An electro-isolated flexible integrated physiological signal detection patch and a preparation method thereof

Abstract

This invention relates to the interdisciplinary field of sensor technology and biomedical engineering, specifically to an ionized flexible integrated physiological signal detection patch and its fabrication method. The ionized flexible integrated physiological signal detection patch includes a flexible substrate; an ionized flexible pressure sensor disposed on the flexible substrate; the ionized flexible pressure sensor includes, from top to bottom, an upper flexible electrode, a sensitive layer, a spacer layer, and a lower flexible electrode; the sensitive layer is a nanocomposite ion gel film with a double-sided random microstructure; a signal processing circuit integrated on the flexible substrate and electrically connected to the upper and lower flexible electrodes of the ionized flexible pressure sensor, used for acquiring, processing, and transmitting physiological signals from the ionized flexible pressure sensor; and a flexible package that integrates the ionized flexible pressure sensor and the signal processing circuit within it.

Description

Technical Field

[0001] This invention relates to the interdisciplinary field of sensor technology and biomedical engineering, specifically to an ionized flexible integrated physiological signal detection patch and its preparation method. Background Technology

[0002] The accurate detection of human physiological signals (such as pulse, respiration, swallowing, etc.) is a core requirement in the field of biomedical engineering, and it plays an irreplaceable role in scenarios such as health monitoring, disease diagnosis, and wearable medical devices.

[0003] With the development of flexible electronics technology, flexible pressure sensors, due to their excellent biocompatibility, fit, and portability, are gradually becoming core devices for detecting human physiological signals. Compared with traditional rigid sensors, they can effectively improve human comfort during the detection process, enabling non-invasive and imperceptible long-term wear, making them more suitable for continuous health monitoring scenarios (such as sleep monitoring and chronic disease management). Physiological signals in health monitoring are often accompanied by dynamic deformation of the human body (such as chest rise and fall during breathing and muscle contraction during exercise). The rigid structure of MEMS sensors cannot respond synchronously with deformation, and may even cause chip damage or performance drift due to deformation stress. The substrate and sensitive layer of flexible sensors have excellent tensile and bending properties, maintaining stable performance under large deformations, and can accurately collect dynamic physiological signals (such as pulse signals and respiratory signals during exercise).

[0004] Current health monitoring devices have a low degree of integration. The separate design of sensing units, signal conditioning modules, and data transmission modules makes system integration difficult. Furthermore, in wearable devices and other applications, they face constraints on both size and power consumption. MEMS sensors require rigid circuit boards, batteries, and packaging components, resulting in a large overall size and weight, making integration into thin and light wearable devices (such as patch-type monitors) difficult. Their rigid structure also limits integration capabilities, preventing the fabrication of flexible patches or textiles. Flexible sensors, on the other hand, can be integrated with flexible circuits and flexible batteries, enabling thinner, more wearable designs. They can even be embedded in clothing, bandages, and other everyday items, offering far greater portability than MEMS sensors.

[0005] Furthermore, existing flexible sensors are mostly single sensing units, lacking integrated design with signal processing and data transmission modules. This necessitates the construction of complex external circuits in practical applications, increasing system size and power consumption. It also makes the system susceptible to signal interference due to inter-module compatibility issues, affecting detection stability. Flexible integrated sensing systems, on the other hand, use flexible substrates (such as PI or PDMS) to integrate the sensor array, flexible circuitry, data acquisition module, and wireless transmission module onto the same flexible substrate. This results in a shorter signal transmission path, lower response latency, and a thinner, more flexible overall design that conforms more closely to human skin and clothing. The system also boasts strong structural stability, resisting environmental damage to the sensing module, minimizing displacement during movement, and significantly improving long-term wear comfort. Summary of the Invention

[0006] The purpose of this invention is to provide an ionized flexible integrated physiological signal detection patch to solve the problems of insufficient detection accuracy, poor adhesion, and complex system of existing flexible sensors.

[0007] To address the aforementioned problems, this invention proposes an ionized flexible integrated physiological signal detection patch, the technical solution of which is as follows: An ionized flexible integrated physiological signal detection patch includes: Flexible substrate; An ionized flexible pressure sensor is disposed on the flexible substrate; the ionized flexible pressure sensor includes an upper flexible electrode, a sensitive layer, a spacer layer and a lower flexible electrode arranged sequentially from top to bottom; the sensitive layer is a nanocomposite ion gel film with a double-sided random microstructure; A signal processing circuit, integrated on the flexible substrate and electrically connected to the upper and lower flexible electrodes of the ionized flexible pressure sensor, is used to acquire, process, and transmit physiological signals from the ionized flexible pressure sensor. A flexible package that integrates the ionized flexible pressure sensor and the signal processing circuitry.

[0008] Furthermore, both the upper and lower surfaces of the sensitive layer have irregular protrusions and depressions, which form a double-sided random microstructure.

[0009] Furthermore, the raw materials of the sensitive layer include thermoplastic polyurethane, multi-walled carbon nanotubes and ionic liquid, wherein the multi-walled carbon nanotubes in the sensitive layer are uniformly dispersed in a gel network formed by thermoplastic polyurethane and ionic liquid.

[0010] Furthermore, the ionic liquid is 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide; the raw material of the spacer layer includes polyethylene terephthalate.

[0011] Furthermore, the spacer layer is made of polyethylene terephthalate single-sided tape.

[0012] Furthermore, the method for preparing the sensitive layer includes the following steps: S1. A uniformly dispersed nanocomposite ionic gel solution is obtained by mixing thermoplastic polyurethane, multi-walled carbon nanotubes and ionic liquid. S2. The nanocomposite ion gel solution is injected into the receiving cavity formed by the gasket mold and the first sandpaper template, and heated to form a pregel film; S3. Cover the pregel film with the second sandpaper template and perform hot pressing treatment so that the morphology of the first rough surface on the first sandpaper template and the second rough surface on the second sandpaper template are respectively replicated to the opposite sides of the pregel film to obtain the sensitive layer.

[0013] Furthermore, the hot pressing treatment is performed at a temperature of 100-120°C for 5-10 minutes; the first sandpaper template and the second sandpaper template may have the same or different mesh counts, ranging from 100 to 10000 mesh.

[0014] Further, the mass ratio of the thermoplastic polyurethane to the ionic liquid is 1:(0.7-1); the mass ratio of the thermoplastic polyurethane to the multi-walled carbon nanotubes is 1:(0.02-0.03).

[0015] Furthermore, the signal processing circuit includes a capacitor signal acquisition module, a data processing main control module, a wireless communication module, and a power supply voltage regulator module; The capacitance signal acquisition module is used to acquire the capacitance change signal of the ionized flexible pressure sensor. The data processing main control module is connected to the capacitance signal acquisition module and is used to process the capacitance change signal; The wireless communication module is connected to the data processing main control module and is used to send the processed capacitance change signal to an external device. The power supply module is used to supply power to the capacitor signal acquisition module, the data processing main control module and the wireless communication module.

[0016] Furthermore, the signal processing circuit also includes a conductive network and passive components.

[0017] Furthermore, the upper flexible electrode is an upper PI-Cu electrode, and the lower flexible electrode is a lower PI-Cu electrode, with the upper PI-Cu electrode in contact with the sensitive layer and the lower PI-Cu electrode in contact with the spacer layer; the flexible package includes an upper silicone encapsulation layer and a lower silicone encapsulation layer, wherein the lower silicone encapsulation layer is the flexible substrate, and the outer surface of the flexible substrate is provided with a breathable layer.

[0018] Furthermore, the side of the upper PI-Cu electrode with copper foil attached is in contact with the upper surface of the sensitive layer, the lower surface of the sensitive layer is in contact with the upper surface of the spacer layer, and the lower surface of the spacer layer is in contact with the side of the lower PI-Cu electrode with copper foil attached.

[0019] This invention also proposes a method for preparing an ionized flexible integrated physiological signal detection patch, the technical solution of which is: A method for preparing an ionized flexible integrated physiological signal detection patch includes the following steps: A. A sensitive layer with a double-sided random microstructure is prepared using the method described above; B. Fabricating an upper flexible electrode and a lower flexible electrode on a flexible substrate; C. A spacer layer, a sensitive layer, and an upper flexible electrode are sequentially covered on the lower flexible electrode to form an ionized flexible pressure sensor; D. Integrate signal processing circuitry on a flexible substrate and electrically connect it to an ionized flexible pressure sensor; E. The ionized flexible pressure sensor and signal processing circuit are integrated into a flexible package.

[0020] Compared with the prior art, this application has the following technical advantages: This invention is an improved version. It increases the pressure contact area through a double-sided random microstructure in the sensitive layer, coupling with the doped material to enhance conductivity and Young's modulus, thereby improving linearity. This allows the sensor to maintain a wide linear range (~450 kPa, R0). 2 =0.999) and high sensitivity (13.5 kPa) -1 This device can detect small signals such as pulse and heartbeat, as well as large signals such as joint twisting and other human motion signals. Its sensor response time is 6ms and recovery time is 9ms, both shorter than the human body's response time. Furthermore, it employs flexible packaging and integration technology with an ionized flexible pressure sensor and signal processing circuitry, resulting in a highly integrated, lightweight, and flexible system. Due to the biocompatibility of the flexible material, the entire system can be permanently attached to human skin without causing irritation, thus achieving the monitoring of human signals. This invention's ionized flexible integrated physiological signal detection patch enables accurate, stable, and convenient detection of human physiological signals.

[0021] The upper and lower surfaces of the sensitive layer both have irregular protrusions and depressions, forming a double-sided random microstructure. This double-sided random microstructure increases the pressure contact area, couples with the doped material, enhances conductivity and Young's modulus, and improves linearity.

[0022] The hot-pressing process is performed at a temperature of 100-120℃ for 5-10 minutes. The first and second sandpaper templates may have the same or different mesh counts, ranging from 100 to 10,000 mesh. These hot-pressing parameters allow the microstructure to be completely replicated onto the ionogel surface while preventing thermal degradation of the TPU material. By adjusting the mesh counts of the first and second sandpaper templates, random double-sided microstructures of different sizes can be obtained.

[0023] The signal processing circuit includes a capacitor signal acquisition module, a data processing main control module, a wireless communication module, and a power supply regulator module. The capacitance signal acquisition module is used to acquire the capacitance change signal of the ionized flexible pressure sensor. The data processing main control module is connected to the capacitance signal acquisition module and is used to process the capacitance change signal; The wireless communication module is connected to the data processing main control module and is used to send the processed capacitance change signal to an external device. The power supply module provides power to the capacitance signal acquisition module, the data processing main control module, and the wireless communication module. In this structure, the data processing main control module filters environmental interference through a preset algorithm to process capacitance change signals; the wireless communication module enables low-power real-time transmission, allowing monitoring data to be transmitted to a mobile phone in real time. This eliminates the constraint of traditional health monitoring devices requiring data to be viewed on a device display, and also allows for monitoring of recovery progress by comparing past and current data. This structure, combined with sensors, forms an integrated collaborative mechanism of 'sensing-acquisition-processing-transmission'. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the ionized flexible integrated physiological signal detection patch of the present invention; Figure 2 This is a physical image of the ionized flexible integrated physiological signal detection patch of the present invention; Figure 3 This is a flowchart illustrating the fabrication process of the ionized flexible pressure sensor of the present invention. Figure 4 This is a flowchart illustrating the fabrication process of the ionized flexible integrated physiological signal detection patch of the present invention; Figure 5 These are scanning electron microscope images of the sensitive layer in Embodiment 1 of the present invention, wherein a is a cross-sectional view and b is a top view; Figure 6 The pressure response time and recovery time of the ionized flexible pressure sensor in Embodiment 1 of the present invention; Figure 7The pressure response test results of the ionized flexible pressure sensor in Embodiment 1 of the present invention; Figure 8 The results of the repeatability test of the ionized flexible pressure sensor in Embodiment 1 of the present invention; Figure 9 This is a diagram illustrating the flexibility of the ionized flexible integrated physiological signal detection patch in Embodiment 1 of the present invention, where a is the state of being attached to the arm, b is the state of being twisted, c is the state of being stretched laterally, and d is the state of being stretched longitudinally. Figure 10 This is a diagram illustrating the use of the ionized flexible integrated physiological signal detection patch for respiratory monitoring in Embodiment 1 of the present invention. Figure 11 This is an APP data graph showing respiratory monitoring using the ionized flexible integrated physiological signal detection patch in Embodiment 1 of the present invention. Figure 12 A magnified view of partial data from the APP used for respiratory monitoring of the ionized flexible integrated physiological signal detection patch in Embodiment 1 of the present invention; Figure 13 This is a wavelet transform diagram of the ionized flexible integrated physiological signal detection patch used for respiratory monitoring in Embodiment 1 of the present invention. In the figure, 1 is an ionized flexible pressure sensor, 2 is an upper PI-Cu electrode, 3 is a sensitive layer, 4 is a spacer layer, 5 is an integrated chip, 6 is a battery, 7 is a conductive network, 8 is a passive device, 9 is a breathable layer, 10 is an upper silicone encapsulation layer, and 11 is a lower silicone encapsulation layer. Detailed Implementation

[0025] As cited in the background section, existing flexible sensors suffer from insufficient detection accuracy, poor fit, and system complexity. Therefore, this invention provides an ionized flexible integrated physiological signal detection patch, comprising a flexible substrate as a base for mounting other devices; an ionized flexible pressure sensor disposed on the flexible substrate; the ionized flexible pressure sensor comprising, from top to bottom, an upper flexible electrode, a sensitive layer, a spacer layer, and a lower flexible electrode; the sensitive layer is a nanocomposite ion gel film with a double-sided random microstructure, which increases the pressure contact area, couples with doped materials, enhances conductivity and Young's modulus, and improves linearity; a signal processing circuit integrated on the flexible substrate and electrically connected to the upper and lower flexible electrodes of the ionized flexible pressure sensor, used for acquiring, processing, and transmitting physiological signals from the ionized flexible pressure sensor; and a flexible package that integrates the ionized flexible pressure sensor and the signal processing circuit within it. This invention employs flexible packaging and integration technology with an ionized flexible pressure sensor and signal processing circuitry. The entire system is highly integrated, lightweight, and flexible. Furthermore, due to the biocompatibility of the flexible material, the entire system can be permanently attached to human skin without causing irritation, enabling the monitoring of human signals. This invention's ionized flexible integrated physiological signal detection patch achieves fully flexible integration of the sensor and circuitry, featuring microstructure-enhanced sensitivity, balancing high sensitivity with a wide linear range. This results in accurate, stable, and convenient detection of human physiological signals, solving the problems of insufficient sensitivity, large system size, and cumbersome wearing in existing technologies.

[0026] Specifically, the method for preparing the sensitive layer includes the following steps: Step 1: Dissolve thermoplastic polyurethane (TPU) in N,N-dimethylformamide (DMF) solvent to obtain TPU solution; Step 2: Select an appropriate amount of ionic liquid and mix it with TPU solution, then add an appropriate amount of multi-walled carbon nanotubes (MWCNTs) to obtain a mixture; put the mixture into an ultrasonic pulverizer, and after thorough mixing by ultrasonic pulverizer, prepare a nanocomposite ionic gel solution; Step 3, lower layer of sandpaper (4×4 cm) for UV laser cutting machine 2 ), top layer of sandpaper (2.9 × 2.9 cm) 2 ) and a 150 µm thick PI tape mold (square hole inner diameter 3×3 cm) 2 ); Step 4: Smoothly attach the PI tape mold onto the lower layer of sandpaper, take out the prepared nanocomposite ion gel solution and drop it into the square hole, transfer the template to a horizontal heating table at 80°C and dry it in a fume hood for 40 minutes to allow the DMF solvent to evaporate completely, and obtain the ion membrane. Step 5: Attach the upper layer of sandpaper to the surface of the ion membrane in the mold, and use a hot press to hot press it at 100-120℃ for 5-10 minutes. After the hot-pressed template is placed in a fume hood for thorough drying, remove the upper layer of sandpaper, and then peel the ion membrane off from the lower layer of sandpaper. Finally, a nanocomposite ion gel film with a double-sided random microstructure is obtained, which is the sensitive layer.

[0027] like Figure 3 and Figure 4 As shown, the method for fabricating an ionized flexible pressure sensor includes: First, PI copper foil is attached to a glass plate spin-coated with a PDMS layer, and laser etching is used to etch a portion of the PI copper foil into the pattern of the set circuit. Secondly, after the pattern is peeled off using water-soluble adhesive tape, it is transferred onto the lower silicone substrate. The lower silicone substrate adheres to the lower PI copper foil, and the PI copper foil forms the lower flexible electrode; at the same time, it forms a conductive network with the patterned circuit. Then, following the steps above, the upper silicone substrate is bonded to the upper PI copper foil, the upper PI copper foil forms the upper flexible electrode, and the sensitive layer and spacer layer are placed between the upper flexible electrode and the lower flexible electrode and arranged and aligned in sequence; Finally, the water-soluble adhesive tape is removed, and silicone is used for bonding and encapsulation to obtain an ionized flexible pressure sensor.

[0028] A method for preparing an ionized flexible integrated physiological signal detection patch includes: First, apply fluorinated ethylene propylene copolymer (FEP) tape to a glass plate to serve as the substrate; Secondly, a layer of silicone is spin-coated onto the substrate using a spin coater as a flexible substrate, namely the lower silicone encapsulation layer. The upper silicone encapsulation layer is obtained in the same way. Next, the upper silicone substrate is bonded to the upper silicone encapsulation layer, and the lower silicone substrate is bonded to the lower silicone encapsulation layer. Then, the sensitive layer and the spacer layer are installed between the upper PI-Cu electrode and the lower PI-Cu electrode; Next, the ionized flexible pressure sensor, capacitive signal acquisition module, data processing main control module, Bluetooth module, power supply voltage regulator module, and matching electronic components are soldered to specific positions in the conductive circuit using reflow soldering technology, and then coated with insulating varnish, and encapsulated using silicone casting, spin coating, and curing. Finally, the two single-layer TPUs are separated from the substrate and hot-pressed into denser TPU filaments using hot-pressing technology. After the flexible system is peeled off from the substrate, the hot-melt TPU filaments are glued to the surface of the silicone substrate under the circuit as a breathable layer, thus producing an ionized flexible integrated physiological signal detection patch.

[0029] Both the flexible substrate and the flexible encapsulation body are made of silicone (Ecoflex).

[0030] The above manufacturing process employs double-sided hot pressing technology and reflow soldering technology, which makes the entire system low in manufacturing cost and suitable for large-scale production on assembly lines.

[0031] The implementation process of the present invention will be described in detail below with reference to specific embodiments. However, those skilled in the art will understand that the following embodiments are for illustrative purposes only and should not be considered as limiting the scope of the invention. It should also be noted that, for ease of description, only the parts related to the invention are shown in the embodiments.

[0032] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present application will now be described in detail with reference to the embodiments.

[0033] It should be noted that the endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0034] I. Embodiments of the Electrostatic Flexible Integrated Physiological Signal Detection Patch of the Present Invention Specific embodiment 1 of the ionized flexible integrated physiological signal detection patch of the present invention: In this embodiment, as Figure 1 , Figure 2 As shown, the ionized flexible integrated physiological signal detection patch includes a flexible substrate; an ionized flexible pressure sensor 1 disposed on the flexible substrate; the ionized flexible pressure sensor 1 includes an upper flexible electrode, a sensitive layer 3, a spacer layer 4, and a lower flexible electrode arranged sequentially from top to bottom; the sensitive layer 3 is a nanocomposite ion gel film with a double-sided random microstructure; a signal processing circuit, which is integrated on the flexible substrate and electrically connected to the upper and lower flexible electrodes of the ionized flexible pressure sensor 1, is used to acquire, process, and transmit the physiological signals of the ionized flexible pressure sensor 1; and a flexible package, which integrates the ionized flexible pressure sensor 1 and the signal processing circuit within it.

[0035] The upper flexible electrode is an upper PI-Cu electrode 2, and the lower flexible electrode is a lower PI-Cu electrode. The upper PI-Cu electrode 2 is in contact with the sensitive layer 3, and the lower PI-Cu electrode is in contact with the spacer layer 4. The flexible encapsulation body includes an upper silicone encapsulation layer 10 and a lower silicone encapsulation layer 11. The lower silicone encapsulation layer 11 is the flexible substrate. A breathable layer 9, which is made of TPU spun fibers, is provided on the outer surface of the flexible substrate. Specifically, the side of the upper PI-Cu electrode 2 with copper foil attached is in contact with the upper surface of the sensitive layer 3, the lower surface of the sensitive layer 3 is in contact with the upper surface of the spacer layer 4, and the lower surface of the spacer layer 4 is in contact with the side of the lower PI-Cu electrode with copper foil attached.

[0036] Specific embodiment 2 of the ionization flexible integrated physiological signal detection patch of the present invention: Based on the above-described technical concept of the present invention, or based on the specific embodiments of the present invention described above, another embodiment is provided below.

[0037] In this embodiment, as Figure 1 and Figure 2 As shown, both the upper and lower surfaces of the sensitive layer 3 have irregular protrusions and depressions, forming a double-sided random microstructure. The raw materials for the sensitive layer 3 include thermoplastic polyurethane, multi-walled carbon nanotubes, and an ionic liquid. In the sensitive layer 3, the multi-walled carbon nanotubes are uniformly dispersed in a gel network formed by the thermoplastic polyurethane and the ionic liquid. The ionic liquid is 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide. The raw material for the spacer layer 4 includes polyethylene terephthalate (PET). Specifically, the spacer layer 4 is made of polyethylene terephthalate (PET) single-sided adhesive tape. The multi-walled carbon nanotubes are nanoscale with a purity of 99%; the 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide has a purity of 97%; and the thermoplastic polyurethane (TPU) is model 1185A.

[0038] Specific embodiment 3 of the ionization flexible integrated physiological signal detection patch of the present invention: Based on the above-described technical concept of the present invention, or based on the specific embodiments of the present invention described above, another embodiment is provided below.

[0039] In this embodiment, as Figure 1As shown, the signal processing circuit includes a capacitance signal acquisition module, a data processing main control module, a wireless communication module, and a power supply regulator module. The capacitance signal acquisition module is used to acquire the capacitance change signal of the ionized flexible pressure sensor 1, which is obtained by passive electronic devices. The data processing main control module is connected to the capacitance signal acquisition module and is used to process the capacitance change signal; here, the data processing main control module is the main control chip. The wireless communication module is connected to the data processing main control module and is used to send the processed capacitance change signal to an external device. The power supply module is used to power the capacitance signal acquisition module, the data processing main control module, and the wireless communication module; here, the power supply module is a battery 6. The wireless communication module is a Bluetooth transmission module. The signal processing circuit also includes a conductive network 7 and a voltage regulator chip, wherein the conductive network 7 is connected to the upper PI-Cu electrode 2 and the lower PI-Cu electrode. The main control chip, Bluetooth chip, and voltage regulator chip are all integrated chips 5.

[0040] II. Examples of the Preparation Method of the Ionized Flexible Integrated Physiological Signal Detection Patch of the Present Invention Example 1 In this embodiment, the method for preparing the sensitive layer 3 includes the following steps: Step 1: Place 1g of TPU powder and 15g of DMF solvent in a reagent bottle to obtain a TPU solution; Step 2: Select 0.7 g of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide and mix it with TPU solution. Add a magnetic stir bar and stir at 110 ℃ for 2 hours on a magnetic stirrer with a speed of 1000 rpm. Then add 0.03 g of MWCNTs and continue stirring for half an hour to initially disperse the MWCNTs in the solution, obtaining a mixture. Place the mixture in an ultrasonic pulverizer and ultrasonically stir at 90 W for 2 hours to ensure uniform dispersion of MWCNTs in the mixture. Then place it in an ultrasonic cleaner and ultrasonically sonicate for 5 minutes to remove air bubbles from the solution, obtaining a nanocomposite ion gel solution. The CAS number of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide is 174899-82-2. Step 3, lower layer of sandpaper (4×4 cm) for UV laser cutting machine 2 ), top layer of sandpaper (2.9 × 2.9 cm) 2 ) and a 150 µm thick PI tape mold (square hole inner diameter 3×3 cm) 2 The upper and lower layers of sandpaper should be 10,000 grit. Step 4: Smoothly attach the PI tape mold onto the lower layer of sandpaper, take out 1.42 g of the prepared nanocomposite ion gel solution and drop it into the square hole, transfer the template to a horizontal heating table at 80℃ and dry it in a fume hood for 40 minutes to allow the DMF solvent to evaporate completely, and obtain the ion membrane. Step 5: Attach the upper layer of sandpaper to the surface of the ion membrane in the mold, and use a hot press to hot press it at 110°C for 8 minutes. After the hot-pressed template is placed in a fume hood for thorough drying, remove the upper layer of sandpaper, and then peel the ion membrane off from the lower layer of sandpaper. Finally, a nanocomposite ion gel film with a double-sided random microstructure is obtained, namely the sensitive layer 3.

[0041] A method for preparing an ionized flexible integrated physiological signal detection patch includes: First, apply fluorinated ethylene propylene copolymer tape to a glass plate to serve as a substrate; Next, 5g of Ecoflex solution was dropped onto the substrate, and then spin-coated at a low speed of 700 rpm for 10 seconds and a high speed of 1400 rpm for 10 seconds using a spin coater. After curing at room temperature for 2 hours, a silicone substrate was obtained. Next, the water-soluble adhesive tape directly adhered the electrode to the etched substrate. Uncured silicone was prepared using the same steps and then spin-coated onto the cured silicone substrate at 700 rpm for 10 seconds and 1800 rpm for 10 seconds using a spin coater. The side of the water-soluble adhesive tape with the electrode attached was then attached to the spin-coated uncured silicone substrate. Air bubbles between the water-soluble adhesive tape and the silicone were removed using a scraper, and the substrate was then cured at room temperature for 3 hours. The residue on the electrode was cleaned with a brush and the electrode was dried. The water-soluble adhesive tape electrode transfer was completed, resulting in an electrode in which the upper silicone substrate and the upper PI-Cu electrode 2 were bonded together. The lower silicone substrate and the lower PI-Cu electrode were bonded together in the same way. Then, the layer-sensitive layer 3 and the spacer layer 4 are installed between the upper PI-Cu electrode 2 and the lower PI-Cu electrode; Next, the capacitor signal acquisition module, data processing main control module, Bluetooth module, power supply voltage regulator module, and their matching passive components are soldered to specific positions in the conductive circuit using reflow soldering technology, and insulating glue is sprayed on to complete the integration of the entire pressure sensing system. Then, silicone is used for casting, spin coating, and curing to complete the encapsulation.

[0042] Finally, the substrate is removed, and TPU is hot-pressed onto the outside of the lower silicone encapsulation layer for spinning.

[0043] Example 2 The only difference between this embodiment and Embodiment 1 is the mesh size of the upper and lower sandpaper used when preparing the sensitive layer 3. Both the upper and lower sandpapers are 1000 mesh.

[0044] Example 3 The only difference between this embodiment and Embodiment 1 is the mesh size of the upper and lower sandpaper used when preparing the sensitive layer 3. The upper sandpaper is 1000 mesh and the lower sandpaper is 10000 mesh.

[0045] Example 4: The only difference between this example and Example 2 is the amount of MWCNTs added when preparing the sensitive layer 3. The mass of MWCNTs is 0.02 g.

[0046] III. Experimental Examples Experimental Example 1 The sensitive layer 3 prepared in Example 1 was examined using a scanning electron microscope, such as... Figure 5 As shown, it can be concluded that the sensitive layer 3 realizes the construction of the double-sided random microstructure of the sensitive layer.

[0047] Experiment Example 2 The ionized flexible pressure sensor prepared in Example 1 was used for pressure detection. Specifically, the press was controlled via a program from the press control terminal, while relevant sensor data was acquired using an LCR digital bridge. The data display terminal extracted the sensor data and press pressure data for analyzing sensor performance, thus completing the pressure detection. Figure 6 As shown, the response time of the ionized flexible pressure sensor is 6ms and the recovery time is 9ms, demonstrating its promising application prospects in high-frequency signal acquisition. The pressure response test results of the ionized flexible pressure sensor are as follows: Figure 7 As shown, it can be concluded that doping with MWCNTs can improve the linearity and sensitivity of the sensor.

[0048] Experimental Example 3 The repeatability stability of the ionized flexible pressure sensor prepared in Example 1 was tested. Specifically, a press was used to cyclically apply load to the ionized flexible pressure sensor to simulate its use in practical applications. The pressure was set to 130 kPa, and the pressure load cycle was 8000 times. The response curve was obtained, thus completing the repeatability stability test. Figure 8 As shown, the ionized flexible pressure sensor maintains a consistent pressure response in both the early and late stages of the cycle, indicating that it possesses good stability and is suitable for applications requiring long-term detection. Experiment Example 4 The flexibility of the ionized flexible integrated physiological signal detection patch prepared in Example 1 was tested. For example... Figure 9 As shown, a) is the state of being attached to the arm, demonstrating fit; b) is the state of being twisted, demonstrating flexibility; c) is the state of being stretched laterally; and d is the state of being stretched longitudinally. It can be concluded that the ionized flexible integrated physiological signal detection patch has good flexibility, can fit well with the skin, and meets the requirements for physiological signal detection.

[0049] Experimental Example 5 The ionized flexible integrated physiological signal detection patch prepared in Example 1 was used for respiratory monitoring. Specifically, the patch was applied to the abdomen, and signals from the patch were received in real-time via a mobile app, thus enabling respiratory monitoring. Figure 10 , 11 As shown in Figures 12 and 13, it can be concluded that, through wavelet transformation, the signal detected by the ionized flexible integrated physiological signal detection patch is the human respiratory signal, indicating that the ionized flexible integrated physiological signal detection patch can monitor physiological signals.

[0050] Therefore, the ionized flexible integrated physiological signal detection patch of the present invention can achieve accurate, stable and convenient detection of human physiological signals.

[0051] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. An ionized flexible integrated physiological signal detection patch, characterized in that, Including flexible substrates; An ionized flexible pressure sensor (1) is disposed on the flexible substrate; the ionized flexible pressure sensor (1) includes an upper flexible electrode, a sensitive layer (3), a spacer layer (4) and a lower flexible electrode arranged sequentially from top to bottom; the sensitive layer (3) is a nanocomposite ion gel film with a double-sided random microstructure; The signal processing circuit is integrated on the flexible substrate and electrically connected to the upper and lower flexible electrodes of the ionized flexible pressure sensor (1) for acquiring, processing and transmitting physiological signals from the ionized flexible pressure sensor (1). A flexible package that integrates the ionized flexible pressure sensor (1) and the signal processing circuit.

2. The ionized flexible integrated physiological signal detection patch according to claim 1, characterized in that, The upper and lower surfaces of the sensitive layer (3) have irregular protrusions and depressions, which form a double-sided random microstructure.

3. The ionized flexible integrated physiological signal detection patch according to claim 1, characterized in that, The raw materials of the sensitive layer (3) include thermoplastic polyurethane, multi-walled carbon nanotubes and ionic liquids. In the sensitive layer (3), the multi-walled carbon nanotubes are uniformly dispersed in a gel network formed by thermoplastic polyurethane and ionic liquids.

4. The ionized flexible integrated physiological signal detection patch according to claim 3, characterized in that, The ionic liquid is 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; the raw material of the spacer layer (4) includes polyethylene terephthalate.

5. The ionized flexible integrated physiological signal detection patch according to claim 3, characterized in that, The method for preparing the sensitive layer (3) includes the following steps: S1. Thermoplastic polyurethane, multi-walled carbon nanotubes and ionic liquid are mixed to obtain a uniformly dispersed nanocomposite ionic gel solution; S2. The nanocomposite ion gel solution is injected into the receiving cavity formed by the gasket mold and the first sandpaper template, and heated to form a pregel film; S3. Cover the pregel film with the second sandpaper template and perform hot pressing treatment so that the morphology of the first rough surface on the first sandpaper template and the second rough surface on the second sandpaper template are respectively copied to the opposite sides of the pregel film to obtain the sensitive layer (3).

6. The ionized flexible integrated physiological signal detection patch according to claim 5, characterized in that, The hot pressing treatment is performed at a temperature of 100-120℃ for 5-10 minutes; the first sandpaper template and the second sandpaper template may have the same or different mesh counts, ranging from 100 to 10000 mesh.

7. The ionized flexible integrated physiological signal detection patch according to claim 5, characterized in that, The mass ratio of the thermoplastic polyurethane to the ionic liquid is 1:(0.7-1); the mass ratio of the thermoplastic polyurethane to the multi-walled carbon nanotubes is 1:(0.02-0.03).

8. The ionized flexible integrated physiological signal detection patch according to claim 1, characterized in that, The signal processing circuit includes a capacitor signal acquisition module, a data processing main control module, a wireless communication module, and a power supply regulator module. The capacitance signal acquisition module is used to acquire the capacitance change signal of the deionized flexible pressure sensor (1); The data processing main control module is connected to the capacitance signal acquisition module and is used to process the capacitance change signal; The wireless communication module is connected to the data processing main control module and is used to send the processed capacitance change signal to an external device. The power supply module is used to supply power to the capacitor signal acquisition module, the data processing main control module and the wireless communication module.

9. The ionized flexible integrated physiological signal detection patch according to claim 1, characterized in that, The upper flexible electrode is an upper PI-Cu electrode (2), the lower flexible electrode is a lower PI-Cu electrode, and the upper PI-Cu electrode (2) is in contact with the sensitive layer (3), and the lower PI-Cu electrode is in contact with the spacer layer (4); the flexible package includes an upper silicone encapsulation layer (10) and a lower silicone encapsulation layer (11), wherein the lower silicone encapsulation layer (11) is the flexible substrate, and the outer surface of the flexible substrate is provided with a breathable layer (9).

10. A method for preparing a flexible integrated physiological signal detection patch, characterized in that, Includes the following steps: A. Prepare a sensitive layer with a double-sided random microstructure using the method described in any one of claims 5-7 (3); B. Fabricating an upper flexible electrode and a lower flexible electrode on a flexible substrate; C. A spacer layer (4), a sensitive layer (3) and an upper flexible electrode are sequentially covered on the lower flexible electrode to form an ionized flexible pressure sensor (1). D. Integrate the signal processing circuit on the flexible substrate and electrically connect it to the ionized flexible pressure sensor (1); E. The ionized flexible pressure sensor (1) and the signal processing circuit are integrated into a flexible package.

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