JP3021301B2 - Antibacterial deodorant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antibacterial deodorizing material capable of removing a bad odor in a refrigerator or the like and preventing propagation of various bacteria.

[0002]

2. Description of the Related Art For example, in a refrigerator, various foods such as vegetables, fruits, fish and shellfish are stored in this closed small space. Therefore, various deodorizing materials have been conventionally used to remove odors generated from these foods.

[0003] As the deodorizing material, there are a built-in type which is built in a refrigerator in advance at a manufacturing stage, and a separate type which is stored in a refrigerator together with vegetables and fruits by a user. Recently, the former has been frequently used in terms of ease of handling.

[0004] A conventional deodorizing material or deodorizing device of this type, which is of a stationary type and is not replaced, is disclosed in JP-A-61-1.
Some of them use activated carbon disclosed in Japanese Patent No. 72561, and others use ozone disclosed in Japanese Utility Model Application Laid-Open Nos. 3-72289 and 3-73886. In the former, activated carbon known as an odor remover is applied for deodorization in a refrigerator, and in the latter, the decomposition of odor by ozone is used.

[0005] In particular, the former contains both activated carbon and solid acid so that malodors containing various odors can be effectively removed. Thereby, even a complex odor in which an acidic, neutral, and alkaline odor is mixed can be removed with a relatively high adsorptivity.

However, a deodorizing apparatus utilizing the decomposition action of ozone requires a high-pressure generator to generate ozone, which requires a large-scale apparatus, and requires an incorporation of an apparatus for removing ozone species. However, the device becomes complicated.

Further, the deodorization by activated carbon is mainly based on the adsorption action, and if the adsorption capacity is exceeded, there is a problem that the material of the activated carbon itself becomes a source of odor. In order to solve this problem, deodorizing materials mainly using catalysts have been developed, but various odors are generated in the refrigerator,
There is an odor that cannot be sufficiently removed by a deodorizing material mainly composed of this catalyst. In particular, the catalyst adsorbent can hardly remove methyl sulfide. Therefore, there is a strong demand for the development of a deodorizing material for refrigerators capable of removing methyl sulfide, which is a main component of odor in refrigerators, with high adsorption capacity.

Therefore, the present inventor has proposed Al ₂ O ₃ , SiO _2
2. A deodorant containing manganese oxide and copper oxide has been developed and has already been filed (JP-A-6-71168).

[0009]

However, the deodorant according to the prior application can remove methyl sulfide, which has been difficult up to now, but when it is built in a refrigerator in advance, it can be stored in the refrigerator. It has not yet reached the point of preventing the attachment of various bacteria from objects. For this reason, there is a demand for the development of an antibacterial deodorizing material capable of removing methyl sulfide with a high adsorptivity and preventing adhesion and propagation of various bacteria.

[0010] The present invention has been made in view of the above problems, and can remove various odors generated in a refrigerator, and particularly can remove methyl sulfide with high efficiency. It is an object of the present invention to provide an antibacterial deodorizing material capable of preventing adhesion and propagation of water.

[0011]

The antibacterial deodorizing material according to the present invention comprises 20 to 65% by weight of Al ₂ O ₃ , 5 to 55% by weight of SiO ₂ , 0.1 to 25% by weight of MgO, and manganese. The oxide is 5 to 50% by weight in terms of MnO, the copper oxide is 2 to 50% by weight in terms of CuO, and silver or a silver compound or a silver-containing substance is 0.005 to 1% in terms of Ag.
It is characterized by being constituted by a molded article containing 0% by weight.

In the present invention, instead of a molded product obtained by molding the material of the above-described component, a material having this component may be supported on a carrier.

In each case, the specific surface area of adsorption is 100
It is preferably from 300 to 300 m ² / g.

[0014]

In the present invention, as a main component of the deodorizing material,
By containing Al ₂ O ₃ , SiO ₂ , MgO, manganese oxide, copper oxide and silver or a silver compound or a silver-containing material, it is possible to remove even methyl sulfide which has been difficult to remove conventionally. At the same time, adhesion and propagation of various bacteria can be prevented, and these components are essential components for achieving the object of the present invention.

The reasons for limiting the numerical values of each component in the present invention will be described below.

Al ₂ O ₃ ; 20 to 65% by weight Al ₂ O ₃ is an essential component for securing the strength required as a molded article. When the content of Al ₂ O ₃ is less than 20% by weight, the effect cannot be expected, the strength becomes insufficient, and the powder is easily powdered. On the other hand, if the content of Al ₂ O ₃ exceeds 65% by weight, the content of the component having a catalytic action is relatively reduced, so that the deodorizing performance is reduced.

SiO ₂ : 5 to 55% by weight SiO ₂ is a component for improving the deodorizing performance. If the content of SiO ₂ is less than 5% by weight, its deodorizing effect cannot be expected, and in particular, the deodorizing performance of methyl sulfide and trimethylamine decreases.
If the content of SiO ₂ exceeds 55% by weight, the strength required as a molded product cannot be secured, and powdering tends to occur.

MgO: 0.1 to 25% by weight MgO is a component for improving antibacterial performance. When MgO is less than 0.1% by weight, the antibacterial effect cannot be expected. On the other hand, if the content of MgO exceeds 25% by weight, the strength required as a molded body cannot be secured, and powdering tends to occur. The preferable content ratio of this MgO is 0.1 to 5% by weight.
Range.

The amount of MgO is determined by confirming its effect by an antibacterial test in accordance with JIS Z 2911. This JIS rule is that the evaluation culture temperature condition is 28 ± 2 ° C.
It is. Considering that the temperature in the refrigerator is about 5 ° C., this condition is an extremely severe evaluation temperature condition. Therefore, the evaluation temperature was lowered according to the actual condition that the temperature in the refrigerator was about 5 ° C., and an evaluation culture test was performed at a temperature of 8 ± 2 ° C. to evaluate its antibacterial performance. Other conditions are JISZ291
According to 1. The reason why the temperature was set to 8 ± 2 ° C. instead of 5 ° C. was to take into account the rise in the internal temperature due to the opening and closing of the refrigerator.

As a result of evaluating the antibacterial property under the evaluation temperature of 8 ± 2 ° C., even if the content of MgO is relatively small,
It has been found that they exhibit sufficiently excellent antibacterial performance. Note that this also applies to the Ag content described later.

Manganese oxide: 5 to 5 in terms of MnO
0 wt% manganese oxide is a component that improves the deodorizing performance. In particular, by allowing the manganese oxide to coexist with the copper oxide, the adsorption ability can be significantly improved. When the amount of manganese oxide is less than 5% by weight in terms of MnO, the above deodorizing effect cannot be expected. When the content of manganese oxide is M
If it exceeds 50% by weight in terms of nO, the strength required as a molded body cannot be secured, and powdering tends to occur.

Copper oxide: 2 to 50 weight in terms of CuO
% Copper oxide is a component that improves deodorizing performance and antibacterial performance. In particular, by allowing this copper oxide to coexist with the manganese oxide, the ability to adsorb odor is significantly improved. When the amount of copper oxide is less than 2% by weight in terms of CuO, the above deodorizing effect and antibacterial effect cannot be expected. On the other hand, if the content of the copper oxide exceeds 50% by weight in terms of CuO, the strength required as a molded body cannot be secured, and powdering tends to occur.

Silver or a silver compound or a silver-containing material;
By adding 0.005 to 10% by weight of silver or a silver compound or a silver-containing material at the same time as MgO, they have an action of improving the antibacterial performance by a synergistic action of both. Silver or a silver compound or a silver-containing material is A
If the amount is less than 0.005% by weight in terms of g, the antibacterial effect cannot be expected. On the other hand, when the content of silver or silver compound is Ag
If it exceeds 10% by weight, the strength required as a molded body cannot be secured, and powdering tends to occur. Silver in the present invention may be metallic silver, silver oxide, silver chloride,
A poorly water-soluble compound such as silver sulfide, or a compound obtained by replacing silver with a cation of zeolite may be used. Considering antibacterial properties and economics, the preferable content of silver is 0.1.
The range is from 0.01 to 0.5% by weight.

Each of the above-mentioned components may be contained as a single oxide, or may be contained in the form of a composite oxide with other components. When contained in the form of a composite oxide, Al ₂ O ₃ , SiO ₂ , MgO, Mn
O, CuO, and Ag are respectively converted so as to fall within the range defined in the claims of the present application.

The main component of the deodorizing material for a refrigerator according to the present invention is the above 6
As for the components, a binder is used not only for simply mixing these components but also for forming a molded body. As the binder, there are an inorganic binder and an organic binder, but when an inorganic binder is used, the moldability is inferior. Therefore, it is preferable to use an organic binder.

The type of the organic binder is not particularly limited. Acid Ca, polyvinyl alcohol, polyacrylic acid ester, polymethacrylic acid ester, phenol resin, melanin resin and the like can be mentioned. In addition, an appropriate amount of an inorganic binder may be used in combination with the organic binder. Examples of the inorganic binder include colloidal silica, colloidal alumina, colloidal titanium, bentonite, sepiolite, and alumina phosphate.

The means for mixing and kneading the above six main components with a binder and the like are not particularly limited, and a known device may be used. In addition, the desired product can be obtained by molding the kneaded material into a predetermined shape, and drying and / or firing it according to a conventional method. However, methyl sulfide has a poor deodorizing ability in a dried product.

Further, regarding the molding shape, pellets,
Various shapes such as a bead shape, a ring shape, a honeycomb shape, and an accumulated mass of linear extrudates can be used.

Specific surface area: 100 to 300 m ² / g The specific surface area affects the deodorizing performance. Specific surface area of 100
By setting it to m ² / g or more, the deodorizing performance becomes particularly good. However, when the specific surface area exceeds 300 m ² / g, the strength as a molded body tends to decrease.

Therefore, the specific surface area is 100 to 300 m ² /
g is desirable. The specific surface area is a value measured by the BET method.

[0031]

Next, the results of a comparative test of the deodorizing performance of the deodorizing material according to the examples of the present invention with the comparative example will be described. Test Example 1 Four types of malodorous substances were selected: trimethylamine, methyl mercaptan, hydrogen sulfide, and methyl sulfide. Further, as shown in FIG. 1, a deodorizing material having a composition shown in Table 1 below was formed into a honeycomb shape, and the obtained honeycomb formed body 1 was formed.
Was set on the measuring jig 2 shown in FIG. However, in Table 1, No. 1 to No. 14 show comparative examples out of the scope of the present invention, and No. 15 to No. 25 are Examples of the present invention. In Examples 16 and 21, a Cu—Mn-based composite oxide was used as a MnO source and a CuO source.

[0032]

[Table 1]

[0033]

Next, each malodorous substance gas is allowed to flow through the measuring jig 2 at normal temperature and normal humidity, and the gas is collected at predetermined points of time at the point A on the entrance side and the point B on the exit side of the measuring jig 2. Then, the concentration of the collected gas was analyzed by gas chromatography, and the adsorption capacity of the deodorizing material was determined from the difference in concentration between the points A and B.
However, the inlet concentration was 20 ppm and the gas flow rate was 0.25 m /
Seconds. The measured value of the offensive odor substance adsorption capacity is the removal rate of the offensive odor substance after elapse of 20 minutes.

The compressive strength of each deodorizing material was measured by an Amsler universal testing machine as shown by an arrow P in FIG.
It was determined by measuring the compressive strength in the through-hole direction. However, when P is the maximum load and A is the test piece pressing cross-sectional area, the compressive strength σc is given by P / A.

Table 2 below shows the results of measuring the odorant-adsorbing ability and the compressive strength of each of the molded articles of Comparative Examples and Examples. In Table 2, the content of trimethylamine, methyl mercaptan and hydrogen sulfide was 80%.
If the above adsorption capacity and methyl sulfide have an adsorption capacity of 70% or more, and the compressive strength has a strength of 15 kg / cm2 or more, it is judged that both the adsorption capacity and the strength are excellent. This was represented by × or ○ in the overall evaluation column of No. 2.

[0037]

[Table 2]

[0038]

The antibacterial performance was evaluated according to JIS Z2911. That is, the culture temperature condition for evaluating the antibacterial performance was 8 ± 2.
° C and others were evaluated based on JIS Z2911.
The mold used in this antibacterial performance test is shown in Table 3 below.

[0040]

[Table 3]

Table 4 below shows a method of displaying test results according to JIS Z2911. In the present invention, in the column of antibacterial performance in Table 2, the case where the mold resistance is indicated as "3" is represented by "O", and the case where the mold resistance is 2 or less is represented by "X".

[0042]

[Table 4]

As shown in Tables 1 and 2, Comparative Example No. 1
Has a small amount of Al ₂ O ₃ , so that the strength of the compact is low. Comparative Example No. 2 contains too much Al ₂ O _{3 and} has relatively few other adsorbing components, so that the deodorizing performance of all deodorizing components is reduced. In Comparative Example No. 3, since the amount of SiO ₂ was small, the deodorizing ability of trimethylamine and methyl sulfide was reduced. In Comparative Example No. 4, since the amount of SiO ₂ was too large, the strength of the molded body was low. Comparative Example No. 5 has low antimicrobial performance because it contains less MgO. In Comparative Example No. 6, since the amount of MgO was too large, the strength of the compact was low. In Comparative Example No. 7, since the amount of manganese oxide was small, the deodorizing ability for methyl mercaptan and hydrogen sulfide during the deodorizing performance was reduced. Comparative Example N
In the case of o.8, since the amount of manganese oxide is too large, the strength of the molded body is small. In Comparative Example No. 9, since the amount of copper oxide was small, the deodorizing ability of methyl mercaptan and hydrogen sulfide during the deodorizing performance was low, and the antibacterial property was lowered. In Comparative Example No. 10, since the amount of copper oxide was too large, the strength of the molded body was low. Comparative Example N
In the case of o.11, the antibacterial property is low because Ag is small. In Comparative Example No. 12, since the amount of Ag was too large, the strength of the molded body was small. Since Comparative Example No. 13 has a small specific surface area, the deodorizing performance is generally reduced. In Comparative Example No. 14, since the specific surface area was too large, the strength of the molded body was reduced.

Since Examples No. 15 to No. 25 fall within the range defined in the claims of the present invention, all of the deodorizing performance, compressive strength and antibacterial performance against all offensive odor substances are good. is there.

Test Example 2 Next, the result of evaluating the antibacterial performance (mold resistance test) based on JISZ2911 will be described. That is, the evaluation culture temperature condition for antibacterial performance was set to 28 ± 2 in accordance with JIS regulations.
The odor removal performance, antibacterial performance, etc. were measured under the same conditions as in Test Example 1 except that the temperature was changed to ° C. The composition of the molded body subjected to the test is shown in Table 5 below, and the characteristics thereof are shown in Table 6.

[0046]

[Table 5]

[0047]

[0048]

[Table 6]

[0049]

Under severe conditions as in this test example,
As in the case of Test Example 1, the molded article of this example exhibits excellent antibacterial performance by increasing the amounts of Ag and MgO.

In this embodiment, since the deodorizing material is used at normal temperature, when the deodorizing material of the present invention is used in a refrigerator, the temperature becomes low. Performance can be obtained.

[0052]

According to the refrigerator deodorizing material of the present invention,
It has excellent adsorptive capacity against foul odors in refrigerators, and especially has excellent adsorptive capacity for methyl sulfide, which has been difficult to remove in the past, and also has excellent antibacterial performance.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a honeycomb formed body according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a measuring device for deodorizing efficiency.

[Explanation of symbols]

 1: Honeycomb molded body 2: Measurement jig

────────────────────────────────────────────────── (5) Continuation of the front page (51) Int.Cl. ⁷ Identification code FI A01N 59:00 59:16) (56) References JP-A-2-277455 (JP, A) JP-A-62-282637 (JP) JP-A-51-89890 (JP, A) JP-A-6-71168 (JP, A) JP-A-6-63393 (JP, A) JP-A-7-108168 (JP, A) 6-254140 (JP, A) JP-A-4-46106 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B01J 20/10 A01N 59/20 A61L 9/01

Claims (5)

(57) [Claims] 1. An Al ₂ O ₃ content of 20 to 65% by weight, SiO 2
₂ to 5 to 55% by weight, MgO to 0.1 to 25% by weight, manganese oxide to MnO to 5 to 50% by weight, copper oxide to CuO to 2 to 50% by weight, silver or When the silver compound or the silver-containing material is converted to Ag,
An antibacterial deodorizing material characterized by being formed from a molded article containing from 05 to 10% by weight. 2. A carrier comprising 20 to 65% by weight of Al ₂ O ₃ , 5 to 55% by weight of SiO ₂ , 0.1 to 25% by weight of MgO, and 5 to 5% by converting manganese oxide to MnO. A material containing 50% by weight, 2 to 50% by weight of copper oxide in terms of CuO, and 0.005 to 10% by weight of silver or a silver compound or a silver-containing material in terms of Ag. Antibacterial deodorizing material characterized by having. 3. Silver or silver compound or silver-containing material is Ag
The antibacterial deodorizing material according to claim 1, wherein the antibacterial deodorizing material is contained in an amount of 0.01 to 0.5% by weight in terms of conversion. 4. The antibacterial deodorizing material according to claim 1, comprising 0.1 to 5% by weight of MgO. 5. The antibacterial deodorizing material according to claim 1, wherein the specific surface area is 100 to 300 m ² / g.