Laminated organic light-emitting device, display panel and display device

Abstract

The invention relates to the technical field of organic electroluminescence, in particular to a laminated organic electroluminescence device, a display panel and a display device. Compared with the prior art, the compound shown in the formula (I) has anisotropy and / or has a low refractive index and / or contains a functional group with large steric hindrance, so that the compound has a better hole injection effect and a slower transverse mobility; the compound which is good in hole injection effect and slow in transverse mobility and is shown in the formula (I) is used as a main body material of the P-type charge generation layer, so that transverse leakage current of the charge generation layer is reduced; meanwhile, a leakage flow regulation and control layer containing a compound shown in the formula (I) is arranged between a hole transport layer and a light-emitting layer of the light-emitting unit, so that the effects of reducing leakage flow and balancing current carriers are achieved, the transverse leakage flow of the laminated organic light-emitting device is reduced, the low-gray-scale visual effect is improved, and the overall efficiency of the device can be improved; moreover, the laminated organic light-emitting device has mass production conditions, and large-scale production can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic electroluminescence, in particular to a stacked organic electroluminescence device, a display panel and a display device. BACKGROUND

[0002] As a new generation of display technology, the organic electroluminescence device (OLED) has the advantages of ultra-thin, self-luminescence, wide viewing angle, fast response, high luminous efficiency, good temperature adaptability, simple production process, low driving voltage, low energy consumption, etc., and has been widely used in flat panel display, flexible display, solid state lighting and vehicle display industries.

[0003] According to the luminescence mechanism, OLEDs can be divided into electrophosphorescence and electrophosphorescence. Fluorescence is a single-excitation-state excimer radiative decay transition, and phosphorescence is the light emitted by the decay of a three-excitation-state excimer to the ground state. According to the spin quantum statistics theory, the formation probability ratio of single-excitation-state and three-excitation-state is 1:3. In fluorescent materials, only single-excitation-state can be used for light emission, and three-excitation-state cannot be effectively utilized, so the upper limit of internal quantum efficiency is 25%, and the external quantum efficiency is generally less than 5%. The internal quantum efficiency of electrophosphorescent material is theoretically 100%, and the external quantum efficiency can reach 20%. In 1998, Professor Ma Yuqing of Jilin University and Professor Forrest of Princeton University in the United States reported the use of osmium and platinum complexes as dyes doped into the light-emitting layer, which was the first successful preparation and explanation of the phosphorescent electroluminescence phenomenon, and pioneered the application of phosphorescent materials in electroluminescent devices.

[0004] Organic light-emitting devices can form various structures, and stacked organic light-emitting devices are one of them. In a tandem device, a light-emitting unit containing a light-emitting layer is stacked between an anode and a cathode. There is a charge generation layer between adjacent light-emitting parts for charge generation and movement, and the charge generation layer needs low driving voltage and high efficiency.

[0005] However, the current stacked device charge generation layer material has less selectivity, and has problems such as high driving voltage and low efficiency, the main reasons being the material itself and poor energy level matching of adjacent layers; in addition, the charge generation layer film has strong lateral transmission ability and large lateral leakage, and the product is prone to steal light, resulting in low product efficiency and other adverse problems. SUMMARY

[0006] In view of the above problems, the present application provides a stacked organic electroluminescence device, a display panel and a display device to reduce lateral leakage and improve low gray scale visual effect. The specific scheme is as follows:

[0007] The present application provides a stacked organic electroluminescence device, comprising:

[0008] an anode;

[0009] cathode;

[0010] A light-emitting units stacked between the anode and the cathode; A is an integer greater than or equal to 2;

[0011] a hole injection layer disposed between the anode and a light-emitting unit adjacent to the anode among the A light-emitting units;

[0012] an electron injection layer disposed between the cathode and a light-emitting unit adjacent to the cathode among the A light-emitting units;

[0013] a charge generation layer disposed between every two adjacent light-emitting units among the A light-emitting units;

[0014] Each charge generation layer includes an N-type charge generation layer and a P-type charge generation layer stacked in sequence from the anode to the cathode;

[0015] The P-type charge generation layer comprises a compound represented by formula (I) and a P-type dopant material;

[0016] Each light-emitting unit includes a hole transport layer, a light-emitting layer, and an electron transport layer stacked in sequence from the anode to the cathode; and a leakage current regulating layer is provided between the hole transport layer and the light-emitting layer of at least one light-emitting unit among the A light-emitting units;

[0017] The leakage regulating layer includes a compound represented by formula (I):

[0018]

[0019] wherein n1, m1 and p1 are each independently selected from integers ranging from 0 to 3;

[0020] The L1 to L3 are linking groups, each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted C10-C30 fused ring aromatic group; the R1 to R3 are each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fused ring group, a substituted or unsubstituted C5-C30 spirocyclic group, a substituted or unsubstituted tetraphenylsilyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups via a single bond, and at least one of the above groups is not a substituted or unsubstituted phenyl group; or any two of the R1 to R3 are connected by a single bond; the fused ring group is formed by condensing at least two of a monocyclic aromatic group, a monocyclic alicyclic hydrocarbon group, and a monocyclic heterocyclic group;

[0021] The substituents in the substituted phenyl group, substituted C10-C30 fused ring aromatic group, substituted fused ring group, substituted diphenylamino group, substituted C5-C30 spirocyclic group, substituted tetraphenylsilyl group and substituted tetraphenylmethane group in formula (I) are each independently selected from one or more of halogen, C1-C10 alkyl group, C1-C10 fluoroalkyl group, C5-C20 alicyclic hydrocarbon group, phenyl group and substituted phenyl group.

[0022] The present application also provides a display panel comprising the above-mentioned stacked organic electroluminescent device.

[0023] The present application also provides a display device, comprising the above-mentioned display panel.

[0024] The present invention provides a stacked organic electroluminescent device. Compared with the prior art, the compound represented by formula (I) has anisotropy and / or has a low refractive index and / or contains functional groups with large steric hindrance, so that it has a good hole injection effect and a slow lateral mobility. The present invention uses the compound represented by formula (I), which is a material with good hole injection effect and slow lateral mobility, as the main material of a P-type charge generation layer, thereby reducing the lateral leakage of the charge generation layer. At the same time, a leakage control layer comprising the compound represented by formula (I) is provided between the hole transport layer and the light-emitting layer of the light-emitting unit, thereby reducing the leakage and balancing the carriers. This not only reduces the lateral leakage of the stacked organic electroluminescent device and improves the low-grayscale visual effect, but also improves the overall efficiency of the device. In addition, the stacked organic electroluminescent device is suitable for mass production and can be produced on a large scale.

[0025] Furthermore, the present invention uses the compound represented by formula (II) to prepare a hole transport layer in contact with the leakage current regulation layer, which has fast injection and fast transport characteristics and can further reduce the device voltage.

[0026] Furthermore, the present invention uses the compound represented by formula (I) as the main material of the hole injection layer, which can further reduce the lateral leakage of the device and improve the device efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and other features, advantages, and aspects of the various embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. Throughout the drawings, the same or similar reference numerals represent the same or similar elements. It should be understood that the drawings are schematic and that the originals and elements are not necessarily drawn to scale.

[0028] Figure 1 A schematic structural diagram of a stacked organic electroluminescent device provided by the present invention;

[0029] Figure 2 A schematic structural diagram of a light-emitting unit in a stacked organic electroluminescent device provided by the present invention that does not contain a leakage current regulating layer;

[0030] Figure 3 A schematic structural diagram of a light-emitting unit containing a leakage current regulating layer in a stacked organic electroluminescent device provided by the present invention;

[0031] Figure 4 A schematic structural diagram of a light-emitting unit containing a leakage current regulating layer in a stacked organic electroluminescent device provided by the present invention;

[0032] Figure 5 A schematic structural diagram of a stacked organic electroluminescent device provided by the present invention;

[0033] Figure 6 A schematic structural diagram of the stacked organic electroluminescent device provided in Example 1;

[0034] Figure 7 A schematic structural diagram of a stacked organic electroluminescent device provided in Example 13;

[0035] Figure 8 A schematic diagram of a substrate structure selected for leakage current testing provided in some embodiments of the present application. DETAILED DESCRIPTION

[0036] The following will be combined with the accompanying drawings in the embodiments of this application to clearly and completely describe the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0037] It will be apparent to those skilled in the art that various modifications and variations can be made in this application without departing from the spirit or scope of this application. Therefore, this application is intended to cover modifications and variations of this application that fall within the scope of the corresponding claims (technical solutions claimed for protection) and their equivalents. It should be noted that the embodiments provided in the examples of this application can be combined with each other without contradiction.

[0038] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0039] The present invention provides a stacked organic electroluminescent device, comprising:

[0040] anode;

[0041] cathode;

[0042] A light-emitting units stacked between the anode and the cathode; A is an integer greater than or equal to 2;

[0043] a hole injection layer disposed between the anode and a light-emitting unit adjacent to the anode among the A light-emitting units;

[0044] an electron injection layer disposed between the cathode and a light-emitting unit adjacent to the cathode among the A light-emitting units;

[0045] a charge generation layer disposed between every two adjacent light-emitting units among the A light-emitting units;

[0046] Each charge generation layer includes an N-type charge generation layer and a P-type charge generation layer stacked in sequence from the anode to the cathode;

[0047] The P-type charge generation layer comprises a compound represented by formula (I) and a P-type dopant material;

[0048] Each light-emitting unit includes a hole transport layer, a light-emitting layer and an electron transport layer stacked in sequence from the anode to the cathode; and a leakage current regulating layer is provided between the hole transport layer and the light-emitting layer of at least one light-emitting unit in the A light-emitting units.

[0049] See also Figure 1 , Figure 1 Schematic diagram of the structure of the stacked organic electroluminescent device provided by the present invention, wherein 1 is the cathode, 2 is the electron injection layer, 3 is the light-emitting unit, 4 is the P-type charge generation layer, 5 is the N-type charge generation layer, 6 is the light-emitting unit, 7 is the hole injection layer, and 8 is the anode.

[0050] See also Figure 2 , Figure 2 This is a schematic structural diagram of a light-emitting unit in a stacked organic electroluminescent device provided by the present invention that does not contain a leakage current regulation layer, wherein 3-1 is a hole transport layer, 3-2 is a light-emitting layer, and 3-3 is an electron transport layer.

[0051] See also Figure 3 , Figure 3 This is a schematic structural diagram of a light-emitting unit containing a leakage current regulation layer in a stacked organic electroluminescent device provided by the present invention, wherein 3-1 is a hole transport layer, 3-2 is a light-emitting layer, 3-3 is an electron transport layer, and 3-4 is a leakage current regulation layer.

[0052] The leakage regulating layer includes a compound represented by formula (I):

[0053]

[0054] wherein n1, m1 and p1 are each independently selected from integers ranging from 0 to 3;

[0055] The L1 to L3 are linking groups, each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted C10-C30 fused ring aromatic group; the R1 to R3 are each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fused ring group, a substituted or unsubstituted C5-C30 spirocyclic group, a substituted or unsubstituted tetraphenylsilyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups via a single bond, and at least one of the above groups is not a substituted or unsubstituted phenyl group; or any two of the R1 to R3 are connected by a single bond; the fused ring group is formed by condensing at least two of a monocyclic aromatic group, a monocyclic alicyclic hydrocarbon group, and a monocyclic heterocyclic group;

[0056] The substituents in the substituted phenyl, substituted C10-C30 fused ring group, substituted fused ring group, substituted diphenylamino group, substituted C5-C30 spirocyclic group, substituted tetraphenylsilyl group and substituted tetraphenylmethane group in formula (I) are independently selected from one or more of halogen, C1-C10 alkyl, C1-C10 fluoroalkyl, C5-C20 alicyclic hydrocarbon group, phenyl group and substituted phenyl group; specifically, the substituents are independently selected from one or more of halogen, C1-C6 alkyl, C1-C6 fluoroalkyl, C5-C15 alicyclic hydrocarbon group, phenyl group and substituted phenyl group. More specifically, they are each independently selected from one or more of halogen, C1-C4 alkyl, C1-C4 fluoroalkyl, C6-C10 alicyclic hydrocarbon, phenyl and substituted phenyl; Still more specifically, they are each independently selected from one or more of halogen, C1-C2 alkyl, C1-C2 fluoroalkyl, C6-C10 alicyclic hydrocarbon, phenyl and substituted phenyl; wherein the number of fluorine atoms in the fluoroalkyl group may be more than one or more, and there is no special limitation. Specifically, the fluoroalkyl group is a perfluoroalkyl group.

[0057] More specifically, the substituents in the substituted phenyl group, substituted C10-C30 fused ring group, substituted fused ring group, substituted diphenylamino group, substituted C5-C30 spirocyclic group, substituted tetraphenylsilyl group and substituted tetraphenylmethane group in formula (I) are each independently selected from one or more of fluorine, methyl, tert-butyl, fluoromethyl, cyclohexyl, adamantyl, phenyl, tolyl, xylyl, fluoromethylphenyl and tert-butylphenyl.

[0058] In the present invention, L1 to L3 are linking groups. In a specific embodiment provided by the present invention, specifically, L1 to L3 are each independently selected from substituted or unsubstituted phenyl, substituted or unsubstituted C10 to C20 fused ring aromatic group; the substituents in the substituted phenyl and substituted C10 to 20 fused ring aromatic group are each independently selected from one or more of halogen, C1 to C10 alkyl, C1 to C10 fluoroalkyl, C5 to C20 alicyclic hydrocarbon group, phenyl and substituted phenyl, specifically, each independently selected from halogen, C1 to C6 alkyl, C1 to C6 fluoroalkyl, C5 to C15 alicyclic hydrocarbon group, phenyl More specifically, each is independently selected from one or more of halogen, C1-C4 alkyl, C1-C4 fluoroalkyl, C6-C10 alicyclic hydrocarbon group, phenyl and substituted phenyl; More specifically, each is independently selected from one or more of halogen, C1-C2 alkyl, C1-C2 fluoroalkyl, C6-C10 alicyclic hydrocarbon group, phenyl and substituted phenyl; More specifically, each is independently selected from one or more of fluorine, methyl, tert-butyl, fluoromethyl, cyclohexyl, adamantyl, phenyl, tolyl, xylyl, fluoromethylphenyl and tert-butylphenyl.

[0059] More specifically, L1 to L3 are each independently selected from substituted or unsubstituted phenyl, substituted or unsubstituted C10-C14 fused ring aromatic group; the substituents in the substituted phenyl and substituted C10-C14 fused ring aromatic group are each independently selected from one or more of halogen, C1-C10 alkyl, C1-C10 fluoroalkyl, C5-C20 alicyclic hydrocarbon group, phenyl and substituted phenyl group, specifically, each independently selected from one or more of halogen, C1-C6 alkyl, C1-C6 fluoroalkyl, C5-C15 alicyclic hydrocarbon group, phenyl and substituted phenyl group; More specifically, each is independently selected from one or more of halogen, C1-C4 alkyl, C1-C4 fluoroalkyl, C6-C10 alicyclic hydrocarbon, phenyl and substituted phenyl; more specifically, each is independently selected from one or more of halogen, C1-C2 alkyl, C1-C2 fluoroalkyl, C6-C10 alicyclic hydrocarbon, phenyl and substituted phenyl; more specifically, each is independently selected from one or more of fluorine, methyl, tert-butyl, fluoromethyl, cyclohexyl, adamantyl, phenyl, tolyl, xylyl, fluoromethylphenyl and tert-butylphenyl.

[0060] More specifically, the L1 to L3 are each independently selected from substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl; the substituents in the substituted phenyl and substituted naphthyl are each independently selected from one or more of halogen, C1 to C10 alkyl, C1 to C10 fluoroalkyl, C5 to C20 alicyclic hydrocarbon, phenyl and substituted phenyl; specifically, each is independently selected from one or more of halogen, C1 to C6 alkyl, C1 to C6 fluoroalkyl, C5 to C15 alicyclic hydrocarbon, phenyl and substituted phenyl; further specifically, each is independently selected from one or more of halogen, C1 to C6 alkyl, C1 to C6 fluoroalkyl, C5 to C15 alicyclic hydrocarbon, phenyl and substituted phenyl; Specifically, each is independently selected from one or more of halogen, C1-C4 alkyl, C1-C4 fluoroalkyl, C6-C10 alicyclic hydrocarbon, phenyl and substituted phenyl; more specifically, each is independently selected from one or more of halogen, C1-C2 alkyl, C1-C2 fluoroalkyl, C6-C10 alicyclic hydrocarbon, phenyl and substituted phenyl; more specifically, each is independently selected from one or more of fluorine, methyl, tert-butyl, fluoromethyl, cyclohexyl, adamantyl, phenyl, tolyl, xylyl, fluoromethylphenyl and tert-butylphenyl.

[0061] In the present invention, n1, m1 and p1 are the numbers of linking groups. In a specific embodiment provided by the present invention, optionally, n1, m1 and p1 are each independently selected from 0, 1, 2 or 3.

[0062] In a specific embodiment provided by the present invention, optionally, n1, m1 and p1 are each independently selected from 0, 1 or 2.

[0063] In one embodiment, R1-R3are each independently selected from substituted or unsubstituted phenyl, substituted or unsubstituted diphenylamine, substituted or unsubstituted fused ring group, substituted or unsubstituted C5-C20spirocyclic group, substituted or unsubstituted tetraphenylsilane group, substituted or unsubstituted tetraphenylmethane group, or a group formed by linking any two of R1-R3by a single bond; when any two of R1-R3are linked by a single bond, the number of linking groups corresponding thereto is 0; the substituents in the substituted phenyl, substituted diphenylamine, substituted fused ring group, substituted C5-C20spirocyclic group, substituted tetraphenylsilane group, and substituted tetraphenylmethane group are each independently selected from one or more of halogen, C1-C10alkyl, C1-C10fluoroalkyl, C5-C20alicyclic group, phenyl, and substituted phenyl; specifically, each is independently selected from one or more of halogen, C1-C6alkyl, C1-C6fluoroalkyl, C5-C15alicyclic group, phenyl, and substituted phenyl; more specifically, each is independently selected from one or more of halogen, C1-C4alkyl, C1-C4fluoroalkyl, C6-C10alicyclic group, phenyl, and substituted phenyl; more specifically, each is independently selected from one or more of halogen, C1-C2alkyl, C1-C2fluoroalkyl, C6-C10alicyclic group, phenyl, and substituted phenyl; more specifically, each is independently selected from one or more of fluorine, methyl, t-butyl, fluoromethyl, cyclohexane group, adamantane group, phenyl, tolyl, xylyl, fluoromethylphenyl, and t-butylphenyl.

[0064] In one embodiment, the fused ring group is formed by fusing at least two of monocyclic aryl, monocyclic aliphatic group, and monocyclic heterocyclic group; the number of monocyclic rings in the fused ring group can be specifically an integer from 2 to 10; optionally, the number of monocyclic rings in the fused ring group is 2, 3, 4, 5, 6, 7, 8, 9, 10, or an integer between any two of the foregoing ranges; in some embodiments, the number of monocyclic rings in the fused ring group is 3, 4, 5, 6, or 7; the monocyclic aryl can be specifically a six-membered monocyclic aryl; the monocyclic aliphatic group can be specifically one or more of three-membered monocyclic aliphatic group, four-membered monocyclic aliphatic group, five-membered monocyclic aliphatic group, and six-membered monocyclic aliphatic group; the monocyclic aliphatic group can be a saturated monocyclic aliphatic group or an unsaturated monocyclic aliphatic group, without specific limitation; the monocyclic heterocyclic group can be specifically one or more of three-membered monocyclic heterocyclic group, four-membered monocyclic heterocyclic group, five-membered monocyclic heterocyclic group, and six-membered monocyclic heterocyclic group; the heteroatom in the monocyclic heterocyclic group can be any heteroatom known to those skilled in the art, without specific limitation, and can be specifically one or more of N, O, S, and Si.

[0065] More specifically, the R1 to R3 are each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fused ring group, a substituted or unsubstituted spirobifluorenyl group, a substituted or unsubstituted tetraphenylsilyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups by a single bond, and at least one is not a substituted or unsubstituted phenyl group; or any two of the R1 to R3 are connected to the N atom by a single bond to form a nitrogen-containing five-membered heterocyclic ring; when any two of the R1 to R3 are connected by a single bond, the number of the corresponding connecting groups is 0; the substituents in the substituted phenyl group, the substituted diphenylamino group, the substituted fused ring group, the substituted spirobifluorenyl group, the substituted tetraphenylsilyl group and the substituted tetraphenylmethane group are each independently selected from halogen, C1-C10 alkyl, C1-C10 fluoroalkyl, C C5-C20 alicyclic hydrocarbon group, phenyl group and substituted phenyl group; specifically, each independently selected from one or more of halogen, C1-C6 alkyl group, C1-C6 fluoroalkyl group, C5-C15 alicyclic hydrocarbon group, phenyl group and substituted phenyl group; further specifically, each independently selected from one or more of halogen, C1-C4 alkyl group, C1-C4 fluoroalkyl group, C6-C10 alicyclic hydrocarbon group, phenyl group and substituted phenyl group; further specifically, each independently selected from one or more of halogen, C1-C2 alkyl group, C1-C2 fluoroalkyl group, C6-C10 alicyclic hydrocarbon group, phenyl group and substituted phenyl group; further specifically, each independently selected from one or more of fluorine, methyl, tert-butyl, fluoromethyl, cyclohexyl, adamantyl, phenyl, tolyl, xylyl, fluoromethylphenyl and tert-butylphenyl.

[0066] More specifically, the R1 to R3 are each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted dibenzopyrrolyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophenyl group, a seven-ring fused ring group, a substituted or unsubstituted spirobifluorenyl group, a substituted or unsubstituted tetraphenylsilyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups by a single bond, and at least one It is not a substituted or unsubstituted phenyl group; or any two of the R1 to R3 are connected to the N atom by a single bond to form a nitrogen-containing five-membered heterocyclic ring; when any two of the R1 to R3 are connected by a single bond, the number of the corresponding connecting groups is 0; the substituted phenyl, substituted diphenylamino, substituted fluorenyl, substituted dibenzopyrrolyl, substituted dibenzofuranyl, substituted dibenzothiophene, substituted spirobifluorenyl, substituted tetraphenylsilyl and substituted tetraphenylmethane The substituents in are each independently selected from one or more of halogen, C1-C10 alkyl, C1-C10 fluoroalkyl, C5-C20 alicyclic hydrocarbon group, phenyl and substituted phenyl; specifically, they are each independently selected from one or more of halogen, C1-C6 alkyl, C1-C6 fluoroalkyl, C5-C15 alicyclic hydrocarbon group, phenyl and substituted phenyl; further specifically, they are each independently selected from one or more of halogen, C1-C4 alkyl, C1-C4 fluoroalkyl, C6-C10 alicyclic hydrocarbon group, phenyl and substituted phenyl; further specifically, they are each independently selected from one or more of halogen, C1-C2 alkyl, C1-C2 fluoroalkyl, C6-C10 alicyclic hydrocarbon group, phenyl and substituted phenyl; further specifically, they are each independently selected from one or more of fluorine, methyl, tert-butyl, fluoromethyl, cyclohexyl, adamantyl, phenyl, tolyl, xylyl, fluoromethylphenyl and tert-butylphenyl. The seven-ring fused ring group is specifically formed by condensing any two of a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted dibenzopyrrolyl group, a substituted or unsubstituted dibenzofuranyl group and a substituted or unsubstituted dibenzothienyl group through a monocyclic heterocyclic group; the heteroatom in the monocyclic heterocyclic group is selected from one or more of N, O, S and Si.

[0067] In a specific embodiment provided by the present invention, any two of R1 to R3 are connected to the N atom through a single bond to form a nitrogen-containing five-membered heterocyclic ring; that is, two carbon atoms of any substituent in R1 to R3, two carbon atoms in any other two substituents and the central N atom form a nitrogen-containing five-membered heterocyclic ring, such as two carbon atoms in R1, two carbon atoms in R2 and the central N atom form a nitrogen-containing five-membered heterocyclic ring.

[0068] In a specific embodiment provided by the present invention, the leakage regulating layer includes one or more compounds selected from the group consisting of LHT-1 to LHT-96:

[0069]

[0070]

[0071]

[0072]

[0073] In a specific embodiment provided by the present invention, the thickness of the leakage control layer can be specifically 3 to 30 nm; optionally, the thickness of the leakage control layer is 3 nm, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm or a range between any two of the above values.

[0074] According to the present invention, the number of light-emitting units provided with a leakage current regulation layer may be one or more, that is, any integer less than or equal to A; in a specific embodiment provided by the present invention, when the number of the leakage current regulation layers is less than the number of light-emitting units, that is, when the number of the leakage current regulation layers is any integer from 1 to A-1, the leakage current regulation layer is arranged in the light-emitting unit that is not in contact with the hole injection layer.

[0075] In a specific embodiment provided by the present invention, a leakage current regulating layer is provided between the hole transport layer and the light-emitting layer of A-1 light-emitting units or A light-emitting units among the A light-emitting units.

[0076] In a specific embodiment provided by the present invention, A is any integer greater than or equal to 2, which can be selected according to needs; specifically, it can be an integer of 2 to 10; more specifically, it can be an integer of 2 to 8; more specifically, it can be an integer of 2 to 6; more specifically, it can be an integer of 2 to 4; more specifically, it can be 2 or 3.

[0077] In a specific embodiment provided by the present invention, the hole transport layer in contact with the leakage control layer in the A light-emitting units includes a compound represented by formula (II); the HOMO energy difference between the compound represented by formula (II) and the compound represented by formula (I) is less than or equal to 0.3 eV, and the refractive index of the compound represented by formula (I) is lower than that of the hole transport layer; if the HOMO energy level difference between the compound represented by formula (II) and the compound represented by formula (I) is ≤0.3 ev, it is easier to inject carriers into the LHT; otherwise, if it is greater than 0.3 ev, carrier injection is difficult, the voltage will increase, and some of the carriers will accumulate at the interface between the two materials, which will also destroy the stability of the material; the compound represented by formula (II) with a suitable energy level can make the hole transport layer have the characteristics of fast injection and fast transport, which can further reduce the device voltage.

[0078]

[0079] wherein n2, m2 and p2 are each independently selected from integers of 0 to 3.

[0080] In a specific embodiment provided by the present invention, optionally, n2, m2 and p2 are each independently selected from 0, 1 or 2.

[0081] The L4 to L6 are linking groups, each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted C10-C30 fused ring aromatic group; the substituents in the substituted phenyl group and the substituted C10-C30 fused ring group are each independently selected from one or more of a C1-C10 alkyl group, a phenyl group and a substituted phenyl group; specifically, each independently selected from one or more of a C1-C6 alkyl group, a phenyl group and a substituted phenyl group; further specifically, each independently selected from one or more of a C1-C4 alkyl group, a phenyl group and a substituted phenyl group; further specifically, each independently selected from one or more of a C1-C2 alkyl group, a phenyl group and a substituted phenyl group; further specifically, each independently selected from one or more of a methyl group, a tert-butyl group, a phenyl group, a tolyl group, a xylyl group and a tert-butylphenyl group.

[0082] In a specific embodiment provided by the present application, specifically, each of L4to L6is independently selected from substituted or unsubstituted phenyl, substituted or unsubstituted C10-C20fused ring aryl; each of the substituents in the substituted phenyl and substituted C10-C20fused ring aryl is independently selected from one or more of C1-C10alkyl, phenyl and substituted phenyl; specifically, each of the substituents is independently selected from one or more of C1-C6alkyl, phenyl and substituted phenyl; further specifically, each of the substituents is independently selected from one or more of C1-C4alkyl, phenyl and substituted phenyl; more further specifically, each of the substituents is independently selected from one or more of C1-C2alkyl, phenyl and substituted phenyl; more further specifically, each of the substituents is independently selected from one or more of methyl, t-butyl, phenyl, tolyl, xylyl and t-butylphenyl.

[0083] Further specifically, each of L4to L6is independently selected from substituted or unsubstituted phenyl, substituted or unsubstituted C10-C14fused ring aryl; each of the substituents in the substituted phenyl and substituted C10-C14fused ring aryl is independently selected from one or more of C1-C10alkyl, phenyl and substituted phenyl; specifically, each of the substituents is independently selected from one or more of C1-C6alkyl, phenyl and substituted phenyl; further specifically, each of the substituents is independently selected from one or more of C1-C4alkyl, phenyl and substituted phenyl; more further specifically, each of the substituents is independently selected from one or more of C1-C2alkyl, phenyl and substituted phenyl; more further specifically, each of the substituents is independently selected from one or more of methyl, t-butyl, phenyl, tolyl, xylyl and t-butylphenyl.

[0084] More further specifically, each of L4to L6is independently selected from substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl; each of the substituents in the substituted phenyl and substituted naphthyl is independently selected from one or more of C1-C10alkyl, phenyl and substituted phenyl; specifically, each of the substituents is independently selected from one or more of C1-C6alkyl, phenyl and substituted phenyl; further specifically, each of the substituents is independently selected from one or more of C1-C4alkyl, phenyl and substituted phenyl; more further specifically, each of the substituents is independently selected from one or more of C1-C2alkyl, phenyl and substituted phenyl; more further specifically, each of the substituents is independently selected from one or more of methyl, t-butyl, phenyl, tolyl, xylyl and t-butylphenyl.

[0085] The R4 to R6 are each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted condensed ring group, a substituted or unsubstituted C5 to C30 spirocyclic group, a substituted or unsubstituted tetraphenylsilyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups by a single bond, and at least one is not a substituted or unsubstituted phenyl group; or any two of the R4 to R6 are connected by a single bond; the condensed ring group is formed by condensing at least two of a monocyclic aromatic group, a monocyclic alicyclic hydrocarbon group and a monocyclic heterocyclic group; when any two of the R4 to R6 are connected by a single bond, the number of the corresponding connecting groups is 0; the substituted phenyl group, the substituted condensed ring group, the substituted The substituents in the substituted diphenylamino group, the substituted C5-C30 spirocyclic group, the substituted tetraphenylsilyl group and the substituted tetraphenylmethane group are each independently selected from one or more of C1-C10 alkyl groups, phenyl groups and substituted phenyl groups; specifically, they are each independently selected from one or more of C1-C6 alkyl groups, phenyl groups and substituted phenyl groups; further specifically, they are each independently selected from one or more of C1-C4 alkyl groups, phenyl groups and substituted phenyl groups; further specifically, they are each independently selected from one or more of C1-C2 alkyl groups, phenyl groups and substituted phenyl groups; further specifically, they are each independently selected from one or more of methyl groups, tert-butyl groups, phenyl groups, tolyl groups, xylyl groups and tert-butylphenyl groups.

[0086] In a specific embodiment provided by the present invention, the fused ring group is the same as described above and will not be repeated here.

[0087] In a specific embodiment provided by the present invention, specifically, the R4 to R6 are each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fused ring group, a substituted or unsubstituted C5 to C20 spirocyclic group, a substituted or unsubstituted tetraphenylsilyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by a single bond connection of the above groups, and at least one is not a substituted or unsubstituted phenyl group; or any two of the R4 to R6 are connected to the N atom by a single bond to form a nitrogen-containing heterocycle; the substituted phenyl group, the substituted fused ring group, the substituted diphenylamino group, the substituted C5 to C20 spirocyclic group The substituents in the substituted tetraphenylsilyl group and the substituted tetraphenylmethane group are each independently selected from one or more of C1-C10 alkyl groups, phenyl groups and substituted phenyl groups; specifically, they are each independently selected from one or more of C1-C6 alkyl groups, phenyl groups and substituted phenyl groups; further specifically, they are each independently selected from one or more of C1-C4 alkyl groups, phenyl groups and substituted phenyl groups; further specifically, they are each independently selected from one or more of C1-C2 alkyl groups, phenyl groups and substituted phenyl groups; further specifically, they are each independently selected from one or more of methyl groups, tert-butyl groups, phenyl groups, tolyl groups, xylyl groups and tert-butylphenyl groups.

[0088] More specifically, the R4 to R6 are each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fused ring group, a substituted or unsubstituted spirobifluorenyl group, a substituted or unsubstituted tetraphenylsilyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups by a single bond, and at least one is not a substituted or unsubstituted phenyl group; or any two of the R4 to R6 are connected to the N atom by a single bond to form a nitrogen-containing heterocycle; the substituted phenyl group, the substituted diphenylamino group, the substituted fused ring group, the substituted spirobifluorenyl group, the substituted tetraphenylsilyl group and the substituted The substituents in the tetraphenylmethane group are each independently selected from one or more of a C1-C10 alkyl group, a phenyl group, and a substituted phenyl group; specifically, they are each independently selected from one or more of a C1-C6 alkyl group, a phenyl group, and a substituted phenyl group; further specifically, they are each independently selected from one or more of a C1-C4 alkyl group, a phenyl group, and a substituted phenyl group; further specifically, they are each independently selected from one or more of a C1-C2 alkyl group, a phenyl group, and a substituted phenyl group; further specifically, they are each independently selected from one or more of a methyl group, a tert-butyl group, a phenyl group, a tolyl group, a xylyl group, and a tert-butylphenyl group.

[0089] More specifically, the R4 to R6 are each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted dibenzopyrrolyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophenyl group, a seven-ring fused ring group, a substituted or unsubstituted spirobifluorenyl group, a substituted or unsubstituted tetraphenylsilanyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups by a single bond, and at least one is not a substituted or unsubstituted phenyl group; or any two of the R4 to R5 are connected to the N atom by a single bond to form a nitrogen-containing five-membered heterocycle; when any two of the R4 to R6 are connected by a single bond, the number of the corresponding connecting groups is 0; the substituted phenyl group, the substituted diphenylamino group, the substituted fluorenyl group, the substituted dibenzopyrrolyl group, the substituted dibenzofuranyl group, the substituted The substituents in the dibenzothiophenyl group, the substituted spirobifluorenyl group, the substituted tetraphenylsilyl group and the substituted tetraphenylmethane group are each independently selected from one or more of a C1-C10 alkyl group, a C5-C20 alicyclic hydrocarbon group, a phenyl group and a substituted phenyl group; specifically, they are each independently selected from one or more of a C1-C6 alkyl group, a C5-C15 alicyclic hydrocarbon group, a phenyl group and a substituted phenyl group; further specifically, they are each independently selected from one or more of a C1-C4 alkyl group, a C6-C10 alicyclic hydrocarbon group, a phenyl group and a substituted phenyl group; further specifically, they are each independently selected from one or more of a C1-C2 alkyl group, a C6-C10 alicyclic hydrocarbon group, a phenyl group and a substituted phenyl group; further specifically, they are each independently selected from one or more of a methyl group, a tert-butyl group, a cyclohexyl group, adamantyl group, a phenyl group, a tolyl group, a xylyl group and a tert-butylphenyl group. The seven-ring fused ring group is specifically formed by condensing any two of a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted dibenzopyrrolyl group, a substituted or unsubstituted dibenzofuranyl group and a substituted or unsubstituted dibenzothienyl group through a monocyclic heterocyclic group; the heteroatom in the monocyclic heterocyclic group is selected from one or more of N, O, S and Si.

[0090] In a specific embodiment provided by the present invention, any two of R4 to R6 are connected to the N atom through a single bond to form a nitrogen-containing five-membered heterocyclic ring; that is, the two carbon atoms of any substituent in R4 to R6, the two carbon atoms in any other two substituents and the central N atom form a nitrogen-containing five-membered heterocyclic ring, such as the two carbon atoms in R4, the two carbon atoms in R6 and the central N atom form a nitrogen-containing five-membered heterocyclic ring.

[0091] In a specific embodiment provided by the present invention, the hole transport layer in contact with the leakage current regulation layer in the A light-emitting units includes one or more compounds represented by HT-1 to HT-44:

[0092]

[0093]

[0094] In a specific embodiment provided by the present invention, when there are multiple hole transport layers in contact with the leakage control layer in the A light-emitting units, their compositions can be the same or different without any special restrictions; their thicknesses can be the same or different without any special restrictions.

[0095] In a specific embodiment provided by the present invention, the hole transport layer in the A light-emitting units that is not in contact with the leakage control layer can be selected from hole transport layer materials commonly used in the art, without special restrictions, including but not limited to N-phenylcarbazole, polyvinylcarbazole, 4,4-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (α-NPD), N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1-biphenyl]-4,4′-diamine (TPD), 4,4′,4″-tris(carbazol-9-yl)triphenylamine (TCTA), 1,1-bis[4-[N,N-di-p-toluylamino]phenyl]cyclohexane (TAPC), etc.

[0096] In a specific embodiment provided by the present invention, when there are multiple hole transport layers in the A light-emitting units that are not in contact with the leakage control layer, their compositions can be the same or different without any special restrictions; their thicknesses can be the same or different without any special restrictions.

[0097] In a specific embodiment provided by the present invention, the thickness of the hole transport layer is specifically 10 to 60 nm; optionally, the thickness of the hole transport layer is 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm or a range between any two of the above values.

[0098] In a specific embodiment provided by the present invention, the light-emitting layer can be a light-emitting layer well known to those skilled in the art, without any special restrictions, and specifically includes a host material and a doping material; the mass ratio of the host material to the doping material can be (90-99): (1-10); optionally, the mass ratio of the host material to the doping material is 90:10, 91:9, 92:8, 93:7, 94:6, 95:5, 96:4, 97:3, 98:2, 99:1 or a range between any two of the above ratios; the host material can be a host material well known to those skilled in the art, without any special restrictions, including but not limited to 9-(2-naphthyl)-10-[4-(1-naphthyl)phenyl]anthracene, 3-tert-butyl-9,10-di(2-naphthyl)anthracene (TBADN), 4,4',4"-tris(carbazol-9-yl)triphenylamine (TCTA), 4,4'-di (9-carbazole) biphenyl (CBP), poly (n-vinylcarbazole) (PVK), 9,10-di(naphthalene-2-yl)anthracene (ADN), distyryl aromaticene (DSA), bis(2-(2-hydroxyphenyl)benzothiazole) zinc (Zn(BTZ)2), etc.; the doping material includes a red light-emitting dopant, a blue light-emitting dopant or a green light-emitting dopant; the red light-emitting dopant includes but is not limited to PtOEP, Ir(piq)3, Btp2Ir(acac), etc.; the blue light-emitting agent includes but is not limited to 4,4′-bis(4-diphenylaminostyryl) biphenyl (DPAVBi), 2,5,8,11-tetra-tert-butylperylene (TBPe), compound E (structural formula shown below), etc.; the green light-emitting dopant includes but is not limited to Ir(ppy)3, Ir(ppy)2(acac), Ir(mppy)3, etc.

[0099]

[0100] In a specific embodiment provided by the present invention, the thickness of the light-emitting layer can be specifically 10 to 50 nm; optionally, the thickness of the light-emitting layer is 10 nm, 15 nm, 20 nm, 22 nm, 25 nm, 28 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm or a range between any two of the above values.

[0101] In the present invention, the composition of each light-emitting layer in the A light-emitting units may be the same or different without any special restrictions; the thickness of each light-emitting layer in the A light-emitting units may be the same or different without any special restrictions.

[0102] In an embodiment of the present application, the material of the electron transport layer is not particularly limited and can be any material commonly used in the art, including but not limited to metal-containing electron transport materials and metal-free electron transport materials. The mass ratio of the metal-containing electron transport material to the metal-free electron transport material is specifically 1:(0.1-2). Alternatively, the mass ratio of the metal-containing electron transport material to the metal-free electron transport material is 1:0.1, 1:0.3, 1:0.5, 1:0.8, 1:1, 1:1.2, 1:1.5, 1:1.8, 1:2, or any range between any two of the above ratios. The metal-containing electron transport material includes, but is not limited to, one or more of bis(10-hydroxybenzo[h]quinoline)beryllium (Bebq2), phenylpyridine beryllium (Bepp2), tris(8-hydroxyquinoline)aluminum (Alq3), tris(8-hydroxyquinoline)lithium, tris(α-naphthyl)aluminum (Almq3), bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1'-biphenyl-4-yl)aluminum (Balq), and the like. The metal-free electron transport material includes, but is not limited to, one or more of bis(2,4-dichlorophenyl)acridine (DVPBi), methylcyclopentyl ketone (MCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), compound F (structure shown below), 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBI), 2,2',2''-(benzimidazol-5-yl)-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TAZ), bis(diphenylamine)phenylcyclohexane (TAPC), 4,6-bis(3,5-di(3-pyridyl)phenyl)-2-methylpyrimidine (B3PYMPM), 1,3,5-tris[(3-pyridyl)-3-phenyl]benzene (Tmpypb), 2-(4-biphenylyl)-5-(4-tert-butyl)phenyl-1,3,4-oxadiazole (PBD), polystyrene butadiene copolymer (PPBD), 2,5-di(1-naphthyl)-1,3,4-oxadiazole (BND), polyphenylvinylene (PV), polyether ketone (OXD), and the like.

[0103]

[0104] In an embodiment of the present application, the thickness of the electron transport layer is specifically 10-50 nm. Alternatively, the thickness of the electron transport layer is 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, or any range between any two of the above values.

[0105] In the present application, the composition of each electron transport layer in the A light-emitting units can be the same or different, and the thickness of each electron transport layer in the A light-emitting units can be the same or different.

[0106] In a specific embodiment provided by the present invention, an electron blocking layer is further provided between the hole transport layer and the light-emitting layer of at least one of the A light-emitting units; and when the light-emitting unit provided with the electron blocking layer includes an injection enhancement layer, the leakage current regulation layer is provided between the hole transport layer and the electron blocking layer; further specifically, an electron blocking layer is further provided between the hole transport layer and the light-emitting layer of each of the A light-emitting units.

[0107] In a specific embodiment provided by the present invention, the material of the electron blocking layer can be any material of the electron blocking layer well known to those skilled in the art, and there is no special limitation. The present invention includes but is not limited to one or more of diphenyl diamine derivatives such as diphenyl naphthyl diamine (NPD), cross-structured diamine biphenyl derivatives such as 2,2',7,7'-tetrakis(diphenylamino)-9,9'-spirobifluorene (spiro-TAD), and star-shaped triphenylamine derivatives such as 4,4',4"-tris(N-carbazolyl)triphenylamine (TCTA).

[0108] In a specific embodiment provided by the present invention, the thickness of the electron blocking layer is specifically 5 to 30 nm; optionally, the thickness of the electron blocking layer is 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm or a range between any two of the above values.

[0109] In a specific embodiment provided by the present invention, the composition of each electron blocking layer in the A light-emitting units can be the same or different, without any special restrictions; the thickness of each electron blocking layer in the A light-emitting units can be the same or different, without any special restrictions.

[0110] In a specific embodiment provided by the present invention, a hole blocking layer is further provided between the light-emitting layer and the electron transport layer of at least one of the A light-emitting units; more specifically, a hole blocking layer is further provided between the light-emitting layer and the electron transport layer of each of the A light-emitting units. Figure 4 , Figure 4 This is a schematic structural diagram of a light-emitting unit containing a leakage current regulation layer in a stacked organic electroluminescent device provided by the present invention, wherein 3-1 is a hole transport layer, 3-5 is an electron blocking layer, 3-2 is a light-emitting layer, 3-6 is a hole blocking layer, 3-3 is an electron transport layer, and 3-4 is a leakage current regulation layer.

[0111] In an embodiment of the present application, the material of the hole blocking layer is a material with low HOMO energy level and high electron mobility, which is well known to those skilled in the art, and can be used as a hole blocking layer, and is not particularly limited, including but not limited to one or more of 2-(4-biphenyl)-5-(4-tert-butyl) phenyl-1, 3, 4-oxadiazole (PBD), 8-hydroxyquinoline aluminum (Alq3), 2, 5-di (1-naphthyl)-1, 3, 4-diazole (BND), 4, 7-diphenyl-1, 10-phenanthroline (Bphen), 1, 2, 4-triazole derivatives such as TAZ, N-aryl benzimidazole derivatives such as TPBi, quinoxaline derivatives such as TPQ, triazine derivatives such as 2, 4, 6-triazole-1, 3, 5-triazine, compound G (structural formula shown below).

[0112]

[0113] In an embodiment of the present application, the thickness of the hole blocking layer is specifically 3-10 nm; optionally, the thickness of the hole blocking layer is 3 nm, 5 nm, 8 nm, 10 nm or a range between any two of the above values.

[0114] In the present application, the composition of each hole blocking layer in the A light emitting units can be the same or different, and is not particularly limited; the thickness of each hole blocking layer in the A light emitting units can be the same or different, and is not particularly limited.

[0115] In the present application, a charge generation layer is provided between every two adjacent light emitting units; the number of the charge generation layers is A-1; each charge generation layer includes a N-type charge generation layer and a P-type charge generation layer stacked in the direction from the anode to the cathode.

[0116] In an embodiment of the present application, the N-type charge generation layer specifically includes a host material and a N-type doping material; the mass ratio of the host material to the N-type doping material is specifically (95-99):(5-1); optionally, the mass ratio of the host material to the N-type doping material is 95:5, 96:4, 97:3, 98:2, 99:1 or a range between any two of the above values; the host material includes one or more of phenanthroline compounds, nitrogen heterocyclic compounds, phosphine oxide compounds, pyridine and derivative compounds; specifically, the phenanthroline compound is compound H (structural formula shown below); the N-type doping material includes one or more of metal Li, Yb, Ag and Mg.

[0117]

[0118] In a specific embodiment provided by the present application, the thickness of the N-type charge generation layer is specifically 3-30 nm; preferably, the thickness of the N-type charge generation layer is 3 nm, 5 nm, 8 nm, 10 nm, 12 nm, 15 nm, 18 nm, 20 nm, 22 nm, 25 nm, 28 nm, 30 nm or a range between any two of the above values.

[0119] In the present application, the number of the N-type charge generation layers is more than or equal to 2; the composition of each N-type charge generation layer can be the same or different, and there is no special limitation; the thickness of each N-type charge generation layer can be the same or different, and there is no special limitation.

[0120] In a specific embodiment provided by the present application, the P-type charge generation layer comprises a compound represented by formula (I) and a P-type doping material; the mass ratio of the compound represented by formula (I) to the P-type doping material in the P-type charge generation layer is specifically (85-97):(15-3); optionally, the mass ratio of the compound represented by formula (I) to the P-type doping material is 85:15, 90:10, 95:5, 96:4, 97:3 or a range between any two of the above ratios; the P-type doping material can be any P-type doping material known to those skilled in the art, and there is no special limitation, including but not limited to one or more of quinone derivatives, hexaazatriphenylene derivatives and cyclopropane derivatives, and including one or more of cyano, fluorine, chlorine and trifluoromethyl substituents.

[0121] In a specific embodiment provided by the present application, the quinone derivative includes but is not limited to one or more of 7,7,8,8-tetracyano-p-quinodimethane and / or the following compounds:

[0122]

[0123]

[0124] In a specific embodiment provided by the present application, the hexaazatriphenylene derivative includes but is not limited to one or more of the following compounds:

[0125]

[0126] In a specific embodiment provided by the present application, the cyclopropane derivative includes but is not limited to one or more of 4,4',4"-((1E,1'E,1"E)-cyclopropane-1,2,3-trimethylenyl)tris(cyanformyl)tris(2,3,5,6-tetrafluorobenzyl) and / or the following compounds:

[0127]

[0128] In a specific embodiment provided by the present invention, the metal oxide includes but is not limited to tungsten oxide and / or molybdenum oxide.

[0129] In a specific embodiment provided by the present invention, the thickness of the P-type charge generation layer is specifically 3 to 30 nm; preferably, the thickness of the P-type charge generation layer is 3 nm, 5 nm, 8 nm, 10 nm, 12 nm, 15 nm, 18 nm, 20 nm, 22 nm, 25 nm, 28 nm, 30 nm or a range between any two of the above values.

[0130] In the present invention, as described above, the number of P-type charge generation layers is multiple (greater than or equal to 2); the composition of each P-type charge generation layer can be the same or different, and there is no special restriction; the thickness of each P-type charge generation layer can be the same or different, and there is no special restriction.

[0131] In the present invention, a hole injection layer is provided between the A light-emitting units and the anode.

[0132] In a specific embodiment provided by the present invention, the hole injection layer includes a hole transport material and a P-type dopant material; the mass ratio of the hole transport material to the P-type dopant material is (90-99): (10-1); optionally, the mass ratio of the hole transport material to the P-type dopant material is 90:10, 92:8, 93:7, 94:6, 95:5, 96:4, 97:3, 98:2, 99:1 or a range between any two of the above ratios; the hole transport material can be a hole transport material well known to those skilled in the art. , without special restrictions, including but not limited to N-phenylcarbazole, polyvinylcarbazole, 4,4-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (α-NPD), N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1-biphenyl]-4,4′-diamine (TPD), 4,4′,4″-tris(carbazol-9-yl)triphenylamine (TCTA), 1,1-bis[4-[N,N-di-p-toluylamino]phenyl]cyclohexane (TAPC), etc.; the P-type doping material is the same as described above and will not be repeated here.

[0133] In another specific embodiment provided by the present invention, the hole injection layer includes a compound represented by formula (I) and a P-type dopant material; the mass ratio of the compound represented by formula (I) to the P-type dopant material in the hole injection layer is specifically (90-99): (10-1); optionally, the mass ratio of the compound represented by formula (I) to the P-type dopant material is 90:10, 92:8, 93:7, 94:6, 95:5, 96:4, 97:3, 98:2, 99:1 or a range between any two of the above ratios; the P-type dopant material is the same as described above and will not be repeated here.

[0134] In the present invention, the specific types of the compound represented by formula (I) in the hole injection layer and the compound represented by formula (I) in the leakage current regulation layer may be the same or different, and there is no particular limitation.

[0135] In a specific embodiment provided by the present invention, the thickness of the hole injection layer is specifically 3 to 30 nm; optionally, the thickness of the hole injection layer is 3 nm, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm or a range between any two of the above values.

[0136] In a specific embodiment provided by the present invention, the material of the anode can be selected from one or more of metals, metal oxides, and conductive polymers; the metals include, but are not limited to, copper, gold, silver, iron, chromium, nickel, manganese, palladium, platinum, and alloys thereof; the metal oxides include, but are not limited to, indium oxide, zinc oxide, indium tin oxide (ITO), indium zinc oxide (IZO), and the like; and the conductive polymers include, but are not limited to, polyaniline, polypyrrole, and poly(3-methylthiophene). Furthermore, the material of the anode can also be selected from materials other than the materials listed above that facilitate hole injection, and combinations thereof, including known materials suitable for anodes.

[0137] In the present invention, an electron injection layer is provided between the A light-emitting units and the cathode; the electron injection layer can be any electron injection layer well known to those skilled in the art, and there is no special limitation. Specifically, the electron injection layer includes but is not limited to one or more of metallic lithium, lithium fluoride, 8-hydroxyquinoline lithium, metallic ytterbium, Ag and other metals; the thickness of the electron injection layer is specifically 0.1 to 10 nm; optionally, the thickness of the electron injection layer is 0.1 nm, 0.5 nm, 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 10 nm or a range between any two of the above values.

[0138] In a specific embodiment provided by the present invention, the cathode includes a metal material; the metal material includes but is not limited to one or more of Mg, Ag, Al, and Li; the thickness of the cathode is specifically 10 to 400 nm; optionally, the thickness of the cathode is 10 nm, 14 nm, 20 nm, 30 nm, 50 nm, 100 nm, 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm or a range between any two of the above values.

[0139] In a specific embodiment provided by the present invention, a covering layer is further provided on the surface of the cathode away from the light emitting unit; see Figure 5 , Figure 5 Schematic diagram of the structure of the stacked organic electroluminescent device provided by the present invention, wherein 1 is a cathode, 2 is an electron injection layer, 3 is a light-emitting unit, 4 is a P-type charge generation layer, 5 is an N-type charge generation layer, 6 is a light-emitting unit, 7 is a hole injection layer, 8 is an anode, and 9 is a covering layer; the material of the covering layer includes but is not limited to at least one of triarylamine compounds, cyclic urea compounds, acyl structure compounds, dibenzothiophene compounds, dibenzofuran compounds, and carbazole compounds; in the embodiments provided by the present invention, compound K (structure shown below) is specifically used as an example for illustration; the thickness of the covering layer is specifically 10 to 150 nm; optionally, the thickness of the covering layer is 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, 140 nm, 150 nm, or a range between any two of the above values.

[0140] In the present invention, the stacked organic electroluminescent device can be prepared according to methods well known to those skilled in the art, specifically: forming an anode on a transparent or opaque smooth substrate, forming an organic thin layer on the anode, and forming a cathode on the organic thin layer. The organic thin layer includes the above-mentioned hole injection layer, A light-emitting units, a charge generation layer, and an electron injection layer; the formation of the organic thin layer can adopt known film-forming methods such as evaporation, sputtering, spin coating, dipping, ion plating, etc. Finally, a covering layer (CPL layer) is prepared on the cathode. The CPL layer can be prepared by evaporation or solution processing. Solution processing methods include inkjet printing, spin coating, doctor blade coating, screen printing, roll-to-roll printing, and the like.

[0141] The compound shown in formula (I) has anisotropy and / or a low refractive index and / or contains a functional group with large steric hindrance, which gives it a good hole injection effect and a slow lateral mobility. The present invention uses the compound shown in formula (I) as the main material of the P-type charge generation layer, which has a good hole injection effect and slow lateral mobility, to reduce the lateral leakage of the charge generation layer; at the same time, by arranging a leakage control layer containing the compound shown in formula (I) between the hole transport layer and the light-emitting layer of the light-emitting unit, it plays a role in reducing leakage and balancing carriers, not only reducing the lateral leakage of the stacked organic electroluminescent device and improving the low grayscale visual effect, but also improving the overall efficiency of the device; and the stacked organic electroluminescent device has mass production conditions and can achieve large-scale production. Further, the present invention uses the compound shown in formula (II) to prepare a hole transport layer in contact with the leakage control layer, which has fast injection and fast transport characteristics, and can further reduce the device voltage. Further, the present invention uses the compound shown in formula (I) as the main material of the hole injection layer, which can further reduce the lateral leakage of the device and improve the device efficiency.

[0142] The present invention also provides a display panel comprising the above-mentioned laminated organic electroluminescent device.

[0143] The present invention also provides a display device comprising the above-mentioned display panel.

[0144] To further illustrate the present invention, a stacked organic electroluminescent device, a display panel, and a display apparatus provided by the present invention are described in detail below with reference to embodiments.

[0145] The reagents used in the following examples are all commercially available.

[0146] Example 1

[0147] See also Figure 6 , Figure 6 The schematic structural diagram of the stacked organic electroluminescent device provided in Example 1 includes the following structures arranged in sequence from bottom to top: an anode (Anode), a hole injection layer HIL, a first hole transport layer HTL1, a first electron blocking layer EBL1, a first light-emitting layer EML1, a first hole blocking layer HBL1, a first electron transport layer ETL1, an N-type charge generation layer NCGL, a P-type charge generation layer PCGL, a second hole transport layer HTL2, a leakage control layer LHT, a second electron blocking layer EBL2, a second light-emitting layer EML2, a second hole blocking layer HBL2, a second electron transport layer ETL2, an electron injection layer EIL, a cathode (Cathode) and a covering layer CPL.

[0148] This embodiment provides a stacked OLED, and the specific preparation steps include:

[0149] Step (1), cutting a glass substrate into a size of 50 mm × 50 mm × 0.7 mm, ultrasonically treating in isopropyl alcohol and deionized water for 30 minutes, respectively, and then exposing to ozone for cleaning for 10 minutes; mounting the glass substrate with an ITO anode obtained by magnetron sputtering on a vacuum deposition device;

[0150] Step (2): prepare the hole injection layer at a vacuum degree of 2×10 -6 Pa, vacuum evaporation of compound A and compound B on the ITO anode layer, wherein compound B is used as the main material, compound A is used as the doping material, the mass ratio of compound B to compound A is 97:3, and the thickness is 10 nm, as a hole injection layer;

[0151] Step (3), preparing a first hole transport layer, vacuum evaporating compound B on the hole injection layer as the first hole transport layer, with a thickness of 25 nm;

[0152] Step (4), preparing a first electron blocking layer, vacuum evaporating compound C on the hole injection layer as the first electron blocking layer, with a thickness of 10 nm;

[0153] Step (5), preparing a first light-emitting layer, vacuum evaporating the first light-emitting layer on the first electron blocking layer, using organic compound D as the host material and compound E as the doping material, the mass ratio of compound D to compound E is 98:2, and the thickness of the first light-emitting layer is 22 nm;

[0154] Step (6), preparing a first hole blocking layer, vacuum evaporating compound G on the first light-emitting layer as the first hole blocking layer, with a thickness of 8 nm;

[0155] Step (7), preparing a first electron transport layer, vacuum evaporating compounds F and I on the first hole blocking layer as the first electron transport layer, the mass ratio of compounds F and I being 1:1, and the thickness being 15 nm;

[0156] Step (8), preparing an N-type charge generation layer, vacuum evaporating compounds H and Yb on the first electron transport layer as the N-type charge generation layer, the mass ratio of compound H to Yb is 97:3, and the thickness is 12 nm;

[0157] Step (9), preparing a P-type charge generation layer, vacuum evaporating compound A and compound LHT-5 on the N-type charge generation layer as a P-type charge generation layer, wherein compound LHT-5 is used as a host material, compound A is used as a dopant material, the mass ratio of compound LHT-5 to compound A is 95:5, and the thickness is 10 nm;

[0158] Step (10), preparing a second hole transport layer, vacuum evaporating compound B on the P-type charge generation layer as the second hole transport layer, with a thickness of 50 nm;

[0159] Step (11), preparing a leakage current regulating layer, vacuum evaporating compound LHT-5 on the second hole transport layer as a leakage current regulating layer with a thickness of 10 nm;

[0160] Step (12), preparing a second electron blocking layer, vacuum evaporating compound C on the leakage current regulating layer as the second electron blocking layer, with a thickness of 10 nm;

[0161] Step (13), preparing a second light-emitting layer, vacuum evaporating the second light-emitting layer on the second electron blocking layer, using organic compound D as the host material and compound E as the doping material, the mass ratio of compound D to compound E is 98:2, and the thickness of the second light-emitting layer is 22 nm;

[0162] Step (14), preparing a second hole blocking layer, vacuum evaporating compound G on the second light-emitting layer as the second hole blocking layer, with a thickness of 5 nm;

[0163] Step (15), preparing a second electron transport layer, vacuum evaporating compounds F and I on the second hole blocking layer as the second electron transport layer, the mass ratio of compound F to compound I is 1:1, and the thickness is 35 nm;

[0164] Step (16), preparing an electron injection layer, vacuum evaporating Yb as an electron injection layer on the second electron transport layer, with a thickness of 1 nm;

[0165] Step (17), preparing a cathode, vacuum evaporating a magnesium-silver electrode on the electron injection layer as the cathode, with a mass ratio of Mg to Ag of 1:9 and a thickness of 14 nm;

[0166] Step (18), preparing a covering layer, vacuum evaporating compound K on the cathode with a thickness of 60 nm as a covering layer, and obtaining the Tandem OLED device.

[0167] Example 2

[0168] In step (9), compound LHT-5 is replaced by LHT-6; in step (11), compound LHT-5 is replaced by LHT-6; the other steps are the same as in Example 1.

[0169] Example 3

[0170] In step (9), compound LHT-5 is replaced by LHT-11; in step (11), compound LHT-5 is replaced by LHT-11; the other steps are the same as in Example 1.

[0171] Example 4

[0172] In step (9), compound LHT-5 is replaced by LHT-21; in step (11), compound LHT-5 is replaced by LHT-21; the other steps are the same as in Example 1.

[0173] Example 5

[0174] In step (9), compound LHT-5 is replaced by LHT-69; in step (11), compound LHT-5 is replaced by LHT-69; the other steps are the same as in Example 1.

[0175] Example 6

[0176] In step (9), compound LHT-5 is replaced by LHT-70; in step (11), compound LHT-5 is replaced by LHT-70; the other steps are the same as in Example 1.

[0177] Example 7

[0178] In step (9), compound LHT-5 is replaced by LHT-75; in step (11), compound LHT-5 is replaced by LHT-75; the other steps are the same as in Example 1.

[0179] Example 8

[0180] In step (9), compound LHT-5 is replaced by LHT-32; in step (11), compound LHT-5 is replaced by LHT-32; the other steps are the same as in Example 1.

[0181] Example 9

[0182] In step (10), compound B was replaced by LH-29, and the other steps were the same as in Example 1.

[0183] Example 10

[0184] In step (9), compound LHT-5 is replaced by LHT-6;

[0185] In step (10), compound B is replaced by LH-36;

[0186] In step (11), compound LHT-5 is replaced by LHT-6; other steps are the same as in Example 1.

[0187] Example 11

[0188] In step (9), compound LHT-5 is replaced by LHT-21;

[0189] In step (10), compound B is replaced with LH-28;

[0190] In step (11), compound LHT-5 was replaced by LHT-21; the other steps were the same as in Example 1.

[0191] Example 12

[0192] In step (9), compound LHT-5 is replaced by LHT-30;

[0193] In step (10), compound B is replaced by LH-18;

[0194] In step (11), compound LHT-5 was replaced by LHT-30; the other steps were the same as in Example 1.

[0195] Example 13

[0196] See also Figure 7 , Figure 7 A schematic structural diagram of a stacked organic electroluminescent device provided in Example 13 includes the following structures arranged in sequence from bottom to top: an anode, a hole injection layer HIL, a first hole transport layer HTL1, a first leakage regulation layer LHT1, a first electron blocking layer EBL1, a first light-emitting layer EML1, a first hole blocking layer HBL1, a first electron transport layer ETL1, an N-type charge generation layer NCGL, a P-type charge generation layer PCGL, a second hole transport layer HTL2, a second leakage regulation layer LHT2, a second electron blocking layer EBL2, a second light-emitting layer EML2, a second hole blocking layer HBL2, a second electron transport layer ETL2, an electron injection layer EIL, a cathode, and a covering layer CPL.

[0197] This embodiment provides a stacked OLED, and the specific preparation steps include:

[0198] Step (1), cutting a glass substrate into a size of 50 mm × 50 mm × 0.7 mm, ultrasonically treating in isopropyl alcohol and deionized water for 30 minutes, respectively, and then exposing to ozone for cleaning for 10 minutes; mounting the glass substrate with an ITO anode obtained by magnetron sputtering on a vacuum deposition device;

[0199] Step (2): prepare the hole injection layer at a vacuum degree of 2×10 -6 Under Pa, compound A and compound LHT-5 were vacuum evaporated on the ITO anode layer, wherein compound LHT-5 was used as the main material, compound A was used as the doping material, the mass ratio of compound LHT-5 to compound A was 97:3, and the thickness was 10 nm, as a hole injection layer;

[0200] Step (3), preparing a first hole transport layer, vacuum evaporating compound B on the hole injection layer as the first hole transport layer, with a thickness of 15 nm;

[0201] Step (4), preparing a first leakage current regulating layer LHT1, vacuum evaporating compound LHT-5 on the first hole transport layer as the first leakage current regulating layer, with a thickness of 10 nm;

[0202] Step (5), preparing a first electron blocking layer, vacuum evaporating compound C on the first leakage current regulating layer as the first electron blocking layer, with a thickness of 10 nm;

[0203] Step (6), preparing a first light-emitting layer, vacuum evaporating the first light-emitting layer on the first electron blocking layer, using organic compound D as the host material and compound E as the doping material, the mass ratio of compound D to compound E is 98:2, and the thickness of the first light-emitting layer is 22 nm;

[0204] Step (7), preparing a first hole blocking layer, vacuum evaporating compound G on the first light-emitting layer as the first hole blocking layer, with a thickness of 8 nm;

[0205] Step (8), preparing a first electron transport layer, vacuum evaporating compounds F and I on the first hole blocking layer as the first electron transport layer, the mass ratio of compounds F and I being 1:1, and the thickness being 15 nm;

[0206] Step (9), preparing an N-type charge generation layer, vacuum evaporating compounds H and Yb on the first electron transport layer as the N-type charge generation layer, the mass ratio of compound H to Yb is 97:3, and the thickness is 12 nm;

[0207] Step (10), preparing a P-type charge generation layer, vacuum evaporating compound A and compound LHT-5 on the N-type charge generation layer as a P-type charge generation layer, wherein compound LHT-5 is used as a host material, compound A is used as a doping material, the mass ratio of compound B to compound A is 95:5, and the thickness is 10 nm;

[0208] Step (11), preparing a second hole transport layer, vacuum evaporating compound B on the P-type charge generation layer as the second hole transport layer, with a thickness of 50 nm;

[0209] Step (12), preparing a second leakage current regulating layer, vacuum evaporating compound LHT-5 on the second hole transport layer as the second leakage current regulating layer, with a thickness of 10 nm;

[0210] Step (13), preparing a second electron blocking layer, vacuum evaporating compound C on the second leakage current regulating layer as the second electron blocking layer, with a thickness of 10 nm;

[0211] Step (14), preparing a second light-emitting layer, vacuum evaporating the second light-emitting layer on the second electron blocking layer, using organic compound D as the host material and compound E as the doping material, the mass ratio of compound D to compound E is 98:2, and the thickness of the second light-emitting layer is 22 nm;

[0212] Step (15), preparing a second hole blocking layer, vacuum evaporating compound G on the second light-emitting layer as the second hole blocking layer, with a thickness of 5 nm;

[0213] Step (16), preparing a second electron transport layer, vacuum evaporating compounds F and I on the second hole blocking layer as the second electron transport layer, the mass ratio of compound F to compound I is 1:1, and the thickness is 35 nm;

[0214] Step (17), preparing an electron injection layer, vacuum evaporating Yb as an electron injection layer on the second electron transport layer, with a thickness of 1 nm;

[0215] Step (18), preparing a cathode, vacuum evaporating a magnesium-silver electrode on the electron injection layer as the cathode, with a mass ratio of Mg to Ag of 1:9 and a thickness of 14 nm;

[0216] Step (19), preparing a covering layer, vacuum evaporating compound K on the cathode with a thickness of 60 nm as a covering layer, and obtaining the Tandem OLED device.

[0217] Example 14

[0218] In step (2), compound LHT-5 is replaced with LHT-40;

[0219] In step (4), compound LHT-5 is replaced with LHT-40;

[0220] In step (10), compound LHT-5 is replaced with LHT-40;

[0221] In step (12), compound LHT-5 was replaced by LHT-40, and the other steps were the same as in Example 13.

[0222] Example 15

[0223] In step (2), compound LHT-5 is replaced with LHT-79;

[0224] In step (4), compound LHT-5 is replaced with LHT-79;

[0225] In step (10), compound LHT-5 is replaced with LHT-79;

[0226] In step (12), compound LHT-5 was replaced by LHT-79, and the other steps were the same as in Example 13.

[0227] Example 16

[0228] In step (2), compound LHT-5 is replaced with LHT-84;

[0229] In step (4), compound LHT-5 is replaced with LHT-84;

[0230] In step (10), compound LHT-5 is replaced with LHT-84;

[0231] In step (12), compound LHT-5 was replaced by LHT-84, and the other steps were the same as in Example 13.

[0232] Comparative Example 1

[0233] Step (9), preparing a P-type charge generation layer, vacuum evaporating compound A and compound B on the N-type charge generation layer to form a P-type charge generation layer, wherein compound B is used as the main material and compound A is used as the dopant material, the mass ratio of compound B to compound A is 95:5, and the thickness is 10 nm;

[0234] Step (10), preparing a second hole transport layer, vacuum evaporating compound B on the P-type charge generation layer as the second hole transport layer, with a thickness of 60 nm;

[0235] Step (11) was not performed, and the other steps were the same as those in Example 1.

[0236] Comparative Example 2

[0237] Step (9), preparing a P-type charge generation layer, vacuum evaporating compound A and compound B on the N-type charge generation layer to form a P-type charge generation layer, wherein compound B is used as the main material and compound A is used as the dopant material, the mass ratio of compound B to compound A is 95:5, and the thickness is 10 nm;

[0238] Step (10), preparing a second hole transport layer, vacuum evaporating compound B on the P-type charge generation layer as the second hole transport layer, with a thickness of 50 nm;

[0239] In step (11), LHT-5 is replaced by compound HT-40 in formula (II); other steps are the same as those in Example 1.

[0240]

[0241] Device performance testing

[0242] 1) Working voltage and current efficiency test: The stacked organic light-emitting devices prepared in the examples and comparative examples were tested for current at different voltages using a Keithley 2365A digital nanovoltmeter. The current was then divided by the luminous area to obtain the current density of the device at different voltages. The brightness and radiant energy flux density of the device at different voltages were tested using a Konicaminolta CS-2000 spectroradiometer. Based on the current density and brightness of the device at different voltages, the current density at the same current density (10 mA / cm 2 )’s operating voltage V and current efficiency BI (Cd / A / CIEy).

[0243] The working voltage detected in Comparative Example 1 is recorded as 100%. The working voltage value of the embodiment or comparative example = the working voltage of the embodiment / the working voltage of Comparative Example 1 × 100%.

[0244] The current efficiency of the comparative example 1 was taken as 100%. The current efficiency of the example or comparative example = the current efficiency of the example or comparative example / the current efficiency of the comparative example 1 × 100%.

[0245] A lower operating voltage means the device requires less power to operate under the same conditions. This reduces power consumption, improves energy efficiency, and extends battery life.

[0246] Current efficiency refers to the amount of light or other effective output a device can produce at a given current input. High current efficiency means that the device can output more light or have higher performance at the same input current.

[0247] 2) Test of lateral leakage current: The glass substrate of the laminated electro-organic light emitting device of the above embodiment or comparative example is replaced with a substrate having Figure 8 structure( Figure 8 The substrate is prepared on a substrate having a structure diagram of a substrate selected for leakage current testing provided in some embodiments of the present application, and the local morphology of the substrate is referenced Figure 8 The pattern-filled area is the vapor deposition area 700 where each stacked electroluminescent organic light-emitting device is vapor-deposited. This vapor deposition area 700 is a solid portion; the white-filled area is the hollowed-out area 800 of the substrate body. After the device is prepared, a voltage of -10V to +10V is applied across the two electrodes (anode and cathode). A Keithley 2365A digital nanovoltmeter is used to measure the current of the devices of the embodiment and comparative example at different voltages. The leakage current of comparative example 1 at 10V is recorded as 100%. The leakage current value of the embodiment or comparative example (the relative leakage current value under the same conditions) = leakage current of the embodiment or comparative example / leakage current of comparative example 1 × 100%.

[0248] The device performance test results are shown in Table 1.

[0249] Table 1: Device performance results of various embodiments and comparative examples

[0250]

[0251] As can be seen from Table 1, the leakage current of the stacked organic electroluminescent device provided by the present application is significantly reduced, which can improve the low grayscale efficiency. It also has a lower operating voltage and higher current efficiency.

[0252] The various embodiments in this specification are described in a progressive, parallel, or combined manner. Each embodiment focuses on the differences from other embodiments, and reference can be made to the common and similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For relevant parts, refer to the description of the methods.

[0253] It should be noted that in the description of this application, it should be understood that the description of the drawings and embodiments is illustrative rather than restrictive. The same figure numbers throughout the embodiments of the specification identify the same structure. In addition, for the purpose of understanding and ease of description, the drawings may exaggerate the thickness of some layers, films, panels, regions, etc. It is also understood that when an element such as a layer, film, region or substrate is referred to as "on" another element, the element may be directly on the other element or there may be an intermediate element. In addition, "on" refers to positioning an element on or below another element, but does not essentially mean positioning on the upper side of another element according to the direction of gravity.

[0254] The terms "upper," "lower," "top," "bottom," "inner," "outer," and the like, indicating positions or locations, are based on the positions or locations shown in the accompanying drawings and are intended solely to facilitate and simplify the description of this application. They are not intended to indicate or imply that the devices or elements referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. When a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a centrally located component.

[0255] It should also be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such article or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the article or device comprising the aforementioned elements.

[0256] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A stacked organic electroluminescent device, characterized in that: include: anode; cathode; A light-emitting units stacked between the anode and the cathode; A is an integer greater than or equal to 2; a hole injection layer disposed between the anode and a light-emitting unit adjacent to the anode among the A light-emitting units; an electron injection layer disposed between the cathode and a light-emitting unit adjacent to the cathode among the A light-emitting units; a charge generation layer disposed between every two adjacent light-emitting units among the A light-emitting units; Each charge generation layer includes an N-type charge generation layer and a P-type charge generation layer stacked in sequence from the anode to the cathode; The P-type charge generation layer comprises a compound represented by formula (I) and a P-type dopant material; Each light-emitting unit includes a hole transport layer, a light-emitting layer, and an electron transport layer stacked in sequence from the anode to the cathode; and a leakage current regulating layer is provided between the hole transport layer and the light-emitting layer of at least one light-emitting unit among the A light-emitting units; The leakage regulating layer includes a compound represented by formula (I): wherein n1, m1 and p1 are each independently selected from integers ranging from 0 to 3; The L1 to L3 are linking groups, each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted C10 to C30 fused ring aromatic group; Each of R1 to R3 is independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fused ring group, a substituted or unsubstituted C5-C30 spirocyclic group, a substituted or unsubstituted tetraphenylsilyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups via a single bond, and at least one of the above groups is not a substituted or unsubstituted phenyl group; or any two of R1 to R3 are connected by a single bond; the fused ring group is formed by condensing at least two of a monocyclic aromatic group, a monocyclic alicyclic hydrocarbon group, and a monocyclic heterocyclic group; When any two of R1 to R3 are connected by a single bond, the number of the corresponding connecting groups is 0; The substituents in the substituted phenyl group, substituted C10-C30 fused ring aromatic group, substituted fused ring group, substituted diphenylamino group, substituted C5-C30 spirocyclic group, substituted tetraphenylsilyl group and substituted tetraphenylmethane group in formula (I) are each independently selected from one or more of halogen, C1-C10 alkyl group, C1-C10 fluoroalkyl group, C5-C20 alicyclic hydrocarbon group, phenyl group and substituted phenyl group.

2. The stacked organic electroluminescent device according to claim 1, characterized in that: The L1-L3 are each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group; the R1-R3 are each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fused ring group, a substituted or unsubstituted spirobifluorenyl group, a substituted or unsubstituted tetraphenylsilyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups via a single bond, and at least one is not a substituted or unsubstituted phenyl group; or any two of the R1-R3 are connected to the nitrogen atom via a single bond to form a nitrogen-containing heterocyclic ring; the number of monocyclic rings in the fused ring group is an integer of 2 to 10; The monocyclic aromatic group is selected from a six-membered monocyclic aromatic group; the monocyclic aliphatic group is selected from one or more of a three-membered monocyclic aliphatic group, a four-membered monocyclic aliphatic group, a five-membered monocyclic aliphatic group and a six-membered monocyclic aliphatic group; the monocyclic heterocyclic group is selected from one or more of a three-membered monocyclic heterocyclic group, a four-membered monocyclic heterocyclic group, a five-membered monocyclic heterocyclic group and a six-membered monocyclic heterocyclic group; The substituents in the substituted phenyl, substituted naphthyl, substituted diphenylamino, substituted fused ring, substituted spirobifluorenyl, substituted tetraphenylsilyl and substituted tetraphenylmethane in formula (I) are independently selected from one or more of halogen, C1-C10 alkyl, C1-C10 fluoroalkyl, C5-C20 alicyclic hydrocarbon, phenyl and substituted phenyl.

3. The stacked organic electroluminescent device according to claim 2, characterized in that: The R1 to R3 are each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted dibenzopyrrolyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothienyl group, a seven-ring condensed ring group, a substituted or unsubstituted spirobifluorenyl group, a substituted or unsubstituted tetraphenylsilanyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups by a single bond, and at least one is not a substituted or unsubstituted phenyl group; or any two of the R1 to R3 are connected to the nitrogen atom by a single bond to form a nitrogen-containing five-membered heterocyclic ring; the seven-ring condensed ring group is formed by any two of a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted dibenzopyrrolyl group, a substituted or unsubstituted dibenzofuranyl group and a substituted or unsubstituted dibenzothienyl group fused together by a monocyclic heterocyclic group; The heteroatom in the monocyclic heterocyclic group is selected from one or more of N, O, S and Si; In formula (I), the substituents in the substituted phenyl, substituted naphthyl, substituted diphenylamino, substituted fluorenyl, substituted naphthyl, substituted dibenzopyrrolyl, substituted dibenzofuranyl, substituted dibenzothiophenyl, substituted spirobifluorenyl, substituted tetraphenylsilyl and substituted tetraphenylmethane are independently selected from one or more of halogen, C1-C10 alkyl, C1-C10 fluoroalkyl, C6-C10 alicyclic hydrocarbon, phenyl and substituted phenyl.

4. The stacked organic electroluminescent device according to claim 1, characterized in that: n1, m1 and p1 are each independently selected from integers of 0 to 2; The substituents in the substituted phenyl group, substituted C10-C30 fused ring aromatic group, substituted fused ring group, substituted diphenylamino group, substituted C5-C30 spirocyclic group, substituted tetraphenylsilyl group and substituted tetraphenylmethane group in formula (I) are each independently selected from one or more of fluorine, methyl, tert-butyl, fluoromethyl, cyclohexyl, adamantyl, phenyl, tolyl, xylyl, fluoromethyl, phenyl and tert-butylphenyl group.

5. The stacked organic electroluminescent device according to any one of claims 1 to 4, characterized in that: The leakage regulating layer includes one or more compounds selected from the group consisting of LHT-1 to LHT-96:

6. The stacked organic electroluminescent device according to any one of claims 1 to 5, characterized in that: The hole transport layer in contact with the leakage current regulation layer in the A light-emitting units includes a compound represented by formula (II); the HOMO energy difference between the compound represented by formula (II) and the compound represented by formula (I) is less than or equal to 0.3 eV, and the refractive index of the compound represented by formula (I) is lower than that of the hole transport layer; wherein n2, m2 and p2 are each independently selected from integers of 0 to 3; The L4 to L6 are linking groups, each independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted C10 to C30 fused ring aromatic group; The substituents in the substituted phenyl group and the substituted C10-C30 fused ring aromatic group in L4-L5 are each independently selected from one or more of a C1-C10 alkyl group, a phenyl group and a substituted phenyl group; Each of R4 to R6 is independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fused ring group, a substituted or unsubstituted C5-C30 spirocyclic group, a substituted or unsubstituted tetraphenylsilyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups via a single bond, and at least one of the above groups is not a substituted or unsubstituted phenyl group; or any two of the R4 to R6 are connected by a single bond; the fused ring group is formed by condensing at least two of a monocyclic aromatic group, a monocyclic alicyclic hydrocarbon group, and a monocyclic heterocyclic group; When any two of R4 to R6 are connected by a single bond, the number of the corresponding connecting groups is 0; The substituents in the substituted phenyl group, substituted condensed ring group, substituted diphenylamino group, substituted C5-C30 spirocyclic group, substituted tetraphenylsilyl group and substituted tetraphenylmethane group in R4-R6 are each independently selected from one or more of C1-C10 alkyl group, C5-C20 alicyclic hydrocarbon group, phenyl group and substituted phenyl group.

7. The stacked organic electroluminescent device according to claim 6, characterized in that: The L4 to L6 are each independently selected from substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl; The substituents in the substituted phenyl and substituted naphthyl groups in L1 to L3 are each independently selected from one or more of a C1 to C10 alkyl group, a phenyl group, and a substituted phenyl group; Each of R4 to R6 is independently selected from a substituted or unsubstituted phenyl group, a substituted or unsubstituted diphenylamino group, a substituted or unsubstituted fused ring group, a substituted or unsubstituted spirobifluorenyl group, a substituted or unsubstituted tetraphenylsilyl group, a substituted or unsubstituted tetraphenylmethane group, or a group formed by connecting the above groups via a single bond, and at least one of the groups is not a substituted or unsubstituted phenyl group; or any two of the R4 to R6 are connected to the nitrogen atom via a single bond to form a nitrogen-containing heterocyclic ring; the number of monocyclic rings in the fused ring group is an integer of 2 to 10; The monocyclic aromatic group in formula (II) is selected from a six-membered monocyclic aromatic group; the monocyclic aliphatic group is selected from one or more of a three-membered monocyclic aliphatic group, a four-membered monocyclic aliphatic group, a five-membered monocyclic aliphatic group and a six-membered monocyclic aliphatic group; the monocyclic heterocyclic group is selected from one or more of a three-membered monocyclic heterocyclic group, a four-membered monocyclic heterocyclic group, a five-membered monocyclic heterocyclic group and a six-membered monocyclic heterocyclic group; The substituents in the substituted phenyl group, substituted diphenylamino group, substituted condensed ring group, substituted spirobifluorenyl group, substituted tetraphenylsilyl group and substituted tetraphenylmethane group in R4 to R6 are each independently selected from one or more of C1 to C10 alkyl groups, C6 to C10 alicyclic hydrocarbon groups, phenyl groups and substituted phenyl groups.

8. The stacked organic electroluminescent device according to claim 6 or 7, characterized in that: The hole transport layer in contact with the leakage current regulating layer in the A light-emitting units includes one or more compounds selected from the group consisting of HT-1 to HT-44:

9. The stacked organic light-emitting device according to any one of claims 1 to 8, characterized in that: When the number of the leakage current regulating layers is smaller than the number of the light-emitting units, the leakage current regulating layers are arranged in the light-emitting units that are not in contact with the hole injection layer.

10. The stacked organic light emitting device according to claim 9, characterized in that: A leakage current regulating layer is provided between the hole transport layer and the light-emitting layer of A-1 light-emitting units or A light-emitting units in the A light-emitting units.

11. The stacked organic electroluminescent device according to any one of claims 1 to 10, characterized in that: The hole injection layer includes a hole transport material and a P-type dopant material; the mass ratio of the hole transport material to the P-type dopant material in the hole injection layer is (90-99): (10-1); the P-type dopant material is selected from an organic P-type dopant material and / or a metal oxide; the organic P-type dopant material is selected from one or more of a quinone derivative, a hexaazatriphenylene derivative and a cyclopropane derivative, and includes one or more substituents selected from cyano, fluorine, chlorine and trifluoromethyl.

12. The stacked organic electroluminescent device according to any one of claims 1 to 10, characterized in that: The hole injection layer includes a compound represented by formula (I) and a P-type dopant material; the mass ratio of the compound represented by formula (I) to the P-type dopant material in the hole injection layer is (90-99): (10-1); the P-type dopant material is selected from an organic P-type dopant material and / or a metal oxide; the organic P-type dopant material is selected from one or more of a quinone derivative, a hexaazatriphenylene derivative and a cyclopropane derivative, and includes one or more substituents selected from cyano, fluorine, chlorine and trifluoromethyl.

13. The stacked organic electroluminescent device according to any one of claims 1 to 12, characterized in that: The N-type charge generation layer includes a main material and an N-type dopant material; the mass ratio of the main material to the N-type dopant material is (95-99): (5-1); the main material includes one or more of phenanthroline, nitrogen heterocycle, phosphine oxide, pyridine and derivative compounds; the N-type dopant material includes one or more of metals Li, Yb, Ag and Mg; And / or, the mass ratio of the compound represented by formula (I) to the P-type doping material in the P-type charge generation layer is (85-97): (15-3); the P-type doping material is selected from organic P-type doping materials and / or metal oxides; the organic P-type doping material is selected from one or more of quinone derivatives, hexaazatriphenylene derivatives and cyclopropane derivatives, and includes one or more substituents selected from cyano, fluorine, chlorine and trifluoromethyl.

14. The stacked organic electroluminescent device according to any one of claims 11 to 13, wherein the quinone derivative is selected from 7,7,8,8-tetracyano-p-benzoquinodimethane and / or one or more of the following compounds: The hexaazatriphenylene derivative is selected from one or more of the following compounds: The cyclopropane derivative is selected from one or more of 4,4′,4″-((1E,1′E,1″E)-cyclopropane-1,2,3-trimethylenetris(cyanoformylidene))tris(2,3,5,6-tetrafluorobenzyl) and / or the following compounds: The metal oxide is selected from tungsten oxide and / or molybdenum oxide.

15. The stacked organic electroluminescent device according to any one of claims 1 to 14, characterized in that: The electron transport layer comprises a metal-containing electron transport material and a metal-free electron transport material; the mass ratio of the metal-containing electron transport material to the metal-free electron transport material is 1:(0.1-2); And / or, the electron injection layer includes one or more of metallic lithium, lithium fluoride, 8-hydroxyquinoline lithium, metallic ytterbium and Ag.

16. The stacked organic electroluminescent device according to any one of claims 1 to 15, characterized in that: An electron blocking layer is provided between the hole transport layer and the light-emitting layer of at least one of the A light-emitting units, and when the light-emitting unit provided with the electron blocking layer includes a leakage current regulation layer, the leakage current regulation layer is provided between the hole transport layer and the electron blocking layer; And / or, a hole blocking layer is provided between the light-emitting layer and the electron transport layer of at least one of the A light-emitting units.

17. The stacked organic electroluminescent device according to claim 16, characterized in that: The thickness of the electron blocking layer is 5 to 30 nm; And / or, the electron blocking layer comprises one or more of a benzyldiamine derivative, a cross-structured diamine biphenyl derivative, and a star-shaped triphenylamine derivative; and / or, the hole blocking layer has a thickness of 3 to 10 nm; And / or, the hole blocking layer includes one or more of 2-(4-biphenyl)-5-(4-tert-butyl)phenyl-1,3,4-oxadiazole, 8-hydroxyquinoline aluminum, 2,5-di(1-naphthyl)-1,3,4-oxadiazole, 4,7-diphenyl-1,10-phenanthroline, 1,2,4-triazole derivatives, N-arylbenzimidazole derivatives, quinoxaline derivatives and triazine derivatives.

18. The stacked organic electroluminescent device according to any one of claims 1 to 17, characterized in that: The thickness of the leakage current regulating layer is 3 to 30 nm.

19. The stacked organic electroluminescent device according to any one of claims 1 to 18, characterized in that: The thickness of the hole injection layer is 3 to 30 nm; The thickness of the electron injection layer is 0.1 to 10 nm; The thickness of the N-type charge generation layer and the P-type charge generation layer are independently 3 to 30 nm; The thickness of the hole transport layer of the A light-emitting units is independently 10 to 60 nm; The thickness of the light-emitting layers of the A light-emitting units is independently 10 to 50 nm; The thickness of the electron transport layer of the A light-emitting units is independently 10 to 50 nm.

20. A display panel, characterized in that: A stacked organic electroluminescent device comprising the layered organic electroluminescent device according to any one of claims 1 to 19.

21. A display device, characterized in that: Includes the display panel according to claim 20.

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