JPH06319788A - Deodorizing apparatus and manufacture thereof - Google Patents

Abstract

PURPOSE:To improve the peeling resistance and deodorizing catalytic characteristics of a catalyst layer by forming an oxide-based catalytic layer on the surface of a radiation fin comprising aluminum formed with a specified surface roughness through an aluminum oxide layer to fix the radiation fin on a heating body. CONSTITUTION:In the execution for a PTC hot air heater with a deodorizing catalyst, aluminum electrode sections 2 and 3 are junctioned electrically on both sides of a barium titanate based ceramics semiconductor 1 having a resistance-temperature characteristic as positive temperature characteristic (PTC characteristics) as heating body and a radiation fin is fixed closely on the electrode parts 2 and 3 of such a PTC heating body 1. The radiation fin comprises fin parts 7a and 7b formed by bending an aluminum plate and aluminum substrates 6a and 6b on which the fin parts 7a and 7b are fixed. Irregularities with a surface roughness of above 10mum are formed on a radiation surface by a sand blasting method and a catalyst layer is formed on the surface thereof through an aluminum oxide layer with a thickness of 2-20mum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deodorizing device using a deodorizing catalyst. More specifically, it is an adsorbent for adsorbing odors, a catalyst material for decomposing adsorbed odors, and heating the catalyst material. The present invention relates to a specific configuration of a deodorizing device including a heating element and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, as a result of abundant life, there is a strong demand to remove odorous components existing in the living environment, and various deodorizing devices have been developed and commercialized.

One of them is a system using a catalyst which adsorbs an odor component and decomposes the odor component into a harmless and odorless component by heating it at room temperature or heating, and various structures have been proposed for its constitution. ing. For example, JP-A-53-106668
As described in US Pat. No. 6,096,839, a honeycomb-structured PTC thermistor is used as a heat source for heating a catalyst, and a granular catalyst is disposed thereon. With this configuration, a gas containing an odorous component is sucked in by an air blower through the openings of the honeycomb body, the odorous component is adsorbed on the granular catalyst, and the catalyst is periodically heated by the PTC thermistor, and the adsorbed odorous component is harmless. , Which decomposes into an odorless gas. Also, as another example,
As disclosed in Japanese Unexamined Patent Publication (Kokai) No. Hei 2-213080, there is an application to a warm air type electric kotatsu, which has a structure in which a deodorizing catalyst is applied to the surface of a quartz tube heating element of the kotatsu to remove an odor component. The catalyst is adsorbed and the catalyst is heated by the heating element to decompose odorous components.

[0004]

However, the above-mentioned method in which the granular catalyst is packed has a serious drawback that the fine powder of the powdery catalyst is easily scattered by the blown air. Further, in order to decompose the adsorbed components, it is necessary to heat the granular catalyst to the activation temperature, but few granular catalysts adhere to the heating element, and most of the catalysts gradually rise in temperature. Therefore, it has a problem that the adsorbed odor component is desorbed before it is decomposed.

The method of forming a catalyst layer on a quartz tube heating element has a small surface area, so that the amount of odor adsorbed is small, and the method can be applied only in a limited narrow space. Since it is applied on a material with poor thermal conductivity, it is not possible to quickly raise the catalyst temperature to a temperature at which the catalytic function works, and while the temperature of the catalyst is rising, the odorous components adsorbed earlier Had a drawback that it was desorbed without being decomposed at all.

Since the catalyst does not have good catalytic performance at room temperature, it is generally used by activating the catalyst by heating it. When decomposing an adsorbed odor component, the catalyst layer must be quickly heated to the activation temperature. I have to. If this heating rate is slow, the adsorbed odorous components are desorbed without being decomposed into harmless and odorless substances. Further, in order to stably treat odorous components for a long time, it is necessary to increase the surface area of the catalyst layer without increasing the size of the deodorizing device. As one method that can satisfy these items, a structure in which a catalyst layer is directly coated on an aluminum radiating fin that is excellent in thermal conductivity and is inexpensive is considered. However, there is no product with a structure in which the catalyst is directly applied to the aluminum radiating fin. The reason is that when a catalyst having a large difference in thermal expansion coefficient is directly attached to aluminum metal, it peels off by a slight thermal shock, and an underlayer for solving it, that is, a difference in thermal expansion coefficient is relaxed. At the same time, the undercoating material for preventing the corrosion of aluminum, which occurs because the catalyst material absorbs water well, could not be found. Aluminum enamel for the purpose of protecting aluminum has long been known as one candidate material.

However, the peeling of the catalyst layer due to the difference in thermal expansion can be solved with aluminum enamel, but the enamel itself is glass, and in order to bring out its effect, it is 0.2.
A thickness of about 0.5 mm is required. Therefore, mechanical impact may cause cracks in the enamel layer, or the enamel layer may be too thick to heat and cool quickly. When attaching the enamel to the enamel, if there is a difference in the thickness of both sides of the adhered enamel layer, bending occurs when the enamel layer is baked and cooled, or the enamel itself has high rigidity and the enamel layer is formed in advance on the aluminum thin plate, After that, since it is not possible to fold it to form a narrow pitch radiating fin as in the present invention, or it is very difficult to apply enamel to a narrow pitch radiating fin that has been made in advance, it is an object of the present invention. It is difficult to apply it to the radiation fin.

[0008]

In order to solve the above-mentioned conventional problems, the deodorizing device of the present invention has a surface roughness of 10 in advance.
An oxide-based catalyst layer is formed on the surface of a radiating fin made of aluminum having irregularities of not less than μm through an aluminum oxide layer having a thickness of 2 to 20 μm, and the radiating fin is fixed to a heating element. .

[0009]

According to the structure of the present invention, the surface has a thickness of 2 to 20 μm.
The catalyst material is directly coated on the radiating fin made of aluminum having an aluminum oxide layer of m, and the radiating fin has a structure in which the radiating fin is in intimate contact with and bonded to the heating element. Conduction is very fast, and it is possible to quickly raise the catalyst temperature to the decomposition temperature of the specified adsorbed odor component, and to adsorb the quick odor component,
Decomposition can be done.

Further, since the aluminum oxide layer does not cause a problem such as peeling even if it is bent, it is possible to form a radiating fin with a narrow pitch by subjecting a continuous aluminum plate to a main treatment in advance and then bending. There are also advantages.

[0011]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a block diagram of a PTC warm air heater with a deodorizing catalyst equipped with the deodorizing device of the present invention. In FIG. 1, reference numeral 1 indicates a temperature characteristic (PTC characteristic, PTC: Positive Temperature Coeffi
The barium titanate-based ceramics semiconductor device (having eight elements each having a size of 25 × 15 × 3 mm in width, length, and thickness are arranged) and has a Curie point (resistivity of the semiconductor device). The temperature at which the value becomes twice the normal temperature) is changed to 250 ° C., and aluminum electrode plates 2 and 3 are electrically bonded to both surfaces thereof. The method of joining is, for example, National Technical R
eport, Vol.31, No.3, p69-77, Jun, 1985 ,. Stainless steel terminals 5a and 5b are respectively joined to one ends of the aluminum electrode plates 2 and 3 by crimping with 4a and 4b. The PTC heating element 1
The size of the heat generating part is 25 × 120 in width, length and thickness.
It is × 4 mm. The electrode parts 2, 3 of the PTC heating element 1
The heat radiation fin is fixed in close contact with. This radiating fin is a fin portion 7 formed by bending an aluminum plate.
a, 7b (in the embodiment, the size is width, length and thickness are 2
4 × 120 × 15 mm, fin pitch 1.5 mm) and the aluminum substrate 6a to which the fin portions 7a and 7b are fixed,
6b, and the aluminum substrates 6a and 6b are joined to the electrode portions 2 and 3 by a heat resistant silicone resin.
The details of the heat radiation fin are as follows: the ridges 8 and 9 parallel to each other on one surface of the aluminum substrates 6a and 6b having a purity of 99% or more;
10 and 11 (having the same ridge on one side of 6b) are formed, and on the ridge portion side of the aluminum substrates 6a and 6b, a width slightly smaller than the inner space between the ridges 8 and 11, Aluminum radiating fins 7a, 7b bent in a zigzag shape having a purity of 99% or more are joined.
The joining is performed by radiating heat in which bent portions of the zigzag heat radiating fins are formed with notches 12a and 13a slightly larger than the ridge portion size at positions corresponding to the ridge portions 9 and 10 of the aluminum substrate 6a. After the fin portion 7a is inserted into the aluminum substrate 6a so that the ridge portion and the notch portion are aligned with each other, the ridge portions 9 and 10 are attached to the radiating fin portion 7a.
The ridges 8 and 11 are pressed and deformed from above between a, and the ridges 8 and 11 are joined inward by bending and caulking from the side toward the radiating fins (same for 6b).

On both surfaces of the heat radiation fins 7a and 7b and on the ridge-formed surfaces of the aluminum substrates 6a and 6b, as shown in the enlarged cross section of the heat radiation fins in FIG. The formed aluminum oxide layer 15 and the catalyst layer 16 are formed in close contact therewith. The thickness of the aluminum oxide layer 15 is 2 to 20 μm.
m is suitable. Concavities and convexities are previously formed on the surface of the aluminum 14 on which the catalyst layer 16 is formed by a sand blast method, and the average roughness of the concavities and convexities (depth of the concavities and convexities) on the surface is, for example, 10 to 50 μm. The surface on which the irregularities are formed is formed by a general anodizing method by anodization, for example, aluminum is used as an anode in 10% sulfuric acid solution at 10 to 15 V, current density 1 A / dm ² , liquid temperature 2
After performing anodic oxidation at 0 to 22 ° C. for 60 minutes, the aluminum oxide layer formed by boiling in boiling water is sealed to seal fine holes.

The catalyst layer 16 is formed in close contact with the aluminum oxide layer 15. The catalyst forming method is, for example, aluminum oxide, titanium dioxide, barium oxide,
In order to strengthen the bond between at least two kinds of oxide materials of cerium oxide or manganese dioxide and platinum-palladium supported on them, and the zeolite fine powder and the catalyst and the underlying aluminum oxide layer, a silicic acid anhydride is used. A colloidal solution was mixed to apply a weakly alkaline slurry, which was dried and then heat-treated at 500 ° C. for 30 minutes to form a film.

The unevenness formed on the aluminum is absolutely necessary for fixing the catalyst to the aluminum oxide layer 15, and the anchor effect has a great influence on the adhesion strength of the catalyst. That is, when the average roughness is 10 μm or less, the anchor effect is small, and the applied catalyst layer falls off due to severe mechanical shock or thermal shock. The one having large irregularities does not have a bad influence even if it exceeds 50 .mu.m described above, and if the mechanical strength of the aluminum thin plate to be used has no problem, it is not necessary to care. The thickness of the aluminum oxide layer is 1
If it is less than μm, pinholes and the like remain and corrosion of the underlying aluminum metal occurs, and if it exceeds 20 μm, cracks may occur due to mechanical deformation.

The colloidal solution of silicic acid anhydride is considered to be bonded to the hydroxyl groups on the surface of the oxide mainly by hydrogen bond or siloxane bond, and is important for bonding the catalyst material and aluminum oxide on aluminum. Make a significant contribution.

FIG. 3 shows an example of temperature rise characteristics of the catalyst layer of the deodorizing device manufactured in this example when AC100V was applied. As can be seen from FIG. 3, the catalyst layer reaches a constant temperature in about 100 seconds. In addition, A of PTC heating element 1 alone in FIG.
The surface temperature of the aluminum electrode 2 when C100V is applied is 2
Although the temperature was 45 to 250 ° C., the temperature on the fins with the above-mentioned radiation fins was 235 as shown in FIG.
Since it is ℃, high temperature can be obtained quickly.

FIG. 4 shows an example of the deodorizing characteristics of the deodorizing device produced in this example. This data was described as the initial stage when the deodorizing device was placed in a hermetically sealed container having a volume of 250 liters at an ammonia gas concentration of 6 ppm and the relationship between the residual ammonia concentration in the container at a catalyst temperature of room temperature and the elapsed time was obtained. The curve after regeneration is that after the initial 40 minutes, AC100V was applied to the PTC heating element for 3 minutes to decompose the adsorbed ammonia gas, and then 6 ppm of ammonia gas was again introduced into the sealed container. And the residual rate of ammonia gas. As can be seen from FIG. 4, the decomposition characteristics of the adsorbed gas of this deodorizing device can be achieved in a very short time. It shows that the temperature of the PTC heating element is quickly transferred to the catalyst layer and the catalyst reaches the activation temperature in a short time, demonstrating the effect of the anodized aluminum oxide layer of the present invention.

The adhesion strength of the catalyst layer to the thermal shock of the anodized aluminum oxide layer-catalyst radiating fins of this deodorizing apparatus was examined. After heating the radiation fins to 260 ℃,
Immediately after 20 cycles under conditions of being poured into water at room temperature, there was no change such as peeling of the catalyst layer. Further, the radiating fins of the present deodorizing apparatus were left at 85 ° C.-85% RH for 1000 hours to observe the corrosion state of aluminum, but there was no change and no peeling of the catalyst layer occurred. This result indicates that the aluminum oxide layer having irregularities alleviates the difference in the coefficient of thermal expansion between aluminum and the catalyst material, and the colloidal solution of silicic acid anhydride in the catalyst strongly bonds to the aluminum oxide layer. Prove that you have achieved it.

Aluminum enamel is generally used as a coating material for aluminum metal having resistance to heat treatment at about 500 ° C., and having acid resistance, alkali resistance, and weather resistance. However, many problems exist for the purpose of use such as the present invention. Have That is, if the composition of aluminum is slightly different, enamel glass that matches it is necessary, and if it is ignored, thermal shock causes cracking and peeling of the enamel layer, and the aluminum plate on which the enamel glass layer is formed is The enamel layer is rigid and has no bending resistance, and cracks occur in the enamel layer with a small amount of displacement, and the enamel layer that is formed requires a thickness of several hundred μm or more to reduce pinholes. When the heat of the aluminum radiating plate was transferred to the catalyst, the bending property was worse, and the poor heat conductivity of the enamel layer was a disaster, and quick heating was difficult. Also,
As described above, if a catalyst layer having a small size and a large area is to be obtained, the pitch of the heat radiation fins becomes narrow, and it is very difficult to uniformly apply the enamel layer to the surface of such a narrow fin. Although there is an electrodeposition method, it is not practical to control the composition, and the production cost is high.

Although the radiating fins in this embodiment have been described as being manufactured by the caulking method, for example, the aluminum thin plate 17 bent in a zigzag shape as shown in FIG. 5 is brazed to the aluminum plates 18 and 19. The surface of the heat dissipating fin having a structure joined by means of sandblasting or the like is mechanically formed with irregularities, an aluminum oxide layer is formed on the surface by anodizing, and the heat dissipating fin coated with the catalyst is formed on the surface of the heat dissipating fin by the PTC. The characteristics of the heating element bonded with a silicon adhesive were also measured, and the same favorable results as described above were obtained. This result shows that the present invention can be applied to aluminum metal radiation fins of various shapes.

Further, in the present embodiment, the one using the colloidal solution of silicic acid anhydride was described for the purpose of firmly bonding the catalyst to the aluminum oxide layer, but it was tested that the following materials can be used for this purpose without any problems. Proved by That is, among aluminum oxide, titanium oxide, barium oxide, cerium oxide or manganese dioxide, at least two or more kinds of oxides carrying a small amount of platinum-palladium are mixed with zeolite fine powder as a weak alkaline solution. And a silicon alkoxide-based material, for example, a high-performance inorganic coating material L2003 manufactured by Nissan Chemical Industries, Ltd., and thoroughly mixed with a ball mill to form a slurry, and an aluminum oxide layer having irregularities on the surface of the aluminum radiation fin. Apply on top, dry, 5
It was baked at 00 ° C. for 30 minutes. The ammonia gas adsorption / decomposition characteristics of the catalyst thus formed are not inferior to those described above, and the adhesive strength of the catalyst material is also superior to that obtained when the silicic acid anhydride colloid solution is used. It was

It is known that a silicon alkoxide forms a siloxane bond with a hydroxyl group on the surface of an oxide by a dehydration / condensation reaction, and a strong bond is formed also in the result of this study. That is, the coating strength of the catalyst was measured according to the 6-15 cross cut test of JIS K5400-90 paint general test method and the 8-12 cross cut test (cellophane peeling test) of JIS D0202 general rules for coating of automobile parts. However, peeling did not occur, and its effect was verified. There are many alkoxide materials, and it has been studied that materials other than silicon alkoxide materials can be sufficiently applied for this purpose. In order to improve the adhesion strength of the catalyst, the above-mentioned colloidal solution of silicic acid anhydride or the metal alkoxide solution may be used alone, but there is no problem even if two solutions are mixed and used. Depending on the type of material, mixing may give better results.

(Embodiment 2) FIG. 6 shows a manufacturing process diagram of the deodorizing apparatus of the present invention. The steps 1 to 13 of FIG. 6 are steps of forming the heat radiation fin from the heat radiation fin portions 7a and 7b and the aluminum substrates 6a and 6b of FIG.
In the sand blasting process of 2 and 8 in FIG. 6, both sides of the aluminum thin plate A having the defined dimensions and serving as the radiation fin portions 7a and 7b and the aluminum substrates 6a and 6b.
The unevenness is formed on the surface of the aluminum plate B having the ridges 8 to 11 previously formed by the drawing method.
Next, after removing the stains in the cleaning steps 3 and 9 in FIG. 6, aluminum oxide layers are formed on the aluminum uneven surfaces in the anodization steps 4 and 10, respectively. Next, in order to close the minute through holes of the formed aluminum oxide layer, a sealing treatment is performed in steps 5 and 11. Next, in a bending step 6, the aluminum thin plate A is mechanically bent into a shape as shown in the heat radiation fins 7a and 7b in FIG. 1, and the cutouts 12a, 13a, 12b, 1 are formed.
3b is formed at a predetermined position by a press method. Next step 1
The process proceeds to the second caulking step, and the notches of the fins formed in step 6 are aligned with the ridges of the aluminum substrate with ridges formed in step 11 to mechanically crimp the ridges.

The above steps are performed using a continuous aluminum material. Next, the process goes to a cutting step 13 to cut into a predetermined size to complete the radiation fin. At this stage, unevenness and anodized aluminum oxide layer are formed on the aluminum surface. Next, move to the catalyst coating step of 14,
The radiating fins are dipped into a catalyst slurry that has been adjusted in advance, and the catalyst is pulled up at a predetermined speed to uniformly apply the catalyst. Next, the process proceeds to the heat treatment step 15 and the catalyst is baked. Next 16
Then, the heat radiation fin with catalyst is bonded to both surfaces of the barium titanate-based semiconductor element to both surfaces of the PTC heater 17 to which aluminum electrode plates are bonded in advance so as to be electrically conductive, by a heat resistant adhesive.

According to this manufacturing method, the aluminum oxide layer for improving the catalyst adhesion strength can be formed in advance on the aluminum material in a continuous state, and it is simpler than attaching the undercoating material to the narrow pitch radiating fins later. It can be manufactured accurately and in large quantities. This manufacturing process was made possible because it was discovered that the anodized aluminum oxide layer can withstand bending and is suitable as an undercoat coating material for the deodorizing catalyst of the present invention. This was completely impossible with aluminum enamel, which is a general coating material. In this embodiment, the sandblasting method has been described as the unevenness forming method, but it goes without saying that there is no problem even with the chemical etching method.

(Embodiment 3) A third embodiment of the present invention will be described below with reference to the drawings. An outline of the case where the deodorizing device of the present invention is used as a warm air heater device is shown in FIG. In FIG. 7, 20a and 20b are cross sections of the aluminum radiating fin with the deodorizing catalyst shown in FIG.
Reference numerals 21a and 21b denote aluminum electrodes joined to the heat radiation fins with a heat-resistant adhesive, which are joined to 22 PTC heating elements so as to be electrically connected. 23
Is a motor, a fan 24 is fixed to its shaft, and 25 is a filter for removing dust in the gas to be sucked. When removing odor components in the figure,
When the PTC heating element is at room temperature, only the gas containing the odorous component is sent to the radiating fin by the fan so that the odorous component is adsorbed on the catalyst layer,
When the amount of adsorption becomes saturated, the PTC heating element is periodically heated to decompose the odorous components with a catalyst. At this time, turn off the blower fan. When used as a warm air heater, both the PTC heating element and the blowing fan are turned on. Since the element having the PTC characteristic is used for the heating element, warm air can be obtained almost at the same time as the switch is turned on, and the self-temperature control function, which is a characteristic of the PTC element, works to maintain a constant temperature. it can.

[0028]

As described above, according to the present invention, the oxide-based catalyst layer is formed on the surface of the radiating fin having irregularities formed on the surface thereof through the aluminum oxide layer, and the radiating fin is used as a heating element. It can be used without being peeled off even if the catalyst is directly applied to the radiating fin that also has the function of a hot air heater with drastic temperature changes, and the function of protecting the aluminum radiating fin itself from the corrosive environment I also have. Also, since a very thin undercoating layer is sufficient, the heat of the aluminum radiating fins can be quickly transferred to the catalyst layer, the adsorbed odorous components can be decomposed in a very short time, and the response speed of the deodorizing catalyst characteristics is significantly improved. . In addition, the configuration of the present invention makes it possible to provide a small-sized warm air heater with a deodorizing catalyst that also has a function as a warm air heater. Further, the present invention further has a function that the aluminum oxide layer withstands bending, has a function of relaxing the difference in the coefficient of thermal expansion between the catalyst and the aluminum plate, and has the ability to protect the aluminum plate from the corrosive environment. The fins can be easily manufactured.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a deodorizing device according to a first embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a radiation fin portion in the first embodiment.

FIG. 3 is a temperature rise characteristic diagram of the PTC warm air heater in the first embodiment.

FIG. 4 is a diagram showing an example of deodorizing characteristics of the first embodiment.

FIG. 5 is a perspective view of a radiation fin according to another embodiment of the present invention.

FIG. 6 is a diagram showing an example of a manufacturing process of the deodorizing apparatus of the present invention.

FIG. 7: PT with a deodorizing catalyst using the deodorizing device of the present invention
C warm air heater configuration diagram

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 PTC heating element 2 Electrodes 5a, 5b Terminals 6a, 6b Aluminum plates 7a, 7b Radiating fins 8, 9, 10, 11 Protrusions 12a, 12b, 13a, 13b Notches

Claims (7)

[Claims] 1. An oxide-based catalyst layer is formed on the surface of a radiation fin made of aluminum having a surface roughness of 10 μm or more formed in advance through an aluminum oxide layer having a thickness of 2 to 20 μm. Deodorizing device with fins fixed to a heating element. 2. The deodorizing apparatus according to claim 1, wherein the oxide catalyst layer contains ultrafine particles of silicic acid anhydride or a metal alkoxide material. 3. The heat dissipation fin has an aluminum substrate having a plurality of protrusions formed in parallel with each other on a surface thereof, and an aluminum plate having a notch for engaging with the protrusions at an end bent in a zigzag shape. The deodorizing device according to claim 1, wherein the deodorizing device is made of a plate and is integrated by engaging the notch with the protrusion. 4. The heating element comprises an electrode plate bonded to both sides of a barium titanate-based ceramic semiconductor having positive resistance-temperature characteristics, and an aluminum substrate is bonded and fixed to the electrode plate. The deodorizing device according to claim 3. 5. An aluminum oxide layer having a thickness of 2 to 20 μm is formed on the surface of a radiating fin made of aluminum on which irregularities are formed in advance, and ultrafine particles of silicic acid anhydride are dispersed on the aluminum oxide layer. A method for producing a deodorizing device, comprising applying an oxide catalyst slurry, drying and firing the oxide catalyst layer to form a heat radiation fin, and fixing the heat radiation fin to a heating element. 6. An oxide in which an aluminum oxide layer having a thickness of 2 to 20 μm is formed on the surface of a radiation fin made of aluminum on which irregularities are formed in advance, and a metal alkoxide material is dispersed on the aluminum oxide layer. A method for manufacturing a deodorizing device, characterized in that, after applying a system catalyst slurry, it is dried and baked to form an oxide catalyst layer to form a radiating fin, and the radiating fin is fixed to a heating element. 7. The method for producing a deodorizing device according to claim 5, wherein the aluminum oxide layer is formed by an anodization method.