CN114569908B

CN114569908B - Functional mask capable of being repeatedly used and monitoring breath in real time

Info

Publication number: CN114569908B
Application number: CN202210222801.7A
Authority: CN
Inventors: 王新; 刘文全
Original assignee: Henan University
Current assignee: Henan University
Priority date: 2022-03-09
Filing date: 2022-03-09
Publication date: 2022-10-28
Anticipated expiration: 2042-03-09
Also published as: CN114569908A

Abstract

The application discloses a functional mask capable of being used repeatedly and monitoring respiration in real time, wherein a carrier is a breather valve mask, a sensing integrated unit is arranged on the inner side of a breather valve, the sensing integrated unit comprises a germ and virus killing module and a sensing module, and the germ and virus killing module comprises a metal conductive grid layer with antibacterial and antiviral properties, a heat-resistant substrate and two leads; the sensing module is composed of a single-electrode friction nano generator, a friction layer attached to an electrode is a polymer nanofiber film with easily obtained electrons, an opposite friction layer is a polymer nanofiber film with volatile electrons, and a gasket is clamped between the two friction layers and used for adjusting output electric signals. Through exhaling with inspiratory repetition process, the mechanical energy of human breathing in-process turns into the electric energy to play the effect of real-time respiration monitoring, when not wearing, with two lead wires access DC power supply of germ and virus killing module, the joule heat that the metal electrically conducts the grid layer and produces can play the effect of germ virus killing.

Description

Functional mask capable of being repeatedly used and monitoring breath in real time

Technical Field

The application relates to the technical field of medical protection, in particular to a functional mask capable of being repeatedly used and monitoring breath in real time.

Background

Worldwide outbreaks of the novel coronavirus (COVID-19) have severely affected the global economic growth and human health, which is mainly transmitted via droplets via the respiratory tract. For the vast majority of respiratory infectious viruses and other diseases, wearing a mask is the most effective method of preventing and reducing the spread of such diseases. Therefore, in the face of the casual spread of new coronavirus, governments call for people to wear masks in crowded places. However, the continuous mutation and the prolonged latency of the new coronavirus have resulted in an increasingly difficult control task, and the protective materials such as masks are in serious shortage. The factors causing serious shortage of mask supply are in various aspects, wherein the most fundamental reason is that the common protective masks at present adopt melt-blown non-woven fabrics, and the disposable characteristic generates a large amount of waste masks, so that the load bearing burden is brought to the environment. Although the disposable medical mask can suppress most infectious pathogens, the protective effect may be reduced by wearing the mask for a long time when stubborn pathogens accumulate on the mask, and therefore, the use time of the disposable medical mask is only about 4 to 8 hours. In addition, there are many problems associated with recycling used masks, such as the risk of secondary transmission of infectious agents if not handled properly. For patients infected with the novel coronavirus, the health status of the patients can be monitored in real time while the virus is prevented from being transmitted to other people again. Respiration as an important vital sign can reflect an important indicator of the underlying health condition. Therefore, driven by the international situation of new coronary epidemic pandemic, a real-time monitoring respirator capable of being worn repeatedly is highly needed.

Disclosure of Invention

In view of the above problems, the present application provides a functional mask capable of being used repeatedly and monitoring respiration in real time, which provides real-time monitoring of the respiratory state and constructs an alarm system for sudden change of respiration and sudden stop of respiration of a patient.

The purpose of the invention is realized by the following technical scheme:

a functional mask capable of being used repeatedly and monitoring respiration in real time comprises a mask body and a respiration valve arranged at the central position of the mask body, wherein a sensing integration unit for killing germs and viruses and monitoring the germs and the viruses is arranged on the inner side of the respiration valve, the sensing integration unit comprises a germ and virus killing module and a sensing module, the sensing module is positioned on the inner side and is right close to the mouth and nose respiration position, a signal processing unit and an alarm display unit are arranged on the outer side of the mask body, the alarm display unit is connected with the signal processing unit through a wire, and the signal processing unit is connected with the sensing integration unit through a wire; the sensing integrated unit is connected with an external power supply lead for heating, killing germs and viruses, and the germ and virus killing module consists of a fixed circular ring frame, a metal conductive grid layer with antibacterial and antiviral properties and a heat-resistant substrate with an exhaust hole from outside to inside; the sensing module is composed of an electrode grid layer, a first friction layer for volatile electrons, a gasket and a second friction layer for easily obtaining electrons from outside to inside.

Furthermore, the signal processing unit comprises a noise filtering, signal amplifying and digital-to-analog conversion module for acquiring signals; the alarm display unit comprises a micro display screen, a buzzer and a power management module (the power management module is a module constructed by integrating a development program and hardware on a micro PCB (printed circuit board) in the prior art, wherein the alarm display unit mainly comprises some required functions of an Arduino Uno3 development board).

Further, the heat-resistant substrate is a polyimide film; the material of the metal conductive grid layer is the same as that of the electrode grid layer and is selected from one of silver nanowires, copper nanoparticles, carbon nanotubes and graphene; the fixed circular frame is made of an acrylic plate, and the first friction layer is made of a nylon 6 nanofiber film; the gasket is an adhesive tape with double-sided adhesiveness; the material of the second friction layer is polyvinylidene fluoride.

Further, the vent holes on the heat-resistant substrate are punched on the heat-resistant substrate by adopting a laser spot-shooting technology, the diameter of each hole is 150-250 micrometers, and the air flow of the vent holes is adjusted by the density of the holes.

The sensing module in the sensing integrated unit is a sensor based on a contact separation mode of a friction nano generator, the first friction layer and the second friction layer are mutually contacted and separated through mechanical vibration generated by respiratory airflow, and a characteristic electric signal representing a respiratory state is generated through an electrostatic induction effect.

The characteristic electric signals representing the breathing state generated by the sensing module are subjected to noise filtering and signal amplification through the signal processing unit, and the signals transmitted by the signal processing unit are received by the alarm display unit and are displayed on the micro display after being transcoded.

After the mask is used for a period of time, a direct current power supply is connected to the germ and virus killing module, the germ and virus killing process is carried out through generated Joule heat, the connected direct current power supply is 3.0V, and the generated temperature is 65-70 ℃.

The metal conductive grid layer and the electrode network layer are prepared by winding a conductive silver simple substance grid on a polyimide film by a drawing spinning method, and the specific process is as follows: dissolving silver nitrate and polypyrrolidone in acetonitrile, wherein the concentrations of the polypyrrolidone and the silver nitrate are respectively 0.5 g/mL and 0.2 g/mL, uniformly stirring to obtain yellow viscous liquid, injecting the yellow viscous liquid into a 1mL injector, wherein the inner diameter of a needle head is about 60 micrometers, then fixing the 1mL injector on an injection pump, receiving a self-made plate (the receiving plate is in a square frame shape) by using a direct current rotating motor and a metal frame, respectively adhering a layer of PI film on two sides of the receiving plate as a receiving substrate, the advancing speed of the injection pump is 1 milliliter per hour, and the rotating speed of the self-made receiving plate is 500 r/min to obtain uniform micron-sized single wires, after receiving is finished, heating and processing the PI film attached with a cross grid of a mixture of the silver nitrate and the polypyrrolidone from the receiving plate at 260 ℃ for 2 hours to obtain a conductive silver simple substance grid taking a polyimide film as a substrate, wherein two sides of the polyimide film form conductive silver simple substance grids, one side is taken as an electrode network layer, the other side is taken as a metal conductive grid layer, and two metal wires are directly adhered to the external connection grid lead wires of a power supply lead wire of the metal conductive simple substance grid layer.

The sensing integration unit converts mechanical energy generated by the respiratory airflow into an electric signal through a frictional electrification and electrostatic induction coupling effect, and the signal can map a real-time respiratory state.

The sensitivity of the sensing module is determined by the thicknesses of the first friction layer and the second friction layer of the friction nano-generator and the gap between the first friction layer and the second friction layer.

The sensing module is arranged on the inner side of the mask and is just close to the breathing position of the mouth and the nose, and can directly receive the change of the air flow generated by breathing. The change of the airflow prompts the friction layer to generate an electric signal to be received by the sensing module, and the physiological characteristics of the human breathing state are reflected according to the change of the electric signal.

And the signal processing units are respectively arranged on the outer sides of the masks and are connected with the sensing modules. The real-time electric signals are sent out through the data processing and transmission component.

The reusable breathing monitoring mask is repeatedly embodied in a germ and virus killing module, and after the mask is worn for a certain time, microorganisms and fungi adsorbed on the surface can be repeatedly recycled after being heated by a direct-current power supply.

Drawings

Fig. 1 is a schematic structural view of a functional mask according to the present application;

fig. 2 is an SEM image and an XRD chart of the metal conductive mesh layer of the functional mask of the present application;

fig. 3 is a structural sectional view of a sensing integration unit of the functional mask of the present application;

fig. 4 is a working schematic diagram of a sensing module of the functional mask of the present application;

fig. 5 is a flowchart of a signal processing unit of the mask according to the present application;

fig. 6 is an application scenario of the mask with the function of the present application in respiratory monitoring;

FIG. 7 shows voltage signals generated by the mask of the present application under different breathing conditions;

fig. 8 shows voltage signals and corresponding warning signals generated by the mask with the function of the present application in different breathing states;

FIG. 9 is a schematic view of the electrical heating sterilization and virus killing of the mask, temperature variation graph and stability test graph according to the present application;

FIG. 10 is a comparison of the functional mask of the present application before and after sterilization;

in the figure: 10. the mask comprises a mask body, 20 breathing valves, 30 sensing integrated units, 31 sterilization and virus modules, 32 sensing modules, 310 fixed circular ring frames, 311 metal conductive network layers, 312 heat-resistant substrates, 323 electrode network layers, 324 first friction layers, 325 gaskets, 326 second friction layers, 40 signal processing units, 50 alarm display units and 60 external power supply leads.

Detailed Description

The invention will be further described in detail with reference to the drawings and specific embodiments.

Example 1

The application provides a can use repeatedly and breathe monitoring's function gauze mask in real time, it is inboard through the breather valve with putting into the gauze mask sensing integrated unit, through gaseous exhalation and inspiratory repeated in-process, convert mechanical energy into the electric energy, the signal of telecommunication characteristic of output can the respiratory state of real-time supervision organism along with intensity of respiration and frequency variation. Meanwhile, the existence of the metal conductive mesh layer with the characteristic of killing germs and viruses enables the metal conductive mesh layer to be recycled.

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is further described in detail below with reference to the accompanying drawings in combination with specific embodiments.

Fig. 1 is a schematic structural diagram of a functional mask capable of being used repeatedly and monitoring respiration in real time in an embodiment of the present application.

As can be seen from fig. 1, the mask comprises: a mask body 10 and a breather valve 20 arranged at the center of the mask body 10; a sensing integrated unit 30 integrating sterilization, virus killing and monitoring is arranged on the inner side of the breather valve 20; the outer side of the mask body 10 is provided with a signal processing unit 40 and an alarm display unit 50; the alarm display unit 50 is connected with the signal processing unit 40 through a lead, and the signal processing unit 40 is connected with the sensing integration unit 30 through a lead; the sensing integration unit 30 is connected with an external power lead 60 for heating and killing germs and viruses. The sensing integrated unit 30 includes: the sterilization and virus-killing module 31 and the sensing module 32, wherein the sensing module 32 is positioned at the inner side and is opposite to the position close to the mouth and nose breathing. The germ and virus killing module 31 is composed of a fixed circular ring frame 310, a metal conductive mesh layer 311 and a heat-resistant substrate 312 from outside to inside. The sensor module 32 is composed of an electrode mesh layer 323, a first friction layer 324 of volatile electrons, a pad 325, and a second friction layer 326 of readily available electrons from the outside to the inside.

The components of the reusable respiration monitoring mask of the present application are described in detail below.

Gauze mask body 10 in this application is commercial gauze mask that has the breather valve, and the material is one or several kinds of following materials: non-woven fabrics, melt-blown fabrics, hot air cotton.

The breather valve 20 in the present application is generally composed of a silica gel valve plate and a plastic shell;

the fixed circular ring frame 310 in the application is made of an acrylic plate through cutting, and the plate thickness is 2 mm; the inner and outer diameters were 30 mm and 40 mm, respectively.

The metal conductive grid layer 311 in the present application is formed by a single substance silver grid with a line width of about 10 microns, and both ends of the metal conductive grid layer 311 are respectively connected with an external power supply lead 60.

The heat resistant substrate 312 in this application is composed of a polyimide film with a thickness of 25 microns, and is capable of withstanding high temperatures of 350 ℃.

The electrode grid layer 323 in this application is comprised of elemental silver grids with line widths of about 10 microns.

The first friction layer 324 in this application is made from electrospun nylon 6 nanofiber films (30 to 60 microns in thickness), the method in the references (electrospining and electrospining nanofibers: methods, materials, and applications, chemical reviews, 2019, 119 (8): 5298-5415.).

The shim 325 in this application was cut from double-sided tape having a thickness of about 50 microns, with inner and outer diameters of 30 mm and 40 mm, respectively.

The second friction layer 326 in this application is made from an electrospun polyvinylidene fluoride nanofiber film (thickness 100 to 150 microns), a process in the references (electrospining and electrospinun fibers: methods, materials, and applications, chemical reviews, 2019, 119 (8): 5298-5415.).

The metal conductive grid layer 311 and the electrode network layer 323 in the application are prepared by winding a conductive silver simple substance grid on a polyimide film by a drawing spinning method. The raw materials are silver nitrate and polypyrrolidone respectively, the silver nitrate and the polypyrrolidone are dissolved in acetonitrile, and the concentrations of the polypyrrolidone and the silver nitrate are 0.5 g/mL and 0.2 g/mL respectively. And stirring uniformly to obtain yellow viscous liquid. This was injected into a 1mL syringe with a needle having an inner diameter of about 60 microns. Then, the 1mL syringe was fixed to the injection pump, and a receiving plate (the receiving plate was square) was prepared by using a dc rotary motor and a metal stand. The propelling speed of the injection pump is 1 milliliter per hour, and the rotating speed of the homemade receiving plate is 500 r/min, so that a uniform micron-sized single line is obtained. And respectively adhering a layer of PI film on two sides of the receiving plate to be used as a receiving substrate, after receiving, removing the PI film with the cross grid of a mixture of silver nitrate and polyvinylpyrrolidone from the receiving plate, and heating at 260 ℃ for 2 hours to obtain the conductive silver simple substance grid with the polyimide film as the substrate (the conductive silver simple substance grid is formed on two sides of the polyimide film, one side is used as an electrode network layer 323, the other side is used as a metal conductive grid layer 311, and two lead wires are directly adhered to the surfaces of two ends of the metal conductive grid layer 311 by using a small amount of silver paste to be used as an external power supply lead 60, wherein the silver paste purchase manufacturer is Guangzhou regular script electron type EN-06B 8). As shown in fig. 2, the SEM image shows that the conductive silver grid is composed of horizontally and vertically crossed silver wires. In addition, the XRD pattern of the material is completely matched with that of silver standard card 01-089-3722, and the conductive material is confirmed to be a silver material.

The working principle of the sensing module in the present application is divided into four transient states, and a cross-sectional view of the functional device is shown in fig. 3, in which a fixed circular frame serving as a support base is omitted. When exhaling, first friction layer 324 is brought into contact with second friction layer 326 and an induced charge is generated as a result of the exhaled airflow, as shown in fig. 4 (a). As the pressure of the exhaled gas flow on the second friction layer 326 is reduced, the second friction layer 326 gradually returns to the original equilibrium position, and in the process, induced charges are generated between the first friction layer 324 and the electrode mesh layer 323 due to the electrostatic induction, and a current is generated in an external closed loop, as shown in fig. 4 (B). When aspirating, second friction layer 326 is deformed in the opposite direction to the original direction by the aspirating air stream, resulting in a further increase in the distance between first friction layer 324 and second friction layer 326. When the limit of deformation of the second friction layer 326 is reached, the induction is in electrostatic equilibrium, as shown in fig. 4 (C). As the suction air pressure decreases, the second friction layer 326 is restored from the maximum deformation state to the original equilibrium position. At this time, as the distance between the first friction layer 324 and the second friction layer 326 is reduced, the electrostatic induction between the two is enhanced, and the induced charge distribution between the first friction layer 324 and the electrode mesh layer 323 is changed, so that a reverse current is generated in the closed loop formed by the electrode mesh layer 323, as shown in fig. 4 (D).

The heat resistant substrate 312 in this application is composed of a laser-drilled polyimide film with a film thickness of 25 microns. Wherein the purpose of the perforation is to make the whole device permeable to air. The pore size was about 200 microns and the pore size density was 2 cm x 2 cm containing 400 pores.

The signal processing unit 40 in the present application is composed of a commercial electrostatic amplifier ADA44530-1 and an AD/DA digital-to-analog conversion module PCF8591 (the digital-to-analog conversion module converts the sensing electrical signal into a corresponding high-low level signal, the high level is 5V, and the low level is 0V. Specifically, when the threshold voltage is set to 0.3V, the electrical signal generated by the sensor is higher than the value, the sensing electrical signal is converted into a high level, and when the threshold voltage is lower than the value, the sensing electrical signal is converted into a low level). The electric signals generated by respiration are further amplified by an electrostatic amplifier ADA44530-1, and then are converted into corresponding high-low level signals by a self-made digital-to-analog conversion module.

The alarm display unit 50 consists of an oscilloscope (RIGOL DS 2000A), a commercial low-power-consumption buzzer alarm and an Arduino Uno3 development board. Wherein, the two channels on the oscilloscope (RIGOL DS 2000A) respectively display the real-time respiration electric signal and the high-low level signal (the high level is 5V). The Arduino Uno3 development board is applied to a writing program and controls the function of a buzzer alarm.

The applied electronic components in the application are all selected from commercial low-power-consumption devices, and the principle flow of the alarm system is shown in fig. 5. First, the air pressure generated by the wearer breathing deforms the first friction layer 324 of the sensing module 32 and contacts and rubs against the second friction layer 326, thereby generating an electrical signal under the triboelectric and electrostatic induction coupling effect. The module is used for collecting voltage of 0.3V when the adult breathes normally. Therefore, the voltage of 0.3V serves as the threshold voltage of the determination condition. The signal is further amplified by the signal processing unit 50 and converted into a digital signal by a self-made digital-to-analog conversion module. When the real-time monitoring voltage value exceeds 0.3V, a high level voltage value is generated and is 5V, and when the real-time monitoring voltage value is lower than 0.3V, the high level voltage value is at a low level voltage value and is 0V. And judging whether the digital signal meets the program condition through an uploading program in the microprogram control unit according to the high and low levels serving as a judgment basis. And finally, displaying the electrical signal generated by respiration and the converted digital signal in an oscilloscope in real time.

An application scenario of the reusable respiration monitoring mask in the aspect of respiration monitoring is shown in fig. 6. The reusable respiration monitoring mask can distinguish weak respiration, normal respiration, rapid respiration and deep respiration states, and therefore the respiration monitoring mask can be used for monitoring the health state of a patient in real time as a sensor. By further analyzing the intensity and frequency of these output electrical signals, the current breathing state of the subject can be easily discerned, as shown in fig. 7. The sensitivity of the sensing module 32 is dependent upon the thickness and spacing of the first and second friction layers 324, 326.

The reusable breathing state monitoring mask of the present application demonstrates in use as shown in figure 8. The scenario of the demonstration includes three respiratory states: the first is a situation that the breathing state is changed from normal to jerky; the second is a scenario where deep breathing becomes sudden cessation of breathing; the third is the sudden breathing event from a weak breath.

In the first scenario, the change in breathing frequency is a major feature of the scenario. The respiratory rate of an adult in a healthy state is generally 12 to 20 times per minute, the respiratory rate is converted into a range of 0.2 to 0.33 Hz, and the condition of tachypnea when the respiratory rate exceeds the range belongs to the tachypnea condition. In order to be able to accurately determine the breathing frequency in this case, a 0.4 Hz threshold is set. The micro-program control unit is written with a discrimination program, when the electrical signal generated by respiration is higher than a threshold voltage (0.3V), a corresponding high level is output (the voltage value is 5V), and when the electrical signal generated by respiration is lower than the threshold voltage (0.3V), a corresponding low level is output (the voltage value is 0V). In the continuous breathing process, the generated electric signal has periodicity, and the high-low level signal formed by conversion of the digital-to-analog conversion module also has periodicity and can be converted into the breathing frequency. When the respiratory frequency is larger than or equal to the preset 0.4 Hz threshold value, the judgment basis is that the respiratory frequency is continued for more than 2 seconds, and the judgment condition is taken. When the conditions are met, the control program feeds back to the buzzer alarm to make the buzzer alarm, and the electric signal in the process is shown in fig. 8 (a).

In the second scenario, the variation of the strength of the electrical signal generated by respiration is the main characteristic of the scenario. The electrical signal generated during deep breathing is larger than that generated during normal breathing. Therefore, normal respiration of an adult produces a voltage value of 0.3V as a threshold voltage, and when the threshold is exceeded, it is the case of deep respiration. The micro-program control unit is written with a discrimination program, when the electrical signal generated by respiration is higher than a threshold voltage (0.3V), a corresponding high level is output (the voltage value is 5V), and when the electrical signal generated by respiration is lower than the threshold voltage (0.3V), a corresponding low level is output (the voltage value is 0V). In the process of deep breathing, the high-low level signals obtained by the digital-to-analog conversion module are used as a judgment basis and are continued for more than 5 seconds to be used as a judgment condition. When the condition is satisfied, it is determined as a deep breathing state. Then, with the sudden stop of breathing, the electrical signal generated therewith will also disappear, the high level signal generated by the digital-to-analog conversion module will also disappear, the microprogram control unit feeds back to the buzzer alarm to make it give an alarm, and the electrical signal generated in the process is shown in fig. 8 (b).

In the third scenario, the variation of the strength of the electrical signal generated by respiration is the main characteristic of the scenario. The electrical signal generated during weak breathing is smaller than that generated during normal breathing. Thus, normal breathing in adults produces a voltage value of 0.3V as the threshold voltage, which, when lower than this threshold and non-zero, is the case of weak breathing. The micro-program control unit is written with a discrimination program, when the electrical signal generated by respiration is lower than a threshold voltage (0.3V) and is nonzero, a high level (the voltage value is 5V) is correspondingly output, and when the electrical signal generated by respiration is equal to 0V, a low level (the voltage value is 0V) is correspondingly output. In the breathing process, the high-low level signal obtained by the digital-to-analog conversion module is used as a judgment basis and is continued for more than 5 seconds to be used as a judgment condition. And when the condition is met, judging the state of weak respiration. Then, with the sudden stop of breathing, the electrical signal generated therewith will also disappear, the high level signal generated by the digital-to-analog conversion module will also disappear, the microprogram control unit feeds back to the buzzer alarm to make it give an alarm, and the electrical signal generated in the process is shown in fig. 8 (c).

Reusable respiration monitoring mask (12.5 × 12.5 mm) in the present application ² ) Reuse is achieved by heating the germ-killing and virus-killing module 31 of germ-killing nature. The test principle of heating sterilization and the temperature change are shown in fig. 9. When the mask is taken down after being used for several hours, 1.5V, 3.0V and 4.5V direct current power supplies are respectively connected to two ends of an external power supply lead 60 connected with the metal conductive grid layer 311, and then the temperature of the surface of the germ killing module is collected by using an infrared thermal imager. The surface temperature was maintained at about 38.7, 64.4 and 103 deg.C respectively when heating was continued for 10 min at three different voltages. In addition, in order to ensure that the mask has double functions of good sterilization effect and reusability, a 3.0V direct current power supply is selected for subsequent tests, and after 5 times of thermal stability cycle tests, the surface temperature of the mask is maintained at about 67.5 ℃. Finally, in order to test the sterilization capability of the strain, escherichia coli is selected as an experimental body, the strain is incubated on a sterilization and virus killing module 31, then direct current of 3.0V is introduced into the sterilization module for about 20 minutes, a comparison graph, the colony count and the bacteriostasis rate before and after electrification are shown in figure 10, and the bacteriostasis rate can reach 96.41 percent.

The above-mentioned embodiments are further described in detail for the purpose of illustrating the invention, and it is to be understood that the above-mentioned embodiments are only illustrative of the present invention and are not intended to limit the present disclosure, and any modifications, equivalents, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A functional mask capable of being used repeatedly and monitoring respiration in real time comprises a mask body and a breather valve arranged at the central position of the mask body, and is characterized in that a sensing integrated unit for killing germs and viruses and monitoring the germs and the viruses is arranged on the inner side of the breather valve, the sensing integrated unit comprises a germ-killing module, a virus-killing module and a sensing module, the sensing module is positioned on the inner side and just close to the mouth and nose breathing position, a signal processing unit and an alarm display unit are arranged on the outer side of the mask body, the alarm display unit is connected with the signal processing unit through a wire, and the signal processing unit is connected with the sensing integrated unit through a wire; the sensing integrated unit is connected with an external power supply lead for heating, killing bacteria and viruses, and the bacteria and virus killing module consists of a fixed circular ring frame, a metal conductive grid layer with antibacterial and antiviral properties and a heat-resistant substrate with an exhaust hole from outside to inside; the sensing module consists of an electrode grid layer, a first friction layer, a gasket and a second friction layer from outside to inside; the heat-resistant substrate is a polyimide film; the metal conductive grid layer and the electrode grid layer are made of the same material and are silver nanowires; the fixed circular frame is made of an acrylic plate, and the first friction layer is made of a nylon 6 nanofiber film; the gasket is an adhesive tape with double-sided adhesiveness; the second friction layer is made of polyvinylidene fluoride; the metal conductive grid layer and the electrode network layer are prepared by winding a conductive silver simple substance grid on the polyimide film by a drawing spinning method; the specific processes of the metal conductive grid layer and the electrode network layer are as follows: dissolving silver nitrate and polyvinylpyrrolidone in acetonitrile, wherein the concentrations of the polyvinylpyrrolidone and the silver nitrate are respectively 0.5 g/mL and 0.2 g/mL, uniformly stirring to obtain yellow viscous liquid, injecting the yellow viscous liquid into a 1mL injector, wherein the inner diameter of a needle head is 60 micrometers, then fixing the 1mL injector on an injection pump, respectively adhering a layer of polyimide film on two sides of a receiving plate to be used as a receiving substrate, the advancing speed of the injection pump is 1mL per hour, and the rotating speed of the receiving plate is 500 r/min to obtain uniform micron-sized single wires, after receiving, removing the polyimide film attached with a cross grid with a mixture of the silver nitrate and the polyvinylpyrrolidone from the receiving plate, heating at 260 ℃ for 2 hours to obtain a conductive silver simple substance grid with the polyimide film as the substrate, wherein one side of the conductive silver simple substance grid is used as an electrode network layer, the other side of the conductive metal conductive simple substance grid layer is used as a metal conductive grid layer, and two leads are directly adhered to the surfaces of two ends of the metal conductive simple substance grid layer by silver paste to be used as external power supply leads.

2. The functional mask according to claim 1, wherein the signal processing unit comprises a noise filtering, signal amplification and digital-to-analog conversion module for collecting signals; the alarm display unit comprises a micro display screen, a buzzer and a power supply management module.

3. The functional mask according to claim 1 wherein said vent holes in said heat resistant substrate are perforated by laser spot irradiation technique with hole diameter of 150 to 250 microns, and the air flow rate of the vent holes is adjusted by the hole density.

4. The functional mask according to claim 1, wherein the sensing module in the sensing integrated unit is a sensor based on a contact separation mode of a friction nano generator, and the first friction layer and the second friction layer are contacted and separated from each other by mechanical vibration generated by respiratory airflow, and generate a characteristic electrical signal representing a respiratory state by an electrostatic induction effect.

5. The functional mask according to claim 4, wherein the characteristic electrical signals representing the breathing state generated by the sensing module are subjected to noise filtering and signal amplification by the signal processing unit, and the signals transmitted by the signal processing unit are received by the alarm display unit and transcoded and displayed on the micro-display.

6. The functional mask according to claim 1, wherein after the mask is used for a period of time, a DC power supply is connected to the germ and virus killing module, the germ and virus killing process is performed by the generated Joule heat, the connected DC power supply is 3V, and the generated temperature is 65-70 ℃.