Printing device and forming method of a line protection layer of a display device

Abstract

The present application relates to the technical field of 3D printing, and particularly relates to a printing device and forming method of a circuit protection layer of a display device. The printing device of the present application comprises: a main support; the main support has a front end and a rear end along a horizontal direction; at least two barrier wall printing units, which are adapted to print and form barrier walls on the surface of the connection area and / or non-connection area of a flexible circuit board respectively; the printing unit comprises a printing needle; the printing units are arranged at intervals in the direction from the front end to the rear end; a filling glue printing unit is arranged at intervals with the barrier wall printing units in the direction from the front end to the rear end, is located between the rear end and the barrier wall printing units, and is adapted to print filling glue in the space between the multiple barrier walls formed by the multiple printing units to form a circuit protection layer; the circuit protection layer covers at least the connection area. The present application can effectively solve the problems of poor uniformity of the film layer thickness of the circuit protection layer, influence on packaging, and even possible influence on the display effect.

Description

Technical Field

[0001] This invention relates to the field of 3D printing technology, and more specifically to an apparatus and method for printing a circuit protection layer for a display device. Background Technology

[0002] In recent years, "high screen-to-body ratio" and even "full-screen" designs have gradually become the mainstream design for electronic products such as mobile phones, tablets, laptops, and televisions. One of the most effective ways to increase the screen-to-body ratio is to hide the screen driver IC in the side or back of the OLED screen by bending it with a flexible circuit board. However, how to effectively protect the fragile metal traces during the bending process has become one of the most important aspects.

[0003] Typically, a Metal Cover Layer (MCL) is formed on the connection area between the flexible circuit board and the display panel before bending. This protects the metal traces in the connection area, enhances the resistance and durability of the flexible board, and reduces the risk of bright lines and other risks caused by damage to the metal traces in the connection area during bending and subsequent product use.

[0004] However, the protective layer formed by existing technology will show a depression on the side near the display panel, followed by a sharp slope, and may overflow onto the upper surface of the display panel, affecting subsequent packaging and even the display effect; in addition, the film thickness of the protective layer is not uniform, so when the flexible circuit board and the display panel are folded, the actual size of the part at the bottom of the display device is much different from the design size, and the poor uniformity will also affect the accuracy of subsequent assembly processes. Summary of the Invention

[0005] Therefore, in order to solve the problem of poor uniformity of the thickness of the circuit protection layer, which affects the packaging and may even affect the display effect, the present invention provides a printing apparatus and a forming method for the circuit protection layer of a display device.

[0006] This invention provides a printing apparatus for a circuit protection layer of a display device. The display device includes a display panel and a flexible circuit board on the side of the display panel. The flexible circuit board has a connection area connected to the display panel and a non-connection area connected to the connection area. The printing apparatus includes: a main support; the main support has a front end and a rear end in a horizontal direction; at least two barrier printing units adapted to print barriers on the surfaces of the connection area and / or the non-connection area, respectively; each printing unit includes a printing needle; the printing units are spaced apart in the direction from the front end to the rear end of the main support; and a filler adhesive printing unit, spaced apart from the barrier printing units in the direction from the front end to the rear end of the main support, located between the rear end and the barrier printing units, adapted to print filler adhesive in the space between the multiple barriers formed by the multiple printing units to form the circuit protection layer; the circuit protection layer at least covers the connection area.

[0007] Optionally, the retaining wall printing unit is provided with a clamp for holding the printing needle.

[0008] Optionally, the retaining wall printing unit is provided with a needle-falling motion axis, which is parallel to the surface of the main support connecting the retaining wall printing unit and perpendicular to the horizontal direction; the clamp is adapted to move along the needle-falling motion axis.

[0009] Optionally, the printing needles of adjacent retaining wall printing units are spaced apart by a first gap in a horizontal direction parallel to the surface of the main support connecting the retaining wall printing unit, and the first gap is adjustable.

[0010] Optionally, at least one of the adjacent retaining wall printing units is provided with a spacing adjustment shaft, which is arranged horizontally parallel to the surface of the main support connecting the retaining wall printing unit and is movably connected to the clamp; the clamp is adapted to move horizontally along the spacing adjustment shaft to adjust the first spacing.

[0011] Optionally, the retaining wall printing unit is further provided with a retaining wall curing component, which is spaced apart from the printing needle and connected to the clamp.

[0012] Optionally, there is a second spacing between the printing needles of adjacent printing units in a horizontal direction perpendicular to the surface of the main support connecting the barrier printing unit, and the second spacing is greater than the diameter of the printing needle.

[0013] Optionally, the main support frame further includes, along the direction from the front end to the rear end: a scanning unit, disposed near the front end; the scanning unit is used to scan the display device to measure the required dimensions; a pre-processing unit, disposed between the scanning unit and the barrier printing unit; the pre-processing unit includes at least one of: a solvent wiping mechanism, an air knife mechanism, and a plasma cleaning mechanism; a curing unit, disposed near the rear end; the filler adhesive curing unit includes at least an IR curing lamp or a UV curing lamp.

[0014] The present invention also provides a method for forming a circuit protection layer of a display device, the display device including a display panel and a flexible circuit board on the side of the display panel, the flexible circuit board having a connection area connected to the display panel and a non-connection area connected to the connection area; forming the circuit protection layer using a printing apparatus for the circuit protection layer of the display device provided by the present invention; the method for forming the circuit protection layer includes the following steps: determining a predetermined coverage area of ​​the flexible circuit board, the predetermined coverage area at least covering the connection area; forming a first barrier wall on the side of the predetermined coverage area facing the display panel, and forming a second barrier wall on the side of the predetermined coverage area away from the display panel; the first barrier wall and the second barrier wall have the same height; forming the circuit protection layer between the first barrier wall and the second barrier wall, the circuit protection layer filling the space between the first barrier wall and the second barrier wall. During the formation of the first barrier wall and the second barrier wall, the operating parameters of the printing needles of different barrier wall printing units are the same.

[0015] Optionally, during the printing process of the printing needle printing the first barrier and the second barrier, the printing needle moves and prints along the width direction of the flexible circuit board; the method for forming the circuit protection layer of the display device further includes the following steps: scanning the connection area along the width direction of the flexible circuit board to determine the range of side warping in the width direction of the connection area; setting the printing parameters of the printing needle according to the range of side warping, so that during the movement of the printing needle along the width direction of the flexible circuit board, the height of the printing needle is adjusted to avoid the range of side warping.

[0016] Optionally, the printing needle begins printing after avoiding the side warping range during its movement from the free zone to above the connection zone; the printing needle ends printing before beginning to avoid the side warping range during its movement from above the connection zone to the free zone.

[0017] Optionally, a second spacing is provided between the printing needles of adjacent printing units in a horizontal direction perpendicular to the surface of the main support connecting the barrier printing unit. The second spacing is greater than the diameter of the printing needle. During the printing process of the printing needles printing the first barrier and the second barrier, one printing unit starts printing first after the printing needle of this unit moves to the printing position. Another printing unit moves to the printing position after the first printing unit has performed part of the printing action and then starts printing. The first printing unit completes the printing of the corresponding barrier first, and the second unit completes the printing of the corresponding barrier later.

[0018] The beneficial effects of the technical solution of this invention are as follows:

[0019] The present invention provides a printing apparatus for a circuit protection layer of a display device, comprising at least two barrier printing units. Two barriers can be printed in one step, forming a first barrier close to the display panel and a second barrier away from the display panel on a flexible circuit board. The area between the first and second barriers is designated as the coverage area for the circuit protection layer. A filler adhesive is printed by a filler adhesive printing unit to form the circuit protection layer. By controlling parameters, the dimensions of the two barriers can be made comparable, allowing the filler adhesive to flow naturally between them without abrupt slopes or depressions, resulting in a highly uniform circuit protection layer thickness. Because abrupt slopes are avoided, the overall thickness of the circuit protection layer can be reduced, as can the required slope width. Furthermore, the barrier close to the display panel prevents it from creeping onto the panel surface, thus not affecting subsequent encapsulation or even the display effect. Moreover, the at least two printing units can print at least two barriers simultaneously in one step, eliminating the need for sequential printing as in single-needle printing, effectively improving work efficiency. Furthermore, by setting the same operating parameters for the two printing needles, the dimensions of the formed barriers can be kept as consistent as possible. It is more conducive to the uniformity of the thickness of the line protection layer.

[0020] The present invention provides a method for forming a circuit protection layer for a display device. Using the printing device provided by the present invention, two baffles can be printed in one step. A first baffle close to the display panel and a second baffle far from the display panel are formed on a flexible circuit board. The area between the first and second baffles is used as the coverage area for the circuit protection layer. A filler adhesive is printed by a filler adhesive printing unit to form the circuit protection layer. By controlling parameters, the dimensions of the two baffles can be made comparable, allowing the filler adhesive to flow naturally between the two baffles without abrupt slopes or depressions. Therefore, the resulting circuit protection layer has a highly uniform thickness. Because there are no abrupt slopes, the overall thickness of the circuit protection layer can be reduced, and the required slope width can also be reduced. Furthermore, the presence of a baffle close to the display panel prevents it from creeping onto the display panel surface, thus not affecting subsequent encapsulation or even the display effect. Moreover, at least two printing units can print at least two baffles simultaneously in one step, eliminating the need for sequential printing as in single-needle printing, effectively improving work efficiency. Furthermore, by setting the same operating parameters for both printing needles, the size of the resulting retaining wall can be kept as consistent as possible. This is more conducive to the uniformity of the thickness of the circuit protection layer. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 A side view schematic diagram of the existing line protection layer structure;

[0023] Figure 2 A top view of the existing line protection layer structure;

[0024] Figure 3 A side view of the circuit protection layer formed by the printing apparatus and printing method of the display device of the present invention;

[0025] Figure 4 A top view of the circuit protection layer formed by the printing apparatus and printing method of the display device of the present invention;

[0026] Figure 5 A schematic diagram showing the state of the flexible circuit board of the display device after bending.

[0027] Figure 6This is a schematic diagram of the state during the formation of the barrier wall in the method for forming the circuit protection layer of the display device of the present invention;

[0028] Figure 7 This is a schematic diagram showing the state during the formation of the circuit protection layer in the method for forming the circuit protection layer of the display device of the present invention.

[0029] Figure 8 This is a partial front view of a printing apparatus for a circuit protection layer of a display device according to an embodiment of the present invention;

[0030] Figure 9 for Figure 8 Side view of the structure;

[0031] Figure 10 This is a schematic diagram of a printing needle avoiding the edge warping region of a flexible circuit board in a printing device for printing the circuit protection layer of a display device according to an embodiment of the present invention.

[0032] Figure 11 This is a schematic diagram of the printing apparatus for the circuit protection layer of a display device according to an embodiment of the present invention during the operation process;

[0033] Figure 12 This is a schematic diagram of a state in which two printing units asynchronously print according to the setting of a second spacing L in a method for forming a circuit protection layer of a display device according to an embodiment of the present invention.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1-Display panel; 2-Flexible circuit board; 21-Connection area; 22-Non-connection area; 31-First barrier; 32-Second barrier; 33-Circuit protection layer;

[0036] 100 - Main support; 210, 220 - Retaining wall printing unit; 211, 221 - Printing needles; 212, 222 - Needle drop motion axis; 213, 223 - Fixture; 300 - Filler adhesive printing unit; 230 - Spacing adjustment axis; 240 - Retaining wall curing component; 300 - Filler adhesive printing unit; 400 - Scanning unit; 500 - Pre-processing unit; 600 - Filler adhesive curing unit. Detailed Implementation

[0037] refer to Figures 1-2In existing methods, a flexible circuit board 2 is connected to the side of a display panel 1. The flexible circuit board 2 includes a connection area 21 connected to the display panel 1 and a non-connection area 22 that is not connected to the display panel 1. A circuit protection layer 33 is formed on the connection area 21, covering the connection area 21 and protecting the metal traces in the connection area 21. In addition, a first barrier 31 is set at a position away from the display panel 1 to prevent the fluid material forming the circuit protection layer 33 from flowing into the non-connection area and contaminating the devices in the non-connection area. In this method, due to the fluid nature of the material itself, the circuit protection layer exhibits a shape that is first concave and then sharply sloping near the display panel 1, and it is easy to rise to the surface of the display panel. The film thickness uniformity is poor, which may affect subsequent encapsulation and even the display effect.

[0038] Therefore, the present invention provides a printing apparatus and a method for forming a circuit protective layer for a display device, so as to solve the problem of poor uniformity of the thickness of the circuit protective layer film, which affects the packaging and may even affect the display effect.

[0039] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0042] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0043] Example 1

[0044] refer to Figures 8-11 and cooperation Figures 3-4 This embodiment provides a printing apparatus for a circuit protection layer of a display device.

[0045] The display device includes a display panel 1 and a flexible circuit board 2 on the side of the display panel. The flexible circuit board has a connection area 21 connected to the display panel 1 and a non-connection area 22 connected to the connection area 21. Metal traces that need to be protected are provided in the connection area 21.

[0046] The printing device includes:

[0047] Main support 100; the main support 100 has a front end and a rear end along the horizontal direction; Figure 11 For example, the left side of the diagram is the front end, and the right side is the back end.

[0048] At least two barrier printing units 210 and 220 are adapted to print barriers on the surfaces of the connecting area 21 and / or the non-connecting area 22, respectively; the printing unit includes printing needles 211 and 221; the printing units are spaced apart in the direction from the front end to the rear end of the main support.

[0049] A filler adhesive printing unit 300 is disposed at intervals from the retaining wall printing units 210 and 220 in the direction from the front end to the rear end of the main support 100, and is located between the rear end and the retaining wall printing units. It is adapted to print filler adhesive in the space between multiple retaining walls formed by multiple printing units to form the circuit protection layer; the circuit protection layer at least covers the connection area.

[0050] The printing apparatus for the circuit protection layer of the display device provided in this embodiment is equipped with at least two barrier printing units 210 and 220, which can print two barriers in one step. Figure 3 , Figure 4For example, a first barrier 31 close to the display panel 1 and a second barrier 32 far from the display panel 1 are formed on the flexible circuit board 2. The position between the first barrier 31 and the second barrier 32 is used as the coverage area for the circuit protection layer 33. The circuit protection layer 33 is formed by printing filler adhesive using the filler adhesive printing unit 300. The circuit protection layer 33 formed in this way can have its dimensions of the first barrier 31 and the second barrier 32 made comparable by controlling parameters. This allows the filler adhesive to flow naturally between the two barriers without abrupt slopes or depressions, resulting in a highly uniform film thickness for the circuit protection layer 33. Because there are no abrupt slopes, the overall film thickness of the circuit protection layer 33 can be reduced, as can the required slope width. Furthermore, the presence of the barrier close to the display panel 1 prevents it from creeping onto the surface of the display panel 1, thus not affecting subsequent encapsulation or even the display effect. Moreover, at least two printing units can print at least two barriers in one step, eliminating the need for sequential printing as in single-needle printing, effectively improving work efficiency. Furthermore, by setting the same operating parameters for both printing needles, the size of the resulting retaining wall can be kept as consistent as possible. This is more conducive to the uniformity of the thickness of the circuit protection layer.

[0051] Furthermore, the smaller the thickness and ramp width (the distance from the start of thickening to reaching the specified thickness) of the circuit protection layer 33, the smaller the bending area of ​​the flexible circuit board on the side of the display device can be. For details, refer to... Figure 5 The bending area includes the connection area 21 of the flexible circuit board and the circuit protection layer 33 on its surface. After the flexible circuit board is bent and folded (i.e., the non-connection area 22 is parallel to and stacked with the display panel 1, see reference...), Figure 5 The state shown will act as the "chin" of the display device (the area within the dashed box in the figure), protruding from the bottom of the display panel 1 and the non-connection area 22. It is easy to understand that the smaller the thickness of the circuit protection layer 33, the smaller the thickness of this part after folding. At the same time, because the overall thickness of the circuit protection layer 33 is reduced, a very high thickness is not required when printing the filler adhesive. Therefore, the distance from the start of thickening to reaching the specified thickness can be shortened, i.e., the ramp width can be reduced, and thus the overall size of the circuit protection layer 33 can be smaller. Consequently, the size of the connection area 21 under the circuit protection layer 33 can also be designed to be smaller. Therefore, in summary, the smaller the thickness and ramp width of the circuit protection layer 33, the smaller the bending area of ​​the flexible circuit board on the side of the device can be.

[0052] Further reference Figure 8 The retaining wall printing units 210 and 220 are equipped with clamps 213 and 223 for holding the printing needles 211 and 221.

[0053] Further reference Figure 8The retaining wall printing units 210 and 220 are equipped with needle-dropping motion shafts 212 and 222, which are parallel to the surface of the main support 100 connecting the retaining wall printing units 210 and 220 and perpendicular to the horizontal direction. The clamps 213 and 223 are adapted to move along the needle-dropping motion shafts 212 and 222. This allows the printing needles 211 and 221 to move vertically.

[0054] Further reference Figure 8 The printing needles 211 and 221 of adjacent retaining wall printing units 210 and 220 are spaced apart by a first gap in a horizontal direction parallel to the surface of the main support 100 that connects to the retaining wall printing unit, and the first gap is adjustable.

[0055] Specifically, at least one of the adjacent retaining wall printing units 210 and 220 is provided with a spacing adjustment shaft 230. For example, in this embodiment, the spacing adjustment shaft 230 is provided in unit 220. The spacing adjustment shaft 230 is arranged horizontally parallel to the surface of the main support 100 that connects to the retaining wall printing unit, and is movably connected to the clamps 223 / 213 (223 in this embodiment, but 213 in other embodiments, or both may have the spacing adjustment shaft 230). The clamps 223 are adapted to move horizontally along the spacing adjustment shaft to adjust the first spacing. In this way, the first spacing can be adjusted according to design needs, thereby controlling the size of the line protection layer.

[0056] Further reference Figure 8 The retaining wall printing unit is also provided with a retaining wall curing component 240, which is spaced apart from the printing needle 211 and connected to the clamp. Figure 8 The barrier wall curing component 240 can be provided in the barrier wall printing unit 210, the barrier wall printing unit 220, or both. The barrier wall printing unit equipped with the barrier wall curing component 240 can cure the material immediately after printing, allowing the barrier wall to form quickly and improving printing efficiency. The barrier wall curing component can be, for example, a UV curing lamp.

[0057] Further reference Figure 9Between the print pins of adjacent print units, there exists a second spacing L in a horizontal direction perpendicular to the surface of the main support connecting the retaining wall print unit. This second spacing L is larger than the diameter of the print pin. Since the horizontal dimension of the circuit protection layer 33 is sometimes small, it may be smaller than the sum of the radii of the two print pins, i.e., smaller than the diameter of one print pin. In this case, the two print pins cannot print synchronously side-by-side. Therefore, by setting the second spacing L, the two print pins are staggered, so that one starts printing first and the other starts printing later during movement, completing the printing asynchronously. This can meet the printing requirements of small-sized circuit protection layers 33.

[0058] Further reference Figure 11 The main support frame is further provided with the following features along the direction from the front end to the rear end:

[0059] The scanning unit 400 is used to scan the display device to which the circuit protection layer is to be formed in order to measure the required dimensions.

[0060] A pretreatment unit 500 is disposed between the scanning unit 400 and the barrier printing units 210 and 220; the pretreatment unit 500 includes at least one of the following: a solvent wiping mechanism, an air knife mechanism, and a plasma cleaning mechanism.

[0061] A filler adhesive curing unit 600 is disposed near the front end; the filler adhesive curing unit 600 includes at least an IR curing lamp or a UV curing lamp; it is used to cure the filler adhesive printed by the filler adhesive printing unit 300, so that the uncured filler adhesive is cured to form a circuit protection layer 33.

[0062] In actual operation, display device A is carried on carrier plate / conveyor belt B. The printing device moves relative to display device A along its length. First, it passes through scanning unit 400 to scan display device A and obtain relevant dimensional information. Then, it passes through pretreatment unit 500 for pretreatment such as solvent wiping, air knife surface cleaning, and plasma cleaning. Next, barrier printing units 210 and 220 print the first barrier and the second barrier. The size of the circuit protection layer is determined by the first spacing. Then, the printing device moves relative to display device A along its width to print the first barrier and the second barrier. Then, filler adhesive printing unit 300 prints the circuit protection layer 33 in the space between the first barrier and the second barrier. Finally, filler adhesive curing unit 600 cures the uncured circuit protection layer 33.

[0063] Compared with existing technologies Figure 1 , Figure 2 The structure, the circuit protection layer 33 printed using the printing device provided in this embodiment, such as... Figure 3 , Figure 4The structure shown in the prior art can only achieve a line protection layer 33 thickness of 50±15μm and a ramp width of >150μm; while the method of this embodiment can achieve a line protection layer 33 thickness of 20±10μm and a ramp width of ≤100μm.

[0064] Example 2

[0065] refer to Figure 6 , Figure 7 , combined Figure 3 and Figure 4 This embodiment provides a method for forming a circuit protection layer for a display device. The circuit protection layer is formed using the printing apparatus for the circuit protection layer of the display device provided in Embodiment 1.

[0066] The display device includes a display panel 1 and a flexible circuit board 2 on the side of the display panel 1. The flexible circuit board 2 has a connection area 21 connected to the display panel 1 and a non-connection area 22 connected to the connection area 21. The method for forming the circuit protection layer includes the following steps:

[0067] A predetermined coverage area is determined for the flexible circuit board 2, wherein the predetermined coverage area at least covers the connection area 21;

[0068] like Figure 6 As shown, a first barrier wall 31 is formed on the side of the predetermined coverage area facing the display panel 1, and a second barrier wall 32 is formed on the side of the predetermined coverage area away from the display panel 1; the first barrier wall 31 and the second barrier wall 32 have the same height;

[0069] like Figure 7 As shown, the line protection layer 33 is formed between the first retaining wall 31 and the second retaining wall 32, and the line protection layer 33 fills the space between the first retaining wall 31 and the second retaining wall 32;

[0070] During the formation of the first barrier wall 31 and the second barrier wall 32, the operating parameters of the printing needles of different barrier wall printing units are the same.

[0071] The method for forming a circuit protection layer in a display device provided in this embodiment uses the printing device provided by this invention to print the circuit protection layer. Two baffles can be printed in one step. A first baffle close to the display panel and a second baffle away from the display panel are formed on the flexible circuit board. The position between the first and second baffles is used as the coverage area for the circuit protection layer. A filler adhesive is printed by a filler adhesive printing unit to form the circuit protection layer. By controlling parameters, the dimensions of the two baffles can be made comparable, allowing the filler adhesive to flow naturally between the two baffles without abrupt slopes or depressions. Therefore, the resulting circuit protection layer has strong uniformity in film thickness. Because there are no abrupt slopes, the overall thickness of the circuit protection layer 33 can be reduced, and the required slope width can also be reduced. Furthermore, since the baffle close to the display panel exists, it will not climb onto the display panel surface, thus not affecting subsequent encapsulation or even the display effect. Moreover, at least two printing units can print at least two baffles simultaneously in one step, eliminating the need for sequential printing as in single-needle printing, effectively improving work efficiency. Furthermore, by setting the same operating parameters for both printing needles, the size of the resulting retaining wall can be kept as consistent as possible. This is more conducive to the uniformity of the thickness of the circuit protection layer.

[0072] Furthermore, during the process of printing the first barrier 31 and the second barrier 32, the printing needle moves and prints along the width direction of the flexible circuit board 2;

[0073] The method for forming the circuit protection layer of the display device further includes the following steps:

[0074] Scan the connection area 21 along the width direction of the flexible circuit board 2 to determine the range of side warping in the width direction of the connection area 21;

[0075] Based on the range of side warping, the printing parameters of the printing needle are set so that the height of the printing needle is adjusted during the movement of the printing needle along the width direction of the flexible circuit board 2 to avoid the range of side warping.

[0076] refer to Figure 10 Flexible printed circuit boards typically have some degree of warping along their width. Printing in this area can affect print quality, the shape of the printing baffle, and the warping can also obstruct the print needles, causing errors during printing. Therefore, pre-scanning and parameter setting are used to ensure the print needles avoid the warped areas.

[0077] Furthermore, as the print needle moves from the idle area to above the connecting area, it begins printing after avoiding the area of ​​side warping; as the print needle moves from above the connecting area to the idle area, it ends printing before beginning to avoid the area of ​​side warping. Since the warped area not only obstructs the print needle but also affects the final shape of the retaining wall when printing at the warped location, the warped area is avoided by pre-scanning and setting the print needle's operating parameters, allowing printing in the non-warped area. Figure 10 The area within the dashed line. From... Figure 4 As can be seen in the figure, the retaining wall and the line protection layer do not cover the area on the side in the width direction. Although the line protection layer 33 extends to the side, due to warping, it will eventually flow back to the center and will not extend beyond the range of the flexible circuit board.

[0078] refer to Figure 12 and combined Figure 9 As shown, a second spacing L is provided between the printing needles of adjacent printing units in a horizontal direction perpendicular to the surface of the main support 100 connecting the barrier printing units 210 and 220. The second spacing L is larger than the diameter of the printing needles 211 and 221. During the printing of the first barrier and the second barrier by the printing needles 211 and 221, one printing unit starts printing first after its printing needle moves to the printing position, and the other printing unit starts printing after the first printing unit has performed part of the printing action, moves to the printing position, and then starts printing. The first printing unit completes the printing of the corresponding barrier first, and the second printing unit completes the printing of the corresponding barrier later. By setting the second spacing L to stagger the two printing needles, one starts printing first and the other starts printing later during the movement, completing the printing asynchronously, which can meet the high-precision printing requirements of small-sized line protection layers 33.

[0079] refer to Figure 5 During the printing process of the retaining walls, by setting the second spacing L, the first retaining wall 31 starts printing first, followed by the second retaining wall 32. Printing begins after the first retaining wall 31 has printed a portion. This achieves asynchronous printing of the two retaining walls, avoiding interference between the two printing units when the size of the line protection layer 33 is small.

[0080] The specific printing process for a metal circuit protective layer is as follows:

[0081] 1) Fill the retaining wall printing units 210 and 220 and the filling adhesive printing unit 300 with the corresponding materials and start the printing device.

[0082] 2) The display device A, which is carried on the carrier plate / conveyor belt B, is transported to the ready position, and the display device A is adjusted to be horizontal.

[0083] 3) Move display device A to the scanning station, position display device A, and then scan display device A to obtain relevant dimensions. Based on this, calculate the required parameters, such as the first spacing, the second spacing, the distance between the printing needle and the display device needle surface, the predetermined coverage area size, the barrier height, the thickness of the circuit protection layer, the side warping range, and compensation parameters.

[0084] 4) Input the parameters into the printing device and set them so that the relevant units are adjusted to the corresponding positions to conform to the relevant setting parameters.

[0085] 5) Move the display device A to the pre-processing station, where the pre-processing unit 500 performs pre-processing on the display device A, including solvent wiping, air knife surface cleaning, plasma cleaning, etc.

[0086] 6) Move the display device A to the retaining wall printing station, where the retaining wall printing units 210 and 220 asynchronously print the first retaining wall 31 and the second retaining wall 32, while the retaining wall curing component 240 cures along with the printing.

[0087] 7) Move the display device A to the protective layer printing station, where the filler glue printing unit 300 prints the circuit protective layer 33.

[0088] 8) Move the display device A to the protective layer curing station, where the filler adhesive curing unit 600 cures the circuit protective layer 33.

[0089] 9) The display device A is conveyed away from each station and unloaded from the carrier plate / conveyor belt B, ready for printing the line protection layer of the next display device A.

[0090] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for forming a circuit protection layer of a display device, the display device comprising a display panel and a flexible circuit board on the side of the display panel, the flexible circuit board having a connection area with the display panel and a non-connection area connected to the connection area; characterized in that, A printing apparatus for forming a line protection layer using the following display device includes: Main support frame; the main support frame has a front end and a rear end along the horizontal direction; At least two barrier printing units are adapted to print barriers on the surfaces of the connecting area and / or non-connecting area respectively, and the movement trajectories of each printing unit are parallel during the printing process; each printing unit includes a printing needle; the printing units are spaced apart in the direction from the front end to the rear end of the main support. A filler adhesive printing unit is spaced apart from the retaining wall printing unit in the direction from the front end to the rear end of the main support, and is located between the rear end and the retaining wall printing unit. It is adapted to print filler adhesive in the space between multiple retaining walls formed by multiple printing units to form the circuit protection layer; the circuit protection layer at least covers the connection area. The method for forming the line protective layer includes the following steps: A predetermined coverage area of ​​the flexible circuit board is determined, wherein the predetermined coverage area at least covers the connection area; A first barrier wall is formed on the side of the predetermined coverage area facing the display panel, and a second barrier wall is formed on the side of the predetermined coverage area away from the display panel; the first barrier wall and the second barrier wall have the same height and extend in parallel directions; The line protection layer is formed between the first retaining wall and the second retaining wall, and the line protection layer fills the space between the first retaining wall and the second retaining wall; During the formation of the first and second barrier walls, the operating parameters of the printing needles in different barrier wall printing units are the same; During the printing process of the first and second retaining walls, one printing unit starts printing first after the printing needle of the unit moves to the printing position, and another printing unit moves to the printing position after the first printing unit has performed part of the printing action, and then starts printing; the first printing unit completes the printing of the corresponding retaining wall first, and the second unit completes the printing of the corresponding retaining wall later.

2. The method for forming a circuit protection layer of a display device according to claim 1, characterized in that, The retaining wall printing unit is equipped with a clamp for holding the printing needle.

3. The method for forming a circuit protection layer of a display device according to claim 2, characterized in that, The retaining wall printing unit is provided with a needle-falling motion axis, which is parallel to the surface of the main support connecting the retaining wall printing unit and perpendicular to the horizontal direction; the clamp is adapted to move along the needle-falling motion axis.

4. The method for forming a circuit protection layer of a display device according to claim 3, characterized in that, The printing needles of adjacent retaining wall printing units are spaced apart by a first gap in a horizontal direction parallel to the surface of the main support connecting the retaining wall printing unit, and the first gap is adjustable.

5. The method for forming a circuit protection layer of a display device according to claim 4, characterized in that, In each of the adjacent retaining wall printing units, at least one is provided with a spacing adjustment shaft. The spacing adjustment shaft is arranged horizontally parallel to the surface of the main support connecting the retaining wall printing unit and is movably connected to the clamp. The clamp is adapted to move horizontally along the spacing adjustment shaft to adjust the first spacing.

6. The method for forming a circuit protection layer of a display device according to claim 2, characterized in that, The retaining wall printing unit is also provided with a retaining wall curing component, which is spaced apart from the printing needle and connected to the clamp.

7. The method for forming a circuit protection layer of a display device according to claim 3, characterized in that, Between the printing needles of adjacent printing units, there is a second gap in the horizontal direction perpendicular to the surface of the main support connecting the retaining wall printing unit, and the second gap is greater than the diameter of the printing needle.

8. The method for forming a circuit protection layer of a display device according to any one of claims 2-7, characterized in that, The main support frame is further provided with the following features along the direction from the front end to the rear end: A scanning unit is disposed near the front end; the scanning unit is used to scan the display device to measure the required dimensions; A pretreatment unit is disposed between the scanning unit and the barrier printing unit; the pretreatment unit includes at least one of the following: a solvent wiping mechanism, an air knife mechanism, and a plasma cleaning mechanism; A filler adhesive curing unit is disposed near the rear end; the filler adhesive curing unit includes at least an IR curing lamp or a UV curing lamp.

9. The method for forming a circuit protection layer of a display device according to claim 1, characterized in that, During the printing process of the printing needle printing the first barrier and the second barrier, the printing needle moves along the width direction of the flexible circuit board to print; The method for forming the circuit protection layer of the display device further includes the following steps: Scan the connection area along the width direction of the flexible circuit board to determine the range of side warping in the width direction of the connection area; Based on the extent of side warping, the printing parameters of the printing needle are set so that the height of the printing needle is adjusted as it moves along the width direction of the flexible circuit board to avoid the extent of side warping.

10. The method for forming a circuit protection layer of a display device according to claim 9, characterized in that, As the printing needle moves from the idle area to above the connection area, it begins printing after avoiding the area of ​​side warping. As the printing needle moves from above the connection area to the free zone, printing ends before it begins to avoid the side warping range.

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