Silicone encapsulation device and method for flexible electrode structure reinforcement

Abstract

This application discloses a silicone coating device and method for reinforcing the structure of flexible electrodes. The coating device includes: a base with a filling groove for silicone coating on the lower side of the electrode; a middle layer gasket with a first connector avoidance window and a filling window for silicone coating on the upper side of the electrode, the first connector avoidance window being used to avoid the electrode connector area of ​​the flexible electrode to be coated; and a top cover with a second connector avoidance window corresponding to the first connector avoidance window, the second connector avoidance window being used to avoid the electrode connector area. The top cover is detachably connected to the base and applies downward pressure to the middle layer gasket after connection. The filling groove and the filling window cooperate to define the position, outline, and thickness of the silicone coating area, which can be a single-sided, double-sided, partial, or entire area of ​​the flexible electrode to be coated. This application can achieve controllable silicone coating of flexible electrodes on one side, two sides, partially, or entirely, structurally enhancing the overall mechanical strength of the electrode and solving the problem of easy breakage and fracture of thin film substrates under stretching and bending.

Description

Technical Field

[0001] This application relates to the fields of brain-computer interface and implantable neural microelectrode technology, and more specifically, to a silicone coating device and coating method for enhancing flexible electrode structures. Background Technology

[0002] Implantable flexible microelectrodes are increasingly used in neuroscience research, clinical practice in brain-computer interfaces, and animal electrophysiological experiments. However, most implantable flexible microelectrodes are prone to damage to their main structure during and after implantation due to stress such as stretching or bending, which seriously affects clinical reliability and experimental efficiency.

[0003] Specifically, most commonly used implantable flexible microelectrodes currently employ polymer thin films with a thickness of only a few micrometers as a substrate, onto which conductive materials with a thickness of several hundred nanometers are deposited or embedded. These structures face the following common technical bottlenecks: low mechanical strength of the electrode structure, making it prone to damage or even breakage under tensile and bending conditions; limited interfacial bonding between the conductive layer and the flexible substrate, leading to delamination, microcracks, or peeling during cyclic deformation, resulting in significantly increased resistance or circuit failure. Furthermore, the electrode material itself lacks effective protection, and exposure to humid bodily fluids can cause liquid infiltration and electrochemical corrosion, affecting the long-term reliability of the electrode. Summary of the Invention

[0004] The main objective of this application is to provide a silicone coating device and coating method for reinforcing flexible electrode structures, in order to solve the problems of implantable flexible microelectrodes in related technologies, such as low strength of ultrathin polymer substrates, easy breakage when bent and stretched; weak bonding between conductive layer and substrate interface, easy delamination and peeling due to repeated deformation, resulting in circuit failure; lack of protection, easy leakage and corrosion in body fluid environment, and insufficient long-term reliability.

[0005] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description or may be learned by practice of this application.

[0006] According to a first aspect of this application, a silicone coating device for reinforcing flexible electrode structures is provided, comprising: The base has a filling groove for silicone coating on the lower side of the electrodes; The middle layer pad is provided with a first connector avoidance window and a silicone coating filling window on the upper side of the electrode. The first connector avoidance window is used to avoid the electrode connector area of ​​the flexible electrode to be coated. The top cover is provided with a second connector avoidance window corresponding to the first connector avoidance window. The second connector avoidance window is used to avoid the electrode connector area. The top cover is detachably connected to the base and applies downward pressure to the middle layer gasket after connection. The filling groove and the filling window cooperate with each other to define the position, outline and thickness of the silicone coating area, which is a single side, double side, partial or whole area of ​​the flexible electrode to be coated.

[0007] This embodiment precisely defines the position, outline, and thickness of the silicone coating area through the combination of the base filling groove, the middle layer gasket filling window, and the upper and lower connector avoidance windows. The removable top cover presses the middle layer gasket, ensuring proper mold positioning and uniform adhesive layer thickness. It avoids the need for additional cutting of the electrode connector and enables controllable silicone coating of the flexible electrode on one side, both sides, partially, or entirely, structurally enhancing the overall mechanical strength of the electrode and solving the problem of easy breakage and fracture of the thin film substrate due to stretching and bending. At the same time, the overall silicone coating forms a protective layer, preventing the infiltration of body fluids, resisting electrochemical corrosion, and improving long-term operational reliability. In addition, after silicone coating the upper side of the flexible electrode through the filling window, it can strengthen the interfacial adhesion constraint between the conductive layer in the flexible electrode and the flexible substrate, suppressing interfacial delamination, microcracks, and peeling caused by cyclic stress deformation, and avoiding sudden resistance changes or open circuit failures.

[0008] In one exemplary embodiment of this application, a lateral filling gap is provided between the filling groove and the area to be covered, the lateral filling gap being used to accommodate the covering material covering the side of the area to be covered.

[0009] This embodiment allows silicone to simultaneously cover the sides of the electrode by reserving lateral filling gaps, achieving circumferential full encapsulation, eliminating exposed gaps at the electrode edges, further improving the interface bonding strength and overall sealing protection, effectively preventing body fluids from seeping in from the sides and eroding the electrode, while also enhancing the electrode sides' resistance to bending and tearing.

[0010] In one exemplary embodiment of this application, the base is provided with multiple independent filling grooves, the middle layer pad is provided with multiple independent silicone filling windows and multiple independent first connector avoidance windows, and the top cover is provided with multiple second connector avoidance windows, so as to realize the synchronous coating of multiple flexible electrodes to be coated.

[0011] This embodiment uses a base, a middle layer pad, and a top cover to set up multiple independent grooves and avoidance windows, which can complete the simultaneous silicone coating of multiple flexible electrodes at one time. This enables batch molding with good consistency, greatly improving processing efficiency. Moreover, the coating of each electrode does not interfere with each other, ensuring that the coating accuracy and structural reinforcement effect of a single electrode are not affected.

[0012] In one exemplary embodiment of this application, the base, the middle gasket, and the top cover are aligned and assembled using a positioning structure.

[0013] In this embodiment, the base, the middle layer gasket, and the top cover are precisely aligned and assembled using a positioning structure to avoid mold closing misalignment and ensure that the filling groove and the filling window are coaxially aligned. This results in a regular coating contour, with no uneven thickness or missing glue in the adhesive layer, and stably guarantees the consistency of electrode coating accuracy, structural reinforcement, and sealing protection, thereby reducing the defect rate. The positioning structure may include positioning holes, snap-fit ​​devices, etc.

[0014] According to a second aspect of this application, a method for silicone coating to enhance flexible electrode structures is provided, employing the aforementioned silicone coating apparatus, and comprising the following steps: Place the flexible electrode to be coated into the glue filling groove of the base; Place the middle layer pad above the flexible electrode to be covered, so that the first connector avoids the opening of the flexible electrode to be covered and the filling window corresponds to the area to be covered on the upper side of the electrode. Fill the filling window with silicone to cover the area to be coated on the upper side of the electrode; Close the top cover and avoid the electrode connector through the second connector avoidance window; After the silicone has cured, disassemble the device and remove the coated flexible electrode.

[0015] This embodiment utilizes the first connector avoidance window and the second connector avoidance window to precisely avoid the electrode connector on the flexible electrode to be covered, eliminating the need for subsequent trimming that could damage the electrode. During the covering process, the silicone is filled and molded from top to bottom, precisely covering the upper area of ​​the electrode. The molding thickness and contour are uniform and standardized, forming a regular silicone coating layer on the upper area of ​​the flexible electrode, improving the overall mechanical strength of the electrode, making it resistant to stretching and bending and less prone to breakage. At the same time, the silicone coating layer on the upper area of ​​the flexible electrode adheres tightly to the electrode surface, constraining the interface between the conductive layer and the substrate, suppressing delamination, peeling, and open circuit problems caused by cyclic deformation, and forming a surface protection layer to prevent the corrosion of body fluids, thus improving long-term reliability.

[0016] According to a third aspect of this application, a method for silicone coating to enhance flexible electrode structures is provided, employing the aforementioned silicone coating apparatus, and comprising the following steps: Fill the area to be covered on the lower side of the electrode with silicone in the filling groove of the base; Place the flexible electrode to be coated in the filling tank, so that the area to be coated is on the underside of the silicone coated electrode; Close the top cover and avoid the electrode connector through the second connector avoidance window; After the silicone has cured, disassemble the device and remove the coated flexible electrode.

[0017] In this embodiment, silicone is first pre-filled into the glue-filling groove of the base, and then the flexible electrode to be coated is placed to achieve the lower side coating first. With the upper cover, the mold is closed and shaped, and the lower silicone adheres to and wraps the bottom surface of the electrode. By using the avoidance window to avoid interference with the electrode connector, the assembly and alignment are simple and the molding consistency is high. In addition, by forming a silicone coating layer in the lower area of ​​the electrode, the thin film substrate structure is reinforced from the bottom, improving the bending resistance and tear resistance. At the same time, the silicone coating layer at the bottom can prevent body fluid from seeping in from the bottom, improving the electrochemical corrosion problem.

[0018] In one exemplary embodiment of this application, the flexible electrode to be covered includes an electrode array region, a flexible connection line region, and an electrode connection region. The area to be covered on the lower side of the electrode includes at least the lower surface of one or more of the electrode array region, the flexible connection line region, and the electrode connection region.

[0019] In this embodiment, any one or more areas among the electrode array area, flexible circuit area, and connection interface area can be selectively covered as needed, without the need for full coverage. Therefore, the mechanically weak sections of the electrode can be targeted for reinforcement. While ensuring structural enhancement, anti-delamination and corrosion resistance, the original electrical and mechanical properties of the areas that do not need to be covered are preserved, taking into account both structural reliability and electrode functional adaptability, reducing material consumption and adapting to different operating conditions.

[0020] According to a fourth aspect of this application, a method for silicone coating to enhance flexible electrode structures is provided, employing the aforementioned silicone coating apparatus, comprising the following steps: Fill the area to be covered on the lower side of the electrode with silicone in the filling groove of the base; Place the flexible electrode to be coated in the filling tank, so that the area to be coated is on the underside of the silicone coated electrode; After the silicone in the area to be coated on the lower side of the electrode has cured, place the middle layer pad above the flexible electrode to be coated, so that the first connector avoids the opening and avoids the electrode connector, and the silicone filling window corresponds to the area to be coated on the upper side of the electrode. Fill the silicone filling window with silicone to cover the area to be coated on the upper side of the electrode; Close the top cover so that the second connector avoids the opening and avoids the electrode connector; After the silicone has cured, disassemble the device and remove the coated flexible electrode.

[0021] In this embodiment, a flexible electrode double-sided stepwise encapsulation process is employed. The device's filling groove and filling window precisely define the encapsulation range and thickness of the silicone on the upper and lower sides of the flexible electrode, while the avoidance window facilitates mold closing and curing. This achieves a controllable, integrated silicone encapsulation of the flexible electrode on both sides, significantly improving overall mechanical strength and making it resistant to repeated stretching and bending without breakage. The double-sided adhesive layer firmly binds the conductive layer to the substrate interface, comprehensively suppressing microcracks, delamination, and peeling failure. The full-circumference sealing protects against moisture and body fluids, effectively preventing leakage and electrochemical corrosion, and significantly improving long-term operational stability after implantation.

[0022] In one exemplary embodiment of this application, the flexible electrode to be covered includes an electrode array region, a flexible connection line region, and an electrode connection region. The area to be covered on the lower side of the electrode includes at least the lower surface of one or more of the electrode array region, the flexible connection line region, and the electrode connection region. The area to be covered on the upper side of the electrode includes at least the upper surface of the flexible connection line area.

[0023] In this embodiment, the silicone coating area on the lower side of the flexible electrode can selectively coat the array area, circuit area, and interface area, while the upper side is only selectively coated with weak sections of the flexible connection circuit. This precise focus on mechanically vulnerable flexible circuit areas provides enhanced protection, strengthening the circuit segments' resistance to deformation, delamination, and corrosion, while avoiding unnecessary redundant coating. It balances structural reinforcement, electrical performance integrity, and overall flexibility adaptability, making it suitable for complex deformation scenarios of implanted flexible electrodes.

[0024] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0025] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application. In the drawings: Figure 1 This is a schematic diagram of the structure of the flexible electrode to be coated according to the embodiments of this application; Figure 2 This is an exploded structural diagram of the silicone coating device according to the embodiments of this application; Figure 3 This is a schematic diagram of the assembled structure of the silicone coating device according to the embodiments of this application; Figure 4 This is a schematic diagram of the structure of a flexible electrode with a silicone coating layer according to an embodiment of this application; Figure 5This is an exploded structural diagram of a flexible electrode with a silicone coating layer of different morphology according to an embodiment of this application; Figure 6 This is an exploded structural diagram of the silicone coating device according to another embodiment of this application; Figure 7 This is a schematic diagram of the silicone coating process according to one embodiment of this application; Figure 8 This is an exploded structural diagram of a flexible electrode with a silicone coating layer according to an embodiment of this application; Figure 9 This is an exploded structural diagram of a flexible electrode with a silicone coating layer according to another embodiment of this application; Figure 10 This is an exploded structural diagram of a flexible electrode with a silicone coating layer according to another embodiment of this application; Figure 11 This is a schematic diagram of the silicone coating process according to another embodiment of this application; Figure 12 This is an exploded structural diagram of a flexible electrode with a silicone coating layer according to an embodiment of this application; Figure 13 This is an exploded structural diagram of a flexible electrode with a silicone coating layer according to another embodiment of this application; Among them, 1. Flexible electrode to be coated; 2. Silicone coating layer; 11. Electrode array area; 12. Flexible connection line area; 13. Electrode connection area; 31. Base; 311. Filling groove; 32. Middle layer gasket; 321. First connector avoidance window; 322. Filling window; 33. Top cover; 331. Second connector avoidance window. Detailed Implementation

[0026] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed descriptions will be omitted. Furthermore, the drawings are merely illustrative of this application and are not necessarily drawn to scale.

[0027] Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of an icon to another, these terms are used only for convenience, such as according to the orientation of the examples in the accompanying drawings. It is understood that if the device of the icon is flipped so that it is upside down, the component described as "upper" will become the component described as "lower." When a structure is "upper" of another structure, it may mean that the structure is integrally formed on the other structure, or that the structure is "directly" mounted on the other structure, or that the structure is "indirectly" mounted on the other structure through another structure.

[0028] The terms “a,” “one,” “the,” and “at least one” are used to indicate the existence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first” and “second” are used only as markers and are not a limitation on the number of objects.

[0029] Furthermore, the terms "set up," "equipped with," "connected," and "fixed" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0030] In addition, the term "multiple" should mean two or more.

[0031] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0032] Example 1 This embodiment provides a silicone coating device for reinforcing flexible electrode structures, wherein the flexible electrode 1 to be coated includes, but is not limited to, thin-film electrodes and microneedle electrodes, as shown in... Figure 1 Taking the thin-film electrode shown as an example, it mainly consists of an electrode array region 11, a flexible connection line region 12, and an electrode connection region 13. The upper surface of the electrode connection region 13 has a protruding electrode connector. The electrode array region 11 is provided with a number of electrodes for generating or receiving electrical signals. The flexible connection line region 12 includes a number of leads connecting the electrodes and the electrode connectors.

[0033] like Figure 2As shown, the silicone coating device mainly comprises three parts: a base 31, a middle layer gasket 32, and a top cover 33. The base 31 has a filling groove 311 for silicone coating of the flexible electrode. During the silicone coating process, the flexible electrode 1 to be coated can be completely embedded in the filling groove 311, with the electrode connector of the flexible electrode 1 located at the top. Silicone can be pre-injected into the filling groove 311, and then the flexible electrode 1 to be coated is placed into the filling groove 311, allowing the uncured silicone to coat the area to be coated on the electrode to form a silicone coating layer 2. The area to be coated on the electrode may include the lower surface of the electrode array area 11, or the lower surface of the flexible connection line area 12, or the lower surface of the electrode connection area 13, or the entire lower surface of the flexible electrode 1 to be coated. A lateral filling gap can be provided between the filling groove 311 and the flexible electrode 1 to be coated. The lateral filling gap is used to accommodate the coating material covering the side of the area to be coated, so as to realize the lateral silicone wrapping of the flexible electrode 1 to be coated.

[0034] The middle layer gasket 32 ​​is stacked on top of the base 31 and has a first connector avoidance window 321 and a filling window 322. The first connector avoidance window 321 can accurately avoid the electrode connector of the flexible electrode 1 to be covered, and the middle layer gasket 32 ​​can fit against the upper surface of the base 31, avoiding obstruction of the connector structure and silicone coverage during the covering process, ensuring that the electrode interface function is not affected. The position of the filling window 322 corresponds to the flexible connection line area 12 of the flexible electrode 1 to be covered, and its width is greater than or equal to the width of the flexible connection line area 12. After the middle layer gasket 32 ​​is assembled, silicone can be injected into the filling window 322. Under the constraint of the filling window 322, the silicone covers the upper surface of the flexible connection line area 12.

[0035] When the width of the filling window 322 is greater than the width of the flexible connection line area 12, a lateral filling gap is set between the filling groove 311 and the flexible electrode 1 to be covered, and silicone is also pre-injected into the filling groove 311, the silicone injected through the filling window 322 can combine with the silicone in the filling groove 311, thereby completely wrapping the flexible connection line area 12 in the circumferential direction.

[0036] The upper cover 33 has a matching second connector clearance window 331 corresponding to the first connector clearance window 321 of the middle layer gasket 32, similarly achieving clearance for the electrode connector, allowing the upper cover 33 to be pressed onto the upper surface of the middle layer gasket 32 ​​after assembly. The upper cover 33 and the base 31 adopt a detachable connection structure, and positioning assembly can be achieved through a positioning structure. After the upper cover 33 is closed onto the base 31, it can apply uniform downward pressure to the middle layer gasket 32 ​​stacked in the middle, making the overall assembly tight and without offset gaps (e.g. Figure 3(As shown). Furthermore, after assembly, the inner surface of the top cover 33 can seal the filling window 322 on the middle gasket 32, thus stabilizing the silicone molding within the filling window 322. The positioning structure may include positioning holes or positioning clips. Figure 4 A flexible electrode with a silicone coating layer 2 is shown using the silicone coating device of this application.

[0037] In this embodiment, the silicone coating device can flexibly achieve single-sided coating of the flexible electrode 1 to be coated (e.g., Figures 8 to 10 As shown, silicone coating is performed only on one side of the flexible electrode 1 to be coated, or on both sides (as shown). Figure 12 As shown, silicone coating can be applied to the upper and lower surfaces of the flexible electrode 1 to be coated, or partially coated (silicone coating can be applied to specific locations of the flexible electrode 1 to be coated), or completely coated (e.g., silicone coating can be applied to the entire electrode 1). Figure 13 As shown, the molding process involves silicone coating the entire area of ​​the flexible electrode 1 to be coated, excluding the upper surface of the electrode array region 11 and the electrode connection region 13.

[0038] It is understandable that when the flexible electrode 1 to be coated is a microneedle electrode, the middle layer pad 32 and the top cover 33 need to have additional windows in the microneedle area of ​​the corresponding microneedle electrode to avoid the microneedles.

[0039] In one embodiment, the inner contours of the filling groove 311 and the filling window 322 are designed to conform to the shape of the flexible electrode 1 to be covered. For example, the flexible connection line area 12 of the flexible electrode 1 to be covered is set to a square, the inner contour of the area in the filling groove 311 corresponding to the flexible connection line area 12 is also square, and the inner contour of the filling window 322 is also square.

[0040] In one embodiment, the inner contours of the filling groove 311 and the filling window 322 may not be designed to conform to the shape of the flexible electrode 1 to be covered, but rather designed according to actual needs. For example, as Figure 5 The four forms shown are a, b, c, and d, where the silicone coating layer 2 shown in figure d has a suture hole.

[0041] In this embodiment, the silicone coating device, through the split structure of the base 31, the middle gasket 32, and the top cover 33, can precisely control the silicone coating molding accuracy, forming a regular silicone protective reinforcement layer on the surface of the flexible electrode 1 to be coated. This effectively improves the overall mechanical strength of the flexible electrode and alleviates the problem of easy breakage and fracture when the electrode is bent and stretched. At the same time, the silicone coating tightly constrains the interface between the conductive layer and the flexible substrate, suppressing delamination, cracking, and peeling failures that occur under cyclic deformation. It can also form a sealed protection for the electrode, blocking liquid infiltration and electrochemical corrosion in the implanted body fluid environment, and improving the long-term working reliability of the flexible electrode.

[0042] In one implementation, such as Figure 6As shown, several independent filling grooves 311 are arranged side by side on the base 31. Each filling groove 311 is separated from each other and is not connected to each other, and can be used to place a single flexible electrode 1 to be covered. The middle layer pad 32 is provided with an equal number of independent silicone filling windows 322 and independent first connector avoidance windows 321 in the same position according to the arrangement of the independent filling grooves 311 on the base 31. The top cover 33 is provided with the same number of second connector avoidance windows 331 that are aligned.

[0043] During assembly, each set of corresponding independent filling grooves 311, silicone filling windows 322, and upper and lower connector clearance windows forms an independent silicone encapsulation molding station. The stations are structurally separated, and the molding areas do not interfere with each other. This multi-station array layout allows multiple flexible electrodes 1 to be encapsulated to be placed simultaneously within the device, completing alignment, filling, mold closing, and curing in one go, enabling simultaneous silicone encapsulation of multiple flexible electrodes. This retains the precise positioning, contour, and adhesive layer thickness control required for single-electrode encapsulation while enabling batch synchronous operation, ensuring consistent encapsulation, structural reinforcement, and sealing protection for each flexible electrode, significantly improving processing efficiency and meeting the needs of industrial-scale mass production.

[0044] Example 2 Figure 7 This illustrates the encapsulation process in this embodiment. Figure 8 This illustration shows a flexible electrode obtained according to the coating process. This embodiment provides a single-sided silicone coating method for reinforcing the structure of a flexible electrode, specifically for coating the upper side of the flexible electrode 1 to be coated with silicone, using the silicone coating apparatus from Embodiment 1, and the following steps: First, the flexible electrode 1 to be coated is placed inside the glue filling groove 311 of the base 31. The glue filling groove 311 is used to position and limit the bottom of the flexible electrode 1 to be coated, ensuring that the electrode is placed in a regular position without deviation.

[0045] Next, the middle layer pad 32 is stacked on top of the flexible electrode 1 to be covered, and precisely aligned so that the first connector avoidance window 321 on the middle layer pad 32 corresponds exactly to the avoidance electrode connector, so as to prevent the electrode connector from being blocked or covered by silicone; at the same time, the filling window 322 of the middle layer pad 32 is precisely aligned with the area to be covered on the upper side of the electrode (i.e. the upper surface of the flexible connection line area 12), defining the molding range of the upper silicone.

[0046] Subsequently, silicone filler is injected into the area to be coated on the upper side of the electrode through the filling window 322, so that the silicone filler is evenly spread and completely covers the area to be coated on the upper side of the electrode. The contour, thickness and boundary of the silicone coating are defined by the cooperation of the filling groove 311 and the filling window 322.

[0047] Then the cover 33 of the device is closed. The cover 33 avoids the electrode connector again through the second connector avoidance window 331 set by itself, so as to prevent the assembly squeezing and damage to the electrode connector. The cover 33 and the base 31 are detachably locked and connected. At the same time, a uniform downward pressure is applied to the middle layer gasket 32 ​​to make the structure of each layer fit tightly and avoid silicone overflow, misalignment and deformation.

[0048] Keep the mold closed until the silicone is completely cured and molded. After curing, remove the top cover 33 and the middle layer gasket 32, and take out the finished product from the glue filling groove 311 of the base 31. This completes the silicone coating structure reinforcement processing of the flexible electrode.

[0049] This method relies on the device's precise positioning and avoidance structure, and the process steps are simple and regular. It can achieve controllable silicone encapsulation molding on the upper side of the flexible electrode. The molded encapsulation layer has uniform thickness and regular boundaries, which can effectively improve the mechanical strength of the flexible electrode, enhance the interlayer bonding force, and form a sealed protective structure, thereby improving the overall performance of the implanted flexible electrode in terms of bending resistance, delamination prevention, and corrosion resistance.

[0050] Example 3 Figure 9 This illustration shows the flexible electrode prepared in this embodiment. Specifically, this embodiment provides a method for single-sided silicone coating to enhance the structure of a flexible electrode. Specifically, the lower side of the flexible electrode 1 to be coated is coated with silicone, using the silicone coating device in Embodiment 1, and the following steps are performed: First, suitable silicone is pre-filled inside the filling groove 311 of the base 31, corresponding to the area to be covered on the lower side of the flexible electrode 1. The contour of the filling groove 311 limits the laying range and thickness of the silicone. In this embodiment, the flexible electrode 1 to be covered includes an electrode array region 11, a flexible connection line region 12, and an electrode connection region 13. The area to be covered on the lower side of the electrode includes at least the lower surface of one or more of the electrode array region 11, the flexible connection line region 12, and the electrode connection region 13. When silicone is applied to the lower surface of the flexible connection line region 12, the silicone may only fill the position in the filling groove 311 corresponding to the flexible connection line region 12. When silicone is applied to the lower surfaces of the electrode array region 11, the flexible connection line region 12, and the electrode connection region 13, the silicone completely fills the filling groove 311.

[0051] Next, the flexible electrode 1 to be coated is placed stably in the filling groove 311, so that the area to be coated on the lower side of the electrode is in contact with the filled silicone. The silicone naturally wraps and adheres to the area to be coated on the lower side of the electrode, thus completing the silicone pre-coating and positioning of the bottom surface of the electrode.

[0052] Afterwards, the cover 33 of the device is closed. The cover 33 also aligns and avoids the electrode connector through the second connector avoidance window 331. The cover 33 and the base 31 are detachably assembled and locked, so that the base 31 is tightly attached to the flexible electrode 1 to be covered, preventing silicone overflow, displacement and molding deformation.

[0053] Maintain the mold closed state until the silicone in the filling groove 311 is completely cured and shaped; after curing, disassemble the top cover 33 and remove the processed flexible electrode from the filling groove 311 of the base 31, thus completing the silicone coating and structural reinforcement of the lower part of the electrode.

[0054] When the silicone is filled only in the filling groove 311 at the position corresponding to the flexible connection line area 12, the following can be obtained: Figure 9 The image shows a flexible electrode with a silicone coating layer 2. When the silicone filler 311, the silicone can coat the lower surfaces of the electrode array region 11, the flexible connection line region 12, and the electrode connection region 13 of the flexible electrode, resulting in the following: Figure 10 The flexible electrode shown has a silicone coating layer 2.

[0055] This method adopts a process path of first filling with glue, then placing the electrode, and finally molding and curing. Relying on the precise positioning of the device tank and the avoidance window, the silicone coating layer 2 on the lower side of the electrode after molding is uniform, regular and tightly attached. This can effectively strengthen the flexible electrode substrate structure, improve the bending and tear resistance, enhance the bonding strength between the conductive layer and the substrate interface, and form a bottom seal protection to prevent the infiltration and corrosion of body fluids, thus ensuring the long-term reliability of the implantable flexible electrode.

[0056] Example 4 Figure 11 This illustrates the encapsulation process in this embodiment. Figure 12 and Figure 13 This illustration demonstrates the fabrication of the flexible electrode in this embodiment. Specifically, this embodiment provides a double-sided silicone coating method for reinforcing the structure of a flexible electrode. Specifically, silicone coating is applied to the upper and lower sides of the flexible electrode 1 to be coated, using the silicone coating apparatus from Embodiment 1, and the following steps are followed: First, suitable silicone is pre-filled inside the filling groove 311 of the base 31, corresponding to the area to be covered on the lower side of the flexible electrode 1. The contour of the filling groove 311 limits the laying range and thickness of the silicone. In this embodiment, the flexible electrode 1 to be covered includes an electrode array region 11, a flexible connection line region 12, and an electrode connection region 13. The area to be covered on the lower side of the electrode includes at least the lower surface of one or more of the electrode array region 11, the flexible connection line region 12, and the electrode connection region 13. When silicone is applied to the lower surface of the flexible connection line region 12 of the flexible electrode 1, the silicone may only fill the position in the filling groove 311 corresponding to the flexible connection line region 12. When silicone is applied to the lower surfaces of the electrode array region 11, the flexible connection line region 12, and the electrode connection region 13, the silicone completely fills the filling groove 311.

[0057] Next, the flexible electrode 1 to be coated is placed stably in the filling groove 311, so that the area to be coated on the lower side of the electrode is in contact with the filled silicone. The silicone naturally wraps and adheres to the area to be coated on the lower side of the electrode, completing the silicone pre-coating and positioning of the bottom surface of the electrode. At the same time, the filling groove 311 is used to position the entire electrode to prevent the electrode from shifting during subsequent operations.

[0058] After the silicone in the area to be coated on the lower side of the electrode has cured, the middle layer pad 32 is stably stacked on top of the flexible electrode 1 to be coated and precisely aligned and assembled so that the first connector avoidance window 321 on the middle layer pad 32 precisely corresponds to the electrode connector of the flexible electrode 1 to be coated, achieving complete avoidance, preventing the connector from being covered and contaminated with silicone, ensuring the integrity of the electrode interface structure, and precisely aligning the filling window 322 on the middle layer pad 32 with the area to be coated on the upper side of the electrode, clearly defining the coating range and outline of the silicone on the upper side of the electrode, providing precise limits for the upper side filling.

[0059] After the middle layer pad 32 is aligned, silicone is slowly injected into the filling window 322 of the middle layer pad 32 to ensure that the silicone can be evenly spread throughout the filling window 322 and completely cover the area to be covered on the upper side of the electrode to be covered. At the same time, silicone overflows from the filling window 322 to ensure that the thickness of the upper silicone coating layer matches the thickness of the lower silicone coating layer, forming a symmetrical and uniform double-coverage structure.

[0060] Next, the top cover 33 is aligned with the middle layer gasket 32 ​​and the base 31 and closed. During the closing process, ensure that the second connector avoidance window 331 on the top cover 33 precisely aligns with the first connector avoidance window 321 and the electrode connector on the middle layer gasket 32, again achieving avoidance of the electrode connector and preventing the top cover 33 from squeezing or damaging the connector. After closing, the top cover 33 applies uniform downward pressure to the middle layer gasket 32, so that the silicone in the base 31, the filling groove 311, the flexible electrode, the middle layer gasket 32, and the top cover 33 are tightly attached, avoiding gaps between the layers, preventing silicone displacement and overflow, and ensuring that the double-sided silicone coating layer 2 is formed neatly.

[0061] Finally, the lower silicone in the filling groove 311 and the upper silicone in the filling window 322 are completely cured and shaped. After the silicone has cured, the top cover 33 and the middle gasket 32 ​​are removed in sequence, and then the coated flexible electrode is steadily taken out from the filling groove 311 of the base 31, thus completing the double-sided silicone coating structure reinforcement processing of the entire flexible electrode.

[0062] When the silicone is filled only in the filling groove 311 at the position corresponding to the flexible connection line area 12, the following can be obtained: Figure 12 The image shows a flexible electrode with a silicone coating layer 2. When the silicone filler 311, the silicone can coat the lower surfaces of the electrode array region 11, the flexible connection line region 12, and the electrode connection region 13 of the flexible electrode, resulting in the following: Figure 13 The flexible electrode shown has a silicone coating layer 2.

[0063] In this embodiment, a step-by-step silicone filling and precise alignment process design, relying on the silicone coating device's tank, filling window 322, and avoidance window structure, achieves controllable silicone coating on both sides of the flexible electrode. The resulting double-sided silicone coating layer 2 has uniform thickness, regular contour, and tight adhesion to the electrode surface. This comprehensively enhances the mechanical strength of the flexible electrode, strengthening its tensile and bending resistance and preventing damage and breakage of the film substrate under stress. Furthermore, the constraint effect of the double-sided silicone strengthens the interfacial bonding between the conductive layer and the flexible substrate, effectively suppressing interfacial delamination, microcracks, and peeling caused by cyclic deformation, preventing abnormal resistance or open-circuit failure. Simultaneously, the double-sided sealed coating forms a complete protective barrier, effectively preventing the infiltration of moist bodily fluids in the implantation environment, resisting electrochemical corrosion, and significantly improving the long-term operational stability and service reliability of the flexible electrode. In addition, the entire process is well-organized, easy to operate, and has good molding consistency, adapting to standardized and large-scale processing requirements.

[0064] Example 5 In Examples 2, 3, and 4, the silicone filling method can be manual application, semi-automatic application, or fully automatic application. Manual application involves manually injecting the silicone using a standard syringe. Semi-automatic application uses a syringe and injection pump, where the pump controls the amount and speed of silicone injected each time. Fully automatic application uses a fully automatic application machine for automatic positioning, displacement, and silicone injection.

[0065] Silicone curing can be achieved through three methods: room temperature curing, heated curing, and UV curing. Room temperature curing involves the silicone curing naturally at room temperature. Heated curing involves using a hot oven or other heating equipment to raise the temperature of the silicone, thus curing it. UV curing involves irradiating the silicone with an ultraviolet lamp (UV lamp).

[0066] Other embodiments of this application will readily conceive of by those skilled in the art upon consideration of the specification and practice of the embodiments thereof. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not claimed in this application. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of this application are indicated by the appended claims.

Claims

1. A silicone overmold device for flexible electrode structure enhancement, characterized by, include: The base has a filling groove for silicone coating on the lower side of the electrodes; The middle layer pad is provided with a first connector avoidance window and a silicone coating filling window on the upper side of the electrode. The first connector avoidance window is used to avoid the electrode connector area of ​​the flexible electrode to be coated. The top cover is provided with a second connector avoidance window corresponding to the first connector avoidance window. The second connector avoidance window is used to avoid the electrode connector area. The top cover is detachably connected to the base. The filling groove and the filling window cooperate with each other to define the position, outline and thickness of the silicone coating area. The coating area is one side or both sides of the flexible electrode to be coated. The middle layer pad is configured to be selectively placed or not placed between the base and the top cover. When the middle layer pad is not placed, the base and the top cover cooperate to cover the lower surface of the flexible electrode individually. When the middle layer pad is placed, the top cover is connected to the base and applies downward pressure to the middle layer pad, and closes the filling window, which in turn covers the flexible electrode on both sides or the upper surface on one side.

2. The silicone covering device of claim 1, wherein, There is a lateral filling gap between the filling groove and the area to be covered, and the lateral filling gap is used to accommodate the covering material covering the side of the area to be covered.

3. The silicone covering device of claim 1, wherein, The base is provided with multiple independent glue filling grooves, the middle layer gasket is provided with multiple independent silicone filling windows and multiple independent first connector avoidance windows, and the top cover is provided with multiple second connector avoidance windows, so as to realize the synchronous coating of multiple flexible electrodes to be coated.

4. The silicone covering device of claim 1, wherein, The base, the middle gasket, and the top cover are aligned and assembled using a positioning structure.

5. The silicone coating device according to claim 4, characterized in that, The positioning structure includes positioning holes or positioning buckles.

6. A method for silicone coating to reinforce flexible electrode structures, characterized in that, The silicone coating apparatus according to any one of claims 1-5 includes the following steps: Place the flexible electrode to be coated into the glue filling groove of the base; Place the middle layer pad above the flexible electrode to be covered, so that the first connector avoids the opening of the flexible electrode to be covered and the filling window corresponds to the area to be covered on the upper side of the electrode. Fill the filling window with silicone to cover the area to be coated on the upper side of the electrode; Close the top cover and avoid the electrode connector through the second connector avoidance window; After the silicone has cured, disassemble the device and remove the coated flexible electrode.

7. A method for silicone coating to reinforce flexible electrode structures, characterized in that, The silicone coating apparatus according to any one of claims 1-5 includes the following steps: Fill the area to be covered on the lower side of the electrode with silicone in the filling groove of the base; Place the flexible electrode to be coated in the filling tank, so that the area to be coated is on the underside of the silicone coated electrode; Close the top cover and avoid the electrode connector through the second connector avoidance window; After the silicone has cured, disassemble the device and remove the coated flexible electrode.

8. The silicone coating method according to claim 7, characterized in that, The flexible electrode to be coated includes an electrode array region, a flexible connection line region, and an electrode connection region. The area to be coated on the lower side of the electrode includes at least the lower surface of one or more of the electrode array region, the flexible connection line region, and the electrode connection region.

9. A method for silicone coating to reinforce flexible electrode structures, characterized in that, The silicone coating apparatus according to any one of claims 1-5 includes the following steps: Fill the area to be covered on the lower side of the electrode with silicone in the filling groove of the base; Place the flexible electrode to be coated in the filling tank, so that the area to be coated is on the underside of the silicone coated electrode; After the silicone in the area to be coated on the lower side of the electrode has cured, place the middle layer pad above the flexible electrode to be coated, so that the first connector avoids the opening and avoids the electrode connector, and the silicone filling window corresponds to the area to be coated on the upper side of the electrode. Fill the silicone filling window with silicone to cover the area to be coated on the upper side of the electrode; Close the top cover so that the second connector avoids the opening and avoids the electrode connector; After the silicone has cured, disassemble the device and remove the coated flexible electrode.

10. The silicone coating method according to claim 9, characterized in that, The flexible electrode to be coated includes an electrode array region, a flexible connection line region, and an electrode connection region. The area to be coated on the lower side of the electrode includes at least the lower surface of one or more of the electrode array region, the flexible connection line region, and the electrode connection region. The area to be covered on the upper side of the electrode includes at least the upper surface of the flexible connection line area.

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