Display panel and preparation method and system thereof

Abstract

This application provides a display panel and its fabrication method and system. The display panel includes: a substrate, comprising a substrate and a TFT stack formed on the surface of the substrate; the TFT stack forms a barrier structure through its own thickness difference; the area enclosed by the barrier structure is an effective display area; an inorganic barrier film layer conformally covers the surface of the TFT stack; the surface of the inorganic barrier film layer at the corresponding position of the barrier structure constitutes a leveling boundary that contacts the organic functional ink; at least one surface of the leveling boundary is provided with a photoresponsive variable wettability functional layer, which is hydrophobic under visible light irradiation and highly hydrophilic under ultraviolet light irradiation; an inkjet-printed organic functional layer is provided within the effective display area. This application introduces a photoresponsive variable wettability functional layer at the leveling boundary to make the edge morphology of the inkjet-printed organic functional layer smooth, thereby reducing the risk of progressive black spots and film peeling in subsequent process steps and improving the packaging yield and long-term reliability of the display panel.

Description

Technical Field

[0001] This application relates to the field of display panel technology, and in particular to a display panel and its preparation method and system. Background Technology

[0002] In the fabrication of thin-film encapsulation (TFE) or planarization layers for high-end display panels (such as OLEDs), inkjet printing (IJP) is widely used due to its advantages such as high material utilization and suitability for large-size and flexible substrates. One of the key steps in this process is printing organic functional inks (such as planarization layer inks) within the effective display area (AA area) defined by dams or trenches. The ink droplets need to be leveled, dried, and cured within the AA area to form a uniform and flat film layer.

[0003] The leveling position, final morphology, and thickness uniformity of inkjet-printed films are greatly limited by the wettability of the printing substrate (usually CVD1 or other underlying films). If the substrate wettability is too high (too hydrophilic), the ink is prone to climbing up the slope or even overflowing during leveling, leading to overflow defects and causing short circuits or reliability issues in subsequent processes. Conversely, if the substrate wettability is too low (too hydrophobic), the ink droplets are difficult to spread, easily resulting in uneven film thickness and edge shrinkage, forming display inhomogeneity (Mura) defects. As the demand for thinner IJP film layers in display panels becomes increasingly urgent in pursuit of better optical and touch performance, and to avoid Mura, the process tends to increase substrate wettability. However, this makes leveling control and morphology optimization at the edges of the IJP film extremely difficult. Excessive wettability can lead to an increased incidence of ink anomalies at the leveling boundary, inducing encapsulation failures such as progressive black spots (GDS) and film peeling in subsequent processes or use. Currently, there is no way to solve the problems in existing inkjet printing and packaging processes for display panels, such as difficulties in leveling control, poor edge morphology, and various defects such as overflow, mura, GDS, and peeling caused by the fixed wettability of the leveling boundary area. Summary of the Invention

[0004] The purpose of this application is to provide a display panel and its fabrication method and system. In this display panel, the inkjet-printed organic functional layer has smooth edges, which helps reduce the risk of progressive black spots and film peeling in subsequent processes, significantly improving the packaging yield and long-term reliability of the display panel. The specific technical solution is as follows:

[0005] The first aspect of this application provides a display panel, including:

[0006] A substrate includes a substrate and a TFT stack formed on the surface of the substrate; the TFT stack forms a barrier structure including enclosures and / or trenches through the thickness difference of its own film layers; the area enclosed by the barrier structure is an effective display area;

[0007] An inorganic barrier film layer is conformally covered on the surface of the TFT stack;

[0008] The surface of the inorganic barrier film layer at the corresponding position of the barrier structure forms a leveling boundary that contacts the organic functional ink. At least one surface of the leveling boundary is provided with a photoresponsive variable wettability functional layer. The photoresponsive variable wettability functional layer is hydrophobic under visible light irradiation and highly hydrophilic under ultraviolet light irradiation.

[0009] An inkjet-printed organic functional layer is provided within the effective display area.

[0010] In some embodiments of this application, the surface of the leveling boundary includes the sloping surface and / or top surface of the inorganic barrier film layer at the corresponding position of the enclosure, and / or the inner wall of the inorganic barrier film layer at the corresponding position of the trench.

[0011] In some embodiments of this application, the raw materials of the photoresponsive variable wettability functional layer include at least one of fluoroazobenzene polymer, spiropyran, and fumonisin anhydride;

[0012] The fluorinated azobenzene polymer is selected from at least one of 2,6,2',6'-tetrafluoroazobenzene acrylate alkyl copolymers, C4-C8 perfluoroalkylazobenzene methacrylate copolymers with side chains, o-fluoroazobenzene alkyl acrylate homopolymers, and tetrafluorobenzene ring azovinyl copolymers; the number average molecular weight of the fluorinated azobenzene polymer is 3000-50000.

[0013] The spiropyran is selected from at least one of 6-nitro-1',3',3'-trimethylindoline spirobenzopyran, 8-methoxy-6-nitro-1',3',3'-trimethylindoline spirobenzopyran, and 6-bromo-1',3',3'-trimethylindoline spirobenzopyran;

[0014] The spermicidal anhydride is selected from at least one of 2,5-dimethylfuranyl spermicidal anhydride, phenylmonofuranyl-substituted spermicidal anhydride, bisthiophene-spermicidal anhydride, 3-phenyleneethyl-2-(4-pyridinylmethylene) spermicidal ester, and trifluoromethylindolyl spermicidal imide.

[0015] In some embodiments of this application, the thickness of the photoresponsive variable wettability functional layer is 30nm-10000nm.

[0016] In some embodiments of this application, the photoresponsive variable wettability functional layer is prepared using an initiation-based chemical vapor deposition process or a partitioned inkjet printing process.

[0017] In some embodiments of this application, the wavelength of the visible light is 400nm-700nm; the wavelength of the ultraviolet light is 315nm-400nm.

[0018] The second aspect of this application provides a method for manufacturing the display panel described in the first aspect of this application, comprising the steps of:

[0019] Provide substrate,

[0020] The substrate includes a substrate and a TFT stack formed on the surface of the substrate; a barrier structure including barriers and / or trenches is formed by the thickness difference of the stacked film layers of the TFT stack itself, and the barrier structure encloses an effective display area;

[0021] An inorganic barrier film is conformally deposited on the surface of the TFT stack;

[0022] A hydrophobic, photoresponsive, variable wettability functional layer is formed on at least one surface of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the barrier structure; organic functional ink is printed into the effective display area.

[0023] The effective display area is selectively irradiated with ultraviolet light to cure the organic functional ink and form an inkjet-printed organic functional layer.

[0024] The photoresponsive variable wettability functional layer is irradiated with ultraviolet light to transform it into a highly hydrophilic state, so that the edge of the organic functional ink comes into contact with the highly hydrophilic photoresponsive variable wettability functional layer to form a smooth edge morphology.

[0025] In some embodiments of this application, forming a photoresponsive variable wettability functional layer in a hydrophobic state specifically includes the steps of: depositing a photoresponsive variable wettability functional layer on at least one surface of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the barrier structure using an initiation chemical vapor deposition process; and irradiating the photoresponsive variable wettability functional layer with visible light to transform it into a hydrophobic state.

[0026] In some embodiments of this application, forming a hydrophobic photoresponsive variable wettability functional layer and printing organic functional ink specifically includes the following steps: using a partitioned inkjet printing process to print organic functional ink into the effective display area, and spraying photoresponsive variable wettability functional ink onto at least one surface of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the barrier structure to form the photoresponsive variable wettability functional layer; and using visible light irradiation to transform the photoresponsive variable wettability functional layer into a hydrophobic state.

[0027] In some embodiments of this application, a wettability gradient is formed in the photoresponse-variable wettability functional layer by adjusting at least one of the intensity, duration and scanning path of the ultraviolet light irradiating the fence and / or ditch slope.

[0028] The third aspect of this application provides a fabrication system for preparing the display panel described in the first aspect of this application, comprising: a unit for depositing the photoresponse variable wettability functional layer, a specific wavelength light source chamber for regulating wettability, and a photocuring unit capable of selective irradiation by region and wavelength; wherein the light source chamber is capable of outputting 400nm-700nm visible light and 315nm-400nm ultraviolet light.

[0029] The beneficial effects of this application are:

[0030] This application provides a display panel and its fabrication method and system. By introducing a photoresponsive variable wettability functional layer on at least one surface of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the barrier structure, the on-demand and dynamic switching of wettability in the key steps of inkjet printing (IJP) process is realized (hydrophobic barrier before leveling, hydrophilic optimization before curing). This solves the contradiction that a single wettability cannot meet the needs of different processes from a time perspective. It can effectively reduce the risk of progressive black spots (GDS) and film peeling caused by overflow and abnormal edge morphology, and significantly improve the packaging yield and long-term reliability of the display panel. In addition, the photoresponsive variable wettability functional layer has excellent adhesion and high mechanical strength to the interface of the underlying film layer, and does not bring additional failure risks. The photoresponsive variable wettability functional layer can be integrated into the existing production line through initiation chemical vapor deposition (iCVD) or partition inkjet printing (IJP) process without making disruptive changes to the overall process flow. Among them, the IJP partition printing scheme has a relatively low implementation cost and does not require the removal of the functional layer in the future.

[0031] Of course, implementing any product or method of this application does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other embodiments can be obtained based on these accompanying drawings.

[0033] Figure 1 This is a schematic diagram illustrating the principle of controlling the spreading of organic functional inks in inkjet printing when using iCVD to prepare a photoresponsive variable wettability functional layer in one embodiment of this application.

[0034] Figure 2 This is a schematic diagram illustrating the principle of controlling the spreading of organic functional inks during inkjet printing when preparing a photoresponsive variable wettability functional layer using a partitioned inkjet printing process, as described in another embodiment of this application.

[0035] Figure 3A This is a schematic diagram of the process of using DTD as a barrier structure, preparing a photoresponsive variable wettability functional layer by iCVD, and printing organic functional ink into the effective display area after being irradiated with visible light. The diagram shows the organic functional ink spreading and contacting the hydrophobic photoresponsive variable wettability functional layer. After the hydrophobic photoresponsive variable wettability functional layer suppresses ink overflow, the printing leveling stage ends.

[0036] Figure 3B In another embodiment of this application, only the enclosure serves as a blocking structure. The process of preparing a photoresponsive variable wettability functional layer by iCVD and printing organic functional ink into the effective display area after being irradiated with visible light is shown. The diagram shows the organic functional ink spreading and contacting the hydrophobic photoresponsive variable wettability functional layer. After the hydrophobic photoresponsive variable wettability functional layer suppresses ink overflow, the printing leveling stage ends.

[0037] Figure 3C In another embodiment of this application, only the grooves serve as the blocking structure. The process of preparing a photoresponsive variable wettability functional layer by iCVD and printing organic functional ink into the effective display area after being irradiated with visible light is shown. The diagram shows the organic functional ink spreading and contacting the photoresponsive variable wettability functional layer in a hydrophobic state. After the hydrophobic photoresponsive variable wettability functional layer suppresses ink overflow, the printing leveling stage ends.

[0038] Figure 4A In another embodiment of this application, a schematic diagram is shown of the process of wettability transformation and edge trimming of organic functional ink after iCVD fabrication of a photoresponsive variable wettability functional layer and printing of organic functional ink using DTD as a barrier structure and ultraviolet light irradiation. It shows that when ultraviolet light is turned on, the photoresponsive variable wettability functional layer changes from a hydrophobic state to a hydrophilic state, the edge of the organic functional ink is pulled by hydrophilic force to release stress, and then the morphology of the inkjet printed organic functional layer is finally determined.

[0039] Figure 4BIn another embodiment of this application, only the enclosure serves as a barrier structure. After preparing a photoresponsive variable wettability functional layer using iCVD and printing organic functional ink, a schematic diagram of the wettability transformation and edge trimming of the organic functional ink under ultraviolet light irradiation is shown. It shows that when ultraviolet light is turned on, the photoresponsive variable wettability functional layer changes from a hydrophobic state to a hydrophilic state. The edge of the organic functional ink is pulled by hydrophilic force to release stress, and then the morphology of the inkjet-printed organic functional layer is finally determined.

[0040] Figure 4C In another embodiment of this application, only the grooves serve as the blocking structure. After the photoresponsive variable wettability functional layer is prepared by iCVD and organic functional ink is printed, the wettability changes and the edge trimming of the organic functional ink is shown in the schematic diagram. It shows that when the ultraviolet light is turned on, the photoresponsive variable wettability functional layer changes from a hydrophobic state to a hydrophilic state. The edge of the organic functional ink is pulled by the hydrophilic force to release stress, and then the morphology of the inkjet printed organic functional layer is finally determined.

[0041] Figure 5A In another embodiment of this application, a DTD is used as a barrier structure. A partitioned inkjet printing process is used to prepare a photoresponsive variable wettability functional layer. The inkjet printing process under visible light irradiation is shown in the schematic diagram. The organic functional ink spreads and contacts the hydrophobic photoresponsive variable wettability functional layer. After the hydrophobic photoresponsive variable wettability functional layer suppresses ink overflow, the printing leveling stage ends.

[0042] Figure 5B In another embodiment of this application, only the enclosure serves as a blocking structure. A photoresponsive variable wettability functional layer is prepared using a partitioned inkjet printing process. The inkjet printing process under visible light irradiation is shown in the schematic diagram. The diagram shows the photoresponsive variable wettability functional layer in a hydrophobic state after the organic functional ink spreads and contacts the hydrophobic state of the photoresponsive variable wettability functional layer. The printing leveling stage ends after the hydrophobic state of the photoresponsive variable wettability functional layer suppresses ink overflow.

[0043] Figure 5C In another embodiment of this application, only the grooves serve as the blocking structure. A schematic diagram of the inkjet printing process under visible light irradiation is used to prepare a photoresponsive variable wettability functional layer using a partitioned inkjet printing process. The diagram shows the photoresponsive variable wettability functional layer in a hydrophobic state after the organic functional ink spreads and contacts the hydrophobic state of the photoresponsive variable wettability functional layer. The printing leveling stage ends after the hydrophobic state of the photoresponsive variable wettability functional layer suppresses ink overflow.

[0044] Figure 6AIn another embodiment of this application, a schematic diagram is shown of the process of wettability transformation and edge trimming of organic functional ink under ultraviolet light irradiation after the photoresponse variable wettability functional layer is prepared by using a partition inkjet printing process with DTD as a barrier structure. It shows that when ultraviolet light is turned on, the photoresponse variable wettability functional layer changes from a hydrophobic state to a hydrophilic state, and the edge of the organic functional ink is pulled by hydrophilic force to release stress, and then the morphology of the inkjet printed organic functional layer is finally determined.

[0045] Figure 6B In another embodiment of this application, only the enclosure serves as a blocking structure. After the photoresponsive variable wettability functional layer is prepared by partition inkjet printing process, the wettability changes and the edge trimming of the organic functional ink is carried out under ultraviolet light irradiation. The diagram shows that when ultraviolet light is turned on, the photoresponsive variable wettability functional layer changes from a hydrophobic state to a hydrophilic state. The edge of the organic functional ink is pulled by hydrophilic force to release stress, and then the morphology of the inkjet printed organic functional layer is finally determined.

[0046] Figure 6C In another embodiment of this application, only the grooves serve as the blocking structure. After the photoresponsive variable wettability functional layer is prepared by partition inkjet printing process, the wettability changes and the edge trimming of the organic functional ink is carried out under ultraviolet light irradiation. The diagram shows that when ultraviolet light is turned on, the photoresponsive variable wettability functional layer changes from a hydrophobic state to a hydrophilic state. The edge of the organic functional ink is pulled by hydrophilic force to release stress, and then the morphology of the inkjet printed organic functional layer is finally determined. Detailed Implementation

[0047] The technical solutions of this application will be clearly and completely described below with reference to the embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on this application are within the scope of protection of this application.

[0048] The first aspect of this application provides a display panel, such as Figure 1 and Figure 2 As shown, it includes:

[0049] A substrate includes a substrate and a TFT stack formed on the surface of the substrate; the TFT stack forms a barrier structure including enclosures and / or trenches through the thickness difference of its own film layers; the area enclosed by the barrier structure is an effective display area;

[0050] An inorganic barrier film layer is conformally covered on the surface of the TFT stack;

[0051] The inorganic barrier film layer surface at the corresponding position of the barrier structure forms a leveling boundary that contacts the organic functional ink. At least one surface of the leveling boundary is provided with a photoresponsive variable wettability functional layer. The photoresponsive variable wettability functional layer is hydrophobic (low wettability) under visible light irradiation and highly hydrophilic (high wettability) under ultraviolet (UV) light irradiation.

[0052] An inkjet-printed organic functional layer is provided within the effective display area.

[0053] Figure 1 This is a schematic diagram illustrating the principle of controlling the spreading of organic functional inks in inkjet printing when using iCVD to fabricate photoresponsive variable wettability functional layers; from Figure 1 As can be seen, the photoresponsive variable wettability functional layer is prepared using the iCVD process. This layer simultaneously covers the inorganic barrier film surface at corresponding positions on the inner wall of the trench, the side wall of the enclosure, and the top surface of the enclosure. Under visible light irradiation, the photoresponsive variable wettability functional layer exhibits low wettability, which can block and constrain the uncured organic functional ink printed by inkjet printing, inhibiting ink overflow across the enclosure. After switching to ultraviolet light irradiation, the photoresponsive variable wettability functional layer changes to high wettability, which can pull the ink edge and modify the edge morphology of the inkjet printed organic functional layer, realizing dynamic control of wettability throughout the printing-curing process.

[0054] Figure 2 This is a schematic diagram illustrating the principle of controlling the spreading of organic functional inks during the fabrication of photoresponsive variable wettability functional layers using a partitioned inkjet printing process; from Figure 2 As can be seen, the photoresponse-variable wettability functional layer is prepared using the IJP partition inkjet printing process. The photoresponse-variable wettability functional layer is set on the surface of the inorganic barrier film layer at the corresponding positions of the inner wall of the trench and the side wall of the enclosure. Under visible light irradiation, the photoresponse-variable wettability functional layer exhibits low wettability, which can block and constrain the uncured organic functional ink printed by inkjet printing, and inhibit the ink from overflowing across the enclosure. After switching to ultraviolet light irradiation, the photoresponse-variable wettability functional layer changes to high wettability, which can pull the ink edge and modify the edge morphology of the inkjet printed organic functional layer, realizing dynamic control of wettability throughout the printing-curing process.

[0055] The TFT stack described in this application is a collection of multilayer stacked thin-film transistors disposed on the substrate surface. This application does not particularly limit the specific structure of the TFT stack, but it may include at least two layers such as a gate conductive layer, a gate insulating layer, a semiconductor active layer, an interlayer insulating dielectric layer, and a source-drain metal layer.

[0056] This application utilizes the patterning of different film layers within a TFT stack and the thickness differences between the film layers to naturally form raised barriers and / or recessed trenches on the substrate surface after the multilayer films are stacked, thereby constructing a barrier structure for defining the effective display area. An inorganic barrier film layer is conformally deposited on the surface of the TFT stack, which already has the stepped morphology of barriers and / or trenches, extending along the stepped morphology of the TFT stack, thus obtaining a corresponding leveling boundary on the surface of the inorganic barrier film layer, providing space for the photoresponse variable wettability functional layer. The inventors believe that patterned etching of the inorganic barrier film layer can also be used to form a barrier structure including raised barriers and / or recessed trenches.

[0057] The barrier (Dam) described in this application refers to a raised structure formed in the non-effective display area (e.g., the border area) of the display panel, used to block and limit the flow of functional inks (such as organic planarization layers, thin film encapsulation layers, etc.) in its preset effective display area (AA area).

[0058] The trench described in this application refers to a recessed structure located at the edge of the effective display area or in the pixel definition layer (PDL) in certain designs of display panels (especially some high-end or flexible OLED structures) to accommodate and confine functional inks; unlike the raised dam, the trench utilizes the sidewalls and bottom of its recess to control the leveling boundary of the ink.

[0059] When the barrier structure described in this application includes both fencing and trenches, it is also called a DTD fencing structure, namely a Dam / Trench / Dam fencing trench structure.

[0060] In the DTD enclosure structure described in this application, the number of trenches can be one or more, preferably one to four.

[0061] The DTD structure described in this application can significantly improve the leveling boundary control capability of IJP; in this application, IJP (Ink Jet Printing) refers to inkjet printing, which is a non-contact patterning technology that forms a film layer by precisely depositing functional ink droplets onto a designated position on the substrate.

[0062] The active area (AA) mentioned in this application refers to the area on the screen actually used to display images.

[0063] The hydrophobic state (low wettability) described in this application refers to a contact angle > 90°; the highly hydrophilic state (high wettability) described in this application refers to a contact angle < 30°.

[0064] This application introduces a photoresponsive variable wettability functional layer at the leveling boundary, enabling on-demand and dynamic switching of wettability in key IJP process steps (i.e., during the inkjet printing leveling stage, the leveling boundary of the enclosure area becomes low wettability to prevent organic functional ink overflow; in the subsequent UV curing stage, the leveling boundary of the enclosure area becomes high wettability to optimize the edge morphology of the inkjet-printed organic functional layer), resolving the contradiction that a single wettability cannot meet the needs of different processes from a temporal perspective. The display panel of this application exhibits a smooth edge morphology of the inkjet-printed organic functional layer, effectively reducing the risk of progressive black spots (GDS) and film peeling caused by overflow and abnormal edge morphology, significantly improving the packaging yield and long-term reliability of the display panel; furthermore, the photoresponsive variable wettability functional layer has excellent adhesion and high mechanical strength at the interface with the underlying film layer, without introducing additional failure risks.

[0065] The overflow mentioned in this application refers to the phenomenon where ink droplets from inkjet printing overflow beyond the dam boundary due to excessive wettability, causing defects such as pattern contamination or short circuits. The GDS (Growing DarkSpot) mentioned in this application refers to progressive dark spots, a type of encapsulation failure mode, where black spot defects on the display panel gradually expand during subsequent use or environmental testing. The peeling mentioned in this application refers to the separation phenomenon between different film layers caused by insufficient adhesion or stress mismatch.

[0066] In some embodiments of this application, the surface of the leveling boundary includes the sloping surface and / or top surface of the inorganic barrier film layer at the corresponding position of the enclosure, and / or the inner wall of the inorganic barrier film layer at the corresponding position of the trench. This application provides a photoresponsive variable wettability functional layer on at least one surface of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the barrier structure, particularly on the sloping surface, where the wettability can be reversibly switched under different wavelengths of light.

[0067] In some embodiments of this application, the raw materials for the photoresponsive variable wettability functional layer include at least one of a fluoroazobenzene polymer, spiropyran, and fumonisin anhydride.

[0068] In this application, the raw materials of the photoresponsive variable wettability functional layer include not only photoresponsive molecular materials (at least one of fluoroazobenzene polymer, spiropyran and fentanyl anhydride), but also other related raw materials that achieve the inventive purpose of this application (to achieve reversible switching of wettability under different wavelengths of light), such as photopolymerizable monomers, photoinitiators, etc., which are all conventional raw materials in the art.

[0069] In this application, when the fluorinated azobenzene polymer is irradiated with visible light, the azobenzene units in the polymer are in a trans isomer-dominant state, at which time the surface energy of the polymer decreases and it exhibits a hydrophobic state (low wettability); when the fluorinated azobenzene polymer is irradiated with ultraviolet light, the azobenzene units in the polymer undergo photoisomerization from trans to cis, at which time the surface energy of the polymer increases and it transforms into a highly hydrophilic state (high wettability).

[0070] In this application, both spiropyran and spirocyanate anhydride can undergo reversible structural changes and wettability alterations under different wavelengths of light; however, spiropyran may have insufficient fatigue resistance.

[0071] It should be noted that the wettability of the leveling boundary can also be changed by using thermally responsive polymers (such as poly-N-isopropylacrylamide) through local heating / cooling; however, the speed of thermal response regulation may be slow, and precise local temperature control is difficult.

[0072] In addition, the wettability of the leveling boundary can also be changed by using electrochemical or solvent atmosphere triggering methods. For example, a polymer layer containing electroactive ions can be prepared and its surface energy can be changed by applying voltage, but this requires the introduction of electrode structures, which makes the process complex; the solvent atmosphere is difficult to control and may contaminate the production line.

[0073] In some embodiments of this application, the fluorinated azobenzene polymer is selected from at least one of 2,6,2',6'-tetrafluoroazobenzene acrylate alkyl copolymers, C4-C8 perfluoroalkylazobenzene methacrylate copolymers with side chains, o-fluoroazobenzene alkyl acrylate homopolymers, and tetrafluorobenzene ring azovinyl copolymers; the number average molecular weight of the fluorinated azobenzene polymer is 3000-50000.

[0074] In some embodiments of this application, the spiropyran is selected from at least one of 6-nitro-1',3',3'-trimethylindoline spiropyran, 8-methoxy-6-nitro-1',3',3'-trimethylindoline spiropyran, and 6-bromo-1',3',3'-trimethylindoline spiropyran.

[0075] In some embodiments of this application, the spermicidal anhydride is selected from at least one of 2,5-dimethylfuranyl spermicidal anhydride, phenylmonofuranyl-substituted spermicidal anhydride, bisthiophene-spermicidal anhydride, 3-phenyleneethyl-2-(4-pyridinylmethylene) spermicidal ester, and trifluoromethylindolyl spermicidal imide.

[0076] In some embodiments of this application, the thickness of the photoresponse-variable wettability functional layer is 30nm-10000nm. In this application, the thickness of the photoresponse-variable wettability functional layer can be 30nm, 50nm, 100nm, 200nm, 300nm, 400nm, 500nm, 600nm, 885nm, 1000nm, 1169nm, 1454nm, 1739nm, 2024nm, 2309nm, 2594nm, 2879nm, 3163nm, 3448nm, 3733nm, 4018nm, 43... The range is defined by 0.3nm, 4588nm, 4873nm, 5157nm, 5442nm, 5727nm, 6012nm, 6297nm, 6582nm, 6867nm, 7151nm, 7436nm, 7721nm, 8006nm, 8291nm, 8576nm, 8861nm, 9145nm, 9430nm, 9715nm, 10000nm, or any two of these values. This application controls the thickness of the photoresponsive variable wettability functional layer within the above range, which helps to suppress ink overflow during the leveling process in the inkjet printing stage. When in contact with the edge of the cured inkjet-printed organic functional layer in the AA area, the interface can be optimized, edge stress can be released, and a smoother transition morphology can be obtained.

[0077] In some embodiments of this application, the photoresponsive variable wettability functional layer is prepared using an initiation-based chemical vapor deposition process or a partitioned inkjet printing process.

[0078] The initiated chemical vapor deposition (iCVD) process described in this application refers to an innovative polymer thin film preparation technology that can directly generate ultrathin and uniform polymer coatings on the substrate surface through vapor deposition.

[0079] The partitioned inkjet printing process (improved IJP partitioned printing process) described in this application refers to the use of inkjet printing equipment with dual printheads or multi-material printing capabilities, in which two inks can be printed sequentially or nearly simultaneously.

[0080] In some embodiments of this application, the wavelength of the visible light is 400nm-700nm. In this application, the wavelength of the visible light can be 400nm, 450nm, 500nm, 550nm, 600nm, 650nm, 700nm, or a range formed by any two of these values. This application does not particularly limit the irradiation duration and intensity of the visible light, as long as the inventive objective of this application is achieved. For example, the irradiation duration of the visible light is >1ms, and the irradiation intensity is >0.05mW / cm². 2 .

[0081] In some embodiments of this application, the wavelength of the ultraviolet light is 315nm-400nm. In this application, the wavelength of the ultraviolet light can be 315nm, 320nm, 330nm, 340nm, 350nm, 360nm, 370nm, 380nm, 390nm, 400nm, or a range formed by any two of these values. This application does not particularly limit the irradiation duration and intensity of the ultraviolet light, as long as the inventive objective of this application is achieved. For example, the irradiation duration of the ultraviolet light is >3s, and the irradiation intensity is >0.3mW / cm². 2 .

[0082] It should be noted that if a photoresponsive variable wettability functional layer is not prepared separately, but instead photoresponsive molecules (such as fluoroazobenzene polymers) are directly mixed as additives into the constituent materials of the Dam / Trench / Dam enclosure structure (if the enclosure structure itself is formed by photolithography or printing from organic materials), the overall wettability can be made to be variable after the enclosure structure is formed by light irradiation. Although this simplifies the preparation process, it may affect the structural strength of the Dam / Trench / Dam enclosure structure itself or its adhesion to other film layers; and the additives may migrate, affecting long-term stability.

[0083] The second aspect of this application provides a method for manufacturing the display panel described in the first aspect of this application, comprising the steps of:

[0084] S1: A substrate is provided, the substrate including a substrate and a TFT stack formed on the surface of the substrate; a barrier structure including a barrier and / or a trench is formed by the thickness difference of the stacked film layers of the TFT stack itself, the barrier structure enclosing an effective display area;

[0085] An inorganic barrier film is conformally deposited on the surface of the TFT stack;

[0086] S2: A hydrophobic, photoresponsive, variable wettability functional layer is formed on at least one surface of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the barrier structure; organic functional ink is printed into the effective display area.

[0087] S3: Selectively irradiate the effective display area with ultraviolet light to cure the organic functional ink and form an inkjet printed organic functional layer;

[0088] S4: The photoresponse variable wettability functional layer is irradiated with ultraviolet light to transform it into a highly hydrophilic state, so that the edge of the organic functional ink comes into contact with the highly hydrophilic photoresponse variable wettability functional layer to form a smooth edge morphology.

[0089] This application does not particularly limit the specific method for forming a TFT stack on the substrate surface to obtain a barrier structure in S1, as long as it can achieve the inventive purpose of this application; this application does not particularly limit the specific structure of the TFT stack, for example, it may include at least two layers such as a gate conductive layer, a gate insulating layer, a semiconductor active layer, an interlayer insulating dielectric layer, and a source-drain metal layer. This application utilizes the thickness difference and pattern steps between different layers of the TFT stack, and directly constructs a barrier structure including a barrier and / or trench morphology through the thickness difference of each stacked layer, without the need for additional separate film formation and photolithography etching to create the barrier and / or trench; the subsequently deposited inorganic barrier film conformally covers the TFT stack and the barrier and / or trench morphology formed thereon.

[0090] This application does not impose any particular limitation on the method of conformally depositing an inorganic barrier film layer on the surface of the TFT stack in S1, as long as the inventive purpose of this application can be achieved. For example, a chemical vapor deposition (CVD) process can be used to conformally deposit an inorganic barrier film layer on the surface (the entire surface) of the TFT stack.

[0091] This application does not impose any particular restrictions on subsequent processing after S4. Processing can be carried out according to actual needs. For example, the entire display panel can be treated with visible light or heat to restore the photoresponse variable wettability functional layer to the inverse hydrophobic state, or to maintain the hydrophilic state according to the requirements of subsequent processes.

[0092] In some embodiments of this application, S2, forming a photoresponsive variable wettability functional layer in a hydrophobic state specifically includes the steps of: depositing a photoresponsive variable wettability functional layer on at least one surface of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the barrier structure using an initiation chemical vapor deposition (iCVD) process; and irradiating the photoresponsive variable wettability functional layer with visible light to transform it into a hydrophobic state.

[0093] In this application, during the iCVD deposition process of S2, the effective display area can be blocked by a mask, and only the leveling boundary is exposed for the deposition of the photoresponsive variable wettability functional layer.

[0094] In one embodiment of this application, such as Figure 3A The diagram shows a process of printing organic functional ink into the effective display area using a DTD as a barrier structure, iCVD to prepare a photoresponsive variable wettability functional layer, and then irradiating it with visible light. The diagram shows the organic functional ink spreading and contacting the hydrophobic photoresponsive variable wettability functional layer, and the printing leveling stage ending after the hydrophobic photoresponsive variable wettability functional layer suppresses ink overflow.

[0095] like Figure 4AThe diagram shows the process of wettability transformation and edge trimming of the organic functional ink after iCVD fabrication of a photoresponsive variable wettability functional layer using a DTD as a barrier structure and printing organic functional ink, under ultraviolet light irradiation. It shows that when ultraviolet light is turned on, the photoresponsive variable wettability functional layer changes from a hydrophobic state to a hydrophilic state, and the edge of the organic functional ink is pulled by hydrophilic force to release stress, and then the morphology of the inkjet-printed organic functional layer is finally determined.

[0096] In one embodiment of this application, such as Figure 3B The diagram shows a process where an iCVD-prepared photoresponsive variable wettability functional layer is used as a barrier structure, and after being irradiated with visible light, organic functional ink is printed into the effective display area. The diagram shows the organic functional ink spreading and contacting the hydrophobic photoresponsive variable wettability functional layer. After the hydrophobic photoresponsive variable wettability functional layer suppresses ink overflow, the printing leveling stage ends.

[0097] like Figure 4B As shown, this diagram illustrates the process of wettability transformation and edge trimming of the organic functional ink after iCVD fabrication of a photoresponsive variable wettability functional layer and printing of organic functional ink using only a barrier structure as a blocking structure, under ultraviolet light irradiation. It shows that when ultraviolet light is turned on, the photoresponsive variable wettability functional layer changes from a hydrophobic state to a hydrophilic state, and the edge of the organic functional ink releases stress due to hydrophilic force, thereby finalizing the morphology of the inkjet-printed organic functional layer.

[0098] In one embodiment of this application, such as Figure 3C As shown, this is a schematic diagram of the process of printing organic functional ink into the effective display area after the iCVD fabrication of a photoresponsive variable wettability functional layer using only the groove as a blocking structure and after being irradiated with visible light. It shows the state at which the organic functional ink spreads and contacts the hydrophobic photoresponsive variable wettability functional layer, and the printing leveling stage ends after the hydrophobic photoresponsive variable wettability functional layer suppresses ink overflow.

[0099] like Figure 4C The diagram shows the process of wettability transformation and edge trimming of the organic functional ink after iCVD fabrication of a photoresponsive variable wettability functional layer using only trenches as a barrier structure and printing organic functional ink, under ultraviolet light irradiation. It shows that when ultraviolet light is turned on, the photoresponsive variable wettability functional layer changes from a hydrophobic state to a hydrophilic state, the edge of the organic functional ink is pulled by hydrophilic force to release stress, and then the morphology of the inkjet-printed organic functional layer is finally determined.

[0100] In some embodiments of this application, S2, forming a hydrophobic photoresponsive variable wettability functional layer and printing organic functional ink specifically includes the following steps: using a partitioned inkjet printing process, printing organic functional ink into the effective display area, and spraying photoresponsive variable wettability functional ink onto at least one surface of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the barrier structure to form the photoresponsive variable wettability functional layer; and using visible light irradiation to transform the photoresponsive variable wettability functional layer into a hydrophobic state.

[0101] In this application, the photoresponsive variable wettability functional ink of S2 may include: a photopolymerizable monomer, a photoinitiator, and a photoresponsive molecular material (at least one of a fluoroazobenzene polymer, spiropyran, and fumonisin anhydride).

[0102] This application does not impose any particular restrictions on the specific equipment used in the partitioned inkjet printing process in S2, as long as it can achieve the purpose of this invention. For example, an inkjet printing device with dual printheads or multi-material printing capabilities can be used; the first printhead uses the aforementioned photoresponsive variable wettability functional ink to accurately print on the slope of the barrier structure or other designated areas; the second printhead uses conventional organic functional ink to print on the AA area.

[0103] In one embodiment of this application, such as Figure 5A The diagram shows a schematic of the inkjet printing process under visible light irradiation, in which a DTD (Digital Response Tolerance) functional layer with photoresponse variable wettability is prepared using a partitioned inkjet printing process. The diagram shows the organic functional ink spreading and contacting the hydrophobic photoresponse variable wettability functional layer, and the state after the hydrophobic photoresponse variable wettability functional layer suppresses ink overflow, indicating the end of the printing leveling stage.

[0104] like Figure 6A The diagram shows the process of wettability transformation and edge trimming of organic functional inks under ultraviolet light irradiation after a photoresponsive variable wettability functional layer is prepared using a partitioned inkjet printing process with a DTD as the barrier structure. It shows that when ultraviolet light is turned on, the photoresponsive variable wettability functional layer changes from a hydrophobic state to a hydrophilic state, and the edge of the organic functional ink is pulled by hydrophilic force to release stress, and then the morphology of the inkjet-printed organic functional layer is finally determined.

[0105] In one embodiment of this application, such as Figure 5B The diagram shows the process of preparing a photoresponsive variable wettability functional layer using a partitioned inkjet printing process with only a barrier as a blocking structure, and the inkjet printing process under visible light irradiation. It shows the organic functional ink spreading and contacting the photoresponsive variable wettability functional layer in a hydrophobic state, and the state after the hydrophobic photoresponsive variable wettability functional layer suppresses ink overflow, at the end of the printing leveling stage.

[0106] like Figure 6B The diagram shows the process of wettability transformation and edge trimming of organic functional inks under ultraviolet light irradiation after a photoresponsive variable wettability functional layer is prepared using a partitioned inkjet printing process with only a barrier as a blocking structure. It shows that when ultraviolet light is turned on, the photoresponsive variable wettability functional layer changes from a hydrophobic state to a hydrophilic state, and the edge of the organic functional ink is pulled by hydrophilic force to release stress, and then the morphology of the inkjet-printed organic functional layer is finally determined.

[0107] In one embodiment of this application, such as Figure 5C The diagram shows the process of preparing a photoresponsive variable wettability functional layer using a partitioned inkjet printing process with only grooves as a blocking structure, and the inkjet printing process under visible light irradiation. It shows the photoresponsive variable wettability functional layer in a hydrophobic state after the organic functional ink spreads and contacts the hydrophobic state of the photoresponsive variable wettability functional layer, and the printing leveling stage ends after the hydrophobic state of the photoresponsive variable wettability functional layer suppresses ink overflow.

[0108] like Figure 6C The diagram shows the process of wettability transformation and edge trimming of organic functional ink under ultraviolet light after a photoresponsive variable wettability functional layer is prepared using a partitioned inkjet printing process with only grooves as a barrier structure. It shows that when ultraviolet light is turned on, the photoresponsive variable wettability functional layer changes from a hydrophobic state to a hydrophilic state, and the edge of the organic functional ink is pulled by hydrophilic force to release stress, and then the morphology of the inkjet-printed organic functional layer is finally determined.

[0109] In some embodiments of this application, in step S4, by adjusting at least one of the intensity, duration, and scanning path of the ultraviolet light irradiating the photoresponse-variable wettability functional layer at the slope of the enclosure and / or trench, a wettability gradient is formed in the photoresponse-variable wettability functional layer. It should be noted that the photoresponse-variable wettability functional layer at the slope of the enclosure and / or trench here refers to the photoresponse-variable wettability functional layer at the slope of the inorganic barrier film layer corresponding to the location of the enclosure and / or trench.

[0110] The wettability gradient described in this application refers to different wettability at different locations, such as gradually increasing hydrophilicity from the top of a slope to the bottom, or gradually decreasing hydrophilicity from the top of a slope to the bottom. Forming a wettability gradient in the photoresponsive variable wettability functional layer facilitates more precise guidance and control of the micro-flow and morphology of the organic functional ink in the AA area before curing in the edge region, achieving a better edge encapsulation effect.

[0111] In one embodiment of this application, the method for manufacturing a display panel includes the following steps:

[0112] S1: As Figure 3AAs shown, a substrate including a substrate and a TFT stack formed on the surface of the substrate is provided; a barrier structure (DTD barrier structure) including barriers and trenches is formed by the thickness difference of the film stack of the TFT stack itself, and the DTD barrier structure encloses the effective display area; an inorganic barrier film layer is conformally deposited on the surface (the entire surface) of the TFT stack using a chemical vapor deposition process.

[0113] S2: As Figure 3A As shown, an initiation chemical vapor deposition (iCVD) process is used to selectively deposit a photoresponsive wettability functional layer with a thickness of 30nm-10000nm containing a fluorinated azobenzene polymer on the surface (slope and top area) of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the DTD enclosure structure. During the deposition process, the AA area is blocked by a mask, and only the leveling boundary is exposed for deposition.

[0114] The panel is transferred to a pretreatment chamber equipped with a visible light source (wavelength 400nm-700nm); by irradiating with visible light, the azobenzene units in the fluorinated azobenzene polymer are in the trans isomer-dominated state. At this time, the polymer surface energy is low, and the photoresponsive variable wettability functional layer exhibits a hydrophobic state (low wettability).

[0115] The panel is transferred to the inkjet printer, where organic functional inks are precisely printed into the AA area under the protection of the hydrophobic DTD barrier structure. Due to the hydrophobic nature of the photoresponsive variable wettability functional layer on the surface of the DTD barrier structure, the overflow tendency of organic functional inks during the leveling process can be effectively suppressed.

[0116] S3: The panel is transferred to the UV curing chamber, where digital light processing (DLP) technology or a precision mask is used to selectively irradiate the organic functional ink in the effective display area with first ultraviolet light (such as 315nm-400nm), so that the organic functional ink is initially cured and formed into an inkjet printed organic functional layer; while the leveling boundary is masked, the wettability of the photoresponse variable wettability functional layer remains unchanged (still hydrophobic).

[0117] S4: Adjust the illumination mode and selectively irradiate the photoresponsive variable wettability functional layer with a second ultraviolet light (e.g., 315nm-400nm) to transform it into a highly hydrophilic state (or use broadband light to simultaneously irradiate the entire panel). The fluorinated azobenzene polymer in the photoresponsive variable wettability functional layer undergoes trans-to-cis photoisomerization under ultraviolet light irradiation, increasing its surface energy and transforming it into a hydrophilic state (high wettability). At this point, the edge of the cured inkjet-printed organic functional layer in the AA area contacts the surface of the hydrophilic photoresponsive variable wettability functional layer, optimizing the interface energy, which helps release edge stress and obtain a smooth transition morphology (e.g., ...). Figure 4A (as shown)

[0118] The entire display panel is subjected to final processing using visible light or heat to restore the photoresponse variable wettability functional layer to an inverse hydrophobic state, or to maintain a hydrophilic state according to subsequent process requirements.

[0119] In another embodiment of this application, the method for manufacturing the display panel includes the following steps:

[0120] S1: As Figure 5A As shown, a substrate including a substrate and a TFT stack formed on the surface of the substrate is provided; a barrier structure (DTD barrier structure) including barriers and trenches is formed by the thickness difference of the film stack of the TFT stack itself, and the DTD barrier structure encloses the effective display area; an inorganic barrier film layer is conformally deposited on the surface (the entire surface) of the TFT stack using a chemical vapor deposition process.

[0121] S2: Prepare a photoresponsive variable wettability functional ink containing a photopolymerizable monomer, a photoinitiator, and a fluorinated azobenzene polymer;

[0122] like Figure 5A As shown, partitioned inkjet printing (IJP) is performed using an inkjet printer with dual printheads or multi-material printing capabilities. The first printhead uses the aforementioned photoresponsive variable wettability functional ink to precisely print on the surface (sloping surface and top area) of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the DTD enclosure structure; the second printhead uses conventional organic functional ink to print on the AA area; the two inks can be printed sequentially or nearly simultaneously.

[0123] Irradiating the entire panel with visible light (wavelength 400nm-700nm) has two effects. First, it stabilizes the azobenzene units in the photoresponse-variable wettability functional ink at the leveling boundary in a trans-hydrophobic state, resulting in a low-wetting photoresponse-variable wettability functional layer with a thickness of 30nm-1000nm. Second, it may trigger a preliminary cross-linking reaction (if the ink formulation supports it).

[0124] S3: The panel is transferred to the UV curing chamber, where digital light processing (DLP) technology or a precision mask is used to selectively irradiate the organic functional ink in the effective display area with first ultraviolet light (such as 315nm-400nm), so that the organic functional ink is initially cured and formed into an inkjet printed organic functional layer; while the leveling boundary is masked, the wettability of the photoresponse variable wettability functional layer remains unchanged (still hydrophobic).

[0125] S4: Adjust the illumination mode and selectively irradiate the photoresponsive variable wettability functional layer with a second ultraviolet light (e.g., 315nm-400nm) to transform it into a highly hydrophilic state (or use broadband light to simultaneously irradiate the entire panel). The fluorinated azobenzene polymer in the photoresponsive variable wettability functional layer undergoes trans-to-cis photoisomerization under ultraviolet light irradiation, increasing its surface energy and transforming it into a hydrophilic state (high wettability). At this point, the edge of the cured inkjet-printed organic functional layer in the AA area contacts the surface of the hydrophilic photoresponsive variable wettability functional layer, optimizing the interface energy, which helps release edge stress and obtain a smooth transition morphology (e.g., ...). Figure 6A (as shown)

[0126] The entire display panel is subjected to final processing using visible light or heat to restore the photoresponse variable wettability functional layer to an inverse hydrophobic state, or to maintain a hydrophilic state according to subsequent process requirements.

[0127] In another embodiment of this application, the method for manufacturing the display panel includes the following steps:

[0128] S1: Provides a substrate including a substrate and a TFT stack formed on the surface of the substrate; forms a barrier structure (DTD barrier structure) including barriers and trenches through the thickness difference of the film layers stacked by the TFT stack itself, the DTD barrier structure enclosing the effective display area; conformally deposits an inorganic barrier film layer on the surface (the entire surface) of the TFT stack using a chemical vapor deposition process.

[0129] S2: Using initiated chemical vapor deposition (iCVD) technology, a photoresponsive wettability functional layer with a thickness of 1000nm-10000nm containing a fluorinated azobenzene polymer is selectively deposited on the surface (slope and top area) of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the DTD enclosure structure. During the deposition process, the AA area is blocked by a mask, and only the leveling boundary is exposed for deposition.

[0130] The panel is transferred to a pretreatment chamber equipped with a visible light source (wavelength 400nm-700nm); by irradiating with visible light, the azobenzene units in the fluorinated azobenzene polymer are in the trans isomer-dominated state. At this time, the polymer surface energy is low, and the photoresponsive variable wettability functional layer exhibits a hydrophobic state (low wettability).

[0131] The panel is transferred to the inkjet printer, where organic functional inks are precisely printed into the AA area under the protection of the hydrophobic DTD barrier structure. Due to the hydrophobic nature of the photoresponsive variable wettability functional layer on the surface of the DTD barrier structure, the overflow tendency of organic functional inks during the leveling process can be effectively suppressed.

[0132] S3: The panel is transferred to the UV curing chamber, where digital light processing (DLP) technology or a precision mask is used to selectively irradiate the organic functional ink in the effective display area with first ultraviolet light (such as 315nm-400nm), so that the organic functional ink is initially cured and formed into an inkjet printed organic functional layer; while the leveling boundary is masked, the wettability of the photoresponse variable wettability functional layer remains unchanged (still hydrophobic).

[0133] S4: Adjust the illumination mode and selectively irradiate the photoresponse variable wettability functional layer with a second ultraviolet light (e.g., 315nm-400nm). By controlling the illumination intensity, time, or scanning path of the second ultraviolet light irradiating the photoresponse variable wettability functional layer on the slope, a wettability gradient is formed on the slope (e.g., from the top of the slope to the bottom, the hydrophilicity gradually increases). This gradient wettability is beneficial for more precise guidance and control of the micro-flow and morphology of the organic functional ink in the AA area before curing in the edge region, so as to achieve the best edge encapsulation effect.

[0134] The edge of the inkjet-printed organic functional layer that has been cured in the AA region comes into contact with the surface of the hydrophilic, photoresponsive, and wettable functional layer, which optimizes the interface energy, helps to release edge stress, and obtains a smooth transition morphology.

[0135] The entire display panel is subjected to final processing using visible light or heat to restore the photoresponse variable wettability functional layer to an inverse hydrophobic state, or to maintain a hydrophilic state according to subsequent process requirements.

[0136] In another embodiment of this application, the method for manufacturing the display panel includes the following steps:

[0137] S1: Provides a substrate including a substrate and a TFT stack formed on the surface of the substrate; forms a barrier structure (DTD barrier structure) including barriers and trenches through the thickness difference of the film layers stacked by the TFT stack itself, the DTD barrier structure enclosing the effective display area; conformally deposits an inorganic barrier film layer on the surface (the entire surface) of the TFT stack using a chemical vapor deposition process.

[0138] S2: Prepare a photoresponsive variable wettability functional ink containing a photopolymerizable monomer, a photoinitiator, and a fluorinated azobenzene polymer;

[0139] Partition inkjet printing (IJP) is performed using an inkjet printer with dual printheads or multi-material printing capabilities. The first printhead uses the aforementioned photoresponsive variable wettability functional ink to precisely print on the surface (sloping surface and top area) of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the DTD enclosure structure. The second printhead uses conventional organic functional ink to print on the AA area. The two inks can be printed sequentially or nearly simultaneously.

[0140] Irradiating the entire panel with visible light (wavelength 400nm-700nm) has two effects. First, it stabilizes the azobenzene units in the photoresponse-variable wettability functional ink at the leveling boundary in a trans-hydrophobic state, resulting in a low-wetting photoresponse-variable wettability functional layer with a thickness of 30nm-10000nm. Second, it may trigger a preliminary cross-linking reaction (if the ink formulation supports it).

[0141] S3: The panel is transferred to the UV curing chamber, where digital light processing (DLP) technology or a precision mask is used to selectively irradiate the organic functional ink in the effective display area with first ultraviolet light (such as 315nm-400nm), so that the organic functional ink is initially cured and formed into an inkjet printed organic functional layer; while the leveling boundary is masked, the wettability of the photoresponse variable wettability functional layer remains unchanged (still hydrophobic).

[0142] S4: Adjust the illumination mode and selectively irradiate the photoresponse variable wettability functional layer with a second ultraviolet light (e.g., 315nm-400nm). By controlling the illumination intensity, time, or scanning path of the second ultraviolet light irradiating the photoresponse variable wettability functional layer on the slope, a wettability gradient is formed on the slope (e.g., from the top of the slope to the bottom, the hydrophilicity gradually increases). This gradient wettability is beneficial for more precise guidance and control of the micro-flow and morphology of the organic functional ink in the AA area before curing in the edge region, so as to achieve the best edge encapsulation effect.

[0143] The edge of the inkjet-printed organic functional layer that has been cured in the AA region comes into contact with the surface of the hydrophilic, photoresponsive, and wettable functional layer, which optimizes the interface energy, helps to release edge stress, and obtains a smooth transition morphology.

[0144] The entire display panel is subjected to final processing using visible light or heat to restore the photoresponse variable wettability functional layer to an inverse hydrophobic state, or to maintain a hydrophilic state according to subsequent process requirements.

[0145] This application achieves the following effects at the leveling boundary (the surface of the inorganic barrier film layer corresponding to the barrier structure) by finely masking and depositing a photoresponsive variable wettability functional layer through IJP partition printing or iCVD process. By controlling the ambient light (visible light and ultraviolet light), the leveling boundary is made hydrophobic during the printing stage to prevent excessive leveling; and hydrophilic during the curing stage to restore the edge morphology. This greatly improves the IJP process margin, achieves high-precision leveling control, and reduces the risk of GDS and Peeling in subsequent process stages.

[0146] The third aspect of this application provides a fabrication system for preparing the display panel described in the first aspect of this application, comprising: a unit for depositing the photoresponse variable wettability functional layer, a specific wavelength light source chamber for regulating wettability, and a photocuring unit capable of selective irradiation by region and wavelength; wherein the light source chamber is capable of outputting 400nm-700nm visible light and 315nm-400nm ultraviolet light.

[0147] This application does not particularly limit the specific equipment used for depositing the photoresponsive variable wettability functional layer, as long as it can achieve the purpose of this application, such as an iCVD chamber; this application does not particularly limit the specific equipment used for the photocuring unit, as long as it can achieve the purpose of this application, such as a DLP device.

[0148] The above description is only a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A display panel, characterized by, include: A substrate includes a substrate and a TFT stack formed on the surface of the substrate; the TFT stack forms a barrier structure including enclosures and / or trenches through the thickness difference of its own film layers; the area enclosed by the barrier structure is an effective display area; An inorganic barrier film layer is conformally covered on the surface of the TFT stack; The surface of the inorganic barrier film layer at the corresponding position of the barrier structure forms a leveling boundary that contacts the organic functional ink. At least one surface of the leveling boundary is provided with a photoresponsive variable wettability functional layer. The photoresponsive variable wettability functional layer is hydrophobic under visible light irradiation and highly hydrophilic under ultraviolet light irradiation. An inkjet-printed organic functional layer is provided within the effective display area.

2. The display panel according to claim 1, characterized in that: The surface of the leveling boundary includes the sloping surface and / or top surface of the inorganic barrier membrane layer at the corresponding position of the enclosure, and / or the inner wall of the inorganic barrier membrane layer at the corresponding position of the trench.

3. The display panel according to claim 1, characterized in that: The raw materials for the photoresponsive variable wettability functional layer include at least one of fluoroazobenzene polymer, spiropyran, and fumonisin anhydride. The fluorinated azobenzene polymer is selected from at least one of 2,6,2',6'-tetrafluoroazobenzene acrylate alkyl copolymers, C4-C8 perfluoroalkylazobenzene methacrylate copolymers with side chains, o-fluoroazobenzene alkyl acrylate homopolymers, and tetrafluorobenzene ring azovinyl copolymers; the number average molecular weight of the fluorinated azobenzene polymer is 3000-50000. The spiropyran is selected from at least one of 6-nitro-1',3',3'-trimethylindoline spirobenzopyran, 8-methoxy-6-nitro-1',3',3'-trimethylindoline spirobenzopyran, and 6-bromo-1',3',3'-trimethylindoline spirobenzopyran; The spermicidal anhydride is selected from at least one of 2,5-dimethylfuranyl spermicidal anhydride, phenylmonofuranyl-substituted spermicidal anhydride, bisthiophene-spermicidal anhydride, 3-phenyleneethyl-2-(4-pyridinylmethylene) spermicidal ester, and trifluoromethylindolyl spermicidal imide.

4. The display panel according to claim 1, characterized in that: The thickness of the photoresponsive variable wettability functional layer is 30nm-10000nm; Preferably, the photoresponsive variable wettability functional layer is prepared by initiation chemical vapor deposition or partition inkjet printing.

5. The display panel according to any one of claims 1-4, characterized in that: The wavelength of the visible light is 400nm-700nm; the wavelength of the ultraviolet light is 315nm-400nm.

6. A method of producing the display panel according to any one of claims 1 to 5, characterized by, Including the following steps: A substrate is provided, the substrate including a substrate and a TFT stack formed on the surface of the substrate; a barrier structure including barriers and / or trenches is formed by the thickness difference of the stacked film layers of the TFT stack itself, the barrier structure enclosing an effective display area; An inorganic barrier film is conformally deposited on the surface of the TFT stack; A hydrophobic, photoresponsive, variable wettability functional layer is formed on at least one surface of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the barrier structure; organic functional ink is printed into the effective display area. The effective display area is selectively irradiated with ultraviolet light to cure the organic functional ink and form an inkjet-printed organic functional layer. The photoresponsive variable wettability functional layer is irradiated with ultraviolet light to transform it into a highly hydrophilic state, so that the edge of the organic functional ink comes into contact with the highly hydrophilic photoresponsive variable wettability functional layer to form a smooth edge morphology.

7. The production method according to claim 6, wherein The specific steps involved in forming a photoresponsive variable wettability functional layer with a hydrophobic state are as follows: A photoresponsive variable wettability functional layer is deposited on at least one surface of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the barrier structure using an initiation chemical vapor deposition process. The photoresponsive variable wettability functional layer is irradiated with visible light to transform it into a hydrophobic state.

8. The preparation method according to claim 6, characterized in that, The specific steps involved in forming a photoresponsive variable wettability functional layer with a hydrophobic state and printing organic functional inks are as follows: Using a partitioned inkjet printing process, organic functional ink is printed into the effective display area, and photoresponsive variable wettability functional ink is sprayed onto at least one surface of the leveling boundary formed by the inorganic barrier film layer at the corresponding position of the barrier structure to form the photoresponsive variable wettability functional layer; the photoresponsive variable wettability functional layer is transformed into a hydrophobic state by irradiation with visible light.

9. The preparation method according to any one of claims 6-8, characterized in that: By adjusting at least one of the following: the intensity, duration, and scanning path of the ultraviolet light irradiating the photoresponse-variable wettability functional layer at the enclosure and / or ditch slope, a wettability gradient is formed in the photoresponse-variable wettability functional layer.

10. A fabrication system for preparing a display panel according to any one of claims 1-5, characterized in that, include: The unit for depositing the photoresponsive variable wettability functional layer, the specific wavelength light source chamber for regulating wettability, and the photocuring unit capable of selective irradiation by region and wavelength. The light source chamber is capable of outputting 400nm-700nm visible light and 315nm-400nm ultraviolet light.

Images