JP2003310731A - Deodorizing apparatus by photocatalyst and deodorizing method by photocatalyst - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for deodorizing by a photocatalyst and a method for deodorizing by the photocatalyst, with which a greater deodorizing effect is obtained against a malodor generated from inside a duct, in the deodorizing apparatus which utilizes sterilizing and deodorizing functions of ozone generated by a deodorizing means through a photocatalytic system, and utilizes the gas flow guiding duct like generating the malodor caused by bacteria such as mold. <P>SOLUTION: The photocatalytic deodorizing apparatus which is made to remove a noxious material, is provided with a duct 21 constituting an inflow passage for incorporating and circulating a gas including the malodor, an ozone processing filter 27 which is provided at a rear section in the duct 21 and processes the ozone generated in the duct 21, and a high-voltage power supplier section 30 for applying a high voltage to a catalyst reaction device 25. The photocatalytic deodorizing apparatus 20 structured as described above is installed in a gas introduction duct 39 for circulating an air inside or outside of a car, or in an indoor air circulation duct 51. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an odor removing technology for activating a photocatalyst in a duct to remove the toxic substance from a gas containing the toxic substance passing through the duct. The present invention relates to a photocatalytic deodorizing device and a photocatalytic deodorizing method that perform sterilization and deodorization.

[0002]

2. Description of the Related Art Generally, there are a lamp type photocatalyst system and a discharge type photocatalyst system as a deodorizing device using this type of photocatalyst, and these systems remove harmful substances such as ammonia and formaldehyde.

A deodorizing device utilizing this photocatalyst is
It is used not only for deodorization but also for purifying indoor air in a wide range of applications such as houses and passenger cars.

For example, Japanese Unexamined Patent Publication No. 9-39558 discloses a deodorizing box provided in an air passage leading to the vehicle compartment to deodorize the vehicle compartment.

That is, in FIG. 5, an air passage 1 is formed in a dashboard of a vehicle, and an opening 2 of the air passage 1 is formed.
An example in which an inside air / outside air switching damper 6 is provided near the opening 5 side and communicated with the outside of the vehicle through an opening 5 is disclosed.

Further, deodorizing boxes 7 and 8 of the same structure are installed in the portions inside the air passage 1 which are respectively close to the openings 2 and 3.
As shown in FIG. 6, titanium oxide, yttrium oxide, tin oxide, zinc oxide, tungsten oxide, etc., and a deodorizing photocatalyst in which platinum, palladium, rhodium, etc. are supported on these deodorizing boxes 7, 8 are provided. A catalyst body 10 formed by adhering to activated carbon fibers is installed so as to have air permeability.

An ultraviolet lamp 11 is arranged in the vicinity of the catalyst body 10, and when the ultraviolet lamp 11 is turned on, the photocatalyst of the catalyst body 10 irradiated with the ultraviolet rays is activated.

Further, as shown in FIG. 5, a first fan 12 and a second fan 13 are installed in the air passage 1 on the side opposite to the openings 2 and 3 in the deodorizing boxes 7 and 8, respectively. The first fan 12 is a reversible type, and can blow air selectively in any direction, while the second fan 13 can blow air only toward the deodorizing box 8.

[0009]

According to this deodorizing device, when the outside air is introduced into the passenger compartment 4, the ultraviolet lamps 11 are automatically turned on and the deodorizing boxes 7 and 8 are activated. Since the photocatalyst removes harmful substances contained in the outside air, the inside of the vehicle compartment 4 is kept normal.

Further, in this deodorizing device, ozone is generated in the process of performing the deodorizing action utilizing the activation of the photocatalyst by the discharge phenomenon in the air.

As is well known, this ozone b has an adverse effect on the human body, so that it is normally subjected to waste ozone treatment.

However, this generated ozone b
It has a harmful effect on the human body, but it has been previously confirmed that it has a bactericidal action and a deodorizing action against mold and the like.

The fungi such as mold are prone to a proliferating environment inside the duct through which a gas, for example, the outside air g flows, and cause an offensive odor.

Therefore, if the function of sterilization and deodorization by ozone is provided inside the duct of this type where molds such as molds are easily generated, the odor can be further removed.

The present invention has been made in view of the above points, and the sterilization and deodorizing action of ozone generated by a photocatalytic deodorizing means is such that an offensive odor is generated due to the generation of fungi such as mold. In a deodorizing device using a duct that guides the inflow of various gases, a photocatalytic deodorizing device and a deodorizing method capable of further deodorizing the odor generated in the duct, and decomposing and sterilizing harmful substances The main purpose is to provide.

Another object of the present invention is to focus on the sterilization and deodorizing action of ozone generated by a photocatalytic deodorizing means, and to apply it to a car air conditioner or a vehicle air circulating device in a vehicle such as a passenger car. Another object of the present invention is to provide a vehicle using a photocatalytic deodorizing device for obtaining a further deodorizing effect.

[0017]

In order to achieve the above object, according to the invention of claim 1, a state in which a photocatalyst of a photocatalytic reaction device is activated is formed in a duct, and a gas containing a harmful substance is generated. By taking in or circulating in the duct, in a photocatalytic deodorizing device for decomposing harmful substances from a gas containing harmful substances, a photocatalytic reaction device provided in the front stage of the duct, and provided in the rear stage of the duct, Provided is a photocatalytic deodorizing device comprising an ozone treatment filter for treating ozone generated in a duct and a high-voltage power supply unit for applying a high voltage to the photocatalytic reaction device.

Therefore, in a deodorizing device using a duct that guides the inflow of gas that produces an offensive odor due to the generation of fungi such as mold, the sterilizing and deodorizing action of ozone generated by the photocatalytic deodorizing means. It is possible to provide a photocatalytic deodorizing device capable of further enhancing the deodorizing effect on the odor generated in the duct.

In order to achieve the above object, according to the invention of claim 4, the high-voltage power supply unit is supplied with power from either an engine starting battery or a solar cell mounted on a vehicle. A photocatalytic deodorizing device according to claim 3.

Therefore, focusing on the sterilization and deodorizing action of ozone generated by the photocatalytic deodorizing means, the present invention is applied to a car air conditioner device and a vehicle air circulating device in a vehicle such as a passenger car to obtain a further deodorizing effect. A photocatalytic deodorizing device can be provided.

In order to achieve the above-mentioned object, according to the invention of claim 7, the photocatalyst of the photocatalytic reaction device is activated in the duct, and a gas containing a harmful substance is taken into the duct. Alternatively, in the photocatalytic deodorization method of removing harmful substances from the gas containing the harmful substances by circulating, from the gas containing the harmful substances,
It is characterized in that the harmful substance is decomposed by a photocatalytic reaction, and the bacteria are sterilized or deodorized in the duct by utilizing the sterilizing or deodorizing action of ozone generated by the action of the photocatalytic reaction. A photocatalytic deodorizing method is provided.

Therefore, in a deodorizing apparatus using a duct for guiding the inflow of gas that produces an offensive odor due to the generation of fungi such as mold, the sterilizing and deodorizing action of ozone generated by the photocatalytic deodorizing means. It is possible to provide a photocatalytic deodorizing method capable of further enhancing the deodorizing effect on the odor generated in the duct.

[0023]

Embodiments of the photocatalytic deodorizing apparatus and deodorizing method of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows the outline of the first embodiment of the photocatalytic deodorizing apparatus of the present invention.

The photocatalytic deodorizing device 20 of the first embodiment
Is a gas containing harmful substances such as ammonia and formaldehyde, for example, air inside the vehicle 31 (hereinafter referred to as “gas a”) is passed through the duct 21 to decompose and remove the harmful substances in the duct 21. It is a configuration that is adapted to do.

The photocatalytic deodorizing device 20 includes a discharge type photocatalytic deodorizing device and a lamp type photocatalytic deodorizing device. For example, the discharge type photocatalytic deodorizing device 20 having a great deodorizing effect is used.

The odor source that causes the odor is
Tobacco, sick house, garbage, food, etc.

Further, as harmful substances generated from these odor generating sources, for example, (Table 1) [Application (cause of odor generation)
Different odor components and deodorizing method].

Particularly, according to the discharge type photocatalytic deodorizing device 20 used for the purpose of deodorization, as shown in "Deodorizing method" of (Table 1), it is remarkable for all purposes (indoor air purification and deodorizing). The situation is shown that various deodorizing effects can be obtained.

The photocatalyst deodorizing device 20 in the present invention adopts the deodorizing method using the discharge type photocatalyst, and when the photocatalytic deodorizing device 20 is activated, the action accompanying the activation of the photocatalyst,
In other words, the ozone b generated by the discharge in the air also has a sterilizing effect and a deodorizing effect.

This ozone b has a harmful effect on the human body, but is known to have the effect of decomposing and removing harmful substances including odorous components, in addition to the bactericidal action such as mold.

[0032]

[Table 1]

According to this photocatalytic deodorizing device 20, harmful substances (including odorous components) such as outside air g and gas a are introduced into the duct 2.
1 is used to utilize the sterilization and deodorizing action of ozone b generated by the action associated with the activation of the photocatalyst.

The photocatalytic deodorizing device 20 is a discharge type photocatalytic deodorizing device provided with a photocatalytic reaction device 25 provided in a duct 21 for taking in or circulating a gas a containing a harmful substance.

The photocatalyst deodorizing device 20 includes a dust collecting filter 23, a dust collecting filter 23, and a dust collecting filter 23.
The blower 24 and the photocatalytic reaction device 25 are sequentially arranged.

Further, an ozone treatment filter 27 is provided on the downstream side of the photocatalytic reaction device 25 installed at the front stage of the duct 21 via a duct space 26.

The ozone treatment filter 27 is provided in the duct 2
It is arranged in the vicinity of the opening 22b provided in the terminal part of the rear part of the first unit.

The ozone treatment filter 27 has an exhaust ozone treatment function capable of ozone treatment in order to prevent the ozone b generated by the action associated with the activation of the photocatalyst of the photocatalytic reaction device 25 from flowing out.

On the other hand, the photocatalytic reaction device 25 has a structure in which electrodes having a honeycomb structure, for example, honeycomb electrodes 29, 29 are arranged on both sides of the photocatalytic module 28.

As the honeycomb electrodes 29, 29, those having a small air resistance are used so as not to interfere with the reinforcement of the electrodes themselves and the flow of the gas a.

When a high voltage is applied to the photocatalyst module 28 from the honeycomb electrodes 29, 29, the photocatalyst is activated and the deodorizing action is promoted.

The dust collecting filter 23 removes dust contained in the gas a flowing into the duct 21 and prevents clogging by dust in the photocatalytic reaction device 25.

The blower 24 is provided so as to forcibly take in or circulate the gas a containing a harmful substance from the front part to the rear part of the duct 21.

In the duct space 26 between the photocatalytic reaction device 25 and the ozone treatment filter 27, the photocatalytic reaction device 2 is provided.
The harmful substance including odor is decomposed and removed by the chemical action by the activation of 5 and at the same time, the gas a1 including ozone b generated by the photocatalytic reaction is floated so as to be filled.

Next, the operation will be described.

When a high voltage required to activate the photocatalytic module 28 of the photocatalytic reaction device 25 is applied from the high-voltage power supply section 30, the photocatalytic reaction device 25 operates.

At the same time, the blower 24 in the duct 21 is operated and the gas a flows in through the opening 22a of the duct 21.

The gas a flowing in from the opening 22a has its dust removed by the dust collecting filter 23 and reaches the photocatalytic reaction device 25 through the blower 24.

The honeycomb electrode 29 of the photocatalytic reaction device 25,
The predetermined high voltage is applied from 29 to the photocatalyst module 28.

Then, a discharge phenomenon in the air occurs between the honeycomb electrodes 29, 29, and the photocatalyst of the photocatalyst module 28 is activated.

Ozone b is generated by the discharge in the air.

The ozone b decomposes and removes harmful substances containing odorous components, whereby bacteria and odorous components are removed from the gas a.

The ozone b, which is filled with the gas a, comes into contact with the fungus c such as molds generated on the inner wall 21a extending to the rear part of the duct 21 and acts to remove the fungus c. The ozone b remaining in the gas a reaches the ozone treatment filter 27 and is subjected to exhaust ozone treatment.

The gas a2 purified by removing harmful substances flows out from the opening 22b at the end.

Although residual ozone is present in this gas a2, its content must be suppressed to a standard value of 0.1 ppm (working environment standard) or less.

Next, a vehicle using the photocatalytic deodorizing device according to the second embodiment using the photocatalytic deodorizing device according to the present invention will be described with reference to FIGS.

FIG. 2 shows an outline of a vehicle using the photocatalytic deodorizing device of the present invention.

A vehicle 31 such as a private car is provided with a car air conditioner 32.

The car air conditioner 32 has an outside air g from the gas inflow duct 39 to the engine room 38 of the vehicle 31.
And a gas inflow path d for inflowing the air and a room air circulation path e for circulating the gas a from the vehicle compartment 34 in a closed loop via the indoor air circulation duct 51.

The photocatalytic deodorizing device 53 shown in FIG. 1 of the first embodiment of the present invention is installed across each of these gas inflow ducts 39 and duct branch pipes 41a to 41c.

That is, from the gas inflow path d to the duct branch pipe 4
A gas inflow duct 39 communicating with the vehicle compartment 34 is provided so that the outside air g is taken into the vehicle compartment 34 via 1a to 41c.

On the side of the passenger compartment 34, as shown in FIG.
In the driver's seat portion, duct branch pipes 41a to 41c are provided extending from the gas inflow duct 39, and each of the duct branch pipes 41a to 41c has three air outlets 40a to 40a at the open end on the vehicle compartment 34 side.
40c is provided.

As shown in FIG. 2, the dust collecting filter 43, the blower 44, the blower 44,
A photocatalytic reaction device 45 is installed.

In the rear stage, the evaporator 46 of the refrigeration cycle device (not shown) and the air outlets 40a to 40 are provided.
The ozone treatment filters 27a to 27c are arranged in proximity to the c section, respectively.

Therefore, the duct space 55 in which the evaporator 46 is arranged is formed between the photocatalytic reaction device 45 and the ozone treatment filters 27a to 27c.

The ozone treatment filters 27a to 27c
Is a filled volume of gas containing ozone b (duct space 5
5) is maximized to maximize the decomposition ability of ozone b, the photocatalytic reaction device 45 and the openings (air outlets 40a to 40c) to the vehicle interior 34 are provided in the openings.

The structure of the photocatalytic deodorizing device 53 is the same as that of the photocatalytic deodorizing device 20 shown in the first embodiment of FIG. 1, and therefore its explanation is omitted.

The car air conditioner 32 includes a dust collecting filter 43 provided at the opening of the gas inflow duct 39 and the outside air g.
The air blower 44 for letting air into the gas inflow duct 39, the evaporator 46 installed in the duct space 55, and the air outlets 40a-40c provided at the open ends of the duct branch pipes 41a-41c.

For example, the indoor air circulation passage e for circulating the gas a in a closed loop at the time of cooling / heating is the indoor air circulation duct 5
The photocatalytic reaction device 45 is directly circulated from the opening end of No. 1 and the gas a is circulated by the blower 52.

Due to this closed air circulation loop, the air in the vehicle compartment 34 is forcedly circulated by the blower 52, and the vehicle compartment 34 is cooled and heated.

The heating can be performed, for example, by the heat pump action of the refrigeration cycle.

The duct space 55 of the gas inflow duct 39
Since the gas a circulates for cooling and heating during operation of the car air conditioner 32, bacteria are generated on the evaporator 46 and its surroundings due to adhesion of dew drops and temperature rise, and especially on the inner wall of the gas inflow duct 39. , For example, causes mold to grow and give off a strange odor.

The photocatalytic reaction device 45 is activated by application of a high voltage from the power source section.

Hereinafter, description will be made with reference to FIG.

As a power source, the engine starting battery 3 is used.
A power supply connection circuit 56 is provided for connecting 6 and the solar cell 35.

The description of the structures of the engine starting battery 36 and the solar cell 35 of the power supply connection circuit 56 will be omitted.

The power supply from the power sources for the engine starting battery 36 and the solar battery 35 can be selectively switched and connected by operating the main key switch 37.

A timer changeover switch 42 is provided between the main key switch 37 and the photocatalytic reaction device 45.
Is provided.

The timer changeover switch 42 does not constantly operate the photocatalytic deodorizing device 53, but the vehicle interior 34
It is provided in order to operate so that the electric power can be used efficiently so that the deodorization of the inside can be performed as needed and rationally.

Further, for example, it is possible to make an adjustment so that the solar cell 35 side is mainly used during sunshine and the engine starting battery 36 is mainly used during rainy weather.

Next, the operation will be described.

By operating the main key switch 37 of the vehicle 31, the engine starting battery 36 or the solar battery 35 is operated.
Is connected to the photocatalytic deodorizing device 53 via the timer type changeover switch 42.

Further, the start switch (not shown) of the car air conditioner 32 is turned on to turn on the car air conditioner 32.
To start.

Then, the blower 44 is driven and the gas a, for example, the outside air g flows into the gas inflow duct 39 through the dust collecting filter 43.

Gas a flowing into the gas inflow duct 39
Passes through the photocatalytic reaction device 45 installed in the front part of the gas inflow duct 39, and the gas inflow duct 3
9 to the duct space 55 corresponding to the rear stage.

Outside air g passing through this duct space 55
Is the evaporator 4 installed in the duct space 55.
6. The duct branch pipes 41a to 41c and the ozone treatment filters 27a to 27c circulate in this order and flow into the vehicle interior 34.

The outside air g passes through the photocatalytic reaction device 45 in the duct space 55, and in the process, the photocatalytic reaction device 4 is discharged.
By the action of 5, harmful substances such as ammonia contained in the outside air g are decomposed.

At the same time, the action associated with the activation of the photocatalyst,
That is, ozone b is generated by the activation action of the photocatalyst due to the discharge in the air.

The generated ozone b is filled in the duct space 55 of the gas inflow duct 39.

Ozone b filled in the duct space 55
However, the bacteria contact with the fungus such as mold attached to the inner wall surface of the duct facing the duct space 55, and the ozone b acts to remove bacteria.

At the same time, harmful substances such as ammonia are decomposed.

Next, when the blower 52 installed in the indoor air circulation duct 51 of the car air conditioner 32 is driven, the gas a in the vehicle compartment 34 flows into the indoor air circulation duct 51 and passes through the photocatalytic reaction device 45. , And reaches the duct space 55 which is the rear stage of the gas inflow duct 39.

The gas a reaching the duct space 55 is
It sequentially circulates to the evaporator 46, the duct branch pipes 41a to 41c, and the ozone treatment filters 27a to 27c, and flows into the vehicle compartment 34.

The gas a is subjected to the action of decomposing harmful substances by the photocatalytic reaction device 45, like the outside air g flowing from the outside.

The description of the decomposition processing action of the gas a circulating in the indoor air circulation duct 51 is omitted.

According to the above-described embodiment of the present invention, when the air conditioner of the car air conditioner 32, for example, the air conditioner is activated, the dew drops formed on the inner wall of the evaporator 33 and the duct space 55 cause fungi such as mold. Is generated, and the odor generated abnormally due to this is filled with ozone b that fills the duct space 55 to disinfect the bacteria and decompose the odor. It can be prevented.

Even when the car air conditioner 32 is used as a heating device, for example, the duct space 55 creates an environment that promotes the growth of fungi, so that it is extremely efficient as in the case of cooling. It is possible to prevent a bad odor from occurring.

[0098]

EFFECTS OF THE INVENTION According to the present invention, a photocatalytic deodorization that can obtain a further deodorizing effect can be obtained by sterilizing and deodorizing ozone generated by the photocatalyst activating action of the photocatalytic deodorizing means. An apparatus and a photocatalytic deodorizing method can be provided.

Further, according to the present invention, focusing on the sterilization and deodorizing action of ozone generated when the deodorizing action by the photocatalytic method is exerted, the invention is applied to the intake of the outside air in a vehicle such as a passenger automobile and the circulation device of the air inside the vehicle, It is possible to provide a photocatalytic deodorizing device that further obtains a deodorizing effect.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of a photocatalytic deodorizing apparatus that is a first embodiment of the present invention.

FIG. 2 is a diagram showing an outline of a vehicle using a photocatalytic deodorizing device according to a second embodiment of the present invention.

FIG. 3 is a diagram showing a power supply system in a vehicle using a photocatalytic deodorizing device according to a second embodiment of the present invention.

FIG. 4 is an enlarged view of portion A of FIG.

FIG. 5 is a schematic view of a conventional vehicle deodorizing device.

FIG. 6 is an enlarged perspective view of a main part of the vehicle deodorizing device shown in FIG.

[Explanation of symbols]

1 air passage 2, 3, 5 openings 4 car compartment 6 Inside / outside air switching damper 7,8 Deodorization box 10 Catalyst body 11 UV lamp 12 First Fan 13 Second Fan 20,53 Photocatalytic deodorizer 21 duct 21a inner wall 22a, 22b opening 23,43 Dust collection filter 24,44,52 blower 25,45 photocatalytic reactor 26,55 Duct space 27,27a-27c Ozone treatment filter 28 Photocatalyst module 29 Honeycomb electrode 30,54 High voltage power supply 31 vehicles 32 Car air conditioner 33 Evaporator 34 cabin 35 solar cells 36 Engine Starting Battery 37 Main key switch 38 engine room 39 Gas inflow duct 40a-40c Air outlet 41a, 41b, 41 duct branch pipe 42 Timer type changeover switch 46 Evaporator 51 Indoor air circulation duct 56 Power connection circuit a Gas (gas containing harmful substances) a1 Gas containing ozone a2 Gas from which harmful substances have been removed b ozone c fungus d Gas inflow path e Indoor air circulation path g Outside air (gas containing harmful substances)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F24F 7/06 B01D 53/36 J H (72) Inventor Noboru Segawa 2-chome, Suehiro-cho, Tsurumi-ku, Yokohama-shi, Kanagawa No. 4 Toshiba Keihin Office (72) Inventor Naohiko Shimura 2-4 Suehiro-cho, Tsurumi-ku, Yokohama-shi, Kanagawa F-Terms at Toshiba Keihin Office (reference) 3L058 BG03 4C080 AA07 AA10 BB02 BB05 CC01 HH02 JJ01 KK02 MM08 QQ17 4D048 AA22 BA05X BA07X BA41X BB08 CA01 EA01 EA03

Claims (7)

[Claims] 1. A photocatalyst of a photocatalytic reaction device is activated in a duct, and a gas containing a harmful substance is taken in or circulated in the duct,
In a photocatalytic deodorizing device for decomposing harmful substances from a gas containing harmful substances, a photocatalytic reaction device provided in the front stage of the duct and an ozone treatment filter provided in the rear stage of the duct for treating ozone generated in the duct And a high-voltage power supply unit for applying a high voltage to the photocatalytic reaction device. 2. The photocatalytic deodorizing device according to claim 1, wherein the ozone treatment filter is provided with a filter having an ozone removing action. 3. In a vehicle such as a passenger car,
Between the gas inflow duct provided to take in the outside air from the outside of the vehicle or to circulate the air in the vehicle, the photocatalytic reaction device provided in the preceding stage in the gas inflow duct, and the photocatalytic reaction device in the gas inflow duct. A photocatalyst deodorizing device comprising an ozone treatment filter provided at a rear stage of the gas inflow duct so that a duct space is formed, and a high-voltage power supply unit for applying a high voltage to the photocatalytic reaction device. . 4. The photocatalytic deodorizing device according to claim 3, wherein the high-voltage power supply unit receives power from either an engine starting battery or a solar cell mounted on a vehicle. 5. The photocatalytic deodorizing device according to claim 3, further comprising a timer-type changeover switch which is connected between the high-voltage power supply unit and the power supply and is connected only for a predetermined time. 6. The photocatalytic deodorizing device according to claim 5, wherein the changeover switch is a main key switch that operates in conjunction with an operation of an engine start key of the vehicle. 7. A duct in which a photocatalyst of a photocatalytic reaction device is activated in a duct, and a gas containing a harmful substance is taken in or circulated in the duct,
In a photocatalytic deodorizing method for removing harmful substances from a gas containing harmful substances, the harmful substances are decomposed from the gas containing harmful substances by a photocatalytic reaction and removed by ozone generated by the action at the time of this photocatalytic reaction. A photocatalytic deodorization method, which comprises sterilizing bacteria in the duct or decomposing harmful substances by utilizing bacteria or deodorizing action.