JP2000095977A - Antibacterial photocatalytic coating material and antibacterial photocatalytic member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the antibacterial properties and resistances to warm water and alkalis of an acrylic-silicon coating material by incorporating, into it, a dry photocatalyst powder. SOLUTION: 5-80 wt.% (based on the solid content of the below-described acrylic-silicon coating material) dry powder of at least one photocatalyst selected from among titanium oxide, zinc oxide, tin oxide, iron oxide, zirconium oxide, tungsten oxide, chromium oxide, molybdenum oxide, ruthenim oxide, germanium oxide, etc., is added to an acrylic-silicon coating material which consists mainly of an acrylic resin contg. alkoxysilyl groups, as crosslinking sites, in the main chain, reacts with moisture in the air in the presence of a curative to undergo hydrolysis and condensation, forming stable intermolecular silicon bonds, and is cured at 0-150 deg.C, pref. 10-80 deg.C. The dry powder of at least one photocatalyst may be carried by 1-6 wt.% at least one metal selected from among silver, copper, iron, nickel, zinc, platinum, gold, paladium, cadmium, cobalt, rhodium, and ruthenium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique relating to an antibacterial photocatalytic member.

[0002]

2. Description of the Related Art An antibacterial inorganic coating disclosed in Japanese Patent No. 2776259 is an inorganic coating composed of a silicon compound and / or colloidal silica, and an antibacterial inorganic coating containing an antibacterial agent. Has a weight average molecular weight of 900 or more in terms of polystyrene, and
The above antibacterial agent is an antibacterial agent containing a component having a photocatalytic function. An antibacterial inorganic coating characterized by a component having a photocatalytic function or a metal supported on an oxide is described.

[0003]

The antibacterial inorganic coating disclosed in Japanese Patent No. 2776259 has a disadvantage that it is inferior in warm water resistance and alkali resistance since it uses a silicon compound as a binder. An object of the present invention is to provide an antibacterial photocatalytic paint having an antibacterial effect and having excellent hot water resistance and alkali resistance. The antibacterial inorganic coating disclosed in Japanese Patent No. 2776259 requires drying at 150 ° C. for 1 hour in order to cure the coating film, and cannot be cured at room temperature at 10 ° C. to 80 ° C .; There is a drawback that cannot be applied to materials. The object of the present invention has an antibacterial effect,
Another object of the present invention is to provide an antibacterial photocatalytic paint that can be cured at room temperature.

[0004]

In order to achieve the above object, the main agent is an acrylic resin containing an alkoxysilyl group as a crosslinking component, which reacts with moisture in the air in the presence of a curing agent to form an alkoxysilyl group. Acrylic silicone paint which forms a stable siloxane bond between the molecules by hydrolysis and condensation reaction of the polymer was used. It has a siloxane bond having a high binding energy at the cross-linking point, and this greatly contributes to excellent weather resistance. Acrylic silicone paint is an inorganic base material such as concrete because it contains the same alkoxysilyl group as the silane coupling agent used for the surface treatment agent, adhesion imparting agent, etc.
Shows excellent adhesion to metal substrates such as aluminum and stainless steel. The acrylic silicone paint can be cured at room temperature at 0 ° C to 150 ° C, preferably at 10 ° C to 80 ° C. 10 ° C because the resin substrate is significantly deformed and shrunk by heating above 80 ° C
It is desirable to cure at -80 ° C at room temperature. In addition, equipment such as a heating furnace is not required for room temperature curing. Since the dry powder of the photocatalyst is directly added to the antibacterial photocatalytic paint, water is not mixed into the organic solvent-based acrylic silicone paint, and the adhesion of the photocatalyst-containing acrylic silicone paint to the substrate is improved.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventor has developed an antimicrobial photocatalytic paint containing a copper-carrying photocatalyst by mixing a copper-carrying photocatalyst powder with a room-temperature-curable acrylic silicon-based paint.
An antibacterial photocatalytic surface having good warm water resistance, alkali resistance, adhesion, and weather resistance is formed by applying it to a substrate surface such as a molded article made of FRP (glass fiber reinforced plastic) such as LingCompound.

[0006] Since the resin base material is deformed and shrunk by heating at 80 ° C or more, it is preferable that the resin base material is cured at room temperature at 10 ° C to 80 ° C.

After applying the antibacterial photocatalytic paint containing a copper-supported photocatalyst to the surface of the substrate, the coating is applied at 0 ° C. to 150 ° C., preferably 10 ° C. to 8 ° C.
It was cured at room temperature at 0 ° C.

Since the water is not mixed into the organic solvent-based acrylic silicone paint by directly adding the photocatalyst dry powder to the room temperature-curable acrylic silicone paint, the adhesion of the photocatalyst-containing acrylic silicone paint to the base material is improved. .

In the present invention, the dry powder of the photocatalyst is directly added to the room temperature-curable acrylic silicone paint and mixed uniformly.

When a curing agent is added to a copper-supported photocatalyst-containing antibacterial photocatalytic coating material, gelling of the coating material starts in about 6 hours. Therefore, the curing agent was added immediately before application to a substrate.

In order to exhibit sufficient antibacterial properties by the photocatalyst, it is necessary to add the photocatalyst in an amount of 5 wt% or more based on the solid content. 80 wt% of photocatalyst content based on solid content
With the above addition, the adhesion, warm water resistance, alkali resistance and weather resistance of the coating were reduced due to the small proportion of the acrylic silicone paint. Therefore, the amount of the photocatalyst powder to be added to the acrylic silicon paint is preferably 5 wt% to 80 wt% based on the solid content. In addition, by supporting a metal on the photocatalyst powder, charge separation is promoted, and the activity of the photocatalyst is improved, so that antibacterial properties are improved.

A substrate surface coated with an antibacterial photocatalytic paint to which an antibacterial metal such as silver, copper or zinc is added can kill bacteria adhering to the surface. A substrate surface coated with an antibacterial photocatalytic paint to which an antibacterial metal is added suppresses the growth of microorganisms such as molds, algae, and moss. The photocatalyst carrying the antibacterial metal exhibits the antibacterial properties of the antibacterial metal even in a dark place, and the photocatalyst itself exerts the antibacterial properties even in a dark place. It is expected to be. Naturally, in a place where light is applied, an organic substance decomposition action is added due to the photocatalytic activity. Therefore, regardless of the presence or absence of light, the adhesion of dirt on the member surface due to microorganisms can be more effectively suppressed. It is most effective to carry copper having antibacterial and antifungal properties. The copper-carrying photocatalyst powder is obtained by adding a copper compound such as copper sulfate, copper nitrate, cupric chloride, or copper acetate as a copper compound to the photocatalytic sol, irradiating with ultraviolet light, performing photoreduction plating, and then obtaining a dry powder by a spray dryer or other methods. be able to.

The amount of the metal carried is desirably in the range of 1 wt% to 6 wt% with respect to the photocatalyst.

[0014] It is desirable that a mixture of a metal-carrying photocatalyst and a room temperature-curable acrylic silicone paint uniformly mixed with a curing agent immediately before use.

Various coating methods such as brush coating, spraying, dipping, flow coating, and bar coating can be adopted as a method of applying the antimicrobial photocatalytic paint containing a metal-supported photocatalyst. As a diluting solvent, xylene or the like can be used as needed.

The base material to which the present invention can be applied includes a bathtub, a bathroom wall material, a bathroom floor material, a bathroom grating, a bathroom ceiling, a shower hook, a bathtub handgrip, a bathtub apron, a bathtub drain plug, and a bathroom. Windows, bathroom window frames, bathroom window floorboards, bathroom lighting fixtures, drainage plates, drainage pits, bathroom doors, bathroom door frames, bathroom window bars, bathroom door bars, scoops, mats, soap tubs, tubs, bathrooms Mirrors, bath chairs, transfer boards, water heaters, bathroom storage shelves, bathroom handrails, bath lids,
Bathroom towel racks, shower chairs, bathroom parts such as basin stands, etc., kitchen kitchen backs, kitchen flooring, sinks, kitchen counters, drain baskets, dish dryers,
Dishwashers, stoves, range hoods, ventilation fans, stove igniters, stove knobs and other kitchen components, urinals, toilet bowls, traps for toilet bowls, plumbing for toilet bowls, flooring for toilets, wall materials for toilets, for toilets Ceiling, ball tap, water stopcock, cigarette, toilet seat, elevating toilet seat, toilet door, toilet booth key, toilet towel rail, toilet lid, toilet handrail, toilet counter, flash valve, tank, toilet seat with washing function Toilet parts such as water spout nozzles, wash bowls, wash traps, washroom mirrors, washroom storage shelves, drain plugs, toothbrush stands, washbasin mirror lighting equipment, washbasin counters, water soap feeders, washbasins, mouthwashers , Hand dryers, rotating towels and other washing parts, washing tubs, washing machine lids, washing machine pans, dehydration tubs, air conditioner filters, touch panels, faucet fittings, covers for human body detection sensors, Wahosu, shower water discharge part, sealants, is any one of the joint.

[0017]

EXAMPLES Example 1 Room temperature curable acrylic silicone paint (Kanekazemulak #
3251, average molecular weight 10,000, NV 58%, medium Si content, low contamination type) 90 g (solid content 52.2 wt%) of curing agent BT120S (catalyst type: organometallic, normal drying: clear enamel, strong drying) After adding 10 g of xylene, 100 parts of xylene were added.
g. 52.2 g of a copper-supported photocatalyst dry powder was added (the copper-supported photocatalyst was equivalent to 50 wt% based on the solid content).
The copper-carrying photocatalyst paint was prepared by mixing uniformly with three rolls. Copper supported photocatalyst dry powder is photocatalyst powder (made by Ishihara Sangyo,
ST-21, TiO2 content 95 wt%, X-ray particle size 20
nm, non-surface area 50 m2 / g, photocatalytic activity 3.0 / h)
300 g of pure water was added to 100 g, and 2.85 g of anhydrous copper acetate (corresponding to 1.0 g of copper) was added and mixed while stirring with a magnetic stirrer. This was irradiated with an ultraviolet illuminance of 50 mW / cm ² to an area of 75 cm ² for 10 minutes to perform photoreduction plating (corresponding to 2250 J). This was dried at 105 ° C. and then pulverized in a mortar to prepare a copper-supported photocatalyst dry powder (1 wt% copper-supported titania). FRP molding material SMC
A floor pan sample (20 cm square) of (Sheet Molding Compound, a sheet-shaped molding material composed of unsaturated polyester resin, filler, and glass fiber) was washed with water and degreased with isopropanol. When the grid was peeled off after drying at room temperature at 10 ° C. to 80 ° C. for 1 hour, no peeling was performed at 100/100. No peeling of the coating was observed when rubbed with a dry Kimwipe. No change in appearance was observed even after 5% NaOH was dropped and left for 1 hour. Even after immersion in hot water at 80 ° C. for 31 hours, the surface under the waterline was slightly whitened, but no swelling occurred and no peeling was observed. No change in appearance was observed even when irradiation with strong ultraviolet light was performed for 100 hours with a sunshine weather meter.

Example 2 Acrylic silicone paint (ultraviolet curing agent Z750 manufactured by JSR)
1) a copper-supported photocatalyst (photocatalyst ST-K03 (solid content concentration: 10 wt%, titania / silicate ratio: 50/50) with 5 wt% copper supported (to titania)) having a copper-supported photocatalyst content of 0% based on the solid content; Add to 10%, 20%, 30%, flow coat on 5cm square ABS resin, dry at room temperature at 10 ℃ ~ 80 ℃ for 1 hour to form antibacterial photocatalytic film on ABS resin surface did. 200,000 Escherichia coli were inoculated on the sample surface added so that the content of the copper-supported photocatalyst was 0%, 10%, 20%, and 30% based on the solid content. When the number of residual bacteria was measured, the 0% control sample grew to 1.6 million, while the copper-supported photocatalyst content was 10%, 20%, and 30%.
No E. coli was detected in any of the samples. This confirmed the antibacterial performance of the copper-supported photocatalyst under dark conditions.

Example 3 Photocatalyst secondary processed product (Ishihara Sangyo photocatalyst, ST-K03,
Inorganic coating agent, solid content concentration 10% (normal dry type), titania / silicate ratio 50/50, main use: antibacterial, antifouling) 7.14 g of anhydrous copper acetate is added to 1000 g, and 50 mW while stirring with a magnetic stirrer. / Cm2
(365 nm) UV lamp (Sen Special Light Source Co., Ltd.)
For 1 hour using a UV irradiator (Culab). Room temperature curing type acrylic silicone paint (Kanekazemurak # 3251, average molecular weight 10,000, NV
90 g (solid content: 52.2)
wt%) in the curing agent BT120S (catalyst type: organometallic,
For normal drying: After adding 10 g of clear enamel (strongly dryable), 1000 g of the copper-supported photocatalyst was mixed to obtain a copper-supported photocatalyst paint. Copper-supported photocatalyst content is 33 wt% based on solid content
Is equivalent to FRP molding material SMC (Sheet molding co
The floor pan of mpound, a sheet-shaped molding material comprising an unsaturated polyester resin, a filler, and glass fiber) was washed with water, degreased with isopropanol, and then flow-coated with the copper-supported photocatalytic paint. Drying at room temperature at 10 ° C. to 80 ° C. for 1 hour followed by rubbing with a dried Kimwipe did not show any peeling of the coating. Even after immersion in hot water at 80 ° C. for 31 hours, the surface under the waterline was slightly whitened, but no swelling occurred and no peeling was observed. No change in appearance was observed even when irradiation with strong ultraviolet light was performed for 100 hours with a sunshine weather meter. The copper-supported photocatalyst coating surface had a contact angle of water of 82 degrees, however, when a large amount of water was applied, a water film was formed and showed a droplet property. If it has a dripping property, it can be easily washed with a shower even if dirt adheres, and thus it is most suitable for floor pans in bathrooms and the like.

Comparative Example Photocatalyst secondary processed product (Ishihara Sangyo Photocatalyst, ST-K03,
Inorganic coating agent, solid content concentration 10% (normal dry type), titania / silicate ratio 50/50, main use: antibacterial, antifouling) 7.14 g of anhydrous copper acetate is added to 1000 g, and 50 mW while stirring with a magnetic stirrer. / Cm ²
(365 nm) UV lamp (Sen Special Light Source Co., Ltd.)
For 1 hour using a UV irradiator (Culab). The copper-supported photocatalyst content is 50 per solid.
wt%. FRP molding material SMC (Sheet mold)
A floor pan sample (20 cm square) of an ing compound, an unsaturated polyester resin, a filler, and a sheet-like molding material composed of glass fibers) was washed with water, degreased with isopropanol, and then coated with the copper-supported photocatalytic paint. When the grid was peeled off after drying at 150 ° C. for 30 minutes, it was completely peeled off at 0/100. After leaving 1% NaOH dropwise for 1 hour, the film dissolved.
After immersion in hot water at 60 ° C. for 24 hours, the film under the waterline completely peeled off.

[0021]

The antibacterial photocatalytic paint of the present invention does not impair the original coating performance of the acrylic silicone paint by uniformly mixing the photocatalyst powder with the acrylic silicone paint. Has good adhesion. The antibacterial photocatalytic paint of the present invention is characterized in that a member having an antibacterial photocatalytic coating film having excellent alkali resistance, warm water resistance and weather resistance can be formed on a substrate surface of any material. In addition, by supporting a metal such as copper having antibacterial and antifungal properties on the photocatalyst, an antibacterial and antifungal paint having higher performance and an antibacterial photocatalytic member having a base material coated with a paint can be realized.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) A01N 59/20 A01N 59/20 Z C09D 7/12 C09D 7/12 Z 133/06 133/06 183/10 183/10

Claims (5)

[Claims] 1. An antibacterial photocatalytic paint, characterized in that the acrylic silicone paint contains a photocatalyst dry powder. 2. The photocatalyst is titanium oxide, zinc oxide, tin oxide, iron oxide, zirconium oxide, tungsten oxide, chromium oxide, molybdenum oxide, ruthenium oxide,
Germanium oxide, lead oxide, cadmium oxide, copper oxide,
The antibacterial photocatalytic paint according to claim 1, wherein the paint is at least one selected from the group consisting of vanadium oxide, niobium oxide, tantalum oxide, manganese oxide, cobalt oxide, rhodium oxide, and rhenium oxide. 3. The antibacterial photocatalytic coating according to claim 1, wherein a metal is supported on the photocatalyst. 4. The method according to claim 1, wherein the metal is at least one selected from the group consisting of silver, copper, iron, nickel, zinc, platinum, gold, palladium, cadmium, cobalt, rhodium and ruthenium. 4. The antibacterial photocatalytic paint according to 3. 5. An antibacterial photocatalytic member, which is formed by applying the antibacterial photocatalytic paint according to claim 1 to a substrate and curing the coating by heat treatment or natural drying to form a coating.