KR20210155719A - Nano fiber filter and its manufacturing method - Google Patents

Abstract

The present invention relates to a nanofiber filter and a manufacturing method thereof, which can secure antimicrobial, breathability, and visibility and obtain an excellent collection efficiency of dust including infectious pathogens, etc., and can be adhered to an eco-friendly aqueous adhesive to be applied to various objects including a human body, in which the manufacturing method includes: a) introducing a first mesh layer into an electrical radiation device; b) electrospinning a polyvinylidene fluoride (PVDF) solution on the first mesh layer to form a nanofiber layer; c) initially coating an upper surface of the nanofiber layer and a lower surface of a second mesh layer with an eco-friendly aqueous adhesive using a roller; d) winding the nanofiber layer and the second mesh layer in a branch or a drum, respectively, and leave them for 2 to 6 hours to infiltrate the initially coated aqueous adhesive to penetrate the nanofiber layer and the second mesh layer; e) finally coating an upper surface of the nanofiber layer with the eco-friendly aqueous adhesive using the roller; f) passing the first mesh layer, the nanofiber layer that is finally coated with the eco-friendly aqueous adhesive, and the second mesh layer through a portion between upper and lower rollers heated at a temperature of 60 to 90℃, to thermally compressing and bonding the first mesh layer, the nanofiber layer, and the second mesh layer; and g) completely drying for 48 to 96 hours at room temperature. The manufactured nanofiber filter manufactured by the manufacturing method is included.

Description

Nano fiber filter and its manufacturing method

The present invention relates to a nanofiber filter and a method for manufacturing the same, and more particularly, by adhering a nanofiber layer and a nanofiber layer protective mesh layer with an eco-friendly water-based adhesive, it has excellent antibacterial properties, breathability and visibility, and is widely applied to various objects including the human body It is designed to achieve excellent collection efficiency of various dusts including infectious pathogens.

In general, the nanofiber (Nano Fiber) refers to a microfiber having a diameter of only several tens to several hundreds of nanometers, and is produced by an electric field. That is, nanofibers apply a high-voltage electric field to the raw material polymer material to generate an electrical repulsive force inside the raw material polymer material. is manufactured and produced. At this time, the stronger the electric field, the finer the polymer material, which is the raw material, so that nanofibers having a fineness of 10 nm to 1,000 nm can be obtained.

On the other hand, a filter is a filtration device that filters out foreign substances in a fluid and is classified into a liquid filter and an air filter. In particular, an air filter is a biological particle such as particulates such as dust in the air, biological particles such as bacteria and mold, bacteria, and viruses, etc. It is used to remove harmful substances.

Conventional air filters made of simple non-woven fabric have advantages of a simple manufacturing process and low cost, so they are widely used in various applications. However, they have the disadvantage of low dust filtration efficiency. There is a problem in that the collection ability is reduced.

Among the disadvantages of the non-woven type air filter, an air filter using a non-woven fabric to which an electrostatic charge is added has been developed and used to supplement the fine dust collection efficiency. reduced, there is a problem that the dust collection efficiency is rapidly lowered. For example, the reduction of the dust collection efficiency due to the reduction of the electrostatic characteristics has several problems, such as a reduction in the dust collection efficiency of about 30% from the initial 99,97%.

Republic of Korea Patent Publication No. 10-1585506 (Title of the invention: PVDF nanofiber-based patterned flexible piezoelectric element using electrospinning method and manufacturing method thereof, 2016. 01. 15. Patent announcement) Republic of Korea Patent Publication No. 10-1079775 (Title of the invention: Electrically conductive nanofiber manufacturing method through electrospinning followed by electroless plating, 2011. 11. 03. Patent announcement)

The present invention adheres the nanofiber layer and the nanofiber layer protective mesh layer with an eco-friendly water-based adhesive to not only have excellent antibacterial properties, breathability and visibility, but also can be applied to various objects including the human body. An object of the present invention is to provide a nanofiber filter capable of obtaining efficiency and a method for manufacturing the same.

The nanofiber filter manufacturing method of an embodiment of the present invention includes: a) putting a first mesh layer into an electrospinning device; b) electrospinning a polyvinylidene fluoride (PVDF) solution on the first mesh layer to form a nanofiber layer step of; c) rough coating of an eco-friendly water-based adhesive on the upper surface of the nanofiber layer and the lower surface of the second mesh layer with a roller; d) winding the nanofiber layer and the second mesh layer on a paper tube or drum, respectively, and then leaving them at room temperature for 2 to 6 hours to permeate the water-based adhesive with the rough coating to permeate into the nanofiber layer and the second mesh layer; e) finishing coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer with a roller; f) thermocompression bonding and bonding by passing the first mesh layer and the nanofiber layer coated with the environmentally friendly water-based adhesive between the upper and lower rollers heated to a temperature of 60 to 90° C.; g) Complete drying for 48 to 96 hours at room temperature.

The nanofiber filter manufacturing method of another embodiment of the present invention comprises the steps of: a`) rough coating an eco-friendly water-based adhesive on the upper surface of the first mesh layer with a roller; b`) natural drying at room temperature so that the moisture content of the first mesh layer coated with the rough coating is maintained at 40-60%; c`) putting the first mesh layer into the electrospinning device; d`) forming a nanofiber layer by electrospinning a polyvinylidene fluoride (PVDF) solution on the first mesh layer; e`) coating the top surface of the nanofiber layer and the bottom surface of the second mesh layer with an eco-friendly water-based adhesive with a roller; f`) winding the nanofiber layer and the second mesh layer on a paper tube or drum, respectively, and leaving it at room temperature for 2 to 6 hours to permeate the water-based adhesive coated with the chaebol to permeate into the nanofiber layer and the second mesh layer; g`) finishing coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer with a roller; h`) passing the nanofiber layer and the second mesh layer between the upper and lower rollers heated to a temperature of 60 to 90° C., followed by thermocompression bonding and bonding; i`) Complete drying for 48 to 96 hours at room temperature to obtain a nanofiber filter.

Instead of completely drying at room temperature for 48 to 96 hours to obtain a nanofiber filter, heating and drying for 12 to 24 hours in a drying room at 60 to 90 ° C. and then completely drying at room temperature for 12 to 24 hours to obtain a nanofiber filter. .

The eco-friendly water-based adhesive includes 5 to 15% by weight of water, 10 to 22% by weight of an aqueous EVA copolymer, 65 to 75% by weight of an aqueous acrylic copolymer, and 2 to 5% by weight of a VOC reducing agent.

The water-based adhesive coating (application) amount may be 8 to 30 g/m 2 .

The glass transition temperature (Tg value) of the water-based adhesive may be -25 to 0 ℃.

It may further include 1 to 10% by weight of adipic dihydrazide (ADIPIC DIHYDRAZIDE) mixed in the water-based adhesive.

Further comprising 2 to 8% by weight of a water-repellent liquid mixed in the water-based adhesive, wherein the water-repellent liquid may be an eco-friendly fluorine-based water-repellent liquid of C6 or less or a silicone-based water-repellent liquid.

The glass transition temperature of the water-based adhesive may be -25 to 0° C., and the viscosity may be 300 to 800 cps.

It includes a nanofiber filter manufactured by at least any one or more manufacturing methods of the nanofiber filter manufacturing method.

Including a nanofiber filter manufactured by at least any one of the manufacturing methods of the nanofiber filter, the nanofiber layer is transparent white, and the transparency may be 70 to 90%.

The nanofiber filter manufactured by at least one manufacturing method of the nanofiber filter manufacturing method is any one of a mask, a hat, gloves, a dustproof suit, a protective suit, a dustproof net, an air purifier, an air filter for ventilation, an air filter for transportation, and an industrial filter can

The nanofiber filter includes a first net layer composed of a fibrous network of a predetermined mesh, a nanofiber layer electrospun and bonded with a polyvinylidene fluoride (PVDF) solution on the upper surface of the first net layer, and the nanofiber layer and a second mesh layer adhered to the upper surface and composed of a fibrous mesh of a predetermined mesh.

The nanofiber layer may have a basis weight of 0.05 to 0.5 gsm and air permeability of 80 to 150 cfm.

The first mesh layer may be 6,400 to 10,000 mesh, and the basis weight may be 15 to 30 gsm.

The second mesh layer may be 1,225 to 3,025 mesh, and the basis weight may be 40 to 55 gsm.

The color of the nanofiber layer may be transparent white, and the transparency may be 70 to 90%.

The amount of the aqueous adhesive coated on the first and second mesh layers and the nanofiber layer may be 8 to 30 g/m 2 .

The present invention has excellent visibility due to high transparency, fine dust viruses, etc. are filtered to obtain an excellent effect as a filter, and volatile organic compounds (VOC), formaldehyde, acetaldehyde, etc. are not detected. It has an effect that can be applied not only to articles (face masks, coatings), but also to various objects.

According to the present invention, nano-sized pores smaller than fine particles and larger than air are formed in the nanofiber layer 2, so dust, particulate harmful substances, mist, dust including fine dust, yellow sand, pollen, fine particles, etc. Dust), as well as various pathogens, bacteria, bacteria, and infectious agents such as viruses and/or droplets containing them, are effectively blocked.

In the present invention, the 'differential pressure', which is the pressure difference before and after passing through the nanofiber layer 2, is measured as 1.4, so it is very comfortable to breathe.

The present invention has excellent visibility and transmittance, so that it transmits about 70 to 80%, so that an applied object can be easily identified. For example, in the case of a face mask worn on the face, the entire face including the wearer's face can be checked, and the facial makeup expressed on the wearer's face (face) or the aesthetic or aesthetic feeling expressed on the face is naturally expressed to the outside. It has the effect of being able to show off your aesthetic sense to the people around you.

In addition, a typical MB filter (or HEPA filter) absorbs and collects fine dust in an electrostatic method, so it is weak to moisture or moisture, and there are problems such as deterioration and shrinkage when worn for a long time, but the nanofiber filter of the present invention is dense. Because the nano-scale fiber strands are entangled and filtered by a physical method that blocks dust, dust, viruses, etc., they are hardly affected by moisture or moisture, and in the safety test, various harmful components are not detected or less than the standard, so it can be used with confidence. can have an effect.

In the present invention, even if various dust, fine dust, various foreign substances, bacteria, bacteria, viruses, etc. adsorbed or adhered to the nanofiber layer 2 are adhered, it can be easily separated (desorbed) by rinsing with water, preferably running water. It has the effect that it can be used repeatedly.

The present invention has an effect that can be usefully used as a human body coating, such as a mask, hat, glove, dustproof suit, protective suit, etc., because the multi-layered nanofiber filter is well bonded by an aqueous adhesive harmless to the human body.

The present invention not only has excellent water repellency without a separate water repellent treatment, but also has the effect of doubling the water repellency by additionally applying a water repellent solution.

The present invention has the effect of blocking and killing bacteria, mold, bacteria, viruses, etc. in a short time, as well as not harmless to the human body because heavy metals and other harmful substances and formaldehyde harmful to the human body are not detected.

The present invention is a very useful invention that has the effect of preventing (preventing) the transmission of viruses, bacteria, bacteria, and pathogens caused by saliva or droplets as well as being recognized when applied as a face mask due to high transparency to be.

Figure 1: An exemplary configuration of the nanofiber filter of the present invention.
Figure 2: A flow chart of a method for manufacturing a nanofiber filter shown in an embodiment of the present invention.
Figure 3: A flow chart of a method for manufacturing a nanofiber filter shown in another embodiment of the present invention.
Figure 4: A scanning electron microscope image (228 magnification) of a state in which the nanofiber layer is formed on the first mesh layer in the present invention.
Figure 5: Scanning electron microscope image showing the nanofiber layer in the present invention (5,000 magnification).
6 : A scanning electron microscope image (10,000 magnification) showing the nanofiber layer in the present invention.
Figure 7: Blank photograph of strain 1 in the present invention antibacterial activity test.
Figure 8: A photograph of the test result of strain 1 in the antibacterial activity experiment of the present invention (18 hours elapsed).
Figure 9: Blank photograph of strain 2 in the present invention antibacterial activity test.
Figure 10: A photograph of the test result of strain 2 in the antimicrobial activity test of the present invention (18 hours elapsed).
Figure 11: A photograph showing the transmittance of the present invention nanofiber filter outdoors in sunlight.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the embodiments of the present invention, the same components in the drawings are denoted by the same reference numerals as much as possible, and detailed descriptions of related known configurations or functions are omitted so as not to obscure the gist of the present invention, and also in the accompanying drawings Matters expressed in may be different from the forms actually implemented in the drawings schematically for easy explanation of the embodiments of the present invention.

1 illustrates the layer structure of the nanofiber filter of the present invention, a first mesh layer 1 composed of a fiber mesh of a predetermined mesh, and polyvinylidene fluoride on the upper surface of the first mesh layer 2 A (PVDF: Polyvinylidene fluoride) solution includes a nanofiber layer 2 electrospun and bonded, and a second mesh layer 3 adhered to the upper surface of the nanofiber layer 2 and composed of a fibrous mesh of a predetermined mesh.

According to the present invention, nano-sized pores smaller than fine particles and larger than air are formed in the nanofiber layer 2, so dust, particulate harmful substances, mist, dust including fine dust, yellow sand, pollen, fine particles, etc. Dust) as well as various pathogens, bacteria, bacteria, and infectious agents such as viruses and/or droplets containing them are effectively blocked.

The first and second mesh layers 1 and 3 may be a woven mesh or a fiber mesh having a predetermined mesh. The first and second mesh layers (1) (3) are preferably woven with a weft and a warp, but may be a knitted fabric.

The first and second mesh layers (1) (3) are adhered or fixed to the upper and lower surfaces of the nanofiber layer (2) to sufficiently protect the nanofiber layer (2), and air permeability, visibility, durability, etc. are maintained.

In the above, the first mesh layer 1 input to the electrospinning device (not shown) is higher than the first mesh layer 3 so that the electrospinning and the nanofiber layer 2 are efficiently formed and the contact area is enlarged and uniformly fixed. The mesh is formed densely.

For example, the first mesh layer 1 may have 6,400 to 10,000 mesh and a basis weight of 15 to 30 gsm, and the second mesh layer 3 may have 1,225 to 3,025 mesh and a basis weight of 40 to 55 gsm.

The weft and warp yarns constituting the first and second mesh layers 1 and 3 are olefin-based polypropylene (PP), polyvinyl acrylate (PVA), polyacnilonitrile (PAN), and polylactic acid (PLA). ), polyelactide (PLLA), polyethersulfone (PES), polyamide (PA) and one main raw material selected from the group consisting of gelatin; Dimethylacetamide (DMAC), dimethyl fluorine (DMF), dimethyl sulfoxide (DMSO), chlorobenzene (CB), trichloroethanol (TCE), trifluoroethylene (TFE), tetrahydrofuran (THF), Methyl ethyl ketone (MEK), toluene (Toluene), xylene (Xylene), formic acid, acetic acid, one or more solvents selected from the group consisting of water; is manufactured by extrusion at a mixing ratio of 8-20 wt%: 92-80 wt%.

The amount (coating amount) of the aqueous adhesive to be coated on the first and second mesh layers (1) (3) and the nanofiber layer (2) is 8 to 30 g/m 2 . When the application amount of the water-based adhesive is less than 8 g/m2, the desired adhesive strength cannot be obtained, and when the application amount exceeds 30 g/m2, it is not only wasted, but also the nanofiber layer 2 and the nanocell are broken by an excessive amount (brittle) ), damage and/or destruction, which is undesirable.

The first mesh layer (1), the nanofiber layer (2) and the second mesh layer (3) are adhered to each other with an eco-friendly water-based adhesive that is harmless to the human body. The water-based adhesive has no odor and is safe and harmless to the human body by using an eco-friendly material that does not contain harmful substances.

2 is a view showing a method of manufacturing a nanofiber filter according to an embodiment of the present invention. After the first mesh layer 1 is put into the electrospinning device (step S1), polyvinylidene fluoride is placed on the first mesh layer 1 (PVDF) solution is electrospinning to form a nanofiber layer 2 (step S2), and an eco-friendly water-based adhesive is applied to the upper surface of the nanofiber layer 2 and the bottom surface of the second mesh layer 3 with a roller. first roll coating) (step S3), the nanofiber layer (2) and the second mesh layer (3) coated with an eco-friendly water-based adhesive are wound on a paper tube or drum, respectively, and then left at room temperature for 2 to 6 hours to make a first roll. coating) the water-based adhesive to penetrate sufficiently into the nanofiber layer 2 and the second mesh layer 3 (step S4), and the eco-friendly water-based adhesive is applied to the upper surface of the nanofiber layer 2 with a roller finish roll coating ) and (step S5), the first mesh layer (1) and the nanofiber layer (2) coated with an eco-friendly water-based adhesive finish and the second mesh layer (3) are passed between the upper and lower rollers that are heated to a temperature of 60 to 90 ° C. thermocompression bonding and bonding (step S6), and drying completely at room temperature for 48 to 96 hours to obtain a nanofiber filter (step S7).

Instead of completely drying at room temperature for 48 to 96 hours (step S7), the nanofiber filter can be obtained by heating and drying in a drying room at 60 to 90 ° C. for 12 to 24 hours and then completely drying at room temperature for 12 to 24 hours (step S8).

3 shows a method for manufacturing a nanofiber filter according to another embodiment of the present invention, by first roll coating an eco-friendly water-based adhesive on the upper surface of the first net layer 1 with a roller (step S11), and eco-friendly water-based adhesive The adhesive is dried naturally at room temperature so that the moisture content of the first mesh layer 1 with the rough coating is maintained at 40-60% (step S12), and the first mesh layer 1 is put into the electrospinning device (step S13), and the first Electrospinning a polyvinylidene fluoride (PVDF) solution on the mesh layer 1 to form the nanofiber layer 2 (step S14), the upper surface of the nanofiber layer 2 and the bottom surface of the second mesh layer 3 Secondary roll coating of the eco-friendly water-based adhesive with a roller (step S15), the nanofiber layer (2) and the second mesh layer (3) coated with the eco-friendly water-based adhesive are wound on a paper tube or drum, respectively, and then 2 to 6 Leave at room temperature for a period of time to allow the chaebol-coated water-based adhesive to permeate sufficiently into the nanofiber layer 2 and the second mesh layer 3 (step S16), and then finish the eco-friendly water-based adhesive on the upper surface of the nanofiber layer 2 with a roller After coating (finish roll coating) (step S17), the first mesh layer (1) and the nanofiber layer (2) and the second mesh layer (3) coated with the eco-friendly water-based adhesive are heated to a temperature of 60 to 90 ° C. It is passed between the upper and lower rollers for thermocompression bonding and bonding (step S18), and then completely dried at room temperature for 48 to 96 hours to obtain a nanofiber filter (step S19).

Instead of completely drying at room temperature for 48 to 96 hours (step S19), the nanofiber filter can be obtained by heating and drying in a drying room at 60 to 90 ° C. for 12 to 24 hours and then completely drying at room temperature for 12 to 24 hours (step S20).

The eco-friendly water-based adhesive is an eco-friendly hybrid adhesive containing a water-based ethylene vinyl acetate (EVA) copolymer and a water-based acrylic copolymer, which turns transparent after drying (or curing) and leaves no trace.

The eco-friendly water-based adhesive contains 5 to 15% by weight of water, 10 to 22% by weight of an aqueous EVA (ethylene vinyl acetate) copolymer, 65 to 75% by weight of an aqueous acrylic copolymer, and 2 to 5% by weight of a VOC reducing agent do.

The glass transition temperature of the eco-friendly water-based adhesive is -25 to 0° C., and the viscosity is 300 to 800 cps.

If the glass transition temperature is less than -25 ℃, there is a problem that the shape of the nanofiber filter can be easily deformed as the bendability (ductility) of the nanofiber filter is too soft. It is preferable to have a glass transition temperature of -25°C to 0°C, which is soft and has excellent adhesion, because rejection may occur.

The EVA copolymer (ethylene-vinyl acetate copolymer) is a polymer obtained by copolymerizing ethylene and a vinyl acetate monomer, and is also called an ethylene-vinyl acetate copolymer. As the content of vinyl acetate increases, the density increases, but the degree of crystallization decreases and flexibility increases. Low-content EVA is processed like ordinary low-density polyethylene and has excellent impact resistance (especially at low temperatures) and stress cracking resistance, so it is used for heavy packaging materials and adhesives for laminate films. 10-20% of EVA is used in applications such as foam molded products such as sandals and soles, agricultural films, and flexible vinyl chloride such as stretch films for business use. A high concentration of EVA is used as a raw material for adhesives.

The acrylic copolymer (acrylic resin) refers to a polymer from an ester such as acrylic acid or methacrylic acid. A typical example is a polymer of methyl methacrylate (methyl methacrylate), which is colorless and transparent and transmits light, especially ultraviolet rays, better than ordinary glass (refractive index 1.49). It does not discolor even when exposed outdoors, has good chemical resistance, and has good electrical insulation and water resistance.

The VOC reducing agent may be an aqueous solution containing 69 to 90% by weight of water, 4 to 12% by weight of thiourea, 1 to 4% by weight of urea, and 1 to 4% by weight of boric acid, It has the effect of adsorbing and deodorizing components such as volatile organic compounds (VOC) and formaldehyde, so it is harmless to the human body.

The thiourea (CH ₄ N ₂ S) is an organic compound composed of carbon, nitrogen, sulfur, hydrogen, etc., and is a colorless crystal, and has a structure in which an oxygen atom of urea is substituted with a sulfur atom, Also called carbamide. Thiourea has a molecular weight of 7312, a melting point of 180°C, and a specific gravity of 1405. It is soluble in water and ethanol, but almost insoluble in ether. The aqueous solution is neutral and has a bitter taste. When hydrolyzed with acid or alkali, it is decomposed into ammonia, hydrogen sulfide, and carbon dioxide, and when oxidized with potassium permanganate, it becomes urea, and the deodorization effect is excellent.

The urea (urea, 尿素) is _{an organic compound with the chemical formula CO(NH 2} ) _{2 It} is a colorless crystalline substance, and is a final product of protein metabolism in all mammals and some fish, including urea, carbamide, and diamond. Also called diaminomethanal, it has no color or odor and is a substance that produces columnar crystals, has a molecular weight of 60047, a melting point of 1327°C (1 atm), and a specific gravity of 1335. Since it is a highly polar substance, it is readily soluble in water and alcohol, but insoluble in ether.

The boric acid (boric acid, 硼酸) (H ₃ BO ₃ ) is an oxygen acid produced by hydration of boron oxide, and there are orthoboric acid, metaboric acid, tetraboric acid, and the like, and usually refers to orthoboric acid. Orthoboric acid is a raw material for borosilicate glass and ceramic glaze, and it also promotes the dissolution of injections. Orthoboric acid is colorless, transparent or flaky crystals with a white luster. It has no odor and has a unique taste. The melting point is 184~186℃, and the specific gravity is 149.

The nanofiber filter of the present invention removes volatile organic compounds (VOC), formaldehyde, acetaldehyde, miscellaneous odors, and can be used with confidence in any climatic conditions, and prevents the propagation of various molds and bacteria, and prevents bacteria, pathogens, bacteria, Viruses are killed in a short time.

The present invention may further include 1 to 10% by weight of adipic dihydrazide (ADH: ADIPIC DIHYDRAZIDE) mixed with the aqueous adhesive. The molecular structure of the adipic dihydrazide is as follows, and the molecule is composed of 14 hydrogen atoms, 6 carbon atoms, 4 nitrogen atoms, and 2 oxygen atoms, so that a total of 26 atoms is formed. Adipic dihydrazide molecule has a total of 25 chemical bonds, which are composed of 11 non-hydrogen bonds, 2 multiple bonds, 5 single bonds, 2 double bonds, and 2 N hydrazines. It greatly contributes to reducing the formaldehyde of the nanofiber filter coated with the water-based adhesive as it is mixed and liquefied.

The present invention may further include a water-repellent solution of 2 to 8% by weight mixed with the water-based adhesive. The water-repellent liquid is an eco-friendly fluorine-based water-repellent liquid of C6 or less or a silicone-based water-repellent liquid.

The polyvinylidene fluoride (PVDF) of the present invention has its own water-repellent function, but the water-repellent power of the nanofiber filter is doubled by further including the water-repellent solution.

The polyvinylidene fluoride (PVDF) is a ferroelectric material and has its own static electricity.

4 is an enlarged image of a state in which the nanofiber layer 2 is formed on the weft and warp yarns of the first mesh layer 1 using a scanning electron microscope at 228 times magnification, and FIG. 5 is the nanofiber layer 2 5,000 times It is an image taken at a magnification, and FIG. 6 is an image taken at a magnification of 10,000 times the nanofiber layer 2 .

6, it can be seen that the nanofiber yarns with diameters of 125.5 nm, 150.6 nm, 200.8 nm, and 251.0 nm and the surrounding nanofiber yarns are configured in the form of a web, and pores (nanocells) formed between the nanofiber yarns. ) is in the range of at least 50nm to 1㎛, and ventilation and respiration are achieved while the air enters and exits through the pores.

The nanofiber layer 2 has a basis weight of 0.05 to 0.5 gsm, and also has an air permeability of 80 to 150 cfm, so breathing is not burdensome or difficult.

The nanofiber yarn of the nanofiber layer 2 may have a diameter of 100 nm to 300 nm. When the diameter of the nanofiber yarn is larger than 300 nm, microfinement is not sufficient, the fiber surface area is lowered, and the collection efficiency as a filter material for a filter is lowered, so that it is difficult to remove fine dust, etc. There is a problem in that the pressure is lowered, the density is increased, the differential pressure is increased, the strength is decreased, and the production is difficult.

In the present invention, even if various dust, fine dust, various foreign substances, bacteria, bacteria, viruses, etc. adsorbed or adhered to the nanofiber layer 2 are adhered, it can be easily separated (desorbed) by rinsing with water, preferably running water. It can be used repeatedly.

The color of the polyvinylidene fluoride (PVDF) is transparent white (white) or high transparency white (white), so that it is possible to identify objects located in the rear due to high transparency, that is, visibility.

Although the first mesh layer (1) and the second mesh layer (3) of the nanofiber filter of the present invention are translucent or opaque, the color of polyvinylidene fluoride (PVDF), which is a constituent material of the nanofiber layer (2), is transparent or white with high transparency It is (white) and has high visibility, so you can check the objects located in the back.

The nanofiber filter of the present invention has a transparency of about 70-90%, and has excellent visibility as shown in FIG. 11, so that 70-90% of various objects, shapes, or colors located at the rear are transmitted, so it is differentiated from the existing opaque face mask, etc. , when the face mask is worn on the face, it can also be seen through the wearer's face, and the entire face including the wearer's face can be seen, so that the aesthetics or aesthetic feelings expressed in facial makeup or the face are directly expressed to the outside. It works.

In addition, when applied to a face mask and worn, it naturally reveals the face, not for criminal or face-covering purposes. It can be usefully used as various filters, masks, coatings, etc. to remove biologically transmitted (MERS/SARS/Coronavirus Infectious Disease-19 (COVID-19), etc.) or harmful substances such as viruses, droplets, etc.

The transparency of the nanofiber filter may be changed according to the size and number of nanopores included in the mesh of the first and second mesh layers 1 and 3 and the nanofiber layer 2 .

In addition, the colors of the first mesh layer 1 and the second mesh layer 3 may implement various colors by selecting various colorants (pigments, etc.). FIG. 1 is illustrated by being implemented in white (white), and when configured in black, visibility is further improved by color contrast with the image transmitted through the nanofiber layer 2 .

The polyvinylidene fluoride (PVDF) polymer is a polymer having a repeating unit of (-CF2-CH2-)n, and may have various crystal forms, and basically TGTG' (T=trans, G=gauche+, G'= There are gauche-) crystals of α crystals, β crystals having a (TTTT) configuration, all of which are trans, and γ crystals having a TTTGTTTG′ configuration.

The principle of electrospinning is that when an electric field is applied to a polymer solution, an electric force is applied to the particles and positive charges are oriented on the surface of the solution to induce the particles to the interface between the air layer and the surface of the solution. A force opposite to the tension is generated. At this time, as the solution overcomes the surface tension above the threshold voltage, the solution injected by the potential difference with the metal collector on the opposite side is collected by the collector. According to this principle, it is possible to manufacture nanofibers through a polymer solution.

In the case of producing a PVDF nanofiber web through the electrospinning method, the PVDF fiber by the electric field generated when the polymer solution (+) sprayed in the electrospinning process is solidified and then collected on the electrode (integrator) (-pole) Since the internal dipole arrangement (CF) occurs at the same time, a separate polarization treatment process is not required, and PVDF having a high β-crystal content inside the fiber can be manufactured.

On the other hand, a typical MB filter (or HEPA filter) absorbs and collects dust in an electrostatic method, so it is weak to moisture or moisture, so when worn for a long time, performance deteriorates and shrinks. Because it blocks ultra-fine dust and viruses with a physical method that filters out the entangled fiber strands, it is hardly affected by moisture or moisture. there is an effect

In addition, since polyvinylidene fluoride (PVDF), which is electrospun when forming the nanofiber layer 2, is a ferroelectric material and has its own static charge, fine dust and the like are more effectively collected.

Table 1 below is a test result table for the amount of PBBs (Polybrominated biphenyls) detected for the nanofiber filter of the present invention, and it can be seen that various harmful components are detected below the detection limit, so that it is safe for use in the human body.

Test Items Result (unit: mg/kg) Test Methods detection limit Monobromobiphenyl less than 5



IEC 62321-6:2015 5 Dibromobiphenyl less than 5 5 Tribromobiphenyl less than 5 5 Tetrabromobiphenyl less than 5 5 Pentabromobiphenyl less than 5 5 Hexabromobiphenyl less than 5 5 Heptabromobiphenyl less than 5 5 Octabromobiphenyl less than 5 5 Nonabromobiphenyl less than 5 5 Decabromobiphenyl less than 5 5

Table 2 below is a test result table for PBDEs (Polybrominated diphenyl ethers) detection amount, and it can be seen that various harmful components are detected or not detected below the detection limit (less than 5 mg/kg), so it is safe to use on the human body.

Test Items Result (unit: mg/kg) Test Methods detection limit Monobromobiphenyl less than 5



IEC 62321-6:2015 5 Dibromobiphenyl less than 5 5 Tribromobiphenyl less than 5 5 Tetrabromobiphenyl less than 5 5 Pentabromobiphenyl less than 5 5 Hexabromobiphenyl less than 5 5 Heptabromobiphenyl less than 5 5 Octabromobiphenyl less than 5 5 Nonabromobiphenyl less than 5 5 Decabromobiphenyl less than 5 5

Table 3 below is a pralate detection amount test result table, and it can be seen that various harmful components are detected below the detection limit of 0.01%, indicating that it is safe to use on the human body.

Test Items Result (unit: %) Test Methods detection limit DEHP less than 0.01
IEC 62321-6:2015 0.01 BBP less than 0.01 0.01 DBP less than 0.01 0.01

* DEHP : DI(2-ETHYLHEXYL)-PHTHALATE *BBP: BENZYLBUTYLPHTHALATE

* DBP: DIBUTYLPHTHALATE

Table 4 below is a test result table for the amount of formaldehyde detected.

Test Items Results (unit: mg/kg) Test Methods detection limit formaldehyde not detected KS K ISO 14184-1:1998 20 (mg/kg)

According to Table 4 above, in the nanofiber filter manufactured according to the embodiment of the present invention, heavy metals, volatile organic compounds (VOCs), volatile aromatic hydrocarbons (VACs), total volatile organic compounds (TVOC), toluene, formaldehyde All were found to be non-detection or trace amount detected to a level that satisfies the certification standards, and formaldehyde was not detected in the test standards expected when the nanofiber filter of the present invention was applied to various filters and masks, thus satisfying the certification standards. .Table 5 below is a quantitative test result table for other hazardous substances, and it can be seen that it is safe even if it is used in the human body because it is below the quantitative limit or not detected.

Test Items result
(Unit: mg/kg) Test Methods limit of quantification
(Unit: mg/kg) Methylisothiazolinone
(MIT) non-detection Regulations on standards and methods for testing and inspection of household chemical products subject to safety verification [National Institute of Environmental Sciences Notice No. 2019-70 (2019.12.31.)] One Benzisothiazolinone
(BENZISOTHIAZOLIONE) non-detection One 2-octyl-3(2H)isothiazolone
(OIT) non-detection One 5-chloromethylisothiazolinone
(5-CHLOROMETHYLISOTHIAZOLINONE) non-detection One

Table 6 below is a table of UV blocking rate test results, and it can be seen that the UV blocking rate is excellent.

Test Items Result (unit: nm) measuring instrument Wavelength interval Ultraviolet (UV-R) blocking rate 70.3/44.5/55.6/59.4 UV-VIS-NIR Spectrophotometer
(Perkin Elmer_Lamb 1050 with 150 mm InGaAs int. Sphere) 5nm Ultraviolet (UV-A) blocking rate 63.4/37.6/47.8/51.7 5nm Ultraviolet (UV-B) blocking rate 93.3/66.9/80.9/84.9 5nm

* Wavelength range UV-R : 290~400nm, UV-A : 315~400nm, UV-B : 290~315nm * Individual values are indicated due to the deviation of data for each part.

Table 7 below is a transmittance test result table of the nanofiber filter of the present invention. As a result of testing three times for 30 seconds using a filter tester (filter tester (Lorenz FMP03)) and aerosol type paraffin oil, the transmittance of the nanofiber filter was 2.9% and the filter efficiency was 97.1%, resulting in very good results.

transmittance 2.9% efficiency 97.1%

* Test equipment: filter tester (Lorenz FMP03) * Aerosol form: paraffin oil

* Aerosol average particle size: 0.44㎛

* Aerosol concentration: (20±5) ㎎/㎥

* Flow rate: 95 L/min (min)

* Number of measurements: 3 times

* Measurement time: 30 seconds

* Efficiency: 100 - Transmittance (%)

In addition, the 'differential pressure', which is the pressure difference before and after passing through the nanofiber layer 2, is measured to be 1.4, indicating that breathing is very convenient. For example, among the masks approved by the Ministry of Food and Drug Safety, in the case of KF-94 products, the differential pressure is about 7-8, and in the case of KF-80, the differential pressure is 6-7, making it difficult to breathe, whereas the present invention has a nanofiber filter of about 1.4.

Table 8 below is a test result table for the burst strength of the second mesh layer 3 of the nanofiber filter of the present invention, and very excellent results were obtained.

Test Items result test standard burst strength 419.N KS K 0350:2017, (C.R.E) Ball busting method

Table 9 below is a test result table for the tensile strength of the warp and weft of the second mesh layer 3 of the nanofiber filter of the present invention, and very excellent results were obtained.

Test Items result test standard Warp Tensile Strength 270N KS K 0520: 2015, C.R.E, grab method) Weft Tensile Strength 280N

Table 10 below is a result table of the present invention antimicrobial test (KS K0693: 2016), and the sample used for the antimicrobial test is the nanofiber layer (2) of the nanofiber filter, and test strains 1 and 2 The antibacterial degree was tested by adding 0.05% of a nonionic surfactant to the bacterial solution.

division Bacteria immediately after inoculation Number of bacteria after 18 hours bacteriostatic reduction rate strain 1 Sample (BLANK) 1.8 × 10 ⁴ /ml 8.7 × 10 ⁶ /ml - Nanofiber filter of the present invention - <10/ml 99.9% strain 2 Sample (BLANK) 1.8 × 10 ⁴ /ml 3.0 × 10 ⁷ /ml - Nanofiber filter of the present invention - 1.2 × 10 ⁴ /ml 99.9%

In Table 10, 'Strain 1' is Staphylococcus aureus ATCC 6538, 'Strain 2' is Klebsiella pneumonian ATCC 4352, the standard cloth is 'Nanofiber layer (2)', and the nonionic surfactant is TWEEN 80 inoculated with 0.05 % added, and '<' means a value less than. FIGS. 7 and 8 are antibacterial test photos for strain 1 (Staphylococcus aureus ATCC 6538), and FIG. 7 is a bacterial solution (1.8× of the sample). 10 ⁴ ) is a photograph, and FIG. 8 is a photograph of the test result after 18 hours, showing that the number of bacteria in 'Strain 1' is less than 10 and 99.9% is removed, indicating that the antibacterial degree is very good.

9 and 10 are antibacterial test pictures for strain 2 (Klebsiella pneumonian ATCC 4352), FIG. 9 is a bacterial fluid (1.8×10 ⁴ ) of the sample (Blank), and FIG. As a result, it can be seen that the number of bacteria in 'Strain 2' is 1.2×10 ⁴ and 99.9% is removed, indicating that the antibacterial degree of the nanofiber filter of the present invention is very good.

As can be seen from the above antibacterial test results, in the case of the 'nano fiber layer (2)' sample, the initial number of bacteria in strains 1 and 2 was 1.8 × 10 ^4, but almost all of them were removed after 18 hours, indicating that the antibacterial degree is very good. Therefore, there is an effect of bringing an effect to the health of the user and further to the improvement of public health and hygiene.

The present invention has superior visibility, air permeability, water repellency and antibacterial properties compared to microfiber filters of the same performance, and can be easily washed by rinsing with water, so that it can be used repeatedly.

The present invention is harmless to the human body and environment-friendly, and various kinds of things can be safely used because various bacteria, pathogens, microorganisms, viruses, etc. are killed in a short time by the antibacterial action.

The nanofiber filter according to the present invention is applied to various electronic products such as a face mask, dustproof clothing or protective clothing, dustproof net, air purifier, air conditioner, etc., automobile, ventilation air filter, transportation air filter, industrial filter, clean room equipment, etc. It can be used, and the range of its use is not limited within the area of the air filter.

The present invention described as described above is not limited to the present embodiment and the accompanying drawings, and various substitutions, modifications and changes are possible within the scope without departing from the technical spirit of the present invention, which in the technical field to which the present invention pertains It is obvious to those with ordinary knowledge.

(1)--The first mesh layer (2)--Nanofiber layer (3)--Second mesh layer

Claims (14)

a) putting the first mesh layer into an electrospinning device;
b) forming a nanofiber layer by electrospinning a polyvinylidene fluoride (PVDF) solution on the first mesh layer;
c) rough coating of an eco-friendly water-based adhesive on the upper surface of the nanofiber layer and the lower surface of the second mesh layer with a roller;
d) winding the nanofiber layer and the second mesh layer on a paper tube or drum, respectively, and then leaving it at room temperature for 2 to 6 hours to permeate the water-based adhesive with the rough coating to permeate into the nanofiber layer and the second mesh layer;
e) finishing coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer with a roller;
f) thermocompression bonding and bonding by passing the first mesh layer and the nanofiber layer coated with an environmentally friendly water-based adhesive between the upper and lower rollers heated to a temperature of 60 to 90° C.;
g) complete drying at room temperature for 48 to 96 hours;
A nanofiber filter manufacturing method comprising a. a`) rough coating of an eco-friendly water-based adhesive on the upper surface of the first mesh layer with a roller;
b`) natural drying at room temperature so that the moisture content of the first mesh layer coated with the rough coating is maintained at 40-60%;
c`) putting the first mesh layer into the electrospinning device;
d`) forming a nanofiber layer by electrospinning a polyvinylidene fluoride (PVDF) solution on the first mesh layer;
e`) coating the top surface of the nanofiber layer and the bottom surface of the second mesh layer with an eco-friendly water-based adhesive with a roller;
f`) winding the nanofiber layer and the second mesh layer on a paper tube or drum, respectively, and then leaving it at room temperature for 2 to 6 hours to permeate the water-based adhesive coated with the chaebol to permeate into the nanofiber layer and the second mesh layer;
g`) finishing coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer with a roller;
h`) passing the nanofiber layer and the second mesh layer between the upper and lower rollers heated to a temperature of 60 to 90° C., followed by thermocompression bonding and bonding;
i`) drying completely at room temperature for 48 to 96 hours to obtain a nanofiber filter;
A nanofiber filter manufacturing method comprising a. The method according to claim 1 or 2;
Instead of step g) or i`) to obtain a nanofiber filter by drying completely at room temperature for 48 to 96 hours, heat and dry the nanofiber filter for 12 to 24 hours in a drying room at 60 to 90 ° C. to obtain;
A nanofiber filter manufacturing method comprising a. The method according to claim 1 or 2;
The coating amount of the water-based adhesive is a nanofiber filter manufacturing method, characterized in that 8 ~ 30g / ㎡. The method according to claim 1 or 2;
water-based adhesive,
5 to 15% by weight of water, 10 to 22% by weight of an aqueous EVA copolymer, 65 to 75% by weight of an aqueous acrylic copolymer, and 2 to 5% by weight of a VOC reducing agent. 6. The method of claim 5;
The VOC reducing agent,
69 to 90% by weight of water, 4 to 12% by weight of thiourea, 1 to 4% by weight of urea, and 1 to 4% by weight of boric acid. 6. The method of claim 5;
A nanofiber filter manufacturing method further comprising 1 to 10% by weight of adipic dihydrazide (ADIPIC DIHYDRAZIDE). 6. The method of claim 5;
Further comprising 2 to 8% by weight of a water-repellent solution,
The water-repellent liquid is a nanofiber filter manufacturing method, characterized in that the water-repellent liquid is either an eco-friendly fluorine-based water-repellent liquid or a silicone-based water-repellent liquid. 6. The method of claim 5;
The glass transition temperature of the water-based adhesive is -25 to 0 ° C, and the viscosity is 300 to 800 cps. A nanofiber filter manufactured by the manufacturing method of any one of claims 1 to 9. A nanofiber filter comprising a nanofiber filter manufactured by the manufacturing method of any one of claims 1 to 9, wherein the nanofiber layer is transparent white, and the transparency is 70 to 90%. The nanofiber filter manufactured by the manufacturing method of any one of claims 1 to 9 is characterized in that it is any one of a mask, a hat, gloves, a dustproof suit, a protective suit, a dustproof net, an air purifier, an air filter for ventilation, an air filter for transportation, and an industrial filter. nanofiber filter. a first mesh layer consisting of a fiber mesh of a predetermined mesh;
a nanofiber layer electrospun and bonded to the upper surface of the first mesh layer with a polyvinylidene fluoride (PVDF) solution;
a second mesh layer adhered to the upper surface of the nanofiber layer and composed of a fiber mesh of a predetermined mesh; including,
The air permeability of the nanofiber layer is 80 to 150 cfm,
The basis weight of the nanofiber layer is 0.05 ~ 0.5gsm,
The first mesh layer is 6,400 to 10,000 mesh, and the basis weight is 15 to 30 gsm,
The second mesh layer is 1,225 ~ 3,025 mesh and the basis weight is 40 ~ 55gsm nanofiber filter. 14. The method of claim 13;
The color of the nanofiber layer is transparent white, and the transparency is 70-90% of the nanofiber filter.

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