Coating device and preparation method of display module

Abstract

The application provides a coating device and a preparation method of a display module. The coating device comprises a rotating shaft and a coating head. The coating head is arranged at the end of the rotating shaft. The coating head comprises a coating shell, a center support part, a material storage part and a brushing part. The center support part and the material storage part are arranged inside the coating shell. The brushing part is arranged outside the coating shell. The material storage part is arranged around the center support part. The material storage part is used for storing shading material. The coating shell comprises a plurality of through holes. The material storage part is in communication with the brushing part through the plurality of through holes. The brushing part is used for adsorbing the shading material. The coating shell wraps the material storage part. The coating shell comprises a first elastic material. The coating device provided by the application ensures that the shading material can be continuously and stably supplied to the brushing part, ensures the continuity of the coating process, and avoids damaging the module stack during the coating process.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a coating apparatus and a method for preparing a display module. Background Technology

[0002] One of the current trends in mobile phone development is the pursuit of a large screen-to-body ratio and a reduction in bezel width. As a result, placing the front-facing camera in a hole-punch-hole (HIAA) design has gradually become the mainstream design. However, as the bezels of the hole area in flexible OLED modules become narrower, light can be transmitted through the film structure to the hole wall after the screen is turned on, resulting in light leakage. Summary of the Invention

[0003] In view of this, the purpose of this application is to propose a coating device and a method for preparing a display module to eliminate the problems of light leakage from large-viewing-angle openings and light leakage within the openings affecting the imaging quality of the camera.

[0004] To achieve the above objectives, an embodiment of the first aspect of this application provides a coating apparatus for coating a light-shielding material onto the pore walls of an opening in a film structure, the coating apparatus comprising:

[0005] Rotation axis;

[0006] A coating head, wherein the coating head is disposed at the end of the rotating shaft;

[0007] The coating head includes a coating housing, a central support, a material storage section, and a brushing section. The central support and the material storage section are located inside the coating housing, and the brushing section is located outside the coating housing. The material storage section surrounds the central support and is used to store the light-shielding material. The coating housing includes multiple through holes, and the material storage section communicates with the brushing section through these through holes. The brushing section is used to adsorb the light-shielding material. The coating housing encloses the material storage section and includes a first elastic material.

[0008] When the rotating shaft rotates about its own axis, the coating head extending into the opening rotates synchronously with the rotating shaft, and the brush part is used to contact the hole wall to coat the light-shielding material onto the hole wall.

[0009] Optionally, the central support includes an inflation chamber, and the sidewall of the central support near the material storage section includes a second elastic material. When the inflation chamber is inflated, the central support expands outward and compresses the material storage section.

[0010] Optionally, the material storage section includes a sponge filling the space between the central support and the coated housing.

[0011] Optionally, the coating apparatus further includes:

[0012] A feeding device, which is connected to the material storage unit, is used to transport the light-shielding material to the material storage unit.

[0013] Optionally, the coating apparatus further includes:

[0014] An on / off valve is provided between the feeding device and the material storage section.

[0015] Optionally, the coating housing is columnar and coaxially arranged with the rotating shaft; the brushing part includes a velvet layer, which is fixed to the outer peripheral surface of the coating housing.

[0016] Optionally, the fleece layer includes a first portion and a second portion, the second portion being located on the side of the first portion away from the rotation axis; in the direction perpendicular to the central axis of the coated housing, the size of the first portion is larger than the size of the second portion.

[0017] Optionally, the light-shielding material includes ink, which includes one or more of dark-cured organic adhesive or black ink.

[0018] A second aspect of this application provides a method for manufacturing a display module, the method comprising:

[0019] A membrane structure with openings is provided, the membrane structure comprising a support film, a display panel and an adhesive layer stacked sequentially;

[0020] The light-shielding material is coated onto the wall of the opening using any of the above-described coating apparatuses; wherein, the coating head is inserted into the opening for alignment; air is injected into the central support portion to make the brush portion contact the wall of the opening; the coating head is rotated by a rotating shaft to make the light-shielding material overflow through the through hole to the brush portion and coat the wall of the opening;

[0021] The cover plate is attached to the adhesive layer on the side away from the support film.

[0022] Optionally, after coating the light-shielding material onto the wall of the opening, the method includes:

[0023] Open the valve to replenish ink to the material storage section via the feeding device.

[0024] The coating apparatus provided in this application can solve the problems of light leakage at large viewing angles and light leakage inside the holes by coating the light-shielding material onto the walls of the openings in the film structure. The material storage section and the coating section are connected by a through hole, and the coating shell has a certain degree of elasticity, which ensures that the light-shielding material can be continuously and stably supplied to the coating section, ensuring the continuity of the coating process and avoiding damage to the module stack during the coating process.

[0025] Furthermore, the inflatable central support can be adapted to different apertures, avoiding the hassle of changing coating heads. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the structure of a related display module;

[0028] Figure 2 This is a schematic diagram of the structure of a coating apparatus provided in an embodiment of this application;

[0029] Figure 3 This is a schematic diagram of the structure of a coating device provided in an embodiment of this application when the central support expands;

[0030] Figure 4 This is a schematic diagram of another coating apparatus provided in an embodiment of this application;

[0031] Figure 5 This is a schematic diagram of the structure of a coating device applied in the manufacturing process of a display module, as provided in an embodiment of this application.

[0032] Figure 6 This is a schematic diagram illustrating the structure of another coating apparatus provided in the embodiments of this application, applied in the manufacturing process of a display module.

[0033] Figure 7 This is a schematic diagram of the structure of a display module coated using the coating apparatus provided in the embodiments of this application;

[0034] Figure 8 This is a schematic flowchart illustrating a method for manufacturing a display module according to an embodiment of this application.

[0035] Marker explanation:

[0036] 100. Coating device; 1. Rotating shaft; 2. Coating head; 21. Coating housing; 211. Through hole; 22. Central support; 220. Inflation chamber; 23. Material storage section; 24. Coating section; 240. Fleece layer; 241. First part; 242. Second part; 3. Feeding device; 4. Opening and closing valve; 5. Display module; 501. Opening; 50. Display panel; 51. Support film; 52. Polarizing film; 53. Adhesive layer; 54. Cover plate; 6. Camera. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0038] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0039] In the accompanying drawings, the dimensions of layers and regions may be exaggerated for clarity. It is understood that when a structure is referred to as being "on" or "below" another structure, the structure may be directly on or below the other structure, or there may be intermediate structures. The same reference numerals always indicate the same structure. Structures referred to herein include any of the following: membrane, element, device, component, assembly.

[0040] When a structure is referred to as being “connected” to another structure, it can be directly connected to the other structure or indirectly connected to the other structure by means of one or more intermediate structures placed between them.

[0041] As smartphones move towards higher screen-to-body ratios, the bezel width of the camera hole area (HIAA area) is gradually decreasing.

[0042] Figure 1 This is a structural schematic diagram of a related display module. For example... Figure 1As shown, in the related technology, the display module 5 includes a film layer structure with an opening 501. The film layer structure includes a support film 51, a display panel 50, a polarizer 52, an adhesive layer 53, and a cover plate 54, which are sequentially stacked on a composite tape. During assembly, the camera of the camera module extends into the opening 501.

[0043] However, the inventors of this application discovered that the area where the aperture 501 is located is prone to the following light leakage problems: large-viewing-angle light leakage, where a ring of light is visible on the aperture wall when the viewing angle is greater than 45°, severely affecting the visual effect; and internal light leakage, where light leaks into the interior of the aperture 501, interfering with the camera's image quality. The main cause of light leakage is that after the screen is lit, light is transmitted laterally through the module stack to the aperture wall. Traditional processes, due to insufficient ink coating precision and excessive rigidity of the coating device, cannot effectively block light and are prone to damaging the module stack. Therefore, a solution is urgently needed that can accurately coat the ink, adapt to different aperture diameters, and avoid damaging the module.

[0044] Therefore, this application provides a coating apparatus to solve the above-mentioned problems.

[0045] Figure 2 This is a schematic diagram of a coating apparatus provided in an embodiment of this application. Figure 2 As shown, an embodiment of the first aspect of this application provides a coating apparatus 100 for coating a light-shielding material onto the wall of an opening 501 in a film structure. The light-shielding material may specifically be ink. The coating apparatus 100 includes a rotating shaft 1 and a coating head 2, the coating head 2 being disposed at the end of the rotating shaft 1.

[0046] The coating head 2 includes a coating housing 21, a central support 22, a material storage section 23, and a brushing section 24. The central support 22 and the material storage section 23 are disposed inside the coating housing 21, and the brushing section 24 is disposed outside the coating housing 21. The material storage section 23 is arranged around the central support 22 and is used to store light-shielding material. The coating housing 21 includes multiple through holes 211, through which the material storage section 23 communicates with the brushing section 24, and the brushing section 24 is used to adsorb the light-shielding material. The coating housing 21 encloses the material storage section 23, and the coating housing 21 includes a first elastic material.

[0047] When the rotating shaft 1 rotates around its own axis, the coating head 2 extending into the opening 501 rotates synchronously with the rotating shaft 1, and the brush part 24 is used to contact the hole wall to coat the light-shielding material onto the hole wall.

[0048] Specifically, the rotating shaft 1 of the coating apparatus 100 can be connected to a drive motor, which provides stable rotational power to the rotating shaft 1. The central support portion 22 and the material storage portion 23 of the coating head 2 are located inside the coating housing 21. Optionally, the material storage portion 23 is evenly distributed around the central support portion 22 to ensure the uniformity of storage and delivery of the light-shielding material. The brushing portion 24 is fixed to the outside of the coating housing 21. Specifically, a soft velvet cloth (such as polyester fiber velvet cloth) with good ink absorption capacity can be covered around the coating housing 21 to form the brushing portion 24. The coating housing 21 is also made of a soft elastic material, such as silicone, to avoid scratching or extrusion deformation of the film structure. The coating housing 21 is manufactured with a specific shape and size by means of a mold to ensure that its strength and elasticity meet the usage requirements. The coating housing 21 tightly covers the material storage portion 23, which helps the light-shielding material to flow out smoothly and evenly from the through holes 211 on the coating housing 21, thereby improving the coating effect.

[0049] During the coating operation, the coating device 100 is moved above the opening 501 of the film structure, and the coating head 2 is aligned with the opening 501 and slowly inserted. The rotating shaft 1 is started, causing the coating head 2 to rotate synchronously. At this time, the light-shielding material in the material storage section 23 permeates through the through-hole 211 into the brushing section 24. The brushing section 24 contacts the wall of the opening 501, and during rotation, the light-shielding material is evenly coated onto the wall of the opening. During the coating operation, when the coating head 2 is inserted into the opening 501 and subjected to external pressure, the coating housing 21 can deform to a certain extent due to its elasticity, thereby better adapting to changes in the shape and size of the opening. During the rotational coating process, the elasticity of the coating housing 21 can also buffer the friction between the brushing section 24 and the wall of the opening, preventing damage to the wall of the opening or the brushing section 24 due to excessive friction.

[0050] For example, the coating head 2 is rotated at a uniform speed (adjustable from 30-100 rpm) by rotating shaft 1, ensuring that the ink evenly covers the hole walls and avoiding light leakage caused by localized lack of coverage. Experimental data shows that this design reduces light leakage by more than 90%.

[0051] The coating apparatus 100 in this embodiment achieves automated rotary coating by setting a rotating shaft 1 and a coating head 2 with a special structure, improving coating efficiency and uniformity. The material storage unit 23 and the brushing unit 24 are connected through a through hole 211, and the coating housing 21 has a certain degree of elasticity, ensuring that the light-shielding material can be continuously and stably supplied to the brushing unit 24, ensuring the continuity of the coating process, effectively eliminating coating defects caused by insufficient material supply, thereby improving the light-shielding performance of the product, reducing light leakage, and improving product quality. In addition, the elastic coating housing 21 can also reduce damage to the film structure and the coating apparatus itself caused by collisions or friction, extending the service life of the coating apparatus, effectively improving the product yield and the reliability of the production equipment. Finally, only one coating process needs to be added to the existing module manufacturing process, without changing the OLED array manufacturing process, resulting in low implementation cost and high efficiency.

[0052] Figure 3 This is a schematic diagram of the structure of a coating device provided in an embodiment of this application when the central support expands. Figure 3 As shown, the central support 22 includes an inflation chamber 220, and the side wall of the central support 22 near the material storage section 23 includes a second elastic material; when the inflation chamber 220 is inflated, the central support 22 expands outward and squeezes the material storage section 23.

[0053] Optionally, the material storage section 23 includes a sponge filling the space between the central support section 22 and the coated housing 21.

[0054] Specifically, the central support 22 is made of a suitable elastic material, such as rubber, and is formed during manufacturing through injection molding or compression molding to ensure good sealing of the internal air chamber 220. The material storage section 23 is made of sponge, which is cut into suitable shapes and sizes and tightly wrapped around the central support 22 and in contact with the coating housing 21. Before coating, the coating head 2 is inserted into the opening 501 and then connected to the inflation port of the central support 22 through an inflation device to inflate the air chamber 220. The inflation port of the central support 22 can be located inside the rotating shaft 1. As gas is injected, the central support 22 gradually expands outward. Due to the good elasticity and compressibility of the sponge, the light-blocking material stored inside the sponge is squeezed out by the central support 22 and flows to the coating section 24 through the through hole 211. During the coating process, the inflation volume can be adjusted according to the size of the opening 501 and the coating requirements to control the expansion degree of the central support 22, thereby adjusting the amount of light-shielding material extruded by the material storage section 23 and the contact pressure between the brushing section 24 and the hole wall. The combination of the elasticity of the sponge and the pressure resistance of the rubber extends the life of the device and adapts to high-frequency inflation and deflation operations.

[0055] The central support section 22 features an inflatable expansion design, allowing it to flexibly adapt to openings of different diameters. In actual production, the opening sizes of products may vary, and traditional rigid coating heads struggle to meet the coating requirements of different pore sizes. By adjusting the diameter of the central support section 22 through inflation, the coating head 2 can better fit openings of different diameters, improving the versatility of the coating device. Simultaneously, the expansion and compression of the sponge material storage section 23 by the central support section 22 enables automatic extrusion and supply of the light-shielding material, eliminating the need for additional complex feeding equipment and simplifying the structure of the coating device. This design also allows for precise control of the amount of light-shielding material coated, avoiding quality problems caused by material waste or insufficient coating, improving production efficiency and product quality, and effectively solving the coating challenges of openings with different diameters, as well as material supply and control issues. Furthermore, in the material storage section 23, the high ink absorption of the sponge ensures stable ink storage, and the inflation and compression method allows for on-demand ink release, avoiding over- or under-filling.

[0056] Therefore, the central support 22 of the coating head 2 is elastic, which allows the coating head 2 to better adapt to openings of different sizes. Combined with the elasticity of the coating housing 21, it avoids damage to the film structure during the coating process, thus solving the problems of coating difficulties and film damage caused by differences in opening size. It is especially suitable for ultra-narrow bezel modules.

[0057] Figure 4 This is a schematic diagram of another coating apparatus provided in an embodiment of this application.

[0058] like Figure 4 As shown, in another embodiment, the coating apparatus 100 further includes a feeding device 3, which is connected to the material storage unit 23 and is used to transport the light-shielding material to the material storage unit 23.

[0059] Furthermore, the coating apparatus 100 also includes an on / off valve 4, which is disposed between the feeding device 3 and the material storage section 23.

[0060] For example, the feeding device 3 may include a storage tank, a conveying pipe, and a conveying pump. The storage tank is used to store a large amount of light-shielding material. The conveying pipe connects the storage tank and the material storage section 23, and the conveying pump is installed on the conveying pipe to provide power for conveying the light-shielding material. During installation, ensure that the conveying pipe is tightly connected to prevent leakage of the light-shielding material. Before the coating operation, the light-shielding material is loaded into the storage tank, and the conveying pump is started. The light-shielding material flows into the material storage section 23 through the conveying pipe under the action of the conveying pump. During the coating process, the flow rate and conveying time of the conveying pump can be adjusted according to the material consumption of the material storage section 23 to ensure that the material storage section 23 always has a sufficient supply of light-shielding material. The on / off valve 4 is installed on the conveying pipe between the feeding device 3 and the material storage section 23. During installation, ensure that its installation position is convenient for operation and maintenance. Before the coating operation, close the on / off valve 4 to prevent the light-shielding material from flowing into the material storage section 23 before coating, which would cause material waste or contamination. During the coating process, when the light-shielding material in the material storage unit 23 is about to run out, the on / off valve 4 is opened, the feeding device 3 is started, and the light-shielding material begins to be fed into the material storage unit 23. When the material storage unit 23 is replenished with sufficient light-shielding material, the on / off valve 4 is closed, and the feeding stops. By controlling the opening and closing time of the on / off valve 4, the amount of material replenished to the material storage unit 23 can be precisely controlled.

[0061] The addition of the feeding device 3 solves the problem of continuous supply of light-shielding material to the material storage section 23. During long coating operations, relying solely on the initial storage capacity of the material storage section 23 is insufficient to meet the coating needs of a large number of products, easily leading to material shortages, coating interruptions, and reduced production efficiency. The feeding device 3 ensures a continuous supply of light-shielding material, guaranteeing the continuity of the coating operation and significantly improving production efficiency. Furthermore, by controlling the feeding device 3, the amount of light-shielding material delivered to the material storage section 23 can be precisely adjusted, avoiding material waste and reducing production costs. The on / off valve 4 further optimizes the supply control of the light-shielding material. The on / off valve 4 automatically activates to replenish ink after each coating cycle, preventing ink waste and preventing ink from drying out when not in use. Without the on / off valve 4, the feeding device 3 might continuously supply material to the material storage section 23, resulting in excessive light-shielding material, which not only wastes material but may also affect the coating effect. The on / off valve 4 can precisely control the timing and amount of material replenishment according to actual needs, avoiding oversupply and waste. At the same time, it can also cut off the material supply channel when coating operations are not being performed, preventing the leakage and contamination of the light-shielding material, thus ensuring the cleanliness of the production environment and the normal operation of the coating equipment.

[0062] In one embodiment, the coating housing 21 is columnar and coaxially arranged with the rotation shaft 1. That is, the central axis of the coating housing 21 coincides with the central axis of the rotation shaft 1. The brushing part 24 includes a fleece layer 240, which is fixed to the outer peripheral surface of the coating housing 21.

[0063] For example, the coating housing 21 can be a cylinder. When manufacturing the coating housing 21, it is made into a cylindrical shape through machining or injection molding, ensuring that its central axis precisely coincides with the central axis of the rotating shaft 1 to guarantee the stability and uniformity of the coating process. The fleece layer 240 is made of soft fleece with good ink absorption capacity. The fleece is cut to a suitable size and tightly fixed to the outer circumference of the coating housing 21 using glue or other fixing methods. During the coating operation, the coating head 2 rotates with the rotating shaft 1, and the fleece layer 240 contacts the hole wall of the opening 501. Due to the fleece's good ink absorption properties, the light-shielding material overflowing from the through hole 211 is absorbed by the fleece and evenly coated onto the hole wall during rotation.

[0064] The columnar design of the coating housing 21, coinciding with the central axis of the rotating shaft 1, ensures uniform force distribution on the coating head 2 during rotation, guaranteeing the uniformity of the light-shielding material coating. Traditional coating heads, if poorly designed, are prone to eccentricity during rotational coating, resulting in inconsistent coating thickness of the light-shielding material on the orifice walls and affecting the light-shielding effect. The coaxial design ensures no eccentric wobbling during the rotation of the coating head 2, improving coating uniformity and enhancing product quality. The felt layer 240, a key component of the brushing section 24, possesses excellent ink absorption capacity, ensuring the light-shielding material is fully adsorbed onto the felt and evenly transferred to the orifice walls. The microporous structure of the felt absorbs ink and releases it evenly, preventing ink dripping and contamination of the module. Simultaneously, the soft felt layer does not damage the orifice walls, solving the problems of uneven coating and orifice wall damage, thus improving product yield and reliability.

[0065] Figure 6 This is a schematic diagram illustrating the structure of another coating apparatus provided in this application, applied in the fabrication process of a display module. (See attached diagram.) Figure 6 As shown, the fleece layer 240 includes a first portion 241 and a second portion 242, with the second portion 242 located on the side of the first portion 241 away from the rotation axis 1. In the direction perpendicular to the central axis of the coated housing 21, the size of the first portion 241 is larger than the size of the second portion 242.

[0066] The fleece layer 240 is divided into two parts. The second part 242 is shorter and located at the far end of the rotation axis 1, making it particularly suitable for the hole walls of the upper film layer with an inward-shrinking design. For example, when cutting the fleece to make the fleece layer 240, the fleece is cut into a first part 241 and a second part 242 according to design requirements, with the second part 242 located on the side of the first part 241 away from the rotation axis 1. It is also ensured that, in the direction perpendicular to the central axis of the coating housing 21, the size of the first part 241 is larger than the size of the second part 242. When fixing the cut fleece layer 240 to the outer circumference of the coating housing 21, the fleece is kept flat and firmly fixed to ensure uniform coating of all parts of the hole walls.

[0067] Specifically, the film structure includes a support film 51, a display panel 50, and an adhesive layer 53 stacked sequentially. The adhesive layer 53 is used to attach a cover plate 54. If the adhesive layer 53 is applied to the display panel 50 and aligned with the edge of the opening 501 in the display panel 50, the adhesive layer 53 will deform when the cover plate 54 and the adhesive layer 53 are attached, thus squeezing the adhesive layer 53 into the opening 501 and causing adhesive overflow. Therefore, when applying the adhesive layer 53 to the display panel 50, the adhesive layer 53 is spaced a distance from the edge of the opening 501 to avoid adhesive overflow. Therefore, in order to ensure that the hole walls at the inwardly recessed adhesive layer 53 are also completely coated with the light-shielding coating, the size of the side of the velvet layer 240 near the rotation axis 1 can be set to be larger than the size of the side of the velvet layer 240 away from the rotation axis 1. The longer velvet of the first part 241 is used to coat the sidewalls of the adhesive layer 53, and the shorter velvet of the second part 242 is used to coat the sidewalls of the display panel 50 and the support film 51.

[0068] It is worth noting that the difference between the size of the first part 241 and the size of the second part 242 can be set by the distance of the inward retraction of the edge of the adhesive layer 53, and no specific limitation is made in this embodiment.

[0069] Furthermore, during the actual coating process, the coating requirements may differ for different parts of the aperture wall. The larger size of the felt in the first part 241 meets the needs of that part. The felt in the second part 242 then applies additional coating to other parts of the aperture wall, ensuring that the entire aperture wall is evenly coated with the light-shielding material, thus avoiding light leakage caused by uneven coating. Simultaneously, this design can adapt to apertures of different shapes and sizes, improving the versatility of the coating device and effectively solving the problems of uneven coating and poor adaptability to different apertures, thereby enhancing the light-shielding performance and applicability of the product.

[0070] Optionally, the axial height of the coating head 2 is greater than or equal to the height of the opening 501 in the film structure. In this way, the driving mechanism can rotate the coating head 2 around the central axis once to achieve coating of the opening wall of the opening 501 without the need for multiple coats.

[0071] In some embodiments, the light-shielding material includes ink, which includes one or more of dark-cured organic adhesive or black ink.

[0072] For example, when selecting a light-shielding material, one or more can be selected from dark-colored curable organic adhesives or black ink and mixed according to actual needs. During the coating process, the light-shielding material is conveyed to the material storage section 23 through the feeding device 3, then penetrates into the coating section 24 through the through-hole 211, and is finally coated on the wall of the opening 501. After coating, a corresponding curing treatment is performed according to the type of light-shielding material selected. For example, for dark-colored curable organic adhesives that require light curing, a light source of a specific wavelength is used for irradiation and curing. Dark-colored UV-curable adhesives or black inks are preferred as light-shielding materials. UV adhesives form a dense film layer after curing with a light-shielding rate of ≥99%; black inks are low in cost and suitable for rapid curing processes.

[0073] Among them, the light-blocking material has a high light-blocking rate, effectively blocking light from passing through the opening walls, reducing light leakage, and improving the product's visual effect. The dark-colored curing organic adhesive has good stability and durability after curing, ensuring the long-term reliability of the light-blocking effect. The black ink has good flowability and adhesion, facilitating the coating process. The light-blocking material improves the light-blocking effect while ensuring the operability of the coating process and the long-term stability of the product.

[0074] Figure 7 This is a schematic diagram of the structure of a display module coated using the coating apparatus provided in the embodiments of this application. Figure 8 This is a schematic flowchart illustrating a method for fabricating a display module according to an embodiment of this application. Figure 7 , Figure 8 As shown, an embodiment of the second aspect of this application also provides a method for preparing a display module.

[0075] The manufacturing method of display module 5 includes:

[0076] Step S1: Provide a film structure with openings 501. The film structure includes a support film 51, a display panel 50, and an adhesive layer 53 stacked sequentially.

[0077] Specifically, the aperture 501 penetrates the film layer structure, which may include a support film, a display panel, and an adhesive layer stacked sequentially. The aperture penetrates the adhesive layer, the display panel, and the support film. In some embodiments, a polarizer is also disposed between the display panel and the adhesive layer; in this case, the aperture also penetrates the polarizer.

[0078] Step S2: Using the coating apparatus 100 in the first aspect embodiment, a light-shielding material is coated onto the wall of the opening 501; wherein, the coating head 2 is inserted into the opening 501; air is injected into the center support 22 of the center support 22 so that the brushing part 24 contacts the wall of the opening; the coating head 2 is rotated by the rotating shaft 1 so that the light-shielding material overflows through the through hole 211 to the brushing part 24 and coats the wall of the opening.

[0079] Specifically, openings are typically used to house light-collecting devices. Since light leakage from the opening walls can affect the performance of these devices, a coating device is used to apply a light-shielding material to the inner walls of the openings to prevent light leakage. This can be done manually or electrically by moving a rotating shaft, which in turn moves a coating head connected to the shaft into the opening of the film structure. This allows the light-shielding material adhering to the coating head's surface to be applied to the inner walls of the openings, thus solving the light leakage problem. Compared to fabricating a light-shielding film layer on the opening walls, this method is simpler and less expensive.

[0080] Step S3: Attach the cover plate 54 to the side of the adhesive layer 53 away from the support film 51.

[0081] After applying a light-shielding material to the wall of the opening using the coating apparatus of the first aspect embodiment, the cover plate 54 is attached to the side of the adhesive layer 53 away from the support film 51. The side of the cover plate 54 closest to the adhesive layer 53 has a light-shielding layer.

[0082] When preparing the display module 5, a film structure with openings 501 is first prepared, ensuring that the support film 51, display panel 50, polarizer 52, and adhesive layer 53 are stacked sequentially and tightly bonded. Specifically, after the adhesive layer 53 is bonded and before the cover plate 54 is bonded, the semi-finished display module is placed on the perforated platform; the coating head 2 is aligned with the minimum diameter and enters the opening 501, inflated to the working size, ensuring contact with the hole wall; the rotating shaft 1 is started, and the rotating shaft 1 drives the coating head 2 to rotate. During the rotation, the light-shielding material in the material storage section 23 overflows through the through hole 211 to the coating section 24 and is evenly coated on the hole wall; after coating is completed, the opening and closing valve is opened to replenish ink, preparing for the next cycle. The cover plate 54 is then bonded to the side of the adhesive layer 53 away from the support film 51.

[0083] In the traditional display module manufacturing process, the lack of effective light-shielding treatment on the walls of the openings leads to severe light leakage, affecting display performance and camera image quality. By using a coating device 100 to coat the walls of the openings in the film structure with a light-shielding material, light is effectively blocked, reducing the impact of large-viewing-angle light leakage and intra-hole light leakage on camera image quality. This application adds a simple coating process without changing other processes in the display module manufacturing, resulting in low cost and high feasibility. Furthermore, by precisely controlling various parameters during the coating process, such as air volume and rotation speed, coating quality is ensured.

[0084] Specifically, in the embodiments of this application, the central support portion 22 can be made of an elastic material, such as rubber, and the material storage portion 23 is made of sponge, tightly surrounding the central support portion 22 and contacting the coating housing 21. Before coating, the coating head 2 is inserted into the opening 501, and then connected to the inflation port of the central support portion 22 via an inflation device to inflate the inflation chamber 220. The inflation port of the central support portion 22 can be located inside the rotating shaft 1. As gas is injected, the central support portion 22 gradually expands outward. Due to the good elasticity and compressibility of the sponge, the light-shielding material stored inside the sponge is squeezed out under the pressure of the central support portion 22 and flows to the brushing portion 24 through the through hole 211. During the coating process, the inflation amount can be adjusted according to the size of the opening 501 and the coating requirements to control the degree of expansion of the central support portion 22, thereby adjusting the amount of light-shielding material squeezed out by the material storage portion 23 and the contact pressure between the brushing portion 24 and the hole wall. The combination of the elasticity of the sponge and the pressure resistance of the rubber extends the life of the device and allows it to adapt to high-frequency inflation and deflation operations.

[0085] The central support section 22 features an inflatable expansion design, allowing it to flexibly adapt to openings of different diameters. In actual production, the opening sizes of products may vary, and traditional rigid coating heads struggle to meet the coating requirements of different pore sizes. By adjusting the diameter of the central support section 22 through inflation, the coating head 2 can better fit openings of different diameters, improving the versatility of the coating device. Simultaneously, the expansion and compression of the sponge material storage section 23 by the central support section 22 enables automatic extrusion and supply of the light-shielding material, eliminating the need for additional complex feeding equipment and simplifying the structure of the coating device. This design also allows for precise control of the amount of light-shielding material coated, avoiding quality problems caused by material waste or insufficient coating, improving production efficiency and product quality, and effectively solving the coating challenges of openings with different diameters, as well as material supply and control issues. Furthermore, in the material storage section 23, the high ink absorption of the sponge ensures stable ink storage, and the inflation and compression method allows for on-demand ink release, avoiding over- or under-filling.

[0086] Therefore, the central support portion 22 of the coating head 2 is elastic, which allows the coating head 2 to better adapt to openings of different sizes. Combined with the elasticity of the coating housing 21, it avoids damage to the film structure during the coating process, thus solving the problems of coating difficulties and film damage caused by differences in opening size.

[0087] In some embodiments, after applying a light-shielding material to the inner wall of the opening using the coating apparatus of the first aspect embodiment, a composite tape is also attached to the side of the support film away from the cover plate.

[0088] Further, in step S2, after applying a light-shielding material to the wall of the opening 501 using the coating apparatus 100 as described in the first aspect embodiment, the method for preparing the display module 5 includes:

[0089] Open the on / off valve 4 and replenish ink to the material storage section 23 through the feeding device 3.

[0090] For example, the feeding device 3 may include a storage tank, a conveying pipe, and a conveying pump. The storage tank is used to store a large amount of light-shielding material. The conveying pipe connects the storage tank and the material storage section 23, and the conveying pump is installed on the conveying pipe to provide power for conveying the light-shielding material. During installation, ensure that the conveying pipe is tightly connected to prevent leakage of the light-shielding material. Before the coating operation, the light-shielding material is loaded into the storage tank, and the conveying pump is started. The light-shielding material flows into the material storage section 23 through the conveying pipe under the action of the conveying pump. During the coating process, the flow rate and conveying time of the conveying pump can be adjusted according to the material consumption of the material storage section 23 to ensure that the material storage section 23 always has a sufficient supply of light-shielding material. The on / off valve 4 is installed on the conveying pipe between the feeding device 3 and the material storage section 23. During installation, ensure that its installation position is convenient for operation and maintenance. Before the coating operation, close the on / off valve 4 to prevent the light-shielding material from flowing into the material storage section 23 before coating, which would cause material waste or contamination. During the coating process, when the light-shielding material in the material storage unit 23 is about to run out, the on / off valve 4 is opened, the feeding device 3 is started, and the light-shielding material begins to be fed into the material storage unit 23. When the material storage unit 23 is replenished with sufficient light-shielding material, the on / off valve 4 is closed, and the feeding stops. By controlling the opening and closing time of the on / off valve 4, the amount of material replenished to the material storage unit 23 can be precisely controlled.

[0091] The addition of the feeding device 3 solves the problem of continuous supply of light-shielding material to the material storage section 23. During long coating operations, relying solely on the initial storage capacity of the material storage section 23 is insufficient to meet the coating needs of a large number of products, easily leading to material shortages, coating interruptions, and reduced production efficiency. The feeding device 3 ensures a continuous supply of light-shielding material, guaranteeing the continuity of the coating operation and significantly improving production efficiency. Furthermore, by controlling the feeding device 3, the amount of light-shielding material delivered to the material storage section 23 can be precisely adjusted, avoiding material waste and reducing production costs. The on / off valve 4 further optimizes the supply control of the light-shielding material. The on / off valve 4 automatically activates to replenish ink after each coating cycle, preventing ink waste and preventing ink from drying out when not in use. Without the on / off valve 4, the feeding device 3 might continuously supply material to the material storage section 23, resulting in excessive light-shielding material, which not only wastes material but may also affect the coating effect. The on / off valve 4 can precisely control the timing and amount of material replenishment according to actual needs, avoiding oversupply and waste. At the same time, it can also cut off the material supply channel when coating operations are not being performed, preventing the leakage and contamination of the light-shielding material, thus ensuring the cleanliness of the production environment and the normal operation of the coating equipment.

[0092] The steps of the various methods described above are only for clarity. In practice, they can be combined into one step or some steps can be split into multiple steps. As long as they include the same logical relationship, they are all within the scope of protection of this patent. Adding insignificant modifications or introducing insignificant designs to the algorithm or process, but without changing the core design of the algorithm and process, are also within the scope of protection of this patent.

[0093] It is not difficult to see that this embodiment is a method implementation using the apparatus of the first aspect embodiment. The relevant technical details mentioned in the first aspect embodiment are still valid in this embodiment, and will not be repeated here to avoid repetition.

[0094] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description.

[0095] It should be noted that the above description describes some embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in a different order than that shown in the above embodiments and still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0096] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A coating apparatus, characterized in that, The coating apparatus is used to coat the walls of the openings in a film structure with a light-shielding material, the coating apparatus comprising: Rotation axis; A coating head, wherein the coating head is disposed at the end of the rotating shaft; The coating head includes a coating housing, a central support, a material storage section, and a brushing section. The central support and the material storage section are located inside the coating housing, and the brushing section is located outside the coating housing. The material storage section surrounds the central support and is used to store the light-shielding material. The coating housing includes multiple through holes, and the material storage section communicates with the brushing section through these through holes. The brushing section is used to adsorb the light-shielding material. The coating housing encloses the material storage section and includes a first elastic material. When the rotating shaft rotates about its own axis, the coating head extending into the opening rotates synchronously with the rotating shaft, and the brush part is used to contact the hole wall to coat the light-shielding material onto the hole wall.

2. The coating apparatus according to claim 1, characterized in that, The central support includes an air chamber, and the side wall of the central support near the material storage section includes a second elastic material. When air is inflated into the air chamber, the central support expands outward and compresses the material storage section.

3. The coating apparatus according to claim 1, characterized in that, The material storage section includes a sponge filling the space between the central support section and the coated housing.

4. The coating apparatus according to claim 1, characterized in that, The coating apparatus further includes: A feeding device, which is connected to the material storage unit, is used to transport the light-shielding material to the material storage unit.

5. The coating apparatus according to claim 4, characterized in that, The coating apparatus further includes: An on / off valve is provided between the feeding device and the material storage section.

6. The coating apparatus according to claim 1, characterized in that, The coating housing is columnar and is coaxially arranged with the rotating shaft; the brushing part includes a velvet layer, which is fixed to the outer peripheral surface of the coating housing.

7. The coating apparatus according to claim 6, characterized in that, The fleece layer includes a first part and a second part, the second part being located on the side of the first part away from the rotation axis; in the direction perpendicular to the central axis of the coated housing, the size of the first part is larger than the size of the second part.

8. The coating apparatus according to claim 1, characterized in that, The light-shielding material includes ink, which includes one or more of dark-cured organic adhesive or black ink.

9. A method for manufacturing a display module, characterized in that, The method includes: A membrane structure with openings is provided, the membrane structure comprising a support film, a display panel and an adhesive layer stacked sequentially; Using the coating apparatus as described in any one of claims 1 to 8, the light-shielding material is coated onto the wall of the opening; wherein, the coating head is inserted into the opening for alignment; air is injected into the central support portion to make the brush portion contact the wall of the opening; the coating head is rotated by a rotating shaft to make the light-shielding material overflow through the through hole to the brush portion and coat the wall of the opening; The cover plate is attached to the adhesive layer on the side away from the support film.

10. The method for preparing a display module according to claim 9, characterized in that, After coating the light-shielding material onto the wall of the opening, the method includes: Open the valve to replenish ink to the material storage section via the feeding device.

Images