Display panel and display apparatus

Abstract

Disclosed in the embodiments of the present application are a display panel and a display apparatus. In the display panel of the present application, an electron blocking layer is omitted in at least one of the spacings between a third light-emitting unit and a first hole transport layer and between a second light-emitting unit and the first hole transport layer, and the first hole transport layer is thickened, thereby preventing a reduction in the luminous efficiency of light-emitting devices that correspond to the third light-emitting unit and / or the second light-emitting unit, and also saving on masks and simplifying process steps.

Description

Display panel and display device 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] In related technologies, a stacked device refers to a device structure that uses a charge generation layer (CGL) to connect multiple light-emitting units. The CGL contains at least a P-CGL layer with high hole mobility and an N-CGL layer with high electron mobility. Stacked devices have the characteristics of high efficiency and high brightness life, but the complexity of the device structure and the difficulty of the production process are significantly increased. Compared with the single-layer device, the double-layer stacked device constructed by directly stacking single-layer devices has 11 new film layers. Among them, each layer of the device corresponding to each color (R / G / B) is provided with an electron blocking layer to improve the luminous efficiency of various colors of light. Compared with the current single-layer device, multiple common layer and light-emitting layer metal masks are required. The device structure and process complexity of this double-layer stacked device are greatly increased, and the production cost is also greatly increased. SUMMARY OF THE INVENTION

[0003] The embodiments of the present application provide a display panel and a display device, which can save part of the electron blocking layer without reducing the luminous efficiency of the display panel, thereby saving the mask and related process steps.

[0004] In one aspect, an embodiment of the present application provides a display panel, comprising:

[0005] substrate;

[0006] a first conductive layer disposed on the substrate, the first conductive layer comprising a plurality of first electrodes, a plurality of second electrodes, and a plurality of third electrodes;

[0007] a first hole transport layer, disposed on the first conductive layer;

[0008] A first electron blocking layer is provided on the first hole transport layer, the first electron blocking layer comprising: a first electron blocking portion provided corresponding to the first electrode;

[0009] a first light-emitting layer, disposed on the first electron blocking layer, the first light-emitting layer comprising: a first light-emitting unit disposed corresponding to the first electrode, a second light-emitting unit disposed corresponding to the second electrode, and a third light-emitting unit disposed corresponding to the third electrode;

[0010] a charge generating layer, disposed on the first light-emitting layer;

[0011] a second hole transport layer, disposed on the charge generation layer, wherein the thickness of the second hole transport layer is less than that of the first hole transport layer;

[0012] a second electron blocking layer disposed on the second hole transport layer, the second electron blocking layer comprising: a fourth electron blocking portion disposed corresponding to the first electrode, a fifth electron blocking portion disposed corresponding to the second electrode, and a sixth electron blocking portion disposed corresponding to the third electrode;

[0013] a second light-emitting layer, disposed on the second electron blocking layer, the second light-emitting layer comprising: a fourth light-emitting unit disposed corresponding to the first electrode, a fifth light-emitting unit disposed corresponding to the second electrode, and a sixth light-emitting unit disposed corresponding to the third electrode;

[0014] a second conductive layer, disposed on the second light-emitting layer;

[0015] Wherein, a surface of the first hole transport layer away from the substrate is in direct contact with at least one of the second light-emitting unit and the third light-emitting unit.

[0016] On the other hand, an embodiment of the present application further provides a display device, which includes the display panel as described in any one of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] FIG1 is a schematic structural diagram of a display panel provided in an embodiment of the present application;

[0018] FIG2 is another schematic structural diagram of a display panel provided in an embodiment of the present application;

[0019] FIG3 is another structural schematic diagram of a display panel provided in an embodiment of the present application;

[0020] FIG4 is a schematic structural diagram of Comparative Example 1 in a comparative simulation experiment;

[0021] FIG5 is a schematic structural diagram of Comparative Example 2 in a comparative simulation experiment;

[0022] FIG6 is a schematic structural diagram of Comparative Example 3 in a comparative simulation experiment;

[0023] FIG7 is a schematic structural diagram of Comparative Example 4 in a comparative simulation experiment. Modes for Carrying Out the Invention

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present application 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, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application and are not used to limit the present application. In the present application, unless otherwise specified, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inside" and "outside" refer to the outline of the device; the terms "first", "second", "third", etc. are used only as labels and do not impose numerical requirements or establish an order.

[0025] The embodiments of the present application provide a display panel and a display device, which are described in detail below. It should be noted that the order of description of the following embodiments does not limit the preferred order of the embodiments.

[0026] An embodiment of the present application provides a display panel, comprising:

[0027] substrate;

[0028] a first conductive layer disposed on the substrate, the first conductive layer comprising a plurality of first electrodes, a plurality of second electrodes, and a plurality of third electrodes;

[0029] a first hole transport layer, disposed on the first conductive layer;

[0030] A first electron blocking layer is provided on the first hole transport layer, the first electron blocking layer comprising: a first electron blocking portion provided corresponding to the first electrode;

[0031] a first light-emitting layer, disposed on the first electron blocking layer, the first light-emitting layer comprising: a first light-emitting unit disposed corresponding to the first electrode, a second light-emitting unit disposed corresponding to the second electrode, and a third light-emitting unit disposed corresponding to the third electrode;

[0032] a charge generation layer, disposed on the first light-emitting layer;

[0033] a second hole transport layer, disposed on the charge generation layer, wherein the thickness of the second hole transport layer is less than that of the first hole transport layer;

[0034] a second electron blocking layer disposed on the second hole transport layer, the second electron blocking layer comprising: a fourth electron blocking portion disposed corresponding to the first electrode, a fifth electron blocking portion disposed corresponding to the second electrode, and a sixth electron blocking portion disposed corresponding to the third electrode;

[0035] a second light-emitting layer, disposed on the second electron blocking layer, the second light-emitting layer comprising: a fourth light-emitting unit disposed corresponding to the first electrode, a fifth light-emitting unit disposed corresponding to the second electrode, and a sixth light-emitting unit disposed corresponding to the third electrode;

[0036] a second conductive layer, disposed on the second light-emitting layer;

[0037] Wherein, a surface of the first hole transport layer on a side away from the substrate is in direct contact with at least one of the second light-emitting unit and the third light-emitting unit.

[0038] Optionally, in some embodiments of the present application, the area of ​​the first light-emitting unit is larger than the area of ​​the second light-emitting unit and the area of ​​the third light-emitting unit.

[0039] Optionally, in some embodiments of the present application, the first light-emitting unit and the fourth light-emitting unit both display a first color, the second light-emitting unit and the fifth light-emitting unit both display a second color, the third light-emitting unit and the sixth light-emitting unit both display a third color, and the first color, the second color, and the third color are all different.

[0040] Optionally, in some embodiments of the present application, a third electron blocking portion is provided between the third light-emitting unit and the first hole transport layer, and the second light-emitting unit directly contacts a surface of the first hole transport layer away from the substrate.

[0041] Optionally, in some embodiments of the present application, the third light-emitting unit and the sixth light-emitting unit are configured to emit red light, the second light-emitting unit and the fifth unit are configured to emit green light, and the thickness of the fifth electron blocking portion is greater than or equal to 10 nanometers.

[0042] Optionally, in some embodiments of the present application, a second electron blocking portion is provided between the second light-emitting unit and the first hole transport layer, and the third light-emitting unit directly contacts a surface of the first hole transport layer away from the substrate.

[0043] Optionally, in some embodiments of the present application, the third light-emitting unit and the sixth light-emitting unit are configured to emit red light, the second light-emitting unit and the fifth unit are configured to emit green light, and the thickness of the sixth electron blocking portion is greater than or equal to 50 nanometers.

[0044] Optionally, in some embodiments of the present application, the third light-emitting unit and the second light-emitting unit both directly contact a surface of the first hole transport layer away from the substrate.

[0045] Optionally, in some embodiments of the present application, the third light-emitting unit and the sixth light-emitting unit are configured to emit red light, the second light-emitting unit and the fifth unit are configured to emit green light, the thickness of the sixth electron blocking portion is greater than or equal to 50 nanometers, and the thickness of the fifth electron blocking portion is greater than or equal to 10 nanometers.

[0046] Optionally, in some embodiments of the present application, the thickness of the first hole transport layer is between 30 nanometers and 35 nanometers, and the thickness of the second hole transport layer is between 20 nanometers and 25 nanometers.

[0047] Optionally, in some embodiments of the present application, the charge generation layer includes an N-type charge generation layer and a P-type charge generation layer sequentially arranged on the first light-emitting layer, the P-type charge generation layer includes an organic material with hole transport capability and a first doping material, the first doping material is selected from at least one of a metal oxide and an organic material with electron-withdrawing properties, and the weight percentage of the first doping material in the P-type charge generation layer is between 0.1% and 20%.

[0048] Optionally, in some embodiments of the present application, the weight percentage of the first doping material in the P-type charge generation layer is between 3% and 13%, and the thickness of the P-type charge generation layer is between 5 nanometers and 50 nanometers.

[0049] Optionally, in some embodiments of the present application, the N-type charge generation layer includes an organic material with electron transport capability and a second doping material, the second doping material is selected from at least one of a metal material and a metal salt material, and the weight percentage of the second doping material in the N-type charge generation layer is between 0.1% and 20%.

[0050] Optionally, in some embodiments of the present application, the weight percentage of the second doping material in the N-type charge generation layer is between 0.1% and 10%, and the thickness of the N-type charge generation layer is between 5 nanometers and 50 nanometers.

[0051] Optionally, in some embodiments of the present application, the first light-emitting unit and the fourth light-emitting unit are both configured to emit blue light.

[0052] Optionally, in some embodiments of the present application, the display panel further includes a hole injection layer, a first hole blocking layer, a first electron transport layer, a second hole blocking layer, a second electron transport layer and an electron injection layer;

[0053] The hole injection layer covers the first conductive layer, the first hole transport layer covers the hole injection layer, the first hole blocking layer covers the first light-emitting layer, the first electron transport layer is arranged on the side of the charge generating layer close to the substrate and covers the first hole blocking layer, the second hole blocking layer covers the second light-emitting layer, the second electron transport layer covers the second hole blocking layer, and the electron injection layer is arranged on the side of the second conductive layer close to the substrate and covers the second electron transport layer.

[0054] An embodiment of the present application further provides a display device, which includes the display panel as described in any one of the above embodiments.

[0055] The display panel of the embodiment of the present application saves an electron blocking layer in at least one of the spaces between the third light-emitting unit and the first hole transport layer and between the second light-emitting unit and the first hole transport layer, and thickens the first hole transport layer to avoid a reduction in the luminous efficiency of the light-emitting device corresponding to the second light-emitting unit and / or the third light-emitting unit, thereby saving a mask and simplifying the process steps.

[0056] Referring to Figure 1, an embodiment of the present application provides a display panel 100, which includes a substrate 11, a first conductive layer 121, a second conductive layer 122, a first hole transport layer 131, a second hole transport layer 132, a first light-emitting layer 141, a second light-emitting layer 142, a charge generation layer 15, a first electron blocking layer 161 and a second electron blocking layer 162.

[0057] The first conductive layer 121 is disposed on the substrate 11 . The first conductive layer 121 includes a plurality of first electrodes 12 a , a plurality of second electrodes 12 b , and a plurality of third electrodes 12 c . The first hole transport layer 131 is disposed on the first conductive layer 121 .

[0058] The first electron blocking layer 161 is disposed on the first hole transport layer 131. The first electron blocking layer 161 includes a first electron blocking portion 16a disposed corresponding to the first electrode 12a.

[0059] The first light emitting layer 141 is disposed on the first electron blocking layer 161. The first light emitting layer 141 includes a first light emitting unit 14a disposed corresponding to the first electrode 121, a second light emitting unit 14b disposed corresponding to the second electrode 12b, and a third light emitting unit 14c disposed corresponding to the third electrode 12c.

[0060] The charge generation layer 15 is provided on the first light emitting layer 141. The second hole transport layer 132 is provided on the charge generation layer 15. The thickness of the second hole transport layer 132 is smaller than the thickness of the first hole transport layer 131.

[0061] The second electron blocking layer 162 is disposed on the second hole transport layer 132. The second electron blocking layer 162 includes a fourth electron blocking portion 16d corresponding to the first electrode 12a, a fifth electron blocking portion 16e corresponding to the second electrode 12b, and a sixth electron blocking portion 16f corresponding to the third electrode 12c.

[0062] The second light emitting layer 142 is disposed on the second electron blocking layer 162. The second light emitting layer 142 includes a fourth light emitting unit 14d disposed corresponding to the first electrode 12a, a fifth light emitting unit 14e disposed corresponding to the second electrode 12b, and a sixth light emitting unit 14f disposed corresponding to the third electrode 12c.

[0063] The second conductive layer 122 is provided on the second light emitting layer 142 .

[0064] The first hole transport layer 131 has a surface on one side away from the substrate 11 that is in direct contact with at least one of the second light emitting unit 14 b and the third light emitting unit 14 c .

[0065] The display panel 100 of the embodiment of the present application saves an electron blocking layer in at least one of the spaces between the third light-emitting unit 14c and the first hole transport layer 131 and between the second light-emitting unit 14b and the first hole transport layer 131, and thickens the first hole transport layer 131 to avoid a reduction in the luminous efficiency of the light-emitting device corresponding to the second light-emitting unit 14b and / or the third light-emitting unit 14c, thereby saving a mask and simplifying the process steps.

[0066] Optionally, the first conductive layer 121 is an anode layer, and the second conductive layer 122 is a cathode layer.

[0067] Optionally, the substrate 11 is a driving substrate having a driving circuit, which includes a thin film transistor and a signal line, etc. One electrode is correspondingly connected to one thin film transistor.

[0068] Optionally, the materials of the first to sixth light-emitting units 14a to 14f are each organic light-emitting materials.

[0069] The first light-emitting area is the area where the first and fourth light-emitting units 14a and 14d, which emit the same color of light, are stacked. The third light-emitting area is the area where the third and sixth light-emitting units 14c and 14f, which also emit the same color of light, are stacked. The second light-emitting area is the area where the second and fifth light-emitting units 14b and 14e, which emit the same color of light, are stacked. The first, second, and third light-emitting areas each emit different colors of light. The third light-emitting area is correspondingly provided with the third electrode 12c, and the second light-emitting area is correspondingly provided with the second electrode 12b. In other words, one electrode drives each light-emitting area.

[0070] That is, the first light emitting unit 14a and the fourth light emitting unit 14d both display a first color, the second light emitting unit 14b and the fifth light emitting unit 14e both display a second color, and the third light emitting unit 14c and the sixth light emitting unit 14f both display a third color. The first color, the second color, and the third color are all different.

[0071] Optionally, in one embodiment, the first light-emitting area emits blue light. In addition, when the third light-emitting area emits red light, the second light-emitting area emits green light; and when the third light-emitting area emits green light, the second light-emitting area emits red light.

[0072] Optionally, the area of ​​the first light emitting unit 14a is larger than the area of ​​the second light emitting unit 14b and the area of ​​the third light emitting unit 14c. Since the first light emitting unit 14a emits blue light, the area of ​​the first light emitting unit 14a is set to increase the light emitting brightness of the first light emitting unit 14a.

[0073] Optionally, the charge generation layer 15 includes an N-type charge generation layer 15a and a P-type charge generation layer 15b stacked in sequence. The first hole transport layer 131, the second hole transport layer 132, the N-type charge generation layer 15a, the P-type charge generation layer 15b, and the second conductive layer 17 are common layers. That is, the first hole transport layer 131, the second hole transport layer 132, the N-type charge generation layer 15a, the P-type charge generation layer 15b, and the second conductive layer 17 are disposed entirely on the display area of ​​the display panel 100.

[0074] In addition, the charge generation layer 15 is a charge generation composite structure having charge generation capability. It is understood that the charge generation composite structure is connected and disposed between two adjacent light-emitting units to form a stacked organic light-emitting device. Each light-emitting unit includes at least a hole transport layer and a light-emitting layer.

[0075] Optionally, in one embodiment, the display panel 100 further includes a hole injection layer 18 , a first hole blocking layer 191 , a first electron transport layer 201 , a second hole blocking layer 192 , a second electron transport layer 202 and an electron injection layer 21 .

[0076] The hole injection layer 18 covers the first conductive layer 121. The first hole transport layer 131 covers the hole injection layer 18. The first hole blocking layer 191 covers the first light-emitting layer 141. The first electron transport layer 201 is provided on the side of the charge generation layer 15a closer to the substrate 11 and covers the first hole blocking layer 191. The second hole blocking layer 192 covers the second light-emitting layer 142. The second electron transport layer 202 covers the second hole blocking layer 192. The electron injection layer 21 is provided on the side of the second conductive layer 17 closer to the substrate 11 and covers the second electron transport layer 202.

[0077] Optionally, the hole injection layer 18 , the first hole blocking layer 191 , the first electron transport layer 201 , the second hole blocking layer 192 , the second electron transport layer 202 and the electron injection layer 23 are also common layers and are also entirely disposed in the display area of ​​the display panel 100 .

[0078] Optionally, in this embodiment, the P-type charge generation layer 15b includes an organic material having hole transport capability and a first doping material, wherein the first doping material is selected from at least one of a metal oxide and an organic material having electron-withdrawing properties.

[0079] The weight percentage of the first doping material in the P-type charge generation layer 15b is between 0.1% and 20%; for example, it can be 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19% or 20%, etc.

[0080] It is understood that the P-type charge generation layer 15b is used to achieve charge separation and transfer holes generated by charge separation to the sixth light-emitting unit 14f, the fifth light-emitting unit 14e, and the fourth light-emitting unit 146. The first doping material is used to reduce the charge separation barrier and thus reduce the voltage.

[0081] If the amount of the first doping material doped is too small, the purpose of lowering the charge separation barrier cannot be achieved, and if it is too much, the risk of film leakage will increase; therefore, the weight percentage of the first doping material in the P-type charge generation layer 15b is between 0.1% and 20%, which can achieve the purpose of lowering the charge separation barrier while reducing the risk of film leakage.

[0082] Furthermore, in one embodiment, the first dopant material accounts for a weight percentage of the P-type charge generation layer 15b ranging from 3% to 13%. The thickness of the P-type charge generation layer 15b ranges from 5 nanometers to 50 nanometers, such as 5 nanometers, 10 nanometers, 20 nanometers, 25 nanometers, 30 nanometers, 35 nanometers, 40 nanometers, 45 nanometers, or 50 nanometers.

[0083] It is understood that if the P-type charge generation layer 15b is too thick, it will increase the risk of film leakage, while if it is too thin, it will affect device performance. Therefore, to further reduce the risk of leakage in the P-type charge generation layer 15b, lower the charge separation barrier, and ensure the performance of the light-emitting device, the weight percentage of the first dopant material in the P-type charge generation layer 15b is selected to be between 3% and 13%. The thickness of the P-type charge generation layer 15b is between 5 nanometers and 50 nanometers.

[0084] Optionally, the first doping material may include at least one of MoO3, WO3, V2O5, Fe3O4, dipyrazino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexanitrile (HATCN), 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone (F4TCNQ), and cyanomethane derivatives.

[0085] Optionally, in one embodiment, the N-type charge generation layer 15a includes an organic material having electron transport capability and a second doping material, wherein the second doping material is selected from at least one of a metal material and a metal salt material.

[0086] The weight percentage of the second doping material in the N-type charge generation layer 15 a is between 0.1% and 20%.

[0087] The weight percentage of the second doping material in the N-type charge generation layer 15a is between 0.1% and 20%; for example, it can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19% or 20%, etc.

[0088] It is understood that the N-type charge generation layer 15a is used to achieve charge separation and transfer the electrons generated by charge separation to the third light-emitting unit 14c, the second light-emitting unit 14b, and the first light-emitting unit 145. The second doping material is used to reduce the charge separation barrier and thus reduce the voltage.

[0089] If the amount of the second doping material is too small, the purpose of lowering the charge separation barrier cannot be achieved, and if it is too much, the risk of film leakage will increase; therefore, the weight percentage of the second doping material in the N-type charge generation layer 15a is between 0.1% and 20%, which can achieve the purpose of lowering the charge separation barrier while reducing the risk of film leakage.

[0090] Furthermore, in one embodiment, the weight percentage of the second dopant material in the N-type charge generation layer 15a is between 0.1% and 10%. The thickness of the N-type charge generation layer 15a is between 5 nanometers and 50 nanometers, for example, 5 nanometers, 10 nanometers, 20 nanometers, 25 nanometers, 30 nanometers, 35 nanometers, 40 nanometers, 45 nanometers, or 50 nanometers.

[0091] It is understood that if the N-type charge generation layer 15a is too thick, it will increase the risk of film leakage, while if it is too thin, it will affect device performance. Therefore, to further reduce the risk of leakage in the N-type charge generation layer 15a, lower the charge separation barrier, and ensure the performance of the light-emitting device, the weight percentage of the second dopant material in the N-type charge generation layer 15a is selected to be between 0.1% and 10%. The thickness of the N-type charge generation layer 15a is between 5 nanometers and 50 nanometers.

[0092] Optionally, the second doping material may include at least one of elemental lithium, sodium, potassium, cesium, magnesium, calcium, strontium, barium, ytterbium, lithium fluoride, sodium fluoride, lithium carbonate, cesium carbonate, and lithium nitride.

[0093] 1 , a second electron blocking portion 16b is provided between the second light emitting unit 14b and the first hole transport layer 131. The third light emitting unit 14c directly contacts the surface of the first hole transport layer 131 away from the substrate 11.

[0094] 1 , the third light-emitting unit 14c and the sixth light-emitting unit 14f are configured to emit red light, and the second light-emitting unit 14b and the fifth light-emitting unit 14e are configured to emit green light. This eliminates the need for an electron blocking layer between the third light-emitting unit 14c and the first hole transport layer 131.

[0095] It can be understood that when the electron blocking layer between the third light-emitting unit 14c and the first hole transport layer 131 is saved, the position of the third light-emitting unit 14c will be lowered, so that the light-emitting position of the third light-emitting unit 14c is shifted. Therefore, by increasing the thickness of the first hole transport layer 131 to compensate for the increase in the light-emitting position of the third light-emitting unit 14c, the risk of the light-emitting position of the third light-emitting unit 14c being shifted is reduced, so as to maintain or improve the light-emitting efficiency of the third light-emitting unit 14c.

[0096] In addition, when the electron blocking layer between the third light-emitting unit 14c and the first hole transport layer 131 is saved, the electron-hole balance at the third light-emitting unit 14c deviates during light emission, causing the luminous efficiency of the third light-emitting unit 14c to decrease. Therefore, by increasing the thickness of the first hole transport layer 131 to compensate for the improvement of the electron-hole balance at the third light-emitting unit 14c during light emission, the risk of deviation of the electron-hole balance at the third light-emitting unit 14c during light emission is reduced, thereby maintaining or improving the luminous efficiency of the third light-emitting unit 14c.

[0097] Optionally, in one embodiment, the thickness of the sixth electron blocking portion 16f is greater than or equal to 50 nanometers, for example, 50 nanometers, 55 nanometers, 60 nanometers, 65 nanometers, 70 nanometers, 75 nanometers, 80 nanometers, 85 nanometers, or 90 nanometers.

[0098] It is understandable that when the electron blocking layer is omitted between the third light-emitting unit 14c and the first hole transport layer 131, the luminescence chromaticity of the third light-emitting region will decrease. Therefore, by thickening the sixth electron blocking portion 16f of the third light-emitting region to compensate for the optical microcavity length of the red light-emitting device, the risk of chromaticity degradation in the third light-emitting region is reduced.

[0099] Furthermore, in order to better maintain the standard of the luminous color chromaticity of the third luminescent area, the thickness of the sixth electron blocking portion 16f is between 70 nanometers and 80 nanometers, for example, it can be 70 nanometers, 71 nanometers, 72 nanometers, 73 nanometers, 74 nanometers, 75 nanometers, 76 nanometers, 77 nanometers, 78 nanometers, 79 nanometers or 80 nanometers, etc.

[0100] 2 , in one embodiment, a third electron blocking portion 16c is provided between the third light emitting unit 14c and the first hole transport layer 131 . The second light emitting unit 14b directly contacts the surface of the first hole transport layer 131 away from the substrate 11 .

[0101] The third light emitting unit 14c and the sixth light emitting unit 14f are configured to emit red light, and the second light emitting unit 14b and the fifth light emitting unit 14e are configured to emit green light, that is, the electron blocking layer between the second light emitting unit 14b and the first hole transport layer 131 is omitted.

[0102] It can be understood that when the electron blocking layer between the second light-emitting unit 14b and the first hole transport layer 131 is saved, the position of the second light-emitting unit 14b will be lowered, so that the light-emitting position of the second light-emitting unit 14b is shifted. Therefore, by increasing the thickness of the first hole transport layer 131 to compensate for the increase in the light-emitting position of the second light-emitting unit 14b, the risk of the light-emitting position of the second light-emitting unit 14b being shifted is reduced, so as to maintain or improve the light-emitting efficiency of the second light-emitting unit 14b.

[0103] In addition, when the electron blocking layer between the second light-emitting unit 14b and the first hole transport layer 131 is saved, the electron-hole balance at the second light-emitting unit 14b deviates during light emission, causing the luminous efficiency of the second light-emitting unit 14b to decrease. Therefore, by increasing the thickness of the first hole transport layer 131 to compensate for the improvement of the electron-hole balance at the second light-emitting unit 14b during light emission, the risk of deviation of the electron-hole balance at the second light-emitting unit 14b during light emission is reduced, thereby maintaining or improving the luminous efficiency of the second light-emitting unit 14b.

[0104] Optionally, in one embodiment, the thickness of the fifth electron blocking portion 16e is greater than or equal to 10 nanometers, for example, 10 nanometers, 15 nanometers, 20 nanometers, 25 nanometers, 30 nanometers, 35 nanometers, 40 nanometers, 45 nanometers or 50 nanometers.

[0105] It is understandable that when the electron blocking layer is omitted between the second light-emitting unit 14b and the first hole transport layer 131, the luminescence chromaticity of the second light-emitting region will decrease. Therefore, by thickening the fifth electron blocking portion 16e of the second light-emitting region to compensate for the optical microcavity length of the green light-emitting device, the risk of chromaticity degradation in the second light-emitting region is reduced.

[0106] Furthermore, in order to better maintain the standard of the luminescent color chromaticity of the second luminescent region, the thickness of the fifth electron blocking portion 16e is between 10 nm and 30 nm, for example, 10 nm, 15 nm, 20 nm, 25 nm or 30 nm.

[0107] Optionally, referring to FIG. 3 , in one embodiment, the third light-emitting unit 14 c and the second light-emitting unit 14 b both directly contact the surface of the first hole transport layer 131 on a side away from the substrate 11 .

[0108] In the embodiment shown in FIG3 , the third light-emitting unit 14 c and the sixth light-emitting unit 14 f are configured to emit red light, while the second light-emitting unit 14 b and the fifth light-emitting unit 14 e are configured to emit green light. This eliminates the need for an electron blocking layer between the third light-emitting unit 14 c and the first hole transport layer 131, and also eliminates the need for an electron blocking layer between the second light-emitting unit 14 b and the first hole transport layer 131.

[0109] It can be understood that when the electron blocking layer between the third light-emitting unit 14c and the first hole transport layer 131 and between the second light-emitting unit 14b and the first hole transport layer 131 is saved, the position of the third light-emitting unit 14c and the second light-emitting unit 14b will be lowered, so that the light-emitting positions of the third light-emitting unit 14c and the second light-emitting unit 14b are offset. Therefore, by increasing the thickness of the first hole transport layer 131 to compensate for the increase in the light-emitting position of the third light-emitting unit 14c and the second light-emitting unit 14b, the risk of the light-emitting position of the third light-emitting unit 14c and the second light-emitting unit 14b being offset is reduced, so as to maintain or improve the light-emitting efficiency of the second light-emitting unit 14b.

[0110] In addition, when the electron blocking layer between the third light-emitting unit 14c and the second light-emitting unit 14b and the first hole transport layer 131 is saved, the electron-hole balance at the third light-emitting unit 14c and the second light-emitting unit 14b deviates during light emission, causing the luminous efficiency of the third light-emitting unit 14c and the second light-emitting unit 14b to decrease. Therefore, by increasing the thickness of the first hole transport layer 131 to compensate for the improvement of the electron-hole balance at the third light-emitting unit 14c and the second light-emitting unit 14b during light emission, the risk of deviation in the electron-hole balance at the third light-emitting unit 14c and the second light-emitting unit 14b during light emission is reduced, thereby maintaining or improving the luminous efficiency of the third light-emitting unit 14c and the second light-emitting unit 14b.

[0111] Optionally, in one embodiment, the thickness of the fifth electron blocking portion 16e is greater than or equal to 10 nanometers, such as 10 nanometers, 15 nanometers, 20 nanometers, 25 nanometers, 30 nanometers, 35 nanometers, 40 nanometers, 45 nanometers, or 50 nanometers. The thickness of the sixth electron blocking portion 16f is greater than or equal to 50 nanometers, such as 50 nanometers, 55 nanometers, 60 nanometers, 65 nanometers, 70 nanometers, 75 nanometers, 80 nanometers, 85 nanometers, or 90 nanometers.

[0112] It is understandable that when the electron blocking layer is omitted between the third light-emitting unit 14c and the first hole transport layer 131, and between the second light-emitting unit 14b and the first hole transport layer 131, the luminescence chromaticity of the third and second light-emitting regions will decrease. Therefore, by thickening the sixth electron blocking portion 16f of the third light-emitting region and the fifth electron blocking portion 16e of the second light-emitting region to compensate for the optical microcavity length of the red and green light-emitting devices, the risk of chromaticity degradation in the third and second light-emitting regions is reduced.

[0113] Furthermore, in order to better maintain the standards of the luminous color chromaticity of the third light-emitting area and the second light-emitting area, the thickness of the sixth electron blocking portion 16f is between 70 nanometers and 80 nanometers, for example, it can be 70 nanometers, 71 nanometers, 72 nanometers, 73 nanometers, 74 nanometers, 75 nanometers, 76 nanometers, 77 nanometers, 78 nanometers, 79 nanometers or 80 nanometers, etc.; the thickness of the fifth electron blocking portion 16e is between 10 nanometers and 30 nanometers, for example, it can be 10 nanometers, 15 nanometers, 20 nanometers, 25 nanometers or 30 nanometers, etc.

[0114] Optionally, in one embodiment, the thickness of the first hole transport layer 131 is between 30 nm and 35 nm, such as 30 nm, 31 nm, 32 nm, 33 nm, 34 nm, and 35 nm. The thickness of the second hole transport layer 132 is between 20 nm and 25 nm, such as 20 nm, 21 nm, 22 nm, 23 nm, 24 nm, and 25 nm.

[0115] Among them, it can be understood that the thickening of the first hole transport layer 131 will cause the light-emitting positions of the third light-emitting unit 14c to the fifth light-emitting unit 14e to rise. Therefore, in order to avoid the light-emitting positions of the sixth light-emitting unit 14f and the fifth light-emitting unit 14e from deviating or rising too much, the thickness of the second hole transport layer 132 can be thinned to reduce the risk of deviation of the light-emitting positions of the sixth light-emitting unit 14f and the fifth light-emitting unit 14e, thereby improving the luminous efficiency of the red light device and / or the green light device.

[0116] In addition, by adjusting the thickness of the first hole transport layer 131 and the second hole transport layer 132 , the injection and transport of electrons and holes can be adjusted, that is, the carrier balance can be adjusted to improve the luminous efficiency of the light-emitting device.

[0117] In addition, the present application designs a comparative simulation experiment, which includes Comparative Example 1, Comparative Example 2, Comparative Example 3, Comparative Example 4, Example 1, and Example 2. Comparative Example 1 corresponds to light-emitting device 1 (as shown in FIG4 ), Comparative Example 2 corresponds to light-emitting device 2 (as shown in FIG5 ), Comparative Example 3 corresponds to light-emitting device 3 (as shown in FIG6 ), Comparative Example 4 corresponds to light-emitting device 4 (as shown in FIG7 ), Example 1 corresponds to light-emitting device 5, and Example 2 corresponds to light-emitting device 6.

[0118] Among them, in the light-emitting device 1 of comparative example 1, the light-emitting device 1 includes an anode layer D1, a hole injection layer D2, a first hole transport layer D31, a first electron blocking layer, a first light-emitting layer, a first hole blocking layer D61, a first electron transport layer D71, an N-type charge generation layer D81, a P-type charge generation layer D82, a second hole transport layer D32, a second electron blocking layer, a second light-emitting layer, a second hole blocking layer D62, a second electron transport layer D72, an electron injection layer D9 and a cathode layer D10, which are stacked in sequence.

[0119] The first electron blocking layer includes a first electron blocking portion D41, a second electron blocking portion D42, and a third electron blocking portion D43. The second electron blocking layer includes a fourth electron blocking portion D44 corresponding to the first electron blocking portion D41, a fifth electron blocking portion D45 corresponding to the second electron blocking portion D42, and a sixth electron blocking portion D46 corresponding to the third electron blocking portion D43.

[0120] The first light-emitting layer includes a first red light-emitting cell D51 corresponding to the first electron blocking portion D41, a first green light-emitting cell D52 corresponding to the second electron blocking portion D42, and a first blue light-emitting cell D53 corresponding to the third electron blocking portion D43. The second light-emitting layer includes a second red light-emitting cell D54 corresponding to the fourth electron blocking portion D44, a second green light-emitting cell D55 corresponding to the fifth electron blocking portion D45, and a second blue light-emitting cell D56 corresponding to the sixth electron blocking portion D46.

[0121] The anode layer D1 includes a plurality of independent anodes, and one anode corresponds to two stacked light-emitting units.

[0122] It should be noted that the thickness of the hole transport layer 1 of the light-emitting device 1 corresponding to Comparative Example 1 is 25 nanometers, and the thickness of the hole transport layer 2 is 30 nanometers. Compared with Comparative Example 1, the light-emitting device 2 corresponding to Comparative Example 2 only reduces the red electron blocking layer 1 and increases the thickness of the red electron blocking layer 2; compared with Comparative Example 1, the light-emitting device 3 corresponding to Comparative Example 3 only reduces the green electron blocking layer 1 and increases the thickness of the green electron blocking layer 2; compared with Comparative Example 1, the light-emitting device 4 corresponding to Comparative Example 4 only reduces the red electron blocking layer 1 and the green electron blocking layer 1, and increases the thickness of the red electron blocking layer 2 and the green electron blocking layer 2. Compared with Comparative Example 4, the light-emitting device 5 corresponding to Example 1 has only the hole transport layer 2 thinned by 5 nanometers, and the hole transport layer 1 thickened by 5 nanometers. Compared with Comparative Example 4, the light-emitting device 6 corresponding to Example 2 has only the hole transport layer 2 thinned by 10 nanometers, and the hole transport layer 1 thickened by 10 nanometers.

[0123] Among them, Example 1 and Example 2 are the embodiments shown in Figure 3 of this application.

[0124] Based on the above six light-emitting devices, the luminous efficiency of the red, green and blue devices corresponding to each light-emitting device was measured, as shown in the following table:

[0125] Differentiated device Red light luminous efficiency Green light luminous efficiency Blue light luminous efficiency Comparative example 1 Light-emitting device 1 100% 100% 100% Comparative example 2 Light-emitting device 2 97% 100% 100% Comparative example 3 Light-emitting device 3 100% 98% 100% Comparative example 4 Light-emitting device 4 97% 98% 100% Example 1 Light-emitting device 5 104% 102% 100% Example 2 Light-emitting device 6 105% 103% 101%

[0126] According to the results of Comparative Examples 2 to 4 in the above table, even if the thickness of the electron blocking layer is reduced, the luminous efficiency will still be reduced by only compensating the thickness of the electron blocking layer 2 of the corresponding color.

[0127] The results of Examples 1 and 2 show that by increasing the hole transport layer 1 (first hole transport layer 131) and thinning the hole transport layer 2 (second hole transport layer 132), the luminous efficiency of red and green light devices can be improved without the electron blocking layer 1. The improvement in luminous efficiency of the red device is greater than that of the green device.

[0128] In addition, according to the results of Example 1 and Example 2, when the thickness of the hole transport layer 1 increases to a certain extent, the blue light emitting efficiency will also be improved.

[0129] An embodiment of the present application further provides a display device, which includes the display panel as described in any one of the above embodiments.

[0130] It should be noted that the structure of the display panel of the display device is similar to or the same as the structure of the display panel 100 of any of the above embodiments, and therefore will not be described in detail here.

[0131] Optionally, the display device can be a smartphone, a tablet personal computer, a mobile phone, a video phone, an e-book reader, a desktop PC, a laptop PC, a netbook computer, a workstation, a server, a personal digital assistant, a portable multimedia player, an MP3 player, a television, a mobile medical machine, a camera, a game console, a digital camera, a car navigation system, an electronic billboard, an ATM or at least one of a wearable device, a VR device, and an AR device.

[0132] The display panel of the display device of the embodiment of the present application saves an electron blocking layer in at least one of the space between the third light-emitting unit and the first hole transport layer and between the second light-emitting unit and the first hole transport layer, and thickens the first hole transport layer to avoid a decrease in the luminous efficiency of the light-emitting device corresponding to the second light-emitting unit and / or the third light-emitting unit, thereby saving a mask and simplifying the process steps.

[0133] The above is a detailed introduction to a display panel and a display device provided in the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for those skilled in the art, based on the ideas of the present application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A display panel, comprising: a substrate; a first conductive layer disposed on the substrate, the first conductive layer including a plurality of first electrodes, a plurality of second electrodes, and a plurality of third electrodes; a first hole transport layer disposed on the first conductive layer; a first electron blocking layer disposed on the first hole transport layer, the first electron blocking layer including: a first electron blocking portion corresponding to the first electrode; a first light-emitting layer disposed on the first electron blocking layer, the first light-emitting layer including: a first light-emitting unit corresponding to the first electrode, a second light-emitting unit corresponding to the second electrode, and a third light-emitting unit corresponding to the third electrode; a charge generation layer disposed on the first light-emitting layer; a second hole transport layer disposed on the charge generation layer, the thickness of the second hole transport layer being less than the thickness of the first hole transport layer; a second electron blocking layer disposed on the second hole transport layer, the second electron blocking layer including: a fourth electron blocking portion corresponding to the first electrode, a fifth electron blocking portion corresponding to the second electrode, and a sixth electron blocking portion corresponding to the third electrode; a second light-emitting layer disposed on the second electron blocking layer, the second light-emitting layer including: a fourth light-emitting unit corresponding to the first electrode, a fifth light-emitting unit corresponding to the second electrode, and a sixth light-emitting unit corresponding to the third electrode; a second conductive layer disposed on the second light-emitting layer; wherein, one surface of the first hole transport layer away from the substrate is in direct contact with at least one of the second light-emitting unit and the third light-emitting unit.

2. The display panel according to claim 1, wherein, The area of the first light-emitting unit is larger than the areas of the second light-emitting unit and the third light-emitting unit.

3. The display panel according to claim 2, wherein, The first light-emitting unit and the fourth light-emitting unit both display a first color, the second light-emitting unit and the fifth light-emitting unit both display a second color, the third light-emitting unit and the sixth light-emitting unit both display a third color, and the first color, the second color, and the third color are all different.

4. The display panel according to claim 2, wherein, A third electron blocking portion is disposed between the third light-emitting unit and the first hole transport layer, and the second light-emitting unit is in direct contact with one surface of the first hole transport layer away from the substrate.

5. The display panel according to claim 3, wherein, The third light-emitting unit and the sixth light-emitting unit are configured to emit red light, the second light-emitting unit and the fifth light-emitting unit are configured to emit green light, and the thickness of the fifth electron blocking portion is greater than or equal to 10 nanometers.

6. The display panel according to claim 2, wherein, A second electron blocking portion is disposed between the second light-emitting unit and the first hole transport layer, and the third light-emitting unit is in direct contact with one surface of the first hole transport layer away from the substrate.

7. The display panel according to claim 6, wherein, The third light-emitting unit and the sixth light-emitting unit are configured to emit red light, the second light-emitting unit and the fifth unit are configured to emit green light, and the thickness of the sixth electron blocking portion is greater than or equal to 50 nanometers.

8. The display panel according to claim 2, wherein, Both the third light-emitting unit and the second light-emitting unit are in direct contact with one surface of the first hole transport layer away from the substrate.

9. The display panel according to claim 8, wherein, The third light-emitting unit and the sixth light-emitting unit are configured to emit red light, the second light-emitting unit and the fifth light-emitting unit are configured to emit green light, the thickness of the sixth electron blocking portion is greater than or equal to 50 nanometers, and the thickness of the fifth electron blocking portion is greater than or equal to 10 nanometers.

10. The display panel according to claim 1, wherein, The thickness of the first hole transport layer is between 30 nanometers and 35 nanometers, and the thickness of the second hole transport layer is between 20 nanometers and 25 nanometers.

11. The display panel according to claim 1, wherein, The charge generation layer includes an N-type charge generation layer and a P-type charge generation layer sequentially disposed on the first light-emitting layer. The P-type charge generation layer includes an organic material having hole transport ability and a first doping material. The first doping material is selected from at least one of metal oxides and organic materials having an electron-withdrawing property. The weight percentage of the first doping material in the P-type charge generation layer is between 0.1% and 20%.

12. The display panel according to claim 11, wherein, The weight percentage of the first doping material in the P-type charge generation layer is between 3% and 13%, and the thickness of the P-type charge generation layer is between 5 nanometers and 50 nanometers.

13. The display panel according to claim 11, wherein, The N-type charge generation layer includes an organic material having electron transport ability and a second doping material. The second doping material is selected from at least one of metal materials and metal salt materials. The weight percentage of the second doping material in the N-type charge generation layer is between 0.1% and 20%.

14. The display panel according to claim 13, wherein, The weight percentage of the second doping material in the N-type charge generation layer is between 0.1% and 10%, and the thickness of the N-type charge generation layer is between 5 nanometers and 50 nanometers.

15. A display device, wherein, Including a display panel, the display panel includes: A substrate; A first conductive layer disposed on the substrate, the first conductive layer includes a plurality of first electrodes, a plurality of second electrodes, and a plurality of third electrodes; A first hole transport layer disposed on the first conductive layer; A first electron blocking layer disposed on the first hole transport layer, the first electron blocking layer includes: a first electron blocking portion corresponding to the first electrode; A first light-emitting layer disposed on the first electron blocking layer, the first light-emitting layer includes: a first light-emitting unit corresponding to the first electrode, a second light-emitting unit corresponding to the second electrode, and a third light-emitting unit corresponding to the third electrode; A charge generation layer disposed on the first light-emitting layer; A second hole transport layer disposed on the charge generation layer, the thickness of the second hole transport layer is less than the thickness of the first hole transport layer; A second electron blocking layer disposed on the second hole transport layer, the second electron blocking layer includes: a fourth electron blocking portion corresponding to the first electrode, a fifth electron blocking portion corresponding to the second electrode, and a sixth electron blocking portion corresponding to the third electrode; A second light-emitting layer disposed on the second electron blocking layer, the second light-emitting layer includes: a fourth light-emitting unit corresponding to the first electrode, a fifth light-emitting unit corresponding to the second electrode, and a sixth light-emitting unit corresponding to the third electrode; A second conductive layer disposed on the second light-emitting layer; Wherein, one side surface of the first hole transport layer away from the substrate is in direct contact with at least one of the second light-emitting unit and the third light-emitting unit.

16. The display device according to claim 15, wherein, The area of the first light-emitting unit is larger than the areas of the second light-emitting unit and the third light-emitting unit.

17. The display device according to claim 16, wherein, The first light-emitting unit and the fourth light-emitting unit both display a first color, the second light-emitting unit and the fifth light-emitting unit both display a second color, the third light-emitting unit and the sixth light-emitting unit both display a third color, and the first color, the second color, and the third color are all different.

18. The display device according to claim 16, wherein, A third electron blocking portion is provided between the third light-emitting unit and the first hole transport layer, and the second light-emitting unit is in direct contact with one side surface of the first hole transport layer away from the substrate.

19. The display device according to claim 17, wherein, The third light-emitting unit and the sixth light-emitting unit are configured to emit red light, the second light-emitting unit and the fifth light-emitting unit are configured to emit green light, and the thickness of the fifth electron blocking portion is greater than or equal to 10 nanometers.

20. The display device according to claim 16, wherein, A second electron blocking portion is provided between the second light-emitting unit and the first hole transport layer, and the third light-emitting unit is in direct contact with one side surface of the first hole transport layer away from the substrate.

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