JP2020138172A - Air filter unit - Google Patents

Abstract

An object of the present invention is to provide an air filter unit that exhibits a high dust collecting effect and a high deodorizing effect and can be purified with low pressure loss. Kind Code: A1 An electrode section, a pleated air filter (17), a counter electrode layer (29) incorporated in the air filter (17), and an auxiliary counter electrode section (30) arranged in the air filter (17) are provided from the upstream side. A charged fiber layer 18 for collecting particles, an adhesive layer 19 for adhering the charged fiber layer 18 and the base material layer 20, and a base material layer 20 for supporting the shape of the filter from the upstream side of the airflow. 20 contains a chemisorption component, the chemisorption component is an amine compound, the adhesive layer 19 and the pleat holding portion 25 contain a conductive component, the adhesive layer 19 forms a counter electrode layer 29, and holds the pleats. The portion 25 forms an auxiliary counter electrode portion 30 , and the potential difference between the electrode portion and the auxiliary counter electrode portion 30 is larger than the potential difference between the electrode portion and the counter electrode layer 29 . [Selection drawing] Fig. 6

Description

The present invention relates to an air filter unit for the purpose of air purification.

In order to improve indoor air quality, it is necessary to remove particulate matter and chemical substances that are indoor pollutants. Particulate matter includes substances of several tens of μm or more such as dust and pollen, PM2.5 generated from combustion of factory exhaust gas and coal, etc., and when taken into the body, allergic reactions occur, and lung diseases, etc. It becomes a health hazard risk. In addition, chemical substances are compound elements or aggregates thereof, which may cause an unpleasant odor or may pose a carcinogenic risk. Effective removal of these (dust collection, deodorization) is desired for improving the living environment.

Conventionally, in order to effectively remove indoor pollutants, for example, activated carbon having a large specific surface area and pore volume is used in the filter filter medium 101 shown in FIG. 7. As a configuration of this type of filter filter medium 101, the adsorbent 102 is contained in activated carbon or silica gel as the supporting layer 103, sandwiched between the base material 104 and the cover layer 105, and held by the filter to be formed into a pleated shape. Was disclosed (see, for example, Patent Document 1).

However, in the cover layer in which the fibers are permanently polarized by charging treatment to improve the collection performance, particulate matter must be removed by electrostatic force in addition to physical collection, so it is used for the cover layer. The amount of fiber was increased. This caused an increase in pressure loss. In addition, the activated carbon used for deodorization has a large particle size, and when it is sandwiched between filters, the air permeability is lowered and the pressure loss is increased.

On the other hand, there are some that have an electrode portion and the fibers of the cover layer are made of a high-dielectric resin material, and the high-dielectric resin is polarized in an electric field created by the electrode portion to improve the dust collection performance by the fibers of the cover layer. (See, for example, Patent Document 2). Further, a technique is disclosed in which dust collection and deodorization are performed with low pressure loss while using an electrode portion together by using a layer structure in which a cover layer and a deodorizing layer (also serving as an earth layer) are integrated. (See, for example, Patent Document 3).

JP-A-2009-61445 Japanese Unexamined Patent Publication No. 2001-190983 Japanese Unexamined Patent Publication No. 2-63561

In the configuration example of the multi-layer device having the dust collecting function and the deodorizing function using the fiber polarization effect by the electric field, the pressure loss (filter material) when passing through the filter medium single plate due to the bonding of the cover layer and the deodorizing layer. Pressure loss) will increase. Further, if the function of each layer is improved, the thickness of each layer is increased, the pressure loss of the filter is increased, and the air volume of the air purifier is reduced. Therefore, it is necessary to reduce the increase in the pressure loss of the filter medium.

Therefore, an object of the present invention is to provide an air filter unit having a lower pressure loss than the conventional one and improved dust collection and deodorizing efficiency.

Then, in order to achieve this object, the air filter unit according to the present invention includes an electrode portion from the upstream side, a pleated air filter, a counter electrode layer built in the air filter, and an auxiliary arranged in the air filter. The air filter is composed of a counter electrode portion, and has a box shape in which a sheet-shaped filter medium is formed in a pleated shape by a frame body and a pleated holding portion, and the sheet-shaped filter medium is charged to collect particles from the upstream side of the air flow. The base material layer includes a fiber layer, an adhesive layer for adhering the charged fiber layer and the base material layer, and the base material layer supporting the filter shape, the base material layer contains a chemical adsorption component, and the chemical adsorption component is an amine type. It is a compound, and the adhesive layer and the pleated holding portion contain a conductive component, the adhesive layer forms the counter electrode layer, the pleated holding portion forms the auxiliary counter electrode portion, and the electrode portion and the electrode portion. The potential difference between the auxiliary counter electrode portion and the counter electrode portion is configured to be larger than the potential difference between the electrode portion and the counter electrode layer, thereby achieving the intended purpose.

According to the present invention, the air filter is composed of an electrode portion from the upstream side, a pleated air filter, a counter electrode layer built in the air filter, and an auxiliary counter electrode portion arranged in the air filter. The sheet-shaped filter medium has a box shape in which a sheet-shaped filter medium is formed in a pleated shape at the pleated holding portion, and the sheet-shaped filter medium has a charged fiber layer for collecting particles and the charged fiber layer and a base material layer from the upstream side of the air flow. The adhesive layer to be bonded and the base material layer supporting the filter shape are provided, the base material layer contains a chemical adsorption component, the chemical adsorption component is an amine-based compound, and the adhesive layer and the pleated holding portion are provided. Contains a conductive component, the adhesive layer forms the counter electrode layer, the pleated holding portion forms the auxiliary counter electrode portion, and the potential difference between the electrode portion and the auxiliary counter electrode portion is the electrode portion. By making the structure larger than the potential difference between the and the counter electrode layer, the adhesive layer becomes the counter electrode layer, the counter electrode layer is not formed of the fiber non-woven fabric, and the electrode portion and the charged fiber are low in pressure loss. It can have high dust collection performance by the layer and high formaldehyde deodorization performance by the chemically adsorbed component of the base material layer.

Further, in addition to the electric field (E1) formed over the entire surface formed between the electrode portion and the counter electrode layer which is the adhesive layer, the direction along the pleated peak formed between the electrode portion and the pleated holding portion. An electric field (E2) is generated toward. This electric field (E2) can bend the traveling direction of the indoor pollutants flowing into the air filter in the direction along the mountain portion of the pleats, and flows into the charged fiber layer and the base material layer with inertial force. Therefore, the moving distance in the charged fiber layer and the base material layer is increased, and the probability of purification in the layer is improved. Therefore, it is possible to have low pressure loss, high dust collection performance, and high formaldehyde deodorization performance.

A perspective view showing an installed state of the air purifying device according to the first embodiment of the present invention. Sectional drawing of the air purification apparatus of Embodiment 1 of this invention An oblique view of the air filter unit according to the first embodiment of the present invention. Schematic diagram of the air filter unit according to the first embodiment of the present invention Schematic of the air filter according to the first embodiment of the present invention Enlarged view of the cross section of the air filter according to the first embodiment of the present invention. An enlarged schematic view showing a part of the electric field of the air filter unit according to the first embodiment of the present invention. Schematic diagram showing a conventional air filter

The air filter unit according to claim 1 of the present invention includes an electrode portion from the upstream side, a pleated air filter, a counter electrode layer built in the air filter, and an auxiliary counter electrode portion arranged in the air filter. The air filter has a box shape in which a sheet-shaped filter medium is formed in a pleated shape by a frame and a pleated holding portion, and the sheet-shaped filter medium has a charged fiber layer that collects particles from the upstream side of the air flow and the charging. The base material layer includes an adhesive layer that adheres the fiber layer and the base material layer, and the base material layer that supports the filter shape. The base material layer contains a chemically adsorbing component, and the chemically adsorbing component is an amine-based compound. The adhesive layer and the pleated holding portion contain a conductive component, the adhesive layer forms the counter electrode layer, the pleated holding portion forms the auxiliary counter electrode portion, and the electrode portion and the auxiliary counter electrode portion The potential difference between the two is larger than that between the electrode portion and the counter electrode layer.

As a result, the adhesive layer becomes the counter electrode layer, so that the layer of the fibrous nonwoven fabric can be eliminated and the pressure loss can be reduced. In addition to the electric field (E1) formed over the entire surface of the air filter formed between the electrode portion and the counter electrode layer which is the adhesive layer serving as the counter electrode, the pleated holding portion serves as the auxiliary counter electrode portion, thereby forming an electrode. An electric field (E2) that spreads in the direction along the pleated mountain portion formed between the portion and the pleated holding portion is generated. This electric field (E2) can bend the traveling direction of the indoor pollutants flowing into the air filter in the direction along the mountain portion of the pleats, and the charged substances have the inertial force while maintaining the charged fiber layer and the base. Since it flows into the material layer, the moving distance in the charged fiber layer and the base material layer is increased, and the probability of being collected in the layer is improved. Therefore, it is possible to have low pressure loss, high dust collection performance, and high formaldehyde deodorization performance.

The air filter unit according to claim 2 of the present invention, the surface resistivity of the adhesive layer is at 10 ⁸ Ω / □ or less, a surface resistance value of the pleats holding member in the following 10 ⁶ Omega, the pleats holding The surface resistance value of the member is smaller than the surface resistance value of the adhesive layer. □ indicates cm ² .

As a result, conductivity can be obtained as a counter electrode to the electrode portion, so that an electric field (E1) is formed over the entire surface of the upstream surface of the air filter, the effect of fiber polarization of the charged fiber layer is increased, and high dust collection performance is achieved. Can be obtained. Further, since the surface resistance value of the pleated holding member is smaller than that of the adhesive layer, an electric field (E2) is formed in the direction along the pleated peak, and the traveling direction of the indoor pollutants flowing into the air filter is pleated. Since the charged substance flows into the charged fiber layer and the base material layer while having an inertial force, it can be bent in the direction along the mountain, and thus moves in the charged fiber layer and in the base material layer. The distance increases and the probability of purification within the layer increases.

The air filter unit according to claim 3 of the present invention is characterized in that the volume resistivity of the polymer material forming the charged fiber layer is 10 ¹⁶ Ωcm or more and the dielectric loss tangent is 0.001 or less. ..

As a result, the charged fiber layer can stably hold a large amount of electric charges applied during spinning or electret processing, and can maintain a high electric field strength for a long period of time, so that the collection efficiency by Coulomb force is also high. It can be maintained for a long period of time. Even when exposed to a load environment such as dust and water vapor in the atmosphere, the dipoles polarized inside the thick fibers are not easily affected, and the charge release into the atmosphere can be suppressed, and the charging ability is maintained for a long period of time. It is maintained and can exhibit high collection efficiency.

Hereinafter, embodiments of the air filter unit according to the present invention will be described with reference to the drawings. The contents described below are merely examples of implementation, and are not limited thereto.

(Premise example)
In the present embodiment, the mechanism of deodorization by chemisorption will be described by taking formaldehyde, which is a typical indoor pollutant, as an example.

The amine compound provided in the present embodiment causes the following irreversible reaction with formaldehyde.

To give an example of the reaction
R-NH ₂ + HCHO
→ RN = CH ₂ + H ₂ O (shiff base)
2H ₂ NCONH ₂ (urea) + HCHO
→ NN ₂ CONHCH ₂ NHCONH ₂ (dimethylol urea)
NH _2- NH ₂ (hydrazine) + 2HCHO
→ CH ₂ = NN = CH ₂
It reacts like this.

Since these reactions are effective reactions for gas components having an aldehyde group (particle size of ^10-9 m to ^10-10 m), they can also be adapted to reactivity with aldehyde compounds other than formaldehyde. In addition, these reactions are due to chemical adsorption, which is distinct from the physical adsorption mechanism such as activated carbon, and there is no re-release of odorous substances.

(Embodiment 1)
Normally, in the building shown in FIG. 1, particulate matter is taken in from the outside air through the window 1 or generated by human life and floats in the room. Formaldehyde is generated from wallpaper 2 or furniture 3, and has a heavier specific gravity than air, so that formaldehyde exists in a high concentration in the vicinity of the floor 4 indoors.

The air filter unit 6 shown in the first embodiment is provided in, for example, an air purifying device 5 arranged on the floor 4 in the room as shown in FIG. Then, the air purifying device 5 performs an air purifying operation.

As shown in FIG. 2, the air purifying device 5 includes an air filter unit 6 and an air blowing means 8 in the main body casing 7.

The main body casing 7 has, for example, a vertically long box shape, has an intake port 9 of the same size as the air filter unit 6 on the front side of the main body casing 7, and has a square air outlet on the top surface of the main body casing 7. A louver 11 for rectifying the flow of air is provided at the air outlet 10. The air outlet 10 communicates with the discharge port of the air blower 8 at the upper part of the air blower 8.

The blower means 8 is provided in the air passage 12 between the intake port 9 and the air outlet 10, and has a scroll-shaped casing 13, blades 14 which are centrifugal blower fans provided in the casing 13, and the blades 14. It is composed of a motor 15 that rotates the casing.

That is, in the air purifying device 5, when the motor 15 rotates, the blades 14 of the centrifugal blower fan rotate, indoor pollutants are sucked from the intake port 9 into the main body casing 7, and the air filter unit 6 and the air passage 12. The mechanism is such that air is blown to the air outlet 10 via the air blowing means 8, and the contaminated air in the room is purified by the air filter unit 6 and the clean air is blown into the room.

FIG. 3 shows a schematic perspective view of the air filter unit 6, and FIG. 4 shows the configuration of the air filter 17. In the air filter unit 6, the electrode portion 16 is arranged on the most upstream side, and the air filter 17 is arranged on the downstream side thereof. The air filter 17 includes a counter electrode layer 29 as a counter electrode with respect to the electrode portion 16, and further includes an auxiliary counter electrode portion 30.

In the air filter 17, the charged fiber layer 18, the adhesive layer 19, and the base material layer 20 are arranged in order from the upstream side. The adhesive layer 19 exists to bond the charged fiber layer 18 and the base material layer 20.

The adhesive layer 19 forms the counter electrode layer 29.

The electrode portion 16 may have any shape as long as it can ionize air molecules. Examples of the electrode include a needle-shaped electrode, a thorn-shaped electrode, and the like. Further, the wire electrode may be arranged in parallel with the pleated holding portion 25 described later.

The current control between the electrode portion 16 and the adhesive layer 19 may be a few μA or less that causes corona discharge, and there is no limitation as long as air molecules can be ionized even in the vicinity of a dark current region where almost no current flows. The electrodes are connected to a high voltage power source, and a voltage of, for example, 6 kV or less can be applied between the electrodes and the adhesive layer 19.

In the air filter 17, the charged fiber layer 18 and the base material layer 20 are each processed into a pleated sheet-like filter medium 21 in order to reduce the surface wind speed and improve the dust collecting performance and the deodorizing performance during the operation of the air purifying device 5. However, it is more effective to increase the area of the filter medium that contributes to dust collection or deodorization. Therefore, as shown in FIG. 5, the air filter 17 has a pleated shape having a peak portion 22 and a valley portion 23, and a frame body 24 for maintaining the pleated shape and fixing the filter size on the outer periphery thereof. Is provided. The air filter 17 of the present embodiment maintains a box shape by the frame body 24. Further, the pleated holding portion 25 is fixed so that the pitch intervals between the mountain portion 22 and the valley portion 23 forming the pleated shape are uniform. The pleated holding portion 25 connects between the mountain portions 22 adjacent to each other in the direction orthogonal to the ridgeline of the mountain portion 22, or between the valley portions 25 adjacent to each other.

The pleated holding portion 25 forms an auxiliary counter electrode portion 30.

In FIG. 6, each layer forming the sheet-shaped filter medium 21 will be described.

The material of the charged fiber layer 18 is, for example, a polyolefin polymer, a styrene polymer, a polyether polymer, a polyvinyl alcohol polymer, a polyester polymer, a polyimide polymer, a polyimide polymer, or a polyamide imide system. Polymers, urethane-based polymers, epoxy-based polymers, fluorine-based polymers, cellulose-based polymers, acrylic-based polymers, vinyl chloride-based polymers, phenol-based polymers, Teflon (registered trademark), silicon, glass fibers, etc. Materials can be mentioned. It is preferable to use one or a mixture of a plurality of these.

Further, a charge strengthening agent may be added to the charge fiber layer 18. The charge enhancer enhances the positive or negative charge effect. The contents described below are merely examples, and are not limited thereto.

For example, as a charge enhancer that promotes positive charging, benzoguanamine compounds, melamine compounds, polymethylmethacrylate particles, crosslinked polymethylmethacrylate particles, inorganic fine particles, imide compounds, light stabilizers, azine compounds, azine compounds. Examples thereof include direct dyes composed of, niglosin compounds, acidic dyes composed of niglocin compounds, metal salts of higher fatty acids, quaternary ammonium salts, and positively charged toners. Two or more of these may be mixed and used.

In addition, examples of the material that promotes negative charge include fluorine compounds, light stabilizers, polymethylmethacrylate particles, crosslinked polymethylmethacrylate particles, inorganic fine particles, metal fine particles, negatively charged toner, and the like, and two or more of these. May be mixed and used.

There are also materials whose charge polarity can be changed by a charge control agent or a surface treatment agent, and these may be used.

Examples of the method for producing the charged fiber layer 18 include a melt blown method, an electrospinning method, a spun bond method, a thermal bond method, a chemical bond method, and a wet method. In many cases, it is necessary to perform electret processing after fiber formation. is there. When the electrospinning method is used, it is a manufacturing method in which a high voltage is applied in the manufacturing process, so that electretization is not required.

The average fiber diameter of the fibers forming the charged fiber layer 18 is preferably composed of fibers of 50 nm or more and 3000 nm or less. When the fiber diameter is larger than 3000 nm, the ratio occupied by the fiber volume when forming the pores of the charged fiber layer 18 becomes large, which leads to an increase in air resistance, that is, an increase in filter medium pressure loss. Further, when the fiber diameter is smaller than 50 nm, air molecules distort and pass through the network space of the fiber, which causes an increase in filter media pressure loss. Therefore, a fiber diameter of 50 nm or more and 3000 nm or less is preferable.

Further, the charged fiber layer 18 has a high volume resistivity of 10 ¹⁶ Ωcm or more and a dielectric loss tangent of 0.001 or less, which satisfies the condition that the volume resistivity of the polymer fiber forming the charged fiber layer 18 is 10 ¹⁶ Ωcm or more in order to secure the chargeability. It is preferably made into a molecule. The volume resistance value of the charged fiber layer 18 itself measured in accordance with the standards JIS K 6911 (standard based on the Industrial Standardization Law) and ASTM D257 (standard established by the American Society for Testing and Materials) may be 10 ¹⁶ Ωcm or more.

If the volume resistivity is lower than 10 ¹⁶ Ωcm, the charge is insufficiently applied to the fiber when a high voltage is applied, and the collection efficiency is lowered. Further, if the dielectric loss tangent is larger than 0.001, the retention of the electric charge applied to the fiber becomes unstable, and the electric charge is easily released into the atmosphere when exposed to high humidity, that is, water vapor, and is collected. Efficiency is reduced. That is, a polymer having a volume resistivity of 10 ¹⁶ Ωcm or more and a dielectric loss tangent of 0.001 or less is preferable.

The base material layer 20 is formed of fibers containing at least one of glass fiber, pulp fiber, resin fiber, carbon fiber and inorganic fiber. Examples of the method for producing the base material layer 20 include a spunbond method, a dry or wet papermaking method, a melt blown method, a spunbond method, an air raid method, a thermal bond method, and the like, and are not particularly limited.

The basis weight of the base material layer 20 is preferably 50 to 100 g / m ² . If the basis weight is less than 50 g / m ² , the rigidity and softness of the base material layer 20 are lowered, which makes it difficult to reduce the productivity of pleating and maintain the filter shape. If it exceeds 100 g / m ² , the pressure loss of the base material layer 20 becomes large, and the structural pressure loss of the air filter 17 when pleated becomes large, which is not preferable.

The average fiber diameter of the fibers constituting the base material layer 20 is preferably 20 to 80 μm. If the average fiber diameter is less than 20 μm, the strength of the fiber is low and the strength as a reinforcing material is insufficient. Further, as the fiber diameter becomes smaller, more chemisorbent components are attached to the gaps between the fibers than on the fibers, resulting in higher pressure loss, a smaller amount of the adsorbent attached, and easier desorption of the adsorbent. Such a problem arises. On the other hand, if it exceeds 80 μm, the thickness of the base material layer 20 becomes thick and the structural pressure loss of the air filter 17 when pleated becomes large, which is not preferable.

The method of incorporating the chemisorbent component into the base material layer 20 includes a method performed before the formation of the base material layer 20 and a method performed after the formation of the base material layer 20.

As a method before forming the fibers of the base material layer 20, there is a method in which a chemisorbent component is contained in the spinning liquid or the coating liquid at the time of fiber spinning or coating of the base material fiber with a resin or the like. Further, as a method after forming the base material layer 20, a method of dissolving and dispersing a chemisorbent component in a solution, adding a small amount of a surfactant and a binder, and then immersing the base material layer 20 in this liquid, chemicals. Examples thereof include a method of spraying a liquid containing an adsorbing component, a method of applying with a brush or a roller, and the like. Among the above methods, a method of impregnating the chemisorbent component after forming the fibers of the base material layer 20 is preferable. As a result, the surface portion of the base material layer 20 can be in a state in which a large amount of chemisorbent component is contained over a wide range. If the chemisorbent component can be present in a wide range on the surface of the base material layer 20, the contact probability with formaldehyde can be increased and the adsorption performance can be improved.

It is important that the particle size of the chemisorbent component is 10 μm or less. This is because when the particle size is 10 μm or less, the surface area becomes large and the contact probability with formaldehyde can be increased to improve the reactivity, and when the particle size exceeds 10 μm, it becomes difficult to adhere to the fibers of the base material layer 20. Prevents the deodorizing performance from deteriorating due to the cause of powder falling. Further, if the particle size exceeds 10 μm, the planar voids in the fiber diameter forming the base material layer 20 are filled, and the rigidity when pleated is further increased, which causes a pressure loss of the air filter 17. is there.

The amount of the chemisorbent component attached to the base material layer 20 is 10 g / m ² to 30 g / m ² . This is because if the amount of adhesion is less than 10 g / m ² , the deodorizing performance becomes low, and if it is more than 30 g / m ^{2, the} performance deteriorates due to powder dropping and the pressure loss increases due to filling the voids in the base material layer 20. is there.

The adhesive layer 19 is formed when the sheet-shaped filter medium 21 for integrating the charged fiber layer 18 and the base material layer 20 into pleats is produced. As the adhesive, an acrylic binder, a vinyl acetate binder, an olefin binder, a polyurethane binder, or the like can be used, and adhesion by hot melt is easy. In order to make the adhesive layer 19 conductive, a conductive additive is added to the adhesive and used as a conductive adhesive. As the conductive additive, carbon black, tin oxide-based or titanium oxide-based metal oxide fine particles, silver-based metal fine particles, or the like can be used. For example, a vinyl acetate-based binder to which a small amount of carbon black is added is liquefied at a high temperature (eg 130 ° C.), applied to at least one of the charged fiber layer 18 and the base material layer 20, and superposed on the other fiber layer at room temperature. It can be pasted together by cooling. The coating amount is preferably 1 to 5 g / m ² . If it is less than 1 g / m ² , the adhesive may be peeled off, and if it is more than 5 g / m ² , the adhesive layer 19 becomes thicker, blocking the voids in the fibers of the two layers and causing an increase in filter medium pressure loss. The resistivity of the adhesive layer 19 may be a 10 ⁸ Ω / □ or less. □ indicates cm ² .

As a result, sufficient conductivity as a counter electrode can be obtained, so that a high electric field strength can be obtained from the electrode portion, the polarization of the fibers of the charged fiber layer 18 can be increased, and high dust collection performance can be obtained.

In particular, the adhesive layer 19 can be connected to an external ground in order to obtain a stable potential difference from the electrode portion 16. That is, the frame body 24 or a part of the frame body 24 is provided with the frame body conductive portion 26 having conductivity, and the frame body conductive portion 26 and the adhesive layer 19 are bonded with a conductive adhesive. The frame conductive portion 26 can be manufactured by applying a paint containing a conductive additive. The frame conductive portion 26 can be grounded through the ground connection portion 27 provided in the air passage 12. Further, the end portion of the adhesive layer 19 and the ground connection portion 27 may be directly connected without using the frame body 24.

At this time, it is important that the configuration of the air filter 17 is arranged in the order of the charged fiber layer 18, the adhesive layer 19, and the base material layer 20 from the upstream, and the dust collecting performance and the deodorizing performance in the electric field formation are improved. The effect can be fully obtained.

The method of pleating is not particularly limited, as long as the pleated shape formed by the peaks 22 and the valleys 23 can be formed, and the sheet-shaped filter medium 21 is bent by a bending machine (not shown) using a method such as a reciprocating engine or a rotary. The pleated shape may be formed by alternately folding mountain folds and valley folds.

The pleated holding portion 25 is used to keep the distance between the mountain portions 22 constant, and holds the mountain portions 22 in one direction (for example, in the vertical direction of the paper surface). The width of the pleated holding portion 25 is preferably 1 to 3 mm, and if it is thinner than 1 mm, the force for holding the mountain portion 22 is weak and may be peeled off during ventilation. If it is thicker than 3 mm, it hinders ventilation and increases pressure loss. .. The distance between the pleated holding portions 25 is preferably 10 to 50 mm, and if it is smaller than 10 mm, it hinders ventilation and increases the pressure loss. If it is larger than 50 mm, the force for connecting the mountain portions 22 is weak and may be peeled off during ventilation. By the above method, it is possible to connect the valley portion 23, and the pleated shape can be made more stable.

In order to give the pleated holding portion 25 a conductive component, the conductive adhesive used when the adhesive layer 19 is manufactured or when the adhesive layer 19 and the frame conductive portion 26 are bonded to each other may be used as the material of the pleated holding portion 25. The pleated holding portion 25 has a distance from the discharge point 28 (the thorn tip if it is a thorn electrode and the needle tip if it is a needle electrode) on the electrode portion 16 in the direction along the mountain portion 22, but the pleated holding portion 25 holds the pleats. the surface resistance value of the parts 25 and 10 ⁶ Ω / □ or less, by reducing 10 ² Ω / □ or higher than the surface resistance of the adhesive layer 19 the surface resistance value of the pleat retaining portion 25, the discharge point 28 and pleat retention An electric field E2 can be formed with the portion 25. Then, by contacting the pleated holding portion 25 with the frame conductive portion 26, the same effect as that of the adhesive layer 19 can be produced on the pleated holding portion 25.

FIG. 7 is a schematic enlarged view of a part of the horizontal cross section of the air filter 17 and the cross section at one of the discharge points 28 as viewed from above, and is a schematic diagram of the formation of the electric field E1 and the electric field E2. Since the electric field E1 composed of the discharge point 28 and the adhesive layer 19 spreads over the entire surface of the sheet-shaped filter medium 21, an electric field is formed on the surface when viewed from the ventilation direction. On the other hand, the electric field E2 composed of the discharge point 28 and the pleated holding portion 25 is generated toward a predetermined interval position along the ridgeline of the pleated peak portion 22. That is, it causes a bias.

With the above configuration, when the air purifying device 5 is operated, indoor pollutants flow in from the intake port 9 of the air purifying device 5, pass through the air passage 12, and reach the air filter unit 6.

When air passes through the electrode portion 16, air molecules are ionized by an electric field formed by the discharge point 28 and the counter electrode layer 29, or the discharge point 28 and the auxiliary counter electrode portion 30, and indoor pollutants contained in the air are also contained. It is ionized and becomes charged.

After that, it reaches the air filter 17 in the subsequent stage of the electrode portion 16. The air filter 17 includes two layers, a charged fiber layer 18 and a base material layer 20, and the counter electrode layer 29 is composed of an adhesive layer 19, so that the counter electrode layer 29 does not use a layer of a fibrous non-woven fabric and pressure loss. It has the following effects while suppressing the increase. The electric field E1 promotes the polarization of the fibers of the charged fiber layer 18 inside, and the action of the electrostatic force can improve the collection efficiency of the charged particulate matter. In particular, since the charged fiber layer 18 and the counter electrode layer 29 are in close contact with each other, the voltage drop between the discharge point 28 and the charged fiber layer 18 can be reduced, and the fiber polarization effect of the charged fiber layer 18 can be sufficiently obtained.

Further, an electric field E2 is formed along the ridgeline of the mountain portion 22, which is composed of the discharge point 28 and the pleated holding portion 25. Therefore, the inflowing particulate matter moves not only in the ventilation direction but also in the direction along the ridgeline of the mountain portion 22. As a result, the horizontal movement of the substance flowing into the charged fiber layer 18 becomes a synthetic component in the ventilation direction and the direction along the ridgeline of the mountain portion 22, the passing distance is extended, and the probability of being removed is improved. Dust collection performance is improved. This can be expected to have the same effect in formaldehyde adsorption in the base material layer 20 in the subsequent stage. This effect is due to the fact that the pleated holding portion 25, which acts as a counter electrode of the electrode portion 16 in the electric field E2, is close to the charged fiber layer 18, so that particulate matter and formaldehyde move in a direction orthogonal to the ventilation direction. You can apply the force to make it. When the pleated holding portion 25 is separated from the charged fiber layer 18, the charged indoor pollutants collide with air molecules and other indoor pollutants and the inertial force is weakened, so that only the movement in the ventilation direction is obtained, and the effect is obtained. Absent. By the above action, the charged particulate matter is collected by the charged fiber layer 18. Since the particulate matter has a particle size of about ^10-4 m to ^10-5 m, it has a higher probability of being collected in the charged fiber layer 18 than formaldehyde and formaldehyde aggregates.

Formaldehyde and formaldehyde aggregates are polarized by an electric field and charged, but because the particle size ( ^10-9 m to ^10-10 m) is small, they pass through the charged fiber layer 18 and adhere. It flows into layer 19. These are chemically adsorbed by the base material layer 20 capable of removing formaldehyde after passing through the adhesive layer 19 inside the air filter 17. The adhesive layer 19 receives an electrostatic force in a direction orthogonal to the inflow direction due to a potential difference with the fibers constituting the adhesive layer 19, and flows into the base material layer 20 on the downstream side while being deflected. As a result, formaldehyde and the like move in the direction perpendicular to the ventilation direction in addition to the movement in the ventilation direction inside the base material layer 20, and the movement distance increases, so that the chemical adsorbent in the base material layer 20 The probability of being adsorbed by the components is improved.

The air purified by the air filter 17 passes through the air passage 12, passes through the air blowing means 8, and is discharged from the air outlet 10 at the louver 11 in the direction of the wind, thereby releasing the purified air into the room and purifying the indoor air. Do.

The air filter unit and the air purifier using the air filter unit in the present invention make maximum use of the dust collecting function and the deodorizing function using electric force, and are used for indoor chemistry represented by particulate matter and aldehydes in the atmosphere. It can be used as an air filter unit that removes substances with low pressure loss and an air purifier using the air filter unit.

1 Window 2 Wallpaper 3 Furniture 4 Floor 5 Air purifier 6 Air filter unit 7 Main body casing 8 Blower means 9 Intake port 10 Air outlet 11 Louver 12 Air passage 13 Casing 14 Blade 15 Motor 16 Electrode 17 Air filter 18 Charged fiber layer 19 Adhesive layer 20 Base material layer 21 Sheet-shaped filter medium 22 Mountain part 23 Valley part 24 Frame body 25 Pleated holding part 26 Frame body Conductive part 27 Earth connection part 28 Discharge point 29 Counter electrode layer 30 Auxiliary counter electrode part 101 Filter filter medium 102 Adsorbent 103 Support layer 104 Base material 105 Cover layer

Claims (3)

From the upstream side, it consists of an electrode portion, a pleated air filter, a counter electrode layer built in the air filter, and an auxiliary counter electrode portion arranged in the air filter. The air filter is a sheet with a frame and a pleated holding portion. The sheet-shaped filter medium has a box shape in which the shaped filter medium is formed in a pleated shape, and the sheet-shaped filter medium has a charged fiber layer for collecting particles and an adhesive layer for adhering the charged fiber layer and the base material layer from the upstream side of the air flow. The base material layer that supports the filter shape is provided, the base material layer contains a chemically adsorbing component, the chemically adsorbing component is an amine-based compound, and the adhesive layer and the pleated holding portion have a conductive component. Including, the adhesive layer forms the counter electrode layer, the pleated holding portion forms the auxiliary counter electrode portion, and the potential difference between the electrode portion and the auxiliary counter electrode portion is the difference between the electrode portion and the counter electrode layer. An air filter unit with a configuration that is larger than the potential difference. The surface resistance of the adhesive layer is at 10 ⁸ Ω / □ or less, a surface resistance value of the pleats holding member in the following 10 ⁶ Omega, the surface resistance of the pleats holding member than a surface resistance value of the adhesive layer The air filter unit according to claim 1, which is a small value. The air filter unit according to claim 1 or 2, wherein the volume resistivity of the polymer material forming the charged fiber layer is 10 ¹⁶ Ωcm or more, and the dielectric loss tangent is 0.001 or less.