JPH0684248B2 - Antibacterial amorphous aluminosilicate - Google Patents

Description

The present invention relates to an amorphous aluminosilicate (hereinafter referred to as AAS) having an antibacterial effect against various bacteria and fungi and an antibacterial containing the antibacterial AAS. Resin composition.

[Conventional technology]

Heretofore, as an inorganic antibacterial agent, for example, activated carbon carrying silver (JP-A-49-61950) has been known, and as an organic antibacterial and antifungal agent, for example, N- (fluorodichloromethylthio) -phthalimide has been known. However, the former (inorganic type) has a problem that silver ions are quickly eluted into a solution and an antibacterial effect cannot be permanently obtained. On the other hand, the latter (organic type) may not show antibacterial action depending on the type of fungus (lacks versatility depending on the type of fungus), and even the type with heat resistance is 150 to 300 ° C. However, when kneaded into the resin, it decomposes or evaporates, and the effect is reduced.

So-called antibacterial zeolite and antibacterial AAS in which an antibacterial component is supported on zeolite or AAS have been developed as a solution to the problems of the conventional antibacterial agents (Japanese Patent Publication No. 61-22977, JP-A-61-22977). No. 60-181002).

[Problems to be solved by the invention]

The above-mentioned antibacterial AAS is an excellent antibacterial agent which is surely excellent in durability of antibacterial activity when left in water or air and does not deteriorate when kneaded into resin.

However, there is a problem that the resin in which the antibacterial AAS is kneaded is discolored and the degree of discoloration is increased with time.
The discoloration does not change the antibacterial properties of AAS. However, the antibacterial A
The discoloration of a resin molded product containing AS can significantly reduce the value of the product using it.

Therefore, an object of the present invention is that even when added to a resin, the resin does not discolor, and the degree of discoloration does not increase with time, and has excellent antibacterial properties equivalent to conventional antibacterial AAS. To provide antibacterial AAS.

[Means for solving problems]

The present invention relates to an antibacterial amorphous aluminosilicate in which some or all of the ion-exchangeable ions in the amorphous aluminosilicate are replaced with antibacterial metal ions and ammonium ions.

The present invention will be described in detail below.

In the present invention, AAS (amorphous aluminosilicate) used as a raw material is not particularly limited, and conventionally known one can be used as it is. AAS is generally represented by the compositional formula xM ₂ O.Al ₂ O ₃ .ySiO ₂ .zH ₂ O, where M is generally an alkali metal element (eg sodium, potassium, etc.). Further, x, y, and z represent the molar ratio of metal oxide, silica, and crystal water, respectively. Unlike crystalline aluminosilicates, which are called zeolites, AAS is an amorphous substance that does not show a diffraction pattern in X-ray diffraction analysis, and the synthesis process produces extremely fine zeolite crystals of several tens of amperes. However, it is considered to have a structure in which an amorphous substance in which a plurality of SiO ₂ , Al ₂ O ₃ , M ₂ O and the like are combined is attached to the surface thereof. AAS is generally produced by using an aluminum salt solution, a silicon compound solution and an alkali metal salt solution at a predetermined concentration of 60%.
It is produced by reacting in a low temperature range of ℃ or less and washing with water before crystallization proceeds. As a manufacturing method, for example, Japanese Patent Publication No.
099, JP-A-55-162418 and the like.

The antibacterial AAS of the present invention is ion-exchanged with ammonium ions in addition to antibacterial ions. By performing ion exchange with ammonium ions, discoloration of AAS itself and discoloration of the resin when added to the resin (including discoloration over time) can be effectively prevented.

Examples of antibacterial metal ions include silver, copper, zinc, mercury,
Mention may be made of tin, lead, bismuth, cadmium, chromium or thallium ions, preferably silver, copper or zinc ions.

Of the antibacterial metal, the amount of silver added is 0.1 to 50%, preferably
From 0.5 to 5% is suitable from the viewpoint of showing excellent antibacterial activity. In addition, copper, zinc, mercury, tin, lead,
It is preferable to contain 0.1 to 10% of one or more metals selected from bismuth, cadmium, chromium and thallium.

Further, the antibacterial AAS of the present invention contains ammonium ion by ion exchange in addition to the above antibacterial metal. Ammonium ion can be contained up to 15% in AAS, but the content of ammonium ion in AAS is 0.5%.
-5%, preferably 0.5-2% is suitable from the viewpoint of effectively preventing discoloration of the AAS and the resin in which the AAS is kneaded. In the present specification,% means 11
It refers to the weight percentage on a dry basis at 0 ° C.

The method for producing the antibacterial AAS of the present invention will be described below.

The antibacterial AAS of the present invention can be produced, for example, by the following method.

The AAS obtained by the known method is suspended in, for example, water, and the obtained AAS slurry is mixed with an antibacterial metal ion and ammonium ion-containing aqueous solution to obtain antibacterial properties such as silver ion, copper ion, and zinc ion. When AAS is contacted with a mixed aqueous solution containing metal ions and ammonium ions,
The ion exchangeable ions in AS are replaced with the above ions. Contact at 5 to 70 ° C, preferably 40 to 60 ° C for 1 to 24
It can be carried out by a batch method or a continuous method (for example, a column method), preferably for 10 to 24 hours. The pH of the mixed aqueous solution is adjusted to 3 to 12, preferably 3 to 6. By this adjustment, precipitation of silver oxide or the like on the AAS surface or in the pores can be prevented, which is preferable. Each of the ions in the mixed aqueous solution is usually supplied as a salt. For example, silver ions are silver nitrate, silver sulfate, silver perchlorate, silver acetate, diammine silver nitrate, diammine silver sulfate, etc., and copper ions are copper nitrate (II), copper perchlorate, copper acetate, potassium tetracyanocuprate, Zinc ions such as copper sulfate, zinc nitrate (II), zinc sulfate, zinc perchlorate, zinc thiocyanate, zinc acetate, etc., mercury ions, mercury perchlorate, mercury nitrate, mercury acetate, etc., tin ions, sulfuric acid, etc. Lead ions such as tin, lead sulfate, lead nitrate, etc.
Bismuth ions include bismuth chloride, bismuth iodide, etc.
Cadmium ions are cadmium perchlorate, cadmium sulfate, cadmium nitrate, cadmium acetate, etc.Chromium ions are chromium perchlorate, chromium sulfate, ammonium sulfate chromium, chromium nitrate, etc.Thallium ions are thallium perchlorate, thallium sulfate, Thallium nitrate, thallium acetate, etc. can be used.

Examples of ammonium ions that can be used include ammonium nitrate, ammonium sulfate, ammonium acetate, ammonium perchlorate, ammonium thiosulfate, and ammonium phosphate.

The content of ammonium ions and the like in AAS can be appropriately controlled by adjusting the concentration of each ion (salt) in the mixed aqueous solution. For example, when the antibacterial AAS contains ammonium ions and silver ions, the ammonium ion concentration in the mixed aqueous solution is 0.1 M / to 1.7 M /, and the silver ion concentration is 0.01 M / to 0.30 M /, as appropriate. An antibacterial AAS having an ammonium ion content of 0.4 to 4% and a silver ion content of 0.5 to 6% can be obtained.
When the antibacterial AAS further contains copper ions and zinc ions, the copper ion concentration in the mixed aqueous solution is 0.05 M / ~.
An antibacterial AAS having a copper ion content of 1 to 8% and a zinc ion content of 1 to 8% can be obtained by setting 0.4 M / and the zinc ion concentration to 0.05 M / to 0.4 M /.

In the present invention, an ion exchange can also be carried out by using an aqueous solution containing each ion alone in addition to the mixed aqueous solution as described above and sequentially bringing each aqueous solution into contact with AAS. The concentration of each ion in each aqueous solution can be determined according to the concentration of each ion in the mixed aqueous solution.

The AAS after the ion exchange is thoroughly washed with water and then dried. Drying at 105 ℃ ~ 115 ℃ under normal pressure, or reduced pressure (1 ~ 30
torr) at 70 ° C to 90 ° C.

Ion exchange of ions or organic ions without a suitable water-soluble salt such as tin or bismuth can be carried out by using a solution of an organic solvent such as alcohol or acetone so that a sparingly soluble basic salt is not deposited.

The antibacterial activity of the antibacterial AAS of the present invention thus obtained is
It can be evaluated by measuring the minimum inhibitory concentration (MIC) against various general bacteria, fungi and yeasts.

The following bacteria can be used for the test.

Bacillus cereus var mycoides [ATCC 11778 (malt)] Escherichia coli [Esherichia coli, IFO 3301] Pseudomonas aeruginosa, IIDP-1] Staphylococcus aureus [Staphylocus aureus] ATCC 6538P Strepto coccus faecalis, RATCC 8043 Aspergillus niger IFO 4407 Aureobasidium pullulans IFO 6353 Chematoum globosum 6205P Gliocladium virens IFO 6355] Penicillium funiculosum IFO 6345 Candida albicans IFO 1594 Saccharomyces cerevisiae IFO 1950 Minimal stunting concentration After the test smear culturing for inoculation cell solution to plate medium supplemented with the test sample antimicrobial AAS optionally concentration, the minimum inhibitory concentration with the lowest concentration at which growth is inhibited.

The present invention also provides an antibacterial resin composition containing the above antibacterial AAS and a resin. Examples of the resin include polyethylene, polypropylene, vinyl chloride, ABS resin, nylon, polyester, polyvinylidene chloride, polyamide,
Polystyrene, polyacetal, polyvinyl alcohol, polycarbonate, acrylic resin, fluororesin, polyurethane elastomer, polyester elastomer,
There may be mentioned thermoplastic or thermosetting resins such as phenolic resins, urea resins, melamine resins, unsaturated polyester resins, epoxy resins, urethane resins, rayon, cubra, acetates, triacetates, vinylidene, natural and synthetic rubbers. The antibacterial resin composition of the present invention,
The antibacterial AAS can be obtained by directly kneading the above resin or coating the surface thereof. From the viewpoint of adding antibacterial, mildewproof and algaeproof functions to the above resins,
It is suitable to include 80%, preferably 0.1-80% antibacterial AAS. The MIC of the antibacterial resin composition can be performed in the same manner as described above. Furthermore, from the viewpoint of substantially preventing discoloration of the resin, the content of the antibacterial AAS is 0.1-
It is preferably 3%.

The antibacterial AAS of the present invention can be used in various fields.

In the water system field, it can be used as a water purifier, a cooling tower water, and an antibacterial and algae agent for various kinds of cooling water, and also a cut flower prolongation agent.

In the field of paints, oil paints, lacquers, varnishes, alkyl resins, aminoalkyd resins, vinyl resins, acrylic resins, epoxy resins, urethane resins, water-based, powder-based, chlorinated rubber-based, phenol-based, etc. It is possible to add antibacterial / mildew-proof / algae-proof functions to the coating film by directly mixing it with the paint or coating it on the surface of the coating film. In the field of construction, it is possible to add antibacterial, antifungal, and algaeproof functions by mixing with joint materials, wall materials, tiles, or the like or coating them.

In the papermaking field, it is possible to add antibacterial and antifungal functions to wet papers, paper packaging materials, cardboards, liners, and freshness-keeping papers by adding or coating them, and especially papermaking. It can also be used as a slime control agent in the field.

INDUSTRIAL APPLICABILITY The antibacterial AAS of the present invention is not limited to the above-mentioned various fields, but can be used in all fields in which it is necessary to prevent the generation and growth of microorganisms such as general bacteria, fungi and algae.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Reference example Aluminum hydroxide 19.4 kg in sodium hydroxide 49% solution
After adding to 22.3 kg and heating and dissolving, add water 34.7 and add 30 ℃
It was maintained at (solution I). On the other hand, water 25.5 was added to sodium silicate 42.0 kg and the temperature was maintained at 30 ° C (solution II). Liquid I and
Solution II was poured into a reaction tank containing a solution (solution III) in which water 21.3 was added to 4.1 kg of sodium hydroxide 49% solution. After the above operation, the temperature was maintained at 50 ± 2 ° C. with stirring and the reaction was carried out for 30 minutes. The product was filtered and the solid phase component was washed with warm water to remove excess alkali. Further dried at 100 ℃,
I got a sample. This sample has a chemical composition ratio of Na ₂ O: Al ₂
O ₃ : SiO ₂ = 0.93: 1: 2.55, which was an amorphous aluminosilicate in which no diffraction peak was observed by X-ray diffraction analysis.

Example 1 (Preparation of antibacterial AAS) In the composition ratio of xNa ₂ O: Al ₂ O ₃ : ySiO ₂ obtained in Reference Example, x was 0.5-1.
3, AAS with y of 1.3-10 was used. 1 kg of these AAS was collected, suspended in 2.3 water, and a 0.05N nitric acid aqueous solution was added to it.
Dropping at a dropping rate of 100 ml / 30 minutes, and the prescribed pH value (3 to 7)
Adjusted to. Next, 3.5 was added to the slurry for ion exchange in a mixed aqueous solution of a predetermined concentration of antibacterial metal salt. This reaction was stirred at room temperature to 60 ° C for 10 to 24 hours to reach an equilibrium state. After the ion exchange was completed, the AAS phase was filtered and washed with room temperature water or warm water until the excess silver ions in the AAS phase disappeared. Next, the sample was heated and dried at 110 ° C. to obtain 20 kinds of samples. AAS used and 0-1 to 6-7 obtained
The data for the antibacterial AAS sample of is shown in Table 1.

Only sample Nos. 6-7 were ion-exchanged in the alcohol solution.

Example 2 (Discoloration test) A heat-dried antibacterial AAS sample was kneaded into a resin at a kneading amount of 1 wt% and then injection-molded (residence time 2 minutes) to obtain a sample (piece size: 7.3 cm x 4.4). cm x 2 mm). The color of the sample immediately after injection molding and the sample outdoors at 10 and 3
After irradiating with sunlight for a day, put each sample on white Kent paper (L ^* a ^* b ^* 93.1, -0.7, -0.5) and use Minolta color difference meter CR-100 type (using D ₆₅ rays). It was measured using. The results are shown in Table 2 and FIGS. 1 to 7.

(Resin) Nylon: Mitsubishi Kasei Novamid 1010J Polypropylene (PP): Ube Industries J-109G Low Density Polyethylene (LDPE): Asahi Kasei Suntech F
-1920 High Density Polyethylene (HDPE): Suntech HD made by Asahi Kasei
S-360 Polystyrene (PS): Dainippon Ink GH9600 ABS resin: Denki Kagaku GTR-10 Polyvinyl chloride (PVC): Denki Kagaku B-3050F2 (D
OP 60 parts added) Discoloration when UV irradiation with antibacterial AAS (Table 3)
And the color change when heat-treated (Table 4) was measured. Antibacterial
The color of AAS itself is antibacterial in glass petri dish (150φ)
AAS was measured by vibrating and filling it to a height of 2 cm.

Example 3 (antibacterial activity test) Evaluation of antibacterial activity was carried out by the following method.

As a test strain, Aspergillus niger (Aspergillu
s niger) IFO 4407 (mold), Candida albicans IFO 1594 (yeast), Pseudomonas aeruginosa IID P
-1 (Gram-negative general bacteria) and Staphylococcus
Four types of Aureus (Staphylococcus aureus) ATCC 6538P (Gram-positive general bacteria) were used.

Enrichment medium is for bacteria: Mueller-Hinton Broth (Difc
o), for mold: potato dextrose agar medium (Eiken), for yeast: Yeast Morphology Agar (Difco). Sensitivity medium for bacteria: Mueller-Hinton Med
ium (Difco), for mold and yeast: Sabouraud agar medium (Eiken) was used.

The plate for sensitivity measurement was prepared as follows.

Prepare a dilution step suspension of each sample with sterilized purified water, add 1/9 amount of the medium to the sensitivity measurement medium that became 50 to 60 ° C after dissolution, mix well and dispense into a petri dish. Then, it was solidified to obtain a plate for sensitivity measurement.

Preparation of bacterial solution for inoculation is for bacteria: Inoculate test medium that has been subcultured into the medium for enrichment, and dilute with the medium for enrichment so that the number of cells after culture is 10 ⁶ / ml and use did.

For mold: Inoculate the culture medium for enrichment with the subcultured test strain, and sterilize conidia formed after culture to about 10 ⁶ / ml 0.05%
It was suspended in a polysorbate 80 solution to give a bacterial solution for inoculation.
For yeast: A test strain that was subcultured in a culture medium for inoculation was inoculated, and the microbial cells formed after culturing were suspended in sterile physiological saline at about 10 ⁶ / ml to give an inoculum solution.

The culture was carried out as follows.

The inoculum bacterial solution was smeared on a susceptibility measuring plate with a nichrome wire loop (internal diameter of about 1 mm) for about 2 cm, and bacteria were cultured at 37 ° C for 18 to 20 hours and fungi at 25 ° C for 7 days. After the culture for a predetermined time, the determination was made as the minimum inhibitory concentration based on the concentration at which the growth was inhibited.

The results obtained are shown in Table 5.

[Effects of the Invention] According to the present invention, an antibacterial AAS is provided, which does not cause discoloration of the resin over time even when added to a resin, and has excellent antibacterial properties equivalent to those of conventional antibacterial AAS. It

[Brief description of drawings]

FIG. 1 to FIG. 7 are graphs showing the relationship between the L ^* sample / L ^* blank and the elapsed days to show the change over time in the color of the resin in which the antibacterial AAS is kneaded.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location A61K 33/30 8314-4C 33/34 8314-4C 33/38 8314-4C (56) References Special Kai 62-70221 (JP, A)

Claims (5)

[Claims] 1. An antibacterial amorphous aluminosilicate in which a part or all of the ion-exchangeable ions in the amorphous aluminosilicate are replaced with antibacterial metal ions and ammonium ions. 2. The antibacterial metal ion is silver, copper, zinc, mercury,
The antibacterial amorphous aluminosilicate according to claim (1), which is an ion of at least one metal selected from the group consisting of tin, lead, bismuth, cadmium, chromium and thallium. 3. The antibacterial amorphous aluminosilicate according to claim (2), wherein the antibacterial metal ion is an ion of silver, copper or zinc. 4. An antibacterial resin composition containing an antibacterial amorphous aluminosilicate in which a part or all of the ion-exchangeable ions in the amorphous aluminosilicate are replaced with antibacterial metal ions and ammonium ions and a resin. 5. The resin is polyethylene, polypropylene, vinyl chloride, ABS resin, nylon, polyester, polyvinylidene chloride, polyamide, polystyrene, polyacetal, polyvinyl alcohol, polycarbonate, acrylic resin, fluorine resin, polyurethane elastomer,
It is at least one resin selected from the group consisting of polyester elastomer, phenol resin, urea resin, melamine resin, unsaturated polyester resin, epoxy resin, urethane resin, rayon, cupra, acetate, triacetate, vinylidene, natural rubber and synthetic rubber. The composition according to claim (4).