon atoms or substituted or unsubstituted heterocycles having 2 to 30 cyclic carbon atoms.

[0217] In formula Fb, the number of rings represented by U and V can both be independently 0 or 1. For example, in formula Fb, when the number of U or V is 1, the condensed ring can exist at the position indicated by U or V, and when the number of U or V is 0, the ring can not exist at the position indicated by U or V. When the number of U is 0 and the number of V is 1, or when the number of U is 1 and the number of V is 0, the condensed ring with a fluorene core in formula Fb can be a cyclic compound with four rings. When both U and V are 0, the condensed ring in formula Fb can be a cyclic compound with three rings. When both U and V are 1, the condensed ring with a fluorene core in formula Fb can be a cyclic compound with five rings.

[0218] In equation Fb, Ar1 to Ar4 can all be independently defined as... [Formula Fc]

[0219] In equation Fc, A1 and A2 can both be independently O, S, Se, or N(R). m ), and R m It can be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms. In formula Fc, R1 to R 11 Each group may independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted amino group, a substituted or unsubstituted boron group, a substituted or unsubstituted oxygen group, a substituted or unsubstituted thio group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms, and may optionally be attached to an adjacent group to form a ring.

[0220] In formula Fc, A1 and A2 can each independently bind to substituents of adjacent rings to form condensed rings. For example, when A1 and A2 are both independently N(R) m When A1 binds to R4 or R5 to form a ring, A2 can bind to R7 or R8 to form a ring.

[0221] The emitter layer (EML) may include styrene derivatives (e.g., 1,4-bis[2-(3-N-ethylcarbazolyl)vinyl]benzene (BCzVB), 4-(di-p-tolylamino)-4'-[(di-p-tolylamino)styrene]benzene (DPAVB) and N-(4-((E)-2-(6-((E)-4-(diphenylamino)styrene)naphth-2-yl)vinyl)phenyl)-N-phenylaniline (N-BDAVBi)), perylene and its derivatives (e.g., 2,5,8,11-tetratert-butylperylene (TBP)), pyrene and its derivatives (e.g., 1,1'-dipyrene, 1,4-dipyrenebenzene, 1,4-bis(N,N-diphenylamino)pyrene) as dopant materials.

[0222] In embodiments where multiple emitter layers (EMLs) are included, at least one emitter layer EML may include a phosphorescent dopant material. For example, metal complexes comprising iridium (Ir), platinum (Pt), osmium (Os), gold (Au), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), or thulium (Tm) can be used as phosphorescent dopant. For example, iridium(III) bis(4,6-difluorophenylpyridine-N,C2)pyridinecarboxylate (FIrpic), iridium(III) bis(2,4-difluorophenylpyridine)-tetra(1-pyrazolyl)borate (FIr6), and octaethylporphyrin platinum (PtOEP) can be used as phosphorescent dopant. However, embodiments are not limited to this.

[0223] At least one emitter layer (EML) may include quantum dot materials. Quantum dots may be II-VI compounds, III-VI compounds, I-III-VI compounds, III-V compounds, III-II-V compounds, IV-VI compounds, group IV elements, group IV compounds, or combinations thereof.

[0224] Group II-VI compounds can be: binary compounds selected from the group consisting of CdSe, CdTe, CdS, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS and mixtures thereof; ternary compounds selected from the group consisting of CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, C The group consisting of dHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS and mixtures thereof; quaternary compounds selected from the group consisting of HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe and mixtures thereof; or any combination thereof.

[0225] III-VI compounds can be: binary compounds (such as In2S3 and In2Se3); ternary compounds (such as InGaS3 and InGaSe3); or any combination thereof.

[0226] Group I-III-VI compounds can be: ternary compounds selected from the group consisting of AgInS, AgInS2, CuInS, CuInS2, AgGaS2, CuGaS2, CuGaO2, AgGaO2, AgAlO2 and any mixture thereof; quaternary compounds such as AgInGaS2 and CuInGaS2; or any combination thereof.

[0227] Group III-V compounds can be: binary compounds selected from the group consisting of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and mixtures thereof; ternary compounds selected from the group consisting of GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InAlP, InNP, InNAs, InNSb, InPAs, InPSb, and mixtures thereof; quaternary compounds selected from the group consisting of GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, and mixtures thereof; or any combination thereof. Group III-V compounds may further include Group II metals. For example, InZnP and other compounds can be selected as III-II-V group compounds.

[0228] Group IV-VI compounds can be: binary compounds selected from the group consisting of SnS, SnSe, SnTe, PbS, PbSe, PbTe, and mixtures thereof; ternary compounds selected from the group consisting of SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, and mixtures thereof; quaternary compounds selected from the group consisting of SnPbSSe, SnPbSeTe, SnPbSTe, and mixtures thereof; or any combination thereof. Group IV elements can be selected from the group consisting of Si, Ge, and mixtures thereof. Group IV compounds can be binary compounds selected from the group consisting of SiC, SiGe, and mixtures thereof.

[0229] Binary, ternary, or quaternary compounds may exist in the particles at a uniform concentration distribution, or they may exist in the particles at partially different concentration distributions. In embodiments, the quantum dots may have a core / shell structure in which one quantum dot surrounds another quantum dot. The core / shell structure may have a concentration gradient in which the concentration of the element present in the shell decreases towards the core.

[0230] In embodiments, quantum dots may have a core / shell structure comprising a core with nanocrystals as described above and a shell surrounding the core. The shell of the quantum dot may be a protective layer that prevents chemical deformation of the core to maintain its semiconductor properties and / or may be a charged layer that imparts electrophoretic properties to the quantum dot. The shell may be a single layer or may include multiple layers. Examples of shells for quantum dots may be metal oxides, non-metal oxides, semiconductor compounds, or combinations thereof.

[0231] For example, the metal oxide or non-metal oxide can be: binary compounds, such as SiO2, Al2O3, TiO2, ZnO, MnO, Mn2O3, Mn3O4, CuO, FeO, Fe2O3, Fe3O4, CoO, Co3O4, NiO; or ternary compounds, such as MgAl2O4, CoFe2O4, NiFe2O4 and CoMn2O4, but the examples are not limited thereto.

[0232] Examples of semiconductor compounds may include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AlSb, etc., but the embodiments are not limited thereto.

[0233] Quantum dots can have a full width at half maximum (FWHM) of an emission wavelength spectrum equal to or less than about 45 nm. For example, quantum dots can have an FWHM of an emission wavelength spectrum equal to or less than about 40 nm. For example, quantum dots can have an FWHM of an emission wavelength spectrum equal to or less than about 30 nm. Color purity or color reproducibility can be improved in the range mentioned above. Light emitted through quantum dots can be emitted in all directions, thus improving wide viewing angles.

[0234] There are no specific restrictions on the form of quantum dots, as long as it is a form commonly used in the field. For example, quantum dots can have spherical, pyramidal, multi-armed, or cubic shapes, or they can take the form of nanoparticles, nanotubes, nanowires, nanofibers, nanosheets, etc.

[0235] Quantum dots can control the color of emitted light based on their particle size; therefore, quantum dots can have a variety of light emission colors (such as blue, red, green, etc.).

[0236] exist Figures 3 to 6 In the light-emitting diode (ED) of the embodiment 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), but the embodiment is not limited thereto.

[0237] The electron transport region (ETR) can be a layer formed of a single material, a layer formed of different materials, or a multilayer structure with layers formed of different materials.

[0238] For example, the electron transport region (ETR) can have a single-layer structure of either the electron injection layer (EIL) or the electron transport layer (ETL), or it can have a single-layer structure formed of an electron injection material and an electron transport material. The ETR can have a single-layer structure formed of different materials, or it can have a structure in which the electron transport layer / electron injection layer (EIL), hole blocking layer (HBL) / electron transport layer / EIL / electron injection layer (EIL), or electron transport layer / buffer layer (not shown) / electron injection layer (EIL) are stacked from the emitter layer (EML) in their respective stated order, but the embodiments are not limited thereto. The ETR can have a thickness, for example, in the range of about 1000 Å to about 1500 Å.

[0239] Electron transport regions (ETRs) can be formed using various methods, such as vacuum deposition, spin coating, casting, Langmuir-Blodget (LB) method, inkjet printing, laser printing, laser-induced thermal imaging (LITI) method, etc.

[0240] The electron transport region (ETR) may include compounds represented by the formula ET-1 below.

[0241] [Formula ET-1]

[0242] In Equation ET-1, at least one of X1 to X3 can be N, and the rest of X1 to X3 can be C(R). a R a It can be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms. In formula ET-1, Ar1 to Ar3 can each be independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms.

[0243] In formula ET-1, a to c can each be an independent integer from 0 to 10. In formula ET-1, L1 to L3 can each be an independent, directly bonded, substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms. When a to c are 2 or greater, L1 to L3 can each be an independent, substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms.

[0244] The electron transport region (ETR) may include anthracene compounds. However, the embodiments are not limited thereto, and the ETR 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, 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-butyl Phenyl-1,2,4-triazole (TAZ), 4-(naphth-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(naphth-2-yl)anthracene (ADN), 1,3-bis[3,5-bis(pyridin-3-yl)phenyl]benzene (BmPyPhB), diphenyl(4-(triphenylsilyl)phenyl)phosphine oxide (TSPO1), or mixtures thereof.

[0245] The electron transport region (ETR) can include metal halides (such as LiF, NaCl, CsF, RbCl, RbI, CuI, and KI), lanthanides (such as Yb), or co-deposited materials of metal halides and lanthanides. For example, the ETR can include KI:Yb, RbI:Yb, etc., as co-deposited materials. The ETR can be formed using metal oxides such as Li₂O and BaO or lithium 8-hydroxyquinoline (Liq), but the embodiments are not limited thereto. The ETR can also be formed from a mixture of an electron transport material and an insulating organometallic salt. The organometallic salt can be a material having a band gap equal to or greater than about 4 eV. For example, the organometallic salt can include metal acetates, metal benzoates, metal acetoacetates, metal acetylacetonates, or metal stearates.

[0246] In addition to the materials described above, the electron transport region (ETR) may also include at least one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and 4,7-diphenyl-1,10-phenanthroline (Bphen), but the embodiments are not limited thereto.

[0247] The electron transport region (ETR) may include the compound of the electron transport region (ETR) described above in at least one of the electron injection layer (EIL), the electron transport layer (ETL), and the hole blocking layer (HBL).

[0248] When the electron transport region (ETR) includes an electron transport layer (ETL), the ETL can have a thickness in the range of about 100 Å to about 1000 Å. For example, the ETL can have a thickness in the range of about 150 Å to about 500 Å. When the thickness of the ETL meets the above range, satisfactory electron transport properties can be obtained without significantly increasing the driving voltage. When the ETR includes an electron injection layer (EIL), the EIL can have a thickness in the range of about 1 Å to about 100 Å. For example, the EIL can have a thickness in the range of about 3 Å to about 90 Å. When the thickness of the EIL meets the above range, satisfactory electron injection properties can be obtained without significantly increasing the driving voltage.

[0249] The second electrode EL2 is disposed on the electron transport region ETR. The second electrode EL2 can be a common electrode. The second electrode EL2 can be a cathode or an anode, but the embodiments are not limited thereto. For example, when the first electrode EL1 is an anode, the second electrode EL2 can be a cathode, and when the first electrode EL1 is a cathode, the second electrode EL2 can be an anode. The second electrode EL2 can include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, In, Sn, Zn, their oxides, their compounds, or mixtures thereof.

[0250] The second electrode EL2 can be a transmission electrode, a transmission-reflection electrode, or a reflection electrode. When the second electrode EL2 is a transmission electrode, it can be formed from a transparent metal oxide (e.g., indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), etc.).

[0251] When the second electrode EL2 is a transmissive or reflective electrode, it may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, compounds thereof, mixtures thereof (e.g., AgMg, AgYb, or MgYb), or materials having a multilayer structure comprising two or more of those selected from the above (such as LiF / Ca (e.g., a stacked structure of LiF and Ca) or LiF / Al (e.g., a stacked structure of LiF and Al)). In embodiments, the second electrode EL2 may have a multilayer structure comprising a reflective or transmissive film formed from the above materials and a transparent conductive film formed from indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), etc. For example, the second electrode EL2 may include the above-mentioned metallic materials, a combination of two or more metallic materials selected from the above-mentioned metallic materials, or oxides of the above-mentioned metallic materials.

[0252] Although not shown in the accompanying drawings, the second electrode EL2 can be electrically connected to the auxiliary electrode. When the second electrode EL2 is electrically connected to the auxiliary electrode, the resistance of the second electrode EL2 can be reduced.

[0253] In an embodiment, the light-emitting diode ED may further include a capping layer CPL disposed on the second electrode EL2. The capping layer CPL may be multilayer or a single layer.

[0254] In embodiments, the capping CPL may include an organic layer or an inorganic layer. For example, when 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, and SiN. xSiO y wait.

[0255] For example, when 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), etc., or may include epoxy resins or acrylates such as methacrylates. However, the embodiments are not limited thereto, and the capping CPL may include at least one of compounds P1 to P5 below.

[0256]

[0257]

[0258]

[0259]

[0260]

[0261] The capping layer CPL can have a refractive index equal to or greater than about 1.6. For example, the capping layer CPL can have a refractive index equal to or greater than about 1.6 relative to light in the wavelength range of about 550 nm to about 660 nm.

[0262] Figure 7 and Figure 8 All are schematic cross-sectional views of the display device DD according to the embodiments. Figure 7 It shows the corresponding Figure 1 A schematic cross-sectional view of the section along line I-I'. In the following text, with reference to... Figure 7 and Figure 8 In the description of the display device DD according to the embodiment, the description of the already described aspects will no longer be included. Figures 1 to 6 Explain the characteristics and describe the differences.

[0263] Reference Figure 7 According to an embodiment, the display device DD may include a display panel DP having a display element layer DP-ED, a light control layer CCL and a color filter layer CFL disposed on the display panel DP.

[0264] exist Figure 7 In the embodiment shown, the display panel DP may include a substrate layer BS, a circuit layer DP-CL disposed on the substrate layer BS, and a display element layer DP-ED, and the display element layer DP-ED may include a light-emitting diode ED.

[0265] A light-emitting diode (ED) may include a first electrode EL1, a hole transport region HTR disposed on the first electrode EL1, an emitter layer EML disposed on the hole transport region HTR, an electron transport region ETR disposed on the emitter layer EML, and a second electrode EL2 disposed on the electron transport region ETR. Figure 7 The structure of the light-emitting diode (ED) shown can be compared with that described above. Figures 3 to 6 The structure of the light-emitting diode (ED) is the same.

[0266] Reference Figure 7 The emitting layer EML can be disposed within the opening OH defined in the pixel defining layer PDL. For example, the emitting layer EML separated by the pixel defining layer PDL and disposed corresponding to each of the light-emitting regions PXA-R, PXA-G, and PXA-B can emit light within the same wavelength range. In the display device DD of the embodiment, the emitting layer EML can emit blue light. Although not shown in the figures, in the embodiment, the emitting layer EML can be disposed as a common layer covering the light-emitting regions PXA-R, PXA-G, and PXA-B.

[0267] At least one of the emission layers EMLs corresponding to the luminescent regions PXA-R, PXA-G, and PXA-B may include a polycyclic compound of the embodiment represented by Formula 1 described above, and the remaining emission layers EMLs may include additional fluorescent luminescent materials, phosphorescent luminescent materials, quantum dots, etc. However, the embodiments are not limited thereto.

[0268] A light control layer (CCL) can be disposed on a display panel (DP). The CCL may include a light converter. The light converter may include quantum dots or phosphors. The light converter can convert the wavelength of the supplied light and emit the converted light. For example, the CCL may be a layer containing quantum dots or phosphors.

[0269] The optical control layer (CCL) may include optical control units CCP1, CCP2, and CCP3. The optical control units CCP1, CCP2, and CCP3 may be spaced apart from each other.

[0270] Reference Figure 7 The segmented pattern BMP can be positioned between the spaced-apart optical control units CCP1, CCP2, and CCP3, but the embodiment is not limited to this. Figure 7 In the diagram, the segmentation pattern BMP is shown not to overlap with the optical control units CCP1, CCP2, and CCP3, but the edges of the optical control units CCP1, CCP2, and CCP3 may overlap with at least a portion of the segmentation pattern BMP.

[0271] The light control layer CCL may include a first light control unit CCP1, a second light control unit CCP2, and a third light control unit CCP3. The first light control unit CCP1 includes a first quantum dot QD1 that converts first-color light provided by a light-emitting diode ED into second-color light. The second light control unit CCP2 includes a second quantum dot QD2 that converts first-color light into third-color light. The third light control unit CCP3 transmits first-color light.

[0272] In an embodiment, the first light control unit CCP1 can provide red light as the second color light, and the second light control unit CCP2 can provide green light as the third color light. The third light control unit CCP3 can transmit and provide blue light as the first color light provided from the light-emitting diode ED. For example, the first quantum dot QD1 can be a red quantum dot, and the second quantum dot QD2 can be a green quantum dot. The same description provided above regarding quantum dots can be applied to quantum dots QD1 and QD2.

[0273] The optical control layer (CCL) may also include a scatterer (SP). The first optical control unit (CCP1) may include a first quantum dot (QD1) and a scatterer (SP), the second optical control unit (CCP2) may include a second quantum dot (QD2) and a scatterer (SP), and the third optical control unit (CCP3) may not include a quantum dot but may include a scatterer (SP).

[0274] The scatterer SP can be inorganic particles. For example, the scatterer SP can include at least one of TiO2, ZnO, Al2O3, SiO2, and hollow silica. The scatterer SP can include any one of TiO2, ZnO, Al2O3, SiO2, and hollow silica, or it can be a mixture of two or more materials selected from TiO2, ZnO, Al2O3, SiO2, and hollow silica.

[0275] The first optical control unit CCP1, the second optical control unit CCP2, and the third optical control unit CCP3 may each include matrix resins BR1, BR2, and BR3 in which quantum dots QD1 and QD2 and scatterers SP are dispersed. In an embodiment, the first optical control unit CCP1 may include the first quantum dots QD1 and scatterers SP dispersed in the first matrix resin BR1, the second optical control unit CCP2 may include the second quantum dots QD2 and scatterers SP dispersed in the second matrix resin BR2, and the third optical control unit CCP3 may include scatterers SP dispersed in the third matrix resin BR3. The matrix resins BR1, BR2, and BR3 may be media in which quantum dots QD1 and QD2 and scatterers SP are dispersed, and may be formed from various resin components commonly referred to as adhesives. For example, the matrix resins BR1, BR2, and BR3 may be acrylic resins, polyurethane resins, silicone resins, epoxy resins, etc. The matrix resins BR1, BR2, and BR3 may all be transparent resins. In the embodiments, the first matrix resin BR1, the second matrix resin BR2, and the third matrix resin BR3 may all be the same as or different from each other.

[0276] The light control layer CCL may include a barrier layer BFL1. The barrier layer BFL1 prevents the introduction of moisture and / or oxygen (hereinafter referred to as "moisture / oxygen"). The barrier layer BFL1 may be disposed on the light control units CCP1, CCP2, and CCP3 to prevent them from being exposed to moisture / oxygen. The barrier layer BFL1 may cover the light control units CCP1, CCP2, and CCP3. A barrier layer BFL2 may be disposed between the light control units CCP1, CCP2, and CCP3 and the color filter layer CFL. Figure 7 In this illustration, the blocking layer BFL2 is shown as part of the color filter layer CFL for ease of illustration; however, the embodiments of this disclosure are not limited thereto.

[0277] Barrier layers BFL1 and BFL2 may include at least one inorganic layer. For example, barrier layers BFL1 and BFL2 may be formed of inorganic materials. For instance, barrier layers BFL1 and BFL2 may be formed using materials including silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, hafnium nitride, tantalum nitride, silicon oxide, aluminum oxide, titanium oxide, tin oxide, cerium oxide, silicon oxynitride, or a metal thin film thereof that ensures light transmittance. Barrier layers BFL1 and BFL2 may also include organic films. Barrier layers BFL1 and BFL2 may be formed as a single layer or as multiple layers.

[0278] In the display device DD of this embodiment, the color filter layer CFL can be disposed on the light control layer CCL. For example, the color filter layer CFL can be directly disposed on the light control layer CCL. In this embodiment, the blocking layer BFL2 can be omitted.

[0279] The color filter layer CFL may include a light-blocking unit BM and filters CF1, CF2, and CF3. For example, the color filter layer CFL may include a first filter CF1 that transmits a second color of light, a second filter CF2 that transmits a third color of light, and a third filter CF3 that transmits a first color of light. For example, the first filter CF1 may be a red filter, the second filter CF2 may be a green filter, and the third filter CF3 may be a blue filter. Filters CF1, CF2, and CF3 may all include a polymerized photosensitive resin, a pigment, or a dye. The first filter CF1 may include a red pigment or a red dye, the second filter CF2 may include a green pigment or a green dye, and the third filter CF3 may include a blue pigment or a blue dye. However, the embodiments are not limited thereto, and the third filter CF3 may not include a pigment or dye. The third filter CF3 may include a polymerized photosensitive resin, but not a pigment or dye. The third filter CF3 may be transparent. The third filter CF3 may be formed of a transparent photosensitive resin.

[0280] In this embodiment, the first filter CF1 and the second filter CF2 can be yellow filters. The first filter CF1 and the second filter CF2 can be inseparable from each other and can be configured as a single unit.

[0281] The light-blocking unit BM can be a black matrix. The light-blocking unit BM can be formed by including organic or inorganic light-blocking materials, both of which include black pigments or dyes. The light-blocking unit BM can prevent light leakage and separate the boundaries between adjacent filters CF1, CF2, and CF3. In an embodiment, the light-blocking unit BM can be formed from a blue filter.

[0282] The first filter CF1, the second filter CF2, and the third filter CF3 can be set to correspond to the red emitting area PXA-R, the green emitting area PXA-G, and the blue emitting area PXA-B, respectively.

[0283] The substrate BL can be disposed on the color filter layer CFL. The substrate BL can provide a substrate surface on which the color filter layer CFL and the light control layer CCL are disposed. The substrate BL can be a glass substrate, a metal substrate, a plastic substrate, etc. However, the embodiments are not limited to these, and the substrate BL can include inorganic layers, organic layers, or composite material layers. Although not shown in the figures, the substrate BL may be omitted in the embodiments.

[0284] Figure 8 This is a schematic cross-sectional view showing a portion of the display device DD-TD according to an embodiment. Figure 8 It shows the corresponding Figure 7A schematic cross-sectional view of a portion of the display panel DP. In the display device DD-TD of the embodiment, the light-emitting diode ED-BT may include light-emitting structures OL-B1, OL-B2, and OL-B3. The light-emitting diode ED-BT may include a first electrode EL1 and a second electrode EL2 facing each other, and light-emitting structures OL-B1, OL-B2, and OL-B3 stacked between the first electrode EL1 and the second electrode EL2 in the thickness direction. The light-emitting structures OL-B1, OL-B2, and OL-B3 may each include an emissive layer EML (Emitting Layer). Figure 7 ) and an emission layer EML ( ) is disposed therebetween Figure 7 The hole transport region (HTR) and electron transport region (ETR) of the electron transport region.

[0285] For example, the light-emitting diode ED-BT included in the display device DD-TD of the embodiment may be a light-emitting diode having a series structure including multiple emission layers EML.

[0286] exist Figure 8 In the illustrated embodiment, the light emitted from each of the light-emitting structures OL-B1, OL-B2, and OL-B3 can be entirely blue light. However, the embodiment is not limited to this, and the wavelength ranges of the light emitted from each of the light-emitting structures OL-B1, OL-B2, and OL-B3 can be different from each other. For example, a light-emitting diode (ED-BT) comprising light-emitting structures OL-B1, OL-B2, and OL-B3 emitting light in different wavelength ranges can emit white light.

[0287] The charge generation layers CGL1 and CGL2 can be disposed between adjacent light-emitting structures OL-B1, OL-B2, and OL-B3. The charge generation layers CGL1 and CGL2 can each independently include a p-type charge generation layer and / or an n-type charge generation layer.

[0288] At least one of the light-emitting structures OL-B1, OL-B2, and OL-B3 included in the display device DD-TD of the embodiments may include the polycyclic compound of the embodiments described above.

[0289] The light-emitting diode ED-BT according to the embodiments may include the polycyclic compound of the embodiments described above in at least one emitter layer EML disposed between the first electrode EL1 and the second electrode EL2, and thus may exhibit improved luminous efficiency and lifetime characteristics.

[0290] The polycyclic compounds of the embodiments described above comprise a large portion such as a triterpenoid group or a carborane group as a linking group, and have a structure in which the polycyclic rings of two DABNA derivatives are linked by the linking group to prevent aggregation between the polycyclic compounds, and therefore exhibit excellent film properties when used as materials for light-emitting diodes. The polycyclic compounds of the embodiments can emit thermally activated delayed fluorescence, and when the polycyclic compounds of the embodiments are used as emission layer materials, the light-emitting diodes of the embodiments can exhibit excellent luminous efficiency and long lifetime characteristics.

[0291] The light-emitting diode of the embodiment may include a hole transport host, an electron transport host, an auxiliary dopant including an organometallic complex as a phosphorescent photosensitizer, and a light-emitting dopant of a polycyclic compound as described in the embodiment in the emission layer, so as to reduce energy loss in the triplet state and increase fluorescence emissivity, and thus exhibit improved luminous efficiency and long lifetime characteristics.

[0292] In the following description, embodiments of the polycyclic compound and the light-emitting diode will be described with reference to examples and comparative examples. The examples shown below are for illustrative purposes only and are not intended to limit the scope of the disclosure.

[0293] [Example] 1. Synthesis of polycyclic compounds The method for synthesizing polycyclic compounds according to the embodiments will be described in detail by providing methods for synthesizing compounds 1 to 6 as examples. The method for synthesizing polycyclic compounds, which will be described below, is provided as an example; therefore, the method for synthesizing polycyclic compounds according to the embodiments is not limited to the examples below.

[0294] Synthesis of Compound 1 Compound 1 according to the embodiments can be synthesized by, for example, the process described in reaction formula 1 below.

[0295] [Reaction Formula 1]

[0296] 10.8 g of intermediate compound 1-1 (40.0 mmol) and 22.5 g of intermediate compound 1-2 (80.0 mmol) were placed in a flask, and toluene was added. Sodium tert-butoxide, Pd2(dba)3, and tri-tert-butylphosphine tetrafluoroborate were added, and the mixture was refluxed for 6 hours. The residue obtained was purified by silica gel chromatography and recrystallized from it with a mixture of chloroform and hexane to give 21.0 g of intermediate compound 1-3 (yield: 78%).

[0297] 6.71 g of intermediate compounds 1-3 (10.0 mmol) and 3.92 g of boron triiodide (10.0 mmol) were placed in a flask, and 1,2-dichlorobenzene (o-DCB) was added. The residue was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 2.31 g of intermediate compounds 1-4 (yield: 34%).

[0298] 2.31 g of intermediate compounds 1-4 (3.40 mmol) and 0.58 g of intermediate compounds 1-5 (1.70 mmol) were placed in a flask, and a mixed solvent of toluene and EtOH was added. 0.3 M aqueous Na₂CO₃ solution and Pd(PPh₃)₄ bubbled under nitrogen for 10 min or longer were added, and the mixture was refluxed overnight. The residue was purified by silica gel chromatography and recrystallized from the residue with a mixed solvent of chloroform and hexane to give 2.10 g of compound 1 (yield: 80%). [MS: m / z [M]⁺ Calculated value 1539.94; Found value 1539.80] Synthesis of Compound 2 Compound 2 according to the embodiments can be synthesized, for example, by the process described in reaction formula 2 below.

[0299] [Reaction 2]

[0300] 10.8 g of intermediate compound 2-1 (40.0 mmol) and 25.7 g of intermediate compound 2-2 (80.0 mmol) were placed in a flask, and toluene was added. Sodium tert-butoxide, Pd2(dba)3, and tri-tert-butylphosphine tetrafluoroborate were added, and the mixture was refluxed for 6 hours. The residue obtained was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 22.3 g of intermediate compound 2-3 (yield: 74%).

[0301] 7.51 g of intermediate compound 2-3 (10.0 mmol) and 3.92 g of boron triiodide (10.0 mmol) were placed in a flask, and 1,2-dichlorobenzene (o-DCB) was added. The residue obtained was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 2.05 g of intermediate compound 2-4 (yield: 27%).

[0302] 3.04 g of intermediate compound 2-4 (4.00 mmol) and 0.68 g of intermediate compound 2-5 (2.00 mmol) were placed in a flask, and a mixed solvent of toluene and EtOH was added. 0.3 M Na₂CO₃ aqueous solution and Pd(PPh₃)₄ bubbled under nitrogen for 10 min or longer were added, and the mixture was refluxed overnight. The residue was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 2.31 g of compound 2 (yield: 68%). [MS: m / z [M]⁺ Calculated value 1699.69; Found value 1698.79] Synthesis of Compound 3 Compound 3 according to the embodiments can be synthesized, for example, by the process described in reaction formula 3 below.

[0303] [Reaction 3]

[0304] 10.8 g of intermediate compound 3-1 (40.0 mmol) and 13.5 g of intermediate compound 3-2 (80.0 mmol) were placed in a flask and toluene was added. Sodium tert-butoxide, Pd2(dba)3, and tri-tert-butylphosphine tetrafluoroborate were added, and the mixture was refluxed for 6 hours. The residue obtained was purified by silica gel chromatography and recrystallized from it with a mixture of chloroform and hexane to give 13.8 g of intermediate compound 3-3 (yield: 77%).

[0305] 6.70 g of intermediate compound 3-3 (15.0 mmol) and 5.87 g of boron triiodide (15.0 mmol) were placed in a flask, and 1,2-dichlorobenzene (o-DCB) was added. The residue was purified by silica gel chromatography and recrystallized from it with a mixture of chloroform and hexane to give 2.59 g of intermediate compound 3-4 (yield: 38%).

[0306] 1.64 g of intermediate compound 3-4 (3.60 mmol) and 0.62 g of intermediate compound 3-5 (1.80 mmol) were placed in a flask, and a mixed solvent of toluene and EtOH was added. 0.3 M aqueous Na₂CO₃ solution and Pd(PPh₃)₄ bubbled under nitrogen for 10 min or longer were added, and the mixture was refluxed overnight. The residue was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 1.43 g of compound 3 (yield: 73%). [MS: m / z [M]⁺ Calculated value 1090.44; Found value 1090.40] Synthesis of Compound 4 Compound 4 according to the embodiments can be synthesized by, for example, the process described in reaction formula 4 below.

[0307] [Reaction 4]

[0308] 15.7 g of intermediate compound 4-1 (50.0 mmol) and 28.1 g of intermediate compound 4-2 (100.0 mmol) were placed in a flask, and toluene was added. Sodium tert-butoxide, Pd2(dba)3, and tri-tert-butylphosphine tetrafluoroborate were added, and the mixture was stirred at 80 °C for 6 hours. The residue obtained was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 14.3 g of intermediate compound 4-3 (yield: 40%).

[0309] 14.0 g of intermediate compound 4-3 (19.6 mmol) and 7.67 g of boron triiodide (19.6 mmol) were placed in a flask, and 1,2-dichlorobenzene (o-DCB) was added. The residue was purified by silica gel chromatography and recrystallized from it with a mixture of chloroform and hexane to give 1.42 g of intermediate compound 4-4 (yield: 10%).

[0310] 7.24 g of intermediate compound 4-4 (10.0 mmol) was placed in a flask and THF was added. CuI, Pd(PPh3)4, 1.96 g of trimethylsilylacetylene (TMSA, 20.0 mmol) and Et3N were added, and the mixture was stirred at 60 °C for 24 hours. The residue obtained was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 4.38 g of intermediate compound 4-5 (yield: 58%).

[0311] 22.7 g of intermediate compound 4-5 (30.0 mmol) was placed in a flask, and THF, methanol, and 1 MkOH aqueous solution were added. The mixture was stirred at room temperature for 1 hour. The residue was purified by silica gel chromatography and recrystallized from it with a mixture of chloroform and hexane to give 2.41 g of intermediate compound 4-6 (yield: 12%).

[0312] 2.27 g of intermediate compound 4-6 (3.40 mmol) was placed in a flask and THF was added. 2.46 g of intermediate compound 4-4 (3.40 mmol) was then added, along with methanol and a 1 M KOH aqueous solution. The mixture was stirred at 60 °C for 24 hours. The residue was purified by silica gel chromatography to obtain 0.27 g of intermediate compound 4-7 (yield: 6%).

[0313] 0.026 g of decborane (0.21 mmol) and N,N-dimethylaniline were added to a flask containing toluene, and the mixture was stirred at room temperature for 30 minutes and then at 100 °C for 2 hours. The temperature was lowered to room temperature, and 0.27 g of intermediate compound 4-7 (0.21 mmol) was added, followed by reflux for 16 hours. The residue was purified by silica gel chromatography to give 0.10 g of compound 4 (yield: 48%). [MS: m / z [M]+ Calculated value 1430.03] Synthesis of Compound 5 Compound 5 according to the embodiments can be synthesized, for example, by the process described in reaction formula 5 below.

[0314] [Reaction 5]

[0315] 15.7 g of intermediate compound 5-1 (50.0 mmol) and 32.1 g of intermediate compound 5-2 (100.0 mmol) were placed in a flask, and toluene was added. Sodium tert-butoxide, Pd2(dba)3, and tri-tert-butylphosphine tetrafluoroborate were added, and the mixture was stirred at 80 °C for 6 hours. The residue obtained was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 13.9 g of intermediate compound 5-3 (yield: 35%).

[0316] 13.9 g of intermediate compound 5-3 (17.5 mmol) and 6.85 g of boron triiodide (17.5 mmol) were placed in a flask, and 1,2-dichlorobenzene (o-DCB) was added. The residue was purified by silica gel chromatography and recrystallized from it with a mixture of chloroform and hexane to give 0.99 g of intermediate compound 5-4 (yield: 7%).

[0317] 8.04 g of intermediate compound 5-4 (10.0 mmol) was placed in a flask and THF was added. CuI, Pd(PPh3)4, 1.96 g of trimethylsilylacetylene (TMSA, 20.0 mmol), and Et3N were then added, and the mixture was stirred at 60 °C for 24 hours. The residue was purified by silica gel chromatography and recrystallized from it using a mixture of chloroform and hexane to give 5.18 g of intermediate compound 5-5 (yield: 62%).

[0318] 25.1 g of intermediate compound 5-5 (30.0 mmol) was placed in a flask, and THF, methanol, and 1 MkOH aqueous solution were added. The mixture was stirred at room temperature for 1 hour. The residue obtained was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 2.03 g of intermediate compound 5-6 (yield: 9%).

[0319] 1.87 g of intermediate compound 5-6 (2.50 mmol) was placed in a flask and THF was added. 2.01 g of intermediate compound 5-4 (2.50 mmol) was added, along with methanol and 1 M KOH aqueous solution. The mixture was stirred at 60 °C for 24 hours. The residue was purified by silica gel chromatography to obtain 0.29 g of intermediate compound 5-7 (yield: 8%).

[0320] 0.03 g of decborane (0.25 mmol) and N,N-dimethylaniline were added to a flask containing toluene, and the mixture was stirred at room temperature for 30 minutes and then at 100 °C for 2 hours. The temperature was lowered to room temperature, and 0.20 g of intermediate compound 5-7 (0.25 mmol) was added, followed by reflux for 16 hours. The residue was purified by silica gel chromatography to give 0.18 g of compound 5 (yield: 45%). [MS: m / z [M]+ Calculated value 1589.78] Synthesis of Compound 6 Compound 6 according to the embodiments can be synthesized by, for example, the process described in reaction formula 6 below.

[0321] [Reaction Formula 6]

[0322] 15.7 g of intermediate compound 6-1 (50.0 mmol) and 16.9 g of intermediate compound 6-2 (100.0 mmol) were placed in a flask, and toluene was added. Sodium tert-butoxide, Pd2(dba)3, and tri-tert-butylphosphine tetrafluoroborate were added, and the mixture was stirred at 80 °C for 6 hours. The residue obtained was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 7.87 g of intermediate compound 6-3 (yield: 32%).

[0323] 7.86 g of intermediate compound 6-3 (16.0 mmol) and 6.26 g of boron triiodide (16.0 mmol) were placed in a flask, and 1,2-dichlorobenzene (o-DCB) was added. The residue was purified by silica gel chromatography and recrystallized from it with a mixture of chloroform and hexane to give 0.4 g of intermediate compound 6-4 (yield: 5%).

[0324] 3.00 g of intermediate compound 6-4 (6.00 mmol) was placed in a flask and THF was added. CuI, Pd(PPh3)4, 1.18 g of trimethylsilylacetylene (TMSA, 12.0 mmol) and Et3N were added, and the mixture was stirred at 60 °C for 24 hours. The residue obtained was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 2.07 g of intermediate compound 6-5 (yield: 65%).

[0325] 15.9 g of intermediate compound 6-5 (30.0 mmol) was placed in a flask, and THF, methanol, and 1 M KOH aqueous solution were added. The mixture was stirred at room temperature for 1 hour. The residue obtained was purified by silica gel chromatography and recrystallized from it with a mixed solvent of chloroform and hexane to give 1.60 g of intermediate compound 6-6 (yield: 12%).

[0326] 1.60 g of intermediate compound 6-6 (3.60 mmol) was placed in a flask and THF was added. 1.80 g of intermediate compound 6-4 (3.60 mmol) was then added, along with methanol and a 1 M KOH aqueous solution. The mixture was stirred at 60 °C for 24 hours. The residue was purified by silica gel chromatography to obtain 0.22 g of intermediate compound 6-7 (yield: 7%).

[0327] 0.034 g of decborane (0.28 mmol) and N,N-dimethylaniline were added to a flask containing toluene, and the mixture was stirred at room temperature for 30 minutes and then at 100 °C for 2 hours. The temperature was lowered to room temperature, and 0.22 g of intermediate compound 6-7 (0.25 mmol) was added, followed by reflux for 16 hours. The residue was purified by silica gel chromatography to give 0.11 g of compound 6 (yield: 42%). [MS: m / z [M]+ Calculated value 979.53] 2. Fabrication and Evaluation of Light Emitting Diodes (Manufacturing of light-emitting diodes) The following method is used to fabricate light-emitting diodes containing the polycyclic compounds of the embodiments in the emission layer. The light-emitting diodes of Examples 1 to 4 are fabricated using the polycyclic compounds 1 to 4 described above as light-emitting dopants in the emission layer.

[0328] In Comparative Example 1 and Comparative Example 2, comparative example compound C1 and comparative example compound C2 were used as light-emitting dopants in the emission layer to fabricate light-emitting diodes, respectively.

[0329] Comparative example compounds used to manufacture light-emitting diodes are shown below.

[0330] (Comparative example compounds)

[0331] (Other compounds used in the manufacture of light-emitting diodes)

[0332]

[0333] A patterned ITO glass substrate is cleaned, and an NPD is deposited at a thickness of 300 Å to form a hole injection layer. A TCTA is deposited at a thickness of 200 Å to form a hole transport layer. CzSi is vacuum deposited on the hole transport layer to form an auxiliary emitter layer with a thickness of 100 Å.

[0334] A first host, a second host, an auxiliary dopant, and a luminescent dopant were co-deposited in a weight ratio of 70:30:15:0.5 to form an emission layer with a thickness of 250 Å. In the comparative example and the example, compound HT-08 was used as the first host, compound ET-04 as the second host, and compound 13 as the auxiliary dopant when forming the emission layer. The compounds in the comparative example and the example were used as luminescent dopants.

[0335] TSPO1 was deposited with a thickness of 200 Å to form an electron transport layer, TPBi was deposited with a thickness of 300 Å to form a buffer layer, and LiF was deposited with a thickness of 10 Å to form an electron injection layer.

[0336] Al is provided at a thickness of 3000 Å to form the second electrode.

[0337] (Evaluation of the properties of light-emitting diodes) Table 1 shows the evaluation results of the light-emitting diodes of Examples 1 to 4, as well as Comparative Examples 1 and 2. Table 1 compares and illustrates the luminous efficiency, emission wavelength, and diode lifetime of the manufactured light-emitting diodes. (At 10 mA / cm²...) 2 The luminous efficiency values ​​at the given current densities are presented in Table 1, showing the performance evaluation results for the example and comparative examples. Diode lifetime is expressed in 10 mA / cm². 2 The reduction time from initial brightness to 95% brightness (brightness decrease of 5%) under continuous drive at a current density.

[0338] The current density, drive voltage, and luminous efficiency of the example and comparative examples of LEDs were measured in a darkroom using a 2400 Series source instrument (Keithley Instruments), a CS-200 colorimeter (Konica Minolta, Inc.), and the PC program LabVIEW 2.0 (Japan National Instruments Corporation).

[0339] [Table 1]

[0340] Referring to the results in Table 1, it can be seen that the example and comparative example LEDs emit blue light with emission wavelengths ranging from 461 nm to 462 nm. Referring to the results in Table 1, compared to the comparative example LEDs, the example LEDs using the polycyclic compound of the embodiment as the luminescent dopant material for the emission layer exhibit superior luminous efficiency and improved diode lifetime characteristics.

[0341] Referring to Table 1, it is confirmed that Examples 1 to 4 comprise polycyclic compounds having dimer structures linked by large linking groups, and therefore, compared with the light-emitting dopants used in the emitting layers of the light-emitting diodes of Comparative Examples 1 and 2, Examples 1 to 4 exhibit long lifetime and high efficiency characteristics.

[0342] The polycyclic compound according to the embodiments has a dimer-type compound structure linked by a large linking group and is used as a delayed fluorescence emitting material, thereby contributing to the high efficiency and long lifetime characteristics of light-emitting diodes. The light-emitting diode according to the embodiments comprises the polycyclic compound according to the embodiments and therefore can exhibit long lifetime and high efficiency characteristics.

[0343] The light-emitting diodes according to the embodiments include the polycyclic compounds of the embodiments, and therefore can exhibit high efficiency and long lifespan characteristics.

[0344] Embodiments have been disclosed herein, and although terminology has been used, it is used and will be interpreted in a general and descriptive sense only, and not for limiting purposes. In some instances, as will be apparent to those skilled in the art, features, characteristics, and / or elements described in connection with the embodiments may be used alone or in combination with features, characteristics, and / or elements described in connection with other embodiments, unless otherwise specifically indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the spirit and scope of the disclosure set forth in the claims.

Claims

1. A light-emitting diode, the light-emitting diode comprising: First electrode; The second electrode is disposed on the first electrode; as well as An emission layer is disposed between the first electrode and the second electrode, wherein, Both the first electrode and the second electrode independently comprise Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, In, Sn, Zn, their oxides, their compounds, or mixtures thereof, and The emission layer comprises a polycyclic compound represented by Formula 1: [Formula 1] ， In Equation 1, X1 to X4 are all independently B(R) a ), N(R b ), C(R c (R) d ), O, S or Se, a to d are all independent integers from 0 to 4. R a To R d R1 through R4 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms. L is a substituted or unsubstituted divalent triterpenoid group or a substituted or unsubstituted divalent carborane alkyl group.

2. The light-emitting diode according to claim 1, wherein, The polycyclic compound represented by Formula 1 is represented by Formula 1-1: [Equation 1-1] ， In Equation 1-1, X1 to X4, a to d, R1 to R4 and L are all the same as those defined in Equation 1.

3. The light-emitting diode according to claim 1, wherein, L is a group represented by one of L-1 to L-4: ， Among them, in L-1 to L-4, " "It's BH," " It is C, and * indicates a bonding site with a neighboring atom.

4. The light-emitting diode according to claim 1, wherein, R1 through R4 are each independently tert-butyl, substituted or unsubstituted phenyl, or substituted or unsubstituted biphenyl.

5. The light-emitting diode according to claim 1, wherein, X1 through X4 are the same.

6. The light-emitting diode according to claim 1, wherein, The emission layer is a delayed fluorescence emission layer comprising a host and dopants, and The dopant includes the polycyclic compound.

7. The light-emitting diode according to claim 1, wherein, The polycyclic compound represented by Formula 1 is selected from one of the compounds in group 1: [Compound Group 1] ， Among them, compounds 4 to 6, CB is a divalent carbon boron alkyl group.

8. The light-emitting diode according to claim 1, wherein, The emission layer includes: First subject; The second entity is different from the first entity; Auxiliary dopants, including organometallic complexes; and Luminescent dopants, The luminescent dopant includes the polycyclic compound.

9. The light-emitting diode according to claim 8, wherein, The first subject comprises one selected from compounds HT-01 to HT-09: 。 10. The light-emitting diode according to claim 8, wherein, The second body comprises one selected from compounds ET-01 to ET-06: 。 11. The light-emitting diode according to claim 8, wherein, The auxiliary dopant includes at least one selected from the group P of compounds: [Compound Group P] 。 12. The light-emitting diode according to claim 1, wherein, The emitting layer emits blue light with a center wavelength in the range of 450 nm to 470 nm.

13. The light-emitting diode according to claim 1, wherein the light-emitting diode further comprises a capping layer disposed on the second electrode, wherein, The refractive index of the capping layer is equal to or greater than 1.

6.

14. A light-emitting diode, the light-emitting diode comprising: First electrode; The second electrode is disposed on the first electrode; as well as An emission layer is disposed between the first electrode and the second electrode, wherein, The emitting layer includes: a first hole transport entity; a second electron transport entity, different from the first hole transport entity; an auxiliary dopant; and a luminescent dopant, different from the auxiliary dopant, and The luminescent dopant is a polycyclic compound represented by Formula 1: [Formula 1] ， In Equation 1, X1 to X4 are all independently B(R) a ), N(R b ), C(R c (R) d ), O, S or Se, a to d are all independent integers from 0 to 4. R a To R d R1 through R4 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 cyclic carbon atoms. L is a substituted or unsubstituted divalent triterpenoid group or a substituted or unsubstituted divalent carborane alkyl group.

15. The light-emitting diode according to claim 14, wherein, The polycyclic compound represented by Formula 1 is represented by Formula 1-1: [Equation 1-1] ， In Equation 1-1, X1 to X4, a to d, R1 to R4 and L are all the same as those defined in Equation 1.

16. The light-emitting diode according to claim 14, wherein, L is a group represented by one of L-1 to L-4: ， Among them, in L-1 to L-4, " "It's BH," " It is C, and * indicates a bonding site with a neighboring atom.

17. The light-emitting diode according to claim 14, wherein, The polycyclic compound represented by Formula 1 is selected from one of the compounds in group 1: [Compound Group 1] ， Among them, compounds 4 to 6, CB is a divalent carbon boron alkyl group.

18. The light-emitting diode according to claim 14, wherein, The first host for hole transport includes one selected from compounds HT-01 to HT-09: 。 19. The light-emitting diode according to claim 14, wherein, The second electron transport entity includes one selected from compounds ET-01 to ET-06: 。 20. The light-emitting diode according to claim 14, wherein, The auxiliary dopant includes at least one selected from the group P of compounds: [Compound Group P] 。

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