JP3264040B2 - Antibacterial agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to at least one kind of fungicide selected from silver, copper, zinc, tin, mercury, lead, iron, cobalt, nickel, manganese, cadmium and chromium,
The present invention relates to an antibacterial agent comprising a specific phosphosilicate compound having a metal ion exhibiting antibacterial properties and antialgal properties (hereinafter referred to as antibacterial properties). INDUSTRIAL APPLICABILITY The present invention is used as an antibacterial composition mixed with various binders, or as an antibacterial molded product carried on a carrier such as fiber, film, paper, ceramics and plastic.

[0002]

2. Description of the Related Art Metal ions such as silver, copper, zinc, tin, mercury, lead, iron, cobalt, nickel, manganese, bismuth, barium, cadmium, and chromium are metals having antifungal, antibacterial and algal properties. It has long been known as an ion (hereinafter referred to as an antibacterial metal ion), and in particular, silver ion is widely used as an aqueous silver nitrate solution having a disinfecting action and a bactericidal action. However, the above-mentioned metal ions exhibiting antibacterial properties and the like are often toxic to the human body, and there are various restrictions on the method of use, storage, disposal, and the like, and their uses have also been limited.

In recent years, it has been revealed that a small amount of antibacterial metal ion is sufficient to act on an object to exert antibacterial properties and the like. An organic antibacterial agent supported on a resin or a chelate resin, and an inorganic antibacterial agent having antibacterial metal ions supported on a clay mineral, an inorganic ion exchanger, or a porous body have been proposed.

[0004] Among the above various antibacterial agents, inorganic antibacterial agents are generally higher in safety than organic ones, have a longer lasting antibacterial effect, and are excellent in heat resistance. As one of the inorganic antibacterial agents, antibacterial agents in which alkali metal ions such as sodium ions in clay minerals such as montmorillonite and zeolite are ion-exchanged with silver ions are known. However, since the skeleton structure of the clay mineral itself is inferior in acid resistance, for example, silver ions are easily eluted in an acidic solution, and the durability of the antibacterial effect is not sufficient. Also,
This silver ion is unstable to heat and light exposure,
Since it is easily reduced to metallic silver, in this case, there is a problem that it is easily colored and lacks long-term stability.

[0005] In order to increase the stability of silver ions, zeolite is also known in which silver ions and ammonium ions are supported by coexistence by ion exchange, but the prevention of coloring is not practically sufficient. , The fundamental solution has not been reached. Further, as another inorganic antibacterial agent, there is an antibacterial agent in which an antibacterial metal ion is adsorbed on activated carbon having adsorptivity, but the soluble antibacterial metal ion is physically adsorbed or adhered. Since it is too short, the antimicrobial metal ion is rapidly eluted when brought into contact with moisture, and the durability of the antimicrobial effect is poor.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to exposing to sunlight or a high-temperature atmosphere or contacting with an acidic solution.
An object of the present invention is to provide an antibacterial agent which does not discolor, does not deteriorate antibacterial properties, and can exhibit antibacterial properties for a long time even under severe environments.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, it has been found that a specific phosphosilicate compound carrying an antibacterial metal ion has a very excellent chemical property. The present inventors have found that the present invention has good stability and antibacterial properties for a long time, and has completed the present invention.

That is, the antibacterial agent of the present invention is characterized by comprising a compound represented by the following general formula [1]. _{M a A (1 + b-} pa) / q B 2 Si b P (3-b) O 12 (1) (M is silver, copper, zinc, tin, mercury, lead, iron, cobalt, nickel, manganese, A is at least one kind of metal ion selected from barium, cadmium and chromium, A is at least one kind of ion selected from alkali metal ion, alkaline earth metal ion, hydrogen ion and ammonium ion, B is titanium, At least one kind of tetravalent metal ion selected from zirconium and tin,
a and b are both positive numbers, b is a number satisfying 0 <b < 3, p is a valence of M, q is a valence of A, and p, a and b are pa <1 + b. )

The metal “M” in the general formula [1] is
Specific antimicrobial metal ions listed above. Each of the listed metal ions is useful as a metal having fungicide, antibacterial and antialgal properties, and among these, silver ions are preferred. This is because they have excellent safety and antibacterial properties.

The amount of the metal "M" carried (the value of a in the above general formula [1]) is preferably large in order to exhibit antibacterial properties and the like.
01 to 0.5 (more preferably 0.01 to 0.5). If it is less than 0.001, it may be difficult to exert antibacterial properties and the like for a long time, and if it exceeds 0.5, it is not preferable in terms of economy. In particular, this is 0.01-
A range of 0.5 is more preferable because the balance between antibacterial properties and economic efficiency is excellent.

"A" in the general formula [1] is at least one ion selected from alkali metal ions, alkaline earth metal ions, hydrogen ions and ammonium ions. The alkali metal ion is preferably a lithium ion, a sodium ion or a potassium ion, and the alkaline earth metal ion is preferably a magnesium ion or a calcium ion. . Preferred ions as A are a hydrogen ion, a lithium ion, a sodium ion and an ammonium ion in view of the stability of the compound and availability at a low cost.
Sodium ions are more preferred.

"B" in the above general formula [1] is at least one kind of tetravalent metal ion selected from titanium, zirconium and tin, and considering the safety of the compound,
Zirconium or titanium is particularly preferred.

The following are specific examples of the present antibacterial agent. Ag _0.01 Li _1.39 Zr ₂ Si _0.4 P _2.6 O ₁₂ Ag _0.05 Na _1.75 Ti ₂ Si _0.8 P _2.2 O ₁₂ Ag _0.1 Li _2.2 H _0.3 Zr ₂ Si _1.6 P _1.4 O ₁₂ Ag _0.3 Na _2.5 H _0.4 Ti ₂ Si _2.2 P _0.8 O ₁₂ Ag _0.5 Na _2.7 H _0.6 Zr ₂ Si _2.8 P _0.2 O ₁₂ and the amount of A in each of the above formulas was adjusted so that the charge amount was the same as the charge amount of silver ions per mole of the compound.
Compounds in which g is substituted with at least one selected from Zn, Mn, Ni, Pb, Hg, Sn and Cu.

The antibacterial agent of the present invention generally has the following general formula [2]
And a phosphorus silicate compound [also referred to as compound (2). Is impregnated with a solution containing a predetermined antibacterial metal ion (M) such as silver, so that part or all of the A ion is exchanged for the metal (M) ion, and then dried and, if necessary, calcined. Manufactured. A _{(1 + b) / q} B ₂ Si _b P _(3-b) O ₁₂ [2] Here, A, B, b and q are the same as those represented by the above general formula [1]. is there. As the compound (2), a NASICON-type compound having the above chemical composition and known as a superionic conductor can be used, and any of an amorphous or crystalline compound can be used. Crystalline compounds are preferred because of less discoloration upon exposure.

Specific examples of this compound include the following. _{Li 1.4 Zr 2 Si 0.4 P 2.6} O 12 Li 2.4 Ti 2 Si 1.4 P 1.6 O 12 Li 3.5 Zr 2 Si 2.5 P 0.5 O 12 Na 1.5 Zr 2 Si 0.5 P 2.5 O 12 Na 1.8 Ti 2 Si 0.8 P 2.2 O 12 _{Na 2.6 Zr 2 Si 1.6 P 1.4} O 12 Na 3.8 Zr 2 Si 2.8 P 0.2 O 12

The compound (2) can be obtained by a synthesis method using a conventionally used sol-gel method, a hydrothermal synthesis method, a synthesis method by a solid phase reaction involving calcination, or the like. Specific examples of this synthesis method are shown below. That is, sodium carbonate, zirconium oxide, ammonium hydrogen phosphate and silicon dioxide were mixed at a predetermined ratio for each raw material, and the mixture was mixed at about 170 ° C.
For 4 hours. Subsequently, the mixture is fired at about 900 ° C. for about 4 hours, and then further fired at about 1200 ° C. for about 12 hours to obtain a phosphosilicate compound. The ratio of each element in this compound can be adjusted by changing the ratio of each raw material.

The ion exchange reaction for supporting the antibacterial metal ion on the compound (2) may be performed according to a conventionally known method. For example, an aqueous nitric acid solution containing an antibacterial metal ion at an appropriate concentration may be used. By immersing the phosphorus silicate compound in this, the process proceeds easily. The amount of the antibacterial metal ion to be carried is determined by adjusting the concentration of the antibacterial metal ion in the aqueous solution in which the phosphosilicate compound is immersed, the time required for immersion in the aqueous solution or the immersion temperature, etc., to obtain the required properties and operating conditions. It can be adjusted appropriately according to the conditions.

A preferred method for introducing a hydrogen ion as "A" in the general formula [2] is to use a phosphosilicate compound having an ion other than a hydrogen ion such as sodium by using an acid such as hydrochloric acid, sulfuric acid or nitric acid. Immersion treatment. Also, ammonium ions and other metal ions can be introduced by immersion treatment in a solution containing the ions to be introduced.

In the present invention, the compound (2) can be used as an antibacterial agent after carrying an antibacterial metal ion, washing with water and heating (drying) in a temperature range of 70 to 130 ° C. Alternatively, if necessary, a baked product obtained by further heating (baking) at a high temperature can be used as an antibacterial agent. By this calcination, the chemical and physical stability of the antibacterial agent is remarkably improved, and an antibacterial agent having more excellent weather resistance can be obtained. The firing conditions, for example, firing temperature, firing time, heating rate and cooling rate are not particularly limited, and can be appropriately adjusted in consideration of the capacity of the firing furnace, productivity, and the like. 500 to 1300 ° C
(Preferably 600-800 ° C.), and firing time is 1-20
Time.

The form of use of the antibacterial agent is not particularly limited.
Depending on the application, it can be mixed with other components as appropriate or combined with other materials. For example, it can be used in various forms such as powder, powder-containing dispersion, powder-containing particles, powder-containing paint, powder-containing fiber, powder-containing paper, powder-containing film or powder-containing aerosol. Further, if necessary, various additives or materials such as a deodorant, a flame retardant, an anticorrosion, a fertilizer, and a building material can be used in combination.

[0021]

SUMMARY OF] The antimicrobial _{agent, M a A (1 + b} -pa) / q B 2 Si b P (3-b)
As can be seen from having an O ₁₂ composition, the structure and composition do not change even after heating at 500 to 1300 ° C. since the phosphorus silicate compound has a skeleton, and the skeleton structure changes even in an acidic solution. Is not seen. Furthermore, in this antibacterial agent,
A predetermined antibacterial metal ion is firmly supported on the phosphosilicate compound. Therefore, this antibacterial metal ion is not easily eluted even in an acidic solution. As described above, the antibacterial agent is stable against acids, heat and light, does not discolor at all under severe environments where it is exposed to sunlight or a high-temperature atmosphere or is brought into contact with an acidic solution, Even if used, the weather resistance and antibacterial properties do not deteriorate. Therefore,
This antibacterial agent is used for processing and storage when obtaining various molded products,
Furthermore, unlike the conventional antibacterial agents, there is no restriction on the heating temperature or the light-shielding conditions during use.

[0022]

EXAMPLES In the following Examples and Comparative Examples, predetermined antibacterial agents were prepared as shown below, and subjected to a weather resistance test, an antibacterial test and an acid resistance test. Example 1 (1) Preparation of antibacterial agent First, a phosphosilicate compound was prepared as follows. That is, predetermined amounts of sodium carbonate, zirconium oxide, ammonium hydrogen phosphate, and silicon oxide are mixed so as to have the following composition after firing, and fired at 170 ° C. for 4 hours, and then fired at 900 ° C. for 4 hours. , And 1200 ° C
For 12 hours. This product is crushed with a crusher,
A compound represented by the following composition formula [3] [hereinafter referred to as compound (3). ] Was obtained. In addition, this chemical composition is obtained by composition analysis.
It is obtained by determining the content of each ion in the compound and estimating the composition. The same applies to the following. _{Na 1.8 Zr 2 Si 0.8 P 2.2} O 12 (3)

Next, 20 g of the powder of the compound (3), 0.944 g of silver nitrate, and 100 g of a 0.1N aqueous nitric acid solution were placed in a polyethylene sample bottle and shaken at 40 ° C. for 2 hours. Thereafter, the slurry was filtered, washed with water, dried, and pulverized to obtain an antibacterial agent having the following composition formula (a) (hereinafter referred to as antibacterial agent a). Ag _0.12 Na _1.45 H _0.23 Zr ₂ Si _0.8 P _2.2 O ₁₂ (a)

(2) Performance Evaluation The antibacterial agent a was subjected to the following weather resistance test, antibacterial test and acid resistance test, and the results are shown in Table 1. Weather resistance test A plate having a thickness of 3 mm was prepared by adding 5% by weight of the antibacterial agent a to a commercially available polyethylene resin, and a weather resistance test was performed using this plate as a test piece. In this test,
One cycle was performed by irradiating ultraviolet rays at 60 ° C. for 1 hour, and then adjusting to a humidity of 9
It consisted of a step of leaving at 0% for 1 hour at 40 ° C., and was repeated three cycles. And the colors (L, a, b) before and after the test
Colorimeter [Nippon Denshoku Industries Co., Ltd. colorimeter "SZ-Ｚ8"
0 "] to evaluate the weather resistance.

Antibacterial activity test The minimum inhibitory concentration of antimicrobial agent a against Escherichia coli (MIC: the minimum concentration of an antimicrobial agent capable of inhibiting the growth of a subject) was measured by the standard method of the Japanese Society of Chemotherapy. Acid resistance test 10% by weight of antimicrobial agent a was added to a 4% by weight aqueous acetic acid solution (pH 3) and allowed to stand for 4 hours. Then, the antimicrobial agent was separated by filtration, and the elution amount of silver ions in the filtrate was measured by atomic absorption spectroscopy. It was measured with a meter.

Example 2 The antimicrobial agent a obtained in Example 1 was calcined at 700 ° C. for 4 hours.
An antibacterial agent b was prepared, and a weather resistance test, an antibacterial test and an acid resistance test were carried out in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 1 An antibacterial zeolite according to Comparative Example 1 was prepared as described below, and a weather resistance test, an antibacterial test and an acid resistance test were carried out in the same manner as in Example 1, and the results were obtained. Also shown in Table 1. A-type zeolite (composition: 0.94Na ₂ O · A
The _{l 2 O 3 · 1.92SiO 2 ·} xH 2 O), was added to the aqueous silver nitrate solution, and the mixture was stirred for 5 hours at room temperature, the slurry is filtered,
The product was washed with water, dried and pulverized to obtain an antibacterial agent c having the following composition formula (c). 0.03Ag ₂ O ・ 0.8Na ₂ O ・ Al ₂ O ₃・ 1.9SiO ₂・ nH ₂ O （c）

Comparative Example 2 The antibacterial agent c obtained in Comparative Example 1 was calcined at 700 ° C. for 4 hours.
An antibacterial agent d was prepared, and an antibacterial test was performed on it in the same manner as in Example 1. The results are shown in Table 1.

[0029]

[Table 1]

(3) Effects of Examples and Comparative Examples According to the results shown in Table 1, the antibacterial agent c of Comparative Example 1 showed a large color change (coloring was observed) before and after the weather resistance test. Antibacterial agent a of Examples 1 and 2 according to the present invention
In (b) and (b), the change was remarkably small as compared with Comparative Example 1, indicating that the weather resistance was remarkably excellent. In addition, the change after firing (Example 2) is smaller than that of the unfired dried product (Example 1), indicating that the weather resistance is further improved by firing.

As for the antibacterial activity, the minimum inhibitory concentration (MIC) against Escherichia coli was 125 ppm for both antibacterial agents a and b (Examples 1 and 2), and Comparative Example 1
And 2 (250 ppm, 250 ppm, respectively)
(0 ppm or more). In particular, the antibacterial property of the baked antibacterial agent d of Comparative Example 2 (MIC: 2500
ppm or more) is extremely bad. However, in Examples 1 and 2, almost the same performance was exhibited, and even when high-temperature heating was performed, the performance did not decrease, indicating that heating was more stable than in the comparative example. Further, with respect to acid resistance, Examples 1 and 2
In the antibacterial agents a and b, there is almost no elution of the acid, but the antibacterial agent of Comparative Example 1 is as large as 5 ppm, indicating that the stability by the acid is poor.

As described above, the product of the present invention (Examples 1 and 2)
, The antibacterial properties and the acid resistance were almost the same, and unlike the comparative example, no deterioration in performance was shown even when heating was performed at a high temperature. Therefore, in Examples 1 and 2, the structure (skeleton) and composition did not change even by heating, while it is considered that some change occurred in the comparative example.

[0033]

The antimicrobial agent of the present invention does not discolor and does not deteriorate its antibacterial properties even under severe environments where it is exposed to sunlight or a high-temperature atmosphere or is contacted with an acidic solution. , Antibacterial properties and anti-algal properties can be exhibited for a long time. Therefore, this antibacterial agent is used for textiles such as work clothes, medical clothing, medical bedding, sports clothes, bandages, fishing nets, curtains, carpets, underwear, air filters, etc. Packaging films, medical films, synthetic leather and other membranes,
Paints such as sterilizer wall paint, antiseptic paint, mold paint,
It is extremely useful for applications such as powders for agricultural soils and liquid compositions such as shampoos.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hideki Kato 1 at Funami-cho, Minato-ku, Nagoya-shi, Aichi Prefecture, Nagoya Research Institute, Toagosei Chemical Industry Co., Ltd. (56) References A) JP-A-5-32512 (JP, A) JP-A-5-32407 (JP, A) JP-A-4-338138 (JP, A) JP-A-4-338129 (JP, A) JP-A-4 -273803 (JP, A) JP-A-3-83906 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A01N 59/26 C08J 5/18

Claims (1)

(57) [Claims] 1. An antibacterial agent comprising a compound represented by the following general formula [1]. _{M a A (1 + b-} pa) / q B 2 Si b P (3-b) O 12 (1) (M is silver, copper, zinc, tin, mercury, lead, iron, cobalt, nickel, manganese, A is at least one kind of metal ion selected from barium, cadmium and chromium, A is at least one kind of ion selected from alkali metal ion, alkaline earth metal ion, hydrogen ion and ammonium ion, B is titanium, At least one kind of tetravalent metal ion selected from zirconium and tin,
a and b are both positive numbers, b is a number satisfying 0 <b < 3, p is a valence of M, q is a valence of A, and p, a and b are pa <1 + b. )