JPH0372102B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention focuses on metal ions having bactericidal action, especially silver,
The present invention relates to a method for producing a sterilizing polymer molded body comprising zeolite solid particles supporting copper or zinc ions and an organic polymer. It has been known for a long time that silver ions, copper ions, zinc ions, and the like have antibacterial properties. For example, silver ions have been widely used as disinfectants and disinfectants in the form of silver nitrate solutions. However, the solution form is inconvenient in handling and has the drawback of being limited in terms of use. Therefore, if metal ions are retained in polymers, these drawbacks will be minimized and it can be expected to be used in a wide range of fields.Various methods have been proposed as methods for retaining metal ions in polymers, such as thin metal wires. Methods of adhering or adding powders to polymers, methods of incorporating metal compounds into polymers, etc. are known. However, the method of using the metal itself has the disadvantage that the specific gravity and Young's modulus of the metal are significantly higher than those of ordinary polymers, so it is poorly compatible with the polymer, and it also requires a relatively large amount, which increases the weight and The cost will be high. On the other hand, methods using metal compounds either have a large effect on the polymer and severely limit the scope of their use, or even if this is not the case, the metal ions are simply contained or attached to the polymer. Because of this, they often fall off during use, causing problems with the sustainability of the sterilizing effect. As a method with fewer such drawbacks, a method has been proposed in which a polymer contains an organic functional group having ion exchange ability or a complex forming ability, and a metal ion is bonded to the organic functional group. However, even in this method, the interaction between the organic functional group and the polymer cannot be ignored, and whether the organic functional group is introduced into the polymer chain or an organic functional group-containing compound is added to the polymer, the interaction between the organic functional group and the polymer cannot be ignored. In order to avoid drastic changes in physical properties, the type of polymer and the type and amount of organic functional groups must be within extremely narrow ranges. 20 zeolites saturated with copper, zinc, silver etc.
Marine paints containing ~30% by weight are known (French Patent No. 1061158). However, although this paint is suitable for exterminating shellfish and algae, it was found that its bactericidal properties were not satisfactory. The present inventors have completed the present invention as a result of intensive research to improve the above-mentioned drawbacks. An object of the present invention is to provide a method for producing a polymer molded article having a bactericidal effect. That is, the object of the present invention is a mixture of 0.01 to 50 parts by weight of zeolite solid particles having a specific surface area of 150 m ² /g or more and a SiO ₂ /Al ₂ O ₃ molar ratio of 14 or less and 99.99 to 50 parts by weight of an organic polymer. and after forming,
Production of a sterilizing polymer molded article, characterized in that at least a portion of the zeolite solid particles carry ions of the metal by ion exchange using a solution of water-soluble metal salts having a sterilizing effect. It is the law. In the present invention, the zeolite solid particles are particles in which natural or synthetic zeolite made of aluminosilicate supports one or more of the above metal ions through ion exchange. Various metal ions having a bactericidal effect are known, and preferred examples include silver, copper, and zinc ions. Zeolite is generally an aluminosilicate with a three-dimensionally developed skeleton structure, and is generally xM _2/o O・Al ₂ O ₃・ySiO ₂・based on Al ₂ O ₃
It is expressed as zH ₂ O. M represents an ion-exchangeable metal ion, usually a monovalent to divalent metal, and n corresponds to this valence. On the other hand, x and y represent the coefficients of metal oxide and silica, respectively, and Z represents the number of crystallized water. Many types of zeolites are known, differing in their composition ratio, pore diameter, specific surface area, etc. However, the specific surface area of the zeolite solid particles used in the present invention must be 150 m ² /g or more (based on anhydrous zeolite), and the SiO ₂ /Al ₂ O ₃ molar ratio of the zeolite components must be 14 or less, preferably 11 or less. No. The solution of water-soluble salts of metal ions having bactericidal action, especially silver, copper and zinc, used in the present invention is
Since the zeolite defined in the present invention easily exchanges ions, it is possible to make use of this phenomenon to support the above-mentioned necessary metal ions alone or in a mixture on the zeolite stationary phase. The zeolite particles supporting ions have a specific surface area of 150 m ² /g or more and a SiO ₂ /Al ₂ O ₃ molar ratio.
Two conditions must be met: 14 or less. It has been found that if this is not the case, the object of achieving effective bactericidal action cannot be obtained. This is thought to be due to the fact that the absolute amount of metal ions fixed on the zeolite is insufficient in a state where the effect can be exerted. In other words, the amount of exchange groups in zeolite,
This is thought to be due to physicochemical properties such as exchange rate and accessibility. Therefore, zeolites with a high SiO ₂ /Al ₂ O ₃ molar ratio, known as molecular sieves, are completely unsuitable for the present invention. Furthermore, in zeolite with a SiO ₂ /Al ₂ O ₃ molar ratio of 14 or less, it is possible to uniformly support metal ions that have a bactericidal effect, and for this reason, it is only by using such zeolite that a sufficient bactericidal effect can be achieved. I found out that I can get it. In addition, the acid resistance and alkali resistance of zeolite with a high silica ratio, where the SiO ₂ /Al ₂ O ₃ molar ratio of zeolite exceeds 14, is
The silica content increases as SiO ₂ increases, but its synthesis also takes a long time, and from an economic standpoint, it is not a good idea to use a zeolite with such a high silica ratio. The above-mentioned natural or synthetic zeolite with SiO ₂ /Al ₂ O ₃ ≦14 can be used satisfactorily from the viewpoint of acid resistance and alkali resistance in the fields in which the present composition is usually considered, and is also economically acceptable. It is also cheap and a good idea. From this point of view as well, the SlO ₂ /Al ₂ O ₃ molar ratio must be 14 or less. As the zeolite material having a SiO ₂ /Al ₂ O ₃ molar ratio of 14 or less used in the present invention, either natural or synthetic zeolite can be used. For example, natural zeolite is analcime (Analcime).
_SiO2 / _Al2O3 =3.6 _{~ 5.6} ), Chabazite: _SiO2 / _Al2O3 =3.2~6.0 and 6.4~
7.6), Clinoptilolite:
_SiO2 / _{Al2O3 = 8.5-10.5} ), Erionite ( _SiO2 / _{Al2O3 =} 5.8-7.4), Faujasith ( _SiO2 / _Al2O3 =4.2-4.6),
mordenite: SiO ₂ /Al ₂ O ₃ = 8.34
~10.0), Philipsite::
SiO ₂ /Al ₂ O ₃ =2.6 to 4.4), and the like. These typical natural zeolites are suitable for the present invention. On the other hand, typical synthetic zeolites include A-type zeolite (SiO ₂ /Al ₂ O ₃ = 1.4-2.4),
-type zeolite (SiO ₂ /Al ₂ O ₃ = 2-3), Y-
_Examples include type zeolite ( _SiO2 / _Al2O3 =3-6), mordenite ( _SiO2 / _Al2O3 = _9-10 ), and the like. These synthetic zeolites are suitable as the zeolite material of the present invention. Particularly preferred are
Synthetic A-type zeolite, X-type zeolite, Y
- type zeolites and synthetic or natural mordenites. The shape of the zeolite is preferably in the form of powder particles, and the particle size may be appropriately selected depending on the application. When the molded product of the present invention is a thick molded product, for example, when it is applied to various containers, pipes, granules, or thick denier fibers, the particle size is from several microns to several tens of microns.
The particle size may be microns or several hundred microns or more, but when forming into fine denier fibers or films, the smaller the particle size is, the better; for example, in the case of clothing fibers, it is preferably 5 microns or less, particularly 2 microns or less. The organic polymer used in the present invention is a synthetic or semi-synthetic organic polymer and is not particularly limited. For example, polyethylene, polypropylene, polystyrene, polyvinyl chloride,
Polyvinylidene chloride, polyamide, polyester, polyvinyl alcohol, polycarbonate,
Thermoplastic synthetic polymers such as polyacetal, ABS resin, acrylic resin, fluorine resin, polyurethane elastomer, polyester elastomer, thermosetting synthetic polymers such as phenol resin, urea resin, melamine resin, unsaturated polyester resin, epoxy resin, urethane resin, etc. Examples include recycled or semi-synthetic polymers such as polymers, rayon, cupra, acetate, and triacetate. When a high bactericidal effect is required, it is preferable to form the mixture into a molded article with a large surface area, and one possible method is to form it into a fibrous form. From this point of view, preferred organic polymers are fiber-forming polymers, such as nylon 6 and nylon.
66, synthetic polymers such as polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, polyethylene terephthalate, polybutylene terephthalate, polyacrylonitrile, polyethylene, polypropylene and their copolymers, rayon,
Recycled or semi-synthetic polymers such as cyupra, acetate, triacetate and the like may be mentioned. In the present invention, such zeolite solid particles and an organic polymer are mixed. The proportion of zeolite solid particles (based on anhydrous zeolite) is preferably 0.01 to 50% by weight based on the total amount of zeolite solid particles and organic polymer. If it is below this lower limit, the bactericidal effect is unsatisfactory. On the other hand, even if the upper limit is exceeded, the bactericidal effect remains almost unchanged, and the physical properties of the molded product change significantly, limiting its use as a polymer molded product, so the preferred content range is 40.
It is not more than 10% by weight, especially not more than 10% by weight. When the molded article of the present invention is a fiber, a preferable range is 0.05 to 10% by weight. The mixture of zeolite solid particles and organic polymer is then formed into a suitable shape, such as fibers, films, etc.
Formed into containers, pipes, and granules. The molding method itself can be performed by a known method. The molded body is then subjected to an ion exchange process. The bactericidal metal ions must be supported on the zeolite solid particles by an ion exchange reaction. Less than the ion exchange capacity of the zeolite solid particles, especially its approx.
Ion exchange should be performed with less than 90% of the amount of metal ions. If metal compounds are simply adsorbed or adhered without ion exchange, or if ions are exchanged beyond saturation, the bactericidal effect and its sustainability will be insufficient. A method for supporting metal ions will be explained by taking as an example a case where various zeolites defined in the present invention are converted to Ag-zeolite of the present invention. usually
A solution of water-soluble silver salt such as silver nitrate is used in Ag-zeolite conversion, but care must be taken not to increase the concentration thereof. For example A-type or X-type zeolite (sodium-type)
When converting Ag-zeolite into Ag-zeolite using an ion exchange reaction, if the silver ion concentration is high (e.g. when using 1-2M _AgNO3 ), the silver ions will be replaced by sodium ions in the solid phase due to ion exchange. At the same time, silver oxides are precipitated in the zeolite solid phase. This has the disadvantage that the porosity of the zeolite is reduced and the specific surface area is significantly reduced. Furthermore, even if the specific surface area does not decrease significantly, the bactericidal activity decreases due to the presence of silver oxide itself. In order to prevent such excess silver from being deposited on the zeolite phase, the concentration of the silver solution should be diluted, e.g.
It is necessary to keep it below 0.3M, AgNO ₃ . The safest concentration of AgNO ₃ is 0.1M or less.
It was found that when an AgNO ₃ solution with such a concentration was used, the specific surface area of the Ag-zeolite obtained was almost the same as that of the original zeolite, and the bactericidal effect could be exhibited under optimal conditions. Next, when the zeolite defined in the present invention is converted to Cu-zeolite, a phenomenon similar to that of the above-mentioned Ag-zeolite occurs depending on the concentration of the copper salt used for ion exchange. For example, when converting A-type or X-type zeolite (sodium-type) to Cu-zeolite by ion exchange reaction,
When using 1MCuSO ₄ , Cu ²⁺ replaces Na ⁺ in the solid phase, but at the same time Cu ₃ is added to the zeolite solid phase.
The porosity of zeolite decreases due to the precipitation of basic precipitates such as (SO ₄ )(OH ₄ ), which has the disadvantage that the specific surface area decreases significantly. In order to prevent such excessive copper from being deposited in the zeolite phase, it is preferable to maintain the concentration of the water-soluble copper solution used in a more dilute state, for example, 0.05M or less. It has been found that the specific surface area of the Cu-zeolite obtained when using a CuSO ₄ solution of such a concentration is almost the same as that of the original zeolite, which has the advantage that the bactericidal effect can be exhibited in an optimal state. It was mentioned that when converting to Ag-zeolite and Cu-zeolite, solids may precipitate on the zeolite solid phase depending on the concentration of salts used for ion exchange, but when converting to Zn-zeolite, the salts used This phenomenon is not observed when the distance is around 2 to 3M. Zn usually used in the present invention
- Zeolite can be easily obtained by using salts at concentrations near the above. The above-mentioned Ag-zeolite, Cu-zeolite and
When carrying out the ion exchange reaction for conversion to Zn-zeolite by the batch method, the molded body may be immersed in a salt solution having the above-mentioned concentration. In order to increase the metal content in the zeolite material, the number of batch treatments can be increased. On the other hand, when treating a molded body by a column method using a salt solution having the above concentration, the target metal-zeolite can be easily obtained by filling the molded body in an adsorption tower and passing the salt solution through the adsorption tower. is obtained. The method of the present invention is based on two discoveries: that zeolites entrapped within polymers still retain ion exchange capacity, and that with appropriate ion exchange treatments, zeolites can be made to retain metal ions with bactericidal properties. Based on. The proportion of the zeolite in the compact that is ion-exchanged depends on the properties of each polymer.
In the case of relatively highly hydrophilic polymers, metal ions permeate into the interior as water permeates, so that the zeolite inside the molded body is also ion-exchanged. However, it was found that even with hydrophobic polymers, zeolites near the surface undergo ion exchange at a considerable rate. It is thought that the sterilizing power of the molded body obtained by the present invention mainly depends on the metal ions near the surface of the molded body, so there is not only no problem even if only the zeolite near the surface retains sterilizing metal ions. This is an efficient method in terms of the utilization rate of bactericidal metal ions. The amount of metal in the above metal-zeolite (based on anhydrous zeolite) is 30% by weight or less for silver, and the preferred range is 0.001 to 5% by weight.
It is in. On the other hand, regarding copper and zinc, the amount of copper or zinc in the metal-zeolite (based on anhydrous zeolite) is 35% by weight or less, and the preferable range is
It lies between 0.01 and 15% by weight. It is also possible to use silver, copper and zinc ions in combination; in this case, the total amount of metal ions may be 35% by weight or less based on the metal-zeolite (based on inorganic zeolite), and the preferred range is the amount of metal ions. Although it depends on the composition ratio, it is approximately 0.001 to 15% by weight. Further, even if metal ions other than silver, copper, and zinc, such as sodium, potassium, calcium, or other metal ions, coexist, the bactericidal effect is not hindered, so the residual or coexistence of these ions is not a problem. The amount of silver, copper, and zinc relative to the metal-zeolite (A weight %) and the amount of metal-zeolite relative to the molded body (B weight %) are both related to the bactericidal effect; if A is large, B may be small. , conversely, if A is small, B needs to be large. In order to effectively exhibit the bactericidal effect, it is desirable to adjust the value of A×B to 0.01 or more in the case of silver-zeolite, and 0.1 or more in the case of copper or zinc-zeolite. The polymer molded article of the present invention may further contain other components. Examples include polymerization catalysts, stabilizers, matting agents, brighteners, organic or inorganic pigments, inorganic fillers, and various plasticizers. Furthermore, it may contain a liquid or an organic solvent. The bonding force between the zeolite defined in the present invention and silver, copper, and zinc ions is extremely large, unlike a method in which the zeolite is held by an adsorbent such as activated carbon or alumina simply by physical adsorption. Therefore, the strong bactericidal ability of polymer moldings containing such metal-zeolites;
And its long-term persistence is particularly noteworthy as a characteristic advantage of the present invention. The zeolite defined as in the present invention has the advantage of high reactivity with Ag, Cu, and Zn, which have bactericidal activity. For example, A-type zeolite, X-type zeolite, Y-type zeolite,
The ion-exchangeable metal ions (Na ⁺ ) in chabasite easily undergo ion exchange with Ag ⁺ , Cu ²⁺ or Zn ²⁺ , and the metal ions are supported in the zeolite matrix. Furthermore, the zeolite defined as in the present invention has the advantage of high selective adsorption for Ag ⁺ , Cu ²⁺ and Zn ²⁺ . This fact indicates that Ag ⁺ , Cu ²⁺ , and Zn ²⁺ remain stable in the zeolite matrix even when the sterilizing polymer molded article of the present invention is used in liquids or water containing various other metal ions for sterilizing purposes. This means that it is supported for a long period of time and does not elute, meaning that its bactericidal activity is maintained for a long period of time. In addition, the zeolite limited as in the present invention is
Ag, Cu has a large exchange capacity and has sterilizing power.
It also has the advantage of increasing the amount of Zn ions supported. In addition, depending on the purpose of use of the sterilizing polymer molded article of the present invention, it may be supported on zeolite solid particles.
It has the advantage that the amounts of Ag, Cu, and Zn ions can be easily adjusted by ion exchange. Moreover, the zeolite defined in the present invention hardly deteriorates the physical properties of the polymer, and a wide variety of polymer types can be selected. Moreover, since the sterilizing polymer molded article of the present invention also has the functions inherent to zeolite, it is possible to utilize both antibacterial properties and functions inherent to zeolite. For example, the combined effect of zeolite's original functions of moisture absorption and adsorption and antibacterial effects can be utilized. Furthermore, it is also possible to incorporate other functional substances to exhibit a combined function of the above effects and other functions. Other functional substances include activated carbon,
There are silica gels, etc. In the case of activated carbon, the deodorizing and adsorption effects are enhanced, and in the case of silica gel, the moisture absorption effect is enhanced. Furthermore, the sterilizing polymer molded article of the present invention can be mixed or used in combination with different types of molded articles. For example, in the case of fibers, by blending, interweaving, interweaving, or interweaving with fibers that do not contain bactericidal metal ions, it is possible to create antibacterial fiber structures with widely modified textures and functions. . In the present invention, the metal ions that have a bactericidal effect are dispersed and contained on the polymer surface using zeolite as a carrier, so the metal ions are widely distributed on the surface compared to a method that uses the metal itself, and the bactericidal effect is improved. It has the characteristic of being large. Moreover, as mentioned above, metal ions are stably supported on the zeolite for a long period of time, so the bactericidal effect is excellent in long-term sustainability. EXAMPLES Next, examples of the present invention will be described, but the present invention is not limited to these examples unless the gist thereof is exceeded. In the Examples, the bactericidal effect was evaluated by the following test method. Antibacterial activity tests were conducted using the disk method. That is, the sterilizing molded body was cut into disks with a diameter of 20 m/m, which were used as test disks. Bacteria to be tested include Escherichia coli and Pseudomonas.
aeruginosa and Staphylococcus aureus, and for fungi Candida albicans. Mueller Hinton medium was used for bacteria, and Sabouraud medium was used for fungi. The test bacteria were suspended at 10 ⁸ cells/ml in physiological saline and dispersed in the medium using a 0.1 ml Conlage stick. Next, the test disk was pasted onto it. When determining antibacterial activity, in the case of bacteria, the temperature is 37℃.
After culturing for 18 hours, the presence or absence of inhibition zone formation was observed.In the case of fungi, the cells were kept at 30°C for one week and the presence or absence of inhibition zones was observed after culturing. A-type zeolite (Z ₁ ) shown in Table 1, X-
Type zeolite (Z ₂ ), Y-type zeolite (Z ₃ ) or natural mordenite 1 (Z ₄ ) were dried at 200°C under reduced pressure for 7 hours. Next, this was added to and mixed with 6 nylon dry chips of ηrel2.3 to a concentration of 0.5% by weight, and then fed to one side of the composite spinning machine, and the 6 nylon dry chips to which zeolite was not added were fed to the other side. Then, both were composite-spun and drawn at a ratio of 1:1 to obtain four types of composite yarns each having a core-sheath cross-sectional shape of 100 denier/24 filaments. The zeolite-added nylon component forms the sheath, and the zeolite-free nylon component forms the core. Next, the drawn yarn was knitted into a tube, and 10 g was collected.
The sample was immersed in 100 ml of a 1/500M silver nitrate aqueous solution and kept at room temperature with stirring for 20 hours to perform ion exchange. After the treated tubular knitted fabric was sufficiently washed with water and dried, the silver content was measured and an antibacterial activity evaluation test was conducted. Second result
Shown in the table.

【table】

[Table] As is clear from Table 2, the molded article of the present invention exhibited good antibacterial properties.

Claims (1)

[Claims] 1 Specific surface area of 150 m ² /g or more and 14 or less
Zeolite solid particles with _SiO2 / _{Al2O3 molar} ratio
After mixing 0.01 to 50 parts by weight and 99.99 to 50 parts by weight of an organic polymer and shaping the mixture, at least the zeolite solid particles are ion-exchanged using a solution of water-soluble metal salts having bactericidal activity. 1
1. A method for producing a sterilizing polymer molded article, characterized in that the part supports ions of the above-mentioned metal. 2. The method according to claim 1, wherein the ion exchange is performed under conditions that cause less precipitation of metal compounds. 3 Zeolite solid particles are A-type zeolite,
3. The method according to claim 1 or 2, wherein the method is comprised of Y-type zeolite, Y-type zeolite, or mordenite. 4. The metal ion according to any one of claims 1 to 3, wherein the metal ion having a bactericidal effect is one or more metal ions selected from the group consisting of silver, copper, and zinc. Method.