JP4514433B2 - Antibacterial inorganic oxide fine particles and method for producing the same - Google Patents

Description

  The present invention relates to an antibacterial inorganic oxide fine particle and a method for producing the same, and more specifically, it is used for imparting antibacterial properties to resins, paints, fibers and the like, has good dispersibility, and has excellent antibacterial properties with a small amount of use. The present invention relates to antibacterial inorganic oxide fine particles to be exhibited and a method for producing the same.

  Conventionally, in order to impart antibacterial properties to resins, paints, fibers, etc., methods such as kneading antibacterial inorganic oxide fine particles into resins, etc. have been carried out, improving the antibacterial properties of the resins, etc., color and transparency Various antibacterial inorganic oxide fine particles that do not affect the properties of the resin have been proposed.

  As such antibacterial inorganic oxide fine particles, for example, Patent Document 1 discloses inorganic oxide spherical particles containing inorganic oxide fine particles containing an antibacterial metal component at a high content in the surface layer portion of the spherical particles. It is disclosed.

  Patent Document 2 discloses that the surface of ceramic particles mainly composed of silica and having an average particle diameter of 0.005 to 0.2 μm is mainly composed of an antibacterial metal component and at least a part of the antibacterial metal component. Describes a metal-ceramic composite antibacterial agent characterized by retaining a metal-based antibacterial composition present in a metallic state.

  Further, Patent Document 3 corresponds to an amount of 0.1 to 60% by weight based on the weight of the ceramic particles or base metal particles on the surface of ceramic particles or base metal particles having an average particle diameter of 0.01 to 0.5 μm. A fine powdery metallic antibacterial agent formed by dispersing and adhering antibacterial metal particles having an average particle diameter of 0.0001 to 0.1 μm is described.

JP 2003-95620 A JP 2000-143421 A JP-A-8-99812

  However, the conventional antibacterial inorganic oxide fine particles contain an antibacterial metal component that is not used effectively because the antibacterial metal component is also present inside the pores of the fine particle, so the content of the antibacterial metal component is large. Otherwise, there was a problem that the desired antibacterial effect could not be obtained. In addition, in order to carry an antibacterial metal by a chemical plating method or the like, a plating apparatus is required, and there is a problem that the manufacturing cost is increased. Further, when the antibacterial metal component is silver, there is a problem that the color changes when the content of the antibacterial metal component is increased.

  The object of the present invention is to solve the above-mentioned problems and to effectively use the antibacterial metal component, so that it can be manufactured at low cost, and the desired antibacterial effect can be exhibited with a small amount of the antibacterial metal component. It is to provide fine particles. Another object is to provide antibacterial inorganic oxide fine particles which do not change color even when the antibacterial metal component is silver.

The present inventor has earnestly researched antibacterial inorganic oxide fine particles that have good dispersibility when kneaded into resins, etc., no discoloration, excellent weather resistance, and excellent antibacterial properties even in a small amount of use. The invention has been completed.
That is, the first of the present invention relates to antibacterial inorganic oxide fine particles obtained by coating the surface of inorganic oxide fine particles with an inorganic compound layer containing an antibacterial metal component.
The second aspect of the present invention relates to the antibacterial inorganic oxide fine particles according to claim 1, wherein the inorganic compound layer containing the antibacterial metal component is a silica-alumina layer.
A third aspect of the present invention relates to the antibacterial inorganic oxide fine particles according to claim 1, wherein the inorganic oxide fine particles are titanium oxide, silica or alumina.
The fourth aspect of the present invention relates to the antibacterial inorganic oxide fine particles according to claims 1 to 3, wherein the inorganic oxide fine particles are fine particles having an average particle diameter in the range of 0.01 to 10 μm.
The fifth aspect of the present invention is that the inorganic compound layer containing the antibacterial metal component is 0.1 to 100 parts by weight as an oxide with respect to 100 parts by weight of the inorganic oxide fine particles. It relates to antibacterial inorganic oxide fine particles.

In the sixth aspect of the present invention, the inorganic oxide fine particles are suspended in water, and alkali is added thereto to adjust the pH of the suspension to a range of 10 to 11, and then the aqueous solution of sodium aluminate is added to the suspension. A water glass aqueous solution is added while stirring simultaneously to deposit silica-alumina hydrate on the surface of the inorganic oxide fine particles, and after carrying out dealkalization treatment, the antibacterial metal component is supported. It relates to a method for producing antibacterial inorganic oxide fine particles according to 2-5.
A seventh aspect of the present invention is the method according to the sixth aspect, characterized in that after the antibacterial metal component is supported, it is further treated with at least one selected from water glass, silicic acid and a silane coupling agent. The method for producing antibacterial inorganic oxide fine particles according to claim 6.

  The antibacterial inorganic oxide fine particles of the present invention are characterized by low antibacterial metal component content and high antibacterial activity. Further, when the antibacterial metal component is silver, when the antibacterial inorganic oxide fine particles are kneaded into a resin and used, the antibacterial inorganic oxide fine particles have a high antibacterial activity, so that the amount used is The amount of the silver component used is small, and an excellent effect such as suppression of discoloration due to silver is obtained.

  Furthermore, the antibacterial inorganic oxide fine particles of the present invention can be discolored without any decrease in antibacterial activity by treating the surface of the fine particles with at least one selected from water glass, silicic acid or a silane coupling agent. Is suppressed.

In the present invention, various inorganic oxides can be used as the inorganic oxide fine particles. For example, TiO ₂ , ZrO ₂ , SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , Sb ₂ O ₃ , WO ₃ , CeO. ₂ or a single inorganic oxide such as SiO ₂ · Al ₂ O ₃ , SiO ₂ · TiO ₂ , SiO ₂ · ZrO ₂ , Al ₂ O ₃ · TiO ₂ , Al ₂ O ₃ · CeO ₂ , TiO ₂ · Examples thereof include composite oxides such as CeO ₂ , TiO ₂ .ZrO ₂ , SiO ₂ .TiO ₂ .ZrO ₂ , and SiO ₂ .TiO ₂ .CeO ₂ . Particularly, TiO _2, SiO _2, and Al ₂ O ₃ is preferably used.

The aforementioned inorganic oxide fine particles are preferably fine particles having an average particle diameter in the range of 0.01 to 10 μm. When the average particle size of the inorganic oxide fine particles is smaller than 0.01 μm, it may not be possible to form an inorganic oxide layer containing an antibacterial metal component coated on the surface of the inorganic oxide fine particles. When the average particle diameter is larger than 10 μm, the dispersibility may be deteriorated when the obtained antibacterial inorganic oxide fine particles are kneaded into the resin. The average particle diameter of the inorganic oxide fine particles is more preferably in the range of 0.1 to 1 μm. The average particle size of the inorganic oxide fine particles depends on the size of the fine particles. When the average particle size is 0.05 μm or less, an electron microscope method is used. When the average particle size is 0.05 μm or more, the centrifugal sedimentation method is used. Measured in

As the inorganic compound forming the inorganic compound layer containing the antibacterial metal component that covers the surface of the inorganic oxide fine particles, an inorganic compound having a negative charge is used. Examples of the inorganic compound include silica-alumina and titania-silica. Silica-alumina is particularly preferable.
More preferably, the silica-alumina has a weight ratio of SiO ₂ / Al ₂ O ₃ in the range of 1/1 to 5/1. When the SiO ₂ / Al ₂ O ₃ weight ratio is smaller than 1/1, the content of the antibacterial metal component may be reduced, and the SiO ₂ / Al ₂ O ₃ weight ratio is 5/1. Even if it is larger, the content of the fungal metal component may be reduced.

  The amount of the inorganic compound layer containing the antibacterial metal component is preferably in the range of 0.1 to 100 parts by weight as an oxide with respect to 100 parts by weight of the inorganic oxide fine particles. When the amount of the inorganic compound layer is less than 0.1 parts by weight, the amount of the antibacterial metal component in the antibacterial inorganic oxide fine particles is decreased, so that the antibacterial activity may be lowered. Even if it increases, antibacterial activity does not change, so it is not economical. The amount of the inorganic compound layer is more preferably in the range of 1 to 30 parts by weight as an oxide with respect to 100 parts by weight of the inorganic oxide fine particles.

  As the antibacterial metal component in the present invention, an antibacterial metal component usually used as an inorganic antibacterial agent can be used. Specifically, silver, copper, zinc, lead, tin, bismuth, cadmium, chromium, Examples include mercury, nickel, cobalt and the like. In particular, at least one metal component selected from silver, copper, and zinc also has anti-odor, anti-bacterial, and anti-algal properties in addition to antibacterial properties, and is preferable from the viewpoint of discoloration and safety to the human body. . The amount of the antibacterial metal component is desirably 0.001% by weight or more in terms of oxide based on the total amount of the antibacterial inorganic oxide fine particles. When the content of the metal component is less than 0.001% by weight, the antibacterial action may not be sufficiently exhibited. The amount of the metal component is preferably in the range of 0.001 to 10% by weight, particularly 0.05 to 5% by weight.

Next, a method for producing antibacterial inorganic oxide fine particles will be described.
In the method of the present invention, first, fine inorganic oxide particles such as TiO ₂ , SiO ₂ , and Al ₂ O ₃ are suspended in water. The oxide concentration of the suspension is not particularly limited, but is preferably in the range of 1 to 20% by weight. Next, an alkaline aqueous solution such as caustic soda is added to the suspension to adjust the pH of the suspension to a range of 10-11. By adjusting the pH of the suspension to be in the range of 10 to 11, a part of the surface of the inorganic oxide fine particles can be burned and easily reacted. It is preferable to heat the pH-adjusted suspension to a temperature of 60 to 98 ° C.

Next, a predetermined amount of sodium aluminate aqueous solution and a predetermined amount of water glass aqueous solution are simultaneously added to the suspension while stirring, and heated and aged at a temperature of 60 to 98 ° C. for 0.5 to 5 hours to form inorganic oxide fine particles. Silica-alumina hydrate is deposited on the surface. Thereafter, the alkali is removed by performing a dealkalization treatment using a cation exchange resin or the like.
As a method for supporting the antibacterial metal component on the fine particles obtained by depositing silica-alumina hydrate on the surface of the inorganic oxide fine particles, usual methods such as the method described in JP-A-6-80527 can be adopted. is there.

In the method of the present invention, preferably, after the above-described antibacterial metal component is supported, it is further treated with at least one selected from water glass, silicic acid or a silane coupling agent. The treatment is carried out after adding at least one selected from ammonia water and water glass, silicic acid or a silane coupling agent to the aqueous suspension of the antibacterial inorganic oxide fine particles carrying the antibacterial metal component. Heat aging at a temperature of 60 to 98 ° C. for 0.5 to 5 hours, followed by washing and concentration to obtain an aqueous suspension in which the antibacterial inorganic oxide fine particles of the present invention are suspended. If desired, the aqueous suspension can be spray-dried and fired to form a particulate material composed of the antibacterial inorganic oxide fine particles of the present invention. The addition amount of at least one selected from water glass, silicic acid or a silane coupling agent is preferably in the range of 0.001 to 5% by weight based on the antibacterial inorganic oxide fine particles. In addition, as a silane coupling agent, well-known things, such as methyltrimethoxysilane and vinyltrimethoxysilane, can be used.
The antibacterial inorganic oxide fine particles treated with the water glass, silicic acid or silane coupling agent do not suppress the antibacterial property and show a more excellent discoloration suppressing effect.

A suspension was prepared by adding 7682.4 g of water to 77.6 g of titanium oxide powder (Fuji Titanium Industry Co., Ltd .: TA300, average particle size 0.3 μm), and a 3 wt% sodium hydroxide aqueous solution was added thereto. After adjusting the pH to 10.5, the mixture was heated and aged at 95 ° C. for 30 minutes. On the other hand, 1192.5 g of water was added to 7.5 g of 24 wt% water glass to prepare a diluted water glass aqueous solution, and 119.7 g of water was added to 2.7 g of 38 wt% sodium aluminate aqueous solution to prepare a diluted sodium aluminate aqueous solution.
Next, a dilute water glass aqueous solution and a dilute sodium aluminate aqueous solution were added to the titanium oxide suspension heated to 95 ° C. at an addition rate of 6.7 g / min while maintaining the temperature at 95 ° C. After completion of the addition, the mixture was further aged at 95 ° C. for 1 hour, cooled to 50 ° C., and then the cation exchange resin was added until the pH of the suspension became 4.5, and then the cation exchange resin was separated. A dealkalized suspension was obtained.

On the other hand, 300 g of water was added to 0.18 g of silver nitrate and dissolved to prepare an aqueous silver nitrate solution. Next, after adding an aqueous silver nitrate solution to the dealkalized suspension over 1 hour, the suspension is heated to a temperature of 95 ° C. and aged for 4 hours to suspend the antibacterial inorganic oxide fine particles. A liquid (A) was obtained.
Next, the water suspension (A) is dried at 130 ° C. to remove moisture, and then fired at 500 ° C. for 2 hours to form a particulate material composed of antibacterial inorganic oxide fine particles (antibacterial agent (A)). Got. In addition, the silver content of the antibacterial agent (A) was 0.30 wt%. The composition of the antibacterial agent (A) is shown in Table 1 together with the composition of the antibacterial agent described below.

  In Example 1, the aqueous suspension (A) prepared in the same manner as in Example 1 was cooled, and then the pH of the aqueous suspension (A) was adjusted to 10.5 with a 15 wt% aqueous ammonia solution. Next, the aqueous suspension was heated to 95 ° C., and 600 g of 0.5 wt% silicic acid solution was added at a rate of 10 g / min while maintaining the pH at 10.5 with a 15 wt% aqueous ammonia solution. After the addition, an aqueous suspension (B) in which antibacterial inorganic oxide fine particles treated with silicic acid by aging at 95 ° C. for 1 hour were suspended was obtained. The water suspension (B) is dried at 130 ° C. to remove moisture, and then fired at 500 ° C. for 2 hours to obtain particulate matter (antibacterial agent (B)) composed of antibacterial inorganic oxide fine particles. It was. In addition, the silver content of the antibacterial agent (B) was 0.29 wt%.

  In Example 1, 600 g of a 0.5 wt% aqueous solution of silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403) was added at 10 g / min to the aqueous suspension (A) prepared in the same manner as in Example 1. Was added at a rate of After completion of the addition, the mixture was further aged at 95 ° C. for 1 hour to obtain an aqueous suspension (C) in which the antibacterial inorganic oxide fine particles treated with the silane coupling agent were suspended. The water suspension (C) is dried at 130 ° C. to remove moisture, and then fired at 500 ° C. for 2 hours to obtain particulate matter (antibacterial agent (C)) composed of antibacterial inorganic oxide fine particles. It was. In addition, the silver content of the antibacterial agent (C) was 0.29 wt%.

Comparative Example 1

  A suspension is prepared by adding 7682.4 g of water to 77.6 g of titanium oxide powder (manufactured by Fuji Titanium Industry Co., Ltd .: TA300, average particle size 0.3 μm), and 5 wt% nitric acid is added to the suspension. The pH of the liquid was adjusted to 5.0. On the other hand, 100 g of water was added to 0.35 g of silver nitrate and dissolved to prepare an aqueous silver nitrate solution. Next, the silver nitrate aqueous solution was added to the suspension whose pH was adjusted to 5.0, and then heated to a temperature of 95 ° C. for aging for 4 hours. Next, after drying at 130 ° C. to remove moisture, baking was performed at 500 ° C. for 2 hours to obtain an antibacterial agent (D). In addition, the silver content of the antibacterial agent (D) was 0.30 wt%.

Comparative Example 2

  A suspension was prepared by adding 7682.4 g of water to 77.6 g of titanium oxide (Fuji Titanium Industry Co., Ltd., TA300, average particle size 0.3 μm), and 5 wt% nitric acid was added thereto. The pH was adjusted to 5.0. On the other hand, 1000 g of water was added to 3.5 g of silver nitrate and dissolved to prepare an aqueous silver nitrate solution. Next, the silver nitrate aqueous solution was added to the suspension whose pH was adjusted to 5.0, and then heated to a temperature of 95 ° C. for aging for 4 hours. Subsequently, after drying at 130 degreeC and water | moisture content, it baked at 500 degreeC for 2 hours, and obtained the antibacterial agent (E). In addition, the silver content of the antibacterial agent (E) was 3.01 wt%.

[Table 1] Composition of antibacterial agent
Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2
[Antibacterial agent] ABCDE
[Particle size of TiO ₂ powder] (μm) 0.3 0.3 0.3 0.3 0.3
[Ratio of SiO ₂ -Al ₂ O ₃ ] (* 1) 5 5 5 None None
[SiO ₂ / Al ₂ O ₃ ] (weight ratio) 75/25 75/25 75/25 − −
[Amount of silver supported] (wt%) 0.30 0.29 0.29 0.30 3.01
[Type of surface treatment agent] None Silicic acid SC (* 2) None None
[Amount used] (wt%) − 1.0 1.0 − −
(* 1) Ratio: SiO ₂ -Al ₂ O ₃ parts by weight / TiO ₂ 100 parts by weight
(* 2) SC: Silane coupling agent

Antibacterial evaluation test 1

The antibacterial evaluation test 1 was performed on the antibacterial agents (A) to (E) obtained in Examples 1, 2, and 3 and Comparative Examples 1 and 2.
As test bacteria, Escherichia coli IFO 3972 and Staphylococcus aureuse IFO 12732 were used, and the test bacteria were suspended in 50 mL of phosphate buffer and obtained in Examples and Comparative Examples. After adding 0.1 g of an antibacterial agent and stirring at 330 rpm for 1 hour at room temperature, the viable cell count was measured. The number of viable bacteria (A) after 1 hour of the blank test and the number of viable bacteria (B) after 1 hour of the antibacterial agent addition test are measured, and the evaluation is made by the difference in increase / decrease value (Log.A-Log.B). went. The evaluation results are shown in Table 2. The phosphate buffer solution is obtained by dissolving 34 g of potassium dihydrogen phosphate in 1000 mL of purified water, adjusting the pH to 7.2 with sodium hydroxide, and then adding 800 times with 0.85% sodium chloride solution. Diluted.

[Table 2] Antibacterial evaluation test 1
Increase / Decrease Value Difference
E. coli Staphylococcus aureus Example 1 (antibacterial agent A)>5.0> 5.0
Example 2 (antibacterial agent B)>5.0> 5.0
Example 3 (antibacterial agent C)>5.0> 5.0
Comparative Example 1 (antibacterial agent D) 0.1 0.5
Comparative Example 2 (antibacterial agent E) 3.0 3.5

Antibacterial evaluation test 2

Further, each antibacterial agent (A) to (E) is contained in PE resin in an amount of 1% by weight and molded with an injection molding machine to prepare a resin test piece. Went.
That is, among the antibacterial test (film adhesion method) “antibacterial test method for resin, etc., antibacterial test method for resin added with an inorganic antibacterial agent such as silver”, the sample sample (50 × 50 mm), medium (1 / 500-fold nutrition) was prepared, and Escherichia coli IFO 3972 and Staphylococcus aureuse IFO 12732 were used as test bacteria. In the test, inoculate 0.4 mL of the bacterial suspension on the specimen sample, cover it with a coating film, cover it, leave it at 35 ± 1 ° C and relative humidity of 90% or more for 24 hours, and then count the number of viable bacteria. Was measured.
The number of viable bacteria (A) after 24 hours of the unprocessed product and the number of viable bacteria (B) after 24 hours of the processed product are measured, and evaluation is performed based on the difference between the increase and decrease values (Log.A-Log.B). It was. The evaluation results are shown in Table 3. The 1 / 500-fold nutrition means a medium containing 10 mg / L of meat extract + 20 mg / L of peptone + 10 mg / L of sodium chloride.

[Table 3] Antibacterial evaluation test 2
Increase / Decrease Value Difference
E. coli Staphylococcus aureus Example 1 (antibacterial agent A)>5.0> 5.0
Example 2 (antibacterial agent B)>5.0> 5.0
Example 3 (antibacterial agent C)>5.0> 5.0
Comparative Example 1 (antibacterial agent D) 0.0 0.3
Comparative Example 2 (antibacterial agent E) 1.5 2.0

Discoloration evaluation test

  Next, each antibacterial agent (A) to (E) was contained in PE resin in an amount of 1% by weight, molded by an injection molding machine to prepare a resin test piece, and a discoloration evaluation test was performed on each of these resin test pieces. . In the discoloration evaluation test, the degree of discoloration was visually observed on a test piece irradiated for 50 hours with a sunshine weather meter. The evaluation results are shown in Table 4.

[Table 4] Discoloration evaluation test example 1 (antibacterial agent A) No discoloration example 2 (antibacterial agent B) No discoloration example 3 (antibacterial agent C) No discoloration Comparative example 1 (antibacterial agent D) Comparative example 2 with discoloration (Antimicrobial agent E) Significant discoloration

The antibacterial inorganic oxide fine particles of the present invention can be used in fields where conventional antibacterial agents are used, and can be applied to various applications as shown below, for example.
(1) Application to fibers In addition to antibacterial properties, various fibers can be given anti-odor, fouling, and algal resistance, and natural fibers (cotton, wool, silk, hemp, pulp) ), Semi-synthetic fibers (rayon, cupra, acetate, etc.), synthetic fibers (polyester, polyurethane, polyvinyl acetal, polyamide, polyamide, polyolefin, polyvinyl chloride, polyvinylidene chloride, polyacrylonitrile, polyfluorine, etc.), or Inorganic fibers (glass, ceramics, etc.) can be mentioned. In order to impart antibacterial, deodorant, antifungal and antialgal properties to these fibers, the fibers are brought into contact with the antibacterial inorganic oxide fine particles of the present invention, then washed with water and dried, or the fibers of the present invention A known method such as a method of spraying antibacterial inorganic oxide fine particles is employed.

  As the fiber to which antibacterial, deodorant, antibacterial and algae-proofing properties are imparted, any of raw material fibers, intermediate fiber products and final fiber products is targeted. Final textile products include, for example, general clothing (blouses, skirts, shirts, trousers, dresses, sweaters, cardigans, aprons, uniforms, pants, stockings, socks, pantyhose, bras, girdles, Japanese clothing, tabi, interlining , Belt interlining, etc.), personal items (handkerchiefs, scarves, hats, gloves, watch bands, bags, handbags, shoes, footwear, shoe rugs, etc.), interior goods (curtains, blinds, carpets, mats, tablecloths, toiletries) , Car seat covers, etc.), daily miscellaneous goods (towels, towels, mops, tents, sleeping bags, stuffed animals, filters, brushes, etc.), bedding (blankets, mattresses, towels, bedding covers, futon linings, padding, etc.) ), Products used in hospitals (white robes worn by nurses, Surgery for clothing, masks, diapers, such as a diaper cover), and the like.

(2) Application to resins and rubbers The antibacterial inorganic oxide fine particles of the present invention can impart deodorant / antifungal / algaeproof properties to thermoplastic resins, thermosetting resins and rubbers in addition to antibacterial properties. it can.
Examples of the resin include phenolic resins, urea resins, melamine resins, alkyd resins, diallyl phthalate resins, epoxy resins, polyurethane resins, silicon resins, and other thermosetting resins, polyvinyl chloride. Resin, polyvinylidene chloride resin, fluorine resin, polyvinyl fluoride resin, polyvinylidene fluoride resin, polyvinyl acetate resin, polyvinyl alcohol resin, polyvinyl formal resin, saturated polyester resin, polyethylene resin, Polypropylene resin, polystyrene resin, ABS resin, acrylic resin, polyamide resin, polyacetal resin, chlorinated polyether resin, polycarbonate resin, polyarylate resin, ethyl cellulose, cellulose acetate, cellulose nitrate, etc. Raising It is. The types of rubber include natural rubber, isoprene rubber, acrylonitrile rubber, acrylic rubber, butadiene rubber, butyl rubber, styrene rubber, chloroprene rubber, chlorohydrin rubber, polyolefin rubber, urethane rubber, Examples include elastomers and rubbers such as polysulfide rubber, silicone rubber, fluorine rubber, and fluorosilicone rubber.

  In order to impart antibacterial / deodorant / antifungal / antialgal properties to these resins or rubbers, the antibacterial / antifungal / antialgal resin or antibacterial resin is added by adding the antibacterial inorganic oxide fine particles of the present invention to these raw materials.・ Method of obtaining antifungal / algae-proof rubber, method of adding antibacterial inorganic oxide fine particles to resin for masterbatch, method of bringing antibacterial inorganic oxide fine particles into contact with resin molded product under heating, or resin It can be performed by a known method such as a method of applying antibacterial inorganic oxide fine particles to a molded product.

  Examples of the resin molded product include plates, rods, pipes, tubes, films, sheets, containers, foams, and other various molded products or composite molded products. Specific examples of resin molded products include indoor equipment (floor materials, wall materials, toilet seats, bathtubs, washstands, sinks, tables, etc.), protective cases for artworks, kitchenware (tea bowls, lunch boxes, trays, water bottles, etc.) Plastic tableware, cutting boards, beverage containers, refrigerator containers, etc.), personal items (combs, shaving tools, brushes, earphones, glasses frames, etc.), childcare items (toys, etc.), daily goods (trash cans) , Dust collectors, general containers, etc.), packaging materials (garbage bags, packaging films, etc.), automobile interior parts (handles, seats, etc.), items that can be touched by an unspecified number of people (vehicle suspension leather and its grips) , Waiting room chairs and benches, handrails, various push buttons, telephone handsets, pachinko machines, etc., medical supplies (hospital dishes, syringes, stethoscopes, surgical gloves, infusion bottles, catheters, medical equipment resin parts, etc. ), Stationery instruments (ballpoint pens, pencils, etc.) Electrical and electrical appliances (refrigerator, dish washer, washing machine, vacuum cleaner, fan, air conditioning, TV, computer, personal computer or the like), and the like.

(3) Application to other fields The antibacterial inorganic oxide fine particles of the present invention include water purifiers, water treatment agents such as pool water, fishing nets, semant structures such as bridges, steel building materials, building materials for buildings, and joinery. Materials (wallpaper, bags, shoji, tatami, etc.), ceramics (tiles, pottery, porcelain, etc.), leather products (bags, shoes, fur, wallets, regular holders, etc.), wooden products (desks, cupboards, chests, floor boards, Ceiling boards, interior materials, etc.), paper products (tissue paper, cardboard paper, paper cups, paper plates, etc.), glass products (vases, water tanks, etc.), metal products (sashes, kettles, car air conditioners, etc.), cosmetic materials, cats Antibacterial, deodorant, antifungal and antialgal properties can be imparted to sand and the like.

Claims (7)

Antibacterial inorganic oxide fine particles comprising inorganic oxide fine particles and a coating layer covering the surface thereof, the coating layer containing an antibacterial metal component in silica-alumina composite oxide . The silica - alumina composite oxide in a weight ratio _{(SiO 2 / Al 2 O 3} ) antibacterial inorganic oxide fine particles of claim 1, wherein in the range of 1 / 1-5 / 1.   The antibacterial inorganic oxide fine particles according to claim 1 or 2, wherein the inorganic oxide fine particles are titanium oxide, silica or alumina.   The antibacterial inorganic oxide fine particles according to claim 1, 2 or 3, wherein the inorganic oxide fine particles are fine particles having an average particle diameter in the range of 0.01 to 10 µm. The antibacterial inorganic oxidation according to claim 1, 2, 3 or 4, wherein the coating layer containing the antibacterial metal component is 0.1 to 100 parts by weight as an oxide with respect to 100 parts by weight of the inorganic oxide fine particles. Fine particles. The inorganic oxide fine particles are suspended in water, and alkali is added thereto to adjust the pH of the suspension to the range of 10 to 11. Then, the aqueous solution of sodium aluminate and the aqueous glass solution are simultaneously stirred in the suspension. silica added to the surface of the inorganic oxide fine particles with - deposited hydrated alumina, was then de-alkali treatment, to any one of claims 1 to 5, characterized in that to carry an antibacterial metal component A method for producing the antibacterial inorganic oxide fine particles as described.   7. The antibacterial property according to claim 6, wherein after the antibacterial metal component is supported, it is further treated with at least one selected from water glass, silicic acid, and a silane coupling agent. A method for producing inorganic oxide fine particles.