JPH0592113A - Antibacterial air filter and its manufacture - Google Patents

Abstract

PURPOSE:To provide an antibacterial air filter with high safety and efficiency wherein antibacterial zeolite is stuck to a component fiber of the filter medium by easy process to provide stable antibacterial efficiency and the bacteria collected by the filter do not propagate and are not scattered again. CONSTITUTION:An antibacterial filter is prepared by coating a filter medium composed of glass fibers with 20mum or less fiber diameter with a solution of an antibacterial agent with several mum particle size by a spray nozzle 1. To the solution, an acryl-type binder is added to prevent antibacterial zeolite, etc., stuck to the fibers from scattering or peeling and thus enhancing the production yield. The antibacterial agent can be stuck to the filter by the easy treatment in this way and moreover high antibacterial efficiency is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air filter having an excellent antibacterial effect and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, in industries where a clean working environment is required, work is performed in a clean room where indoor air is cleaned. In such a clean room, outdoor air is filtered by a high-performance air filter such as a HEPA filter and supplied in a dust-free and nearly sterile state. But,
In laboratories such as foods, pharmaceuticals and brewing, manufacturing processes, hospitals, etc., in order to ensure product quality and hygiene, and to sterilize the human body, cleanliness in which microorganisms such as toxic molds and bacteria have been removed Need to be high. Therefore, it is required to completely collect the microorganisms on the high-performance air filter and to sterilize the air filter so that the collected microorganisms are not scattered again in the clean room.

As this sterilization treatment, there is conventionally known a filter in which a filter medium of a filter is made of synthetic fiber and an antibacterial agent such as zeolite particles is mixed in the fiber to obtain a sterilizing effect. In this case, as the antibacterial agent mixed in the filter, for example, the antibacterial zeolite disclosed in JP-A-63-265809 is used. Such an antibacterial agent such as antibacterial zeolite directly kneaded into the constituent fibers of the filter is known to have high antibacterial properties and is widely used as an antibacterial air filter.

[0004]

However, the antibacterial zeolite directly kneaded into the constituent fibers of the high-performance filter has the following problems.

That is, as the performance of the filter becomes higher, the fiber diameter of the filter medium becomes finer and it becomes more difficult to knead the antibacterial zeolite into the fiber of the filter medium. For example, in the HEPA filter, the skeleton material has a fiber diameter of 20 μm or less, and the filter material portion for collecting fine particles has a fiber diameter of about 1 μm. However, antibacterial agents generally have a minimum diameter of about 10 μm to about 0.5.
Used with a particle size of μm. Therefore, it is possible to knead the antibacterial agent into the skeletal material, but it is technically difficult to knead the antibacterial agent into the constituent fibers of the filter medium, which is important for collecting fine particles.

On the other hand, in the case of glass fiber generally used as a filter medium for high-performance filters, the processing temperature of the fiber is about 550.
Since the temperature is as high as ℃ or more, the antibacterial zeolite kneaded into the fiber is modified and the antibacterial effect cannot be obtained. For this reason, it becomes impossible to provide an air filter made of glass fiber in which antibacterial zeolite is kneaded.

The present invention has been proposed in order to solve the above-mentioned drawbacks of the prior art, and its purpose is to suppress the growth of microorganisms such as mold and bacteria in an air filter, and to sterilize it. It is an object of the present invention to provide an antibacterial air filter capable of maintaining the basic performance of the air filter as described above.

[0008]

In order to solve the above problems, the antibacterial air filter of the present invention has the following measures.

That is, the antibacterial air filter according to claim 1 of the present invention is characterized in that the particulate antibacterial agent is adhered to the surface of the fiber constituting the filter medium through the binder.

As fibers constituting the filter medium of such an antibacterial air filter, synthetic fibers such as polypropylene, polyamide and polyester, and fibers such as asbestos, cellulose, ceramic and glass are used. As the filter performance class, a high performance filter such as HEPA, an ultra high performance filter such as ULPA, or a medium performance filter is appropriately applied. For example, in the case of a high-performance filter, it is desirable that the fiber diameter be 20 μm or less, preferably about 1 μm.

On the other hand, as a particulate antibacterial agent, JP-A-63 is used.
The antibacterial zeolite disclosed in JP-A-265809, an antibacterial agent having a similar action, and the like are used. The shape of the antibacterial agent used in the present invention is preferably powder particles, and the particle diameter can be appropriately changed according to the type of filter. For example, in the case of a high performance filter, it is desirable that the thickness is 10 μm or less, preferably 5 to 0.5 μm. Further, the use state can be appropriately changed such as powder or one dispersed in a dispersion medium such as water. When dispersed in a dispersion medium, 0.
Used as a solution with a concentration of 005 to 50%. The amount of the antibacterial agent attached to the filter is 0.3 to 30 g / m.
² , preferably 3 to 5 g / m ² .

Further, after the antibacterial zeolite is attached to the surface of the filter fiber, a water-soluble polymer compound is used as a binder used to prevent scattering and peeling and to obtain a high yield. Acrylic compounds and vinyl acetate compounds can be used alone or in combination.

When the filter medium is dried, the drying temperature is adjusted by the kind of the binder, and the drying time is adjusted by the amount of the antibacterial agent or the binder attached.

By the way, as a method of attaching the antibacterial agent to the air filter, there is the following method.

First, there are a method of adhering an antibacterial agent to a paper-made filter material and a method of adding an aqueous solution of the antibacterial agent into the paper during the papermaking process of the filter material. In the former, the spray coating method,
There is a filtration attachment method. This filtration and attachment method includes a method of filtering an antibacterial agent aqueous solution and a method of filtering an antibacterial agent powder, both of which are attached by vacuum filtration or pressure filtration.

Here, in the spray coating method and the antibacterial agent aqueous solution filtration method, the antibacterial agent is attached in a state of being dispersed in a dispersion medium such as water so as to have an appropriate concentration. An appropriate concentration of a water-soluble binder is also dissolved in this dispersion medium.

On the other hand, in the antibacterial agent powder filtration method, air-dispersed particulate antibacterial agent powder is attached by filtration. In this case, the binder aqueous solution is sprayed after the adhesion.

The filter medium to which the antibacterial agent is attached as described above is formed as an antibacterial air filter by the following method. That is, after the filter medium to which the antibacterial agent is attached is dried in the drying step, it is subjected to a treatment such as being folded into pleats with a folding machine to form an antibacterial air filter. Alternatively, the antibacterial agent may be first applied to the pleated filter medium and dried to form the antibacterial agent.

An antibacterial air filter according to a second aspect of the present invention is characterized in that, in the antibacterial air filter according to the first aspect, the filter medium is made of glass fiber having a fiber diameter of 20 μm or less.

The antibacterial air filter according to a third aspect of the present invention is the antibacterial air filter according to the first aspect, in which a particulate antibacterial agent is attached to the surface of the filter medium on the side of collecting fine particles and the inside of the side of collecting the particles. It is characterized by Such a filter can be obtained by adhering the antibacterial agent only to the collecting side of the filter medium by spraying, or by stacking a filter in which the antibacterial agent is adhered to the entire fiber and a non-added filter.

The method for producing an antibacterial air filter according to claim 4 of the present invention is the antibacterial air filter according to claim 3, wherein a binder is mixed on the surface of the filter medium on the side of collecting fine particles and on the inside of the side of collecting. The particulate antibacterial agent solution is applied by spraying.

[0022]

The operation of the present invention having the above construction is as follows.

That is, in the antibacterial air filter according to claim 1 of the present invention, when microorganisms are collected by the filter,
It is sterilized by the particulate antibacterial agent fixed to the fiber surface of the air filter with a binder. Therefore, to prevent the growth of microorganisms, because further sterilization is performed,
It is possible to prevent re-scattering of microorganisms and provide an antibacterial air filter having a high cleaning effect.

Further, in the antibacterial air filter according to the second aspect, it is difficult to knead the antibacterial agent with glass fiber which has been impossible to have an antibacterial property by being heated at a high temperature when forming the filter medium. For fiber diameters less than 1 μm,
A high antibacterial effect can be obtained by attaching the antibacterial agent.

Furthermore, in the antibacterial air filter according to the third aspect, since the particulate antibacterial agent adheres to the surface of the filter on the dust collecting side and the inside of the collecting side, the particulate antibacterial agent is provided on the clean air discharge side. There will be no agent adhesion. Therefore, even if the particulate antibacterial agent is separated from the filter, it does not scatter into the purified air. Therefore, it is possible to provide an air filter having high antibacterial properties in which purified air is not contaminated by microorganisms or antibacterial agents.

On the other hand, in the method for producing an antibacterial air filter according to the fourth aspect of the present invention, the antibacterial agent is sprayed to be uniformly dispersed and adhered to the surface of the filter on the dust collecting side and the inside of the collecting side. Therefore, an air filter having high antibacterial properties can be manufactured by an easy means.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

(1) First Example The filter medium of the antibacterial air filter of this example has a fiber diameter of 20.
It is composed of glass fibers of not more than μm and is formed by papermaking. This filter medium is formed into a size of 250 mm × 300 mm having an effective filter medium area of 0.075 m ^2, and the antibacterial agent solution is uniformly applied using the spray nozzle 1 as shown in FIG. At this time, two types of spray nozzles are prepared, one having a small spray diameter and the other having a coarse spray diameter. Further, as an antibacterial agent used for this, the above-mentioned JP-A-63-265809 is used.
The antibacterial zeolite shown in No. 1 is used. The particle size of this antibacterial zeolite is 2.0 μm. Further, as the antibacterial agent solution, a solution having antibacterial agent concentrations of 5% and 10% is prepared.
The acrylic binder in these solutions is adjusted to have a concentration of 2%. This antibacterial agent solution is sprayed so that the amount of adhesion to the filter is about 2.4 to 5.9 g / m ² . The filter coated with this antibacterial agent
Drying is carried out at a drying temperature of 110 ° C. for 60 minutes using a forced convection dryer.

An electron micrograph of the fiber surface of the antibacterial air filter of this example formed as described above is shown in FIG.
And shown in FIG. Here, FIG. 3 shows the one to which the antibacterial agent was attached by the spray method of the fine spray diameter, and FIG. 4 shows the one to which the antibacterial agent was attached by the spray method of the coarse spray diameter. The electron micrograph at this time is a magnification: × 200, scale: 2
The image was taken under the condition of cm × 100 μm.

On the other hand, as an example of this embodiment, Table 1 shows the amount of antibacterial agent deposited and the results of its antibacterial property test.

[0031]

[Table 1] Here, the antibacterial test was performed as follows in order to evaluate the antibacterial effect of the antibacterial air filter. As a bacterium, Staphylococcus aureu
s) and E. coli (Escherichia coli)
Was used. The test method was as follows: 1 ml of each bacterial solution (10 ⁵ cells / ml) was dropped on both sides of a sample (50 × 50 mm),
Incubate at 37 ° C for 18 hours. Then, the bacteria are washed out with a sterilized phosphate buffer solution. The viable cell count of the washed-out liquid is measured by the pour plate method using a culture medium for measuring the cell count and evaluated.

(2) Second Example A filter medium formed in the same manner as in the first example is formed in a size of 200 mm × 250 mm having an effective filter medium area of 0.05 m ² . This filter medium is placed on the Goochl crucible 2 as shown in FIG. 2, and the antibacterial agent solution is filtered and uniformly attached. The Goochl crucible 2 is connected to a vacuum pump 3 and the solution is filtered under reduced pressure. The filtration speed at this time is regulated by the decompression force,
This is regulated by the pressure regulating valve 4. On the other hand, the same antibacterial agent as in the first embodiment is used, and an antibacterial agent solution having a concentration of 0.05% is prepared. This solution is adjusted so that the acrylic binder has a concentration of 2%. The amount of the antibacterial agent deposited on the filter was 2.4 to 5.0 g / m ²
It adheres so that it becomes the application amount.

An electron micrograph of the fiber surface of the antibacterial air filter of the present embodiment formed as described above is shown in FIG.
Shown in. The shooting conditions are the same as in the first embodiment described above. In addition, the amount of the antibacterial agent deposited and the result of the antibacterial property test of this example are shown in Table 1 above.

From the results shown in the above examples, it is confirmed that antibacterial zeolite is sufficiently adhered to the surface of the constituent fibers of the filter medium, and that the antibacterial zeolite is
It can be seen that sufficient antibacterial properties are exhibited. Therefore, a high antibacterial effect can be obtained by using a small amount of antibacterial zeolite as compared with the conventional kneading. Therefore, it is possible to provide an inexpensive antibacterial air filter having a high antibacterial effect.

Particularly, in the manufacturing method in which the antibacterial zeolite is attached to the filter by the spray method, the particulate antibacterial agent can be easily dispersed and evenly adhered to both the fine spray particles and the coarse spray particles. Moreover, since the antibacterial agent adheres to the dust collecting side surface and the inside of the collecting side, the antibacterial agent does not adhere to the clean air exhaust side. Therefore, even if the particulate antibacterial agent is peeled off from the filter, it is not mixed and scattered in the purified air. Therefore, it is possible to manufacture an air filter having a high antibacterial property and an excellent cleaning action by a simple means.

[0036]

According to the present invention as set forth in claim 1, the antibacterial agent is attached to the filter medium through the binder, so that the microorganisms such as bacteria and mold trapped in the filter can be stably propagated for a long period of time. It can be suppressed to a minimum and can be sterilized. Therefore, it is possible to provide an antibacterial air filter having high safety and high performance, in which the microorganisms collected by the filter are not re-scattered.

Further, according to the present invention as set forth in claim 2, since the antibacterial agent is attached to the surface of the filter medium, the antibacterial agent can be kneaded with the glass fiber which has not been able to have the antibacterial property. It is possible to obtain a filter having a high antibacterial property even with a fiber diameter of 1 μm or less, which has been difficult.

Further, according to the invention of claim 3,
The particulate antibacterial agent adheres to the surface of the filter on the dust collecting side and to the inside of the collecting side, that is, the particulate antibacterial agent does not adhere to the clean air discharge side, so the antibacterial agent peeled from the filter. Can be prevented from scattering in the purified air. Therefore, it is possible to provide an air filter that can stably exhibit a high degree of cleanliness.

On the other hand, according to the present invention of claim 4, since the antibacterial agent is attached to the surface of the filter on the dust collecting side and the inside of the collecting side by the spray method, an air filter having a high antibacterial property can be easily obtained. It can be manufactured by any means.
Especially in the case of the spray method, the antibacterial agent solution penetrates from the dust collecting side surface of the filter to the inside, so the antibacterial effect spreads to the clean air discharge side which is the back side, and the antibacterial effect of the entire filter is maintained. be able to. Moreover, since the antibacterial agent itself is not attached to the cleaning air discharge side, the antibacterial agent particles are not mixed and scattered in the discharged clean air. Therefore, an air filter capable of exhibiting a high degree of cleanliness can be manufactured by easy means.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a processing step of a first embodiment of an antibacterial air filter of the present invention.

FIG. 2 is an explanatory view showing a processing process of a second embodiment.

FIG. 3 is an electron micrograph showing a fiber surface of an antibacterial air filter to which an antibacterial agent is attached by a spray method with a small spray diameter.

FIG. 4 is an electron micrograph showing a fiber surface of an antibacterial air filter to which an antibacterial agent is attached by a spray method with a coarse spray diameter.

FIG. 5 is an electron micrograph showing a fiber surface of an antibacterial air filter to which an antibacterial agent is attached by a filtration method.

[Explanation of symbols]

 1 Spray Nozzle 2 Goocht crucible 3 Vacuum pump 4 Pressure adjustment valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuhiko Nakano 2-7-3 Tenma, Kita-ku, Osaka City, Osaka Prefecture Techno Techno Ryowa Osaka Branch Office (72) Inventor Yasuo Kurihara Toyooka, Mizuho-ku, Nagoya, Aichi Prefecture 3rd Street, 35th Street (72) Inventor Naruaki Mitsusaki 1-37 Kyoritsutsumi, Hiratsuka-shi, Kanagawa Japan Air Filter Co., Ltd. (72) Inventor Masayuki Okamoto 1-37, Kyuretsumi, Hiratsuka-shi, Kanagawa Japan Inside Air Filter Co., Ltd.

Claims (4)

[Claims] 1. An antibacterial air filter characterized in that a particulate antibacterial agent is adhered to the surface of fibers constituting a filter medium through a binder. 2. The antibacterial air filter according to claim 1, wherein the filter medium is made of glass fiber having a fiber diameter of 20 μm or less. 3. The antibacterial air filter according to claim 1, wherein a particulate antibacterial agent is attached to the surface of the filter medium on the side of collecting fine particles and the inside of the side of collecting the particles. 4. The antibacterial air filter according to claim 3, wherein a particulate antibacterial agent mixed with a binder is applied to the surface of the filter medium on the side of collecting fine particles and the inside of the side of collecting by a spray. Production method.