CN113990903A

CN113990903A - Display substrate and display panel

Info

Publication number: CN113990903A
Application number: CN202111244411.1A
Authority: CN
Inventors: 贾文斌
Original assignee: BOE Technology Group Co Ltd; Hefei BOE Zhuoyin Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Hefei BOE Zhuoyin Technology Co Ltd
Priority date: 2021-10-25
Filing date: 2021-10-25
Publication date: 2022-01-28

Abstract

The invention provides a display substrate and a display panel, relates to the technical field of display, and aims to improve the film forming uniformity of the display panel so as to prolong the service life of a product and improve the quality of the product. A display substrate, comprising: a substrate, and a pixel defining layer disposed on the substrate; the pixel defining layer comprises a first defining sublayer and a second defining sublayer; the first delimiting sublayer comprises a first delimiting part and a plurality of openings arranged in an array, and the openings are configured to be defined and formed by the first delimiting part; the second defining sublayer comprises a plurality of parallel second defining parts arranged on the side of the first defining part far away from the substrate; the first defining part has lyophilic property, and the second defining part has lyophobic property; the display substrate further comprises a plurality of light-emitting units which are arranged in an array mode, each light-emitting unit comprises an organic light-emitting functional layer, and the organic light-emitting functional layers are arranged in the openings; the same organic light-emitting functional layer is arranged in the plurality of openings in the area between two adjacent second defining parts.

Description

Display substrate and display panel

Technical Field

The invention relates to the technical field of display, in particular to a display substrate and a display panel.

Background

As a novel Light Emitting device, an OLED (Organic Light-Emitting Diode) has the advantages of self-luminescence, fast response, wide viewing angle, high brightness, bright color, lightness, thinness and the like, compared with liquid crystal display, and has a wide application prospect in the display field.

At present, the organic functional layer of the OLED is formed by adopting the processes of ink-jet printing and the like, along with the popularization of high-resolution products, the printing precision and hardware conditions of the ink-jet printing are limited, the film forming uniformity of an OLED display panel is poor, and poor display such as Suji Mura and the like is easily generated, so that the service life and the quality of the product are reduced.

Disclosure of Invention

Embodiments of the present invention provide a display substrate and a display panel, so as to improve film formation uniformity of the display panel, and further improve product life and quality.

In order to achieve the above purpose, the embodiment of the invention adopts the following technical scheme:

in one aspect, a display substrate is provided, including: a substrate, and a pixel defining layer disposed on the substrate;

the pixel defining layer comprises a first defining sublayer and a second defining sublayer; the first delimiting sublayer comprises a first delimiting part and a plurality of openings arranged in an array, and the openings are configured to be defined and formed by the first delimiting part; the second defining sublayer comprises a plurality of parallel second defining portions disposed on a side of the first defining portion remote from the substrate; the first defining portion has lyophilic property, and the second defining portion has lyophobic property;

the display substrate further comprises a plurality of light-emitting units arranged in an array, each light-emitting unit comprises an organic light-emitting functional layer, and the organic light-emitting functional layers are arranged in the openings;

the same organic light-emitting functional layer is arranged in a plurality of the openings in the area between two adjacent second defined parts.

Optionally, a ratio of a thickness of the first defining portion in a direction perpendicular to the substrate to a thickness of the second defining portion in the direction perpendicular to the substrate ranges from 1/5 to 1/3.

Optionally, the light emitting unit further includes a first electrode disposed on a side of the organic light emitting functional layer close to the substrate;

wherein a contact angle of the first boundary portion is less than or equal to a contact angle of the first electrode.

Optionally, a ratio of a thickness of the first defining portion in a direction perpendicular to the substrate to a thickness of the first electrode in the direction perpendicular to the substrate is in a range of 1 to 6.

Optionally, the second defining part is arranged along a first direction;

an orthogonal projection of the second defining portion on the substrate overlaps an orthogonal projection of a portion of the first defining portion disposed in the first direction on the substrate.

Optionally, the second defining portion is a bar.

Optionally, a shape of a cross section of the second defining portion in a direction perpendicular to the substrate includes a trapezoid, a triangle, or a semicircle.

Optionally, the material of the first and second defining portions includes a resin or an inorganic material.

Optionally, the plurality of light emitting units are divided into a red light emitting unit, a green light emitting unit and a blue light emitting unit;

the light-emitting units arranged along the first direction are light-emitting units of the same color, and the red light-emitting units, the green light-emitting units and the blue light-emitting units are arranged along the second direction, wherein the first direction is the same as the direction of the second defining part, and the second direction is the same as the arrangement direction of the second defining parts.

In another aspect, a display panel is provided, which includes the display substrate.

An embodiment of the present invention provides a display substrate and a display panel, where the display substrate includes: a substrate, and a pixel defining layer disposed on the substrate; the pixel defining layer comprises a first defining sublayer and a second defining sublayer; the first delimiting sublayer comprises a first delimiting part and a plurality of openings arranged in an array, and the openings are configured to be defined and formed by the first delimiting part; the second defining sublayer comprises a plurality of parallel second defining portions disposed on a side of the first defining portion remote from the substrate; the first defining portion has lyophilic property, and the second defining portion has lyophobic property; the display substrate further comprises a plurality of light-emitting units arranged in an array, each light-emitting unit comprises an organic light-emitting functional layer, and the organic light-emitting functional layers are arranged in the openings; the same organic light-emitting functional layer is arranged in a plurality of the openings in the area between two adjacent second defined parts.

Therefore, when the organic light-emitting functional layer is formed by adopting an ink-jet printing process, the ink in the area between the two adjacent second defining parts circulates mutually, so that the ink flowing into the opening in the area is averaged, the difference of the ink volume in different openings in the area is reduced, the printing film forming uniformity is improved, and the service life and the quality of a product are improved.

The foregoing description is only an overview of the technical solutions of the present application, and the present application can be implemented according to the content of the description in order to make the technical means of the present application more clearly understood, and the following detailed description of the present application is given in order to make the above and other objects, features, and advantages of the present application more clearly understandable.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a display substrate according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a display substrate provided with ink droplets according to an embodiment of the present invention;

FIG. 3 is a schematic view of the structure of FIG. 2 showing the overflow of the ink drop;

FIG. 4 is a schematic structural diagram of another display substrate according to an embodiment of the present invention;

FIG. 5 is a cross-sectional view taken along direction EE of FIG. 4;

FIG. 6 is a schematic structural diagram of the pixel defining layer in FIG. 4;

FIG. 7 is a cross-sectional view taken along direction FF in FIG. 6;

FIG. 8 is a schematic structural diagram of the first defining sublayer of FIG. 6;

FIG. 9 is a schematic structural diagram of the second defining sublayer of FIG. 6;

FIG. 10 is a schematic structural diagram of another display substrate according to an embodiment of the present invention;

in FIG. 11, A is a schematic view of a contact angle of the second defining portion, and B is a schematic view of a contact angle of the first electrode;

in fig. 12, a is a test result chart in which the contact angle of the second boundary portion is larger than that of the first electrode, and B is a test result chart in which the contact angle of the second boundary portion is smaller than that of the first electrode.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the embodiments of the present invention, the terms "first", "second", and the like are used for distinguishing identical items or similar items having substantially the same functions and actions, and are used only for clearly describing technical solutions of the embodiments of the present invention, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features.

In the embodiments of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the embodiments of the present invention, the terms "upper", "lower", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the embodiment of the present invention, the lyophilic property and the lyophobic property are relative to the same liquid phase medium, for example, when the liquid phase medium is water, the lyophilic property and the lyophobic property are hydrophilic property and hydrophobic property; when the liquid medium is oil, the lyophilic and lyophobic properties are oleophilic and oleophobic properties.

The film forming method of OLED mainly includes evaporation process and solution process. At present, the evaporation process technology is applied to mass production, but the technology has expensive materials, low material utilization rate and high product development cost. The solution process OLED film forming method mainly includes inkjet printing, nozzle coating, spin coating, screen printing, etc.

Referring to fig. 1, a general inkjet printing process requires a Pixel Definition Layer (PDL)12 to be previously formed on an electrode 11 of a substrate 10 to define a precise flow of ink droplets into a designated R/G/B (red/green/blue) sub-pixel opening area C. With the popularization of high-resolution products (for example, 255ppi), the opening of the sub-pixel becomes smaller, so that the film forming uniformity in the sub-pixel is continuously reduced, thereby affecting the service life and the quality of the product. Furthermore, due to the hardware limitations of the printer head, each Nozzle (Nozzle) cannot ensure the volume of the ink droplet ejected into each sub-pixel opening to be consistent, and even though printing is performed by a mixing algorithm, poor display of Suji Mura and the like cannot be avoided. In addition, the higher the requirement of high-resolution products on printing precision, the higher the design requirement on the short side direction of the sub-pixels.

Based on the above, an embodiment of the present invention provides a display substrate, which is shown in fig. 4 and 5, and includes: a substrate 1, and a pixel defining layer 2 disposed on the substrate 1.

As shown in connection with fig. 6-9, the pixel defining layer 2 includes a first defining sublayer 21 and a second defining sublayer 22; the first delimiting sublayer 21 includes a first delimiting part 211 and a plurality of openings 212 arranged in an array, the openings being configured to be defined by the first delimiting part; the second defining sublayer 22 comprises a plurality of parallel second defining portions 221 arranged on a side of the first defining portion 211 remote from the substrate 1; the first defining portion has lyophilic property, and the second defining portion has lyophobic property.

The display substrate further includes a plurality of light emitting units arranged in an array, as shown in fig. 4-7, the light emitting units include an organic light emitting functional layer 30, and the organic light emitting functional layer 30 is disposed in the opening 212.

The same organic light-emitting functional layer is arranged in the plurality of openings in the area between two adjacent second defining parts.

The material of the substrate is not limited, and for example, a rigid material may be used, such as: glass; alternatively, flexible materials may also be used, such as: polyimide (PI).

Referring to fig. 4, the second defining portion (also called Line Bank)221 may be disposed along the first direction (OB direction shown in fig. 4), and the length of the second defining portion along the first direction is not limited herein; the second defining portion may be disposed to correspond to the first defining portion disposed in the first direction. Of course, the second defining portion may be disposed along the second direction (OA direction shown in fig. 4), which is not limited herein. Fig. 4 is a diagram illustrating the second defining portion along the first direction OB.

Referring to fig. 5, the light-emitting unit may further include a first electrode 4 and a second electrode (not shown in fig. 5), the first electrode 4 is disposed on a side of the organic light-emitting functional layer 30 close to the substrate 1, the second electrode is disposed on a side of the organic light-emitting functional layer far from the substrate, that is, the organic light-emitting functional layer is disposed between the first electrode and the second electrode, and different voltage signals are respectively input to the first electrode and the second electrode, so that an electric field is generated between the first electrode and the second electrode, and the organic light-emitting functional layer can emit light under the action of the electric field. Here, one of the first electrode and the second electrode may serve as an anode, and the other may serve as a cathode. Illustratively, the first electrode may be selected to be an anode and the second electrode may be selected to be a cathode.

In order to improve the light emitting efficiency, the organic light emitting function layer may include a Hole Injection Layer (HIL), an emission layer (EML), an Electron Transport Layer (ETL), and an Electron Injection Layer (EIL) which are stacked. In the case where the first electrode is an anode, a hole injection layer, a light-emitting layer, an electron transport layer, and an electron injection layer are sequentially stacked over the first electrode. Of course, the organic light emitting functional layer may also include other structures, which are not limited herein.

The display substrate may include light emitting units of the same emission color, for example: a red light emitting unit, a green light emitting unit, or a blue light emitting unit, thereby realizing a single color picture display. Alternatively, the display substrate may include light emitting units of a plurality of emission colors at the same time, for example: meanwhile, the LED display device comprises a red light-emitting unit, a green light-emitting unit and a blue light-emitting unit, thereby realizing color picture display.

If the same organic light emitting function layer is disposed in the plurality of openings located in the area between two adjacent second defining portions, it means that the light emitting units located in the area between two adjacent second defining portions are light emitting units of the same color, that is, the plurality of sub-pixels corresponding to the area between two adjacent second defining portions are sub-pixels of the same color, for example: an R (red) sub-pixel, a G (green) sub-pixel, or a B (blue) sub-pixel.

The principle of the effect of the display substrate of the present invention such as improvement in film formation uniformity will be described in detail below.

In the current inkjet printing process, referring to fig. 2, a printer prints ink along the long side of a sub-pixel P, and when there is a difference in volume between an ink droplet a (labeled 13 in fig. 2) and an ink droplet B (labeled 14 in fig. 2) (for example, the volume of the ink droplet a is larger than that of the ink droplet B), referring to fig. 3, the ink droplet a (labeled 13 in fig. 3) may overflow, thereby resulting in Suji Mura in the Y direction. Also, the higher the resolution of the display panel, the more serious the phenomenon of Mura. Meanwhile, as the resolution is increased, the Pitch (Pitch) between sub-pixels is decreased, so that the printing accuracy is required to be higher and higher, and color crosstalk and thin and dark lines are easily generated.

Taking an 8K display product with a resolution of 160PPI as an example, relevant parameters of the product are shown in tables 1-3, in table 1, referring to fig. 2, Sub Pitch is a length D0 of the Sub-Pixel P along the X direction, Pixel width is a width D1 of the Sub-Pixel P along the Y direction, and Bank width is a width D2 of the Pixel defining layer 12 between adjacent Sub-pixels P along the Y direction. In Table 2, Head is the volume of the ink in picoliters (pl); the droplet diameter D3 has units of micrometers (μm). Table 3 shows the impact accuracy D4 in microns (μm), where in table 3 the impact accuracy of the printer differs for printing different film layers, the impact accuracy for printing the hole transport layer (HTL layer) and the emissive layer (EML) is ± 8 μm, and the impact accuracy for printing the hole injection layer (HIL layer) is ± 12 μm.

TABLE 1

TABLE 2

Head(pl)	Droplet diameter D3(μm)
		4.85	21

TABLE 3

The allowed landing range and the ink droplet fluctuation range are explained below. The allowed impact range B is D1+ D2/X, where X is an intrinsic parameter, and may be 2 for example; referring to FIG. 2, D2/X represents the maximum deflection of an ink drop within which the drop can autonomously return into the opening. The ink droplet fluctuation range a is D3+ D4 × 2, and if B > a, printing is not problematic. For certain PPI products, B is fixed, so increasing printing capacity can only be achieved by reducing a, i.e. by reducing the droplet diameter D3 and increasing the landing accuracy D4, which puts higher demands on the printer.

How to reduce the fluctuation range A of ink drops (i.e. improve the landing accuracy) or improve the allowable landing range B of products is the key to the design of high-resolution products at present. The pixel defining layer of the display substrate comprises a first defining sublayer and a second defining sublayer, after deviation occurs in printing of a printer, for example, ink drops are printed on the pixel defining layer between adjacent openings arranged along the OA direction shown in FIG. 4, due to the arrangement of the second defining part 221, the ink drops can rapidly flow to other sub-pixel areas arranged along the OB direction along the second defining part, the probability that the ink drops flow to the adjacent sub-pixel areas arranged along the OA direction is greatly reduced, the X value is effectively reduced, the allowable impact range B is improved, the precision requirement on the printer is further reduced, and meanwhile, the color crosstalk and the thin dark lines of printing are reduced.

The application provides a display substrate, when adopting the ink jet printing technology to form organic light emitting function layer, the regional ink of two adjacent second demarcation portion circulates each other for the open-ended ink that flows into in this region is averaged, thereby reduces the difference of the interior ink volume of different openings in this region, and then has improved and has printed the membrane homogeneity, thereby improves product life and quality. Meanwhile, the precision requirement on the printer can be reduced, and the color crosstalk and the thin and dark line phenomenon of printing are reduced.

In addition, in the display substrate using the first and second defining sub-layers, the fluidity of the ink has an important influence on the final film forming effect, and the better the fluidity of the ink is, the higher the film forming uniformity is, and the better the final film forming effect is. In the display substrate, the first defining parts have lyophilic property, the second defining parts have lyophobic property, and the fluidity of ink in an area between two adjacent second defining parts can be greatly improved, so that the difference of ink volumes in different openings in the area is further reduced, the uniformity of a printed film is further improved, and a better film forming effect is finally realized.

Alternatively, referring to fig. 7, the ratio of the thickness H1 of the first defining part 211 in the direction perpendicular to the substrate 1 to the thickness H2 of the second defining part 221 in the direction perpendicular to the substrate 1 ranges from 1/5 to 1/3, and may be 1/5, 1/4, 4/15, 3/10, 1/3, and so on, for example.

The first defining portion has lyophilic properties and affinity for ink droplets; and the second defining portion has lyophobicity and repulsive force to the ink droplets. If the thickness of the first defining portion in the direction perpendicular to the substrate is greater than the thickness of the second defining portion in the direction perpendicular to the substrate, the fluidity of the ink is poor. Therefore, in order to improve the fluidity of the ink, the thickness of the first defining portion in the direction perpendicular to the substrate is smaller than the thickness of the second defining portion in the direction perpendicular to the substrate. In addition, in the case where the thickness of the first defining portion in the direction perpendicular to the substrate is smaller than the thickness of the second defining portion in the direction perpendicular to the substrate, if the ratio of the thickness of the first defining portion in the direction perpendicular to the substrate to the thickness of the second defining portion in the direction perpendicular to the substrate is too high, the ink flow is not facilitated. If the ratio of the thickness of the first defining portion in the direction perpendicular to the substrate to the thickness of the second defining portion in the direction perpendicular to the substrate is too small, it is indicated that the thickness of the first defining portion in the direction perpendicular to the substrate is too small, and/or the thickness of the second defining portion in the direction perpendicular to the substrate is too large. However, the first boundary portion has an excessively small thickness in the direction perpendicular to the substrate, which causes the following problems: in the prior art, the first defining part with smaller thickness is difficult to form by adopting organic resin; the first defining portion formed by the inorganic film and having a small thickness has a poor planarization effect, and the formed defining area has unevenness, a low material utilization rate, and a poor defining isolation effect. The second boundary portion has a problem of low material utilization rate due to an excessively large thickness in a direction perpendicular to the substrate. Therefore, it is important to set the thickness of the first defining portion in the direction perpendicular to the substrate and the thickness of the second defining portion in the direction perpendicular to the substrate reasonably. The thickness range of the first defining part along the direction vertical to the substrate can be 0.16-0.5 μm, the thickness range of the second defining part along the direction vertical to the substrate can be 0.8-1.5 μm, and the ratio range of the thickness of the first defining part along the direction vertical to the substrate to the thickness of the second defining part along the direction vertical to the substrate is 1/5-1/3, so that the fluidity of the ink can be ensured, the ink material can be fully utilized, and the production cost is reduced.

Alternatively, referring to fig. 5, the light emitting unit further includes a first electrode 4, the first electrode 4 is disposed on one side of the organic light emitting function layer 30 close to the substrate 1; wherein the contact angle of the first boundary portion is smaller than or equal to the contact angle of the first electrode.

The contact angle is an angle formed by two tangents of a gas-liquid interface and a solid-liquid interface at a solid-liquid-gas three-phase boundary point on the surface of a solid when a liquid drop is dropped on a horizontal plane of the solid to clamp a liquid phase. The contact angle can be determined by a related instrument. The contact angle of the first defining portion is α 1 shown in a of fig. 11, and the contact angle of the second defining portion is α 2 shown in B of fig. 11. Fig. 11 schematically shows only the contact angle of the first defining portion and the contact angle of the second defining portion, and does not limit the magnitude relationship between the two.

In the course of research, it was found that when the contact angle (e.g., 10 °) of the first defining portion is larger than the contact angle (e.g., 4 °) of the first electrode, the fluidity of the ink in the region between two adjacent second defining portions (e.g., the same-column sub-pixel region along the X direction shown in a diagram a in fig. 12) is significantly reduced, and the effect of the second defining portion is greatly reduced.

In order to ensure and improve the fluidity of the ink, the contact angle of the first boundary portion is smaller than or equal to the contact angle of the first electrode. Fig. 12 a is a test chart of the display substrate using a contact angle (10 °) of the first boundary portion larger than a contact angle (4 °) of the first electrode, and fig. 12B is a test chart of the display substrate using a contact angle (10 °) of the first boundary portion smaller than a contact angle of the first electrode. In fig. 12 a and B, the black area B is provided with transparent ink. In diagram B of fig. 12, the inks corresponding to the sub-pixels of the same column in the X direction are connected; in the diagram a of fig. 12, the inks corresponding to the sub-pixels in the same column along the X direction are not connected; comparing the graphs a and B of fig. 12, the ink fluidity of the graph B corresponding structure is much higher than that of the graph a corresponding structure.

The light-emitting unit may further include a second electrode disposed on a side of the organic light-emitting functional layer away from the substrate. The first electrode may be used as an anode or a cathode, and is not limited thereto. The material of the first electrode is not limited, and if the first electrode is formed by using an opaque conductive material and the second electrode is formed by using a transparent conductive material, the display substrate can be applied to a top emission type display panel (light of the top emission type panel is emitted from the second electrode side); in this case, the first electrode may be reused as a reflective electrode, and the material of the first electrode may include opaque metals, such as: silver or aluminum; the material of the second electrode may include transparent metal oxides such as: IGZO (Indium Gallium Zinc Oxide) or ITO (Indium Tin Oxide). If the first electrode is formed using a transparent conductive material and the second electrode is formed using an opaque conductive material, the display substrate can be applied to a bottom emission type display panel (light of the bottom emission type panel is emitted from the first electrode side).

Alternatively, referring to fig. 7, the ratio of the thickness H1 of the first defining part 211 in the direction perpendicular to the substrate 1 to the thickness H3 of the first electrode 4 in the direction perpendicular to the substrate 1 ranges from 1 to 6. By way of example, the ratio range may be 1, 1.5, 2, 3, 4, 5, 6, and so forth. To achieve still further effects, a ratio of a thickness of the first defining portion in a direction perpendicular to the substrate to a thickness of the first electrode in the direction perpendicular to the substrate ranges from 1 to 1.5.

If the thickness of the first electrode in the direction perpendicular to the substrate is greater than the thickness of the first defining portion in the direction perpendicular to the substrate, the first defining portion cannot function to define and isolate the first electrode, and therefore the thickness of the first electrode in the direction perpendicular to the substrate needs to be smaller than the thickness of the first defining portion in the direction perpendicular to the substrate. If the ratio of the thickness of the first defining part in the direction perpendicular to the substrate to the thickness of the first electrode in the direction perpendicular to the substrate is too large, the minimum ink bearing (Loading) volume between two adjacent second defining parts is increased, the improvement of ink flowability is not facilitated, and the production cost is increased. Therefore, in the display substrate provided by the application, the ratio of the thickness of the first defining part in the direction perpendicular to the substrate to the thickness of the first electrode in the direction perpendicular to the substrate is in the range of 1-6, so that the minimum ink bearing volume between two adjacent second defining parts can be reduced, and the ink fluidity is improved; meanwhile, the production cost can be reduced, and the product popularization is facilitated.

Alternatively, as shown in fig. 8 to 10, the second defining part 221 is disposed along the first direction (OB direction); an orthogonal projection of the second defining portion on the substrate overlaps an orthogonal projection of a portion of the first defining portion disposed in the first direction on the substrate.

The orthographic projection of the second defining part on the substrate is overlapped with the orthographic projection of the part, arranged along the first direction, of the first defining part on the substrate, and at the moment, the second defining parts are arranged on the sides, far away from the substrate, of the part, arranged along the first direction, of the first defining part, so that the uniformity of film formation in the plurality of openings arranged along the first direction is further ensured.

Further optionally, in order to reduce the manufacturing difficulty and ensure the fluidity of the ink, the second defining portion is in the shape of a strip. The shape of the cross section of the second defining portion in the direction perpendicular to the substrate is not limited here.

Alternatively, the shape of the cross section of the second defining portion in the direction perpendicular to the substrate may include a trapezoid, a triangle, or a semicircle. Fig. 5 and 7 are illustrated by taking a trapezoid as an example.

Alternatively, the material of the first and second defining portions includes resin or inorganic material.

For example, the material of the first defining portion may include silicon oxide or silicon nitride, and the material of the second defining portion may include a polymer resin, and specifically may be a fluorine-containing organic material, such as: polytetrafluoroethylene, polyvinylidene fluoride, heptafluoroacrylate, and the like.

The ultraviolet ray (UV) or O may be used₃(ozone) treating the first and second defined portions to change the surface energy to adjust the contact angle; alternatively, the materials of the first and second defining portions may be treated with a siloxane organic material-assembled monolayer to change the surface energy and thereby adjust the contact angle.

Alternatively, in order to implement a color picture display, the plurality of light emitting units are divided into a red light emitting unit, a green light emitting unit, and a blue light emitting unit. Referring to fig. 10, the plurality of light emitting cells arranged in the first direction (i.e., OB direction of fig. 10) are light emitting cells of the same color, and the red light emitting cell R, the green light emitting cell G, and the blue light emitting cell B are arranged in the second direction (i.e., OA direction of fig. 10), wherein the first direction is the same as the direction in which the second defining portions are arranged, and the second direction is the same as the arrangement direction of the plurality of second defining portions.

It should be noted that, the display substrate provided in the present application may further include a plurality of transistors, the transistors are disposed on a side of the pixel defining layer close to the substrate, the transistors are configured to provide a voltage to the first electrode, and a specific structure of the transistors may refer to the related art. Of course, the display substrate may further include a package layer, a touch layer, and other structures, which are not described herein again.

The embodiment of the invention also provides a display panel which comprises the display substrate.

The display panel may be an OLED (Organic Light-Emitting Diode) display panel, and any product or component with a display function, such as a television, a digital camera, a mobile phone, a tablet computer, and the like, including the display panel. The display panel can greatly reduce the poor Mura display and reduce the phenomena of color crosstalk and thin and dark lines; meanwhile, the precision requirement on the printer is reduced, and the display device has the characteristics of good display effect, long service life and the like.

Reference herein to "one embodiment," "an embodiment," or "one or more embodiments" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Moreover, it is noted that instances of the word "in one embodiment" are not necessarily all referring to the same embodiment.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the application may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.

Claims

1. A display substrate, comprising: a substrate, and a pixel defining layer disposed on the substrate;

2. The display substrate according to claim 1, wherein a ratio of a thickness of the first defining portion in a direction perpendicular to the substrate to a thickness of the second defining portion in the direction perpendicular to the substrate is in a range of 1/5-1/3.

3. The display substrate according to claim 1, wherein the light-emitting unit further comprises a first electrode disposed on a side of the organic light-emitting functional layer adjacent to the substrate;

4. The display substrate according to claim 1, wherein a ratio of a thickness of the first defining portion in a direction perpendicular to the substrate to a thickness of the first electrode in the direction perpendicular to the substrate is in a range of 1 to 6.

5. The display substrate according to claim 1, wherein the second defining portion is provided in a first direction;

6. The display substrate of claim 5, wherein the second defining portion is a stripe.

7. The display substrate according to claim 6, wherein a shape of a cross section of the second defining portion in a direction perpendicular to the substrate includes a trapezoid, a triangle, or a semicircle.

8. The display substrate according to claim 1, wherein a material of the first and second defining portions comprises a resin or an inorganic material.

9. The display substrate according to claim 1, wherein the plurality of light emitting cells are divided into red light emitting cells, green light emitting cells, and blue light emitting cells;

10. A display panel comprising the display substrate according to any one of claims 1 to 9.