KR102485703B1 - Nanofiber filter using non-woven fabric and its manufacturing method - Google Patents

Abstract

The present invention is antibacterial, air permeable and visibility secured, excellent collection efficiency such as dust including contagious pathogens can be obtained, and a nanofiber filter that can be applied to various objects including the human body by being adhered with an eco-friendly water-based adhesive and manufacturing the same It relates to a method, comprising: a) introducing a first nonwoven fabric layer into an electrospinning apparatus; b) forming a nanofiber layer by electrospinning a polyvinylidene fluoride (PVDF) solution on the first nonwoven fabric layer; c) first coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer and the lower surface of the second nonwoven fabric layer with a roller; d) winding the nanofiber layer and the second nonwoven layer on a paper tube or drum, respectively, and leaving them at room temperature for 2 to 6 hours so that the first coated aqueous adhesive penetrates into the nanofiber layer and the second nonwoven layer; e) finishing coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer with a roller; f) thermally compressing and bonding the first nonwoven fabric layer, the nanofiber layer coated with the eco-friendly water-based adhesive, and the second nonwoven fabric layer between upper and lower rollers heated to a temperature of 60 to 90 ° C; g) completely drying at room temperature for 24 to 96 hours.
It includes a nanofiber filter manufactured by the above manufacturing method.

Description

Nanofiber filter using non-woven fabric and its manufacturing method

The present invention relates to a nanofiber filter using a non-woven fabric and a method for manufacturing the same, and in detail, a nanofiber layer and a nonwoven fabric protecting the nanofiber layer are bonded with an eco-friendly water-based adhesive to have excellent antibacterial properties and air permeability and protect the human body. It can be applied to various objects including infectious pathogens, and it is possible to obtain excellent filter efficiency for various dusts including infectious pathogens.

In general, nanofibers refer to microfibers having a diameter of only tens to hundreds of nanometers, and are produced by an electric field. In other words, nanofibers apply a high-voltage electric field to polymer materials, which are raw materials, to generate electrical repulsive forces inside the polymer materials, which are raw materials. is manufactured and produced. At this time, the stronger the electric field, the thinner the polymer material, so that nanofibers having a thickness of 1 nm to 1,000 nm can be obtained.

On the other hand, a filter is a filtering 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 filter for particles such as dust or dust in the air, gas, germs, pathogens, mold, bacteria, viruses, etc. It is used for the purpose of removing harmful things like.

Conventional air filters made of simple non-woven fabric are widely used in various fields due to their simple manufacturing process and low cost, but have the disadvantage of poor dust filtration efficiency, and particularly poor ability to collect fine dust of less than 25㎛ that is harmful to the human body. There is a problem.

In order to compensate for the fine dust collection efficiency, which is one of the disadvantages of the non-woven fabric type air filter, an air filter using an electrostatic filter with electrostatic charge has been developed and used, but rain, snow, and condensation (結露), there is a problem in that the dust collection efficiency rapidly decreases as the electrostatic characteristics of the electrostatic filter decrease due to contact or penetration of moisture. That is, there was a problem that the function as a filter was almost lost while the initial dust collection efficiency of 99.97% rapidly decreased to about 30% due to the decrease in electrostatic characteristics as described above.

Republic of Korea Patent Registration No. 10-1585506 (title of invention: PVDF nanofiber-based patterned flexible piezoelectric element using electrospinning method and its manufacturing method, 2016. 01. 15. Patent announcement) Republic of Korea Patent Registration No. 10-1079775 (Title of Invention: Method for Manufacturing Electrically Conductive Nanofibers through Electroless Plating Following Electrospinning, 2011. 11. 03. Patent Publication)

In the present invention, the nanofiber layer and the nonwoven fabric protecting the nanofiber layer are bonded with an eco-friendly water-based adhesive, so that antimicrobial properties, air permeability and visibility are excellent, and it can be applied to various objects including the human body, and is excellent for various dusts including infectious pathogens. An object of the present invention is to provide a nanofiber filter using a non-woven fabric capable of obtaining filter (or collection or dust collection) efficiency and a method for manufacturing the same.

A nanofiber filter manufacturing method using a nonwoven fabric of an embodiment of the present invention includes the steps of a) introducing a first nonwoven fabric layer into an electrospinning apparatus, and b) a polyvinylidene fluoride (PVDF) solution on the first nonwoven fabric layer Or forming a nanofiber layer by electrospinning any one of a polyurethane (PU) solution, and c) first coating an eco-friendly water-based adhesive with a roller on the upper surface of the nanofiber layer and the lower surface of the second nonwoven fabric layer. d) winding the nanofiber layer and the second nonwoven layer on a paper tube or drum, and then leaving them at room temperature for 2 to 6 hours to penetrate the nanofiber layer and the second nonwoven layer so that the first coated aqueous adhesive permeates into the nanofiber layer and the second nonwoven fabric layer; , e) finish coating the upper surface of the nanofiber layer with an eco-friendly water-based adhesive with a roller, and f) the first nonwoven fabric layer, the nanofiber layer coated with the eco-friendly water-based adhesive, and the second nonwoven fabric layer at a temperature of 60 to 90 ° C. Passing between heated upper and lower rollers to perform thermal compression and bonding, and g) completely drying at room temperature for 24 to 96 hours.

A nanofiber filter manufacturing method using a nonwoven fabric of another embodiment of the present invention includes the steps of a`) first coating an eco-friendly water-based adhesive on the top surface of the first nonwoven fabric layer with a roller, and b`) moisture content of the first nonwoven fabric layer naturally drying at room temperature to maintain 40 to 60%; c`) introducing the first nonwoven fabric layer into an electrospinning apparatus; d`) a polyvinylidene fluoride (PVDF) solution on the first nonwoven fabric layer; Forming a nanofiber layer by electrospinning any one of polyurethane (PU) solutions, and e`) coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer and the lower surface of the second nonwoven fabric layer with a roller. And, f`) winding the nanofiber layer and the second nonwoven layer on a paper tube or drum, respectively, and then leaving them at room temperature for 2 to 6 hours to allow the ashes coated aqueous adhesive to penetrate into the nanofiber layer and the second nonwoven layer, g`) finishing coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer with a roller, and h`) passing the nanofiber layer and the second nonwoven fabric layer between upper and lower rollers heated to a temperature of 60 to 90 ° C. to perform thermal compression and bonding. and i`) completely drying at room temperature for 24 to 96 hours to obtain a nanofiber filter.

Instead of completely drying at room temperature for 24 to 96 hours to obtain a nanofiber filter, drying by heating in a drying room at 60 to 90 ° C for 12 to 24 hours, followed by 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 amount of coating (application) of the water-based adhesive may be 8 to 30 g/m 2 .

The water-based adhesive may have a glass transition temperature (Tg value) of -25 to 0°C.

It may further include 1 to 10% by weight of adipic dihydrazide (ADIPIC DIHYDRAZIDE) mixed with the aqueous adhesive.

It further includes 2 to 8% by weight of a water repellent mixed with the water-based adhesive, but the water repellent may be an environmentally friendly fluorine-based water repellent of C6 or less or a silicone-based water repellent.

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

It includes a nanofiber filter using a non-woven fabric manufactured by at least one of the above manufacturing methods.

The nanofiber filter includes a first nonwoven fabric layer, a nanofiber layer electrospun and bonded to the upper surface of the first nonwoven fabric layer with a polyvinylidene fluoride (PVDF) solution, and a first bonded to the upper surface of the nanofiber layer 2 layers of non-woven fabric.

The nanofiber filter includes a first nonwoven fabric layer, a nanofiber layer electrospun and bonded to the upper surface of the first nonwoven fabric layer with a polyurethane (PU) solution, and a second nonwoven fabric layer bonded to the upper surface of the nanofiber layer. includes

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

The basis weight of the first nonwoven fabric layer may be 10 to 50 gsm.

The basis weight of the second nonwoven fabric layer may be 10 to 100 gsm.

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

The present invention can obtain excellent effects as a filter by filtering fine dust viruses, etc., and volatile organic compounds (VOC), formaldehyde, acetaldehyde, etc. are not detected, so only objects or articles (face masks, coatings) applied to the human body Rather, it has an effect that can be applied to various objects.

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

In the present invention, the 'differential pressure', which is the difference in pressure before and after passing through the nanofiber layer 2, is maintained at 1.4 to 5 tablets, which is very comfortable for breathing.

In addition, since general MB filters (or HEPA filters) adsorb and collect fine dust in an electrostatic manner, they are weak against moisture and moisture, so when worn for a long time, there are problems such as reduced performance and shrinkage, but the nanofiber filter of the present invention It is a physical method in which dense nano-scale fiber strands are entangled and filtered, and it blocks harmful substances such as dust and dust in the air, gas, germs, pathogens, fungi, bacteria, and viruses, so it is hardly affected by moisture or moisture. In addition, in the safety test, various harmful components are not detected or are below the standard value, so there is an effect that can be used safely.

In the present invention, since the multi-layered nanofiber filter is well bonded by a water-based adhesive harmless to the human body, there is an effect that it can be usefully used as a human body covering such as a mask, a hat, and gloves.

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

The present invention is harmless to the human body because heavy metals and other harmful substances and formaldehyde, etc. are not detected, and germs, fungi, bacteria, viruses, etc. are blocked and killed in a short time by antibacterial substances.

The present invention is a very useful invention that has effects such as preventing transmission of viruses, bacteria, germs, pathogens, etc. by saliva or droplets.

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 one 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: Scanning electron microscope image showing the nanofibrous layer in the present invention (magnification of 5,000).
Figure 5: A scanning electron microscope image (magnification of 10,000) showing the nanofibrous layer in the present invention.
Figure 6: Blank picture of strain 1 in the antibacterial activity test of the present invention.
Figure 7: Photograph of the test result of strain 1 in the antibacterial activity test of the present invention (18 hours).
Figure 8: Blank picture of strain 2 in the antibacterial activity test of the present invention.
Figure 9: A photograph of the test results of strain 2 in the antibacterial activity test of the present invention (18 hours).

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 described with the same reference numerals as much as possible, and specific descriptions of related well-known configurations or functions are omitted so as not to obscure the subject matter of the present invention. In addition, the accompanying drawings Matters expressed in may be different from the form actually implemented in the drawings schematically for easily explaining the embodiments of the present invention.

1 illustrates the layer structure of a nanofiber filter using the nonwoven fabric of the present invention, a first nonwoven fabric layer (1), and polyvinylidene fluoride (PVDF) on the upper surface of the first nonwoven fabric layer (1) It includes a nanofiber layer 2 that is electrospun and bonded with a solution or a polyurethane (PU) solution, and a second nonwoven fabric layer 3 that is bonded to the upper surface of the nanofiber layer 2.

The nanofiber layer 2 is formed with nano-sized porous pores that are smaller than fine particles and larger than air, so that fine dust, yellow dust, pollen, dust including fine particles, particulate harmful substances, mist, dust In addition, infectious agents such as various germs, pathogens, fungi, bacteria, and viruses, and/or droplets containing them are effectively blocked.

The nonwoven fabric constituting the first and second nonwoven fabric layers (1) and (3) is made into a felt shape by arranging fibers in parallel or in an irregular direction without going through a weaving process, bonding with a synthetic resin adhesive or combining them by thermal compression. It is made of felt, resin-bonded nonwoven fabric, needle punch, spunbond, spun lace, embossed film, wet nonwoven fabric, meltblown, and the like.

The melt blown filter (MB filter) is a non-woven fabric filter made by a manufacturing method in which thermoplastic polymers such as PET and PP (polypropylene) are melted and extruded and spun through a nozzle. have the same structural form as It is also a material widely used for industrial and medical purposes, and is a key raw material used as an internal filter for medical and health masks distributed on the market, including KF masks. Melt blown (melt-spinning) is a method of blowing melted polypropylene raw material in thread form through a nozzle with very small holes. It is pressed while passing between two rollers to become a non-woven fabric.

The first and second nonwoven fabric layers 1 and 3 are adhered or fixed to the upper and lower surfaces of the nanofiber layer 2 to sufficiently protect the nanofiber layer 2 and maintain breathability and durability.

In the above, the first nonwoven fabric layer 1 introduced into the electrospinning device (not shown) is the second nonwoven fabric layer 3 so that the electrospinning and nanofiber layer 2 are efficiently formed while the contact area is enlarged and uniformly fixed. ) is more densely formed.

For example, the basis weight of the first nonwoven fabric layer 1 may be 10 to 50 gsm, and the basis weight of the second nonwoven fabric layer 3 may be 10 to 100 gsm.

The first and second nonwoven fabric layers (1) and (3) are polyvinylidene fluoride (PVDF), olefin-based polypropylene (PP), polyurethane (PU), polyvinyl acrylate (PVA), polyacrylic One main raw material selected from the group consisting of ronitrile (PAN), polylactic acid (PLA), polyelactide (PLLA), polyethersulfone (PES), polyamide (PA) and gelatin, and dimethylacetamide (DMAC), dimethyl fluoro (DMF), dimethyl sulfoxide (DMSO), chlorobenzene (CB), trichloroethanol (TCE), trifluoroethylene (TFE), tetrahydrofuran (THF), methyl ethyl ketone ( MEK), toluene, xylene, formic acid, acetic acid, and one or more solvents selected from the group consisting of water may be extruded at a mixing ratio of 8 to 20% by weight: 92 to 80% by weight.

The first and second nonwoven fabric layers 1 and 3 may be spunbond nonwoven fabrics.

The coating amount (coating amount) of the aqueous adhesive coated on the first and second nonwoven fabric layers (1) (3) and the nanofiber layer (2) is 8 to 30 g/m 2 . If the coating amount of the water-based adhesive is less than 8 g / m 2, the desired adhesive strength cannot be obtained, and if the coating amount exceeds 30 g / m 2, it is not only wasteful, but also the nanofiber layer 2 and the nanocell are broken (brittle ), may be damaged and/or destroyed, which is undesirable.

The first nonwoven fabric layer 1, the nanofiber layer 2, and the second nonwoven fabric layer 3 are bonded with an environmentally friendly water-based adhesive that is harmless to the human body. The water-based 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.

Figure 2 shows a method for manufacturing a nanofiber filter according to an embodiment of the present invention, after the first nonwoven fabric layer 1 is put into the electrospinning apparatus (step S1), and then the first nonwoven fabric layer 1 is placed on the polyvinylidene A fluoride (PVDF) solution or a polyurethane (PU) solution is electrospun to form a nanofiber layer 2 (step S2), and the top surface of the nanofiber layer 2 and the bottom surface of the second nonwoven fabric layer 3 After first roll coating the eco-friendly water-based adhesive with a roller (step S3), the nanofiber layer (2) and the second nonwoven fabric layer (3) coated with the eco-friendly water-based adhesive are wound on a paper tube or drum, respectively, and then 2~ Allowed to stand at room temperature for 6 hours so that the first roll coated water-based adhesive penetrates the nanofiber layer 2 and the second nonwoven fabric layer 3 sufficiently (Step S4), and the upper surface of the nanofiber layer 2 Finish roll coating of the eco-friendly water-based adhesive with a roller (step S5), and the first nonwoven fabric layer (1), the nanofiber layer (2) coated with the eco-friendly water-based adhesive, and the second non-woven fabric layer (3) It is passed between the upper and lower rollers heated at a temperature of 90 ° C., thermally compressed and bonded (step S6), and completely dried at room temperature for 24 to 96 hours to obtain a nanofiber filter (step S7).

Instead of completely drying at room temperature for 24 to 96 hours (step S7), a 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).

Figure 3 shows a method for manufacturing a nanofiber filter of another embodiment of the present invention, first roll coating an eco-friendly water-based adhesive on the upper surface of the first nonwoven fabric layer 1 with a roller (step S11), and eco-friendly The first nonwoven fabric layer 1 coated with the water-based adhesive is naturally dried at room temperature so that the moisture content of the first nonwoven fabric layer 1 is maintained at 40 to 60% (step S12), and then the first nonwoven fabric layer 1 is put into the electrospinning device (step S13) , Electrospinning a polyvinylidene fluoride (PVDF) solution or a polyurethane (PU) solution on the first nonwoven fabric layer (1) to form a nanofiber layer (2) (step S14), the top of the nanofiber layer (2) Secondary roll coating of the eco-friendly water-based adhesive on the bottom surface of the cotton and the second non-woven fabric layer 3 with a roller (step S15), and the nanofiber layer 2 and the second non-woven fabric layer (3) coated with the eco-friendly water-based adhesive ) is wound on a paper tube or drum, respectively, and then left at room temperature for 2 to 6 hours to allow the ashes coated water-based adhesive to sufficiently permeate into the nanofiber layer 2 and the second nonwoven fabric layer 3 (step S16), and the nanofiber layer (2) finish roll coating with a roller on the upper surface of the eco-friendly water-based adhesive (step S17), and the first non-woven fabric layer (1), the nanofiber layer (2) coated with the eco-friendly water-based adhesive, and the second non-woven fabric The layer (3) is passed between upper and lower rollers heated at a temperature of 60 to 90 ° C. to be thermally compressed and bonded (step S18), and completely dried at room temperature for 24 to 96 hours to obtain a nanofiber filter (step S19). .

Instead of completely drying at room temperature for 24 to 96 hours (step S19), a 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 EVA (ethylene vinyl acetate) copolymer and a water-based acrylic copolymer, and becomes transparent after drying (or curing) without leaving traces.

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 bendability (ductility) of the nanofiber filter is too soft and the shape can be easily deformed, and if the glass transition temperature exceeds 0 ℃, the nanofiber filter becomes hard and worn Since rejection may occur, it is preferable to have a glass transition temperature of -25 ° C to 0 ° C, which is soft and has excellent adhesion.

The EVA copolymer (ethylene-vinyl acetate copolymer) is a polymer obtained by copolymerizing ethylene and vinyl acetate monomers, and is also called ethylene-vinyl acetate copolymer. It has excellent stress cracking resistance and is used as an adhesive for heavy packaging materials and laminate films. 10-20% of EVA is used for the same purposes as soft vinyl chloride, such as foamed products such as sandals and soles, agricultural films, and business stretch films. High-concentration EVA is used as a raw material for adhesives.

The acrylic resin refers to a polymer from esters such as acrylic acid and methacrylic acid, and a representative polymer of methyl methacrylate (methyl methacrylate). It 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 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. It is harmless to the human body because it has the effect of adsorbing and deodorizing components such as volatile organic compounds (VOC) and formaldehyde.

The thiourea (CH ₄ N ₂ S) is an organic compound composed of carbon, nitrogen, sulfur, hydrogen, etc., and is a colorless crystal. The molecular weight of thiourea is 7312, the melting point is 180℃, and the specific gravity is 1405. Soluble in water and ethanol, but almost insoluble in ether. The aqueous solution is neutral and tastes bitter. 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 deodorizing effect is excellent.

The urea (CO(NH ₂ ) ₂ ) is an organic compound and is a colorless crystalline substance, and is the final decomposition product of protein metabolism in all mammals and some fish, and is composed of urea, carbamide, and diaminomethanal. It is a substance that has no color or odor and makes columnar crystals. The molecular weight is 60047, the melting point is 1327℃ (1atm), and the specific gravity is 1335. It is a highly polar substance, so it is soluble in water and alcohol, but insoluble in ether.

The boric acid (H ₃ BO ₃ ) is an oxygen acid produced by hydration of boron oxide, and includes orthoboric acid, metaboric acid, tetraboric acid, and the like. Orthoboric acid is a raw material for borosilicate glass and ceramic glaze, and also promotes the dissolution of injections. Orthoboric acid is a colorless, transparent or white glossy scaly crystal that has no odor and has a peculiar taste. Melting point is 184~186℃, specific gravity is 149.

The nanofiber filter of the present invention removes volatile organic compounds (VOC), formaldehyde, acetaldehyde, odor, can be safely used in any climatic conditions, and prevents the propagation of various molds and bacteria by antibacterial agents, and prevents bacteria and pathogens , bacteria, viruses, etc. are killed in a short time.

The present invention may further include 1 to 10% by weight of an antibacterial substance mixed with the aqueous adhesive. The antibacterial substance may be adipic dihydrazide (AHD), 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 are formed.

Adipic dihydrazide molecule has a total of 25 chemical bonds, which consist of 11 non-hydrogen bonds, 2 multiple bonds, 5 single bonds, 2 double bonds and 2 N-hydrazine, and its appearance is white. It is liquefied while being mixed with powder or water-based adhesive, and it gives antibacterial function to the coated nanofiber filter and greatly contributes to reducing formaldehyde.

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

Polyvinylidene fluoride (PVDF) or polyurethane (PU) 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 liquid.

In addition, the polyvinylidene fluoride (PVDF) and polyurethane (PU) that are electrospun when constituting the nanofiber layer 2 are ferroelectric materials that not only have their own static charge, but also increase the electrostatic charge by electrospinning. Fine dust and the like are collected more effectively.

Figure 4 is an image taken at a magnification of 5,000 times the nanofiber layer 2, Figure 5 is an image taken at a magnification of 10,000 times the nanofiber layer (2).

In FIG. 5, it can be seen that nanofiber yarns with diameters of 125.5 nm, 150.6 nm, 200.8 nm, and 251.0 nm and nanofiber yarns around them are composed of a web form, and pores formed between nanofiber yarns (nanocells) ) is in the range of at least 50 nm to 1 μm, and ventilation and respiration are achieved while 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 nanofibrous yarn diameter of the nanofiber layer 2 may be 100 nm to 300 nm. When the diameter of the nanofiber yarn is larger than 300 nm, the ultra-thinization is not sufficient and the fiber surface area is lowered, resulting in a decrease in the collection efficiency as a filter medium for filtering, making it difficult to remove fine dust and the like. As the density increases, the differential pressure increases, and the strength decreases and production is difficult.

When the present invention is applied to a face mask and worn, not only fine particles such as air dust, fine dust, yellow dust, pollen, and dust, but also biological transmission such as bacteria and pathogens, molds, biological particles, bacteria, viruses, and droplets (MERS / It can be usefully used as various filters, masks, coatings, etc. to remove SARS/coronavirus infection-19 (Corona-19) or harmful things.

In addition, the colors of the first nonwoven fabric layer 1 and the second nonwoven fabric layer 3 can be implemented with various colors by selecting various colorants (pigments, dyes, etc.).

The polyvinylidene fluoride (PVDF) is a type of fluororesin polymer and has excellent mechanical properties to make a highly crystalline resin. It also has a high dielectric constant and special properties such as piezoelectricity.

The characteristics of polyvinylidene fluoride (PVDF) polymer are that it has strong mechanical strength among fluororesins, especially high abrasion resistance, and excellent chemical resistance. It is affected by amines, esters and ethers. In addition, it has low ultraviolet and radiation deterioration, excellent weather resistance and electrical insulation, and has great piezoelectric properties. Its dielectric constant is smaller than that of inorganic piezoelectric materials, but its piezoelectric voltage strength is high, it is light and flexible, so it can withstand shock bending well, and it is easy to match with water or living organisms because it has low mechanical impedance. Doesn't break even on large inputs. It has a low permittivity and specific heat, high pyroelectric sensitivity, and low thermal diffusivity, so it has excellent spatial resolution.

Polyvinylidene fluoride (PVDF) is used for mechanical parts such as barking, gaskets, pipe joints, diaphragm containers, printed circuit boards, insulated terminals, socket capacitor films, window frame sealing materials for high-rise buildings, sheet materials, metal plate linings, speakers, Headphones, cartridges, ultrasonic microphones, ultrasonic microscopes, measurement sensors, strain gauges, pressure sensors, and the like are examples.

The polyurethane (PU) is produced by the reaction of polyisocyanate (-NCO) and polyol (-OH), and is applied for various purposes due to the excellent physical properties that only urethane has, such as adhesives, fillers, textile products, shoes, It is used to manufacture products that can always be found around our lives, such as beds, refrigerators, automobiles, sofas, building materials, and flooring. In addition, its application is expanding to eco-friendly and medical functional materials such as biofilters for organic waste treatment, blood and plasma filters, and wet dressing materials.

In the present invention, the nanofiber layer 2 is obtained by electrospinning a polyvinylidene fluoride (PVDF) solution or a polyurethane (PU) solution.

Of course, the nanofiber layer 2 may be obtained by mixing and electrospinning a polyvinylidene fluoride (PVDF) solution and a polyurethane (PU) solution in an appropriate ratio.

On the other hand, 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, and the particles are induced to the interface between the air layer and the surface of the solution. A force opposite to the surface tension is generated. At this time, the sprayed solution is collected in the collector by a potential difference with the metal collector on the opposite side while overcoming the surface tension at a threshold voltage or higher. According to this principle, it is possible to manufacture nanofibers through a polymer solution.

In the case of manufacturing a nanofiber web with polyvinylidene fluoride (PVDF) or polyurethane (PU) through the electrospinning method, after the polymer solution (+) sprayed during the electrospinning process is solidified, the electrode (integrator) (- poles), the dipole arrangement (C-F) inside the polyvinylidene fluoride (PVDF) or polyurethane (PU) fibers occurs simultaneously by the electric field generated when the fibers are collected, so a separate polarization treatment process is not required. PVDF with a high β crystal content can be produced.

On the other hand, since general MB filters (or HEPA filters) adsorb and collect dust in an electrostatic way, they are weak against moisture and moisture, so when worn for a long time, their performance deteriorates and shrinks. It blocks ultra-fine dust or viruses through a physical method in which the fiber strands are entangled and filtered out, so it is hardly affected by moisture or humidity, and various harmful ingredients are not detected or are below the standard level in safety tests, so you can use it with confidence. There is an effect.

In addition, polyvinylidene fluoride (PVDF) or polyurethane (PU), which is electrospun when forming the nanofiber layer 2, is a ferroelectric material and has its own electrostatic charge. Dust and the like are collected more effectively.

Table 1 below is a table of PBBs (Polybrominated biphenyls) detection amount test results for the nanofiber filter of the present invention, and it can be seen that various harmful components are detected below the detection limit and are safe even when used 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 PBDEs (Polybrominated diphenyl ethers) detection test result table, and various harmful components are detected or not detected below the detection limit (less than 5 mg / kg), so it can be seen that it is safe even when used 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 3 below is a test result of the amount of phthalate detected, and various harmful components are detected below the detection limit of 0.01%, indicating that it is safe even when used in the human body.

Test Items Result (Unit: %) Test Methods detection limit DEHP less than 0.01
IEC 62321-8:2017 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 table of test results for the amount of formaldehyde detected, and it is not detected, so it can be seen that it is safe even when used in the human body.

Test Items Result (unit: mg/kg) Test Methods detection limit formaldehyde not detected KS K ISO 14184-1:1998 16 (mg/kg)

Table 5 below is a test result table of the 8 major heavy metals detected, and it is detected (not detected) below the detection limit, so it can be seen that it is safe even when used in the human body.

Test Items result
(Unit: mg/kg) Test Methods limit of quantification
(Unit: mg/kg) Lead [Pb] non-detection



ISO 8124-3 : 2010 5 Cadmium [Cd] non-detection 5 Chromium [Cr] non-detection 2 Antimony [Sb] non-detection 5 arsenic [As] non-detection 2 barium [Ba] non-detection 5 Selenium [Se] non-detection 5 Mercury [Hg] non-detection 2

Table 6 below is a quantitative test result table for other harmful substances, and it can be seen that it is safe even when used in the human body because it is below the quantification limit or is 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 confirmation [Notice No. 2019-70 (2019.12.31.) of the National Institute of Environmental Research] One Benzisothiazolinone
(BENZISOTHIAZOLIONE) non-detection One 2-Octyl-3(2H)isothiazolone
(OIT) non-detection One 5-Chloromethylisothiazolinone
(5-CHLOROMETHYLISOTHIAZOLIONE) non-detection National Institute of Environmental Research Notice No. 2019-70 (2019.12.31.) One

* Non-detection = less than quantification limit

Table 7 below is a test result of the detection amount of dimethylformamide, which is used as one of the polar organic solvents and is used as a solvent for various chemical reactions. It has been detected and it can be known that it is safe even when used in the human body. The dimethylformamide is used as a spinning agent for synthetic fibers, and stimulates the skin, eyes, and mucous membranes, and causes liver failure when inhaled for a long time.

Test Items Result (unit: mg/kg) Test Methods detection limit formaldehyde less than 10 GC-MSD analysis 10 (mg/kg)

* Analyzed by GC-MSD after extracting the specimen with methanol

According to the above Tables 4 to 7, the nanofiber filter prepared according to the embodiments of the present invention, heavy metals, volatile organic compounds (VOCs), volatile aromatic hydrocarbons (VACs), total volatile organic compounds (TVOC), toluene, formaldehyde It was found that none of the items were detected or a small amount was detected at 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 is applied to various filters and masks, etc. was satisfied.

Table 8 below is a table of results of the UV blocking rate test, and it can be seen that the UV blocking rate is excellent.

Test Items Results (unit: nm) measuring device wavelength interval Ultraviolet (UV-R) blocking rate 65.8/47.8/58.2/52.3 UV-VIS-NIR Spectrophotometer
(Perkin Elmer_Lambda 1050 with 150 mm InGaAs int. Sphere) 5 nm Ultraviolet (UV-A) blocking rate 58.5/40.7/51.0/44.8 5 nm Ultraviolet (UV-B) blocking rate 90.0/70.6/84.2/76.7 5 nm

* Wavelength range UV-R: 290~400nm, UV-A: 315~400nm, UV-B: 290~315nm

* Due to the deviation of the data for each part, individual values are indicated.

Table 9 below is a transmittance test result table of the nanofiber filter of the present invention. As a result of testing for 30 seconds three times using a filter tester (filter tester (Lorenz FMP03)) and paraffin oil in the form of aerosol, the transmittance of the nanofiber filter was 2.7%. , and the filter efficiency was 97.3%, which was very good.

transmittance 2.7% efficiency 97.3%

* Test equipment: filter tester (Lorenz FMP03)

* Aerosol form: paraffin oil

* Aerosol average 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 before and after passing through the nanofiber layer 2, was measured as 1.4, indicating that it is very comfortable 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 in the case of KF-80, the differential pressure is 6 to 7, making it difficult to breathe, whereas the nanofiber filter of the present invention has a pressure difference of about 1.4 to 5. relaxing.

Table 10 below is a test result table for liquid resistance, and it can be seen that water does not penetrate into the nanofiber layer 2 within 30 minutes, and when the present invention is applied to a face mask, etc., scattering or emission through the respiratory tract of the mask wearer It can be seen that it is possible to block the droplets, and conversely, it is possible to prevent the intrusion of external droplets into the respiratory tract through the mask.

Liquid resistance test method After putting 100 ml of water in a 250 ml beaker, fix the sample on it with the lining facing the beaker using a rubber band or other tool, and then slowly turn the beaker over and fix it with a space of a certain height on the floor.
Place a piece of paper under the beaker and let stand for 30 minutes. result No water penetration within 30 minutes

Table 11 below is an ammonia deodorization performance test result table, and it can be seen that the deodorization rate is excellent at 10.8%.

Test Items Result (Unit: %) Test Methods ammonia 10.8 gas detection tube
(FITI Test Guideline FTM-5-2:2004)

* Test piece: 100cm2 (10cm × 10cm)

* Gas bag: 5L

* Gas volume in gas bag: 3L

* Measurement time: after 2 hours

* Initial concentration: Ammonia (100 ppm)

* Deodorization rate (%) : ((Cb - Cs)/(Cb) × 100

- Cb: BLANK, concentration of test gas remaining in the test gas bag after 2 hours

- Cs: Sample, test gas concentration remaining in the test gas bag after 2 hours

Table 12 below shows an antimicrobial test (KS K0693) in which the water-based adhesive of the present invention is provided with an antibacterial function by including 1 to 10% by weight of ADIPIC DIHYDRAZIDE (AHD), an antibacterial substance. : 2016) As a result table, the sample used for the antimicrobial test is the nanofiber layer (2) of the nanofiber filter. tested.

division Number of 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 12, 'strain 1' is Staphylococcus aureus ATCC 6538, 'strain 2' is Klebsiella pneumonian ATCC 4352, the standard cloth is 'nanofibrous layer (2)', and the nonionic surfactant is 0.05 % is added, and '<' means less than a number.

6 and 7 are antibacterial test photos for strain 1 (Staphylococcus aureus ATCC 6538), FIG. 6 is a sample (Blank) bacterial solution (1.8×10 ⁴ ) photo, and FIG. 7 is a photo of the test result after 18 hours. As a result, the number of bacteria in 'strain 1' was less than 10 and 99.9% was removed, indicating that the antibacterial activity was very excellent.

8 and 9 are antibacterial test photos for strain 2 (Klebsiella pneumonian ATCC 4352), FIG. 8 is a photo of the bacterial solution (1.8×10 ⁴ ) of the sample (Blank), and FIG. 9 is a photo of the test results after 18 hours. As a result, the number of bacteria in 'strain 2' was 1.2 × 10 ⁴ and 99.9% was removed, indicating that the nanofiber filter of the present invention has excellent antimicrobial activity.

As can be seen from the above antibacterial test results, in the case of the 'nanofiber layer (2)' sample containing the antibacterial substance ADIPIC DIHYDRAZIDE (AHD), the initial bacterial count of strains 1 and 2 was 1.8 × It was 10 ⁴ , but after 18 hours, almost all of them were removed, indicating that the antibacterial activity was very good.

The present invention can be safely used for various objects because various bacteria, pathogens, microorganisms, viruses, etc. .

The adipic dihydrazide (AHD: ADIPIC DIHYDRAZIDE) maintains very excellent antibacterial and sterilizing power continuously, and is very economical because it is antibacterial and sterilizing without physical or electrical sterilization or washing.

The nanofiber filter according to the present invention can be applied to various electronic products such as face masks, clothing, dustproof clothing, protective clothing, dustproof nets, air purifiers, air conditioners, automobiles, ventilation air filters, transportation air filters, industrial filters, and clean room facilities. However, the use range 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 are possible within the scope without departing from the technical spirit of the present invention, which is in the technical field to which the present invention belongs. It is self-evident to those skilled in the art.

(1)--First Nonwoven Fabric Layer (2)-Nanofiber Layer (3)--Second Nonwoven Fabric Layer

Claims (10)

a) putting the first nonwoven fabric layer into an electrospinning device;
b) electrospinning a solution of either a polyvinylidene fluoride (PVDF) solution or a polyurethane (PU) solution on the first nonwoven fabric layer to form a nanofiber layer;
c) first coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer and the lower surface of the second nonwoven fabric layer with a roller;
d) winding the nanofiber layer and the second nonwoven fabric layer on a paper tube or drum, and then leaving them at room temperature for 2 to 6 hours so that the first coated aqueous adhesive penetrates into the nanofiber layer and the second nonwoven fabric layer;
e) finishing coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer with a roller;
f) thermally compressing and bonding the first nonwoven fabric layer, the nanofiber layer coated with the eco-friendly water-based adhesive, and the second nonwoven fabric layer between upper and lower rollers heated to a temperature of 60 to 90 ° C;
g) completely drying at room temperature for 24 to 96 hours; Including,
The water-based adhesive is a nanofiber filter using a non-woven fabric containing 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. manufacturing method. a`) pre-coating an eco-friendly water-based adhesive on the upper surface of the first nonwoven fabric layer with a roller;
b`) naturally drying at room temperature so that the moisture content of the first nonwoven fabric layer coated with the rough coating is maintained at 40 to 60%;
c`) putting the first nonwoven fabric layer into an electrospinning apparatus;
d`) electrospinning a solution of either a polyvinylidene fluoride (PVDF) solution or a polyurethane (PU) solution on the first nonwoven fabric layer to form a nanofiber layer;
e`) coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer and the lower surface of the second nonwoven fabric layer with a roller;
f`) winding the nanofiber layer and the second nonwoven fabric layer on a paper tube or drum, and then leaving them at room temperature for 2 to 6 hours so that the ashes coated water-based adhesive penetrates into the nanofiber layer and the second nonwoven layer;
g`) finishing coating an eco-friendly water-based adhesive on the upper surface of the nanofiber layer with a roller;
h`) thermally compressing and bonding the nanofiber layer and the second nonwoven layer by passing them between upper and lower rollers heated to a temperature of 60 to 90° C.;
i`) completely drying at room temperature for 24 to 96 hours to obtain a nanofiber filter; Including,
The water-based adhesive is a nanofiber filter using a non-woven fabric containing 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. manufacturing method. according to claim 1 or claim 2;
Instead of step g) or i`) of obtaining a nanofiber filter by completely drying at room temperature for 24 to 96 hours, drying by heating in a drying room at 60 to 90 ° C for 12 to 24 hours, then drying completely at room temperature for 12 to 24 hours to obtain nanofibers obtaining a filter;
Nanofiber filter manufacturing method using a non-woven fabric comprising a. according to claim 1 or claim 2;
Nanofiber filter manufacturing method using a non-woven fabric, characterized in that the coating amount of the water-based adhesive is 8 ~ 30g / ㎡. delete according to claim 1 or claim 2;
The VOC reducing agent is a nanofiber filter using a nonwoven fabric, 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 manufacturing method. according to claim 1 or claim 2;
Nanofiber filter manufacturing method using a nonwoven fabric further containing 1 to 10% by weight of adipic dihydrazide (ADIPIC DIHYDRAZIDE). according to claim 1 or claim 2;
Further comprising 2 to 8% by weight of water repellent, but the water repellent is a nanofiber filter manufacturing method using a non-woven fabric, characterized in that either an environmentally friendly fluorine-based water repellent or a silicon-based water repellent. A nanofiber filter using a nonwoven fabric manufactured by the manufacturing method of claim 1 or claim 2.
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