Display panel and preparation method thereof

Abstract

The invention provides a display panel and a preparation method thereof, the display panel comprises a substrate, a driving circuit layer, a light-emitting function layer and a packaging layer, the driving circuit layer, the light-emitting function layer and the packaging layer are sequentially stacked on the substrate, the packaging layer comprises an organic packaging layer, and the organic packaging layer is doped with a photocatalytic material. Compared with the prior art, the organic material is doped with the photocatalytic material, so that on one hand, the photocatalytic material has a rich pore structure and can prolong a water-oxygen molecule transmission path and improve the water-oxygen barrier property of the organic packaging layer; on the other hand, in the curing process, the photocatalytic material can decompose water molecules in the organic packaging layer, the water content in the organic packaging layer is reduced, the packaging effect of the organic packaging layer is further improved, and the service life of the device is prolonged.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and more specifically, to a display panel and a method for manufacturing the same. Background Art

[0002] OLED (Organic Light-Emitting Diode) devices have gradually become the mainstream choice for high-end products in the display industry due to their advantages such as wide color gamut, wide viewing angle, high contrast, fast response speed, low power consumption, and suitability for flexible substrates. They have a broad market in mobile phones, wearables, computers, and automotive products.

[0003] The light-emitting layer of OLED devices is mostly made of organic materials. The device life and performance stability are easily affected by water and oxygen, so it needs to be encapsulated to prevent water and oxygen erosion. The current traditional encapsulation structure is limited by the length of the pores in the organic encapsulation layer, and its water and oxygen barrier capacity is limited, and its encapsulation effect needs to be further improved. Summary of the invention

[0004] The purpose of the present disclosure is to provide a display panel and a method for manufacturing the same, so as to improve the encapsulation effect of the encapsulation layer of the display panel in the related art and enhance the life and performance of the display panel.

[0005] In order to achieve the above objectives, the present invention adopts the following technical solutions:

[0006] A first aspect of the present disclosure provides a display panel, comprising a substrate, a driving circuit layer, a light-emitting functional layer and an encapsulation layer sequentially stacked on the substrate, wherein the encapsulation layer comprises an organic encapsulation layer doped with a photocatalytic material.

[0007] Optionally, the photocatalytic material is in powder form, has a porous structure and a specific surface area greater than 100 m 2 / g.

[0008] Optionally, the light transmittance of the photocatalytic material is greater than or equal to 90%.

[0009] Optionally, the photocatalytic material satisfies: T=K*S*a*m+B, wherein T represents the encapsulation failure time, S represents the specific surface area of ​​the photocatalytic material, m represents the mass of the photocatalytic material per milliliter of organic material, a represents the saturated adsorption amount of the photocatalytic material, and K and B are constants.

[0010] Optionally, the doping ratio of the photocatalytic material in the organic material is 2-10 mg / mL, and the specific surface area of ​​the photocatalytic material is greater than or equal to 200 m 2 / g and less than or equal to 400m 2 / g.

[0011] Optionally, the photocatalytic material includes at least one of titanium oxide, zinc oxide, indium oxide, bismuth oxide, and tin oxide.

[0012] Optionally, the encapsulation layer further includes: a first inorganic encapsulation layer disposed on a side of the organic encapsulation layer close to the light-emitting functional layer and a second inorganic encapsulation layer disposed on a side away from the light-emitting functional layer.

[0013] Optionally, the organic encapsulation layer is prepared by an inkjet printing process and a light curing process.

[0014] A second aspect of the present disclosure provides a method for preparing a display panel, comprising the following steps:

[0015] providing a substrate;

[0016] A driving circuit layer, a light-emitting functional layer and a packaging layer are sequentially formed on the substrate, wherein the packaging layer comprises an organic packaging layer, and the organic packaging layer is doped with a photocatalytic material.

[0017] Optionally, the step of forming the organic encapsulation layer includes:

[0018] Inkjet printing an organic material doped with a photocatalytic material on the light-emitting functional layer to form an organic thin film layer;

[0019] The organic thin film layer is photocured to form an organic encapsulation layer.

[0020] The beneficial effects of the present disclosure are as follows:

[0021] The display panel of the disclosed embodiment, by doping photocatalytic materials into organic materials, on the one hand, the photocatalytic materials have a rich pore structure, which can extend the transmission path of water and oxygen molecules and improve the water and oxygen barrier performance of the organic encapsulation layer; on the other hand, during the process of curing to form the organic encapsulation layer, the photocatalytic materials can decompose the water molecules in the organic encapsulation layer, reduce the water content in the organic encapsulation layer, further improve the encapsulation effect of the organic encapsulation layer, and extend the life of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The specific implementation methods of the present disclosure are further described in detail below with reference to the accompanying drawings.

[0023] Figure 1 A schematic diagram of the structure of a display panel provided in an embodiment of the present disclosure;

[0024] Figure 2 A flow chart of a method for preparing a display panel provided in an embodiment of the present disclosure;

[0025] Figure 3 A schematic diagram of the process flow of a method for preparing a display panel provided in an embodiment of the present disclosure.

[0026] Figure 4 Schematic diagram of the photocatalytic material provided in an embodiment of the present disclosure decomposing water molecules under ultraviolet light. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0028] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one", "one" or "the" do not indicate quantity restrictions, but indicate that there is at least one. Similar words such as "include" or "comprise" mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Similar words such as "connect" or "connected" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0029] The light-emitting layer of OLED devices is mostly made of organic materials. The device life and performance stability are easily affected by water and oxygen. Water and oxygen invade the light-emitting layer through the packaging path and cause gradually expanding black spots (Growing Dark Spot, abbreviated as GDS). GDS black spots will seriously affect the life of the device, and as the use time increases, the adverse effects will gradually increase. Therefore, the light-emitting layer needs to be effectively packaged.

[0030] At present, traditional flexible packaging mainly adopts the packaging structure of inorganic layer + organic layer + inorganic layer. On the one hand, it can improve the bending ability of the light-emitting device. On the other hand, the organic layer can extend the path for water and oxygen to enter the light-emitting layer, thereby improving the packaging effect. In this packaging structure, the pore length of the organic layer directly affects the barrier effect of the packaging structure on water and oxygen. The pore length refers to the extension distance of the tiny channels or pores formed inside or on the surface of the organic layer. These pores are one of the main paths for external environmental factors such as water and oxygen to invade the light-emitting layer. When the pore length is short, water and oxygen can easily and quickly invade the light-emitting layer, and the water and oxygen barrier performance is poor, resulting in a decrease in device performance and a shortened life; when the pore length is long, water and oxygen need a longer path to reach the light-emitting layer, thereby increasing the possibility of water and oxygen being intercepted or absorbed, and the barrier performance is higher.

[0031] However, on the one hand, the pore length of the organic layer is limited, so the encapsulation effect is also limited; on the other hand, the organic layer needs to be solidified during the preparation process. During the evaporation of the solvent, the water and oxygen remaining in the organic solvent are difficult to completely remove by high temperature alone. The pores formed after solidification will also absorb water and oxygen during the film transfer process. The water and oxygen are encapsulated into the display panel, which will reduce the encapsulation effect and further affect the life and performance stability of the OLED device.

[0032] In order to solve the above technical problems, the embodiments of the present disclosure provide a display panel and a method for manufacturing the same, which will be described in detail below in conjunction with various specific embodiments.

[0033] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a display panel provided in an embodiment of the present disclosure is shown in FIG. Figure 1 As shown, the display panel includes a substrate 10, a driving circuit layer 20, a light-emitting functional layer 30 and an encapsulation layer 40 which are sequentially stacked on the substrate 10, and the encapsulation layer 40 includes an organic encapsulation layer 402, and the organic encapsulation layer 402 is doped with a photocatalytic material.

[0034] Optionally, the organic encapsulation layer 402 is prepared by an inkjet printing process and a light curing process. Specifically, the preparation process of the organic encapsulation layer 402 includes: (1) inkjet printing an organic material doped with a photocatalytic material to form an organic thin film layer; (2) light curing the organic thin film layer to form an organic encapsulation layer.

[0035] Optionally, the photocatalytic material has a porous structure and a large specific surface area. Exemplarily, the specific surface area is greater than 100 m 2 / g.

[0036] In the embodiment of the present disclosure, the encapsulation effect of the organic encapsulation layer is improved by doping the organic material with a photocatalytic material, which specifically includes the following aspects:

[0037] (1) Photocatalytic materials have a variety of microscopic morphologies, such as nanosheets, nanospheres, nanotubes, nanowires / rods, flower shapes, seaweed shapes, polyhedrons, and other complex three-dimensional structures, porous structures, hollow sphere structures, cluster structures, and network structures. Among them, when the microscopic shape is a cluster or network structure, the photocatalytic material has a large specific surface area and a multi-porous structure. The specific surface area refers to the surface area of ​​the catalyst per unit mass, usually expressed in square meters per gram (m2). 2 / g) as the unit.

[0038] On the one hand, the multi-porous structure can provide a more tortuous transmission path for water molecules and oxygen molecules. Compared with the straight path that directly penetrates dense materials, the pores in the multi-porous structure are intricate, which requires water and oxygen molecules to constantly change direction during the transmission process, and even get stuck in some narrow pores. This tortuous path greatly increases the resistance and time of water and oxygen molecule transmission, thereby effectively extending their transmission path.

[0039] On the other hand, the surface of photocatalytic materials with multi-porous structures usually has abundant adsorption sites, which can form stable chemical bonds or physical adsorption with water molecules and oxygen molecules. When water and oxygen molecules come into contact with the surface of the material, they will be quickly adsorbed and fixed on the adsorption sites, and it is difficult to desorb and continue to transport to the inside. This adsorption and fixation further prolongs the residence time of water and oxygen molecules on the surface of the material, reducing their chances of penetrating into the light-emitting functional layer.

[0040] In addition, a larger specific surface area allows the surface of the photocatalytic material to have more opportunities to come into contact with water molecules and oxygen molecules. Due to the increase in contact area, the adsorption and residence time of water molecules and oxygen molecules on the material surface will be prolonged accordingly, thereby slowing down their diffusion rate to the luminescent functional layer.

[0041] (2) When the organic thin film layer is cured by light, the photocatalytic material can react chemically with water molecules under light conditions, decomposing the water molecules in the organic thin film layer into hydrogen and oxygen, thereby reducing the water content in the organic layer, alleviating the erosion of the light-emitting functional layer caused by the penetration of water molecules into the light-emitting functional layer, and improving the life of the display device.

[0042] It can be seen that photocatalytic materials work together through multiple mechanisms such as providing a tortuous transmission path, enhancing adsorption and fixation, providing a larger contact area, and initiating chemical reactions to improve the water and oxygen barrier properties of the organic encapsulation layer, thereby improving the encapsulation effect of the organic encapsulation layer and extending the life of the device.

[0043] Compared with the related art, the display panel of the embodiment of the present disclosure, by doping photocatalytic materials into organic materials, on the one hand, the photocatalytic materials have a rich pore structure, which can extend the transmission path of water and oxygen molecules and improve the water and oxygen barrier performance of the organic encapsulation layer; on the other hand, during the process of curing to form the organic encapsulation layer, the photocatalytic materials can decompose the water molecules in the organic encapsulation layer, reduce the water content in the organic encapsulation layer, further improve the encapsulation effect of the organic encapsulation layer, and extend the life of the device.

[0044] In one possible implementation, Figure 1 As shown, the encapsulation layer 40 further includes: a first inorganic encapsulation layer 401 disposed on a side of the organic encapsulation layer 402 close to the light-emitting functional layer 30 and a second inorganic encapsulation layer 403 disposed on a side away from the light-emitting functional layer 30. Exemplarily, the first inorganic encapsulation layer 401 and the second inorganic encapsulation layer 403 can be formed of inorganic materials such as silicon nitride, silicon oxide, silicon oxynitride, etc., and are prepared by a chemical vapor deposition (CVD) process.

[0045] In one possible implementation, the photocatalytic material may be a metal oxide photocatalytic material, a semiconductor photocatalytic material, a composite photocatalytic material, and the like. Among them, the metal oxide photocatalytic material includes titanium oxide (TiO2), zinc oxide (ZnO), indium oxide (In2O3), bismuth oxide (Bi2O3), tin oxide (SnO2), and the like. Among them, TiO2 can absorb ultraviolet light and generate electron-hole pairs under light, thereby catalyzing redox reactions. Semiconductor photocatalytic materials refer to materials with semiconductor properties, such as titanium dioxide, zinc oxide, and the like, which can use light energy to excite electrons, thereby participating in chemical reactions, and have the advantages of high activity and good stability. Composite photocatalytic materials are materials that combine different types of photocatalytic materials to form composite materials with synergistic effects. For example, a composite photocatalytic material of titanium dioxide and zinc oxide can improve the efficiency and selectivity of photocatalytic reactions.

[0046] Optionally, the photocatalytic material in the embodiment of the present disclosure includes at least one of titanium oxide, zinc oxide, indium oxide, bismuth oxide, and tin oxide. It is understandable that the specific type of the photocatalytic material can be selected according to actual needs and is not limited to the several types listed as examples in the embodiment of the present disclosure.

[0047] Furthermore, in order to regulate the optical properties of the organic encapsulation layer, the photocatalytic material is a composite photocatalytic material. Exemplarily, the photocatalytic material is a composite photocatalytic material of titanium dioxide and zinc oxide. Since composite photocatalytic materials are usually composed of two or more materials of different properties, each of which has its own characteristics in optical properties, by selecting materials with different optical properties for compounding, it is possible to achieve regulation of the overall optical properties of the composite photocatalytic material, and then achieve regulation of the optical properties of the organic encapsulation layer. For example, a semiconductor material with excellent light absorption performance can be selected for compounding with a metal oxide with high catalytic activity, thereby combining the advantages of both and improving the photocatalytic efficiency and optical properties of the composite material. In addition, there is often a synergistic effect between the different components in the composite photocatalytic material, and this synergistic effect can make the composite material exhibit better performance in optical properties than a single component.

[0048] In a possible implementation, the photocatalytic material is in powder form, and the organic material is in liquid form. When the photocatalytic material is doped into the organic material, the following steps may be included:

[0049] (1) Purify the photocatalytic material powder to remove impurities and surface adsorbents and improve its catalytic activity, usually including steps such as washing and drying.

[0050] (2) Slowly add the purified photocatalytic material powder to the liquid organic material. During this process, a stirrer can be used for sufficient stirring to ensure that the photocatalytic material powder is evenly dispersed in the organic material. The stirring speed and time can be adjusted according to the specific situation to avoid excessive foam or bubbles. In addition, in order to further improve the uniformity of the dispersion of the photocatalytic material in the organic material, an ultrasonic disperser can be used to ultrasonically treat the mixed liquid. The vibration of the ultrasonic wave helps to break the agglomeration between the powder particles and make it more evenly dispersed in the liquid matrix. Alternatively, the mixed liquid is stirred at a constant temperature at a certain temperature, which helps to promote the interaction and combination between the photocatalytic material and the organic material. The constant temperature can be selected according to the characteristics of the organic material and the requirements of the photocatalytic material.

[0051] In a possible implementation, the photocatalytic material is a transparent material, that is, it has a high light transmittance, which can avoid adverse effects on the light emitted by the light-emitting functional layer. Optionally, the light transmittance of the photocatalytic material is greater than or equal to 90%. Exemplarily, the photocatalytic material can be titanium dioxide, zinc oxide, etc. of certain specific crystal forms, which have low absorption and scattering in the visible light range and can maintain a high light transmittance.

[0052] In addition, the photocatalytic material of transparent material doped into the organic encapsulation layer can also improve the color deviation of the display panel. Specifically, after adding the photocatalytic material to the organic encapsulation layer, the photocatalytic material acts as a tiny scattering center in the organic encapsulation layer, scattering the incident light (such as the light incident from the light-emitting functional layer to the organic encapsulation layer), so that part of the light is scattered out at different angles instead of directly passing through the organic encapsulation layer. The photocatalytic material can effectively improve the color deviation problem by enhancing the scattering effect, making the color more uniform and accurate. On the one hand, scattering makes the propagation path of light in the organic encapsulation layer longer and increases the interaction time between light and the material, which helps to balance the absorption and transmission of light of different wavelengths in the material and reduce the color deviation caused by absorption differences; on the other hand, scattering also makes the light emission angle more dispersed, weakening the influence of the light emission angle on the color, helping to maintain color consistency at different viewing angles and reduce color deviation caused by changes in viewing angle.

[0053] The organic material in the embodiments of the present disclosure refers to the printing material used in the related art to prepare the organic encapsulation layer by inkjet printing. For example, the printing material is liquid acrylate, epoxy resin, silicone resin and other materials. The embodiments of the present disclosure do not improve the composition, proportion, etc. of the organic material in the printing material. The main improvement is to dope the photocatalytic material into the printing material.

[0054] In specific implementation, before doping the organic material with the photocatalytic material, it is necessary to determine the doping ratio and specific surface area of ​​the photocatalytic material. This process requires the use of the relationship between the encapsulation failure time and various parameters of the photocatalytic material.

[0055] The encapsulation failure time T refers to the time from the completion of the display panel encapsulation to the encapsulation layer being unable to effectively protect the light-emitting functional layer, thereby causing the display panel to degrade in performance, malfunction, or even complete failure. The encapsulation failure time T is related to the adsorption amount and mass of the photocatalytic material. The adsorption amount of the photocatalytic material can be understood as the ability of the photocatalytic material to split water molecules under light conditions. The relationship between the two can be expressed as: T = K*x*m+B, where K and B are constants, T represents the encapsulation failure time, x represents the adsorption amount of the photocatalytic material per unit mass, and m represents the mass of the photocatalytic material doped per milliliter of organic material, which can also be understood as the doping ratio of the photocatalytic material in the organic material. It can be seen that the encapsulation failure time is positively correlated with the adsorption amount of the photocatalytic material per unit mass and the mass of the photocatalytic material. The encapsulation failure time can be extended and the encapsulation effect can be improved by selecting a photocatalytic material with a larger x value or increasing the doping amount of the photocatalytic material. It can be understood that the relationship between the encapsulation failure time T and the adsorption amount and doping ratio of the photocatalytic material can be obtained through actual testing.

[0056] Among them, the adsorption amount x of the photocatalytic material per unit mass has a certain relationship with its saturated adsorption amount and specific surface area, which can be expressed as: x = S*a, where S represents the specific surface area of ​​the photocatalytic material, a represents the saturated adsorption amount of the photocatalytic material, and the saturated adsorption amount a is an inherent property of the photocatalytic material, which represents the maximum amount that the photocatalytic material can adsorb under ideal conditions. It can be seen that the adsorption amount of the photocatalytic material per unit mass is positively correlated with the specific surface area and the saturated adsorption amount. For different photocatalytic materials, due to different specific surface areas and saturated adsorption amounts, the calculated adsorption amount of the photocatalytic material per unit mass is also different. The adsorption amount of the photocatalytic material per unit mass can usually be provided by the manufacturer of the photocatalytic material.

[0057] Based on the above analysis, the photocatalytic material in the embodiment of the present disclosure satisfies: T = K*S*a*m+B. According to the determined package failure time, the photocatalytic material with a suitable specific surface area and the doping ratio can be determined.

[0058] In specific implementation, it is necessary to comprehensively consider different types of photocatalytic materials and different doping ratios to determine the optimal photocatalytic material doping scheme. For example, the following method can be used to determine:

[0059] (1) Clarify the type of doped photocatalytic material and the possible doping ratio.

[0060] For example, as shown in Table 1, n photocatalytic materials are selected and m doping ratios are set. The photocatalytic material in each scheme can be either a single material or a composite material, and the photocatalytic materials in different schemes can have different specific surface areas.

[0061] (2) Measure the package failure time and color deviation performance under different doping schemes.

[0062] For example, when the photocatalytic material 1 is doped into the organic material according to the doping ratio 1, the organic encapsulation layer is prepared by the inkjet printing process, and the encapsulation failure time and color deviation performance are measured under standard test conditions, wherein the standard test conditions are, for example, the temperature of 85°C and the humidity of 85%. Similarly, the encapsulation failure time and color deviation performance corresponding to different doping schemes can be measured, and then the doping ratio and specific surface area of ​​the feasible photocatalytic material can be determined. In Table 1, Tnm represents the encapsulation failure time measured when the doping scheme is a combination of doping ratio m and photocatalytic material n, and Cnm represents the color deviation performance measured when the doping scheme is a combination of doping ratio m and photocatalytic material n.

[0063] Table 1 Doping scheme

[0064] Doping ratio 1 Doping ratio 2 ... Doping ratio m Photocatalytic materials 1 T11, C11 T12, C12 ... T1m, C1m Photocatalytic materials 2 T21, C21 T22, C22 ... T2m, C2m ... ... ... ... ... Photocatalytic materials Tn1, Cn1 Tn2, Cn2 ... Tnm、Cnm

[0065] Exemplarily, three specific doping schemes are used as examples to describe the improvement of encapsulation performance and color deviation when photocatalytic materials are doped into the organic encapsulation layer.

[0066] Scheme 1: After evaporating the first inorganic layer on the light-emitting functional layer of the substrate, doping the organic material with a specific surface area of ​​200 cm 2 / g of photocatalytic material, the doping ratio is 2mg / mL, an organic thin film layer is formed on the first inorganic layer by using the doped organic material through an inkjet printing process, the organic thin film layer is photocured by ultraviolet light to cure the organic thin film layer to form an organic encapsulation layer, and a second inorganic layer is evaporated on the organic encapsulation layer.

[0067] Solution 2: After evaporating the first inorganic layer on the light-emitting functional layer of the substrate, doping the organic material with a specific surface area of ​​300 cm 2 / g of photocatalytic material, the doping ratio is 2mg / mL, an organic thin film layer is formed on the first inorganic layer by using the doped organic material through an inkjet printing process, the organic thin film layer is photocured by ultraviolet light to cure the organic thin film layer to form an organic encapsulation layer, and a second inorganic layer is evaporated on the organic encapsulation layer.

[0068] Solution 3: After evaporating the first inorganic layer on the light-emitting functional layer of the substrate, doping the organic material with a specific surface area of ​​400 cm 2 / g of photocatalytic material, the doping ratio is 4mg / mL, an organic thin film layer is formed on the first inorganic layer by using the doped organic material through an inkjet printing process, the organic thin film layer is photocured by ultraviolet light to cure the organic thin film layer to form an organic encapsulation layer, and a second inorganic layer is evaporated on the organic encapsulation layer.

[0069] The display panels encapsulated by Scheme 1, Scheme 2 and Scheme 3 were subjected to reliability tests and color deviation tests, and the encapsulation failure time and color deviation performance of the display panels were measured. They were compared with the organic encapsulation layer without doping photocatalytic materials, and the improvement effect data of different schemes shown in Tables 2 and 3 were obtained.

[0070] Among them, Table 2 shows the color shift data corresponding to different schemes, and Scheme 0 represents a scheme in which the photocatalytic material is not doped in the organic material, and other conditions are the same as Schemes 1 to 3. It can be seen from Table 2 that after the photocatalytic material is doped in the organic material, the color shift of the display panel is improved to a certain extent, and the color shift at different angles is alleviated, and the color shift performance of Scheme 3 is better than that of Scheme 2, and the color shift performance of Scheme 2 is better than that of Scheme 1.

[0071] Table 2 Color shift performance of different solutions

[0072]

[0073] Table 3 shows the package failure time corresponding to different schemes. Scheme 0 indicates that the organic material is not doped with photocatalytic material, and other conditions are the same as schemes 1 to 3. As can be seen from Table 3, after the organic material is doped with photocatalytic material, the package failure time of the display panel is greatly improved. In scheme 1, the package failure time is increased from 120 to 137, with an improvement rate of 14%, in scheme 2, the package failure time is increased from 120 to 212, with an improvement rate of 77%, and in scheme 3, the package failure time is increased from 120 to 556, with an improvement rate of 460%.

[0074] Table 3 Packaging failure time of different solutions

[0075] plan Doping ratio Specific surface area Package failure time Solution 0 0 0 120 Solution 1 2 200 137 Solution 2 2 300 212 Solution 3 4 400 556

[0076] In a possible implementation, the doping ratio of the photocatalytic material in the organic material is 2-10 mg / mL, that is, 2-10 mg of the photocatalytic material powder is doped in every 1 mL of the organic material, and the specific surface area of ​​the photocatalytic material is greater than or equal to 200 m 2 / g and less than or equal to 400m 2 / g. It has been verified through experiments that when the specific surface area and doping ratio of the photocatalytic material are within the above range, the packaging performance of the display panel can be significantly improved without affecting the display performance of the display panel.

[0077] It is understandable that the embodiments of the present disclosure only schematically provide several doping schemes for photocatalytic materials, but other doping schemes may also be used in specific implementations.

[0078] Based on the same inventive concept, the second aspect of the present disclosure provides a method for preparing a display panel, please refer to Figure 2 , Figure 2 A flow chart of a method for preparing a display panel provided in an embodiment of the present disclosure, such as Figure 2 As shown, the following steps are included:

[0079] Step S101, providing a substrate.

[0080] Step S102 , forming a driving circuit layer, a light-emitting functional layer and a packaging layer in sequence on the substrate, wherein the packaging layer comprises an organic packaging layer, and the organic packaging layer is doped with a photocatalytic material.

[0081] Optionally, the step of forming the encapsulation layer includes:

[0082] (1) forming a first inorganic encapsulation layer on the light-emitting functional layer;

[0083] (2) forming an organic encapsulation layer on the first inorganic encapsulation layer;

[0084] (3) A second inorganic encapsulating layer is formed on the organic encapsulating layer.

[0085] Optionally, the step of forming the organic encapsulation layer includes: (1) inkjet printing an organic material doped with a photocatalytic material to form an organic thin film layer; and photocuring the organic thin film layer to form the organic encapsulation layer.

[0086] Optionally, the photocuring treatment of the organic thin film layer is specifically: photocuring the organic thin film layer by ultraviolet light. It is understandable that the light source used in the curing process can be determined according to actual needs, such as selecting a suitable light source according to the type of organic material and the type of photocatalytic material, and is not limited to ultraviolet light.

[0087] Please refer to Figure 3 , Figure 3 is a process flow chart corresponding to the method for preparing a display panel, such as Figure 3 As shown, the method for preparing the display panel includes the following stages:

[0088] (a) providing a substrate 10, on which a driving circuit layer 20 and a light-emitting functional layer 30 are formed, and depositing a first inorganic encapsulation layer 401 on the substrate 10, wherein the light-emitting functional layer 30 is as follows: Figure 3 As shown in the light-emitting units R, G, and B.

[0089] (b) Printing a layer of organic material on the first inorganic encapsulation layer 401 by inkjet printing to form an organic thin film layer, wherein the organic material is doped with a photocatalytic material.

[0090] (c) The organic thin film layer is cured by ultraviolet light to form an organic encapsulation layer 402. During the curing process, the photocatalytic material decomposes water molecules in the organic thin film layer. The schematic diagram of the photocatalytic material decomposing water molecules under ultraviolet light is shown in FIG. Figure 4 shown.

[0091] (d) Depositing a second inorganic encapsulation layer 403 on the organic encapsulation layer 402 .

[0092] Compared with the related art, the preparation method of the embodiment of the present disclosure, by doping the photocatalyst in the organic material, and preparing the organic encapsulation layer through printing and light curing process, on the one hand, the photocatalyst has a rich aperture structure, which can extend the water oxygen molecule transmission path and improve the water oxygen barrier performance of the organic encapsulation layer; on the other hand, during the curing process, the photocatalyst can decompose the water in the organic encapsulation layer, reduce the water content in the organic encapsulation layer, further improve the encapsulation effect of the organic encapsulation layer, and extend the life of the device. In addition, while improving the encapsulation performance, the embodiment of the present disclosure does not need to add a new process flow, and only needs to add the powdered photocatalytic material to the organic material, which has a high feasibility in the process.

[0093] It can be understood that the display panel in the embodiment of the present disclosure can not only be an organic light-emitting diode (OLED) display panel, but also can be set to other types according to actual needs. For example, the display panel can also be a quantum dot light emitting diode (QLED) or a micro light emitting diode (Micro LED).

[0094] It is obvious that the above embodiments of the present disclosure are merely examples for clearly illustrating the present disclosure, and are not limitations on the implementation methods of the present disclosure. For those skilled in the art, other different forms of changes or modifications can be made based on the above descriptions. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solutions of the present disclosure are still within the protection scope of the present disclosure.

Claims

1. A display panel, characterized in that: The invention comprises a substrate, a driving circuit layer, a light-emitting functional layer and a packaging layer which are sequentially stacked on the substrate, wherein the packaging layer comprises an organic packaging layer, and the organic packaging layer is doped with a photocatalytic material.

2. The display panel according to claim 1, characterized in that: The photocatalytic material is in powder form, has a porous structure and a specific surface area greater than 100 m 2 / g.

3. The display panel according to claim 1, characterized in that: The light transmittance of the photocatalytic material is greater than or equal to 90%.

4. The display panel according to claim 1, characterized in that: The photocatalytic material satisfies: T=K*S*a*m+B, wherein T represents the encapsulation failure time, S represents the specific surface area of ​​the photocatalytic material, m represents the mass of the photocatalytic material per milliliter of organic material, a represents the saturated adsorption amount of the photocatalytic material, and K and B are constants.

5. The display panel according to claim 1, characterized in that: The doping ratio of the photocatalytic material in the organic material is 2-10 mg / mL, and the specific surface area of ​​the photocatalytic material is greater than or equal to 200 m 2 / g and less than or equal to 400m 2 / g.

6. The display panel according to claim 1, characterized in that: The photocatalytic material includes at least one of titanium oxide, zinc oxide, indium oxide, bismuth oxide and tin oxide.

7. The display panel according to claim 1, characterized in that: The encapsulation layer further includes: a first inorganic encapsulation layer disposed on a side of the organic encapsulation layer close to the light-emitting functional layer and a second inorganic encapsulation layer disposed on a side away from the light-emitting functional layer.

8. The display panel according to claim 1, characterized in that: The organic encapsulation layer is prepared by inkjet printing and light curing.

9. A method for preparing a display panel, characterized in that: The following steps are involved: providing a substrate; A driving circuit layer, a light-emitting functional layer and a packaging layer are sequentially formed on the substrate, wherein the packaging layer comprises an organic packaging layer, and the organic packaging layer is doped with a photocatalytic material.

10. The method for preparing a display panel according to claim 9, characterized in that: The steps of forming an organic encapsulation layer include: Inkjet printing an organic material doped with a photocatalytic material to form an organic thin film layer; The organic thin film layer is photocured to form an organic encapsulation layer.

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