Flexible conformable ems cosmetic device contact head structure manufacturing method and apparatus

Abstract

This application discloses a method and equipment for manufacturing a flexible, adhesive EMS beauty device contact head structure. The method involves removing surface oil, dust, and impurities from the substrate corresponding to the contact head using ultrasonic cleaning, followed by surface activation treatment of the substrate in a plasma treatment device with oxygen introduced to improve hydrophilicity and subsequent paste adhesion. The substrate is 2.5D sapphire glass. A screen printing plate is designed according to the functional requirements of the EMS electrodes. The screen printing plate is fixed on a curved surface printing device with the curved side of the glass substrate facing upwards and aligned with the pattern on the printing plate. A doctor blade is used to evenly scrape conductive paste across the pattern area of ​​the printing plate, printing the conductive paste onto the curved surface of the substrate to form an electrode pattern flush with the substrate surface. A silicon dioxide passivation layer is deposited on the surface of the conductive electrode using plasma-enhanced chemical vapor deposition. After deposition, the surface of the silicon dioxide passivation layer is mechanically polished to make the surface of the silicon dioxide passivation layer flush with the surface of the conductive electrode.

Description

Technical Field

[0001] This application relates to the field of beauty device manufacturing technology, and in particular to a method and equipment for manufacturing a flexible, fitting EMS beauty device contact head structure. Background Technology

[0002] In the field of beauty devices, especially EMS (electromuscular stimulation) devices, the conductivity, fit, and surface smoothness of the contact head structure directly affect current conduction efficiency and user experience. Existing technologies and traditional contact head manufacturing methods suffer from the following technical bottlenecks:

[0003] 1. Limitations of substrate materials: Commonly used glass or plastic substrates are not hard enough and are prone to wear after long-term use. In addition, the edge transition is not natural when the curved surface is bonded, resulting in uneven contact between the electrode and the skin.

[0004] 2. Challenges in printing curved electrodes: Traditional screen printing processes struggle to create uniform and flush electrode patterns on 2.5D curved substrates. Paste accumulation or thickness deviations are prone to occur at the electrode edges, affecting the uniformity of current distribution.

[0005] 3. Insufficient electrode adhesion and reliability: The bonding force between the conductive paste and the substrate is weak, and gaps or peeling are easily generated after high-temperature treatment. In addition, the passivation layer deposition process is difficult to precisely control the coverage of non-conductive areas and the exposure of conductive areas. Poor surface flatness leads to unstable contact impedance.

[0006] 4. Process compatibility defects: Existing methods have not optimized the matching process for the high hardness characteristics of sapphire glass. For example, the curved surface printing equipment and printing plate design lack adaptation to the curvature of the substrate, resulting in misalignment between the electrode pattern and the substrate contour, which affects the product yield.

[0007] Therefore, a method is urgently needed to solve at least one of the above problems. Summary of the Invention

[0008] This application provides a method and equipment for manufacturing a flexible, fitting contact head structure for a beauty device, aiming to solve the problem that in the field of beauty devices, especially in EMS (electromuscular stimulation) beauty devices, the conductivity, fit, and surface flatness of the contact head structure directly affect the current conduction efficiency and user experience.

[0009] In a first aspect, embodiments of this application provide a method for manufacturing a flexible, fitted EMS beauty device contact head structure, the method comprising:

[0010] The oil, dust, and impurities on the substrate surface corresponding to the contact head are removed by ultrasonic cleaning. Then, the contact head substrate is placed in a plasma treatment device and oxygen is introduced for surface activation treatment to improve hydrophilicity and subsequent slurry adhesion. The substrate is 2.5D sapphire glass.

[0011] A screen printing plate is designed according to the functional requirements of EMS electrodes. The pattern of the screen printing plate includes the electrode body and a chamfered transition area adapted to the contour of the 2.5D sapphire glass curved surface. A conductive paste is prepared by mixing silver powder, carbon nanotubes, organic binder and solvent.

[0012] The screen printing plate is fixed on the curved surface printing equipment, with the curved side of the 2.5D sapphire glass substrate facing upward and aligned with the pattern of the printing plate. The conductive paste is evenly scraped across the pattern area of ​​the printing plate using a doctor blade, so that the conductive paste is printed onto the surface of the substrate to form an electrode pattern flush with the surface of the substrate. The electrode pattern includes an electrode body and a chamfered transition area.

[0013] The substrate with the printed electrode pattern is placed in a high-temperature sintering furnace. First, the temperature is raised from room temperature to 400°C and held for 30 minutes to remove the organic carrier of the slurry. Then, the temperature is raised to 800-1200°C and held for 60 minutes to allow the silver powder and carbon nanotubes to fuse and solidify to form a strong conductive electrode with no processing gap between the electrode and the substrate.

[0014] A silicon dioxide passivation layer is deposited on the surface of a conductive electrode using plasma-enhanced chemical vapor deposition. The silicon dioxide passivation layer covers the non-conductive area of ​​the electrode and exposes the conductive contact area. After deposition, the surface of the silicon dioxide passivation layer is mechanically polished to make the surface of the silicon dioxide passivation layer flush with the surface of the conductive electrode.

[0015] In some embodiments, the removal of oil, dust and impurities from the substrate surface by ultrasonic cleaning includes: immersing the contact head substrate in a cleaning solution composed of ethanol and deionized water in a volume ratio of 1:1, ultrasonically treating it in an ultrasonic cleaner at a frequency of 40 to 60 kHz and a cleaning solution temperature of 40 to 55 degrees Celsius for 10 to 20 minutes, followed by three spray rinsings with deionized water, and then drying it by nitrogen purging for 5 to 8 minutes.

[0016] In some embodiments, the step of placing the contact head substrate in a plasma treatment device and introducing oxygen for surface activation treatment to improve hydrophilicity and subsequent slurry adhesion includes: placing the substrate in a plasma treatment chamber, evacuating the chamber to a pressure below 10 Pa, introducing oxygen at a flow rate of 50 to 100 standard cubic centimeters per minute, and activating the substrate for 5 to 15 minutes at a radio frequency power of 100 to 300 watts and a treatment temperature of 25 to 60 degrees Celsius, thereby reducing the contact angle of the substrate surface to below 30 degrees.

[0017] In some embodiments, the design of the screen printing plate according to the functional requirements of the EMS electrode includes: based on the current conduction path and electric field distribution requirements of the target electrode, using computer-aided design software to draw the graphic dimensions of the electrode body, so that the line width of the electrode body is 50 to 200 micrometers and the line spacing is 100 to 300 micrometers; at the same time, based on the radius of curvature of the 2.5D sapphire glass substrate surface, designing the arc radius of the chamfer transition area to be 0.8 to 1.2 times the radius of curvature of the substrate surface; and forming a hollow mesh with a pattern accuracy of ±5 micrometers on the stainless steel screen using laser engraving technology.

[0018] In some embodiments, the preparation of the conductive paste, which is a mixture of silver powder, carbon nanotubes, organic binder and solvent, includes: weighing 60 to 80% silver powder, 1 to 5% carbon nanotubes, 10 to 20% organic binder and 5 to 15% solvent by mass percentage; first, dry mixing the silver powder and carbon nanotubes in a three-dimensional mixer at a speed of 200 rpm for 30 minutes; then, adding the organic binder and solvent; and wet mixing in a water bath at 50 to 70 degrees Celsius at a speed of 500 rpm for 2 to 4 hours until the paste viscosity reaches 100 to 300 Pa·s.

[0019] In some embodiments, fixing the screen printing plate to the curved surface printing equipment, with the curved side of the 2.5D sapphire glass substrate facing upward and aligned with the printing plate pattern, includes: fixing the screen printing plate to the lifting platform of the curved surface printing equipment using a vacuum adsorption device, acquiring the contour image of the substrate surface using a vision alignment system, adjusting the substrate position by driving the platform with a servo motor, so that the deviation between the center of the electrode main pattern on the printing plate and the geometric center of the substrate does not exceed 50 micrometers, and the overlap between the chamfer transition area pattern and the edge of the substrate surface is not less than a preset overlap.

[0020] In some embodiments, the step of uniformly scraping conductive paste across the pattern area of ​​the printing plate with a doctor blade to print the conductive paste onto the curved surface of the substrate to form an electrode pattern flush with the substrate surface includes: mounting the doctor blade to the robotic arm of the printing equipment, adjusting the angle between the doctor blade and the printing plate to 45 to 60 degrees, scraping back and forth along the pattern area of ​​the printing plate 1 to 3 times with a pressure of 10 to 30 Newtons and a speed of 50 to 100 millimeters per second, monitoring the scraping pressure in real time with a pressure sensor, so that the uniformity error of the printed paste thickness is controlled within a preset error range, and the height difference between the paste surface and the curved surface of the substrate does not exceed a preset height difference.

[0021] In some embodiments, the deposition of a silicon dioxide passivation layer on the surface of a conductive electrode using plasma-enhanced chemical vapor deposition includes: placing the printed and sintered substrate into the reaction chamber of a PECVD equipment, introducing silane gas at a flow rate of 50 to 200 standard cubic centimeters per minute and oxygen at a flow rate of 100 to 300 standard cubic centimeters per minute, reacting for 30 to 120 minutes under the conditions of a deposition temperature of 200 to 400 degrees Celsius, a chamber pressure of 10 to 100 Pa, and a radio frequency power of 100 to 500 watts, controlling the thickness of the silicon dioxide layer to be 1 to 3 micrometers using a thickness monitoring device, so that the passivation layer completely covers the non-conductive area of ​​the electrode, and the deviation of the exposed area of ​​the conductive contact area from the design value does not exceed a preset deviation.

[0022] In some embodiments, the surface of the silica passivation layer is mechanically polished after deposition to make the surface of the silica passivation layer include: fixing the substrate to a carrier of a chemical mechanical polishing device, using a silica abrasive slurry with a particle size of 50 to 100 nanometers, polishing for 5 to 15 minutes under the conditions of polishing pressure of 5 to 20 kPa, carrier rotation speed of 50 to 150 rpm and polishing pad rotation speed of 100 to 200 rpm, and monitoring the surface flatness in real time through an online optical detection system, so that the height difference between the passivation layer surface and the electrode surface is less than 100 nanometers and the surface roughness Ra value does not exceed 0.2 micrometers.

[0023] Secondly, embodiments of this application provide a computer device for implementing the methods provided in any embodiment of this application.

[0024] The method provided in this application uses a 2.5D sapphire glass substrate, leveraging its high hardness (Mohs hardness 9), high light transmittance, and chemical stability to ensure that the contact head is not easily worn during long-term use. Furthermore, the curved contour conforms to the skin's curves, improving user comfort. Through a screen printing plate design adapted to the substrate's curved surface (including a chamfered transition area) and curved surface printing process, the conductive paste accurately covers the curved surface and is flush with the substrate surface. The electrode linewidth accuracy reaches ±5μm, and the thickness uniformity error is ≤±10%, solving the problem of paste accumulation at the edges in traditional processes. The problem of uneven thickness is addressed by a high-temperature sintering process (400℃ to remove organic carrier + 800-1200℃ silver-carbon fusion), which forms a chemical bond between the electrode and the substrate, eliminating processing gaps, increasing adhesion by more than 300%, and providing excellent bending resistance. The thickness of the silicon dioxide passivation layer deposited by PECVD is controllable (1-3μm), and mechanical polishing achieves flushness with the electrode surface (height difference <100nm, roughness Ra≤0.2μm), protecting non-conductive areas while ensuring stable impedance in conductive contact areas and improving current conduction efficiency.

[0025] 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

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

[0027] Figure 1 This is a schematic flowchart illustrating the steps of a method for manufacturing a flexible, adhesive EMS beauty device contact head structure according to an embodiment of this application;

[0028] Figure 2 This is a schematic diagram showing the disassembled contact head of a flexible EMS beauty device according to an embodiment of this application;

[0029] Figure 3 This is a schematic diagram of the structure of a beauty device provided in one embodiment of this application;

[0030] Figure 4 This is an exploded schematic diagram of a beauty device provided in one embodiment of this application;

[0031] Figure 5 This is a schematic block diagram of the structure of a computer device provided in an embodiment of this application.

[0032] 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. Detailed Implementation

[0033] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0034] The flowchart shown in the attached diagram is for illustrative purposes only and does not necessarily include all content and operations / steps, nor does it necessarily have to be performed in the order described. For example, some operations / steps can be broken down, combined, or partially merged, so the actual execution order may change depending on the actual situation.

[0035] It should be understood that, in order to clearly describe the technical solutions of the embodiments of the present invention, the terms "first" and "second" are used in the embodiments of the present invention to distinguish identical or similar items with essentially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and the terms "first" and "second" are not necessarily different.

[0036] It should be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0037] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0038] In the field of beauty devices, especially EMS (electromuscular stimulation) devices, the conductivity, fit, and surface smoothness of the contact head structure directly affect current conduction efficiency and user experience. Existing technologies and traditional contact head manufacturing methods suffer from the following technical bottlenecks:

[0039] 1. Limitations of substrate materials: Commonly used glass or plastic substrates are not hard enough and are prone to wear after long-term use. In addition, the edge transition is not natural when the curved surface is bonded, resulting in uneven contact between the electrode and the skin.

[0040] 2. Challenges in printing curved electrodes: Traditional screen printing processes struggle to create uniform and flush electrode patterns on 2.5D curved substrates. Paste accumulation or thickness deviations are prone to occur at the electrode edges, affecting the uniformity of current distribution.

[0041] 3. Insufficient electrode adhesion and reliability: The bonding force between the conductive paste and the substrate is weak, and gaps or peeling are easily generated after high-temperature treatment. In addition, the passivation layer deposition process is difficult to precisely control the coverage of non-conductive areas and the exposure of conductive areas. Poor surface flatness leads to unstable contact impedance.

[0042] 4. Process compatibility defects: Existing methods have not optimized the matching process for the high hardness characteristics of sapphire glass. For example, the curved surface printing equipment and printing plate design lack adaptation to the curvature of the substrate, resulting in misalignment between the electrode pattern and the substrate contour, which affects the product yield.

[0043] Therefore, a method is urgently needed to solve at least one of the above problems.

[0044] To solve the above problem, please refer to Figure 1This application provides a method for manufacturing a flexible, adhesive EMS beauty device contact head structure. This method is applied to the manufacture of devices such as… Figures 2 to 4 The contact head structure shown.

[0045] For example, such as Figures 2 to 4 As shown, the beauty device includes a contact head structure 100 and a main body 200. Specifically, it includes an upper cover 1, a first strong magnet 2, an inner liner of the upper cover 3, an upper shell of the head 4, sapphire glass 5, an EMS electrode 6, an EMS motherboard 7, a second strong magnet 8, an LED indicator board 9, a head liner 10, a lower shell of the main body 11, a base shell 12, a silicone pad 13, a main shell 14, a data cable interface cover 15 (such as a Type-C cover), a power button 16, a gear selector button 17, a lower shell of the head 18, a battery 19, a motherboard PCB 20, an upper shell of the main body 21, and a snap-fit ​​structure 22.

[0046] Specifically, such as Figure 1 As shown, the manufacturing method of the contact head structure of the provided flexible EMS beauty device includes steps S101 to S105. Details are as follows:

[0047] Step S101. Remove oil, dust and impurities from the substrate surface of the contact head by ultrasonic cleaning, and then place the contact head substrate in a plasma treatment device and introduce oxygen for surface activation treatment to improve hydrophilicity and subsequent slurry adhesion; the substrate is 2.5D sapphire glass.

[0048] Specifically, the core of this step lies in providing a clean, highly active substrate surface with excellent physicochemical properties for electrode fabrication. It solves the problems of insufficient hardness, easy wear, and poor adhesion caused by low surface energy of traditional substrate materials (such as ordinary glass or plastic).

[0049] 2.5D sapphire glass is selected as the substrate. Sapphire glass has extremely high hardness (Mohs hardness of 9, second only to diamond), significantly superior to traditional materials, thus solving the bottleneck of easy wear and tear over long-term use and ensuring the product's durability. Its 2.5D curved surface design can better conform to the contours of the human face, laying the physical foundation for achieving uniform current conduction.

[0050] Using an ultrasonic cleaner and a specialized neutral or weakly alkaline cleaning agent, the sapphire glass substrate is cleaned with high-frequency vibration. This process effectively removes microscopic oil stains, fingerprints, dust, and other organic and inorganic impurities adhering to the substrate surface, providing an absolutely clean starting point for subsequent processes.

[0051] The cleaned and dried substrate is placed in the working chamber of the plasma processing equipment. High-purity oxygen is introduced into the chamber as process gas, generating oxygen plasma under specific power, pressure, and time parameters. This highly active plasma bombards the substrate surface, further decomposing any residual organic contaminants and introducing polar groups such as hydroxyl (-OH) groups onto the sapphire glass surface, significantly increasing its surface energy (i.e., hydrophilicity). This activated surface exhibits better wettability with the conductive paste, creating a crucial prerequisite for a strong bond between the paste and the substrate.

[0052] Step S102. Design a screen printing plate according to the functional requirements of the EMS electrode. The pattern of the screen printing plate includes the electrode body and a chamfered transition area adapted to the contour of the 2.5D sapphire glass curved surface; prepare a conductive paste made of silver powder, carbon nanotubes, organic binder and solvent.

[0053] Specifically, this step aims to prepare customized tools and materials for curved surface printing, directly addressing the challenges of "curved surface electrode printing" and "insufficient electrode adhesion and reliability." It ensures that the electrode pattern can be accurately and completely transferred onto complex 2.5D curved surfaces.

[0054] A dedicated screen printing plate was designed based on the current distribution and functions required by the EMS beauty device. Its pattern not only includes the electrode body responsible for the main current conduction but also features a specially designed chamfered transition area. The shape and curvature of this transition area were precisely calculated to perfectly match the curved contour of the 2.5D sapphire glass substrate. This design ensures that during printing, the ink can smoothly and continuously cover the entire area from the center plane to the edge of the curved surface, avoiding problems such as pattern misalignment, ink buildup at the edges, or missing ink caused by mismatch between the printing plate and the substrate in traditional processes.

[0055] A high-performance composite conductive paste was prepared. Micron- or nano-sized silver powder was used as the main conductive medium to ensure low resistance and high conductivity. Carbon nanotubes were incorporated, utilizing their high aspect ratio and excellent conductivity to form a three-dimensional conductive network between the silver particles, enhancing the mechanical flexibility of the electrode and the uniformity of current distribution. Organic binders (such as epoxy resin and glass powder) provided the paste with film-forming properties and initial adhesion to the substrate. Solvents (such as terpineol and butyl carbitol) were used to adjust the viscosity and rheological properties of the paste, making it suitable for curved surface printing processes. This composite paste formulation aims to improve the density, adhesion, and conductive stability of the electrode after sintering.

[0056] Step S103. Fix the screen printing plate to the curved surface printing equipment, so that the curved side of the 2.5D sapphire glass substrate faces upward and is aligned with the pattern of the printing plate. Use a squeegee to evenly scrape the conductive paste across the pattern area of ​​the printing plate, so that the conductive paste is printed onto the surface of the substrate to form an electrode pattern flush with the surface of the substrate. The electrode pattern includes an electrode body and a chamfered transition area.

[0057] Specifically, this step is the core operation for forming the electrode pattern. Through specialized curved surface printing equipment and optimized process parameters, it is ensured that the electrode pattern with uniform thickness, clear edges, and flush with the substrate surface is formed on the 2.5D curved surface.

[0058] Using equipment specifically designed for curved surface printing, the customized screen printing plate from step S102 is precisely fixed. Then, the pre-treated 2.5D sapphire glass substrate is placed on the support platform with its curved side facing upwards. A high-precision optical positioning or mechanical clamping system is used to achieve micron-level precision alignment between the substrate's curved contour and the pattern on the printing plate (especially the chamfered transition area). This resolves the "electrode pattern misalignment with substrate contour" problem mentioned in the process compatibility defects.

[0059] Using a doctor blade optimized for hardness, angle, and pressure, the prepared conductive paste is scraped across a screen printing plate at a constant speed and pressure. Under the action of the doctor blade, the paste is precisely extruded through the mesh of the printing plate onto the curved surface of the substrate. Due to the perfect fit between the printing plate pattern and the substrate surface, and the suitable rheological properties of the paste, the paste can spread evenly, forming an electrode pattern of uniform thickness that is flush with the substrate surface. This "flush" structure avoids paste accumulation at the edges, greatly improves the uniformity of current distribution, and lays the foundation for the subsequent deposition of a smooth passivation layer.

[0060] Step S104. Place the substrate with the printed electrode pattern into a high-temperature sintering furnace. First, raise the temperature from room temperature to 400°C and hold for 30 minutes to remove the organic carrier of the slurry. Then raise the temperature to 800-1200°C and hold for 60 minutes to allow the silver powder and carbon nanotubes to fuse and solidify to form a strong conductive electrode with no processing gaps between the electrode and the substrate.

[0061] Specifically, this step transforms the printed paste layer into a dense, robust, and highly conductive solid electrode through a precisely controlled heat treatment process, and eliminates the interfacial gaps between the electrode and the substrate.

[0062] The printed substrate is then carefully placed into a temperature-controlled high-temperature sintering furnace. The sintering process consists of two key stages:

[0063] First, the temperature is raised from room temperature to approximately 400°C at a slow rate and held at this temperature for 30 minutes. The main purpose of this stage is to allow the organic carriers such as organic binders and solvents in the slurry to decompose and vaporize slowly and completely, so as to avoid the formation of bubbles, cracks or peeling of the electrode layer due to rapid volatilization.

[0064] Subsequently, the furnace temperature is raised to a high range of 800-1200℃ and held for 60 minutes. At this high temperature, the silver powder particles melt and diffuse, fusing with carbon nanotubes to form a continuous, dense three-dimensional conductive network structure. Simultaneously, inorganic binders such as glass powder that may be present in the slurry soften and undergo slight physicochemical reactions with the sapphire glass substrate surface, forming a strong metallurgical bond or mechanical intercalation.

[0065] After this high-temperature co-firing process, the resulting conductive electrode not only has extremely low resistance, but also achieves a firm, seamless bond with the sapphire substrate, completely solving the problem of "insufficient electrode adhesion and reliability" and ensuring the stability of the electrode during long-term use.

[0066] Step S105. A silicon dioxide passivation layer is deposited on the surface of the conductive electrode using plasma-enhanced chemical vapor deposition. The silicon dioxide passivation layer covers the non-conductive area of ​​the electrode and exposes the conductive contact area. After deposition, the surface of the silicon dioxide passivation layer is mechanically polished to make the surface of the silicon dioxide passivation layer flush with the surface of the conductive electrode.

[0067] Specifically, this step defines an effective conductive contact area by selectively covering the electrodes with an insulating layer and achieving a high degree of flatness on the overall surface, thus ensuring comfort during use and stability of current conduction.

[0068] A silicon dioxide passivation layer is deposited on the entire surface of the sintered device using plasma-enhanced chemical vapor deposition (PECVD). PECVD technology enables the deposition of high-quality thin films at relatively low temperatures. By using specialized masks or photolithography processes, the deposition area of ​​silicon dioxide can be precisely controlled, covering non-conductive areas of the electrodes where no current needs to pass through (such as gaps between electrodes and trace edges), while exposing conductive contact areas that need to be in contact with the skin.

[0069] After deposition, there may be a microscopic height difference between the silicon dioxide layer and the surface of the conductive electrode underneath. To obtain a perfectly smooth contact surface, a precise mechanical polishing process is used to treat the surface. Polishing precisely grinds away the protrusions, ultimately making the surface of the silicon dioxide passivation layer flush with the surface of the conductive contact area of ​​the conductive electrode.

[0070] This step solves the problem of unstable contact impedance caused by poor surface flatness. The flush structure ensures that the beauty device has uniform, stable and comfortable contact with the skin during use, avoiding "point contact" or current spikes caused by uneven surfaces. At the same time, the passivation layer effectively prevents current leakage and short circuit risks.

[0071] In some embodiments, the removal of oil, dust and impurities from the substrate surface by ultrasonic cleaning includes: immersing the contact head substrate in a cleaning solution composed of ethanol and deionized water in a volume ratio of 1:1, ultrasonically treating it in an ultrasonic cleaner at a frequency of 40 to 60 kHz and a cleaning solution temperature of 40 to 55 degrees Celsius for 10 to 20 minutes, followed by three spray rinsings with deionized water, and then drying it by nitrogen purging for 5 to 8 minutes.

[0072] This embodiment refines and optimizes the process parameters for the ultrasonic cleaning step in S101. It specifies the cleaning solution formulation, ultrasonic energy, temperature, and time, and introduces multi-stage cleaning and drying steps to achieve efficient, non-destructive, and thorough cleaning, providing an absolutely clean substrate surface for subsequent processes.

[0073] Analytical grade ethanol and high-purity deionized water are mixed in a 1:1 volume ratio to form a cleaning medium. Ethanol effectively dissolves organic oil stains, while deionized water washes away inorganic salts and dust particles.

[0074] Completely immerse the 2.5D sapphire glass substrate in the aforementioned cleaning solution. Start the ultrasonic cleaner, setting the frequency to between 40 and 60 kHz. This frequency provides sufficient cleaning force while avoiding potential damage to the precision substrate. Simultaneously, maintain the cleaning solution temperature between 40 and 55 degrees Celsius; appropriate heating helps improve the chemical activity and cleaning efficiency of the solution. Under these conditions, continue ultrasonic treatment for 10 to 20 minutes.

[0075] After ultrasonic treatment, the substrate is removed and rinsed three times with plenty of deionized water to thoroughly replace and remove any residual cleaning solution and removed contaminants. Immediately afterwards, high-purity nitrogen is used as an inert gas source to purge the substrate surface for 5 to 8 minutes, rapidly removing watermarks and achieving a residue-free and scratch-free drying process.

[0076] In some embodiments, the step of placing the contact head substrate in a plasma treatment device and introducing oxygen for surface activation treatment to improve hydrophilicity and subsequent slurry adhesion includes: placing the substrate in a plasma treatment chamber, evacuating the chamber to a pressure below 10 Pa, introducing oxygen at a flow rate of 50 to 100 standard cubic centimeters per minute, and activating the substrate for 5 to 15 minutes at a radio frequency power of 100 to 300 watts and a treatment temperature of 25 to 60 degrees Celsius, thereby reducing the contact angle of the substrate surface to below 30 degrees.

[0077] This embodiment refines the plasma activation process in step S101. By setting specific parameters for vacuum level, gas flow rate, power, temperature, and time, and proposing a quantified surface modification target (contact angle), the activation process is ensured to be controllable and repeatable, significantly improving the surface energy of the substrate and the adhesion of the slurry.

[0078] Place the cleaned and dried substrate into the chamber of the plasma processing equipment. Start the vacuum pump to evacuate the pressure inside the chamber to a vacuum environment below 10 Pa to eliminate air interference.

[0079] Oxygen is introduced into the chamber at a flow rate precisely controlled between 50 and 100 standard cubic centimeters per minute. The radio frequency power supply is then turned on, with the power set between 100 and 300 watts, and the chamber temperature maintained between 25 and 60 degrees Celsius. Under these conditions, treatment continues for 5 to 15 minutes. The oxygen plasma bombardment of the substrate surface effectively cleans and introduces polar groups.

[0080] After treatment, the water contact angle of the substrate surface was reduced to below 30 degrees by a contact angle meter. This quantitative indicator directly proves that the surface has changed from hydrophobic or weakly hydrophilic to strongly hydrophilic, which ensures good wetting and spreading of the slurry.

[0081] In some embodiments, the design of the screen printing plate according to the functional requirements of the EMS electrode includes: based on the current conduction path and electric field distribution requirements of the target electrode, using computer-aided design software to draw the graphic dimensions of the electrode body, so that the line width of the electrode body is 50 to 200 micrometers and the line spacing is 100 to 300 micrometers; at the same time, based on the radius of curvature of the 2.5D sapphire glass substrate surface, designing the arc radius of the chamfer transition area to be 0.8 to 1.2 times the radius of curvature of the substrate surface; and forming a hollow mesh with a pattern accuracy of ±5 micrometers on the stainless steel screen using laser engraving technology.

[0082] This embodiment details the design principles and manufacturing method of the screen printing plate in step S102. Based on electrical properties and substrate geometry, it provides specific design parameters for the electrode pattern (line width / spacing) and chamfered transition area, and specifies a high-precision plate-making process to ensure that the printing plate can perfectly adapt to the 2.5D curved substrate.

[0083] Computer-aided design software is used to design patterns based on the required current conduction paths and desired electric field distribution of the beauty device. The linewidth of the electrode body is designed to be 50 to 200 micrometers, and the line spacing is 100 to 300 micrometers to balance conductivity and safety. The radius of curvature of the chamfered transition area is determined based on the radius of curvature of the substrate surface, typically 0.8 to 1.2 times it, to achieve a smooth transition.

[0084] The designed pattern is transferred onto a stainless steel mesh using laser engraving. Laser engraving achieves extremely high precision, ensuring that the edge accuracy of the final perforated mesh is controlled within ±5 micrometers.

[0085] In some embodiments, the preparation of the conductive paste, which is a mixture of silver powder, carbon nanotubes, organic binder and solvent, includes: weighing 60 to 80% silver powder, 1 to 5% carbon nanotubes, 10 to 20% organic binder and 5 to 15% solvent by mass percentage; first, dry mixing the silver powder and carbon nanotubes in a three-dimensional mixer at a speed of 200 rpm for 30 minutes; then, adding the organic binder and solvent; and wet mixing in a water bath at 50 to 70 degrees Celsius at a speed of 500 rpm for 2 to 4 hours until the paste viscosity reaches 100 to 300 Pa·s.

[0086] This embodiment quantifies the composition and mixing process of the conductive paste in step S102. By using precise material proportioning and a staged mixing method (dry mixing followed by wet mixing), and controlling the final viscosity, the aim is to prepare a highly conductive paste that is uniformly dispersed, has stable performance, and is suitable for curved surface printing.

[0087] Weigh out 60 to 80% silver powder, 1 to 5% carbon nanotubes, 10 to 20% organic binder, and 5 to 15% solvent by weight percentage. First, put the silver powder and carbon nanotubes into a three-dimensional mixer and dry mix them at 200 rpm for 30 minutes to initially and uniformly mix the two conductive fillers.

[0088] Organic binders and solvents are added to the dry-mixed powder. The mixing container is then placed in a water bath at 50 to 70 degrees Celsius and wet-mixed at a higher speed of 500 rpm for 2 to 4 hours. This process ensures that all components are fully dispersed and blended. Finally, the viscosity of the paste is measured using a rheometer to achieve the ideal range of 100 to 300 Pa·s to meet printing requirements.

[0089] In some embodiments, fixing the screen printing plate to the curved surface printing equipment, with the curved side of the 2.5D sapphire glass substrate facing upward and aligned with the printing plate pattern, includes: fixing the screen printing plate to the lifting platform of the curved surface printing equipment using a vacuum adsorption device, acquiring the contour image of the substrate surface using a vision alignment system, adjusting the substrate position by driving the platform with a servo motor, so that the deviation between the center of the electrode main pattern on the printing plate and the geometric center of the substrate does not exceed 50 micrometers, and the overlap between the chamfer transition area pattern and the edge of the substrate surface is not less than a preset overlap.

[0090] This embodiment details the specific method for achieving precise alignment in step S103. It combines vacuum fixing, visual recognition, and servo control technologies, and sets strict alignment tolerances to solve the alignment problem between curved substrates and planar printing plate patterns.

[0091] The prepared screen printing plate is firmly fixed on the lifting platform of the printing equipment using a vacuum adsorption device.

[0092] Start the vision alignment system (which typically includes a high-resolution camera and image processing software) to acquire images of the contour of the base surface placed on the support platform.

[0093] The vision system compares the acquired image with the preset printing plate pattern and calculates the positional deviation. Then, a servo motor-driven platform is used for fine-tuning to ensure that the deviation between the center of the electrode main pattern on the printing plate and the geometric center of the substrate does not exceed 50 micrometers. At the same time, it ensures that the overlap between the chamfered transition area pattern and the edge of the substrate curved surface reaches a preset high standard (usually ≥95%).

[0094] In some embodiments, the step of uniformly scraping conductive paste across the pattern area of ​​the printing plate with a doctor blade to print the conductive paste onto the curved surface of the substrate to form an electrode pattern flush with the substrate surface includes: mounting the doctor blade to the robotic arm of the printing equipment, adjusting the angle between the doctor blade and the printing plate to 45 to 60 degrees, scraping back and forth along the pattern area of ​​the printing plate 1 to 3 times with a pressure of 10 to 30 Newtons and a speed of 50 to 100 millimeters per second, monitoring the scraping pressure in real time with a pressure sensor, so that the uniformity error of the printed paste thickness is controlled within a preset error range, and the height difference between the paste surface and the curved surface of the substrate does not exceed a preset height difference.

[0095] This embodiment clarifies the key process parameters of the squeegee operation in step S103. By controlling the squeegee angle, pressure, speed, and number of squeegees, and using sensors for real-time monitoring, the aim is to obtain an electrode pattern with uniform thickness and strictly flush with the substrate surface.

[0096] Mount the doctor blade onto the robotic arm and adjust its angle with the printing plate surface to 45 to 60 degrees, which is a classic angle range that ensures good ink transfer and doctoring effect.

[0097] Set the squeegee pressure to 10 to 30 Newtons and the speed to 50 to 100 millimeters per second, and control the robotic arm to drive the squeegee to squeegee back and forth along the pattern area 1 to 3 times.

[0098] An integrated pressure sensor monitors and maintains stable printing pressure in real time. This combination of parameters ensures that the uniformity of the printed paste thickness and the height difference between the paste surface and the substrate are controlled within a strict preset range, thus achieving the goal of "flush".

[0099] In some embodiments, the deposition of a silicon dioxide passivation layer on the surface of a conductive electrode using plasma-enhanced chemical vapor deposition includes: placing the printed and sintered substrate into the reaction chamber of a PECVD equipment, introducing silane gas at a flow rate of 50 to 200 standard cubic centimeters per minute and oxygen at a flow rate of 100 to 300 standard cubic centimeters per minute, reacting for 30 to 120 minutes under the conditions of a deposition temperature of 200 to 400 degrees Celsius, a chamber pressure of 10 to 100 Pa, and a radio frequency power of 100 to 500 watts, controlling the thickness of the silicon dioxide layer to be 1 to 3 micrometers using a thickness monitoring device, so that the passivation layer completely covers the non-conductive area of ​​the electrode, and the deviation of the exposed area of ​​the conductive contact area from the design value does not exceed a preset deviation.

[0100] This embodiment details the process conditions for depositing a silicon dioxide passivation layer using PECVD technology in step S105. It specifies a complete set of parameters, including reaction gas, flow rate, temperature, pressure, power, and time, and emphasizes precise control over the thickness and exposed area.

[0101] The sintered substrate is placed in the reaction chamber of a PECVD apparatus. Silane gas (flow rate 50-200 sccm) is introduced into the reaction chamber as the silicon source, and oxygen (flow rate 100-300 sccm) is introduced as the reaction gas. The deposition temperature is set to 200-400 degrees Celsius, the chamber pressure to 10-100 Pa, and 100-500 W of radio frequency power is applied to generate plasma. The reaction is carried out under these conditions for 30 to 120 minutes. The thickness of the generated silicon dioxide layer is monitored in real time using a thickness monitor (such as an elliptic transducer) and controlled to be between 1 and 3 micrometers. Masking techniques are used to ensure that the passivation layer completely covers the non-conductive areas of the electrodes, while the exposed area of ​​the conductive contact area deviates from the design value within a preset allowable range (e.g., ±5%).

[0102] In some embodiments, the surface of the silica passivation layer is mechanically polished after deposition to make the surface of the silica passivation layer include: fixing the substrate to a carrier of a chemical mechanical polishing device, using a silica abrasive slurry with a particle size of 50 to 100 nanometers, polishing for 5 to 15 minutes under the conditions of polishing pressure of 5 to 20 kPa, carrier rotation speed of 50 to 150 rpm and polishing pad rotation speed of 100 to 200 rpm, and monitoring the surface flatness in real time through an online optical detection system, so that the height difference between the passivation layer surface and the electrode surface is less than 100 nanometers and the surface roughness Ra value does not exceed 0.2 micrometers.

[0103] By combining chemical etching and mechanical polishing, and by controlling the polishing pressure, rotation speed, time, and the use of specific abrasives, a nanoscale ultra-smooth and flat surface can be achieved.

[0104] The substrate with the passivated layer deposited is fixed on a carrier of a chemical mechanical polishing (CMP) device. A silica suspension with a particle size of 50 to 100 nanometers is used as the abrasive slurry. The polishing pressure is set to 5 to 20 kPa, the carrier rotation speed to 50 to 150 rpm, and the polishing pad rotation speed to 100 to 200 rpm. Polishing is performed under these conditions for 5 to 15 minutes. The surface smoothness and roughness are monitored in real time using an online optical inspection system (such as a laser interferometer).

[0105] After polishing, the height difference between the passivation layer surface and the conductive electrode surface must be less than 100 nanometers, and the surface roughness Ra value must not exceed 0.2 micrometers. This ensures excellent fit and a stable current conduction interface when the contact head contacts the skin.

[0106] In some embodiments, machine vision is used to identify contamination levels and defects, and AI models are used to dynamically recommend or execute optimal process parameters for each substrate, achieving personalized and precise treatment for each substrate.

[0107] At the start of preprocessing, images of the substrate surface are first acquired using a high-resolution industrial camera.

[0108] Image data is input into a pre-trained deep learning convolutional neural network model. This model is able to identify and quantify the types of contaminants (such as oil stains and particles), their distribution, and defects such as micro-scratches on the substrate surface.

[0109] The AI ​​model dynamically adjusts the parameters for subsequent steps based on the diagnostic results:

[0110] If stubborn organic stains are detected, the AI ​​will instruct the ultrasonic cleaner to appropriately increase the cleaning fluid temperature (e.g., raise it to the upper limit of 55°C) and extend the cleaning time; if the substrate is relatively clean, it will use mild default parameters to save energy and time.

[0111] Based on the material batch and surface condition of the substrate, the AI ​​recommends the optimal plasma power and processing time to ensure that each substrate achieves and does not exceed the target hydrophilicity (contact angle <30°) and avoids overactivation that could damage the surface.

[0112] The system records the parameters and final quality inspection results for each process, forming a closed loop to continuously optimize the AI ​​decision-making model.

[0113] In some embodiments, this embodiment addresses the problem of parameter adjustment in curved surface printing being highly dependent on engineers' experience. It introduces a reinforcement learning algorithm, allowing the machine to autonomously learn, through continuous "trial and error-reward" processes, the optimal combination of process parameters for achieving the best printing effect (uniformity, flatness) on complex curved surfaces.

[0114] First, a digital twin model is created in the computer to simulate the curved surface printing equipment, the rheological behavior of the paste, and the morphology of the substrate.

[0115] The printing control system is treated as a reinforcement learning agent. Its "actions" are adjusting parameters such as squeegee angle, pressure, and speed; its "state" is the real-time acquisition of printed images and sensor data; and its "rewards" are based on quantitative indicators such as the uniformity of electrode thickness and edge sharpness after printing.

[0116] The agent begins printing randomly or based on default parameters in the initial stage. After printing, the print quality is evaluated by an online inspection system (such as a laser profilometer), and a "reward" is calculated based on the evaluation results. Through thousands of simulations and actual iterations, the agent learns a complex, non-linear strategy: for example, automatically increasing pressure slightly in areas of high curvature and adjusting the squeegee angle in edge areas to maximize the "reward." A well-trained agent can respond in real time to slight changes in the viscosity of different batches of ink, fluctuations in environmental temperature and humidity, and dynamically fine-tune parameters to always ensure the highest printing yield and consistency.

[0117] In some embodiments, the conventional sintering process, which uses a fixed temperature-time curve, cannot cope with material fluctuations and uneven thermal fields in the equipment. This embodiment utilizes a machine learning model to predict sintering results and adjusts the furnace environment in real time to ensure optimal and consistent electrode performance.

[0118] During the sintering process, in addition to temperature and time, the built-in fiber optic spectrometer or thermal imager is used to collect spectral / thermal radiation data of the furnace atmosphere and the product surface in real time.

[0119] This real-time data is fed into a machine learning regression model (such as a gradient boosting tree). After training, the model can predict key performance indicators such as sheet resistance and adhesion strength of the final electrode in real time based on the current operating conditions.

[0120] The predicted results are compared with the preset ideal value range. If the model predicts that the sheet resistance of the electrode after sintering may be too high under the current parameters, the system will automatically and slightly adjust the set temperature of the subsequent heat preservation stage or introduce an appropriate amount of protective gas through the model prediction control algorithm, so as to "guide" the sintering process towards the ideal result, thereby achieving "pre-emptive" control of sintering quality rather than "post-emptive" inspection.

[0121] In some embodiments, this embodiment uses laser processing to replace or assist the traditional PECVD deposition + mask process, combined with high-precision computer vision, to realize the digitalization and maskless "printing" of the passivation layer, and has the ability to repair in situ.

[0122] A high-precision computer vision system scans the sintered substrate to accurately identify the location and contour of each conductive contact area.

[0123] Option 1 (Deposition): Using a femtosecond laser of a specific wavelength, precisely focused on the non-conductive area requiring a passivation layer. The laser induces a chemical reaction in the precursor gas (such as silane and oxygen), depositing silicon dioxide only at the precise laser-irradiated locations. This is an "additive" approach. Option 2 (Removal): First, a uniform silicon dioxide film is deposited over the entire electrode. Then, a laser is used to precisely ablate the passivation layer above the conductive contact area, "drawing" the exposed pattern like a laser printer.

[0124] In Option 2, the surface is immediately scanned using a confocal microscope or atomic force microscope after laser ablation. If the AI ​​identifies a conductive area that is not fully exposed due to insufficient ablation, the system will instruct the laser to perform microsecond-level supplementary processing on that point, ensuring that the accuracy of the exposed area far exceeds that of traditional masking methods.

[0125] In some embodiments, this is achieved by constructing an intelligent hub that covers the entire manufacturing process. It creates a digital twin for each product, tracks all process data in real time, and is able to predict final quality and quickly diagnose the root causes of defects.

[0126] Throughout the manufacturing process, each substrate is assigned a unique ID, and comprehensive data (such as images, temperature, pressure, and spectrum) is collected in real time at each workstation. All data is then bound to the substrate's ID, and a complete digital twin is built in the cloud, recording its data "for its entire life."

[0127] Before the final electrical test, the system can use a deep neural network model to predict the final conductivity, adhesion and other properties of the substrate based on the digital twin data of the entire process.

[0128] If a substrate is ultimately found to be defective, the system can immediately retrieve its digital twin.

[0129] The AI ​​model analyzes abnormal data fluctuations throughout the production chain and identifies the most probable root cause. For example, the system might indicate: "This product has a high yield risk, and the root cause has an 85% probability of being caused by instantaneous fluctuations in the scratch-off pressure in the S103 stage." This significantly shortens the problem-solving cycle.

[0130] Please see Figure 5 , Figure 5 This is a schematic block diagram of the structure of a computer device provided in an embodiment of this application. The computer device includes a processor, a memory, and a network interface connected via a device bus, wherein the memory may include a storage medium and internal memory.

[0131] The storage medium can store operating devices and computer programs. The computer program includes program instructions that, when executed, cause the processor to perform any method for manufacturing the contact head structure of a flexible, adhesive EMS beauty device.

[0132] The processor provides computing and control capabilities, supporting the operation of the entire computer device.

[0133] The internal memory provides an environment for the execution of computer programs in non-volatile storage media. When the computer program is executed by the processor, it enables the processor to execute any method for manufacturing the contact head structure of a flexible EMS beauty device.

[0134] This network interface is used for network communication, such as sending assigned tasks. Those skilled in the art will understand that... Figure 5 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the terminal to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0135] It should be understood that the processor can be a Central Processing Unit (CPU), but it can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among these, a general-purpose processor can be a microprocessor or any conventional processor.

[0136] In one embodiment, the processor is configured to run a computer program stored in memory to perform the following steps:

[0137] The oil, dust, and impurities on the substrate surface corresponding to the contact head are removed by ultrasonic cleaning. Then, the contact head substrate is placed in a plasma treatment device and oxygen is introduced for surface activation treatment to improve hydrophilicity and subsequent slurry adhesion. The substrate is 2.5D sapphire glass.

[0138] A screen printing plate is designed according to the functional requirements of EMS electrodes. The pattern of the screen printing plate includes the electrode body and a chamfered transition area adapted to the contour of the 2.5D sapphire glass curved surface. A conductive paste is prepared by mixing silver powder, carbon nanotubes, organic binder and solvent.

[0139] The screen printing plate is fixed on the curved surface printing equipment, with the curved side of the 2.5D sapphire glass substrate facing upward and aligned with the pattern of the printing plate. The conductive paste is evenly scraped across the pattern area of ​​the printing plate using a doctor blade, so that the conductive paste is printed onto the surface of the substrate to form an electrode pattern flush with the surface of the substrate. The electrode pattern includes an electrode body and a chamfered transition area.

[0140] The substrate with the printed electrode pattern is placed in a high-temperature sintering furnace. First, the temperature is raised from room temperature to 400°C and held for 30 minutes to remove the organic carrier of the slurry. Then, the temperature is raised to 800-1200°C and held for 60 minutes to allow the silver powder and carbon nanotubes to fuse and solidify to form a strong conductive electrode with no processing gap between the electrode and the substrate.

[0141] A silicon dioxide passivation layer is deposited on the surface of a conductive electrode using plasma-enhanced chemical vapor deposition. The silicon dioxide passivation layer covers the non-conductive area of ​​the electrode and exposes the conductive contact area. After deposition, the surface of the silicon dioxide passivation layer is mechanically polished to make the surface of the silicon dioxide passivation layer flush with the surface of the conductive electrode.

[0142] In some embodiments, the removal of oil, dust and impurities from the substrate surface by ultrasonic cleaning includes: immersing the contact head substrate in a cleaning solution composed of ethanol and deionized water in a volume ratio of 1:1, ultrasonically treating it in an ultrasonic cleaner at a frequency of 40 to 60 kHz and a cleaning solution temperature of 40 to 55 degrees Celsius for 10 to 20 minutes, followed by three spray rinsings with deionized water, and then drying it by nitrogen purging for 5 to 8 minutes.

[0143] In some embodiments, the step of placing the contact head substrate in a plasma treatment device and introducing oxygen for surface activation treatment to improve hydrophilicity and subsequent slurry adhesion includes: placing the substrate in a plasma treatment chamber, evacuating the chamber to a pressure below 10 Pa, introducing oxygen at a flow rate of 50 to 100 standard cubic centimeters per minute, and activating the substrate for 5 to 15 minutes at a radio frequency power of 100 to 300 watts and a treatment temperature of 25 to 60 degrees Celsius, thereby reducing the contact angle of the substrate surface to below 30 degrees.

[0144] In some embodiments, the design of the screen printing plate according to the functional requirements of the EMS electrode includes: based on the current conduction path and electric field distribution requirements of the target electrode, using computer-aided design software to draw the graphic dimensions of the electrode body, so that the line width of the electrode body is 50 to 200 micrometers and the line spacing is 100 to 300 micrometers; at the same time, based on the radius of curvature of the 2.5D sapphire glass substrate surface, designing the arc radius of the chamfer transition area to be 0.8 to 1.2 times the radius of curvature of the substrate surface; and forming a hollow mesh with a pattern accuracy of ±5 micrometers on the stainless steel screen using laser engraving technology.

[0145] In some embodiments, the preparation of the conductive paste, which is a mixture of silver powder, carbon nanotubes, organic binder and solvent, includes: weighing 60 to 80% silver powder, 1 to 5% carbon nanotubes, 10 to 20% organic binder and 5 to 15% solvent by mass percentage; first, dry mixing the silver powder and carbon nanotubes in a three-dimensional mixer at a speed of 200 rpm for 30 minutes; then, adding the organic binder and solvent; and wet mixing in a water bath at 50 to 70 degrees Celsius at a speed of 500 rpm for 2 to 4 hours until the paste viscosity reaches 100 to 300 Pa·s.

[0146] In some embodiments, fixing the screen printing plate to the curved surface printing equipment, with the curved side of the 2.5D sapphire glass substrate facing upward and aligned with the printing plate pattern, includes: fixing the screen printing plate to the lifting platform of the curved surface printing equipment using a vacuum adsorption device, acquiring the contour image of the substrate surface using a vision alignment system, adjusting the substrate position by driving the platform with a servo motor, so that the deviation between the center of the electrode main pattern on the printing plate and the geometric center of the substrate does not exceed 50 micrometers, and the overlap between the chamfer transition area pattern and the edge of the substrate surface is not less than a preset overlap.

[0147] In some embodiments, the step of uniformly scraping conductive paste across the pattern area of ​​the printing plate with a doctor blade to print the conductive paste onto the curved surface of the substrate to form an electrode pattern flush with the substrate surface includes: mounting the doctor blade to the robotic arm of the printing equipment, adjusting the angle between the doctor blade and the printing plate to 45 to 60 degrees, scraping back and forth along the pattern area of ​​the printing plate 1 to 3 times with a pressure of 10 to 30 Newtons and a speed of 50 to 100 millimeters per second, monitoring the scraping pressure in real time with a pressure sensor, so that the uniformity error of the printed paste thickness is controlled within a preset error range, and the height difference between the paste surface and the curved surface of the substrate does not exceed a preset height difference.

[0148] In some embodiments, the deposition of a silicon dioxide passivation layer on the surface of a conductive electrode using plasma-enhanced chemical vapor deposition includes: placing the printed and sintered substrate into the reaction chamber of a PECVD equipment, introducing silane gas at a flow rate of 50 to 200 standard cubic centimeters per minute and oxygen at a flow rate of 100 to 300 standard cubic centimeters per minute, reacting for 30 to 120 minutes under the conditions of a deposition temperature of 200 to 400 degrees Celsius, a chamber pressure of 10 to 100 Pa, and a radio frequency power of 100 to 500 watts, controlling the thickness of the silicon dioxide layer to be 1 to 3 micrometers using a thickness monitoring device, so that the passivation layer completely covers the non-conductive area of ​​the electrode, and the deviation of the exposed area of ​​the conductive contact area from the design value does not exceed a preset deviation.

[0149] In some embodiments, the surface of the silica passivation layer is mechanically polished after deposition to make the surface of the silica passivation layer include: fixing the substrate to a carrier of a chemical mechanical polishing device, using a silica abrasive slurry with a particle size of 50 to 100 nanometers, polishing for 5 to 15 minutes under the conditions of polishing pressure of 5 to 20 kPa, carrier rotation speed of 50 to 150 rpm and polishing pad rotation speed of 100 to 200 rpm, and monitoring the surface flatness in real time through an online optical detection system, so that the height difference between the passivation layer surface and the electrode surface is less than 100 nanometers and the surface roughness Ra value does not exceed 0.2 micrometers.

[0150] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, causes the processor to perform the steps of the method for manufacturing a flexible-fitting EMS beauty device contact head structure as provided in any embodiment of this application.

[0151] The computer-readable storage medium may be an internal storage unit of the computer device described in the foregoing embodiments, such as the hard disk or memory of the computer device. The computer-readable storage medium may also be an external storage device of the computer device, such as a plug-in hard disk, SmartMedia Card (SMC), Secure Digital (SD) card, or Flash Card equipped on the computer device.

[0152] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for manufacturing a flexible, adhesive EMS beauty device contact head structure, characterized in that, The method includes: The oil, dust, and impurities on the substrate surface corresponding to the contact head are removed by ultrasonic cleaning. Then, the contact head substrate is placed in a plasma treatment device and oxygen is introduced for surface activation treatment to improve hydrophilicity and subsequent slurry adhesion. The substrate is 2.5D sapphire glass. A screen printing plate is designed according to the functional requirements of EMS electrodes. The pattern of the screen printing plate includes the electrode body and a chamfered transition area adapted to the contour of the 2.5D sapphire glass curved surface. A conductive paste is prepared by mixing silver powder, carbon nanotubes, organic binder and solvent. The screen printing plate is fixed on the curved surface printing equipment, with the curved side of the 2.5D sapphire glass substrate facing upward and aligned with the pattern of the printing plate. The conductive paste is evenly scraped across the pattern area of ​​the printing plate using a doctor blade, so that the conductive paste is printed onto the surface of the substrate to form an electrode pattern flush with the surface of the substrate. The electrode pattern includes an electrode body and a chamfered transition area. The substrate with the printed electrode pattern is placed in a high-temperature sintering furnace. First, the temperature is raised from room temperature to 400°C and held for 30 minutes to remove the organic carrier of the slurry. Then, the temperature is raised to 800-1200°C and held for 60 minutes to allow the silver powder and carbon nanotubes to fuse and solidify to form a strong conductive electrode with no processing gap between the electrode and the substrate. A silicon dioxide passivation layer is deposited on the surface of a conductive electrode using plasma-enhanced chemical vapor deposition. The silicon dioxide passivation layer covers the non-conductive area of ​​the electrode and exposes the conductive contact area. After deposition, the surface of the silicon dioxide passivation layer is mechanically polished to make the surface of the silicon dioxide passivation layer flush with the surface of the conductive electrode.

2. The method according to claim 1, characterized in that, The process of removing oil, dust, and impurities from the substrate surface using ultrasonic cleaning includes: The contact head substrate is immersed in a cleaning solution made of ethanol and deionized water in a 1:1 volume ratio and ultrasonically treated in an ultrasonic cleaner at a frequency of 40 to 60 kHz and a cleaning solution temperature of 40 to 55 degrees Celsius for 10 to 20 minutes. Then it is rinsed three times with deionized water and dried by nitrogen purging for 5 to 8 minutes.

3. The method according to claim 1, characterized in that, The step of placing the contact head substrate in a plasma treatment device and introducing oxygen for surface activation treatment to improve hydrophilicity and subsequent slurry adhesion includes: The substrate is placed in a plasma processing chamber, evacuated until the chamber pressure is below 10 Pa, and oxygen is introduced at a flow rate of 50 to 100 standard cubic centimeters per minute. The substrate is then activated for 5 to 15 minutes at a radio frequency power of 100 to 300 watts and a processing temperature of 25 to 60 degrees Celsius, thereby reducing the contact angle of the substrate surface to below 30 degrees.

4. The method according to claim 1, characterized in that, The design of the screen printing plate according to the functional requirements of EMS electrodes includes: Based on the current conduction path and electric field distribution requirements of the target electrode, computer-aided design software is used to draw the graphic dimensions of the electrode body, so that the line width of the electrode body is 50 to 200 micrometers and the line spacing is 100 to 300 micrometers. At the same time, according to the curvature radius of the 2.5D sapphire glass substrate, the radius of the chamfered transition area is designed to be 0.8 to 1.2 times the radius of the substrate surface. The pattern is formed on the stainless steel mesh with a pattern accuracy of ±5 micrometers by laser engraving process.

5. The method according to claim 1, characterized in that, The preparation of the conductive paste, which is a mixture of silver powder, carbon nanotubes, organic binder, and solvent, includes: Weigh out 60 to 80% silver powder, 1 to 5% carbon nanotubes, 10 to 20% organic binder, and 5 to 15% solvent by mass percentage. First, dry mix the silver powder and carbon nanotubes in a three-dimensional mixer at 200 rpm for 30 minutes. Then, add the organic binder and solvent and wet mix in a water bath at 50 to 70 degrees Celsius at 500 rpm for 2 to 4 hours until the slurry viscosity reaches 100 to 300 Pa·s.

6. The method according to claim 1, characterized in that, The step of fixing the screen printing plate to the curved surface printing equipment, with the curved side of the 2.5D sapphire glass substrate facing upwards and aligned with the printing plate pattern, includes: The screen printing plate is fixed to the lifting platform of the curved surface printing equipment by a vacuum adsorption device. The contour image of the substrate curved surface is acquired by a vision alignment system. The position of the substrate is adjusted by a servo motor driving the platform so that the deviation between the center of the electrode main pattern on the printing plate and the geometric center of the substrate does not exceed 50 micrometers, and the overlap between the chamfer transition area pattern and the edge of the substrate curved surface is not lower than the preset overlap.

7. The method according to claim 1, characterized in that, The process of uniformly scraping conductive paste across the patterned area of ​​the printing plate using a doctor blade, thereby printing the conductive paste onto the curved surface of the substrate to form an electrode pattern flush with the substrate surface, includes: The doctor blade is installed on the robotic arm of the printing equipment. The angle between the doctor blade and the printing plate is adjusted to 45 to 60 degrees. The doctor blade is scraped back and forth 1 to 3 times along the pattern area of ​​the printing plate at a pressure of 10 to 30 Newtons and a speed of 50 to 100 millimeters per second. The scraping pressure is monitored in real time by a pressure sensor to control the uniformity error of the printed paste thickness within the preset error range, and the height difference between the paste surface and the substrate surface does not exceed the preset height difference.

8. The method according to claim 1, characterized in that, The deposition of a silicon dioxide passivation layer on the surface of a conductive electrode using plasma-enhanced chemical vapor deposition includes: The printed and sintered substrate is placed in the reaction chamber of the PECVD equipment, and silane gas and oxygen at a flow rate of 50 to 200 standard cubic centimeters per minute and 100 to 300 standard cubic centimeters per minute are introduced. The reaction is carried out for 30 to 120 minutes under the conditions of deposition temperature of 200 to 400 degrees Celsius, chamber pressure of 10 to 100 Pa and radio frequency power of 100 to 500 watts. The thickness of the silicon dioxide layer is controlled to be 1 to 3 micrometers by a thickness monitoring instrument, so that the passivation layer completely covers the non-conductive area of ​​the electrode, and the deviation of the exposed area of ​​the conductive contact area from the design value does not exceed the preset deviation.

9. The method according to claim 1, characterized in that, The surface of the silicon dioxide passivation layer is mechanically polished after deposition, so that the surface of the silicon dioxide passivation layer includes: The substrate is fixed on the carrier of a chemical mechanical polishing (CMP) device. A silica abrasive slurry with a particle size of 50 to 100 nanometers is used. Polishing is carried out for 5 to 15 minutes under the conditions of polishing pressure of 5 to 20 kPa, carrier rotation speed of 50 to 150 rpm and polishing pad rotation speed of 100 to 200 rpm. The surface flatness is monitored in real time by an online optical detection system to ensure that the height difference between the passivation layer surface and the electrode surface is less than 100 nanometers and the surface roughness Ra value does not exceed 0.2 micrometers.

10. A computer device, characterized in that, The computer device includes a memory and a processor; The memory is used to store computer programs; The processor is configured to execute the computer program and, in executing the computer program, implement the method as described in any one of claims 1 to 9.

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