Display substrate and manufacturing method thereof, and display device

Abstract

The present invention relates to a display substrate and a preparation method thereof, and a display device. The display substrate includes a base and a retaining wall formed on the base; the retaining wall separates a plurality of sub-pixel regions on the base; and the side of the retaining wall facing the sub-pixel region and the junction with the base are configured to have a first slope obtained after laser etching, and the first slope is greater than a set value. In the above-mentioned display substrate, the side of the retaining wall facing the sub-pixel region has a first slope obtained after laser etching. On the one hand, it can reduce the distance that the retaining wall extends to the sub-pixel region and increase the area of ​​the opening region, thereby improving the aperture ratio of the display substrate. On the other hand, when the retaining wall has a larger slope at the junction with the base, the droplets printed by inkjet in the sub-pixel region are less likely to climb, which helps to improve the uniformity of film formation and enhance the display quality.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a display substrate and a preparation method thereof, and a display device. Background Art

[0002] Organic Light Emitting Diode (OLED) has achieved rapid development and is widely used in display products due to its many advantages such as self-luminescence, high brightness, high contrast, fast response speed, wide viewing angle, simple structure and flexible display. Compared with the low material utilization rate faced by the conventional evaporation method for making OLED devices, inkjet printing technology (IJP) has gradually been widely used in the field of flat panel displays due to its advantages such as high material utilization rate and low cost. The printing methods of inkjet printing technology include Side by Side (SBS) and Line bank. The Line bank printing method is widely used in the production of OLED devices due to its advantages such as high printing uniformity and fast speed.

[0003] When using inkjet printing to prepare the light-emitting layer and other structures in OLED devices, it is necessary to pre-make a pixel definition layer on the substrate, which is generally manifested as a retaining wall of a certain height, which can limit the ink droplets to be accurately sprayed into the light-emitting area of ​​the specified pixel.

[0004] In the prior art, when preparing OLED devices by inkjet printing, there are some technical problems:

[0005] The slope of the junction between the retaining wall structure and the substrate is small, and there is a long transition zone at the bottom side of the retaining wall. The thickness of this transition zone is small, but it extends a long distance to the pixel area. This transition zone is opaque, which limits the area of ​​the opening area of ​​each pixel, resulting in a low aperture ratio of the display device, especially for high-resolution display devices, which will more obviously affect the upper limit of the brightness of the display device. Moreover, the existence of this transition zone will also cause obvious climbing between the droplets and the retaining wall structure in the pixel area of ​​inkjet printing, which will affect the uniformity of film formation and thus affect the display quality. Summary of the invention

[0006] The present invention provides a display substrate and a preparation method thereof, and a display device, so as to solve the technical problems in the prior art that the retaining wall structure affects the aperture ratio and causes the climbing phenomenon of inkjet printed droplets.

[0007] The display substrate provided by the present invention comprises a base and a retaining wall formed on the base; the retaining wall separates a plurality of sub-pixel areas on the base; the side of the retaining wall facing the sub-pixel area and the junction with the base are configured to have a first slope obtained after laser etching, and the first slope is greater than a set value.

[0008] Wherein, the first slope ranges from 60 to 90 degrees.

[0009] Wherein, the retaining wall comprises a hydrophilic layer, a hydrophobic layer and a covering layer; the hydrophobic layer is formed on the hydrophilic layer, and the covering layer covers the hydrophilic layer and the hydrophobic layer.

[0010] Wherein, the retaining wall further comprises a heat-conducting layer, the hydrophilic layer, the hydrophobic layer and the covering layer are sleeved on the outside of the heat-conducting layer, and the heat-conducting layer extends from the bottom end of the hydrophilic layer to the top end of the covering layer.

[0011] Wherein, the retaining wall further comprises a phase change energy storage layer, and the phase change energy storage layer is a phase change material; the phase change energy storage layer is formed above the covering layer and the heat conducting layer, and is connected to the heat conducting layer.

[0012] Wherein, the material of the phase change energy storage layer is a mixture of organic phase change material and inorganic phase change material.

[0013] Among them, the organic phase change material in the phase change energy storage layer is paraffin or acetic acid; the inorganic phase change material in the phase change energy storage layer is metal, metal alloy, crystalline hydrated salt or molten salt.

[0014] The present invention provides a method for preparing a display substrate, which comprises:

[0015] forming a retaining wall structure on the base;

[0016] Laser etching is performed on the junction of the formed retaining wall structure and the substrate, so that the slope between the retaining wall structure and the substrate is a first slope greater than a set value.

[0017] The step of forming a retaining wall structure on the substrate includes:

[0018] forming a hydrophilic material layer on a substrate;

[0019] forming a hydrophobic material layer on top of the hydrophilic material;

[0020] Exposing, developing and etching the hydrophilic material layer and the hydrophobic material layer formed on the substrate to form patterns of the hydrophilic layer and the hydrophobic layer;

[0021] A material forming a cover layer over the hydrophilic material layer and the hydrophobic material layer;

[0022] The material of the cover layer is exposed, developed and etched to form a pattern of the cover layer.

[0023] Wherein, the step of forming a retaining wall structure on the substrate further comprises:

[0024] forming a thermally conductive material layer on the substrate;

[0025] exposing, developing and etching the thermal conductive material layer formed on the substrate to form a pattern of the thermal conductive layer;

[0026] The steps of forming a thermally conductive material layer and forming a pattern of the thermally conductive layer are performed before the step of forming the hydrophilic material layer.

[0027] Wherein, the method for preparing the display substrate comprises:

[0028] forming a phase change energy storage material layer above the cover layer and the heat conductive layer;

[0029] The formed phase-change energy storage material layer is exposed, developed and etched to form a pattern of the phase-change energy storage layer, and the formed phase-change energy storage layer is connected to the upper end of the heat-conducting layer.

[0030] The display device provided by the present invention includes the above-mentioned display substrate.

[0031] The display substrate and its preparation method, and the display device provided by the present invention have the following advantages compared with the prior art:

[0032] The display substrate provided by the present invention has a first slope obtained by laser etching on the side of the retaining wall facing the sub-pixel area. Since the laser has a high collimation, the retaining wall is formed by laser etching, and the longer extension area of ​​the retaining wall at the junction with the substrate toward the sub-pixel area can be removed, so that the junction of the retaining wall and the substrate has a larger slope. This arrangement, on the one hand, can reduce the distance that the retaining wall extends toward the sub-pixel area, increase the area of ​​the opening area, and thus improve the aperture ratio of the display substrate. On the other hand, when the junction of the retaining wall and the substrate has a larger slope, the droplets of inkjet printing in the sub-pixel area are not prone to climbing, which helps to improve the uniformity of film formation and enhance the display quality.

[0033] The method for preparing a display substrate provided by the present invention adopts a laser etching process to prepare the above-mentioned display substrate, and has the same beneficial effects as the above-mentioned display substrate, which will not be described in detail.

[0034] The display device provided by the present invention includes the above-mentioned display substrate and has the same beneficial effects as the above-mentioned display substrate, which will not be described in detail. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0037] Figure 1 is a schematic structural diagram of a display substrate in an embodiment of the present invention;

[0038] Figure 2 It is a schematic diagram of the process of the method for preparing a display substrate in an embodiment of the present invention.

[0039] In the figure:

[0040] 10-base; 20-retaining wall;

[0041] 201 - hydrophilic layer; 202 - hydrophobic layer; 203 - covering layer; 204 - thermal conductive layer; 205 - phase change energy storage layer; 206 - insulating filling layer. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] Embodiments of a display substrate and a method for manufacturing the same, and a display device provided by the present invention are described below with reference to the accompanying drawings.

[0044] In one embodiment of the display substrate of the present invention, referring to Figure 1 The display substrate includes a base 10 and a retaining wall 20 formed on the base 10. The retaining wall 20 separates a plurality of sub-pixel regions on the base 10. The side of the retaining wall 20 facing the sub-pixel region and the junction with the base 10 are configured to have a first slope obtained after laser etching, and the first slope is greater than a set value.

[0045] As described in the background technology section, in existing display products, the slope of the retaining wall is relatively small, and the junction with the substrate has a transition zone that extends longer toward the sub-pixel area. This transition zone, on the one hand, results in a smaller area of ​​the opening area, and on the other hand, it also causes an obvious climbing phenomenon. The reason for the above problem is that when preparing the retaining wall, the material of the retaining wall is usually first deposited or coated on the substrate, and then the structure of the retaining wall is formed through processes such as exposure, development, and etching. The retaining wall structure prepared by this method will have a smaller slope at the junction with the substrate and will have the above-mentioned transition zone.

[0046] In the embodiment of the present invention, the retaining wall 20 is configured as a structure processed by laser etching. The laser has a high collimation. By using laser etching to form the retaining wall 20, the longer extension area of ​​the retaining wall 20 at the junction with the substrate 10 toward the sub-pixel area can be removed, so that the junction of the retaining wall 20 with the substrate 10 has a larger slope, which can reach above the lower limit of the first slope. This arrangement, on the one hand, reduces the distance that the retaining wall 20 extends toward the sub-pixel area, and can increase the area of ​​the opening area, thereby improving the aperture ratio of the display substrate. On the other hand, when the junction of the retaining wall 20 with the substrate 10 has a larger slope, the droplets of inkjet printing in the sub-pixel area are not prone to climbing, which helps to improve the uniformity of film formation and enhance the display quality.

[0047] In one embodiment of the present invention, the first slope ranges from 60 to 90 degrees. When the slope between the retaining wall 20 and the substrate 10 is within this range, the length of the retaining wall 20 extending toward the sub-pixel region is not too large, thereby ensuring the aperture ratio; and within this slope range, the climbing phenomenon of the inkjet-printed liquid in the sub-pixel region can be effectively improved.

[0048] In the embodiment of the present invention, the first slope of the retaining wall 20 connected to the base 10 may be the actual slope angle of the side of the lower end (the end connected to the base 10) of the retaining wall 20. Alternatively, the side edges of the upper and lower ends of the retaining wall 20 ( Figure 1 The angle between the line connecting point A and point B in the figure and the base 10.

[0049] In one embodiment of the present invention, the retaining wall 20 includes a hydrophilic layer 201, a hydrophobic layer 202 and a covering layer 203. The hydrophobic layer 202 is formed on the top of the hydrophilic layer 201, and the covering layer 203 covers the top of the hydrophilic layer 201 and the hydrophobic layer 202. Specifically, the material of the hydrophilic layer 201 can be ITO (indium tin oxide), Ag (silver), etc. The hydrophilic layer 201 formed by these hydrophilic materials has good affinity with the substrate 10, which is conducive to the spreading of droplets of inkjet printing in the sub-pixel area. Generally, the thickness of the hydrophilic layer 201 can be 10 to 30 nanometers. When the device to be formed in the sub-pixel area is an OLED device, the thickness of the hydrophilic layer 201 can be set to have a thickness substantially consistent with that of the hole injection layer in the OLED device. The material of the hydrophobic layer 202 can be an inorganic substance containing F (fluorine). The thickness of the hydrophobic layer 202 can be 10 to 50 nanometers. When the device to be formed in the sub-pixel region is an OLED device, the thickness of the hydrophobic layer 202 can be set to be substantially the same as the thickness of the hole transport layer in the OLED device. The hydrophobic layer 202 is conducive to reducing the climbing phenomenon of the droplets of inkjet printing in the sub-pixel region on the side of the retaining wall 20. The material of the covering layer 203 can be an organic glue material, and its thickness can be 0.5 to 2 microns.

[0050] In one embodiment of the present invention, the retaining wall 20 may include not only the above-mentioned hydrophilic layer 201, the hydrophobic layer 202 and the covering layer 203, but also a heat-conducting layer 204. The hydrophilic layer 201, the hydrophobic layer 202 and the covering layer 203 are encircled on the outside of the heat-conducting layer 204, and the heat-conducting layer 204 extends from the bottom end of the hydrophilic layer 201 to the top end of the covering layer 203. The heat-conducting layer 204 can conduct the heat emitted by, for example, OLED devices to the outside during the operation of the display substrate. The material of the heat-conducting layer 204 can be Au (gold), Ag (silver), Cu (copper), Al (aluminum), Mg (magnesium) and other metals with good thermal conductivity, and the thickness of the heat-conducting layer 204 can be 1 to 2 microns.

[0051] In one embodiment of the present invention, the retaining wall 20 may further include an insulating filling layer 206, which may be formed on the outside of the heat-conducting layer 204 and wrap the heat-conducting layer 204. The material of the insulating filling layer may specifically be metal oxides, such as Al2O3, MGO, ZnO, NiO, etc., metal nitrides, such as AlN, Si3N4, BN, and SiC ceramics. These materials allow the insulating filling layer 206 to have both high thermal conductivity and good insulation performance. The insulating filling layer 206 is arranged to surround the heat-conducting layer 204, which, on the one hand, assists the heat-conducting layer 204 in heat conduction and improves the efficiency of heat conduction, and on the other hand, can also reduce the overall electrical conductivity of the retaining wall 20. The height of the insulating filling layer 206 (the size in the longitudinal direction shown in the figure) may be between 1 and 2 microns, which is consistent with the heat-conducting layer 204; the width of the heat-conducting layer 206 (the size in the transverse direction shown in the figure) may be 0.5 to 1 micron.

[0052] In one embodiment of the present invention, the retaining wall 20 includes not only a hydrophilic layer 201, a hydrophobic layer 202, a covering layer 203 and a heat-conducting layer 204, but also a phase-change energy storage layer 205, which is formed above the covering layer 203 and the heat-conducting layer 204 and is in contact with the heat-conducting layer 204. The phase-change energy storage layer 205 can absorb the heat conducted by the heat-conducting layer 204, thereby reducing the temperature of related devices and regions on the display substrate, avoiding excessive temperature, and helping to avoid display abnormalities or device damage due to excessive temperature in a local area.

[0053] In one embodiment of the present invention, the phase change energy storage layer 205 is a phase change material. The phase change material has good heat exchange performance, and can effectively and quickly absorb heat from the outside for storage. In this embodiment, the heat conducted from the relevant area of ​​the display substrate can be effectively absorbed to reduce the temperature of the relevant area.

[0054] Specifically, the phase change energy storage layer 205 is a composite phase change material obtained by mixing an inorganic phase change material and an organic phase change material, wherein the inorganic phase change material may be metal, metal alloy, crystalline hydrated salt, molten salt, etc., and the organic phase change material may be paraffin, acetic acid, etc.

[0055] When implementing the display substrate of the present invention, the retaining wall 20 is not limited to the structure in the above-mentioned embodiments, and can also be other various structures. For example, one or more of the hydrophilic layer 201, the hydrophobic layer 202, the covering layer 203, the heat-conducting layer 204 and the phase-change energy storage layer 205 can be omitted, or the retaining wall 20 is a completely different structure, as long as the retaining wall 20 has a certain height, can define the sub-pixel area on the substrate, and its side facing the sub-pixel area is processed by laser etching to have a first slope.

[0056] In the display substrate provided by the above embodiment of the present invention, the side of the retaining wall 20 facing the sub-pixel region has a first slope obtained by laser etching. Since the laser has a high collimation, the retaining wall 20 is formed by laser etching, and the longer extension area of ​​the retaining wall 20 at the junction with the substrate 10 toward the sub-pixel region can be removed, so that the junction of the retaining wall 20 with the substrate 10 has a larger slope. In this way, on the one hand, the distance that the retaining wall 20 extends to the sub-pixel region can be reduced, and the area of ​​the opening area can be increased, thereby improving the aperture ratio of the display substrate. On the other hand, when the junction of the retaining wall 20 with the substrate 10 has a larger slope, the droplets of inkjet printing in the sub-pixel region are not prone to climbing, which helps to improve the uniformity of film formation and enhance the display quality.

[0057] In one embodiment of the method for preparing a display substrate of the present invention, the method for preparing a display substrate comprises the following steps S1 to S2: Figure 2 shown.

[0058] Step S1, forming a retaining wall structure on a substrate.

[0059] In step S1, the formed retaining wall structure defines a plurality of sub-pixel regions on the substrate, and each sub-pixel region is used to form at least a partial structure of a light-emitting device such as an OLED by inkjet printing or the like.

[0060] The retaining wall structure to be formed can have different structural forms. Figure 1 Taking the retaining wall 20 shown in the figure as an example, the retaining wall structure to be formed may have structures such as a hydrophilic layer 201, a hydrophobic layer 202, a covering layer 203, a thermal conductive layer 204 and a phase change energy storage layer 205. When forming it on a substrate, the following steps S11 to S17 are included, such as Figure 2 shown.

[0061] Step S11, providing a substrate 10, and forming structures such as TFT on the substrate.

[0062] In step S11 , the substrate 10 may be made of glass or other materials, such as polyimide.

[0063] Step S12, forming a pattern of the heat conducting layer 204.

[0064] When forming the pattern of the heat-conducting layer in step S12, firstly, a heat-conducting material layer is formed on the substrate by deposition or sputtering, and the material of the heat-conducting material layer can be one or more of Au (gold), Ag (silver), Cu (copper), Al (aluminum), Mg (magnesium), etc. Then, photoresist is coated, and the pattern of the heat-conducting layer 204 is obtained through steps such as exposure, development, and etching.

[0065] Step S13 , forming a pattern of the insulating filling layer 206 surrounding the heat conducting layer 204 .

[0066] When forming the pattern of the insulating filling layer 206 in step S13, firstly, an insulating material layer is formed by deposition or sputtering, and the material of the insulating material layer can be metal oxides, such as Al2O3, MGO, ZnO, NiO, etc., metal nitrides, such as AlN, Si3N4, BN, and SiC ceramics. These materials can make the insulating filling layer 206 have both high thermal conductivity and good insulation performance. Then, photoresist is applied, and the pattern of the insulating filling layer 206 is obtained through steps such as exposure, development and etching.

[0067] The insulating filling layer 206 surrounds the heat-conducting layer 204, which, on the one hand, assists the heat-conducting layer 204 in heat conduction and improves the efficiency of heat conduction, and on the other hand, can also reduce the overall conductivity of the retaining wall 20. The height of the insulating filling layer 206 (the dimension in the longitudinal direction as shown in the figure) can be between 1 and 2 microns, which is consistent with the heat-conducting layer 204; the width of the heat-conducting layer 206 (the dimension in the transverse direction as shown in the figure) can be 0.5 to 1 micron.

[0068] Step S14, forming a pattern of the hydrophilic layer 201.

[0069] In step S14, when forming the pattern of the hydrophilic layer 201, firstly, a layer of hydrophilic material is formed by deposition, etc. Then, photoresist is coated, and the pattern of the hydrophilic layer 201 is obtained through steps of exposure, development and etching.

[0070] Specifically, the selected hydrophilic material may be ITO, Ag, etc. These hydrophilic materials have good affinity with the substrate 10 and are helpful for the spreading of droplets in the sub-pixel region during inkjet printing.

[0071] The thickness of the formed hydrophilic layer 201 may be 10 to 30 nanometers. When the display device formed in the sub-pixel region is an OLED, the thickness of the hydrophilic layer 201 may be configured to be substantially consistent with the thickness of the hole injection layer.

[0072] Step S15, forming a pattern of the hydrophobic layer 202.

[0073] In step S15, when forming the pattern of the hydrophobic layer 202, firstly, a layer of hydrophobic material is formed by deposition or the like. Then, photoresist is coated, and the pattern of the hydrophobic layer 202 is obtained through steps of exposure, development, and etching.

[0074] Specifically, the selected hydrophobic material may be an inorganic substance containing F (fluorine). The thickness of the formed hydrophobic layer 202 may be 10 to 50 nanometers. When the display device formed in the sub-pixel region is an OLED, the thickness of the hydrophobic layer 202 may be configured to be substantially consistent with the thickness of the hole transport layer.

[0075] Step S16, forming a pattern of the covering layer 203.

[0076] In step S16, when forming the pattern of the cover layer 203, firstly, a layer of material is formed by deposition or the like. Then, photoresist is coated, and the pattern of the cover layer 203 is obtained through steps of exposure, development, and etching.

[0077] Specifically, the selected material may be an organic adhesive, etc. The thickness of the formed covering layer 203 may be 0.5-2 microns.

[0078] Specifically, the exposure, development and etching in steps S14, S15 and S16 can be implemented in a single process. At this time, after the hydrophilic material layer is formed, the exposure and etching processes are not performed, and the hydrophobic material layer is continuously formed. At this time, the exposure and etching processes are still not performed, and then the material of the cover layer 203 is formed. Finally, the exposure, development and etching processes are performed once. In this single process, the patterns of the hydrophilic layer 201, the hydrophobic layer 202 and the cover layer 203 are formed simultaneously.

[0079] Step S2, laser etching is performed on the junction of the formed retaining wall structure with the substrate, so that the slope between the retaining wall structure and the substrate is a first slope greater than a set value.

[0080] In step S2, taking the retaining wall structure formed by the above S11 to S16 (a part of the retaining wall structure, the complete structure of the retaining wall has not yet been formed, and other unformed structures are performed after step S2) as an example, the parts of the hydrophilic layer 201, the hydrophobic layer 202 and the covering layer 203 extending to the sub-pixel area are laser etched.

[0081] In this step, the portion of the hydrophilic layer 201, the hydrophobic layer 202 and the covering layer 203 extending toward the sub-pixel region is irradiated with laser, and the portion can be removed. Since the laser has high collimation, the edge of the hydrophilic layer 201, the hydrophobic layer 202 and the covering layer 203 formed by laser etching and connected to the substrate 10 can have a large slope, and the slope can be above the lower limit of the first slope.

[0082] The portion of the retaining wall 20 formed by the above treatment extending toward the sub-pixel region becomes smaller, and the portion connecting with the substrate 10 has a greater slope. This can increase the area of ​​the sub-pixel region, that is, increase the area of ​​the opening region, thereby increasing the aperture ratio of the display substrate. On the other hand, when the portion connecting the retaining wall 20 with the substrate 10 has a greater slope, the droplets printed by inkjet in the sub-pixel region are less likely to climb, thereby helping to improve the uniformity of film formation and enhance display quality.

[0083] In this step, after laser etching, the first slope of the retaining wall structure and the slopes of the hydrophilic layer 201 , the hydrophobic layer 202 , the covering layer 203 and the substrate 10 can be in the range of 60 to 90 degrees.

[0084] Specifically, the first slope of the retaining wall 20 connected to the base 10 may be the actual slope angle of the side of the lower end (the end connected to the base 10) of the retaining wall 20. Alternatively, the side edges of the upper and lower ends of the retaining wall 20 ( Figure 1 The angle between the line connecting point A and point B in the figure and the base 10.

[0085] Step S17, forming a pattern of the phase change energy storage layer 205.

[0086] In step S17, when forming the pattern of the phase change energy storage layer 205, first, a phase change energy storage material layer is formed above the covering layer and the thermal conductive layer by deposition or the like; then, a photoresist is coated, and the formed phase change energy storage material layer is exposed, developed and etched to form the pattern of the phase change energy storage layer, and the formed phase change energy storage layer is connected to the upper end of the thermal conductive layer.

[0087] Specifically, the selected phase change material can be a composite phase change material, which can be a mixture of an organic phase change material and an inorganic phase change material, wherein the inorganic phase change material can be selected from metals, metal alloys, crystalline hydrated salts, molten salts, etc., and the organic phase change material can be paraffin, acetic acid, etc.

[0088] The thickness of the phase change energy storage layer 205 formed in step S17 may be 0.05 to 1 micrometer. The energy storage density of the phase change material layer 205 may be above 100 J / g to obtain a good energy storage effect.

[0089] The phase change energy storage layer 205 formed in step S17 can absorb the heat conducted by the thermal conductive layer 204, thereby reducing the temperature of related devices and regions on the display substrate to prevent the temperature from being too high, which helps to avoid display anomalies or device damage caused by excessive temperature in local areas.

[0090] Moreover, for the phase-change energy storage layer 205, its phase-change temperature can be set close to the critical temperature by configuring the type selection and ratio of the selected organic phase-change material and the inorganic phase-change material. The critical temperature can be the temperature at which the relevant area on the display substrate (such as the light-emitting device such as the OLED formed in the sub-pixel area) has poor display or the device is damaged or decomposed due to high temperature. By setting the temperature of the phase-change energy storage layer 205 lower than but close to the adjacent temperature, the phase change can occur before the relevant area of ​​the display substrate is abnormal, and it can change into a fluid, cover the relevant area, form a device short circuit in the area, and the local relevant area becomes a dark spot, thereby avoiding the abnormal bright spot on the display substrate due to high temperature (for the display substrate, the bright spot will affect the display effect more than the dark spot, and the dark spot is easier to handle) or causing the entire display substrate to be damaged due to high temperature.

[0091] In one embodiment of the display device of the present invention, the display device includes the above-mentioned display substrate.

[0092] In one embodiment, the display device may specifically be an OLED display device or a QLED display device.

[0093] The display device in the embodiment of the present invention includes the above-mentioned display substrate, and thus has the same beneficial effects as the above-mentioned display substrate, which will not be described in detail.

[0094] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0095] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A display substrate, characterized in that: The display substrate comprises a base and a retaining wall formed on the base; the retaining wall separates a plurality of sub-pixel regions on the base; The junction of the side of the retaining wall facing the sub-pixel area and the substrate is configured to have a first slope obtained after laser etching, the first slope is greater than a set value, the first slope is the actual slope angle of the side of the end of the retaining wall connected to the substrate or the angle between the connecting line between the side edges of the upper end and the lower end of the retaining wall and the substrate, and the set value is 60 degrees; The retaining wall comprises a hydrophilic layer, a hydrophobic layer and a covering layer; The hydrophobic layer is formed on the hydrophilic layer, and the covering layer covers the hydrophilic layer and the hydrophobic layer; The retaining wall further comprises a heat-conducting layer, the hydrophilic layer, the hydrophobic layer and the covering layer are sleeved on the outside of the heat-conducting layer, and the heat-conducting layer extends from the bottom end of the hydrophilic layer to the top end of the covering layer; The retaining wall further comprises a phase change energy storage layer, which is a phase change material; the phase change energy storage layer is formed above the covering layer and the heat conducting layer, and is connected to the heat conducting layer.

2. The display substrate according to claim 1, characterized in that: The first slope ranges from 60 to 90 degrees.

3. The display substrate according to claim 1, characterized in that: The material of the phase change energy storage layer is a mixture of organic phase change material and inorganic phase change material.

4. The display substrate according to claim 3, characterized in that: The organic phase change material in the phase change energy storage layer is paraffin or acetic acid; The inorganic phase change material in the phase change energy storage layer is a metal, a metal alloy, a crystalline hydrated salt or a molten salt.

5. A method for preparing a display substrate, characterized in that: For preparing a display substrate according to any one of claims 1 to 4, the method for preparing the display substrate comprising: forming a retaining wall structure on the base; Laser etching is performed on the junction of the formed retaining wall structure and the substrate, so that the slope between the retaining wall structure and the substrate is a first slope greater than a set value.

6. The method for preparing a display substrate according to claim 5, characterized in that: The steps of forming a retaining wall structure on a substrate include: forming a hydrophilic material layer on a substrate; forming a hydrophobic material layer on top of the hydrophilic material; Exposing, developing and etching the hydrophilic material layer and the hydrophobic material layer formed on the substrate to form patterns of the hydrophilic layer and the hydrophobic layer; A material forming a cover layer over the hydrophilic material layer and the hydrophobic material layer; The material of the cover layer is exposed, developed and etched to form a pattern of the cover layer.

7. The method for preparing a display substrate according to claim 6, characterized in that: The step of forming a retaining wall structure on the substrate also includes: forming a thermally conductive material layer on a substrate; exposing, developing and etching the thermal conductive material layer formed on the substrate to form a pattern of the thermal conductive layer; The steps of forming a thermally conductive material layer and forming a pattern of the thermally conductive layer are performed before the step of forming the hydrophilic material layer.

8. The method for preparing a display substrate according to claim 7, characterized in that: The method for preparing the display substrate comprises: forming a phase change energy storage material layer above the cover layer and the heat conductive layer; The formed phase-change energy storage material layer is exposed, developed and etched to form a pattern of the phase-change energy storage layer, and the formed phase-change energy storage layer is connected to the upper end of the heat-conducting layer.

9. A display device, characterized in that: The display device comprises the display substrate according to any one of claims 1 to 4.

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