JP3154362B2 - Antibacterial coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an antimicrobial coating.

[0002]

2. Description of the Related Art In recent years, when synthetic resin products are frequently used, or when used in a field that requires attention to hygiene such as kitchen utensils, contamination of the surface of the synthetic resin by bacteria is a problem. It is becoming. In addition, there are problems such as fungi and mold growing on the surface of the caulking material used as a building material, resulting in hygiene or poor appearance. As a countermeasure, a method has been used in which an antibacterial composition is mixed into a synthetic resin and the composition is eluted on the surface of the synthetic resin to sterilize the resin surface. As an antibacterial material used for this kind of purpose, an organic antibacterial antifungal material such as thiabendazole is known.

[0003]

Since the above-mentioned organic antibacterial and antifungal material has volatility, if it is contained in a synthetic resin, the surrounding environment of the synthetic resin is contaminated and the surface of the synthetic resin comes into contact with the surface. The discharged wastewater contains an antibacterial and antifungal material, which causes pollution of the wastewater environment, and further has a problem of affecting activated sludge during sewage treatment. Recently, there has been an increasing interest in hygiene, and it is desired that antibacterial properties be imparted to the surfaces of objects in contact with humans, such as door knobs. However, a molded article of a synthetic resin mixed with an antibacterial material as described above has a limit in durability performance, and is not easy to apply to various objects.

Accordingly, it is an object of the present invention to provide an antibacterial coating which can be easily applied to the surface of various objects and can be easily renewed when the antibacterial performance is reduced. Another object of the present invention is to provide an antibacterial coating that does not contaminate the surrounding environment.

[0005]

The antibacterial coating of the present invention comprises:
Porosity of silica gel particles etc. as antibacterial agent in release coating
It is obtained by dispersing a silver thiosulfato complex supported on particles . Further, the antibacterial coating of the present invention has a porous particle in a coating soluble in a specific solvent such as an acidic or alkaline aqueous solution such as warm water, alcohol, petroleum organic solvent, and acetic acid.
Is obtained by dispersing a thiosulfatosilver complex supported on a substrate .

The antibacterial complex comprising the silver thiosulfato complex and the porous particle carrier is prepared by dissolving a silver salt, for example, silver acetate, in water and adding sodium sulfite and sodium thiosulfate or a combination of potassium sulfite and potassium thiosulfate to the solution. Are sequentially added to form a silver thiosulfato complex solution, and then a particle carrier is added, the carrier is impregnated with the silver thiosulfato complex solution, and dried. Further, it is desirable that the outer surface of this complex is formed with an outer shell coating layer of silicon dioxide formed by hydrolyzing a sol-gel solution composed of alcohol and alkoxysilane on the outer surface. As the carrier, silica gel is preferable, but zeolite, montmorillonite and the like can also be used. As the alcohol, methanol, ethanol or propanol is preferably used. Further, as the alkoxysilane, the alkyl group has 1 carbon atom.
It is preferable to use the alkoxysilanes of (1) to (4).

[0007]

The film in which the antibacterial agent of the present invention is dispersed is releasable or soluble in a specific solvent. Therefore, if the antibacterial performance is reduced, it is removed by dissolution or dissolution and replaced with a new antibacterial film. Can be. Therefore, it can be easily applied to the surface of a living environment such as a door knob. Then, the bacteria and the like adhering to the surface can be inactivated, and the bacteria and the like passing through human hands can be reduced.

[0008] When the above-mentioned silver thiosulfato complex complex is used as an antibacterial agent, it does not form water-insoluble silver chloride even in the presence of chloride ions, and exhibits a stable antibacterial and antiviral effect. Further, even if this silver salt is eluted from the film, it hardly causes environmental pollution. In addition, this complex
By coating at least a part of the coating material with the above-mentioned coating material such as silicon dioxide, it is possible to make the silver salt sustained release and to improve the light stability.

[0009]

Embodiments of the present invention will be described below. First, the manufacturing process of the silver thiosulfato complex complex used in the present invention will be described. Since CH ₃ COOAg as a raw material has a low solubility, 7.7 g / l, which is close to the solubility, is converted to chlorine-free water at a temperature of 60 ° C. or less. Dissolve. In this melting step, the temperature is 6
If the temperature exceeds 0 ° C., CH ₃ COOAg is decomposed.
Hereinafter, the range of room temperature is preferable. Next, for example, S ₂ O ₃ -Ag
Na ₂ SO ₃ .7H ₂ O: CH ₃ C so that a stoichiometric amount of sodium sulfite is added so that a complex of —S ₂ O ₃ is formed.
OOAg = 4.3 g: added so as to have a ratio of 1 g,
After sufficient dissolution, sodium thiosulfate was added to Na ₂ S ₂ O
_{3 · 5H 2 O: CH 3} COOAg = 2.8g: was added at a ratio of 1g, dissolved. The temperature at this time is 40
C. to room temperature are preferred. Here, Na ₂ SO ₃ .7H ₂
Although a combination of O and Na ₂ S ₂ O ₃ .5H ₂ O was used, a combination of K ₂ SO ₃ and K ₂ S ₂ O ₃ may be used instead. Next, in the adsorption step, a solution of the thiosulfato complex salt is sufficiently adsorbed and impregnated on the carrier to a desired concentration using a porous carrier having a desired particle size such as silica gel. This step preferably has a temperature range of 40 ° C. to room temperature. Next, in the drying step, the pressure is preferably normal pressure to 10 ⁻² Torr, and the temperature is preferably 120 to 40 ° C. so that the thiosulfato complex salt is not decomposed.

Next, the formation of the outer shell coating layer by the sol-gel method adjusts the duration of the pharmacological effect when the thiosulfato complex salt is used as an antibacterial agent or a virus inhibitor.
The purpose is to change the immediate release to sustained release to improve the sustainability of the drug effect. For this reason, it is preferable to select the alcohol and the alkoxysilane from those described above in consideration of the use and economy. Here, the ethyl alcohol system of the standard formulation is described. Ethyl alcohol and tetraethoxysilane (CH ₃ CH ₂ O) ₄ Si were added to 1 g of the carrier supporting the silver thiosulfato complex salt for 1 m each.
g. The temperature is preferably from 40 ° C. to room temperature. Next, in the drying step, the pressure is preferably normal pressure to 10 ^-2 Torr, and the temperature is preferably 120 ° C to 40 ° C so that the silver thiosulfato complex salt is not decomposed.

Example 1 1% by weight of the antibacterial composite prepared by the above method was kneaded in a polyvinyl butyral resin, and a coating having the following composition was prepared by adjusting the viscosity to an appropriate value using alcohol as a solvent. B. Polyvinyl butyral 22.5 parts by weight (degree of polymerization: about 300) Methanol 4.5 parts by weight Ethanol 59 parts by weight Castor oil 4 parts by weight O. P 4 parts by weight Alkyl phosphate ester salt 2 parts by weight UV absorber 0.5 part by weight Whitening inhibitor 2.5 parts by weight Antistatic agent 1 part by weight This paint is applied to a metal knob of a door, and naturally applied for about 1 hour. After drying, a film having a thickness of about 100 μm was obtained. This coating was durable for about one month under normal use conditions. 1
After one month, a cut was made in one place of the coating, and the coating was peeled off from the door knob. Thereafter, the same antibacterial film as described above was formed again and put to practical use.

Next, the function and effect of the antibacterial coating of the present invention will be described. Since the antibacterial composite prepared by the above-described method is mixed as an antibacterial agent component in the antibacterial film, the antibacterial agent present on the surface of the antibacterial film exhibits antibacterial performance on the surface. In other words, when the germ is touched by a hand or the like with germs, even if the germs on the hand surface are transferred together with germ-free germ components such as sebum on the hand surface, the growth on the pellicle is suppressed. However, the antibacterial agent component is gradually removed from the film by transfer or the like while exhibiting the above effects, and the antibacterial performance is reduced. In addition, the coating itself is worn and damaged. Therefore, when the durability of the film is reduced, the effect can be updated by peeling and removing the film and forming a new film again. Especially as an antibacterial agent,
The use of the antibacterial complex by the above-mentioned manufacturing method,
No decrease in antibacterial performance when coexisting with chlorine-containing materials such as chlorine-based detergents, which are widely used as disinfectants for general goods, and activator against membrane viruses causing influenza, AIDS, etc. And that it has anti-MRSA properties.

Next, an experiment for confirming the antibacterial effect, antifungal effect, anti-MRSA effect and antiviral effect of the antibacterial coating of the present invention was carried out as follows. Table 1 shows the results. Anti-mold test: Mold resistance test according to Japanese Industrial Standards (JIS
Z 2911) according to the halo test method based on an antifungal test for textile products. The mold used was Cladosporium cladosporoides,
These are Chaetomium globosum, Penicillium citrinum and Asperigillus niger. Evaluation was performed 14 days later. Antibacterial test: Escherichia cole
i), Staphylococcus aureus
s aureus) and Bacillus subtilli
s) and according to the drop test method. The evaluation was performed after 7 days. In the drop test, a preculture is performed, about 10 ⁵ CFU / ml solution of bacteria in the logarithmic growth phase is dropped on the test piece, and the culture is performed for 18 hours at 35 ° C. in an atmosphere. Collect this culture,
It measures the number of bacteria surviving there.

[0014]

[Table 1]

From Table 1, it can be seen that the coating of this embodiment has practical antibacterial and antifungal properties. On the other hand, as a control, an aqueous solution of silver acetate as a starting material is prepared. This is not particularly limited to silver acetate, and any type of silver salt such as silver nitrate can be used. Table 1 shows the results of virus suppression experiments, in which a substance obtained by adsorbing and supporting this on silica gel and forming a coating in the same manner as in Example 1 as an antibacterial material is shown as a control, and the results are shown in Table 1. found. Also, a step of producing a silver thiosulfato complex complex of the present invention,
A composite is prepared by the same method except that silver acetate as a starting material is not added. Table 1 shows the results of virus suppression experiments in which this composite was used as an antibacterial material to form a coating in the same manner as in Example 1 as a comparative example. Thus, those containing no silver thiosulfato complex have no antiviral inhibitory effect. Next, the physical properties of the coating were examined. Size 10c
Using a polypropylene resin plate having a size of mx 10 cm and a thickness of 3 mm, the paint prepared by the above method was applied to one surface of the plate by spraying so as to have a thickness of about 100 µm, and then dried at room temperature. There is no problem with the ease of application of the paint, and the drying time is 20
A minute was enough. Further, the smoothness of the obtained coating film was good, and the oil resistance was almost unchanged for 4 months.

Example 2 A paint having the following composition was prepared. Melting point 125 ° F Paraffin 100 parts by weight Oxidized paraffin OX450 110 parts by weight (Nippon Wax KK, melting point 57 ° C., oxygen content 8.8%) Triethanolamine 16.5 parts by weight Water 420 parts by weight The above-mentioned composition is heated and stirred. After that, the emulsion sufficiently emulsified using a homogenizer was subjected to the experiment.

This paint was applied to a doorknob and air-dried for about 1 hour to obtain a resin film having a thickness of about 100 μm. This coating was durable for about one month under normal use conditions. One month later, the coating was immersed in warm water, and the coating was peeled off from the door knob. Thereafter, the same antibacterial film as described above was formed again and put to practical use. About this antibacterial coating,
The same antibacterial, antifungal, anti-MRSA, and antiviral effects as in Example 1 were confirmed. Also, as long as it does not affect the antibacterial agent, change the resin and solvent of the paint,
After the formation of the film, it is also possible to obtain a film soluble in a specific solvent such as an acidic or alkaline aqueous solution such as an alcohol, a petroleum organic solvent, and acetic acid.

[0018]

As described above, the present invention can be applied to the surface of various objects, and when the antibacterial performance is deteriorated, it can be removed by peeling or dissolving and easily changed to a new one. It provides a coating. In addition, by using silver thiosulfato complex as an antibacterial agent, an antibacterial coating which hardly causes environmental pollution and has an antiviral effect can be obtained.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Shuji Nakayama 1006 Kazuma Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-6-154242 (JP, A) JP-A-6-154 218029 (JP, A) JP-A-5-146370 (JP, A) JP-A-7-97317 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A01N 59/16 A01N 25 / 08 A01N 25/34

Claims (2)

(57) [Claims] 1. A method in which a porous particle is supported in a peelable film.
Antibacterial coating comprising dispersed silver thiosulfato complex . 2. A porous film which is soluble in a specific solvent .
An antibacterial coating formed by dispersing a silver thiosulfato complex supported on particles .