JPH02295524A - Germ-free molding - Google Patents

Abstract

PURPOSE:To suppress the propagation of microorganisms on the surface of a resin molding contg. antimicrobial powder over a long-period of time and to maintain this part in a germ-free state by polishing the surface of the molding. CONSTITUTION:The surface of the resin molding, such as polyethylene, contg. the antimicrobial powder is polished. This antimicrobial powder is produced by bringing zeolite into an aq. sol. mixture contg. antimicrobial metal ions of, for example, copper, silver, zinc, tin, etc., to substitute the above mentioned ions with the ion-exchangeable ions in the zeolite. Namely, the surface area of the resin molding is increased by the surface polishing of the molding and the antimicrobial powder eventually exists much on the surface. The propagation of the microorganisms on the surface of the molding is thus suppressed over a long period of time and the surface is maintained in the germ-free state.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to aseptic molded products, and more specifically to aseptic molded products that have improved anti-slip effect by polishing the surface of resin molded products containing anti-slip powder. This is related to molded products. [Prior art] Molded products that come into direct contact with food, such as cutting boards, lunch boxes, chopsticks, rice scoops, and tableware, contain food residue even after washing with water in homes and cafeterias, and microorganisms propagate, resulting in poor hygiene. It was difficult to maintain a cane position. Measures to improve this include ultraviolet irradiation (Utility Model Application Publication No. 171936/1988, etc.), heat treatment (Utility Model Application No. 59-139242, etc.), and the use of various disinfectants such as hypochlorite and ethyl alcohol. is disclosed. However, none of these methods required special equipment, did not have a long-lasting antibacterial effect, or was unsatisfactory. [Problem to be solved by the invention] Molded products that come into direct contact with food, such as cutting boards, cannot be completely sterilized by washing with water, and many microorganisms exist and multiply.
Therefore, if these were used again, there were problems such as food being contaminated with microorganisms and causing food poisoning. Therefore, the purpose of the present invention is to contain antibacterial powder that is highly safe for the human body in a synthetic resin, thereby suppressing the proliferation of microorganisms on the surface of the resin, and also being able to maintain this state for a long period of time. The object of the present invention is to provide a ml molded product that can be manufactured by a method substantially the same as that of conventional products.

[Means to solve problems]

The present invention has been made in view of the above-mentioned problems, and relates to a blank molded product in which the surface of a resin molded product containing antibacterial powder is polished to improve the anti-sink effect.

The present invention will be explained below. In the present invention, the antibacterial powder has the characteristic that liquid and solid antibacterial agents are held in a porous inorganic carrier so that they can be directly kneaded into the resin, and the active ingredients can be gradually released. Examples of antibacterial agents include silver, copper, zinc, mercury, lead,
Metal ions and their compounds such as soot, bismuth, cadmium or thallium, halogen compounds such as stabilized chlorine, hypochlorite, chloramine, ethylene iodide, alcohols, phenols, ethers, guanidines, thiazoles , quaternary ammonium salts, thiocarbamates, and surfactants. Preferably, silver, copper, zinc, and soot ions or their Compounds are suitable. In the present invention, the inorganic carrier supports the antibacterial agent by adsorption, binding, ion exchange, etc., and the antibacterial agent dissolves in water.
It is used for the purpose of stably exhibiting antibacterial activity without decomposition.

Examples of inorganic gases include silica gel, alumina, crystalline aluminosilicate (synthetic or natural), amorphous aluminosilicate, activated clay, sepialite, clay materials, and activated carbon, which are porous and have a large specific surface area, making them antibacterial. Aluminosilicates are preferred because they can support a large amount of sex drugs. Examples of aluminosilicate include crystalline aluminosilicate commonly called zeolite, JP-A No. 53-30500,
Examples include amorphous aluminosilicates described in JP-A-61-174111 and the like. As the "zeolite" here, both natural and synthetic zeolites can be used. Zeolite is an aluminosilicate with a three-dimensional skeleton structure in one shell, and as a monocatalytic type, XMt80・＾Igos・YSiO,・
Displayed in znto. Is M here an ion? It is a metal ion that can be exchanged. n is the valence of the (metal) ion. X1 type zeolite, Y1 type zeolite, T1 type zeolite, high silica zeolite, sodalite, mordenite, analcyme,
Examples include clinobutyrolite, chabasite, and erionite. However, it is not limited to these. Amorphous aluminosilicates can also be used in the present invention. Amorphous aluminosilicate (hereinafter referred to as AAS) generally has the composition formula xMgO-Al*oi ・ySiOz・z
It is expressed as ll■0, where M is generally an alkali metal element such as sodium or potassium. Furthermore, X, y, and z indicate the molar ratio of metal oxide, silica, and crystal water, respectively. Unlike crystalline aluminosilicate, which is called zeolite, AAS is a low-quality material that does not show a diffraction pattern even in X-ray diffraction analysis.
It is thought that the structure consists of ultra-fine zeolite crystals and a complex combination of non-quality substances such as stow, lx's, MtO, etc. attached to their surfaces. A.A.S.
is generally produced by reacting an aluminum salt solution, a silicon compound solution, and an alkali metal salt solution at a predetermined concentration at a low temperature of 60°C or less, and washing with water before crystallization proceeds. AAS produced by this method has ion exchange performance almost similar to that of zeolite. Examples of manufacturing methods include JP-A-53-30500 and JP-A-61-
There is a method described in No. 174111 and the like.

The particle size of the inorganic carrier used in the present invention is set to 50 μm or less, preferably 3 μm or less, from the viewpoint of dispersion and kneading into the structure fat. Below, as an example of the antibacterial powder used in the present invention, a method for producing antibacterial zeolite, in which silver ions and the like are bonded by ion exchange, will be explained. For example, the antibacterial zeolite used in the present invention can be prepared by contacting the zeolite with a mixed aqueous solution containing antibacterial metal ions such as silver ions, copper ions, zinc ions, tin ions, etc., prepared in advance, to obtain ion-exchangeable ions in the zeolite. and the above ion. Contacting is carried out at 10-70°C, preferably 40-60°C for 3-24°C.
time, preferably 10 to 24 hours batchwise or continuously (
For example, this can be done using the column method). It is appropriate to adjust the 9H of the above mixed aqueous solution to 3 to 10, preferably 5 to 7. This adjustment is preferable because it can prevent silver oxides and the like from being deposited on the zeolite surface or into the pores. Furthermore, each ion in the mixed aqueous solution is usually supplied as a salt. For example, silver ions include nitrate, silver sulfate, silver perchlorate, silver acetate, diamine silver nitrate, diammine silver sulfate, etc.; copper ions include nitrate (aM4<■), copper sulfate, copper perchlorate, copper acetate, etc. Potassium tetracyanocuprate, etc., zinc ions, such as zinc nitrate (■), zinc sulfate, zinc perchlorate, zinc thiocyanate, zinc acetate, etc., and tin ions, tin sulfate, tin nitrate, etc. can be used. The content of ions, etc. in the zeolite can be appropriately controlled by adjusting the concentration of each ion (salt) in the mixed solution. For example, when antibacterial zeolite contains anti-ion,
The concentration of ions in the aqueous solution is 0.002M/ff~
By setting it as 0.15M/β, it is possible to appropriately add silver ion-containing it O. It is possible to obtain 1 to 5% anti-stagnation zeolite. In addition, when the antibacterial zeolite further contains copper ions and zinc ions, the copper ion concentration in the aqueous solution is 0.1M/1 to 2.3M/n-zinc ion concentration is 0.
．． 15M/1~2.8M/1, tin ion concentration 0
．． By setting 3M/fi to 1.2M/l, the copper ion content is 0.1 to 18% and the zinc ion content is 0.
．． 1-18%, tin ion containing it O. 1-7% antibacterial zeolite can be obtained. In the present invention, in addition to the mixed aqueous solution as described above, ion exchange can also be performed by using an aqueous solution containing each ion individually and bringing each aqueous solution into contact with the zeolite sequentially. The concentration of each ion in each aqueous solution can be determined according to the concentration of each ion in the mixed aqueous solution. After ion exchange, the zeolite is thoroughly washed with water and then dried. Drying is preferably carried out at 105 to 115°C under normal pressure or 70 to 90°C under reduced pressure (1 to 30 torr). In this specification, % refers to % by weight on a dry basis at 110°C.

Among the antibacterial metals, it is appropriate to add silver in an amount of 0.1 to 50%, preferably 1 to 15%, from the viewpoint of exhibiting excellent bactericidal activity. Furthermore, it is preferable to contain 0.5 to 15% of one or more of copper, zinc, mercury, tin, lead, bismuth, cadmium, chromium, and thallium. In the present invention, although it depends on the degree of polishing, the amount of anti-slip powder added to the resin molded product is 0.
It is preferable to use 1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, from the viewpoint of anti-polishing power. As the workpiece to which the present invention can be applied, any resin that can be easily molded can be used, such as thermoplastic resin, thermosetting resin, or rubber. Among these, polypropylene, polyester, polyamide, phenol resin, melamine resin, polyterephthalate, etc., which do not melt due to the heat of abrasion generated during the polishing process, and their fiber-reinforced plastics (
FRP) and plastics filled with inorganic fine particles are preferred. The above resin may be molded by any conventionally known method such as blow molding, rolling molding, extrusion molding, or injection molding. Its shape may be the same as conventionally manufactured products. As the polishing method in the present invention, any conventional method for deburring, grinding, cutting, etc. of plastic molded products can be applied. For example, there are barrel processing methods, impeller set processing methods, dry blast processing methods, wet blast processing methods, wire brush processing methods, etc., but among these methods, wet blast processing is preferred due to ease of processing and processing accuracy. Law is preferred. In the present invention, the polishing conditions are adjusted so that the surface area is 115% or more, preferably 130% or more, compared to before processing, from the viewpoint of fully demonstrating the anti-polishing force. In the case of wet plast processing method, pressurized air pressure is 2 to 14 kg/catG,
By adjusting the nozzle flow rate to 35 to 250 m/min and the abrasive discharge rate to 800 to 3,000 cc/min, and performing an even surface treatment, a molded product with a surface area of 115% or more compared to before processing can be obtained.

As the abrasive material used in the polishing process in the present invention, any abrasive material used as an abrasive material can be used. for example,
Natural products such as silica sand, whitebait, and walnut shells, glass beads,
Titanium oxide, silicon carbide, silica, alumina, carborundum, metal sand, synthetic resins such as phenol resin, melamine resin, epoxy resin, urea resin, polyester resin, guanamine resin, water, ice, dry ice, etc. However, it remains on the workpiece after machining.
From the viewpoint of high safety for the human body, water, ice, dry ice, etc. are preferable. The particle size of the abrasive is preferably 50 to 150 mesh, preferably 60 to 80 mesh, from the viewpoint of ease of processing and less residue on the workpiece. In the present invention, it is also possible to incorporate antibacterial powder into the abrasive material used in the polishing process, and to apply a processing method in which the antibacterial agent is directly attached to the surface of the workpiece. In this case, the blending ratio of antibacterial powder is 10 to 50%, preferably 20 to 50%, based on the abrasive material.
It shall be 30%. The aseptic molded product of the present invention has excellent antibacterial activity against bacteria, fungi, etc., and can be applied to resin molded products in various fields where microbial resistance is required. For example, cutting boards, chopsticks,
It is preferable to use it for food contact equipment such as rice scoops, lunch boxes, food trays, and food containers, kitchen equipment such as trash cans, sinks, and drainage ducts, and bathroom toiletry equipment such as bathtubs, bathtubs, toilet bowls, and toilet water tanks. It is not limited to. [Effects of the Invention] As described above, since the aseptic molded product of the present invention is a resin molded product containing antibacterial powder whose surface is polished, its surface area is large and the anti-stagnation powder is contained in a large amount. It exists on the surface and has the effect of suppressing the growth of microorganisms on the surface of the molded product over a long period of time, keeping it sterile. Moreover, since the production of such aseptic molded products involves only polishing the surface of the resin molded product containing an antibacterial dressing, it can be manufactured using a method that is almost the same as the manufacturing method of conventional resin molded products. There are some effects that can be achieved. [Example] The present invention will be explained in more detail below with reference to Examples. Reference example (preparation of antibacterial powder) Aluminosilicate is commercially available type A zeolite (NazO
-^1zOs: 1.9SiOx ・XH*0: Average particle size 1.5μ1), City version Y1 type zeolite (1.I
Na20H AI! os1.4siOx ・XH*
0: Average particle size 0.7 μ! 1), Japanese Patent Publication No. 61-1741
Amorphous aluminosilicate (0.9
3NaJ H AI*Oz ' 2.55SiOz
・XHgO: Three types with average particle size of 0.9 μl were used. Eight grams of salt to provide each ion for ion exchange: No., Cu(NOs), Zn(NOx)ts
Four types of SnSO were used. Table 1 shows the type of zeolite used in preparing each sample and the type and concentration of salts contained in the mixed aqueous solution. No. l~No. Nine types of antibacterial aluminosilicate samples were obtained. For each sample, water was added to 1 kg of powder that had been heat-dried at 110°C to make a 1.31 mm slurry, which was then stirred and degassed, and an appropriate amount of 0.5N nitric acid solution and water were added to make a slurry.
H was adjusted to 5 to 7, and the entire slurry was made into a 1.81 slurry. Next, for ion exchange, a mixed aqueous solution 31 of a predetermined salt with a predetermined concentration was added to bring the total volume to 4.81, and this slurry liquid was maintained at 40 to 60°C and stirred for 10 to 48 hours to reach an equilibrium state. It was kept in the same state. After ion exchange, the aluminosilicate phase was filtered and washed with room temperature water or hot water until excess silver, copper, zinc, or tin ions were removed from the aluminosilicate phase. Next, the samples were heated and dried at 110°C to obtain nine types of samples.
The obtained No. 1=No. Data for the 9 antibacterial aluminosilicate samples are shown in Table 1. Examples (Manufacture of aseptic molded products. See Examples 1 to 11 in Table 2) Each antibacterial powder obtained in the reference example was mixed with high-density polyethylene (Mitsubishi Yucalon HD-JX22), and a cutting board (30
cs x 65cm x 12 cranes) was molded by injection molding.

Wet-type plastic processing machine L manufactured by Fuji Seiki Seisakusho
Blasting was carried out using H-5 under the following conditions. The resin compounding ratio, abrasive material, etc. are shown in Table 2. Pressurized air pressure: 5 kg/as'' Q nozzle flow rate: 60 m/min Nozzle diameter: 8 dragons Projection distance: 50 am Abrasive material discharge 1: 2000 cc/min As comparative examples, Comparative Examples 1 to 3 in Table 2 are shown. We also manufactured a cutting board that was not polished.Test example (antibacterial activity test)

Claims (1)

[Scope of Claims] 1. An aseptic molded product, characterized in that the surface of the resin molded product containing antibacterial powder is polished. 2. The aseptic molded product according to claim 1, wherein the surface of the resin molded product is polished so that the surface area is 115% or more compared to that before processing. 3. The aseptic molded product according to claim 1 or 2, wherein the surface of the resin molded product is polished with a blasting abrasive material containing antibacterial powder.