Display panel, method for manufacturing the same, and display device

Abstract

An embodiment of the present application provides a display panel, a manufacturing method thereof, and a display device. The display panel includes: a substrate; a pixel defining layer located on one side of the substrate and having pixel holes arranged in an array; an ink material structure located in the pixel holes and corresponding to the pixel holes; wherein, the difference between the long-axis flatness and the short-axis flatness of at least part of the ink material structure is not greater than a first threshold, and the first threshold is not less than 1% and not greater than 10%. The embodiment of the present application can effectively reduce the degree of premature evaporation of the ink solvent in the inkjet printing process by using the liquid sealing principle, reduce the possible Marangoni effect, and effectively improve the flatness of the target film layer. This not only helps to improve the device performance but also helps to achieve device thinning.

Description

Technical Field

[0001] This application relates to the field of display technologies. Specifically, this application relates to a display panel, a method for manufacturing the same, and a display device. Background Art

[0002] Inkjet printing is a liquid ink deposition technology with relatively high precision and efficiency. The inkjet printing technology is more compatible with the semiconductor manufacturing field. For example, in the processes of manufacturing display panels, solar cells, photodetectors, etc., the inkjet printing technology can overcome the difficulties in traditional manufacturing processes and improve cost-effectiveness.

[0003] However, existing inkjet printing technologies usually have defects such as large ink loss or insufficient flatness of the film layer obtained after inkjet printing, which affect the application and popularization of inkjet printing technologies. Summary of the Invention

[0004] In view of the shortcomings of the existing methods, this application proposes a display panel, a method for manufacturing the same, and a display device to solve the technical problem that existing inkjet printing technologies usually have defects such as large ink consumption or insufficient flatness of the film layer obtained after inkjet printing.

[0005] In a first aspect, an embodiment of this application provides a display panel, including:

[0006] A substrate;

[0007] A pixel defining layer, located on one side of the substrate, having pixel holes arranged in an array;

[0008] At least part of the ink material structure, located in the pixel holes and corresponding to the pixel holes;

[0009] Wherein, the difference between the long-axis flatness and the short-axis flatness of at least part of the ink material structure is not greater than a first threshold, and the first threshold is not less than 1% and not greater than 10%.

[0010] Optionally, the first threshold is not less than 1.5% and not greater than 5%.

[0011] Optionally, the difference between the long-axis flatness and the short-axis flatness of at least part of the ink material structure is not less than a second threshold, and the second threshold is not less than 0.5% and not greater than 0.8%.

[0012] Optionally, the difference between the distances from at least two ink material structures to the plane where the openings of the corresponding pixel holes are located is not greater than a third threshold, and the third threshold is not less than 13 nanometers and not greater than 20 nanometers.

[0013] Optionally, the ink material structure includes at least one of polyol, ether, and ethyl 4-methylbenzoate.

[0014] Optionally, the display panel further includes an inkjet residue layer;

[0015] The inkjet residue layer is located on at least part of the pore wall and / or at least part of the pore bottom of the pixel hole.

[0016] Optionally, the inkjet residue layer includes at least one of cyclohexylbenzene, p-methoxytoluene, and 4-ethylbiphenyl; or at least one of methanol, isopropanol, and isopentyl benzoate.

[0017] Optionally, the ink material structure includes a hole injection layer, a hole transport layer, or a light-emitting layer.

[0018] Optionally, the display panel further includes an optical adjustment structure;

[0019] The optical adjustment structure is located between the substrate and the pixel definition layer and corresponds to the pixel hole;

[0020] The thickness of at least part of the optical adjustment structure is not equal.

[0021] In a second aspect, an embodiment of the present application provides a display device, including: the display panel provided in the first aspect.

[0022] In a third aspect, an embodiment of the present application provides a method for manufacturing a display panel, including:

[0023] Forming a pixel definition layer on one side of the substrate; the pixel definition layer has pixel holes arranged in an array;

[0024] Providing a liquid sealing material into at least part of the pixel holes;

[0025] Providing a target ink into the pixel holes;

[0026] Curing the target ink and separating at least part of the liquid sealing material from the target ink in the pixel holes to obtain an ink material structure, and the difference between the major axis flatness and the minor axis flatness of at least part of the ink material structure is not greater than a first threshold;

[0027] Wherein, the volatility of the liquid sealing material is greater than that of the target ink, the density of the liquid sealing material is less than that of the target ink, and the liquid sealing material is immiscible with the target ink.

[0028] Optionally, if the target ink includes a polyol or an ether material, the liquid sealing material includes at least one of cyclohexylbenzene, p-methoxytoluene, and 4-ethylbiphenyl;

[0029] If the target ink includes ethyl 4-methylbenzoate material, the liquid sealing material includes at least one of methanol, isopropanol, and isopentyl benzoate.

[0030] Optionally, the volume ratio of the liquid sealing material to the target ink is not less than 1:9 and not greater than 3:7.

[0031] The beneficial technical effects brought by the technical solution provided in the embodiment of the present application include:

[0032] By using the liquid sealing principle, the premature volatilization of the ink solvent in the inkjet printing process can be effectively reduced, the possible Marangoni effect can be reduced, and the flatness of the target film layer can be effectively improved. This not only helps to improve the device performance but also helps to realize the thinning of the device. In addition, by using the liquid sealing principle, there is no need to prepare a Dummy area on the substrate, which is beneficial to reducing the consumption of expensive ink. The cost of the liquid sealing material is much lower than that of the ink, and the production cost can be effectively reduced.

[0033] Specifically, the density of the liquid sealing material selected during the inkjet printing process is less than that of the target ink, and it can cover the upper layer of the target ink to inhibit the volatilization of the ink solvent; the liquid sealing material is immiscible with the target ink and is not likely to react with the target ink, ensuring the effectiveness of the target ink; the volatility of the liquid sealing material is greater than that of the target ink, which is beneficial to reducing the possible influence of the liquid sealing material on the film morphology of the solidified target ink.

[0034] The additional aspects and advantages of the present application will be partially given in the following description, and these will become obvious from the following description or will be understood through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The above and / or additional aspects and advantages of the present application will become obvious and easy to understand from the following description of the embodiments in conjunction with the drawings, where:

[0036] Figure 1 is a schematic flowchart of a method for manufacturing a display panel provided by an embodiment of the present application;

[0037] Figure 2 is a schematic diagram of a film layer structure after preparing a pixel defining layer on one side of a substrate in a method for manufacturing a display panel provided by an embodiment of the present application;

[0038] Figure 3 is a schematic diagram of a film layer structure after spraying a liquid sealing material into at least some pixel holes and spraying a target ink into the pixel holes in a method for manufacturing a display panel provided by an embodiment of the present application;

[0039] Figure 4 is a schematic diagram of a display panel provided by an embodiment of the present application;

[0040] Figure 5 is a schematic diagram of another display panel provided by an embodiment of the present application;

[0041] Figure 6A comparison diagram of the major axis morphology curves of the ink material structure in a specific display panel provided by an embodiment of the present application and the major axis morphology curves of the ink material structure in the display panel in the prior art;

[0042] Figure 7 A comparison diagram of the minor axis morphology curves of the ink material structure in a specific display panel provided by an embodiment of the present application and the minor axis morphology curves of the ink material structure in the display panel in the prior art.

[0043] In the figure:

[0044] 1 - Liquid sealing material; 2 - Target ink;

[0045] 10 - Display panel; 11 - Substrate; 12 - Pixel defining layer; 12a - Pixel hole; 13 - Ink material structure; 14 - Optical adjustment structure. Detailed implementation manners

[0046] The embodiments of the present application will be described below with reference to the accompanying drawings in the present application. It should be understood that the implementation manners described below in conjunction with the accompanying drawings are exemplary descriptions for explaining the technical solutions of the embodiments of the present application, and do not constitute limitations on the technical solutions of the embodiments of the present application.

[0047] Those skilled in the art of the present technology can understand that, unless specifically stated otherwise, the singular forms "a", "an", "the" and "said" used herein may also include the plural forms. It should be further understood that the term "including" used in the specification of the present application means the presence of the described features, integers, steps, operations, elements and / or components, but does not exclude the presence of other features, information, data, steps, operations, elements, components and / or combinations thereof supported by the art of the present technology. The term "and / or" used herein means at least one of the items defined by the term. For example, "A and / or B" can be implemented as "A", or implemented as "B", or implemented as "A and B".

[0048] To make the objectives, technical solutions and advantages of the present application clearer, the embodiments of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0049] First, several terms related to the present application will be introduced and explained:

[0050] Major axis flatness: The percentage of the pixel size in the major axis direction corresponding to a predetermined height range upward (or downward from the highest point of the center height) from the lowest point of the center height of the major axis of the pixel to the major axis opening size of the pixel hole. Optionally, the predetermined height can be 10 nm - 15 nm. For example: the predetermined height is 10 nm, 12 nm.

[0051] Minor axis flatness: The percentage between the pixel size along the minor axis corresponding to a predetermined height range from the lowest point of the central height of the minor axis of the pixel (or from the highest point of the central height downward) to the minor axis opening size of the pixel hole. Optionally, the predetermined height can be 10 nm - 15 nm. For example: the predetermined height is 10 nm, 12 nm.

[0052] Optionally, the long axis direction can be parallel to the data line direction, and the short axis direction can be parallel to the scanning line direction.

[0053] Optionally, the long axis direction can be along the long side direction of the pixel, and the short axis direction can be along the short side direction of the pixel.

[0054] The R & D idea of this application includes: During the process of preparing a display panel using inkjet printing technology, the printing nozzle can be controlled to spray ink of corresponding materials onto the substrate according to the target film layer being prepared. For example, during the preparation of OLED (Organic Light - Emitting Diode), the inkjet materials can include at least one of hole injection layer (HIL) ink, hole transport layer (HTL) ink, or emission layer (EML) ink, etc.

[0055] However, there is a phenomenon of solvent evaporation in the ink sprayed into the pixel holes on the substrate, which will induce the Marangoni effect of the ink, form a coffee ring in the pixel holes, resulting in a decrease in the flatness of the target film layer, and further causing the film thickness flatness of the entire substrate to deteriorate, affecting the device performance.

[0056] It can be considered to add a Dummy area at the edge of the pixel holes on the substrate to reduce the evaporation of the ink solvent in the pixel holes, but it cannot completely solve the problem of ink solvent evaporation, and printing in the Dummy area will also increase the consumption of ink, causing unnecessary waste of expensive ink and increasing production costs.

[0057] The display panel, its manufacturing method, and the display device provided by this application aim to solve the above - mentioned technical problems in the prior art.

[0058] The following uses specific embodiments to elaborate in detail on the technical solution of this application and how the technical solution of this application solves the above - mentioned technical problems. It should be noted that the following embodiments can refer to, draw on, or combine with each other. For the same terms, similar features, and similar implementation steps in different embodiments, they will not be described repeatedly.

[0059] The embodiment of this application provides a method for manufacturing a display panel. The schematic flow chart of this manufacturing method is as Figure 1 shown, including steps S101 - S104:

[0060] S101: Form a pixel defining layer on one side of the substrate; the pixel defining layer has pixel holes arranged in an array. Then perform step S102 or S103.

[0061] Optionally, this step S101 can adopt the following specific process: deposit a pixel defining material on one side of the substrate 11, then coat a photoresist on the pixel defining material, pattern the photoresist so that the photoresist forms a pattern corresponding to the distribution of the subsequent pixel holes 12a, and use the patterned photoresist as a mask to etch the pixel defining material to obtain a pixel defining layer 12 with pixel holes 12a arranged in an array. The schematic diagram of the film layer structure after performing this step S101 is as Figure 2 shown.

[0062] S102: Spray a sealing material into at least some of the pixel holes. For example: spray a liquid sealing material into at least some of the pixel holes. Then perform step S104.

[0063] Optionally, this step S102 can use an inkjet printing device to spray the liquid sealing material 1 into at least some of the pixel holes 12a of the pixel defining layer 12, that is, into the pixel holes 12a where the ink material structure 13 needs to be fabricated.

[0064] S103: Provide a target ink into the pixel holes. For example: spray a target ink into the pixel holes. Then perform step S104.

[0065] Optionally, this step S103 can also use an inkjet printing device to spray the target ink 2 into at least some of the pixel holes 12a of the pixel defining layer 12, that is, into the pixel holes 12a where the ink material structure 13 needs to be fabricated.

[0066] The schematic diagram of the film layer structure after performing the above steps S102 and S103 is as Figure 3 shown, and a layered state where the target ink 2 is at the bottom and the liquid sealing material 1 is at the top is formed in the pixel holes. The liquid sealing material 1 can form a liquid sealing effect on the target ink 2 to inhibit the volatilization of the ink solvent.

[0067] S104: Cure the target ink and separate at least some of the liquid sealing material from the target ink to obtain an ink material structure in the pixel holes, and the difference between the long-axis flatness and the short-axis flatness of at least some of the ink material structures is not greater than a first threshold, and the first threshold is not less than 1% and not greater than 10%.

[0068] The schematic diagram of the film layer structure after performing this step S104 is as Figure 4 shown.

[0069] Optionally, this step S104 can adopt a vacuum pumping process to separately pump away the solvents in the liquid sealing material 1 and the target ink 2 to obtain a cured ink material structure 13 in the pixel holes 12a.

[0070] In steps S101 - S104, the volatility of the liquid - sealing material 1 is greater than that of the target ink 2, the density of the liquid - sealing material 1 is less than that of the target ink 2, and the liquid - sealing material 1 is immiscible with the target ink 2.

[0071] In this embodiment, through steps S101 - S104, it is possible to effectively reduce the degree of premature evaporation of the ink solvent in the ink - jet printing process by using the liquid - sealing principle, reduce the possible Marangoni effect, and effectively improve the flatness of the target film layer. This not only helps to improve the device performance but also facilitates the thinning of the device. In addition, by using the liquid - sealing principle, there is no need to prepare a Dummy area on the substrate 11, which is beneficial to reducing the consumption of expensive ink. The cost of the liquid - sealing material 1 is much lower than that of the ink, which can effectively reduce the production cost.

[0072] Specifically, the density of the liquid - sealing material 1 selected during the ink - jet printing process is less than that of the target ink 2, and it can cover the upper layer of the target ink 2 to inhibit the evaporation of the ink solvent; the liquid - sealing material 1 is immiscible with the target ink 2 and is not likely to react with the target ink 2, ensuring the effectiveness of the target ink 2; the volatility of the liquid - sealing material 1 is greater than that of the target ink 2, which is beneficial to reducing the possible impact of the liquid - sealing material 1 on the film morphology of the solidified target ink 2.

[0073] In one example, after step S101 is completed, step S102 is executed first, and then step S103 is executed. That is, the liquid - sealing material 1 is first sprayed into the pixel hole 12a, and then the target ink 2 is sprayed into the pixel hole 12a. Since the density of the target ink 2 is greater than that of the liquid - sealing material 1, after the target ink 2 enters the pixel hole 12a, it will automatically sink, while the liquid - sealing material 1 will automatically float, forming a layered state with the liquid - sealing material 1 on the upper layer and the target ink 2 on the lower layer, achieving the liquid - sealing effect of the liquid - sealing material 1 on the target ink 2 in the pixel hole 12a.

[0074] In another example, after step S101 is completed, step S103 is executed first, and then step S102 is executed. That is, the target ink 2 is first sprayed into the pixel hole 12a, and then the liquid - sealing material 1 is sprayed into the pixel hole 12a. Since the density of the target ink 2 is greater than that of the liquid - sealing material 1, after the liquid - sealing material 1 enters the pixel hole 12a, it will float on the target ink 2, forming a layered state with the liquid - sealing material 1 on the upper layer and the target ink 2 on the lower layer, achieving the liquid - sealing effect of the liquid - sealing material 1 on the target ink 2 in the pixel hole 12a.

[0075] In yet another example, after performing step S101, steps S102 and S103 are performed simultaneously. That is, the liquid encapsulation material 1 and the target ink 2 are respectively sprayed into the pixel hole 12a at the same time. Since the density of the target ink 2 is greater than that of the liquid encapsulation material 1, after the target ink 2 enters the pixel hole 12a, it will automatically sink, while the liquid encapsulation material 1 will automatically float, forming a layered state with the liquid encapsulation material 1 on top and the target ink 2 at the bottom, achieving the liquid encapsulation effect of the liquid encapsulation material 1 on the target ink 2 in the pixel hole 12a. It should be noted that this example requires an inkjet printing device with relatively high precision to implement. Specifically, the inkjet printing device needs to have two nozzles that can spray the same pixel hole 12a simultaneously.

[0076] In some possible implementation manners, if the target ink 2 includes a polyol or an ether material, the liquid encapsulation material 1 includes at least one material selected from cyclohexylbenzene, p-methoxytoluene, and 4-ethylbiphenyl.

[0077] In this embodiment, the target ink 2 including a polyol or an ether material can be used to prepare a hole injection layer. The liquid encapsulation material 1 is selected from at least one of cyclohexylbenzene, p-methoxytoluene, and 4-ethylbiphenyl, which can meet the liquid encapsulation requirements for the polyol or ether material.

[0078] Optionally, when the liquid encapsulation material 1 includes one material selected from cyclohexylbenzene, p-methoxytoluene, and 4-ethylbiphenyl, after the separation in step S104, the residual probability of the liquid encapsulation material 1 in the pixel hole 12a is extremely low.

[0079] In some possible implementation manners, if the target ink 2 includes 4-methylbenzoic acid ethyl ester material, the liquid encapsulation material 1 includes at least one material selected from methanol, isopropanol, and isoamyl benzoate.

[0080] In this embodiment, the target ink 2 including 4-methylbenzoic acid ethyl ester material can be used to prepare a hole transport layer or a light-emitting layer. The liquid encapsulation material 1 is selected from at least one of methanol, isopropanol, and isoamyl benzoate, which can meet the liquid encapsulation requirements for the 4-methylbenzoic acid ethyl ester material.

[0081] Optionally, when the liquid sealant material 1 is a mixed material including at least two of methanol, isopropanol, and isoamyl benzoate, or when the liquid sealant material 1 is a mixed material including at least two of cyclohexylbenzene, p-methoxytoluene, and 4-ethylbiphenyl, after the separation in step S104, the liquid sealant material 1 may have a lower residual probability in the pixel hole 12a. This is because, by using any of the aforementioned mixed materials for the liquid sealant material 1, a slower volatility than that of a single material can be obtained, which is conducive to reducing the thickness of the liquid sealant material 1 on the upper layer of the target ink 2 in the pixel hole 12a on the premise of ensuring the liquid sealing effect, that is, it is beneficial to reduce the amount of the liquid sealant material 1 used, especially applicable to the scenario where the available space above the target ink 2 in the pixel hole 12a is insufficient.

[0082] In some possible implementation manners, the volume ratio of the liquid sealant material 1 to the target ink 2 is not less than 1:9 and not greater than 3:7.

[0083] In one example, when the liquid sealant material 1 is a mixed material including at least two of methanol, isopropanol, and isoamyl benzoate, or when the liquid sealant material 1 is a mixed material including at least two of cyclohexylbenzene, p-methoxytoluene, and 4-ethylbiphenyl, the volume ratio of the liquid sealant material 1 to the target ink 2 is not less than 1:9. By using the aforementioned mixed materials for the liquid sealant material 1, the boiling point is increased and the volatility is relatively lower, so the amount of the liquid sealant material 1 used can be appropriately reduced to reduce the probability or degree of over-inhibiting the evaporation of the ink solvent in the target ink 2.

[0084] In another example, when the liquid sealant material 1 includes one of methanol and isopropanol, the volume ratio of the liquid sealant material 1 to the target ink 2 is not greater than 3:7. By using the aforementioned single material for the liquid sealant material 1, the volatility is relatively higher, so the amount of the liquid sealant material 1 used can be appropriately increased to ensure sufficient inhibition effect on the evaporation of the ink solvent in the target ink 2.

[0085] Based on the same inventive concept, an embodiment of the present application provides a display panel 10, and the schematic structural diagram of the display panel 10 is as Figure 4 shown, including: a substrate 11, a pixel defining layer 12, and an ink material structure 13.

[0086] The pixel defining layer 12 is located on one side of the substrate 11 and has pixel holes 12a arranged in an array.

[0087] At least part of the ink material structure 13 is located in the pixel hole 12a and corresponds to the pixel hole 12a.

[0088] Wherein, the difference between the long-axis flatness and the short-axis flatness of at least part of the ink material structure 13 is not greater than a first threshold, and the first threshold is not less than 1% and not greater than 10%.

[0089] It should be noted that the first threshold is a reference value for defining flatness, specifically used to evaluate the flatness of the inner film layer structure of a single pixel hole 12a. The smaller the first threshold, the more stringent the degree of defining flatness, and vice versa.

[0090] In this embodiment, the flatness of the ink material structure 13 within a single pixel hole 12a of the display panel 10 is higher than that of the corresponding film layer in a conventional display panel 10, which can obtain better device performance and also reduce the thickness of the subsequent flat layer, that is, it is beneficial to realize the thinning of the display panel 10.

[0091] It can be understood that in order to achieve a higher flatness of the display panel 10, the display panel 10 provided in the embodiments of the present application can be obtained by using any one of the display panel preparation methods described in detail above.

[0092] The display panel obtained by using any one of the display panel preparation methods described in detail above can achieve a higher-precision flatness. Specifically, in some possible implementation manners, the first threshold is not less than 1.5% and not greater than 5%.

[0093] Considering that in the prior art, if the long-axis flatness and short-axis flatness of the ink material structure are made absolutely the same, that is, the difference is 0, it may be necessary to overcome great technical difficulties or pay a great cost. However, in the display panel obtained by using any one of the display panel preparation methods described in detail above in the present application, the difference between the long-axis flatness and short-axis flatness of at least part of the ink material structure 13 can be made much lower than that in the prior art. Specifically, in some possible implementation manners, the difference between the long-axis flatness and short-axis flatness of at least part of the ink material structure is not less than a second threshold, and the second threshold is not less than 0.5% and not greater than 0.8%.

[0094] In one example, as Figure 6 and Figure 7 shown, compared with the long-axis morphology curve and short-axis morphology curve (i.e., "before improvement") of the ink material structure in the display panel in the prior art, the long-axis morphology curve and short-axis morphology curve (i.e., "after improvement") of the ink material structure in the display panel obtained by using any one of the display panel preparation methods described in detail above in the present application are significantly flatter.

[0095] The long-axis flatness before improvement is about 91%, the short-axis flatness is about 51%, and the difference between them is about 40%; while after improvement, it can reach a long-axis flatness of about 95%-97% and a short-axis flatness of about 90%-96%, and the difference is about 1%-7%. For example: as Figure 6 and Figure 7 shown, after improvement, it can reach a long-axis flatness of about 97% and a short-axis flatness of about 96%, and the difference is about 1%.

[0096] In some possible embodiments, the difference in the distances from at least two ink material structures 13 to the plane where the openings of the corresponding pixel holes 12a are located is not greater than a third threshold value, and the third threshold value is not less than 13 nm and not greater than 20 nm.

[0097] It should be noted that the third threshold value is another reference value for defining flatness, specifically used to evaluate the flatness between the corresponding film layer structures in different pixel holes 12a. The smaller the third threshold value, the more stringent the degree of defining flatness, and vice versa.

[0098] In this embodiment, the flatness of the ink material structures 13 as a whole in different pixel holes 12a of the display panel 10 is higher than that of the corresponding film layers in a conventional display panel 10. Better device performance can also be obtained, and the thickness of the subsequent flat layer can be reduced, which is conducive to realizing the thinning of the display panel 10.

[0099] In one example, the difference in the distances from at least two ink material structures 13 to the plane where the openings of the corresponding pixel holes 12a are located is not greater than 15 nm, while the difference in the distances from two ink material structures 13 obtained by using the prior art to the plane where the openings of the corresponding pixel holes 12a are located may reach 25 - 30 nm at the lowest.

[0100] In some possible embodiments, the ink material structure 13 includes at least one of polyol, ether, and ethyl 4-methylbenzoate.

[0101] In one example, the ink material structure 13 includes polyol or an ether material, and a hole injection layer can be formed.

[0102] In another example, the ink material structure 13 includes ethyl 4-methylbenzoate material, and a hole transport layer or a light-emitting layer can be formed.

[0103] In some possible embodiments, the display panel 10 further includes an inkjet residue layer (not shown in the figure).

[0104] The inkjet residue layer is located on at least part of the pore wall and / or at least part of the pore bottom of the pixel hole 12a.

[0105] In this embodiment, the inkjet residue layer may be the liquid seal material 1 remaining in the pixel hole 12a during the preparation process using the liquid seal principle.

[0106] Optionally, the inkjet residue layer includes at least one of cyclohexylbenzene, p-methoxytoluene, and 4-ethylbiphenyl; or at least one of methanol, isopropanol, and isoamyl benzoate.

[0107] In some possible embodiments, the ink material structure 13 includes a hole injection layer, a hole transport layer, or a light-emitting layer. These OLED functional film layers can all be prepared by inkjet printing technology, for example, by using any of the preparation methods of the display panel 10 based on the liquid encapsulation principle elaborated in detail above.

[0108] In some possible embodiments, as Figure 5 shown, the display panel 10 further includes an optical adjustment structure 14;

[0109] The optical adjustment structure 14 is located between the substrate 11 and the pixel defining layer 12 and corresponds to the pixel hole 12a;

[0110] The thicknesses of at least part of the optical adjustment structure 14 are not equal.

[0111] In this embodiment, the thicknesses of at least part of the optical adjustment structure 14 are not equal, so that the adjustment of light can be achieved by affecting the refractive index of light, the transmittance of light, etc., to meet the output light requirements of the display panel 10.

[0112] Based on the same inventive concept, an embodiment of the present application provides a display device, including: any one of the display panels 10 provided in the above embodiments.

[0113] In this embodiment, since the display device includes any one of the display panels 10 provided in the foregoing embodiments, its implementation principle and beneficial effects are similar and will not be elaborated here.

[0114] Optionally, the display device may include a mobile phone, a tablet computer, a mobile terminal, an e-book, and so on.

[0115] Applying the embodiments of the present application can at least achieve the following beneficial effects:

[0116] 1. It can effectively reduce the degree of premature evaporation of the ink solvent in the inkjet printing process by using the liquid encapsulation principle, reduce the possible Marangoni effect, and effectively improve the flatness of the target film layer. This not only helps to improve the device performance but also helps to achieve device thinning.

[0117] 2. By using the liquid encapsulation principle, there is no need to prepare a Dummy area on the substrate 11, which is beneficial to reducing the consumption of expensive ink. The cost of the liquid encapsulation material 1 is much lower than that of the ink, and the production cost can be effectively reduced.

[0118] Those skilled in the art of the present application can understand that the various operations, methods, steps, measures, and solutions in the processes discussed in the present application can be alternated, changed, combined, or deleted. Further, other steps, measures, and solutions in the various operations, methods, and processes discussed in the present application can also be alternated, changed, rearranged, decomposed, combined, or deleted. Further, those in the prior art that have steps, measures, and solutions in the various operations, methods, and processes disclosed in the present application can also be alternated, changed, rearranged, decomposed, combined, or deleted.

[0119] In the description of the present application, the directions or positional relationships indicated by the words "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are the exemplary directions or positional relationships based on the drawings, which are for the convenience of describing or simplifying the embodiments of the present application, rather than indicating or implying that the indicated device or component must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application.

[0120] The terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, unless otherwise stated, the meaning of "a plurality" is two or more.

[0121] It should be understood that although the steps in the flowchart of the drawings are shown sequentially as indicated by the arrows, the implementation order of these steps is not limited to the order indicated by the arrows. Unless clearly stated herein, in some implementation scenarios of the embodiments of the present application, the steps in each process can be executed in other orders according to requirements. Moreover, some or all of the steps in each flowchart may include multiple sub-steps or multiple stages based on the actual implementation scenarios. Some or all of these sub-steps or stages can be executed at the same time or at different times. In the scenario where the execution times are different, the execution order of these sub-steps or stages can be flexibly configured according to requirements, and the embodiments of the present application do not limit this.

[0122] The above are only some implementation manners of the present application. It should be noted that for those of ordinary skill in the art of the present technology, without departing from the technical concept of the solution of the present application, adopting other similar implementation means based on the technical idea of the present application also belongs to the protection scope of the embodiments of the present application.

Claims

1. A method for preparing a display panel, characterized in that Comprising: Forming a pixel defining layer on one side of a substrate; The pixel defining layer has pixel holes arranged in an array; Providing a liquid sealant material into at least part of the pixel holes; Providing a target ink into the pixel holes; Curing the target ink, and separating at least part of the liquid sealant material from the target ink, to obtain an ink material structure in the pixel holes, and the difference between the major axis flatness and the minor axis flatness of at least part of the ink material structure is not greater than a first threshold, the first threshold is not less than 1% and not greater than 10%; Wherein, the major axis flatness is the percentage between the pixel size in the major axis direction corresponding to a predetermined height range from the lowest point of the major axis center height of the pixel upward or from the highest point of the center height downward and the major axis opening size of the pixel hole; the minor axis flatness is the percentage between the pixel size in the minor axis direction corresponding to a predetermined height range from the lowest point of the minor axis center height of the pixel upward or from the highest point of the center height downward and the minor axis opening size of the pixel hole; Wherein, the volatility of the liquid sealant material is greater than that of the target ink, the density of the liquid sealant material is less than that of the target ink, and the liquid sealant material is immiscible with the target ink.

2. The preparation method according to claim 1, wherein If the target ink includes a polyol or an ether material, then the liquid sealant material includes at least one of cyclohexylbenzene, p-methoxytoluene, and 4-ethylbiphenyl; If the target ink includes ethyl 4-methylbenzoate material, then the liquid sealant material includes at least one of methanol, isopropanol, and isoamyl benzoate.

3. The preparation method according to claim 2, characterized in that, The volume ratio of the liquid sealant material to the target ink is not less than 1:9 and not greater than 3:

7.

4. A display panel prepared by the method according to any one of claims 1-3, characterized in that, Comprising: A substrate; A pixel defining layer, located on one side of the substrate, having pixel holes arranged in an array; At least part of the ink material structure, located in the pixel holes and corresponding to the pixel holes; Wherein, the difference between the major axis flatness and the minor axis flatness of at least part of the ink material structure is not greater than a first threshold, the first threshold is not less than 1% and not greater than 10%; Wherein, the major axis flatness is the percentage between the pixel size in the major axis direction corresponding to a predetermined height range from the lowest point of the major axis center height of the pixel upward or from the highest point of the center height downward and the major axis opening size of the pixel hole; the minor axis flatness is the percentage between the pixel size in the minor axis direction corresponding to a predetermined height range from the lowest point of the minor axis center height of the pixel upward or from the highest point of the center height downward and the minor axis opening size of the pixel hole.

5. The display panel according to claim 4, wherein The first threshold is not less than 1.5% and not greater than 5%.

6. The display panel according to claim 4, wherein The difference between the major axis flatness and the minor axis flatness of at least part of the ink material structure is not less than a second threshold, the second threshold is not less than 0.5% and not greater than 0.8%.

7. The display panel according to claim 4, wherein The difference in the distances from at least two of the ink material structures to the plane where the openings of the corresponding pixel holes are located is not greater than a third threshold, the third threshold is not less than 13 nanometers and not greater than 20 nanometers.

8. The display panel according to claim 4, wherein The ink material structure includes at least one of a polyol, an ether, and ethyl 4-methylbenzoate.

9. The display panel according to claim 4, wherein The display panel further includes an inkjet residue layer; The inkjet residue layer is located on at least part of the hole walls and / or at least part of the hole bottoms of the pixel holes.

10. The display panel according to claim 9, wherein, The inkjet residue layer includes at least one of cyclohexylbenzene, p-methoxytoluene, and 4-ethylbiphenyl; or at least one of methanol, isopropanol, and isopentyl benzoate.

11. The display panel according to any one of claims 4-10, characterized in that, The ink material structure includes a hole injection layer, a hole transport layer, or a light-emitting layer.

12. The display panel according to any one of claims 4-10, characterized in that, The display panel further includes an optical adjustment structure; The optical adjustment structure is located between the substrate and the pixel defining layer and corresponds to the pixel holes; The thicknesses of at least part of the optical adjustment structure are not equal.

13. A display device, characterized in that, Comprising: The display panel according to any one of claims 4-12 above.

Images