JP7510250B2 - Porous composite powder for removing fine dust and its manufacturing method - Google Patents

Description

This specification discloses a porous composite powder with excellent fine dust removal properties and a method for producing the same.

When dust accumulates in the body, it can weaken the body's immune system and induce various diseases such as heart disease and respiratory disease. It can also cause bronchial narrowing, and if inhaled for a long period of time, it can increase the prevalence of asthma and lung disease, as well as early mortality.

The skin is the outermost part of the body that comes into direct contact with dust and acts as a barrier between the organism and the environment, and frequent exposure to pollution weakens this barrier function. Fine dust, in particular, is 20 times smaller than a hair follicle and can easily penetrate the skin. In fact, air pollutants such as fine dust are known to have serious effects on skin health. In the short term, they can cause premature aging, dehydration, and increased fine lines and wrinkles, and in the long term, they can cause irreversible skin damage that causes the skin to lose its ability to protect itself from environmental elements and can even lead to serious diseases such as skin cancer.

In particular, while most of the dust that accumulates on the skin can be removed using various existing cleansers, it is not easy to remove the fine dust that has penetrated into the pores. Therefore, research is needed on functional composite powder structures that can effectively remove the fine dust that remains in the pores and is harmful to the skin and can cause fatal damage to the human body. In addition, since the raw material acts inside the pores, it is important to select a biocompatible material that is non-irritating and safe.

Korean Patent Publication No. 2014-0118504

In one aspect, the object of the present invention is to use a porous composite powder to effectively absorb sebum and other particles that contain fine dust adhering to the skin into the porous composite powder.

In another aspect, the object of the present invention is to effectively remove fine dust particles remaining on the skin and in pores using a porous composite powder containing magnetic particles and a magnetic applicator.

In another aspect, the object of the present invention is to produce a porous composite powder for removing fine dust, which is uniformly impregnated with magnetic particles, by a simple process.

In one aspect, the present invention provides a porous composite powder for removing fine dust, comprising a polymer and magnetic particles impregnated in the polymer.

In another aspect, the present invention provides a composition comprising the porous composite powder described above.

In another aspect, the present invention provides a method for removing fine dust, comprising the steps of applying the composition described above onto the skin and detaching the porous composite powder from the skin using a magnetic applicator.

In another aspect, the present invention provides a method for producing the porous composite powder for removing fine dust, comprising the steps of preparing a solution containing a polymer, dispersing magnetic particles in the solution containing the polymer, and spray-drying the solution in which the magnetic particles are dispersed.

In one aspect, the porous composite powder for removing fine dust according to the present invention is made by uniformly impregnating a porous polymer with magnetic particles, sucking the sebum containing fine dust into the pores, and then easily detaching it from the skin using a magnetic applicator, thereby effectively removing fine dust remaining on the skin and in the pores.

FIG. 2 is a schematic diagram of a spray drying process for producing the fine dust porous composite powder according to the present invention. 1 is an electron microscope image of the porous composite powder according to the present invention. 2b is an electron microscope image showing the surface of FIG. 2a at a further magnification. 1 is a photograph of an oil absorption measuring device (S-500, manufactured by Asahi Souken Co., Ltd.) for measuring the oil absorption of the porous composite powder according to the present invention. 3b is a photograph of a part of the oil absorption measurement equipment of FIG. 3a. 1 shows the results of measuring the oil absorption (ml/g) of general iron oxide and the porous composite powder (PLGA+iron oxide) according to the present invention. 1 is an electron microscope image of the porous composite powder according to the present invention. 4 is an EDX mapping image after the porous composite powder according to the present invention is sufficiently absorbed into a solution containing Pb. 1 is an EDX mapping image after the porous composite powder according to the present invention is sufficiently absorbed into a solution containing Cd. 1 is an EDX mapping image after the porous composite powder according to the present invention is sufficiently absorbed into a solution containing Hg. 1 is an EDX mapping image after the porous composite powder according to the present invention is sufficiently absorbed into a solution containing As. 4 is an EDX mapping image after the porous composite powder according to the present invention is sufficiently absorbed into a solution containing Sb. This is a photograph of the surface of the pore mimetic taken under a microscope after rubbing the surface with tissue 30 times. The surface of the pore mimic was rubbed 30 times with a magnet (1000 Gauss) wrapped in tissue, and then the surface of the pore mimic was photographed under a microscope. FIG. 2 is a diagram simply illustrating the characteristics of the porous composite powder for removing fine dust according to the present invention. FIG. 2 is a schematic diagram showing the mechanism by which the porous composite powder according to the present invention removes fine dust (fine dust shuttle). 1 shows the results of measuring the magnetic properties of the porous composite powder according to the present invention as a function of the iron oxide content. 1 is a graph plotting the relationship between pore diameter and logarithm of differential penetration for a porous composite powder according to the present invention. 4 shows the results of measuring the porosity of the porous composite powder according to the present invention.

Definition of Terms In this specification, the _term "magnetic particles" refers to any particles having magnetism, such as ferromagnetic (Ferromagnetic, Fe, _{Ni, Co, etc.), ferrimagnetic (Ferrimagnetic, Fe2O3 , MnFe2O4} , _BAO6Fe2O3 , etc.), _paramagnetic (Paramagnetic, Al, Ti, Cu alloy, etc.), superparamagnetic (Superparamagnetic, _{Fe3O4 ,} etc.), etc., without being limited by the degree or type of magnetism. In addition, the magnetic particles may be impregnable.

In this specification, "dust" is a general term for fine particles mixed in the air, and generally refers to suspended matter having a particle size of 10 mm or less. In particular, particles having a particle size of 10 μm or less are called fine dust, particles having a particle size of 2.5 μm or less are called ultrafine dust, and particles having a particle size of 0.1 μm or less are called extremely fine dust. Here, particle size may refer to the average particle size of each particle of fine dust. Dust is a material that includes natural substances such as sand, soil, and pollen, or substances derived from industrial processes such as carbon, carbon combustion products, metal salts, and heavy metals. Dust may take the form of fumes, mist, smoke, steam, or smoke.

In this specification, "particle size" refers to the diameter of a particle, and the defined particle size range refers to the range of diameters of each individual particle.

In this specification, when a part "contains" a certain component, this does not mean to exclude other components, but may further include other components, unless otherwise specified.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS The present invention will now be described in detail.

Porous Composite Powder for Removing Fine Dust According to an exemplary embodiment of the present invention, there is provided a porous composite powder for removing fine dust, comprising a polymer and magnetic particles impregnated in the polymer.

Conventionally, it has been possible to use porous silica or porous polymer particles to suck up fine dust particles present in pores together with sebum, but a fatal problem is that once porous particles have entered the pores, it is extremely difficult to remove them again.

To overcome this, the inventors invented a porous composite powder for removing fine dust, which is made by uniformly impregnating a porous polymer with magnetic particles, and which penetrates into the pores and sucks in fine dust mixed with sebum through capillary action, and then uses a magnetic applicator to easily remove the porous composite powder from the pores and safely detach it from the skin (Figure 8).

Specifically, by using spray drying technology, it is possible to produce a composite powder in which magnetic particles are uniformly impregnated into a porous polymer in a single process. In the case of the polymer, a biodegradable polymer can be used to maximize skin affinity, which is a major advantage of this technology (Figure 7).

In one embodiment, the polymer may be one or more selected from the group consisting of polymethyl methacrylate (PMMA), polystyrene (PS), polyvinylpyrrolidone (PVP), polycaprolactone (PCL), polylactic acid (PLA), and lactic acid-glycolic acid copolymer (PLGA), and is not particularly limited as long as it is soluble in dichloromethane, ethanol, acetone, etc.

In one embodiment, the polymer may be a biodegradable polymer, and may be one or more selected from the group consisting of polycaprolactone (PCL), polylactic acid (PLA), and polylactic acid-glycolic acid copolymer (PLGA), and may be preferably polylactic acid-glycolic acid copolymer (PLGA). In the present invention, by applying a biodegradable polymer, the issues of plastic microbeads can be eliminated and biocompatibility with the skin can be improved despite acting inside pores.

In one embodiment, the magnetic particles may be one or more selected from the group consisting of _Fe , _Ni , Co, _MnFe2O4 , _BaO.6Fe2O3 , an alloy of Al, an alloy of Ti, an alloy of Cu, and iron oxide, and may be preferably _{Fe3O4 .}

In one embodiment, the impregnation ratio of the magnetic particles based on the total weight of the porous composite powder may be in the range of 50 to 90% by weight, for example, 55% by weight or more, 60% by weight or more, 65% by weight or more, or 70% by weight or more, and 88% by weight or less, 86% by weight or less, 84% by weight or less, 82% by weight or less, or 80% by weight or less. If the impregnation ratio is less than 50% by weight, the porous composite powder that has absorbed sebum from the pores may be difficult to remove due to weak magnetism, and if it exceeds 90% by weight, the magnetism increases but the sebum absorption may decrease.

In one embodiment, the particle size of the porous composite powder may be in the range of 10 to 100 μm, for example, 15 μm or more, 20 μm or more, 25 μm or more, or 30 μm or more, and may be 95 μm or less, 85 μm or less, 80 μm or less, 75 μm or less, 70 μm or less, 65 μm or less, 60 μm or less, 55 μm or less, or 50 μm or less. If the particle size is less than 10 μm, it may be difficult to sufficiently absorb sebum containing fine dust on the skin, and if the particle size exceeds 100 μm, a grainy or foreign body feeling may be felt when actually applied to the skin.

In one embodiment, the pore diameter of the porous composite powder may be 100 nm to 10 μm, for example, 150 nm or more, 200 nm or more, 250 nm or more, 300 nm or more, 350 nm or more, 400 nm or more, 450 nm or more, or 500 nm or more, and 9 μm or less, 8 μm or less, 7 μm or less, 6 μm or less, 5 μm or less, 4 μm or less, 3 μm or less, 2 μm or less, or 1 μm or less. If the pore diameter is less than 100 nm, it may be difficult to absorb sebum containing fine dust inside the pores, and if it exceeds 10 μm, there is a high possibility that the mechanical strength will decrease and the particles will be easily broken.

In one embodiment, the average pore diameter (4V/A) of the porous composite powder may be 0.01 to 2 μm, for example, 0.05 μm or more, 0.1 μm or more, 0.2 μm or more, or 0.3 μm or more, and 1.7 μm or less, 1.5 μm or less, 1.3 μm or less, 1.1 μm or less, 0.9 μm or less, 0.8 μm or less, 0.7 μm or less, 0.6 μm or less, 0.5 μm or less, or 0.4 μm or less.

In one embodiment, the porosity of the porous composite powder may be 30-80%, for example, 35% or more, 40% or more, 45% or more, 50% or more, 55% or more, 60% or more, and 75% or less, 70% or less, or 65% or less. The porosity refers to the total ratio of pores that can actually absorb sebum including fine dust, and if it is less than 30%, the fine dust removal effect may be negligible, and if it exceeds 80%, the mechanical strength may decrease and the particles may be easily broken.

In one embodiment, the magnetic strength of the porous composite powder may be 30 to 70 emu/g as measured by a magnetometer, for example, 35 emu/g or more, 40 emu/g or more, 45 emu/g or more, or 50 emu/g or more, and 65 emu/g or less, 60 emu/g or less, or 55 emu/g or less. If the magnetic strength is less than 30 emu/g, it may be difficult to remove the porous composite powder according to the present invention that has absorbed sebum including fine dust from the skin, and if it exceeds 70 emu/g, it may be extremely difficult to remove the composite powder from the magnetic applicator.

In one embodiment, the porous composite powder can remove fine dust particles having a particle size of 2.5 μm or less, for example, fine dust particles having a particle size of 2 μm or less, 1.5 μm or less, or 1 μm or less. Even if fine dust particles having a small particle size penetrate into the pores, the porous composite powder according to the present invention can easily remove harmful substances from the skin by sucking in the fine dust particles mixed with sebum in the pores through capillary action and easily removing the fine dust particles from the pores using a magnetic applicator described below.

In an exemplary embodiment of the present invention, a composition for removing fine dust is provided that includes the porous composite powder described above.

In one embodiment, the content of the porous composite powder may be in the range of 30 to 70 wt %, for example, 35 wt % or more, 40 wt % or more, 45 wt % or more, or 50 wt % or more, and 65 wt % or less, 60 wt % or less, or 55 wt % or less, based on the total weight of the composition. If the content is less than 30 wt %, the dust removal effect may be insignificant, and if it exceeds 70 wt %, a foreign body sensation may be felt and may be harmful to the skin.

In one embodiment, the composition may be a cosmetic composition, the cosmetic composition comprising a cosmetically or dermatologically acceptable medium or base. It may be provided in any formulation suitable for topical application, for example in the form of a solution, gel, solid, paste-based anhydrous product, emulsion obtained by dispersing an oily phase in an aqueous phase, suspension, microemulsion, microcapsule, microgranule or vesicular dispersion of ionic (liposome) and non-ionic type, or in the form of a cream, skin, lotion, powder, ointment, spray or conceal stick. These compositions may be prepared by conventional methods in the art. The composition according to the present invention may also be used in the form of a foam or in the form of an aerosol composition further containing a compressed propellant.

The cosmetic composition according to one embodiment of the present invention is not particularly limited in its formulation, and may be formulated into cosmetics such as, for example, softening lotion, astringent lotion, nourishing lotion, nourishing cream, massage cream, essence, eye cream, eye essence, cleansing cream, cleansing foam, cleansing water, cleansing tissue containing the cosmetic composition, pack, powder, body lotion, body cream, body oil, and body essence.

When the dosage form of the present invention is a paste, cream or gel, the carrier component may be animal fiber, vegetable fiber, wax, paraffin, starch, tragacanth, cellulose derivatives, polyethylene glycol, silicone, bentonite, silica, talc or zinc oxide.

When the dosage form of the present invention is a powder or a spray, lactose, talc, silica, aluminum hydroxide, calcium silicate or polyamide powder may be used as a carrier component, and particularly when the dosage form is a spray, it may further contain a propellant such as chlorofluorohydrocarbon, propane/butane or dimethyl ether.

When the dosage form of the present invention is a solution or emulsion, a solvent, solvating agent or emulsifier may be used as a carrier component, such as water, ethanol, isopropanol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butyl glycol oil, glycerol aliphatic esters, polyethylene glycol or fatty acid esters of sorbitan.

When the dosage form of the present invention is a suspension, the carrier component may be a liquid diluent such as water, ethanol or propylene glycol, a suspending agent such as ethoxylated isostearyl alcohol, polyoxyethylene sorbitol ester and polyoxyethylene sorbitan ester, microcrystalline cellulose, aluminum metahydroxide, bentonite, agar or tragacanth.

When the dosage form of the present invention is a surfactant-containing cleanser, the carrier component may be fatty alcohol sorbate, fatty alcohol ether sorbate, sulfosuccinic acid monoester, isethionate, imidazolinium derivative, methyl taurate, sarcosinate, fatty acid amide ether sorbate, alkylamidobetaine, fatty alcohol, fatty acid glyceride, fatty acid diethanolamide, vegetable oil, linolin derivative, or ethoxylated glycerol fatty acid ester.

The cosmetic composition according to one embodiment of the present invention may further include functional additives and ingredients contained in general cosmetic compositions in addition to the porous composite powder. The functional additives may include ingredients selected from the group consisting of water-soluble vitamins, oil-soluble vitamins, polymeric peptides, polymeric polysaccharides, sphingolipids, and seaweed extracts.

The cosmetic composition according to the present invention may further contain, in addition to the functional additives, ingredients contained in general cosmetic compositions, if necessary. Other ingredients that may be contained include oils and fats, moisturizers, emollients, surfactants, organic and inorganic pigments, organic powders, UV absorbers, preservatives, bactericides, antioxidants, plant extracts, pH adjusters, alcohol, colorants, fragrances, blood circulation promoters, cooling agents, antiperspirants, purified water, etc.

In an exemplary embodiment of the present invention, a method for removing fine dust is provided, which includes the steps of applying the above-described composition onto the skin and detaching the porous composite powder from the skin using a magnetic applicator.

The magnetic applicator may have a spoon-like shape with a short tip, but is not limited to this. In addition, a neodymium magnet may be used so that the surface of the bottom of the head portion can exhibit a magnetic field of 2000 to 4000 G, but is not limited to this.

A method for manufacturing a porous composite powder for removing fine dust In an exemplary embodiment of the present invention, a method for manufacturing the porous composite powder described above is provided, which includes the steps of: preparing a solution containing a polymer; dispersing magnetic particles in the solution containing the polymer; and spray-drying the solution in which the magnetic particles are dispersed.

Specifically, referring to FIG. 1, the polymer is dissolved in an organic solvent such as DCM to prepare a solution containing the polymer, and magnetic particles are added to the solution, which can then be dispersed using a homogenizer. The solution in which the magnetic particles are dispersed can then be spray-dried through a nozzle to produce a porous composite powder for removing fine dust.

In this way, using spray drying technology, it is possible to easily produce porous composite powder in which magnetic particles are uniformly impregnated inside a polymer in a single process.

At this time, the internal humidity of the spray dryer may be maintained at 30% or more, the internal temperature may be maintained at room temperature, and spray drying may be performed under the following conditions: feed rate: 20%, aspirator: 70%, 20 atm.

In one embodiment, during the spray drying, the solution in which the magnetic particles are dispersed may be stirred in a container before being pumped, thereby preventing the magnetic particles from settling before spray drying.

In one embodiment, the solvent of the solution containing the polymer may be one or more selected from the group consisting of dichloromethane anhydrous, ethanol, and acetone, and may be preferably dichloromethane.

In one embodiment, the method may further include a methanol washing and tray drying step after the spray drying step, thereby obtaining a porous composite powder from which the remaining solvent has been completely removed.

The present invention will now be described in more detail with reference to the following examples. Note that the following examples are provided merely for illustrative purposes to aid in understanding the present invention, and are not intended to limit the scope of the present invention.

Example - Preparation of porous composite powder for fine dust First, magnetic particles (iron oxide, manufactured by Daito Chemical Industry Co., Ltd.), lactic acid/glycolic acid copolymer (PLGA, manufactured by Galactic Corporation), and dichloromethane anhydrous (DCM, manufactured by Sigma-Aldrich, purity >99.8%) were prepared, and lactic acid/glycolic acid copolymer (PLGA) composite powder impregnated with magnetic particles (hereinafter referred to as AP spheres) was prepared as follows.

1) 40 g of PLGA was dissolved in 1 L of DCM solvent.
2) 40 g of magnetic particles were added to the PLGA solution and then dispersed using a homogenizer.
3) The PLGA solution in which the magnetic particles were dispersed was spray-dried using a spray dryer manufactured by the applicant (see FIG. 1).
4) The internal humidity of the spray dryer was maintained at 30% or higher, and the internal temperature was maintained at room temperature.
5) The mixture was spray-dried under the following conditions: Feed rate: 20%, Aspirator: 70%, and 20 atm. The PLGA solution in which the magnetic particles were dispersed was continuously stirred with a stirrer during spray-drying.
6) The spray-dried magnetic particle/PLGA composite powder was thoroughly washed and then dried to completely remove the remaining solvent, and then collected.

<Surface observation of porous composite powder>
2a and 2b, it was confirmed that pores with a diameter of several hundred nanometers were formed and that iron oxide particles were densely impregnated from the surface photographs.In addition, in the case of a sample of iron oxide:PLGA=80:20, the actual loss on ignition was measured by treating 1g at 500°C for 180 minutes to burn off all the polymer and then measuring the weight loss, and the result was 19-21%, which confirmed that iron oxide was uniformly impregnated inside the composite powder.

<Confirmation of the pore structure of the porous composite powder>
As a result of examining the pore structure of the AP sphere, referring to Figures 10a and 10b, the total intrusion volume was 0.62 mL/g, which was confirmed to be similar to the oil absorption (0.48 mL/g) measured using an oil absorption measurement device (S-500, manufactured by Asahi Souken, Figures 3a and 3b) described below. In addition, the average pore diameter (4V/A) was 0.33 μm, which was similar to the pore diameter on the SEM image (Figures 2a and 2b).

In addition, the porosity, which means the total percentage of pores that can actually absorb sebum, is at a level of 61% in the example, which is an effect achieved by maintaining the internal pore structure despite being impregnated with 80% iron oxide particles.

Experimental Example - Oil Absorption Test In order to confirm whether the AP ball can effectively absorb sebum containing fine dust into the pores, the oil absorption test was performed on MCT oil (CAS. No. 73398-61-5) which has the most similar physical properties to sebum, using an oil absorption tester (S-500, manufactured by Asahi Souken, Figures 3a and 3b) in the following manner, and the results are shown in Figure 4.

1) The powder to be measured was weighed and then placed in a sample chamber.
2) When the oil absorption measuring equipment started to operate, the oil pump dropped oil drop by drop into the chamber, where two mixers rotated to mix the powder and oil.
3) As the amount of oil added increased, the torque applied to the mixer also increased, and the test was completed when it reached a maximum value.
4) The amount of oil (ml) corresponding to 70% of the maximum torque was divided by the amount of sample to calculate the oil absorption (ml/g) of the powder. Specifically, the amount of oil was 14.09 ml, the amount of sample was 29.35 g, and the oil absorption value was calculated as 14.09/29.35=0.48 ml/g.

Referring to Figure 4, the oil absorption of iron oxide itself is 0.28 ml/g, but in the case of AP spheres with iron oxide impregnated inside PLGA, the oil absorption is 0.48 ml/g, which is almost double. This is because, even though the AP spheres contain 80% iron oxide, numerous pores are formed on the surface and inside of the composite powder, maintaining porosity. Therefore, it can be said that the use of AP spheres is more effective at absorbing fine dust contained in sebum than the use of iron oxide alone, and is more effective at isolating harmful fine dust from the skin by capturing it inside the pores.

Experimental Example - Heavy Metal Inhalation Simulation To confirm whether fine dust is actually inhaled inside the AP sphere, a standard solution of the five major heavy metals (Cd, Hg, Sb, Pb, As each at 200 ppm) was fully absorbed into the AP sphere for one hour, and then it was dried and qualitatively analyzed by SEM-EDX Mapping (electron microscope elemental analysis) with different hues for each element, the results of which are shown in Figure 5. As a result of the experiment, it was confirmed that the five major heavy metal elements are actually distributed uniformly inside the AP sphere particles.

Experimental Example - Evaluation of Fine Dust Removal Performance A metal mold capable of manufacturing a pore mimic having multiple artificial pores with a diameter of 50 μm and multiple artificial pores with a diameter of 200 μm was fabricated, and then the mold was coated with polydimethylsiloxane (PDMS; SYLGARD® 184 (Sigma, USA) was used as a raw material), and when the PDMS was completely cured, it was removed from the mold to obtain a pore mimic. Carbon black nanoparticles of 500 nm or less were used as the fine dust mimic material, and the fine dust removal performance of the AP sphere was evaluated as follows, and the results are shown in Figure 6.

1) A fine dust solution was prepared by mixing MCT (Medium Chain Triglyceride oil), BG (Butylene Glycol) and carbon black in a specific ratio (MCT oil: BG: carbon black = 77.9: 20.8: 1.3).
2) Separately from the fine dust solution prepared in 1), AP spheres (PLGA + iron oxide) and MCT oil were mixed in a ratio of 50:50 to prepare a composition containing porous composite powder for removing fine dust.
3) After the fine dust solution was applied to the surface of the pore mimic, a composition containing a fine dust removing porous composite powder was applied thereon.
4) The surface of the pore mimic was rubbed 30 times each with a tissue and a magnet (1000 Gauss) wrapped in the tissue, and then the surface was observed under a microscope.

Referring to Figures 6a and 6b, it was observed that when the carbon black was removed using only tissue, almost none of the carbon black inside the pores was removed, whereas when the carbon black was removed using a magnet wrapped in tissue, most of the carbon black inside the pores was removed. This confirmed that the AP spheres, which are porous particles that have been given magnetism, can absorb the carbon black inside the pore mimics, and when magnetic force is applied from the outside, they can be easily detached from the pores.

Experimental Example - Magnetic Strength Measurement The AP spheres manufactured in the examples were impregnated with iron oxide at 50%, 80% and 100% by weight (100% was an iron oxide sample for simply comparing magnetic properties), and the magnetic strength was measured. Referring to Figure 9, it was confirmed that the magnetic strength is directly proportional to the proportion of magnetic particles (iron oxide), and that when 80% by weight of iron oxide was impregnated as in the examples, the magnetic strength was reduced to about 80% compared to 100% iron oxide.

Claims (17)

A porous composite powder for removing fine dust, comprising:
The porous composite powder is
a polymer; and magnetic particles impregnated in the polymer;
The particle size of the porous composite powder is in the range of 20 to 100 μm;
The porous composite powder for removing fine dust is a biodegradable polymer . 2. The porous composite powder for removing fine dust according to claim 1, wherein the biodegradable polymer is one or more selected from the group consisting of polycaprolactone (PCL), polylactic acid (PLA), and lactic acid-glycolic acid copolymer (PLGA). The porous composite powder for removing fine dust according to claim 1 or 2, wherein the magnetic particles are one or more selected from the group consisting of _{Fe ,} Ni, Co, _MnFe2O4 , _BaO.6Fe2O3 , an alloy of Al, an alloy of Ti, an alloy of Cu, and iron oxide. The porous composite powder for removing fine dust according to any one of claims 1 to 3 , wherein the magnetic particles are Fe ₃ O ₄ . 5. The porous composite powder for removing fine dust according to claim 1 , wherein the impregnation ratio of the magnetic particles is in the range of 50 to 90% by weight based on the total weight of the porous composite powder. 6. The porous composite powder for removing fine dust according to claim 1, wherein the pore diameter of the porous composite powder is in the range of 100 nm to 10 μm. The porous composite powder for removing fine dust according to any one of claims 1 to 6 , wherein the porosity of the porous composite powder is in the range of 30 to 80%. 8. The porous composite powder for removing fine dust according to claim 1 , wherein the magnetic strength of the porous composite powder is in the range of 30 to 70 emu/g. The porous composite powder for removing fine dust according to any one of claims 1 to 8 , which is used to remove fine dust having a particle size of 2.5 µm or less. A composition for removing fine dust, comprising the porous composite powder according to any one of claims 1 to 9 . The composition for removing fine dust according to claim 10 , wherein the content of the porous composite powder is in the range of 30 to 70% by weight based on the total weight of the composition. 12. The composition for removing fine dust according to claim 10 or 11 , which is a cosmetic composition. A method for removing fine dust, comprising: applying the composition according to any one of claims 10 to 12 onto the skin; and detaching the porous composite powder from the skin using a magnetic applicator. A method for producing the porous composite powder according to any one of claims 1 to 9 , comprising the steps of:
Producing a solution comprising a polymer;
A method for producing a porous composite powder for removing fine dust, comprising: dispersing magnetic particles in a solution containing the polymer; and spray-drying the solution in which the magnetic particles are dispersed. The method for producing a porous composite powder for removing fine dust according to claim 14 , further comprising stirring the solution in which the magnetic particles are dispersed during the spray drying. 16. The method for producing a porous composite powder for removing fine dust according to claim 14 or 15 , wherein the solvent of the solution containing the polymer is at least one selected from the group consisting of dichloromethane anhydrous, ethanol, and acetone. The method for producing a porous composite powder for removing fine dust according to any one of claims 14 to 16 , further comprising the steps of washing and drying after the spray drying step.

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