JP2002102624A - Honeycomb filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a honeycomb filter excellent in functionality and dust collection properties, having a low pressure loss and excellent collection efficiency. SOLUTION: The honeycomb filter is comprises a sheet, which has open gaps consisting of a large number of pleated ridge and tough parts formed thereto, using films each of which contains at least one chemical agent selected from a deodorant, an antibacterial agent, antiviral agent, a gas adsorbent, activated carbon and a photocatalyst. A nonwoven fabric comprising liberated fibers, which are formed by applying fiber liberating treatment to the film containing at least one chemical agent selected from the deodorant, the antibacterial agent, the antiviral agent, the gas adsorbent, activated carbon and the photocatalyst, is used to form the sheet which has open gaps consisting of a large number of pleated ridge and tough parts formed thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a honeycomb filter, and more particularly, to a honeycomb filter which is excellent in functions such as dust collection and deodorization, has low pressure loss, and has high collection efficiency.

[0002]

2. Description of the Related Art As an air filter used for an air conditioner, an air purifier, an automobile, etc., for example, an electret non-woven fabric is formed into a pleated shape, and an air current is passed through the pleated shape.
There is known a device that adsorbs and removes fine particles such as dust and dust in the air by static electricity. In general, a special activated carbon layer is provided for removing odors and the like. As a method for producing an electret nonwoven fabric, for example, a method of forming a nonwoven fabric by a melt blow method using a polyolefin such as polypropylene and applying a high DC voltage to the obtained nonwoven fabric is disclosed in Japanese Patent Application Laid-Open No. Sho 6
No. 0-168511, JP-A-2-197110, and the like. In addition, Japanese Patent Publication No. 56-47299
The publication discloses a technique used as a filter.

[0003] However, the filter using the electretized nonwoven fabric having the above-described structure has a problem in that the pressure loss is limited, and there is a problem that the collection life of the fine particles is short because the fine particles are easily clogged. In order to solve such a problem, a filter in which the above-mentioned electret nonwoven fabric is formed into a honeycomb shape has been proposed (Japanese Patent Publication No. 51-52323, etc.). As shown in the perspective view (a) of FIG. 1 and the partial cross-sectional view (b) of the element, the honeycomb filter A is generally flat on a sheet 1 ′ having a large number of peaks 3 ′ and valleys 4 ′. In this case, the sheets 2 ′ are stacked in multiple stages.

[0004] Such a honeycomb filter has a low pressure loss, reduces the power consumption of home electric appliances, particularly air conditioners, and contributes to energy saving. In addition, the use of an electret nonwoven fabric improves the collection performance. However, all of the functions such as low pressure loss, high collection performance, and deodorization cannot be satisfied, and a filter that meets these requirements is not known.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a honeycomb filter which is excellent in functionality and dust collecting property, has low pressure loss, and is excellent in collection efficiency.

[0006]

According to the present invention, there is provided a deodorant, an antibacterial agent, an antiviral agent,
Provided is a honeycomb filter comprising a sheet having a continuous void formed of a large number of ridges and valleys, using a film containing at least one agent selected from a gas adsorbent, activated carbon, and a photocatalyst.

Further, a nonwoven fabric made of defibrated yarn obtained by defibrating a film containing at least one agent selected from a deodorant, an antibacterial agent, an antiviral agent, a gas adsorbent, activated carbon and a photocatalyst, Provided is a honeycomb filter including a sheet in which a continuous void including a large number of ridges and valleys is formed.

[0008] The honeycomb filter of the present invention is preferably in the form of a honeycomb formed by laminating a flat second sheet on a first sheet composed of the above sheets. Further, it is preferable that the second sheet is a film containing the drug or a nonwoven fabric of defibrated yarn obtained by defibrating the film.

In a preferred embodiment of the honeycomb filter according to the present invention, the first sheet and the second sheet are alternately laminated, and the contact portion between the peak or valley of the first sheet and the second sheet is bonded or fused. It is desirable that they are bonded.

[0010] In the honeycomb filter of the present invention, it is preferable that the sheet is electretized because the filter performance can be enhanced.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a honeycomb filter of the present invention will be described in detail. The honeycomb filter of the present invention is a film containing at least one agent selected from a deodorant, an antibacterial agent, an antiviral agent, a gas adsorbent, activated carbon, and a photocatalyst. (A first sheet) in which continuous voids are formed. The honeycomb structure is preferably formed by laminating the first sheet and a flat second sheet.

The film used in the present invention is a resin film, and the resin is preferably made of a thermoplastic resin in that molding and processing are easy. As the thermoplastic resin, polyolefin, polyester,
Examples thereof include polyamide, polyvinyl chloride, polycarbonate, polyvinyl alcohol, and modified products thereof (having a halogen atom, a carbonyl group, a carboxyl group, a nitro group, and the like in a polymer molecule) and a mixture thereof. Among them, a non-polar polyolefin-based polymer or a polyolefin composition containing the polyolefin-based polymer as a main component is easily electretized, which is described later, and is excellent in persistence of its charge and collection performance. preferable. In the polyolefin composition,
A polyolefin polymer having a small amount of a polar group may be contained.

Examples of the polyolefin polymer having a polar group include: (A) a copolymer of a monomer having a polar group and an α-olefin, for example, pentabromophenyl methacrylate;
Copolymer of 4,6-tribromophenyl methacrylate or the like with α-olefin such as ethylene or propylene; (B) Modification by introducing a polar group into side chain or main chain of polyolefin by oxidation or halogenation A polyolefin, for example, polyethylene or polypropylene, which is oxidized or chlorinated to introduce a carbonyl group, a nitro group, or a chlorine atom in the molecule; (C) a polyolefin or a polymer of the above (B), A modified polyolefin obtained by graft copolymerization of a monomer having a group, for example, a polymer alone such as a modified polyolefin modified with a modified monomer such as an unsaturated carboxylic acid or a derivative thereof, or a mixture thereof is exemplified.

Here, the polyolefin-based polymer or the polyolefin which is a base polymer of the modified polyolefin is a homopolymer of α-olefin, a copolymer of two or more α-olefins, or a copolymer selected from these. A mixture of more than one species. As the α-olefin, for example, ethylene, propylene, 1-butene, 1-pentene, 1-hexene, isopentene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 1-decene, 1-
Hexadecene, 1-octadecene, 1-eicosene and the like can be mentioned.

Specific examples of the polyolefin include polyethylene, polypropylene, poly 1-butene, poly 4-methyl-1-pentene, ethylene / propylene copolymer, ethylene / 1-butene copolymer, ethylene / 4-methyl- Examples thereof include 1-pentene copolymer, propylene / 1-butene copolymer, and 4-methyl-1-pentene / 1-decene copolymer. Among them, polypropylene, poly 1-butene, poly 4-methyl, which are high in strength, easy to adjust to an appropriate melt viscosity, and easy to mold by melt blow method.
1-Pentene is preferred, and polypropylene is particularly preferred because it is inexpensive and easy to mold, and is easily electretized.

When a polyolefin composition containing an unmodified polyolefin and a modified polyolefin is used as the main material of the perforated film, the content ratio of the modified polyolefin / unmodified polyolefin in the polyolefin composition is usually 0.1% by weight. 1 / 99.9-20 / 80
And preferably about 1/99 to 5/95. In addition, the polyolefin composition, in addition to the modified polyolefin and the unmodified polyolefin, various additives, such as an antioxidant, an ultraviolet absorber, a pigment, a dye, a nucleating agent, and a filler within a range that does not impair the purpose of the present invention. Agents, slip agents, anti-blocking agents, lubricants, flame retardants, plasticizers and the like.

A known method can be used for forming the film. For example, a film can be obtained by dry-blending or melt-kneading the above-mentioned chemicals with a thermoplastic resin, and then extruding or blowing a film. The thickness of the film is usually from 10 to 200 μm.

The film used in the present invention is more preferably an electretized film. The electretization treatment can be performed by applying a DC voltage to the film. The value of the applied DC voltage is appropriately selected according to the shape of the electrodes to be used, the distance between the electrodes, etc., the amount of charged charges required for the electretization filter, the processing speed, and the like. For example, when the distance between the electrodes is 8 mm, it can be performed by applying a DC voltage of at least -5 kV, preferably -6 to -30 kV to the film.

The method for applying the DC voltage may be any known method, and is not particularly limited. For example,
A method in which a film is passed between a pair of electrodes to which a DC voltage is applied; a method in which a corona discharge or a pulse-like high voltage is applied to the surface of the film; A method such as a method of applying a voltage can be used.

The electretization of the film may be performed at the time of forming the film, or may be performed after the film is formed. The average surface charge density of the electretized film is
It is usually 1 × 10 ^-11 coulomb / cm ² or more in that it can exhibit sufficient dust collection performance as an electret,
It is preferably at least 5 × 10 ⁻¹⁰ coulomb / cm ² .

[0021] The honeycomb filter of the present invention also comprises a defibrated fiber obtained by defibrating a film containing at least one agent selected from a deodorant, an antibacterial agent, an antiviral agent, a gas adsorbent, activated carbon and a photocatalyst. It is a nonwoven fabric made of yarn, and is made of a sheet (first sheet) in which continuous voids composed of many fold-like peaks and valleys are formed. The honeycomb structure is preferably formed by laminating the first sheet and a flat second sheet.

The defibrating treatment is performed by slitting the film and then stretching, or by stretching and slitting to prepare a stretched tape and defibrating the tape. Next, a web is formed by a dry or wet method, and entangled to obtain a nonwoven fabric. The basis weight of the nonwoven fabric is
Usually 5 to 200 g / m ² , preferably ^{20 to} 100 g / m ²
m ² .

It is more preferable that the nonwoven fabric made of the defibrated yarn has been electretized. The electretization process can be performed in the same manner as in the case of the film.

In the present invention, the film or its defibrated yarn contains at least one functional agent selected from a deodorant, an antibacterial agent, an antiviral agent, a gas adsorbent, activated carbon and a photocatalyst. Examples of the functional agent include activated carbon, charcoal, bamboo charcoal, Otani stone powder, and zeolite having deodorizing and various gas adsorption functions; silver zeolite, copper zeolite, which also has an antibacterial action against various bacteria such as Escherichia coli, MRSA, and Staphylococcus aureus; Titanium oxide (photocatalyst), zinc oxide; various phenols such as catechin and apple polyphenol that have antibacterial and antiviral activity; silica gel, sodium chloride, charcoal, and bamboo charcoal with dehumidifying function; tourmaline and distant / near with negative ion generating function Ceramics having a function of generating infrared rays can be used.

When these agents are powders, they are kneaded into the material used for the production of the film, dissolved or dispersed in a solvent, and contained in the surface of the film or defibrated yarn by coating or the like. Can be. In addition, among these chemicals, those which are formed into fibrous materials are contained as fibers as they are by laminating on a nonwoven fabric made of the defibrated yarn or by blending with the defibrated yarn to use as a nonwoven fabric. Can be.

Further, a film obtained by solidifying a functional fiber, for example, activated carbon fiber, antibacterial fiber (copper, silver, etc.) or the like, a fibrous material composed of surface-coated fiber or mixed fiber, or a functional powder with a binder is the above-mentioned film. It can also be used as

Hereinafter, a production example of the honeycomb filter of the present invention will be specifically described. As shown in FIG. 2A, a sheet made of a film or a nonwoven fabric (which may be electretized) made of a defibrated yarn thereof is continuously bent by a heating roll or the like having peaks and valleys to form a large number of sheets. The first sheet 1 having the ridges 3 and the valleys 4 continuously is manufactured. Then, the first sheet 1, superimposed on the flat second sheet 2, the valleys 4 of the bottom 4 ₁ second sheet 2
Fused or adhered to the surface of
Unit 5 is manufactured. Then, after predetermined number making such unit 5, as shown in FIG. 2 (c), the first unit 5 ₁ and a second unit 5 ₂ stacked, the first unit 5 ₁ a mountain portion 3 of the top portion 3 _1, fused or adhered to the second unit 5 ₂ below the surface, further, the second unit as well 5
Over ₂ by laminating the third unit _3, the second unit 5 ₂
Top of the mountain portion of, fused or adhered to the third unit ₃ of a lower surface.

By repeating the laminating and fusing or bonding steps, a structure having honeycomb-shaped voids 6 is formed.
Here, the first sheet 1 and the second sheet 2 may be the same film or nonwoven fabric or different films or nonwoven fabrics.

In the honeycomb filter of the present invention, the height h (shown in FIG. 1) of the honeycomb is usually 10 mm or less, preferably 0.1 to 5 mm, more preferably 0.2 to 3 m.
m, and the width w of the honeycomb (shown in FIG. 1) is usually 10 mm or less, preferably 0.2 to 5 mm, and more preferably 0.1 mm or less.
5 to 3 mm. In particular, by using the electretized film, the height h and the width w of the honeycomb can be significantly reduced as compared with those using a conventional nonwoven fabric, so that the collection efficiency can be dramatically improved.

Further, the honeycomb filter of the present invention is rich in deodorization and other functions because the film as the filter material or the nonwoven fabric made of the defibrated yarn contains the above-mentioned functional agent.

The honeycomb filter of the present invention is excellent in dust collecting property, low in pressure loss, high in collection efficiency, and has a functional property such as deodorization since the filter material easily contains a functional agent. Rich in It operates household air purifiers and air conditioner air purifier filters that use low-power fans, exhaust cleaner exhaust filters, air purifier filters for large facilities such as hospitals and buildings, and operates bioindustries and precision electronic devices. Clean filters for production equipment and rooms; filters for purifying air from cars, buses, airplanes, etc.
In addition, air conditioning filters for food storage warehouses, rooms, refrigerators, etc .; air conditioning filters for buildings, rooms, etc. for animal breeding;
Gas adsorption filter for exhaust gas from factories, laboratories, equipment, etc .; Adsorption filter for formalin odor peculiar to museums, museums, newly-built rooms, etc .; Suitable for use as a filter such as a filter for adsorption of trace gas in the air taken into clean rooms Is done.

[0032]

Industrial Applicability The honeycomb filter of the present invention has excellent dust collecting properties, low pressure loss, high collection efficiency, excellent functions such as deodorization, various types of air cleaning filters, air conditioning filters, and gas filters. It can be preferably used for an adsorption filter and the like.

[0033]

EXAMPLES <Preparation of Sheet> [Preparation Example 1] Density 0.91 g / cm ³ , MFR (ASTM D12
Titanium oxide powder (Lionite, Lionion, average particle size: 5) was added to 100 parts by weight of homopolypropylene having a 6.5 g / 10 min.
μm) was mixed into an extruder and melted.
A film having a thickness of 14 μm was formed by an inflation film forming method. This film was charged by a charge applying device to which a DC voltage of -20 kV was applied, and then defibrated through a defibrating cutter, and a nonwoven fabric was prepared by a card method to obtain a sheet.

[Preparation Example 2] In the same manner as in Preparation Example 1 except that 5 parts by weight of a deodorant (Dimesho ^™ manufactured by Dainichi Seika Co., Ltd.) was added to 100 parts by weight of polypropylene instead of titanium oxide powder. Then, a nonwoven fabric was prepared to obtain a sheet. [Preparation Example 3] A nonwoven fabric was prepared in the same manner as in Preparation Example 1, except that 1 part by weight of an antimicrobial agent (TBZ manufactured by Hokuko Sangyo Co., Ltd.) was added to 100 parts by weight of polypropylene instead of titanium oxide powder. I got a sheet.

[Examples 1 to 3] Each of the sheets obtained in the above production example was continuously folded using a heating roll having peaks and valleys, from the bottom to the top of the valleys. A first sheet having a height of 2.7 mm and a pitch of 5.0 mm and having a large number of peaks and valleys continuously formed was prepared. This first sheet is superimposed on a flat second sheet of the same sheet,
The contact portion between the bottom of the valley of the first sheet and the surface of the second sheet is bonded using a hot-melt adhesive, and FIG.
The unit shown in FIG. Using the 55 units, a width of 255 m is obtained by the method described in FIG.
m, a filter having a length of 165 mm and a depth of 5 mm. Using this filter, the pressure loss and the collection efficiency were measured, and the deodorizing performance and antibacterial deodorizing performance were also evaluated. Table 1 shows the results.

[Comparative Example] Except that no drug was added,
A nonwoven fabric was produced in the same manner as in Production Example 1, and a sheet was obtained. Using this, a filter was produced in the same manner as in the example, and each measurement and evaluation were performed. Table 1 shows the results.

[0037]

[Table 1]

Measurement of Collection Efficiency The collection efficiency was measured using an apparatus schematically shown in FIG. First, the aerosol generator (manufactured by Nippon Kagaku Kogyo) 21 to N
aCl particles (particle size: 0.3 to 0.5 μm) were supplied through an air filter 22 into a chamber 23 into which clean air was introduced. After the concentration of NaCl in the chamber becomes constant (2 to 6 × 10 ⁶ / cm ³ ), suction is performed in the direction of the arrow by the suction device 24 through the filter sample 25 arranged at the bottom of the chamber 23. NaC on the upstream 26 and downstream 27 sides of the filter sample 25 when the wind speed passing through the filter becomes a constant speed (1 m / sec)
The l particle concentration C _in and C _out, a particle counter (Rion Co. KC-01B) 28a, respectively, determined by 28b, was determined trapping efficiency by the following equation. 29
Is a flow meter, and 30 is a flow control valve. Collection efficiency (%) = (1−C _out / C _in ) × 100

Measurement of pressure loss The measurement was performed simultaneously with the measurement of the collection efficiency using a differential pressure gauge (KD146 manufactured by Yamatake Honeywell). However, the wind speed is 1m / sec
And Deodorizing Performance Using a measurement box and a cigarette smoker described in JEM1467, the filter sample was attached to a commercially available air purifier, and a 1-hour dust collection performance test was performed. A sensory test was conducted by 20 persons for the smell of the cigarette in the measurement box, and evaluated according to the following criteria. ○ The number of persons whose cigarette odor is reduced is 10 or more, and the number of persons whose cigarette odor is not reduced is less than 10 persons. Based on the unified test method by the Evaluation Committee for Antibacterial and Deodorant Performance Textile Products (SEK), Staphylococcus aureus was inoculated on the evaluation sample and nylon standard white cloth (unprocessed), and the number of viable bacteria after 18 hours of culture was counted. The bacteriostatic activity value was determined by the following equation. Bacteriostatic activity value = log B-log CB: Number of bacteria after 18 hours of cultivation of a nylon standard white cloth, C: Number of bacteria of an evaluation sample after 18 hours of culturing. The case where the bacteriostatic activity value was 2.2 or more was evaluated as having antibacterial and deodorant performance, and the case where it was less than 2.2 was evaluated as having no antibacterial and deodorant performance.

[Brief description of the drawings]

FIG. 1A is a perspective view showing a conventional honeycomb air filter, and FIG. 1B is a sectional view of a part of the filter element.

FIG. 2 is a diagram illustrating an example of a method for manufacturing a honeycomb filter according to the present invention.

FIG. 3 is a schematic diagram showing a configuration of an apparatus used for measuring a collection efficiency.

[Explanation of symbols]

A Honeycomb Filter h Honeycomb Height w Honeycomb Width 1 First Sheet 2 Second Sheet 3 Crest 4 Valley 5 Unit 6 Void 21 Aerosol Generator 22 Air Filter 23 Chamber 24 Suction Device 25 Filter Sample 26 Upstream 27 Downstream 28a , 28b Particle counter 29 Flow meter 30 Flow control valve

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) A61L 9/01 A61L 9/01 M 4G069 9/16 9/16 F 4L047 B01D 46/00 302 B01D 46/00 302 53/86 B01J 35/02 J ZAB 35/04 301P B01J 35/02 B32B 3/12 B 35/04 301 D04H 13/02 B32B 3/12 B01D 53/36 H D04H 13/02 ZABJ F term (reference) 4C080 AA05 AA07 BB02 BB05 CC01 HH08 KK08 LL10 MM02 MM05 MM11 4D019 AA01 BA13 BA16 BB03 BB08 BC01 BC05 BC06 BC07 CA01 CB06 4D048 AA22 AB03 BA07X BA41X BB02 BB08 CC38 CC41 CD01 J05B13 J01 J05D 4F100 AA37A AA37B AA37C AD11A AD11B AD11C AK01A AK01B AK01C BA03 BA06 BA08 BA10A BA10C CA30A CA30B CA30C DC02 DD12 B DG15A DG15B DG15C GB32 GB48 JC00 JL08 JL08A JL08B JL08C 4G069 AA03 AA08 BA04B BA48A CA01 CA10 CA17 DA06 EA10 EA21 EE06 FA03 FB58 FB67 4L047 AA14 AA29 BA01 CC12 EA02

Claims (6)

[Claims] 1. A continuous void having a large number of ridges and valleys using a film containing at least one agent selected from a deodorant, an antibacterial agent, an antiviral agent, a gas adsorbent, activated carbon and a photocatalyst. A honeycomb filter made of a sheet formed with. 2. A nonwoven fabric comprising a defibrated yarn obtained by defibrating a film containing at least one agent selected from a deodorant, an antibacterial agent, an antiviral agent, a gas adsorbent, activated carbon and a photocatalyst, A honeycomb filter made of a sheet in which continuous voids consisting of a large number of ridges and valleys are formed. 3. The honeycomb filter according to claim 1, wherein a flat second sheet is laminated on the first sheet made of the sheet. 4. The honeycomb filter according to claim 3, wherein the flat second sheet is a film containing the drug or a nonwoven fabric of defibrated yarn obtained by defibrating the film. 5. The method according to claim 3, wherein the first sheet and the second sheet are alternately laminated, and a contact portion between the peak or valley of the first sheet and the second sheet is fused or bonded. The described honeycomb filter. 6. The honeycomb filter according to claim 1, wherein the sheet is formed into an electret.