JPH08196829A - Air cleaning filter medium and its production - Google Patents

Abstract

PURPOSE: To produce an air cleaning filter medium having satisfactory deodorizing performance and dust removing performance and excellent also in gas permeability and workability. CONSTITUTION: This filter medium has a two-layered structure formed by integrating a filter medium A consisting of very thin glass fibers, org. fibers of <=20μm fiber diameter and binder fibers with a filter medium B consisting of active carbon fibers, natural fibers and binder fibers and having >=40,000m<2> /m<2> BET specific surface area and has <=10mmH<2> O pressure drop measured at 5.3cm/sec surface wind veloctiy in accordance with JIS B9908. The natural fibers in the filter medium B are preferably fibers of wood pulp, hemp pulp or cotton linter pulp and the filter media A, B are preferably wet nonwoven fabrics.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air cleaning filter medium and a method for producing the same, more specifically, it has both deodorizing performance and medium performance filter medium level dust removing performance, and is used in general rooms such as buildings and houses. The present invention relates to an air cleaning filter medium that can be used as an air cleaning filter in automobiles, airplanes, etc., and a method for manufacturing the same.

[0002]

2. Description of the Related Art In general rooms such as buildings and houses, automobiles, airplanes, etc., harmful gases such as malodors and suspended particles in the atmosphere coexist, and an air cleaning filter medium having both removal performance is available. Often desired. As the air cleaning filter media, non-woven fabrics and filter papers made by mixing organic fibers such as polyester fibers and glass fibers have been conventionally used, but these air cleaning filter media do not have deodorizing performance. In order to impart deodorizing performance, it was necessary to use a filter dedicated to deodorizing together.

As an air cleaning filter medium having both deodorizing performance and dust removing performance, which solves the above problems of the conventional air cleaning filter medium, for example, Japanese Patent Laid-Open No. 62-155914 discloses activated carbon. An air cleaning filter paper in which fibers, ultrafine glass fibers and cellulose fibers are integrated is disclosed. The air-cleaning filter paper is a single-layer structure air-cleaning filter paper characterized in that activated carbon fibers impart deodorizing performance and ultrafine glass fibers impart dust removing performance. As an air purifying filter medium having the same single layer structure, Japanese Patent Laid-Open No. 63-62518 discloses an air purifying filter material in which particles or fibers of a cation exchanger and activated carbon are integrated with an ultrafine glass fiber and a binder. ,Also,
Japanese Unexamined Patent Publication (Kokai) No. 2-115013 discloses a filter paper in which activated carbon fibers and ultrafine glass fibers are integrated by using an adhesive (fibrous polyvinyl alcohol or the like). Further, as an air cleaning filter medium having a two-layer structure, for example, in Japanese Patent Laid-Open No. 2-135141,
There is disclosed an air purification filter in which a non-woven fabric having deodorizing performance supporting fine particulate activated carbon and a breathable reinforced non-woven fabric are integrated.

However, the above-mentioned Japanese Patent Laid-Open No. 62-155.
No. 914, JP-A-63-62518, and JP-A No. 2-115013, deodorizing materials such as activated carbon fibers and ion exchangers, ultrafine glass fibers, and binder are integrated. With a single layer structure air cleaning filter medium, it is not possible to mix sufficient amounts of both deodorizing material and ultrafine glass fiber at the same time, and not only sufficient deodorizing and dust removing performance cannot be imparted, but also a single layer structure. Therefore, since the deodorizing material is also directly exposed to airborne particles in the air, there is a problem that the deodorizing performance is deteriorated due to the adhesion of the particles to the deodorizing material.

On the other hand, in the two-layer air cleaning filter disclosed in Japanese Patent Laid-Open No. 135141/1990, a relatively large amount of a binder such as fibrous polyvinyl alcohol is used to prevent the particulate activated carbon from falling off. It must be used, and not only the effective specific surface area is reduced due to the fine pore activated carbon coating with a binder, but a large amount of fine activated carbon is blended when considering the strength of the filter medium, air permeability of the filter medium, and papermaking properties. It is difficult to do so, in order to increase the specific surface area per unit area of the filter medium, it is unavoidable to use a high basis weight filter medium, and the thickness of the filter medium increases and the filter medium area cannot be increased when it is incorporated into the unit. However, there is a problem in that the fine-grained activated carbon falls off due to cutting, etc. and the workability is poor. In addition, according to the publication, it is preferable that the breathable reinforced nonwoven fabric has a thin and rough structure in order to avoid a decrease in breathability of the filter medium, and sufficient dust removing performance is obtained in the nonwoven fabric layer. Is difficult.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems, has excellent breathability, has both deodorizing performance and dust removing performance at the level of a medium-performance filter medium, and has further processability. It is also an object of the present invention to provide an air cleaning filter medium excellent also in the above and a manufacturing method thereof.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the inventors have invented an air cleaning filter medium and a method for producing the same.

That is, the air cleaning filter medium of the present invention comprises ultrafine glass fibers, organic fibers having a fiber diameter of 20 μm or less,
And filter material A composed of a binder fiber, and activated carbon fibers, natural fibers and is composed of binder fibers, and a two-layer structure in which the BET specific surface area per 1 m ² are integrated 40,000 m ² or more medium B, Nari, JIS B9
According to 908, the pressure loss measured at a surface wind velocity of 5.3 cm / sec has a value of 10 mmH ₂ O or less.

In the air-cleaning filter medium of the present invention, the natural fiber is preferably at least one selected from the group consisting of wood pulp, hemp pulp and cotton linter pulp.

Further, in the air cleaning filter medium of the present invention, it is preferable that the filter medium A or the filter medium B is a wet non-woven fabric.

In the method for producing an air cleaning filter medium of the present invention, ultrafine glass fibers, organic fibers having a fiber diameter of 20 μm or less, and binder fibers are mixed in water to prepare an aqueous slurry, and the aqueous slurry is prepared by a wet papermaking method. The filter medium A produced by using the activated carbon fiber, the natural fiber, and the binder fiber are mixed in water to prepare an aqueous slurry, and the filter medium B produced by using the aqueous slurry by a wet papermaking method.
It is characterized in that and are combined and integrated, and dried.

The air cleaning filter medium of the present invention will be described in detail below.

First, the filter medium A will be specifically described below. The filter medium A constituting the air cleaning filter medium of the present invention is a filter medium having a dust removing performance mainly for capturing and removing suspended particles in the air with ultrafine glass fibers. The filter medium A will be described through a specific description of the fibers used in the filter medium A.

The ultrafine glass fiber used in the present invention is
It is a glass fiber having an average fiber diameter of 0.2 to 4 μm and is a fiber that determines the dust removal performance. The blending amount of the ultrafine glass fiber is preferably 3 to 20% of the weight of the filter medium A, and more preferably 5 to 15%. If it is less than 3%, sufficient dust removal performance cannot be obtained. On the other hand, if it exceeds 20%, the dust removal performance is improved, but not only the papermaking property is deteriorated due to a decrease in drainage, but also an air cleaning filter. It is not preferable because the air permeability of the filter material is lowered.

Next, the organic fiber will be described below. The organic fiber used in the present invention has a fiber diameter of 20 μm.
It is a fiber of m or less. Since the organic fiber is highly flexible and easy to bend, it not only entangles well with the ultrafine glass fiber which is rigid and does not have self-adhesion ability and effectively acts to form a uniform network, but the diameter of the organic fiber is 20 μm or less. Since it forms a fine and dense network, it is also excellent in retaining ultrafine glass fibers.

Therefore, by using the organic fibers, good dust removing performance can be obtained even when the amount of the ultrafine glass fibers is small, so that good dust removing performance can be imparted without impairing the air permeability of the filter medium. it can. If the fiber diameter of the organic fibers is larger than 20 μm, the number of organic fibers in the filter medium decreases, and a coarse network is formed.
The retention capacity of the ultrafine glass fiber by the organic fiber is reduced,
Since the amount of ultrafine glass fibers flowing out from the wire during papermaking increases, sufficient dust removal performance cannot be obtained, and the yield of expensive ultrafine glass fibers decreases, which is also unfavorable in economic efficiency.

The type of organic fiber is not particularly limited as long as it has a fiber diameter of 20 μm or less. Polyamide fiber, polyester fiber, polyacrylonitrile fiber, polyethylene fiber, polypropylene fiber, Fibers selected from synthetic fibers such as polyvinyl alcohol fibers, phenol fibers, recycled fibers and natural fibers such as wood pulp, hemp pulp and cotton linter pulp can be used alone or in combination.

The fiber length of the organic fiber is preferably 1 to 20 mm, more preferably 3 to 6 mm. When the length is shorter than 1 mm, it becomes a dense filter medium, and not only the air permeability is lowered, but also the drainage of the slurry is lowered and the productivity is deteriorated, which is not preferable. If the length is more than 20 mm, the dispersibility in water is deteriorated, and a uniform filter material having a good texture cannot be obtained, which is not preferable.

The amount of the organic fiber blended is 20 times the weight of the filter medium A.
˜70% is preferable, and more preferably 30-50%. When it is less than 20%, the number of organic fibers in the filter medium decreases, and the ability to form a network with the ultrafine glass fibers decreases, so that sufficient dust removal performance cannot be obtained, which is not preferable. When it is more than 70%, the amount of binder fiber to be described later becomes small, the strength of the filter medium is lowered, and the processability becomes poor, which is not preferable.

Next, the binder fiber will be described below. As the binder fiber used in the present invention,
Examples are heat-meltable fibers and hot-water-soluble fibers.

The heat-fusible fiber is a fibrous material selected from synthetic resins such as polyester, polyolefin and polyamide, and the synthetic resin is melted when treated at a temperature higher than the melting point of the synthetic resin to improve adhesion and strength. It will be expressed.

The hot water-soluble fiber is a fibrous material selected from synthetic resins such as polyvinyl alcohol and ethylene vinyl alcohol, and is melted by increasing the water temperature in the step of drying the wet web by heating to form a web. When dried, it exhibits adhesion and strength.

The fineness of the binder fiber is preferably 0.1 to 15 denier. When it is less than 0.1 denier, the drainage of the slurry becomes small and the productivity is deteriorated, which is not preferable. If it is larger than 15 denier, the number of binder fibers in the filter medium will decrease, and the amount of binder fibers must be increased in order to compensate for the decrease in adhesive strength, and not only the amount of other constituent fibers will decrease. However, the water content of the web at the time of paper making becomes small and it becomes difficult to pick up from the wire, which is not preferable.

The fiber length is preferably 1 to 20 mm, more preferably 3 to 6 mm. If it is shorter than 1 mm, it becomes a dense filter medium and the air permeability is lowered, which is not preferable. Two
When the length is more than 0 mm, the dispersibility in water is deteriorated, and a uniform filter material having a good texture cannot be obtained, which is not preferable.

The content of the binder fiber is preferably 30 to 60% of the weight of the filter medium A, more preferably 40 to 60%.
50%. If it is less than 30%, the adhesive strength is insufficient and the strength of the filter medium is lowered, which is not preferable. If it is more than 60%, the adhesive force is large, but the amount of the other constituent fibers is decreased, and the filter material is inferior in dust removal performance, which is not preferable.

Next, the filter medium B will be specifically described below. The filter medium B of the present invention is a filter medium that adsorbs and removes malodorous gas and the like by activated carbon fibers, and the BET specific surface area of the filter medium B is greatly involved in deodorizing performance. The filter medium B will be described in detail below through the description of the fibers used for the filter medium B.

The activated carbon fiber used in the present invention is a fiber which determines the BET specific surface area of the filter medium B, and widely used conventionally known ones produced from recycled fiber, phenol fiber, polyacrylonitrile fiber and the like as precursors. can do. The specific surface area of the activated carbon fiber is not particularly limited, but when the specific surface area is too large, the strength of the single yarn becomes small, the disintegration at the time of paper making, the stirring share in the dispersion step, and the addition at the press part. The specific surface area is preferably 2,500 m ² / g or less because fiber damage easily occurs due to pressure and the like to generate fine powder of activated carbon fibers.

Although the fiber diameter and fiber length of the activated carbon fiber are not particularly limited, the average fiber diameter is preferably 5 to 30 μm in view of drainage property and fiber dispersibility during paper making, while the average fiber length is Is preferably 1 to 20 mm, more preferably 3 to 6 mm.

The BET specific surface area per 1 m ^{2 of} the filter medium B is 40,000 m ² though it depends on the adsorption characteristics of the activated carbon fiber used.
If it is above, it is possible to secure the benzene adsorption amount used as one of the indicators of the deodorizing performance of 15 g / m ² or more, and sufficient deodorizing performance can be obtained. Therefore, the BET specific surface area is within the range. The amount of activated carbon fiber is not particularly limited as long as it is within the range. However, if the content of the activated carbon fibers exceeds 90% of the weight of the filter medium B, the content of the natural fibers described below is decreased and the active carbon fibers are more likely to fall off. Is preferably 90% or less of the weight of the filter medium B.

Next, the natural fiber will be described below. The natural fiber used in the present invention effectively retains the activated carbon fiber having no self-adhesion ability and is used for forming into a sheet, and conventionally known plant fibers can be widely utilized. . Since the natural fiber is highly flexible, it is entwined well with the activated carbon fiber which is rigid and has no self-adhesion ability to form a uniform network, so that the activated carbon fiber can be effectively and firmly retained even in a relatively small amount. It is possible to mold the activated carbon fiber into a sheet without inserting the filter medium to densify it. When a binder fiber typified by a heat-meltable fiber or a hot-water-soluble fiber is used for forming the activated carbon fiber into a sheet, the fusion of the binder fiber blocks the micropores on the surface of the activated carbon fiber. Therefore, the performance deterioration of the activated carbon fiber due to this is inevitable, but when the natural fiber of the present invention is used, there is an advantage that such a performance deterioration of the activated carbon fiber is almost zero. Further, the activated carbon fiber sheet adhered only by the binder fiber has a problem that the paper layer peeling easily occurs in the activated carbon fiber sheet during the pleating process, and in order to solve this, the micropores of the activated carbon fiber are closed. Although the blending amount of the binder fiber had to be increased, the natural fiber of the present invention has such self-adhesive ability and is well entangled with the activated carbon fiber as described above. There are no problems. In addition, the use of the natural fiber strengthens the strain of the filter medium and improves the processability.

The type of natural fiber is not particularly limited as long as it is a vegetable fiber, but wood pulp, hemp pulp and cotton linter pulp are inexpensive and easily available, and are like those of beaters and refiners. Since the specific surface area of the fiber can be adjusted by beating with an ordinary beating machine, it is also possible to arbitrarily adjust the retention performance of the activated carbon fiber by the fiber and the air permeability of the filter medium. It is a particularly preferable material because it has excellent properties.

The blending amount of the natural fiber is 5 to the weight of the filter medium B.
It is preferably 50%, more preferably 20-40%. If it is less than 5%, the ability to retain the activated carbon fibers is insufficient, and the activated carbon fibers are significantly detached, which is not preferable. Fifty
When it is more than 0.1%, the activated carbon fiber holding capacity is large, but it becomes a dense filter medium and a filter medium lacking air permeability, which is not preferable.

Next, the binder fiber will be described below. As the binder fiber used in the present invention,
The heat-meltable fiber or the hot-water-soluble fiber exemplified in the above filter medium A can be utilized. In the filter medium B, the binder fiber also participates in the adhesion of the activated carbon fiber, but it is mainly used for the purpose of developing the interlaminar strength when the filter medium A and the filter medium B are laminated and integrated.

The content of the binder fiber is preferably 3 to 20% of the weight of the filter medium B. If it is less than 3%, the interlaminar adhesive strength becomes insufficient, and delamination occurs during pleating, which is not preferable. On the other hand, 20%
If it is more than 1.0, the interlaminar adhesive strength increases, but the fusion of the binder fibers blocks the micropores of the activated carbon fibers and impairs the characteristics thereof, which is not preferable.

The air cleaning filter medium of the present invention is obtained by integrating the filter medium A and the filter medium B described above. The filter medium can be used as a medium-performance filter medium having a deodorizing performance, and in order to be a filter medium suitable for practical use, it needs to have air permeability comparable to that of the medium-performance filter medium. Pressure loss measured at a wind speed of 5.3 cm / sec is 10 mmH ₂ O
Must be: If the pressure loss exceeds this value and is large, operating costs increase, the life of the filter medium decreases, and noise during use increases, which is not preferable.

Next, a method for producing the air cleaning filter medium of the present invention will be described below. First, the essential components of the filter medium A are sequentially added to water to prepare an aqueous slurry. The order of adding the fibers is not particularly limited, but the fiber concentration of the aqueous slurry is 0.
It is preferably from 1 to 5% by weight. Then, the aqueous slurry of the filter medium B is also prepared by the same method.

A filter machine A is prepared from the aqueous slurry by using a combination machine which is a combination of two paper machines such as ordinary paper and wet non-woven fabric, for example, fourdrinier paper machine, cylinder paper machine and inclined wire paper machine. And a filter medium B are combined to form a web, which is pressed and dried to produce an air cleaning filter medium. A cylinder dryer, a Yankee dryer, an air dryer or the like can be used to dry the web.

[0038]

The air cleaning filter medium of the present invention has a two-layer structure in which the filter medium A having dust removing performance and the filter medium B having deodorizing performance are integrated.

In the filter medium A, the ultrafine glass fibers are well entangled with the organic fibers having a fiber diameter of 20 μm or less to form a uniform and dense network, and excellent dust removal performance is obtained even when the amount of the ultrafine glass fibers is small. Therefore, it is possible to obtain a filter medium excellent in dust removal performance without impairing air permeability.

On the other hand, in the filter medium B, the activated carbon fibers having a high adsorption rate are firmly held by the natural fibers without blocking their micropores, the activated carbon fibers are less likely to fall off, and the BET specific surface area is small. It is possible to obtain a filter medium having a large size, and by using the natural fiber, the strain of the filter medium becomes strong and the processability is improved.

Therefore, since the air cleaning filter medium of the present invention is excellent in both deodorizing performance and dust removing performance, and is also excellent in breathability and workability, it is processed into various structures such as honeycombs and folds, Effectively works as an air purifying filter medium in general rooms such as buildings and houses, automobiles, airplanes, etc.

[0042]

The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

Examples 1 to 10 [Preparation of filter medium A] Extra fine glass fiber (average fiber diameter 0.6 μm)
m), polyester fibers (fiber diameters 7 μm, 14 μm, 18 μm, fiber length 5 mm) as organic fibers having a fiber diameter of 20 μm or less, and core-sheath type heat-fusible polyester fibers (fiber diameter 14 μm, fiber length 5 mm, sheath) as binder fibers. Partial melting point 110 ° C.) Fiber blend shown in Table 1 below (described in wt%)
To prepare an aqueous slurry, and a filter material A having a basis weight of 60 g / m ² was prepared from these slurries by using a square handmade paper machine.

[Preparation of filter medium B] Activated carbon fiber (nominal specific surface area: 950 m ² / g), natural fiber softwood bleached kraft pulp (freeness 550 ml), hemp pulp (640 m)
1), cotton linter pulp (same as 610 ml), and core-sheath type heat-fusible polyester fiber (fiber diameter 14 μm, fiber length 5 mm, sheath melting point 110 ° C.) as a binder fiber, mixed in a fiber formulation shown in Table 1 Slurries were prepared and the basis weight of these slurries was 10 using a square handmade paper machine.
A filter medium B of 0 g / m ² was prepared.

[Preparation of Filter Material for Air Cleaning Filter] Filter material A and filter material B in the form of wet paper are combined and integrated, then pressed and dried to obtain the filter materials for air cleaning filter of Examples 1-10. It was made.

Comparative Example 1 Comparative Example 1 was carried out in the same manner as in Examples 1 to 3 except that polyester fibers having a fiber diameter of more than 20 μm (fiber diameter 25 μm, fiber length 5 mm) were used as the organic fibers of the filter medium A.
The air cleaning filter material of No. 3 was produced.

Comparative Example 2 In the filter medium B, activated carbon fiber (nominal specific surface area 950 m ²
/ g) 70% by weight, softwood bleached kraft pulp (freeness 5
Except that 50 ml) was mixed with 30% by weight of fiber,
An air cleaning filter medium of Comparative Example 2 was produced in the same manner as in Example 1.

Comparative Example 3 In the filter medium B, activated carbon fiber (nominal specific surface area 950 m ²
/ g) 40% by weight, softwood bleached kraft pulp (freeness 5
50 ml), 40% by weight, core-sheath type heat-fusible polyester fiber (fiber diameter 14 μm, fiber length 5 mm, sheath portion melting point 110)
An air cleaning filter medium of Comparative Example 3 was produced in the same manner as in Example 1 except that the content of the fiber was 20% by weight.

[0049]

[Table 1]

Regarding the air cleaning filter media produced in the above Examples and Comparative Examples, pressure loss, particle collection efficiency, BET specific surface area of filter media B, benzene adsorption amount, filter media A
/ The interlayer strength of filter medium B was evaluated by the following method, and the results are shown in Table 2 below. [Pressure loss] Pressure loss of air cleaning filter media (m
mH ₂ O) has a surface wind speed of 5. in accordance with JIS B9908.
It was measured under the condition of 3 cm / sec. This value is 10mmH ₂ O
If it is the following, the air permeability is good.

[Particle Collection Efficiency] The particle collection efficiency (%) of the air cleaning filter material was measured in accordance with JIS B9908 under a surface wind velocity of 5.3 cm / sec. DOP aerosol (dioctyl phthalate, particle size 0.3 μm) was used as the particles to be measured, and a particle counter (KC-11) manufactured by Rion Co., Ltd. was used to measure the number of particles.

[BET Specific Surface Area] The BET specific surface area (m ² ) of the filter medium B is Accusorb 2100 manufactured by Shimadzu Corporation.
The amount of nitrogen adsorbed was measured using a -02 type, and the specific surface area calculated from the BET plot was converted into a value per 1 m ^{2 of} the filter material B and displayed.

[Benzene adsorption amount] The benzene adsorption amount (g / m ² ) of the filter medium B was measured according to JIS K1474, and converted into a value per 1 m ^{2 of} the filter medium B and displayed. When this value is 15 g / m ² or more, the deodorizing performance of the filter medium B is good.

[Interlayer Strength of Filter Material A / Filter Material B] The interlayer strength between the filter material A and the filter material B was examined by visually observing the condition between the layers when the air cleaning filter material was pleated. When no delamination was observed between the filter media, it was indicated by the symbol o, and when observed, it was indicated by the symbol x.

[0055]

[Table 2]

Evaluation: It is understood that the air cleaning filter media of Examples 1 to 10 have not only excellent dust-removing performance, but also sufficient deodorizing performance since the ultrafine glass fibers are effectively retained. In addition, the pressure loss is small, and not only does it have good air permeability, but delamination during pleating is not observed,
Excellent workability.

The air cleaning filter medium of Comparative Example 1 was
The filter medium A has the same configuration as the air cleaning filter medium of Examples 1 to 3 except that the filter medium A contains an organic fiber having a fiber diameter of more than 20 μm. However, in the air cleaning filter medium of Comparative Example 1,
It can be seen that the retention of the ultrafine glass fibers is inferior and the efficiency of collecting particles is greatly reduced when compared with the air cleaning filter media of Examples 1 to 3.

The air cleaning filter medium of Comparative Example 2 was
In the filter medium B, no binder fiber was used, and delamination of the filter medium A / filter medium B was observed during the pleating process, and it was found that the filter medium was inferior in processability.

The air cleaning filter medium of Comparative Example 3 was
It can be seen that the BET specific surface area per 1 m ^{2 of the} filter material B is less than 40,000 m ² , the adsorbed amount of benzene is small, and the deodorant performance is poor.

[0060]

The air cleaning filter medium of the present invention comprises:
An air cleaning filter medium having a two-layer structure in which a filter medium A having a dust removing performance and a filter medium B having a deodorizing performance are integrated.

In the filter medium A, the ultrafine glass fibers are well entangled with the organic fibers having a fiber diameter of 20 μm or less to form a uniform and dense network, and excellent dust removing performance is obtained even when the amount of the ultrafine glass fibers is small. Therefore, it is possible to obtain a filter medium excellent in dust removal performance without impairing air permeability.

On the other hand, in the filter medium B, the activated carbon fibers having a large adsorption rate and adsorption ability are effectively and firmly held by the natural fibers without blocking their micropores, and the activated carbon fibers are less likely to fall off. , And BE
Not only can a filter medium having a large T specific surface area and excellent in deodorizing performance be obtained, but the use of the natural fiber also strengthens the strain of the filter medium and improves processability.

Therefore, since the air cleaning filter medium of the present invention is excellent in both deodorizing performance and dust removing performance, and is also excellent in breathability and workability, it is processed into various structures such as honeycombs and folds, It can be used as an air cleaning filter medium in general rooms such as buildings and houses, automobiles, airplanes, etc.

Claims (4)

[Claims] 1. A filter medium A comprising ultrafine glass fibers, organic fibers having a fiber diameter of 20 μm or less, and binder fibers.
And active carbon fibers, is composed of natural fibers, and binder fibers, and a BET specific surface area per 1 m ² is two-layer structure with an integrated 40,000 m ² or more medium B, JI
An air cleaning filter medium having a pressure loss of 10 mmH ₂ O or less measured according to S B9908 at a surface wind velocity of 5.3 cm / sec. 2. The air cleaning filter medium according to claim 1, wherein the natural fiber is at least one selected from the group consisting of wood pulp, hemp pulp and cotton linter pulp. 3. The air cleaning filter medium according to claim 1 or 2, wherein the filter medium A or the filter medium B is a wet non-woven fabric. 4. A filter medium A produced by mixing an ultrafine glass fiber, an organic fiber having a fiber diameter of 20 μm or less, and a binder fiber into water to prepare an aqueous slurry, and making the aqueous slurry by the wet papermaking method, and activated carbon. A filter medium B prepared by mixing fibers, natural fibers, and binder fibers in water to prepare an aqueous slurry, and using the aqueous slurry to make a paper.
A method for producing an air cleaning filter medium, characterized in that and are combined together and dried.