An organic compound, a composition, an organic light emitting element, and a display panel

Abstract

The application discloses an organic compound, a composition, an organic light-emitting element and a display panel. The organic compound has the following chemical structure: The organic compound is applied to the organic light-emitting element as a light extraction layer material, the light extraction efficiency of the organic light-emitting element can be improved, and the light extraction efficiency of the organic light-emitting element can be improved together with an organic compound with a lower refractive index.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to an organic compound, a composition, an organic light-emitting element and a display panel. BACKGROUND

[0002] At present, an organic electroluminescent element generally comprises an anode, a cathode and an organic functional layer between the two, and utilizes the organic substance of the organic functional layer to convert electrical energy into light energy, thereby realizing organic electroluminescence. In order to improve the luminous efficiency and service life of the organic electroluminescent element, the organic functional layer often comprises a multi-layer structure, and the organic substances of each layer are different. Specifically, according to the functional classification, the organic functional layer generally comprises, but is not limited to, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer and an electron injection layer, etc., thereby realizing a large number of commercial electronic device products, and the performance of the organic electroluminescent element has been recognized.

[0003] When the organic electroluminescent element works, by applying a voltage between the anode and the cathode, the anode injects holes into the organic functional layer, and the cathode injects electrons into the organic functional layer. The injected holes and electrons meet to form excitons, and the excitons emit light when they return to the ground state by radiative transition, thereby realizing the light emission of the organic electroluminescent element. However, as time goes by and is exposed to different waveband light, the organic electroluminescent element is long-term in the environment with high-energy ultraviolet light, and the organic substances of each layer may be continuously affected. In order to solve this problem, a light extraction layer with ultraviolet absorption characteristics can generally be used on the organic light-emitting element. In addition, due to the self-luminescence and wide viewing angle characteristics of the light-emitting layer of the organic electroluminescent element, different viewing angles will bring deviations, and the refractive indices of the glass substrate, metal electrode and various organic materials in the organic electroluminescent element do not match the refractive index based on the emission wavelength generated by the light-emitting layer, resulting in low light extraction efficiency. In order to solve this problem, adding a low-refractive-index light extraction layer and a high-refractive-index light extraction layer above the cathode to achieve optical optimization has been considered as one of the effective means to improve the light extraction efficiency.

[0004] Therefore, in order to realize a more stable and efficient organic electroluminescent element, it is urgent to develop a light extraction layer material that meets the high refractive index to avoid the aging of organic materials and improve the light extraction efficiency, thereby improving the service life and luminous efficiency of the organic electroluminescent element. SUMMARY

[0005] The present application provides an organic compound, a composition, an organic light-emitting element and a display panel. The organic compound is applied to the organic light-emitting element as a light extraction layer material, which can improve the light extraction efficiency of the organic light-emitting element, and can also be matched with an organic compound with a lower refractive index to jointly improve the light extraction efficiency of the organic light-emitting element.

[0006] To achieve the above object, according to a first aspect of the present application, there is provided an organic compound having a chemical structure represented by general formula (1):

[0007] (1);

[0008] wherein X1to X 12 are each independently selected from CH, N or CR 1 ;

[0009] L 1 , L 2 and L 3 are each independently selected from at least one of a single bond, a substituted or unsubstituted aromatic group having 6 to 30 ring atoms, and a substituted or unsubstituted heteroaromatic group having 5 to 30 ring atoms;

[0010] n1, n2 and n3 are each an integer selected from 1 to 4;

[0011] Ar 1 and Ar 2 are each independently selected from any one of the following groups:

[0012] ;

[0013] X is selected from O or S;

[0014] Y is selected from N or CR 4 ;

[0015] Y1to Y4are each independently selected from CH, N or CR 5 ;

[0016] Ar 1 and Ar 2 , wherein ring A is fused to any available position of the benzene ring, and ring A is selected from at least one of a substituted or unsubstituted aromatic group having 6 to 30 ring atoms, and a substituted or unsubstituted heteroaromatic group having 5 to 30 ring atoms;

[0017] R 1 to R 5at least one of H, D, a straight-chain alkyl group having 1 to 20 C atoms, a straight-chain alkoxy group having 1 to 20 C atoms, a straight-chain thioalkoxy group having 1 to 20 C atoms, a branched or cyclic alkyl group having 3 to 20 C atoms, a branched or cyclic alkoxy group having 3 to 20 C atoms, a branched or cyclic thioalkoxy group having 3 to 20 C atoms, a silyl group, a keto group having 1 to 20 C atoms, an alkoxycarbonyl group having 2 to 20 C atoms, an aryloxycarbonyl group having 7 to 20 C atoms, a cyano group, a carbamoyl group, a halogen formyl group, a formyl group, an isocyano group, an isocyanate group, a thiocyanate group, an isothiocyanate, a hydroxyl group, a nitro group, CF3, Cl, Br, F, a substituted or unsubstituted aromatic group having 5 to 60 ring atoms, a substituted or unsubstituted heteroaromatic group having 5 to 60 ring atoms, an aryloxy group having 5 to 60 ring atoms, a heteroaryloxy group having 5 to 60 ring atoms;

[0018] " indicates a connection site. " indicates a connection site.

[0019] According to a second aspect of the present application, there is provided a composition including at least one organic solvent and at least one organic compound described above.

[0020] According to a third aspect of the present application, there is provided an organic light emitting element including:

[0021] a first electrode;

[0022] a second electrode disposed opposite to the first electrode;

[0023] an organic functional layer between the first electrode and the second electrode;

[0024] a light extraction layer on a side of the first electrode away from the organic functional layer, or on a side of the second electrode away from the organic functional layer;

[0025] wherein a material of the light extraction layer includes at least one of the organic compounds described above, or the light extraction layer is made of the composition described above.

[0026] According to a fourth aspect of the present application, there is provided a display panel including the organic light emitting element described above.

[0027] The organic compound, the composition, the organic light-emitting element and the display panel provided by the application have high refractive index, and the organic compound can be used as a light extraction layer material with high refractive index, and can be applied to a light extraction layer of an organic light-emitting element in combination with a light extraction layer material with low refractive index, so that the microcavity effect can be enhanced, and the light extraction efficiency of the organic light-emitting element is improved. Specifically, in the molecular structure, the organic compound provided by the application uses a benzanthracene group in combination with a tertiary amine skeleton and a small heteroatom condensed ring group, and the conjugated system obtained by the combination brings high polarizability by virtue of delocalized π electrons, so that the electron cloud is easy to be distorted, thereby bringing the characteristics of high refractive index. At the same time, the chemical structure of the organic compound provided by the application has certain molecular rigidity and takes into account high planarity, which can further amplify the polarization effect and maintain its stability. In summary, when the organic compound represented by the general formula (1) provided by the application is used as a light extraction layer material, especially as a light extraction layer material with high refractive index, the high refractive index advantage of the organic compound can be effectively utilized to improve the light extraction efficiency of the organic light-emitting element, thereby improving the service life and luminous efficiency of the organic light-emitting element. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0029] Figure 1 is a structural schematic diagram of an organic light-emitting element provided by an embodiment of the application;

[0030] Figure 2 is a mass spectrum diagram of a compound P-1 synthesized by an embodiment of the application;

[0031] Figure 3 is a mass spectrum diagram of a compound P-26 synthesized by an embodiment of the application;

[0032] Figure 4 is a refractive index curve diagram of a compound P-26 synthesized by an embodiment of the application and a comparative compound REF01.

[0033] The drawings are described as follows: 100, an organic light-emitting element; 1, a substrate; 11, a first electrode; 12, a hole injection layer; 13, a hole transport layer; 14, a light-emitting auxiliary layer; 15, an organic light-emitting layer; 16, an electron transport layer; 17, an electron injection layer; 18, a second electrode; 19, a light extraction layer; 191, a first sub-light extraction layer; 192, a second sub-light extraction layer. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0035] In the present application, the aromatic group, the aromatic, the aromatic ring system have the same meaning and can be interchangeable.

[0036] In the present application, the heteroaromatic group, the heteroaromatic, the heteroaromatic ring system have the same meaning and can be interchangeable.

[0037] In the present application, "substituted" means that the hydrogen atom in the substituent is replaced by the substituent.

[0038] In the present application, when the same substituent appears multiple times, it can be independently selected from different groups. For example, if the general formula contains multiple R, R can be independently selected from different groups.

[0039] In the present application, "substituted or unsubstituted" means that the defined group can be substituted or unsubstituted. When the defined group is substituted, it is understood that the defined group can be substituted by one or more substituents R, which is selected from but not limited to: deuterium atom, cyano, isocyano, nitro or halogen, alkyl group containing 1-20 carbon atoms, heterocyclic group containing 3-20 ring atoms, aromatic group containing 6-20 ring atoms, heteroaromatic group containing 5-20 ring atoms, -NR'R'', silyl group, carbonyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, halogen formyl group, formyl group, isocyanate group, thiocyanate group, isothiocyanate group, hydroxyl group, trifluoromethyl group, and the above-mentioned groups can also be further substituted by acceptable substituents in the art; it can be understood that R' and R'' in -NR'R'' are independently selected from but not limited to: H, deuterium atom, cyano, isocyano, nitro or halogen, alkyl group containing 1-10 carbon atoms, heterocyclic group containing 3-20 ring atoms, aromatic group containing 6-20 ring atoms, heteroaromatic group containing 5-20 ring atoms. Preferably, R is selected from but not limited to: deuterium atom, cyano, isocyano, nitro or halogen, alkyl group containing 1-10 carbon atoms, heterocyclic group containing 3-10 ring atoms, aromatic group containing 6-20 ring atoms, heteroaromatic group containing 5-20 ring atoms, silyl group, carbonyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, halogen formyl group, formyl group, isocyanate group, thiocyanate group, isothiocyanate group, hydroxyl group, trifluoromethyl group, and the above-mentioned groups can also be further substituted by acceptable substituents in the art.

[0040] In the present application, the "number of ring atoms" means the number of atoms among atoms constituting a ring itself of a structural compound (e.g., monocyclic compound, fused ring compound, crosslinked compound, carbocyclic compound, heterocyclic compound) obtained by bonding atoms into a ring. When the ring is substituted with a substituent, atoms included in the substituent are not included in the ring-forming atoms. The same is true for the "number of ring atoms" described below, unless otherwise specified. For example, the number of ring atoms of a benzene ring is 6, the number of ring atoms of a naphthalene ring is 10, and the number of ring atoms of a thiophene group is 5.

[0041] In the present application, "aryl group" or "aromatic group" means an aromatic hydrocarbon group derived by removing one hydrogen atom from an aromatic ring compound, and can be a monocyclic aryl group, or a fused ring aryl group, or a polycyclic aryl group, and at least one of the rings in the polycyclic ring is an aromatic ring system. For example, "substituted or unsubstituted aryl group having 6 to 40 ring atoms" means an aryl group having 6 to 40 ring atoms, preferably a substituted or unsubstituted aryl group having 6 to 30 ring atoms, more preferably a substituted or unsubstituted aryl group having 6 to 18 ring atoms, particularly preferably a substituted or unsubstituted aryl group having 6 to 14 ring atoms, and the aryl group is optionally further substituted; suitable examples include, but are not limited to, phenyl, biphenyl, terphenyl, naphthyl, anthryl, phenanthryl, fluoranthenyl, pyrenyl, chrysenyl, tetracenyl, fluorenyl, perylenyl, acenaphthenyl, and derivatives thereof. It is understood that multiple aryl groups can also be interrupted by short non-aromatic units (e.g., <10% non-H atoms such as C, N, or O atoms), specifically such as acenaphthene, fluorene, or 9,9'-diarylfluorene, triarylamine, diaryl ether systems should also be included in the definition of aryl group.

[0042] In the present application, "heteroaryl or heteroaromatic group" means that at least one carbon atom of an aryl group is replaced by a non-carbon atom, which can be an N atom, an O atom, an S atom, etc. For example, "substituted or unsubstituted heteroaryl group having 5 to 40 ring atoms" means a heteroaryl group having 5 to 40 ring atoms, preferably a substituted or unsubstituted heteroaryl group having 6 to 30 ring atoms, more preferably a substituted or unsubstituted heteroaryl group having 6 to 18 ring atoms, particularly preferably a substituted or unsubstituted heteroaryl group having 6 to 14 ring atoms, and the heteroaryl group is optionally further substituted, and suitable examples include, but are not limited to, thienyl, furanyl, pyrrolyl, imidazolyl, oxadiazolyl, triazolyl, imidazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, acridinyl, pyridazinyl, pyrazinyl, quinolinyl, isoquinolinyl, quinazolinyl, quinoxalinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, benzothienyl, benzofuranyl, indolyl, pyrroloimidazolyl, pyrrolopyrrolyl, thienopyrrolyl, thienothienyl, furanopyrrolyl, furanofuranyl, thienofuranyl, benzisoxazolyl, benzisothiazolyl, benzimidazolyl, perylenyl, phenanthridinyl, berberinyl, quinazolinonyl, dibenzothienyl, dibenzofuranyl, carbazolyl, and derivatives thereof.

[0043] In the present application, "alkyl" can mean straight chain, branched chain, and / or cyclic alkyl. The number of carbons of the alkyl group can be 1 to 50, 1 to 30, 1 to 20, 1 to 10, or 1 to 6. The phrase including this term, for example, "C1-6 alkyl" means an alkyl group having 1 to 6 carbons. 1-9"Alkyl" refers to an alkyl group containing from 1 to 9 carbon atoms, which can be Ci alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl, C7 alkyl, C8 alkyl, or C9 alkyl, each occurrence of which is independent of the other and is optionally substituted. Non-limiting examples of alkyl groups include methyl, ethyl, n-propyl, i-propyl, 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, 2-ethylhexyl, 2-butylhexyl, cyclohexyl, 4-methylcyclohexyl, 4-t-butylcyclohexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, t-octyl, 2-ethyloctyl, 2-butyl-octyl, 2-hexyl-octyl, 3,7-dimethyloctyl, cyclooctyl, n-nonyl, n-decyl, adamantyl, 2-ethyldecyl, 2-butyldecyl, 2-hexyldecyl, 2-octyldecyl, n-undecyl, n-dodecyl, 2-ethyldodecyl, 2-butyl-dodecyl, 2-hexyl-dodecyl, 2-octyl-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, 2-ethylhexadecyl, 2-butylhexadecyl, 2-hexylhexadecyl, 2-octylhexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, 2-ethyleicosyl, 2-butyleicosyl, 2-hexyleicosyl, 2-octyleicosyl, n- heneicosyl, n-docosyl, n-tricosyl, n-tetracosyl, n-pentacosyl, n-hexacosyl, n-heptacosyl, n-octacosyl, n-nonacosyl, n-triacontyl, and the like.

[0044] In the present application, "amine group" refers to derivatives of amines, having the structural feature of the formula -N(X)2, wherein each "X" is independently H, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocyclyl, and the like. Non-limiting types of amine groups include -NH2, -N(alkyl)2, -NH(alkyl), -N(cycloalkyl)2, -NH(cycloalkyl), -N(heterocyclyl)2, -NH(heterocyclyl), -N(aryl)2, -NH(aryl), -N(alkyl)(aryl), -N(alkyl)(heterocyclyl), -N(cycloalkyl)(heterocyclyl), -N(aryl)(heteroaryl), -N(alkyl)(heteroaryl), and the like.

[0045] In the present application, unless specifically defined, hydroxy refers to -OH, carboxy refers to -COOH, carbonyl refers to -C(=O)-, amino refers to -NH2, formyl refers to -C(=O)H, halogen formyl refers to -C(=O)Z (wherein Z represents halogen), carbamoyl refers to -C(=O)NH2, isocyanate refers to -NCO, and isothiocyanate refers to -NCS.

[0046] In the present application, the term "alkoxy" refers to a group of structure "-O-alkyl", i.e. an alkyl group as defined above is attached to other groups via an oxygen atom. Suitable examples of the phrase comprising this term include, but are not limited to: methoxy (-O-CH3or -OMe), ethoxy (-O-CH2CH3or -OEt) and tert-butoxy (-O-C(CH3)3or -OtBu).

[0047] In the present application, "attached or fused site" of "attached or fused to" means the site of the group to which the other group is attached or fused. In the present application, "attached or fused site" of "attached or fused to" means the site of the group to which the other group is attached or fused.

[0048] In the present application, when the attachment site is not specified in a group, it means that any optional attachment site in the group is the attachment site.

[0049] In the present application, when the fused site is not specified in a group, it means that any optional fused site in the group is the fused site, preferably two or more sites in the ortho position of the group are the fused sites.

[0050] In the present application, when there are multiple substituents with the same symbol on the same group, each substituent can be the same as or different from each other, for example , the 6 R on the benzene ring can be the same as or different from each other.

[0051] In the present application, the single bond to which the substituent is attached runs through the corresponding ring, which means that the substituent can be attached to any optional position of the ring, for example , R is attached to any substitutable site of the benzene ring; for example , R is attached to any substitutable site of the benzene ring. , R is attached to any substitutable site of the benzene ring. , R is attached to any substitutable site of the benzene ring.

[0052] The cyclic alkyl or cycloalkyl according to the present application have the same meaning and can be interchangeable.

[0053] The present application provides an organic compound, which has a chemical structure represented by general formula (1):

[0054] (1);

[0055] X1to X 12 are each independently selected from CH, N or CR 1 ;

[0056] L 1 , L 2 and L 3 are each independently selected from at least one of a single bond, a substituted or unsubstituted aromatic group having 6 to 30 ring atoms, and a substituted or unsubstituted heteroaromatic group having 5 to 30 ring atoms;

[0057] n1, n2 and n3 are selected from any one of integers from 1 to 4;

[0058] Ar 1 and Ar 2 are each independently selected from any one of the following groups:

[0059] ;

[0060] X is selected from O or S;

[0061] Y is selected from N or CR 4 ;

[0062] Y1 to Y4 are each independently selected from CH, N or CR 5 ;

[0063] Ar 1 and Ar 2 , wherein ring A is fused to any available position of the benzene ring, and ring A is selected from at least one of a substituted or unsubstituted aromatic group having 6 to 30 ring atoms, a substituted or unsubstituted heteroaromatic group having 5 to 30 ring atoms;

[0064] R 1 to R 5 are each independently selected from at least one of H, D, a straight-chain alkyl group having 1 to 20 C atoms, a straight-chain alkoxy group having 1 to 20 C atoms, a straight-chain thioalkoxy group having 1 to 20 C atoms, a branched or cyclic alkyl group having 3 to 20 C atoms, a branched or cyclic alkoxy group having 3 to 20 C atoms, a branched or cyclic thioalkoxy group having 3 to 20 C atoms, a silyl group, a keto group having 1 to 20 C atoms, an alkoxycarbonyl group having 2 to 20 C atoms, an aryloxycarbonyl group having 7 to 20 C atoms, a cyano group, a carbamoyl group, a halogen formyl group, a formyl group, an isocyano group, an isocyanate group, a thiocyanate group, an isothiocyanate, a hydroxyl group, a nitro group, CF3, Cl, Br, F, a substituted or unsubstituted aromatic group having 5 to 60 ring atoms, a substituted or unsubstituted heteroaromatic group having 5 to 60 ring atoms, an aryloxy group having 5 to 60 ring atoms, a heteroaryloxy group having 5 to 60 ring atoms;

[0065] " indicates a connection site. " indicates a connection site.

[0066] In some embodiments, the organic compound is selected from any one of the compounds represented by general formula (2), general formula (3), general formula (4) and general formula (5):

[0067]

[0068] .

[0069] In some embodiments, L 1 L 2 and L 3 Each of the following is independently selected from at least one of a single bond, phenylene, biphenylene, naphthylene, dibenzofuranylene, and dibenzothiopheneylene.

[0070] In some embodiments, Ar 1 and Ar 2 Each group is independently selected from any one of the following groups:

[0071]

[0072]

[0073]

[0074] ;

[0075] Among them, Ar 1 and Ar 2 The H on the cyclic group is not substituted or at least one H is replaced by R. 5 replace.

[0076] In some embodiments, the film composed of the organic compound has a refractive index greater than 1.99 for light with a wavelength of 630 nm. Therefore, the organic compound can be used to fabricate high refractive index films.

[0077] In some embodiments, the organic compound is selected from, but is not limited to, any one of the following compounds:

[0078]

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[0276] It should be noted that the H atoms in the organic compounds listed above can be arbitrarily substituted, particularly with deuterium (D) atoms. Deuteration of the H atoms in these organic compounds improves their stability.

[0277] The organic compounds provided in this application embodiment can be used as functional materials in the functional layers of organic light-emitting elements. These functional layers include, but are not limited to, hole injection layer (HIL), hole transport layer (HTL), electron injection layer (EIL), electron transport layer (ETL), prime layer, hole blocking layer (HBL), light extraction layer (CPL), and emissive layer (EML).

[0278] In some embodiments, the organic compounds provided in this application are applied to the light extraction layer of an organic light-emitting element.

[0279] In some embodiments, the organic compound represented by general formula (1) has a refractive index greater than 1.99 for light with a wavelength of 630 nm. In a preferred embodiment, the organic compound represented by general formula (1) has a refractive index greater than 2.08 for light with a wavelength of 630 nm. In a more preferred embodiment, the organic compound represented by general formula (1) has a refractive index greater than 2.14 for light with a wavelength of 630 nm. It is understood that the organic compound represented by general formula (1) has a high refractive index for visible light.

[0280] When the organic compounds provided in the embodiments of this application are applied in vapor-deposited OLED devices, the molecular weight of the organic compound represented by general formula (1) is ≤1200 g / mol. In some preferred embodiments, the molecular weight of the organic compound represented by general formula (1) is ≤1100 g / mol. In some more preferred embodiments, the molecular weight of the organic compound represented by general formula (1) is ≤1000 g / mol. In some even more preferred embodiments, the molecular weight of the organic compound represented by general formula (1) is ≤950 g / mol. In some most preferred embodiments, the molecular weight of the organic compound represented by general formula (1) is ≤900 g / mol.

[0281] This application also provides a composition comprising at least one first organic solvent and at least one of the above-described organic compounds. The first organic solvent is selected from at least one of aromatic or heteroaromatic compounds, esters, aromatic ketones or aromatic ethers, aliphatic ketones or aliphatic ethers, alicyclic or olefinic compounds, borate esters or phosphate esters.

[0282] In some embodiments, the first organic solvent is selected from aromatic or heteroaromatic solvents.

[0283] Examples of aromatic or heteroaromatic solvents suitable for this application include, but are not limited to: p-diisopropylbenzene, pentobenzene, tetrahydronaphthalene, cyclohexylbenzene, chloronaphthalene, 1,4-dimethylnaphthalene, 3-isopropylbiphenyl, p-methylisopropylbenzene, dipentylbenzene, tripentylbenzene, pentylene, o-diethylbenzene, m-diethylbenzene, p-diethylbenzene, 1,2,3,4-tetramethylbenzene, 1,2,3,5-tetramethylbenzene, 1,2,4,5-tetramethylbenzene, butylbenzene, dodecylbenzene, dihexylbenzene, dibutylbenzene, p-diisopropylbenzene, cyclohexylbenzene, benzylbutylbenzene Dimethylnaphthalene, 3-isopropylbiphenyl, p-methylisopropylbenzene, 1-methylnaphthalene, 1,2,4-trichlorobenzene, 4,4-difluorodiphenylmethane, 1,2-dimethoxy-4-(1-propenyl)benzene, diphenylmethane, 2-phenylpyridine, 3-phenylpyridine, N-methyldiphenylamine, 4-isopropylbiphenyl, 4-(3-phenylpropyl)pyridine, benzyl benzoate, 1,1-bis(3,4-dimethylphenyl)ethane, 2-isopropylnaphthalene, quinoline, isoquinoline, methyl 2-furanoate, ethyl 2-furanoate, etc.

[0284] Examples of aromatic ketone-based solvents suitable for this application include, but are not limited to: 1-tetrahydronaphthone, 2-tetrahydronaphthone, 2-(phenylepoxy)tetrahydronaphthone, 6-(methoxy)tetrahydronaphthone, acetophenone, phenylacetone, benzophenone, and their derivatives, such as 4-methylacetophenone, 3-methylacetophenone, 2-methylacetophenone, 4-methylphenylacetone, 3-methylphenylacetone, 2-methylphenylacetone, etc.

[0285] Examples of aromatic ether-based solvents suitable for this application include, but are not limited to: 3-phenoxytoluene, butoxybenzene, p-anisaldehyde dimethyl acetal, tetrahydro-2-phenoxy-2H-pyran, 1,2-dimethoxy-4-(1-propenyl)benzene, 1,4-benzodioxane, 1,3-dipropylbenzene, 2,5-dimethoxytoluene, 4-ethylbenzene, 1,3-dipropoxybenzene, 1,2,4-trimethoxybenzene, 4-(1-propenyl)-1,2-dimethoxybenzene, 1,3-dimethoxybenzene, glycidylphenyl ether, dibenzyl ether, 4-tert-butylanisole, trans-p-propenylanisole, 1,2-dimethoxybenzene, 1-methoxynaphthalene, diphenyl ether, 2-phenoxymethyl ether, 2-phenoxytetrahydrofuran, ethyl-2-naphthyl ether.

[0286] Examples of aliphatic ketone-based solvents suitable for this application include, but are not limited to: 2-nonanone, 3-nonanone, 5-nonanone, 2-decanone, 2,5-hexanedione, 2,6,8-trimethyl-4-nonanone, frankinc, phorone, isophorone, di-n-pentyl ketone, etc.; or aliphatic ethers, such as pentyl ether, hexyl ether, dioctyl ether, ethylene glycol dibutyl ether, diethylene glycol diethyl ether, diethylene glycol butyl methyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, triethylene glycol ethyl methyl ether, triethylene glycol butyl methyl ether, tripropylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, etc.

[0287] Examples of ester-based solvents suitable for this application include, but are not limited to: alkyl octanoate, alkyl sebacate, alkyl stearate, alkyl benzoate, alkyl phenylacetate, alkyl cinnamate, alkyl oxalate, alkyl maleate, alkyl lactone, alkyl oleate, etc. Octyl octanoate, diethyl sebacate, diallyl phthalate, and isononyl isononanoate are particularly preferred.

[0288] In some embodiments, the composition further comprises a second organic solvent selected from at least one of methanol, ethanol, 2-methoxyethanol, dichloromethane, trichloromethane, chlorobenzene, o-dichlorobenzene, tetrahydrofuran, anisole, morpholine, toluene, o-xylene, m-xylene, p-xylene, 1,4-dioxane, acetone, methyl ethyl ketone, 1,2-dichloroethane, 3-phenoxytoluene, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, ethyl acetate, butyl acetate, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, tetrahydronaphthalene, naphthane, and indene.

[0289] In some embodiments, solvents particularly suitable for this application are those with Hansen solubility parameters within the following ranges:

[0290] δd (dispersion force) is in the range of 17.0~23.2 MPa. 1 / 2 The range, especially in the 18.5~21.0 MPa range. 1 / 2 Scope;

[0291] δp (polar force) is in the range of 0.2~12.5 MPa. 1 / 2 The range, especially 2.0~6.0 MPa 1 / 2 Scope;

[0292] δh (hydrogen bond force) ranges from 0.9 to 14.2 MPa. 1 / 2 The range, especially 2.0~6.0 MPa 1 / 2 The range.

[0293] The selection of the organic solvent in the composition must take into account its boiling point. In this application, the boiling point of the organic solvent is ≥150°C; preferably ≥180°C; more preferably ≥200°C; even more preferably ≥250°C; and most preferably ≥275°C or ≥300°C. Boiling points within these ranges are beneficial for preventing nozzle clogging of the inkjet printhead. The organic solvent can evaporate from the solvent system to form a thin film containing functional materials.

[0294] In some embodiments, the composition is a solution.

[0295] In other embodiments, the composition is a suspension.

[0296] In this application, the composition may include 0.01% to 20% by mass of the organic compound or the mixture. Further, the organic compound or the mixture has a mass fraction of 0.1% to 15% in the composition. Preferably, the organic compound or the mixture has a mass fraction of 0.2% to 10% in the composition.

[0297] For example, the organic compound in the composition is 0.01%, 0.05%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 3%, 5%, 8%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, or 20% by mass.

[0298] The composition provided in this application can be used as a coating or printing ink to prepare organic light-emitting elements. In particular, it is preferred that the composition can be used as a coating or printing ink to prepare organic light-emitting elements by printing or coating methods.

[0299] Suitable printing or coating technologies include (but are not limited to) inkjet printing, nozzle printing, letterpress printing, screen printing, dip coating, spin coating, doctor blade coating, roller printing, torsional roller printing, offset printing, flexographic printing, rotary printing, spraying, brushing or pad printing, and slot-fitting coating. Gravure printing, inkjet printing, and gravure printing are preferred. The solution or suspension may additionally include one or more components such as surfactants, lubricants, wetting agents, dispersants, hydrophobic agents, and binders to adjust viscosity, film-forming properties, and improve adhesion. The printing technology and its related requirements for the solution, such as solvent and concentration, viscosity, etc., are also important considerations.

[0300] like Figure 1 As shown in the illustration, this application also provides an organic light-emitting element 100, which includes a first electrode 11, a second electrode 18, an organic functional layer, and a light extraction layer 19. The second electrode 18 is disposed opposite to the first electrode 11. The organic functional layer is located between the first electrode 11 and the second electrode 18. The light extraction layer 19 is located on the side of the first electrode 11 away from the organic functional layer, or on the side of the second electrode 18 away from the organic functional layer. The material of the light extraction layer 19 includes at least one of the organic compounds described in the foregoing embodiments, or the light extraction layer 19 is made using the composition described in the foregoing embodiments.

[0301] Specifically, the organic light-emitting element 100 includes, but is not limited to, organic light-emitting diodes (OLEDs), organic photovoltaic cells (OPVs), organic light-emitting electrochemical cells (OLEECs), organic field-effect transistors (OFETs), organic light-emitting field-effect transistors (OLEFETs), organic lasers, organic spintronic devices, organic sensors, and organic plasmon emission diodes (OPEDs). Particularly preferred are organic electroluminescent devices, such as OLEDs, OLEECs, or OLEFETs.

[0302] In some embodiments, the light extraction layer 19 includes a first sub-light extraction layer 191 and a second sub-light extraction layer 192 stacked together, the second sub-light extraction layer 192 being located on the side of the first sub-light extraction layer 191 away from the organic functional layer. The refractive index of the second sub-light extraction layer 192 is greater than the refractive index of the first sub-light extraction layer 191, and the material of the second sub-light extraction layer 192 includes at least one of the organic compounds.

[0303] Understandably, the first sub-light extraction layer 191 is a low-refractive-index film layer, and the second sub-light extraction layer 192 is a high-refractive-index film layer; the second sub-light extraction layer 192 is prepared using the aforementioned organic compound or composition. In this embodiment, the refractive indices of the first sub-light extraction layer 191 and the second sub-light extraction layer 192 are matched to effectively improve the light extraction efficiency of the organic light-emitting element 100.

[0304] In some embodiments, the refractive index of the second sub-light extraction layer 192 for light with a wavelength of 630 nm is greater than 1.99. In a preferred embodiment, the refractive index of the second sub-light extraction layer 192 for light with a wavelength of 630 nm is greater than 2.08. In a more preferred embodiment, the refractive index of the second sub-light extraction layer 192 for light with a wavelength of 630 nm is greater than 2.14.

[0305] In some embodiments, the first electrode 11 is an anode and the second electrode 18 is a cathode, but this is not a limitation. This application embodiment illustrates an example where the light extraction layer 19 is disposed on the side of the second electrode 18 away from the organic functional layer.

[0306] In some embodiments, such as Figure 1 As shown, the organic functional layer sandwiched between the first electrode 11 and the second electrode 18 includes, but is not limited to, a hole injection layer 12, a hole transport layer 13, a light-emitting auxiliary layer 14, an organic light-emitting layer 15, an electron transport layer 16 and an electron injection layer 17 sequentially disposed on one side of the first electrode 11.

[0307] In some embodiments, the organic light-emitting element 100 further includes a substrate 1, and a first electrode 11 is disposed on the substrate 1. The substrate 1 may be an array substrate for providing a driving voltage to the first electrode and the second electrode to drive the organic light-emitting layer to emit light, but is not limited thereto.

[0308] In some embodiments, the organic light-emitting element 100 is an OLED device, specifically including a substrate 1, an anode (i.e., a first electrode 11), at least one organic light-emitting layer 15, a cathode (i.e., a second electrode 18), and a light extraction layer 19.

[0309] The substrate 1 can be opaque or transparent. A transparent substrate 1 can be used to fabricate a transparent organic light-emitting element. See, for example, Bulovic et al., Nature 1996, 380, p29, and Gu et al., Appl. Phys. Lett. 1996, 68, p2606. The substrate 1 can be rigid or flexible. The substrate 1 can be plastic, metal, semiconductor wafer, or glass. Preferably, the substrate 1 has a smooth surface. A substrate without surface defects is particularly desirable. In a preferred example, the substrate 1 is flexible and can be a polymer film or plastic with a glass transition temperature (Tg) of 150°C or higher, preferably 200°C or higher, more preferably 250°C or higher, and most preferably 300°C or higher. Examples of suitable flexible substrates include polyethylene terephthalate (PET) and polyethylene glycol (2,6-naphthalene) (PEN).

[0310] The anode may comprise a conductive metal, metal oxide, or conductive polymer. Holes can be readily injected into the HIL, HTL, or EML. In one example, the absolute value of the difference between the work function of the anode and the HOMO level or valence band level of the light emitter in the organic light-emitting layer or the p-type semiconductor material of the HIL, HTL, or EBL is less than 0.5 eV, preferably less than 0.3 eV, and most preferably less than 0.2 eV. Examples of anode materials include, but are not limited to, Al, Cu, Au, Ag, Mg, Fe, Co, Ni, Mn, Pd, Pt, ITO, aluminum-doped zinc oxide, etc. Other suitable anode materials are known and can be readily selected by those skilled in the art. The anode material can be deposited using any suitable technique, such as a suitable physical vapor deposition method, including radio frequency magnetron sputtering, vacuum thermal evaporation, electron beam deposition, etc. In some embodiments, the anode is patterned. Patterned ITO conductive substrates are commercially available and can be used to fabricate the organic light-emitting element.

[0311] The cathode comprises a conductive metal or metal oxide. Electrons can be readily injected into the EIL or ETL or directly into the organic light-emitting layer. In one embodiment, the absolute value of the difference between the work function of the cathode and the LUMO level or conduction band level of the light-emitting element or the n-type semiconductor material serving as the EIL, ETL, or HBL is less than 0.5 eV, preferably less than 0.3 eV, and most preferably less than 0.2 eV. In principle, all materials suitable for use as cathodes in OLEDs can be used as cathode materials for the devices of this application. Examples of cathode materials include, but are not limited to: Al, Au, Ag, Ca, Ba, Mg, LiF / Al, MgAg alloy, BaF2 / Al, Cu, Fe, Co, Ni, Mn, Pd, Pt, ITO, etc. The cathode material can be deposited using any suitable technique, such as a suitable physical vapor deposition method, including radio frequency magnetron sputtering, vacuum thermal evaporation, electron beam deposition, etc.

[0312] The light extraction layer 19 has a suitable energy level structure, exhibiting strong absorption in the region with wavelengths less than 400 nm (ultraviolet band) and weak or near-zero absorption in the visible light band with wavelengths greater than 400 nm. This can prevent damage to the internal materials of the device from high-energy light irradiation during subsequent processes. Simultaneously, the light extraction layer 19 has a high refractive index, enabling beneficial extraction of visible light emission, thereby improving the luminous efficiency of the organic light-emitting element 100.

[0313] When the reflectivity of the interface between the light extraction layer 19 and the adjacent electrode (e.g., the second electrode 18) is high, the effect of light interference is significant. Therefore, the refractive index of the material constituting the light extraction layer is preferably greater than that of the adjacent electrode. The refractive index of the light extraction layer material for light with a wavelength of 630 nm is generally greater than or equal to 1.50. In a preferred embodiment, the refractive index of the light extraction layer material for light with a wavelength of 630 nm is greater than or equal to 1.70. In a particularly preferred embodiment, the refractive index of the light extraction layer material for light with a wavelength of 630 nm is greater than or equal to 1.80.

[0314] In some embodiments, the thickness of the second sub-light extraction layer 192 ranges from 10 nm to 200 nm. In a preferred embodiment, the thickness of the second sub-light extraction layer 192 ranges from 20 nm to 150 nm. In a more preferred embodiment, the thickness of the second sub-light extraction layer 192 ranges from 30 nm to 100 nm. In a most preferred embodiment, the thickness of the second sub-light extraction layer 192 ranges from 40 nm to 90 nm. Conversely, in some embodiments, the thickness of the light extraction layer 19 is 4 to 8 times the thickness of the cathode.

[0315] In some embodiments, the emission wavelength of the organic light-emitting element 100 is between 300 nm and 1000 nm, preferably between 350 nm and 900 nm, and more preferably between 400 nm and 800 nm.

[0316] The organic light-emitting element provided in this application embodiment can be applied in electronic devices, including but not limited to display devices, lighting devices, light sources, sensors, etc.

[0317] This application embodiment also provides a display panel, which includes the organic light-emitting elements described above.

[0318] The present application will now be described in conjunction with preferred embodiments, but the scope of protection of the present application is not limited to the following embodiments. It should be understood that the appended claims summarize the scope of protection of the present application. Under the guidance of the concept of the present application, those skilled in the art should realize that any changes made to the various embodiments of the present application will be covered by the spirit and scope of the claims of the present application. Specific Implementation

[0320] The organic compounds and their preparation methods described in this application are further illustrated below with reference to specific embodiments. Unless otherwise specified, all raw materials used in the following embodiments are commercially available products.

[0321] (I) Examples of Organic Compound Synthesis

[0322] Example 1

[0323] The synthetic route for compound P-1 is as follows:

[0324] .

[0325] Weigh reactant A (0.1 mol) and reactant B (0.1 mol) into a clean three-necked flask, and add Pd132 (1.0 mmol), X-Phos (2.0 mmol), and sodium tert-butoxide (0.2 mol) dissolved in toluene. Replace the nitrogen atmosphere three times, heat the reaction solution to 100°C under nitrogen atmosphere, and reflux for 12 h. After the reaction solution cools naturally, wash with water and separate the liquid. Dry the organic phase obtained by separation, evaporate to dryness, and then perform column chromatography to obtain compound P-1 with a yield of 89%.

[0326] Electrospray ionization mass spectrometry (ESI-MS) results of compound P-1: m / z [H + [=662, the mass spectrum of the product obtained according to the above synthetic route and preparation process is as follows] Figure 2As shown, the theoretical elemental analysis of the product by inductively coupled plasma (ICP) testing is C, 79.85; H, 4.11; N, 6.35; S, 9.69, while the measured values ​​are C, 79.8; H, 4.1; N, 6.4; S, 9.7, thus proving that the obtained product is compound P-1.

[0327] Examples 2 to 34

[0328] Following the preparation method of compound P-1 in Example 1, compounds P-1 to P-34 in Table 1 were prepared using the reactants shown in Table 1. In Table 1, the "serial number" indicates the number of the synthesis example.

[0329] Table 1. Information on reactants and products in Examples 1-34

[0330]

[0331] Among them, the electrospray ionization mass spectrometry (ESI-MS) results for compound P-26 are: m / z [H + [=706], the mass spectrum of the product obtained according to the above synthetic route and preparation process is as follows: Figure 3 As shown, the theoretical values ​​of the product obtained by inductively coupled plasma (ICP) elemental analysis are C, 85.09; H, 4.43; N, 5.95; O, 4.53, while the measured values ​​are C, 85.1; H, 4.4; N, 6.0; O, 4.5. This proves that the obtained product is compound P-26.

[0332] Comparative Examples 1-4

[0333] This application also provides Comparative Examples 1 to 4, and the comparative compounds provided in Comparative Examples 1 to 4 are respectively designated as "REF01" to "REF04", and their chemical structural formulas are shown below:

[0334] .

[0335] Following the preparation method of compound P-1 in Example 1, the comparative compounds REF01 to REF04 in Table 2 were prepared using the reactant raw materials shown in Table 2. In Table 2, "Serial Number" indicates the number of the comparative example.

[0336] Table 2. Information on reactants and products in Comparative Examples 1-4

[0337]

[0338] (ii) Refractive index testing of compounds

[0339] The compounds provided in Examples 1-34 and the comparative compounds provided in Comparative Examples 1-4 of this application were independently deposited onto single-crystal silicon using vacuum evaporation to form 80 nm thick films. The single-crystal silicon was then placed on an ellipsometer sample stage with an incident angle of 70°. The refractive indices of the films at wavelengths of 460 nm, 530 nm, and 620 nm were measured using an ellipsometer and denoted as n@460 nm, n@530 nm, and n@620 nm, respectively. Simultaneously, the differences Δn1 between the refractive indices at 460 nm and 530 nm, Δn2 between the refractive indices at 530 nm and 620 nm, and Δn3 between the refractive indices at 460 nm and 620 nm were calculated. The test and calculation results are shown in Table 3.

[0340] Understandably, the refractive index of a thin film deposited on monocrystalline silicon is equivalent to the refractive index of the corresponding compound.

[0341] Table 3 Refractive indices of the compounds provided in the examples and comparative examples

[0342]

[0343] As shown in Table 3, the refractive index of compounds P-1 to P-34 provided in the embodiments of this application is not less than 2.0 at a wavelength of 620 nm, indicating that these compounds have high refractive indices. Meanwhile, the difference between the refractive indices of compounds P-1 to P-34 at a wavelength of 460 nm and at 530 nm ranges from 0.08 to 0.16, and the difference between the refractive indices at 460 nm and at 620 nm ranges from 0.14 to 0.28. This indicates that when compounds P-1 to P-34 are used as light extraction layer materials on the cathode of OLED devices, it is equivalent to introducing a high-refractive-index buffer layer between the cathode and air, increasing the critical angle of total internal reflection, making the escape probabilities of red, green, and blue light nearly equal, and reducing viewing angle-dependent spectral distortion. Therefore, when compounds P-1 to P-34 provided in the embodiments of this application are used as light extraction layer materials, they can maintain sufficiently high light extraction efficiency and effectively improve color shift when achieving multi-angle displays.

[0344] The molecular structures of compound REF01 and compound P-26 are very similar, differing only in the presence of pure carbon-hydrogen fused rings at different fusion sites. Their refractive index curves are shown below. Figure 4 As shown. By Figure 4 It is known that the refractive index of the comparative compound REF01 in the visible light band is generally lower than that of compound P-26 in the visible light band. This is because the delocalized π electrons of the benzene-anthracene group carried by the organic compound of general formula (1) provided in this application have high polarizability and high planarity. The enhanced electron delocalization can improve the polarizability, thereby increasing the refractive index of the organic compound. In addition, compared with the comparative compounds REF02 to REF04, the organic compound of general formula (1) provided in this application has a wider conjugation extension and the electron cloud is more easily distorted, thus resulting in a higher refractive index.

[0345] To facilitate understanding of this application, examples of applications of the organic compounds provided in this application are given below. Those skilled in the art should understand that these examples are merely illustrative and should not be construed as limiting the scope of this application.

[0346] (III) Fabrication and Characterization of OLED Devices

[0347] by Figure 1 Taking the fabrication of the organic light-emitting element (OLED device) shown below as an example, the fabrication method of OLED device using the organic compound of this application will be described in detail below through specific device embodiments.

[0348] In the following method for fabricating OLED devices, ITO conductive glass is used as the anode substrate, HATCN as the hole injection material, HT as the hole transport material, Prime as the light-emitting auxiliary material, BH as the host material of the light-emitting layer, BD as the dopant material of the light-emitting layer, ET and lithium 8-hydroxyquinoline (Liq) as electron transport materials, Liq as the electron injection material, and Ag:Mg as the cathode material. Furthermore, CPL01 is used as the first sub-light extraction layer material, and the series of organic compounds from the aforementioned synthesis examples 1-34 are used as the second sub-light extraction layer materials to fabricate corresponding OLED devices. The chemical structural formulas of HATCN, BH, BD, HT, Prime, ET, and Liq are shown below:

[0349]

[0350] .

[0351] The following specific examples illustrate the fabrication process of OLED devices using the above-mentioned materials.

[0352] Taking the fabrication method of OLED device using compound P-1 as the second photon extraction layer material as an example, the fabricated OLED device is denoted as "OLED-1 device". The fabrication method of OLED-1 device includes the following steps a to j.

[0353] Step a: Cleaning of the ITO conductive glass substrate (first electrode 11). An ITO conductive glass substrate is provided and ultrasonically cleaned using one or more cleaning agents such as deionized water, acetone, isopropanol, or chloroform to improve the work function of the anode.

[0354] Step b: Form a hole injection layer 12 on the first electrode 11. Hole injection material HATCN is deposited on the first electrode 11 at a deposition rate of 1 Å / s to obtain a hole injection layer 12 with a thickness of 30 nm.

[0355] Step c: Form a hole transport layer 13 on the hole injection layer 12. Hole transport material HT is deposited on the hole injection layer 12 at a deposition rate of 1 Å / s to obtain a hole transport layer 13 with a thickness of 60 nm.

[0356] Step d: Form a light-emitting auxiliary layer 14 on the hole transport layer 13. The light-emitting auxiliary material Prime is deposited on the hole transport layer 13 at a deposition rate of 1 Å / s to obtain a light-emitting auxiliary layer 14 with a thickness of 10 nm.

[0357] Step e: Form an organic light-emitting layer 15 on the light-emitting auxiliary layer 14. Using BH as the host material and BD as the dopant material, with a mass ratio of BH to BD of 98:2, BH and BD are deposited on the light-emitting auxiliary layer 14 at a deposition rate of 1 Å / s to obtain an organic light-emitting layer 15 with a thickness of 25 nm.

[0358] Step f: Form an electron transport layer 16 on the organic light-emitting layer 15. In a vacuum chamber, electron transport materials ET and Liq are placed in different evaporation crucibles and subjected to high vacuum (1×10⁻⁶) conditions. -6 Under millibars, ET and Liq are co-deposited at a weight ratio of 5:5 to form an electron transport layer 16 with a thickness of 30 nm on the organic light-emitting layer 15.

[0359] Step g: Form an electron injection layer 17 on the electron transport layer 16. Electron injection material Liq is deposited on the electron transport layer 16 at a deposition rate of 1 Å / s to obtain an electron injection layer 17 with a thickness of 1 nm.

[0360] Step h: Form a second electrode 18 on the electron injection layer 17. Co-deposit cathode material Ag:Mg on the electron injection layer 17 at a evaporation rate of 1 Å / s with a weight ratio of 10:1 to obtain a second electrode 18 with a thickness of 12 nm.

[0361] Step i: Form a light extraction layer 19 on the second electrode 18. The light extraction layer material CPL01 and compound P-1 are sequentially deposited on the second electrode 18 at a deposition rate of 1 Å / s to obtain a first sub-light extraction layer 191 and a second sub-light extraction layer 192 with thicknesses of 20 nm and 60 nm, respectively, which together constitute the light extraction layer 19.

[0362] Step j: The device obtained by layer-by-layer deposition is placed in a nitrogen atmosphere glove box and encapsulated with ultraviolet curing resin to finally obtain the OLED-1 device.

[0363] The structure of the OLED-1 device prepared in this embodiment is: ITO / HATCN (30nm) / HT (60 nm) / Prime (10nm) / BH:BD (2%, 25 nm) / ET:Liq (5:5, 30 nm) / Liq (1nm) / Ag:Mg (10:1, 12nm) / CPL01 (20nm) / compound P-1 (60nm).

[0364] Referring to the fabrication method of OLED-1, compounds P-2 to P-34 synthesized in the examples were selected as materials for the second light extraction layer 192 of the OLED device, and OLED-2 to OLED-34 devices were fabricated accordingly. It can be understood that in the above fabrication methods of OLED-1 to OLED-34 devices, except for the different materials of the second light extraction layer, all other experimental conditions are the same.

[0365] Furthermore, referring to the fabrication method of OLED-1, comparative compounds REF01 to REF04 and CPL01 were used as the first or second sub-light extraction layer materials, respectively, to fabricate OLED-REF01 to OLED-REF06 devices. Compared to the fabrication method of OLED-1, the fabrication methods of OLED-REF01 to OLED-REF06 devices are identical except for the type and combination of light extraction layer materials.

[0366] In this application, the current-voltage (JV) characteristics of OLED-1 to OLED-34 and OLED-REF01 to OLED-REF06 devices were characterized, and the luminous efficiency of the devices was recorded. The results are shown in Table 4. The luminous efficiency is defined as a current density of 10 mA / cm². 2 The relative value obtained at that time.

[0367] Table 4

[0368]

[0369]

[0370] As shown in Table 4, the luminous efficiency of devices OLED-1 to OLED-34, fabricated using the organic compound provided in this application as the second sub-light extraction layer material, is higher than that of devices OLED-REF01 to OLED-REF06. Specifically, compared to devices OLED-REF01 and OLED-REF02 with a single light extraction layer, devices with a double light extraction layer show a significant improvement in luminous efficiency. Furthermore, compared to devices OLED-REF03 to OLED-REF06, devices OLED-1 to OLED-34 have higher luminous efficiency when the first sub-light extraction layer material is CPL01. This is because the organic compound provided in this application, combined with the low-refractive-index light extraction layer material CPL01, achieves an enhanced microcavity effect, further increasing the light extraction efficiency by utilizing the high refractive index advantage. Specifically, in terms of molecular structure, the organic compound provided in this application utilizes a benzene-anthracene group combined with a tertiary amine backbone and heteroatom small fused-ring groups. The resulting conjugated system, with its delocalized π electrons, exhibits high polarizability, and the electron cloud is easily distorted, thus resulting in high refractive index characteristics. Meanwhile, the organic compound provided in this application possesses a certain degree of molecular rigidity and high planarity, which can further amplify the polarization effect while maintaining its own stability. In summary, when the organic compound provided in this application is used as a light extraction layer material, it can effectively utilize its high refractive index advantage to improve the light extraction efficiency of organic light-emitting elements, thereby enhancing device performance, such as improving the luminous efficiency of the device.

[0371] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0372] The above provides a detailed description of an organic compound, composition, organic light-emitting element, and display panel provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An organic compound, characterized in that, The organic compound has the chemical structure shown in general formula (1): (1)； Among them, X1 to X 12 Selected from CH; L 1 Selected from aryl groups with 6 to 14 single bonds or unsubstituted ring atoms; L 2 and L 3 Each is independently selected from at least one of a single bond, an aryl group having 6 to 14 unsubstituted ring atoms, or a heteroaryl group having 6 to 18 unsubstituted ring atoms; n1, n2, and n3 are selected from 1; Ar 1 and Ar 2 Each group is independently selected from any one of the following groups: ； X is selected from O or S; Y is selected from N or CR 4 ; Y1 to Y4 are each independently selected from CH, N, or CR. 5 ; Ar 1 and Ar 2 In this case, ring A is fused at any fused position on the benzene ring, and ring A is selected from an unsubstituted aromatic group with 6 ring atoms. R 2 Selected from phenyl or naphthyl; R 3 Selected from phenyl; R 4 and R 5 Each is independently selected from at least one of H, D, a straight-chain alkyl group having 1 to 20 C atoms, and a straight-chain alkoxy group having 1 to 20 C atoms; " "" indicates a connection point.

2. The organic compound according to claim 1, characterized in that, The organic compound is selected from any one of the compounds shown in general formula (2), general formula (3), general formula (4) and general formula (5): 。 3. The organic compound according to claim 1 or 2, characterized in that, L 1 Selected from single bonds, phenylene, biphenylene, or naphthylene; L 2 and L 3 Each of the following is independently selected from at least one of a single bond, phenylene, biphenylene, naphthylene, dibenzofuranylene, and dibenzothiopheneylene.

4. The organic compound according to claim 1 or 2, characterized in that, Ar 1 and Ar 2 Each group is independently selected from any one of the following groups: 。 5. The organic compound according to claim 1, characterized in that, The organic compound is selected from any one of the following compounds: 。 6. A composition, characterized in that, The composition comprises at least one organic solvent and at least one organic compound as described in any one of claims 1 to 5.

7. An organic light-emitting element, characterized in that, The organic light-emitting element includes: First electrode; The second electrode is disposed opposite to the first electrode; An organic functional layer is located between the first electrode and the second electrode; The light extraction layer is located on the side of the first electrode away from the organic functional layer, or on the side of the second electrode away from the organic functional layer; The material of the light extraction layer includes at least one of the organic compounds according to any one of claims 1 to 5, or the light extraction layer is made using the composition according to claim 6.

8. The organic light-emitting element according to claim 7, characterized in that, The light extraction layer includes a first sub-light extraction layer and a second sub-light extraction layer stacked together, wherein the second sub-light extraction layer is located on the side of the first sub-light extraction layer away from the organic functional layer; The refractive index of the second sub-light extraction layer is greater than that of the first sub-light extraction layer, and the material of the second sub-light extraction layer includes at least one of the organic compounds.

9. The organic light-emitting element according to claim 8, characterized in that, The second sub-light extraction layer has a refractive index greater than 1.99 for light with a wavelength of 630 nm.

10. A display panel, characterized in that, The display panel includes the organic light-emitting element as described in any one of claims 7 to 9.

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