Display panel and display device

Abstract

The invention relates to a display panel and a display device. The display panel comprises a substrate, a thin film transistor layer, a pixel definition layer and a light-emitting function layer. The pixel definition layer comprises a plurality of first dams and a plurality of second dams, the first dams are arranged in the first direction, the second dams are arranged in the second direction, the first dams and the second dams intersect to define a plurality of pixel openings arranged in an array, and a light-emitting device is correspondingly arranged in each pixel opening; the first dam body is made of the hydrophobic material, so that ink in the pixel opening can be prevented from overflowing; moreover, a plurality of first bulges are patterned on the surfaces, used for limiting the pixel openings, of the first dam bodies, and the plurality of first bulges are combined with a hydrophobic material, so that a lotus leaf effect can be generated on the surfaces of the first dam bodies, the hydrophobic performance is further improved, and the ink can be uniformly spread.

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] At present, inkjet printing technology has been widely used in the production of display devices. Taking the production of the organic light-emitting layer of OLED devices as an example, PDL (Pixel-determained Layer) is set on the substrate, and a plurality of grooves arranged in an array are formed on the pixel definition layer using photolithography technology. The grooves are filled with ink using inkjet printing technology. After the ink is cured, the organic light-emitting layer of the OLED device is formed.

[0003] In order to ensure that the ink between adjacent grooves does not overflow laterally, the material of the pixel definition layer needs to have a high hydrophobicity. Usually, after the grooves are formed using photolithography technology, UV (ultraviolet) cleaning or Plasma (plasma) cleaning is used to clean the residue in the grooves. Although this can ensure that the ink is evenly spread in the grooves, it will reduce the hydrophobicity of the inner wall of the groove. Summary of the invention

[0004] The embodiments of the present application provide a display panel and a display device, which can increase the hydrophobicity so that more printed ink is deposited at the bottom of the pixel opening and spread evenly.

[0005] In order to achieve the above object, according to a first aspect of the present application, a display panel is provided, comprising:

[0006] substrate;

[0007] A thin film transistor layer is disposed on one side of the substrate;

[0008] a pixel definition layer, the pixel definition layer being arranged on a side of the thin film transistor layer away from the substrate, the pixel definition layer comprising a plurality of first dams and a plurality of second dams, the first dams being arranged along a first direction, the second dams being arranged along a second direction, the plurality of first dams and the plurality of second dams intersecting to define a plurality of pixel openings arranged in an array;

[0009] A light-emitting functional layer, wherein the light-emitting functional layer includes a plurality of light-emitting devices, and each of the light-emitting devices is correspondingly arranged in one of the pixel openings;

[0010] The first dam includes a first dam body and a plurality of first protrusions, the plurality of first protrusions are at least arranged on a side surface of the first dam body, and the material of the first dam body includes a hydrophobic material.

[0011] In one embodiment, the first dam has a first end facing away from the thin film transistor layer, and a hydrophobic region is formed on a side of the first dam near the first end;

[0012] A plurality of the first protrusions are arranged on the side surface of the first dam body and located in the hydrophobic area.

[0013] In one embodiment, a plurality of the first protrusions are disposed on the side surface and the top surface of the first dam.

[0014] In one embodiment, the surface roughness of the first bank is less than 100 nm.

[0015] In one embodiment, in the first direction, the plurality of first protrusions include a plurality of rows of first protrusion groups arranged side by side and spaced apart, and each row of the first protrusion group includes a plurality of first protrusions arranged side by side and spaced apart in a height direction of the first dam body.

[0016] In one embodiment, the positions of the first protrusions on two adjacent rows of the first protrusion groups correspond to each other.

[0017] In one embodiment, the first protrusions on two adjacent rows of the first protrusion groups are staggered.

[0018] In one embodiment, the light emitting device includes a light emitting coating deposited within the pixel opening;

[0019] Wherein, in the height direction of the first dam, the height difference between the highest point of the edge of the luminescent coating adjacent to the first dam and the center point of the luminescent coating is set to 0≤H≤5nm.

[0020] In one embodiment, the contact angle between the luminescent coating and the side surface of the first dam is set to 65° to 70°.

[0021] According to a second aspect of the present application, a display device is provided, comprising the above-mentioned display panel.

[0022] In the display panel of the embodiment of the present application, a plurality of first dams and a plurality of second dams of the pixel definition layer cross-define a plurality of pixel openings, and a light-emitting device is correspondingly arranged in each pixel opening; it is known that inkjet printing technology is usually used to fill ink in the pixel opening, and a light-emitting coating of the light-emitting device is formed when the ink is solidified; by setting the material of the first dam body to a hydrophobic material, the ink in the pixel opening can be prevented from overflowing; and, at least a plurality of first protrusions are set on the side of the first dam body, and the plurality of first protrusions are combined with the hydrophobic material, so that a lotus effect can be generated on the surface of the first dam body, further increasing the hydrophobic performance, and then when printing ink in the pixel opening, the ink hanging on the wall can be reduced, so that the ink can be deposited more at the bottom of the pixel opening, thus, not only the amount of ink retained can be increased, but also the ink can be spread evenly.

[0023] Other features and advantages of the present application will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0025] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same figure numbers represent the same parts in the following description.

[0026] Figure 1 A film layer diagram of a display panel in the prior art;

[0027] Figure 2 A first film layer diagram of a display panel provided in an embodiment of the present application;

[0028] Figure 3 A second film layer diagram of a display panel provided in an embodiment of the present application;

[0029] Figure 4 A third film layer diagram of a display panel provided in an embodiment of the present application;

[0030] Figure 5 A first arrangement diagram of the first protrusions provided in an embodiment of the present application;

[0031] Figure 6 A second arrangement diagram of the first protrusions provided in an embodiment of the present application;

[0032] Figure 7aA flow chart of a display panel (providing a driving substrate) provided in an embodiment of the present application;

[0033] Figure 7b A flow chart of a display panel (making a photoresist layer) provided in an embodiment of the present application;

[0034] Figure 7c A flow chart of a display panel (making a pixel definition layer) provided in an embodiment of the present application;

[0035] Figure 7d A flow chart of a display panel (making a first protrusion) provided in an embodiment of the present application;

[0036] Figure 7e A flow chart of a display panel (cleaning) provided in an embodiment of the present application;

[0037] Figure 7f A flow chart of a display panel (filling ink) provided in an embodiment of the present application;

[0038] Figure 8 A plan view schematic diagram of a pixel definition layer provided in an embodiment of the present application. DETAILED DESCRIPTION

[0039] 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.

[0040] The present application provides a display panel 100, which includes a substrate 1, a thin film transistor layer 2, a pixel definition layer 3 and a light-emitting function layer 4; the thin film transistor layer 2 is arranged on one side of the substrate 1; the pixel definition layer 3 is arranged on the side of the thin film transistor layer 2 away from the substrate 1, the pixel definition layer 3 includes a plurality of first dams 31 and a plurality of second dams 32, the first dams 31 are arranged along a first direction F1, the second dams 32 are arranged along a second direction F2, and the plurality of first dams 31 and the plurality of second dams 32 cross to define a plurality of pixel openings 33 arranged in an array; the light-emitting function layer 4 includes a plurality of light-emitting devices 41, each of the light-emitting devices 41 is correspondingly arranged in one of the pixel openings 33; wherein the first dam 31 includes a first dam body 311 and a plurality of first protrusions 312, the plurality of first protrusions 312 are at least arranged on the side of the first dam body 311, and the material of the first dam body 311 includes a hydrophobic material.

[0041] In the display panel 100 of the embodiment of the present application, the plurality of first dams 31 and the plurality of second dams 32 of the pixel definition layer 3 cross-define a plurality of pixel openings 33 arranged in an array, and a light-emitting device 41 is correspondingly arranged in each of the pixel openings 33; it is known that inkjet printing technology is usually used to fill the pixel openings 33 with ink, and a light-emitting coating 411 of the light-emitting device 41 is formed when the ink is solidified; by setting the material of the pixel definition layer 3 to a hydrophobic material, the ink in the pixel openings 33 can be prevented from overflowing.

[0042] In the prior art, after the pixel opening 33' is formed on the pixel definition layer 3' by photolithography, material residues remain in the pixel opening 33'. In order to ensure uniform spreading of the ink, it is necessary to use UV (ultraviolet) cleaning or Plasma (plasma) cleaning to clean the residues in the pixel opening 33'. Although it is convenient for the ink to spread at the bottom of the pixel opening 33', cleaning the residues will reduce the hydrophobicity of the surface of the first dam 31', so that the ink sticks to the wall seriously and cannot be smoothly deposited to the bottom of the pixel opening 33', thereby making the ink film thickness uneven. Please refer to Figure 1 In the height direction F3' of the first dam 31', the highest point of the edge of the ink layer 411' adjacent to the first dam 31' is at half the position of the first dam 31', but the height difference between the highest point and the lowest point of the ink layer 411' is close to 700nm.

[0043] However, in this application, please refer to Figures 2 to 4 A plurality of first protrusions 312 are provided at least on the side surface 311a of the first dam body 311. The plurality of first protrusions 312 are combined with the hydrophobic material of the first dam body 311, so that a lotus effect can be produced on the surface of the first dam body 311, further increasing the hydrophobic performance. When printing ink in the pixel opening 33, the ink hanging on the wall can be reduced, so that more ink can be deposited at the bottom of the pixel opening 33. In this way, not only the amount of ink retained can be increased, but also the ink can be spread evenly.

[0044] It can be known that the use of a hydrophobic material to make the first dam body 311, on the one hand, helps the ink deposition in the pixel opening 33, ensuring that the ink deposition in each pixel opening 33 is uniform, and on the other hand, it can prevent the ink from diffusing to the adjacent pixel openings 33, avoiding the problem of ink mixing in adjacent pixel openings 33. The present application does not make any specific restrictions on the material of the first dam body 311. A main category of hydrophobic materials is fluorine-containing materials, because the presence of fluorine atoms makes the surface energy of the material very low, so that it has good hydrophobicity and oleophobicity. For example, polytetrafluoroethylene (PTFE) is a common hydrophobic material. In addition, other types of organic polymers may also be hydrophobic, such as certain types of polyesters, polyimides, etc.

[0045] In the present application, after the pixel opening 33 is formed on the pixel definition layer 3 by photolithography, a plurality of the first protrusions 312 are formed on the surface of the first dam 311 by oxygen ashing; O2-Ashing uses oxygen plasma to etch the photoresist. In the O2-Ashing process, oxygen is introduced into a reaction chamber, where it is excited into a plasma state by radio frequency (RF) energy. The free radicals (mainly oxygen free radicals) in this plasma react chemically with the photoresist, oxidizing it into volatile byproducts (such as carbon dioxide and water), which are then pumped away. The photoresist is removed because it is "ashed" into a gas.

[0046] Taking "the hydrophobic material is set as a fluorine-containing material" as an example, the first dam body 311 with hydrophobic properties is made of fluorine-containing material; when multiple first protrusions 312 are formed on the surface of the first dam body 311 using O2-Ashing, since O2-Ashing can evenly remove material from all directions, the etching degree can be adjusted by controlling parameters. While forming the first protrusion 312, at least the fluorine-containing material on the top of the first protrusion 312 can be retained. In this way, the formed first protrusion 312 itself also has hydrophobicity. At the same time, the concave-convex structure formed by the multiple first protrusions 312 can produce a lotus effect on the surface of the first dam body 311, thereby further increasing the hydrophobic performance.

[0047] The present application does not impose any specific limitation on the location of the first protrusion 312 .

[0048] See also Figure 2In the first embodiment of the present application, the first dam body 311 has a first end 311c away from the thin film transistor layer 2, and a hydrophobic area 311d is formed on the side 311a of the first dam body 311 near the first end 311c; a plurality of first protrusions 312 are arranged on the side 311a of the first dam body 311 and located in the hydrophobic area 311d. In this embodiment, a plurality of first protrusions 312 are arranged on the upper half of the side 311a. When printing ink in the pixel opening 33, since the upper half of the side 311a has a higher hydrophobicity, the ink can be spread as much as possible on the bottom of the pixel opening 33, so that the ink can be spread evenly.

[0049] See also Figure 3 In the second embodiment of the present application, a plurality of the first protrusions 312 are arranged on the side 311a of the first dam body 311, and the plurality of the first protrusions 312 cover the entire side 311a of the first dam body 311; when printing ink in the pixel opening 33, since the side 311a of the entire first dam body 311 has a high hydrophobicity, the ink can be spread over the bottom of the pixel opening 33 as much as possible, so that the ink can be further spread evenly.

[0050] See also Figure 4 In the third embodiment of the present application, a plurality of the first protrusions 312 are arranged on the side surface 311a and the top surface 311b of the first dam body 311; when printing ink in the pixel opening 33, since the surface of the entire first dam body 311 has a high hydrophobicity, the ink can be spread as much as possible on the bottom of the pixel opening 33, thereby further making the ink spread evenly.

[0051] Following the above embodiment, the present application does not impose any specific restrictions on the arrangement of the first protrusions 312. In the first direction F1, the plurality of first protrusions 312 include a plurality of rows of first protrusion groups arranged side by side and spaced apart, and each row of the first protrusion group includes a plurality of first protrusions 312 arranged side by side and spaced apart in the height direction F3 of the first dam body 311. In this way, the plurality of first protrusions 312 are arranged in a certain regular pattern, which can simplify the formation process of the first protrusions 312. Also, please refer to Figure 5 In one embodiment of the present application, the first protrusions 312 on two adjacent rows of the first protrusion groups correspond in position. Figure 6 In another embodiment of the present application, the first protrusions 312 on two adjacent rows of the first protrusion groups are staggered; the staggered first protrusions 312 can further increase the hydrophobicity of the surface of the first dam body 311.

[0052] It can be known that providing a plurality of first protrusions 312 on the side surface 311a and the top surface 311b of the first dam body 311 will increase the surface roughness of the first dam 31 as a whole. However, as the surface roughness of the first dam 31 increases, when printing ink in the pixel opening, the ink will hang on the surface of the first dam 31, so that the ink cannot be smoothly deposited on the bottom of the pixel opening 33. By setting the surface roughness of the first dam 31 to be less than 100nm, the ink hanging on the wall can be reduced, so that more ink can be deposited on the bottom of the pixel opening 33. In this way, not only the amount of ink retained can be increased, but also the ink can be spread evenly.

[0053] The present application does not impose any specific restriction on the shape of the first protrusion 312; the shape of the first protrusion 312 is set to be one of a hemispherical, a truncated cone and a cone; by setting the shape of the first protrusion 312 to be one of a hemispherical, a truncated cone and a cone, the end of the first protrusion 312 can be in point contact with the ink, thereby reducing the ink hanging on the wall, so that more ink can be deposited at the bottom of the pixel opening 33, thus not only increasing the amount of ink retained, but also making the ink spread evenly.

[0054] It can be known that at least the side surface 311a of the first dam body 311 is provided with a plurality of the first protrusions 312. The plurality of the first protrusions 312 combined with the hydrophobic material of the first dam body 311 enable the surface of the first dam body 311 to produce a lotus effect, thereby further increasing the hydrophobic performance. In other words, the plurality of the first protrusions 312 are equivalent to the concave-convex structure on the surface of the lotus leaf; the lotus effect is affected by the surface tension of the liquid and the contact angle and surface roughness of the parent material; taking water and lotus leaves as an example, the surface tension of water is 73mN / m, and in the concave-convex structure on the surface of the lotus leaf, the spacing between adjacent protrusions is set to 1um; in order to ensure that the plurality of the first protrusions 312 can produce the lotus effect, please refer to Figure 5 and Figure 6 , assuming that the surface tension of ink is 1 / 10 of that of water, the distance H2 between adjacent first protrusions 312 is set to 90nm~110nm; and the orthographic projection diameter D of the first protrusion 312 formed on the first dam body 311 is set to 90nm~110nm.

[0055] It can be known that inkjet printing technology is usually used to fill ink in the pixel opening 33, and when the ink is cured, the luminescent coating 411 of the light-emitting device 41 is formed; in the height direction F3 of the first dam body 311, the height difference H1 between the highest point of the edge of the luminescent coating 411 adjacent to the first dam body 311 and the center point of the luminescent coating 411 is set to 0≤H1≤5nm.

[0056] Furthermore, since a plurality of first protrusions 312 are provided on the side 311a of the first dam body 311, the plurality of first protrusions 312 combined with the hydrophobic material of the first dam body 311 enable the surface of the first dam body 311 to produce a lotus effect; when ink is filled in the pixel opening 33 using inkjet printing technology, the ink layer is evenly spread at the bottom of the pixel opening 33; since the plurality of first protrusions 312 increase the hydrophobicity of the side 311a of the first dam body 311, the contact angle between the ink layer and the side 311a of the first dam body 311 becomes larger, and the contact angle between the ink layer and the side 311a before curing is set to 70-75°; after curing, the ink layer forms the luminescent coating, and the contact angle ɑ between the luminescent coating and the side 311a is set to 65°-70°.

[0057] Based on the structure of the display panel above, please refer to Figure 7a to Figure 7f , the present application also provides a method for preparing a display panel.

[0058] S10: providing a driving substrate 1; S20: coating a negative photoresist solution on the driving substrate 1 to form a photoresist layer 5; S30: exposing the photoresist layer 5 using a mask plate, and developing the photoresist layer 5 using an alkaline developer, thereby forming the pixel definition layer 3, wherein the pixel definition layer 3 includes a plurality of first dam bodies 311 crisscrossed, and the plurality of first dam bodies 311 define a plurality of pixel openings 33; S40: etching the surface of the first dam body 311 using O2-Ashing to form a plurality of first protrusions 312; S50: cleaning the residue in the pixel opening 33 using UV (ultraviolet) cleaning or Plasma (plasma) cleaning, and after cleaning, using an air knife to air-dry the surface moisture of the driving substrate 1 and the pixel definition layer 3;

[0059] S60: performing high temperature curing on the pixel definition layer 3; S70: using inkjet printing technology to fill ink into the pixel opening 33 and curing the ink.

[0060] It should be noted that the present application does not impose any specific restrictions on the structure of the second dam 32. The second dam 32 can be conventionally configured; the second dam 32 can also be configured with a concave-convex structure.

[0061] See also Figure 8In one embodiment of the present application, the second dam 32 includes a second dam body 321 and a plurality of second protrusions 322, the plurality of second protrusions 322 are at least arranged on the side 321a of the second dam body 321, and the material of the second dam body 321 includes a hydrophilic material. By providing a plurality of second protrusions 322, the hydrophobicity of the surface of the second dam 32 can be improved, which can not only prevent the ink from diffusing to the adjacent pixel openings 33 and avoid the problem of ink mixing in the adjacent pixel openings 33; but also reduce the ink hanging on the wall, so that the ink can be deposited more at the bottom of the pixel opening 33, thereby increasing the amount of ink remaining and making the ink spread evenly.

[0062] Since a plurality of second protrusions 322 are provided on the side 321a of the second dam body 321, the hydrophobicity of the side 321a of the second dam body 321 is improved; when ink is filled in the pixel opening 33 using inkjet printing technology, the ink layer is evenly spread at the bottom of the pixel opening 33; at this time, the contact angle between the ink layer and the side 321a of the second dam body 321 becomes larger, and the contact angle between the ink layer and the side 321a before curing is set to 20 to 30°; after curing, the ink layer forms the luminescent coating, and the contact angle between the luminescent coating and the side 311a is set to 5° to 20°.

[0063] In a second aspect, the embodiments of the present application further provide a display device. The display device includes a display panel 100. It should be noted that the display panel 100 is set as the above-mentioned display panel 100, that is, the display panel 100 includes all the technical features of the above-mentioned display panel 100, and the display device includes all the embodiments of the above-mentioned display panel 100, and also has all the technical effects of the above-mentioned embodiments, which will not be repeated here one by one.

[0064] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0065] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0066] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0067] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A display panel, characterized in that: include: substrate; A thin film transistor layer is disposed on one side of the substrate; a pixel definition layer, the pixel definition layer being arranged on a side of the thin film transistor layer away from the substrate, the pixel definition layer comprising a plurality of first dams and a plurality of second dams, the first dams being arranged along a first direction, the second dams being arranged along a second direction, the plurality of first dams and the plurality of second dams intersecting to define a plurality of pixel openings arranged in an array; A light-emitting functional layer, wherein the light-emitting functional layer includes a plurality of light-emitting devices, and each of the light-emitting devices is correspondingly arranged in one of the pixel openings; The first dam includes a first dam body and a plurality of first protrusions, the plurality of first protrusions are at least arranged on a side surface of the first dam body, and the material of the first dam body includes a hydrophobic material.

2. The display panel according to claim 1, wherein: The first dam has a first end facing away from the thin film transistor layer, and a hydrophobic area is formed on a side of the first dam near the first end; A plurality of the first protrusions are arranged on the side surface of the first dam body and located in the hydrophobic area.

3. The display panel according to claim 1, wherein: A plurality of the first protrusions are arranged on the side surface and the top surface of the first dam body.

4. The display panel according to claim 1, wherein: The surface roughness of the first bank is less than 100 nm.

5. The display panel according to claim 1, wherein: In the first direction, the plurality of first protrusions include a plurality of rows of first protrusion groups arranged side by side and at intervals, and each row of the first protrusion group includes a plurality of first protrusions arranged side by side and at intervals in the height direction of the first dam body.

6. The display panel according to claim 5, wherein: The first protrusions on the first protrusion groups in two adjacent rows correspond to each other in position.

7. The display panel according to claim 5, wherein: The first protrusions on two adjacent rows of the first protrusion groups are staggered.

8. The display panel according to claim 1, wherein: The light emitting device includes a light emitting coating deposited within the pixel opening; Wherein, in the height direction of the first dam, a height difference H between the highest point of the edge of the luminescent coating adjacent to the first dam and the center point of the luminescent coating is set to 0≤H≤5nm.

9. The display panel according to claim 8, wherein: The contact angle between the luminescent coating and the side surface of the first dam is set to 65° to 70°.

10. A display device, characterized in that: Comprising a display panel as described in any one of claims 1-9.

Images