JPH0768094B2 - Antibacterial and antifungal intercalation compound and method for producing the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an antibacterial and antifungal agent using an inorganic layered compound capable of imparting antibacterial and antifungal properties to paints, fibers, building materials, films and the like. And a method for producing the same.

(Background Art) It was Switzerland's Carl von N ″ ageli that discovered that certain metal salts have algicidal activity, and they have a microscopic effect (Oligodyna).
mie). After that, it is known that it has a particularly strong effect on silver ions, copper ions, and the like, and widely exhibits antibacterial and antifungal effects. With regard to the microbiocidal bactericidal mechanism, it has been confirmed that minute amounts of metal ions act on bacterial cells. It has also been confirmed that the antibacterial effect of silver ions shows a considerable effect at a concentration of 0.04 to 0.1 ppm (Kazutoyo Takeuchi, "Hygiene management of water", first edition published in 1982, Chuo Law Publishing Co., Ltd., P163- P173). As for silver, 1% silver nitrate solution has been widely used for eye drops of neonatal ophthalmitis, colloidal silver as a healing agent, silver fluoride as a fungicide, and other external sterilization and suppuration prevention. However, at present, such liquid usage is extremely limited.

There is an antibacterial agent in which silver or a silver compound is supported by using silica gel, activated carbon, zeolite or the like as a carrier. The purpose of supporting silver or a silver compound on the carrier is to maintain / average / stabilize the antibacterial effect, to simplify the handling by solidification, and to expand the application. However, the antibacterial agents based on these carriers have a drawback that the elution amount of silver ions cannot be controlled because the binding force of silver or a silver compound with the carrier cannot be changed. If the elution amount of silver ions can be freely controlled according to the usage conditions such as the life and contact time required for the application of the antibacterial agent, expensive silver and the carrier are not wasted, so such an antibacterial agent has been desired.

In addition, zeolite generally has a problem that when it is immersed in a solution having a pH of 5 or less, the crystal structure collapses and the supported silver ions, copper ions, etc. are eluted at a high concentration. Since the inorganic layered compound is chemically stable and stable to strong acids and strong alkalis, it is desirable as a carrier for silver ions. It was thought that silver ions became unstable and turned into silver hydroxide and then black silver oxide, and the amount of silver ions eluted was so large that they could not be used as antibacterial agents.

(Object of the invention) In view of such circumstances, the present invention uses a chemically stable inorganic layered compound, stably holds silver ions between the layers, and according to the use of antibacterial / antifungal, silver It is an object of the present invention to provide an antibacterial and antifungal intercalation compound that makes it possible to control the elution amount of ions and a method for producing the same.

DISCLOSURE OF THE INVENTION In order to achieve such an object, the present invention uses a silver complex salt to stably hold silver ions between layers of an inorganic layered compound, and controls the elution amount of silver ions. , An antibacterial and antifungal intercalation compound in which the type of ligand that makes a silver complex salt is changed, a metal complex salt other than silver is mixed between layers, or a metal ion other than silver itself is mixed between layers, and a method for producing the same. Use as a summary.

Hereinafter, the present invention will be described in detail with reference to schematicized drawings.

As shown in FIG. 1 schematically showing the inorganic layered compound, fine particles A of the inorganic layered compound formed by stacking many crystal layers 1 are aggregated as shown in FIG. As the inorganic layered compound, montmorillonite,
Bentonite, chlorite, beidellite, hectorite,
Examples include teniolite, vermiculite, synthetic mica and synthetic smectite. For example, in the crystal structure of montmorillonite, a tetrahedral layer of silicic acid-an octahedral layer of alumina-a tetrahedral layer of silicic acid are stacked and combined to form a single crystal layer 1. Further, aluminum, which is the central metal of the octahedron layer, is partially replaced by magnesium having a smaller positive charge, so that the crystal layer is negatively charged. As schematically shown in FIG. 3, alkali metal ions 4 (mainly Na ⁺ or Li ⁺ ) corresponding to the negative charge 3 are present in the interlayer 2 to neutralize the negative charge 3 of the crystal layer 1. There is. Therefore, montmorillonite has a large cation exchange ability. It should be noted that the polar solvent is the interlayer 2
Since it has a function of entering and expanding the interlayer 2, even a large metal complex salt can easily enter the interlayer 2. Further, teniolite is different from montmorillonite in that the central metal of the octahedral layer is magnesium instead of alumina, but it shows the same properties as montmorillonite. Other inorganic layered compounds can be used as long as they have the same properties as montmorillonite.

The antibacterial and antifungal intercalation compound of the present invention is apparently no different from the inorganic layered compound shown in FIG. 2, but the state of the intercalation layer 2 is different. That is, while a large number of alkali metal ions 4 are present in the interlayer 2 of the inorganic layered compound as shown in FIG. 3, the interlayer 2 of the antibacterial / antifungal intercalation compound of the present invention is shown as an example. Fourth
As shown in the figure, the silver complex salt 5 and the metal complex salt other than silver or / and the metal ion 6 other than silver are interposed. It does not matter that some of the alkali metal ions 4 remain. In addition,
The amount of silver ions eluted from the antibacterial and antifungal intercalation compound when only the silver complex salt 5 is supported between the layers 2 is relatively large under the condition that the ligands are the same, and the amount of the metal complex salt other than silver and / or other than silver If the metal ions 6 are mixed, the number will decrease.
Therefore, the silver ion elution amount of the antibacterial and antifungal intercalation compound can be determined by selecting a ligand and inserting only a silver complex salt between the layers or by mixing a metal complex salt other than silver and / or a metal ion 6 other than silver. It becomes possible to control. If the equivalent ratio of the silver complex salt 5 and the metal complex salt other than silver or / and the metal ion 6 other than silver is less than about 1: 1 and the amount of the silver complex salt 5 is reduced, the elution amount of silver ion becomes unstable. It can be used with care. Further, FIG. 5 shows an embodiment of the present invention in which the interlayer 2 is viewed from above. The ammine silver complex salt 8, the ammine copper complex salt 9 and the lithium ion 7 are interposed. Needless to say, it is more effective to use a complex salt containing copper ions having an antibacterial and antifungal action as in this example. It should be noted that the antibacterial and antifungal intercalation compound according to the present invention may be used by mixing a porous material such as an inorganic layered compound, zeolite, and porous glass, and it is also possible to provide a material that combines the characteristics of the porous material. Is.

Any silver complex salt may be used as long as it has a positive charge or is polarized and is inserted and held between the layers of the inorganic layered compound. As a ligand for forming a silver complex salt by coordinating with silver, triethanolamine having a side chain has a larger elution amount of silver ions than monoethanolamine, which is a linear molecule, and a linear molecule longer than diethylenetriamine The amount of elution of silver ions is larger in triethylenetetramine. Therefore,
The elution amount of silver ions can be freely selected by changing the ligand. When the silver complex salt dissolves in water in the neutral range, it immediately separates into silver ions and ligands, and is considered to exhibit an antibacterial and antifungal action.

The metal complex salt other than silver and / or the metal ion other than silver preferably contains a metal ion having a positive charge of two or more. The more the charge is, the stronger the force for pulling the upper and lower crystal layers 1 is, and the narrower the interlayer 2 is, which is advantageous when it is desired to reduce the elution amount of silver ions. Further, even in the case of forming a hydroxide having a negative charge without forming a complex salt in ammonia such as aluminum, a small amount of aluminum ions in equilibrium with the aluminum hydroxide are attracted to the crystal layer 1 between layers. In some cases, aluminum ions are newly generated because the equilibrium state is broken and ion exchange is performed through a process of attracting aluminum ions. Therefore, it does not mean that only ions having a positive charge can enter the interlayer 2. Also, in the case of an unstable metal complex salt, for the same reason, it is often supported in the interlayer 2 as a metal ion rather than as a complex salt.

In the production of this invention, first, a silver compound, a solvent, a ligand for forming a complex salt with silver, and an inorganic layered compound are mixed,
At least one selected from metal compounds other than silver and at least one selected from ligands that form a complex salt therewith may be mixed together, or selected from metal compounds other than silver that are difficult to form a complex salt. At least one selected from the above may be combined and mixed. As the solvent, at least one selected from those which cannot prevent the formation of silver complex salt is used, but when the ligand is a liquid, the solvent may not be used in some cases.
The amount of the solvent is 0.4 ml or more per 1 g of the inorganic layered compound. If it is less than this range, a uniform antibacterial and antifungal intercalation compound cannot be obtained. The addition amount of the ligand that forms a complex salt with silver is preferably a theoretical reaction amount or more with respect to the silver compound. Below this, silver ions that do not form a complex salt are generated and become unstable in the interlayer 2, which is not preferable. The order of mixing is preferably such that the silver compound is put in the solvent, the ligand is added, and then the inorganic layered compound is added, but the mixing may be performed in any order. In addition,
In the case of mixing a metal compound other than silver, it is desirable to put the metal compound in a solvent and add a ligand, and then mix it with a previously prepared silver complex salt solution and add the inorganic layered compound thereto. However, even in this case, it does not matter if they are mixed in any order.

The antibacterial evaluation test of the antibacterial intercalation compound was performed as follows.

As bacteria, Escherichia coli (strain IFO 3301) is used. Escherichia coli previously cultivated on a standard agar medium is collected with a platinum loop and uniformly dispersed in 10 ml of sterile physiological saline placed in a test tube. At this time, if the number of collection of Escherichia coli by the platinum loop is 2, the number of bacteria per 1 ml of the bacterial solution is about 10 ⁵ to 10 ⁸ and it has been confirmed by another measurement of the number of viable bacteria. Next, put 20 ml in a 90φ glass dish prepared in advance and let it solidify, then pour 1 ml of the bacterial solution prepared above into a standard agar medium with a measuring pipette and shake the dish so that the bacterial solution spreads evenly on the surface of the medium. To Then, the dish is tilted, and the excess bacterial solution collected there is sucked up with a dropper. In this way, a petri dish for antibacterial evaluation test was prepared. On the other hand, accurately weigh 0.1 g of antibacterial and antifungal intercalation compound, add 1 ml of distilled water and mix well, and use a pair of tweezers to add a 6 mmφ disc (made by Whatman in the UK) for testing the anti-substance substance. After soaking, place it on paper and drain it. The disc thus obtained is gently placed on the agar medium of the antibacterial evaluation test petri dish previously prepared,
The cells were placed in a 36 ° C incubator for 16 hours or more, and Escherichia coli was cultivated for 16 hours or more. Due to the antibacterial action of the antibacterial and antifungal intercalation compound attached to the disc, the growth of the bacteria is blocked inside the inhibition circle, and the agar layer is transparent, but the outside of the inhibition circle becomes cloudy due to the growth of the bacteria. It was evaluated that there was an antibacterial action when a blocking circle of 1 mm or more occurred from the edge of the disk, that is, when a blocking circle of 8 mmφ or more was generated (Revised 5th Edition Bacteriological Practice Recommendation) Maruzen , 1976P-377P).

In the antifungal evaluation test, Aspergillus niger (strain IFO4414) was used as the mold, the medium was potato dextrose agar, and the culture was carried out at 24 ° C. for 3 days. The test method was performed according to the above-mentioned antibacterial property evaluation test.

For the measurement of the contents of silver and metals other than silver retained in the interlayer 2 of the antibacterial / antifungal intercalation compound, the powder of the antibacterial / antifungal intercalation compound dried in a desiccator was put into a nitric acid-aluminum nitrate solution, Ion exchange was performed with aluminum ions, and silver ions and metal ions other than silver, which were sent out into the solution, were measured with an atomic absorption spectrophotometer (AA600 type manufactured by Shimadzu) and calculated. When measuring the amount of aluminum ions between layers, iron nitrate was used instead of aluminum nitrate for ion exchange.

For the measurement of the amount of ionic elution of the antibacterial / antifungal intercalation compound, the powder of the antibacterial / antifungal intercalation compound dried in a desiccator was used.
20 ml of distilled water was added to 0.1 g, the mixture was stirred with a stirrer for 1 hour, centrifuged, and the ion concentration in the supernatant was measured with an atomic absorption spectrophotometer.

Hereinafter, examples will be described in detail.

Example 1 2 g of Na-montmorillonite was added to 0.05 N aqueous solution of ammine silver complex salt 4
The mixture was gradually added to 0 ml with stirring with a stirrer and reacted for 1 hour. The 0.05N ammine silver complex salt aqueous solution used was one in which the pH was adjusted to 11.5 with 30% ammonia water. After the reaction, the mixture was centrifuged and the precipitate was washed with ethanol and dried at 70 to 100 ° C to obtain an antibacterial and antifungal ammine silver montmorillonite intercalation compound. In addition, all reactions were performed at room temperature (20 to 25 ° C.).

(Example 2) Other than using 0.05N ethanolamine silver complex salt aqueous solution,
An antibacterial and antifungal ethanolamine silver montmorillonite intercalation compound was obtained in the same manner as in Example 1.

Example 3 An antibacterial and antifungal triethanolamine silver montmorillonite intercalation compound was obtained in the same manner as in Example 1 except that a 0.05N triethanolamine silver complex salt aqueous solution was used.

Example 4 An antibacterial and antifungal diethylenetriamine silver montmorillonite intercalation compound was obtained in the same manner as in Example 1 except that a 0.05N diethylenetriamine silver complex salt aqueous solution was used.

Example 5 An antibacterial and antifungal triethylenetetramine silver montmorillonite intercalation compound was obtained in the same manner as in Example 1 except that 0.05N triethylenetetramine silver complex salt aqueous solution was used.

(Example 6) An antibacterial and antifungal ammine silver teniolite intercalation compound was obtained in the same manner as in Example 1 except that 2 g of Li-teniolite was used instead of Na-montmorillonite.

(Example 7) An antibacterial and antifungal ethanolamine silver teniolite intercalation compound was obtained in the same manner as in Example 2 except that 2 g of Li-teniolite was used instead of Na-montmorillonite.

(Example 8) An antibacterial and antifungal triethylenetetramine silver teniolite intercalation compound was obtained in the same manner as in Example 5 except that 2 g of Li-teniolite was used instead of Na-montmorillonite.

(Comparative Example 1) 2 g of Na-montmorillonite was gradually added to 40 ml of 0.1 NAgNO ₃ aqueous solution with stirring with a stirrer and reacted for 1 hour.
After the reaction, centrifuge and wash the precipitate with ethanol.
It was dried at -100 ° C to obtain a silver montmorillonite intercalation compound.

Comparative Example 2 A silver teniolite intercalation compound was obtained in the same manner as in Comparative Example 1 except that 2 g of Li-teniolite was used.

Table 1 shows the properties of the intercalation compounds obtained in these examples using only the silver complex salt and the comparative examples using the silver acoion.
As is clear from the comparative examples, when silver ions are inserted between the layers, the color of the intercalation compound becomes black, and the dried ones are very difficult to grind (represented by X in Table 1) or slightly hard to grind. Moreover, since the amount of silver ions eluted is too large (indicated by Δ in Table 1), it is unsuitable as an antibacterial and antifungal agent (indicated by X in Table 1). In the case of the examples according to the present invention, the pulverizability and the antibacterial and antifungal evaluation test are good (represented by a circle in Table 1), and many elution amounts of silver ions can be selected by selecting a ligand. It turns out that

(Example 9) 20 ml of 0.05N ammine silver complex salt aqueous solution and 0.1N ammine copper complex salt 2
0 ml was mixed, and 2 g of Na-montmorillonite was gradually added to a liquid having a pH of 11.5 with 30% ammonia water while stirring with a stirrer and reacted for 1 hour. After the reaction, the mixture was centrifuged and the precipitate was washed with ethanol and dried at 70 to 100 ° C to obtain an antibacterial and antifungal ammine silver / copper montmorillonite intercalation compound.

(Example 10) 0.05 N ammine silver complex salt aqueous solution 13 ml and 0.1 N ammine copper complex salt aqueous solution 39 ml were mixed, and to a liquid having PH of 11.5 with 30% ammonia water, 2 g of Li-teniolite was gradually stirred with a stirrer. Addition was continued for 1 hour. After the reaction, the mixture was centrifuged, and the precipitate was washed with ethanol and dried at 70 to 100 ° C to obtain an antibacterial and antifungal ammine silver / copper teniolite intercalation compound.

(Example 11) 13 ml of 0.05N ammine silver complex salt aqueous solution and 39 ml of 0.1N aluminum nitrate aqueous solution were mixed, and PH was adjusted to 11.5 with 30% ammonia water.
2 g of Li-teniolite was gradually added to the above liquid with stirring with a stirrer and reacted for 1 hour. After the reaction, the mixture was centrifuged, and the precipitate was washed with ethanol and dried at 70 to 100 ° C to obtain an antibacterial and antifungal aluminum / ammine silver teniolite intercalation compound.

Example 12 An ethanolamine silver complex salt was used in place of the ammine silver complex salt.
An antibacterial and antifungal ethanolamine silver / copper teniolite intercalation compound was obtained in the same manner as in Example 10 except that the ethanolamine copper complex salt was used instead of the ammine copper complex salt.

(Example 13) An antibacterial and antifungal triethylenetetramine silver was prepared in the same manner as in Example 10 except that triethylenetetramine silver complex salt was used instead of the ammine silver complex salt and triethylenetetramine copper complex salt was used instead of the ammine copper complex salt. A copper teniolite intercalation compound was obtained.

Table 2 shows the characteristics of the intercalation compounds obtained in these examples using a silver complex salt and a metal complex salt other than silver or a metal ion other than silver. The ∘ mark in Table 2 indicates that the antibacterial and antifungal intercalation compound has a significantly smaller amount of silver ions eluted than the case of using only the silver complex salt.

(Effect of the invention) Since the antibacterial and antifungal intercalation compound and the production method of the present invention are configured as described above, it is possible to control the elution amount of silver ions according to the application of the antibacterial and antifungal, and It also has an economic effect of saving inorganic layered compounds, and is used for a wide range of applications such as paints, fibers, building materials, films, etc. due to its sustainability, averaging, stabilization, safety, and ease of handling of antibacterial and antifungal effects. In particular, it will be a great benefit to be able to apply it widely in the future to realize a healthy living environment.

[Brief description of drawings]

FIG. 1 is a schematic external view showing fine particles of an inorganic layered compound.
FIG. 2 is a diagram schematically showing that fine particles of an inorganic layered compound are gathered to form an inorganic layered compound. FIG. 3 is a diagram showing the interlayer condition of the inorganic layered compound, and FIG. 4 is a diagram schematically showing the interlayer condition as an example of the antibacterial and antifungal interlayer compound according to the present invention. FIG. 5 is a diagram schematically showing the situation when the interlayer is viewed from above as an example of the antibacterial and antifungal interlayer compound according to the present invention. A ... Fine particles of inorganic layered compound 1 ... Crystal layer 2 ... Interlayer 3 ... Negative charge 4 ... Alkali metal ion 5 ... Silver complex salt 6 ... Metal complex salt other than silver or metal ion other than silver 7 ... Lithium ion 8 ... Ammine silver complex salt 9 ... Ammine copper complex salt

Claims (8)

[Claims] 1. An antibacterial and antifungal intercalation compound comprising a silver complex salt supported between layers of an inorganic layered compound. 2. An antibacterial / antifungal intercalation compound comprising a silver complex salt and a metal complex salt other than silver or / and a metal ion other than silver mixed and supported between the layers of the inorganic layered compound. 3. The inorganic layered compound is selected from the group consisting of montmorillonite, bentonite, chlorite, beidellite, hectorite, teniolite, vermiculite, synthetic mica, synthetic smectites and substituted analogues and mixtures thereof. The antibacterial and antifungal intercalation compound according to the above items 1 and 2. 4. The silver complex salt is selected from silver complex salts obtained by reacting at least one selected from ligands that coordinate with silver to form a complex salt with a silver ion. The antibacterial and antifungal intercalation compound according to items 1 and 2. 5. A metal complex salt other than silver is obtained by reacting at least one kind selected from metal ions other than silver with at least one kind selected from a ligand which forms a complex salt with them. The second selected from metal complex salts.
An antibacterial and antifungal intercalation compound according to the item. 6. A metal ion other than silver does not form a complex salt with a ligand of the same kind as a ligand constituting a silver complex salt and / or a complex salt of a metal other than silver, or forms only an unstable complex salt. The antibacterial and antifungal intercalation compound according to claim 2, which is at least one kind selected from ions. 7. An antibacterial and antifungal intercalation compound comprising a silver compound, a solvent, at least one selected from a ligand forming a complex salt with silver, and an inorganic layered compound mixed to carry a silver complex salt between the layers of the inorganic layered compound. Manufacturing method. 8. A silver compound, a solvent, at least one selected from ligands which form a complex salt with silver, at least one selected from metal compounds other than silver, and a ligand which forms a complex salt with them. And / or at least one selected from metal compounds other than silver that does not form a complex salt with all the ligands used in the reaction or only forms an unstable complex salt, and an inorganic layered compound. A method for producing an antibacterial / antifungal intercalation compound, which comprises mixing and supporting a silver complex salt, a complex salt of a metal other than silver, and / or a metal ion other than silver between the layers of an inorganic layered compound.