JP2000303000A - Antimicrobial, mildewproof and highly hydrophilic coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antimicrobial, mildewproof and highly hydrophilic coating material excellent in antimicrobial property, mildewproof property, highly hydrophilic property and heat resistance, capable of forming coated film excellent in coated film strength and not causing the abrasion of a mold, a working tool, etc., used for the processing of a metal plate such as aluminum plate having the above coated film on its surface. SOLUTION: This coating material comprises at least (A) an antimicrobial and mildewproof agent where a reaction product of an antimicrobial metal ingredient with a mildewproof organic compound was made to adhere to the surface and/or inside of porous silica particles and (B) a hydrophilic resin. The coating material may comprise at least (A) an antimicrobial and mildewproof agent where a reaction product of an antimicrobial metal ingredient with a mildewproof organic compound was included in porous silica and (B) a hydrophilic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antibacterial / antifungal / highly hydrophilic coating suitable for forming a high-grade antibacterial / antifungal / highly hydrophilic coating on the fin surface of a heat exchanger for air conditioning. .

[0002]

2. Description of the Related Art Generally, a heat exchanger is a room air conditioner,
It is used in various fields, such as package air conditioners, cool storage showcases, refrigerators, and dehumidifiers. As the fin material for the heat exchanger, aluminum or aluminum alloy having excellent workability and heat conductivity is widely used.

[0003] On the surface of the fin material for heat exchangers, dew condensation generated during cooling becomes water droplets and accumulates in gaps between the fins, increasing ventilation resistance and reducing heat exchange efficiency. Surface treatment for imparting water repellency or hydrophilicity has been carried out in order to increase the water repellency or hydrophilicity.

[0004] However, if the effect of the coating material for imparting water repellency or hydrophilicity to the aluminum or aluminum alloy surface is not sufficient, water droplets condensed in the gaps between the fins at the time of air blowing cause a phenomenon of fog. Especially in the case of an air conditioner equipped with a heat exchanger in the indoor unit, if various germs and fungi are breeding in the water droplets, the indoor environment is polluted,
Causes allergies and infections.

[0005] For this reason, it is required that the heat exchanger, especially the fin portion, be subjected to an antibacterial and fungicide treatment. An appropriate amount of the agent is blended, and an antibacterial and antifungal treatment is applied.

[Problems] A conventional air conditioner having a heat exchanger subjected to an antibacterial and fungicide treatment in an indoor unit has the following problems. That is, the thickness of the coating film on the surface of the aluminum or aluminum alloy fin is as thin as about 1 μm, and when a paint containing an inorganic silver-based antibacterial agent is used, the particle size of the antibacterial agent is 0.6 to 5 μm. Therefore, the strength of the coating film may be impaired. Further, when an aluminum or aluminum alloy plate pre-coated with the paint is formed into a fin, since the inorganic silver-based antibacterial agent having a large particle diameter is compounded, abrasion of a mold used for the processing, a processing tool, and the like is reduced. It becomes intense. In addition, when an organic fungicide is used, many preparations elute or volatilize, so that they flow into the drainage path together with the condensed water droplets, and may adversely affect the surface of the plastic drain pan such as deterioration or cracking. Furthermore, when water droplets containing such an organic fungicide are discharged into a room in the form of a mist, chemical substance sensitivity or the like due to volatile organic compounds may occur. In addition, since the organic fungicide lacks heat resistance, after passing through a drying and baking step for forming a coating film generally performed at 200 to 300 ° C., the residual ratio of the organic fungicide decreases, and Is extremely low.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and specific problems to be solved for it are antibacterial property, antifungal property,
A mold that is capable of forming a coating with excellent hydrophilicity and heat resistance, as well as excellent coating strength, and that has a coating on the surface, such as an aluminum plate, for processing a metal plate. An object of the present invention is to provide an antibacterial / antifungal / highly hydrophilic paint which does not wear tools and the like.

[0008]

This problem can be solved by the following antibacterial, antifungal and highly hydrophilic paints. That is,

The antibacterial / antifungal / highly hydrophilic paint according to the first aspect of the present invention provides an antimicrobial / antifungal / hydrophilic paint in which a reaction product of an antibacterial metal component and an antifungal organic compound is fixed on the surface and / or inside of porous silica particles. It is characterized by containing at least a fungicide and a hydrophilic resin.

Alternatively, the antibacterial / antifungal / highly hydrophilic paint according to claim 2 is an antibacterial / antifungal agent in which a reaction product of an antibacterial metal component and an antifungal organic compound is encapsulated by porous silica. And at least a hydrophilic resin.

Here, as in the antibacterial / antifungal / highly hydrophilic paint according to claim 3, the antifungal organic compound is an imidazole compound, a thiazole compound, an N-haloalkylthio compound, a pyridine compound, It is preferably at least one selected from the group consisting of isothiazolone compounds.

Further, as in the antibacterial / antifungal / highly hydrophilic paint according to claim 4, the antibacterial / antifungal agent has a particle diameter of 0.01 to 1%.
μm is preferred.

[0013]

Embodiments of the present invention will be described below in detail. However, this embodiment is specifically described for better understanding of the gist of the present invention, and does not limit the present invention unless otherwise specified.

"First antibacterial / antifungal / highly hydrophilic paint" The first antibacterial / antifungal / highly hydrophilic paint in the present embodiment is a reaction product of an antibacterial metal component and an antifungal organic compound. The product contains at least an antibacterial and fungicide (hereinafter referred to as a "first antibacterial and fungicide") fixed on the surface and / or inside of the porous silica particles, and a hydrophilic resin.

The first antibacterial / antifungal / highly hydrophilic paint contains a first antifungal / antifungal agent, and this first antifungal / antifungal agent combines an antibacterial component and an antifungal component. Since it has a heat resistance of about 300 ° C., the resulting coating film exhibits excellent effects on both antibacterial properties and antifungal properties, and also has excellent heat resistance. Furthermore, since the first antibacterial / antifungal / highly hydrophilic paint contains a hydrophilic paint such as a water-soluble resin or a water-dispersible resin, high hydrophilicity is exhibited.

The first antibacterial and antifungal agent is a product in which a reaction product of an antibacterial metal component and an antifungal organic compound is fixed in the network structure of silica and at the structural end. The state of the reaction product of the antibacterial metal component and the antifungal organic compound fixed in the network structure of the silica and at the structural end is not always clear, but as shown in FIGS. Silicate group (Si-
It is presumed that they are bonded via O-).

In the first antibacterial and antifungal agent, the antibacterial metal component is not particularly limited. For example, silver, copper, zinc and the like are used from the viewpoint of safety, antibacterial property and the like.
Particularly, silver is preferably used.

The antifungal organic compound is not particularly limited as long as it reacts with the antibacterial metal component to form a product. From the viewpoint, for example, imidazole compounds such as 2- (4-thiazolyl) -benzimidazole (hereinafter abbreviated as TBZ), thiazole compounds, N-haloalkylthio compounds such as N- (fluorodichloromethylthio) -phthalimide, Pyridine compounds such as 2,3,5,6-tetrachloro-4- (methylsulfonyl) -pyridine;
Isothiazolone compounds such as 1,2-benzisothiazolone and the like are used. In particular, those which can become an organic ligand to an antibacterial metal component such as TBZ are preferably used.

The content of the reaction product between the antibacterial metal component and the antifungal organic compound in the first antibacterial and antifungal agent depends on the antimicrobial and antifungal effect and the antimicrobial and antifungal effect. It is desirably 0.01 to 20% by weight, and preferably 1 to 10% by weight, from the viewpoint of the durability. If the content is less than 0.01% by weight, the manifestation of the antibacterial and antifungal effects becomes uncertain,
If the content exceeds 20% by weight, the content of the antibacterial and antifungal component becomes excessive, which leads to an unnecessary increase in raw material costs.

The particle size of the first antibacterial and antifungal agent is 0.0
It is preferably from 1 to 1 μm. If the particle diameter is smaller than 0.01 μm, remarkable secondary aggregation may occur, and dispersion may be difficult. On the other hand, if the particle diameter is larger than 1 μm, gold used for processing a plate material such as an aluminum plate having a dried and cured coating on the surface. In addition to the abrasion of the mold and the processing tool, there is a possibility that the adhesion to the coated substrate, the smoothness of the coating film, and the strength of the coating film may be impaired. This first antibacterial and antifungal agent is disclosed in, for example,
It can be produced by the method described in JP-A-194292.

The hydrophilic resin forms a hydrophilic coating such as a water-soluble resin or a water-dispersible resin, and holds the first antibacterial and fungicide in the coating. Specific examples include one or a mixture of two or more hydrophilic resins such as an acrylic resin, a polyurethane resin, a polyester resin, a polyamide resin, an epoxy resin, a cellulose resin, and a polyether polyol resin.

In the first antibacterial / antifungal / highly hydrophilic paint, the first antibacterial / antifungal agent is contained in a solid content of 0.01 to 10%.
Desirably, it is contained by weight. If the amount is less than 0.01% by weight, sufficient antibacterial and antifungal properties and its sustainability cannot be obtained. Incorporation increases the cost, and the content of the hydrophilic resin is relatively reduced, resulting in insufficient hydrophilicity.

Further, the first antibacterial / antifungal / highly hydrophilic paint has, as other components, a surfactant for improving dispersibility, an antifoaming agent, and a coloring for coloring a coating film. Agent,
An appropriate amount of various solvents such as alcohol, cellosolve, and ketone for adjusting the drying state may be blended.

"Second antibacterial / antifungal / highly hydrophilic paint"
Examples of the antibacterial / antifungal / highly hydrophilic paint include antibacterial / antifungal agents in which a reaction product of an antibacterial metal component and an antifungal organic compound is encapsulated by porous silica (hereinafter referred to as “second antibacterial / antifungal agent”). Agent
Called. ) And a hydrophilic resin.

The second antibacterial / antifungal / highly hydrophilic paint contains the second antifungal and antifungal agent therein, and the second antifungal and antifungal agent comprises an antibacterial component and an antifungal component. About 300 ℃
Since it has a certain level of heat resistance, the resulting coating film exhibits excellent effects on both antibacterial properties and antifungal properties, and also has excellent heat resistance. Furthermore, since the first antibacterial / antifungal / highly hydrophilic paint contains a hydrophilic resin such as a water-soluble resin and a water-dispersible resin, high hydrophilicity is exhibited.

The second antibacterial and antifungal agent comprises insoluble silica,
Deposited around the reaction product of the antibacterial metal component and the antifungal organic compound, the reaction product of the antibacterial metal component and the antifungal organic compound is encapsulated in a capsule having a large number of fine pores made of silica. Take a wrapped form.

The particle size of the second antibacterial and antifungal agent is 0.0
It is preferably from 1 to 1 μm. Particle size 0.01 μm
If it is smaller than this, remarkable secondary agglomeration may occur and dispersion may be difficult. On the other hand, if it is larger than 1 μm, a mold, a processing tool, etc. used for processing a plate material such as an aluminum plate having a dried and cured film on its surface. May be worn, and the adhesion to the coated substrate, the smoothness of the coating film, and the strength of the coating film may be impaired.

The second antibacterial and antifungal agent is disclosed in, for example,
It can be produced by the method described in JP-A-194292. In addition, antibacterial metal components, antifungal organic compounds,
The hydrophilic resin and the like may be in accordance with the first antibacterial / antifungal / highly hydrophilic paint.

[0029]

[Example 1]

"Production of the first antibacterial and antifungal agent" 2.5 g of TBZ was completely dissolved in 320 ml of methyl alcohol, and 10 ml of a 10% by weight aqueous solution of silver nitrate was added to this solution to form a reaction product of silver and TBZ (hereinafter referred to as silver). -TBZ) was obtained. The white precipitate was separated by filtration, sufficiently washed with methyl alcohol and distilled water, dried at 130 ° C., and pulverized in a mortar.

JIS No. 1 water glass was diluted with distilled water to a volume ratio of 1: 1 in 10 ml of an aqueous solution of sodium silicate, and 0.25 g of the silver-TBZ and 0.7% of carboxymethyl cellulose were added.
g, 1 to 2 drops of denatured ethyl alcohol, and the mixture was subjected to ultrasonic dispersion treatment for 5 minutes, and then completely dispersed with a magnetic stirrer. While stirring 110 ml of a separately prepared 1.5 mol / l aqueous solution of ammonium sulfate with a magnetic stirrer, the aqueous solution of sodium silicate in which the silver-TBZ was dispersed was added to the aqueous solution, and the mixture was aged while stirring at 30 ° C. for 2 hours. A precipitate product was obtained. The precipitated product was separated by filtration, sufficiently washed with distilled water, dried at 130 ° C., and crushed in a mortar to obtain a first antibacterial and antifungal agent.

The first antibacterial and fungicide was confirmed by infrared absorption spectroscopy (IR) that silver-TBZ was fixed on the surface and inside of the silica, and that the silica was porous. It was confirmed by scanning electron microscope observation that the particles were fine particles having a particle size of 0.05 to 0.4 μm. The silver-TBZ content in the first antibacterial and antifungal agent was determined by the plasma emission spectrometry (ICP method).
The amounts were calculated from the weight loss values by thermal analysis (TG method). As a result, silver was 1.5% by weight and TBZ was 5.8% by weight.

Commercially available hydrophilic paint (Nippon Paint Co., Ltd.)
1% by weight of the first antibacterial and fungicide to Surfcoat 240)
It was added and dispersed by a homogenizer to obtain an antibacterial / antifungal / highly hydrophilic paint of Example 1. Apply this antibacterial / antifungal / highly hydrophilic paint to the surface of the unplated aluminum plate using a roll coater.
By baking for 2 seconds, an antibacterial / antifungal / highly hydrophilic coating film was formed to prepare a test specimen.

An antibacterial test, an antifungal test (mold resistance) test, a coating film strength test, a discoloration resistance test, a hydrophilic test and a processing abrasion test were performed on the test specimen.
It was shown to. The various test methods are as follows.

"Antibacterial test" The test specimen (before loading)
The test piece was immersed in hot water at 60 ° C. for 10 days, and during this time, the test piece was subjected to a load of exchanging hot water at a rate of once / day (after loading). The antibacterial rate was calculated based on the antibacterial property evaluation method (film adhesion method) set by the Antibacterial Products Technology Council. The evaluation was as follows. ◎: Sterilization rate 99.9% or more ○: Sterilization rate 99 or more and less than 99.9% ×: Sterilization rate less than 99%

"Antifungal (mold resistance) test" 0.5 ml of a chalet using potato dextrose agar (PDA) as a medium.
l of the fungal spore suspension was dropped and uniformly applied. A test sample was placed at the center, and 1 ml of the fungal spore suspension was dropped uniformly on the test sample. The cells were cultured for 2 weeks in an incubator set at 27 ° C. The evaluation was as follows. 3: No hyphal growth was observed on the surface of the test body. 2: The area of the growth part of the hypha on the surface of the test specimen is 1/3
Does not exceed. 1: The area of the growing portion of the hypha on the surface of the test specimen is 1/3
Exceeds.

"Coating film strength test" The coating surface of the test piece was 5 m wide.
The cross cut (60 mm × 50 mm) was performed at m, and peeling was attempted with a cellophane tape, and the number of squares remaining without peeling out of 100 squares was measured. The evaluation was as follows. ：: Remaining state 90/100 or more ○: Remaining state 70/100 or more and less than 90/100 ×: Remaining state less than 70/100

"Discoloration resistance test" A specimen was placed in a 3% saline solution.
It was immersed for 400 hours, washed with water, and dried at 60 ° C. The color change of the color tone before and after the salt solution immersion treatment was measured with a color analyzer E (TC-1800MK II, manufactured by Tokyo Denshoku Co., Ltd.). The evaluation was as follows. Note that ΔE represents a color difference. ◎: ΔE: less than 3 ○: ΔE: 3 or more and less than 10 ×: ΔE: 10 or more

"Hydrophilicity test" A test piece was treated with tap water (flow rate per minute).
(1 liter) for 7 hours, and drying in an electric oven at 80 ° C. for 17 hours was one cycle, and the water contact angle was measured continuously up to 7 cycles. To measure the water contact angle, place the specimen horizontally, drop 5 μl of pure water on it,
It was measured by a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., CA-Z). The evaluation was as follows. ◎: less than 5 ° ○: 5 ° to less than 20 ° △: 20 ° to less than 30 ° ×: 30 ° or more

"Working Abrasion Test" After 200,000 shots were formed on a test piece, evaluation was made by the amount of wear of the pierce punch. The evaluation was as follows. ◎: Wear amount less than 0.005 mm ○: Wear amount 0.005 mm or more and less than 0.010 mm ×: Wear amount 0.010 mm or more

Example 2 "Production of a second antibacterial and antifungal agent" An aqueous solution of sodium silicate prepared by diluting JIS No. 1 water glass with distilled water to a volume ratio of 1: 1.
To 10 ml, 0.25 g of the silver-TBZ, 0.7 g of carboxymethylcellulose, and 1 to 2 drops of denatured ethyl alcohol were added, and the dispersed liquid was added to benzene to which a nonionic surfactant had been added to form an emulsion. Prepared separately
The emulsion was added to 110 ml of a 1.5 mol / l ammonium sulfate aqueous solution, and aged at 30 ° C. for 2 hours with stirring to obtain a precipitate. The precipitate is centrifuged to remove the oil phase, filtered, washed sufficiently with distilled water, dried at 130 ° C., and crushed in a mortar to obtain a second antibacterial and fungicide. Obtained.

It was confirmed by infrared absorption spectroscopy (IR) that the second antibacterial and fungicide contained silver-TBZ in silica. In addition, the particle size is 0.05 to 0.4
It was confirmed by scanning electron microscope observation that the particles were fine capsule particles having a size of μm. Further, when the content of silver-TBZ in this second antibacterial and fungicide was calculated in accordance with Example 1, the content of silver was 1.7% by weight and that of TBZ was 5.7% by weight.

Commercially available hydrophilic paint (Nippon Paint Co., Ltd.)
1% by weight of the above first antibacterial and fungicide was added to Surfcoat 240) and dispersed by a homogenizer.
An antibacterial / antifungal / highly hydrophilic paint was obtained. Apply this antibacterial, antifungal, and highly hydrophilic paint to the surface of the aluminum plate that has not been subjected to corrosion resistance using a roll coater.
By baking for 30 seconds, an antibacterial / antifungal / highly hydrophilic coating film was formed to prepare a test specimen.

An antibacterial test, an antifungal test (mold resistance) test, a coating film strength test, a discoloration resistance test, a hydrophilic test and a processing abrasion test were carried out on this specimen in accordance with Example 1. The results are shown in Table 1.

[Example 3] The hydrophilic paint (Surfcoat 240, manufactured by Nippon Paint Co., Ltd.) was changed to another hydrophilic paint (Elastro W-II, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). Specimens were prepared according to Example 1. For this specimen, an antibacterial test, an antifungal test (mold resistance), a coating film strength test, a discoloration resistance test, a hydrophilicity test, and a work abrasion test were carried out in accordance with Example 1. The results are shown in Table 1.

Example 4 The hydrophilic paint (Surfcoat 240, manufactured by Nippon Paint Co., Ltd.) was changed to another hydrophilic paint (Elastro W-II, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) Specimens were prepared according to Example 1. For this specimen, an antibacterial test, an antifungal test (mold resistance), a coating film strength test, a discoloration resistance test, a hydrophilicity test and a processing wear test were carried out in accordance with Example 2, and the results were obtained. The results are shown in Table 1.

[Comparative Example 1]
Specimens were prepared in the same manner as in Example 1, except that the silver zeolite-based antibacterial agent was changed to 2.5 μm. For this specimen, an antibacterial test, an antifungal test (mold resistance), a coating film strength test, a discoloration resistance test, a hydrophilicity test, and a work abrasion test were carried out in accordance with Example 1. The results are shown in Table 1.

Comparative Example 2 The first antibacterial and antifungal agent was 2-4-
Specimens were prepared according to Example 1 except that thiazolyl benzimidazole (TBZ) was used. For this specimen, an antibacterial test, an antifungal test (mold resistance), a coating film strength test, a discoloration resistance test, a hydrophilicity test, and a work abrasion test were carried out in accordance with Example 1. The results are shown in Table 1.

[0048]

[Table 1]

[0049]

As described above, in the antibacterial / antifungal / highly hydrophilic paint according to claim 1 of the present invention, the reaction product of the antibacterial metal component and the antifungal organic compound is a porous silica particle. By containing at least an antibacterial and fungicidal agent fixed on the surface and / or inside and a hydrophilic resin, a coating film obtained by drying and curing this paint is antibacterial even after a drying and baking process at 200 to 300 ° C.・ Maintains antifungal properties, has extremely good hydrophilicity, and has good adhesion to the substrate. For example, antibacterial, antifungal, and high hydrophilicity of heat exchangers that apply antibacterial and antifungal treatment to fins And heat resistance is improved. Further, since the antibacterial and antifungal agent contained in the paint is fine, abrasion of a mold, a processing tool, and the like used for processing a plate material on which a coating film is formed can be suppressed. Thus, this antibacterial / antifungal / highly hydrophilic coating material can provide an antibacterial / antifungal / highly hydrophilic coating film suitable for fin materials for heat exchangers and the like.

Further, in the antibacterial / antifungal / highly hydrophilic paint according to the present invention, an antibacterial / antifungal agent containing a reaction product of an antibacterial metal component and an antifungal organic compound in a porous silica. By containing at least a hydrophilic resin,
In addition to the effects possessed by the antibacterial / antifungal / highly hydrophilic paint according to claim 1, the filling of B in the coating film is excellent due to its spherical shape,
In addition, since it is included, discoloration resistance is further improved.

In the antibacterial / antifungal / highly hydrophilic paint according to claim 3, the antifungal organic compound is an imidazole compound, a thiazole compound, an N-haloalkylthio compound, a pyridine compound or an isothiazolone compound. Since it is at least one selected from the group consisting of, it is possible to improve the antibacterial and fungicidal effects and to improve safety and versatility.

In the antibacterial / antifungal / highly hydrophilic paint according to claim 4, the antibacterial / antifungal agent has a particle size of 0.01 to 1 μm.
Therefore, the dispersibility of the antibacterial and fungicide in the hydrophilic resin is improved, and the wear of a mold, a processing tool, and the like used for processing a plate material on which a coating film is formed can be suppressed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a model for fixing a reaction product of an antibacterial metal component and an antifungal organic compound to a silica network structure according to an embodiment of the present invention.

FIG. 2 is a schematic view showing a model of a reaction product of an antibacterial metal component and an antifungal organic compound adhered to a silicate having a silica structure, according to an embodiment of the present invention.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Nobu Kinoshita 585 Tomimachi, Funabashi-shi, Chiba F-term in the New Technology Research Laboratory, Sumitomo Osaka Cement Co., Ltd. 4C058 AA19 BB07 JJ03 JJ05 JJ08 4H011 AA02 AA03 BA06 BB06 BB09 BB10 BB18 BC18 BC19 DA01 DA02 DA23 DC01 DE17 DH25 4J038 BA021 CG141 DB001 DD001 DF001 DG001 DH001 EA011 HA066 HA446 JB32 JB33 JC18 KA15 MA14 PC02

Claims (4)

[Claims] An antibacterial and fungicide, wherein a reaction product of an antibacterial metal component and an antifungal organic compound contains at least an antibacterial antifungal agent fixed on the surface and / or inside of porous silica particles, and a hydrophilic resin. Features antibacterial, antifungal and highly hydrophilic paints. 2. An antibacterial agent characterized in that a reaction product of an antibacterial metal component and an antifungal organic compound contains at least an antibacterial antifungal agent encapsulated by porous silica and a hydrophilic resin. Antifungal and highly hydrophilic paint. 3. The antifungal organic compound is at least one selected from the group consisting of imidazole compounds, thiazole compounds, N-haloalkylthio compounds, pyridine compounds and isothiazolone compounds. The antibacterial / antifungal / highly hydrophilic paint according to claim 1 or 2. 4. The antibacterial and antifungal agent has a particle size of 0.01 to 1 μm.
The antibacterial / antifungal / highly hydrophilic paint according to any one of claims 1 to 3, characterized in that: