JP2995453B2 - Antibacterial coating composition - 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 coating composition having improved antibacterial properties.

[0002]

2. Description of the Related Art Heretofore, paints obtained by adding an antibacterial agent to organic paint resins such as acrylic, epoxy, and urethane have been commercially available.

[0003] In this antibacterial paint, it is expected that the antibacterial agent will maintain sustained release over a long period of time.

[0004] However, when the antibacterial agent is coated on the organic resin, there is a problem that the antibacterial effect is unstable and hardly exerted.

[0005]

SUMMARY OF THE INVENTION Therefore, the present invention
An object of the present invention is to provide an antibacterial coating composition that can exhibit antibacterial properties more effectively than conventional ones.

[0006]

In order to solve the above-mentioned problems, the present invention employs the following technical means.

The antibacterial coating composition of the present invention contains an inorganic coating mainly composed of silica and a silane compound and an antibacterial agent, and is cured by heating after the coating of the coating. It is characterized in that continuous fine holes are formed therein.

That is, silica has a large surface area and is used as a matting agent for paints. However, an antibacterial agent is added to an inorganic paint containing this silica and a silane compound, and then heat-cured after the paint is applied. by finding a continuous to the fact that the sustained release of the antimicrobial agent is hardly difficult to antimicrobial is lost inhibited as micropores are formed in the coating film by, and have completed the present invention Things.

It is considered that the antibacterial property of the coating is hardly impaired because the inorganic coating containing silica fine particles easily forms a porous film and does not easily hinder the sustained release of the antibacterial agent. It is considered that the reason why the sustained release of the antibacterial agent is hindered when the antibacterial agent is added to the organic paint is that the coating property of the organic paint on the antibacterial agent is good.

[0010] The inorganic resin protects the member originally intended by the paint (for example, to prevent corrosion or damage) and exhibits excellent antibacterial properties by adding an antibacterial agent. Can be. That is, the antibacterial durability is excellent without impairing the decorative effect.

The above-mentioned fine silica powder or silica and / or colloidal silica dispersed in water or an organic solvent is incorporated into the composition at a content of about 30 to 60% by weight based on 100% by weight of the solid content of the composition. It can also be implemented as being done. If the amount is less than about 30% by weight, the antibacterial effect may be too small, and if it exceeds 60% by weight, cracks may occur, the smoothness of the coating film surface may be lost, or the adhesion may be reduced.

A silane compound represented by the general formula R ¹ _n Si (OR ² ) _4-n and / or a hydrolyzed general formula R ¹ _n
The silane compound represented by Si (OH) _4-n is contained in the composition in an amount of about 10 to 55% by weight based on 100% by weight of the solid content of the composition.
Can be carried out as if they were blended at a content rate of. If the amount is less than about 10% by weight, cracks may occur, the smoothness of the coating film surface may be lost, or the adhesion may be reduced. If the amount exceeds 55% by weight, the antibacterial effect may be too small.

A paint varnish containing an acrylic (methacrylic) resin and / or an epoxy resin or / and / or a urethane resin as a main component and containing a di- or trialkoxysilane group in an organic resin skeleton and used for coating is used as a composition. It can also be carried out as being incorporated in the composition at a content of about 10 to 45% by weight based on 100% by weight of the solid content of the composition. If the amount is less than about 10% by weight, cracks may occur, the smoothness of the coating film surface may be lost, or the adhesion may be reduced. If the amount exceeds 45% by weight, the antibacterial effect may be too small.

When the content of the antibacterial agent is 100% of the solid content in the composition.
It can also be carried out as about 0.1 to 50% by weight of the weight%. If the amount is less than about 0.1% by weight, the antibacterial effect may be too small. If the amount exceeds 50% by weight, cracks may occur, the smoothness of the coating film surface may be lost, or the adhesion may be reduced.

In general, the stronger the antibacterial agent is, the stronger the toxicity is recognized.
On the other hand, when a substance having extremely low toxicity is used, it is difficult to obtain necessary and stable antibacterial properties over a long period of time. Also, when a large amount of an antibacterial agent is added in order to bring out sufficient antibacterial properties, there is a tendency that the original performance of the paint such as the rust prevention effect and the aesthetic appearance of the decorative surface is impaired.

On the other hand, any commercially available antibacterial agent can be used for the antibacterial coating composition.
As described above, the antibacterial agent has a property that the sustained release property of the antibacterial agent is not easily inhibited, so that even a relatively weak antibacterial agent having a low toxicity can exhibit its antibacterial property sufficiently. That is, although a commercially available non-toxic and safe antibacterial agent is present in the coating film, it is possible to exhibit necessary and stable antibacterial properties.

The inorganic antibacterial resin coating can be widely applied to metals, glass, inorganic materials, etc., and can be coated with various materials. For example, building materials include stainless steel used in kitchens, wall materials, fittings used in bathrooms and toilets, wall materials, door handles and handrails used in public facilities such as hospitals, and medical facilities for public facilities. It can be used for various purposes such as various members, and improves its durability.

The function required of a building member to which a paint is to be applied tends to be judged not only from a sense of quality but also from a comprehensive viewpoint having safety and environmental hygiene. Although high technology has been established for building components from the aspect of decoration, improvement of sanitary technology has been delayed despite the wide range of public facilities. The antibacterial paint composition of the present invention can give sufficient durability and antibacterial action to the surface of a building member, with an emphasis on environmental hygiene required by society in the future.

The antibacterial coating composition of the present invention uses an inorganic coating resin exhibiting the most effective antibacterial properties. By using an inorganic resin as the coating resin, the antibacterial properties are not reduced. The advantage that safe antibacterial properties can be used in various applications at any added amount, and excellent antibacterial properties can be obtained with a very small amount of antibacterial agent compared to the case where an antibacterial agent is added to an organic paint. There is.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION As the colloidal silica, a commercially available water-dispersion type or alcohol solvent-dispersion type can be used. A coating resin may be synthesized from colloidal silica and a silane compound described in JP-B-52-39691. In addition to water and alcohol solvents, a dispersion liquid dispersed in an organic solvent that can be used as a solution of colloidal silica such as ethylene glycol monoalkyl ethers and propylene glycol alkyl ether acetates can also be used.

An organic resin containing a di- or trialkoxysilane group in the organic resin skeleton was obtained as follows.
One or more of acrylic (methacrylic) monomer and vinyl monomer and a silane compound having an unsaturated group, and the ratio of the monomer to the acrylic (methacrylic) monomer and vinyl monomer is The total amount of the silane compound is 5 to 100 parts by weight.
In an organic solvent (aromatic, acetate, alcohol, ketone, etc.) which is usually used at a resin concentration of about 30 to 60% by weight, an azo compound or a peroxide is used as an initiator. Polymerization was performed by a known method using an oxide or the like.

The above-mentioned organic resin is used in an amount of 1 to 30 based on 100 parts of the resin of the colloidal silica and the silane compound.
By mixing and dissolving in the range of parts, an inorganic coating material was obtained.

The antibacterial agent is not particularly limited as long as it can be easily dissolved or mixed and dispersed in the resin, and various commercially available antibacterial agents can be used. In addition, there are an organic compound and an inorganic compound as antibacterial agents. However, the inorganic resin is preferably a durable inorganic compound because the inorganic resin can protect the member to be coated without a decrease in its resistance over a long period of time.

The dispersing of the antibacterial agent in the inorganic coating material is performed by mechanical dispersing after dissolution or mixing. In this example, the antibacterial agent was added while stirring the paint using a general stirrer. The effect of the antibacterial agent is preferably about 0.1 to 40.0% by weight of the coating resin, but the effect and cost are considered to be about 0.5 to 10.
0% by weight is preferred.

[0025]

Next, the configuration of the present invention will be described more specifically. 1. Synthesis of Inorganic Resin The components were mixed in a flask according to Table 1 (parts by weight) and stirred at room temperature for 6 hours to obtain a hydrolyzate. When the pH of the obtained hydrolyzate was measured, it was 1-2. Aqueous ammonia diluted with water to 1 to 5% by weight was added dropwise to the hydrolyzate while adjusting the pH to a range of 4 to 6 to obtain an inorganic resin (Nos. 1 to 3). As the colloidal silica, an acidic type having a water dispersion type content of 20% by weight was used.

In the same manner as described above, the components were prepared according to Table 2 (parts by weight) and stirred at room temperature for 6 hours to obtain a hydrolyzate. The pH of the hydrolyzate was similarly adjusted to 4 to 6 using 1 to 5% by weight of aqueous ammonia (Nos. 4 to 6).
As the fine particle silica, a powder having a particle size of 1 to 5 microns was used.

Next, according to Table 3 (parts by weight), an acrylic resin to be added to the inorganic paint was polymerized. The polymerization was carried out by the following method. The monomer and the solvent were weighed in a four-necked flask, and after performing nitrogen replacement at room temperature for about 0.5 to 1.0 hour, the mixture was heated to 80 ° C. Therefore, the polymerization initiator is shown in Table 3.
And polymerized at 80 to 100 ° C. for about 5 to 6 hours (Nos. 7 to 9). As commercially available silicone-containing coating resins, the resins shown in Table 4 (resins manufactured by Shin-Etsu Silicone Co., Ltd.)
(Nos. 10 to 12).

Then, using the coating resins shown in Tables 1 to 4, weighing was performed in accordance with Tables 5 to 8, and the mixture was stirred at room temperature for 3 hours to obtain an inorganic coating. 2. Dispersion of antibacterial agent As shown in Tables 5 to 8, Examples 1 to 16 and Comparative Examples 1 to
An inorganic paint was obtained by changing the amount of the antibacterial agent added to the paint resin of No. 3. A high-speed stirrer was used for dispersing the antibacterial agent. Antibacterial agent is a commercially available product (Tovara Co., Ltd., trade name NOVALON AG300)
It was used. This antibacterial agent is of a silver compound type.

As a comparative example, an antibacterial agent was added to a commercially available organic paint (manufactured by Nippon Paint Co., Ltd., trade name: Acrose) and dispersed by the same method. (Example 1) 0.1 part by weight of an antibacterial agent was added to 100 parts by weight of the inorganic paint shown in Table 5, and the mixture was stirred for about 1 hour. After stirring,
It was confirmed that there was no aggregate, and an inorganic paint having antibacterial properties was obtained. (Example 2) Inorganic paint 1 shown in Table 5 as in Example 1
After adding 1.0 part by weight of the antibacterial agent to 00 parts by weight and stirring, an inorganic paint was obtained. (Example 3) Inorganic paint 1 shown in Table 5 as in Example 1
After adding 10.0 parts by weight of the antibacterial agent to 00 parts by weight and stirring, an inorganic paint was obtained. (Example 4) Inorganic paint 1 shown in Table 5 as in Example 1
50.0 parts by weight of the antibacterial agent was added to 00 parts by weight, and after stirring, an inorganic paint was obtained. (Examples 5 to 16) As in Example 1, 1.0 part by weight of an antibacterial agent was added to 100 parts by weight of each of the inorganic coatings shown in Tables 6 to 8, and after stirring, an inorganic coating was obtained. (Comparative Examples 1 to 4) Comparative Example 1 was prepared by adding and dispersing 0.1 part by weight of an antibacterial agent to an organic paint resin (trade name: Acrose, manufactured by Nippon Paint Co., Ltd.) in the same manner as in Example 1. Was added to and dispersed in 1.0 part by weight, Comparative Example 2 was obtained by adding 10.0 parts by weight of the antibacterial agent, and Comparative Example 4 was obtained by adding 50.0 parts by weight of the antimicrobial agent. 3. Preparation of test piece Aluminum plate, brass plate, stainless steel plate and marble were used as test pieces. Examples 1 to 16 and Comparative Example 1
Each of the test pieces was applied to each test piece by spraying, dried at 80 to 90 ° C for 5 minutes, and then heat-cured at 140 ° C for 15 minutes.

In addition, an inorganic building material such as a slate, a stone material, a concrete material or the like, glass, paper, non-woven fabric or the like may be used as a test piece. 4. Evaluation of antibacterial properties Differences in the antibacterial effects of the prepared test pieces were evaluated using cultured Escherichia coli, Staphylococcus aureus, and MRSA (methicillin-resistant Staphylococcus aureus). Antibacterial evaluation of Escherichia coli was performed using all kinds of test pieces, Staphylococcus aureus, MRSA
Was evaluated for two types of test pieces, an aluminum plate and a stainless plate. 5. Antibacterial test method Test piece (approx.
1 and inoculate the polyethylene film,
The cells were stored at 5 ° C., and after 6 hours and 24 hours, the surviving bacteria were washed out with SCDLP agar medium (manufactured by Nippon Pharmaceutical Co., Ltd.). The number of bacteria in the washed liquid was measured by an agar plate culture method (35 ° C., 2 days) using a culture medium for measuring the number of bacteria, and the number of viable bacteria per test piece was converted.

As a control, a petri dish was inoculated with the same amount of bacterial solution as that inoculated to the test piece, and the same test was performed.
The measurement at the start of storage was performed. The results are shown in Tables 9 to 14.

[0032]

[Table 1]

[0033]

[Table 2]

[0034]

[Table 3]

[0035]

[Table 4]

[0036]

[Table 5]

[0037]

[Table 6]

[0038]

[Table 7]

[0039]

[Table 8]

[0040]

[Table 9]

[0041]

[Table 10]

[0042]

[Table 11]

[0043]

[Table 12]

[0044]

[Table 13]

[0045]

[Table 14]

From the above results, it can be understood that when the antibacterial inorganic paint of this embodiment is applied to building members of various materials, it has superiority to commercially available antibacterial treated building members. You.

[0047]

The present invention is configured as described above and has the following effects.

It is possible to provide an antibacterial coating composition which can exhibit antibacterial properties more effectively than conventional ones.

Claims (5)

(57) [Claims] An inorganic paint containing silica and a silane compound as main components and an antibacterial agent, and added after the paint is applied.
An antimicrobial coating composition characterized in that continuous micropores are formed in the coating film by heat curing . 2. The composition according to claim 1, wherein the fine silica powder or the colloidal silica dispersed in water or an organic solvent is about 30 to 60% by weight based on 100% by weight of the solid content of the composition. The antibacterial coating composition according to claim 1, which is blended in the following. Wherein the general formula R ¹ _n Si (OR ²⁾ a silane compound represented by the _4-n or / and hydrolyzed formula R ¹
silane compounds represented by _n Si (OH) _4-n is from about 10 to 55 wt% of the formulation at a content according to claim 1 antibacterial described in the solid content 100 wt% of the composition in the composition Paint composition. 4. A paint varnish containing an acrylic (methacrylic) resin and / or an epoxy resin and / or a urethane resin as a main component, which contains a di- or trialkoxysilane group in an organic resin skeleton and is used for coating. The antibacterial coating composition according to any one of claims 1 to 3, wherein the antibacterial coating composition is incorporated in the composition at a content of about 10 to 45% by weight based on 100% by weight of the solid content of the composition. 5. The composition according to claim 1, wherein said antibacterial agent has a solid content of 10%.
The antibacterial coating composition according to any one of claims 1 to 4, which is about 0.1 to 50% by weight of 0% by weight.