JP2932456B2 - Heating element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating element having excellent durability, and more particularly, to a consumer appliance such as a heater, a hot water supply, a dryer, a cooker, a refrigerator, a kotatsu, and an air conditioner. The present invention relates to a heat generating element which can be used as a heat generating element, can effectively adsorb a malodorous component gas which is unpleasant to the human body at the time of use, and can stably maintain its deodorizing ability.

[0002]

2. Description of the Related Art Activated carbon, which has been widely used as a deodorant, needs to be replaced with a new one when its adsorption capacity is deteriorated due to physical adsorption. For this reason, there are drawbacks that management of effectiveness and replacement is complicated, and that long-term use costs are increased. As an alternative to chemical deodorization, a method of oxidizing and decomposing malodorous gas using ozone gas has recently been put to practical use. However, this deodorizing operation requires an ozone generator, and the ozone itself is unpleasant. There is a problem with excess gas treatment due to the presence of tools. In addition, deodorizers composed of oxidizing agents such as potassium permanganate, potassium iodate or hypochlorite, and conversely, deodorants using reducing agents, etc. are also known. The range of use as a consumer deodorant which is required is extremely limited.

[0003] Against this background, the development of oxidative decomposition catalysts that are safe and can be reused has been actively pursued. As a catalytic deodorant utilizing this kind of oxidative decomposition, for example, a catalyst mainly composed of zeolite (JP-A-5-9-9)
No. 8185), one containing zeolite and a noble metal-supported oxide as main agents (Japanese Patent Application Laid-Open No. 5-96176), one containing zeolite and magnesium silicate, or one or more of these and a platinum group metal salt (Japanese Patent Application Laid-Open No. 5-98194
Japanese Patent Application Laid-Open No. 5-98185), one containing a zeolite and an oxide of copper or manganese as main components (Japanese Patent Application Laid-Open No. HEI 5-98185).
JP-A-151938), those in which silver or manganese or a compound thereof is supported on a porous body (Japanese Patent Laid-Open No. 4-1147)
No. 44), and those using a composite oxide of silver and manganese as a main agent (Japanese Patent Application Laid-Open No. 4-200638) have been proposed. In Japanese Patent Application Laid-Open No. 5-96178,
It is disclosed that a catalytic deodorant mainly composed of zeolite and a noble metal-supported oxide is formed on the surface of a casing of a heating element.

[0004]

However, the deodorizing agents of the oxidative decomposition catalyst system according to the prior art do not have a sufficient deodorizing ability, for example, a deodorizing ability for a specific gas such as a sulfur-based malodorous gas such as methyl mercaptan. Poor reproducibility, insufficient oxidative decomposition to maintain the deodorizing ability for a long period of time, or difficulty in regenerating, and other problems remain to be improved. In addition, a material containing a noble metal such as silver or platinum as a main component has a high raw material cost and is expensive.

The present invention has been developed in view of the above-mentioned facts, and it is an object of the present invention to efficiently adsorb unpleasant odorous gas, to have excellent oxidative decomposition properties, and to stably maintain high deodorization for a long period of time. An object of the present invention is to provide an inexpensive heating element capable of maintaining its function.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention comprises a casing and a heating member such as an electric resistance member arranged in the casing. Provided is a heating element characterized by having provided an oxidatively decomposable deodorizing catalyst containing manganese, copper ion-supporting zeolite and copper oxide as effective components.

In the present invention, a tubular or spherical casing made of quartz or glass can be used as the casing. As the heat generating member, a member such as an electric resistance member that can generate heat when energized can be appropriately selected and used. More specifically, as shown in FIG. 1, the heat generating member 1 is generally arranged in a casing 3 while being supported by a holding end 2 made of an insulator or heat-resistant rubber.
Then, an oxidatively decomposable deodorizing catalyst layer 4 is provided on the outer peripheral surface of the casing 3. The method of giving the coating is free. However, by using the oxidatively decomposable deodorizing catalyst in the form of a coating, the coating can be easily and efficiently coordinated only by coating the outer peripheral surface of the casing 3. The method of coating is free, and any appropriate method such as dip coating, spray coating, electrostatic coating, knife or roll coater method, screen printing, etc. can be adopted. In order to improve the adhesion of the oxidatively decomposable deodorizing catalyst layer 4 to the casing 3, it is possible to form small irregularities on the casing surface, or to degrease the surface of the quartz or glass body constituting the casing. Good.

In the present invention, active manganese dioxide refers to porous manganese dioxide having a large specific surface area obtained by at least wet oxidative decomposition of a manganese salt, and having a large specific gravity obtained by electrolytic oxidation such as for a battery. The material is different from the material. Therefore, it should be understood that, when represented by the general formula MnO _X, it is often in the range of 1.8 <x <2.0, and is not necessarily MnO ₂ . The composition of the activated manganese dioxide has a nitrogen adsorption specific surface area (BET) of 50 m ² / g or more,
Preferably, those having a mass of 200 to 1000 m ² / g are suitably used.

Such active manganese dioxide is obtained, for example, by subjecting a divalent manganese salt to hydrolysis and then an oxidation treatment, a reaction product of a divalent manganese salt and a permanganate,
A method of neutralizing a mixed solution of a copper salt and a divalent manganese salt, coprecipitating the mixed solution with a metal hydroxide, and oxidizing the metal hydroxide, a method of using a permanganate for the oxidation treatment, and the like. Can be. Further, according to the experience of the present inventors, it is preferable to use active manganese dioxide supporting copper ions as the active manganese dioxide.

The copper ion-carrying zeolite is obtained by substituting and supporting copper ions with zeolite cations by utilizing the ion exchange capacity of zeolite. Zeolite A, zeolite L, zeolite X,
Examples include zeolite Y, zeolite P, clinoptilolite, mordenite, and other high silica zeolites, but zeolite A is preferably used in view of performance and cost. Copper ions are usually Cu ²⁺
However, it may be a complex ion. The amount of copper ions carried is not particularly limited, but is preferably at least 30% or more based on the cation exchange capacity of the zeolite.

Examples of the copper oxide include copper oxide, cuprous oxide, copper hydroxide, and basic copper oxide. Among them, copper oxide is preferably used.

[0012] The composition ratio of the components can be varied depending on the respective physical properties and the intended use, but its range
Boxes indicate activated manganese dioxide: zeolite supporting copper ions:
The composition ratio of the copper oxide is from 1: 0.5 to 1: as a weight ratio.
The range is 0.05 to 0.5.

The oxidatively decomposable deodorizing catalyst according to the present invention is prepared by mixing the above three components in a predetermined composition ratio and uniformly mixing them in a dry or wet system. The form of application to the casing surface is free, but from the viewpoint of ease of application to the casing and prevention of falling off, it is attached to the outer periphery of the casing as a molded body formed into a desired shape, rather than as a mixed powder. Or as a slurry-like coating.

When the form of use is a molded article or paint as described above, the active ingredient manganese dioxide, zeolite carrying copper ions and copper oxide may be added, if necessary, to a three-component system such as resin, It is prepared by appropriately adding an organic or inorganic binder such as silica sol, a paint vehicle and the like.

[0015]

The oxidatively decomposable deodorizing catalyst used in the heating element of the present invention exhibits an extremely efficient deodorizing effect on a small amount of complex polluting malodorous gas. Although the details of the deodorizing mechanism have not been elucidated yet, it is presumed that the three-component system constituting the catalyst is based on an action of increasing the deodorizing efficiency by mutually acting.In particular, active manganese dioxide and copper ion-supported zeolite are Synergistically exerts an excellent deodorizing function for removing sulfur-based malodorous gases such as methyl mercaptan.

In the present invention, the oxidative decomposable deodorizing catalyst is provided on the surface of the casing containing the heat generating member.
By causing the heat generating member to generate heat, the oxidatively decomposable deodorizing catalyst can be heated via the casing. And
Under the above-mentioned heating, the malodorous gas adsorbed by the catalyst is easily decomposed by active manganese dioxide having high oxidizing ability, and the deodorizing ability can be easily recovered and regenerated. For example, for nitrogen-based malodorous gases such as trimethylamine, it is oxidized to NO _2, effectively deodorizing ability is played.

The heating element of the present invention can be used in place of conventional various heating elements, and in particular, a heating element for a heating appliance such as a stove or a kotatsu, a heating element for heating a hot water supply device, and a heating device for a dryer. It can be used as a heating element mounted on various consumer electric appliances such as a heating element for cooking, a heating element for grill of a cooker, a heating element for defrosting a refrigerator, and a heating element for heat sterilization of an air conditioner.

[0018]

EXAMPLES Hereinafter, specific examples of the present invention will be described in comparison with comparative examples. Example 1 (1) Preparation of oxidatively decomposable deodorizing catalyst paint Nitrogen adsorption specific surface area containing 25% by weight of CuO (BE)
T) Zeolite A supporting copper ions (11.0% as CuO) was added to 60 parts by weight of active manganese dioxide of 290 m ² / g.
50 parts by weight (weight% supported, average particle size: 2.35 μm) and 10 parts by weight of copper oxide were blended, and 100 parts by weight of water was added, followed by wet mixing. Then, silica sol (SiO: 30
(% By weight) in a ball mill together with 50 parts by weight, and a mixing operation was performed until the mixture became uniform to prepare a coating material for an oxidatively decomposable deodorizing catalyst. This paint is applied twice by spray coating over a range of 258 mm to the center of the glass tube surface of a heating element in which a 140 W heating electric resistor is arranged in a glass tube having a total length of 326 mm and an outer diameter of 10.5 mm. and, then dried 1 hour at a temperature of 400 ⁰ C to form a coating layer of oxidative degradation deodorizing catalyst.

(2) Evaluation of Deodorizing Ability The heating elements of the above Examples were subjected to a deodorizing test of methyl mercaptan and trimethylamine by the following test method, and the deodorizing ability was evaluated. The results are shown in Table 1. Methyl mercaptan deodorization test method: The heating element of the example was placed in a 10-liter gas collecting bag, and the methyl mercaptan concentration in the gas collecting bag was adjusted to 20 ppm. Thereafter, the concentration of methyl mercaptan in the gas collecting bag after 1 hour was measured with a gas tech detector tube, and the residual ratio was determined. A heating element not covered with the oxidatively decomposable deodorizing catalyst was placed, and measured in the same manner as a blank. Trimethylamine deodorizing test method: The heating element of the example was placed in a 10-liter gas collecting bag, and the concentration of trimethylamine in the gas collecting bag was adjusted to 20 ppm. Thereafter, the concentration of trimethylamine in the gas collection bag after 1 hour was measured with a gas tech detector tube, and the residual ratio was determined. In addition, a heating element not covered with the oxidatively decomposable deodorizing catalyst was put therein, measured in the same manner, and used as a blank.

Example 2 70 parts by weight of active manganese dioxide (specific surface area: 246 m ² / g), zeolite X supporting copper ions (11.
A coating composition of an oxidatively decomposable deodorizing catalyst was prepared under the same conditions as in Example 1 except that the composition ratio was 45 parts by weight (7% by weight supported, average particle size 2.76 μm) and 5 parts by weight of copper oxide. This coating material was applied to the surface of the glass tube of the same heating element as in Example 1 under the same application conditions, the deodorizing ability was evaluated, and the results are shown in Table 1.

Example 3 Nitrogen adsorption specific surface area (BE) containing 21% by weight of CuO
T) 50 parts by weight of zeolite A supporting copper ions (8.6% by weight supported as CuO, average particle size 2.56 μm) and 65 parts by weight of activated manganese dioxide of 268 m ² / g and cuprous oxide (average particle size of 2. A coating composition of an oxidative decomposable deodorizing catalyst was prepared under the same conditions as in Example 1 except that the composition ratio was 5 parts by weight. This coating material was applied to the surface of the glass tube of the same heating element as in Example 1 under the same application conditions, the deodorizing ability was evaluated, and the results are shown in Table 1.

Comparative Example 1 100 parts by weight of the zeolite A carrying copper ions used in Example 1 was added to 20 parts by weight of water and wet-mixed, and then 30 parts by weight of silica sol (SiO ₂ : 30% by weight) was added, followed by a ball mill. A paint was prepared by uniformly mixing. This paint was applied to the surface of the glass tube of the same heating element as in Example 1 under the same application conditions, and the deodorizing ability was evaluated.
It was also attached to.

Comparative Example 2 A coating material was prepared in the same manner as in Comparative Example 1 by adding 70 parts by weight of active manganese dioxide (specific surface area: 228 m ² / g), 50 parts by weight of zeolite A and 90 parts by weight of water. This coating material was applied to the surface of the glass tube of the same heating element as in Example 1 under the same application conditions, the deodorizing ability was evaluated, and the results are shown in Table 1.

Comparative Example 3 5 parts by weight of copper oxide, 100 parts by weight of zeolite A and 40 parts of water
A part by weight was added and treated in the same manner as in Comparative Example 1 to prepare a paint. This coating material was applied to the surface of the glass tube of the same heating element as in Example 1 under the same application conditions, the deodorizing ability was evaluated, and the results are shown in Table 1.

Comparative Example 4 A coating material was prepared in the same manner as in Comparative Example 1 by adding 60 parts by weight of activated manganese dioxide (specific surface area: 256 m ² / g), 10 parts by weight of copper oxide, 50 parts by weight of zeolite A and 50 parts by weight of water. did. This coating material was applied to the surface of the glass tube of the same heating element as in Example 1 under the same application conditions, the deodorizing ability was evaluated, and the results are shown in Table 1.

[0026]

[Table 1]

From the results shown in Table 1, it was confirmed that the heating elements according to the examples exhibited a superior deodorizing effect as compared with the comparative examples.

Examples 4 to 11 The same active manganese dioxide, copper ion-supporting zeolite A and copper oxide as in Example 1 were blended in the proportions by weight shown in Table 2, and oxidatively decomposed and deodorized in the same manner as in Example 1. A paint for the catalyst was prepared.

[0029]

[Table 2]

Each of the prepared paints was applied to the surface of a glass tube of the same heating element as in Example 1 under the same application conditions, and the heating element was subjected to a deodorizing test of methyl mercaptan and trimethylamine by the following method. Table 3 shows the results. Methyl mercaptan deodorization test method: 500 × 500 × 5
The heating element of the example was installed in the center of a 00 mm acrylic plate, and the methyl mercaptan concentration in the sealed acrylic plate was adjusted to 20 ppm. Then, adsorption was performed at room temperature for 2 hours. The concentration at that time was measured with a gas tech detector tube, and the residual ratio was determined. Trimethylamine deodorization test method: A temperature controller was attached to the heating element of the example, and 500 × 500 × 500 mm
Installed in the center of the acrylic plate, connected to an external power supply,
Trimethylamine concentration in the sealed acrylic plate was 20
ppm, and adsorbed at room temperature for 2 hours. At that time, the concentration of trimethylamine was measured with a gas tech detector tube, and the residual ratio was determined. Then turn on the electric heater,
The temperature of the heating element is increased to 300 ⁰ C, the adsorbed amine is 1 hour oxidative decomposition, nitrogen monoxide at that time, the concentration of nitrogen dioxide was measured with Gastec detector tube, the proportion of nitrogen monoxide and nitrogen dioxide Examined.

[0031]

[Table 3]

From the results shown in Table 3, it was confirmed that the oxidatively decomposable deodorizing catalyst according to the present invention has an excellent deodorizing effect and can be regenerated by oxidative decomposition. Suitable range (active manganese dioxide:
Copper ion-supported zeolite: copper oxide = 1: 0.5 to 1:
0.05-0.5), the former tended to increase the residual ratio of methyl mercaptan, and the latter tended to increase the residual ratio of trimethylamine.

Example 12 A heating element obtained by applying the coating material of the oxidatively decomposable deodorizing catalyst prepared in Example 1 under the same conditions as described above was placed in a 10-liter gas collection bag, and methyl mercaptan in the gas collection bag was placed. The concentration was adjusted to 20 ppm. Thereafter, the concentration of methyl mercaptan in the gas collecting bag after 1 hour was measured with a gas tech detector tube. Then, the heating element is taken out, by energizing the electric heater, continued energization 30 minutes with raising the temperature of the heating element to 300 ⁰ C, and allowed to cool 30 minutes in the air and then stops energizing. The heating element was placed again in the 10-liter gas collection bag, and the concentration of trimethylamine in the gas collection bag was adjusted to 2%.
The concentration was adjusted to 0 ppm, and after one hour, the concentration of trimethylamine in the gas collecting bag was measured with a gas tech detector tube to determine the residual ratio. Next, energization and heat radiation were performed under the same conditions as described above. This experiment was repeated 20 times, and the results of such treatment are shown in Table 4.

According to the results shown in Table 4, the oxidatively decomposable deodorizing catalyst on the surface of the heating element easily oxidizes and decomposes the methyl mercaptan gas and the trimethylamine gas adsorbed thereon by the heat generated by an electric heater to change to an odorless gas. It was confirmed that the substance was desorbed, and no reduction in deodorizing ability due to repeated operations was observed. Therefore, it was confirmed that stable deodorizing ability can be maintained for a long period of time by oxidatively decomposing the adsorbed gas component, changing to an odorless gas, and desorbing.

[0035]

[Table 4]

Example 13 A heating element obtained by applying the coating material of the oxidatively decomposable deodorizing catalyst prepared in Example 1 under the same conditions as described above was placed in a clean 30-liter desiccator, and the electric heater was energized for 30 minutes. And allowed to cool in a desiccator for 30 minutes. Thereafter, methyl mercaptan was injected into the desiccator so as to have a concentration of 100 ppm, and after 30 minutes, the methyl mercaptan concentration in the desiccator was measured by gas chromatography (first example).
Times). Then, by energizing the electric heater, the methyl mercaptan concentration in the desiccator was continued energization 10 minutes with raising the temperature of the heating element up to 200 ⁰ C as measured by gas chromatograph (2nd measurement). Thereafter, the state in which the non-energized heating element was placed in the desiccator was maintained, and the concentration of methyl mercaptan after 30 minutes was measured by gas chromatography (third measurement). Also, instead of methyl mercaptan, a dimethyl sulfide concentration of 10
A similar test was performed at 0 ppm. Table 5 shows the measurement results of methyl mercaptan and dimethyl sulfide and the residual ratio.

[0037]

[Table 5]

From the results shown in Table 5, it was confirmed that the heat generated by the electric heater can exert an excellent deodorizing ability on methyl mercaptan and dimethyl sulfide.

[0039]

As described above, according to the present invention, the offensive odor gas which gives an unpleasant sensation can be efficiently adsorbed, and the adsorbed gas component is easily oxidized and decomposed and substantially removed by the heat generated by the heat generating member. In addition, it is possible to provide an inexpensive heating element that maintains stable high deodorizing ability for a long time. Therefore, by using this as a heating element for consumer electronics,
This makes it possible to deodorize the interior and surroundings of consumer electronics while generating heat.

[Brief description of the drawings]

FIG. 1 is a structural explanatory view of a heating element according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat generating member 2 Holding end 3 Casing 4 Oxidative decomposable deodorizing catalyst layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ identification code FI H05B 3/44 B01D 53/36 H (58) Field surveyed (Int.Cl. ⁶ , DB name) B01J 29/072 A61L 9 / 01 B01J 20/18 B01J 35/02

Claims (3)

(57) [Claims] 1. A casing comprising: a casing; and a heat generating member such as an electric resistance member disposed in the casing. The casing has an active manganese dioxide, a copper ion-supporting zeolite, and an oxide containing copper oxide as active components. A decomposable deodorizing catalyst is provided, and the activated manganese dioxide has a nitrogen adsorption ratio.
Porous dioxide with a surface area (BET) of 50 m2 / g or more
When it is manganese and represented by the general formula MnOX,
1.8 <x <2.0, and the activated manganese dioxide, zeolite supporting copper ions and copper
The composition ratio with the oxide is 1: 0.5 to 1: as a weight ratio.
Heat generation characterized by being in the range of 0.05 to 0.5
body. 2. The heating element according to claim 1 , wherein the active manganese dioxide is copper ion-loaded active manganese dioxide, the copper ion-loaded zeolite is copper ion-loaded zeolite A, and the copper oxide is copper oxide. Wherein oxidative decomposition deodorizing catalyst, without the paint forms formulated with at least inorganic binder, the oxidative decomposition of deodorizing catalysts of this paint form to claim 1 or 2, characterized in that applied to the surface of the casing Heating element as described.