A filtering device and a mask with an electrospun nanofiber cloth

Abstract

The present invention provides a filtering device and a mask having an electrospun nanofiber cloth, comprising: an electrospun nanofiber cloth and a melt-blown nonwoven fabric; the melt-blown nonwoven fabric is disposed on at least one side of the electrospun nanofiber cloth to form a filtering structure of two or more layers with the electrospun nanofiber cloth; the filtering efficiency percentage of the melt-blown nonwoven fabric for particles with a particle size of 0.02 - 10 μm is M; the filtering efficiency percentage of the electrospun nanofiber cloth for particles with a particle size of 0.02 - 10 μm is N; then it satisfies: M / N = 1.05 - 1.6. Through the above setting of the filtering efficiency value, the present invention forms a filtering combination of the electrospun nanofiber cloth and the melt-blown nonwoven fabric, having a hierarchical filtering structure with different filtering effects on substances such as solid particles, bacteria, viruses, etc. of different sizes, and at the same time having a low gram weight and a high porosity when used, so that when there is a high-speed airflow passing through, it will not produce a blocking effect on the airflow, and thus will not cause an increase in the resistance pressure drop.

Description

Technical Field

[0001] The present invention belongs to the field of respiratory protection, and particularly relates to a filtering device and a mask having an electrospun nanofiber cloth. Background Art

[0002] With the enhancement of people's awareness of protection, the frequency of using masks is getting higher and higher. However, ordinary cotton masks can only block larger particles, and their main function is to keep warm. Tiny particles in the air can still penetrate the cotton masks and enter the human body.

[0003] Although the meltblown layer in the meltblown non-woven fabric has a good filtering effect on larger particles, some smaller particles can still penetrate the meltblown non-woven fabric and enter the human body, making the filtering effect of the meltblown non-woven fabric mask unsatisfactory.

[0004] In the prior art, high-performance electrospun nanofiber filter materials need to have the characteristics of high efficiency and low resistance. Conventional high-performance electrospun nanofiber filter materials rely on the structural characteristics of the materials themselves (pore size, packing density, etc.) to filter particles. Usually, they can have high efficiency while also having a high pressure resistance, resulting in poor ventilation ability. Therefore, it is very difficult to achieve an effective balance between filtration efficiency and pressure resistance only by the structural characteristics of high-performance electrospun nanofibers themselves, and it cannot meet the use standards of high-efficiency filtration and low resistance.

[0005] In summary, the products of the prior art cannot take into account both the filtering effect and the air flow resistance, and it is necessary to improve the existing products. Summary of the Invention

[0006] The purpose of the present invention is to provide a filtering device and a mask having an electrospun nanofiber cloth, which can ensure excellent filtering performance while not blocking the air flow, thereby not causing an increase in resistance pressure drop.

[0007] To achieve the above purpose, a filtering device having an electrospun nanofiber cloth provided by the present invention includes:

[0008] An electrospun nanofiber cloth;

[0009] A meltblown non-woven fabric, which is disposed on at least one side of the electrospun nanofiber cloth and forms a filtering structure of two or more layers with the electrospun nanofiber cloth;

[0010] The relationship between the fiber diameters of the electrospun nanofiber cloth and the meltblown non-woven fabric is inversely correlated, so that when the fiber diameter of the meltblown non-woven fabric increases, the fiber diameter of the electrospun nanofiber cloth decreases;

[0011] Set the filtration efficiency percentage of the melt-blown nonwoven fabric for particles with a particle size of 0.02 - 10 μm to M, and set the filtration efficiency percentage of the electrospun nanofiber cloth for particles with a particle size of 0.02 - 10 μm to N; then it satisfies: M / N = 1.05 - 1.6, M is 80 - 96%, and N is 70 - 93%.

[0012] Furthermore, the relationship between the fiber diameters of the electrospun nanofiber cloth and the melt-blown nonwoven fabric satisfies the following inverse proportional function:

[0013] y = 0.5 / x;

[0014] x is the fiber diameter of the melt-blown nonwoven fabric;

[0015] y is the fiber diameter of the electrospun nanofiber cloth.

[0016] Alternatively, the relationship between the fiber diameters of the electrospun nanofiber cloth and the melt-blown nonwoven fabric satisfies the formula:

[0017] x = y 2 - 10.6y + 6.05;

[0018] x is the fiber diameter of the melt-blown nonwoven fabric;

[0019] y is the fiber diameter of the electrospun nanofiber cloth.

[0020] Furthermore, the fiber diameter of the melt-blown nonwoven fabric is 1 - 5 μm; the fiber diameter of the electrospun nanofiber cloth is 0.1 - 0.5 μm;

[0021] The fiber diameter of the melt-blown nonwoven fabric is 5 μm;

[0022] The fiber diameter of the electrospun nanofiber cloth is 0.1 μm;

[0023] Or:

[0024] The fiber diameter of the melt-blown nonwoven fabric is 1 μm;

[0025] The fiber diameter of the electrospun nanofiber cloth is 0.5 μm.

[0026] Furthermore, the grammage of the melt-blown nonwoven fabric is: 10 - 40;

[0027] The grammage of the electrospun nanofiber cloth is: 0.05 - 0.5.

[0028] Furthermore, the porosity of the electrospun nanofiber cloth is 1.10 - 1.29 times that of the melt-blown nonwoven fabric, and the porosity of the melt-blown nonwoven fabric is 70 - 90%.

[0029] Further, the melt-blown non-woven fabric is disposed on one side of the electrospun nanofiber fabric.

[0030] A mask with an electrospun nanofiber fabric, comprising:

[0031] A mask body, including an inner layer and an outer layer, the inner layer being used to fit against the user's face;

[0032] A filtering device as described in the foregoing solution, disposed between the inner layer and the outer layer;

[0033] The melt-blown non-woven fabric is disposed on at least one side of the electrospun nanofiber fabric to support the electrospun nanofiber fabric.

[0034] The inner layer includes non-woven fabric;

[0035] And / or, the outer layer includes non-woven fabric.

[0036] The above-mentioned mask with an electrospun nanofiber fabric further includes a strap:

[0037] The strap is used to hold the mask body on the user's face.

[0038] Further, the strap includes ear-hook type, tie type or head-loop type.

[0039] Further, the mask body includes a flat type or a three-dimensional type.

[0040] The present invention has at least the following beneficial effects: Through the above setting of the filtration efficiency value, the present invention forms a filtration combination of an electrospun nanofiber fabric and a melt-blown non-woven fabric, and has a hierarchical filtration structure with different filtration effects on substances such as solid particles, bacteria, and viruses of different sizes. The melt-blown non-woven fabric in the present invention has an electrostatic adsorption effect due to the electret effect, has a good filtration effect on larger particles, and can form a larger pore structure, which is beneficial to the smooth passage of air flow; while the electrospun nanofiber fabric has excellent filtration performance for ultrafine particles. By the relationship between the filtration efficiency values described in the present invention, the filtration efficiency value of the electrospun nanofiber fabric used is determined, so that the gas resistance of the filtration device described in the present invention is very small and will not cause an increase in the resistance pressure drop, ensuring the balance between the filtration effect and the air flow resistance. The filtration structure described in the present invention can ensure excellent filtration performance without blocking the air flow, thereby not causing an increase in the resistance pressure drop. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0042] Figure 1It is a stacked diagram of the meltblown nonwoven fabric and the electrospun nanofiber fabric according to an embodiment of the present invention.

[0043] Figure 2 It is an electron microscope image of the combination of the meltblown nonwoven fabric and the electrospun nanofiber fabric according to an embodiment of the present invention.

[0044] Figure 3 It is a stacked diagram of Embodiment 2 of the present invention.

[0045] Figure 4 It is a schematic diagram of a mask according to Embodiment 2 of the present invention.

[0046] In the figure: 1 - mask body, 12 - inner layer, 11 - outer layer, 2 - filtering device, 21 - meltblown nonwoven fabric, 22 - electrospun nanofiber fabric, 3 - strap. Detailed implementation manners

[0047] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0048] The following describes the specific implementation of the present invention in detail with reference to specific embodiments:

[0049] Embodiment 1

[0050] Refer to the attached drawings of the specification Figure 1-2 There is provided a filtering device 2 having an electrospun nanofiber fabric, including:

[0051] The electrospun nanofiber fabric 22;

[0052] The meltblown nonwoven fabric 21, and the meltblown nonwoven fabric 21 is disposed on at least one side of the electrospun nanofiber fabric 22 to form a filtering structure with two or more layers with the electrospun nanofiber fabric 22;

[0053] The relationship between the fiber diameters of the electrospun nanofiber fabric 22 and the meltblown nonwoven fabric 21 is inversely correlated;

[0054] The filtration efficiency percentage of the meltblown nonwoven fabric 21 for particles with a particle size of 0.02 - 10 μm is M; the filtration efficiency percentage of the electrospun nanofiber fabric 22 for particles with a particle size of 0.02 - 10 μm is N; then it satisfies: M / N = 1.05 - 1.6, M / N = 1.05 - 1.6, M is 80 - 96%, and N is 70 - 93%.

[0055] Such as Figure 1Shown is a preferred embodiment where the melt-blown nonwoven fabric 21 is disposed on one side of the electrospun nanofiber fabric 22 to support the electrospun nanofiber fabric 22. When the melt-blown nonwoven fabric 21 is a single layer, the melt-blown nonwoven fabric 21 and the electrospun nanofiber fabric 22 form a two-layer filtration structure. When the melt-blown nonwoven fabric 21 is multiple layers, the melt-blown nonwoven fabric 21 and the electrospun nanofiber fabric 22 form a multi-layer filtration structure. In another embodiment, the melt-blown nonwoven fabric 21 can also be disposed on both sides of the electrospun nanofiber fabric 22 simultaneously.

[0056] In Figure 2 , the thick fibers below are the fibers of the melt-blown nonwoven fabric 21, and the thin fibers and bead-like structures above are the fiber structure of the electrospun nanofiber fabric 22. The surface of the electrospun nanofiber fabric 22 in this embodiment has a spider-web-like microporous structure, with very complex changes such as network connectivity, pore nesting, and pore channel bending in the three-dimensional structure, making it have excellent surface filtration performance.

[0057] The filtration efficiency value of the melt-blown nonwoven fabric 21 for particles of 0.02 - 10 μm is 1.05 - 1.6 times that of the electrospun nanofiber fabric 22.

[0058] Furthermore, the relationship between the fiber diameters of the electrospun nanofiber fabric and the melt-blown nonwoven fabric satisfies an inverse proportional function relationship as follows:

[0059] y = 0.5 / x;

[0060] x is the fiber diameter of the melt-blown nonwoven fabric 21;

[0061] y is the fiber diameter of the electrospun nanofiber fabric 22.

[0062] Preferably, the fiber diameter of the melt-blown nonwoven fabric 21 is 5 μm, and the fiber diameter of the electrospun nanofiber fabric 22 is 0.1 μm.

[0063] Alternatively, the relationship between the fiber diameters of the electrospun nanofiber fabric 22 and the melt-blown nonwoven fabric 21 can also be calculated by the following formula:

[0064] x = y 2 - 10.6y + 6.05;

[0065] x is the fiber diameter of the melt-blown nonwoven fabric 21; y is the fiber diameter of the electrospun nanofiber fabric 22.

[0066] Preferably, the fiber diameter of the melt-blown nonwoven fabric 21 is 5 μm, and the fiber diameter of the electrospun nanofiber fabric 22 is 0.1 μm.

[0067] As can be seen from the above two calculation methods, if the fiber diameter of the meltblown non-woven fabric 21 approaches the maximum value, the fiber diameter of the electrospun nanofiber fabric 22 approaches the minimum value to facilitate cooperation in filtration efficiency.

[0068] Furthermore, the grammage of the meltblown non-woven fabric 21 is: 10 - 40; the grammage of the electrospun nanofiber fabric 22 is: 0.05 - 0.5; the porosity of the electrospun nanofiber fabric 22 is 1.10 - 1.29 times that of the meltblown non-woven fabric, and the porosity of the meltblown non-woven fabric is 70 - 90%.

[0069] In a specific embodiment, it is set that the filtration efficiency of the meltblown non-woven fabric for particles of 0.02 - 10 μm is 93%, and the filtration efficiency of the electrospun nanofiber fabric for particles of 0.02 - 10 μm is 72%. At this time, M / N = 1.3. It is further set that the meltblown non-woven fabric 21 is arranged on one side of the electrospun nanofiber fabric 22 to support the electrospun nanofiber fabric 22, and the meltblown non-woven fabric 21 and the electrospun nanofiber fabric 22 form a two-layer filtration structure. The grammage of the meltblown non-woven fabric 21 is 30, and the grammage of the electrospun nanofiber fabric 22 is 0.3. The porosity of the meltblown non-woven fabric is 80%, and the porosity of the electrospun nanofiber fabric 22 is 92%.

[0070] In the above specific embodiment, the fiber diameter of the meltblown non-woven fabric is 1 - 5 μm, and the fiber diameter of the electrospun nanofiber fabric is 0.1 - 0.5 μm. Taking the fiber diameters of the meltblown non-woven fabric and the electrospun nanofiber fabric as variables, various combinations as shown in Table I can be obtained:

[0071] Meltblown non-woven fabric Electrospun nanofiber fabric The first combination Fiber diameter 1.5μm 0.33μm The second combination Fiber diameter 2μm 0.25μm The third combination Fiber diameter 4.5μm 0.11μm The fourth combination Fiber diameter 6.5μm 0.7μm The fifth combination Fiber diameter 0.6μm 0.05μm

[0072] As can be seen from Table I, the data of the first combination to the third combination are respectively within the scope of the present invention; the fourth combination and the fifth combination exceed the scope of this application and are used as a control group.

[0073] Furthermore, for the above five different embodiments, tests are respectively carried out under the GB / T 32610-2016 standard: the filtration efficiency of saline aerosol and the saline filtration resistance are tested. The filtration efficiency of saline aerosol and the saline filtration resistance are respectively tested. The test data of each scheme in this embodiment are the average values obtained from testing 10 samples. The test results are shown in Table II:

[0074]

[0075] Specific principle analysis: If the fiber diameter of the meltblown non-woven fabric 21 is relatively large, its pore size will be relatively large, and the physical barrier effect will be weak (even if there is an electrostatic adsorption effect caused by electret, a physical barrier effect must be used in combination to achieve the best filtration efficiency). At this time, if the fiber diameter of the electrospun nanofiber cloth 22 used in combination is not considered, or the fiber diameter of the electrospun nanofiber cloth 22 is also relatively large, such as in Comparative Scheme 1, the filtration device formed by the combination of the two will not meet the filtration efficiency standard, and the effect of such a combination will be far less than expected. However, if the fiber diameter of the electrospun nanofiber cloth 22 used in combination is specifically matched with the fiber diameter of the meltblown non-woven fabric 21 to obtain the fiber diameter of the electrospun nanofiber cloth 22, the defect of the meltblown non-woven fabric 21 in terms of physical barrier can be compensated for.

[0076] Conversely, if the fiber diameters of the meltblown non-woven fabrics 21 are all relatively small, such as in Comparative Scheme 2, the pore sizes will all be relatively small, and the physical barrier effect will be relatively ideal. At this time, if the fiber diameter of the electrospun nanofiber cloth 22 used in combination is not considered, or the diameter of the electrospun nanofiber cloth 22 is also relatively small, the breathing resistance after the two are combined will be too large, resulting in a serious decline in application value. In the present invention, the fiber diameter of the electrospun nanofiber cloth 22 used in combination is matched with the fiber diameter of the meltblown non-woven fabric 21 to obtain the fiber diameter of the electrospun nanofiber cloth 22, which can improve the breathing resistance to the greatest extent while achieving an increase in filtration efficiency.

[0077] Combined with Table I and Table II, it can be seen that by comparing Embodiments 1 to 3, matching the fiber diameter of the electrospun nanofiber cloth 22 used in combination with the fiber diameter of the meltblown non-woven fabric 21 can improve the filtration effect on the premise of ensuring air permeability. In the above Table I and Table II, by comparing with the national standard GB / T 32610-2006 for daily protective masks, it can be clearly seen that Embodiments 1 to 3 are stable in terms of the filtration efficiency of saline aerosol and the saline filtration resistance, and can improve the filtration effect on the premise of ensuring air permeability. If the optimal combination is selected, the effect of Embodiment 3 is relatively balanced and can be used as the optimal combination.

[0078] Example 2

[0079] See the attached specification Figure 1-4, it is a mask with an electrospun nanofiber cloth 22, including a mask body 1 and a filtering device 2. The mask body 1 includes an outer layer 11 and an inner layer 12. In this embodiment, the inner layer 12 and the outer layer 11 are non-woven fabrics. The inner layer 12 is used to fit the user's face, and the filtering device 2 is arranged between the inner layer 12 and the outer layer 11. Specifically, the filtering device 2 includes an electrospun nanofiber cloth 22 and a melt-blown non-woven fabric 21. The melt-blown non-woven fabric 21 is arranged on the inner side of the electrospun nanofiber cloth 22 to support the electrospun nanofiber cloth 22. The relationship between the fiber diameters of the electrospun nanofiber cloth 22 and the melt-blown non-woven fabric 21 is inversely correlated; the filtration efficiency percentage of the melt-blown non-woven fabric 21 for particles with a particle size of 0.02-10μm is M; the filtration efficiency percentage of the electrospun nanofiber cloth 22 for particles with a particle size of 0.02-10μm is N; then it satisfies: M / N = 1.05-1.6, M / N = 1.05-1.6, M is 80-96%, and N is 70-93%.

[0080] In Figure 2 , the thick fibers below are the fibers of the melt-blown non-woven fabric 21, and the thin fibers and bead-like structures above are the fiber structure of the electrospun nanofiber cloth 22. The surface of the electrospun nanofiber cloth 22 in this embodiment has a spider-web-like microporous structure, and there are very complex changes such as network connectivity, hole nesting, and pore channel bending in the three-dimensional structure, making it have excellent surface filtration performance.

[0081] The filtration efficiency value of the melt-blown non-woven fabric 21 for particles with a size of 0.02-10μm is 1.05-1.6 times that of the electrospun nanofiber cloth 22.

[0082] Furthermore, the relationship between the fiber diameters of the electrospun nanofiber cloth and the melt-blown non-woven fabric satisfies an inverse proportional function relationship, as follows:

[0083] y = 0.5 / x;

[0084] x is the fiber diameter of the melt-blown non-woven fabric 21;

[0085] y is the fiber diameter of the electrospun nanofiber cloth 22.

[0086] Preferably, the fiber diameter of the melt-blown non-woven fabric 21 is 5μm, and the fiber diameter of the electrospun nanofiber cloth 22 is 0.1μm.

[0087] Or, the relationship between the fiber diameters of the electrospun nanofiber cloth 22 and the melt-blown non-woven fabric 21 can also be calculated by the following formula:

[0088] x = y 2 -10.6y + 6.05;

[0089] x is the fiber diameter of the meltblown non-woven fabric 21; y is the fiber diameter of the electrospun nanofiber fabric 22.

[0090] Preferably, the fiber diameter of the meltblown non-woven fabric 21 is 5 μm, and the fiber diameter of the electrospun nanofiber fabric 22 is 0.1 μm.

[0091] From the above two calculation methods, it can be seen that if the fiber diameter of the meltblown non-woven fabric 21 approaches the maximum value, the fiber diameter of the electrospun nanofiber fabric 22 approaches the minimum value to facilitate cooperation in filtration efficiency.

[0092] Furthermore, the grammage of the meltblown non-woven fabric 21 is: 10 - 40; the grammage of the electrospun nanofiber fabric 22 is: 0.05 - 0.5; the porosity of the electrospun nanofiber fabric 22 is 1.10 - 1.29 times that of the meltblown non-woven fabric 21, and the porosity of the meltblown non-woven fabric 21 is 70 - 90%.

[0093] The mask of this embodiment with the electrospun nanofiber fabric 22 further includes a strap 3: the strap 3 is used to hold the mask body 1 on the user's face. Preferably, the strap 3 includes ear-hook type, tie type or head-loop type.

[0094] In this embodiment, the mask body 1 includes a flat type or a three-dimensional type according to needs.

[0095] In a specific embodiment, it is set that the strap 3 is of the ear-hook type and the mask body 1 is of the three-dimensional type. It is set that the filtration efficiency of the meltblown non-woven fabric for particles of 0.02 - 10 μm is 93%, and the filtration efficiency of the electrospun nanofiber fabric for particles of 0.02 - 10 μm is 72%. At this time, M / N = 1.3. It is further set that the meltblown non-woven fabric 21 is arranged on one side of the electrospun nanofiber fabric 22 to support the electrospun nanofiber fabric 22, and the meltblown non-woven fabric 21 and the electrospun nanofiber fabric 22 form a two-layer filtration structure. The grammage of the meltblown non-woven fabric 21 is 30, and the grammage of the electrospun nanofiber fabric 22 is 0.3. The porosity of the meltblown non-woven fabric is 80%, and the porosity of the electrospun nanofiber fabric 22 is 92%.

[0096] In the above specific embodiment, the fiber diameter of the meltblown non-woven fabric is 1 - 5 μm, and the fiber diameter of the electrospun nanofiber fabric is 0.1 - 0.5 μm. Taking the fiber diameters of the meltblown non-woven fabric and the electrospun nanofiber fabric as variables, various combinations as shown in Table III can be obtained:

[0097]

[0098] According to Table III, the data of the sixth combination to the eighth combination are respectively within the scope of this embodiment; the ninth combination and the tenth combination exceed the scope of this embodiment and are used as the control group.

[0099] In this embodiment, the sixth to tenth combination schemes are assigned to form the inner and outer layers of the mask, thereby constituting Embodiment 4, Embodiment 5, Embodiment 6, Comparative Scheme 3, and Comparative Scheme 4 respectively.

[0100] Furthermore, for the above different embodiments and comparative schemes, the test results are shown in Table IV:

[0101]

[0102]

[0103] Specific principle analysis: If the fiber diameter of the melt-blown nonwoven fabric 21 is large, its pore size will be large, and the physical barrier effect will be weak (even if there is an electrostatic adsorption effect caused by electret, it is necessary to have a physical barrier effect to cooperate to achieve the best filtration efficiency). At this time, if the fiber diameter of the electrospun nanofiber cloth 22 used in combination is not considered, or the fiber diameter of the electrospun nanofiber cloth 22 is also large, such as in Comparative Scheme 3, the filtration device formed by the combination of the two will not meet the standard in terms of filtration efficiency, and the effect of such a combination will be far less than expected; while if specifically, the fiber diameter of the electrospun nanofiber cloth 22 used in combination is matched with the fiber diameter of the melt-blown nonwoven fabric 21 to obtain the fiber diameter of the electrospun nanofiber cloth 22, the defect of the melt-blown nonwoven fabric 21 in physical barrier can be compensated.

[0104] On the contrary, if the fiber diameters of the melt-blown nonwoven fabrics 21 are all small, such as in Comparative Scheme 4, the pore sizes will all be small, and the physical barrier effect will be relatively ideal. At this time, if the fiber diameter of the electrospun nanofiber cloth 22 used in combination is not considered, or the diameter of the electrospun nanofiber cloth 22 is also small, the breathing resistance after the two are combined will be too large, resulting in a serious decline in application value. Only by matching the fiber diameter of the electrospun nanofiber cloth 22 used in combination with the fiber diameter of the melt-blown nonwoven fabric 21 to obtain the fiber diameter of the electrospun nanofiber cloth 22, can the breathing resistance be improved to the greatest extent while achieving an increase in filtration efficiency.

[0105] It can be seen from Table III and Table IV that by comparing Examples 4 to 6 and matching the fiber diameter of the electrospun nanofiber cloth 22 used in combination with the fiber diameter of the melt-blown non-woven fabric 21, the filtration effect can be improved on the premise of ensuring air permeability. In the above Table III and Table IV, by comparing with the national standard GB / T 32610-2016 for daily protective masks, it can be clearly seen that Examples 4 to 6 show stable performance in terms of the filtration efficiency of saline aerosol and the saline filtration resistance, and the exhalation resistance and inhalation resistance are significantly lower than the above standard. On the premise of ensuring air permeability, the filtration effect is improved. If the optimal combination is selected, the effect of Example 6 is more balanced and can be used as the optimal combination.

[0106] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A filtering device with an electrospun nanofiber cloth, characterized in that, it includes: An electrospun nanofiber cloth; A melt-blown non-woven fabric, which is arranged on one side of the electrospun nanofiber cloth and forms a filtering structure with two or more layers with the electrospun nanofiber cloth; The relationship between the fiber diameters of the electrospun nanofiber cloth and the melt-blown non-woven fabric is inversely correlated, so that when the fiber diameter of the melt-blown non-woven fabric increases, the fiber diameter of the electrospun nanofiber cloth decreases; Set the filtration efficiency percentage of the melt-blown non-woven fabric for particles with a particle size of 0.02 - 10 μm as M, and set the filtration efficiency percentage of the electrospun nanofiber cloth for particles with a particle size of 0.02 - 10 μm as N; then it satisfies: M / N = 1.05 - 1.6, M is 80 - 96%, and N is 70 - 93%; The relationship between the fiber diameters of the electrospun nanofiber cloth and the melt-blown non-woven fabric satisfies the following formula: y = 0.5 / x, or x = y 2 -10.6y + 6.05; x is the fiber diameter of the melt-blown non-woven fabric; y is the fiber diameter of the electrospun nanofiber cloth; The grammage of the melt-blown non-woven fabric is: 10 - 40; The grammage of the electrospun nanofiber cloth is: 0.05 - 0.

5.

2. A filtering device with an electrospun nanofiber cloth according to claim 1, characterized in that, The fiber diameter of the melt-blown non-woven fabric is 1 - 5 μm; The fiber diameter of the electrospun nanofiber cloth is 0.1 - 0.5 μm.

3. A filtering device with an electrospun nanofiber cloth according to claim 1, characterized in that, The fiber diameter of the melt-blown non-woven fabric is 5 μm; The fiber diameter of the electrospun nanofiber cloth is 0.1 μm; Or: The fiber diameter of the melt-blown non-woven fabric is 1 μm; The fiber diameter of the electrospun nanofiber cloth is 0.5 μm.

4. A filtering device with an electrospun nanofiber cloth according to claim 1, characterized in that, The porosity of the electrospun nanofiber cloth is 1.10 - 1.29 times that of the melt-blown non-woven fabric, and the porosity of the melt-blown non-woven fabric is 70 - 90%.

5. A mask with an electrospun nanofiber cloth, characterized in that, it includes: A mask body, including an inner layer and an outer layer, and the inner layer is used to fit the user's face; The filtering device according to any one of claims 1 - 4, which is arranged between the inner layer and the outer layer; The melt-blown non-woven fabric is arranged on one side of the electrospun nanofiber cloth to support the electrospun nanofiber cloth.

6. A mask with an electrospun nanofiber cloth according to claim 5, characterized in that, The inner layer includes a non-woven fabric; And / or, the outer layer includes a non-woven fabric.

7. A mask with an electrospun nanofiber cloth according to claim 5, characterized in that, It further includes a strap: The strap is used to hold the mask body on the user's face.

8. A mask with an electrospun nanofiber cloth according to claim 7, characterized in that: The strap includes an ear-hook type, a tie type or a head-loop type.

9. A mask with an electrospun nanofiber cloth according to claim 5, wherein the mask body includes a planar or three-dimensional shape.

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