KR20210021174A - Sterilizing filter - Google Patents

Abstract

The present invention relates to a sterilization filter and, more specifically, to a sterilization filter which comprises: a piezoelectric element capable of generating an output voltage of 100 mV or greater by a pressure change; a wind discharge means capable of changing the pressure of the piezoelectric element by discharging wind to one side of the piezoelectric element; a sterilization active layer bonded to the other side of the piezoelectric element, and having a sterilization function that is activated by an electric current generated by the piezoelectric element; and a filtering member capable of filtering out predetermined particles on the sterilization active layer. According to the present invention, the sterilization filter has a high rate of removing fungi, bacteria, or viruses in the air as its sterilization activity is increased by electric energy generated by the piezoelectric element.

Description

Sterilizing filter {Sterilizing filter}

The present invention relates to a sterilization filter, and more particularly, to a sterilization filter having a high removal rate of fungi, bacteria or viruses in the air by increasing sterilization activity by electric energy generated from a piezoelectric element.

Silver (silver) has been known to have an antibacterial effect from ancient times. In particular, silver colloid refers to a substance in a state dispersed in a cluster state (10nm to 150nm size) in an aqueous solution.

It has been found that these colloidal silver nanoparticles have strong antibacterial activity against about 650 kinds of harmful bacteria and fungi. Silver colloidal particles show sterilization against various bacteria, viruses, and allergic disease bacteria by stopping the enzyme action, destroying the cell wall, and inhibiting the metabolism of the bacteria because it is easy for bacteria and viruses to penetrate into the cells.

In addition, it has been observed that silver colloidal particles do not kill most of the beneficial bacteria when applied to the human body.

In the United States and other places, silver colloidal solution is recognized as a natural substance that is harmless to the human body registered in the FDA pharmaceutical scope, and recently, it is known as a non-toxic substance to the human body or living body enough to function as a food additive as a non-toxic preservative.

In addition, efforts have been made to provide antibacterial properties by applying silver nanoparticles to filters in order to remove foreign substances such as bacteria, mold, and dust contained in the air by being installed in devices such as air purifiers and blowers.

As described above, the silver colloidal solution has excellent antibacterial properties and is proven to be non-toxic to the human body.Therefore, in countries around the world, in addition to the production of silver particles more effective for antibacterial and eradication of pathogenic bacteria and development of therapeutic agents using the same, cosmetics, textiles, wallpaper, washing machines Research on the use of silver in various products such as clothing, air purifiers, etc. is ongoing.

In this regard, U.S. Patent Publication No. 2006-0020108 discloses a method for preparing a polyester master batch by mixing and polymerizing a glycol containing a silver precursor with terephthalic acid. However, in the above patent, there is a problem that only a portion of silver is reduced from the silver precursor, so that antimicrobial properties due to silver particles may be reduced.

In addition, Korean Patent Publication No. 2017-0040919 discloses an antibacterial deodorant composition for tents using a coating solution containing silver nano sols containing silver particles in a concentration of 500 to 2000 ppm. In the above patent, silver nanoparticles of a high concentration are used to maintain antimicrobial expression and persistence, but there is a problem in that the silver nanoparticles may aggregate and aggregate, and as shown in Non-Patent Document 1, harmfulness to the human body may occur.

In addition, Korean Patent No. 695264 proposes an antibacterial filter manufactured by mixing silver colloid and titanium dioxide, which are antimicrobial particles, in a volatile solution, and then applying it on the filter by spraying and drying it. However, as the liquid component is volatilized and only the antibacterial particles are applied on the filter, the antibacterial particles are easily separated from the filter due to external vibration, and the antibacterial activity is lowered.

US Patent Publication No. 2006-0020108 Korean Patent Publication No. 2017-0040919 Korean Patent No. 695264

Sujin Kim and 15 others, Research on the harmfulness of manufactured silver nanomaterials, National Institute of Environmental Sciences, NIER No. 2010-49-1224

As a result of trying to solve the above problems, an object of the present invention is to provide a sterilizing filter capable of exhibiting excellent antibacterial activity by using silver nanoparticles having a low content so as to be harmless to the human body.

In addition, an object of the present invention is to provide a sterilization filter capable of removing fungi, bacteria, or viruses in the air by activating a sterilization function by a piezoelectric element.

In addition, an object of the present invention is to provide a sterilizing filter capable of exhibiting excellent antibacterial activity without applying silver nanoparticles on the filter.

The present invention is a piezoelectric element capable of generating an output voltage of 100 mV or more by a pressure change; A wind-releasing means capable of changing the pressure of the piezoelectric element by emitting wind to one side of the piezoelectric element; A sterilizing active layer bonded to the other side of the piezoelectric element to activate a sterilizing function by an electric current generated from the piezoelectric element; And a filtering member capable of filtering predetermined particles on the sterilizing active layer.

A polymer cover layer may be additionally formed between the piezoelectric element and the sterilizing active layer.

The polymer cover layer may be made of a conductive polymer.

The conductive polymer is polyethylene terephthalide (PET), polyethylene naphthalate (PEN), polyimide (PI), polyethersulfone (PES), polyacrylate (PAR), polyether imide (PEI), polyphenylene sulfide. (PPS), polyallylate, polycarbonate (PC), cycloolefin polymer (COP), cycloolefin copolymer (COC), cellulose triacetate (CTA), cellulose acetate propionate (CAP), nobor It may be one or more selected from the group consisting of nen-based resins and combinations thereof.

The cycloolefin polymer may be a heterocyclic compound.

The heterocyclic compound may be polypyrrole.

The piezoelectric element may generate an output voltage of 100 to 400 mV.

The piezoelectric element is one selected from the group consisting of quartz, Rachelle salt, barium titanate (BaTiO ₃ ), ammonium dihydrogen phosphate crystal, ethylenediamine tatarate crystal, PZT and polyvinylidene fluoride (PVDF) It can be made of the above materials.

The predetermined particles may have a size of 2.5 to 10 μm.

The filtering member may be made of at least one material selected from the group consisting of polynylon, polyamide, polyphenylene sulfide (PPS), polyester, polypropylene (PP), and polyterafluoroethylene (PTFE).

The bactericidal active layer may contain 0.01 to 0.1% of nanoparticles of silver (Ag), copper, or a mixed metal thereof.

The bactericidal active layer may be a coating layer or a film layer.

The sterilizing filter may remove 74 to 95% of bacteria.

The sterilization filter according to the present invention has the advantage that the sterilization layer including silver nanoparticles is activated by the electric energy generated through the piezoelectric element, so that the removal efficiency of fungi, bacteria or viruses is excellent.

In addition, the sterilizing filter according to the present invention has the advantage of exhibiting excellent antibacterial activity by using a low content of silver nanoparticles.

In addition, the sterilization filter according to the present invention has the advantage of minimizing harmfulness to the human body by using silver nanoparticles of a low content.

In addition, the sterilizing filter according to the present invention has the advantage of improving the air cleaning ability of hospitals, pharmaceutical companies, food companies, and multi-use facilities by filtering fine dust as well as antibacterial effects.

1 to 3 each show a sterilizing filter according to an example of the present invention.
4 shows a process of generating a voltage in a piezoelectric device applied to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. DETAILED DESCRIPTION OF THE INVENTION The detailed description to be disclosed hereinafter together with the accompanying drawings is intended to describe exemplary embodiments of the present invention, and is not intended to represent the only embodiments in which the present invention may be practiced. The following detailed description includes specific details to provide a thorough understanding of the present invention. However, those of ordinary skill in the art to which the present invention pertains knows that the present invention may be practiced without these specific details.

In some cases, in order to avoid obscuring the concept of the present invention, well-known structures and devices may be omitted, or may be shown in a block diagram form centering on core functions of each structure and device.

Throughout the specification, when a part is said to "comprising or including" a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary. do. In addition, the term "... unit" described in the specification means a unit that processes at least one function or operation.

In addition, "a or an", "one", "the" and similar related words are different from the present specification in the context of describing the present invention (especially in the context of the following claims). Unless otherwise indicated or clearly contradicted by context, it may be used in a sense encompassing both the singular and the plural.

In describing the embodiments of the present invention, if it is determined that a detailed description of a known function or configuration may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted. In addition, terms to be described later are terms defined in consideration of functions in an embodiment of the present invention, which may vary according to the intention or custom of users or operators. Therefore, the definition should be made based on the contents throughout this specification.

Referring to the accompanying drawings, preferred embodiments of the present invention will be described in detail with respect to the sterilization device as follows.

1 to 3 each show a sterilizing filter according to an example of the present invention.

1 is a piezoelectric element 100, a wind-releasing means 200 formed under the piezoelectric element 100, a sterilizing active layer 300 formed on the piezoelectric element 100, and on the sterilizing active layer 300 It is a sterilizing filter having a structure in which the filtering member 400 is formed.

In general, when the piezoelectric element 100 exerts a physical force pressure from the outside, the piezoelectric element is twisted or deformed by impact due to the pressure transmitted to the piezoelectric element 100, resulting in a voltage of 100 to 400 mV. Occurs. This principle is a phenomenon in which electrical polarization occurs on the surface of a crystal when a force is applied to a solid, and is referred to as a piezo effect, and a process in which electrical energy is generated in the piezoelectric element 100 will be described as follows.

As shown in FIG. 4, when a force (F) is applied to the piezoelectric element 100 from the outside, stress is generated in the inner direction of the piezoelectric element 100 and the piezoelectric element 100 is compressed (t ₀ >t ₁ ). Positive and negative charges are accumulated in electrode A, which is an anode metal plate, and electrode B, which is a cathode metal plate, respectively. If positive ions are generated from electrode A and negative ions are generated from electrode B, and the internal pressure (P) of the piezoelectric element is high and stress is generated in the external direction of the piezoelectric element, the piezoelectric element is elongated (t ₀ <t ₂ ), and the electrode A and Positive and negative charges are accumulated on the electrode B, respectively, and an anion is generated from the electrode A and a cation is generated from the electrode B.

According to the principle as described above, the piezoelectric element 100 is polarized by air introduced from the wind-releasing means 200 formed at one side to generate an output voltage of 100 mV or more, preferably 100 to 400 mV. It is good to generate the output voltage of.

When the piezoelectric element 100 generates an output voltage of less than 100 mV, the sterilization effect may be lowered due to a low voltage, and when it exceeds 400 mV, the voltage may increase and cause a harmful effect on the human body.

The piezoelectric device 100 is not particularly limited as long as it is commonly used in the art, but crystal, Rachelle salt, barium titanate (BaTiO ₃ ), ammonium dihydrogen phosphate crystal, ethylenediamine tartrate crystal, PZT And polyvinylidene fluoride (PVDF) may be made of at least one material selected from the group consisting of.

Preferably, the piezoelectric element 100 is a flexible polymeric piezoelectric material, and is preferably made of polyvinylidene fluoride (PVDF), which is easily deformed according to the shape of the contacted portion when used. For example, it may be manufactured in a form in which a ventilation hole is formed so that air introduced from the wind emission means 200 can pass, and a plurality of thermoelectric elements 100 are inserted into a flexible support (not shown).

The wind discharging means 200 for changing the pressure of the piezoelectric element 100 may be a blower capable of generating a flow of internal air by sucking outside air. Specifically, the blower may include a fan and a motor, and as the fan rotates, the pressure may be changed by releasing wind to the piezoelectric element.

In addition, the wind discharging means 200 may adjust the driving speed of the fan by a controller (not shown), and accordingly, the amount of electric energy generated by the piezoelectric element 100 may be adjusted.

On the other side of the piezoelectric element 100, a sterilization active layer 300 is formed in which a sterilization function is activated by electric energy generated from the piezoelectric element 100.

The bactericidal active layer 300 may be formed as a coating layer or a film layer, and may include nanoparticles of silver, copper, or a mixed metal thereof.

At this time, the sterilizing active layer 300 may include 0.01 to 0.1% of silver (Ag), copper, or a mixed metal nanoparticle thereof.

If the metal nanoparticles are included in less than 0.01%, the sterilizing power may be reduced, and if the metal nanoparticles are included in more than 0.1%, the particles may aggregate, resulting in a non-uniform thickness and reduced processability, which is inefficient in terms of economy.

As such, by forming the sterilizing active layer 300 on the other side of the piezoelectric element 100, the silver or copper nanoparticles are activated by the electric energy generated from the piezoelectric element 100 and are released as silver or copper ions, and fungi in the air. , Can remove viruses or bacteria.

The sterilizing active layer 300 is piezoelectric using a coating solution containing silver or copper nanoparticles and a solvent by reverse coating, gravure coating, spin coating, screen coating, fountain coating, dip coating, bar coating, and spraying. It can be manufactured by applying it on the device 100 and then drying it.

In addition, the bactericidal active layer 300 is not only antifungal, antibacterial, antiviral, etc., in order to maintain a thin and even coating properties, iron oxide (Fe ₂ O ₃ , Fe ₃ O ₄ ), manganese dioxide (MnO ₂ ), and At least one particle selected from the group consisting of hepatitis, copper oxide (CuO), copper nitrate (Cu(NO ₃ ) ₂ ·3H ₂ O), sodium borate 10 hydrate (Na ₂ B ₄ O ₇ ·10H _{2 O) and ceramics} May additionally be contained.

When the bactericidal active layer 300 is formed as a film layer, it may be prepared by applying a coating solution containing silver or copper nanoparticles and a solvent on the breathable polymer film.

The breathable polymer film may be prepared by extruding and stretching an inorganic material such as calcium carbonate with a polyolefin, but is not limited thereto, and a commercial polyolefin breathable film known in the art may be purchased and used. In addition, the coating solution may further include a dispersant to minimize aggregation between silver or copper nanoparticles to form nanoparticles having a uniform particle size.

The polymer film may be manufactured by bonding on a piezoelectric element, and bonding methods are bonded by methods such as bonding, ultrasonic bonding, high-frequency bonding, and thermal bonding generally used in the art. As an example, it may be bonded using a pressure-sensitive adhesive composition including a pressure-sensitive adhesive resin. The pressure-sensitive adhesive resin is, for example, acrylic copolymer, natural rubber, styrene-isoprene-styrene (SIS) block copolymer, styrene-butadiene-styrene (SBS) block copolymer, styrene-ethylenebutylene-styrene (SEBS) block copolymer. Conventional polymers such as coalescence, styrene-butadiene rubber, polybutadiene, polyisoprene, polyisobutyrene, butyl rubber, chloroprene rubber and silicone rubber can be used, and it is preferable to use an acrylic copolymer with easy control of adhesion. Do.

A filtering member 400 capable of filtering predetermined particles is formed on the sterilizing active layer 300.

The filtering member 400 filters particles having a size of 2.5 to 10 μm present in air from which fungi, viruses, and bacteria are removed by the sterilizing active layer 300.

At this time, the filtering member 400 may be a pleated filter or a mesh filter to filter particles having a size of 2.5 to 10 μm. Preferably, a mesh filter having a size of 70 or more mesh holes capable of passing air and removing dust and foreign substances in the air is preferable. Here, the meaning of '70 necks' means that the number of nets formed in an area of 1 cm in width and height of the mesh filter is 70.

The filtering member 400 may be made of one or more materials selected from the group consisting of polynylon, polyamide, polyphenylene sulfide (PPS), polyester, polypropylene (PP), and polyterafluoroethylene (PTFE). And, considering the harm to the human body, pressure loss, etc., it is preferable that it is made of polyester.

In addition, the filtering member 400 may be integrally formed on the sterilizing active layer 300 or may be detachably accommodated in a replaceable structure.

In this way, it is possible to filter fine dust as well as antibacterial effects against fungi, viruses, or bacteria, and thus, when used in an air purification device, air cleaning capacity of hospitals, pharmaceutical companies, food companies, and multi-use facilities can be improved.

FIG. 2 shows another embodiment of the present invention, and as shown in FIG. 2, a polymer cover layer 500 is additionally formed between the piezoelectric element 100 and the bactericidal active layer 300.

Specifically, the sterilization device of FIG. 2 is a case in which a polymer cover layer 500 is formed on the other side of the piezoelectric element 100, and as described in FIG. 1, by the electric energy generated from the piezoelectric element 100 The sterilizing active layer 300 is activated and silver or copper ions are released to have sterilizing power.

At this time, by additionally including a polymer cover layer 500 on the other side of the piezoelectric element 100, since the electrical conductivity from the piezoelectric element 100 to the sterilizing active layer 300 is improved, the silver contained in the sterilizing active layer 300 Alternatively, the sterilization effect can be increased even when the content of the copper nanometal is small.

The polymer cover layer 500 may be made of a conductive polymer, and the material of the conductive polymer is not particularly limited as long as it does not inhibit the antifungal, antibacterial, and antiviral properties of the activated metal nanoparticles. Specifically, polyethylene terephthalide (PET), polyethylene naphthalate (PEN), polyimide (PI), polyethersulfone (PES), polyacrylate (PAR), polyetherimide (PEI), polyphenylene sulfide (PPS) ), polyallylate, polycarbonate (PC), cycloolefin polymer (COP), cycloolefin copolymer (COC), cellulose triacetate (CTA), cellulose acetate propionate (CAP), norbornene resin And one or more selected from the group consisting of a combination thereof may be used.

The conductive polymer is preferably a cycloolefin polymer in consideration of conductivity, price competitiveness, and ease of handling, and the cycloolefin polymer is more preferably a heterocyclic compound, and the heterocyclic compound is more preferably polypyrrole.

3 shows another embodiment of the present invention, as shown in FIG. 3, consisting of polypyrrole, which is a heterocyclic compound, as a polymer cover layer 500 between the piezoelectric element 100 and the bactericidal active layer 300. The polypyrrole layer 600 may be formed. The polymer cover layer 500 of FIG. 2 or the polypyrrole layer 600 of FIG. 3 may be manufactured in the form of a film having pores so that air supplied from the wind-releasing means 200 can pass.

In this way, the polymer cover layer 500 of FIG. 2 or the polypyrrole layer 600 of FIG. 3 bonded to one surface of the piezoelectric element 100 has a bactericidal active layer 300 formed on the other surface. The electrical conductivity is increased by the polymer cover layer 500 of FIG. 2 or the polypyrrole layer 600 of FIG. 3 to improve the sterilizing power of the sterilizing active layer 300. In addition, by minimizing the content of silver nanoparticles, it is harmless to the human body and has excellent antibacterial activity.

In addition, the thermoelectric element 100 of FIG. 3 and the polypyrrole layer 600 bonded to one surface thereof may have a sterilizing activity like the sterilizing filter shown in FIG. 1.

As described above, in the sterilizing filter according to FIGS. 1 to 3 of the present invention, the sterilizing active layer 300 is activated by the wind discharging means 200 and the piezoelectric element 100 generating electric energy by the wind discharging means 200 It has excellent removal efficiency of fungi, bacteria, and viruses. Specifically, the sterilizing filter of the present invention can remove 74 to 95% of bacteria.

In addition, the sterilization filter according to FIGS. 1 to 3 of the present invention has excellent removal efficiency of fine particles such as dust, and specifically, can remove 90% or more of particles having a size of 2.5 to 10 μm.

Hereinafter, preferred embodiments are presented to aid in the understanding of the present invention, but the following examples are only illustrative of the present invention, and it is obvious to those skilled in the art that various changes and modifications are possible within the scope and spirit of the present invention. , It is natural that such modifications and modifications fall within the appended claims.

silver( Ag ) Containing active layer

< Manufacturing example 1. Coating liquid manufacturing>

By pulverizing 5 g of pure silver (Ag) having a silver content of 99.9% or higher purity into a nano size (Nano Size, 5 to 10 nm) to form fine particles, and dissolving the prepared silver fine particles in 1 L of ammonia water and then acid treatment. A silver colloid solution was prepared. At this time, the silver colloidal solution was prepared to contain 0.05% silver nanoparticles.

< Manufacturing example 2. Film Manufacturing>

50% of calcium carbonate (Samjin Polytech) was mixed with a commercially available polyolefin resin (LLDPE ST408 30%, LDPE BB150 20%). Then, T-die extrusion was performed in a film extruder at 230° C., 10 rpm, and 25 bar to obtain a breathable film. The coating solution of Preparation Example 1 was coated on the surface of the breathable film to a thickness of 300 Å through a dip coating method, and dried at 90° C. for 1 hour to prepare a film containing silver nanoparticles.

Bactericidal active layer containing copper

< Manufacturing example 3. Coating liquid manufacturing>

After measuring 38.01 g of copper nitrate (Cu(NO ₃ ) ₂ ·H ₂ O (Tongyang Steel Chemical Co.)) and transferring it to a 1L beaker, distilled water was added and slowly stirred to completely dissolve the copper nitrate. To do this, measure at least 1 mol of hydrazine hydrate (N ₂ H ₂ H ₂ O) as a reducing agent in 1 mol of copper nitrate in another container, and add the reducing agent dropwise while stirring the solution in which the copper nitrate is dissolved at a speed of 1,000 rpm. To remove excess hydrazine hydrate and by-products, filtration and washing were performed 5 times and then completely dried to obtain 10 g of copper powder having an average size of 0.1 nm. 50 ml of distilled water was supplied to the solution, 0.5 g of polyvinyl alcohol was added and dissolved to prepare a solution containing copper.

At this time, the copper nano solution was prepared to contain 0.05% copper nanoparticles.

< Manufacturing example 4. Film manufacturing>

It was carried out in the same manner as in Preparation Example 2, but a film containing copper nanoparticles was prepared using the coating solution of Preparation Example 3.

Manufacture of sterilization filter

< Example 1>

A coating solution containing 0.05% of silver (Ag) nanoparticles prepared in Preparation Example 1 was prepared on one side of a piezoelectric element (Sensonic) made of polyvinylidene fluoride (PVDF). A sterilizing active layer was formed by coating evenly using 20. The piezoelectric element having the sterilizing active layer formed thereon was dried at 100° C. for 10 minutes, and a mesh-type filter (70 items) made of polyester was used as a filter member on the sterilizing active layer. Then, a blower (LG Innotek, TB-150) was mounted on the other side of the piezoelectric element, and then an air volume of 15 CFM was applied to measure the output voltage, antibacterial activity, and fine particle removal efficiency.

< Example 2>

In the same manner as in Example 1, a sterilizing filter was manufactured by additionally forming a polymer cover layer made of polyetherimide (PEI) between the piezoelectric element and the sterilizing active layer. At this time, the polymer cover layer was coated on one surface of the piezoelectric element to a thickness of 10 nm and then put into a drying furnace at 80° C. and dried for 10 minutes.

< Example 3>

In the same manner as in Example 1, a sterilizing device was manufactured by additionally forming a polymer cover layer made of polypyrrole between the piezoelectric element and the sterilizing active layer. At this time, the polypyrrole layer was coated on one surface of the piezoelectric element to a thickness of 10 nm, then put in a drying furnace at 80° C. and dried for 10 minutes.

< Example 4>

In the same manner as in Example 1, a sterilization filter was prepared using a solution containing 0.05% of the copper nanoparticles prepared in Preparation Example 3.

< Example 5>

In the same manner as in Example 2, a sterilization filter was prepared using a solution containing 0.05% of the copper nanoparticles prepared in Preparation Example 3.

< Example 6>

In the same manner as in Example 3, a sterilization filter was prepared using a solution containing 0.05% of the copper nanoparticles prepared in Preparation Example 3.

< Example 7>

It was carried out in the same manner as in Example 1, but instead of Preparation Example 1, a sterilization device was manufactured using Preparation Example 2 (a film containing 0.05% silver nanoparticles). The film prepared in Preparation Example 2 was bonded to a piezoelectric element using an adhesive made of an acrylic copolymer (AKITACK product, AK Chemtech Co., Ltd.).

< Example 8>

A sterilization filter was prepared in the same manner as in Example 1, but using Preparation Example 4 (film containing 0.05% copper nanoparticles) instead of Preparation Example 3. The film prepared in Preparation Example 4 was bonded to a piezoelectric element using an adhesive made of an acrylic copolymer (AKITACK product, AK Chemtech Co., Ltd.).

< Example 9>

It was carried out in the same manner as in Example 1, but a wind of 10 CFM was applied to the piezoelectric element.

< Example 10>

It was carried out in the same manner as in Example 1, but 50 CFM of wind was applied to the piezoelectric element.

< Comparative example 1>

A sterilizing filter was manufactured in the same manner as in Example 1, but using Preparation Example 2 (a film containing 0.05% silver nanoparticles) without a piezoelectric element.

< Comparative example 2>

It was carried out in the same manner as in Example 2, but a sterilizing filter was manufactured without a piezoelectric element.

< Comparative example 3>

A sterilizing filter was prepared in the same manner as in Example 1, but using a coating solution containing 0.008% silver (Ag) nanoparticles.

< Comparative example 4>

In the same manner as in Example 1, a sterilizing filter was prepared using a coating solution containing 1% silver (Ag) nanoparticles.

< Experimental example >

The output voltage, antibacterial performance, and fine particle removal efficiency were evaluated using the sterilizing filters according to the above Examples and Comparative Examples.

1. Output voltage measurement

The electrode of the piezoelectric element provided in the sterilizing filter of the present invention was connected to an oscilloscope (Tektronix, TDS 340A) through the evaluation wiring, and the output voltage was measured, and the results are shown in Table 1.

division Output voltage(mV) Example 1 250 Example 2 278 Example 3 265 Example 4 290 Example 5 353 Example 6 325 Example 7 279 Example 8 357 Example 9 85 Example 10 590 Comparative Example 1 2 Comparative Example 2 3 Comparative Example 3 245 Comparative Example 4 252

2. Antibacterial evaluation

For the microbial test for the evaluation of antimicrobial activity, only suitable microbes for the purpose of the experiment were purely cultured by preparing a suitable medium. In addition, reagents, glassware, etc. were all autoclaved at 121°C for 15 minutes or sterilized by filtration using a filter (pore size 0.2 to 0.45 μm).

As an indicator microorganism for evaluation of antimicrobial activity, antibacterial activity was tested against Escherichia Coli (ATCC 15597). The strain was cultured in a shaking incubator at 37° C. at a speed of 150 to 200 rpm, and then 0.3 ml was spread on a petri dish (150 mm) containing a solid medium (trypticase soy agar, 29 ml), and 37 Incubated for 12 to 18 hours (overnight) at ℃.

Into the Petri dish inoculated with the strain, a sample having a size of 10×10×1 mm, which is a filter according to the present invention, was put, incubated at 25°C for 50 minutes, and then colonies were counted according to Equation 1 below, and the equation According to 2, antimicrobial activity (%) was evaluated. The results are shown in Table 2.

[Equation 1]

N: colony forming unit per milliliter (CFU/ml)

CFU: Total number of colonies in Petri dish

α: Bacteria injection amount (ml)

d _i : dilution factor

[Equation 2]

(%) IE: Deactivation efficiency

N _treated : Colony forming unit per milliliter of sample with piezoelectric element

N _control : control (sample not equipped with piezoelectric element)

division Count after 50 minutes
(CFU/ml) Control Compared to the control group
Bacteria reduction rate (%) Example 1 2.17 Comparative Example 1 74 Example 2 1.16 Comparative Example 1 86 Example 3 0.42 Comparative Example 1 95 Example 4 5.01 Comparative Example 2 80 Example 5 3.80 Comparative Example 2 85 Example 6 2.39 Comparative Example 2 90 Example 7 1.75 Comparative Example 1 79 Example 8 4.03 Comparative Example 2 84 Example 9 7.33 Comparative Example 1 12 Example 10 2.49 Comparative Example 1 70 Comparative Example 1 8.32 Comparative Example 1 0 Comparative Example 2 25.2 Comparative Example 2 0 Comparative Example 3 7.48 Comparative Example 1 10 Comparative Example 4 6.24 Comparative Example 1 25

As shown in Tables 1 and 2, in Examples 1 to 3, it can be seen that the bacteria removal rate is 70% or more by a piezoelectric element generating an output voltage of 200 mV or more compared to Comparative Example 1. It can be seen that the sterilization device including the polymer cover layer made of polypyrrole removed 95% of bacteria.

On the other hand, the output voltages generated in Comparative Examples 3 and 4 were similar to those of Examples 1 to 3, but the antibacterial activity was hardly measured due to the low silver content.

In addition, it can be seen that the sterilization apparatus using the sterilizing active layer containing copper nanoparticles through Examples 4 to 6 exhibited a bacteria removal rate of 90% compared to Comparative Example 2.

In addition, through Examples 7 and 8, it was found that the antimicrobial activity was equal to or further increased as in Examples 1 to 6 in a sterilizing device formed by bonding a sterilizing active layer containing silver or copper nanoparticles to a piezoelectric element in a film form.

As a result of measuring the antibacterial activity according to the magnitude of the force applied to the piezoelectric element, as can be seen through Examples 9 and 10, when wind was applied to the piezoelectric element at a flow rate of 10 CFM, the output voltage was low, so that the antibacterial effect hardly appeared. . In addition, when wind is applied to the piezoelectric element at a flow rate of 30 CFM, the output voltage is high, but there is little difference in the antibacterial effect.

3. Fine dust removal efficiency

According to the German combination cycle test method DIN71460 standard, the performance evaluation for the removal efficiency by particle size was conducted, and the results are shown in Table 2. As an evaluation condition, the concentration of fine dust was maintained at ^{20 mg/m 3.}

division Removal efficiency by particle size (%) Particle size (㎛) 1.0~3.0 3.0~5.0 5.0~10.0 Example 1 91 94 96.9 Example 2 92.4 95.5 97 Example 3 94.5 97.4 99.5 Example 4 92 93.1 96.1 Example 5 92.5 94.2 97.5 Example 6 92 94 97 Example 7 92 95 97 Example 8 92 93.5 95.5 Example 9 85.1 88.7 92 Example 10 80.6 84.2 90.9 Comparative Example 1 88 89.1 90.1 Comparative Example 2 87 89 90 Comparative Example 3 88.2 89.3 91.2 Comparative Example 4 89.9 90.0 91

In addition, as shown in Table 3, it was confirmed that the sterilizing filters of Examples 1 to 10 exhibited about 90% or more filtering efficiency at particle sizes of 1.0 to 3.0 μm, 3.0 to 5.0 μm, and 5.0 to 10.0 μm. Based on the above test results, it was confirmed that the sterilizing filter according to the present invention has excellent properties for filtering fine dust.

The above description of the present invention is for illustrative purposes only, and those of ordinary skill in the art to which the present invention pertains will be able to understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not limiting. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as being distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the claims to be described later rather than the detailed description, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention. do.

100: piezoelectric element
200: wind emission means
300: sterilizing active layer
400: filter member
500: polymer cover layer
600: polypyrrole layer

Claims (13)

A piezoelectric element capable of generating an output voltage of 100 mV or more by a pressure change;
A wind-releasing means capable of changing the pressure of the piezoelectric element by emitting wind to one side of the piezoelectric element;
A sterilizing active layer bonded to the other side of the piezoelectric element to activate a sterilizing function by an electric current generated from the piezoelectric element; And
A sterilizing filter comprising a filter member capable of filtering predetermined particles on the sterilizing active layer.
The sterilizing filter according to claim 1, wherein a polymer cover layer is additionally formed between the piezoelectric element and the sterilizing active layer.
The sterilizing filter according to claim 2, wherein the polymer cover layer is made of a conductive polymer.
The method of claim 3, wherein the conductive polymer is polyethylene terephthalide (PET), polyethylene naphthalate (PEN), polyimide (PI), polyethersulfone (PES), polyacrylate (PAR), polyether imide (PEI). , Polyphenylene sulfide (PPS), polyallylate, polycarbonate (PC), cycloolefin polymer (COP), cycloolefin copolymer (COC), cellulose triacetate (CTA), cellulose acetate propionate ( CAP), a sterilizing filter, characterized in that at least one selected from the group consisting of norbornene-based resins and combinations thereof.
The sterilizing filter according to claim 4, wherein the cycloolefin polymer is a heterocyclic compound.
The sterilizing filter according to claim 5, wherein the heterocyclic compound is polypyrrole.
The sterilizing filter according to claim 1, wherein the piezoelectric element generates an output voltage of 100 to 400 mV.
The method according to claim 1, wherein the piezoelectric element is made of quartz, Rachelle salt, barium titanate (BaTiO ₃ ), ammonium dihydrogen phosphate crystal, ethylenediamine tartrate crystal, PZT and polyvinylidene fluoride (PVDF). A sterilizing filter, characterized in that made of at least one material selected from the group.
The sterilizing filter according to claim 1, wherein the predetermined particles have a size of 2.5 to 10 µm.
The method according to claim 1, wherein the filtering member is made of at least one material selected from the group consisting of polynylon, polyamide, polyphenylene sulfide (PPS), polyester, polypropylene (PP), and polyterafluoroethylene (PTFE). Sterilizing filter, characterized in that made.
The sterilizing filter according to claim 1, wherein the sterilizing active layer is a layer containing 0.01 to 0.1% of nanoparticles of silver, copper or a mixed metal thereof.
The sterilizing filter according to claim 1, wherein the sterilizing active layer is a coating layer or a film layer.
The sterilization filter according to claim 1, wherein the sterilization filter removes 74 to 95% of bacteria.

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