Light-emitting element

Abstract

To provide a light-emitting element with excellent luminous efficiency and long life characteristic.SOLUTION: A light-emitting element includes a first electrode, a second electrode, and a light-emitting layer disposed between the first electrode and the second electrode and containing a polycyclic compound represented by the following chemical formula. The first electrode and the second electrode independently contain at least one selected from Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, In, Sn, and Zn, a compound of two or more kinds selected from these, a mixture of two or more kinds selected from these, or an oxide of any of these.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a light-emitting element, and more specifically, to a light-emitting element comprising a novel polycyclic compound in the light-emitting layer. [Background technology]

[0002] Recently, there has been a lot of development going on in the field of video display devices, such as organic electroluminescence display devices. Organic electroluminescence display devices are display devices that include so-called self-emissive light-emitting elements that achieve display by recombining holes and electrons injected from the first and second electrodes in the light-emitting layer, causing the light-emitting material in the light-emitting layer to emit light.

[0003] Applying light-emitting elements to display devices requires lower drive voltages, higher luminous efficiency, and longer lifespans, and there is a constant need for the development of light-emitting element materials that can stably achieve these requirements.

[0004] In particular, in recent years, technologies have been developed for phosphorescence, which utilizes the energy of the triplet state, and for delayed fluorescence emission, which utilizes the phenomenon of triplet exciton collisions generating singlet excitons (Triplet-triplet annihilation, TTA), in order to realize highly efficient light-emitting devices. Development is also underway for thermally activated delayed fluorescence (TADF) materials that utilize the delayed fluorescence phenomenon. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Korean Patent Application Publication No. 10-2020-0062329A [Patent Document 2] Korean Patent Publication No. 10-1707799B1 [Patent Document 3] Korean Patent Publication No. 10-1482559B1

Summary of the Invention

Problems to be Solved by the Invention

[0006] An object of the present invention is to provide a light-emitting element exhibiting excellent luminous efficiency and long-life characteristics.

Means for Solving the Problems

[0007]

[0008] One embodiment includes a first electrode, a second electrode disposed on the first electrode, and a light-emitting layer disposed between the first electrode and the second electrode and containing a polycyclic compound represented by the following Chemical Formula 1. The first electrode and the second electrode each independently include at least one selected from Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, In, Sn, and Zn, two or more compounds selected from these, two or more mixtures selected from these, or oxides of these, and provides a light-emitting element.

[0008]

Chem.

[0009] In Chemical Formula 1, X1 to X4 are each independently BR a , NR b , CR c R d , O, S, or Se, and a to d are each independently an integer of 0 or more and 4 or less. R a to R d , and R1 to 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 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, and L is a substituted or unsubstituted divalent triphenylene group or a substituted or unsubstituted divalent carboranylene group.

[0010] ​​Chemical formula 1 is represented by the following chemical formula 1-1.

[0011] [ka] (Chemical formula 1-1)

[0012] In chemical formula 1-1, X1-X4, a-d, R1-R4, and L are as defined in chemical formula 1.

[0013] L is represented by one of the following L-1 to L-4.

[0014] [ka]

[0015] JPEG0007910907000004.jpg4108

[0016] R1 and R4 are, independently, a t-butyl group, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted biphenylyl group.

[0017] X1 to X4 are the same.

[0018] The light-emitting layer is a delayed fluorescence light-emitting layer containing a host and a dopant, and the dopant contains a polycyclic compound.

[0019] Chemical formula 1 is represented by one of the polycyclic compounds in the following Group 1 of compounds.

[0020] [First compound group] [ka] [ka]

[0021] In compounds 4 to 6, "CB" represents a divalent carboranylene group.

[0022] The luminescent layer comprises a first host, a second host different from the first host, an auxiliary dopant containing an organometallic complex, and a luminescent dopant, the luminescent dopant containing a polycyclic compound.

[0023] The first host contains at least one of the following HT-01 to HT-09 compounds.

[0024] [ka] [ka] [ka]

[0025] The second host contains at least one of the following compounds ET-01 to ET-06.

[0026] [ka]

[0027] The auxiliary dopant contains at least one compound from the following compound group P.

[0028] [Compound group P] [ka] [ka] [ka] [ka]

[0029] The light-emitting layer emits blue light with a central wavelength of 450 nm or more and 470 nm or less.

[0030] It further includes a capping layer disposed on the second electrode, and the refractive index of the capping layer is 1.6 or more.

[0031] One embodiment includes a first electrode, a second electrode disposed on the first electrode, and a light-emitting layer disposed between the first electrode and the second electrode, the light-emitting layer including a hole-transporting first host, an electron-transporting second host different from the first host, an auxiliary dopant, and a light-emitting dopant different from the auxiliary dopant, and the light-emitting dopant is represented by the following Chemical Formula 1.

[0032]

Chemical Formula

[0033] In Chemical Formula 1, X1 to X4 are each independently BR a , NR b , CR c R d , O, S, or Se, and a to d are each independently an integer of 0 or more and 4 or less. R a ~R d , and R1 to 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 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, and L is a substituted or unsubstituted divalent triphenylenylene group or a substituted or unsubstituted divalent carboranylene group.

Advantages of the Invention

[0034] The light-emitting device of one embodiment exhibits high efficiency and long-life characteristics by including the polycyclic compound of one embodiment.

Brief Description of the Drawings

[0035] [Figure 1] This is a plan view showing a display device according to one embodiment. [Figure 2] This is a cross-sectional view of a display device according to one embodiment. [Figure 3] This is a schematic cross-sectional view showing a light-emitting element according to one embodiment. [Figure 4] This is a schematic cross-sectional view showing a light-emitting element according to one embodiment. [Figure 5] This is a schematic cross-sectional view showing a light-emitting element according to one embodiment. [Figure 6] This is a schematic cross-sectional view showing a light-emitting element according to one embodiment. [Figure 7] This is a cross-sectional view of a display device according to one embodiment. [Figure 8] This is a cross-sectional view of a display device according to one embodiment. [Modes for carrying out the invention]

[0036] Because the present invention can be modified in various ways and take on various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, this should not be understood as limiting the present invention to any particular disclosure, but rather as including all modifications, equivalents, or substitutes that fall within the spirit and technical scope of the present invention.

[0037] In describing each drawing, similar reference numerals are used for similar components. In the attached drawings, the dimensions of structures are shown enlarged for clarity of the invention. Terms such as "first," "second," etc., are used to describe various components, but components are not limited to terms. Terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the invention, the first component may be named the second component, and similarly, the second component may also be named the first component. A singular expression includes plural expressions unless the context clearly indicates otherwise.

[0038] In this application, terms such as “includes” or “having” should be understood to indicate the presence of features, figures, steps, actions, components, parts, or combinations thereof described in the specification, without prejudice to the presence or possibility of adding one or more other features, figures, steps, actions, components, parts, or combinations thereof.

[0039] In this application, when a part such as a layer, film, region, or plate is said to be "above" or "above" another part, this includes not only when it is "directly above" another part, but also when there is another part in between. Conversely, when a part such as a layer, film, region, or plate is said to be "below" or "below" another part, this includes not only when it is "directly below" another part, but also when there is another part in between. Furthermore, in this application, "positioned above" includes not only when it is positioned above, but also when it is positioned below.

[0040] In this specification, "substituted or unsubstituted" means substituted or unsubstituted with one or more substituents selected from the group consisting of deuterium atoms, halogen atoms, cyano groups, nitro groups, amino groups, silyl groups, oxy groups, thio groups, sulfinyl groups, sulfonyl groups, carbonyl groups, boron groups, phosphine oxide groups, phosphine sulfide groups, alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, hydrocarbon ring groups, aryl groups, and heterocyclic groups. Furthermore, each of the substituents exemplified above may or may not be substituted. For example, a biphenylyl group may be interpreted as an aryl group, or as a phenyl group substituted with a phenyl group.

[0041] In this specification, "bonding with adjacent groups to form a ring" means bonding with adjacent groups to form a substituted or unsubstituted hydrocarbon ring, or a substituted or unsubstituted heterocycle. Hydrocarbon rings include aliphatic hydrocarbon rings and aromatic hydrocarbon rings. Heterocycles include aliphatic heterocycles and aromatic heterocycles. Hydrocarbon rings and heterocycles are monocyclic or polycyclic. Furthermore, rings formed by bonding with each other may bond with other rings to form a spirostructure.

[0042] In this specification, "adjacent group" means a substituent substituted on an atom directly bonded to the atom to which the substituent is substituted, another substituent substituted on the atom to which the substituent is substituted, or the substituent that is most stereostructically adjacent to the substituent in question. For example, the two methyl groups in 1,2-dimethylbenzene are interpreted as "adjacent groups," and the two ethyl groups in 1,1-diethylcyclopentane are interpreted as "adjacent groups." Similarly, the two methyl groups in 4,5-dimethylphenanthrene are interpreted as "adjacent groups."

[0043] In this specification, examples of halogen atoms include fluorine, chlorine, bromine, or iodine atoms.

[0044] In this specification, alkyl groups are linear, branched, or cyclic. The number of carbon atoms in an alkyl group is 1 to 50, 1 to 30, 1 to 20, 1 to 10, or 1 to 6. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, s-butyl, t-butyl, i-butyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, i-pentyl, neopentyl, t-pentyl, cyclopentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, and 2-ethylpentyl. hexyl group, 2-butylhexyl group, cyclohexyl group, 4-methylcyclohexyl group, 4-t-butylcyclohexyl group, n-heptyl group, 1-methylpeptyl group, 2,2-dimethylheptyl group, 2-ethylheptyl group, 2-butylheptyl group, n-octyl group, t-octyl group, 2-ethyloctyl group, 2-butyloctyl group, 2-hexyloctyl group, 3,7-dimethyloctyl group, cyclooctyl group, n-nonyl group, n-decyl group, ada Mantyl group, 2-ethyldecyl group, 2-butyldecyl group, 2-hexyldecyl group, 2-octyldecyl group, n-undecyl group, n-dodecyl group, 2-ethyldodecyl group, 2-butyldodecyl group, 2-hexyldodecyl group, 2-octyldecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, 2-ethylhexadecyl group, 2-butylhexadecyl group, 2-hexylhexadecyl group, 2-octylhexadecyl Examples of n-Icosyl groups include, but are not limited to, n-heptadecyl group, n-octadecyl group, n-nonadecyl group, n-icosyl group, 2-ethylicosyl group, 2-butylicosyl group, 2-hexylicosyl group, 2-octylicosyl group, n-henicosyl group, n-docosyl group, n-tricosyl group, n-tetracosyl group, n-pentacosyl group, n-hexacosyl group, n-heptacosyl group, n-octacosyl group, n-nonacosyl group, and n-triacontyl group.

[0045] In this specification, a hydrocarbon ring group means any active group or substituent derived from an aliphatic hydrocarbon ring. A hydrocarbon ring group is a saturated hydrocarbon ring group having 5 to 20 carbon atoms.

[0046] In this specification, an aryl group means any active group or substituent derived from an aromatic hydrocarbon ring. The aryl group is either a monocyclic aryl group or a polycyclic aryl group. The number of ring-forming carbon atoms in the aryl group is 6 to 30, 6 to 20, or 6 to 15. Examples of aryl groups include, but are not limited to, phenyl, naphthyl, fluorenyl, anthracenyl, phenanthryl, biphenylyl, terphenylyl, quarterphenylyl, quincphenylyl, sexiphenylyl, triphenylenyl, pyrenyl, benzofluorantenyl, and crisenyl groups.

[0047] In this specification, the fluorenyl group may be substituted, or two substituents may be bonded to each other to form a spiro structure. Examples of substitutions of the fluorenyl group are as follows, but are not limited to these.

[0048] [ka] [ka] [ka] [ka]

[0049] In this specification, a heterocyclic group means any working group or substituent derived from a ring containing one or more heteroatoms from B, O, N, P, Si, and S. Heterocyclic groups include aliphatic heterocyclic groups and aromatic heterocyclic groups. Aromatic heterocyclic groups may also be heteroaryl groups. Aliphatic heterocyclics and aromatic heterocyclics may be monocyclic and polycyclic.

[0050] In this specification, a heterocyclic group contains one or more heteroatoms from B, O, N, P, Si, and S. If a heterocyclic group contains two or more heteroatoms, the two or more heteroatoms may be the same or different. A heterocyclic group may be a monocyclic heterocyclic group or a polycyclic heterocyclic group, and is a concept that includes a heteroaryl group. The number of ring-forming carbon atoms in a heterocyclic group is 2 to 30, 2 to 20, or 2 to 10.

[0051] In this specification, an aliphatic heterocyclic group contains one or more heteroatoms from B, O, N, P, Si, and S. The number of ring-forming carbon atoms of the aliphatic heterocyclic group is 2 to 30, 2 to 20, or 2 to 10. Examples of aliphatic heterocyclic groups include, but are not limited to, oxyranyl group, thyranyl group, pyrrolidinyl group, piperidinyl group, tetrahydrofuranyl group, tetrahydrothiophenyl group, thianyl group, tetrahydropyranyl group, and 1,4-dioxanyl group.

[0052] In this specification, a heteroaryl group contains one or more heteroatoms from B, O, N, P, Si, and S. If a heteroaryl group contains two or more heteroatoms, the two or more heteroatoms may be the same or different. A heteroaryl group is either a monocyclic heterocyclic group or a polycyclic heterocyclic group. The number of ring-forming carbon atoms in a heteroaryl group is 2 to 30, 2 to 20, or 2 to 10. Examples of heteroaryl groups include thiophenyl group, furanyl group, pyrrolyl group, imidazolyl group, triazolyl group, pyridinyl group, bipyridinyl group, pyrimidinyl group, triazinyl group, triazolyl group, acridinyl group, pyridadinyl group, quinolinyl group, quinazolinyl group, quinoxalinyl group, phenoxadinyl group, phthalazinyl group, pyridopyrimidinyl group, pyridopyradinyl group, pyrazinopyradinyl group, isoquinolinyl group, indolyl group, carbazolyl group, N-arylcarbazolyl group, N Examples include, but are not limited to, heteroarylcarbazolyl groups, N-alkylcarbazolyl groups, benzoxazolyl groups, benzimidazolyl groups, benzothiazolyl groups, benzocarbazolyl groups, benzothiophenyl groups, dibenzothiophenyl groups, thienothiophenyl groups, benzofuranyl groups, phenanthrolinyl groups, thiazolyl groups, isoxazolyl groups, oxazolyl groups, oxadiazolyl groups, thiadiazolyl groups, phenothiazinyl groups, dibenzosilolyl groups, and dibenzofuranyl groups.

[0053] In this specification, the above-described description of aryl groups applies to arylene groups, except that they are divalent. The above-described description of heteroaryl groups applies to heteroarylene groups, except that they are divalent.

[0054] In this specification, the silyl group includes alkylsilyl groups and arylsilyl groups. Examples of silyl groups include, but are not limited to, trimethylsilyl, triethylsilyl, t-butyldimethylsilyl, vinyldimethylsilyl, propyldimethylsilyl, triphenylsilyl, diphenylsilyl, and phenylsilyl groups.

[0055] In this specification, the number of carbon atoms in the amino group is not particularly limited, but may be between 1 and 30. The amino group includes alkylamino groups, arylamino groups, or heteroarylamino groups. Examples of amino groups include, but are not limited to, methylamino groups, dimethylamino groups, phenylamino groups, diphenylamino groups, naphthylamino groups, and 9-methyl-anthracenylamino groups.

[0056] In this specification, the number of carbon atoms in the carbonyl group is not particularly limited, but may be between 1 and 40, between 1 and 30, or between 1 and 20. For example, it may have, but is not limited to, the following structure.

[0057] [ka]

[0058] In this specification, the number of carbon atoms in the sulfinyl group and the sulfonyl group is not particularly limited, but may be between 1 and 30. The sulfinyl group includes alkylsulfinyl groups and arylsulfinyl groups. The sulfonyl group includes alkylsulfonyl groups and arylsulfonyl groups.

[0059] In this specification, the term "thio group" includes alkylthio groups and arylthio groups. A thio group means a group to which a sulfur atom is bonded, in the manner defined above, either an alkyl group or an aryl group. Examples of thio groups include, but are not limited to, methylthio groups, ethylthio groups, propylthio groups, pentylthio groups, hexylthio groups, octylthio groups, dodecylthio groups, cyclopentylthio groups, cyclohexylthio groups, phenylthio groups, and naphthylthio groups.

[0060] In this specification, an oxy group means a group in which an oxygen atom is bonded to an alkyl group or aryl group as defined above. Oxy groups include alkoxy groups and aryl groups. Alkoxy groups are linear, branched, or cyclic. The number of carbon atoms in an alkoxy group is not particularly limited, but may be, for example, 1 to 20 or 1 to 10. Examples of oxy groups include, but are not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, butoxy, pentyloxy, hexyloxy, octyloxy, nonyloxy, decyloxy, and benzyloxy groups.

[0061] In this specification, a boron group means a group in which a boron atom is bonded to an alkyl or aryl group as defined above. A boron group includes alkylboron groups and arylboron groups. Examples of boron groups include, but are not limited to, trimethylboron, triethylboron, t-butyldimethylboron, triphenylboron, diphenylboron, and phenylboron.

[0062] In this specification, the alkenyl group may be a straight chain or a branched chain. The number of carbon atoms is not particularly limited, but may be 2 to 30, 2 to 20, or 2 to 10. Examples of alkenyl groups include, but are not limited to, vinyl groups, 1-butenyl groups, 1-pentenyl groups, 1,3-butadienylaryl groups, styrenyl groups, and styrylvinyl groups.

[0063] In this specification, the number of carbon atoms in the amino group is not particularly limited, but may be between 1 and 30. The amino group includes alkylamino groups and arylamino groups. Examples of amino groups include, but are not limited to, methylamino groups, dimethylamino groups, phenylamino groups, diphenylamino groups, naphthylamino groups, and 9-methyl-anthracenylamino groups.

[0064] In this specification, among alkylthio groups, alkylsulfoxy groups, alkylaryl groups, alkylamino groups, alkylboron groups, alkylsilyl groups, and alkylamino groups, alkyl groups are as exemplified by the alkyl groups described above.

[0065] In this specification, among the aryloxy group, arylthio group, arylsulfoxy group, arylamino group, arylboron group, arylsilyl group, and arylamino group, the aryl group is as described above.

[0066] In this specification, direct linkage may mean a single linkage.

[0067] TIFF0007910907000021.tif17170

[0068] One embodiment of the present invention will be described below with reference to the drawings.

[0069] Figure 1 is a plan view showing one embodiment of the display device DD. Figure 2 is a cross-sectional view of the display device DD according to one embodiment. Figure 2 is a cross-sectional view showing the portion corresponding to the line I-I' in Figure 1.

[0070] The display device DD includes a display panel DP and an optical layer PP disposed on the display panel DP. The display panel DP includes light-emitting elements ED-1, ED-2, and ED-3. The display device DD includes a plurality of light-emitting elements ED-1, ED-2, and ED-3. The optical layer PP is disposed on the display panel DP and controls the reflected light from the display panel DP due to external light. The optical layer PP may include, for example, a polarizing layer or a color filter layer. On the other hand, contrary to the figures, the optical layer PP may be omitted from the display device DD of one embodiment.

[0071] A base substrate BL is placed on top of the optical layer PP. The base substrate BL is a component that provides the base surface on which the optical layer PP is placed. The base substrate BL may be a glass substrate, a metal substrate, a plastic substrate, etc. However, the embodiment is not limited to these, and the base substrate BL may be an inorganic layer, an organic layer, or a composite material layer. Also, contrary to the figures, in one embodiment the base substrate BL may be omitted.

[0072] A display device DD according to one embodiment further includes a packing layer (not shown). The packing layer (not shown) is disposed between the display element layer DP-ED and the base substrate BL. The packing layer (not shown) is an organic material layer. The packing layer (not shown) includes at least one of an acrylic resin, a silicone resin, and an epoxy resin.

[0073] The display panel DP includes a base layer BS, a circuit layer DP-CL provided on the base layer BS, and a display element layer DP-ED. The display element layer DP-ED includes a pixel definition film PDL, light-emitting elements ED-1, ED-2, and ED-3 positioned between the pixel definition films PDL, and a sealing layer TFE positioned on top of the light-emitting elements ED-1, ED-2, and ED-3.

[0074] The base layer BS is a component that provides the base surface on which the display element layer DP-ED is arranged. The base layer BS may be a glass substrate, a metal substrate, a plastic substrate, etc. However, the embodiment is not limited to these, and the base layer BS may be an inorganic layer, an organic layer, or a composite material layer.

[0075] In one embodiment, the circuit layer DP-CL is located on the base layer BS, but the circuit layer DP-CL includes a plurality of transistors (not shown). Each transistor (not shown) includes a control electrode, an input electrode, and an output electrode. For example, the circuit layer DP-CL may include switching transistors and drive transistors for driving light-emitting elements ED-1, ED-2, and ED-3.

[0076] Each of the light-emitting elements ED-1, ED-2, and ED-3 has the structure of one embodiment of the light-emitting element ED as shown in Figures 3 to 6, which will be described later. Each of the light-emitting elements ED-1, ED-2, and ED-3 includes a first electrode EL1, a hole transport region HTR, light-emitting layers EML-R, EML-G, EML-B, an electron transport region ETR, and a second electrode EL2.

[0077] Figure 2 shows an embodiment in which the light-emitting layers EML-R, EML-G, and EML-B of the light-emitting elements ED-1, ED-2, and ED-3 are arranged within the opening OH defined in the pixel-defining film PDL, and the hole transport region HTR, electron transport region ETR, and second electrode EL2 are provided as a common layer for all light-emitting elements ED-1, ED-2, and ED-3. However, the embodiment is not limited to this, and in one embodiment, contrary to the illustration in Figure 2, the hole transport region HTR and electron transport region ETR may be provided by patterning inside the opening OH defined in the pixel-defining film PDL. For example, in one embodiment, the hole transport region HTR, light-emitting layers EML-R, EML-G, EML-B, and electron transport region ETR of the light-emitting elements ED-1, ED-2, and ED-3 may be provided by patterning using an inkjet printing method.

[0078] The sealing layer TFE covers the light-emitting elements ED-1, ED-2, and ED-3. The sealing layer TFE seals the display element layer DP-ED. The sealing layer TFE is a thin-film sealing layer. The sealing layer TFE consists of one or more layers stacked together. The sealing layer TFE includes at least one insulating layer. In one embodiment, the sealing layer TFE includes at least one inorganic film (hereinafter referred to as the sealing inorganic film). In another embodiment, the sealing layer TFE includes at least one organic film (hereinafter referred to as the sealing organic film) and at least one sealing inorganic film.

[0079] The encapsulating inorganic film protects the display element layer DP-ED from moisture / oxygen, and the encapsulating organic film protects the display element layer DP-ED from foreign matter such as dust particles. The encapsulating inorganic film may contain, but is not limited to, silicon nitride, silicon oxide, titanium oxide, or aluminum oxide. The encapsulating organic film may contain, but is not limited to, acrylic compounds or epoxy compounds. The encapsulating organic film may contain, but is not limited to, photopolymerizable organic materials.

[0080] The sealing layer TFE is placed on the second electrode EL2 and positioned to fill the opening OH.

[0081] Referring to Figures 1 and 2, the display device DD includes a non-emitting region NPXA and emitting regions PXA-R, PXA-G, and PXA-B. Each of the emitting regions PXA-R, PXA-G, and PXA-B is a region from which light generated by the light-emitting elements ED-1, ED-2, and ED-3, respectively, is emitted. The emitting regions PXA-R, PXA-G, and PXA-B are spaced apart from each other on a plane.

[0082] The light-emitting regions PXA-R, PXA-G, and PXA-B are regions separated by the pixel definition film PDL. The non-light-emitting region NPXA is the region between adjacent light-emitting regions PXA-R, PXA-G, and PXA-B, and corresponds to the pixel definition film PDL. On the other hand, in this specification, the light-emitting regions PXA-R, PXA-G, and PXA-B each correspond to a pixel. The pixel definition film PDL separates the light-emitting elements ED-1, ED-2, and ED-3. The light-emitting layers EML-R, EML-G, and EML-B of the light-emitting elements ED-1, ED-2, and ED-3 are separated by being located in the aperture OH defined in the pixel definition film PDL.

[0083] The light-emitting regions PXA-R, PXA-G, and PXA-B are divided into multiple groups according to the color of the light generated from the light-emitting elements ED-1, ED-2, and ED-3. The display device DD of one embodiment shown in Figures 1 and 2 exemplifies three light-emitting regions PXA-R, PXA-G, and PXA-B that emit red light, green light, and blue light, respectively. For example, the display device DD of one embodiment may include a red light-emitting region PXA-R, a green light-emitting region PXA-G, and a blue light-emitting region PXA-B that are separated from each other.

[0084] In one embodiment of the display device DD, the multiple light-emitting elements ED-1, ED-2, and ED-3 emit light of different wavelengths from each other. For example, in one embodiment, the display device DD may include a light-emitting element ED-1 that emits red light, a second light-emitting element ED-3 that emits green light, and a third light-emitting element ED-3 that emits blue light. In other words, the red light-emitting region PXA-R, the green light-emitting region PXA-G, and the blue light-emitting region PXA-B of the display device DD correspond to the first light-emitting element ED-1, the second light-emitting element ED-2, and the third light-emitting element ED-3, respectively.

[0085] However, the embodiments are not limited to these, and the first to third light-emitting elements ED-1, ED-2, and ED-3 may emit light in the same wavelength range, or at least one of them may emit light in a different wavelength range. Furthermore, all of the first to third light-emitting elements ED-1, ED-2, and ED-3 may emit blue light.

[0086] In one embodiment of the display device DD, the light-emitting regions PXA-R, PXA-G, and PXA-B are arranged in a striped pattern. Referring to Figure 1, multiple red light-emitting regions PXA-R, multiple green light-emitting regions PXA-G, and multiple blue light-emitting regions PXA-B are aligned along the second directional axis DR2. In addition, the red light-emitting regions PXA-R, green light-emitting regions PXA-G, and blue light-emitting regions PXA-B are arranged alternately along the first directional axis DR1.

[0087] In Figures 1 and 2, the areas of the light-emitting regions PXA-R, PXA-G, and PXA-B are shown to be similar, but the embodiments are not limited to this, and the areas of the light-emitting regions PXA-R, PXA-G, and PXA-B may differ from each other depending on the wavelength range of the emitted light. On the other hand, the areas of the light-emitting regions PXA-R, PXA-G, and PXA-B refer to the area as viewed from the plane defined by the first directional axis DR1 and the second directional axis DR2.

[0088] On the other hand, the arrangement of the light-emitting regions PXA-R, PXA-G, and PXA-B is not limited to that shown in Figure 1. The order in which the red light-emitting region PXA-R, the green light-emitting region PXA-G, and the blue light-emitting region PXA-B are arranged can be provided in various combinations depending on the display quality characteristics required by the display device DD. For example, the arrangement of the light-emitting regions PXA-R, PXA-G, and PXA-B may be a pentile arrangement or a diamond arrangement.

[0089] Furthermore, the areas of the light-emitting regions PXA-R, PXA-G, and PXA-B are different from each other. For example, in one embodiment, the area of ​​the green light-emitting region PXA-G may be smaller than the area of ​​the blue light-emitting region PXA-B, but the embodiment is not limited to this.

[0090] Figures 3 to 6 below are schematic cross-sectional views showing a light-emitting element according to one embodiment. The light-emitting element ED according to one embodiment includes 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 includes sequentially stacked hole transport region HTR, light-emitting layer EML, and electron transport region ETR. In other words, the light-emitting element ED according to one embodiment includes sequentially stacked first electrode EL1, hole transport region HTR, light-emitting layer EML, electron transport region ETR, and second electrode EL2.

[0091] Figure 4 shows a cross-sectional view of a light-emitting element ED in one embodiment, in which 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, compared to Figure 3. Figure 5 also shows a cross-sectional view of a light-emitting element ED in one embodiment, in which the hole transport region HTR includes a hole injection layer HIL, a hole transport layer HTL, and an electron blocking layer EBL, compared to Figure 3, and the electron transport region ETR includes an electron injection layer EIL, an electron transport layer ETL, and a hole blocking layer HBL. Figure 6 shows a cross-sectional view of a light-emitting element ED in one embodiment, in which a capping layer CPL is placed on the second electrode EL2, compared to Figure 4.

[0092] In one embodiment, the light-emitting element ED contains the polycyclic compound of the embodiment described later in the light-emitting layer EML. On the other hand, in one embodiment, the display device DD (Figure 2) containing multiple light-emitting regions contains the polycyclic compound of the embodiment described later in the light-emitting layer EML constituting at least one of the light-emitting regions.

[0093] In one embodiment of a light-emitting element ED, the first electrode EL1 is conductive. The first electrode EL1 is made of a metallic material, a metal alloy, or a conductive compound. The first electrode EL1 is either an anode or a cathode. However, the embodiment is not limited to this. The first electrode EL1 is also a pixel electrode. The first electrode EL1 is a transmissive electrode, a semitransmissive electrode, or a reflective electrode. The first electrode EL1 includes at least one selected from Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, In, Sn, and Zn, two or more compounds selected from these, a mixture of two or more selected from these, or oxides thereof.

[0094] When the first electrode EL1 is a transmissive electrode, the first electrode EL1 includes a transparent metal oxide, such as ITO (indium tin oxide), IZO (indium zinc oxide), ZnO (zinc oxide), ITZO (indium tin zinc oxide), etc. When the first electrode EL1 is a semi-transmissive or reflective electrode, the first electrode EL1 includes Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca (a layered structure of LiF and Ca), LiF / Al (a layered structure of LiF and Al), Mo, Ti, W, or compounds or mixtures thereof (for example, a mixture of Ag and Mg). Alternatively, the first electrode EL1 is a multi-layer structure including a reflective film or semi-transmissive film made of the above materials, and a transparent conductive film made of ITO, IZO, ZnO, ITZO, etc. For example, the first electrode EL1 may have a three-layer structure of ITO / Ag / ITO, but is not limited to this. Furthermore, the embodiments are not limited to this, and the first electrode EL1 may include the above-mentioned metal material, a combination of two or more metal materials selected from the above-mentioned metal materials, or an oxide of the above-mentioned metal material. The thickness of the first electrode EL1 is approximately 70 nm to approximately 1000 nm. For example, the thickness of the first electrode EL1 may be approximately 100 nm to approximately 300 nm.

[0095] The hole transport region (HTR) is provided on the first electrode EL1. The hole transport region (HTR) includes at least one of a hole injection layer (HIL), a hole transport layer (HTL), a buffer layer or luminescence auxiliary layer (not shown), and an electron blocking layer (EBL). The thickness of the hole transport region (HTR) may be, for example, about 5 nm to about 1500 nm.

[0096] The hole transport region (HTR) may have a single layer made of a single material, a single layer made of multiple different materials, or a multilayer structure having multiple layers made of multiple different materials.

[0097] For example, the hole transport region HTR may have a single-layer structure of a hole injection layer HIL or a hole transport layer HTL, or it may have a single-layer structure consisting of a hole injection material and a hole transport material. Furthermore, the hole transport region HTR may have a single-layer structure consisting of multiple different materials, or it may have a structure of a hole injection layer HIL / hole transport layer HTL, a hole injection layer HIL / hole transport layer HTL / buffer layer (not shown), a hole injection layer HIL / buffer layer (not shown), a hole transport layer HTL / buffer layer (not shown), or a hole injection layer HIL / hole transport layer HTL / electron blocking layer EBL stacked sequentially from the first electrode EL1, but the embodiments are not limited to these.

[0098] Hole transport regions (HTRs) are formed using a variety of methods, including vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) method, inkjet printing, laser printing, and laser-induced thermal imaging (LITI).

[0099] The hole transport region (HTR) includes compounds represented by the chemical formula H-1 below.

[0100] [ka] (Chemical formula H-1)

[0101] In chemical formula H-1, L1 and L2 are independently directly bonded, substituted, or unsubstituted arylene groups with 6 to 30 ring-forming carbon atoms, or substituted or unsubstituted heteroarylene groups with 2 to 30 ring-forming carbon atoms. a and b are independently integers between 0 and 10. On the other hand, when a or b is an integer of 2 or more, multiple L1 and L2 are independently substituted or unsubstituted arylene groups with 6 to 30 ring-forming carbon atoms, or substituted or unsubstituted heteroarylene groups with 2 to 30 ring-forming carbon atoms.

[0102] In chemical formula H-1, Ar1 to Ar2 are each independently substituted or unsubstituted aryl groups with 6 to 30 ring-forming carbon atoms, or substituted or unsubstituted heteroaryl groups with 2 to 30 ring-forming carbon atoms. Furthermore, in chemical formula H-1, Ar3 is a substituted or unsubstituted aryl group with 6 to 30 ring-forming carbon atoms.

[0103] The compound represented by the chemical formula H-1 is a monoamine compound. Alternatively, the compound represented by the chemical formula H-1 is Ar -1 The compound is a diamine compound in which at least one of ~Ar3 contains an amino group as a substituent. Alternatively, the compound represented by the chemical formula H-1 is a carbazole compound containing a substituted or unsubstituted carbazolyl group in at least one of Ar1 to Ar2, or a fluorene compound containing a substituted or unsubstituted fluorenyl group in at least one of Ar1 to Ar2.

[0104] A compound represented by the chemical formula H-1 is represented by any one of the compounds in compound group H below. However, the compounds listed in compound group H below are illustrative examples, and the compound represented by the chemical formula H-1 is not limited to those shown in compound group H below.

[0105] [Compound group H] [ka] [ka] [ka] [ka] [ka]

[0106] The hole transport region (HTR) is used for phthalocyanine compounds such as copper phthalocyanine, and DNTPD(N 1 ,N 1’ -([1,1'-biphenyl]-4,4'-diyl)bis(N 1 -phenyl-N 4 ,N 4 -di-m-tolylbenzene-1,4-diamine), m-MTDATA(4,4',4”-[tris(3-methylphenyl)phenylamino)triphenylamine], TDATA(4,4',4”-tris(N,N-diphenylamino)triphenylamine), 2-TNATA(4,4',4”-tris[N-(2-naphthyl)-N-phenylamino]-triphenylamine), PEDOT / PSS(poly(3,4-ethylenedioxythiophene) / poly(4-styrene sulfonate), PANI / DBSA(polyaniline / dodecylbenzenesulfonic acid), PANI / It may also contain CSA (polyaniline / camphor sulfonic acid), PANI / PSS ((polyaniline) / poly(4-styrene sulfonate)), NPB (or NPD) (N,N'-di(naphthalene-1-yl)-N,N'-diphenyl-benzidine), polyether ketone containing triphenylamine (TPAPEK), 4-isopropyl-4'-methyldiphenyliodonium [tetrakis(pentafluorophenyl) borate], HATCN (dipyradino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonitride), etc.

[0107] The hole transport region HTR may also include carbazole derivatives such as N-phenylcarbazole and polyvinylcarbazole, fluorene derivatives, triphenylamine derivatives such as TPD (N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine) and TCTA (4,4',4"-tris(N-carbazolyl)triphenylamine), NPB (N,N'-di(naphthalene-1-yl)-N,N'-diphenyl-benzidine), TAPC (4,4'-cyclohexylidenebis[N,N-bis(4-methylphenyl)benzeneamine]), HMTPD (4,4'-bis[N,N'-(3-tolyl)amino]-3,3'-dimethylbiphenyl), and mCP (1,3-bis(N-carbazolyl)benzene).

[0108] Furthermore, the hole transport region (HTR) includes CzSi(9-(4-tert-butylphenyl)-3,6-bis(triphenylsilyl)-9H-carbazole), CCP(9-phenyl-9H-3,9'-bicarbazole), or mDCP(1,3-bis(1,8-dimethyl-9H-carbazole-9-yl)benzene).

[0109] The hole transport region HTR comprises the hole transport region compound described above, and at least one of the hole injection layer HIL, hole transport layer HTL, and electron blocking layer EBL.

[0110] The thickness of the hole transport region (HTR) may be approximately 10 nm to 1000 nm, for example, approximately 10 nm to 500 nm. If the hole transport region (HTR) includes a hole injection layer (HIL), the thickness of the HIL is, for example, approximately 3 nm to 100 nm. If the hole transport region (HTR) includes a hole transport layer (HTL), the thickness of the HTL is approximately 3 nm to 100 nm. For example, if the hole transport region (HTR) includes an electron blocking layer (EBL), the thickness of the EBL is, for example, approximately 1 nm to 100 nm. When the thicknesses of the hole transport region (HTR), hole injection layer (HIL), hole transport layer (HTL), and electron blocking layer (EBL) satisfy the above-described ranges, sufficient hole transport characteristics can be obtained without a substantial increase in the driving voltage.

[0111] The hole transport region (HTR) further includes, in addition to the substances described above, charge-generating materials to improve conductivity. The charge-generating materials are uniformly or non-uniformly dispersed within the hole transport region (HTR). The charge-generating materials are, for example, p-dopant. The p-dopant may, but is not limited to, include at least one of metal halide compounds, quinone derivatives, metal oxides, and cyano group-containing compounds. For example, p-dopants include metal halide compounds such as CuI and RbI, quinone derivatives such as TCNQ (tetracyanoquinodimethane) and F4-TCNQ (2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane), metal oxides such as tungsten oxide and molybdenum oxide, and cyano group-containing compounds such as HATCN (dipyradino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonnitrile) and NDP9 (4-[[2,3-bis[cyano-(4-cyano-2,3,5,6-tetrafluorophenyl)methylidene]cyclopropylidene]-cyanomethyl]-2,3,5,6-tetrafluorobenzonitrile), but the embodiments are not limited to these.

[0112] As described above, the hole transport region (HTR) further includes at least one of a buffer layer (not shown) and an electron blocking layer (EBL), in addition to the hole transport layer (HTL) and the hole injection layer (HIL). The buffer layer (not shown) compensates for the resonance distance due to the wavelength of light emitted from the light emission layer (EML) and increases the luminescence efficiency. The material included in the buffer layer (not shown) is a material that can be included in the hole transport region (HTR). The electron blocking layer (EBL) is a layer that prevents electron injection from the electron transport region (ETR) to the hole transport region (HTR).

[0113] The emissive layer (EML) is provided on top of the hole transport region (HTR). The emissive layer (EML) has a thickness of, for example, about 10 nm to about 100 nm, or about 10 nm to about 30 nm. The emissive layer (EML) has a multilayer structure consisting of a single layer made of a single material, a single layer made of multiple different materials, or multiple layers made of multiple different materials.

[0114] One embodiment of the light-emitting element ED includes the polycyclic compound of one embodiment in the light-emitting layer EML. The polycyclic compound of one embodiment is represented by the following chemical formula 1.

[0115] [ka] (chemical formula 1)

[0116] In chemical formula 1, X1 to X4 are each independently BR a , NR b , CR c R d It is O, S, or Se. Also, in chemical formula 1, R a ~R d Each of these is 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 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

[0117] For example, in one embodiment, X1 to X4 may all be the same. However, the embodiment is not limited to this, and at least one may differ from the others.

[0118] In one embodiment, R a ~R d This may be a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenylyl group, etc. However, the embodiments are not limited to these.

[0119] In chemical formula 1, a to d are each independent integers between 0 and 4, and R1 to R4 are each independent hydrogen atom, deuterium atom, halogen atom, substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

[0120] When a to d are integers greater than or equal to 1, for example, R1 and R4 are each independently a t-butyl group, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted biphenylyl group. However, the embodiments are not limited to these.

[0121] In chemical formula 1, L is a substituted or unsubstituted divalent triptycenyl-ene, or a substituted or unsubstituted divalent carboranyl-ene. For example, L may be an unsubstituted divalent triptycenyl-ene group or an unsubstituted carboranyl-ene group.

[0122] In chemical formula 1, L is represented by one of the following formulas L-1 to L-4.

[0123] [ka]

[0124] TIFF0007910907000030.tif36170

[0125] In other words, the polycyclic compound of one embodiment has a dimer-like compound skeletal structure linked by a bulky linker. The polycyclic compound of one embodiment has a structure in which two DABNA derivatives containing boron (B) atoms are linked by a linker. In one embodiment, the two DABNA derivatives linked by the linker are symmetrical with respect to the linker. However, the embodiments are not limited to this.

[0126] In one embodiment, a polycyclic compound in a dimerized form linked by a linker suppresses aggregation between adjacent polycyclic compounds, improving film formation quality when forming the organic layer of a light-emitting device. Furthermore, the polycyclic compound of one embodiment is used as an auxiliary dopant or similar energy transfer agent, increasing Forster energy transfer and suppressing Dexter energy transfer, thereby increasing the device lifetime and improving the efficiency of a light-emitting device that includes the polycyclic compound of one embodiment in its light-emitting layer.

[0127] A polycyclic compound of one embodiment represented by chemical formula 1 is represented by the following chemical formula 1-1.

[0128] [ka] (Chemical formula 1-1)

[0129] In the above chemical formula 1-1, the same provisions as those described for chemical formula 1 above apply to X1-X4, a-d, R1-R4, and L. In other words, the polycyclic compound of one embodiment contains divalent triptysenylene and divalent carboranylene as linkers, and they are linked to each other by linkers at the para position opposite the B atom of the polycyclic derivative called the DABNA derivative. The two DABNA derivatives linked by the linker L have the same structure. However, the embodiments are not limited to this.

[0130] The polycyclic compound of one embodiment represented by chemical formula 1 is represented by any one of the compounds in the following first group of compounds. The light-emitting element ED of one embodiment contains at least one of the polycyclic compounds in the following first group of compounds in the light-emitting layer EML.

[0131] [First compound group] [ka] [ka]

[0132] In compounds 4 to 6 of the first compound group, "CB" represents a divalent carboranylene group. For example, in chemical formulas 4 to 6, "CB" is represented by one of the L-2 to L-4 structures described above. More specifically, in chemical formulas 4 to 6, "CB" has the L-3 structure described above.

[0133] The polycyclic compound of one embodiment, represented by chemical formula 1, can be used as a fluorescent material or a thermally activated delayed fluorescence (TADF) material. For example, the polycyclic compound of one embodiment may be used as a light-emitting dopant that emits blue light. Alternatively, the polycyclic compound of one embodiment can be used as a TADF dopant material.

[0134] One embodiment of the polycyclic compound has an emission center wavelength (λ) in the wavelength region of 490 nm or less. max The material is a light-emitting material having ). For example, the polycyclic compound of one embodiment represented by chemical formula 1 may be a light-emitting material having a center emission wavelength in the wavelength region of 450 nm to 470 nm. In other words, the polycyclic compound of one embodiment is a blue thermally activated delayed fluorescence dopant. However, the embodiments are not limited to this.

[0135] In the light-emitting element ED of one embodiment shown in Figures 3 to 6, the light-emitting layer EML includes a host and a dopant, but the light-emitting layer EML includes the polycyclic compound of the above embodiment as a dopant.

[0136] In one embodiment of the light-emitting element ED, the light-emitting layer EML includes a first host, a second host, an auxiliary dopant, and a light-emitting dopant. In one embodiment, the first host and the second host are different from each other. The auxiliary dopant includes an organometallic compound. The light-emitting dopant is the polycyclic compound of one embodiment represented by chemical formula 1 described above.

[0137] In one embodiment, the first host is a hole-transporting host, and the second host is an electron-transporting host. In one embodiment, the light-emitting element ED contains at least one compound from HT-01 to HT-09 as the first host in the light-emitting layer EML.

[0138] [ka] [ka] [ka]

[0139] Furthermore, in one embodiment, the light-emitting element ED includes at least one compound from ET-01 to ET-06 below as a second host in the light-emitting layer EML.

[0140] [ka]

[0141] In one embodiment of the light-emitting element ED, the light-emitting layer EML contains an organometallic complex. For example, in one embodiment of the light-emitting element ED, the light-emitting layer EML may contain an organometallic complex as an auxiliary dopant. In one embodiment, the auxiliary dopant contained in the light-emitting layer EML is called a phosphorescent sensor. In one embodiment of the light-emitting element ED, the phosphorescent sensor contained in the light-emitting layer EML transfers energy to the light-emitting dopant, increasing the proportion of light emitted by the light-emitting dopant through fluorescence emission.

[0142] In the light-emitting element ED, the light-emitting layer EML contains at least one compound from the following compound group P as an auxiliary dopant.

[0143] [Compound group P] [ka] [ka] [ka] [ka]

[0144] However, the embodiments are not limited to these, and the light-emitting element ED of one embodiment may include a known phosphorescent dopant material of organometallic complex as an auxiliary dopant.

[0145] In one embodiment, the light-emitting element ED includes the first and second hosts described above, an organometallic complex auxiliary dopant, and a light-emitting dopant containing the polycyclic compound of the above embodiment in the light-emitting layer EML, thereby exhibiting excellent device lifetime and improved luminous efficiency characteristics.

[0146] One embodiment of the light-emitting element ED further comprises the following light-emitting layer material in addition to the polycyclic compound of the embodiment described above, the first and second hosts described above, and the auxiliary dopant material. In one embodiment of the light-emitting element ED, the light-emitting layer EML includes an anthracene derivative, a pyrene derivative, a fluorantene derivative, a chrysene derivative, a dihydrobenzanthracene derivative, or a triphenylene derivative. Specifically, the light-emitting layer EML may include an anthracene derivative or a pyrene derivative.

[0147] In one embodiment of the light-emitting element ED shown in Figures 3 to 6, the light-emitting layer EML contains a host and a dopant, but the light-emitting layer EML contains a compound represented by the following chemical formula E-1. The compound represented by the following chemical formula E-1 is used as a fluorescent host material.

[0148] [ka] (Chemical formula E-1)

[0149] In chemical formula E-1, R 31 ~R 40 Each of these groups is independently 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 ring-forming aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted ring-forming heteroaryl group having 2 to 30 carbon atoms, or is bonded to an adjacent group to form a ring. On the other hand, R 31 ~R 40 These groups bond with adjacent groups to form saturated hydrocarbon rings, unsaturated hydrocarbon rings, saturated heterocycles, or unsaturated heterocycles.

[0150] In chemical formula E-1, c and d are each independent integers between 0 and 5 (inclusive).

[0151] Chemical formula E-1 is represented by one of the following compounds E1 to E19.

[0152] [ka] [ka] [ka] [ka] [ka] [ka] [ka]

[0153] In one embodiment, the light-emitting layer EML contains a compound represented by the following chemical formula E-2a or E-2b. The compound represented by the following chemical formula E-2a or E-2b is used as a phosphorescent host material. [ka] (Chemical formula E-2a)

[0154] In chemical formula E-2a, a is an integer between 0 and 10, and L a is a directly bonded, substituted, or unsubstituted ring-forming arylene group with 6 to 30 carbon atoms, or a substituted or unsubstituted ring-forming heteroarylene group with 2 to 30 carbon atoms. On the other hand, if a is an integer of 2 or more, multiple L a Each of these is independently a substituted or unsubstituted arylene group with 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group with 2 to 30 ring-forming carbon atoms.

[0155] In chemical formula E-2a, A1 to A5 are each independently either N or CR. i R a ~R i Each of these groups is 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 ring-forming aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted ring-forming heteroaryl group having 2 to 30 carbon atoms, or is bonded to an adjacent group to form a ring. a ~R i These groups bond with adjacent groups to form a hydrocarbon ring or a heterocycle containing N, O, S, etc., as ring-forming atoms.

[0156] On the other hand, in chemical formula E-2a, two or three selected from A1 to A5 are N and the rest are CR. i That is the case.

[0157] [ka] (Chemical formula E-2b)

[0158] In the chemical formula E-2b, Cbz1 and Cbz2 are each independently an unsubstituted carbazolyl group or a carbazolyl group substituted with an aryl group having 6 to 30 ring-forming carbon atoms. b is a directly bonded, substituted, or unsubstituted ring-forming arylene group with 6 to 30 carbon atoms, or a substituted or unsubstituted ring-forming heteroarylene group with 2 to 30 carbon atoms. On the other hand, b is an integer between 0 and 10, and if b is an integer of 2 or more, multiple L b Each of these is independently a substituted or unsubstituted arylene group with 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group with 2 to 30 ring-forming carbon atoms.

[0159] The compound represented by chemical formula E-2a and the compound represented by E-2b are each represented by one of the compounds in compound group E-2 below. However, the compounds listed in compound group E-2 below are illustrative examples, and the compounds represented by chemical formula E-2a or chemical formula E-2b are not limited to those shown in compound group E-2 below.

[0160] [Compound group E-2] [ka] [ka] [ka] [ka]

[0161] The luminescent layer EML further comprises a host material that is a common material known in the relevant art. For example, the luminescent layer EML may contain at least one of the following as the host material: DPEPO (bis[2-(diphenylphosphino)phenyl] ether oxide), CBP (4,4'-bis(N-carbazolyl)-1,1'-biphenyl), mCP (1,3-bis(carbazole-9-yl)benzene), PPF (2,8-bis(diphenylphosphoryl)dibenzo[b,d]furan), TCTA (4,4',4”-tris(carbazole-9-yl)-triphenylamine), and TPBi (1,3,5-tris(1-phenyl-1H-benzo[d]imidazole-2-yl)benzene). However, it is not limited to these, and may also include, for example, Alq3 (tris(8-hydroxyquinol) Lino(aluminum), ADN (9,10-di(naphthalene-2-yl)anthracene), TBADN (3-tert-butyl-9,10-di(naphtho-2-yl)anthracene), DSA (distylyl arylene), CDBP (4,4'-bis(9-carbazolyl)-2,2'-dimethyl-biphenyl), MADN (2-methyl-9,10-bis(naphthalene-2-yl)anthracene), CP1 (hexaphenylcyclotriphosphazene), UGH2 (1,4-bis(triphenylsilyl)benzene), DPSiO3 (hexaphenylcyclotrisiloxane), DPSiO4 (octaphenylcyclotetrasiloxane), etc. may be used as host materials.

[0162] The light-emitting layer EML contains a compound represented by the following chemical formula Ma or chemical formula Mb. The compound represented by the following chemical formula Ma or chemical formula Mb is used as a phosphorescent dopant material. In one embodiment, the compound represented by the chemical formula Ma or chemical formula Mb is also used as an auxiliary dopant material.

[0163] [ka] (Chemical formula Ma)

[0164] In the chemical formula Ma, Y1 to Y4 and Z1 to Z4 are each independently CR1 or N, and R1 to R4 are each 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 ring-forming aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted ring-forming heteroaryl group having 2 to 30 carbon atoms, or are bonded to adjacent groups to form a ring. In the chemical formula Ma, m is 0 or 1, and n is 2 or 3. In the chemical formula Ma, if m is 0, then n is 3, and if m is 1, then n is 2.

[0165] Compounds represented by the chemical formula Ma are used as phosphorescent dopants. The following group of compounds, M-a1 to M-a25, are used as phosphorescent dopants.

[0166] A compound represented by the chemical formula Ma can be any one of the compounds in the following group of compounds M-a1 to M-a21. However, the compounds M-a1 to M-a21 are illustrative examples, and the compound represented by the chemical formula Ma is not limited to those represented by the compounds M-a1 to M-a21.

[0167] [ka] [ka] [ka] [ka] [ka] [ka]

Chem.

[0168] Compound M-a1 and Compound M-a2 are used as red dopant materials, and Compound M-a3 to Compound M-a7 are used as green dopant materials.

[0169] [[ID=I4]]

Chem.

[0170] TIFF0007910907000065.tif148170

[0171] The compound represented by chemical formula M-b is used as a blue phosphorescent dopant or a green phosphorescent dopant. Further, in one embodiment, the compound represented by chemical formula M-b is further included in the emission layer EML as an auxiliary dopant.

[0172] The compound represented by chemical formula M-b is represented by any one of the following compounds. However, the following compounds are exemplary, and the compound represented by chemical formula M-b is not limited to those represented by the following compounds. [[ID=3I]]

[0173]

Chem.

Chem.

[0174] ]> In the above compound, R, R 38 , and R[[ID=I3]] 39Each is 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 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

[0175] The light-emitting layer EML further contains a compound represented by any one of the following chemical formulas F-a to F-c. The compounds represented by the following chemical formulas F-a to F-c are used as fluorescent dopant materials.

[0176] [Chemical formula] (Chemical formula F-a)

[0177] TIFF0007910907000069.tif87170

[0178] [Chemical formula] (Chemical formula F-b)

[0179] In chemical formula F-b, R a and R b are each independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 2,0 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 ring-forming carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or are bonded to each other adjacent groups to form a ring.

[0180] In chemical formula F-b, U and V are each independently a substituted or unsubstituted hydrocarbon ring having 5 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heterocyclic ring having 2 to 30 ring-forming carbon atoms.

[0181] In chemical formula Fb, the number of rings represented by U and V is either 0 or 1, independently of each other. For example, in chemical formula Fb, when the number of U or V is 1, one ring constitutes a fused ring in the part represented by U or V, and when the number of U or V is 0, it means that there are no rings represented by U or V. More specifically, 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 fused ring with a fluorene core in chemical formula Fb is a tetracyclic compound. Also, when the number of both U and V is 0, the fused ring with a fluorene core in chemical formula Fb is a tricyclic compound. Also, when the number of both U and V is 1, the fused ring with a fluorene core in chemical formula Fb is a quincyclic compound.

[0182] [ka] (Chemical formula Fc)

[0183] In the aforementioned chemical formula Fc, A1 and A2 are independently O, S, Se, or NR, respectively. m And R m R1~R 11 Each of these groups 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 boryl group, a substituted or unsubstituted oxy 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 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or may bond with adjacent groups to form a ring.

[0184] In the chemical formula Fc, A1 and A2 may each independently bond to a substituent on an adjacent ring to form a fused ring. For example, A1 and A2 may each independently form NR mIn this case, A1 may bond with R4 or R5 to form a ring. Also, A2 may bond with R7 or R8 to form a ring.

[0185] In one embodiment, the luminescent layer EML is a known dopant material, and includes styryl derivatives (e.g., 1,4-bis[2-(3-N-ethylcarbazol)vinyl]benzene (BCzVB), 4-(di-p-tolylamino)-4'-[(di-p-tolylamino)styryl]stilbene (DPAVB), N-(4-((E)-2-(6-((E)-4-(diphenylamino)styryl)naphthalen-2-yl)vinyl)phenyl This includes )-N-phenylbenzeneamine (N-BDAVBi), 4,4'-bis[2-(4-(N,N-diphenylamino)phenyl)vinyl]biphenyl (DPAVBi), perylene and its derivatives (e.g., 2,5,8,11-tetra-t-butylperylene (TBP)), pyrene and its derivatives (e.g., 1,1-dipylene, 1,4-dipyrenylbenzene, 1,4-bis(N,N-diphenylamino)pyrene), and the like.

[0186] In one embodiment, if a plurality of light-emitting layers (EMLs) are included, at least one of the light-emitting layers (EMLs) contains a known phosphorescent dopant material. For example, metal complexes containing iridium (Ir), platinum (Pt), osmium (Os), gold (Au), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), or thulium (Tm) may be used as phosphorescent dopants. Specifically, Flrpic (iridium(III)bis(4,6-difluorophenylpyridinate-N,C2')picolinate), Fir6 (bis(2,4-difluorophenylpyridinate)-tetrakis(1-pyrazolyl)borate-iridium(III)) or PtOEP (platinum-octaethylporphyrin) may be used as phosphorescent dopants. However, the embodiments are not limited thereto.

[0187] At least one luminescent layer (EML) contains a quantum dot material. The core of the quantum dot is selected from group II-VI compounds, group IIIIII-VI compounds, group I-III-VI compounds, group III-V compounds, group III-II-V compounds, group IV-VI compounds, group IV elements, group IV compounds, and combinations thereof.

[0188] Group II-VI compounds are binary compounds selected from the group consisting of CdSe, CdTe, CdS, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, and mixtures thereof, including CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHg A ternary compound selected from the group consisting of Te, HgZnS, HeZnSe, HeZnTe, MgZnSe, MgZnS, and mixtures thereof, and a quaternary compound selected from the group consisting of HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, and mixtures thereof.

[0189] Group III-VI compounds include binary compounds such as In2S3 and In2Se3, ternary compounds such as InGaS3 and InGaSe3, or any combination thereof.

[0190] Group I-III-VI compounds are selected from the group consisting of AgInS, AgInS2, CuInS, CuInS2, AgGaS2, CuGaS2, CuGaO2, AgGaO2, AgAlO2, and mixtures thereof, or from ternary compounds such as AgInGaS2 and CuInGaS2.

[0191] The III-V compounds are selected from the group consisting of 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, and 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. On the other hand, the III-V compounds further contain group II metals. For example, InZnP or the like may be selected as the III-II-V compound.

[0192] The IV-VI compounds are selected from the group consisting of 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, and quaternary compounds selected from the group consisting of SnPbSSe, SnPbSeTe, SnPbSTe, and mixtures thereof. The group IV elements are selected from the group consisting of Si, Ge, and mixtures thereof. The group IV compounds are binary compounds selected from the group consisting of SiC, SiGe, and mixtures thereof.

[0193] At this time, the binary compound, ternary compound, or quaternary compound exists in the particles at a uniform concentration or is divided into a state where the concentration distribution is partially different and exists in the same particle. Also, one quantum dot may have a core / shell structure surrounding another quantum dot. In the core / shell structure, there is a concentration gradient such that the concentration of the elements present in the shell decreases towards the core.

[0194] In some embodiments, quantum dots have a core / shell structure comprising a core containing the aforementioned nanocrystals and a shell surrounding the core. The shell of the quantum dot acts as a protective layer to prevent chemical degradation of the core and maintain its semiconductor properties, and / or as a charging layer to impart electrophoretic properties to the quantum dot. The shell can be a single layer or multiple layers. Examples of quantum dot shells include metallic or nonmetallic oxides, semiconductor compounds, or combinations thereof.

[0195] For example, metallic or nonmetallic oxides include binary compounds such as SiO2, Al2O3, TiO2, ZnO, MnO, Mn2O3, Mn3O4, CuO, FeO, Fe2O3, Fe3O4, CoO, Co3O4, and NiO, or ternary compounds such as MgAl2O4, CoFe2O4, NiFe2O4, and CoMn2O4, but the present invention is not limited to these.

[0196] Furthermore, semiconductor compounds include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AlSb, and others, but the present invention is not limited to these.

[0197] Quantum dots have an emission wavelength spectrum with a full width at half maximum (FWHM) of approximately 45 nm or less, preferably approximately 40 nm or less, and more preferably approximately 30 nm or less. Within this range, color purity and color reproducibility can be improved. Furthermore, since the light emitted through such quantum dots is emitted in all directions, the optical viewing angle is improved.

[0198] Furthermore, the form of the quantum dots is not limited to those commonly used in this field, but more specifically, spherical, pyramidal, multi-arm, or cubic nanoparticles, nanotubes, nanowires, nanofibers, or nanoplate-like particles may be used.

[0199] Quantum dots can adjust the hue of the light they emit by changing the size of the particle, resulting in quantum dots having a variety of emission hues, such as blue, red, and green.

[0200] In one embodiment of the light-emitting element ED shown in Figures 3 to 6, the electron transport region ETR is provided on the light-emitting layer EML. The electron transport region ETR includes, but is not limited to, at least one of the hole blocking layer HBL, the electron transport layer ETL, and the electron injection layer EIL.

[0201] The electron transport region (ETR) has a multilayer structure consisting of a single layer made of a single material, a single layer made of multiple different materials, or multiple layers made of multiple different materials.

[0202] For example, the electron transport region (ETR) may have a single-layer structure of an electron injection layer (EIL) or electron transport layer (ETL), or a single-layer structure consisting of an electron injection material and an electron transport material. Furthermore, the electron transport region (ETR) may have a single-layer structure consisting of multiple different materials, or it may have structures such as an electron transport layer (ETL) / electron injection layer (EIL), hole blocking layer (HBL) / electron transport layer (ETL) / electron injection layer (EIL), or electron transport layer (ETL) / buffer layer (not shown) / electron injection layer (EIL), stacked sequentially from the light-emitting layer (EML). The thickness of the electron transport region (ETR) may be, for example, approximately 100 nm to approximately 150 nm.

[0203] The electron transport region (ETR) is formed using a variety of methods, including vacuum deposition, spin coating, casting, LB (Laser-Based) deposition, inkjet printing, laser printing, and laser thermal transfer (LITI).

[0204] The electron transport region (ETR) includes compounds represented by the following chemical formula ET-1.

[0205] [ka] (Chemical formula ET-1)

[0206] In the chemical formula ET-1, at least one of X1 to X3 is N, and the others are CR. a R a Each of the following is 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 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, and each of Ar1 to Ar3 is 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 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

[0207] In chemical formula ET-1, a to c are each independently integers between 0 and 10. In chemical formula ET-1, L1 and L3 are each independently arylene groups with 6 to 30 ring-forming carbon atoms, either directly bonded, substituted, or unsubstituted, or heteroarylene groups with 2 to 30 ring-forming carbon atoms, either substituted or unsubstituted. On the other hand, if a to c are integers greater than or equal to 2, then multiple L1 and L3 groups are each independently substituted or unsubstituted arylene groups with 6 to 30 ring-forming carbon atoms, or heteroarylene groups with 2 to 30 ring-forming carbon atoms, either substituted or unsubstituted.

[0208] The electron transport region (ETR) includes anthracene compounds. However, the electron transport region ETR is not limited to these; for example, Alq3 (tris(8-hydroxyquinolinato)aluminum), 1,3,5-tri[(3-pyridyl)phen-3-yl]benzene, 2,4,6-tris(3'-pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine, 2-(4-(N-phenylbenzimidazole-1-yl)phenyl)-9,10-dinaphthylanthracene, TPBi (1,3,5-tri(1-phenyl-1H-benzo[d]imidazole-2-yl)benzene), BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline), Bphen (4,7-diphenyl-1,10-phenanthroline), TAZ (3-(4-biphenylyl)-4-phenyl-5-tert-butyl It may also contain phenyl-1,2,4-triazole, NTAZ (4-(naphthalene-1-yl)-3,5-diphenyl-4H-1,2,4-triazole), tBu-PBD (2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole), BAlq (bis(2-methyl-8-quinolinolato-N1,O8)-(1,1'-biphenyl-4-orato)aluminum), Bebq2 (beryllium bis(benzoquinoline-10-orato), ADN (9,10-di(naphthalene-2-yl)anthracene), BmPyPhB (1,3-bis[3,5-di(pyridine-3-yl)phenyl]benzene), TSPO1 (diphenyl(4-(triphenylsilyl)phenyl)phosphine oxide), and mixtures thereof.

[0209] Furthermore, the electron transport region (ETR) includes 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 electron transport region (ETR) may include KI:Yb, RbI:Yb, etc., as co-deposited materials. On the other hand, the electron transport region (ETR) may also use metal oxides such as Li2O and BaO, or Liq(8-hydroxylithium quinolate), but the embodiments are not limited to these. The electron transport region (ETR) also consists of a material obtained by mixing an electron transport material with an insulating organometallic salt. The organometallic salt is a material with an energy band gap of about 4 eV or more. For more details, organometallic salts include, for example, metal acetate, metal benzoate, metal acetoacetate, metal acetylacetonate, or metal stearate.

[0210] The electron transport region (ETR) may, but is not limited to, further contain at least one of BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) and Bphen (4,7-diphenyl-1,10-phenanthroline) in addition to the materials described above.

[0211] The electron transport region ETR comprises the aforementioned electron transport region compound, at least one of the electron injection layer EIL, electron transport layer ETL, and hole blocking layer HBL.

[0212] If the electron transport region (ETR) includes an electron transport layer (ETL), the thickness of the electron transport layer (ETL) may be approximately 10 nm to 100 nm, for example, approximately 15 nm to 50 nm. When the thickness of the electron transport layer (HTL) satisfies the above-mentioned range, sufficient electron transport characteristics can be obtained without a substantial increase in driving voltage. If the electron transport region (ETR) includes an electron injection layer (EIL), the thickness of the electron injection layer (EIL) may be approximately 1 Å to 10 nm, or approximately 3 Å to 9 nm. When the thickness of the electron injection layer (EIL) satisfies the above-mentioned range, sufficient electron injection characteristics can be obtained without a substantial increase in driving voltage.

[0213] The second electrode EL2 is provided on the electron transport region ETR. The second electrode EL2 is a common electrode. The second electrode EL2 may be a cathode or an anor rond, but the embodiment is not limited thereto. For example, when the first electrode EL1 is an anode, the second electrode may be a cathode, and when the first electrode EL1 is a cathode, the second electrode may be an anode. The second electrode EL2 includes at least one selected from Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, In, Sn, and Zn, two or more compounds selected from these, a mixture of two or more selected from these, or oxides thereof.

[0214] The second electrode EL2 is a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. When the second electrode EL2 is a transmissive electrode, it is made of a transparent metal oxide, such as ITO, IZO, ZnO, ITZO, etc.

[0215] When the second electrode EL2 is a semi-transparent or reflective electrode, the second electrode EL2 may contain Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca (a layered structure of LiF and Ca), LiF / Al (a layered structure of LiF and Al), Mo, Ti, Yb, W, or compounds or mixtures containing these (e.g., AgMg, AgYb, or MgYb). Alternatively, the second electrode EL2 is a multi-layer structure including a reflective or semi-transparent film made of a material, and a transparent conductive film made of ITO, IZO, ZnO, ITZO, etc. For example, the second electrode EL2 may contain 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.

[0216] Although not shown in the diagram, the second electrode EL2 is connected to an auxiliary electrode. When the second electrode EL2 is connected to the auxiliary electrode, the resistance of the second electrode EL2 is reduced.

[0217] On the other hand, a capping layer CPL is further disposed on the second electrode EL2 of the light-emitting element ED in one embodiment. The capping layer CPL may be multilayer or monolayer.

[0218] In one embodiment, the capping layer (CPL) is an organic or inorganic layer. For example, if the capping layer (CPL) contains an inorganic substance, the inorganic substance may include alkali metal compounds such as LiF, alkaline earth compounds such as MgF2, SiON, SiNx, SiOy, and the like.

[0219] For example, if the capping layer CPL contains organic matter, the organic matter may include α-NPD, NPB, TPD, m-MTDATA, Alq3, CuPc, TPD15 (N4,N4,N4',N4'-tetra(biphenyl-4-yl)biphenyl-4,4'-diamine), TCTA (4,4',4"-tris(carbazolesol-9-yl)triphenylamine), or epoxy resin, or acrylates such as methacrylate. However, the embodiments are not limited to these, and the capping layer CPL may contain at least one of the compounds P1 to P5 described below.

[0220] [ka] [ka] [ka] [ka] [ka]

[0221] On the other hand, the refractive index of the capping layer CPL is 1.6 or higher. More specifically, for light in the wavelength range of 550 nm to 660 nm, the refractive index of the capping layer CPL is 1.6 or higher.

[0222] Figures 7 and 8 are cross-sectional views corresponding to a display device according to one embodiment, respectively. The following description will be given with reference to Figures 7 and 8. In the description of the display device corresponding to one embodiment, any content that overlaps with the content described in Figures 1 to 6 above will not be explained again, and the focus will be on the differences.

[0223] Referring to Figure 7, one embodiment of the display device DD includes a display panel DP including a display element layer DP-ED, an optical control layer CCL disposed on the display panel DP, and a color filter layer CFL.

[0224] In one embodiment shown in Figure 7, the display panel DP includes a base layer BS, a circuit layer DP-CL provided on the base layer BS, and a display element layer DP-ED, the display element layer DP-ED including a light-emitting element ED.

[0225] The light-emitting element ED includes a first electrode EL1, a hole transport region HTR placed on the first electrode EL1, an emissive layer EML placed on the hole transport region HTR, an electron transport region ETR placed on the emissive layer EML, and a second electrode EL2 placed on the electron transport region ETR. On the other hand, the structure of the light-emitting element ED shown in Figure 7 is the same as the structure of the light-emitting elements shown in Figures 3 to 6 described above.

[0226] Referring to Figure 7, the light-emitting layer EML is positioned within the aperture OH defined in the pixel definition film PDL. For example, the light-emitting layers EML provided to correspond to each light-emitting region PXA-R, PXA-G, and PXA-B, separated by the pixel definition film PDL, emit light in the same wavelength range. In one embodiment of the display device DD, the light-emitting layer EML emits blue light. On the other hand, contrary to the illustration, the light-emitting layer EML in one embodiment may be provided as a common layer for the entire light-emitting regions PXA-R, PXA-G, and PXA-B.

[0227] At least one of the luminescent layers ETL provided corresponding to luminescent regions PXA-R, PXA-G, and PXA-B contains the polycyclic compound of one embodiment represented by chemical formula 1 described above. At least one of the luminescent layers EML provided corresponding to luminescent regions PXA-R, PXA-G, and PXA-B contains the polycyclic compound of one embodiment represented by chemical formula 1 described above, and the remaining luminescent layers EML contain known additional fluorescent materials, phosphorescent materials, or quantum dots, etc. However, the embodiments are not limited thereto.

[0228] The optical control layer (CCL) is positioned above the display panel (DP). The CCL contains photoconverters, such as quantum dots or phosphors. These photoconverters convert the wavelength of the light they receive and emit it. In other words, the CCL is either a layer containing quantum dots or a layer containing phosphors.

[0229] The optical control layer (CCL) includes multiple optical control units CCP1, CCP2, and CCP3. The optical control units CCP1, CCP2, and CCP3 are spaced apart from each other.

[0230] Referring to Figure 7, a segmented pattern BMP is provided between the optical control units CCP1, CCP2, and CCP3, which are spaced apart from each other, but the embodiment is not limited to this. In Figure 7, it is shown that the segmented pattern BMP does not 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 the segmented pattern BMP in at least part.

[0231] The optical control layer CCL includes a first optical control unit CCP1 which includes a first quantum dot QD1 that converts the first color light provided from the light-emitting element ED into second color light, a second optical control unit CCP2 which includes a second quantum dot QD2 that converts the first color light into third color light, and a third optical control unit CCP3 which transmits the first color light.

[0232] In one embodiment, the first optical control unit CCP1 provides red light, which is the second color light, and the second optical control unit CCP2 provides green light, which is the third color light. The third optical control unit CCP3 transmits and provides blue light, which is the first color light, provided from the light-emitting element ED. For example, the first quantum dot QD1 may be a red quantum dot, and the second quantum dot QD2 may be a green quantum dot. The same provisions as described above apply to quantum dots QD1 and QD2.

[0233] Furthermore, the optical control layer CCL further includes a scatterer SP. The first optical control unit CCP1 includes a first quantum dot QD1 and a scatterer SP, the second optical control unit CCP2 includes a second quantum dot QD2 and a scatterer SP, and the third optical control unit CCP3 includes a scatterer SP but does not include a quantum dot.

[0234] The scatterer SP is an inorganic particle. For example, the scatterer SP may contain at least one of TiO2, ZnO, Al2O3, SiO2, and hollow silica. The scatterer SP contains at least one of TiO2, ZnO, Al2O3, SiO2, and hollow silica, or it is a mixture of two or more substances selected from TiO2, ZnO, Al2O3, SiO2, and hollow silica.

[0235] The first optical control unit CCP1, the second optical control unit CCP2, and the third optical control unit CCP3 each include base resins BR1, BR2, and BR3 for dispersing quantum dots QD1 and QD2 and scatterers SP. In one embodiment, the first optical control unit CCP1 includes first quantum dots QD1 and scatterers SP dispersed in the first base resin BR1, the second optical control unit CCP2 includes second quantum dots QD2 and scatterers SP dispersed in the second base resin BR2, and the third optical control unit CCP1 includes scatterers SP dispersed in the third base resin BR3. The base resins BR1, BR2, and BR3 are media in which the quantum dots QD1 and QD2 and scatterers SP are dispersed, and consist of various resin compositions generally referred to as binders. For example, the base resins BR1, BR2, and BR3 may be acrylic resins, urethane resins, silicone resins, epoxy resins, etc. The base resins BR1, BR2, and BR3 are transparent resins. In one embodiment, the first base resin BR1, the second base resin BR2, and the third base resin BR3 are either the same as or different from each other.

[0236] The light control layer CCL includes a barrier layer BFL1. The barrier layer BFL1 prevents the penetration of moisture and / or oxygen (hereinafter referred to as "moisture / oxygen"). The barrier layer BFL1 is positioned on top of the light control units CCP1, CCP2, and CCP3 to block them from being exposed to moisture / oxygen. On the other hand, the barrier layer BFL1 covers the light control units CCP1, CCP2, and CCP3. A barrier layer BLF2 may also be provided between the light control units CCP1, CCP2, and CCP3 and the color filter layer CFL.

[0237] The barrier layers BFL1 and BFL2 include at least one inorganic layer. In other words, the barrier layers BFL1 and BFL2 are formed by including inorganic materials. For example, the barrier layers BFL1 and BFL2 are formed by including silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, hafnium nitride, tantalum nitride, silicon oxide, aluminum oxide, titanium oxide, tin oxide, cerium oxide, and silicon oxynitride, or a metal thin film with sufficient light transmittance. On the other hand, the barrier layers BFL1 and BFL2 further include an organic film. The barrier layers BFL1 and BFL2 consist of a single layer or multiple layers.

[0238] In one embodiment of the display device DD, the color filter layer CFL is placed on top of the light control layer CCL. For example, the color filter layer CFL may be placed directly on top of the light control layer CCL. In this case, the barrier layer BFL2 is omitted.

[0239] The color filter layer CFL includes a light-shielding section BM and filters CF-B, CF-G, and CF-R. The color filter layer CFL includes a first filter CF1 that transmits second-color light, a second filter CF2 that transmits third-color light, and a third filter CF3 that transmits first-color light. For example, the first filter CF1 may be a red filter, the second filter CF2 a green filter, and the third filter CF3 a blue filter. Each of the first, second, and third filters CF1, CF2, and CF3 contains a polymer photosensitive resin and a pigment or dye. The first filter CF1 contains a red pigment or dye, the second filter CF2 contains a green pigment or dye, and the third filter CF3 contains a blue pigment or dye. On the other hand, the embodiments are not limited to this, and the third filter CF3 does not have to contain a pigment or dye. The third filter CF3 contains a polymer photosensitive resin and does not contain a pigment or dye. The third filter CF3 is transparent. The third filter CF3 is made of a transparent photosensitive resin.

[0240] In one embodiment, the first filter CF1 and the second filter CF2 are yellow filters. The first filter CF1 and the second filter CF2 may be provided as a single unit without being separated from each other.

[0241] The light-shielding section BM is a black matrix. The light-shielding section BM is formed by comprising an organic or inorganic light-shielding material containing a black pigment or black dye. The light-shielding section BM prevents light leakage and demarcates the boundaries between adjacent filters CF1, CF2, and CF3. In one embodiment, the light-shielding section BM is formed by a blue filter.

[0242] The first to third filters CF1, CF2, and CF3 are positioned to correspond to the red emission region PXA-R, the green emission region PXA-G, and the blue emission region PXA-B, respectively. A base substrate BL is placed on top of the color filter layer CFL. The base substrate BL is a component that provides a base surface on which the color filter layer CFL and the light control layer CCL are placed. The base substrate BL can be a glass substrate, a metal substrate, a plastic substrate, etc. However, the embodiment is not limited to these, and the base substrate BL may be an inorganic layer, an organic layer, or a composite material layer. Also, the base substrate BL may be omitted in one embodiment, contrary to what is shown in the figures.

[0243] Figure 8 is a cross-sectional view showing a part of a display device according to one embodiment. Figure 8 shows a cross-sectional view of a part corresponding to the display panel DP in Figure 7. In the display device DD-TD of one embodiment, the light-emitting element ED-BT includes a plurality of light-emitting structures OL-B1, OL-B2, and OL-B3. The light-emitting element ED-BT includes a first electrode EL1 and a second electrode EL2 facing each other, and a plurality of light-emitting structures OL-B1, OL-B2, and OL-B3 that are sequentially stacked in the thickness direction between the first electrode EL1 and the second electrode EL2. Each of the light-emitting structures OL-B1, OL-B2, and OL-B3 includes a light-emitting layer EML (Figure 7), and a hole transport region HTR and an electron transport region ETR arranged with the light-emitting layer EML (Figure 7) in between.

[0244] In other words, the light-emitting element ED-BT included in the display device DD-TD of one embodiment is a light-emitting element with a tandem structure that includes multiple light-emitting layers.

[0245] In one embodiment shown in Figure 8, the light emitted from each of the light-emitting structures OL-B1, OL-B2, and OL-B3 is 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 may be different from each other. For example, an ED-BT light-emitting element that includes multiple light-emitting structures OL-B1, OL-B2, and OL-B3 that emit light in different wavelength ranges may emit white light.

[0246] A charge generation layer CGL is positioned between adjacent light-emitting structures OL-B1, OL-B2, and OL-B3. The charge generation layer CGL includes a p-type charge generation layer and / or an n-type charge generation layer. At least one of the light-emitting structures OL-B1, OL-B2, and OL-B3 included in the display device DD-TD of one embodiment contains the polycyclic compound of the above-described embodiment.

[0247] A light-emitting element ED according to one embodiment of the present invention exhibits improved luminous efficiency and improved long-life characteristics by including the polycyclic compound of the above embodiment in at least one light-emitting layer EML disposed between the first electrode EL1 and the second electrode EL2.

[0248] The polycyclic compound of the above-described embodiment contains a bulky cyclic compound such as triptycene or carborane as a linker. Having a structure in which the polycyclic rings of two DABNA derivatives are bonded by such a linker suppresses aggregation between the polycyclic compounds, resulting in excellent film properties when used as a light-emitting material. Furthermore, the polycyclic compound of the embodiment exhibits thermally activated delayed fluorescence emission. When the polycyclic compound of the embodiment is used as a light-emitting layer material, the light-emitting device of the embodiment exhibits excellent luminescence efficiency and long lifetime characteristics.

[0249] Furthermore, the light-emitting element of one embodiment exhibits improved luminous efficiency and long lifetime characteristics by reducing energy loss in the triplet state and increasing the proportion of fluorescence emission, by including a hole-transporting host, an electron-transporting host, an organometallic complex auxiliary dopant that is a phosphorescent sensor, and a luminescent dopant that is a polycyclic compound of one embodiment of the present invention in the light-emitting layer. [Examples]

[0250] The following describes in detail a polycyclic compound and a light-emitting element of one embodiment according to one embodiment of the present invention, with reference to examples and comparative examples. Furthermore, the following examples are illustrative to aid in understanding the present invention, and the scope of the present invention is not limited thereto.

[0251] 1. Synthesis of polycyclic compounds First, the synthesis method of compounds according to this embodiment will be explained in detail, with examples of the synthesis methods for compounds 1 to 6. Furthermore, the synthesis method of polycyclic compounds described below is just one example, and the synthesis method of polycyclic compounds according to the embodiments of the present invention is not limited to the following examples.

[0252] <Synthesis of Compound 1> Polycyclic compound 1 according to one example can be synthesized, for example, by the steps of the following reaction formula 1.

[0253] [Reaction Equation 1] [ka]

[0254] Intermediate compound 1-1 (10.8 g, 40.0 mmol) and Intermediate compound 1-2 (22.5 g, 80.0 mmol) were placed in a flask, and toluene was added. Next, sodium tert-butoxide, Pd2(dba)3 (tris(dibenzylideneacetone)dipalladium(0)), and tri-tert-butylphosphonium tetrafluoroborate were added, and the mixture was stirred at 110°C and refluxed for 6 hours. The resulting residue was purified by silica gel chromatography and then recrystallized in a mixed solvent of chloroform and hexane to obtain 21.0 g of Intermediate compound 1-3 (78% yield).

[0255] Next, intermediate compound 1-3 (6.71 g, 10.0 mmol) and boron triiodide (3.92 g, 10.0 mmol) were placed in a flask, and 1,2-dichlorobenzene was added. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 2.31 g of intermediate compound 1-4 (34% yield).

[0256] Next, intermediate compound 1-4 (2.31 g, 3.4 mmol) and intermediate compound 1-5 (0.58 g, 1.07 mmol) were placed in a flask, and a mixed solvent of toluene and EtOH (ethanol) was added. Then, a 0.3 M aqueous solution of Na2CO3 (aqueous sodium carbonate solution) that had been bubbling with nitrogen for more than 10 minutes, and Pd(PPh3)4 (tetrakis(triphenylphosphine)palladium(0)) were added, and the mixture was stirred at 100°C and refluxed overnight. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 2.10 g of compound 1 of the present invention (yield 80%). [MS: m / z[M]+calcd1539.94;found,1539.80]

[0257] <Synthesis of Compound 2> Polycyclic compound 2 according to one example can be synthesized, for example, by the steps of reaction formula 2 below.

[0258] [Reaction Equation 2] [ka]

[0259] Intermediate compound 2-1 (10.8 g, 40.0 mmol) and intermediate compound 2-2 (25.7 g, 80.0 mmol) were placed in a flask, and toluene was added. Next, sodium tert-butoxide, Pd2(dba)3, and tri-tert-butylphosphonium tetrafluoroborate were added, and the mixture was stirred at 110°C and refluxed for 6 hours. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 22.3 g of intermediate compound 2-3 (74% yield).

[0260] Next, intermediate compound 2-3 (7.51 g, 10.0 mmol) and boron triiodide (3.92 g, 10.0 mmol) were placed in a flask, and 1,2-dichlorobenzene was added. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 2.05 g of intermediate compound 2-4 (27% yield).

[0261] Next, intermediate compound 2-4 (3.04 g, 4.00 mmol) and intermediate compound 2-5 (0.68 g, 2.00 mmol) were placed in a flask, and a mixed solvent of toluene and EtOH was added. Then, a 0.3 M aqueous solution of Na2CO3, which had been bubbling with nitrogen for more than 10 minutes, and Pd(PPh3)4 were added, and the mixture was stirred at 100°C and refluxed overnight. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 2.31 g of compound 2 of the present invention (yield 68%). [MS: m / z[M]+calcd1699.69;found,1698.79]

[0262] <Synthesis of Compound 3> Polycyclic compound 3 according to one example can be synthesized, for example, by the steps of reaction formula 3 below.

[0263] [Reaction Equation 3] [ka]

[0264] Intermediate compound 3-1 (10.8 g, 40.0 mmol) and intermediate compound 3-2 (13.5 g, 80.0 mmol) were placed in a flask, and toluene was added. Next, sodium tert-butoxide, Pd2(dba)3, and tri-tert-butylphosphonium tetrafluoroborate were added, and the mixture was stirred at 110°C and refluxed for 6 hours. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 13.8 g of intermediate compound 3-3 (77% yield).

[0265] Next, intermediate compound 3-3 (6.70 g, 15.0 mmol) and boron triiodide (5.87 g, 15.0 mmol) were placed in a flask, and 1,2-dichlorobenzene was added. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 2.59 g of intermediate compound 3-4 (38% yield).

[0266] Next, intermediate compounds 3-4 (1.64 g, 3.60 mmol) and intermediate compound 3-5 (0.62 g, 1.80 mmol) were placed in a flask, and a mixed solvent of toluene and EtOH was added. Then, a 0.3 M aqueous solution of Na2CO3, which had been bubbling with nitrogen for more than 10 minutes, and Pd(PPh3)4 were added, and the mixture was stirred at 100°C and refluxed overnight. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 1.43 g of compound 3 of the present invention (yield 73%). [MS: m / z[M]+calcd1090.44;found,1090.40]

[0267] <Synthesis of Compound 4> Polycyclic compound 4 according to one example can be synthesized, for example, by the steps of reaction formula 4 below.

[0268] [Reaction Equation 4] [ka]

[0269] Intermediate compound 4-1 (15.7 g, 50.0 mmol) and intermediate compound 4-2 (28.1 g, 100.0 mmol) were placed in a flask, and toluene was added. Next, sodium tert-butoxide, Pd2(dba)3, and tri-tert-butylphosphonium tetrafluoroborate were added, and the mixture was stirred at 80°C for 6 hours. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 14.3 g of intermediate compound 4-3 (40% yield).

[0270] Next, intermediate compound 4-3 (14.0 g, 19.6 mmol) and boron triiodide (7.67 g, 19.6 mmol) were placed in a flask, and 1,2-dichlorobenzene was added. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 1.42 g of intermediate compound 4-4 (10% yield).

[0271] Next, intermediate compound 4-4 (7.24 g, 10.0 mmol) was placed in a flask and THF (tetrahydrofuran) was added. Then, CuI, Pd(PPh3)4, trimethylsilylacetylene (TMSA; 1.96 g, 20.0 mmol), and Et3N (triethylamine) were added and the mixture was stirred at 60°C for 24 hours. The resulting residue was purified by silica gel chromatography and then recrystallized in a mixed solvent of chloroform and hexane to obtain 4.38 g of intermediate compound 4-5 (58% yield).

[0272] Next, intermediate compound 4-5 (22.7 g, 30.0 mmol) was placed in a flask, and THF, methanol (MeOH), and KOH (1M) aqueous solution were added. The mixture was stirred at room temperature for 1 hour. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 2.41 g of intermediate compound 4-6 (12% yield).

[0273] Next, intermediate compound 4-6 (2.27 g, 3.40 mmol) was placed in a flask and THF was added. Intermediate compound 4-4 (2.46 g, 3.40 mmol) was added, methanol and KOH (1M) aqueous solution were added, and the mixture was stirred at 60°C for 24 hours. The resulting residue was purified by silica gel chromatography to obtain 0.27 g of intermediate compound 4-7 (6% yield).

[0274] Next, decaborane (0.026 g, 0.21 mmol) and N,N-dimethylaniline were added to toluene, and the mixture was stirred at room temperature for 30 minutes and then at 100°C for 2 hours. Then, the temperature was lowered to room temperature, and intermediate compounds 4-7 (0.27 g, 0.21 mmol) were added and refluxed for 16 hours. The resulting residue was purified by silica gel chromatography to obtain 0.10 g of compound 4 (yield 48%).

[0275] <Synthesis of Compound 5> Polycyclic compound 5 according to one example can be synthesized, for example, by the steps of the following reaction formula 5.

[0276] [Reaction Equation 5] [ka]

[0277] Intermediate compound 5-1 (15.7 g, 50.0 mmol) and intermediate compound 5-2 (32.1 g, 100.0 mmol) were placed in a flask, and toluene was added. Next, sodium tert-butoxide, Pd2(dba)3, and tri-tert-butylphosphonium tetrafluoroborate were added, and the mixture was stirred at 80°C for 6 hours. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 13.9 g of intermediate compound 5-3 (35% yield).

[0278] Next, intermediate compound 5-3 (13.9 g, 17.5 mmol) and boron triiodide (6.85 g, 17.5 mmol) were placed in a flask, and 1,2-dichlorobenzene was added. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 0.99 g of intermediate compound 5-4 (7% yield).

[0279] Next, intermediate compound 5-4 (8.04 g, 10.0 mmol) was placed in a flask and THF was added. Then, CuI, Pd(PPh3)4, trimethylsilylacetylene (TMSAl; 1.96 g, 20.0 mmol), and Et3N were added and the mixture was stirred at 60°C for 24 hours. The resulting residue was purified by silica gel chromatography and then recrystallized in a mixed solvent of chloroform and hexane to obtain 5.18 g of intermediate compound 5-5 (62% yield).

[0280] Next, intermediate compound 5-5 (25.1 g, 30.0 mmol) was placed in a flask, and THF, methanol, and KOH (1M) aqueous solution were added, and the mixture was stirred at room temperature for 1 hour. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 2.03 g of intermediate compound 5-6 (9% yield).

[0281] Next, intermediate compound 5-6 (1.87 g, 2.50 mmol) was placed in a flask and THF was added. Intermediate compound 5-4 (2.01 g, 2.50 mmol) was added, methanol and KOH (1 M) aqueous solution were added, and the mixture was stirred at 60°C for 24 hours. The resulting residue was purified by silica gel chromatography to obtain 0.29 g of intermediate compound 5-7 (8% yield).

[0282] Next, decaborane (0.03 g, 0.25 mmol) and N,N-dimethylaniline were added to toluene, and the mixture was stirred at room temperature for 30 minutes and then at 100°C for 2 hours. Then, the temperature was lowered to room temperature, and intermediate compounds 5-7 (0.20 g, 0.25 mmol) were added and refluxed for 16 hours. The resulting residue was purified by silica gel chromatography to obtain 0.18 g of compound 5 (yield 45%).

[0283] <Synthesis of Compound 6> The polycyclic compound 6 according to one example can be synthesized, for example, by the steps of the following reaction formula 6.

[0284] [Reaction Equation 6] [ka]

[0285] Intermediate compound 6-1 (15.7 g, 50.0 mmol) and intermediate compound 6-2 (16.9 g, 100.0 mmol) were placed in a flask, and toluene was added. Next, sodium tert-butoxide, Pd2(dba)3, and tri-tert-butylphosphonium tetrafluoroborate were added, and the mixture was stirred at 80°C for 6 hours. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 7.87 g of intermediate compound 6-3 (32% yield).

[0286] Next, intermediate compound 6-3 (7.86 g, 16.0 mmol) and boron triiodide (6.26 g, 16.0 mmol) were placed in a flask, and 1,2-dichlorobenzene was added. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 0.4 g of intermediate compound 6-4 (5% yield).

[0287] Next, intermediate compound 6-4 (3.00 g, 6.00 mmol) was placed in a flask and THF was added. Then, CuI, Pd(PPh3)4, trimethylsilylacetylene (TMSAl; 1.18 g, 12.0 mmol), and Et3N were added and the mixture was stirred at 60°C for 24 hours. The resulting residue was purified by silica gel chromatography and then recrystallized in a mixed solvent of chloroform and hexane to obtain 2.07 g of intermediate compound 6-5 (65% yield).

[0288] Next, intermediate compound 6-5 (15.9 g, 30.0 mmol) was placed in a flask, and THF, methanol, and KOH (1M) aqueous solution were added, and the mixture was stirred at room temperature for 1 hour. The resulting residue was purified by silica gel chromatography, and then recrystallized in a mixed solvent of chloroform and hexane to obtain 1.60 g of intermediate compound 6-6 (12% yield).

[0289] Next, intermediate compound 6-6 (1.60 g, 3.60 mmol) was placed in a flask and THF was added. Intermediate compound 6-4 (1.80 g, 3.60 mmol) was added, methanol and KOH (1 M) aqueous solution were added, and the mixture was stirred at 60°C for 24 hours. The resulting residue was purified by silica gel chromatography to obtain 0.22 g of intermediate compound 6-7 (7% yield).

[0290] Next, decaborane (0.034 g, 0.28 mmol) and N,N-dimethylaniline were added to toluene, and the mixture was stirred at room temperature for 30 minutes and then at 100°C for 2 hours. The temperature was then lowered to room temperature, and intermediate compounds 6-7 (0.22 g, 0.25 mmol) were added and refluxed for 16 hours. The resulting residue was purified by silica gel chromatography to obtain 0.11 g of compound 6 (yield 42%).

[0291] 2. Fabrication and evaluation of light-emitting devices (Fabrication of light-emitting elements) A light-emitting device of one example, containing the polycyclic compound of one example in the light-emitting layer, was manufactured by the following method. The polycyclic compounds of Compounds 1 to 4 described above were used as light-emitting dopants in the light-emitting layer to fabricate the light-emitting devices of Examples 1 to 4.

[0292] Comparative Examples 1 and 2 were fabricated using the comparative compounds C1 and C2 described below as light-emitting dopant materials for the light-emitting layer, respectively.

[0293] The comparative compounds used in the fabrication of the light-emitting element are shown below.

[0294] (Comparative Compounds) [ka] [ka]

[0295] Other compounds used in the fabrication of light-emitting elements are listed below.

[0296] (Other compounds used in the fabrication of the device) [ka] [ka] [ka] [ka]

[0297] A glass substrate patterned with ITO was cleaned, and a hole injection layer was formed by depositing NPD to a thickness of 30 nm. Next, a hole transport layer was formed by depositing TCTA to a thickness of 20 nm. A luminescence auxiliary layer with a thickness of 10 nm was formed by vacuum depositing CzSi on top of the hole transport layer.

[0298] Next, a 25 nm thick luminescent layer was formed by simultaneously depositing a first host, second host, auxiliary dopant, and luminescent dopant in a weight ratio of 70:30:15:0.5. 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 luminescent layer. The comparative and example compounds were used as the luminescent dopant.

[0299] Next, TSPO1 was deposited to a thickness of 20 nm to form an electron transport layer, TPBi was deposited to a thickness of 30 nm to form a buffer layer, and then LiF was deposited to a thickness of 1 nm to form an electron injection layer.

[0300] Next, a second electrode was formed by providing an Al layer with a thickness of 300 nm.

[0301] (Evaluation of light-emitting element characteristics) Table 1 shows the evaluation results of the light-emitting elements for Examples 1 to 4, Comparative Example 1, and Comparative Example 2. Table 1 compares the luminous efficiency, emission wavelength, and device lifetime of the fabricated light-emitting elements. The characteristic evaluation results for the examples and comparative examples shown in Table 1 show 10 mA / cm². 2 This shows the luminous efficiency value at the given current density. The device lifetime is 10 mA / cm². 2 This indicates the time it takes for the brightness to decrease from the initial brightness to 95% (a 5% decrease in brightness) when continuously driven at the specified current density.

[0302] The current density, driving voltage, and luminous efficiency of the light-emitting elements in the examples and comparative examples were measured in a darkroom using a Keithley Instruments 2400 series source meter, a Konica Minolta CS-200 colorimeter, and the National Instruments Japan LabVIEW 2.0 measurement PC program.

[0303] [Table 1]

[0304] Referring to the results in Table 1, it can be seen that the light-emitting devices of the examples and comparative examples emit blue light having an emission wavelength of 461-462 nm. Furthermore, referring to the results in Table 1, it can be seen that in the example of a light-emitting device in which the polycyclic compound of one embodiment of the present invention is used as the light-emitting dopant material of the light-emitting layer, it exhibits superior brightness efficiency and improved device lifetime characteristics compared to the comparative example.

[0305] In other words, referring to Table 1, it can be seen that Examples 1 to 4, compared to the light-emitting dopants used in the light-emitting layers of Comparative Examples 1 to 2, contain polycyclic compounds with a dimeric structure bonded by a bulky linker, resulting in longer lifetime and higher efficiency characteristics.

[0306] The polycyclic compound according to one embodiment has a dimeric compound structure bonded by a large-volume linker and is used as a delayed fluorescence emission material, contributing to the high efficiency and long lifespan characteristics of light-emitting devices. Furthermore, the light-emitting device according to one embodiment exhibits both long lifespan and high efficiency characteristics simultaneously by including the polycyclic compound of one embodiment in the light-emitting layer.

[0307] Although preferred embodiments of the present invention have been described so far with reference, a person skilled in the art or with ordinary knowledge in the art will understand that the present invention can be modified and altered in various ways without departing from the spirit and technical domain of the invention as described in the claims below.

[0308] Therefore, the technical scope of the present invention is not limited to what is described in the detailed description of the specification, but should be determined by the claims. [Explanation of Symbols]

[0309] DD, DD-TD: Display device, ED: Light-emitting element, EL1: First electrode, EL2: Second electrode, HTR: Hole transport region, EML: Light-emitting layer, ETR: Electron transport region

Claims

1. First electrode and, A second electrode is placed on the first electrode, The facility includes a light-emitting layer disposed between the first electrode and the second electrode, which contains a polycyclic compound represented by the following chemical formula 1-1, The first electrode and the second electrode each independently contain at least one selected from Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, In, Sn, and Zn, two or more compounds selected from these, a mixture of two or more selected from these, or an oxide thereof, which is used to create a light-emitting element: 【Chemistry 1】 (Chemical formula 1-1) In the above chemical formula 1-1, X １ ~X ４ These are the same NR b, R b is a substituted or unsubstituted aryl group having 6 to 30 carbon atoms in a ring. a to d are each independent integers between 0 and 4, R 1-R ４ Each of these is independently a hydrogen atom, an unsubstituted alkyl group having 1 to 10 carbon atoms, or an unsubstituted aryl group having 6 to 30 ring-forming carbon atoms. L is L-1 below: 【Chemistry 2】 It is represented as follows.

2. R １ and R ４ The light-emitting element according to claim 1, wherein each is independently a t-butyl group, an unsubstituted phenyl group, or an unsubstituted biphenylyl group.

3. The aforementioned light-emitting layer is a delayed fluorescence light-emitting layer containing a host and a dopant. The light-emitting element according to claim 1, wherein the dopant comprises the polycyclic compound.

4. The light-emitting element according to claim 1, wherein the chemical formula 1-1 is represented by any one of the polycyclic compounds of the following first group of compounds: [First compound group] 【Transformation 3】 。

5. The light-emitting layer comprises a first host, a second host different from the first host, an auxiliary dopant containing an organometallic complex, and a light-emitting dopant. The light-emitting element according to claim 1, wherein the light-emitting dopant comprises the polycyclic compound.

6. The light-emitting element according to claim 5, wherein the first host comprises at least one of the following HT-01 to HT-09 compounds. 【Chemistry 4】 【Transformation 5】 【Transformation 6】

7. The light-emitting element according to claim 5, wherein the second host comprises at least one of the following ET-01 to ET-06 compounds. 【Transformation 7】

8. The light-emitting element according to claim 5, wherein the auxiliary dopant comprises at least one compound from the following compound group P. [Compound group P] 【Transformation 8】 【Chemistry 9】 【Chemistry 10】 【Chemistry 11】

9. The light-emitting element according to claim 1, wherein the light-emitting layer emits blue light having a central wavelength of 450 nm or more and 470 nm or less.

10. The light-emitting element according to claim 1, further comprising a capping layer disposed on the second electrode, wherein the refractive index of the capping layer is 1.6 or greater.

11. First electrode and, A second electrode is placed on the first electrode, The device includes a light-emitting layer disposed between the first electrode and the second electrode, comprising a hole-transporting first host, an electron-transporting second host different from the first host, an auxiliary dopant, and a light-emitting dopant different from the auxiliary dopant. The aforementioned light-emitting dopant is a light-emitting element represented by the following chemical formula 1-1: 【Chemistry 12】 (Chemical formula 1-1) In the above chemical formula 1-1, X １ ~X ４ These are the same NR b, R b is a substituted or unsubstituted aryl group having 6 to 30 carbon atoms in a ring. a to d are each independent integers between 0 and 4, R 1-R ４ Each of these is independently a hydrogen atom, an unsubstituted alkyl group having 1 to 10 carbon atoms, or an unsubstituted aryl group having 6 to 30 ring-forming carbon atoms. L is L-1 below: 【Chemistry 13】 It is represented as follows.

12. The light-emitting element according to claim 11, wherein the chemical formula 1-1 is represented by any one of the polycyclic compounds of the following first group of compounds: [First compound group] 【Chemistry 14】 。

13. Claim that the first host comprises at least one of the following HT-01 to HT-09 compounds. The light-emitting element described in item 11. 【Chemistry 15】 【Chemistry 16】 【Chemistry 17】

14. The light-emitting element according to claim 11, wherein the second host comprises at least one of the following ET-01 to ET-06 compounds. [Chemistry 18]

15. The light-emitting element according to claim 11, wherein the auxiliary dopant comprises at least one compound from the following compound group P. [Compound group P] 【Chemistry 19】 【Chemistry 20】 【Chemistry 21】 【Chemistry 22】

Images