JPH1081604A - Antimicrobial and antifungal powder and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce an antimicrobial and antifungal powder, having sufficient antimicrobial and antifungal activities and improved in dispersibility and discoloring properties for a coating material or a plastic, etc., by making a metallic compound having the antimicrobial and antifungal activities stick onto substrate particles according to a specific means. SOLUTION: This antimicrobial and antifungal powder is produced by depositing (B) a metallic oxide and/or a hydrous metallic oxide having no antimicrobial and antifungal activity onto (A) substrate particles and further depositing (C) a metallic compound having the antlmicrobial and antifungal activities on the metallic oxide and/or hydrous metallic oxide B. Since the metallic oxide or hydrous metallic oxide B or both stick onto the substrate particles A in the form of fine particles when depositing the metallic oxide and/or hydrous metallic oxide B thereon, many gaps can be formed among the mutual fine particles to substantially extend the surface area of the substrate particles A. Thereby, the dispersibility of the substrate particles A for a coating material or a plastic can be improved. Since the metallic compound C sticks to the gaps present in the metallic oxide and/or hydrous metallic oxide B, the discoloring properties for the coating material or the plastic, etc., can be improved and sufficient antimicrobial and antifungal effects are obtained. An oxide, etc., of titanium can be cited as the substrate particles A and a metallic oxide or hydrous metallic oxide such as Al, Si or Co can be cited as the metallic oxide or hydrous metallic oxide B. A compound, etc., of silver, copper or zinc can be cited as the metallic compound C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a powder having antibacterial and antifungal properties and a method for producing the same.

[0002]

2. Description of the Related Art Antibacterial and antifungal powders can be added to various plastics, rubbers, paints, inks, cosmetics and the like to impart antibacterial and antifungal properties. Conventional antibacterial and antifungal powders include titanium, magnesium,
There is known a composition in which a metal element having antibacterial and antifungal properties is adhered to substrate particles such as oxides of aluminum and silicon (Japanese Patent Application Laid-Open Nos. 63-88109 and 2-2).
25402).

[0003]

The above-mentioned antibacterial and antifungal powder has the following problems. Conventional antibacterial and antifungal powders have poor dispersibility in paints and plastics, and when used in paints and plastics, are used in an agglomerated state. However, a large amount of antibacterial and antifungal powder must be added to paints and plastics. In addition, when a metal having antibacterial and antifungal properties is used, paints and plastics are colored. When adding antibacterial and antifungal powder containing silver ions and silver compounds having antibacterial and antifungal properties to paints and plastics, the raw material resin reacts with silver ions and silver compounds,
Alternatively, when the obtained paint or plastic is irradiated with light, silver ions or silver compounds are reduced, and metallic silver is generated, and the paint or plastic is colored. Further, when the base particles have photoactivity, when a metal compound such as silver or copper is directly adhered to the base particles, the photoactivity increases, and when the antibacterial and antifungal powder is irradiated with light, the raw resin may be decomposed. Or discolor.

In order to improve the above-mentioned problems of dispersibility in paints and plastics and discoloration of raw resin,
An antibacterial and antifungal powder further comprising a layer of silicon, aluminum oxide or the like on a base particle to which a metal element having antibacterial and antifungal properties is adhered (US Pat.
P. No. 5, 180, 585). However,
Even if a layer of silicon, aluminum oxide, etc. is provided on a metal element having antibacterial and antifungal properties, the discoloration of the raw material resin is not sufficiently improved, and a layer of silicon, aluminum oxide, etc. However, there is a problem that the antibacterial and antifungal effects are hardly exhibited because the metal element covers the metal element having antibacterial and antifungal properties.

[0005]

The present inventors have conducted various studies to solve the above problems, and as a result, have found that metal oxides having no antibacterial and antifungal properties on the base particles (A) and / or Alternatively, when the hydrated metal oxide (B) is deposited, the metal oxide and / or the hydrated metal oxide adhere in the form of fine particles, so that many gaps are formed between the fine particles and the surface area of the base particles (A) is reduced. It can be substantially expanded to improve dispersibility in paints and plastics, and then, when the metal compound (C) having antibacterial and antifungal properties is deposited on the above (B), it is present in (B) In the gap (C)
Is attached, so that it can improve discoloration to paints and plastics, easily exhibit antibacterial and antifungal effects, and obtain sufficient antibacterial and antifungal effects. The present inventors have found that, when they have activity, the decomposition of the raw material resin due to photoactivity is suppressed, and completed the present invention.

That is, an object of the present invention is to provide an antibacterial and antifungal powder having sufficient antibacterial and antifungal properties, and further having improved dispersibility and discoloration in paints and plastics. Another object of the present invention is to provide a method for easily and efficiently producing the antibacterial and antifungal powder.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, a metal oxide having no antibacterial and antifungal properties and / or a hydrated metal oxide (B) is adhered onto substrate particles (A). And / or a metal compound (C) having antibacterial and antifungal properties attached to the hydrated metal oxide (B). The base particles (A) are support particles that support a metal compound having antibacterial and antifungal properties. As the base particles, zinc,
Metal compounds and polymer compounds such as aluminum, silicon, cobalt, zirconium, tin, cerium, titanium, iron, nickel, barium, magnesium, manganese, and phosphorus can be used. In particular, titanium oxide or hydrated oxide having excellent hiding power as a white pigment is preferable as the base particles, and titanium oxide is more preferable.
The shape of the base particles is not particularly limited, and may be spherical,
Various shapes such as a substantially spherical shape, a granular shape, a needle shape, a plate shape, and a fiber shape can be used. As the size of the base particles,
About 0.01 to 10 μm is appropriate, and 0.05 to 1 μm.
m is preferable, and the range of 0.1 to 0.5 μm is most preferable. If the size of the base particles is smaller than the above range, the surface area of the base particles is large, and the base particles are not easily aggregated and dispersed.
If the size of the base particles is larger than the above range, a large amount of antibacterial and antifungal powder is required, which is not preferable. Further, as the base particles, those having porosity or those having no porosity can be used without distinction. The specific surface area of the substrate particles is preferably about 1 to 500 m ² / g,
The range of １００100 m ² / g is more preferred. If the specific surface area of the base particles is larger than the above range, the number of surface active sites increases,
It is not preferable because the raw material resin of paints and plastics is easily discolored, and when the specific surface area of the base particles is smaller than the above range, the amount of adhesion of the metal compound having antibacterial and antifungal properties is reduced, and sufficient antibacterial and antifungal properties To obtain the property, a large amount of antibacterial and antifungal powder is required, which is not preferable.

Next, (B) is a metal oxide and / or hydrated metal oxide having no antibacterial and antifungal properties which adheres to the surface of the base particles (A). , Cobalt, zirconium, cerium, titanium, iron, nickel, barium, magnesium,
Oxides and / or hydrated oxides of metals such as manganese, phosphorus and antimony can be used, and the resulting antibacterial and antifungal powder can be further improved in dispersibility and discoloration in paints and plastics. Is preferred. In particular, oxides and / or hydrated oxides of at least one metal selected from the group consisting of aluminum, silicon, zirconium and titanium are preferred, and more preferably at least one metal selected from the group consisting of aluminum, silicon and zirconium. It is a metal hydrated oxide. More preferably aluminum,
It is a hydrated oxide of at least two metals selected from the group consisting of silicon and zirconium, and is more excellent in discoloration resistance. Here, the hydrated oxide is an oxide containing water of hydration or water of crystallization, and includes those called hydroxides and hydrated oxides. Includes those that are partially desorbed. The content of (B) is preferably in the range of 0.05 to 20% by weight, calculated as oxide, based on the antibacterial and antifungal powder,
A range of 0% by weight is more preferred. When the content of (B) is 0.
If the amount is less than 0.05% by weight, the effect of improving dispersibility in paints and plastics and the effect of suppressing discoloration are hardly recognized, and
If the amount is more than the weight percentage, the water content increases, so that it is likely to have an adverse effect when kneading into plastics.

Next, (C) is a metal compound having antibacterial and antifungal properties, for example, silver, copper, zinc,
Tin, lead, bismuth, cadmium, chromium, and mercury metal compounds can be used, and in particular, at least one metal compound selected from the group consisting of silver, copper, and zinc compounds is preferable. As the metal compound, a poorly water-soluble inorganic compound such as an oxide, a halide, a sulfate, and a phosphate, an organic metal salt and a metal ion are preferable.
The content of (C) is preferably in the range of 0.01 to 5.0% by weight, in terms of metal, based on the antibacterial and antifungal powder,
The range is more preferably from 0.1 to 2.0% by weight. If the content of (C) is less than the above range, the antibacterial and antifungal effect is difficult to be recognized, so that it is not preferable. It is not preferable in terms of cost.

[0010] The surface of the antibacterial and antifungal powder of the present invention is treated with alkanolamines such as triethanolamine and trimethylolamine, polyethylene wax, liquid paraffin, natural paraffin, microwax, synthetic paraffin and other waxes, and dimethylpolysiloxane. A silane coupling agent having an organic reactive group of a vinyl group, such as silicon such as methylhydrogenpolysiloxane and silicone resin, vinyltrichlorosilane, vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, and vinyltrimethoxysilane; a silane coupling agent having an organic reactive group of a methacryloxy group such as γ-methacryloxypropyltrimethoxysilane;
(3,4 epoxycyclohexyl) silane coupling agent having an organic reactive group of epoxy group such as ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N- β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N-phenylpropyltriethoxysilane, N-phenyl-γ-amino Silane coupling agents having an organic reactive group of an amino group such as propyltrimethoxysilane, silane coupling agents having an organic reactive group of a mercapto group such as γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane Chloropropyl group Silane coupling agent having an organic reactive group, silane coupling agent such as trimethylchlorosilane, isopropyl triisostearoyl titanate, isopropyl tris (dioxytyl pyrophosphate) titanate, isopropyl tri (N-aminoethyl-aminoethyl) titanate , Tetraoctylbis (ditridecyl) phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltrioctanoyl titanate, isopropyldimethacrylisostearoyl titanate, isopropyltridodecylbenzenesulfonyl titanate, Isopropyl isostearyl diacryl titanate, isopropyl tri (dioctylphosph Titanate-based coupling agents such as titanate, isopropyltricumylphenyl titanate, and tetraisopropylbis (dioctylphosphite) titanate;
Aluminum-based coupling agents such as acetoalkoxyaluminum diicipropylate; fatty acids such as stearic acid and lauric acid; metals such as zinc stearate, magnesium stearate, lead stearate, sodium stearate, aluminum laurate, and aluminum stearate Fatty acid salts, fatty acid amides such as stearic acid amide, palmitic acid amide, methylene bisstearamide, ethylene bisstearamide, oleic acid amide, esylamide, butyl stearate, hydrogenated castor oil, ethylene glycol monostearate, etc. Polyesters such as esters, trimethylolpropane and pentaerythritol, alcohols such as cetyl alcohol and stearyl alcohol, and chlorinated hydrocarbons such as chlorinated naphthalene Those treated with 1 species, plastics, paints, inks, dispersibility is very good for the rubber, it is possible to further increase the antibacterial and antifungal effects of the molded article, such as plastic.

The antibacterial and antifungal powder of the present invention exerts its effects on various fungi, bacteria and fungi. For example, Bacillus subtilis (Bacillus
Subtilis), Staphylococcus aur
eus (Staphylococcus aureus), Stre
Gram-positive bacteria such as Ptococcus pyogenes (Streptococcus pyogenes), Esch
erichia coli (Escherichia coli),
Salmonella typhimurium, Klebsiella
pneumoniae (Klebsiella pneumoniae), Serratia marcescens (Serratia marcescens), Proteus morga
nii (Proseus Morgani), Proteus v
ulgaris (Proteus vulgaris), Pseu
domonas aeruginosia (Pseudomonas aeruginosa), Vibrio parahaha
gram-negative bacteria such as emoryticus (Vibrio parahaemolyticus), Trichophyton
mentagraphites (trichophyton mentagrophytes), Trichophyton rub
rum (trichophyton rubrum), Candida
albicans (Candida albicans),
Penicillium chrysogenum (Penicilium chrysogenum), Penicillium
citrinum (penicillium citrinum), C
ladosporium fulvum, Aspergillus fumi
gatus (Aspergillus fumigatus), Asp
ergillus niger, Cladosporium herbarum
(Cladosporium herbalm) and the like.

Next, the present invention relates to a method for producing an antibacterial and antifungal powder, in which the base particles (A) are first suspended in water to form an aqueous suspension, and the resulting aqueous suspension is prepared. A water-soluble compound which becomes a metal oxide and / or a hydrated metal oxide (B) having no antibacterial and antifungal properties is added, and the metal oxide and / or the hydrated metal oxide (B) are added to the base particles (A). To precipitate. Examples of the method of precipitation include: (1) a method in which the water-soluble compound as the above (B) and an acid or an alkali are simultaneously added to the above water suspension to precipitate, and (2) a water soluble compound as the above (B). Is added to the aqueous suspension first, and then an acid or alkali is added to cause precipitation,
(3) A method in which an acid or an alkali is first added to the aqueous suspension, and then the water-soluble compound serving as the component (B) is added for precipitation. Examples of the water-soluble compound to be (B) include titanium chloride (TiCl ₃ , TiCl ₄ ), titanium sulfate, titanium oxysulfate, alkali metal silicate, silicon hydroxide, alkali metal aluminate, aluminum nitrate, Zirconium sulfate, zirconium oxysulfate and the like can be mentioned, and at least one of these water-soluble compounds can be mentioned.
Seeds can be used. The product thus obtained may be filtered, washed, or dried.
An appropriate drying temperature is about 80 to 200 ° C. Further, if necessary, the obtained product may be calcined. The firing temperature is preferably from 200 to 1000 ° C.
Temperatures between 0 and 600C are more preferred. The firing atmosphere is not particularly limited, such as the atmosphere, an oxidizing atmosphere, and a reducing atmosphere.

Next, a water-soluble compound which becomes a metal compound (C) having antibacterial and antifungal properties is added to the aqueous suspension of the base particles (A) on which the above (B) has been deposited, and is precipitated. To obtain the product. As a method of precipitating, a method in which the water-soluble compound serving as (C) and a precipitant are simultaneously added to the aqueous suspension to cause precipitation, and a method in which the water-soluble compound serving as (C) is first added to the aqueous suspension And then
A method in which a precipitant is added to cause precipitation, such as a method in which a precipitant is first added to the aqueous suspension, and then the water-soluble compound serving as (C) is added to cause precipitation, can be used. Examples of the water-soluble compound to be (C) include silver nitrate, silver sulfate, copper chloride, copper sulfate, zinc chloride, zinc sulfate,
Examples thereof include a silver salt of diammine, a copper complex of tetraammine, and a zinc salt of tetraammine, and at least one of these water-soluble compounds can be used. Further, the precipitant is a substance which reacts with the water-soluble compound as the above (C) to cause precipitation of the above (C), and includes acids, alkalis, halides, sulfates, phosphates and the like. And at least one of them can be used. For example, when silver nitrate or silver sulfate is used as the water-soluble compound (C), hydrochloric acid, phosphoric acid, sodium chloride,
Sodium phosphate or the like can be used. In the present invention, the use of the above method is a preferable method because the metal compound (C) having fine antibacterial and antifungal properties can be uniformly precipitated on (B). Also,
By adding a reducing agent to the aqueous suspension, the metal compound (C) having antibacterial and antifungal properties can be reduced to a metal state.

Next, the obtained product is filtered and dried. An appropriate drying temperature is about 80 to 200 ° C. Further, if necessary, the obtained product may be calcined.
The firing temperature is preferably from 200 to 1000C,
Temperatures of 300-600 ° C are more preferred. The firing atmosphere is not particularly limited, such as the atmosphere, an oxidizing atmosphere, and a reducing atmosphere. The above-mentioned baking can firmly adhere the metal compound (C) having antibacterial and antifungal properties to (B), and can further improve the discoloration resistance. is there. Thus, the antibacterial and antifungal powder of the present invention is obtained.

The antibacterial and antifungal powder of the present invention can impart antibacterial and antifungal properties to various plastics, rubbers, paints, inks, cosmetics and the like by adding them. Examples of the plastic include low-density polyethylene, high-density polyethylene, polypropylene, hard polyvinyl chloride, soft polyvinyl chloride, polystyrene, polymethacrylate, acrylonitrile butadiene styrene (ABS), polyacetal, polyamide, polycarbonate, and polybutylene terephthalate. , Polysulfone, polyvinylidene chloride, fluorine resin,
Thermoplastic resins such as polyvinyl alcohol resin, polyvinyl formal resin, saturated polyester resin, polychlorinated ether, ethyl cellulose, cellulose acetate, and cellulose nitrate; heat of polyurethane, phenol resin, urea resin, melamine resin, epoxy resin, diallyl phthalate resin, etc. Curable resins are targeted. As rubber,
For example, diene compounds such as styrene-butadiene rubber, butadiene rubber, acrylonitrile-butadiene rubber, isoprene rubber, and chloroprene rubber, and olefin compounds such as butyl rubber and ethylene-propylene-diene rubber are applicable. As the paint, for example, alkyd resin,
Paint using a condensation polymerization type binder such as acrylic resin,
Paints using addition polymerizable binders such as polyurethane resins, paints using polymerizable reactive polymer type binders such as unsaturated polyester, polyvinyl acetate, PVC / ethylene copolymers, PVC / acrylic copolymers, poly Acrylic esters, ethylene / vinyl acetate / acrylic, acrylic / styrene, polyvinyl chloride, PVC / vinylidene chloride copolymer, emulsion paints such as styrene / butadiene, and inorganic binders such as colloidal silica and organosiloxane Paints are targeted. Examples of the ink include an ink using a rosin such as an ester gum, a rosin salt, a rosin-modified alkyd resin, and a rosin-modified phenol resin; an ink using a petroleum resin such as a c-9 petroleum resin and a cyclopentadiene resin; Inks using UV-curable / EB-curable resins such as acrylates, urethane acrylates, acrylic acid-modified alkyds, acrylic acid-modified polyesters, and inks using oxidative polymerization resins such as unsaturated polyesters, drying oil alkyds, and polybutadiene resins. Be eligible.

[0016]

EXAMPLES Examples of the present invention will be shown below, but the present invention is not limited to these examples.

Example 1 Titanium oxide produced by the chlorine method (average primary particle size 0.2
μm, a specific surface area of 10 m ² / g) is added to an aqueous solution of sodium hydroxide having a pH of 11, and 0.06 wt% of sodium pyrophosphate is added to TiO _{2 in} terms of P ₂ O _5. Then, the mixture was classified to obtain a titanium oxide aqueous suspension. The obtained titanium oxide suspension was adjusted to a concentration of 300 g / l in terms of TiO ₂ , the aqueous suspension was heated to 75 ° C. with stirring, and then the Al ₂ O was added to TiO ₂ .
₃ (30 wt% in terms of Al ₂ O ₃₎ an aqueous solution of sodium aluminate corresponding to 1.5 wt% in terms of the simultaneous addition of 20 wt% sulfuric acid aqueous solution over a period of 60 minutes to pH 7.0 And then aged for 60 minutes. Then, Ti
An aqueous solution of silver nitrate (2% by weight in terms of Ag) corresponding to 0.5% by weight in terms of Ag was added to O ₂ over 20 minutes,
Next, an aqueous hydrochloric acid solution was added to adjust the pH to 1, and the pH was adjusted to 7.0 with an aqueous sodium hydroxide solution. Then, the product was filtered, washed, and dried at a temperature of 150 ° C. An antibacterial and antifungal powder (Sample A) of the present invention was obtained. Sample A has a configuration in which a hydrated oxide of aluminum is attached to titanium oxide base particles, and silver chloride is further attached to the hydrated oxide of aluminum. The content of the hydrated oxide of aluminum in Sample A was 1.5% by weight in terms of Al ₂ O ₃ , and the content of silver chloride was 0.27% by weight in terms of metallic silver. Was.

Example 2 Titanium oxide produced by the chlorine method (average primary particle size 0.2
μm, a specific surface area of 10 m ² / g) is added to an aqueous solution of sodium hydroxide having a pH of 11, and 0.06 wt% of sodium pyrophosphate is added to TiO _{2 in} terms of P ₂ O _5. Then, the mixture was classified to obtain a titanium oxide aqueous suspension. The obtained titanium oxide suspension was adjusted to a concentration of 300 g / l in terms of TiO ₂ , the aqueous suspension was heated to 75 ° C. with stirring, and then the Al ₂ O was added to TiO ₂ .
₃ (30 wt% in terms of Al ₂ O ₃₎ an aqueous solution of sodium aluminate corresponding to 1.5 wt% in terms of the simultaneous addition of 20 wt% sulfuric acid aqueous solution over a period of 60 minutes to pH 7.0 And then aged for 60 minutes. Then, Ti
After adding an aqueous solution of silver nitrate (2% by weight in terms of Ag) corresponding to 0.5% by weight in terms of Ag to O ₂ over 20 minutes, an aqueous solution of 0.1N sodium chloride was added to the amount in terms of Ag. And added 3.6 times in molar ratio as NaCl,
Then, the obtained product is filtered, washed and dried at a temperature of 150 ° C. to obtain the antibacterial and antifungal powder of the present invention (sample B).
I got Sample B has a configuration in which a hydrated oxide of aluminum adheres to the titanium oxide base particles, and silver chloride adheres to the hydrated oxide of aluminum. This sample B
The content of the aluminum hydrated oxide was 1.5% by weight in terms of Al ₂ O ₃ , and the content of silver chloride was 0.30% by weight in terms of metallic silver.

Example 3 Titanium oxide produced by the chlorine method (average primary particle size 0.2
μm, a specific surface area of 10 m ² / g) is added to an aqueous solution of sodium hydroxide having a pH of 11, and 0.06 wt% of sodium pyrophosphate is added to TiO _{2 in} terms of P ₂ O _5. Then, the mixture was classified to obtain a titanium oxide aqueous suspension. The obtained titanium oxide suspension was adjusted to a concentration of 300 g / l in terms of TiO ₂ , the aqueous suspension was heated to 75 ° C. with stirring, and then SiO ₂ was added to TiO ₂ .
An aqueous solution of sodium silicate equivalent to 0.7% by weight in conversion (15% by weight in terms of SiO ₂ ) was added over 30 minutes,
Stir for 30 minutes, and further add Al ₂ O ₃ to TiO ₂
An aqueous solution of sodium aluminate (30% by weight in terms of Al ₂ O ₃ ) corresponding to 0.8% by weight in terms of conversion was added over 20 minutes, and after stirring for 20 minutes, a 20% by weight aqueous solution of sulfuric acid having a pH of 7. 0, and then aged for 60 minutes. Next, an aqueous solution of silver nitrate (2% by weight in terms of Ag) corresponding to 0.5% by weight of Ag was added to TiO ₂ over 20 minutes, and then an aqueous solution of hydrochloric acid was added so that the pH became 1. After further adjusting the pH to 7.0 with an aqueous sodium hydroxide solution, the product was filtered, washed,
After drying at a temperature of 150 ° C., an antibacterial and antifungal powder of the present invention (sample C) was obtained. Sample C has a structure in which a hydrated oxide of silicon and a hydrated oxide of aluminum adhere to titanium oxide base particles, and silver chloride adheres to a hydrated oxide of silicon and aluminum. The content of the silicon hydrate in Sample C was 0.7% by weight in terms of SiO ₂ , and the content of the aluminum hydrate was Al
The content was 0.8% by weight in terms of ₂ O ₃ , and the content of silver chloride was 0.30% by weight in terms of metallic silver.

Comparative Example 1 A comparative sample (sample D) was obtained in the same manner as in Example 1 except that the aqueous solution of sodium aluminate was not added. Sample D has a configuration in which silver chloride is adhered to titanium oxide base particles. The silver chloride content of this sample D was 0.27% by weight in terms of metallic silver.

5 parts by weight of the sample A obtained in Example 1 and polypropylene pellets (Ube Industries, Ltd., JI115G)
94 parts by weight, 0.5 parts by weight of zinc stearate, and 0.5 parts by weight of polyethylene wax were mixed, and the mixture was mixed with a uniaxial extruder (YSK-40, manufactured by Nakatani Machine Co., Ltd.).
Molding was performed at a temperature of 0 ° C. to prepare a masterbatch containing 5% of an antibacterial agent. On the other hand, 99 parts by weight of polypropylene pellets (JI115G, manufactured by Ube Industries, Ltd.), 0.5 parts by weight of zinc stearate, and 0.5 parts by weight of polyethylene wax were mixed, and a uniaxial extruder (manufactured by Nakatani Machinery Co., Ltd., Y
SK-40) at 220 ° C. to produce polypropylene pellets for dilution. The masterbatch containing 5% of the antibacterial agent and the polypropylene pellets for dilution were mixed so that the content of sample A was 0, 1, and 2 wt%, respectively, and an injection molding machine (SAV-30A, manufactured by Yamashiro Machinery Co., Ltd.)
A plastic plate (samples O, P and Q) of 5 × 8 × 0.3 cm was prepared at a temperature of 220 ° C. Also,
Using sample B obtained in Example 2, the same treatment was performed.
Plastic plates (samples R, S and T) were made. Further, the same treatment was performed using the sample C obtained in Example 3 to produce plastic plates (samples U, V, and W). Furthermore, the same processing was performed using the sample D obtained in Comparative Example 1 to produce a plastic plate (samples X, Y and Z).

The obtained plastic plate (samples O to
The antibacterial property of Z) was evaluated by the following method. The plastic plate was cut into 5 x 5 cm, wiped dry with ethanol-soaked gauze, and sterilized by drying. This plate was inoculated with 0.5 ml of an E. coli suspension obtained by suspending 4 × 10 ⁵ cells / ml in a normal broth medium diluted with E. coli IFO3972 (1/500). After covering with lid, temperature 35 ℃,
It was stored under the condition of a relative humidity of 90% or more. Immediately after inoculation,
After storing for 24 hours, the bacteria on the plate are removed with sterile gauze for 1 hour.
The cells were collected in 0 ml of physiological saline, the number of bacteria was measured by a plate coating method (37 ° C., 24 hours) using an ordinary agar medium, and the number of bacteria was converted into the number of bacteria per plate. The number of bacteria immediately after inoculation was 2 × 10 ⁵ cells / sample for all samples. Table 1 shows the obtained results.

[0023]

[Table 1]

Next, a plastic plate (sample Q,
T, W and Z, content of antibacterial antifungal powder 2% by weight)
Was measured by the following method. Samples Q, T, W and Z were irradiated with black light (peak wavelength 365 nm, ultraviolet intensity ² mW / cm ² ) at 20 ° C. for 240 hours.
Next, using a color difference meter (X-Rite 938), the color (L ^* ₀ , a ^* ₀ ,
b ^* ₀ ) and the color (L ^* ₁ , a ^* ₁ , b ^* ₁ ) of the sample after irradiation with black light were measured, and the color difference (ΔE) was calculated from the following equation. Table 2 shows the obtained results.

[0025]

(Equation 1)

[0026]

[Table 2]

As is clear from Tables 1 and 2, the antibacterial and antifungal powder of the present invention is superior in antibacterial and antifungal properties to the comparative sample, and at the same time has improved discoloration resistance. Was. This is because the antibacterial and antifungal powder of the present invention adheres to the base particles (A) with a metal oxide having no antibacterial and antifungal properties and / or a hydrated metal oxide (B). In addition, since the metal compound (C) having antibacterial and antifungal properties is uniformly adhered in the form of fine particles, even if reduced to the metal state by light irradiation, it is difficult to color, It is presumed that the photoactivity does not increase and the plastic is hardly deteriorated.

[0028]

According to the present invention, the antibacterial property on the base particles (A)
A metal compound having no antifungal property and / or a hydrated metal oxide (B), and further having an antibacterial and antifungal property on the metal oxide and / or hydrated metal oxide (B) (C) is an antibacterial and antifungal powder characterized by being adhered thereto, and has excellent dispersibility in paints and plastics, and is comparable to a conventional antibacterial and antifungal powder even when used in a smaller amount. It is an antibacterial and antifungal powder having an antibacterial and antifungal effect and further excellent discoloration resistance.

Further, the present invention provides a method for preparing a suspension of base particles (A) in an aqueous suspension of a metal oxide having no antibacterial and antifungal properties.
Alternatively, a water-soluble compound to be a hydrated metal oxide (B) is added and precipitated, and then a water-soluble compound to be a metal compound (C) having antibacterial and antifungal properties is added to the aqueous suspension. A product is obtained by precipitating, and then the obtained product is filtered and dried.A method for producing an antibacterial and antifungal powder, comprising drying the antibacterial and antifungal powder efficiently. Obtainable.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location A01N 59/20 A01N 59/20 Z // A01N 59/06 59/06 Z (72) Inventor Nishikawa Tomoko 2-3-1 Nishi-Shibukawa, Kusatsu City, Shiga Prefecture Ishihara Sangyo Co., Ltd. Central Research Laboratory

Claims (5)

[Claims] 1. A metal oxide and / or a hydrated metal oxide having no antibacterial and antifungal properties on substrate particles (A) (B)
And a metal compound (C) having antibacterial and antifungal properties attached to the metal oxide and / or hydrated metal oxide (B). 2. The antibacterial and antifungal powder according to claim 1, wherein the base particles (A) are an oxide or a hydrated oxide of titanium. 3. A metal oxide having no antibacterial and antifungal properties and / or a hydrated metal oxide (B), comprising aluminum,
The antibacterial antifungal powder according to claim 1, wherein the powder is an oxide and / or hydrated oxide of at least one metal selected from the group consisting of silicon, titanium and zirconium. 4. The method according to claim 1, wherein the metal compound (C) having antibacterial and antifungal properties is a compound of at least one metal selected from the group consisting of silver, copper and zinc. Antibacterial and antifungal powder. 5. A water-soluble compound which becomes a metal oxide having no antibacterial and antifungal properties and / or a water-containing metal oxide (B) is added to an aqueous suspension of the base particles (A) to precipitate. ,
Next, a water-soluble compound to be a metal compound (C) having antibacterial and antifungal properties is added to the aqueous suspension, and a product is obtained by precipitation, and then the obtained product is filtered. And a method for producing an antibacterial and antifungal powder, which is dried.