A composition, organic electroluminescent device and display device

Abstract

The application provides a composition, an organic electroluminescent device and a display device. The composition comprises two compounds shown in formula I and one compound shown in formula II; or the composition comprises two compounds shown in formula I and two compounds shown in formula II. In the application, the specific components of the composition are designed, and the composition is used as a light-emitting layer material of an organic electroluminescent device. The prepared organic electroluminescent device has excellent comprehensive performance.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescent materials technology, specifically relating to a composition, an organic electroluminescent device, and a display device. Background Technology

[0002] Organic electroluminescence (EL) refers to the phenomenon where organic materials directly convert electrical energy into light energy under the influence of an electric field. Organic electroluminescent devices are self-emissive light-emitting devices that utilize this principle. They possess characteristics such as self-illumination, vibrant and bright colors, thinness, light weight, fast response speed, wide viewing angle, low driving voltage, tolerance to harsh natural conditions, and the ability to be made into flexible panels. As a result, they have gradually become the most advantageous technology in the next generation of flat panel displays.

[0003] The structure of an organic light-emitting diode (OLED) device includes an anode, a cathode, and an organic layer between them. To improve the efficiency and stability of OLEDs, the organic material layers consist of multiple layers with different materials, such as a hole injection layer (HIL), a hole transport layer (HTL), an electron blocking layer, a light-emitting layer, an electron transport layer (ETL), and an electron injection layer (EIL). The hole injection layer facilitates the injection of holes from the OLED anode into the hole transport layer. The hole injection layer is generally directly adjacent to the anode, and one or more hole transport layers are directly adjacent to the hole injection layer on the cathode side. The hole transport layer is the layer that transports holes. It is generally located between the cathode and the organic layer closest to the anode. The electron blocking layer blocks electrons from the cathode direction. Compared to the hole transport layer, the electron blocking layer has a shallower LUMO (Lower Luminous Moment of Motion), meaning the absolute value of the electron blocking layer's LUMO is smaller than the absolute value of the hole transport layer's LUMO.

[0004] To obtain high-performance organic electroluminescent devices, the research and development of organic materials has attracted widespread attention. Therefore, there is an urgent need in this field to develop more types and higher-performance materials to meet people's higher requirements for OLED devices. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a composition, an organic electroluminescent device, and a display device. In this invention, by designing the specific components of the composition, a composition with excellent performance is obtained. Using this composition as the material for the light-emitting layer of an organic electroluminescent device, a high-performance organic electroluminescent device can be prepared.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a composition comprising a compound of formula I and two compounds of formula II;

[0008] The compound shown in Formula I is obtained by fusion of a group shown in Formula IA with any two adjacent carbon atoms on ring A in the group shown in Formula IB.

[0009]

[0010] Where * represents a fusion site;

[0011] Ar 21 Ar 22 Each is independently selected from C6-C30 aryl or C6-C20 heteroaryl;

[0012] The hydrogen atom in the compound shown in Formula I can be substituted by at least one of -F, -CN, C6-C20 aryl, C1-C6 alkyl, and C1-C6 alkoxy.

[0013] The compound shown in Formula I meets at least one of the following conditions:

[0014] (1) The compound shown in Formula I does not contain deuterium atoms;

[0015] (2) In the compound shown in Formula I, all hydrogen atoms on at least one of the rings A, B, and C are replaced by deuterium atoms;

[0016] (3) Ar in the compound shown in formula I 21 At least one hydrogen atom is replaced by a deuterium atom;

[0017] (4) Ar in the compound shown in Formula I 22 At least one hydrogen atom is replaced by a deuterium atom;

[0018] (5) The hydrogen atoms in the compound shown in Formula I are replaced by C6-C20 aryl groups, and at least one hydrogen atom in the C6-C20 aryl groups is replaced by a deuterium atom.

[0019] (6) In the compound shown in Formula I, the hydrogen atoms are replaced by C1-C6 alkyl and / or C1-C6 alkoxy groups, and all hydrogen atoms in the C1-C6 alkyl and / or C1-C6 alkoxy groups are replaced by deuterium atoms.

[0020] The compound represented by Formula II is as follows:

[0021]

[0022] Among them, Ar 11 Selected from any one of single bonds, phenylene, naphthylene, and biphenylene;

[0023] R 101 R 102 Each is independently selected from H, C6-C30 aryl or C6-C20 heteroaryl;

[0024] X, Y, and Z are each independently selected from N or CR. 301 R 301 It is selected from any one of H, phenyl, biphenyl, naphthyl, 9,9-dimethylfluorenyl, dibenzofuranyl, and dibenzothiopheneyl, and at least one of X, Y, and Z is N;

[0025] X1 is selected from O and S;

[0026] The hydrogen atom in the compound shown in Formula II can be substituted by at least one of -F, -CN, C6-C20 aryl, C1-C6 alkyl, and C1-C6 alkoxy.

[0027] The compound shown in Formula II meets at least one of the following conditions:

[0028] (a) The compound shown in Formula II does not contain deuterium atoms;

[0029] (b) In the compound shown in Formula II, all hydrogen atoms on at least one of the rings F, D, and E are replaced by deuterium atoms;

[0030] (c) R in the compound shown in Formula II 101 At least one hydrogen atom is replaced by a deuterium atom;

[0031] (d) R in the compound shown in formula II 102 At least one hydrogen atom is replaced by a deuterium atom;

[0032] Ar in the compound shown in formula (e) II 11 At least one hydrogen atom is replaced by a deuterium atom;

[0033] (f) R in the compound shown in formula II 301 It is a deuterium atom;

[0034] (g) R in the compound shown in Formula II 301 When selected from phenyl, biphenyl, naphthyl, 9,9-dimethylfluorenyl, dibenzofuranyl, and dibenzothiopheneyl, at least one hydrogen atom in phenyl, biphenyl, naphthyl, 9,9-dimethylfluorenyl, dibenzofuranyl, and dibenzothiopheneyl is replaced by a deuterium atom;

[0035] (h) In the compound shown in Formula II, the hydrogen atoms are replaced by C6-C20 aryl groups, and at least one hydrogen atom in the C6-C20 aryl groups is replaced by a deuterium atom;

[0036] (i) In the compound shown in Formula II, the hydrogen atoms are replaced by C1-C6 alkyl and / or C1-C6 alkoxy atoms, and all the hydrogen atoms in the C1-C6 alkyl and / or C1-C6 alkoxy atoms are replaced by deuterium atoms.

[0037] In this invention, by designing the specific composition of the composition and further using at least two specific compounds in combination, a composition with a specific composition is obtained. Using this composition as the material of the light-emitting layer of an organic electroluminescent device, an organic electroluminescent device with excellent performance can be prepared.

[0038] In this invention, C6 to C30 are selected from C6, C10, C12, C18, C24 or C30, etc.

[0039] The C6 to C20 are selected from C6, C10, C12, C18, or C20, etc.

[0040] C1 to C6 are selected from C1, C2, C3, C4, C5 or C6.

[0041] C1 to C5 are selected from C1, C2, C3, C4 or C5.

[0042] It should be noted that the two compounds represented by Formula I in this invention refer to compounds that both conform to the general formula of Formula I, but the specific structural formulas of the two compounds represented by Formula I are different; similarly, the two compounds represented by Formula II refer to compounds that both conform to the general formula of Formula II, but the specific structural formulas of the two compounds represented by Formula II are different.

[0043] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The purpose and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0044] As a preferred embodiment of the present invention, the composition comprises two compounds of Formula I, and the composition further comprises at least one compound of Formula II.

[0045] Preferably, the composition comprises two compounds of Formula I and one compound of Formula II.

[0046] Preferably, the composition comprises two compounds of Formula I and two compounds of Formula II.

[0047] In this invention, the composition comprises two compounds of Formula I (denoted as compound 1-1 and compound 1-2), and the volume ratio of compound 1-1 to compound 1-2 is (2:8)-(8:2), for example, it can be 2:8, 3:7, 4:6, 5:5, 6:4, 7:3 or 8:2, etc.

[0048] Alternatively, the composition may comprise two compounds of Formula I (denoted as Compound 1-1 and Compound 1-2) and one compound of Formula II (denoted as Compound 2-1), wherein the volume ratio of Compound 1-1, Compound 1-2, and Compound 2-1 is 1:(1-2):(1-6), for example, it may be 1:1:1, 1:1:2, 1:1:3, 1:1:4, 1:2:1, 1:2:2, 1:2:3, 1:2:4, 1:2:5, or 1:2:6, etc.

[0049] Alternatively, the composition may comprise one compound of Formula I (denoted as compound 1-1) and two compounds of Formula II (denoted as compound 2-1 and compound 2-2), wherein the volume ratio of compound 1-1, compound 2-1, and compound 2-2 is (1-6):(1-2):1, for example, it may be 1:1:1, 2:1:1, 3:1:1, 4:1:1, 1:2:1, 2:2:1, 3:2:1, 4:2:1, 5:2:1, or 6:2:1, etc.

[0050] Alternatively, the composition comprises two compounds of Formula I (denoted as compound 1-1 and compound 1-2) and two compounds of Formula II (denoted as compound 2-1 and compound 2-2), wherein the volume ratio of compound 1-1 to compound 1-2 is (2:8) to (8:2), for example, it can be 2:8, 3:7, 4:6, 5:5, 6:4, 7:3 or 8:2, etc., and the volume ratio of compound 2-1 to compound 2-2 is (2:8) to (8:2), for example, it can be 2:8, 3:7, 4:6, 5:5, 6:4, 7:3 or 8:2, etc., and the ratio of the sum of the volumes of compound 1-1 and compound 1-2 to the sum of the volumes of compound 2-1 and compound 2-2 is (2:8) to (8:2), for example, it can be 2:8, 3:7, 4:6, 5:5, 6:4, 7:3 or 8:2, etc.

[0051] Preferably, in the composition, at least one compound of formula I satisfies at least one of conditions (2) to (6).

[0052] Preferably, in the composition, at least one compound of formula I meets at least one of conditions (2) to (6), and the compound of formula II meets condition (a).

[0053] Preferably, the composition comprises a compound of formula I containing deuterium atoms and a compound of formula I that does not contain deuterium atoms.

[0054] The compound containing deuterium atoms shown in Formula I is selected from any one of compounds I-1-D, I-2-D, and I-3-D.

[0055] As a preferred technical solution of the present invention, the Ar21 Ar 22 Each is independently selected from any one or a combination of at least two of phenyl, naphthyl, fluorenyl, anthracene, phenanthryl, diphenyl, dibenzofuranyl, dibenzothiophene, triphenyl or tetraphenyl.

[0056] Preferably, the Ar 21 Selected from phenyl, diphenyl, or triphenyl.

[0057] Preferably, the Ar 22 Selected from diphenyl, triphenyl, or tetraphenyl.

[0058] Preferably, the Ar 21 The Ar is a phenyl group. 22 Selected from diphenyl, triphenyl, or tetraphenyl.

[0059] Preferably, the Ar 21 It is a diphenyl group, and the Ar is... 22 Selected from diphenyl or triphenyl.

[0060] Preferably, the R 101 R 102 Each is independently selected from any one of H, phenyl, naphthyl, triphenylene, fluoranyl, fluorenyl, anthracene, phenanthryl, biphenyl, naphthyl, dibenzofuranyl, and dibenzothiophene.

[0061] Preferably, the R 101 R 102 Each is independently selected from any one of phenyl, biphenyl, or triphenylene.

[0062] Preferably, the R 301 Selected from phenyl.

[0063] Preferably, the Ar 11 It is selected from any one of single bonds, phenylene, or naphthylene.

[0064] As a preferred embodiment of the present invention, the compound represented by Formula I has a structure as shown in Formula I-1, Formula I-2, or Formula I-3:

[0065]

[0066] Among them, Ar 21 Ar 22 It has the same scope of protection as described above;

[0067] Preferably, the compound represented by Formula I meets condition (3) and / or condition (4).

[0068] Preferably, the compound represented by Formula I is selected from any one of compounds I-1-D, I-2-D, and I-3-D:

[0069]

[0070] Among them, Ar 21 Ar 22 It has the same protection scope as the above, and Ar 21 Ar 22 The hydrogen atom was not replaced by a deuterium atom.

[0071] As a preferred embodiment of the present invention, the compound represented by Formula I is selected from any one of the following compounds:

[0072]

[0073]

[0074]

[0075]

[0076] In the above compounds, hydrogen atoms can be replaced by deuterium atoms.

[0077] Preferably, the compound represented by Formula I is selected from any one of compounds H-1 to H-44:

[0078]

[0079]

[0080] The hydrogen atoms in compounds H-1 to H-44 can be replaced by deuterium atoms.

[0081] As a preferred embodiment of the present invention, the compound represented by Formula II is selected from any one of the following compounds:

[0082]

[0083]

[0084]

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

[0091]

[0092]

[0093] In the above compounds, hydrogen atoms can be replaced by deuterium atoms.

[0094] In a second aspect, the present invention provides a compound, said compound comprising the following compounds:

[0095]

[0096] The compound is used to prepare the composition as described in the first aspect.

[0097] Thirdly, the present invention provides an intermediate comprising the following compounds:

[0098]

[0099] The intermediate is used to prepare the compound of formula I in the composition as described in the first aspect.

[0100] It should be noted that in this invention, no special restrictions are placed on the preparation methods of the compounds shown in Formula I and Formula II. They can be prepared by methods commonly used in the art. For example, the preparation methods described in CN112996793A, CN112805277A, and CN102212066A can be referred to.

[0101] Fourthly, the present invention provides an organic electroluminescent device, the organic electroluminescent device comprising an anode, a cathode, and an organic thin film layer disposed between the anode and the cathode;

[0102] The material of the organic thin film layer includes the composition described in the first aspect;

[0103] Preferably, the organic thin film layer includes a light-emitting layer, and the material of the light-emitting layer includes the composition described in the first aspect;

[0104] Preferably, the organic thin film layer includes a hole layer;

[0105] Preferably, the hole layer includes an electron blocking layer; the material of the electron blocking layer includes spirofluorene compounds;

[0106] The spirofluorene compound has the specific structure shown in Formula III below:

[0107]

[0108] Where X is selected from O or S;

[0109] R 11 R 21 Each is independently selected from hydrogen, deuterium, fluorine, CN, substituted or unsubstituted C1-C20 (e.g., C1, C2, C3, C4, C5, C7, C8, C9, C10, C13, C15, C18 or C20, etc.) straight-chain or branched alkyl, substituted or unsubstituted C1-C20 (e.g., C1, C2, C3, C4, C5, C7, C8, C9, C10, C13, C15, C18 or C20, etc.) alkoxy, substituted or unsubstituted C6-C40 (e.g., C6, C8, C10, C12, C15, C18, C24, C30, C36 or C40, etc.) aryl;

[0110] Ar is selected from substituted or unsubstituted C6 to C40 (e.g., C6, C8, C10, C12, C15, C18, C24, C30, C36, or C40, etc.) arylene groups;

[0111] Ar1 and Ar2 are each independently selected from substituted or unsubstituted C6-C40 (e.g., C6, C8, C10, C12, C15, C18, C24, C30, C36, or C40, etc.) aryl, substituted or unsubstituted C12-C40 (C12, C14, C16, C18, C20, C23, C25, C27, C30, C32, C35, C37, C39, or C40, etc.) oxaaryl, substituted or unsubstituted C12-C40 (C12, C14, C16, C18, C20, C23, C25, C27, C30, C32, C35, C37, C39, or C40, etc.) thioaryl, and at least one of Ar1 or Ar2 is selected from any one of phenyl, naphthyl, triphenylene, or fluoranthracene; p is selected from 0 or 1;

[0112] m and n are each independently selected from integers from 0 to 4, for example, they can be 0, 1, 2, 3, 4.

[0113] It should be noted that the oxaaryl group refers to a structure with an oxygen-containing five-membered heterocycle formed by two aromatic rings connected by a single bond and bridged by an O atom. For example, two benzene rings are connected by a single bond to form biphenyl. The carbon atoms on the two benzene rings that make up the biphenyl are simultaneously connected to an O atom to form dibenzofuran.

[0114] The thioheroaryl group refers to a structure with a sulfur-containing five-membered heterocycle formed by two aromatic rings connected by a single bond and bridged by an S atom. For example, two benzene rings are connected by a single bond to form biphenyl. The carbon atoms on the two benzene rings that make up the biphenyl are simultaneously connected to an S atom to form dibenzothiophene.

[0115] Preferably, the spirofluorene compound is selected from the compounds shown in III-1 or III-2:

[0116]

[0117] Among them, X and X1 are each independently selected from O or S;

[0118] R 11 R 21 Ar has the same protection scope as the above;

[0119] Ar1 is selected from any one of phenyl, naphthyl, triphenylene, or fluoranthyl;

[0120] R 31 Selected from C1 to C20 (e.g., C1, C2, C3, C4, C5, C7, C8, C9, C10, C13, C15, C18, or C20, etc.) straight-chain or branched alkyl groups, C1 to C20 (e.g., C1, C2, C3, C4, C5, C7, C8, C9, C10, C13, C15, C18, or C20, etc.) alkoxy groups, and C6 to C40 (e.g., C6, C8, C10, C12, C15, C18, C24, C30, C36, or C40, etc.) aryl groups;

[0121] R 41 R 42 Each is independently selected from C1 to C20 (e.g., C1, C2, C3, C4, C5, C7, C8, C9, C10, C13, C15, C18, or C20, etc.) straight-chain or branched alkyl groups, and C6 to C40 (e.g., C6, C8, C10, C12, C15, C18, C24, C30, C36, or C40, etc.) aryl groups, and R 41 and R 42 They can be independent of each other or connected in a ring by a single bond.

[0122] Preferably, the spirofluorene compound is selected from any one of the following compounds 1-140 and compounds 1S-140S:

[0123]

[0124]

[0125]

[0126]

[0127]

[0128]

[0129]

[0130]

[0131]

[0132] The compound 1S-140S is a mixture of compound 1-140... Replace with The dashed lines represent connection points.

[0133] For example, the structure of compound 2 is The structure of compound 2S is then:

[0134] Fifthly, the present invention provides a display device comprising the organic electroluminescent device as described in the fourth aspect.

[0135] Compared with the prior art, the present invention has the following beneficial effects:

[0136] By designing the specific components of the composition and further using at least two specific compounds in combination, a composition with a specific composition is obtained. Using this composition as the material of the light-emitting layer of an organic electroluminescent device, an organic electroluminescent device with low driving voltage, high current efficiency, and long lifespan can be prepared. Detailed Implementation

[0137] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0138] Preparation Example 1

[0139] This synthetic example provides compound H-28-D1 and its synthetic method, which is as follows:

[0140]

[0141] Under nitrogen protection, 400 mL of dry tetrahydrofuran and 0.1 mol of E-4-1 were added to a 2000 mL three-necked flask. The temperature was lowered to -75 to -80 °C under nitrogen protection, and 0.12 mol of n-BuLi was slowly added dropwise. After the addition was complete, the reaction was maintained at -75 to -80 °C for 1 h. Then, 0.15 mol of trimethyl borate was added dropwise. After the addition was complete, the reaction was maintained at -75 to -80 °C for 0.5 h. The temperature was slowly raised to 0 °C, and 10% dilute hydrochloric acid was added dropwise until the pH of the system was ≈4. The mixture was separated, and the aqueous phase was extracted twice with 400 mL of ethyl acetate. The organic phases were combined, washed three times with water, and concentrated to dryness. The obtained solid was slurried with n-heptane to obtain compound E-4-2.

[0142] Preparation Example 2

[0143]

[0144] Referring to Preparation Example 1, E-4D-1 was replaced with E-4D-1 in Preparation Example 1, and all other operations remained unchanged, to obtain E-4D-2.

[0145] Preparation Example 3

[0146]

[0147] Under nitrogen protection, 80 mL of dry toluene, 0.01 mol of compound E-13-0, 0.01 mol of 2-bromo-6-iodonaphthalene, 0.0005 mol of Pd(dba)2 (bis(dibenzylacetone)palladium), 0.4 g of a 10% (w / w) toluene solution of tri-tert-butylphosphine, and 1.44 g of sodium tert-butoxide were added to a 250 mL three-necked flask. The mixture was slowly heated to reflux and reacted for 8 hours. After cooling to room temperature, water was added to dissolve the mixture. The organic layer was then washed with water until neutral, dried with magnesium sulfate, filtered to remove magnesium sulfate, concentrated to dryness, and separated by silica gel column chromatography with petroleum ether:dichloromethane = 10:1 (v / v) to obtain intermediate E-13-1.

[0148] Referring to Preparation Example 1, by replacing E-4-1 with E-13-1 while keeping other operations unchanged, intermediate E-13-2 can be obtained.

[0149] Preparation Examples 4-7

[0150] Preparation Examples 4-7 provide a compound and its synthesis method, respectively. An intermediate is synthesized by reactant 1 and reactant 2, and then the intermediate is reacted with the corresponding bromide to obtain the corresponding compound (see Table 1 below). The specific synthesis method is the same as that in Preparation Example 3.

[0151]

[0152]

[0153] Synthesis Example 1

[0154]

[0155] 0.1 mol of E-5-2 and 0.1 mol of chlorinated compound 1 were added to a 1000 mL three-necked flask, followed by 400 mL of toluene, 40 mL of water, 0.005 mol of Pd(dba)2 (bis(dibenzylacetone)palladium), 0.005 mol of x-phos (2-dicyclohexylphospho-2',4',6'-triisopropylbiphenyl), and 0.15 mol of potassium carbonate. After nitrogen purging, the mixture was heated to 110 °C and reacted for 16 h. After cooling to room temperature, the mixture was separated, dried, and subjected to column chromatography. The resulting product was then recrystallized from toluene to obtain compound E-5. The intermediate E-5 was analyzed by mass spectrometry, and the mass-to-charge ratio (m / z) was found to be 640.23.

[0156] Synthesis Examples 2-6

[0157] Synthesis Examples 2-6 provide a compound and its synthesis method, respectively. The corresponding compound is synthesized by reactant 1 and reactant 2 (see Table 2 below). The specific synthesis method is the same as that in Synthesis Example 1.

[0158] Table 2

[0159]

[0160]

[0161] Other compounds for which specific synthesis steps are not listed can be prepared using common knowledge in the art, in conjunction with the above examples.

[0162] The specific structures of the compounds used in the device embodiments and device comparative examples are as follows:

[0163]

[0164]

[0165]

[0166]

[0167]

[0168] Device Example 1

[0169] This embodiment of the device provides an organic electroluminescent device, in which the composition provided by the present invention is selected as the red light host material in the organic electroluminescent device.

[0170] The structure of the organic electroluminescent device is as follows: ITO / HT-1 (20nm) / red light host material (35nm): Ir(piq)3 [10%] / TPBI (10nm) / Alq3 (15nm) / LiF (0.5nm) / Al (150nm). Here, "Ir(piq)3 [10%]" refers to the doping ratio of the red light dye, i.e., the volume ratio of the red light host material to Ir(piq)3 is 90:10.

[0171] The fabrication process of organic electroluminescent devices is as follows:

[0172] The glass plate coated with the ITO transparent conductive layer was ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in a acetone:ethanol mixed solvent, baked in a clean environment until all moisture was removed, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam.

[0173] The glass substrate with the anode was placed in a vacuum chamber and evacuated to a vacuum level of 1×10⁻⁶. -5 ~9×10 -4 Pa, a hole transport layer HT-1 is vacuum-deposited on the above-mentioned anodic layer film at a deposition rate of 0.1 nm / s and a film thickness of 20 nm.

[0174] A red light host material and dye Ir(piq)3 are vacuum-deposited on a hole transport layer to serve as the light-emitting layer of an organic electroluminescent device. The deposition rate is 0.1 nm / s, and the total film thickness is 35 nm. In this embodiment, if the red light host is compound H-3, compound H-3-DE, compound E-1, or compound E-1D, compound H-3, compound H-3-DE, compound E-1, and compound E-1D are placed in different evaporation sources and heated. The heating rate is controlled so that the volume ratio of each material deposited on the substrate is 1:1:1:1, which serves as the red light host material.

[0175] Electron transport layers TPBI and Alq3 were sequentially vacuum-deposited on top of the light-emitting layer at a deposition rate of 0.1 nm / s, with film thicknesses of 10 nm and 15 nm, respectively.

[0176] 0.5 nm of LiF was vacuum-deposited on the electron transport layer, and 150 nm of Al was used as the electron injection layer and cathode.

[0177] Device Examples 2-13, 2-1, and 2-2

[0178] Comparative Examples 2-13, 2-1, and 2-2 each provide an organic electroluminescent device. The only difference between them and Example 1 is that the red light host material is different. If the red light host is two or more compounds, each compound is placed in a different evaporation source for heating. The heating rate is controlled so that the volume ratio of each compound deposited on the substrate is the same, which serves as the red light host material (see Table 3 below). Other preparation steps and conditions are the same as those in Example 1.

[0179] Device Comparison Examples 1-4

[0180] Comparative Examples 1-4 each provide an organic electroluminescent device. The only difference between them and Example 1 is that the main material for red light is different (see Table 3 below). The other preparation steps and conditions are the same as those in Example 1.

[0181] Performance testing:

[0182] The brightness, driving voltage, current efficiency, and lifetime (LT90) of the fabricated organic electroluminescent device were measured using an OLED-1000 multi-channel accelerated aging lifetime and photochromic performance analysis system manufactured by Hangzhou Yuanfang. The lifetime test (LT90) refers to maintaining a constant current density (1000 cd / m²) at room temperature (25–27°C) while retaining the initial brightness. 2 The time required for the brightness to decrease to 90% of its initial brightness. In the table below, the driving voltage, current efficiency, and LT90 lifetime are all relative values. See Table 3 below for detailed test results.

[0183] Table 3

[0184]

[0185] The " / " indicates that this component does not exist.

[0186] A comparison of Device Example 1 and Device Comparative Examples 1-2 shows that the performance of the organic electroluminescent device prepared by using a composition containing four compounds in this invention is better than that of the organic electroluminescent device prepared by using a combination of two compounds.

[0187] As can be seen from the comparison between Device Example 12 and Device Comparative Examples 3-4, the organic electroluminescent device prepared by using two compounds shown in Formula II of the present invention has better overall performance.

[0188] Comparing the specific embodiments and comparative examples above, it can be seen that device embodiment 11 has the lowest driving voltage; device embodiments 12-13 have better lifespans; and device embodiment 12 has the highest current efficiency.

[0189] Comparing Device Example 2-1 and Device Example 2-2, it can be seen that when the compound shown in Formula I is selected from any one of compounds I-1-D, I-2-D, and I-3-D, the device has a better lifespan.

[0190] As can be seen from the above embodiments, by designing the specific components of the compound of formula II provided by the present invention, and further by using at least two specific compounds in combination, a composition with a specific composition is obtained. Using this composition as the material of the light-emitting layer of an organic electroluminescent device, an organic electroluminescent device with low driving voltage, high current efficiency and long life can be prepared.

[0191] Device Example 14

[0192] This embodiment of the device provides an organic electroluminescent device, in which the composition provided by the present invention is selected as the red light host material in the organic electroluminescent device.

[0193] The structure of the organic electroluminescent device is as follows: ITO / HT-1 (20nm) / electron blocking layer (5nm) / red light host material (35nm): Ir(piq)3 [10%] / TPBI (10nm) / Alq3 (15nm) / LiF (0.5nm) / Al (150nm). Here, "Ir(piq)3 [10%]" refers to the doping ratio of the red light dye, i.e., the volume ratio of the red light host material to Ir(piq)3 is 90:10.

[0194] The fabrication process of organic electroluminescent devices is as follows:

[0195] The glass plate coated with the ITO transparent conductive layer was ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in a acetone:ethanol mixed solvent, baked in a clean environment until all moisture was removed, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam.

[0196] The glass substrate with the anode was placed in a vacuum chamber and evacuated to a vacuum level of 1×10⁻⁶. -5 ~9×10 -4 Pa, a hole transport layer HT-1 is vacuum-deposited on the above-mentioned anodic layer film at a deposition rate of 0.1 nm / s and a film thickness of 20 nm.

[0197] EB was vacuum-deposited on top of the hole transport layer as an electron blocking layer at a deposition rate of 0.1 nm / s and a film thickness of 5 nm.

[0198] A red light host material and dye Ir(piq)3 were vacuum-deposited on an electron blocking layer to serve as the light-emitting layer of an organic electroluminescent device. The deposition rate was 0.1 nm / s, and the total film thickness was 35 nm. In this embodiment, the red light host materials were H-3, H-3-DE, E-15, and E-15D. Each compound was placed in a different evaporation source and heated. The heating rate was controlled to ensure that the volume ratio of each material deposited on the substrate was the same, thus serving as the red light host material.

[0199] Electron transport layers TPBI and Alq3 were sequentially vacuum-deposited on top of the light-emitting layer at a deposition rate of 0.1 nm / s, with film thicknesses of 10 nm and 15 nm, respectively.

[0200] 0.5 nm of LiF was vacuum-deposited on the electron transport layer, and 150 nm of Al was used as the electron injection layer and cathode.

[0201] Device Examples 15-16

[0202] Device Examples 15-16 provide an organic electroluminescent device, which differs from Device Example 14 only in that the electron blocking layer material is different (see Table 4 below). The other preparation steps and conditions are the same as those in Device Example 14.

[0203] The performance of the organic electroluminescent devices provided in Device Examples 14-16 was tested using the same methods as above. The test results are detailed in Table 4 below.

[0204] Table 4

[0205]

[0206] As shown in Table 4, by selecting spirofluorene compounds with specific structures as the electron blocking layer material and combining them with the composition provided in this invention as the light-emitting layer material, the organic electroluminescent devices prepared in this invention exhibit higher current efficiency and longer lifespan. Furthermore, the device performance is even better when EB-C is used as the electron blocking layer.

[0207] The applicant declares that the detailed process flow of this invention is illustrated by the above embodiments, but this invention is not limited to the above detailed process flow, that is, it does not mean that this invention must rely on the above detailed process flow to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the product of this invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. A composition, characterized in that, The composition comprises a formula The compound shown and two formulas The compound shown; The formula The compound shown is selected from any one of the following compounds: ； In the above compounds, hydrogen atoms can be replaced by deuterium atoms; The compound represented by Formula II is selected from any one of the following compounds: In the above compounds, hydrogen atoms can be replaced by deuterium atoms.

2. The composition according to claim 1, characterized in that, The composition comprises two formulas. The compound shown, the composition further includes at least one of the following formulas: The compound shown.

3. The composition according to claim 1, characterized in that, The composition comprises two formulas. The compound shown and a formula The compound shown.

4. The composition according to claim 1, characterized in that, The composition comprises two formulas. The compound shown and two formulas The compound shown.

5. The composition according to any one of claims 2 to 4, characterized in that, The composition includes a compound containing deuterium atoms. The compound shown is a compound of formula I that does not contain deuterium atoms.

6. The composition according to claim 1, characterized in that, The formula The compound shown is selected from any one of compounds H-1 to H-44: ； The hydrogen atoms in compounds H-1 to H-44 can be replaced by deuterium atoms.

7. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes an anode, a cathode, and an organic thin film layer disposed between the anode and the cathode; The material of the organic thin film layer includes the composition as described in any one of claims 1-6.

8. The organic electroluminescent device according to claim 7, characterized in that, The organic thin film layer includes a light-emitting layer, and the material of the light-emitting layer includes the composition according to any one of claims 1-6.

9. The organic electroluminescent device according to claim 7, characterized in that, The organic thin film layer includes a void layer.

10. The organic electroluminescent device according to claim 9, characterized in that, The hole layer includes an electron blocking layer; the material of the electron blocking layer includes spirofluorene compounds; The spirofluorene compounds have the following formula: The structure shown is as follows: Mode ; Where X is selected from O or S; R 11 R 21 Each is independently selected from hydrogen, deuterium, fluorine, CN, unsubstituted C1~C20 straight-chain or branched alkyl, unsubstituted C1~C20 alkoxy, and unsubstituted C6~C40 aryl; Ar is selected from unsubstituted C6~C40 arylene groups; Ar1 and Ar2 are each independently selected from unsubstituted C6~C40 aryl, unsubstituted C12~C40 oxaaryl, and unsubstituted C12~C40 thiaaryl, and at least one of Ar1 or Ar2 is selected from any one of phenyl, naphthyl, triphenylene or fluoranthyl. p is selected from 0; m and n are each independently selected from 0 or 1.

11. A display device, characterized in that, The display device includes the organic electroluminescent device as described in claim 7.

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