Air filter material and process for its production

Abstract

This invention relates to a high-efficiency, low-resistance air filter material and its manufacturing process. The filter material includes a filter layer and a breathable layer bonded to the filter layer. The breathable layer is polyurethane foam, and the filter layer is a fiber membrane formed by spinning with a spinning solution. The spinning solution includes the following components by weight: 20-25 parts of polymer, 80-120 parts of solvent, 0.5-1.5 parts of antibacterial particles, 0.5-0.9 parts of nanoparticles, and 2-3 parts of emulsifier. The polymer is one or a combination of polysulfone and polylactic acid, and the solvent is one or a combination of chloroform and dimethylformamide. By setting the filter material as a filter layer and a breathable layer, and setting a breathable roll in the breathable layer, the air permeability of the filter material is improved, facilitating the passage of air and thus reducing the resistance of the filter material. (2) By combining polyurethane foam with a fiber membrane, the filtration efficiency of the filter material is improved.

Description

Technical Field

[0001] This invention relates to the field of air filter material production technology, specifically to an air filter material and its production process. Background Technology

[0002] As people pay increasing attention to air quality, the research and application of air filtration materials have also received widespread attention. Air filtration materials can remove pollutants from the air, such as odors, smoke, formaldehyde, dust, and pollen. The use of air filtration materials can improve air quality, protect people's health, and thus improve the quality of life.

[0003] Currently, with the increasing demands for air quality, the requirements for the filtration efficiency of air filter materials are also increasing. Filter materials prepared using traditional filter materials and traditional preparation methods have low filtration efficiency. If their filtration efficiency is increased, the filtration resistance will increase to a certain extent, making it difficult to meet the current high requirements for high efficiency and low resistance of air filter materials. Summary of the Invention

[0004] This invention provides an air filtration material and its manufacturing process to solve the above-mentioned problems.

[0005] The technical solution adopted in this invention is: an air filter material, which includes a filter layer and a breathable layer bonded to the filter layer, wherein the breathable layer is polyurethane foam and the filter layer is a fiber membrane formed by spinning with spinning solution.

[0006] Preferably, the spinning solution comprises the following components by weight: 20-25 parts of polymer, 80-120 parts of solvent, 0.5-1.5 parts of antibacterial particles, 0.5-0.9 parts of nanoparticles, and 2-3 parts of emulsifier.

[0007] Preferably, the polymer is one or a combination of polysulfone and polylactic acid, and the solvent is one or a combination of chloroform and dimethylformamide.

[0008] Preferably, the antibacterial particles are one or a combination of two of nano-silica and quaternary ammonium salts, and the nanoparticles are nano-sodium chloride or nano-sodium sulfate.

[0009] Preferably, the breathable layer includes spaced-apart breathable rolls, which are adhered to the upper surface of the filter layer. The breathable rolls have a spiral winding structure along their central axis. The breathable rolls are made of one or more of glass fiber, polyester fiber, softwood pulp, and cotton pulp. The surface of the breathable rolls is integrally formed with convex balls, which are made of the same material as the breathable rolls. Polyurethane foam is filled between two adjacent breathable rolls, and a polyurethane foam layer is also adhered to the top of the breathable rolls.

[0010] A manufacturing process for an air filter material, the manufacturing process comprising at least the following steps:

[0011] S1: Mix polyurethane composite material and polymeric TDI in a mass ratio of 1:(0.5-0.7), stir for 5-8 seconds, and then foam it in a constant temperature mold with plastic film for 5 minutes to obtain a polyurethane foam layer.

[0012] S2: Adhere the spirally wound breathable roll to the upper surface of the polyurethane foam layer, and take the polyurethane composite material and polymeric TDI again, mix them in a mass ratio of 1:(0.5-0.7), stir for 5-8 seconds and then lay it on top of the polyurethane foam layer with the breathable roll attached, with the top of the breathable roll touching the upper mold of the mold; foam at a constant temperature for 10 minutes and demold to remove the plastic film to obtain the breathable layer;

[0013] S3: Prepare the spinning solution by mixing the polymer, solvent, antibacterial particles, nanoparticles and emulsifier, stirring at 60°C for 3 hours and vacuum degassing for 5 hours to obtain the spinning solution.

[0014] S4: Using the breathable layer as the receiving material, the electrospinning machine sprays out the spinning liquid and adheres it to the surface of the breathable layer to prepare a filter layer.

[0015] S5: Place the filter material in water, ultrasonically vibrate for 5 minutes, and then dry it.

[0016] Preferably, the temperature of both the upper and lower molds of the thermostatic mold is 35-45℃.

[0017] Preferably, before electrospinning the surface of the breathable layer, the breathable layer is soaked in distilled water at a temperature of 25-35°C for 10-25 minutes and then dried in a drying oven at a temperature of 75-90°C for 2 hours.

[0018] Preferably, the DC voltage of the electrospinning machine is 10-30kV, the extrusion rate of the electrospinning solution is 0.5-2.0ml / h, the receiving distance is 5-28cm, and the electrospinning time is 5-20min.

[0019] Preferably, the electrospinning machine has a spinning time of 20 minutes. During the first 0-5 minutes of spinning, the DC voltage of the electrospinning machine is 10kV and the receiving distance is 5cm. During the first 5-15 minutes, the DC voltage of the electrospinning machine is 20kV and the receiving distance is 15cm. During the first 15-20 minutes, the DC voltage of the electrospinning machine is 30kV and the receiving distance is 25cm.

[0020] Compared with the prior art, the present invention has the following advantages: (1) By setting the filter material as a filter layer and a breathable layer, and setting a breathable roll in the breathable layer, the breathability of the filter material is improved, and the air passes through easily, thereby reducing the resistance of the filter material; (2) By combining polyurethane foam with fiber membrane, the filtration efficiency of the filter material is improved; (3) The DC voltage of the electrospinning machine is adjusted from small to large, and the receiving distance is adjusted from small to large. The larger the DC voltage, the smaller the fiber diameter formed. The larger the receiving distance, the smaller the fiber diameter formed. This makes the fiber diameter of the filter layer decrease from near the breathable layer to far away from the breathable layer. That is to say, the fiber diameter of the filter layer decreases in sequence, thereby improving its filtration efficiency; (4) Antibacterial particles are added to the spinning solution of the filter layer, so that the filter layer has certain antibacterial properties and gives the filter material more functionality; (5) The filter material is soaked in water and subjected to ultrasonic vibration, so that the water-soluble nanoparticles dissolve in the water, thereby increasing the density of the filter layer of the filter material and reducing the filtration resistance of the filter layer. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the air filter material of the present invention. Detailed Implementation

[0022] To better illustrate the present invention, it will now be further described in conjunction with examples.

[0023] An air filtration material includes a filter layer 4 and a breathable layer bonded to the filter layer 4. The breathable layer is polyurethane foam, and the filter layer 4 is a fiber membrane formed by spinning with a spinning solution. Preferably, the spinning solution comprises the following components by weight: 20-25 parts of polymer, 80-120 parts of solvent, 0.5-1.5 parts of antibacterial particles, 0.5-0.9 parts of nanoparticles, and 2-3 parts of emulsifier.

[0024] Preferably, the polymer is one or a combination of polysulfone and polylactic acid, and the solvent is one or a combination of chloroform and dimethylformamide.

[0025] Preferably, the antibacterial particles are one or a combination of two of nano-silica and quaternary ammonium salts, and the nanoparticles are nano-sodium chloride or nano-sodium sulfate.

[0026] Preferably, the breathable layer includes spaced-apart breathable rolls 3, which are adhered to the upper surface of the filter layer 4. The breathable rolls 3 have a spiral winding structure along their central axis and are made of one or more of glass fiber, polyester fiber, softwood pulp, and cotton pulp. The surface of each breathable roll 3 has integrally formed raised spheres made of the same material as the breathable roll 3. Polyurethane foam is filled between adjacent breathable rolls 3, and a polyurethane foam layer 1 is also adhered to the top of each breathable roll 3. Therefore, the filter material includes a polyurethane foam layer 1. A low-resistance layer 2 is provided at the bottom of the polyurethane foam layer 1. The low-resistance layer 2 includes the breathable rolls 3 and the polyurethane foam. The breathable rolls 3 are bonded to the polyurethane foam layer 1, and the filter layer 4 is bonded to the low-resistance layer 2. The thickness ratio of the polyurethane foam layer 1, the low-resistance layer 2, and the filter layer 4 is 1:1.4:1.5. The diameter of the breathable rolls is 1 cm, and the area occupied by the polyurethane foam in the cross-section of the low-resistance layer is 50%.

[0027] A manufacturing process for an air filter material, the manufacturing process comprising at least the following steps:

[0028] S1: Mix the polyurethane blend and polymeric TDI at a mass ratio of 1:(0.5-0.7), stir for 5-8 seconds, and then foam the mixture in a constant-temperature mold with a plastic film for 5 minutes to obtain a polyurethane foam layer. The polyurethane blend consists of 100 parts polyether polyol, 0.5 parts ethylene glycol, 2 parts polyalkylene oxide potassium siloxane copolymer, 5 parts n-pentane, 0.5 parts triethylenediamine, 0.2 parts stannous octoate, 1 part 2-tert-butyl-4-ethylphenol, and 2 parts cell opener. The polyether polyol includes bifunctional and trifunctional polyols in a mass ratio of 2:3. The polymeric TDI was purchased from Wanhua Chemical Group. The surface density of the polyurethane foam formed by the polyurethane blend and polymeric TDI is 58-61 kg / cm³. 3 The polyurethane blends and polymeric TDI used in Examples 1-3 and each comparative example are the same as those described above;

[0029] S2: Adhere the spirally wound breathable roll to the upper surface of the polyurethane foam layer, and take the polyurethane composite material and polymeric TDI again, mix them in a mass ratio of 1:(0.5-0.7), stir for 5-8 seconds and then lay it on top of the polyurethane foam layer with the breathable roll attached, with the top of the breathable roll touching the upper mold of the mold; foam at a constant temperature for 10 minutes and demold to remove the plastic film to obtain the breathable layer;

[0030] S3: Prepare the spinning solution by mixing the polymer, solvent, antibacterial particles, nanoparticles and emulsifier, stirring at 60°C for 3 hours and vacuum degassing for 5 hours to obtain the spinning solution.

[0031] S4: Using the breathable layer as the receiving material, the electrospinning machine sprays out the spinning liquid and adheres it to the surface of the breathable layer to prepare a filter layer.

[0032] S5: Place the filter material in water, ultrasonically vibrate for 5 minutes, and then dry it.

[0033] Preferably, the temperature of both the upper and lower molds of the thermostatic mold is 35-45℃.

[0034] Preferably, before electrospinning the surface of the breathable layer, the breathable layer is soaked in distilled water at a temperature of 25-35°C for 10-25 minutes and then dried in a drying oven at a temperature of 75-90°C for 2 hours.

[0035] Preferably, the DC voltage of the electrospinning machine is 10-30kV, the extrusion rate of the electrospinning solution is 0.5-2.0ml / h, the receiving distance is 5-28cm, and the electrospinning time is 5-20min.

[0036] Preferably, the electrospinning machine has a spinning time of 20 minutes. During the first 0-5 minutes of spinning, the DC voltage of the electrospinning machine is 10kV and the receiving distance is 5cm. During the first 5-15 minutes, the DC voltage of the electrospinning machine is 20kV and the receiving distance is 15cm. During the first 15-20 minutes, the DC voltage of the electrospinning machine is 30kV and the receiving distance is 25cm.

[0037] Example 1

[0038] An air filtration material includes a filter layer and a breathable layer bonded to the filter layer. The breathable layer is polyurethane foam and includes spaced-apart breathable rolls adhered to the upper surface of the filter layer. The breathable rolls have a spiral winding structure along their central axis and are made of glass fiber, polyester fiber, softwood pulp, and cotton pulp, with a weight ratio of softwood pulp, polyester fiber, glass fiber, and cotton pulp of 5:0.5:0.4:0.3. The surface of the breathable rolls has integrally formed convex spheres made of the same material as the breathable rolls. Polyurethane foam is filled between two adjacent breathable rolls. The breathable rolls and the filled polyurethane foam are referred to as a low-resistance layer. A polyurethane foam layer is disposed on top of the low-resistance layer. The filter layer is a fiber membrane formed by spinning with spinning solution. The spinning solution comprises the following components by weight: 20 parts polymer, 120 parts solvent, 0.5 parts antibacterial particles, 0.9 parts nanoparticles, and 2 parts emulsifier; the polymer is a mixture of polysulfone and polylactic acid in a 1:1 mass ratio, the solvent is a mixture of chloroform and dimethylformamide in a 2:1 mass ratio; the antibacterial particles are a mixture of nano-silica and quaternary ammonium salt in a 1:0.4 mass ratio, the nanoparticles are a mixture of nano-sodium chloride and nano-sodium sulfate in a 2:1 mass ratio, the thickness ratio of the polyurethane foam layer, the low-resistance layer, and the filter layer is 1:1.4:1.5, the diameter of the breathable roll is 1 cm, and the area occupied by the polyurethane foam in the cross-section of the low-resistance layer is 50%.

[0039] A manufacturing process for an air filter material, the manufacturing process comprising at least the following steps:

[0040] S1: Mix polyurethane composite material and polymeric TDI at a mass ratio of 1:0.7, stir for 5 seconds, and then foam it in a constant temperature mold with plastic film for 5 minutes to obtain a polyurethane foam layer. The temperature of the upper and lower molds of the constant temperature mold is 45℃.

[0041] S2: The spirally wound breathable roll is bonded to the upper surface of the polyurethane foam layer. Polyurethane composite material and polymeric TDI are taken again and mixed in a mass ratio of 1:0.7. After stirring for 5 seconds, it is laid on top of the polyurethane foam layer with the breathable roll bonded on it. The top of the breathable roll is in contact with the upper mold of the mold. The foam is kept at a constant temperature for 10 minutes and then demolded and the plastic film is removed to obtain the breathable layer. The breathable roll is prepared by mixing various fibers and using existing pulp preparation technology. This is existing technology and will not be described in detail here.

[0042] S3: Soak the breathable layer in distilled water at 35℃ for 10 minutes, and then dry it in a drying oven at 90℃ for 2 hours to obtain the post-treated breathable layer.

[0043] S4: Prepare the spinning solution by mixing the polymer, solvent, antibacterial particles, nanoparticles and emulsifier, stirring at 60°C for 3 hours and vacuum degassing for 5 hours to obtain the spinning solution.

[0044] S5: Using the breathable layer as the receiving material, the electrospinning machine sprays out the spinning liquid and adheres it to the surface of the breathable layer to prepare a filter layer. The spinning time of the electrospinning machine is 20 min. During the first 0-5 min of spinning, the DC voltage of the electrospinning machine is 10 kV and the receiving distance is 5 cm. During the first 5-15 min of spinning, the DC voltage of the electrospinning machine is 20 kV and the receiving distance is 15 cm. During the first 15-20 min of spinning, the DC voltage of the electrospinning machine is 30 kV and the receiving distance is 25 cm.

[0045] S6: Place the filter material in water, ultrasonically vibrate for 5 minutes, and then dry it.

[0046] Example 2

[0047] An air filtration material includes a filter layer and a breathable layer bonded to the filter layer. The thickness ratio of the breathable layer to the filter layer is 1:1.5. The breathable layer is polyurethane foam and includes spaced-apart breathable rolls adhered to the upper surface of the filter layer. The breathable rolls have a spiral winding structure along their central axis. The breathable rolls are made of glass fiber, polyester fiber, softwood pulp, and cotton pulp, with a weight ratio of softwood pulp, polyester fiber, glass fiber, and cotton pulp of 5:0.5:0.4:0.3. The surface of the breathable rolls has integrally formed convex spheres made of the same material as the breathable rolls. Polyurethane foam is filled between two adjacent breathable rolls. The breathable rolls and the filled polyurethane foam are referred to as a low-resistance layer. A polyurethane foam layer is disposed on top of the low-resistance layer. The filter layer is a fiber membrane formed by spinning with spinning solution. The spinning solution comprises the following components by weight: 25 parts polymer, 80 parts solvent, 1.5 parts antibacterial particles, 0.5 parts nanoparticles, and 3 parts emulsifier. The polymer is a mixture of polysulfone and polylactic acid in a 1:1 mass ratio; the solvent is a mixture of chloroform and dimethylformamide in a 2:1 mass ratio; the antibacterial particles are a mixture of nano-silica and quaternary ammonium salt in a 1:0.4 mass ratio; and the nanoparticles are a mixture of nano-sodium chloride and nano-sodium sulfate in a 2:1 mass ratio. The thickness ratio of the polyurethane foam layer, the low-resistance layer, and the filter layer is 1:1.4:1.5. The diameter of the breathable roll is 1 cm, and the area occupied by the polyurethane foam in the cross-section of the low-resistance layer is 50%.

[0048] A manufacturing process for an air filter material, the manufacturing process comprising at least the following steps:

[0049] S1: Mix polyurethane composite material and polymeric TDI at a mass ratio of 1:0.5, stir for 8 seconds, and then foam it in a constant temperature mold with plastic film for 5 minutes to obtain a polyurethane foam layer. The temperature of the upper and lower molds of the constant temperature mold is 35℃.

[0050] S2: The spirally wound breathable roll is bonded to the upper surface of the polyurethane foam layer. Polyurethane composite material and polymeric TDI are taken again and mixed in a mass ratio of 1:0.5. After stirring for 8 seconds, it is laid on top of the polyurethane foam layer with the breathable roll bonded on it. The top of the breathable roll is in contact with the upper mold of the mold. The foam is kept at a constant temperature for 10 minutes and then demolded and the plastic film is removed to obtain the breathable layer. The breathable roll is prepared by mixing various fibers and using existing pulp preparation technology. This is existing technology and will not be described in detail here.

[0051] S3: Soak the breathable layer in distilled water at 25°C for 25 minutes, and then dry it in a drying oven at 75°C for 2 hours to obtain the post-treated breathable layer.

[0052] S4: Prepare the spinning solution by mixing the polymer, solvent, antibacterial particles, nanoparticles and emulsifier, stirring at 60°C for 3 hours and vacuum degassing for 5 hours to obtain the spinning solution.

[0053] S5: Using the breathable layer as the receiving material, the electrospinning machine sprays out the spinning liquid and adheres it to the surface of the breathable layer to prepare a filter layer. The spinning time of the electrospinning machine is 20 min. During the first 0-5 min of spinning, the DC voltage of the electrospinning machine is 10 kV and the receiving distance is 5 cm. During the first 5-15 min of spinning, the DC voltage of the electrospinning machine is 20 kV and the receiving distance is 15 cm. During the first 15-20 min of spinning, the DC voltage of the electrospinning machine is 30 kV and the receiving distance is 25 cm.

[0054] S6: Place the filter material in water, ultrasonically vibrate for 5 minutes, and then dry it.

[0055] Example 3

[0056] An air filtration material includes a filter layer and a breathable layer bonded to the filter layer. The thickness ratio of the breathable layer to the filter layer is 1:1.5. The breathable layer is polyurethane foam and includes spaced-apart breathable rolls adhered to the upper surface of the filter layer. The breathable rolls have a spiral winding structure along their central axis. The breathable rolls are made of glass fiber, polyester fiber, softwood pulp, and cotton pulp, with a weight ratio of softwood pulp, polyester fiber, glass fiber, and cotton pulp of 5:0.5:0.4:0.3. The surface of the breathable rolls has integrally formed convex spheres made of the same material as the breathable rolls. Polyurethane foam is filled between two adjacent breathable rolls. The breathable rolls and the filled polyurethane foam are referred to as a low-resistance layer. A polyurethane foam layer is disposed on top of the low-resistance layer. The filter layer is a fiber membrane formed by spinning with spinning solution. The spinning solution comprises the following components by weight: 22 parts polymer, 100 parts solvent, 1.0 part antibacterial particles, 0.8 parts nanoparticles, and 2.5 parts emulsifier. The polymer is a mixture of polysulfone and polylactic acid in a 1:1 mass ratio; the solvent is a mixture of chloroform and dimethylformamide in a 2:1 mass ratio; the antibacterial particles are a mixture of nano-silica and quaternary ammonium salt in a 1:0.4 mass ratio; and the nanoparticles are a mixture of nano-sodium chloride and nano-sodium sulfate in a 2:1 mass ratio. The thickness ratio of the polyurethane foam layer, the low-resistance layer, and the filter layer is 1:1.4:1.5. The diameter of the breathable roll is 1 cm, and the area occupied by the polyurethane foam in the cross-section of the low-resistance layer is 50%.

[0057] A manufacturing process for an air filter material, the manufacturing process comprising at least the following steps:

[0058] S1: Mix polyurethane composite material and polymeric TDI at a mass ratio of 1:0.6, stir for 6 seconds, and then foam it in a constant temperature mold with plastic film for 5 minutes to obtain a polyurethane foam layer. The temperature of the upper and lower molds of the constant temperature mold is 40℃.

[0059] S2: The spirally wound breathable roll is bonded to the upper surface of the polyurethane foam layer. Polyurethane composite material and polymeric TDI are taken again and mixed in a mass ratio of 1:0.6. After stirring for 6 seconds, it is laid on top of the polyurethane foam layer with the breathable roll bonded on it. The top of the breathable roll is in contact with the upper mold of the mold. The foam is kept at a constant temperature for 10 minutes and then demolded and the plastic film is removed to obtain the breathable layer. The breathable roll is prepared by mixing various fibers and using existing pulp preparation technology. This is existing technology and will not be described in detail here.

[0060] S3: Soak the breathable layer in distilled water at 30℃ for 20 minutes, and then dry it in a drying oven at 80℃ for 2 hours to obtain the post-treated breathable layer.

[0061] S4: Prepare the spinning solution by mixing the polymer, solvent, antibacterial particles, nanoparticles and emulsifier, stirring at 60°C for 3 hours and vacuum degassing for 5 hours to obtain the spinning solution.

[0062] S5: Using the breathable layer as the receiving material, the electrospinning machine sprays out the spinning liquid and adheres it to the surface of the breathable layer to prepare a filter layer. The spinning time of the electrospinning machine is 20 min. During the first 0-5 min of spinning, the DC voltage of the electrospinning machine is 10 kV and the receiving distance is 5 cm. During the first 5-15 min of spinning, the DC voltage of the electrospinning machine is 20 kV and the receiving distance is 15 cm. During the first 15-20 min of spinning, the DC voltage of the electrospinning machine is 30 kV and the receiving distance is 25 cm.

[0063] S6: Place the filter material in water, ultrasonically vibrate for 5 minutes, and then dry it.

[0064] Comparative Example 1

[0065] The difference from Example 3 is that this filter material does not contain breathable rolls, and the low-resistance layers are all polyurethane foam.

[0066] Comparative Example 2

[0067] The difference from Example 3 is that in step S5, the electrospinning machine spins for 20 minutes, and the DC voltage is always 10kV during these 20 minutes.

[0068] Comparative Example 3

[0069] The difference from Example 3 is that in step S5, the electrospinning machine spins for 20 minutes, and the DC voltage is always 30kV during these 20 minutes.

[0070] Comparative Example 4

[0071] The difference from Example 3 is that step S6 is not performed, that is, the filter material is not subjected to water immersion and ultrasonic vibration treatment.

[0072] According to ISO 5011 standard, the products prepared in Examples 1-3 and Comparative Examples 1-3 were subjected to performance tests. The test medium was A2 fine ash, the wind speed was 10.3 cm / s, and the DOP efficiency was tested at the same time. The test equipment was TSI8130A. The results are shown in Table 1.

[0073] Table 1

[0074] 0.3μm filtration efficiency % Initial resistance Pa Example 1 98.421 2.3 Example 2 99.173 2.4 Example 3 99.664 2.1 Comparative Example 1 99.679 6.9 Comparative Example 2 91.372 1.8 Comparative Example 3 99.781 10.3 Comparative Example 4 99.653 5.8

[0075] In addition, the antibacterial properties of the filter material were tested in accordance with GB / T20944.2-2007. The antibacterial rates of Escherichia coli, Staphylococcus aureus and Candida albicans in Examples 1-3 all reached over 99%.

[0076] The above description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several changes and improvements without departing from the overall concept of the present invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. An air filter material, characterized in that: The filter material includes a filter layer and a breathable layer bonded to the filter layer. The breathable layer is polyurethane foam, and the filter layer is a fiber membrane formed after spinning with spinning solution. The breathable layer includes spaced-apart breathable rolls adhered to the upper surface of the filter layer. Each breathable roll has a spiral winding structure along its central axis. The breathable roll is made of one or more of the following: glass fiber, polyester fiber, softwood pulp, and cotton pulp. The surface of each breathable roll is integrally formed with raised spheres made of the same material as the breathable roll. Polyurethane foam is filled between adjacent breathable rolls, and a polyurethane foam layer is also adhered to the top of each breathable roll. The spinning solution comprises the following components by weight: 20-25 parts polymer, 80-120 parts solvent, 0.5-1.5 parts antibacterial particles, 0.5-0.9 parts nanoparticles, and 2-3 parts emulsifier. The polymer is one or a combination of polysulfone and polylactic acid.

2. The air filter material according to claim 1, characterized in that: The solvent is one or a combination of two of chloroform and dimethylformamide.

3. The air filter material according to claim 1, characterized in that: The antibacterial particles are one or a combination of two of nano-silica and quaternary ammonium salts, and the nanoparticles are nano-sodium chloride and nano-sodium sulfate.

4. The production process of an air filter material according to any one of claims 1-3, characterized in that: The production process includes at least the following steps: S1: Mix polyurethane composite material and polymeric TDI in a mass ratio of 1:(0.5-0.7), stir for 5-8 seconds, and then foam it in a constant temperature mold with plastic film for 5 minutes to obtain a polyurethane foam layer. S2: Adhere the spirally wound breathable roll to the upper surface of the polyurethane foam layer, and take the polyurethane composite material and polymeric TDI again, mix them in a mass ratio of 1:(0.5-0.7), stir for 5-8 seconds and then lay it on top of the polyurethane foam layer with the breathable roll attached, with the top of the breathable roll touching the upper mold of the mold; foam at a constant temperature for 10 minutes and demold to remove the plastic film to obtain the breathable layer; S3: Prepare the spinning solution by mixing the polymer, solvent, antibacterial particles, nanoparticles and emulsifier, stirring at 60°C for 3 hours and vacuum degassing for 5 hours to obtain the spinning solution. S4: Using the breathable layer as the receiving material, the electrospinning machine sprays out the spinning liquid and adheres it to the surface of the breathable layer to prepare a filter layer. S5: Place the filter material in water, ultrasonically vibrate for 5 minutes, and then dry it. The polyurethane composition consists of 100 parts polyether polyol, 0.5 parts ethylene glycol, 2 parts polyalkylene oxide potassium siloxane copolymer, 5 parts n-pentane, 0.5 parts triethylenediamine, 0.2 parts stannous octoate, 1 part 2-tert-butyl-4-ethylphenol, and 2 parts cell opener. The polyether polyol includes bifunctional and trifunctional polyols in a mass ratio of 2:

3.

5. The production process of an air filter material according to claim 4, characterized in that: The temperature of both the upper and lower molds of the thermostatic mold is 35-45℃.

6. The production process of an air filter material according to claim 5, characterized in that: Before electrospinning the surface of the breathable layer, immerse the breathable layer in distilled water at a temperature of 25-35℃ for 10-25 minutes, and then dry it in a drying oven at a temperature of 75-90℃ for 2 hours.

7. The production process of an air filter material according to claim 5, characterized in that: The DC voltage of the electrospinning machine is 10-30kV, the extrusion rate of the electrospinning solution is 0.5-2.0ml / h, the receiving distance is 5-28cm, and the electrospinning time is 5-20min.

8. The production process of an air filter material according to claim 7, characterized in that: The electrospinning machine has a spinning time of 20 minutes. During the first 5 minutes of spinning, the DC voltage of the electrospinning machine is 10kV and the receiving distance is 5cm. During the first 15 minutes, the DC voltage of the electrospinning machine is 20kV and the receiving distance is 15cm. During the first 20 minutes, the DC voltage of the electrospinning machine is 30kV and the receiving distance is 25cm.

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