KR102161587B1 - Nano fiber filter and its manufacturing method - Google Patents

Abstract

The present invention relates to a nano-fiber filter and a manufacturing method thereof, capable of securing antibacterial properties, breathability and visibility, and obtaining excellent collection efficiency such as dust including infectious pathogens, and capable of being applied to various objects including the human body by being adhered with an eco-friendly aqueous adhesive. The manufacturing method thereof comprises the steps of: a) introducing a first network layer into an electrospinning device; b) forming a nano-fiber layer by electrospinning a polyvinylidene fluoride (PVDF) solution on the first network layer; c) initial coating an eco-friendly aqueous adhesive with a roller on an upper surface of the nano-fiber layer and a lower surface of a second network layer; d) winding the nano-fiber layer and the second network layer on a paper pipe or drum, respectively, and leaving the same at room temperature for 2 to 6 hours to penetrate the initial coated aqueous adhesive into the nano-fiber layer and the second network layer; e) finish-coating the eco-friendly aqueous adhesive on the upper surface of the nano-fiber layer with the roller; f) thermally compressing and bonding the first network layer, the nano-fiber layer finish-coated with the eco-friendly aqueous adhesive, and the second network layer by passing the same between upper and lower rollers heated at temperature of 60 to 90°C; and g) completely drying for 48 to 96 hours at room temperature. In addition, the nano-fiber filter manufactured by the manufacturing method is included.

Description

Nano fiber filter and its manufacturing method {Nano fiber filter and its manufacturing method}

The present invention relates to a nanofiber filter and a method of manufacturing the same, and in detail, by adhering the nanofiber layer and the nanofiber layer protective net layer with an eco-friendly water-based adhesive, it has excellent antibacterial properties, breathability and visibility, and is applied to various objects including the human body. It is possible to do, and to obtain excellent collection efficiency of various dusts including infectious pathogens.

In general, nanofibers refer to microfibers whose diameter is only tens to hundreds of nanometers, and are produced by an electric field. In other words, nanofibers apply a high voltage electric field to the raw material polymer material to generate an electric repulsion inside the raw material polymer material, and as a result, the molecules are aggregated and split into nano-sized yarns. Is manufactured and produced. At this time, the stronger the electric field, the thinner the polymer material as the raw material is torn, so that nanofibers having a fineness of 10 nm to 1,000 nm can be obtained.

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

Conventional air filters made of simple non-woven fabrics are widely used in various applications due to their simple manufacturing process and low cost, but have a disadvantage of low dust filtration efficiency. There is a problem with poor collection ability.

Among the shortcomings of the nonwoven air filter, an air filter using a nonwoven fabric to which an electrostatic charge is added has been developed and used to compensate for the fine dust collection efficiency. However, the electrostatic characteristics of the electrostatic filter are affected by contact with rain or moisture. As a result, there is a problem in that the dust collection efficiency is rapidly lowered. For example, the reduction in dust collection efficiency due to the decrease in electrostatic characteristics has several problems, such as decreasing from the initial dust collection efficiency of 99,97% to about 30%.

Republic of Korea Patent Publication No. 10-1585506 (Name of the invention: PVDF nanofiber-based patterned flexible piezoelectric element using electrospinning and its manufacturing method, 2016. 01. 15. Patent notice) Korean Registered Patent Publication No. 10-1079775 (Name of the invention: Method for manufacturing electrically conductive nanofibers through electroless plating followed by electrospinning, 2011. 11. 03. Patent notice)

The present invention adheres the nanofiber layer and the protective net layer of the nanofiber layer with an eco-friendly water-based adhesive to provide excellent antibacterial properties, breathability, and visibility, and can be applied to various objects including the human body, and excellent collection of dust, including infectious pathogens. An object is to provide a nanofiber filter capable of obtaining efficiency and a method of manufacturing the same.

The method for manufacturing a nanofiber filter according to an embodiment of the present invention includes: a) introducing a first mesh layer into an electrospinning device, and b) electrospinning a polyvinylidene fluoride (PVDF) solution on the first mesh layer to form a nanofiber layer. And; c) precoating 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 net layer on a paper pipe or drum, respectively, and leaving it at room temperature for 2 to 6 hours to allow the uncoated aqueous adhesive to penetrate into the nanofiber layer and the second net 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 eco-friendly water-based adhesive and the second mesh layer between the upper and lower rollers heated at a temperature of 60 to 90°C; g) Complete drying at room temperature for 48 to 96 hours.

The nanofiber filter manufacturing method of another embodiment of the present invention includes the steps of: a`) precoating an eco-friendly aqueous adhesive on the upper surface of the first mesh layer with a roller; b`) naturally drying at room temperature so that the moisture content of the first network layer coated with the rough coating is maintained at 40-60%; c`) introducing the first network layer into the electrospinning device; d`) forming a nanofiber layer by electrospinning a polyvinylidene fluoride (PVDF) solution on the first network layer; e`) coating 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; f`) winding the nanofiber layer and the second net layer on a paper pipe or drum, respectively, and leaving it at room temperature for 2 to 6 hours to penetrate the chaebol-coated aqueous adhesive so as to permeate the nanofiber layer and the second net 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 at a temperature of 60 to 90°C, thereby thermally compressing and bonding; i`) It includes the step of obtaining a nanofiber filter by completely drying at room temperature for 48 to 96 hours.

Instead of obtaining a nanofiber filter by completely drying at room temperature for 48 to 96 hours, it includes the step of obtaining a nanofiber filter by 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. .

The eco-friendly aqueous 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 amount of the aqueous adhesive coating (application) may be 8 to 30 g/m 2.

The glass transition temperature (Tg value) of the aqueous adhesive may be -25 to 0°C.

Adipic dihydrazide (ADIPIC DIHYDRAZIDE) of 1 to 10% by weight mixed in the aqueous adhesive may be further included.

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

The glass transition temperature of the aqueous 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 one of the above manufacturing methods.

The nanofiber filter includes a first mesh layer composed of a fiber mesh of a predetermined mesh, a nanofiber layer electrospun and bonded with a polyvinylidene fluoride (PVDF) solution on an upper surface of the first mesh 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 network layer may be 6,400 to 10,000 mesh and a basis weight of 15 to 30 gsm.

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

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

The amount of the water-based adhesive coated on the first and second net layers and nanofiber layers may be 8 to 30 g/m 2.

The present invention has high transparency, excellent visibility, and fine dust viruses 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.

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

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

The present invention has excellent visibility and transmittance, so that about 70 to 80% of the transmission is transmitted, so that the object to be applied can be easily identified. For example, in the case of a face mask worn on the face, it is possible to check the entire face including the face of the wearer, and facial makeup expressed on the face (face) of the wearer or the aesthetics or aesthetic emotion expressed on the face are naturally expressed to the outside. It has the effect of becoming, and it has the effect of showing off the beauty to the people around you.

In addition, since the general MB filter (or HEPA filter) absorbs and collects fine dust through an electrostatic method, it is weak to moisture or moisture, so if worn for a long time, performance deteriorates and shrinks. However, the nanofiber filter of the present invention is Because nano-scale fiber strands are entangled and filtered to block dust, dust and viruses, it is hardly affected by moisture or moisture, and various harmful components are not detected in the safety test or are used with confidence. It can have an effect.

In the present invention, even if various dusts, fine dusts, various foreign substances, bacteria, bacteria, viruses, etc. adsorbed or adhered to the nanofiber layer 2 are attached, they can be easily separated (desorbed) by rinsing in water, preferably flowing water. There is an effect that can be used repeatedly.

In the present invention, since the multilayered nanofiber filter is well bonded by an aqueous adhesive that is harmless to the human body, there is an effect that it can be usefully used as a human body coating such as a mask, hat, and gloves.

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

The present invention is not harmless to the human body because no harmful heavy metals, other harmful substances, and formaldehyde are detected, and bacteria, molds, bacteria, viruses, etc. are blocked and killed in a short time.

The present invention is a very useful invention that not only visually recognizes the face when applied as a face mask due to high transparency, but also prevents (prevents) the transmission of viruses, bacteria, bacteria, and pathogens caused by saliva or droplets. to be.

Figure 1: An exemplary configuration of the present invention nanofiber filter.
Figure 2: A flow chart of a nanofiber filter manufacturing method shown in an embodiment of the present invention.
Figure 3: A flow chart of a nanofiber filter manufacturing method shown in another embodiment of the present invention.
Figure 4: Scanning electron microscope image (228 magnification) of a state in which a nanofiber layer is formed on the first network layer in the present invention.
Figure 5: Scanning electron microscope image (5,000 magnification) showing the nanofiber layer in the present invention.
Figure 6: 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 experiment.
Figure 8: A photograph of the test result of strain 1 in the present invention antibacterial activity experiment (18 hours elapsed).
Figure 9: Blank photograph of strain 2 in the present invention antibacterial activity experiment.
Figure 10: A photograph of the test result of strain 2 in the present invention antibacterial activity experiment (18 hours elapsed).
Figure 11: A photograph showing the transmittance of the inventive 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 indicated with 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 the accompanying drawings The items expressed in are schematic drawings for easy explanation of embodiments of the present invention and may be different from the actual implementation form.

1 is an illustration of the layer structure of the nanofiber filter of the present invention, a first mesh layer 1 composed of a fibrous mesh of a predetermined mesh, and polyvinylidene fluoride on the upper surface of the first mesh layer 2 (PVDF: Polyvinylidene fluoride) solution electrospinning and bonding a nanofiber layer 2, and a second network layer 3 adhered to the upper surface of the nanofiber layer 2 and composed of a fibrous mesh of a predetermined mesh.

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

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

The first and second net layers 1 and 3 are adhered or immobilized on the upper and lower surfaces of the nano fiber layer 2 to sufficiently protect the nano fiber layer 2 and maintain breathability, visibility, and durability.

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

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

The weft and warp constituting the first and second net layers (1) (3) are olefin-based polypropylene (PP), polyvinyl acrylate (PVA), polyacnionitrile (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), dimethylfluoro (DMF), dimethyl sulfoxide (DMSO), chlorobenzene (CB), trichloroethanol (TCE), trifluoroethylene (TFE), tetrahydrofuran (THF), At least one solvent selected from the group consisting of methyl ethyl ketone (MEK), toluene, xylene, formic acid, acetic acid, and water; It is produced by extrusion at a mixing ratio of 8 to 20% by weight: 92 to 80% by weight.

The amount of water-based adhesive coated on the first and second network layers 1 and 3 and the nanofiber layer 2 (coating amount) is 8 to 30 g/m 2. If the amount of the water-based adhesive is less than 8g/m2, the desired adhesive strength cannot be obtained. If the amount of the water-based adhesive exceeds 30g/m2, it is not only wasted, but also the nanofiber layer 2 and the nanocell are broken due to excessive amounts. ), can be damaged and/or destroyed, which is not desirable.

The first mesh layer 1, the nanofiber layer 2, and the second mesh layer 3 are adhered with an eco-friendly aqueous adhesive that is harmless to the human body. The aqueous adhesive is harmless and safe to the human body by using an eco-friendly material that does not smell and does not contain harmful substances.

FIG. 2 shows a method of manufacturing a nanofiber filter according to an embodiment of the present invention. After the first mesh layer 1 is introduced into the electrospinning device (step S1), polyvinylidene fluoride is formed on the first mesh layer 1 (PVDF) The solution is electrospinned to form the nanofiber layer 2 (step S2), and an eco-friendly aqueous adhesive is coated on 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), and the nanofiber layer (2) and the second mesh layer (3) coated with the eco-friendly water-based adhesive are wound on a paper pipe or drum, respectively, and then left at room temperature for 2 to 6 hours to make a first roll. The coated water-based adhesive penetrates into the nanofiber layer (2) and the second mesh layer (3) sufficiently (step S4), and an eco-friendly water-based adhesive is coated on the upper surface of the nanofiber layer (2) with a roller (finish roll coating). ) And (S5 step), the first mesh layer (1) and the nanofiber layer (2) and the second mesh layer (3) coated with an eco-friendly water-based adhesive are passed through the upper and lower rollers heated at a temperature of 60 to 90°C. It is subjected to thermocompression bonding and bonding (step S6), and completely dried 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 may be obtained by 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 (step S8).

3 shows a method of manufacturing a nanofiber filter according to another embodiment of the present invention, in which an eco-friendly aqueous adhesive is first roll coated with a roller on the upper surface of the first net layer 1 (step S11), Dry naturally at room temperature so that the water content of the first mesh layer 1 coated with the adhesive 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 a 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 with an eco-friendly water-based adhesive on a roller (step S15), and then the nanofiber layer (2) and the second net layer (3) coated with the eco-friendly water-based adhesive are wound on a paper tube or drum, respectively, and then 2~6 Leave at room temperature for a period of time to penetrate so that the chaebol-coated aqueous adhesive sufficiently penetrates into the nanofiber layer (2) and the second mesh layer (3) (step S16), and finishes the eco-friendly water-based adhesive on the upper surface of the nanofiber layer (2) with a roller. After coating (finish roll coating) (S17 step), 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 at a temperature of 60 to 90°C. It is passed through the upper and lower rollers, thermally compressed and bonded (step S18), and 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 may be obtained by 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 (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, and becomes transparent after drying (or curing) and no traces are left.

The eco-friendly aqueous 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 aqueous adhesive is -25 ~ 0 ℃, the viscosity is 300 ~ 800 cps.

If the glass transition temperature is less than -25°C, the bendability (ductility) of the nanofiber filter becomes too soft and the shape can be easily deformed.If the glass transition temperature exceeds 0°C, the nanofiber filter becomes hard and worn. It is desirable to have a glass transition temperature of -25°C to 0°C, which is soft and has excellent adhesion, since 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 referred to as an ethylene vinyl acetate copolymer. As the content of vinyl acetate increases, the density increases, but the degree of crystallization decreases, thereby increasing the flexibility. 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 for foam molding products such as sandals and soles, agricultural films, and stretch films for business, such as soft vinyl chloride. High-concentration EVA is used as a raw material for adhesives.

The acrylic resin refers to a polymer from an ester such as acrylic acid or methacrylic acid. A typical polymer of methyl methacrylate (methyl methacrylate) is colorless, transparent, and transmits light, especially ultraviolet rays, better than ordinary glass (refractive index of 1.49). It does not discolor even when exposed to the 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, and in the VOC reducing agent As a result, components such as volatile organic compounds (VOC) and formaldehyde are adsorbed and deodorized, so they are 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 the oxygen atom of urea is substituted with a sulfur atom. Also known as ocabamide. Thiourea has a molecular weight of 7312, a melting point of 180°C, and a specific gravity of 1405. Soluble in water and ethanol, but hardly soluble in ether. The aqueous solution is neutral and has a bitter taste. When hydrolyzed with acid or alkali, it decomposes into ammonia, hydrogen sulfide, and carbon dioxide. When oxidized with potassium permanganate, it becomes urea and has excellent deodorizing effect.

The urea is an organic compound having a chemical formula of CO(NH ₂ ) ₂ , which is a colorless crystalline substance, and is a final decomposition product of protein metabolism in all mammals and some fish. Also called diaminomethanal, it has no color or odor and makes columnar crystals. Its molecular weight is 60047, its melting point is 1327℃ (1atm), and its specific gravity is 1335. Since it is a highly polar material, it is well soluble in water and alcohol, but not in ether.

The boric acid (H ₃ BO ₃ ) is an oxygen acid generated by hydration of boron oxide, and includes orthoboric acid, metaboric acid, tetraboric acid, etc., and usually refers to orthoboric acid. Orthoboric acid is a raw material for borosilicate glass and glaze of ceramics, and it also promotes dissolution of injections. Orthoboric acid is colorless, transparent or scale-like crystals with a white luster. It has no odor and has a characteristic 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, odor, and can be safely used in any climatic condition, prevents the propagation of various molds and bacteria, and prevents bacteria, pathogens, bacteria, Viruses and the like are killed in a short time.

The present invention may further include 1 to 10% by weight of adipic dihydrazide (ADH: ADIPIC DIHYDRAZIDE) mixed in 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, thus forming a total of 26 atoms. 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. The appearance is white powder or aqueous adhesive. As it is mixed and liquefied, it greatly contributes to reducing the formaldehyde of the nanofiber filter coated with the aqueous adhesive.

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

Although the polyvinylidene fluoride (PVDF) of the present invention has its own water repellent function, the water repellency 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.

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

In FIG. 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 are formed in the form of a web, and pores formed between the nanofiber yarns (nanocell ) Is in the range of at least 50 ㎚ to 1 µm, and ventilation and breathing are achieved while entering and leaving air 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 diameter of the nanofiber yarn of the nanofiber layer 2 may be 100nm to 300nm. When the diameter of the nanofiber yarn is larger than 300 nm, micro-fineization is not sufficient, the fiber surface area is lowered, and the collection efficiency as a filter medium for a filter decreases, making it difficult to remove fine dust, etc., on the contrary, when it is smaller than 100 nm, processability It decreases, the density increases, the differential pressure increases, the strength decreases, and production is difficult.

In the present invention, even if various dusts, fine dusts, various foreign substances, bacteria, bacteria, viruses, etc. adsorbed or adhered to the nanofiber layer 2 are attached, they can be easily separated (desorbed) by rinsing in water, preferably flowing water. So it can be used repeatedly.

The color of the polyvinylidene fluoride (PVDF) is transparent white (white) or white (white) with high transparency, and thus transparency, that is, visibility is high, so that objects located in the rear can be identified.

The first mesh layer (1) and the second mesh layer (3) of the nanofiber filter of the present invention are translucent or opaque, but the color of the polyvinylidene fluoride (PVDF) constituting the nanofiber layer (2) is transparent or white with high transparency. It is (white) and has high visibility, so you can see objects located in the rear.

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 in the rear are transmitted, so it is differentiated from existing opaque face masks. , If a face mask is worn on the face, it can be seen through the wearer's face as well, and the entire face including the wearer's face can be seen, so that facial makeup and aesthetics or aesthetic emotions expressed on the face are untouched. It works.

In addition, when applied to a face mask, the face is naturally exposed, not mainly used for crime or masking purposes, while airborne dust, fine dust, yellow dust, pollen, dust, etc., biological particles such as bacteria and mold, and bacteria , It can be usefully used as various filters, masks, coatings, etc. to remove biologically infectious (MERS/SARS/Coronavirus infection-19 (Corona-19), etc.) or harmful substances such as viruses and droplets.

The transparency of the nanofiber filter may be changed according to the size and number of nanopores formed 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 exemplified by implementing in white (white), and when configured in black, visibility is further improved by color contrast with an 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 crystalline forms, basically TGTG'(T=trans, G=gauche+, G'= There are gauche-)-shaped α crystals, β crystals having an arrangement of (TTTT), which are all trans types, and γ crystals having an arrangement of TTTGTTTG'.

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 a positive charge is oriented on the surface of the solution, and the particles are guided 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 sprayed solution is collected by the collector due to a potential difference with the metal collector on the opposite side. According to this principle, it is possible to manufacture nanofibers through a polymer solution.

In the case of manufacturing the PVDF nanofiber web through the electrospinning method, PVDF fibers are generated by the electric field generated when the polymer solution (+) sprayed in the electrospinning process is solidified and then collected in the electrode (integrator) (-pole). Since the internal dipole array (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 general MB filter (or HEPA filter) absorbs and collects dust through an electrostatic method, so it is weak to moisture or moisture, so if worn for a long time, performance deteriorates and shrinks. However, the nanofiber filter of the present invention has a fine nano unit It is hardly affected by moisture or moisture because it blocks ultrafine dust or viruses by a physical method of entangled and filtering the fibers of the fiber, and it is safe to use because various harmful components are not detected or are below the standard value in the safety test. There is an effect.

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

Table 1 below is a test result table for the amount of detection of polybrominated biphenyls (PBBs) 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 even when used in the human body.

Test Items Results (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 the detection amount of PBDEs (polybrominated diphenyl ethers), and it can be seen that various harmful components are detected or not detected as less than the detection limit (less than 5 mg/kg), so that they are safe even when used in the human body.

Test Items Results (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 test result table for the detection amount of pralate, and it can be seen that various harmful components are detected as less than 0.01% of the detection limit, so that they are safe even when used in humans.

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, and it can be seen that it is safe even if it is used in the human body because it is not 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, in the items of heavy metals, volatile organic compounds (VOCs), volatile aromatic hydrocarbons (VACs), total volatile organic compounds (TVOC), toluene, and formaldehyde. All were found to be non-detected or trace amounts to the level that satisfies the certification criteria, and formaldehyde was not detected in the expected test criteria when applying the nanofiber filter of the present invention to various filters and masks, so the certification criteria were satisfied. .

Table 5 below is a table of quantitative test results for other hazardous substances, and it can be seen that it is safe even if it is used for humans because it is below the limit of quantification or is not detected.

Test Items result
(Unit: mg/kg) Test Methods Limit of quantification
(Unit: mg/kg) Methylisothiazolinone
(MIT) Not detected Regulations on standards and methods, etc. for testing and inspection of household chemical products subject to safety confirmation [National Institute of Environmental Sciences Notice No. 2019-70 (December 31, 2019)] One Benzisothiazolinone
(BENZISOTHIAZOLIONE) Not detected One 2-octyl-3(2H)isothiazolone
(OIT) Not detected One 5-chloromethylisothiazolinone
(5-CHLOROMETHYLISOTHIAZOLINONE) Not detected One

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

Test Items Results (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 the data for each part.

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

Transmittance 2.9% efficiency 97.1%

* Test equipment: filter tester (Lorenz FMP03)

* Aerosol form: Paraffin oil

* Average aerosol particle size: 0.44㎛

* Aerosol concentration: (20±5) ㎎/㎥

* Flow: 95 L/min (min)

* Number of measurements: 3 times

* Measurement time: 30 seconds

* Efficiency: 100-Transmittance (%)

In addition, the'differential pressure', which is the difference in pressure between before and after passing through the nanofiber layer 2, was measured as 1.4, indicating that it is very easy to breathe. For example, among the masks approved by the Ministry of Food and Drug Safety, the KF-94 product has a differential pressure of about 7 to 8, and the KF-80 has a differential pressure of 6 to 7, while it is difficult to breathe, the nanofiber filter in the present invention is easy to breathe at about 1.4.

Table 8 below is a test result table for the bursting 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 Bursting strength 419.N KS K 0350:2017, (C.R.E) Ballbusting 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 Tensile strength of inclination 270N KS K 0520: 2015, C.R.E, Grab method) Tensile strength of weft 280N

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

division Number of bacteria right after vaccination Count 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'nano fiber layer (2)', and the nonionic surfactant is TWEEN 80 in the inoculum solution. % Is added, and'<' means a value less than.

7 and 8 are photographs of an antibacterial test for strain 1 (Staphylococcus aureus ATCC 6538), FIG. 7 is a photograph of a bacterial solution (1.8×10 ⁴ ) of a sample (Blank), and FIG. 8 is a photograph of the test result after 18 hours. As a result, it can be seen that the number of bacteria in'Strain 1'is less than 10 and 99.9% is removed, so that the antibacterial property is very good.

9 and 10 are photographs of an antibacterial test for strain 2 (Klebsiella pneumonian ATCC 4352), FIG. 9 is a photograph of a bacterial solution (1.8×10 ⁴ ) of a sample (Blank), and FIG. 10 is a photograph of the test result after 18 hours. As the number of bacteria of'Strain 2'was removed by 99.9% to 1.2×10 ⁴ , it can be seen that the antibacterial property of the nanofiber filter of the present invention is very excellent.

As can be seen from the above antimicrobial 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 after 18 hours, almost all of them were removed, indicating very excellent antibacterial properties. It can be seen, and thus, it has an effect of bringing about an effect on the health of the user and the health and hygiene of the public.

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 in water, so that repeated use is possible.

The present invention is harmless to the human body and is environmentally friendly, and various bacteria, pathogens, microorganisms, viruses, etc. are killed in a short time by antibacterial action, so that various objects can be safely used.

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The nanofiber filter according to the present invention can be applied to all kinds of electronic products such as face masks, coverings, dustproof nets, air purifiers, air conditioners, automobiles, air filters for ventilation, air filters for transportation, industrial filters, and clean room facilities. The range of use is not limited within the area of the air filter.

The present invention described above is not limited to the present embodiment and the accompanying drawings, and various substitutions, modifications and changes can be made within the scope of the technical spirit of the present invention, which is in the technical field to which the present invention belongs. This is obvious to those of ordinary knowledge.

(1)--the first mesh layer (2)--the nanofiber layer (3)--the second mesh layer

Claims (16)

a) introducing the first network layer into the electrospinning device;
b) forming a nanofiber layer by electrospinning a polyvinylidene fluoride (PVDF) solution on the first network layer;
c) precoating 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 net layer on a paper pipe or drum, respectively, and leaving it at room temperature for 2 to 6 hours to allow the uncoated aqueous adhesive to penetrate into the nanofiber layer and the second net 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 eco-friendly aqueous adhesive and the second mesh layer between the upper and lower rollers heated at a temperature of 60 to 90°C;
g) completely drying 48 to 96 hours at room temperature; Including,
The aqueous adhesive,
A method of manufacturing a nanofiber filter comprising 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. a`) initial coating of an eco-friendly water-based adhesive on the upper surface of the first mesh layer with a roller;
b`) naturally drying at room temperature so that the moisture content of the first network layer coated with the rough coating is maintained at 40-60%;
c`) introducing the first network layer into the electrospinning device;
d`) forming a nanofiber layer by electrospinning a polyvinylidene fluoride (PVDF) solution on the first network layer;
e`) coating the 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;
f`) winding the nanofiber layer and the second mesh layer on a paper pipe or a drum, respectively, and leaving it at room temperature for 2 to 6 hours to penetrate the chaebol-coated aqueous adhesive so as to penetrate into the nanofiber layer and the second mesh layer;
g`) finishing coating an eco-friendly aqueous adhesive on the upper surface of the nanofiber layer with a roller;
h`) thermocompression bonding and bonding by passing the nanofiber layer and the second mesh layer between the upper and lower rollers heated at a temperature of 60 to 90°C;
i`) obtaining a nanofiber filter by completely drying at room temperature for 48 to 96 hours; Including,
The aqueous adhesive is a nanofiber filter manufacturing method comprising 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 method according to claim 1 or 2;
Instead of step g) or i`) step of completely drying at room temperature for 48 to 96 hours to obtain a nanofiber filter, heat-dry for 12 to 24 hours in a drying room at 60 to 90°C and then dry completely at room temperature for 12 to 24 hours to obtain a nano fiber filter. Obtaining;
Nanofiber filter manufacturing method comprising a. The method according to claim 1 or 2;
Nanofiber filter manufacturing method, characterized in that the coating amount of the water-based adhesive is 8 ~ 30g / ㎡. delete The method according to claim 1 or 2;
The VOC reducing agent,
A method for producing a nanofiber filter, characterized in that it is 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. The method according to claim 1 or 2;
A method for manufacturing a nanofiber filter further comprising 1 to 10% by weight of adipic dihydrazide in the aqueous adhesive. The method according to claim 1 or 2;
Further comprising a water-repellent liquid of 2 to 8% by weight in the aqueous adhesive,
The water-repellent liquid is an eco-friendly fluorine-based water-repellent liquid or a silicon-based water repellent liquid, characterized in that any one of nanofiber filter manufacturing method. The method according to claim 1 or 2;
The glass transition temperature of the aqueous adhesive is -25 ~ 0 ℃, the viscosity is 300 ~ 800cps nanofiber filter manufacturing method. A nanofiber filter manufactured by the nanofiber filter manufacturing method of claim 1 or 2. delete delete delete delete delete delete

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