JPS60100504A - Antibacterial composition and its production - Google Patents

Abstract

PURPOSE:To provide a calcined antibacterial composition composed of the system of an antibacterial metal, a carbonate and a zeolite and optionally containing a binder, and having excellent mechanical strength, water resistance, heat resistance and the retainability of the antibacterial activity. CONSTITUTION:A three-component mixture consisting of (A) a carbonate (preferably an alkaline earth metal carbonate), (B) a zeolite (preferably a thermally stable zeolite, A-type zeolite, X-type zeolite, etc. having granular or powdery form) and (C) an antibacterial metal (Zn, Cu or Ag, or their mixture), is added with a binder to reinforce the binding force between the particles. The obtained mixture is formed to a desired form by wet-forming, dried, and calcined at a temperature above the thermal decomposition initiation temperature of the carbonate and below the thermal decomposition initiation temperature of the zeolite, to obtain the objective antibacterial composition. The content of the metal in the calcined product is preferably 0.001-20% for Ag, >=0.04% for Zn and >= about 0.03% for Cu.

Description

DETAILED DESCRIPTION OF THE INVENTION BACKGROUND OF THE INVENTION A. Technical field to which the invention pertains The present invention relates to an antibacterial composition and a method for producing the same. The present invention relates to a novel antibacterial composition that has excellent mechanical strength, water resistance, heat resistance, and ability to retain antibacterial activity, and a method for producing the same.

It is known that metal ions, zinc ions, copper ions, silver ions, etc. have antibacterial properties. For example, silver ions are widely used in the form of silver nitrate aqueous solutions as disinfectants and sterilizers, but when used in solution form, it is inconvenient to handle, and its uses are naturally limited.

On the other hand, it has also been proposed that silver or the like be retained in activated carbon, alumina, or silica gel-based adsorbent materials, and then placed in a container or packed into a tower of an appropriate shape for use in sterilizing liquids. However, the latter case has drawbacks in terms of the retention capacity of the antimicrobial metal for the adsorbed substances and its leakage into the liquid phase. For example, when an aqueous silver nitrate solution is brought into contact with activated carbon to retain silver in the activated carbon phase, increasing the concentration of silver nitrate in the aqueous solution phase will increase the amount of silver adsorbed to the activated carbon phase, but due to crosstalk such as silver adsorption, However, there is clearly a limit to the amount of silver that can be adsorbed. Additionally, as the amount of silver retained in the activated carbon phase increases, the tendency for solid phase silver to leak out prematurely or to leak out in an excessive amount increases when a solution is brought into contact with such silver-containing activated carbon. However, there is a phenomenon in which the amount of silver eluted into the sterilizing solution ultimately exceeds the permissible amount. In order to prevent such silver elution as much as possible, for example, silver-containing activated carbon intended for sterilization with an iron content suppressed to about 6 pP1 is commercially available. However, from the viewpoint of long-term use, the bactericidal effect of such bactericides is not necessarily satisfactory. The regulations for silver are below I)I)b in the United States Public Health Service, below 100 ppb in West Germany, and below 200 ppb in Switzerland.

Judging from such regulated plants, when using silver-containing bactericidal agents, it is urgent to minimize the leakage of silver into the solution and maximize the bactericidal effect over a long period of time.

Summary of the Invention As a result of extensive research aimed at improving commercially available disinfectants, the present inventor has discovered that an antibacterial composition containing a composite of antibacterial metals, carbonates, and zeolites has high mechanical strength and is water resistant. The present invention was based on the discovery that it has excellent antibacterial properties and has many advantages over known bactericidal agents in terms of antibacterial activity and durability of its effects.

Accordingly, it is a principal object of the present invention to provide an antimicrobial composition consisting essentially of an antimicrobial metal-carbonate-zeolide.

Another object of the present invention is the antibacterial metal-carbonate-zeolite
An object of the present invention is to provide an antimicrobial composition consisting essentially of a binder.

Another object of the present invention is the antibacterial metal-carbonate-zeolite
To provide an orchid-resistant composition in the form of a sintered body, which is made by sintering a composite substantially consisting of a binder and has excellent mechanical strength, water resistance, heat resistance, and ability to retain antibacterial activity, and a method for producing the same. be.

Other objects and advantages of the invention will be highlighted below.

The present invention relates to an antimicrobial composition consisting essentially of an antimicrobial metal-carbonate-zeolite and a method for producing the same.

The term 6 "antibacterial metal" used in the present invention broadly refers to a metal used as a bactericidal agent, but if we were to limit it, it would be one selected from the group consisting of zinc, copper, and silver, or a metal selected from the group consisting of zinc, copper, and silver. Defined as a mixed metal.

The antibacterial composition of the present invention is essentially composed of six components: carbonates, zeolites, and antibacterial metals, but in actual use, a binder is added as a subcomponent to strengthen the binding force between particles. It is added and molded into a fired body. The fired body formed into a desired shape by firing the composition of the present invention is used in contact with a liquid for the purpose of sterilization.
Excellent water resistance and strength of the fired product are required.

The carbonate used as one of the main components of the antibacterial composition of the present invention is preferably insoluble or sparingly soluble in water. Especially carbonates of alkaline earth metals (magnesium,
Carbonates of lucium, strontium, and barium) are sparingly soluble in water, and their thermal decomposition temperatures are high, so it is possible to calcinate the antibacterial composition at a considerably high temperature in the final calcination. There is an advantage that a fired body with excellent hardness can be obtained.

As the carbonate used as a component of the antibacterial composition of the present invention, one or more of the above-mentioned alkaline earth metal carbonates may be used. Further, there is of course no problem even if some basic salt etc. are mixed into the carbonate material.

Calcium carbonate is an example of an alkaline earth metal carbonate suitable for use in the present invention. It is sparingly soluble in water, and its solubility in water is about 15-20p+n at room temperature, and its thermal decomposition temperature is high, around 825°C, so it can be used as the carbonate component of the present invention with good results. . In the present invention, one or more of the above-mentioned alkaline earth metal carbonates are used in the form of particles or powder, which can be obtained by adding the carbonates, performing wet molding, drying, and baking. This has the effect of maintaining the strength of the antibacterial composition of the present invention at an extremely high level.

Alkali metal carbonates (lithium, sodium, potassium, etc.) are soluble in water, and when used as a component of the carbonate constituting the antibacterial composition of the present invention, the composition of the present invention is used to dissolve the alkali metal carbonate. When carrying out sterilization, a considerable amount of carbonate may be eluted into the liquid, which is undesirable.

As is well known, the zeolite used as a component of the antibacterial composition of the present invention is an aluminosilicate having a three-dimensional skeleton structure and has the general formula %. However, M represents a metal capable of ion exchange, and is usually a monovalent to divalent metal.

n represents the valence of the metal, X and y represent the coefficients of metal oxide and silica, respectively, and Z represents crystal water. The zeolite used as a component of the antibacterial composition of the present invention may be either a synthetic product or a natural product, but a thermally stable zeolite is more preferred.

Examples of synthetic zeolites include 8-type zeolide,
Preferred examples include type zeolide, Y-type zeolide, and mordenite. It is also possible to use synthetic zeolites such as ZSM.

On the other hand, as a natural zeolide, clinoptilolite (C1
1 noptilolite), mordenite (Mor
den ite), Chabazi
te), C ryonite, Ph1llipsite, Analcime, Faujasite (F
Zeolites such as zeolites are suitable for use in the present invention. These natural and synthetic zeolites are porous and have well-developed pores, and therefore have a large specific surface area, and are usually used in particle to powder form as one of the components of the antibacterial composition of the present invention. .

Next, the composition of the antibacterial composition of the present invention will be described.

As mentioned above, the antibacterial composition of the present invention mainly contains carbonates.
Zeolide - Composed of an antibacterial metal, but for practical use organic and/or inorganic binders are added to increase firing strength and formed into the desired shape by wet molding. .

It goes without saying that the antibacterial composition of the present invention may contain inorganic adsorbent substances such as silica gel and alumina as subcomponents in addition to the above-mentioned main components.

The actual usage form of the antibacterial composition of the present invention is as described above, in which a binder is added to a composition consisting of one or more carbonates of alkaline earth metals, a natural or synthetic zeolite, and an antibacterial metal. It is mainly composed of a fired body made by blending and firing.

Here, taking as examples of typical antibacterial metals, zinc, and copper, their content in the fired body and the weight ratio of carbonate to zeolite will be described.

When the antibacterial metal is silver, the silver content in the fired body is o, oo
It is preferably within the range of i to 20%, and the weight ratio C/Z of carbonate (C) to zeolite l-(Z) is preferably within the range of 0606 to 4. Bacteria, such as Streptococcus aureus, g1
Tanokuki V Escherichia coli, Pseudomonas aeruginosa
), and fungi, such as mold (Asper
In order for the anti-(E) composition of the present invention to have a sufficient cocooning effect against P. gillus flavus), the silver content in the composition of the present invention should be 0.001 as described above.
It is desirable that it be in the range of ~20%, with the most preferred range being 0.005-15%.

When the antibacterial metal is zinc, the zinc content in the fired body is at least 0.04%, and the weight ratio of carbonate (C) to zeolite (z) is e/
It is preferable that Z is within the range of 0.06 to O. On the other hand, when only copper is used as the antibacterial metal, the copper content in the fired body is small (both 0.06% or more and the above C
/Z is preferably within the range of 0.06 to 3. Next, the reason for limiting the numerical values as described above will be explained.

In the present invention, the blending ratio of calcium carbonate, natural zeolite or synthetic zeolite, and binder is varied, and
Various antibacterial compositions were trial-produced with different silver, zinc, or copper contents, and their anti-microbial properties and fungal killing rates were measured. When evaluating antibacterial properties, S taphylococcus aureusl Es
cherichia Co11 r Pscudomo
Evaluation was carried out by the disk method using bacteria such as S. nasaeruginosa. On the other hand, Aspergillus flavus was used to measure the mortality rate against Mankan. When the calcined body of the present invention, which was a composite of the zinc-human type 2 calcium carbonate binder, contained 16.2% zinc, the mortality rate against Aspergillus flavus was 100%. In addition, the fired body is a composite of zinc-Y-type zeolide and calcium carbonate binder.
%, the mortality rate against Aspergillus flavus was 98%, while 5 taphyloco
ccus aureus and Escherichia C
It was found that it also showed good antibacterial activity against bacteria such as O11. Zinc is 1.8% and 0.1% in the former fired body.
When zinc content is 1%, the mortality rate against Aspergillus flavus is 82% and 67%, respectively, and when the zinc content is 0.04%, the mortality rate against the above fungi is 26%.
It declined to . When the zinc content is 0.04% or less, the antibacterial activity further decreases, and when the zinc content is around 0[12% to 0.06%], the mortality rate was 10% or less in all tests.

For the above reasons, the amount of zinc in the fired body of the present invention was limited to 0.04% (anhydrous basis) or less. The same tests as for the above-mentioned zinc-containing fired body were conducted for the copper-containing main fired body, and a copper content of 0.06% (anhydrous standard) was set as the lower limit showing a preferable antibacterial effect. The reason for this is based on the following.

In the fired body of the present invention with a copper content of 5% or more, the mortality rate against Asperg usflavus K was 95 to 100% in both tests using two types of zeolite materials, natural and synthetic. Ta. -Blade steel content is 2~
With the 2.5% calcined body, the killing rate against the above bacteria was 70-88% in both tests using two types of zeolite, natural and synthetic zeolites. At around 1%, the mortality rate was 60-67%. - In the fired body of the present invention with a blade steel content of 1%, Escherichia colL Pseud
The antibacterial effect was still confirmed for B. omonasaerginosa bacteria. In a fired body with a copper content of 0.06% or less, the above-mentioned effect against bacteria decreases significantly as the copper content decreases. Therefore, in the fired body of the present invention containing only copper as an antibacterial metal, 0806% (anhydrous standard) was set as the lower limit of the amount. A similar test was conducted on silver-containing main fired bodies, and it was found that in compositions where the copper content was below the above-mentioned lower limit o, ooi%, the antibacterial effect decreased significantly as the copper content decreased; It was discovered that even when silver was used, the bactericidal effect remained almost constant regardless of the silver content, so the ranges for each metal were set as described above.

Next, the quantitative relationship between carbonate and zeolite in the composition of the present invention will be described. The range of C/Z=0.03 to 4 is preferable. When C/Z is 0.03 or less, the mechanical strength of the molded article of the antibacterial composition of the present invention has a drawback that it decreases significantly as the calcium carbonate content decreases. Generally, the strength of the compositions of the present invention increases in proportion to the amount of binder used and the content of calcium carbonate. On the other hand, in the range where C/Z is 4 or more, there is a drawback that as the amount of calcium carbonate added increases, it becomes gradually impossible to perform wet molding satisfactorily.

In the region of C/Z≦4, the silver and zinc of the present invention are very excellent in terms of mechanical strength and water resistance, and are satisfactory in terms of antibacterial effect and retention ability, as can be seen from the examples described below. It is possible to produce antimicrobial compositions containing single or mixed metals such as , copper.

Next, the characteristics of the method for molding the antibacterial composition of the present invention will be described. The antibacterial composition of the present invention is molded by a wet molding method. That is, it can be obtained by wet mixing a carbonate-antibacterial metal-zeolide complex in the presence of water or an aqueous urea solution using only an inorganic binder or a combination of an organic-inorganic binder. The mixture is molded into an appropriate shape using a molding machine, and then dried at a temperature below the onset of thermal decomposition of the carbonate component to be used, and below the onset of thermal decomposition of the zeolite component to be used. It is ready for actual use by firing.

Since the carbonates and zeolites used as components of the antibacterial composition of the present invention have already been described in detail, they are omitted here.

The antibacterial metal used in the present invention is stabilized by adding it in the form of water-soluble salts such as nitrates and sulfates, or by pre-holding a single antibacterial metal or a mixture of the two in the funite. It is added in the same state. In particular, according to the latter method, it is possible to prepare an active antibacterial composition in which the antibacterial metal is stably retained in the zeolite framework and the antibacterial effect is maintained over a long period of time. In the latter case, an aqueous solution of a water-soluble zinc salt, copper salt, silver salt, or a mixed salt of the above, such as silver nitrate, copper nitrate, zinc nitrate, or a mixed salt of the above, and powder to particulate natural or synthetic zeolite are mixed at room temperature. If ion exchange is performed in an acidic range with a pH of 7 or less at a high temperature (e.g. 60" to 90°C), part or most of the ion exchange groups in the zeolite skeleton will be converted to silver, zinc, copper, or the above mixed metal type. It is also possible to introduce silver, zinc or copper into synthetic zeolites of the A, By adjusting the concentration and reaction time of the salt solution brought into contact, it is possible to arbitrarily change the amount of silver copper and zinc retained in the zeolite phase.By carrying out such ion exchange, the retention of antibacterial metals becomes extremely uniform. The above-mentioned ion exchange method is preferable as a method for retaining antibacterial metals because it is carried out throughout the entire porous zeolite.Furthermore, the antibacterial metals in the same phase of zeolites, which have a large internal specific surface area, are very suitable for the zeolite matrix. When the antibacterial composition in such a state comes into contact with water, it not only has a large antibacterial effect, but also causes the elution of antibacterial metal ions into the aqueous solution phase. It has the advantage that compared to known bactericides, the concentration of silver, copper and zinc is all below the regulatory values.

As mentioned above, the antibacterial composition of the present invention comprising carbonate, antibacterial metal, and zeolide is wet-molded together with an inorganic binder or an organic-inorganic binder to form beads, tablets, pellets, or cylinders. It is formed into a shape, plate shape, honeycomb shape, or other suitable shape.

During wet mixing, the appropriate moisture content is 18 to 45%.
By maintaining the moisture content within this range and mixing for 3 to 5 hours, a blend that is easy to mold can be obtained. However, the water required for incorporation can be provided simply by adding water to the above composition or by adding an aqueous urea solution. By adding an aqueous urea solution, urea decomposes into gases such as NH3, CO, and H,0 during calcination of the antibacterial composition, and at this time, the antibacterial composition becomes more porous due to the foaming phenomenon caused by the above gases. There are some advantages.

Next, the binder used in molding the antibacterial composition of the present invention will be described. Preferred examples of the inorganic binder include bentonite, diatomaceous earth, kaolin, colloidal silica, and colloidal alumina. On the other hand, organic binders include cellulose (crystalline cellulose compounds such as methylcellulose, carboxymethylcellulose, and hydroxyethylcellulose), molasses,
Preferred examples include alginates and the like.

These inorganic and organic binders may be used alone or in combination, but when molding the antibacterial composition of the present invention, in particular, inorganic binders alone or in combination and organic-inorganic bonds may be used. It is preferable to use a combination of agents. Now, the amount of the above-mentioned binder used is controlled by the physical properties of the carbonate and zeolite that are the constituent components of the antibacterial composition, as well as the ratio of these amounts used, but in normal cases, it is based on the total amount of the above materials. A suitable range is 7-68%. When an organic binder and an inorganic binder are used together, the content of both is in the above-mentioned range of 7 to 68%, and the appropriate amount of the former is 2 to 6%. Carbonate is then molded into a predetermined shape through a mixing process.
The fired body made of zeolide-antibacterial metal-binder is 10
After drying at around 0° C., it is adjusted to exhibit a constant shape distribution. The dried molded body that has undergone this adjustment step is fired in a temperature range below the onset of thermal decomposition of the carbonate and zeolite used as components to finally obtain a fired body that can be used in actual use. The firing temperature range in this case is related to the types of ingredients used, but in normal cases, 650° to 650°C is appropriate, and 400°
~600"C is an extremely preferable temperature range. The antibacterial composition of the present invention prepared by the above-mentioned method is structurally extremely stable, and X-ray diffraction shows that the presence of antibacterial metal oxides is not detected. Almost no antibacterial metals are observed, and most of the antibacterial metals in the complex are bound to the zeolite and stably retained.

Since such an antibacterial composition is in an activated state, it is characterized by high antibacterial activity. Furthermore, the antibacterial composition of the present invention obtained by the above-mentioned method clearly has significantly higher mechanical strength and density than the Examples described below, and also has superior advantages in terms of antibacterial retention ability. Furthermore, it has been confirmed that when such a fired body comes into contact with a liquid, the antibacterial metal in the antibacterial composition is easily ionized, so that sterilization can be carried out under favorable conditions. 'Also, during antibacterial tests, it was confirmed that the elution of antibacterial metals into the liquid phase was extremely small.

Next, embodiments of the present invention will be described with reference to Examples, but the present invention is not limited to these Examples unless the gist thereof is exceeded.

Example 1 This example relates to the preparation of silver zeolite, which is a component of the antibacterial composition of the present invention.

Approximately 2 pieces of 8-type zeolide fine powder (commercially available NaZ-type) with a specific surface area of 549 m''/!i' and an average particle size of 6 μm was collected, and to this was added 0.1M silver nitrate aqueous solution of about 4/2 and water. The total volume was maintained at Zlj.The slurry mixture in this state was kept at room temperature under stirring for 7 hours.A part of the sodium in the ion exchange group of the zeolite was converted to silver by the above ion exchange reaction. Then, the NaAgZ solid obtained by filtration was washed with water until excess silver ions were removed.
The NaAgZ was dried at 100"-110°C. This conversion test yielded a dry powder of about 2008".
9 was obtained. In this case, the iron content in the dry N a A g Z powder was 2.07%.

Example 2 This example relates to a method for preparing the antibacterial composition of the present invention. Silver-zeolide (N
aAgZ-Dry Powder) 150-200 for 35['
650 g of finely powdered calcium carbonate from Metsuyu was added.

100-2 as an inorganic binder for the above mixture.
00 mesh bentonite fine powder 60% (210
When 1 was added, mixing using a mixer was carried out for about 4 hours. Next, 26% water was added to the mixture and wet mixing was carried out for about 30%.
It was carried out over a period of time. The mixture obtained by this process was molded using a twin-shaft molding machine to obtain 1/16" pellets. Subsequently, the pellets were dried at 100° to 11".
After drying at 0℃, the length was adjusted using a flasher1, and the dried pellet was heated at 560℃ to 5℃.
A 1716' fired body of the antibacterial composition of the present invention was baked at 50°C for 6 hours and 60 minutes (Ag content = 0.89% (anhydrous basis))
] was obtained.

Table 1 shows the hardness of the antibacterial composition obtained in this example. In addition, the average value of the apparent density of this product reached 1,639.

Table 1 Hardness of the antibacterial composition obtained in Example 2 (calcined 1/16' (0.15 cm) The values shown below are based on a sample test of the antibacterial composition obtained in this example. The results show that the average hardness of 1/16" pellets (calcined) C = 12.3V pellets. It is clear that the antibacterial properties of the present invention are evident from the average value of apparent density and hardness. The composition has extremely high hardness and therefore great durability, indicating that it is suitable for sterilization purposes (see Example 5).

Example 3 This example describes an example in which the antibacterial composition of the present invention was prepared using a natural zeolite material.

Natural mordenite zeolite powder (100-200 mesh) with specific surface area 348m'/g 2.5kli
+ was ion-exchanged using a silver nitrate solution at room temperature in the same manner as described in Example 1, and some of the metals in the exchange groups of mordenite were converted to silver, resulting in silver-substituted natural Obtained mordenite.

Next, 2.5 kg of the above-mentioned dry powder of silver-type mordenite was collected, and 28.6% (650.1%) of powdered calcium carbonate of 150 to 200 meshes was added to it. 100-2 as a binder in the system
00 metsunyu fine bentonite powder 1a15 (44
8g) and methylcellulose (Me
thyl cellulose) [Commercial product from Tokyo Kasei Kogyo Co., Ltd.: 7.000-10.0OOcps (2
22% viscosity of an aqueous solution (at 0° C.)] was added and mixed using a mixer for 2 hours.

Next, a 6% aqueous urea solution was added to the mixed powder, and wet mixing was carried out for 6 hours and 10 minutes. In this case, the moisture content at the end of mixing was 27 qb. The mixture obtained in the above process was molded using a twin-screw molding machine to obtain 1/16" pellets. Subsequently, the pellets were dried at 100° to 110°C and their length was adjusted. was carried out using 7 lashers.

Finally 1/16" dry pellets at 550°-560℃
1/16 which is the antibacterial composition of the present invention by baking for 3 hours.
An N fired body with a CAg content of -1.52% (anhydrous basis) was obtained.

Table 2 Hardness of the antibacterial composition obtained in Example 6 (calcined 1/16'' pellets) The hardness of the antibacterial composition obtained in this example is listed in Table 2. The values indicate the results of sampling tests. 1/16'
The average hardness of the fired pellets reached 13.41 V/Bellet. From this, it is clear that the antibacterial composition of the present invention has excellent hardness.

Example 4 This example relates to the evaluation of the antibacterial activity of the antibacterial composition of the present invention obtained in Example 2 and the fungal killing rate for the antibacterial compositions obtained in Examples 2 and 6. be.

When evaluating the antibacterial activity, the test substance was precipitated to a concentration of 100 y/d and soaked into the disk. As the culture medium, Muel Ier Hinton medium was used for bacteria, and Sabouraud agar medium was used for fungi. The test bacteria were dispersed using a 0.1 ml Conlage rod in a medium suspended in 10 II/7 saline. The disk to be tested was attached onto it.

For determination, the sample was maintained at 67° C. for 18 hours and the presence or absence of inhibition zone formation was observed. On the other hand, fungi were evaluated after being kept at 60°C for 7 days.

The fungal mortality rate was measured by the following method.

Aspergillus flavus spore suspension (
111 tl of 10'/m4') was added to the prefectural slurry of the test substance (5
00my/m), injected and mixed into 9mJ for 24 hours3
It was operated at 0'C.

Disperse 0.1 of this on Sabouraud agar medium and hold at 30°C.
After holding for 48 hours, the number of surviving cells was measured and the mortality rate was calculated.

Table 3 Antibacterial evaluation of antibacterial compositions obtained in Example-2 and B :Ag=0.89%
(anhydrous standard)] was used as a fine powder to evaluate its antibacterial properties. As shown, it was found that good results were obtained for all four types of bacteria. As a comparative example, the zeolite material of Example-1 (
The results of the antibacterial evaluation of the Na-type dry powder of A-type zeolide are listed in Table 3, but the antibacterial effect is not seen at all with the zeolite material alone.

Table 4 also shows the antibacterial composition of the present invention obtained in Example-2 [1/1 (S" pellet (calcined); Ag=0.
89% (anhydrous standard)] and its powder and Example-6
Antibacterial composition [1/16'' pellets [calcined]: Ag
= 1.52% (anhydrous standard)] was measured using Aspergillus flavus as the fungus. As is clear from the table, there is no doubt that the antibacterial composition of the present invention exhibits extremely high antibacterial effects against fungi. On the other hand, as noted in the comparative example in the same table (synthetic or natural zeolite materials alone have no effect on fungi. The method is similar.

In addition, the mortality rate of the molded body described above was measured using Aspergill.
An antibacterial molded body was immersed in a spore suspension of S. usfluvus (104 spores/-), and the killing rate was measured according to the method described above.

Table 4 Measurement of fungal killing rate using the antibacterial composition of the present invention a) Antibacterial composition 1 of the present invention obtained in Example-2
/16" pellet fine powder sample b) Zeolite material used in Example-1 Two-person type zeolite (Na-type powder dry sample) C) Natural mordenite zeolite used in Example-3): 100-200 mesh Dry Sample Example-5 This example relates to testing the water resistance and ability to retain antibacterial activity of the antibacterial composition of the present invention.

Approximately 15.9 pieces of the antibacterial composition of the present invention (calcined 1/16" pellets) obtained in Example 2 were collected in a small glass column with an inner diameter of 22 m, and washed back with water. To this, city tap water (Ca” = 1
7P; Mg2″-=6.8ppm; CI=34p
) at a flow rate of 33±1.5 ml/min to conduct a test regarding the water resistance and antibacterial ability of the composition of the present invention. Table 5 shows the relationship between the amount of water passing through and the silver concentration in the effluent from the small column. During the test, when the liquid volume reached the indicated value, a small amount of the liquid flowing out from the bottom of the column was sampled, and the concentration of silver in the liquid was determined by atomic absorption spectrometry. As can be seen from Table 5, the elution of silver from the antibacterial composition of the present invention was extremely small, in ppb-amount, and a satisfactory result was obtained. It should be noted that no damage to the shape of the molded product of the open-ended composition was observed in the water flow test, and it was therefore found that the molded product had excellent water resistance. Next, the above-mentioned total effluent volume is shown in Table 5 Water flow test of the composition of the present invention 10.0 5 30.0 4 80.0 5 101.0 7 153.0 6 201.0 8 Water flow test of 2011 In order to confirm the durability of the antibacterial activity of the used antibacterial composition, the fungal kill rate was measured using Aspergillus flavus.
It was carried out using Since the method for this measurement is the same as that for measuring the fungal mortality rate shown in Example 4, only the results are shown in Example 6.
Shown in the table. It is clear from this table that the antibacterial effect of the composition of the present invention is large and that the antibacterial properties are maintained for a long time.

Table 6: Compositions of the present invention that had been subjected to a water flow test were used.

Test substance Mortality rate (%) (Water flow test completed product, 1/16" pellet) Example-6 This example is a method in which copper is pre-preserved in the zeolite used as a component of the antibacterial composition of the present invention. This paper relates to a method for preparing copper-A-!zeolite (NaCuZ).Dry powder of 8-type zeolide (specific surface area 676
I; Chemical composition, 1.01NatO-AltOs-
i, 96 sio 2- In this case, the pa of the mixed solution was adjusted to 4.6 using a dilute acid or dilute alkaline solution. The mixture was stirred at room temperature for 8 hours.

After the completion of the above ion exchange reaction, centrifugation was performed to separate the solid phase. Next, the zeolite solid phase was washed with water until no sulfate ions were observed, and then the obtained NaCuZ was dried at 100° to 105°C.

In this example, 1.55 kg of NaCuZ dry powder was obtained.

Example-6 Preparation form of NaCuZ Amount: 1.55 kg (dry powder) Solid phase metal component of NaCuZ: c? =0.2237;
+' = 0.7763 (equivalent fraction) Example 7 This example is a copper-Am type zeolite (NaC' It concerns the preparation of uZ:). Same A-type zeolide powder 1.6 as used in Example-6
To kfl, 5.61 parts of 0.6M cupric sulfate solution and water were added to maintain the total volume at approximately 5.91 parts. In this case, the pH of the mixture was adjusted to 4.5.

After the mixture was heated and maintained at about 65° C., it was continuously stirred at the same temperature for 4 hours.

After the above ion exchange reaction was completed, centrifugation was performed to separate the solid phase.

Next, the zeolite solid phase was washed with water until no sulfate ions were observed, and the obtained NaCuZ was
It was dried at 105°C. In this example, 1.57 kg of NaCuZ dry powder was obtained.

Example-7 Preparation of NaCuZ Amount: 1.57 kli + (dry powder) Solid phase metal component of NaCuZ: Cu" = 0.3779; Na = 0
．． 6221 (equivalent fraction) Example 8 This example shows zinc-A-, which is prepared by holding zinc in zeolite used as a component of the antibacterial composition of the present invention.
The present invention relates to the preparation of type zeolide (NaZnZ). Dry powder of 8-type zeolide (specific surface ft692d/
, 9; Chemical composition, 1.02NatO.Al2O3.1.
94Si02・XH,O) 0.8M for approximately 1.3 h
Add 6.6 g of subsalt chloride solution and water to bring the total volume to about 4 g.
It was held at 61. In this case, the pH of the mixture was adjusted to 4.2. After raising the temperature of the mixed solution and keeping it at 50°C, continuous stirring was performed at the same temperature for 6 hours.

After the above-mentioned ion exchange was completed, centrifugation was performed to separate the solid phase. Next, the zeolite in phase was washed with water until chloride ions were observed <1x, and the resulting NaZnZ
was dried at 100° to 105°C. In this example, NaZ
1.22 kg of dry powder of nZ was obtained.

Example-8 Preparation of NaZnZ Yield: 1.22 hours (dry powder) Solid phase metal component of NaZnZ: Zn''=0.5914; Na+=0.4086 (current fraction) Example-9 Present implementation An example is given of a method for the preparation of a zinc-criptylolite type in which natural zeolite is preloaded with zinc for use as a component of the antibacterial composition of the present invention.Natural clinoptilolite (from North America) 1.2 parts of 1M zinc chloride solution was added to approximately 60011 of the fine powder.The pH of the resulting mixture was adjusted to 4.1.The mixture containing the zeolite was stirred at room temperature for 6 hours. After the completion of the above ion exchange reaction, centrifugation was performed to separate the solid phase, which was washed with water until no chloride ions were observed, and then dried at 100° to 105°C.In this example, zinc- A dry Klip Tyrolite powder 580Ii was obtained.

Example-9 Preparation of zinc clinoptilolite Yield: 58
0. ! i' (dry powder) Zinc content: Zn = 1.74% (anhydrous basis) Next, the antibacterial composition of the present invention was molded under the conditions illustrated in Table 7.

In Examples 10 and 11, NaCuZ and calcium carbonate powder were molded using bentonite and a combination of bentonite and methyl cellulose binder, respectively. In the latter case, methyl cellulose (20 Viscosity of 2% aqueous solution at °C =
7. In Example-12, only bentonite binder was added to the mixed powder of NaZnZ and calcium carbonate and wet molding was carried out, and in Example-16, zinc- For a mixture obtained by adding calcium carbonate powder to clinoptilolite (natural zeolite), in the same manner as in Example 12,
Molding was performed by adding only a bentonite binder. The moisture required in the wet mixing described above was achieved by simply adding water as indicated, or by adding a 6% urea aqueous solution, and the moisture content was maintained as indicated.Next, the molded pellets were dried by collapsing. Even in the example of 100° to 105
°C, while the calcination of the dry pellets was carried out in Example 10.
In Example-12, the test was carried out in a temperature range of 510° to 520°C for 4.5 hours, and in Example-16, the test was carried out in a temperature range of 560° to 540°C for 4 hours.

Table 8 shows the physical property values of the antibacterial fired pellets obtained by this molding, and the average strength of the pellets in the table is high, and the apparent density is also high (. .

The effect of using a carbonate such as calcium carbonate in wet molding an antibacterial composition containing zinc or copper is clear from the physical property values listed.

Table 8: Physical properties of molded bodies of antibacterial composition Next, antibacterial tests of the antibacterial composition of the present invention were carried out on both molded bodies and crushed products thereof.

The antibacterial activity of the pulverized molded product was evaluated by the following method. 100+p/ml of pulverized test substance
It was soaked into a prefecture turbid disk to a concentration of . Mueller Hinton medium was used for bacteria, and Sabouraud agar medium was used for fungi. The test bacteria were suspended in physiological saline at a rate of 10 8 cells/p, and dispersed in the medium using a Q, 1 ml Conlage rod. The disk to be tested was attached onto it.

For judgment, the presence or absence of an inhibition zone was observed for bacteria after 18 hours had passed at 67°C. Fungi were determined after one week at 30°C.

On the other hand, the fungal mortality rate was measured by the following method.

1 ml of Aspergi Ius f Iavus spore suspension (104 spores/d) was added to the test substance suspension (50
The mixture was injected and mixed into 9M (0 da/mJ) and allowed to act at 60°C for 24 hours. The o, i mJ was dispersed on a Sabouraud agar medium, and after 48 hours at 68°C, the number of surviving individuals was measured to determine the mortality rate.

Next, the antibacterial activity of the molded body was evaluated using the molded body as a test disk according to the above-mentioned evaluation method, and the fungal kill rate of the molded body was measured using Aspergi l1usf 1av.
The antibacterial molded body was immersed in a suspension of spores (10 4 spores/ml) of U.S. spores, and the killing rate was measured according to the method described above.

The results of the antibacterial test are shown in Tables 9 and 10. The fungus (Aspergillus flavu) of the antibacterial composition of the present invention
The mortality rate against s) is as shown in Table 9, and the bactericidal activity is excellent. Furthermore, Table 10 shows the results of antibacterial evaluation regarding four types of bacteria. Comparative example shown in the diagram - Humans were tested using basic copper carbonate fine powder (CuCO3+) as a test subject.
Cu (0H)z ・Ht O (approximate composition); Cu = 5
5.2%], but it was also found to have no effect in the antibacterial test of (i'J).

Although the copper content in the above powder reaches a high value of <53.2% as indicated, no antibacterial activity is observed. This is thought to be due to the fact that no release of copper ions was observed. - In the strength wood invention, antibacterial zinc or copper is stably bonded to zeolite, and in order to increase the strength and density of the stiff molded product, a carbonate such as calcium carbonate is combined with the coexistence of a binder. The molding, drying, and bottom of the mine are being carried out below. The antibacterial metal in the fired body is combined with the zeolite and does not form a compound with the carbonate.

For this reason, it is thought that zinc and copper ions are rapidly dissociated near the active sites of porous zeolite, and that it is possible to exhibit good antibacterial activity even in the presence of a small amount of antibacterial metal. This point is one of the characteristic advantages of the present invention.

Table 9 Measurement of fungal killing rate <Example-14> This example is a molded article (pellet) of the antibacterial composition of the present invention.
This is related to the water flow test. Antibacterial h6 pellet obtained in Example-16 (Cu = 2.98% (anhydrous standard); C = 5.12 kg/pellet; Apparent density = 1.2
Approximately 7 I of 56) was collected in a glass column with an inner diameter of 22 decoys. After backwashing with water, uniform filling of antibacterial pellets was carried out. Next, city tap water was passed downward at a flow rate of 15 to 20 ml/wit+, and the relationship between the amount of liquid effluent from the car ram and the copper concentration contained in the effluent was tested (11th
(see table). It was found that the elution of copper was carried out in small amounts under favorable conditions (regulatory value for copper when discharged into general rivers: 6 or less). Further, no breakage of the pellets was observed during the water flow, indicating that the pellets had sufficient water resistance. After completing the water flow test in 2001, the antibacterial ability against AspergNIus flavus was measured using a portion of the used pellets, and the killing rate was 41.8%, confirming that it was still effective.

Table 11 Water flow test (Example-10, '16./Using pellets) Next, a water flow test completely similar to the above was conducted using the antibacterial heat 6 pellets (Zr+-7, 28%
;C=6.96 to 9/beret;apparent density -1,359
) Approximately 7 g was used. The test conditions are exactly the same as the previous example, so they will be omitted. The results of the water flow test are shown in Table 12, and the zinc concentration in the effluent was maintained at 130 to 190 ppb (regulatory value for zinc when discharged into a general river: 5 or less). Further, during the water flow test, no breakage of the pellets was observed during the heat 6 test, and the water resistance of the pellets was also good. After completing the water flow test, Asperg using a part of the used pellet
The measured mortality rate for NIus flavus was 19
%Met.

Table 12 Water flow test (Example-7, heat 6〃be used)
The antibacterial composition of the present invention is expected to be sufficiently effective when used not only in a liquid phase but also in a gas phase for the purpose of sterilization.

Patent applicant Yoshitsugu Hagihara

Claims (1)

[Claims] 1. An antibacterial composition comprising a carbonate, a zeolite, and an antibacterial metal. 2. Antimicrobial composition consisting of carbonate, zeolite, antimicrobial metal and binder. 6 Wet blending the composite of carbonate, zeolite, antimicrobial metal and binder in the presence of water or aqueous urea solution, molding the resulting blend into the desired shape, subsequent drying and final mixing. 1. A method for producing an antibacterial composition in the form of a fired body, which comprises firing at a temperature range other than the start of thermal decomposition of carbonate and below the start of thermal decomposition of zeolite. 4. A composition according to claims 1 to 2, wherein the antimicrobial metal is selected from the group consisting of silver, zinc, copper and a mixture thereof. 5. The method of claim 6, wherein the antimicrobial metal is selected from the group consisting of silver, zinc, copper and mixtures thereof. 6. The method according to claim 6, wherein the antibacterial metal is silver. 7. The method according to claim 6, wherein the copper content in the fired body is from o, ooi to 20%. 8. The method according to claim 6, wherein the antibacterial metal is zinc. 9. The method according to claim 8, in which the zinc content is 0.04% in the center of the fired body. 10. The method according to claim 6, in which the antibacterial metal is copper. 11. 11. The method according to claim 10, wherein the center of the fired body is at least 0.06% °C.