A composition and organic electroluminescent device

Abstract

The present application provides a kind of composition and organic electroluminescence device.The composition includes at least one first compound and at least one second compound;The first compound has as shown in formula I structure, the second compound has as shown in formula II structure.In the present application, by selecting the first compound with specific formula and the second compound with specific formula are used in coordination, the composition with specific composition is obtained, and the organic electroluminescence device prepared by using the composition as the host material of light-emitting layer has excellent performance.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of organic electroluminescent materials, and particularly relates to a composition and an organic electroluminescent device. BACKGROUND

[0002] With the rapid development of science and technology and information technology, people have put forward new goals and requirements for the performance of information display systems, and display devices with high brightness, high resolution, wide viewing angle and low energy consumption have become research hotspots. Organic electroluminescent (OLED) display technology can meet the above-mentioned needs of people, and has other advantages such as wide working temperature and flexible display, so it has become a new favorite of the new generation of flat panel displays after CRT (Cathode Ray Tube) display, LCD (Liquid Crystal Display) and PDP (Plasma Display) panel displays. At present, organic electroluminescent (OLED) display technology has been applied in the field of smart phones, tablet computers and other fields, and is expanding to large-size application fields such as televisions.

[0003] In the development process in the past 30 years, different designs of organic electroluminescent device structures, optimization of performance such as the service life and efficiency of organic electroluminescent devices, and various excellent OLED materials have attracted widespread attention and research. More types and higher performance materials are urgently needed in the field to meet people's higher requirements for OLED devices. SUMMARY

[0004] In view of the deficiencies of the prior art, the purpose of the present application is to provide a composition and an organic electroluminescent device. In the present application, a composition with a specific composition is obtained by using a first compound with a specific structural formula and a second compound with a specific structural formula in combination, and the composition is used as the host material of the light-emitting layer. The organic electroluminescent device prepared therefrom has excellent performance.

[0005] To achieve this purpose, the present application adopts the following technical solutions:

[0006] In a first aspect, the present application provides a composition, which comprises at least one first compound and at least one second compound.

[0007] The first compound has the structure shown in the following formula I:

[0008]

[0009] wherein Ar 21 , Ar 22 each independently is selected from any one or a combination of at least two of phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl;

[0010] Ar 23any one selected from a single bond, phenylene, naphthylene, bisphenylene, trisphenylene or tetraphenylene;

[0011] The second compound has the following formula II structure:

[0012]

[0013] wherein, Ar 31 , Ar 32 , Ar 33 each independently selected from any one of a single bond, phenylene, bisphenylene, trisphenylene, tetraphenylene or naphthylene;

[0014] X1-X6 are each independently selected from N or CR5, and at least one of X1-X6 is N;

[0015] R1-R5 are each independently H, any one of phenyl, bisphenyl, trisphenyl, tetraphenyl or naphthyl, or a combination of at least two;

[0016] The hydrogen atoms in the first compound and the second compound can each independently be replaced by a deuterium atom (D).

[0017] In the present application, by selecting a first compound having a specific structural formula and a second compound having a specific structural formula, a composition having a specific composition is obtained, and the composition is used as the host material of the light-emitting layer. The organic electroluminescent device prepared has a lower driving voltage, higher current efficiency and longer service life.

[0018] The following is a preferred technical solution of the present application, but not as a limitation on the technical solutions provided by the present application. Through the following preferred technical solution, the purpose and beneficial effects of the present application can be better achieved and realized.

[0019] As a preferred technical solution of the present application, the first compound is selected from a compound represented by formula I-1 or a compound represented by formula I-2:

[0020]

[0021] wherein, Ar 21 , Ar 22 each independently selected from any one of phenyl, bisphenyl, trisphenyl, tetraphenyl or naphthyl, or a combination of at least two;

[0022] The hydrogen atoms in the compound represented by formula I-1 or the compound represented by formula I-2 can each independently be replaced by a deuterium atom.

[0023] Preferably, in the first compound, Ar 21 , Ar22 the hydrogen atoms in the above compounds are each independently replaced by deuterium atoms.

[0024] Preferably, the first compound is selected from a compound represented by formula I-1-D or a compound represented by formula I-2-D:

[0025]

[0026] wherein, Ar 21 , Ar 22 is each independently selected from any one or a combination of at least two of phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl.

[0027] It should be noted that in the compound represented by formula I-1-D or the compound represented by formula I-2-D, (D)4 represents that the four hydrogen atoms on the corresponding benzene ring are each replaced by a deuterium atom, and (D)3 represents that the three hydrogen atoms on the corresponding benzene ring are each replaced by a deuterium atom, and in the compound represented by formula I-1-D or the compound represented by formula I-2-D, Ar 21 , Ar 22 does not contain a deuterium atom.

[0028] As a preferred technical solution of the present application, the sum of the number of benzene rings in Ar 21 , Ar 22 is selected from an integer ≥4, for example, can be 4, 5, 6, 7, or 8, etc.

[0029] Preferably, Ar 21 is a phenyl group, and Ar 22 is selected from any one of biphenyl, terphenyl, or quaterphenyl.

[0030] Preferably, Ar 21 is a biphenyl group, and Ar 22 is selected from biphenyl or terphenyl.

[0031] As a preferred technical solution of the present application, the first compound is selected from any one of the following substituted or unsubstituted compounds:

[0032]

[0033]

[0034] The substitution means that the hydrogen atoms in the above compounds are each independently replaced by deuterium atoms.

[0035] Preferably, the first compound is selected from any one of the following substituted or unsubstituted compounds H-1 to H-28, H101 to H105, H-17o, H-17m, H-101 to H-106:

[0036]

[0037]

[0038]

[0039] The substituent means that the hydrogen atom in the above compound can be independently substituted by a deuterium atom.

[0040] Preferably, the first compound is selected from any one of the following compounds:

[0041]

[0042]

[0043] As a preferred technical scheme of the present application, the Ar 33 is selected from a phenylene group or a single bond.

[0044] Preferably, X1-X3 are all selected from N.

[0045] Preferably, X1-X6 are all selected from N.

[0046] Preferably, X1-X3 are all selected from N, and X4-X6 are independently selected from CR5.

[0047] The R5 has the same protection range as described above.

[0048] Preferably, R1 and R2 are independently selected from a phenyl group or a biphenyl group.

[0049] As a preferred technical scheme of the present application, the second compound is selected from a compound represented by formula II-1:

[0050]

[0051] wherein, Ar 31 , Ar 32 , Ar 33 , X1-X6, R1-R5 have the same protection range as described above.

[0052] As a preferred technical scheme of the present application, the second compound is selected from any one of the following substituted or unsubstituted compounds:

[0053]

[0054]

[0055]

[0056]

[0057] wherein the substitution means that the hydrogen atoms in the above compounds can each independently be replaced with a deuterium atom.

[0058] Preferably, the second compound is selected from any one of the following substituted or unsubstituted compounds:

[0059]

[0060]

[0061] wherein the substitution means that the hydrogen atoms in the above compounds can each independently be replaced with a deuterium atom.

[0062] It should be noted that the preparation method of the first compound and the second compound in the present application is not specially limited, and the commonly used preparation method in the art is applicable.

[0063] In a second aspect, the present application provides an organic electroluminescent device, comprising an anode, a cathode and an organic thin film layer disposed between the anode and the cathode.

[0064] The material of the organic thin film layer comprises the composition as described in the first aspect.

[0065] Preferably, the organic thin film layer comprises a hole layer and a light-emitting layer.

[0066] The host material of the light-emitting layer comprises the composition as described in the first aspect.

[0067] As a preferred technical solution of the present application, the organic thin film layer comprises a hole layer and a light-emitting layer, the light-emitting layer comprises the compound as described in the first aspect, and the hole layer comprises an electron blocking layer, the material of the electron blocking layer comprises a compound having a structure as shown in the following formula A:

[0068]

[0069] wherein R 601 is selected from any one of a tert-butyl-substituted phenyl group, a methylcyclopentyl-substituted phenyl group, a methylcyclohexyl-substituted phenyl group, a methylcyclopentyl group, a methylcyclohexyl group or a tert-butyl group;

[0070] Ring A and ring B are each independently selected from a benzene ring or a naphthalene ring;

[0071] Ar 601 is selected from a phenyl group, a naphthyl group, a phenylene group or a naphthylene group;

[0072] m, n, p are each independently selected from 0 or 1;

[0073] The hydrogen atoms in the compound of formula A can each independently be replaced by a deuterium atom.

[0074] It is to be noted that when m is 1 and n is 1, Ar 601 is selected from phenylene or naphthylene; when m is 0 and n is 1, Ar 601 is selected from phenyl or naphthyl.

[0075] Preferably, the compound of formula A is selected from any one of the following substituted or unsubstituted compounds:

[0076]

[0077]

[0078] The substitution means that the hydrogen atoms in the above-mentioned compounds can each independently be replaced by a deuterium atom.

[0079] Compared with the prior art, the present application has the following beneficial effects:

[0080] (1) In the present application, by selecting the first compound having a specific structure and the second compound having a specific structure, a composition having a specific composition is obtained, and the composition is used as the host material of the light-emitting layer, and the organic electroluminescent device prepared therefrom has a lower driving voltage, a higher current efficiency and a longer service life.

[0081] (2) In the present application, the composition composed of the first compound and the second compound is used as the light-emitting layer host material, and the compound of formula A is used as the electron blocking layer material, which can further improve the performance of the organic electroluminescent device. DETAILED DESCRIPTION

[0082] In order to facilitate the understanding of the present application, the present application is illustrated by the following examples. It should be understood by those skilled in the art that the examples are only to help understand the present application, and should not be regarded as a specific limitation on the present application.

[0083] The specific structures of the compounds used in the following device examples and device comparative examples are as follows:

[0084]

[0085]

[0086] Device Example 1

[0087] The present device example provides an organic electroluminescent device, which selects the composition provided by the present application as the green light host material in the organic electroluminescent device, and the specific composition of the composition is shown in Table 1 below.

[0088] The structure of the organic electroluminescent device is: ITO / HT-1(20 nm) / green host material(35 nm): Ir(ppy)3[10%] / TPBI(10 nm) / Alq3(15 nm) / LiF(0.5 nm) / Al(150 nm). Wherein "Ir(ppy)3[10%]" refers to the doping ratio of green dye, that is, the volume ratio of green host material to Ir(ppy)3 is 90:10.

[0089] The preparation process of the organic electroluminescent device is as follows:

[0090] (1) The glass plate coated with ITO transparent conductive layer is treated with ultrasonic in commercial cleaning agent, washed in deionized water, and then the oil is removed in acetone: ethanol mixed solvent by ultrasonic, baked in a clean environment until the water is completely removed, washed with ultraviolet light and ozone, and the surface is bombarded with low-energy cation beam;

[0091] (2) The glass substrate with anode mentioned above is placed in a vacuum chamber, vacuumized to 1x10 -5 ~ 9x10 -4 Pa, and the hole transport layer HT-1 is vacuum deposited on the anode layer film, the deposition rate is 0.1 nm / s, and the film thickness is 20 nm;

[0092] (3) The green host material and dye Ir(ppy)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, the first compound H-1 and the second compound E-1 are respectively placed in different evaporation sources for heating, the heating speed is controlled so that the volume ratio of the two deposited on the substrate is 1:1, which is used as the green host material.

[0093] (4) The electron transport layer TPBI and Alq3 are vacuum deposited on the light-emitting layer in turn, the deposition rate is 0.1 nm / s, and the film thickness is 10 nm and 15 nm respectively;

[0094] (5) 0.5 nm of LiF and 150 nm of Al are vacuum deposited on the electron transport layer as the electron injection layer and cathode respectively.

[0095] Device examples 2-19

[0096] Device examples 2-19 respectively provide an organic electroluminescent device, which is only different from device example 1 in that the green host material is different, the specific selection of the green host material is shown in Table 1, and the volume ratio of the two components in the green host material deposited on the substrate is 1:1, and the other preparation steps and conditions are the same as those of device example 1.

[0097] Device comparative examples 1-9

[0098] Device comparative examples 1-9 respectively provide an organic electroluminescent device, which is only different from device example 1 in that the first compound and / or the second compound in the green light host material is different, in device comparative examples 5-6, only a single compound is used as the green light host material, the specific selection of the green light host material is shown in Table 1, when there are two components in the green light host, the volume ratio of the two components deposited on the substrate is 1:1, and the other preparation steps and conditions are the same as those of device example 1.

[0099] Performance test:

[0100] The luminance, driving voltage, current efficiency of the prepared organic electroluminescent device were measured by using OLED-1000 multi-channel accelerated aging life and light color performance analysis system test, and the life test LT90 was measured. Among them, the life test LT90 refers to the time required for the luminance to reduce to 90% of the initial luminance under the condition that the current density at the initial luminance is unchanged (herein 1000 cd / m 2 ), at room temperature (25-27℃). In the following table, the voltage, efficiency, LT90 are relative values.

[0101] The test results are shown in the following Table 1.

[0102] Table 1

[0103]

[0104]

[0105] Wherein " / " means that the component does not exist.

[0106] From the content of Table 1, it can be seen that by selecting the first compound and the second compound for use together, a composition is obtained, and the composition is used as the host material of the light-emitting layer, and the organic electroluminescent device prepared has a lower driving voltage, a higher current efficiency and a longer life.

[0107] From the comparison of the relevant data of the device examples and the device comparative examples, it can be seen that in the present application, the first compound with a specific structure and the second compound with a specific structure are used together to obtain a composition with a specific composition, and the composition is used as the host material of the light-emitting layer, which can further improve the comprehensive performance of the organic electroluminescent device, so that it has a lower driving voltage, a higher current efficiency and a longer life.

[0108] Device example 20

[0109] The device example provides an organic electroluminescent device, which uses the composition provided by the present application as the green light host material in the organic electroluminescent device, and the specific composition of the composition is shown in Table 2.

[0110] The structure of the organic electroluminescent device is: ITO / HT-1(20 nm) / electron blocking layer(5 nm) / green host material(35 nm): Ir(ppy)3[10%] / TPBI(10 nm) / Alq3(15 nm) / LiF(0.5 nm) / Al(150 nm). Wherein "Ir(ppy)3[10%]" refers to the doping ratio of green dye, i.e. the volume ratio of green host material to Ir(ppy)3 is 90:10.

[0111] The preparation process of the organic electroluminescent device is as follows:

[0112] (1) The glass plate coated with ITO transparent conductive layer is treated with ultrasonic in commercial cleaning agent, washed in deionized water, ultrasonic deoiled in acetone: ethanol mixed solvent, baked in clean environment until completely removing water, cleaned with ultraviolet light and ozone, and the surface is bombarded with low-energy cation beam;

[0113] (2) The glass substrate with anode above is placed in a vacuum chamber, vacuumed to 1x10 -5 ~ 9x10 -4 Pa, and the hole transport layer HT-1 is vacuum deposited on the anode layer film at a deposition rate of 0.1 nm / s and a film thickness of 20 nm;

[0114] (3) The EB-1 is vacuum deposited as an electron blocking layer on the hole transport layer at a deposition rate of 0.1 nm / s and a film thickness of 5 nm;

[0115] (4) The green host material and dye Ir(ppy)3 are vacuum deposited as the light-emitting layer of the organic electroluminescent device on the electron blocking layer at a deposition rate of 0.1 nm / s and a total film thickness of 35 nm; in this embodiment, the first compound H-1 and the second compound E-1 are respectively placed in different evaporation sources for heating, and the heating speed is controlled so that the volume ratio of the two deposited on the substrate is 1:1 as the green host material.

[0116] (5) The electron transport layer TPBI and Alq3 are vacuum deposited in sequence 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;

[0117] (6) 0.5 nm of LiF and 150 nm of Al are vacuum deposited on the electron transport layer as the electron injection layer and the cathode, respectively.

[0118] Device Examples 21-23

[0119] Device embodiments 21-23 provide an organic electroluminescent device, which is only different from device embodiment 20 in that the electron blocking layer material or / and the light-emitting layer host material is different (see Table 2 below for details), and other preparation steps, conditions are the same as those of device embodiment 20.

[0120] Performance test:

[0121] The luminance, driving voltage, current efficiency of the prepared organic electroluminescent device were measured by using OLED-1000 multi-channel accelerated aging life and light color performance analysis system test, and the life test LT90 was also measured. Among them, the life test LT90 refers to the time required for the luminance to reduce to 90% of the initial luminance under the condition that the current density is kept unchanged (herein 1000 cd / m 2 ), at room temperature (25-27℃), and the initial luminance. In the following table, the voltage, efficiency, LT90 are all relative values.

[0122] The test results are shown in Table 2 below.

[0123] Table 2

[0124]

[0125] From the content of Table 2, it can be seen that by the mutual cooperation of the first compound with a specific structure and the second compound with a specific structure in the present application, a composition with a specific composition is obtained, and the use of an electron blocking layer material with a specific structure can further improve the comprehensive performance of the organic electroluminescent device, so that it has a lower driving voltage, higher current efficiency and longer life.

[0126] The applicant declares that the above embodiments are used to illustrate the detailed process flow of the present application, but the present application is not limited to the above detailed process flow, that is, it does not mean that the present application must rely on the above detailed process flow to be implemented. It should be understood by those skilled in the art that any improvement on the present application, equivalent replacement of each raw material of the product of the present application, addition of auxiliary ingredients, selection of specific methods, etc. fall within the scope of protection and disclosure of the present application.

Claims

1. 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 organic thin film layer includes a hole layer and a light-emitting layer; The main material of the light-emitting layer includes a composition comprising at least one first compound and at least one second compound; The first compound is selected from the formula The compound or formula shown in -1 Compound shown in -2: ； Among them, Ar 21 Ar 22 Each is independently selected from any one or at least a combination of two of phenyl, diphenyl, triphenyl, tetraphenyl, and naphthyl; The second compound has the structure shown in Formula II: Formula II; Among them, Ar 31 Ar 32 Each is independently selected from any one of single bond, phenylene, diphenylene, terphenylene, tetraphenylene, or naphthylene; The Ar 33 Selected from phenylene or single bonds; X1~X6 are each independently selected from N or CR5, and X1~X3 are all selected from N; R1 to R5 are each independently any one or at least two of H, phenyl, diphenyl, triphenyl, tetraphenyl, and naphthyl; In both the first and second compounds, hydrogen atoms can be independently replaced by deuterium atoms; The hole layer includes an electron blocking layer, and the material of the electron blocking layer includes a compound having the structure shown in Formula A: Formula A; Among them, R 601 Selected from any one of tert-butyl-substituted phenyl, methylcyclopentyl-substituted phenyl, and methylcyclohexyl-substituted phenyl; Ring A and ring B are each independently selected from the benzene ring; Ar 601 Selected from phenyl, naphthyl, phenylene, or naphthylene; m is selected from 1; n and p are each independently selected from 0; In compound A, each hydrogen atom can be independently replaced by a deuterium atom.

2. The organic electroluminescent device according to claim 1, characterized in that, Ar in the first compound 21 Ar 22 Each hydrogen atom in the atom is independently replaced by a deuterium atom.

3. The organic electroluminescent device according to claim 1, characterized in that, The first compound is selected from the formula The compound or formula shown in -1-D The compound shown in -2-D: ； Among them, Ar 21 Ar 22 Each is independently selected from any one or a combination of at least two of phenyl, diphenyl, triphenyl, tetraphenyl, and naphthyl.

4. The organic electroluminescent device 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 of ≥4.

5. The organic electroluminescent device according to claim 1, characterized in that, The Ar 21 The Ar is phenyl. 22 It is selected from any one of diphenyl, triphenyl, or tetraphenyl.

6. The organic electroluminescent device according to claim 1, characterized in that, The Ar 21 It is a diphenyl group, and the Ar is... 22 Selected from diphenyl or triphenyl.

7. The organic electroluminescent device 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 organic electroluminescent device according to claim 7, characterized in that, The first compound is selected from any one of the following substituted or unsubstituted compounds: H-1~H-28, H-17o, H-17m, H-101~H-106. ； The substitution refers to the fact that each hydrogen atom in the above compound can be independently replaced by a deuterium atom.

9. The organic electroluminescent device according to claim 1, characterized in that, X1 to X6 are all selected from N.

10. The organic electroluminescent device according to claim 1, characterized in that, X1 to X3 are all selected from N, and X4 to X6 are each independently selected from CR5, wherein CR5 has the same protection scope as claim 1.

11. The organic electroluminescent device according to claim 1, characterized in that, R1 and R2 are each independently selected from phenyl or diphenyl.

12. The organic electroluminescent device according to claim 1, characterized in that, The second compound is selected from the compound shown in Formula II-1: ； Among them, Ar 31 Ar 32 X1~X6 and R1~R4 have the same protection scope as claim 1.

13. 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 organic thin film layer includes a hole layer and a light-emitting layer; The main material of the light-emitting layer includes a composition comprising at least one first compound and at least one second compound; The first compound is selected from the formula The compound or formula shown in -1 Compound shown in -2: ； Among them, Ar 21 Ar 22 Each is independently selected from any one or at least a combination of two of phenyl, diphenyl, triphenyl, tetraphenyl, and naphthyl; The second compound is selected from any one of the following substituted or unsubstituted compounds: ； Wherein, the substitution means that each hydrogen atom in the above compound can be independently replaced by a deuterium atom; The hole layer includes an electron blocking layer, and the material of the electron blocking layer includes a compound having the structure shown in Formula A: Formula A; Among them, R 601 Selected from any one of tert-butyl-substituted phenyl, methylcyclopentyl-substituted phenyl, and methylcyclohexyl-substituted phenyl; Ring A and ring B are each independently selected from the benzene ring; Ar 601 Selected from phenyl, naphthyl, phenylene, or naphthylene; m is selected from 1; n and p are each independently selected from 0; In compound A, each hydrogen atom can be independently replaced by a deuterium atom.

14. The organic electroluminescent device according to claim 13, characterized in that, 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.

15. The organic electroluminescent device according to any one of claims 1-14, characterized in that, The compound of formula A 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.

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