A composition, intermediate and organic electroluminescent device containing an indolocarbazole compound

Abstract

The application provides a composition containing an indolocarbazole compound, an intermediate and an organic electroluminescent device. The composition contains at least one first compound and at least one second compound; the first compound is obtained by fusing a group shown in formula I-A with any two adjacent carbon atoms on ring A in a group shown in formula I; and the second compound is selected from any one of compounds shown in formulae II-1, II-2 and II-3. The composition provided by the application can be used as a light-emitting layer host material to prepare an organic electroluminescent device, and the prepared organic electroluminescent device has a lower driving voltage, a higher current efficiency and a longer service life.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescent materials technology, specifically relating to a composition, intermediate, and organic electroluminescent device containing indole-carbazole compounds. Background Technology

[0002] Currently, organic light-emitting diode (OLED) display technology has been applied in smartphones, tablets, and other fields, and will further expand to large-size applications such as televisions. Over the past 30 years of development, various high-performance OLED materials have been developed. Through different designs of device structures and optimization of device lifespan, efficiency, and other performance characteristics, the commercialization of OLEDs has been accelerated, leading to their widespread application in display and lighting fields.

[0003] The selection of hole layer, light-emitting layer and other organic functional layer materials also has a significant impact on the current efficiency, driving voltage and lifetime of the device. Currently, we are still exploring functional layer materials with higher performance.

[0004] Therefore, in order to meet people's higher requirements for OLED devices, there is an urgent need in this field to develop more types and higher performance OLED materials. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a composition, intermediate, and organic electroluminescent device containing an indole-carbazole compound. In this invention, by using an indole-carbazole compound (first compound) and a second compound in combination, a composition is obtained. Using this composition as the main material of the light-emitting layer, the resulting organic electroluminescent device exhibits excellent performance.

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

[0007] In a first aspect, the present invention provides a composition containing an indolecarbazole compound, the composition comprising at least one first compound and at least one second compound;

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

[0009]

[0010] Among them, Ar 21 Ar 22 Each is independently selected from any one of phenyl, biphenyl, triphenyl, or tetraphenyl, and * indicates a fusion site;

[0011] The second compound is selected from any one of the compounds shown in formula II-1, II-2, and II-3:

[0012]

[0013] Among them, Ar 11 Ar 12 Ar 33 Each is independently selected from phenyl or biphenyl;

[0014] Ar 13 Selected from phenylene or biphenylene;

[0015] In both the first and second compounds, hydrogen atoms can be independently replaced by deuterium atoms.

[0016] In this invention, an indole-carbazole compound (first compound) and a second compound are used in combination to obtain a composition. This composition is then used as the main material for the light-emitting layer. The resulting organic electroluminescent device exhibits a low driving voltage, high current efficiency, and long lifespan.

[0017] 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.

[0018] As a preferred embodiment of the present invention, the first compound is selected from any one of the compounds shown in formulas I-1, I-2, and I-3:

[0019]

[0020] Among them, Ar 21 Ar 22 It has the same scope of protection as the first aspect;

[0021] In the compounds shown in formulas I-1, I-2, and I-3, each hydrogen atom can be independently replaced by a deuterium atom.

[0022] Preferably, the first compound is selected from any one of the compounds shown in formula I-1-D, I-2-D, and I-3-D:

[0023]

[0024] Among them, Ar 21 Ar 22 It has the same protection scope as the first aspect, and Ar 21 Ar 22 It does not contain deuterium atoms.

[0025] As a preferred technical solution of the present invention, the Ar 21 Ar 22 The sum of the number of benzene rings is selected from an integer greater than or equal to 4.

[0026] Preferably, the Ar 21 The Ar is a phenyl group. 22 It is selected from any one of biphenyl, terphenyl, or tetraphenyl.

[0027] Preferably, the Ar 21 It is a biphenyl, and the Ar is... 22 Selected from biphenyl or terphenyl.

[0028] As a preferred embodiment of the present invention, the first compound is selected from any one of the following substituted or unsubstituted compounds:

[0029]

[0030] The substitution refers to the fact that each hydrogen atom in the above compound can be independently replaced by a deuterium atom.

[0031] Preferably, the first compound is selected from any one of the following substituted or unsubstituted compounds H-1 to H-20:

[0032]

[0033] Wherein, the substitution refers to the independent substitution of each hydrogen atom in compounds H-1 to H-12 by a deuterium atom. Preferably, the first compound is selected from any one of the following compounds:

[0034]

[0035] As a preferred technical solution of the present invention, the Ar 33 Selected from phenyl.

[0036] Preferably, the Ar 13 Selected from phenylene.

[0037] As a preferred embodiment of the present invention, the second compound is selected from any one of the following substituted or unsubstituted compounds:

[0038]

[0039]

[0040] The substitution refers to the fact that each hydrogen atom in the above compound can be independently replaced by a deuterium atom.

[0041] Preferably, the second compound is selected from any one of the following substituted or unsubstituted compounds E-1 to E-10:

[0042]

[0043] The substitution refers to the independent replacement of hydrogen atoms in compounds E-1 to E-10 by deuterium atoms.

[0044] Preferably, the second compound is selected from any one of the following compounds:

[0045]

[0046] As a preferred embodiment of the present invention, in the composition, at least one hydrogen atom in the first compound is replaced by a deuterium atom.

[0047] Preferably, in the composition, at least one hydrogen atom in the first compound is replaced by a deuterium atom, and in the second compound, the hydrogen atom is not replaced by a deuterium atom.

[0048] In a second aspect, the present invention provides a compound selected from the following compounds:

[0049]

[0050]

[0051] The compound is used to prepare the composition as described in the first aspect.

[0052] Thirdly, the present invention provides an intermediate selected from any one of the following compounds:

[0053]

[0054]

[0055] The intermediate is used to prepare the first compound in the composition as described in the first aspect.

[0056] It should be noted that the preparation methods of the first and second compounds in this invention are not specifically limited, and are exemplary but include, but are not limited to: the first compound can be obtained by reacting the above intermediate with the corresponding brominated product.

[0057] 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;

[0058] The material of the organic thin film layer includes the composition described in the first aspect.

[0059] Preferably, the organic thin film layer includes a hole layer and a light-emitting layer.

[0060] The main material of the light-emitting layer includes the composition described in the first aspect.

[0061] As a preferred embodiment of the present invention, the hole layer includes an electron blocking layer, and the material of the electron blocking layer includes spirofluorene compounds;

[0062] The spirofluorene compound has the specific structure shown in Formula III below:

[0063]

[0064] Where X is selected from O or S;

[0065] 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;

[0066] 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;

[0067] 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 fluoranthyl.

[0068] p is selected from 0 or 1;

[0069] m and n are each independently selected from integers from 0 to 4, for example, they can be 0, 1, 2, 3, 4.

[0070] 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.

[0071] 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.

[0072] Preferably, the spirofluorene compound is selected from the compounds shown in III-1 or III-2:

[0073]

[0074] Among them, X and X1 are each independently selected from O or S;

[0075] R 11 R 21 Ar has the same protection scope as the above;

[0076] Ar1 is selected from any one of phenyl, naphthyl, triphenylene, or fluoranthyl;

[0077] 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;

[0078] 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.

[0079] Preferably, the spirofluorene compound is selected from any one of the following compounds 1-140 and compounds 1S-140S:

[0080]

[0081]

[0082]

[0083]

[0084]

[0085]

[0086]

[0087]

[0088] The compound 1S-140S is a mixture of compound 1-140... Replace with The dashed lines represent connection points.

[0089] For example, the structure of compound 2 is The structure of compound 2S is then:

[0090] Compared with the prior art, the present invention has the following beneficial effects:

[0091] In this invention, an indole-carbazole compound (first compound) and a second compound are used in combination to obtain a composition. This composition is then used as the main material for the light-emitting layer. The resulting organic electroluminescent device exhibits a low driving voltage, high current efficiency, and long lifespan. Detailed Implementation

[0092] 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.

[0093] Preparation Example 1

[0094] This preparation example provides an intermediate IBC-1-D and its synthesis method, the synthesis method being as follows:

[0095]

[0096] At 25°C, the compound IBC-1 (5.0 g), palladium chloride (0.030 g), anhydrous nickel chloride (0.021 g), activated carbon (0.3 g), D2O (35 mL), and C6D6 (120 mL) were added to a 500 mL autoclave, and hydrogen gas was introduced into the autoclave until the pressure reached 0.02 MPa. The autoclave was then heated to 90°C and reacted for 40 hours. After cooling to room temperature, the mixture was filtered and separated. The organic layer after separation was dried with magnesium sulfate, decolorized using a short silica gel column, concentrated to dryness, and crystallized twice with toluene to obtain intermediate IBC-1-D (4.9 g).

[0097] The intermediate IBC-1-D was analyzed by mass spectrometry, and the mass-to-charge ratio (m / z) was found to be 268.18.

[0098] Preparation Example 2

[0099] This preparation example provides an intermediate IBC-2-D and its synthesis method, the synthesis method being as follows:

[0100]

[0101] The synthesis method is the same as that of intermediate IBC-1-D, except that the compound shown in IBC-1 is replaced with an equal amount of the compound shown in IBC-2, while all other conditions are the same.

[0102] The intermediate IBC-1-D was analyzed by mass spectrometry, and the mass-to-charge ratio (m / z) was found to be 268.18.

[0103] Preparation Example 3

[0104] This preparation example provides an intermediate IBC-3-D and its synthesis method, the synthesis method being as follows:

[0105]

[0106] The synthesis method is the same as that of intermediate IBC-1-D, except that the compound shown in IBC-1 is replaced with an equal amount of the compound shown in IBC-3, while all other conditions are the same.

[0107] The intermediate IBC-3-D was analyzed by mass spectrometry, and the mass-to-charge ratio (m / z) was found to be 268.18.

[0108] Preparation Example 4

[0109] This preparation example provides an intermediate IBC-1-DH and its synthesis method, the synthesis method being as follows:

[0110]

[0111] Add 2.68 g of the compound IBC-1-D and 50 mL of dry tetrahydrofuran to a 250 mL three-necked flask. Cool to -50 °C and slowly add 14 mL of a 1.6 M butyllithium solution in n-hexane. After the addition is complete, keep the temperature at -50 °C for 30 minutes. Slowly add 2 g of methanol and heat to room temperature. Add water and dichloromethane to separate the layers. Wash the organic layer with water, dry it with magnesium sulfate, and then separate it by silica gel column chromatography to obtain intermediate IBC-1-DH (2.3 g).

[0112] The intermediate IBC-1-DH was analyzed by mass spectrometry, and the mass-to-charge ratio (m / z) was found to be 266.16.

[0113] Preparation Example 5

[0114] This preparation example provides an intermediate IBC-2-DH and its synthesis method, the synthesis method being as follows:

[0115]

[0116] The synthesis method is the same as that for intermediate IBC-1-DH, except that the compound shown in IBC-1-D is replaced with an equal amount of the compound shown in IBC-2-D, while all other conditions are the same.

[0117] The intermediate IBC-1-DH was analyzed by mass spectrometry, and the mass-to-charge ratio (m / z) was found to be 266.16.

[0118] Preparation Example 6

[0119] This preparation example provides an intermediate IBC-3-DH and its synthesis method, the synthesis method being as follows:

[0120]

[0121] The synthesis method is the same as that for intermediate IBC-1-DH, except that the compound shown in IBC-1-D is replaced with an equal amount of the compound shown in IBC-3-D, while all other conditions are the same.

[0122] The intermediate IBC-1-DH was analyzed by mass spectrometry, and the mass-to-charge ratio (m / z) was found to be 266.16.

[0123] Synthesis Example 1

[0124] This synthetic example provides a compound H-6 and its synthetic method, the synthetic method being as follows:

[0125]

[0126] (1) Synthesis of intermediate H-6-1

[0127] Under nitrogen protection, 80 mL of dry toluene, intermediate IBC-1 (2.56 g), bromobenzene (1.57 g), Pd(dba)2 (bis(dibenzylacetone palladium, 0.0575 g), a 10% (w / w) toluene solution of tri-tert-butylphosphine (0.4 g), and sodium tert-butoxide (1.44 g) 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. The elution was performed with petroleum ether:dichloromethane = 10:1 (v / v) to obtain intermediate H-6-1 (2.9 g).

[0128] Mass spectrometry analysis of intermediate H-6-1 revealed a mass-to-charge ratio (m / z) of 332.13.

[0129] NMR analysis was performed on intermediate H-6-1, and the results were obtained. 1 H-NMR (Bruker, Switzerland, Avance II 400MHz nuclear magnetic resonance spectrometer, CDCl3): δ8.39 (m, 1H), δ8.21 (m, 1H), δ7.66 (s, 1H), δ7.62~7.39 (m, 8H), δ7.21~7.09 (m, 5H).

[0130] (2) Synthesis of compound H-6

[0131] The synthesis method of intermediate H-6-1 is the same, except that intermediate IBC-1 is replaced with an equal amount of intermediate H-6-1 and bromobenzene is replaced with an equal amount of bromotetraphenyl to obtain compound H-6.

[0132] Mass spectrometry analysis of H-6 revealed a mass-to-charge ratio (m / z) of 636.26.

[0133] Synthesis Example 2

[0134] This synthetic example provides a compound H-2-D and its synthetic method, the synthetic method being as follows:

[0135]

[0136] (1) Synthesis of intermediate H-2-D-1

[0137] The synthesis of intermediate H-6-1 was carried out in the same manner as in Example 1, except that bromobenzene was replaced with an equal amount of deuterated bromobenzene to obtain intermediate H-2-D-1.

[0138] Mass spectrometry analysis of intermediate H-2-D-1 revealed a mass-to-charge ratio (m / z) of 337.16.

[0139] (2) Synthesis of compound H-2-D

[0140] The synthesis of compound H-6 was performed in the same manner as in Example 1, except that intermediate H-6-1 was replaced with an equimolar amount of intermediate H-2-D-1, and bromotetraphenyl was replaced with an equimolar amount of... The compound H-2-D was obtained.

[0141] Mass spectrometry analysis of compound H-2-D showed a mass-to-charge ratio (m / z) of 565.26.

[0142] Synthesis Example 3

[0143] This synthetic example provides a compound H-6-DE and its synthetic method, the synthetic method being as follows:

[0144]

[0145] (1) Synthesis of intermediate H-6-DE-1

[0146] The synthesis of intermediate H-6-1 is described in the same way as in Example 1, except that intermediate IBC-1 is replaced with IBC-1-D to obtain intermediate H-6-DE-1.

[0147] Mass spectrometry analysis of intermediate H-6-DE-1 revealed a mass-to-charge ratio (m / z) of 343.20.

[0148] (2) Synthesis of compound H-6-DE

[0149] The synthesis of compound H-6 was carried out in the same manner as in Example 1, except that intermediate H-6-1 was replaced with intermediate H-6-DE-1 to obtain compound H-6-DE.

[0150] Mass spectrometry analysis of compound H-6-DE showed a mass-to-charge ratio (m / z) of 646.32.

[0151] In addition, this synthetic example provides another synthetic method for compound H-6-DE, as follows:

[0152]

[0153] (1′) Synthesis of intermediate H-6-DE-1

[0154] The synthesis method in step (1) is the same, except that the intermediate IBC-1-D is replaced with an equal amount of IBC-1-DH to obtain the intermediate H-6-DE-1H.

[0155] Mass spectrometry analysis of intermediate H-6-DE-1H revealed a mass-to-charge ratio (m / z) of 342.19.

[0156] (2′) Synthesis of compound H-6-DE

[0157] The synthesis method in step (2) is the same, except that intermediate H-6-DE-1 is replaced with an equal amount of intermediate H-6-DE-1H to obtain compound H-6-DE.

[0158] Mass spectrometry analysis of compound H-6-DE showed a mass-to-charge ratio (m / z) of 646.32.

[0159] Synthesis Examples 4-8

[0160] Synthesis Examples 4-8 provide a first compound and its synthesis method, respectively. An intermediate is synthesized from reactant 1 and reactant 2, and then the intermediate reacts with the corresponding brominated product to obtain the corresponding compound. The synthesis method is the same as that provided in Synthesis Example 1. The specific structures of the reactants, intermediates and first compound are detailed in Table 1.

[0161] Mass spectrometry was used to detect the synthesized intermediates and compounds. The mass-to-charge ratio (m / z) is detailed in Table 1.

[0162] Table 1

[0163]

[0164]

[0165] Synthesis Example 9

[0166] This synthetic example provides a compound E-2 and its synthetic method, as follows:

[0167]

[0168] Under nitrogen protection, 200 mL of toluene, 30 mL of ethanol, and 20 mL of water were added sequentially to a 500 mL three-necked flask. Then, compound E-2-1 (3.44 g), compound E-2-2 (4.52 g), sodium carbonate (2.12 g, 0.02 mol), and tetraphenylphosphine palladium (0.23 g, 0.0002 mol) were added. The mixture was slowly heated to reflux and reacted for 8 h. After cooling to room temperature, water and toluene were added to separate the layers. The organic layer was washed with water until neutral, dried over magnesium sulfate, filtered to remove the desiccant, concentrated to dryness, and separated by silica gel column chromatography. The eluent was petroleum ether: ethyl acetate: dichloromethane = 20:4:1 (volume ratio) to give compound E-2 (5.81 g).

[0169] Mass spectrometry analysis of compound E-2 revealed a mass-to-charge ratio (m / z) of 715.27.

[0170] Synthesis Example 10

[0171] This synthetic example provides a compound E-3 and its synthetic method, as follows:

[0172]

[0173] The synthesis method of compound E-2 is the same, except that the compound shown in E-2-1 is replaced with an equal amount of the compound shown in E-3-1 to obtain compound E-3.

[0174] Mass spectrometry analysis of compound E-3 showed a mass-to-charge ratio (m / z) of 791.30.

[0175] Synthesis Example 11

[0176] This synthetic example provides a compound E-6 and its synthetic method, as follows:

[0177]

[0178] The synthesis method of compound H-6 is the same, except that H-6-1 is replaced with an equal amount of E-6-1 and bromotetraphenyl is replaced with an equal amount of E-6-2 to obtain compound E-6.

[0179] Mass spectrometry analysis of compound E-6 revealed a mass-to-charge ratio (m / z) of 715.27.

[0180] Synthesis Examples 12-15

[0181] Examples 12-15 of this synthesis provide a second compound and its synthesis method, which is obtained by reacting a carbazole compound with the corresponding bromide. The synthesis method is the same as that of compound E-6. The specific reactants and the structure of the second compound are detailed in Table 2.

[0182] The synthesized intermediates and compounds were analyzed by mass spectrometry, and the mass-to-charge ratios (m / z) are detailed in Table 2.

[0183] Table 2

[0184]

[0185] 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.

[0186] The specific structures of the compounds used in the following device embodiments and device comparative examples are as follows:

[0187]

[0188]

[0189] Device Example 1

[0190] This embodiment of the device provides an organic electroluminescent device, using the composition provided by the present invention as the red light host material in the organic electroluminescent device. The structure of the organic electroluminescent device is: ITO / HT-1 (20nm) / red light host material (35nm): Ir(piq)3 [10%] / TPBI (10nm) / Alq3 (15nm) / LiF (0.5nm) / Al (150nm). Wherein "Ir(piq)3 [10%]" refers to the doping ratio of the red light dye, that is, the volume ratio of the red light host material to Ir(piq)3 is 90:10.

[0191] The fabrication process of organic electroluminescent devices is as follows:

[0192] (1) The glass plate coated with ITO transparent conductive layer was ultrasonically treated in commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in acetone: ethanol mixed solvent, baked in a clean environment until the moisture was completely removed, cleaned with ultraviolet light and ozone, and bombarded with low-energy cation beam.

[0193] (2) Place the glass substrate with the anode into the vacuum chamber and evacuate to 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.

[0194] (3) A red light host material and dye Ir(piq)3 are vacuum-deposited on the hole transport layer as the light-emitting layer of the organic electroluminescent device. The deposition rate is 0.1 nm / s and the total film thickness is 35 nm. In this embodiment, compound H-1 and compound E-1 are placed in different evaporation sources for heating. The heating rate is controlled so that the volume ratio of the two deposited on the substrate is 1:1, which serves as the red light host material.

[0195] (4) Electron transport layers TPBI and Alq3 are vacuum-deposited sequentially on the light-emitting layer at a deposition rate of 0.1 nm / s and a film thickness of 10 nm and 15 nm, respectively.

[0196] (5) 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.

[0197] Device Examples 2-17

[0198] Device Examples 2-17 each provide an organic electroluminescent device. The only difference between them and Device Example 1 is that the red light host material is different. For details on the selection of the red light host material, please refer to Table 3. The volume ratio of the two components in the red light host material deposited on the substrate is 1:1. Other preparation steps and conditions are the same as those in Device Example 1.

[0199] Device Comparison Examples 1-4

[0200] Comparative Examples 1-4 provide an organic electroluminescent device, which differs from Device Example 1 only in that the first compound and / or the second compound in the red light host material are different. The specific selection of the red light host material is detailed in Table 3. The volume ratio of the two components in the red light host material deposited on the substrate is 1:1. Other preparation steps and conditions are the same as those in Device Example 1.

[0201] Performance testing:

[0202] 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 the initial brightness. In the table below, voltage, efficiency, and LT90 are all relative values. The test results are detailed in Table 3 below.

[0203] Table 3

[0204]

[0205]

[0206] As shown in Table 3, the organic electroluminescent device prepared by using an indole-carbazole compound (first compound) and a second compound in combination in this invention has a lower driving voltage, higher current efficiency and longer lifespan.

[0207] By comparing device embodiments 1-15 and 16-17, if Ar is selected... 21 Ar 22 The sum of the number of benzene rings in the middle compound is selected from the first compound with 4 or more as one of the components of the composition (Device Examples 1-15), which can effectively improve the driving voltage, current efficiency and lifetime of organic electroluminescent devices; if Ar is selected... 21 Ar 22When the sum of the number of benzene rings is selected from the first compound with less than 4 as one of the components of the composition (device examples 16-17), the lifetime of the prepared organic electroluminescent device is reduced, but the current efficiency is improved and the driving voltage is significantly reduced, which is advantageous in applications requiring low voltage.

[0208] As can be seen from Device Examples 2, 13, and 14, by using the deuterated first compound as one of the red light host materials in this invention, the current efficiency and lifetime of the organic electroluminescent device can be further improved. In particular, by using the first compound in which the hydrogen atoms on the intermediate indolocarbazole ring group (obtained by fusion of the group shown in Formula IA with any two adjacent carbon atoms on ring A in the group shown in Formula I) are replaced by deuterium atoms as one of the red light host materials, the performance of the prepared organic electroluminescent device is significantly improved.

[0209] Device Example 18

[0210] This embodiment of the device provides an organic electroluminescent device, using the composition provided by the present invention as the red light host material in the organic electroluminescent device. The structure of the organic electroluminescent device is: 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). Wherein "Ir(piq)3 [10%]" refers to the doping ratio of the red light dye, that is, the volume ratio of the red light host material to Ir(piq)3 is 90:10.

[0211] The fabrication process of organic electroluminescent devices is as follows:

[0212] (1) The glass plate coated with ITO transparent conductive layer was ultrasonically treated in commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in acetone: ethanol mixed solvent, baked in a clean environment until the moisture was completely removed, cleaned with ultraviolet light and ozone, and bombarded with low-energy cation beam.

[0213] (2) Place the glass substrate with the anode into the vacuum chamber and evacuate to 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.

[0214] (3) EB was vacuum-deposited on 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.

[0215] (4) A red light host material and dye Ir(piq)3 are vacuum-deposited on the electron blocking layer as the light-emitting layer of the organic electroluminescent device. The deposition rate is 0.1 nm / s and the total film thickness is 35 nm. In this embodiment, compound H-1 and compound E-1 are placed in different evaporation sources for heating. The heating rate is controlled so that the volume ratio of the two deposited on the substrate is 1:1, which serves as the red light host material.

[0216] (5) Electron transport layers TPBI and Alq3 are vacuum-deposited sequentially on the light-emitting layer at a deposition rate of 0.1 nm / s and a film thickness of 10 nm and 15 nm, respectively.

[0217] (6) 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.

[0218] Device Example 19

[0219] This embodiment of the device provides an organic electroluminescent device, which differs from device embodiment 18 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 of device embodiment 18.

[0220] Device Example 20

[0221] This embodiment of the device provides an organic electroluminescent device, which differs from device embodiment 19 only in that the main material of the light-emitting layer is different (see Table 4 below). The other preparation steps and conditions are the same as those of device embodiment 19.

[0222] The performance testing method is the same as above. The LT90 lifetime test refers to maintaining a constant current density (1000 cd / m²) at room temperature (25–27°C) while keeping the initial brightness constant. 2 The time required for the brightness to decrease to 90% of the initial brightness is shown in the table below. In the table below, voltage, efficiency, and LT90 are all relative values. See Table 4 below for test results.

[0223] Table 4

[0224]

[0225] As can be seen from Table 4, the organic electroluminescent device prepared by using an electron blocking layer material with a specific structure in combination with the red light host material of the composition of the present invention has a lower driving voltage, higher current efficiency and longer lifespan.

[0226] 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 containing an indolocarbazole compound, characterized in that, The composition comprises at least one first compound and at least one second compound; The first compound is obtained by fusion of the group shown in Formula IA with any two adjacent carbon atoms on ring A in the group shown in Formula I; ； Among them, Ar 21 Ar 22 Each is independently selected from any one of phenyl, biphenyl, terphenyl, or tetraphenyl. Indicates the confluence site; The second compound is selected from any one of the following substituted or unsubstituted compounds: ； The substitution refers to the fact that each hydrogen atom in the above compound can be independently replaced by a deuterium atom. In the first compound, each hydrogen atom can be independently replaced by a deuterium atom.

2. The composition according to claim 1, characterized in that, The first compound is selected from any one of the compounds shown in formulas I-1, I-2, and I-3: ； Among them, Ar 21 Ar 22 It has the same scope of protection as claim 1; In the compounds shown in formulas I-1, I-2, and I-3, each hydrogen atom can be independently replaced by a deuterium atom.

3. The composition according to claim 1, characterized in that, The first compound is selected from any one of the compounds shown in formula I-1-D, I-2-D, and I-3-D: ； Among them, Ar 21 Ar 22 It has the same scope of protection as claim 1, and Ar 21 Ar 22 It does not contain deuterium atoms.

4. The composition according to claim 1, characterized in that, The Ar 21 Ar 22 The sum of the number of benzene rings is selected from an integer greater than or equal to 4.

5. The composition according to claim 1, characterized in that, The Ar 21 The Ar is a phenyl group. 22 It is selected from any one of biphenyl, terphenyl, or tetraphenyl.

6. The composition according to claim 1, characterized in that, The Ar 21 It is a biphenyl, and the Ar is... 22 Selected from biphenyl or terphenyl.

7. The composition according to claim 1, characterized in that, The first compound is selected from any one of the following substituted or unsubstituted compounds: ； The substitution refers to the fact that each hydrogen atom in the above compound can be independently replaced by a deuterium atom.

8. The composition according to claim 7, characterized in that, The first compound is selected from any one of the following substituted or unsubstituted compounds H-1 to H-20: ； The substitution refers to the independent replacement of hydrogen atoms in compounds H-1 to H-12 by deuterium atoms.

9. The composition according to claim 8, characterized in that, The first compound is selected from any one of the following compounds: 、 、 、 、 、 、 、 。 10. The composition according to claim 1, characterized in that, The second compound is selected from any one of the following substituted or unsubstituted compounds E-1 to E-10: ； The substitution refers to the independent replacement of hydrogen atoms in compounds E-1 to E-10 by deuterium atoms.

11. The composition according to claim 10, characterized in that, The second compound is selected from any one of the following compounds: 、 、 、 、 、 、 。 12. The composition according to claim 1, characterized in that, In the composition, at least one hydrogen atom in the first compound is replaced by a deuterium atom.

13. The composition according to claim 1, characterized in that, In the composition, at least one hydrogen atom in the first compound is replaced by a deuterium atom, and in the second compound, the hydrogen atom is not replaced by a deuterium atom.

14. 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 1-13.

15. The organic electroluminescent device according to claim 14, characterized in that, The organic thin film layer includes a hole layer and a light-emitting layer; The main material of the light-emitting layer includes the composition as described in any one of claims 1-13.

16. The organic electroluminescent device according to claim 15, characterized in that, The hole layer includes an electron blocking layer, and the material of the electron blocking layer includes spirofluorene compounds; The spirofluorene compound has the specific structure shown in Formula III below: Formula III; Where X is selected from O or S; R 11 R 21 Each is independently selected from hydrogen, deuterium, fluorine, CN, C1~C20 straight-chain or branched alkyl, C1~C20 alkoxy, and C6~C40 aryl; Ar is selected from C6~C40 arylene groups; Ar1 and Ar2 are each independently selected from C6~C40 aryl, C12~C40 oxaaryl, and 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 or 1; m and n are each independently selected from integers between 0 and 4.

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