JP2000301623A - Antibacterial resin molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin molded product in which an adding amount of an antibacterial agent is reduced and the degree of coloring with the agent is decreased by cleaning a surface of the molding containing an antibacterial powder with a detergent containing a surfactant. SOLUTION: A surface of the resin molded product containing an antibacterial powder obtained by absorbing a water soluble metal salt selected from silver, copper and zinc to an inorganic carrier such as silica gel, alumina, crystalline alumina silicate, amorphous alumina-silicate, activated clay, sepiolite or the like is cleaned with a detergent containing a surfactant such as fatty acid salt, alkylsulfate, alkylbenzenesulfonate, alkylnaphthalenesulfonate, alkylsulfosuccinate, alkyldiphenylether disulfonate, alkylphosphate or the like. Thus, even when an adding amount of the agent is small, stable antibacterial performance can be demonstrated.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antibacterial resin molded product, and more particularly to an antibacterial resin molded product obtained by cleaning the surface of a resin molded product containing an antibacterial powder and improving its antibacterial effect.

2. Description of the Related Art Acrylic artificial marble products in which an inorganic resin is filled into an acrylic resin have excellent heat resistance, water resistance, etc. and a beautiful appearance. Top plate and various counter tops, as well as vanities, shower toilets, waterproof pans, flooring,
Used for wall materials, partitions, etc. In recent years, with increasing interest in hygiene in the living environment, anti-bacterial properties are particularly required for plumbing products such as vanities and shower toilets. In order to meet this demand, inorganic antibacterial agents have been kneaded with resin in advance, or antibacterial agents have been applied to the surface of molded products. In order to express sufficient antibacterial performance, it is necessary for the antibacterial agent to be contained in a high concentration in the resin molded product, and therefore, depending on the type of antibacterial agent used, Has the problem that the resin molded product is colored and the antibacterial action is impaired.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an antibacterial resin molded product which exhibits excellent antibacterial performance even when the amount of the antibacterial agent is small.

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the surface of a resin molded product containing an antibacterial powder is washed with a detergent containing a surfactant so that the antibacterial agent is removed. The present inventors have found that a resin molded product in which the amount of addition can be reduced and the degree of coloring by an antibacterial agent is reduced can be obtained, and the present invention has been completed. That is, the present invention
An antibacterial resin molded product obtained by washing the surface of a resin molded product containing an antibacterial powder.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The antibacterial powder used in the present invention can be obtained by adsorbing and holding a water-soluble metal salt selected from silver, copper and zinc on an inorganic carrier. Examples of the inorganic carrier include silica gel, alumina, crystalline aluminosilicate, amorphous aluminosilicate, activated clay, sepiolite, clay substance, activated carbon, phosphate, carbonate, silicate and the like. The antibacterial powder is usually composed of fine particles having an average particle diameter of about 0.1 to 3 μm. When an antibacterial powder is to be mixed into a resin molded product, the fine particles of the powder are hardly exposed on the surface and are covered with a resin skin layer. In order for the antibacterial powder to be present near the surface of the resin molded product, the smaller the particle size, the better the average particle size of the antibacterial powder in that sense is preferably 0.1 to 0.5 μm.
m. In the present invention, as a method of mixing the antibacterial powder into the resin, other than a method of directly kneading the antibacterial powder into the resin, a method of adding and mixing to the raw material monomer, and then polymerizing,
A method of adding to and mixing with the partial polymer, a method of adding to and mixing with the polymer at the end of the polymerization, and a method of adding to and mixing with the polymer pellets and molding are used. Examples of the resin that can be used in the present invention include a methacrylic resin, a styrene resin, and an unsaturated polyester resin, and a methacrylic resin is particularly preferable. To mold the above resin,
Any known method such as a mold forming method, an extrusion forming method, a blow forming method, a rolling forming method, and an injection forming method may be used. Regarding the method of manufacturing a resin molded product, taking a case of manufacturing a molded product from a methacrylic resin as an example,
Unsaturated monomers mainly composed of methyl methacrylate 20 to 8
0 to 20% by weight and 80 to 20% by weight of an inorganic powder treated with a phosphoric acid ester having a functional group chemically bonded to the monomer.
A method of blending an antibacterial inorganic powder with a slurry of the above and polymerizing and curing the powder into a predetermined shape. There is no particular limitation on the method of polymerizing and curing the slurry, for example, a method of heating in the presence of a radical polymerization initiator, a method of a so-called redox system comprising a radical polymerization initiator and an accelerator, a method of irradiating ultraviolet rays or radiation, and the like. Can be mentioned. The antibacterial resin molded product of the present invention, if necessary, for example, dyes and pigments, pattern materials, reinforcing agents, modifiers, stabilizers,
It may contain an ultraviolet absorber, a release agent, a flame retardant, a polymerization initiator, a polymerization regulator and the like. In the present invention, there is no particular limitation on the surfactant used for cleaning the surface of the resin molded product containing the antibacterial powder. Examples of surfactants include fatty acid salts, alkyl sulfate salts, alkyl benzene sulfonates, alkyl naphthalene sulfonates, alkyl sulfosuccinates, alkyl diphenyl ether disulfonates, alkyl phosphates, polyoxyethylene alkyls and alkyls. Anionic surfactants such as allyl sulfates; polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylene derivatives, oxyethylene, oxypropylene block polymers, sorbitan fatty acid esters, polyoxyethylene sorbitan esters, Polyoxyethylene sorbitol fatty acid ester,
Nonionic surfactants such as glycerin fatty acid ester, polyoxyethylene fatty acid ester, and polyoxyethylene alkylamine; cationic surfactants such as alkylamine salt, quaternary ammonium salt, alkylbetaine and amine oxide; amphoteric surfactant Agents. In the present invention, the content of the surfactant in the detergent is preferably 5% by weight or more. There is no strict upper limit for the surfactant content, but it should not exceed 40% by weight. In addition to the surfactant, the detergent may contain carbonates, silicates, phosphates, sodium sulfate, carboxymethylcellulose, and the like as auxiliaries. As a method of washing the surface of a resin molded article containing an antibacterial powder with a detergent containing a surfactant, a method of dropping, applying or spraying a detergent containing a surfactant on the surface of the resin molded article can be used. In addition, there is a method in which a sponge is impregnated with a detergent containing a surfactant and the surface of a resin molded product is rubbed. The resin molded article washed with a detergent containing a surfactant is washed with water to sufficiently wash off the detergent, and then subjected to a drying treatment.

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. Example 1 A polymerization degree of about 11 containing 2.5% by weight of methyl acrylate
After dissolving 1 kg of the methacrylic resin of Example No. 00 in 3.28 kg of methyl methacrylate and 20 g of butylene glycol dimethacrylate, aluminum hydroxide powder (“Heidilite H-310” manufactured by Showa Denko KK) was added thereto.
5.7 kg was added and stirred to obtain a slurry. After adding 10 g of a silver-based antibacterial agent having an average particle size of 0.25 μm (“Apacider AK” manufactured by Sanghi Co., Ltd.) as an antibacterial agent, an acid phosphate ester (“New Frontier S-510” manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added thereto. 3.5 g, stearic acid 5 g, 2,2 order | azobisisobutyronitrile 2
g was added and stirred to remove bubbles. The slurry thus obtained was poured into a mold assembled by sandwiching a U-shaped vinyl chloride tube between two glass plates, poured into a 60 ° C water bath for 4 hours, and then placed in a 120 ° C air bath. After holding for a time, a plate of acrylic artificial marble having a thickness of 12 mm was obtained. The release of the acrylic artificial marble flat plate from the glass plate was good, and the flat plate surface obtained had a beautiful mirror surface transferred from the glass surface. The flat plate of acrylic artificial marble thus obtained was cut into 50 mm squares to obtain test pieces. Next, sodium linear alkyl benzene sulfonate and polyoxyethylene alkyl ether were added in an amount of 20%.
The commercially available detergent (“Life Fresh” manufactured by Oriex Co., Ltd.) was lathered and impregnated in a sponge. The surface of the test piece was rubbed with the sponge, left for about 3 minutes, and then the detergent was flushed with running water. did. The evaluation of antibacterial properties was carried out by a test in accordance with the “Self-Specific Standard for Inorganic Antibacterial Agents such as Silver and the Antibacterial Testing Method Antibacterial Testing Method for Antibacterial Products 1 (1995 Version) Film Adhesion Method”. Preparation of test solution: The turbidity (0D600) of the bacteria cultured overnight at 37 ° C. in a bouillon medium was measured, and diluted with a 1/500 concentration bouillon medium so that OD600 = 0.01. did. Test operation: The test surface was wiped with gauze immersed in an 80% ethanol aqueous solution and air-dried. One sample was placed in a sterile petri dish, and 0.5 ml of the test bacterial solution was dropped. The test bacterial solution was covered with a sterile film cut into a square of 5 cm (to make the bacterial solution adhere to the entire surface of the sample), and cultured in a wet box at 30 ° C. for 24 hours. After completion of the culture, the bacterial solution was washed out with 10 ml of a phosphate buffer, and the number of viable cells was measured. As a control of the number of bacteria at the time of inoculation (0 hour) and the number of viable bacteria 24 hours later, a bacterial solution was dropped on a sterilized petri dish by the same operation. Immediately after the addition, the bacterial solution was collected and measured. ¢ Mod value = log (B / A) or log (C / A) ¢ Mod value difference = log (B / A) −log (C / A) (= log (B / C)) A: 0 Time control bacterial count B: Bacterial count after culturing for 24 hours on a sterile Petri dish C: Bacterial count after culturing for 24 hours on specimen The evaluation results are shown in Table 1. Comparative Example 1 An acrylic artificial marble plate having a thickness of 12 mm similar to that obtained in Example 1 was cut into a 50 mm square, and the antibacterial property was evaluated in the same manner as in Example 1 except that the surface was washed away with running water. Was. Table 1 shows the evaluation results. Comparative Example 2 Same as Example 1 except that the same acrylic artificial marble plate having a thickness of 12 mm as that obtained in Example 1 was cut into a 50 mm square, and gas nitrogen was blown on the surface to blow off chips and the like. Was evaluated for antibacterial properties. Table 1 shows the evaluation results. Comparative Example 3 A flat plate was obtained in the same manner as in Example 1 except that 20 g of a silver-based antibacterial agent was added to the slurry of Example 1. Table 1 shows the evaluation results of the antibacterial properties.

[Table 1]

The antibacterial resin molded product of the present invention is characterized in that the surface of the resin molded product containing the antibacterial powder is washed with a detergent containing a surfactant or the like, so that the amount of the antibacterial agent added is small. However, stable antibacterial performance can be exhibited.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 33/10 C08L 33/10 // B29K 33:04 F term (Reference) 3E067 BA02A BB14A BB22A GC05 4F073 AA09 BA18 BA19 BA23 BA52 EA01 EA11 EA77 4F201 AA21 AB01 AF09 AM10 BA07 BC12 BD01 BR38 4J002 BC021 BG051 BG061 CF211 DA016 DE146 DE187 DE216 DH046 DJ006 DJ016 DJ036 FB076 FD186

Claims (3)

[Claims] 1. An antibacterial resin molded product obtained by cleaning the surface of a resin molded product containing an antibacterial powder. 2. The antibacterial resin molded product according to claim 1, wherein the resin containing the antibacterial powder is methacrylic artificial marble. 3. The antibacterial resin molded product according to claim 1, wherein the surface of the resin molded product is washed with a detergent containing a surfactant.