Display panel and display device

Abstract

The invention provides a display panel and a display device. The absolute value of the highest occupied molecular orbital energy level of a green light main body material in the green light emitting unit is increased, and / or the hole mobility of the green light main body material in the green light emitting unit is reduced, so that the charging electric quantity of the light emitting stack structure emitting green light is reduced, the charging speed of the anode layer for charging the light emitting stack structure emitting green light is increased, and the light emitting efficiency is improved. And the smear problem of the display panel is improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a display panel and a display device. Background Art

[0002] With the development of flat-panel display technology, users' requirements for the stability of displays have gradually increased. In recent years, organic light emitting diode (OLED) displays have developed rapidly around the world, and OLED display technology has also been increasingly advanced. With the improvement of OLED technical capabilities and process improvements, the application areas of OLED displays are gradually expanding to medium and large sizes. In the field of medium and large-size OLED displays, the performance requirements of displays are higher, especially in terms of life and power consumption. Against this background, the application demand for long-life and high-efficiency stacked OLED devices has increased, and major display manufacturers have also invested resources in technology and product development, and launched stacked devices of various structures. However, compared with single-layer OLED devices, the stacked OLED device structure still has some problems in performance, such as ghosting problems, which need to be improved. Summary of the invention

[0003] The present application provides a display panel and a display device to improve the streaking problem of the display panel.

[0004] In a first aspect, the present application provides a display panel, comprising a light-emitting device layer, wherein the light-emitting device layer comprises:

[0005] Anode layer;

[0006] A cathode layer, arranged opposite to the anode layer;

[0007] A light-emitting stacked structure is arranged between the anode layer and the cathode layer, and the light-emitting stacked structure includes a green light-emitting unit, the highest occupied molecular orbital energy level of the green light-emitting main material in the green light-emitting unit is greater than or equal to -5.8 eV and less than or equal to -5.6 eV, and / or the hole mobility of the green light-emitting main material in the green light-emitting unit is greater than or equal to 10 -6 cm 2 / Vs and less than or equal to 10 -5 cm 2 / Vs.

[0008] In the display panel of some embodiments of the present application, the highest occupied molecular orbital energy level of the green light host material of the green light emitting unit is adjusted to be greater than or equal to -5.8 eV and less than or equal to -5.6 eV, and / or the hole mobility of the green light host material of the green light emitting unit is adjusted to be greater than or equal to 10 -6 cm 2 / Vs and less than or equal to 10-5 cm 2 / Vs, so as to reduce the ability of holes to be injected into the green light emitting unit and reduce the number of holes entering the green light emitting unit, thereby reducing the charging amount of the light emitting stack structure that emits green light in the light emitting stack structure, increasing the charging speed of the anode layer to charge the light emitting stack structure that emits green light, and improving the smear problem of the display panel. At the same time, the problem of poor performance such as the driving voltage of the green light emitting unit due to the excessively large highest occupied molecular orbital energy level of the green light host material in the green light emitting unit or the excessively small hole mobility is improved.

[0009] In a second aspect, the present application further provides a display panel, comprising a light-emitting device layer, wherein the light-emitting device layer comprises:

[0010] Anode layer;

[0011] A cathode layer, arranged opposite to the anode layer;

[0012] A light-emitting stack is arranged between the anode layer and the cathode layer, and the light-emitting stack includes a green light-emitting unit, an electron blocking unit and a hole transport layer; in one of the light-emitting stacks, the green light-emitting unit is located on the side of the electron blocking unit close to the cathode layer, the hole transport layer is located on the side of the electron blocking unit close to the anode layer, and the orthographic projection of the electron blocking unit on the anode layer overlaps with the orthographic projection of the green light-emitting unit on the anode layer; the highest occupied molecular orbital energy level of the electron blocking material of the electron blocking unit is greater than or equal to -5.7 eV and less than or equal to -5.5 eV, and / or the highest occupied molecular orbital energy level of the hole transport material of the hole transport layer is greater than or equal to -5.7 eV and less than or equal to -5.5 eV.

[0013] In the display panel of some embodiments of the present application, the highest occupied molecular orbital energy level of the electron blocking material of the electron blocking unit is adjusted to be greater than or equal to -5.7eV and less than or equal to -5.5eV, and / or, the highest occupied molecular orbital energy level of the hole transport material of the hole transport layer is adjusted to be greater than or equal to -5.7eV and less than or equal to -5.5eV, so as to effectively reduce the amount of holes injected at the interface between at least one of the electron blocking unit and the hole transport layer and the adjacent film layer, reduce the number of holes injected into the green light emitting unit, thereby reducing the charging amount of the light emitting stack structure that emits green light in multiple light emitting stack structures, and improve the charging speed of the anode layer charging the light emitting stack structure that emits green light, thereby improving the smear problem of the display panel. At the same time, the problem of excessively high highest occupied molecular orbital energy level of at least one of the electron blocking unit and the hole transport layer, which leads to an increase in the driving voltage of the green light emitting unit and other performance degradation is improved.

[0014] In a third aspect, the present application further provides a display panel, comprising a light-emitting device layer, wherein the light-emitting device layer comprises:

[0015] Anode layer;

[0016] A cathode layer, arranged opposite to the anode layer;

[0017] A light-emitting stack, arranged between the anode layer and the cathode layer, and comprising a green light-emitting unit, an electron blocking unit and a hole transport layer; in one of the light-emitting stacks, the green light-emitting unit is located on a side of the electron blocking unit close to the cathode layer, the hole transport layer is located on a side of the electron blocking unit close to the anode layer, and the orthographic projection of the electron blocking unit on the anode layer overlaps with the orthographic projection of the green light-emitting unit on the anode layer; the hole mobility of the electron blocking unit is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs, and / or, the hole mobility of the hole transport layer is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 - 4 cm 2 / Vs.

[0018] In the display panel of some embodiments of the present application, the hole mobility of the electron blocking unit is adjusted to be greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs, and / or, adjusting the hole mobility of the hole transport layer to be greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs, so as to effectively reduce the amount of holes injected at the interface between at least one of the electron blocking unit and the hole transport layer and the adjacent film layer, reduce the number of holes injected into the green light emitting unit, thereby reducing the charging amount of the light emitting stack structure emitting green light among the multiple light emitting stack structures, and increase the charging speed of the anode layer charging the light emitting stack structure emitting green light, thereby improving the smear problem of the display panel. At the same time, the problem of poor performance such as the driving voltage of the green light emitting unit being increased due to the low hole mobility of at least one of the electron blocking unit and the hole transport layer is improved.

[0019] In a fourth aspect, the present application further provides a display device, comprising the display panel of any of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the structure of display panels of some embodiments of the present application.

[0021] The reference numerals are as follows:

[0022] 100, display panel;

[0023] 10. Substrate;

[0024] 1. Light-emitting device layer;

[0025] 11, anode layer; 111, first anode; 112, second anode; 113, third anode;

[0026] 12, cathode layer;

[0027] 13, charge generation layer; 131, n-type charge generation layer; 132, p-type charge generation layer;

[0028] 14, luminous stacking structure;

[0029] 141, a first light-emitting stack;

[0030] 1411, first light emitting layer;

[0031] 1411A, a first green light emitting unit; 1411B, a first blue light emitting unit; 1411C, a first red light emitting unit;

[0032] 1412, a first electron blocking layer;

[0033] 1412A, a first electron blocking unit; 1412B, a second electron blocking unit; 1412C, a third electron blocking unit;

[0034] 1413, a first hole transport layer;

[0035] 1414, hole injection layer;

[0036] 1415, a first hole blocking layer; 216, a first electron transport layer;

[0037] 142, a second light-emitting stack;

[0038] 1421, second light emitting layer;

[0039] 1421A, a second green light emitting unit; 1421B, a second blue light emitting unit; 1421C, a second red light emitting unit;

[0040] 1422, a second electron blocking layer;

[0041] 1422A, a fourth electron blocking unit; 1422B, a fifth electron blocking unit; 1422C, a sixth electron blocking unit;

[0042] 1423, a second hole transport layer; 1424, a second hole blocking layer; 1425, a second electron transport layer; 1426, an electron injection layer;

[0043] 31, covering layer; 32, thin film encapsulation layer; 33, driving circuit layer. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0045] like Figure 1 As shown, the display panel 100 includes a substrate 10 and a light emitting device layer 1. The light emitting device layer 1 is disposed on the substrate 10. The light emitting device layer 1 includes an anode layer 11, a cathode layer 12 and a light emitting stack 14.

[0046] The anode layer 11 includes two transparent anode layers and a reflective anode layer located between the two transparent anode layers. The material of the transparent anode layer includes a transparent conductive material. The material of the reflective anode layer includes a metal. The anode layer 11 includes a first anode 111, a second anode 112 and a third anode 113 that are spaced apart from each other.

[0047] The cathode layer 12 is provided on the entire surface. The cathode layer 12 is transparent or semi-transparent. The cathode layer 12 includes at least one of metal materials such as magnesium and silver.

[0048] The light emitting stack 14 is used to emit light. Figure 1 As shown, a plurality of light emitting stacks 14 are stacked between the anode layer 11 and the cathode layer 12. In other embodiments, one light emitting stack 14 is disposed between the anode layer 11 and the cathode layer 12.

[0049] In some embodiments, when a plurality of light emitting stacks 14 are stacked between the anode layer 11 and the cathode layer 12 , the light emitting device layer 1 further includes a charge generation layer 13 . The charge generation layer 13 is disposed between adjacent light emitting stacks 14 .

[0050] Exemplarily, the plurality of light-emitting stacks 14 include a first light-emitting stack 141 and a second light-emitting stack 142. The first light-emitting stack 141 is located between the charge generation layer 13 and the anode layer 11. The second light-emitting stack 142 is located between the charge generation layer 13 and the cathode layer 12. In this way, the light-emitting effect of the display panel 100 is improved while reducing the manufacturing difficulty of the display panel 100.

[0051] It is understandable that the number of the light-emitting stacked structures 14 may also be three or more.

[0052] One charge generation layer 13 includes an n-type charge generation layer 131 and a p-type charge generation layer 132. In one charge generation layer 13, the n-type charge generation layer 131 is located on a side of the p-type charge generation layer 132 close to the anode layer 11.

[0053] Each light-emitting stack 14 includes a light-emitting layer. In some embodiments, the light-emitting layer includes a green light-emitting unit G. The green light-emitting unit G is an organic material layer, and can emit green light when a certain voltage is applied to the anode layer 11 and the cathode layer 12. Each green light-emitting unit G includes a green light main material and a green light dopant material. In the green light-emitting unit G, the mass proportion of the green light main material is greater than the mass proportion of the green light dopant material.

[0054] For example, Figure 1 As shown, the first light-emitting stack 141 includes a first light-emitting layer 1411, and the first light-emitting layer 1411 includes a first green light-emitting unit 1411A. The second light-emitting stack 142 includes a second light-emitting layer 1421, and the second light-emitting layer 1421 includes a second green light-emitting unit 1421A. In the stacking direction of the plurality of light-emitting stacks 14, the first green light-emitting unit 1411A overlaps with the second green light-emitting unit 1421A. The orthographic projections of the first green light-emitting unit 1411A and the second green light-emitting unit 1421A on the substrate 10 overlap with the orthographic projection of the first anode 111 on the substrate 10.

[0055] In some embodiments, the green light host material in the first green light emitting unit 1411A and the second green light emitting unit 1421A is the same. Thus, the first green light emitting unit 1411A and the second green light emitting unit 1421A can be made of the same material, simplifying the manufacturing process of the display panel 100 .

[0056] In some other embodiments, the green light host materials in the first green light emitting unit 1411A and the second green light emitting unit 1421A may also be different, so as to meet different functional requirements of the first green light emitting unit 1411A and the second green light emitting unit 1421A.

[0057] In some embodiments, the highest occupied molecular orbital (HOMO) energy level of the green light main material in at least one green light emitting unit G is greater than or equal to -5.8 eV and less than or equal to -5.6 eV. In this way, the highest occupied molecular orbital energy level of the green light main material in at least one green light emitting unit G is deepened to effectively reduce the ability of hole injection into the green light emitting unit G, thereby reducing the charging amount of the light emitting stack structure emitting green light in the light emitting stack structure 14, increasing the charging speed of the anode layer 11 charging the light emitting stack structure emitting green light, and improving the smear problem of the display panel 100. At the same time, the problem of poor performance such as the driving voltage of the green light emitting unit being increased due to the high highest occupied molecular orbital energy level of the green light main material in the green light emitting unit is improved.

[0058] Optionally, the highest occupied molecular orbital energy level of the green light host material in at least one green light emitting unit G is greater than or equal to -5.75 eV and less than or equal to -5.65 eV. Optionally, the highest occupied molecular orbital energy level of the green light host material in at least one green light emitting unit G is greater than or equal to -5.8 eV and less than or equal to -5.7 eV.

[0059] Exemplarily, the highest occupied molecular orbital energy level of the green light host material in at least one green light emitting unit G includes a combination of one or more of the following highest occupied molecular orbital energy levels: -5.61eV, -5.62eV, -5.63eV, -5.64eV, -5.65eV, -5.66eV, -5.67eV, -5.68eV, -5.69eV, -5.70eV, -5.71eV, -5.72eV, -5.73eV, -5.74eV, -5.75eV, -5.76eV, -5.77eV, -5.78eV, -5.79eV and -5.80eV.

[0060] In some embodiments, the highest occupied molecular orbital energy level of the green light main material in the green light emitting unit G of each of the multiple light emitting stacks 14 is greater than or equal to -5.8eV and less than or equal to -5.6eV. In this way, the highest occupied molecular orbital energy level of the green light main material of the green light emitting unit G of each of the multiple light emitting stacks 14 is adjusted to minimize the charging amount of the light emitting stack that emits green light in the multiple light emitting stacks 14, maximize the charging speed of the anode layer 11 charging the light emitting stack that emits green light, and better improve the smear problem of the display panel 100. At the same time, the problem of performance degradation such as the driving voltage of the green light emitting unit being increased due to the excessive highest occupied molecular orbital energy level of the green light main material in the green light emitting unit is improved. In addition, multiple green light emitting units use the same material to simplify the manufacturing process of the display panel 100.

[0061] Illustratively, the highest occupied molecular orbital energy level of the green light host material in the first green light emitting unit 1411A and the second green light emitting unit 1421A is greater than or equal to −5.8 eV and less than or equal to −5.6 eV.

[0062] It is understandable that in other embodiments, the highest occupied molecular orbital energy level of the green light host material of one of the first green light emitting unit 1411A and the second green light emitting unit 1421A may be greater than or equal to -5.8 eV and less than or equal to -5.6 eV.

[0063] In some embodiments, the hole mobility of the green light host material in at least one green light emitting unit G is greater than or equal to 10 -6 cm 2 / Vs and less than or equal to 10 -5 cm 2 / Vs. In this way, the hole mobility of the green light host material of the green light emitting unit G is adjusted to be greater than or equal to 10 -6 cm 2 / Vs and less than or equal to 10 -5 cm 2 / Vs, so as to reduce the number of holes entering the green light emitting unit G, thereby reducing the charging amount of the light emitting stack structure emitting green light in the light emitting stack structure 14, increasing the charging speed of the anode layer 11 for charging the light emitting stack structure emitting green light, and improving the smear problem of the display panel 100. At the same time, the problem of poor performance such as the driving voltage of the green light emitting unit being increased due to the low hole mobility of the green light main material in the green light emitting unit is improved.

[0064] Optionally, the hole mobility of the green light host material in at least one green light emitting unit G is greater than or equal to 2*10 - 6 cm 2 / Vs and less than or equal to 0.8*10 -5 cm 2 / Vs. Optionally, the hole mobility of the green light host material in at least one green light emitting unit is greater than or equal to 4*10 -6 cm 2 / Vs and less than or equal to 0.7*10 -5 cm 2 / Vs.

[0065] Exemplarily, the hole mobility of the green light host material in at least one green light emitting unit G includes a combination of one or more of the following hole mobilities: 10 -6 cm 2 / Vs,2*10 -6 cm 2 / Vs,3*10-6 cm 2 / Vs、4*10 -6 cm 2 / Vs,5*10 -6 cm 2 / Vs,6*10 -6 cm 2 / Vs、7*10 -6 cm 2 / Vs、8*10 -6 cm 2 / Vs、9*10 -6 cm 2 / Vs and 10 -5 cm 2 / Vs.

[0066] In some embodiments, the hole mobility of the green light host material in the green light emitting unit G of each of the plurality of light emitting stacks 14 is greater than or equal to 10 -6 cm 2 / Vs and less than or equal to 10 -5 cm 2 / Vs. In this way, the number of holes entering the green light emitting unit G is reduced, thereby reducing the charging amount of the light emitting stacked structure emitting green light in the multiple light emitting stacked structures 14, increasing the charging speed of the anode layer 11 for charging the light emitting stacked structure emitting green light, and improving the smear problem of the display panel 100. At the same time, the problem of poor performance such as the driving voltage of the green light emitting unit being increased due to the low hole mobility of the green light main material in the green light emitting unit is improved. In addition, the multiple green light emitting units use the same material to simplify the manufacturing process of the display panel 100.

[0067] Exemplarily, the hole mobility of the green light host material in the first green light emitting unit 1411A and the second green light emitting unit 1421A is greater than or equal to 10 -6 cm 2 / Vs and less than or equal to 10 -5 cm 2 / Vs.

[0068] It is understandable that in other embodiments, the hole mobility of the green light host material of one of the first green light emitting unit 1411A and the second green light emitting unit 1421A may be greater than or equal to 10 -6 cm 2 / Vs and less than or equal to 10 - 5 cm 2 / Vs.

[0069] In some embodiments, the green light host material in at least one green light emitting unit G may include at least one of a p-type green light host material and an n-type green light host material, but is not limited thereto. Among them, the p-type green light host material includes but is not limited to at least one of a carbazole compound and an indolecarbazole compound. The n-type green light host material includes but is not limited to at least one of a triazine compound, a dibenzofuran compound, and a triphenylene compound. In this way, by optimizing the green light host material in the green light emitting unit G, the highest occupied molecular orbital energy level of the green light host material in at least one green light emitting unit is adjusted to be greater than or equal to -5.8 eV and less than or equal to -5.6 eV, or the hole mobility of the green light host material in at least one green light emitting unit is adjusted to be greater than or equal to 10 -6 cm 2 / Vs and less than or equal to 10 - 5 cm 2 / Vs.

[0070] In some embodiments, each light-emitting layer further includes a blue light-emitting unit and a red light-emitting unit. The orthographic projection of the blue light-emitting unit on the substrate 10 overlaps with the orthographic projection of the second anode 112 on the substrate 10. The orthographic projection of the red light-emitting unit on the substrate 10 overlaps with the orthographic projection of the third anode 113 on the substrate 10.

[0071] Exemplarily, the first light-emitting layer 1411 further includes a first blue light-emitting unit 1411B and a first red light-emitting unit 1411C. The second light-emitting layer 1421 further includes a second blue light-emitting unit 1421B and a second red light-emitting unit 1421C. In the stacking direction of the plurality of light-emitting stacks 14, the first blue light-emitting unit 1411B overlaps with the second blue light-emitting unit 1421B, and the first red light-emitting unit 1411C overlaps with the second red light-emitting unit 1421C.

[0072] In some embodiments, the light emitting stack 14 further includes an electron blocking unit FLG. In a light emitting stack 14, the green light emitting unit G is located on the side of the electron blocking unit FLG close to the cathode layer 12. The orthographic projection of the electron blocking unit FLG on the anode layer 11 overlaps with the orthographic projection of the green light emitting unit G on the anode layer 11.

[0073] Exemplarily, the first light-emitting stack 141 includes a first electron blocking layer 1412, which is located on the side of the first light-emitting layer 1411 close to the anode layer 11. The first electron blocking layer 1412 includes a first electron blocking unit 1412A, which is overlapped and in contact with the first green light-emitting unit 1411A. The second light-emitting stack 142 includes a second electron blocking layer 1422, which is located on the side of the second light-emitting layer 1421 close to the anode layer 11. The second electron blocking layer 1422 includes a fourth electron blocking unit 1422A, which is overlapped and in contact with the second green light-emitting unit 1421A. In the stacking direction of the plurality of light-emitting stacks 14, the first electron blocking unit 1412A overlaps with the fourth electron blocking unit 1422A. The orthographic projections of the first electron blocking unit 1412A and the fourth electron blocking unit 1422A on the substrate 10 overlap with the orthographic projections of the first green light emitting unit 1411A and the second green light emitting unit 1421A on the substrate 10 .

[0074] In some embodiments, the highest occupied molecular orbital energy level of the electron blocking material of at least one electron blocking unit FLG is greater than or equal to -5.7 eV and less than or equal to -5.5 eV. In this way, the highest occupied molecular orbital energy level of the electron blocking material of the electron blocking unit FLG overlapping with the green light emitting unit G is adjusted to be greater than or equal to -5.7 eV and less than or equal to -5.5 eV, so as to effectively reduce the amount of holes injected at the interface between the electron blocking unit FLG and the adjacent film layer (for example, the green light emitting unit), and adjust the number of holes injected into the green light emitting unit G, thereby reducing the charging amount of the light emitting stacking structure emitting green light in the multiple light emitting stacking structures 14, and improving the charging speed of the anode layer 11 charging the light emitting stacking structure emitting green light, thereby improving the smear problem of the display panel 100. At the same time, the problem of the excessively high highest occupied molecular orbital energy level of the electron blocking material of the electron blocking unit FLG overlapping with the green light emitting unit G, which leads to the increase in the driving voltage of the green light emitting unit G and other performance degradation is improved.

[0075] Optionally, the highest occupied molecular orbital energy level of the electron blocking material of at least one electron blocking unit FLG is greater than or equal to -5.7 eV and less than or equal to -5.6 eV. Optionally, the highest occupied molecular orbital energy level of the electron blocking material of at least one electron blocking unit FLG is greater than or equal to -5.65 eV and less than or equal to -5.55 eV.

[0076] Exemplarily, the highest occupied molecular orbital energy level of the electron blocking material of at least one electron blocking unit FLG includes a combination of one or more of the following highest occupied molecular orbital energy levels: -5.51eV, -5.52eV, -5.53eV, -5.54eV, -5.55eV, -5.56eV, -5.57eV, -5.58eV, -5.59eV, -5.60eV, -5.61eV, -5.62eV, -5.63eV, -5.64eV, -5.65eV, -5.66eV, -5.67eV, -5.68eV, -5.69eV and -5.70eV.

[0077] In some embodiments, the highest occupied molecular orbital energy level of the electron blocking material of the electron blocking unit FLG overlapping with each green light emitting unit G in the multiple light emitting stacks 14 is greater than or equal to -5.7eV and less than or equal to -5.5eV. In this way, while improving the smear problem of the display panel 100, the problem of the highest occupied molecular orbital energy level of the electron blocking material of the electron blocking unit FLG overlapping with the green light emitting unit G is improved, which leads to the problem of poor performance such as the driving voltage of the green light emitting unit increasing. In addition, the materials of the multiple electron blocking units overlapping with the multiple green light emitting units can be the same, simplifying the manufacturing process of the display panel 100.

[0078] Exemplarily, the highest occupied molecular orbital energy level of the electron blocking materials of the first electron blocking unit 1412A and the fourth electron blocking unit 1422A is greater than or equal to −5.7 eV and less than or equal to −5.5 eV.

[0079] It is understandable that in other embodiments, the highest occupied molecular orbital energy level of the electron blocking material of one of the first electron blocking unit 1412A and the fourth electron blocking unit 1422A may be greater than or equal to -5.7 eV and less than or equal to -5.5 eV.

[0080] In some embodiments, the light-emitting stack 14 further includes an electron blocking unit FLG. In one light-emitting stack 14, the green light-emitting unit G is located on the side of the electron blocking unit FLG close to the cathode layer 12. The positive projection of the electron blocking unit FLG on the anode layer 11 overlaps with the positive projection of the green light-emitting unit G on the anode layer 11. The hole mobility of at least one electron blocking unit FLG is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 In this way, the hole mobility of the electron blocking unit FLG overlapping with the green light emitting unit G is adjusted to be greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4cm 2 / Vs, so as to effectively reduce the amount of holes injected at the interface between the electron blocking unit FLG and the adjacent film layer, reduce the number of holes injected into the green light emitting unit G, thereby reducing the charging amount of the light emitting stacking structure emitting green light in the multiple light emitting stacking structures 14, and improve the charging speed of the anode layer 11 for charging the light emitting stacking structure emitting green light, thereby improving the smear problem of the display panel 100. At the same time, the problem of poor performance such as the driving voltage of the green light emitting unit being increased due to the small hole mobility of the electron blocking unit is improved.

[0081] Optionally, the hole mobility of at least one electron blocking unit FLG is greater than or equal to 2*10 -5 cm 2 / Vs and less than or equal to 0.8*10 -4 cm 2 / Vs. Optionally, the hole mobility of at least one electron blocking unit is greater than or equal to 4*10 - 5 cm 2 / Vs and less than or equal to 0.7*10 -4 cm 2 / Vs.

[0082] Exemplarily, the hole mobility of at least one electron blocking unit FLG includes a combination of one or more of the following hole mobilities: 10 -5 cm 2 / Vs,2*10 -5 cm 2 / Vs,3*10 -5 cm 2 / Vs、4*10 -5 cm 2 / Vs,5*10 -5 cm 2 / Vs,6*10 - 5 cm 2 / Vs、7*10 -5 cm 2 / Vs、8*10 -5 cm 2 / Vs、9*10 -5 cm 2 / Vs and 10 -4 cm 2 / Vs.

[0083] In some embodiments, the hole mobility of each electron blocking unit FLG overlapping with the green light emitting unit G in the plurality of light emitting stacks 14 is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4cm 2 In this way, the hole mobility of the electron blocking unit FLG overlapping with the green light emitting unit G is adjusted to be greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs, so as to effectively reduce the amount of holes injected at the interface between the electron blocking unit and the adjacent film layer (green light emitting unit), reduce the number of holes injected into the green light emitting unit G, thereby reducing the charging amount of the light emitting stack structure that emits green light in the multiple light emitting stack structures 14, and improving the charging speed of the anode layer 11 to charge the light emitting stack structure that emits green light, thereby improving the smear problem of the display panel 100. At the same time, the problem of poor performance such as the driving voltage of the green light emitting unit being increased due to the small hole mobility of the electron blocking unit FLG is improved. In addition, the same material is used for the multiple electron blocking units FLG of the green light emitting unit to simplify the manufacturing process of the display panel 100.

[0084] Exemplarily, the hole mobility of the first electron blocking unit 1412A and the fourth electron blocking unit 1422A is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs.

[0085] It is understood that in other embodiments, the hole mobility of one of the first electron blocking unit 1412A and the fourth electron blocking unit 1422A may be greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs.

[0086] In some embodiments, the material of at least one electron blocking unit FLG (the first electron blocking unit 1412A and the fourth electron blocking unit 1422A) can be selected from at least one of diphenylamine compounds, carbazole compounds and triphenylamine compounds. In this way, by optimizing the material of the electron blocking unit, the highest occupied molecular orbital energy level of the electron blocking material of at least one electron blocking unit is adjusted to be greater than or equal to -5.7 eV and less than or equal to -5.5 eV, or the hole mobility of at least one electron blocking unit is adjusted to be greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 - 4 cm 2 / Vs.

[0087] In some embodiments, Figure 1As shown, the first electron blocking layer 1412 may further include a second electron blocking unit 1412B, and the second electron blocking layer 1422 may further include a fifth electron blocking unit 1422B. The orthographic projections of the second electron blocking unit 1412B and the fifth electron blocking unit 1422B on the substrate 10 overlap with the orthographic projections of the second blue light emitting unit 1421B and the first blue light emitting unit 1411B on the substrate 10. The thickness of the second electron blocking unit 1412B and the fifth electron blocking unit 1422B may be less than the thickness of the first electron blocking unit 1412A and the fourth electron blocking unit 1422A, but is not limited thereto.

[0088] In some embodiments, Figure 1 As shown, the first electron blocking layer 1412 may further include a third electron blocking unit 1412C, and the second electron blocking layer 1422 may further include a sixth electron blocking unit 1422C. The orthographic projections of the third electron blocking unit 1412C and the sixth electron blocking unit 1422C on the substrate 10 overlap with the orthographic projections of the second red light emitting unit 1421C and the first red light emitting unit 1411C on the substrate 10. The thickness of the third electron blocking unit 1412C and the sixth electron blocking unit 1422C may be greater than the thickness of the first electron blocking unit 1412A and the fourth electron blocking unit 1422A, but is not limited thereto.

[0089] In some embodiments, Figure 1 As shown, the light emitting stack 14 further includes a hole transport layer HTL. In one light emitting stack 14 , the green light emitting unit G is located on a side of the hole transport layer HTL close to the cathode layer 12 .

[0090] Exemplarily, the first light-emitting stack 141 includes a first light-emitting layer 1411, a first electron blocking layer 1412, and a first hole transport layer 1413, and the first hole transport layer 1413 is located on the side of the first light-emitting layer 1411 close to the anode layer 11. The first electron blocking layer 1412 is located between the first hole transport layer 1413 and the first light-emitting layer 1411. The first hole transport layer 1413 is in contact with the first electron blocking layer 1412. The second light-emitting stack 142 includes a second light-emitting layer 1421, a second electron blocking layer 1422, and a second hole transport layer 1423, and the second hole transport layer 1423 is located on the side of the second light-emitting layer 1421 close to the anode layer 11. The second electron blocking layer 1422 is located between the second hole transport layer 1423 and the second light-emitting layer 1421. The second hole transport layer 1423 is in contact with the second electron blocking layer 1422.

[0091] In some embodiments, the highest occupied molecular orbital energy level of the hole transport material of at least one hole transport layer HTL is greater than or equal to -5.7eV and less than or equal to -5.5eV. In this way, the highest occupied molecular orbital energy level of the hole transport material of at least one hole transport layer HTL is adjusted to be greater than or equal to -5.7eV and less than or equal to -5.5eV, so as to effectively reduce the amount of holes injected at the interface between the hole transport layer and the adjacent film layer (electron blocking layer), reduce the number of holes injected into the green light emitting unit G, thereby reducing the charging amount of the light emitting stack structure emitting green light in the multiple light emitting stack structures 14, and improve the charging speed of the anode layer 11 charging the light emitting stack structure emitting green light, thereby improving the smear problem of the display panel 100. At the same time, the problem of excessively high highest occupied molecular orbital energy level of the hole transport material of the hole transport layer, which leads to an increase in the driving voltage of the green light emitting unit and other performance degradation is improved.

[0092] Optionally, the highest occupied molecular orbital energy level of the hole transport material of at least one hole transport layer HTL is greater than or equal to -5.7 eV and less than or equal to -5.6 eV. Optionally, the highest occupied molecular orbital energy level of the hole transport material of at least one hole transport layer is greater than or equal to -5.65 eV and less than or equal to -5.55 eV.

[0093] Exemplarily, the highest occupied molecular orbital energy level of the hole transport material of at least one hole transport layer HTL includes a combination of one or more of the following highest occupied molecular orbital energy levels: -5.51eV, -5.52eV, -5.53eV, -5.54eV, -5.55eV, -5.56eV, -5.57eV, -5.58eV, -5.59eV, -5.60eV, -5.61eV, -5.62eV, -5.63eV, -5.64eV, -5.65eV, -5.66eV, -5.67eV, -5.68eV, -5.69eV and -5.70eV.

[0094] In some embodiments, the highest occupied molecular orbital energy level of the hole transport material of the hole transport layer HTL in each light-emitting stack 14 is greater than or equal to -5.7 eV and less than or equal to -5.5 eV. In this way, the smear problem of the display panel 100 is improved, and the problem of performance degradation such as the driving voltage of the green light emitting unit being increased due to the excessive highest occupied molecular orbital energy level of the hole transport layer is improved. In addition, the material of multiple hole transport layers can be the same, simplifying the manufacturing process of the display panel 100.

[0095] For example, the highest occupied molecular orbital energy level of the hole transport materials of the first hole transport layer 1413 and the second hole transport layer 1423 is greater than or equal to −5.7 eV and less than or equal to −5.5 eV.

[0096] It is understandable that in other embodiments, the highest occupied molecular orbital energy level of the hole transport material of one of the first hole transport layer 1413 and the second hole transport layer 1423 may be greater than or equal to −5.7 eV and less than or equal to −5.5 eV.

[0097] In some embodiments, the hole mobility of at least one hole transport layer HTL is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs. In this way, the hole mobility of at least one hole transport layer HTL is adjusted to be greater than or equal to 10 - 5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs, reducing the number of holes injected into the green light emitting unit G, so as to effectively reduce the amount of holes injected at the interface between the hole transport layer and the adjacent film layer, thereby reducing the charging power of the light emitting stack structure emitting green light in the multiple light emitting stack structures 14, increasing the charging speed of the anode layer 11 for charging the light emitting stack structure emitting green light, and improving the smear problem of the display panel 100. At the same time, the problem of poor performance such as the driving voltage of the green light emitting unit being increased due to the low hole mobility of the hole transport layer is improved.

[0098] Optionally, the hole mobility of at least one hole transport layer HTL is greater than or equal to 2*10 -5 cm 2 / Vs and less than or equal to 0.8*10 -4 cm 2 / Vs. Optionally, the hole mobility of at least one hole transport layer HTL is greater than or equal to 4*10 -5 cm 2 / Vs and less than or equal to 0.7*10 -4 cm 2 / Vs.

[0099] Exemplarily, the hole mobility of at least one hole transport layer HTL includes a combination of one or more of the following hole mobilities: 10 -5 cm 2 / Vs,2*10 -5 cm 2 / Vs,3*10 -5 cm 2 / Vs、4*10 -5 cm 2 / Vs,5*10 -5 cm 2 / Vs,6*10- 5 cm 2 / Vs、7*10 -5 cm 2 / Vs、8*10 -5 cm 2 / Vs、9*10 -5 cm 2 / Vs and 10 -4 cm 2 / Vs.

[0100] In some embodiments, the hole mobility of each hole transport layer HTL in the plurality of light-emitting stacks 14 is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs. In this way, the hole mobility of the hole transport layer is adjusted to be greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs, so as to effectively reduce the amount of holes injected at the interface between the hole transport layer and the adjacent film layer (electron blocking unit), reduce the number of holes injected into the green light emitting unit G, thereby reducing the charging amount of the light emitting stack structure that emits green light in the multiple light emitting stack structures 14, and improving the charging speed of the anode layer 11 to charge the light emitting stack structure that emits green light, thereby improving the smear problem of the display panel 100. At the same time, the problem of poor performance such as the driving voltage of the green light emitting unit being increased due to the small hole mobility of the hole transport layer is improved. In addition, multiple hole transport layers use the same material to simplify the manufacturing process of the display panel 100.

[0101] Exemplarily, the hole mobility of the first hole transport layer 1413 and the second hole transport layer 1423 is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs.

[0102] In some embodiments, the hole transport material of at least one hole transport layer HTL can be selected from at least one of diphenylamine compounds, carbazole compounds and triphenylamine compounds. Thus, by optimizing the hole transport material, the hole mobility of at least one hole transport layer is adjusted to be greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs, or, the highest occupied molecular orbital energy level of the hole transport material of at least one hole transport layer is adjusted to be greater than or equal to -5.7 eV and less than or equal to -5.5 eV.

[0103] In some embodiments, the highest occupied molecular orbital energy level of the hole transport material of at least one hole transport layer HTL is 0.05 eV to 0.2 eV less than the highest occupied molecular orbital energy level of the electron blocking material of at least one electron blocking unit (at least one of the first electron blocking unit 1412A and the second electron blocking unit 1412B).

[0104] It is understood that in other embodiments, the hole mobility of one of the first hole transport layer 1413 and the second hole transport layer 1423 may be greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs.

[0105] It should be noted that, compared with other common film layers in each light-emitting stack 14 , adjusting the highest occupied molecular orbital energy level of the hole transport material of the hole transport layer HTL, or reducing the hole mobility of the hole transport layer, has less impact on the light-emitting stack 14 .

[0106] In some embodiments, Figure 1 As shown, the first light-emitting stacked structure 141 further includes a hole injection layer 1414 , and the hole injection layer 1414 is located between the first hole transport layer 1413 and the anode layer 11 .

[0107] In some embodiments, Figure 1 As shown, the first light-emitting stacked structure 141 further includes a first hole blocking layer 1415 , and the first hole blocking layer 1415 is located between the first light-emitting layer 1411 and the charge generating layer 13 .

[0108] In some embodiments, Figure 1 As shown, the first light-emitting stack 141 further includes a first electron transport layer 1416, which is located between the first light-emitting layer 1411 and the charge generation layer 13. When the first light-emitting stack 141 includes a first hole blocking layer 1415, the first electron transport layer 1416 is located between the first hole blocking layer 1415 and the charge generation layer 13.

[0109] In some embodiments, Figure 1 As shown, the second light-emitting stack 142 further includes a second hole blocking layer 1424 , and the second hole blocking layer 1424 is located between the second light-emitting layer 1421 and the cathode layer 12 .

[0110] In some embodiments, Figure 1 As shown, the second light-emitting stack 142 further includes a second electron transport layer 1425, which is located between the second light-emitting layer 1421 and the cathode layer 12. When the second light-emitting stack 142 includes a second hole blocking layer 1424, the second electron transport layer 1425 is located between the second hole blocking layer 1424 and the electron injection layer 1426.

[0111] In some embodiments, Figure 1 As shown, the second light-emitting stack 142 further includes an electron injection layer 1426, which is located between the cathode layer 12 and the second light-emitting layer 1421. When the second light-emitting stack 142 includes a second electron transport layer 1425, the electron injection layer 1426 is located between the second electron transport layer 1425 and the cathode layer 12.

[0112] In some embodiments, Figure 1 As shown, the display panel 100 further includes a pixel driving circuit layer 33, which is disposed between the substrate 10 and the light emitting device layer 1. The pixel driving circuit layer 33 includes a plurality of pixel driving circuits, which are respectively connected to a plurality of anodes of the anode layer 11.

[0113] In some embodiments, Figure 1 As shown, the display panel 100 further includes a cover layer 31, which is located on the side of the cathode layer 12 away from the anode layer 11. The refractive index of the cover layer 31 is greater than the refractive index of the cathode layer 12 to improve the light extraction efficiency of the light emitting device layer 1. The cover layer 31 may include an organic material.

[0114] In some embodiments, Figure 1 As shown, the display panel 100 further includes a thin film encapsulation layer 32, which is located on a side of the cover layer 31 away from the cathode layer 12. The thin film encapsulation layer 32 may include two inorganic encapsulation layers and an organic encapsulation layer located between the two inorganic encapsulation layers.

[0115] Based on the same inventive concept, the present application also provides a display device, which includes the display panel 100 of any of the above embodiments.

[0116] In summary, in the display panel and display of some embodiments of the present application, the hole-related performance of the light-emitting stack is adjusted to reduce the charging amount of the light-emitting stack that emits green light among multiple light-emitting stacks. Specifically, the highest occupied molecular orbital energy level of at least one of the green light main material in the green light emitting unit, the electron blocking material of the electron blocking unit overlapping with the green light emitting unit, and the hole transport material of the hole transport layer is adjusted, and / or the hole mobility of at least one of the green light main material in the green light emitting unit, the electron blocking unit overlapping with the green light emitting unit, and the hole transport layer is adjusted, and the holes injected into the green light emitting unit are adjusted to reduce the charging amount of the light-emitting stack that emits green light among multiple light-emitting stacks, increase the charging speed of the anode layer charging the light-emitting stack that emits green light, and improve the ghosting problem of the display panel.

[0117] It should be noted that the applicant has found through a large number of creative experimental studies that adjusting the hole-related properties of the light-emitting stack can more significantly adjust the charging capacity of the green light-emitting stack than adjusting the electron-related properties of the light-emitting stack.

[0118] The technical solution of the present application is verified below in combination with the green light emitting devices of the embodiments and comparative examples.

[0119] The green light emitting device includes a cathode layer, an anode layer and a green light emitting stack, and the green light emitting stack is located between the cathode layer and the anode layer. The anode layer includes a first ITO layer (thickness 40nm), an Ag layer (thickness 140nm) and a second ITO layer (thickness 20nm) stacked in sequence. The cathode layer is a magnesium-silver alloy layer (thickness 15nm). The green light emitting stack structure includes a hole injection layer (the material is 1,4,5,8,9,11-hexaazabenzonitrile (HATCN), with a thickness of 10nm), a hole transport layer (the material is 1-bis[4-[N,NN-di(4-methylphenyl)amino]phenyl]-cyclohexane (TAPC), with a thickness of 20nm), an electron blocking layer (the material is 4,4,4-tri(N-carbazolyl)-triphenylamine (TCTA), with a thickness of 15nm), a green light emitting unit (including a green light main material and a green light doping material, the green light main material is a carbazole compound, the green light doping material is an iridium complex, the mass content of the green light main material in the green light emitting unit is 5%, and the thickness is 40nm), Hole blocking layer (material is 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi), thickness is 4nm), electron transport layer (material is 1,3,5-tris(3-pyridyl-3-phenyl)benzene (TmPyPB), thickness is 10-40nm), N-type charge generation layer (material is ytterbium-doped 4,7-diphenyl-1,10-phenanthroline (Bphen:Yb), thickness is 10nm, the mass percentage of ytterbium in the electron transport layer is 3%), P-type charge generation layer (material is 4,5,8,9,11-hexaazabenzonitrile (HATCN), thickness is 10nm) and electron injection layer (material is ytterbium, thickness is 1-2nm).

[0120] Moreover, the green light emitting devices of Examples 1 to 3 and Comparative Example 1 are basically similar, except that the highest occupied molecular orbital energy levels of the green light host materials of the four are different. The green light host materials of the four are all carbazole compounds, and the modification groups of the carbazole compounds of the four are different.

[0121] The green light emitting devices of Examples 4 to 6 and Comparative Example 2 are basically similar, except that the hole mobility of the green light host materials of the four are different. The green light host materials of the four are all carbazole compounds, and the modification groups of the carbazole compounds of the four are different.

[0122] Table 1 Charging capacity of green light emitting devices of Examples 1 to 3 and Comparative Example 1

[0123]

[0124] It can be seen from Table 1 that the charging capacity of the green light emitting devices of Examples 1 to 3 is less than that of the green light emitting device of Comparative Example 1. Therefore, the highest occupied molecular orbital energy level of the green light host material is -5.8 eV to -5.6 eV, which can reduce the charging capacity of the green light emitting device.

[0125] Table 2 Charging capacity of green light emitting devices of Examples 4 to 6 and Comparative Example 2

[0126]

[0127] It can be seen from Table 2 that the charging capacity of the green light emitting devices of Examples 4 to 6 is less than that of the green light emitting device of Comparative Example 2. Therefore, the hole mobility of the green light host material is 10 -6 cm 2 / Vs~10 -5 cm 2 / Vs, which can reduce the charging capacity of the green light emitting device.

[0128] The description of the above embodiments is only used to help understand the technical solutions and core ideas of the present application. Ordinary technical personnel in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A display panel, characterized in that: The invention comprises a light emitting device layer, wherein the light emitting device layer comprises: Anode layer; A cathode layer, arranged opposite to the anode layer; A light-emitting stacked structure is arranged between the anode layer and the cathode layer, and the light-emitting stacked structure includes a green light-emitting unit, the highest occupied molecular orbital energy level of the green light-emitting main material in the green light-emitting unit is greater than or equal to -5.8 eV and less than or equal to -5.6 eV, and / or the hole mobility of the green light-emitting main material in the green light-emitting unit is greater than or equal to 10 - 6 cm 2 / Vs and less than or equal to 10 -5 cm 2 / Vs.

2. The display panel according to claim 1, characterized in that: The highest occupied molecular orbital energy level of the green light host material in the green light emitting unit is greater than or equal to -5.75 eV and less than or equal to -5.65 eV.

3. The display panel according to claim 1 or 2, characterized in that: The light-emitting stack also includes an electron blocking unit. In one of the light-emitting stacks, the green light-emitting unit is located on a side of the electron blocking unit close to the cathode layer, the orthographic projection of the electron blocking unit on the anode layer overlaps with the orthographic projection of the green light-emitting unit on the anode layer, and the highest occupied molecular orbital energy level of the electron blocking material of the electron blocking unit is greater than or equal to -5.7 eV and less than or equal to -5.5 eV.

4. The display panel according to claim 3, characterized in that: The highest occupied molecular orbital energy level of the electron blocking material of the electron blocking unit is greater than or equal to -5.7 eV and less than or equal to -5.6 eV.

5. The display panel according to claim 1 or 2, characterized in that: The light-emitting stack further comprises an electron blocking unit, wherein in one of the light-emitting stacks, the green light-emitting unit is located on a side of the electron blocking unit close to the cathode layer, the orthographic projection of the electron blocking unit on the anode layer overlaps with the orthographic projection of the green light-emitting unit on the anode layer, and the hole mobility of the electron blocking unit is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs.

6. The display panel according to claim 1 or 2, characterized in that: The light-emitting stack also includes a hole transport layer. In one of the light-emitting stacks, the green light-emitting unit is located on a side of the hole transport layer close to the cathode layer. The highest occupied molecular orbital energy level of the hole transport material of the hole transport layer is greater than or equal to -5.7 eV and less than or equal to -5.5 eV.

7. The display panel according to claim 6, characterized in that: The highest occupied molecular orbital energy level of the hole transport material of the hole transport layer is greater than or equal to -5.7 eV and less than or equal to -5.6 eV.

8. The display panel according to claim 1 or 2, characterized in that: The light-emitting stack further comprises a hole transport layer. In one of the light-emitting stacks, the green light-emitting unit is located on a side of the hole transport layer close to the cathode layer. The hole mobility of the hole transport layer is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs.

9. The display panel according to any one of claims 1 or 2, characterized in that: The number of the light-emitting stacked structures is multiple, the display panel further includes a charge generation layer, the charge generation layer is located between two adjacent light-emitting stacked structures, each of the light-emitting stacked structures includes the green light-emitting unit, the blue light-emitting unit and the red light-emitting unit; and / or, The green light host material includes at least one of a p-type green light host material and an n-type green light host material, the p-type green light host material is selected from at least one of carbazole compounds and indolecarbazole compounds, and the n-type green light host material is selected from at least one of triazine compounds, dibenzofuran compounds and triphenylene compounds.

10. A display panel, characterized in that: The invention comprises a light emitting device layer, wherein the light emitting device layer comprises: Anode layer; A cathode layer, arranged opposite to the anode layer; A light-emitting stack is arranged between the anode layer and the cathode layer, and the light-emitting stack includes a green light-emitting unit, an electron blocking unit and a hole transport layer; in one of the light-emitting stacks, the green light-emitting unit is located on the side of the electron blocking unit close to the cathode layer, the hole transport layer is located on the side of the electron blocking unit close to the anode layer, and the orthographic projection of the electron blocking unit on the anode layer overlaps with the orthographic projection of the green light-emitting unit on the anode layer; the highest occupied molecular orbital energy level of the electron blocking material of the electron blocking unit is greater than or equal to -5.7 eV and less than or equal to -5.5 eV, and / or the highest occupied molecular orbital energy level of the hole transport material of the hole transport layer is greater than or equal to -5.7 eV and less than or equal to -5.5 eV.

11. A display panel, characterized in that: The invention comprises a light emitting device layer, wherein the light emitting device layer comprises: Anode layer; A cathode layer, arranged opposite to the anode layer; A light-emitting stack, arranged between the anode layer and the cathode layer, and comprising a green light-emitting unit, an electron blocking unit and a hole transport layer; in one of the light-emitting stacks, the green light-emitting unit is located on a side of the electron blocking unit close to the cathode layer, the hole transport layer is located on a side of the electron blocking unit close to the anode layer, and the orthographic projection of the electron blocking unit on the anode layer overlaps with the orthographic projection of the green light-emitting unit on the anode layer; the hole mobility of the electron blocking unit is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs, and / or, the hole mobility of the hole transport layer is greater than or equal to 10 -5 cm 2 / Vs and less than or equal to 10 -4 cm 2 / Vs.

12. A display device, characterized in that: A display panel comprising any one of claims 1 to 11.

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