JP2000210534A - Photocatalytic deodorizing filter - Google Patents

Abstract

(57) Abstract: A photocatalytic deodorizing filter characterized in that at least a photocatalyst and an adsorbent are supported on a three-dimensional network structure protected by an inorganic binder, with low pressure loss and efficient various odors. An object of the present invention is to provide a photocatalytic deodorizing filter characterized by having a long life by being decomposed and removed by a photodecomposition action upon contact with a component. Aldehydes generated by the decomposition of harmful substances by the photodegradation of photocatalysts,
By adsorbing and removing odor components such as formaldehyde released into the living environment such as new building materials, deactivation of the adsorbent,
An object of the present invention is to provide a photocatalytic deodorizing filter that does not generate an off-flavor due to emission of aldehydes and does not impair health. A photocatalytic deodorizing filter characterized in that at least a photocatalyst and an adsorbent are supported on a three-dimensional network structure protected by an inorganic binder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deodorizing filter using at least a photocatalyst and an adsorbent. More specifically, the present invention relates to a three-dimensional network structure in which a substrate is protected by an inorganic binder. The present invention relates to a photocatalytic deodorizing filter which is decomposed and removed by contact with various odor components.

[0002]

2. Description of the Related Art Conventionally, odors caused by industrial odors in factories and the like, and odors caused by wastes in service industries such as restaurants and hotels that discharge a large amount of waste have been problems. In addition, odors in daily living spaces such as in automobiles and in general rooms have also been highlighted. Therefore, there is an increasing need for the removal of harmful substances such as odors, and air purifiers and air conditioners incorporating a odor removal device, a odor removal filter, and the like are being actively developed.

[0003] In general air purifiers and air conditioners, a filter containing activated carbon is used, and a method of adsorbing harmful substances such as odors to the activated carbon is employed. However, activated carbon only exhibits an adsorption effect on most harmful substances, and when a certain amount of harmful substances is adsorbed, the filter must be replaced. Alternatively, there is a problem that the harmful substance once adsorbed is easily released due to a rise in ambient temperature or a decrease in the concentration of the harmful substance.

As described in Japanese Patent Application Laid-Open No. 8-155240, a small-sized, low-pressure-loss filter in which activated carbon impregnated is supported on a plastic foam or the like has been proposed. The short is the problem.

In recent years, in order to solve such a problem,
Materials using a catalyst capable of decomposing harmful substances or materials combining the catalyst with an adsorbent such as activated carbon have been developed. For example, Japanese Patent Application Laid-Open No. 1-234729 discloses an air purifier incorporating a deodorant obtained by forming a layer of titanium dioxide having photocatalytic ability on the surface of honeycomb activated carbon. The air purifier is equipped with an ultraviolet lamp, and irradiates the deodorant with ultraviolet light to decompose and remove harmful substances adsorbed on activated carbon by the photocatalytic action of titanium dioxide.

In addition, JP-A-2-253848 discloses that an anatase type titanium oxide is used as an inorganic fibrous carrier.
Activated carbon, and an ozonolysis catalyst supporting components having ozonolytic properties such as manganese, iron, copper, cobalt, and nickel have been proposed, but since the carrier is fibrous, an adsorbent or the like must be used for direct use as a filter. Since the surface area that can be supported is too small, there is a problem in using it as a deodorizing filter.

Japanese Unexamined Patent Publication (Kokai) No. 4-256755 discloses a material capable of decomposing and removing various harmful substances such as a photocatalyst removing material made of granular pulp carrying a photocatalyst such as titanium dioxide.

[0008] Above all, a deodorizing filter using a photocatalyst used for an air purifier, an air conditioner or the like usually deodorizes by increasing the contact area with the odor in the form of a honeycomb or corrugate. In the case where the honeycomb or corrugate is formed of a metal such as aluminum, a method of supporting a desired photocatalyst by a one-by-one or one-dip method after forming the honeycomb or corrugate is usually employed, so that the manufacturing cost is reduced. Costly is a problem.

[0009] Further, a sheet in which a photocatalyst is embedded in a nonwoven fabric or the like is processed into a honeycomb or corrugated shape. This method also has a problem in that an adhesive is used at the time of processing the honeycomb or corrugate, and this portion is decomposed by the photocatalyst and the shape of the honeycomb or corrugate cannot be maintained.

By using a material using a catalyst capable of decomposing harmful substances or a material in which a photocatalyst is combined with an adsorbent such as activated carbon, a more effective method can be used as compared with a case where the adsorbent is used alone. Deodorization becomes possible. However,
In these prior arts, no consideration is given to various aldehydes generated by decomposition of harmful substances. For example, aldehydes, which are one of the representative malodorous substances, are generated by the photocatalytic decomposition of alcohols, and it is generally known that aldehydes are less healthy than alcohols.

Further, in a general residential environment, the so-called sick building syndrome, which causes a formaldehyde component contained in an adhesive to be released into a room and causes a respiratory disease and a skin disease, particularly when a new building material is used, is a social problem. Has become. It has also been pointed out that acetaldehyde, which is a main component of tobacco, is harmful to health.However, ordinary activated carbon cannot remove aldehydes efficiently, and even if an adsorbent with excellent aldehyde adsorption capacity is used, However, if the aldehyde is saturated, no further aldehyde removal effect can be expected, and if the surrounding aldehyde concentration is low, the adsorbed aldehyde is released. These aldehydes are not easily adsorbed by activated carbon, and may be eventually decomposed into water and carbon dioxide if they are effectively photodegraded.However, when activated carbon is adsorbed and saturated, it does not reach adsorption saturation. When the ambient temperature rises, it is also radiated to the outside, which may cause off-flavors and contamination of surrounding materials.

As activated carbon for adsorbing aldehydes, impregnated activated carbon and the like are known. Since these impregnated activated carbons impregnate harmful chemical substances such as aniline that react with aldehydes, these chemical substances are released into the atmosphere by volatilization or dissolution at high temperatures or high humidity, and the like. It is a potentially harmful substance and may cause air pollution.

Further, as disclosed in Japanese Patent Application Laid-Open No. 9-249824, an air purifying paint composed of a photocatalyst, high silica zeolite and an organic binder, and an air-purifying paint coated with them, are decomposed and formed by the photocatalytic action. There is a possibility that an object may be generated, and there is a possibility that the air is contaminated. Further, there is a concern that the coating film produced by such a coating material may be loosely peeled off due to photocatalysis and fall off.

[0014]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a low pressure loss, efficiently comes in contact with various odor components, and is decomposed and removed by a photodecomposition action, thereby achieving a long life. An object of the present invention is to provide a photocatalytic deodorizing filter characterized by the following. Adsorbents such as aldehydes generated by the decomposition of harmful substances by photocatalytic action of photocatalysts and odor components such as formaldehyde released to the living environment such as new building materials are absorbed and deactivated, and aldehydes are released. An object of the present invention is to provide a photocatalytic deodorizing filter that does not generate an off-flavor and does not impair health.

[0015]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have come to invent a photocatalytic deodorizing filter.

That is, a photocatalyst deodorizing filter characterized in that at least a photocatalyst and an adsorbent are supported on a three-dimensional network structure protected by an inorganic binder.

(2) The number of cells of the three-dimensional network structure is six.
The photocatalyst deodorizing filter according to claim 1, wherein the size is from 35 to 25/25 mm.

3. The photocatalytic deodorizing filter according to claim 1, wherein the three-dimensional network structure is a plastic foam.

(4) The photocatalytic deodorizing filter according to (1), (2) or (3), wherein the adsorbent is a high silica zeolite.

Hereinafter, the present invention will be described in detail.

By supporting at least the photocatalyst and the adsorbent on a three-dimensional network structure protected by an inorganic binder, a photocatalytic deodorizing filter can be manufactured. Usually, a photocatalyst deodorizing filter used in an air purifier or an air conditioner needs to process a sheet or the like carrying a photocatalyst into a honeycomb or corrugated shape. A photocatalyst deodorizing filter can be easily obtained by supporting and cutting a photocatalyst and an adsorbent on a plastic foam having a certain thickness.

When a photocatalyst is directly supported on a three-dimensional network structure with an organic binder or the like, the photodecomposition action causes
The organic three-dimensional network structure and the organic binder serving as the base material are violated. Therefore, after protecting the three-dimensional network structure using an inorganic binder, a photocatalyst is further supported using the inorganic binder.

Conventional honeycombs and corrugates use glue in the process of processing, and the glue is decomposed by the photocatalyst, making it impossible to maintain its shape. Is not used, so that the shape does not collapse due to the photolytic action.

In the present invention, by further containing an adsorbent, deodorization can be performed more effectively. The decomposition effect of the photocatalyst is poor only on the surface of the photocatalyst because the reaction occurs, and the deodorizing property is insufficient even for a high-concentration odor.
Therefore, when used in combination with the adsorbent, the odor component is first captured by the adsorbent, and is gradually decomposed and completely deodorized by the photocatalyst in the vicinity.

In the present invention, the photocatalytic deodorizing filter is characterized in that the number of cells of the three-dimensional network structure of the substrate is 6 to 35 cells / 25 mm.
Even if the thickness is small, a filter having good air permeability can be obtained while maintaining the shape.

In the present invention, a photocatalyst deodorizing filter characterized by supporting at least a photocatalyst and an adsorbent on a plastic foam is rich in flexibility, excellent in processability, and has a certain thickness, so that the photocatalyst can be used. The UV light to be activated can be used effectively. That is, as a light source used in a normal photocatalytic air purifier, there is an elongated cylindrical black lamp or a cold cathode tube, and the filter is installed so as to be wrapped therearound, so that the light source can be used without waste. The photocatalytic ability can be fully utilized.

Further, when the adsorbent in the present invention is a high silica zeolite, deodorization of aldehydes can be effectively performed. Hereinafter, the high silica zeolite will be described in detail.

Ordinary zeolite is chemically a crystal of an aluminosilicate metal salt, and its uniform pore structure and the electrostatic field generated by ions strongly polarize polar molecules smaller than the pores, such as water, alcohol, and carbon dioxide. It has the property of adsorbing. Therefore, when ordinary zeolite is used as the adsorbent, water in the air atmosphere is preferentially adsorbed, and pores are closed before absorbing odor components.

The high silica zeolite in the present invention is chemically a crystal of an aluminosilicate metal salt, similarly to a normal zeolite. However, the ratio of silica to alumina in the crystal is different from that of ordinary zeolite, and the ratio of silica is larger than that of alumina. Also,
Since the oxygen atoms in the silica structure have little basicity and do not participate in the formation of hydrogen bonds, the Si atoms on the zeolite surface
The —O—Si bond exhibits water repellency and does not adsorb water molecules.
Therefore, as the ratio of silica to alumina increases, the water repellency increases.

The high silica zeolite according to the present invention hardly adsorbs water molecules, so that the performance under high humidity hardly decreases. Biological odors such as putrefaction odor and sweat odor often occur in a high-temperature and high-humidity environment. Therefore, deodorizing performance under high humidity becomes very important. Moreover, even at high temperatures, since it is tightly confined within the crystal lattice, the adsorption performance of the high silica zeolite hardly decreases.

The high silica zeolite of the present invention can adsorb a wide range of odor components. For example, various odor components such as organic acids, ammonia, acetaldehydes, ketones, amines, sulfur compounds, and indoles can be adsorbed. The adsorption mechanism of high silica zeolite depends on the size of the pores and the static electricity of the cation corresponding to the number of aluminum atoms in the framework of the zeolite crystal. Therefore, by changing the ratio of silica, even non-polar molecules can be adsorbed, unlike ordinary zeolites.

The deodorizing sheet of the present invention decomposes and removes harmful substances by the photoresolving power of the photocatalyst. However, aldehydes may be generated as decomposition intermediates from alcohols and the like by the decomposing action of the photocatalyst. is there.

These aldehydes are typical malodorous substances or compounds that impair health, so it is preferable that they can be effectively removed from the living environment. However, there is no adsorbent that can be adsorbed effectively, There were problems such as release of adsorbed molecules when saturated.

However, by using at least the photocatalyst and the high silica zeolite in combination, it is possible to remove, for example, various aldehydes adsorbed by the high silica zeolite, aldehydes in the atmosphere, aldehydes generated by the photolysis reaction, and various odor components. .

The high silica zeolite in the present invention is:
The odor is not absorbed or decomposed by a chemical reaction, but is simply absorbed and removed. Therefore, it is very compatible with a photocatalyst. That is, the odor component adsorbed by the high silica zeolite can be completely deodorized by oxidative decomposition under the appropriate ultraviolet light by the photocatalytic action of the photocatalyst.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention provides a photocatalytic deodorizing filter characterized in that at least a photocatalyst and an adsorbent are carried on a three-dimensional network structure protected by an inorganic binder. In addition, aldehydes generated by the decomposition of harmful substances due to the photolytic action of the photocatalyst and odor components such as aldehydes released to the living environment such as new building materials are absorbed and removed, thereby deactivating the adsorbent and dispersing the aldehydes. Provided is a photocatalyst deodorizing filter which does not cause off-flavors or impair health.

In the present invention, the photocatalyst used in the deodorizing filter containing at least the photocatalyst and the adsorbent includes:
A semiconductor which has a photocatalytic reaction having a band gap of 0.5 to 5 eV, preferably 1 to 3 eV, in which harmful substances are decomposed by OH radicals generated by photoexcitation. The shape of the photocatalyst is preferably in the form of particles, and particles having a specific surface area of 10 to 500 m ² / g are appropriately selected and used.

As such a photocatalyst, Japanese Patent Application Laid-Open No. 2-2
No. 73514 can be cited, and metal oxides such as zinc oxide, tungsten trioxide, titanium oxide, and cerium oxide are preferable. Among these, titanium oxide has structural stability and photocatalyst. It is a particularly preferable material in consideration of its ability as a material, safety in handling, and the like. As titanium oxide, in addition to titanium dioxide, hydrous titanium oxide, hydrated titanium oxide, metatitanic acid, orthotitanic acid, titanium hydroxide and the like can be used, and the crystal form is not particularly limited.
When using titanium oxide, its specific surface area is 50 to 4
A thing of 00 m ² / g is preferred. Further, the surface of titanium oxide may be coated with a metal such as platinum, gold, silver, palladium, rhodium and ruthenium, or a metal oxide such as ruthenium oxide and nickel oxide.

In the present invention, various adsorbents can be used in combination with the photocatalyst. For example, activated carbon, impregnated activated carbon, coconut shell activated carbon, manganese dioxide such as zeolite,
Examples include catalytic metal oxides such as iron dioxide, and noble metal catalytic adsorbents such as platinum and platinum, and mixtures thereof. Above all, a physical adsorption type adsorbent is preferably used. The shape of these adsorbents is not particularly limited, but in consideration of the photocatalyst, particularly when used in combination with anatase-type powdered titanium dioxide, particles are preferable.
It is preferable to select and use one having a specific surface area of 50 to 2000 m ² / g as appropriate. For example, in the case of activated carbon, 5
It is preferably from 1,000 to 1500 m ² / g.

In the present invention, when a photocatalyst and an adsorbent are mixed and supported on the three-dimensional network structure, when the three-dimensional network structure is a plastic foam or the like, there is a possibility that the three-dimensional network structure will be attacked by a photolytic action. . Therefore, it is necessary to protect the three-dimensional network structure by some method. As the method, it is preferable to coat the three-dimensional network structure with an inorganic binder and then support the photocatalyst. Preferred examples of the inorganic binder include a clay-based binder and alumina sol.

In the present invention, various methods can be used as means for coating and protecting the three-dimensional network structure with an inorganic binder. It can be produced by preparing a solution of an inorganic binder, dipping the solution into a three-dimensional network structure, and then drying. In addition, it can be produced by various methods such as a size press method, an air knife method, and an impregnation coating method. At this time, care should be taken so that the cell is not coated with a binder film.

In the present invention, the optimal amounts of the photocatalyst and the adsorbent vary depending on the thickness of the three-dimensional network structure used, the number of cells, the required pressure loss, and the like. In the case of an adsorbent, the amount is preferably 0.01 to 0.05 g per CC. The photocatalyst is preferably 0.001 to 0.006 g per CC.

In the present invention, when the photocatalyst and the adsorbent are separately supported, it is preferable that the adsorbent is first supported on the plastic foam, and then the photocatalyst is supported thereon. If formed on the contrary, the photocatalytic activity will be reduced.

In the present invention, when an inorganic adsorbent is first supported on the three-dimensional network structure, a protective layer using an inorganic binder is not required. That is, the inorganic adsorbent substitutes for the inorganic binder. In this case, an inorganic adsorbent may be supported on the three-dimensional network structure using an organic binder. Since an inorganic adsorbent powder having a very large surface area is used, even if a photocatalyst layer is provided on the adsorbent, the organic binder hardly comes into contact with the photocatalyst and there is no fear of deterioration. The photocatalyst layer is formed on the adsorption layer by using a clay-based binder or alumina sol as a binder. The amount of the organic binder used is preferably 10 to 50% by weight with respect to the inorganic adsorbent.

When the number of cells is used as an index indicating the air permeability of the three-dimensional network structure used in the present invention, 6
Structures with ~ 35 cells / 25 mm are preferred. When the number of cells is smaller than 6/25 mm, the structure cannot be maintained alone when the thickness is thinly sliced for a filter. On the other hand, when the number of cells is larger than 35 cells / 25 mm, the air permeability deteriorates, and even if sliced thinly, it cannot be used as a filter. Therefore, the number of cells depends on the pressure loss to be obtained depending on the device to be incorporated.
Pieces / 25 mm is more preferred.

In the present invention, various materials can be used as the material of the three-dimensional network structure. Nickel and plastic are preferred. Among them, a plastic foam or the like is particularly preferably used from the viewpoint of processability and flexibility.

The types of plastic foam preferably used in the present invention include the following. Polystyrene foam, polyethylene foam, polyurethane foam, polypropylene foam, vinyl chloride foam, rubber foam, EVA foam, ABS
Foam, polyamide foam, acrylic foam, phenol foam, urea foam, silicone foam, epoxy foam and the like. Among them, urethane foam is more preferable from the viewpoints of water resistance, aging resistance, resistance to chemical substances and various solvents. As for the urethane foam, any of a soft product, a semi-hard product, and a hard product can be used. Further, both ether-based and ester-based can be preferably used.

The plastic foam used in the present invention may be of any thickness. Although there is a relationship with the pressure loss, a material having a thickness of 1 to 20 mm can be preferably used. Further, it is more preferable that the number of
A thickness of 15 mm is good.

In the present invention, when a photocatalyst and an adsorbent are carried on a plastic foam protected with an inorganic binder, if the binder is immobilized using a usual organic binder, the binder is attacked. Therefore, similarly to the protection of the plastic foam, a clay-based binder or an alumina sol is preferably used. The amount used is 2 per photocatalyst.
0-100% by weight is preferred.

In the present invention, when the adsorbent is a high silica zeolite, it can be treated in the same manner as the adsorbent described above. Various adsorbents may be used in combination.

[0051]

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

Example 1 1 part by weight of a clay binder (Kunipia, manufactured by Kunimine Chemical Industry Co., Ltd.) was dissolved in 99 parts by weight of water to prepare a 1% by weight coating solution. This coating liquid is 13 cells / 25 mm, 5 mm
Thick urethane foam (Kurashiki Spinning Co., Ltd., ester foam) was impregnated and coated to obtain a urethane foam protected by an inorganic binder having a coating amount of 2 g / m ² . Next, as a photocatalyst, titanium dioxide powder (produced by Nippon Aerosil Co., Ltd., P25S
6) Disperse 15 parts by weight of zeolite (Mizukanite AP manufactured by Mizusawa Chemical Co., Ltd.) and 300 parts by weight of water. Next, 625 parts by weight of a 4% aqueous clay binder solution as an inorganic binder was added and stirred to obtain a coating solution having a solid content concentration of 10% by weight, which was used as a photocatalyst coating solution. The urethane foam previously impregnated and coated with this coating liquid is impregnated and coated, and a coating amount of 1
Example 1 A photocatalytic deodorizing filter of 00 g / m ² was prepared and used as Example 1.

Example 2 Titanium dioxide powder (produced by Nippon Aerosil Co., Ltd.)
P25S6) 15 parts by weight and 60 parts by weight of powdered activated carbon (Kuraray Chemical Co., Ltd., Kuraray Coal) are dispersed in 300 parts by weight of water. Next, 625 parts by weight of a 4% strength aqueous clay binder solution as an inorganic binder was added and stirred to obtain a solid content of 1%.
A coating solution of 0% by weight was obtained. This coating solution was impregnated and applied to urethane foam precoated with only a clay binder in Example 1 to prepare a photocatalytic deodorizing filter having a coating amount of 100 g / m ² , and Example 2 was obtained.

Example 3 Titanium dioxide powder (produced by Nippon Aerosil Co., Ltd.)
300 parts by weight of water are dispersed with 15 parts by weight of P25S6, 30 parts by weight of high silica zeolite (HSZ-690HOA, manufactured by Tosoh Corporation), and 30 parts by weight of zeolite (Mizukanite AP, manufactured by Mizusawa Chemical Co., Ltd.). Next, 625 parts by weight of a 4% aqueous clay binder solution as an inorganic binder was added and stirred to obtain a coating liquid having a solid content of 10% by weight. A photocatalyst coating liquid was used. This coating liquid was impregnated and applied to urethane foam precoated with only a clay binder in Example 1 to prepare a photocatalytic deodorizing filter having a coating amount of 100 g / m ² , to obtain Example 3.

Example 4 One part by weight of a clay binder (Kunipia, manufactured by Kunimine Chemical Industry Co., Ltd.) was dissolved in 99 parts by weight of water to prepare a 1% by weight coating solution. This coating liquid was used for 5 cells of 20 cells / 25 mm.
Thick urethane foam (Kurashiki Spinning Co., Ltd., ester foam) was impregnated and coated to obtain a urethane foam protected by an inorganic binder having a coating amount of 2 g / m ² . Next, the photocatalyst coating liquid of Example 3 was impregnated and applied to the urethane foam previously coated to prepare a photocatalyst deodorizing filter having a coating amount of 100 g / m ² , to obtain Example 4.

Example 5 One part by weight of a clay binder (Kunipia, manufactured by Kunimine Chemical Industry Co., Ltd.) was dissolved in 99 parts by weight of water to prepare a 1% by weight coating solution. This coating liquid is 13 cells / 25 mm, 5 mm
Thick polyethylene foam (manufactured by Inoac Corporation, PE Lite) is impregnated and coated at a coating amount of 2 g /
A polyethylene foam protected by m ² inorganic binder was obtained. Next, the photocatalyst coating liquid of Example 3 was impregnated onto the previously coated polyethylene foam, and the coating amount was 100 g.
Example 5 was prepared by preparing a photocatalyst deodorizing filter having a density of / m ² .

Comparative Example 1 Titanium dioxide powder (produced by Nippon Aerosil Co., Ltd.)
P25S6) 15 parts by weight, zeolite (manufactured by Mizusawa Chemical Co., Ltd.)
60 parts by weight of Mizucanite AP) and 300 parts by weight of water are dispersed. Next, 625 parts by weight of a 4% aqueous clay binder solution as an inorganic binder was added and stirred to obtain a solid content of 10%.
% By weight of the coating liquid was obtained as a coating liquid for the photocatalyst. This coating solution was impregnated and coated on a urethane foam (ester foam, manufactured by Kurashiki Spinning Co., Ltd.) having 13 cells / 25 mm to prepare a photocatalytic deodorizing filter having a coating amount of 100 g / m ^2. did.

Comparative Example 2 Titanium dioxide powder (produced by Nippon Aerosil Co., Ltd.)
P25S6) Disperse 75 parts by weight of 300 parts by weight of water.
Next, 625 parts by weight of a 4% aqueous clay binder solution as an inorganic binder was added and stirred to obtain a coating solution having a solid content concentration of 10% by weight, which was used as a photocatalyst coating solution. This coating solution was impregnated with a 13-cell / 25 mm urethane foam (Kurashiki Spinning Co., Ltd., Ester Foam) to obtain a coating amount of 1
A photocatalyst deodorizing filter of 00 g / m ² was prepared to be Comparative Example 2.

Comparative Example 3 Zeolite (Mizukanite AP, manufactured by Mizusawa Chemical Co., Ltd.) 180
Parts by weight are dispersed in 777.5 parts by weight of water. Styrene / acrylic emulsion binder 47% concentration (Japan NSC
(42.5 parts by weight) was added to obtain a coating liquid. This coating solution was impregnated with a 13-cell / 25 mm urethane foam having a thickness of 5 mm (Ester Foam, manufactured by Kurashiki Spinning Co., Ltd.) to prepare a deodorizing filter having a coating amount of 100 g / m ² . .

Comparative Example 4 Titanium dioxide powder (produced by Nippon Aerosil Co., Ltd.)
P25S6) 15 parts by weight, zeolite (manufactured by Mizusawa Chemical Co., Ltd.)
60 parts by weight of Mizucanite AP) and 300 parts by weight of water are dispersed. Next, 625 parts by weight of a 4% aqueous clay binder solution as an inorganic binder was added and stirred to obtain a solid content of 10%.
% By weight of the coating liquid was obtained as a coating liquid for the photocatalyst. This coating solution was applied to a nonwoven fabric made of polyethylene terephthalate fiber produced by a wet method to prepare a photocatalytic deodorizing sheet having a coating amount of 50 g / m ² . Using this sheet and an adhesive of ethylene-vinyl acetate type, 300 × 273 ×
It was processed into a corrugate having a size of 5 mm, a pitch of 4.1 mm, and a height of 2.65 mm to prepare a deodorizing filter, which was used as Comparative Example 4.

<Installation of Dust Removing and Deodorizing Filter on Equipment> The photocatalytic deodorizing filters and deodorizing filters of Examples 1 to 5 and Comparative Examples 1 to 4 were cut into a size of 300 × 273 × 5 mm. The filter of this size was installed on the pre-filter installation part by removing the photocatalyst filter of a new wind fan (photocatalyst type air purifier manufactured by Mitsubishi Paper Mills, Ltd.).
The size of the photocatalyst deodorizing filters produced in the examples and comparative examples fits perfectly in the housing frame of the new and fresh air blower. Also,
Since the current new and fresh air blowers have a distance from the UV lamp installation section to the pre-filter section, two UV lamps were installed immediately downstream of the installed filter.

<Evaluation of Comprehensive Deodorizing Performance> Using a new and fresh air blower incorporating the photocatalyst deodorizing filters and deodorizing filters of Examples 1 to 5 and Comparative Examples 1 to 4 as described above, according to JEOL 1467 of the Japan Electric Industry Standard. The deodorizing performance was evaluated according to the deodorizing performance test of the household air purifier. At this time, the operation was performed by turning on the ultraviolet lamp newly installed in the new and fresh air blower, and the deodorizing performance was evaluated based on the number of endured cigarettes. In addition, the deodorizing performance and the life of the filter can be understood from the number of endurable cigarettes. The results are shown in Table 1.

<Evaluation of Acetaldehyde Removal Performance> A new fresh air blower was installed in which the photocatalytic deodorizing filters and deodorizing filters of Examples 1 to 5 and Comparative Examples 1 to 4 were incorporated as described above. It established the New鮮風machine in it to the chamber of 1m ³ to be used for deodorizing performance test of household air cleaner of NEC industry standard JEM1467. Acetaldehyde was injected so that the concentration of acetaldehyde in the chamber became 100 ppm. The ultraviolet lamp newly installed in the new winder was turned on, and after operating for 3 hours, the residual concentration of acetaldehyde was measured with a detector tube to determine the acetaldehyde deodorizing performance. The results are shown in Table 1.

<Measurement of Pressure Loss> The pressure loss at 2 m / sec of the photocatalyst deodorizing filters and deodorizing filters of Examples 1 to 5 and Comparative Examples 1 to 4 was measured. Table 1 shows the results.

<Degradation of base material> The photocatalytic deodorizing filters of Examples 1 to 5 and Comparative Examples 1, 2, and 4 were applied with an ultraviolet intensity of 3 mW.
Irradiation was performed for 100 hours under the condition of / cm 2 to check the degree of deterioration of the filter. The degree of deterioration was slightly bent, and the results of observation are shown in Table 2.

[0066]

[Table 1]

[0067]

[Table 2]

[0068]

According to the photocatalyst deodorizing filter characterized in that at least the photocatalyst and the adsorbent are supported on a three-dimensional network structure protected by an inorganic binder, the deodorizing performance is superior to the results of the previous embodiment. It can be seen that the photocatalytic deodorizing filter can efficiently remove aldehydes, has a small pressure loss, and has a long life. Further, harmful substances such as malodorous substances and bacteria can be decomposed and removed by photocatalysis, and aldehydes and the like generated by decomposition of the harmful substances can be adsorbed. Therefore, the photocatalyst deodorizing filter of the present invention can be used in various fields as a deodorizing filter for air purifiers, air conditioners, air conditioners, vacuum cleaners, automobiles, and the like.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B01J 20/18 B01D 53/34 116J 35/02 53/36 H 35/04 331 F-term (Reference) 4C080 AA05 AA07 BB02 HH05 JJ05 KK08 LL03 MM02 NN04 NN06 NN22 QQ03 4D002 AA32. DA03 FA14 GA18 GA40 4G069 AA03 AA08 BA01A BA04A BA04B BA10A BA10B BA22A BA22B BA48A BB04A BC35A BC43A BC60A BE01B BE19B CA10 CA17 EB11 EB12X EB12Y EB15Y EC02Y EC03Y EC22Y FA03 FB14 FB15

Claims (4)

[Claims] 1. A photocatalytic deodorizing filter characterized in that at least a photocatalyst and an adsorbent are supported on a three-dimensional network structure protected by an inorganic binder. 2. The photocatalytic deodorizing filter according to claim 1, wherein the number of cells of the three-dimensional network structure is 6 to 35 cells / 25 mm. 3. The photocatalytic deodorizing filter according to claim 1, wherein the three-dimensional network structure is a plastic foam. 4. The photocatalytic deodorizing filter according to claim 1, wherein the adsorbent is a high silica zeolite.