JP5067084B2 - Air purification filter and air purification device - Google Patents

Description

  The present invention relates to an air cleaning filter and an air cleaning device capable of removing particulate suspended matters and gaseous impurity components in the air, for example, in the field of air cleaning.

  Particulate suspended matter in the air, that is, dust, has been known as a cause of illnesses such as asthma and has been a target for removal in the past, but in recent studies, the particle size is 2.5 micrometers or less. There is a report that dust (so-called PM2.5) may induce diseases such as bronchitis, hay fever, and lung cancer, and further improvement of the collection technique is demanded. Among them, the dust collection filter made using filter media can surely collect the dust contained in the air, so it is necessary to collect the dust in the air and clean the air. Widely used in all cases.

  The filter medium forming the dust collecting filter includes a sheet-like material made of fibers, a porous membrane sheet-like material, a sponge-like material, etc., but here, as a representative, a filter material made of fibers having a thickness of 1 mm or less (hereinafter referred to as a filter material) The principle will be described using a dust collection filter made of a filter material sheet. The filter medium sheet is a sheet formed by spreading countless fibers, and a gap through which air can pass, that is, a so-called filter hole exists between the fibers. The fiber diameter of the fiber is several tens of μm at large, and about 0.2 μm at the small one. The smaller the fiber diameter, the easier the filtration holes become, and the smaller the fiber diameter when considering the same weight. As the total surface area of the fibers increases.

  Typical examples of filter media sheets that can collect small dust particles having a particle diameter of 1 μm or less include glass fiber filter media sheets and meltblown filter media sheets. The glass fiber filter sheet is a sheet in which fine glass fibers having a fiber diameter of 0.5 to several μm are mixed, and the glass fibers are bonded with a resin binder so as not to be loosened. The glass fiber filter sheet can obtain very high collection performance by taking advantage of the small fiber diameter of the glass fiber. Also, the melt-blown filter media sheet is made by blowing molten resin such as polypropylene with the power of high-temperature high-speed gas fluid to make the resin finer and fibrous, and spraying it on the screen in a half-melted state without using a binder Fibers are melt bonded to form a sheet. Resins such as polypropylene have the characteristics that they are easily polarized and that the generated polarization is difficult to escape.

  When dust is collected by the mechanical filtration action of the fiber, the dust is roughly collected on the fiber by three actions of inertial collision, interception and diffusion. Inertial collision refers to an action in which dust does not attach to the streamline of air that changes suddenly in the vicinity of the fiber and is collected by colliding with the fiber so as to cross the streamline of air as it is. Therefore, the larger the particle size and speed of the dust, the greater the inertial force acting on the dust and the greater the effect of inertial collision. Interception refers to the action of dust colliding with fibers and being collected on the fibers when they approach the fibers at a distance within the particle radius of the dust as the dust moves along the streamline of air. . Accordingly, the larger the particle diameter of the dust and the smaller the fiber diameter of the fiber, the greater the action of blocking. Diffusion refers to the action of causing the Brownian motion in which the dust moves in an irregular orbit due to air molecules moving in a thermal motion, and colliding with fibers on the orbit. Therefore, it operates only on dust having a particle size that is small enough to cause Brownian motion, and the total surface area of the fibers is larger, that is, the smaller the fiber diameter, the greater the diffusion effect. Calculations built up by theory and experiment reveal that inertial collisions and interruptions have a large effect on dust with a particle size of about 1 μm or more, and diffusion has a large effect on dust with a particle size of about 0.05 μm or less. Yes. Therefore, dust particles with a particle size of 1 μm or more or 0.05 μm or less are subject to inertial collision and blocking, and are easily collected due to diffusion. However, dust with particle size of 0.05 μm to 1 μm is subject to inertial collision and blocking. It has been clarified that the particle size is small for obtaining a large particle size, and that the particle size is large for obtaining a large diffusion effect, and thus it is difficult to be collected. In order to collect fine particles having a particle size of 0.05 μm or more and 1 μm or less, it is effective to increase the diffusion and blocking that act on the particles having a particle size in this range. By filling, dust having a particle diameter in this range can be collected well. As a high-performance dust collection filter mainly for clean rooms, according to Japanese Industrial Standards, it has a particle collection rate of 99.97% or more with respect to particles with a rated air volume of 0.3 μm and an initial pressure loss of 245 Pa. There is an HEPA filter defined as an “air filter having the following performance”, but the HEPA filter made of a filter medium sheet made of glass fiber has a very small fiber diameter of around 0.5 μm. Thus, dust collection performance can be enhanced by using fibers with a very small fiber diameter.

However, the smaller the fiber diameter of the fiber, the more tightly packed, the smaller the filter hole, and the greater the airflow resistance when passing air, that is, the pressure loss. Here, a constant electric field is provided as a dust collection filter using an electric field so that small dust can be well collected while reducing pressure loss using a filter medium sheet made of fibers having a relatively large fiber diameter. Patent Document 1 discloses a dust collection filter in which a force (van der Waals force) acting between fibers and dust is increased. The dust collection filter described in Patent Document 1 is shown in FIG. The dust collection filter described in Patent Document 1 includes an air layer 104 between at least one of a pair of conductive electrodes 102 and 103 provided on the upstream side and downstream side of the filter material sheet 101 and the filter material sheet. (In FIG. 10, an air layer 104 is provided on the upstream side), and if necessary, at least one electrode is covered with an insulating material and insulated to prevent short-circuiting between the pair of electrodes. It has become. A voltage is applied to the electrodes so as to give a potential difference of 6 to 9 kV between the pair of electrodes. In this way, a strong electric field is provided in the filter medium sheet 101, and the van der Waals force acting between the fibers of the filter medium sheet 101 and the dust is increased, so that dust with a particle size smaller than that of the filter hole is collected well. It is possible to do.
Japanese Patent No. 3388740

  In the dust collection filter described in Patent Document 1, a gap by an air layer is provided between at least one of the electrodes provided on the upstream side or the downstream side and the filter medium sheet in order to prevent short circuit, and the filter medium sheet There is a problem that dust collection performance is low because an electric field cannot be provided directly, and it is required to further improve dust collection performance.

  In addition, a relatively high voltage of 6 to 9 kV is necessary to improve the collection performance, and the surface of the insulating spacer provided for providing the air layer causes a dielectric breakdown to cause a short circuit, or the air layer causes a dielectric breakdown. Since a predetermined voltage cannot be obtained by causing a short circuit and an electric field cannot be provided on the filter medium sheet, a lower voltage is required.

  Moreover, although it is a different structure from patent document 1, when an air layer is not provided between a filter medium sheet and an electrode, it becomes possible to provide an electric field directly in a filter medium sheet. However, since the thickness of the filter medium sheet is generally very thin, 2 mm or less, if a voltage is applied so as to provide a potential difference between the upstream and downstream electrodes, the filter medium sheet is easily opened and a short circuit is likely to occur. Therefore, there is a demand for a structure that does not short-circuit even when a voltage is applied to the electrodes.

  In addition, when the filter medium sheet has a bellows pleated shape, the dimension of the filter medium sheet and the electrode in the pleat direction is several to several tens of times longer than the opening size of the dust collecting filter. It is very difficult and practically impossible to provide an air layer with a certain thickness between the pleated filter material sheet and the pleated filter material sheet. It is required to have a simple structure.

  In addition, substances that cause diseases such as fungi, mold spores, viruses, mite feces, dead bodies, and pollen are also present in the air as a kind of dust having a particle size of 0.1 to 50 μm. Therefore, an air purifying filter capable of detoxifying collected bacteria, molds, viruses and allergens is desired.

  It is also desired to collect gaseous impurity components that could not be collected by conventional dust collection filters. Furthermore, the collected gaseous impurity components are decomposed and rendered harmless for a long time. A dust collection filter capable of collecting impurity components and supplying clean air is desired.

  The present invention solves such a conventional problem, and it is possible to directly provide an electric field to the filter medium sheet by making both the upstream and downstream sides of the filter medium sheet semiconductive and applying a potential difference to both surfaces. Therefore, even if a relatively low voltage is used, high collection performance can be obtained. In addition, the collected bacteria, molds, viruses, and allergens are inactivated, and the gaseous state that cannot be collected by conventional dust collection filters. An object of the present invention is to provide an air cleaning filter and an air cleaning device capable of collecting and further detoxifying impurity components.

To achieve claim 1 air cleaning filter described above Symbol object of the present invention have a breathable, the both surfaces of the upstream and downstream of the filter medium sheet for collecting dust contained in the air passing through Harmful from dust and dust collected by the generated ozone, semi-conductive, double-sided semi-conductive filter media sheet, generating ozone by controlling the potential difference between both sides of the double-sided semi-conductive filter media sheet gas in which characterized that you purified into harmless gas ozone oxidation.

  Further, the air purification filter according to claim 2 is the air purification filter according to claim 1, wherein a semiconductive coating material that forms a semiconductive film is applied to both sides of the filter material sheet and dried to dry the filter. It is a sheet.

  The air purification filter according to claim 3 is the air purification filter according to claim 1, wherein a semiconductive ventilation sheet having air permeability and semiconductivity is provided on both sides of the filter medium sheet, and the double-sided semiconductive filter medium is provided. It is a sheet.

  According to a fourth aspect of the present invention, there is provided the air purification filter according to the second or third aspect, wherein a solution containing an ion conductive polymer is used as a semiconductive paint.

The air cleaning filter according to claim 5, wherein, in the air cleaning filter according to any one of claims 1 to 4, double-sided semi-conductive filter media sheet upstream and downstream face surface resistance are both 10 of the 8 It is characterized by being not less than the squared Ω / □ and not more than the 12th power Ω / □.

  The air purification filter according to claim 6 is the air purification filter according to any one of claims 1 to 5, wherein the filter material sheet is a glass fiber filter material sheet formed by combining glass fibers with a binder. It is a feature.

  Further, an air purification filter according to claim 7 is an air purification filter according to any one of claims 1 to 5, wherein a resin in which a filter medium sheet is melted is blown off with a high-speed gas fluid to form a fiber. It is a melt-blown filter material sheet formed into a sheet shape.

  The air purification filter according to claim 8 is the air purification filter according to any one of claims 1 to 7, wherein conductive terminals are provided on both surfaces of the double-sided semiconductive filter material sheet so as not to overlap projection. It is characterized by this.

  An air purification filter according to claim 9 is characterized in that, in the air purification filter according to any one of claims 1 to 8, the double-sided semiconductive filter material sheet is formed in a pleated shape.

  The air purification filter according to claim 10 is the air purification filter according to claim 9, wherein the two-dimensional network structure having conductivity is provided in contact with the apexes of the upstream and downstream pleat peaks, and the upstream side In addition, different voltages are applied to the two-dimensional network structure on the downstream side.

  The air purification filter according to claim 11 is the air purification filter according to claim 9, wherein the conductive rod-shaped member is provided in contact with the apexes of the upstream and downstream pleat peaks, and the upstream and downstream sides are provided. A different voltage is applied to each of the rod-shaped members.

  The air purification filter according to claim 12 is characterized in that, in the air purification filter according to any one of claims 1 to 11, the filter medium sheet or the double-sided semiconductive filter medium sheet has water repellency. .

  The air purification filter according to claim 13 is the air purification filter according to claim 12, wherein at least one of organopolysiloxane, fluororesin, and wax on the surface of the fiber of the filter medium sheet or the double-sided semiconductive filter medium sheet. A water-repellent film including one or more types is provided.

  The air purification filter according to claim 14 is the air purification filter according to claim 13, wherein a water repellent film containing organopolysiloxane is provided on the surface of the fiber of the filter medium sheet or the double-sided semiconductive filter medium sheet. The method is characterized in that an aqueous solution in which an organopolysiloxane and a polymer having a water-soluble group are dissolved is infiltrated into a filter medium sheet or a double-sided semiconductive filter medium sheet and then dried.

  The air purification filter according to claim 15 is the air purification filter according to claim 13 or 14, wherein a water repellent film containing a fluororesin is formed on the surface of the fiber of the filter medium sheet or the double-sided semiconductive filter medium sheet. As a method of providing, the filter medium sheet or the double-sided semiconductive filter medium sheet is infiltrated into an aqueous solution in which a polymer having a fluoroalkyl group and a water-soluble group is dissolved, and then dried.

  The air purification filter according to claim 16 is the air purification filter according to any one of claims 13 to 15, wherein the water repellent filter contains a wax on the surface of the fiber of the filter medium sheet or the double-sided semiconductive filter medium sheet. As a method for providing a membrane, the filter medium sheet or the double-sided semiconductive filter medium sheet is infiltrated into an emulsion prepared by mixing melted wax with an emulsifier and warm water, and then dried.

  The air purification filter according to claim 17 is characterized in that in the air purification filter according to any one of claims 1 to 16, a voltage including an alternating current component is applied between both surfaces of the double-sided semiconductive filter material sheet. Is.

  An air purifying filter according to claim 18 is characterized in that in the air purifying filter according to any one of claims 1 to 17, an adsorbent is supported on a double-sided semiconductive filter material sheet.

  The air purification filter according to claim 19 is the air purification filter according to any one of claims 10 to 18, wherein a honeycomb body carrying activated carbon is used as a conductive two-dimensional network structure. Is.

  An air purifying filter according to claim 20 is the air purifying filter according to any one of claims 1 to 19, and carries at least one of manganese dioxide, cobalt oxide, or a composite oxide of manganese and cobalt. It is characterized by this.

  The air purification filter according to claim 21 is the air purification filter according to claim 20, wherein the manganese dioxide, cobalt oxide, or manganese and cobalt composite oxide is supported by a manganese salt aqueous solution, a cobalt salt aqueous solution, Alternatively, a mixed aqueous solution of a manganese salt and a cobalt salt is attached and heated so as to obtain an oxide.

  Moreover, the air purifying apparatus of the present invention is characterized in that, as described in claim 22, ionizing means is provided upstream of the air purifying filter according to any of claims 1 to 21.

  According to the present invention, it is possible to provide an electric field directly on the filter medium sheet by making both the upstream and downstream sides of the filter medium sheet semiconductive and providing a potential difference between the both surfaces, so even if a relatively low voltage is used. A high collection performance can be obtained, and at the same time, the semiconductive surface becomes a buffer zone, so that a rapid movement of electric charge does not occur and a short circuit can be prevented. In addition, harmful gases such as formaldehyde and captans Gaseous impurity components harmful to the human body including odorous gases are ozone-oxidized, decomposed, converted into harmless gases such as carbon dioxide and water vapor, purified, deodorized and purified, and collected bacteria, An air cleaning filter that can detoxify molds, viruses, and allergens, and can collect and further decompose and detoxify gaseous impurity components that could not be collected by conventional dust filters. It is possible to provide the data.

To achieve claim 1 air cleaning filter described above Symbol object of the present invention have a breathable, the both surfaces of the upstream and downstream of the filter medium sheet for collecting dust contained in the air passing through Harmful from dust and dust collected by the generated ozone, semi-conductive, double-sided semi-conductive filter media sheet, generating ozone by controlling the potential difference between both sides of the double-sided semi-conductive filter media sheet gas in which characterized that you purified into harmless gas ozone oxidation. The semiconductive By slightly through the nature of the charges having an intermediate degree of electrical conductivity of the conductive and insulating, the surface resistance and to 10 of approximately 10 @ 8 Omega / □ or more when expressed It is in the range of 12th power Ω / □ or less. By giving the upstream and downstream surfaces of the filter medium sheet semi-conductive respectively to form a double-sided semi-conductive filter medium sheet, the property of passing a slight amount of charge through each of the upstream and downstream surfaces, that is, providing semi-conductivity Can do. By applying different voltages to the upstream and downstream surfaces to which semiconductivity is imparted, an amount of charge corresponding to the applied voltage is uniformly provided on the entire upstream and downstream surfaces. . By doing so, a uniform potential difference can be given between the upstream surface and the downstream surface of the double-sided semiconductive filter medium sheet.

  For example, when 0 kV is applied to the upstream surface by a high-voltage power source and 2 kV is applied to the downstream surface, a charge corresponding to 0 kV can be provided on the upstream surface and an amount equivalent to 2 kV can be provided on the downstream surface. . At this time, it is preferable to provide conductive terminals on the upstream and downstream surfaces of the filter material sheet, respectively, because charges supplied from the high-voltage power supply can be transferred to the respective surfaces. Since the inside of the double-sided semiconductive filter medium sheet has insulating properties, the charges provided on the upstream and downstream faces respectively do not move through the inside of the double-sided semiconductive filter sheet. Thus, a uniform electric field is formed inside the double-sided semiconductive filter medium sheet by the electric charges uniformly provided so as to stay on the upstream and downstream surfaces. When the double-sided semiconductive filter medium sheet is formed of, for example, an aggregate of fine fibers, the fibers present inside the double-sided semiconductive filter medium sheet are polarized by the action of an electric field, and the surface of the fiber is positively added. Negative charge appears to be biased.

  This positive and negative charge bias creates a strong electric field between the fibers, and the dust that tries to pass between the fibers becomes polarized due to the action of the electric field. When approaching the fiber, it is attracted by the electric charge present on the fiber surface and adheres to and collects on the fiber surface (hereinafter, this collecting action is referred to as fiber polarization collecting action). Here, the distance between the upstream side surface and the downstream side surface of the double-sided semiconductive filter material sheet is very small because it is the thickness of the double-sided semiconductive filter material sheet itself and does not sandwich an air layer or the like. That is, since the distance between the charges provided on the upstream and downstream surfaces of the double-sided semiconductive filter medium sheet is very small, an extremely strong electric field can be created inside the double-sided semiconductive filter medium sheet.

  For this reason, all the actions such as the polarization of the fibers, the electric field formed between the fibers, the polarization of the dust, and the force of the charged fiber surface attracting the dust are increased, and the high collection performance can be obtained. In addition, even if a part of the inside of the double-sided semiconductive filter media sheet becomes conductive due to adhesion of conductive dust, the both sides of the double-sided semiconductive filter media sheet are semiconductive, and the vicinity thereof. Only the region of this region causes a potential drop, and other portions can maintain the potential. Therefore, the collection performance is unlikely to deteriorate. Further, since the conductive path from the conductive portion to the terminal is semiconductive, almost no current flows. Therefore, even if a potential difference is given to both sides of the double-sided conductive filter material sheet, there is an effect that no short circuit occurs.

  Here, by controlling the potential difference applied to both surfaces of the double-sided conductive filter material sheet to a certain value or more, electrons can be emitted from either side of the double-sided conductive filter material sheet and accelerated. The accelerated electrons collide with oxygen molecules in the air and split the oxygen molecules into oxygen atoms. Ozone is obtained by combining oxygen atoms obtained by splitting with other oxygen molecules. Since ozone has a strong oxidizing power, it comes into contact with gaseous impurities containing toxic gases such as formaldehyde and captans, and gaseous forms containing toxic gases such as formaldehyde and captans. Impurity components are oxidized and decomposed by ozone, converted into harmless gases such as carbon dioxide and water vapor, and purified, and odorous gases are also oxidized and deodorized by ozone.

  In addition, the collected particles are oxidatively decomposed by contact with ozone for a long time, and harmful gases such as formaldehyde and captans generated from the collected particles or gaseous impurity components such as odorous gases are made harmless. It has an effect that it can be converted, purified, and deodorized.

  Further, the air purification filter according to claim 2 is the air purification filter according to claim 1, wherein a semiconductive coating material that forms a semiconductive film is applied to both sides of the filter material sheet and dried to dry the filter. It is a sheet. The semiconductive paint is a paint in which a film obtained on the coated surface by applying and drying has semiconductivity. By applying the semiconductive paint only to the surface so as not to penetrate the inside of the filter material sheet, both surfaces of the filter material sheet can be made semiconductive easily and at low cost. Specifically, a method of attaching a semiconductive paint on the surface of the coating roll and transferring it directly to the surface of the filter medium sheet, or spraying the semiconductive paint on the surface of the filter medium sheet by spraying can be mentioned. If necessary, it is dried while heating. By performing this on both sides of the filter medium sheet, a double-sided semiconductive filter medium sheet can be obtained. In addition, a large facility is required, but if it is transferred with a coating roll and put into the belt moving type drying furnace as it is, the work becomes fully automatic, so a large amount of double-sided semiconductive filter media sheets can be easily made. .

  The air purification filter according to claim 3 is the air purification filter according to claim 1, wherein a semiconductive ventilation sheet having air permeability and semiconductivity is provided on both sides of the filter medium sheet, and the double-sided semiconductive filter medium is provided. It is a sheet. Specifically, a semiconductive breathable sheet is obtained by immersing a highly breathable nonwoven fabric in a semiconductive paint, or by applying a semiconductive paint to the nonwoven fabric and drying it, and using this semiconductive breathable sheet as a filter medium The method of sticking on both surfaces of a sheet and making it a double-sided semiconductive filter material sheet is mentioned. As a method of attaching the semiconductive ventilation sheet to the filter medium sheet, hot melt resin powder that is melted by heat is applied to the semiconductive ventilation sheet or filter medium sheet, and heating pressure is applied while bonding the filter medium sheet and the semiconductive ventilation sheet. The method of passing through a roller is mentioned. As another method, there is a method in which a nonwoven fabric coated with a semiconductive paint is attached to a filter material sheet without drying and then dried to attach the nonwoven fabric and the filter material sheet. By obtaining a semiconductive filter medium sheet by such a method, both surfaces of the double-sided semiconductive filter medium sheet can be surely made semiconductive.

  According to a fourth aspect of the present invention, there is provided the air purification filter according to the second or third aspect, wherein a solution containing an ion conductive polymer is used as a semiconductive paint. Examples of the ion conductive polymer include a polymer having a quaternary ammonium salt in the molecular structure. The quaternary ammonium salt has four alkyl groups bonded to the central ammonia atom, and has a positive charge as a whole. Since it has a structure in which anions such as chlorine ions are ion-bonded therewith, it has an ionic conductivity and therefore has a property of passing a slight charge. In addition, since the quaternary ammonium salt having ionic conductivity is included in the molecule in advance, the humidity dependency is small, and a characteristic that allows a slight charge to pass even at low humidity can be secured. . In order to form an ion conductive polymer, there is a method of polymerizing a monomer having a quaternary ammonium salt and an unsaturated carbon bond in the molecular structure, but the quaternary ammonium salt and the unsaturated carbon bond are included in the molecular structure. Examples of the monomer having dimethylamino methacrylate include chloride salt. Dissolve an aqueous solution of dimethylamino methacrylate chloride salt in alcohol, add low molecular weight methyl methacrylate to ensure film-forming properties, and then add a polymerization initiator such as azobisisobutyronitrile to cause a polymerization reaction. Thus, a polymer solution containing a quaternary ammonium salt can be obtained. In addition, it is possible to ensure adhesion to the coated surface by adding a polymer solution obtained by polymerizing a monomer having a carboxyl group such as acrylic acid and an unsaturated carbon bond in the molecule. . Moreover, since the coating film formed on the coating surface is made of a polymer having a large molecular weight, it exhibits water insolubility. The coating film made of the semiconductive paint thus prepared has a feature that it allows a slight charge to pass even at low humidity, and also has water resistance without peeling off from the coating surface.

The air cleaning filter according to claim 5, wherein, in the air cleaning filter according to any one of claims 1 to 4, double-sided semi-conductive filter media sheet upstream and downstream face surface resistance are both 10 of the 8 It is characterized by being not less than the squared Ω / □ and not more than the 12th power Ω / □. It can be evaluated by the surface resistivity how much each of the upstream and downstream surfaces of the double-sided semiconductive filter material sheet has electrical conductivity. Upstream and downstream surfaces respectively of the surface resistance is likely through charge higher conductivity in the case of 8 square Omega / □ of less than 10. Therefore, it becomes easy to cause a short circuit between the upstream surface and the downstream surface through the inside of the semiconductive filter medium sheet. Further, 13 square Omega / □ if higher the conductivity of the upstream and downstream surfaces respectively of the surface resistance is 10 is not easily passed through the charge is low. Therefore, it becomes difficult to provide uniform charges on the upstream and downstream surfaces, respectively, and it is difficult to obtain a strong electric field inside the double-sided semiconductive filter medium sheet. Therefore upstream and can provide a semiconductive through moderately charge by the surface resistance of the downstream-side surface together 10 @ 8 Omega / □ or 12 square Omega / □ or less, and while preventing a short circuit High collection performance can be obtained.

  The air purification filter according to claim 6 is the air purification filter according to any one of claims 1 to 5, wherein the filter material sheet is a glass fiber filter material sheet formed by combining glass fibers with a binder. It is a feature. The glass fiber filter sheet is obtained by binding glass fibers by mixing a glass fiber containing silicon dioxide as a main component into a sheet and attaching a synthetic resin binder such as acrylic latex to dry. The glass fiber is made by blowing glass melted by heating with a centrifugal force or a high-temperature and high-speed flame into a cotton shape, and a fiber diameter in the range of several to several tens of micrometers is often used. Glass fiber is highly insulating and easily polarized greatly depending on the strength of the electric field. Therefore, it gives semi-conductivity to the upstream and downstream surfaces of the glass fiber filter sheet. A strong electric field can be provided in the inside of the double-sided semiconductive filter medium sheet by applying a potential difference to this surface, and high collection performance can be obtained.

  Further, an air purification filter according to claim 7 is an air purification filter according to any one of claims 1 to 5, wherein a resin in which a filter medium sheet is melted is blown off with a high-speed gas fluid to form a fiber. It is a melt-blown filter material sheet formed into a sheet shape. By blowing the molten resin together with the high-speed fluid from the nozzle, the resin becomes finely fibrous. Then, the melt blown filter medium sheet is formed by entanglement of the fibers in a semi-molten state by spraying resin fibers on the screen as they are, and binding the fibers by bringing them to room temperature as they are. Polypropylene is often used as a raw material. The fibers of the meltblown filter material sheet using polypropylene are easily polarized and at the same time have the property of maintaining the polarized state, and therefore attract the charged dust well. A semi-conductive property is applied to each of the upstream and downstream surfaces of the meltblown filter material sheet, and a strong electric field is provided inside the double-sided semiconductive filter material sheet by applying a potential difference between the upstream surface and the downstream surface. In addition, a high collection performance can be obtained, and at the same time, a higher dust collection performance can be obtained when the ionization means is provided on the upstream side.

  The air purification filter according to claim 8 is the air purification filter according to any one of claims 1 to 7, wherein conductive terminals are provided on both surfaces of the double-sided semiconductive filter material sheet so as not to overlap projection. It is characterized by this. In order to provide a uniform and strong electric field inside the double-sided semiconductive filter medium sheet, it is necessary to provide charges uniformly on the upstream and downstream surfaces. For this reason, the upstream and downstream surfaces have conductivity, and a voltage is applied to the terminals provided with a certain distribution to supply charges to the upstream and downstream surfaces through the terminals. Is possible. The closer to the terminal, the easier it is to supply charges. Therefore, it becomes easier to provide a uniform charge on each of both surfaces having semiconductivity than when there is no terminal. Here, when the terminals provided on the upstream and downstream surfaces are provided at the same position across the double-sided semiconductive filter material sheet, that is, at positions where they overlap in a projected manner, the inside of the double-sided semiconductive filter material sheet is insulated. There is a high possibility of causing a short circuit due to destruction. Therefore, it is possible to prevent a short circuit by providing the terminals on the upstream side and the downstream side at different positions across the double-sided semiconductive filter material sheet, that is, positions where they do not overlap in projection.

  An air purification filter according to claim 9 is characterized in that, in the air purification filter according to any one of claims 1 to 8, the double-sided semiconductive filter material sheet is formed in a pleated shape. By using a pleated shape, it is possible to reduce the speed at which air and dust pass through the double-sided semiconductive filter medium sheet, that is, the filter medium passing speed. The smaller the filter passage speed is, the longer it takes for the dust to collect by the polarized fibers, so that the dust is easily collected. Moreover, since the speed which passes the air filter medium becomes small, so that a filter medium passage speed is small, it becomes possible to make small ventilation resistance, ie, pressure loss, of a double-sided semiconductive filter medium sheet.

  The air purification filter according to claim 10 is the air purification filter according to claim 9, wherein the two-dimensional network structure having conductivity is provided in contact with the apexes of the upstream and downstream pleat peaks, and the upstream side In addition, different voltages are applied to the two-dimensional network structure on the downstream side. The apex of the pleats of the double-sided semiconductive filter sheet and the two-dimensional network structure have contact points, and the voltages applied to the respective network structures provided upstream and downstream from this contact point. The electric charge corresponding to is supplied to both the upstream side and the downstream side of the double-sided semiconductive filter material sheet, which have semiconductivity, and provides a strong electric field inside the double-sided semiconductive filter material sheet. Here, the top of the pleats of the double-sided semiconductive filter medium sheet and the two-dimensional network structure are in contact with each other at a plurality of locations, so that the whole top of the pleats will play the same role as the terminals, so that both sides are semiconductive. A uniform charge can be provided on each of the upstream and downstream surfaces of the filter medium sheet. In addition, since the height of the pleat peaks of the double-sided semiconductive filter material sheet is the insulation distance between the two-dimensional network structures provided on the upstream side and the downstream side, the double-sided semiconductive filter material sheet is made pleated. This naturally increases the insulation distance. That is, since the insulation distance of the two-dimensional network structure provided on the upstream side and the downstream side can be increased while providing a uniform charge on each of the upstream and downstream surfaces of the double-sided semiconductive filter sheet, a short circuit is caused. It is possible to easily obtain a structure having no high collection performance.

  The air purification filter according to claim 11 is the air purification filter according to claim 9, wherein the conductive rod-shaped member is provided in contact with the apexes of the upstream and downstream pleat peaks, and the upstream and downstream sides are provided. A different voltage is applied to each of the two-dimensional network structures. Since the rod-like member has a rod-like shape and is not easily deformed, it is easy to ensure contact with the pleat mountain. Moreover, since the shape is a rod and the ventilation resistance is small, the pressure loss can be reduced.

  The air purification filter according to claim 12 is characterized in that, in the air purification filter according to any one of claims 1 to 11, the filter medium sheet or the double-sided semiconductive filter medium sheet has water repellency. . When moisture in the air adheres to the surface of the fibers constituting the inside of the double-sided semiconductive filter medium sheet, the insulation of the fiber surface is lowered and sufficient polarization cannot be obtained. Since the leakage current between both surfaces having semiconductivity is increased and a predetermined potential difference cannot be obtained, the dust collecting performance is lowered. The filter media sheet or the double-sided semiconductive filter media sheet has water repellency to prevent moisture in the air from continuously adhering to the fibers, and to suppress the reduction of the electric field to prevent the collection performance from deteriorating. It becomes possible.

  The air purification filter according to claim 13 is the air purification filter according to claim 12, wherein at least one of organopolysiloxane, fluororesin, and wax on the surface of the fiber of the filter medium sheet or the double-sided semiconductive filter medium sheet. A water-repellent film including one or more types is provided. In order to impart water repellency to the filter medium sheet or the double-sided semiconductive filter medium sheet, a method of attaching a water-repellent component to the fiber surface is effective. Specific examples include organopolysiloxane, fluororesin, and wax. Organopolysiloxane has a structure having a siloxane bond as a main chain and an alkyl group in its side chain. Since the outer side of the molecule is occupied by a hydrophobic group having a weak binding force with water such as an alkyl group, the surface of the membrane does not pull the attached water droplet. Since the water droplets aggregate due to their surface tension, the surface of the film and the water droplet show a large contact angle. For this reason, a film made of organopolysiloxane has high water repellency. Although fluororesins and waxes have different molecular structures, the principle of water repellency is the same, and the surface is occupied by hydrophobic groups, thus showing water repellency. By providing a water-repellent film containing at least one of these components on the surface of the fiber, the surface of the fiber is given water repellency, and moisture in the air is prevented from continuously adhering to the fiber. It is possible to suppress a decrease in insulation on the fiber surface and prevent a decrease in collection performance.

  The air purification filter according to claim 14 is the air purification filter according to claim 13, wherein a water repellent film containing organopolysiloxane is provided on the surface of the fiber of the filter medium sheet or the double-sided semiconductive filter medium sheet. The method is characterized in that an aqueous solution in which an organopolysiloxane and a polymer having a water-soluble group are dissolved is infiltrated into a filter medium sheet or a double-sided semiconductive filter medium sheet and then dried. Specifically, a monomer having an unsaturated carbon bond and an organopolysiloxane in one molecule, such as one-end vinyl group-containing polyorganosiloxane compound or one-end acryloxy group-containing polyorganosiloxane compound, and 2-carboxyethyl acrylate A suitable amount of a monomer having an unsaturated carbon bond and a water-soluble group such as a carboxy group or a hydroxyl group in one molecule such as 1-hydroxyethyl acrylate is dissolved in an organic solvent to polymerize azobisisobutyronitrile. Initiator is mixed to cause polymerization reaction. After completion of the reaction, the organic solvent is removed by heating under reduced pressure, and an aqueous ammonia solution and purified water are added to obtain an aqueous solution of organopolysiloxane and a polymer having a water-soluble group. The viscosity of the obtained polymer aqueous solution can be adjusted by diluting with water. An aqueous solution of polymer adjusted to an appropriate viscosity is infiltrated into the filter medium sheet or double-sided semiconductive filter medium sheet by a method such as immersion, and then dried to dry the organic material on the fiber surface of the filter medium sheet or double-sided semiconductive filter medium sheet. A water-repellent film containing polysiloxane can be provided. This aqueous polymer solution is water-soluble and can be used at low cost because water can be used as a diluent. It also has the advantages of being easy to handle because it does not generate organic gas even during drying, and is environmentally friendly because it does not use organic solvents. .

  The air purification filter according to claim 15 is the air purification filter according to claim 13 or 14, wherein a water repellent film containing a fluororesin is formed on the surface of the fiber of the filter medium sheet or the double-sided semiconductive filter medium sheet. As a method of providing, the filter medium sheet or the double-sided semiconductive filter medium sheet is infiltrated into an aqueous solution in which a polymer having a fluoroalkyl group and a water-soluble group is dissolved, and then dried. Specifically, a monomer having an unsaturated carbon bond and a fluoroalkyl group in one molecule such as 2-perfluoroisononylethyl acrylate, and a molecule such as 2-carboxyethyl acrylate and 1-hydroxyethyl acrylate A suitable amount of a monomer having an unsaturated carbon bond and a water-soluble group such as a carboxy group or a hydroxyl group is dissolved in an organic solvent, and a polymerization initiator such as azobisisobutyronitrile is mixed to cause a polymerization reaction. After completion of the reaction, the organic solvent is removed by heating under reduced pressure, and an aqueous ammonia solution and purified water are added to obtain an aqueous solution of a polymer having a fluoroalkyl group and a water-soluble group. Furthermore, the filter medium sheet or double-sided semiconductive filter medium sheet is obtained by infiltrating the polymer aqueous solution diluted with water to an appropriate viscosity into the filter medium sheet or the double-sided semiconductive filter medium sheet by a method such as immersion, and then drying. It becomes possible to provide a water-repellent film containing a fluoroalkyl group on the surface of the fiber. This aqueous polymer solution is water-soluble and can be used at low cost because water can be used as a diluent. It also has the advantages of being easy to handle because it does not generate organic gas even during drying, and is environmentally friendly because it does not use organic solvents. .

  The air purification filter according to claim 16 is the air purification filter according to any one of claims 13 to 15, wherein the water repellent filter contains a wax on the surface of the fiber of the filter medium sheet or the double-sided semiconductive filter medium sheet. As a method for providing a membrane, the filter medium sheet or the double-sided semiconductive filter medium sheet is infiltrated into an emulsion prepared by mixing melted wax with an emulsifier and warm water, and then dried. Wax is a general term for organic compounds that have a melting point of approximately 40 ° C. or higher, have a low viscosity when melted, and do not decompose, and have a basic water-repellent property because they are hydrocarbons composed of carbon and hydrogen. . Moreover, natural wax obtained from natural materials such as animals and plants, petroleum and coal, semi-synthetic wax obtained by using natural materials for synthesis, and synthetic wax obtained by using compounds such as ethylene and propylene for synthesis are roughly classified. Among them, polyethylene wax, which is a synthetic wax, is often used. Polyethylene wax is produced by obtaining polyethylene controlled to a predetermined molecular weight by polymerization of ethylene monomer or thermal decomposition of polyethylene. The melting point is about 100 ° C. And an emulsion can be obtained by mixing and pressurizing the melted polyethylene wax with warm water and an emulsifier. At this time, emulsification is facilitated by using a highly oxidized modified polyethylene wax having a carboxyl group or a hydroxyl group added to the molecular structure. The emulsion thus obtained is impregnated into the filter medium sheet by dipping or the like, and then dried by impregnating the emulsion into the filter medium sheet or double-sided semiconductive filter medium sheet, and then dried to contain the wax on the fiber surface of the filter medium sheet A water-repellent film can be provided. This wax-containing emulsion is water-soluble and can be used at low cost because water can be used as a diluent. Also, it is easy to handle because it does not generate organic gas even when dried, and it is environmentally friendly because it does not use organic solvents. Have

  The air purification filter according to claim 17 is characterized in that in the air purification filter according to any one of claims 1 to 16, a voltage including an alternating current component is applied between both surfaces of the double-sided semiconductive filter material sheet. Is. When a voltage with only a direct current component is applied, the direction of acceleration of electrons is only in one direction, and only electrons emitted from either side of the double-sided semiconductive filter media sheet are accelerated to convert oxygen molecules into oxygen atoms. Split. In contrast, when a voltage containing an AC component is applied between both sides of the double-sided semiconductive filter media sheet, all of the electrons existing inside the double-sided semiconductive filter media sheet swing within the double-sided semiconductive filter media sheet. As it accelerates, there are many opportunities to collide with oxygen. Therefore, it becomes possible to generate ozone more efficiently. In addition, since it is possible to provide an electric field inside the double-sided semiconductive filter medium sheet even with an alternating current component voltage, it is possible to improve the particle collection performance, but the direct current alternating current and the alternating current component are mixed. When a superimposed voltage is applied between both sides of a double-sided semiconductive filter media sheet, it is possible to always provide a strong electric field inside the double-sided semiconductive filter media sheet, and it is possible to capture dust compared to when only an AC component voltage is applied. It is possible to further improve the collection performance.

  An air purifying filter according to claim 18 is characterized in that in the air purifying filter according to any one of claims 1 to 17, an adsorbent is supported on a double-sided semiconductive filter material sheet. Unlike the particles, the gaseous impurity component is a gas, and its size is at the molecular level. Therefore, the gaseous impurity component can be efficiently collected by supporting the adsorbent having pores of molecular size on the double-sided semiconductive filter medium sheet. The kind of adsorbent is preferably an insulating material such as zeolite. Gaseous impurity components collected by the adsorbent oxidize in contact with ozone generated inside the double-sided semiconductive filter media sheet, are efficiently converted into harmless gas, and harmful gases including odorous gases are purified. It will be deodorized.

  The air purification filter according to claim 19 is the air purification filter according to any one of claims 10 to 18, wherein a honeycomb body carrying activated carbon is used as a conductive two-dimensional network structure. Is. Activated carbon is a kind of adsorbent, and has micropores with a micrometer size inside, mesopores smaller than that, and micropores with a pore size of several angstroms. The surface of the pores is basically hydrophobic, so that nonpolar organic gas can be collected particularly efficiently. And since it is what activated carbon, it has the characteristics of having electroconductivity. Therefore, it is possible to use a honeycomb body carrying activated carbon as an alternative to the conductive two-dimensional network structure. Both sides of the double-sided semiconductive filter media sheet through the honeycomb body supporting activated carbon by connecting the output of the high-voltage power source to the honeycomb body supporting activated carbon and contacting the pleats of the pleated double-sided semiconductive filter media sheet It becomes possible to supply electric charge to. Activated carbon has the effect of reducing ozone to oxygen molecules. Therefore, the gaseous impurity component collected by the activated carbon is efficiently oxidatively decomposed using ozone generated inside the double-sided semiconductive filter material sheet. At the same time, it is possible to prevent ozone from flowing to the downstream side of the air purification filter by reducing the remaining ozone that cannot be reduced.

  An air purifying filter according to claim 20 is the air purifying filter according to any one of claims 1 to 19, and carries at least one of manganese dioxide, cobalt oxide, or a composite oxide of manganese and cobalt. It is characterized by this. Manganese dioxide, cobalt oxide, or a composite oxide of manganese and cobalt has an oxidizing action because the valence of manganese or cobalt as a metal element changes. Therefore, it is often used as an oxidation catalyst for gaseous impurity components. By contacting ozone, ozone is reduced and at the same time the valence of manganese and cobalt atoms themselves increases. Therefore, it becomes possible for manganese dioxide, cobalt oxide, or a complex oxide of manganese and cobalt to obtain oxidizing power by contacting with ozone. At least one of manganese dioxide, cobalt oxide, or a composite oxide of manganese and cobalt in various parts of the air cleaning filter, for example, a double-sided semiconductive filter material sheet, a honeycomb body supporting activated carbon, and the inside of the activated carbon. Oxidizing power is applied to manganese dioxide, cobalt oxide, or a composite oxide of manganese and cobalt by contact with ozone generated by supporting oxidative decomposition of not only gaseous impurities but also collected particles. It becomes possible to convert into harmless gas.

  The air purification filter according to claim 21 is the air purification filter according to claim 20, wherein the manganese dioxide, cobalt oxide, or manganese and cobalt composite oxide is supported by a manganese salt aqueous solution, a cobalt salt aqueous solution, Alternatively, a mixed aqueous solution of a manganese salt and a cobalt salt is attached and heated so as to obtain an oxide. Manganese dioxide, cobalt oxide, or a composite oxide of manganese and cobalt is a gaseous impurity component or particle that is dispersed and supported on the surface and inside of a honeycomb and activated carbon on which a double-sided semiconductive filter sheet or activated carbon is supported. As a result, the gaseous impurity components and particles can be oxidized and decomposed most efficiently. A temperature at which manganese dioxide, cobalt oxide, or a composite oxide of manganese and cobalt can be obtained by heating by immersing a honeycomb carrying double-sided semiconductive filter sheet or activated carbon in a manganese salt or cobalt salt aqueous solution. When oxidized, the semiconductive filter material sheet, the honeycomb supporting activated carbon, and the surface and inside of the activated carbon can be uniformly dispersed and supported.

  Moreover, the air purifying apparatus of the present invention is characterized in that, as described in claim 22, ionizing means is provided upstream of the air purifying filter according to any of claims 1 to 21. A strong electric field is provided inside the double-sided semiconductive filter material sheet constituting the air purifying filter according to any one of claims 1 to 21, and uncharged dust is also captured by the fiber polarization collecting action. Although it is easy to collect, if it is a charged dust, it will receive the polarization | polarization collection effect | action of a fiber more, and will be collected more easily. Since the charged dust has a charge, it receives a Coulomb force from the electric field provided in the gap between the polarized fibers and is attracted to the fibers. Since the Coulomb force acts on the charged dust even at a position away from the surface of the fiber, the charged dust receives a larger collecting action than the uncharged and polarized dust. By providing the ionization means upstream of the air cleaning filter, the charged dust can be passed through the air cleaning filter, and it is possible to obtain a higher collection performance than when the air cleaning filter is used alone. A typical ionization means includes a linear or spinous discharge electrode and a counter electrode. A corona discharge is generated by providing a high potential difference between the discharge electrode and the counter electrode, and the dust is charged using the principle that air ions created by ionizing air molecules near the discharge electrode adhere to the dust. be able to.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Incidentally, these embodiments are merely examples, and the present invention is not limited to these embodiments.

(Embodiment 1)
The upstream surface (hereinafter referred to as “sheet upstream surface 2”) and the downstream surface (hereinafter referred to as “sheet downstream surface 3”) of the filter medium sheet constituted by insulating fibers 1 having a fiber diameter of several to several tens of commas are semiconductive. The front view of the air purification filter 12 which applied the different voltage to the terminal 7 provided in the sheet | seat upstream surface 2 and the sheet | seat downstream surface 3 using the double-sided semiconductive filter material sheet 4 and using the high voltage power supply 5 for an air purification filter. 1 is a side view, and FIG. 2 is a side view taken along the line AB of FIG. 1 to show the polarization state of the fibers 1 existing inside the double-sided semiconductive filter medium sheet (hereinafter referred to as the sheet interior 6). A side sectional view is shown in FIG. The fiber 1 in FIG. 3 has a circular shape as a schematic cross-sectional shape, but actually has an elongated fiber shape. Incidentally, although the sheet downstream surface 3 is hidden in FIG. 1, it is not shown but actually exists.

  The sheet upstream surface 2 and the sheet downstream surface 3 are coated with a semiconductive paint containing a polymer of an ion conductive resin having a quaternary ammonium salt in the molecular structure and dried on the both sides of the filter material sheet, or a highly breathable nonwoven fabric The semiconductivity is imparted by pasting a material obtained by immersing the material in a semiconductive paint and drying it on both sides of the filter medium sheet. At this time, the drying temperature is preferably 100 ° C. or lower in order to protect the filter sheet and the semiconductive film by the semiconductive paint. Since the sheet interior 6 is not given semi-conductivity, it remains an insulator and has a property that it is difficult to pass charges. As the insulating fiber 1, glass fiber or polypropylene fiber as described above is suitable. Then, by applying a voltage of 0 kV to the terminal 7 provided on the upstream surface 2 of the sheet and a voltage of 2 kV to the terminal 7 provided on the downstream surface 3 of the sheet using the high-pressure power source 5 for the air cleaning filter, A voltage of 2 kV is applied to the downstream surface 3. In this way, a charge corresponding to 0 kV is uniformly applied to the entire sheet upstream surface 2 and a charge corresponding to 2 kV is uniformly applied to the entire sheet downstream surface 3, that is, between the sheet upstream surface 2 and the sheet downstream surface 3, that is, A uniform electric field is provided in the interior 6 of the sheet.

  The fibers 1 constituting the sheet interior 6 are polarized as shown in FIG. 3 under the action of an electric field, and an electric field is formed in the gap between the fibers 1. The dust introduced into the air purifying filter 12 by the air flow indicated by the air flow direction 8 is polarized by the action of an electric field when passing through the gap between the fibers 1, and the charge on the surface of the fiber 1 when approaching the fiber 1. It is collected by receiving the polarization collecting action of the fiber 1 that is attracted to and attached to the fiber 1. In order to make the electric field formed in the sheet interior 6 strong, the thickness of the double-sided semiconductive filter medium sheet 4 is preferably 2 mm or less. Here, if the sheet upstream surface 2 and the sheet downstream surface 3 are not semiconductive but have high conductivity, the thickness of the double-sided semiconductive filter medium sheet 4 is as thin as 2 mm or less, and therefore the sheet upstream surface 2 and the sheet downstream surface 3 A short circuit occurs between them, and a predetermined voltage cannot be applied, and an electric field cannot be formed.

In addition, if the sheet upstream surface 2 and the sheet downstream surface 3 are not semiconductive and have high insulation properties, it becomes difficult for the charges to spread, and therefore it is not possible to provide a uniform charge on the entire sheet upstream surface 2 and sheet downstream surface 3. . That is, by making the sheet upstream surface 2 and the sheet downstream surface 3 semiconductive, a structure is provided in which charges are uniformly provided on the entire sheet upstream surface 2 and the sheet downstream surface 3 while preventing a short circuit. The surface resistance of the sheet upstream surface 2 and the sheet downstream face 3 can have an appropriate semiconductive With 10 ^ 12 Omega / □ or less 10 ^ 8 Omega / □ or more.

  Then, an electric potential is supplied between the sheet upstream surface 2 and the sheet downstream surface 3 so as to supply electrons to the seat interior 6 and accelerate the electrons to split oxygen molecules into oxygen atoms and generate ozone. Specifically, by applying a voltage of 0 kV to one of the sheet upstream surface 2 and the sheet downstream surface 3 and a voltage of 3 kV or more to the other sheet, acceleration of electrons capable of generating ozone in the sheet interior 6 is accelerated. Obtainable. Further, when a voltage containing an alternating current component is applied, electrons can be accelerated not only in one direction but also between the sheet upstream surface 2 and the sheet downstream surface 3, so that the opportunity for the electrons to collide with oxygen molecules. And more ozone can be generated efficiently. Specifically, by applying a voltage of 0 kV to one of the sheet upstream surface 2 and the sheet downstream surface 3 and applying an AC voltage of 3 to 6 kVp-p and a frequency of 50 to 1000 Hz to the other, ozone is efficiently generated. Can be generated.

  Further, by applying a cross-flow superimposed voltage including both a direct current component and an alternating current component, ozone can be generated efficiently and at the same time the dust collection performance can be improved. Specifically, a voltage of 0 kV is applied to either the seat upstream surface 2 or the seat downstream surface 3, and a DC voltage of 2 kV and 3 to 6 kVp-p, and an AC voltage of 50 to 1000 Hz are combined with the other. The method of applying a cross-flow superimposition voltage is mentioned.

  The dust collected by the generated ozone can be oxidized and converted into harmless gas such as water and carbon dioxide. It becomes possible to purify the harmful gas generated from the collected dust into ozone-oxidized and harmless gas. In addition, bacteria, molds, viruses, and allergens can be rendered harmless by oxidizing and killing and defunctionalizing the cell walls of fungi and mold collected by the generated ozone, virus spikes and envelopes, and allergen antigenic sites. It becomes possible. In addition, the attached gaseous impurity component can be finally converted into harmless gas such as water and carbon dioxide by oxidative decomposition with ozone.

  Since the gaseous impurity component is a gas, it is difficult to collect more gaseous impurity components with a double-sided semiconductive filter medium sheet that does not have molecular-sized pores. Therefore, an adsorbent that has pores with a molecular size of 1 nanometer for small diameters and 50 nanometers for large ones and a large specific surface area of 300 m2 / g or larger is not shown in the figure. By attaching to the filter media sheet 4, it becomes possible to collect more gaseous impurity components contained in the air. At this time, the adsorbent is preferably non-conductive such as zeolite. Since the pores of the adsorbent are limited, it is impossible to collect gaseous impurity components after a certain amount is collected. However, in the air cleaning filter 12 of the present invention, formaldehyde is collected in the adsorbent. Further, toxic gases such as captans or gaseous impurity components such as odorous gases are oxidized upon contact with the generated ozone, and finally converted into harmless gases such as water and carbon dioxide. Therefore, gaseous impurity components can be collected over a long period of time.

  Also, normally, a potential difference of about 2 kV is applied between the sheet upstream surface 2 and the sheet downstream surface 3 to collect dust and gaseous impurity components, and ozone is generated by periodically applying a potential difference of 3 kV or more as necessary. It is also possible to detoxify the collected dust and attached gas by oxidative decomposition. Ozone is harmful to the human body when it exceeds a certain concentration as specified by the working environment standard value of 0.1 ppm. Therefore, ozone is not normally generated, and it is harmful to the human body by generating ozone only when necessary. An air purifying filter 12 having a low property can be obtained. Moreover, the ozone concentration in the air purifying filter 12 can be increased by controlling the blower or the like when ozone is generated to reduce the amount of air passing therethrough, and oxidative decomposition of collected dust and gaseous impurity components can be achieved. It can be carried out more efficiently, and harmful gases such as formaldehyde and captans or odorous gases are oxidized, purified, and deodorized and purified.

(Embodiment 2)
FIG. 4 is a front view of the air purifying filter 12 in which the linear terminals 7 are provided at positions where they do not overlap projectionally on the seat upstream surface 2 and the seat downstream surface 3 when viewed from the front, and FIG. . Electric charges are transmitted from the terminal 7 connected to the high-voltage power supply 5 for the air purifying filter to the sheet upstream surface 2 and the sheet downstream surface 3 having semiconductivity. The closer to the terminal 7 the higher the rate at which the electric charges are transmitted. Therefore, as shown in FIG. 4, the linear terminals 7 are provided uniformly at approximately equal intervals on the sheet upstream surface 2 and the sheet downstream surface 3, so that the sheet upstream surface 2 and the sheet downstream surface 3 can be quickly and more uniformly. Charges can be provided, and a more uniform and strong electric field can be provided in the interior 6 of the sheet, so that the collection performance can be further improved.

(Embodiment 3)
The two-sided semiconductive filter material sheet 4 is formed into a pleat shape, and a conductive two-dimensional network structure 10 is provided so as to contact the apex 9 of the pleat mountain provided on the upstream side, and the pleat mountain provided on the downstream side. Another two-dimensional network structure 10 having conductivity is provided so as to be in contact with the apex 9 of each, and the upstream and downstream two-dimensional network structures 10 are different by connecting the high-pressure power supply 5 for the air purifying filter. FIG. 6 is a perspective view of the air cleaning filter 12 to which a voltage is applied, and FIG. 7 is a side view thereof. FIG. 8 shows a perspective view of an air purification filter using a honeycomb body supporting activated carbon instead of a two-dimensional network structure. Incidentally, for the sake of easy understanding, the two-dimensional network structure 10 shown in FIG. 6 is drawn away from the apex 9 of the upstream pleat mountain and the apex 9 of the downstream pleat mountain. is doing. By making it pleated, the area of the double-sided semiconductive sheet 4 is increased, and the speed at which air and dust contained in the air pass through the double-sided semiconductive sheet 4, that is, the speed of passing through the filter medium can be reduced. The smaller the filter passage speed is, the longer the time during which the polarization collecting action of the fiber 1 is applied to the dust, so that the dust is easily collected. Further, the lower the filter medium passing speed is, the lower the air passing speed is, so that the ventilation resistance of the filter, that is, the pressure loss can be reduced. Further, the apex 9 of the upstream pleat mountain is in contact with the two-dimensional network structure 10 provided on the upstream side, and the apex 9 of the downstream pleat mountain is a two-dimensional network provided on the downstream side. It contacts the structure 10 at a plurality of locations. Since the portion where the two-dimensional network structure and the pleat peak apex 9 are in contact with each other functions as the terminal 7, the voltage applied to each of the two-dimensional network structures 10 provided on the upstream side and the downstream side. Is supplied to the sheet upstream surface 2 and the sheet downstream surface 3 through the contact portions. Since the apex 9 of the pleat mountain is in contact with the two-dimensional network structure 10 at a plurality of locations, almost all of the apex 9 of the pleat mountain will play the same role as the terminal 7, so that the apex 9 of the pleat mountain It is in the same state as a plurality of linear terminals 7 provided on the upstream sheet surface 2 and the downstream sheet surface 3 at a predetermined interval. Therefore, it is possible to supply charges more quickly and more uniformly to the sheet upstream surface 2 and the sheet downstream surface 3, and a high collection performance can be stably obtained.

  Further, as shown in FIGS. 6 and 7, in order to provide an electric field in the double-sided semiconductive filter medium sheet 4, a different voltage is applied to the upstream and downstream two-dimensional network structures 10 to provide a potential difference. It is necessary that the upstream and downstream two-dimensional network structures 10 are not short-circuited. The insulation distance between the two-dimensional network structure 10 on the upstream side and the downstream side is the same as the height dimension of the pleat mountain formed by the double-sided semiconductive filter medium sheet 4, thereby preventing a short circuit. It is necessary to adjust the required insulation distance, that is, the height dimension of the pleat mountain, depending on the difference in voltage applied to the upstream and downstream two-dimensional network structures, that is, the potential difference, but if the potential difference is 2 kV, the pleats The height of the mountain is preferably 15 mm or more. In this way, the double-sided semiconductive sheet 4 is pleated and the two-dimensional network structure 10 is provided so as to be in contact with the apex 9 of the pleat mountain, thereby preventing a short circuit and enhancing the dust collecting performance. The air purifying filter 12 with reduced pressure loss can be obtained. Here, the shape and material of the two-dimensional network structure 10 are not limited as long as the two-dimensional network structure 10 has air permeability and the surface has sufficient conductivity. Examples include a punching metal having a hole in a metal plate, a lath net, a metal mesh in which a metal wire is knitted so as to provide a lattice, a molded body of a conductive resin formed in a net shape, and the like.

  FIG. 8 shows an air purifying filter using a honeycomb body 17 carrying activated carbon instead of the conductive two-dimensional network structure 10. Incidentally, in order to make the drawing easy to understand, in FIG. 8, the honeycomb body 17 is depicted separately from the apex 9 of the upstream pleat mountain and the apex 9 of the downstream pleat mountain, but in actual contact. The honeycomb body 17 has conductivity because powdered activated carbon is uniformly supported thereon. Therefore, it is possible to apply a voltage to the sheet upstream surface 2 and the sheet downstream surface 3 by applying a voltage in the same manner as the conductive two-dimensional network structure 10, and to provide an electric field in the sheet interior 6. Since the activated carbon has conductivity and at the same time has pores of molecular size, the honeycomb body 17 supporting the activated carbon can collect more gaseous impurity components. Then, when the generated ozone comes into contact with the gaseous impurity component collected by the activated carbon, the gaseous impurity component can be oxidatively decomposed and rendered harmless. In FIG. 8, the honeycomb body 17 is provided on both the upstream side and the downstream side of the double-sided semiconductive filter medium sheet 4, but the honeycomb body 17 is provided on both sides instead of the conductive two-dimensional network structure 10. Even if it is provided only on the upstream side or only on the downstream side of the semiconductive filter medium sheet 4, the same effect can be obtained.

  Although not shown in the figure, at least one of manganese dioxide, cobalt oxide, or a composite oxide of manganese and cobalt is applied to, for example, a double-sided semiconductive filter material sheet, a two-dimensional network structure, or a honeycomb body. Oxidizing power can be imparted to manganese dioxide, cobalt oxide, or a composite oxide of manganese and cobalt by contacting with ozone generated by supporting. Specifically, manganese dioxide, cobalt oxide, or manganese and cobalt composite oxide particles are supported on a double-sided semiconductive filter medium sheet, a two-dimensional network structure, or a honeycomb body, or a manganese salt aqueous solution, a cobalt salt aqueous solution, Alternatively, there is a method in which a mixed aqueous solution of manganese salt and cobalt salt is attached to a double-sided semiconductive filter medium sheet, a two-dimensional network structure, or a honeycomb body and then heated to a temperature at which an oxide is obtained. Examples of the manganese salt and cobalt salt include manganese acetate, cobalt acetate, manganese nitrate, and cobalt nitrate. As a result of thermal superimposition analysis, 300 ° C. in all of manganese acetate, cobalt acetate, manganese nitrate, cobalt nitrate, manganese acetate: cobalt acetate = 1: 2 (molar ratio), manganese nitrate: cobalt nitrate = 1: 2 (molar ratio) It turned out that it becomes an oxide below. Accordingly, by adding each salt aqueous solution and heating to 300 ° C. or lower, the double-sided semiconductive filter medium sheet 2, the two-dimensional network structure 10, or the honeycomb body 17 is coated with manganese dioxide, cobalt oxide, or manganese and cobalt. It becomes possible to support the composite oxide uniformly. The supported manganese dioxide, cobalt oxide, or the composite oxide of manganese and cobalt obtains a strong oxidizing power by coming into contact with ozone, and the collected dust and gaseous impurity components can be oxidatively decomposed. In addition, ozone is reduced to oxygen molecules by contact with activated carbon, manganese dioxide, cobalt oxide, or a complex oxide of manganese and cobalt, so ozone that is harmful at a certain concentration or higher is downstream of the air purification filter 12. It is possible to prevent leakage.

(Embodiment 4)
The double-sided semiconductive filter material sheet 4 is formed into a pleat shape, and three conductive rod-like members 11 are in contact with the apex 9 of the pleat mountain provided on the upstream side, and the pleat mountain provided on the downstream side. Three conductive rod-shaped members 11 are provided on both the upstream side and the downstream side so as to contact the apex 9, and the rod-shaped member 11 provided on the upstream side and the downstream side are connected to the high-voltage power supply 5 for the air purifying filter. FIG. 6 shows a perspective view of the air purification filter 12 in which different voltages are applied to the provided rod-shaped members 11. As shown in FIG. 6, different voltages are applied to the rod-like members 11 provided on the upstream side and the downstream side by the high-pressure power source 5 for the air cleaning filter. Further, the rod-shaped member 11 is in contact with the apex 9 of the upstream and downstream pleat peaks, and the contacted portion plays the same role as the terminal 7. For this reason, electric charges corresponding to voltages applied to the rod-like members 11 provided on the upstream side and the downstream side are supplied to the sheet upstream surface 2 and the sheet downstream surface 3 through the contact points, respectively.

  In order to minimize the pressure loss of the air purification filter 12 while ensuring the collection performance, the rod-like member 11 is preferably thin, and the horizontal opening dimension of the air purification filter 12 shown in FIG. If, for example, the thickness of the bar-shaped member is 4 mm or less, the ratio of the bar-shaped member 11 to the horizontal opening dimension on either the upstream side or the downstream side can be sufficiently reduced to 12/100 or less. The pressure loss of the air cleaning filter 12 can be sufficiently reduced. Further, since the rod-shaped member 11 has high bending strength, it can be surely brought into contact with the apex 9 of the pleat mountain simply by being pressed, and an electric field is surely provided in the sheet interior 6 of the double-sided semiconductive filter medium sheet 4. Is possible. Here, the rod-like member 11 is not limited in its material and shape as long as it has sufficient strength and surface conductivity. For example, as the material, a metal, a molded product of conductive resin containing carbon, or a resin molded product provided with a conductive layer made of a conductive coating such as metal plating or carbon can be applied. As the shape, various shapes such as a cylindrical shape and a prismatic shape can be used as long as strength can be secured.

(Embodiment 5)
FIG. 9 shows a perspective view of an air cleaning apparatus in which ionization means 15 including a linear discharge electrode 13 and a plate-like counter electrode 14 is provided on the upstream side of the air cleaning filter 12 described in the third embodiment of the present invention. The structure of the air cleaning filter 12 is exactly the same as that described in the third embodiment. The ionization means 15 includes a linear discharge electrode 13 and a plate-like counter electrode 14 provided so as to sandwich the linear discharge electrode 13. Both the linear discharge electrode 13 and the plate-like counter electrode 14 are conductive, and different voltages are applied by the high voltage power supply 16 for ionization means. Generally, 0 kV is applied to the plate-like counter electrode 14, and a voltage capable of ionizing air by causing corona discharge is applied to the linear discharge electrode 13. The voltage applied to the linear discharge electrode 13 varies depending on the distance from the plate-like counter electrode 14 and the value of the diameter of the linear discharge electrode 13, but generally the distance is about 8 mm and the diameter is about 100 μm. About 3.5 to 5 kV is preferable. Since an electric field that increases as the distance between the linear discharge electrode 13 and the plate-like counter electrode 14 becomes closer to the linear discharge electrode 13 is provided, a very large electric field is provided in the vicinity of the linear discharge electrode 13. Gas molecules such as nitrogen and oxygen that make up the air are slightly ionized into electrons and positive ions with a positive charge due to ultraviolet rays and radiation, etc., and the air has a charge with electrons and a mass close to it. Minor amounts of ingredients are present. Electrons slightly present in the air are accelerated by a strong electric field near the linear discharge electrode, collide with other non-ionized gas molecules, and ionize the gas molecules. The ionized gas molecules emit electrons to the outside and become positive ions, and the electrons emitted to the outside are accelerated in the same manner as the first accelerated electrons to ionize other gas molecules.

  By repeating this process, many positive ions or negative ions in which gas molecules are combined with electrons are created, and ions having the same polarity as the voltage applied to the linear discharge electrode 13 are repelled and diffused around to a certain speed. The ions having a polarity different from that of the linear discharge electrode 13 receive an attractive force and adhere to the linear discharge electrode 13 to absorb the charge, and return to the original gas molecules. In this way, positive ions or negative ions are generated from the vicinity of the linear discharge electrode 13, and the dust in the air passing through the ionization means 15 is combined with the ions and charged with the same polarity as the ions. The charged dust is introduced into an air cleaning filter 12 provided downstream of the ionization means 15, and is polarized by the fibers 1 when passing through the gaps between the fibers 1 in the sheet interior 6 of the double-sided semiconductive filter material sheet 4. It receives the Coulomb force from the electric field provided in the gap, moves to the surface of the fiber 1 and is collected. Which side of the surface of the positively polarized fiber 1 or the negatively polarized fiber 1 moves depends on the polarity of the charged dust. In addition, since the Coulomb force by the electric field acts along the direction of the electric field even when charged dust is present at a position away from the surface of the fiber 1, any one of the fibers 1 at any position in the gap of the fibers 1. It is drawn toward the surface. Therefore, the air purifier provided with the ionization means 15 in front of the air purifying filter 12 of the present invention has very high dust collection performance. Here, the ionization means 15 is composed of the linear discharge electrode 13 and the plate-like counter electrode 14, but is not limited to this type, and any type can be used as long as dust can be ionized. It can be used suitably. As another form of the ionization means 15, there may be mentioned one constituted by a needle electrode and a counter electrode.

Here, the air purifying filter 12 and the air purifying device described in the third and fifth embodiments of the present invention were actually made, and the collection performance and the pressure loss were measured. The following was created as the air purification filter 12 described in the third embodiment. A glass having an appropriate air permeability obtained by immersing a highly breathable non-woven fabric in a semiconductive paint made of an ionic conductive polymer having a quaternary ammonium salt in the structure and drying it at a temperature of 80 ° C. A double-sided semiconductive filter medium sheet 4 was affixed to both sides of the filter medium sheet. The double-sided semiconductive filter medium sheet 4 was cut into 110 mm × 183 mm, and was alternately folded back and forth every 30 mm in the 183 mm dimension direction. This is fixed to a pleat fixing frame having an opening size of 90 mm × 50 mm, the width is 90 mm, the height is 50 mm, the distance between the pleat peaks is 16.7 mm, the height of the pleat peaks is 30 mm, and the upstream and downstream sides are 3 pleat peaks. Obtain a piece of pleats, and provide a two-dimensional metallic network structure with a grid size of about 2 mm square so that the upstream and downstream sides of the pleats are in contact with the apexes of the pleats 9. Filter 12 was obtained. This was designated as the air purification filter 12 of Example 1. In this case the surface resistance is temperature and humidity-sided semi-conductive filter medium sheet 4 was 9 square Omega / □ of 3.0 × 10 at 25 ° C. 60% of conditions.

  Moreover, although it was the same as the air purifying filter 12 of Example 1, the air purifying filter 12 using the melt-blown filter material sheet made from a polypropylene instead of the glass filter material sheet was created, and it was set as the air purifying filter 12 of Example 2. As a comparative example, the measurement was performed in the same manner as the air purification filter 12 of Example 1, except that no voltage was applied to the two-dimensional network structure 10 provided upstream and downstream, and no potential difference was provided. Was the result of the air purification filter 12 of Comparative Example 1. Moreover, although it is exactly the same as the air purifying filter 12 of Example 2, the measurement is performed when no voltage is applied to the two-dimensional network structure 10 provided on the upstream side and the downstream side and no potential difference is provided, and the results are compared. The result of the air purification filter 12 of Example 2 was taken. Moreover, it is the same as the air purification filter 12 of Example 1, but the air purification filter 12 which made only the glass filter material sheet | seat without sticking a semiconductive ventilation sheet on both surfaces was created, and this was made into the air purification filter 12 of the comparative example 3, and did. In addition, air that is substantially the same as the air purification filter 12 of Example 1 but is bonded to both surfaces of a glass filter material sheet instead of a semiconductive air-permeable sheet is immersed in a conductive paint made of carbon and dried. A clean filter 12 was prepared and used as the air clean filter 12 of Comparative Example 4. Moreover, the shape of the air purifying filter 12 of Example 1 is changed, and a glass filter medium sheet is applied to the downstream side only with a conductive ventilation sheet and nothing is attached to the upstream side. The dimensional network structure is formed into a pleat shape similar to that of the glass filter material sheet, and is provided with an insulating clay-like substance so as to be approximately 2 mm apart from the glass filter material sheet, thereby providing air similar to the air purification filter 12 shown in FIG. What has the layer 104 was created and this was made into the air purifying filter 12 of the comparative example 5. FIG. In FIG. 11, the two-dimensional network structure 10 is not provided on the downstream side, and the voltage of the conductive sheet provided on the downstream side does not change. The air purification filter 12 is provided with a two-dimensional network structure 10 similar to the air purification filter 12 of the first embodiment on the downstream side of the air purification filter 12 in order to make the measurement conditions the same.

  Further, similar to the ionization means 15 shown in FIG. 10, three 90 mm-long linear discharge electrodes 13 made of a tungsten wire having a wire diameter of 100 μm are arranged at equal intervals in 50 mm, and the linear discharge electrodes 13 are connected to each other. The ionization means 15 provided with four plate-like counter electrodes 14 made of a galvanized steel plate having a width of 90 mm, a dimension of 15 mm in the ventilation direction, and a heat of 1 mm so as to be located in the center in the horizontal direction with respect to the ventilation direction. An air purifier provided on the upstream side of the filter 12 was created and used as the air purifier of Example 1. Moreover, the air purifier which provided the same ionization means 15 as the air purifying apparatus of Example 1 in the upstream of the air purifying filter 12 of Example 2 was created, and this was made the air purifying apparatus of Example 2.

  In these air purification filter 12 and air purification device, a voltage of 0 kV was applied to the two-dimensional network structure provided upstream of the air purification filter 12 and a voltage of 2 kV was applied to the two-dimensional network structure provided downstream. Incidentally, although the reason will be described later, the results of applying a voltage of 1.5 kV to the two-dimensional network structure provided on the downstream side with respect to the air cleaning filter 12 of Comparative Example 5 are shown in Table 1 below. Further, the ionization means 15 of the air purifiers of the first and second embodiments has about 3.8 kV for the linear discharge electrode 13 and 0 kV for the plate-like counter electrode 14 so that the discharge current is about 1.2 μA. Each was applied and measured. The flow rate of air flowing through each air purifying filter 12 and air purifying device is 0.081 m 3 / min (passing air velocity of 0.3 m / s with respect to the opening of the air purifying filter 12 having a size of 50 mm × 90 mm, and the filter medium The passage speed was 8.33 cm), and the temperature and humidity conditions during the measurement were controlled at 25 ° C. and 60% by controlling the temperature and humidity in the measurement chamber. Under this condition, the current flowing between the two-dimensional network structures provided on the upstream side and the downstream side of the air purification filter 12, that is, the leakage current was measured. Then, the dust collection efficiency was calculated by measuring the number concentration of dust having a particle size of 0.3 μm or more on the upstream side and the downstream side using a particle counter, and at the same time, the pressure loss under this condition was measured using a differential pressure gauge. The results are shown in Table 1. Table 1 is a table showing performance comparison of leakage current, dust collection efficiency, and pressure loss between Examples and Comparative Examples.

  The air purification filter 12 of the comparative example 1 is a result when no voltage is applied before the air purification filter 12 of the first embodiment is measured, but the air purification filter 12 of the first embodiment is compared with the air purification filter 12 of the first comparative example. Thus, the dust collection efficiency is greatly improved from 44% to 96% without increasing the pressure loss. In addition, the air purification filter 12 of Comparative Example 2 is a result when no voltage is applied before the air purification filter 12 of Example 2 is measured, but the air purification filter 12 of Example 2 is the same as the air purification filter 12 of Comparative Example 2. As compared with the air purification filter, the dust collection efficiency is improved from 46% to 84% without increasing the pressure loss, but not as much as the air purification filter 12 of the first embodiment. Leakage currents are 0.3 μA and 0.2 μA in the air cleaning filter 12 of Example 1 and Example 2, respectively, and are sufficiently small even when a voltage of 2 kV is applied. On the other hand, the dust collection efficiency of the air purification filter 12 of Comparative Example 3 was as low as 46%, which was almost the same as that of the air purification filter 12 of Comparative Example 1. This is presumably because a strong electric field cannot be formed inside the filter medium sheet because both sides of the filter medium sheet are not semiconductive. When a voltage was applied to the air purifying filter 12 of Comparative Example 4 in which a conductive ventilation sheet was attached to both sides of the filter medium sheet, a short circuit occurred at about 1 kV, and a potential difference of 2 kV could not be obtained on both sides of the filter sheet. A voltage of 1.5 kV could be applied to the air purification filter 12 of Comparative Example 5, but a short circuit occurred when a voltage of 2 kV was applied. When a voltage of 1.5 kV is applied, the dust collection efficiency is 84%, and a relatively high dust collection performance is obtained. However, when a short circuit occurs at 1.5 kV, which is a little lower than 2 kV that causes a short circuit, Since it can be said that the state is not strange, it is impossible to stably obtain a high dust collection performance.

  Further, the dust collection efficiency of the air cleaning device of Example 1 was 98.9%, and higher dust collection efficiency than that of the air cleaning filter 12 of Example 1 could be obtained. Moreover, the dust collection efficiency of the air purifying apparatus of Example 2 was 99.9%, and the dust collection efficiency was significantly improved as compared with the air purification filter 12 of Example 2. This is considered to be because the melt blown filter medium sheet is made of polypropylene fibers 1. It can be presumed that the fiber 1 made of polypropylene has the property that it is difficult to eliminate the polarization that has occurred once, that is, the property that it is difficult to release the charge, and therefore it is possible to give a stronger Coulomb force to the charged dust. From these actual evaluations, it has been found that the air cleaning filter 12 and the air cleaning device of the present invention can greatly improve the dust collection performance without increasing the pressure loss and without causing a short circuit.

  Further, when the ozone concentration in the air flowing downstream of the air cleaning filter 12 was measured with an ultraviolet absorption ozone concentration meter, as shown in Table 1, the two-dimensional network provided on the downstream side of the air cleaning filter of Example 1 was used. When a voltage of 2 kV was applied to the structure, no ozone was generated. However, when a voltage of 3 kV was applied, the ozone concentration became 76 ppb when a voltage of 23 ppb and 4 kV was applied. Thus, it was found that ozone capable of oxidizing and decomposing dust and gaseous impurity components can be generated by applying a potential difference of 3 kV or more between the sheet upstream surface 2 and the sheet downstream surface 3.

  The air purifying filter and the air purifying device of the present invention have the effect of significantly improving the dust collecting performance without causing an increase in pressure loss or an electrical short circuit and at the same time oxidizing and decomposing collected dust and gaseous impurity components. Therefore, the present invention can also be applied to an apparatus that is required to have a high collection performance with a low pressure loss over a long period of time, such as an air purification device mounted on an air purifier or an air supply type ventilation fan.

The block diagram which shows the front of the air purifying filter as described in Embodiment 1 of this invention. Configuration diagram showing the side of the air purification filter The figure which shows the mode of polarization inside the sheet | seat in the same air purifying filter The block diagram which shows the front of the air purifying filter as described in Embodiment 2. Configuration diagram showing the side of the air purification filter The block diagram which shows the air purifying filter as described in Embodiment 3. Configuration diagram showing the side of the air purification filter The block diagram which shows the air purifying filter which has the honeycomb body as described in Embodiment 3. The block diagram which shows the air purifying filter as described in Embodiment 4. The block diagram which shows the air purifying apparatus as described in Embodiment 5. Configuration diagram showing a conventional dust collection filter

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fiber 2 Sheet | seat upstream surface 3 Sheet | seat downstream surface 4 Double-sided semiconductive filter material sheet | seat 5 High voltage power supply for air purifying filters 6 Sheet | seat inside 7 Terminal 8 Air flow direction 9 Apex of pleat mountain 10 Two-dimensional network structure 11 Rod-shaped member 12 Air purifying filter DESCRIPTION OF SYMBOLS 13 Linear discharge electrode 14 Plate-shaped counter electrode 15 Ionization means 16 High voltage power supply for ionization means 17 Honeycomb body

Claims (22)

Both sides of the filter sheet that has air permeability and collects dust contained in the passing air are made semi-conductive on both the upstream and downstream sides of the filter medium sheet to form a double-sided semi-conductive filter medium sheet. air cleaning filter, characterized that you purify harmful gases into harmless gases ozone oxidation giving electrostatic position difference is generated ozone, generated from the collected dust and dust by ozone generated during. 2. The air cleaning filter according to claim 1, wherein a semiconductive coating material for forming a semiconductive film is applied to both sides of the filter medium sheet and dried to form a double-sided semiconductive filter sheet. The air purification filter according to claim 1, wherein a semiconductive ventilation sheet having air permeability and semiconductivity is provided on both sides of the filter medium sheet to form a double-sided semiconductive filter medium sheet. The air cleaning filter according to claim 2 or 3, wherein a solution containing an ion conductive polymer is used as a semiconductive paint. According to any of claims 1 to 4, characterized in that the upstream side of the double-sided semi-conductive filter media sheet and the downstream side of the surface resistance is both 10 @ 8 Omega / □ or 12 square Omega / □ or less of Air purification filter. The air purification filter according to any one of claims 1 to 5, wherein the filter medium sheet is a glass fiber filter medium sheet formed by combining glass fibers with a binder into a sheet shape. The air purifying filter according to any one of claims 1 to 5, wherein the filter is a melt-blown filter material sheet formed by entanglement of a melted resin blown with a high-speed gas fluid into a fibrous form. . The air purifying filter according to any one of claims 1 to 7, wherein conductive terminals are provided on both sides of the double-sided semiconductive filter material sheet so as not to overlap in projection. The air purification filter according to any one of claims 1 to 8, wherein the double-sided semiconductive filter material sheet is formed into a pleat shape. A two-dimensional network structure having conductivity is provided in contact with the apexes of the upstream and downstream pleat peaks, and different voltages are applied to the upstream and downstream two-dimensional network structures, respectively. Item 10. The air purifying filter according to Item 9. 10. The air purifier according to claim 9, wherein a conductive rod-shaped member is provided in contact with the apexes of the upstream and downstream pleat peaks, and different voltages are applied to the upstream and downstream rod-shaped members, respectively. filter. The air purification filter according to any one of claims 1 to 11, wherein the filter medium sheet or the double-sided semiconductive filter medium sheet has water repellency. 13. The air according to claim 12, wherein a water repellent film containing at least one of organopolysiloxane, fluororesin, and wax is provided on the surface of the fiber of the filter medium sheet or the double-sided semiconductive filter medium sheet. Clean filter. As a method of providing a water repellent film containing an organopolysiloxane on the surface of a fiber having a filter medium sheet or a double-sided semiconductive filter medium sheet, an aqueous solution in which an organopolysiloxane and a polymer having a water-soluble group are dissolved is used as a filter medium sheet, or 14. The air cleaning filter according to claim 13, wherein the air cleaning filter is dried after infiltrating the double-sided semiconductive filter material sheet. As a method of providing a water-repellent film containing a fluororesin on the surface of the fiber of the filter medium sheet or the double-sided semiconductive filter medium sheet, the filter medium sheet or both sides in an aqueous solution in which a polymer having a fluoroalkyl group and a water-soluble group is dissolved The air purifying filter according to claim 13 or 14, wherein the filter is dried after impregnating the semiconductive filter medium sheet. As a method of providing a water-repellent film containing wax on the surface of a fiber of a filter medium sheet or a double-sided semiconductive filter medium sheet, an emulsion prepared by mixing an emulsifier and hot water into a melted wax, a filter medium sheet, or a double-sided semi-conductive film The air purification filter according to any one of claims 13 to 15, wherein the air filter is dried after impregnating the conductive filter material sheet. The air purifying filter according to any one of claims 1 to 16, wherein a voltage containing an AC component is applied between both surfaces of the double-sided semiconductive filter material sheet. The air purification filter according to any one of claims 1 to 17, wherein an adsorbent is supported on the double-sided semiconductive filter material sheet. The air purification filter according to any one of claims 10 to 18, wherein a honeycomb body supporting activated carbon is used as the two-dimensional network structure having conductivity. The air purifying filter according to any one of claims 1 to 19, which carries at least one of manganese dioxide, cobalt oxide, or a composite oxide of manganese and cobalt. As a method for supporting manganese dioxide, cobalt oxide, or a complex oxide of manganese and cobalt, a manganese salt aqueous solution, a cobalt salt aqueous solution, or a mixed aqueous solution of manganese salt and cobalt salt is attached and heated to obtain an oxide. 21. The air purifying filter according to claim 20, wherein An air cleaning device comprising ionization means upstream of the air cleaning filter according to any one of claims 1 to 21.

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