JPH07108845B2 - Method for producing antibacterial agent - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing an antibacterial agent in which an antibacterial metal is supported on silica gel.

[0002]

2. Description of the Related Art At present, synthetic resin products are often used around kitchens, bathrooms and the like. However, bacteria are generated on the surface of these synthetic resin products, which is unsanitary,
There was also the problem of being unsightly. On the other hand, conventionally, a method has been used in which an antibacterial agent is mixed with a synthetic resin to prevent propagation of various bacteria. As the antibacterial agent to be mixed with the synthetic resin, an organic nitrogen-based antibacterial agent has been mainly used because it has a sufficiently strong antibacterial action even when mixed in the synthetic resin.

[0003]

However, the organic nitrogen-based antibacterial agent has a problem that the antibacterial action is too strong and has an adverse effect on the human body and the natural environment. On the other hand, when a safe antibacterial agent having a weak antibacterial effect is used, there is a problem that the antibacterial effect cannot be obtained unless the concentration of the antibacterial agent near the surface of the synthetic resin product is sufficiently high.

As described above, a safe antibacterial agent suitable for use by being mixed with a synthetic resin has not yet been developed. It is an object of the present application to solve the above problems and provide a method for producing an antibacterial agent, which is suitable for use by being mixed with a synthetic resin and has excellent safety.

[0005]

The method for producing an antibacterial agent of the present invention comprises the steps of immersing silica gel in a solution containing a silver complex salt,
A first step of supporting a silver complex salt on silica gel, and the first step
From the composition obtained in the step of using an evaporator
The solvent component is evaporated to remove it, and further vacuum dried.
And the composition obtained in the second step.
And a third step of applying a ring.

As the solution containing a silver complex salt, for example, a thiosulfato silver complex salt solution can be used. In addition, it is also possible to use a silver cyano complex salt solution, an ammine complex salt solution, or the like. The thiosulfato silver complex salt solution is prepared, for example, as follows. That is, pure water or ion-exchanged water 30
ml is heated to 40 ° C., 0.232 g of silver acetate is added thereto, and the mixture is stirred at 40 to 50 ° C. for about 5 minutes and then filtered to remove undissolved silver acetate. Alternatively, vigorous stirring may be performed until all the silver acetate is dissolved. 1.0 g of sodium sulfite is added as a stabilizer to the solution thus obtained with stirring. Add sodium sulfite and stir until the white cloudy solution becomes clear. Then sodium thiosulfate 0.6
Add 6 g and stir to give a thiosulfato silver complex salt solution.

To about 30 ml of the thiosulfato silver complex salt solution thus obtained, 5.0 g of silica gel having an average particle size of 10 μm or less was added, and the mixture was stirred for 10 minutes to support the silver complex salt on the silica gel. As the silica gel, for example, the product name “Cyroid # 55” (manufactured by Fuji Davison Chemical Co., Ltd.) or the like can be used, and the average particle size is 1 to 1.
It is preferably about 0 μm.

Thereafter, the mixture of the silver thiosulfato complex salt solution and silica gel is put in an evaporator to evaporate and remove the solvent component. As the evaporator, for example, under reduced pressure, like a rotary evaporator,
The one that can evaporate the solvent components while mixing the contents is suitable, and the product name is "Rotary evaporator RE4".
7 ”(made by Yamato Scientific Co., Ltd.) and the like are available. The solvent component is preferably removed at a temperature of about 50 to 70 ° C. at about 3000 Pa or less.

Thereafter, the obtained silica gel is further dried in vacuum. The same evaporator as described above can be used for vacuum drying, and it is preferably performed at a temperature of about 50 to 70 ° C. at about 3000 Pa or less. The silica gel supporting the silver complex salt thus obtained is coated. An organosilicon compound is suitable as a coating material, and for example, coating is performed as follows. First, 1 ml of ethyl alcohol and 1 ml of tetraethoxysilane (or tetramethoxysilane) are placed in a plastic container and stirred rapidly. 1 g of silica gel carrying a silver complex salt was added to this, and after stirring, 0.2 ml of pure water was added, and the mixture was boiled in water and heated at 60 ° C. for 30 minutes.
After stirring for 1 minute to complete hydrolysis of tetraethoxysilane, excess water and alcohol are evaporated by vacuum drying to obtain a silica-coated antibacterial agent.

Further, in the step of applying the coating, instead of immersing the silica gel in a solution containing an organosilicon compound and subjecting it to boiling water, excess water and alcohol are removed after the hydrolysis of tetraethoxysilane is completed. A silica coating may be applied by evaporating with an evaporator and further dried in vacuum. The same evaporator as described above can be used for silica coating and vacuum drying. Silica coating is about 30
It is preferable to carry out at a temperature of about 50 to 70 ° C. at about 00 Pa or less. Also, vacuum drying is preferably performed at a temperature of about 50 to 70 ° C. at about 3000 Pa or less.

[0011]

According to the method for producing an antibacterial agent of the present invention, after the silica gel is immersed in the silver complex salt solution, the solvent component is removed using an evaporator and the silver complex salt is supported on the silica gel. Almost all the silver complex salt can be supported on silica gel. Therefore, use solvent such as filter paper.
The amount of silver complex salt supported on silica gel can be increased as compared with the method of removing the components by filtration, and when used in a mixture with a synthetic resin, a sufficiently high concentration of silver complex salt on the surface of the synthetic resin, that is, An antibacterial component can be provided. Therefore,
Even if a silver complex salt having low toxicity is used as an antibacterial component, it is possible to produce an antibacterial agent which can obtain a sufficient antibacterial effect when mixed with a synthetic resin. It also carries a silver complex salt.
Since the silica gel is coated,
Coating prevents excessive release of silver complex salt
It Therefore, as described above, the supported amount of silver complex salt is large.
However, there is no meaningless release of excessive amount of silver complex salt,
If this antibacterial agent is mixed with a synthetic resin product and used,
Releases the silver complex salt near the surface of the synthetic resin product for a long time.
An excellent antibacterial effect can be obtained over time. Also, antibacterial ingredients
As it uses a silver complex salt with low toxicity as a
A fungicide can be manufactured.

[0012]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the description of the following examples unless it exceeds the gist. [Example 1] 60 ml of ion-exchanged water was heated to 40 ° C,
0.464 g of silver acetate is added thereto, and the mixture is stirred at 40 to 50 ° C. for about 5 minutes and then filtered through a filter paper (No. 2) to remove undissolved silver acetate. 2.0 g of sodium sulfite was added to the solution thus obtained with stirring. Sodium sulfite was added and stirred until the white and cloudy solution became transparent, then 1.32 g of sodium thiosulfate was added and stirred, and silica gel (Product name "Cyloid # 55": manufactured by Fuji Devison Chemical Co., Ltd.) Of 10.0 g was added and stirred for 10 minutes to support a silver complex salt on silica gel. After that, the mixture of this thiosulfato silver complex salt solution and silica gel is put in a rotary evaporator (product name “Rotary evaporator RE47”: manufactured by Yamato Scientific Co., Ltd.) to evaporate the solvent component at a temperature of 50 ° C. and about 3000 Pa or less. Removed. Then, the obtained silica gel was further vacuum-dried for 12 hours at a temperature of 50 ° C. and about 3000 Pa or less by a rotary evaporator.

The silica gel carrying the silver complex salt thus obtained was coated as follows. First, 10 ml of methyl alcohol, 10 ml of tetraethoxysilane, 10 g of silica gel carrying a silver complex salt and 0.2 ml of ion-exchanged water were put in a rotary evaporator to remove solvent components at a temperature of 50 ° C. and about 3000 Pa or less. Apply silica coating. The solidified product was vacuum-dried with a rotary evaporator at a temperature of 50 ° C. and about 3000 Pa or less for 12 hours to obtain an antibacterial agent. [Example 2] An antibacterial agent was obtained in the same manner as in Example 1 by using B-type silica gel (product name "Cyroid #B": manufactured by Fuji Davison Co., Ltd.) as silica gel. [Comparative Example 1] Using an aqueous solution in which 0.245 g of sodium sulfite and 0.163 g of sodium thiosulfate were dissolved,
A silica gel supporting a mixture of sodium sulfite and sodium thiosulfate was used as an antibacterial agent. [Measurement of MIC (Minimum Inhibitory Concentration)] Using the antibacterial agents of Examples 1 and 2 and Comparative Example 1 as samples, the minimum inhibitory concentration was measured by the following method. That is, the agar plate medium to which each sample was added at an arbitrary concentration was inoculated and cultured with the inoculum bacterial solution, and the minimum concentration of the growth-inhibited antibacterial agent was defined as the minimum inhibitory concentration of the sample against various microorganisms. The results are shown in Table 1.

However, the preparation of the agar plate medium, the preparation of the inoculum bacterial solution, and the culture were carried out as follows. -Preparation of agar plate medium With sterile purified water, 200,000 ppm, 100,
000ppm, 50,000ppm, 25,000pp
m, 12,500ppm, 6,250ppm, 3,13
0ppm, 1,560ppm, 780ppm, 390p
pm, 200ppm, 100ppm, 50ppm, 25
ppm, 12.5 ppm suspension was prepared. Next, each of the above suspensions was added to 1 / of the medium in a medium for sensitivity measurement [Mueller-Hinton agar medium (manufactured by DIFCO)] that became 50 to 60 ° C. after dissolution.
After adding 9 volumes and thoroughly mixing, the mixture was divided into a petri dish and solidified to obtain an agar plate medium.・ Preparation of bacterial solution for inoculation Enrichment medium [Mueller Hinton Broth (Muel
Ler-Hinton Broth (manufactured by DIFCO)], the bacterial solution of the test strain that had been cultured overnight at 35 ° C. was diluted with the same medium so that the number of bacteria per ml was about 10 ⁶ . However, the following strains were used as test strains.

E. coli: Escherichia coli (Esc
herichia coli) IFO 3301] Staphylococcus aureus: Staphylococcus aureus (S
taphylococcus aureus) 127
32. Culturing The bacterial solution for inoculation was smeared on an agar plate medium with a nichrome wire loop (internal diameter of about 1 mm) for about 2 cm, and cultured at 35 ° C. for 1 day.

[0016]

[Table 1]

As is apparent from Table 1, Examples 1 and 2
In the agar plate medium containing the antibacterial agent of Comparative Example 1, even though a low-toxicity silver complex salt is used as the antibacterial component, the concentration is much lower than that of the agar plate medium containing the antibacterial agent of Comparative Example 1. It was possible to prevent the growth of bacteria. [Antifungal Antibacterial Test of Synthetic Resin Mixture] The antibacterial agent produced in the above Examples 1 and 2 was added to the unsaturated polyester resin at the time of molding.
Molding was carried out by uniformly mixing and dispersing 5 parts by weight of the antibacterial agent with 100 parts by weight of the resin. On the other hand, as Comparative Example 2, a resin containing no antibacterial agent was molded.

The following synthetic antibacterial and antibacterial tests were carried out on the synthetic resin moldings containing the antibacterial agents of Examples 1 and 2 and the synthetic resin molding of Comparative Example 2. The results are shown in Table 2.・ Antifungal test Mold resistance test of Japanese Industrial Standard (JIS Z 291
The test was carried out according to the halo test method by the mildew proof test for textiles of 1). The mold used was Cladosporium clado.
sporioides), ketomium globosum (C
haetomium globosum, Penicillium citrinum (Penicillium citri)
num), Aspergillus niger
lus niger). Evaluation was carried out 14 days later. -Antibacterial test The antibacterial test was carried out according to the above hello test method. The fungus is Escherichia col
i), Staphylococcus aureus (Staphy)
lococcus aureus) and Bacillus subtilis (Bacillus subtilis) were used. Evaluation was carried out after 7 days.

[0019]

[Table 2]

As is apparent from Table 2, Examples 1 and 2
The synthetic resin molded article containing the antibacterial agent is excellent in the ability to suppress the generation of mold and fungi on the surface of the synthetic resin, as compared with Comparative Example 2 in which the antibacterial agent is not mixed. Further, the thiosulfato silver complex salt was added so that the silver component was the same as in Examples 1 and 2,
When blended alone in the above synthetic resin and observed the change over time, Examples 1 and 2 exhibited an antifungal and antibacterial effect for a longer period of time.

As described above, the antibacterial agents produced in Examples 1 and 2 have excellent antibacterial effect. Moreover, when mixed with a synthetic resin and molded, it has an excellent effect of suppressing the growth of mold and fungi on the surface of the synthetic resin molded product. Further, since the solvent component is removed by using an evaporator instead of filtering the silica gel from the silver complex salt solution, the amount of the silver complex salt supported on the silica gel can be accurately adjusted by the concentration of the silver complex salt solution. In addition, compared to the method of filtering, there is no waste of unnecessary silver complex salt solution,
It is convenient in the manufacturing process.

The antibacterial agents produced in Examples 1 and 2 may be mixed with a synthetic resin molded product or may be mixed with a coating material and applied to the surface of stainless steel or the like.

[0023]

As described above, according to the present invention,
It is possible to provide a method for producing an antibacterial agent which is suitable for being mixed with a synthetic resin and which is excellent in safety. In particular, the product of the present invention
According to the manufacturing method, the solvent component is vaporized using an evaporator.
Since it is emitted and removed, it is possible to remove the solvent component by filtration.
The amount of silver complex salt supported on silica gel
Can be increased, and the coating
Release of excess silver complex salt is suppressed,
It has an excellent effect of obtaining an antibacterial effect.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Atsushi Nishino 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Kazuhiko Yaguchi, 2846 Kozoji Town, Kasugai City, Aichi Prefecture (72) Inventor Kozo Yamamoto 2-1846 Kozoji-cho, Kasugai-shi, Aichi Fuji-Davison Chemical Co., Ltd. (56) References JP-A-2-292201 (JP, A) JP-A-1-283204 (JP, A )

Claims (2)

[Claims] 1. A by immersing the silica gel in a solution containing silver complex, a first step of Ru is supported silver complex salt to silica gel
Then, the solvent component is removed from the composition obtained in the first step by using an evaporator, followed by vacuum drying .
A second step, the composition obtained in the second step, the manufacturing method of the antimicrobial agent characterized by comprising a third step of applying a coating. 2. The third step is the second step.
The obtained composition is immersed in a solution containing an organosilicon compound.
2. The method for producing an antibacterial agent according to claim 1, which comprises a step of dipping, then applying a silica coating by removing a solvent component using an evaporator, and further vacuum drying.