Bactericide, coating material, product, production method, and production device

Abstract

The present invention provides a bactericide having appropriate bactericidal ability according to the application, by adsorbing a sufficient amount of silver ions onto a photocatalyst and adjusting the amount of silver ions to be adsorbed. A bactericide according to one embodiment of the present invention contains titanium dioxide on which silver ions are adsorbed, and is characterized in that the silver ions having a concentration that can be selectively adopted in a concentration range of 1 to 250 ppm are adsorbed on the titanium dioxide, and that a redissolution concentration of the silver ions is 5 ppb or less.

Description

Disinfectants, paints, products, manufacturing methods, and manufacturing equipment

[0001] The present invention relates to disinfectants, coatings, products, manufacturing methods, and manufacturing equipment.

[0002] Countermeasures against infectious diseases are a global issue, but current countermeasures such as masks and alcohol disinfectants are limited. For example, blocking the spread of bacteria through contact and reducing the risk of infections caused by drug-resistant bacteria would greatly contribute to countermeasures against infectious diseases. Conventionally, antibacterial agents in solid or liquid form have been known, and among these, photocatalysis-related technology that utilizes the redox power of photocatalysts is known as a solid antibacterial agent. Some of this photocatalysis-related technology can be used to block the spread of bacteria through contact.

[0003] Patent Document 1 listed below describes a photocatalytic apatite composition in which silver ions are doped into a photocatalytic apatite composition.

[0004] Furthermore, Patent Document 2 listed below describes a disinfectant that contains titanium dioxide that has adsorbed silver ions, and also contains an aqueous resin binder to which a thermosetting crosslinking agent is applied, and in which the weight distribution of titanium dioxide particles of 100 nm or less is less than 0.3%.

[0005] JP 2007-260587 A Japanese Patent No. 7239122 A

[0006] Patent Document 1 discloses that doping a photocatalytic apatite composition with silver ions makes it possible to exhibit antibacterial properties in the dark; however, it is difficult to increase the amount of silver ions to be doped, and the silver ions doped into the photocatalytic apatite composition dissolve in the liquid, making it impossible to sustain antibacterial properties in the dark.

[0007] The material in Patent Document 2 contains titanium dioxide with adsorbed silver ions, and thus has antibacterial properties in the dark, similar to Patent Document 1, and is biocompatible because it uses an aqueous resin binder with a thermosetting crosslinking agent, and the weight distribution of particles of 100 nm or less is less than 0.3%, so it is not environmentally toxic due to nanoparticles. However, it is difficult to increase the amount of silver ions adsorbed to titanium dioxide.

[0008] The present invention aims to provide a bactericide having a bactericidal ability appropriate for the intended use by adsorbing a sufficient amount of silver ions onto a photocatalyst and adjusting the amount of adsorbed silver ions.

[0009] A first aspect of the present invention is a disinfectant containing titanium dioxide having silver ions adsorbed thereon, characterized in that the titanium dioxide has adsorbed thereon silver ions at a concentration that can be selectively adopted within the range of 1 to 250 ppm, and the re-elution concentration of the silver ions is 5 ppb or less. With this disinfectant, a sufficient amount of silver ions is adsorbed onto the photocatalyst, and by adjusting the amount of adsorbed silver ions, a disinfectant with appropriate disinfecting ability depending on the application can be provided.

[0010] One embodiment of the disinfectant of the present invention is a disinfectant with high-performance disinfecting properties, containing titanium dioxide with a high density of adsorbed silver ions. Titanium dioxide is white and has high light-shielding properties, and is therefore used in a wide range of applications as a pigment. The catalytic activity of titanium dioxide is adjusted by factors such as the firing conditions during production. Among these, titanium dioxide used as a pigment is used in paints, cosmetics, etc., and therefore has low photocatalytic activity to avoid decomposition of surrounding organic matter. In addition, some of these pigments have their surfaces coated with inorganic materials to further suppress the photocatalytic activity of titanium dioxide.

[0011] The titanium dioxide particles used in the present invention have lower photocatalytic activity than those used as photocatalysts for sterilization, such as titanium dioxide used as a pigment. By using titanium dioxide particles with low photocatalytic activity, a sterilization effect due to photocatalytic activity can be achieved in the presence of light. However, the catalytic activity of the titanium dioxide particles used in the present invention is limited to a specific range, so there are no adverse effects such as deterioration of textile materials. Moreover, commercially available titanium dioxide particles for pigments have lower photocatalytic activity than titanium dioxide for sterilization, but are inexpensive and economical. By using titanium dioxide with a particle size of 100 nm to 1 μm and a weight distribution of particles of 100 nm or less of less than 0.3%, a sterilization agent that does not exhibit environmental toxicity due to nanoparticles can be obtained. The particle size of the titanium dioxide is normally distributed between 100 nm to 1 μm, but the weight distribution of particles of 100 nm or less is less than 0.3%, i.e., the sterilization agent of this embodiment is substantially free of nanoparticles. Therefore, there are no problems with biocompatibility, particularly cytotoxicity, due to nanoparticles, and there are also no problems with skin irritation and skin sensitization.

[0012] Recently, the U.S. EPA registered nanosilver as a material preservative, reflecting the current interest in the anti-infective properties of nanomaterials. The leaching rate of nanosilver from "NSPW-treated textiles" was below the detection limit, presuming that the possibility of environmental exposure of the polymer was negligible, leading to the EPA's registration. While the cytotoxicity of nanoparticles has been identified and efforts are underway to address this issue, the disinfectant of this embodiment, which has silver ions adsorbed onto titanium dioxide, does not use nanosilver, which has been a concern in the first place, making it highly safe. Furthermore, the re-elution concentration of silver ions is below 5 ppb, meaning that the titanium dioxide adsorbed onto the titanium dioxide is hardly re-eluted into the liquid. This ensures reliable bactericidal action upon contact with the target to be disinfected, while also avoiding environmental compatibility issues, making the disinfectant of this embodiment extremely safe. Thus, the EPA is regulating nanosilver from the perspective of environmental impact, citing the risk of nanosilver's continuous release of silver ions. On the other hand, the disinfectant of the present invention is safe in two senses, since it does not use nanosilver and silver ions are not re-eluted.

[0013] In the first aspect of the present invention, the term "disinfectant" is used. Conventionally, for example, alcohol disinfection has an immediate bactericidal effect, but it does not last. Therefore, conventionally, even if 80% of bacteria is killed by alcohol, there is a high risk that the remaining bacteria will grow again. On the other hand, the disinfectant of the first aspect of the present invention has a continuous bactericidal effect, so that even if the bactericidal effect is 90% after 12 hours, the 24-hour bactericidal effect of the JIS standard can be achieved at 99.99%. Furthermore, because the bactericidal effect is continuous, the number of bacteria continues to be reduced, and for example, after 30 hours, the number of bacteria will be reduced to 10%. －６The bactericidal effect of the bactericide of the first aspect of the present invention is sustained, and therefore it is an extremely useful bactericide that differs from the conventional definition of bactericidal effect. The bactericidal effect of the present invention is as sustained as copper, which is the only bactericide recognized by the U.S. EPA as a sustained-lasting bactericide. This means that the bactericidal effect continues as long as copper is present. The bactericidal effect of the bactericide of the present invention is also similar to that of copper, and the bactericidal effect continues as long as the bactericide remains present on the surface of the product. Because the bactericide of this aspect is a sustained-lasting bactericide, it achieves sterilization, thereby preventing the development of resistant bacteria.

[0014] Hereinafter, the agent of the present invention will be referred to as a "bactericide" from the viewpoint of its sustained bactericidal effect, but the agent of the present invention may also be referred to as an "antibacterial agent" from the viewpoint of inhibiting bacterial growth. Furthermore, the agent of the present invention may also be referred to as a "sterilant" from the viewpoint of being able to kill all bacteria. Naturally, the agent of the present invention also functions as a "disinfectant" and a "disinfectant." Therefore, the term "bactericide" of the present invention can be replaced with other terms such as "antibacterial agent," "sterilizer," "disinfectant," and "disinfectant," which mean that the agent of the present invention functions to inhibit the growth of other bacteria or reduce the number of bacteria.

[0015] The silver ions adsorbed to such titanium dioxide particles with low photocatalytic activity not only exhibit antibacterial effects, but also have antiviral, antiallergenic, bactericidal, antifungal, and anti-odor properties, regardless of the presence or absence of light. Moreover, the titanium dioxide particles used in the disinfectant of this embodiment have some photocatalytic activity, even if their photocatalytic activity is low. Therefore, in the presence of light, this, combined with the action of the silver ions adsorbed to the titanium dioxide particles, can effectively decompose dead bodies of viruses, bacteria, mold, etc., allergens, odorous substances, and even dirt. Therefore, the disinfectant of this embodiment has at least one of excellent antiviral, antiallergenic, bactericidal, antifungal, and anti-odor properties for a long period of time, regardless of the presence or absence of light.

[0016] The silver ions adsorbed on titanium dioxide used in one embodiment of the antibacterial fiber material of the present invention hardly dissolve in water. The amount of silver ions dissolved is on the order of a few ppb. In particular, when the silver ions are fixed to the fiber with a resin binder, the amount of silver ions eluted is within a few ppb (specifically, about 1 ppb) even after immersion in water for 10 days. Because the silver ions are firmly adsorbed and fixed to the titanium dioxide surface at a high concentration and do not re-leach, the disinfectant of this embodiment can exhibit both the disinfecting function of silver ions adsorbed on the surface in a solid state and the disinfecting function of titanium dioxide as a photocatalyst, thereby possessing high-performance disinfecting properties. As a result, the disinfectant mainly decomposes dead bodies of viruses, bacteria, mold, etc., as well as allergens, odorants, and dirt. Furthermore, because the silver ions hardly dissolve, the disinfectant of one embodiment of the present invention maintains at least one of antiviral, antiallergenic, disinfectant, antifungal, and anti-odor properties for a long period of time.

[0017] In the disinfectant of the first aspect of the present invention, silver ions are adsorbed onto titanium dioxide in a silver ion solution having a silver ion concentration of 1 to 250 ppm, and the concentration of this silver ion solution can be adjusted depending on the application. That is, with the disinfectant of this embodiment, the bactericidal activity can be freely adjusted depending on the application. For example, the bactericidal activity can be appropriately set depending on the application, such as using a silver ion solution with a concentration of 120 ppm for sterilizing medical instruments, a silver ion solution with a concentration of 80 ppm for antibacterial coating of treatment beds, or a silver ion solution with a concentration of 50 ppm for treatment of bedsores. Furthermore, because the bactericidal activity can be quantified based on the concentration of the silver ion solution used when adsorbing silver ions onto titanium dioxide, it is easy to display the bactericidal activity of the disinfectant of this embodiment, and it is also easy to prepare a disinfectant that exhibits the set bactericidal activity. The bactericidal activity of the disinfectant can be easily controlled during production, use, and inventory management.

[0018] Even a disinfectant with a silver ion concentration of 1 ppm adsorbed onto titanium dioxide exhibits a sustained bactericidal effect and therefore functions as a disinfectant. However, the lower limit of the silver ion concentration is set at 1 ppm, based on the viewpoint that a significant bactericidal effect is observed in the 24-hour bactericidal effect specified in the JIS standard when used as a disinfectant. Furthermore, a disinfectant with a higher concentration of silver ions, such as 250 ppm, specified as the upper limit in the first embodiment, adsorbed onto titanium dioxide exhibits a sustained high bactericidal effect and is therefore particularly usable for applications requiring a high bactericidal effect, such as medical applications requiring sterilization. In conventional technology, the upper limit for the concentration of silver ion solutions was approximately 30 ppm, and silver ion solutions above this concentration could not be used. However, the disinfectant of the first embodiment of the present invention has an upper limit of 250 ppm silver ion concentration, which was not possible in conventional technology. While conventional technology could not use silver ion solutions above 30 ppm, the apparatus for producing a silver ion solution of the present invention can increase the silver ion concentration to 120 ppm within 24 hours. From the viewpoint of an adjustment time of 24 hours or less, the upper limit of the silver ion concentration is 120 ppm, but from the viewpoint that the silver ion concentration can be increased to 250 ppm in the apparatus for producing a silver ion solution of the present invention within the range of an adjustment time allowable in a practical manufacturing process if the adjustment time is not limited to 24 hours, specifically, from the viewpoint of preparing a silver ion solution within 120 hours, the upper limit of the silver ion concentration was specified as 250 ppm. Of course, if the preparation time of silver ions is limited, it is theoretically possible to prepare a silver ion solution of even higher concentration.

[0019] The disinfectant of the first aspect of the present invention also has a sustained bactericidal effect, an effect not found in conventional technology. Conventional disinfectants, such as alcohol disinfectants, have excellent short-term bactericidal effects, but the bactericidal effect is not sustained, so even if the number of bacteria is reduced at one point, the bacteria will grow again. In contrast, in products using the disinfectant of this embodiment, the use of a disinfectant with an adjusted silver ion concentration exhibits bactericidal ability according to the application, and the bactericidal ability persists for a long period of time, for example, 30 days or more, thereby continuously suppressing bacterial growth. This significantly reduces the risk of developing resistant bacteria.

[0020] As described above, the second aspect of the present invention is characterized in that the concentration of silver ions adsorbed to the titanium dioxide in the first aspect of the disinfectant is selectively selected within the range of 30 to 150 ppm. In the disinfectant of the present invention, the concentration of silver ions adsorbed to titanium dioxide in the silver ion solution is 1 to 250 ppm, preferably approximately 30 to 150 ppm. While conventional technology has been unable to employ silver ion solutions with concentrations of 30 ppm or higher, the apparatus for producing a silver ion solution of the present invention can increase the silver ion concentration to 120 ppm within 24 hours. Furthermore, since the silver ion concentration can be increased to 150 ppm within a 30-hour preparation time, the silver ion concentration of the silver ion solution in the second aspect of the disinfectant is specified to be 30 to 150 ppm from the perspectives of the disinfectant manufacturing process and the disinfecting effect required for the disinfectant's intended use.

[0021] For example, when titanium dioxide powder is added to 120 ppm silver ion water, the silver ion concentration in the silver ion water drops to a few ppb. If the titanium dioxide is then removed from the silver ion water, dried, and then placed back into water, the silver ion concentration in the resulting water drops to a few ppb—in the example of the embodiment below, it is as low as 5 ppb or less, demonstrating that the silver ions are not re-eluted. Thus, it has been found that titanium dioxide adsorbs silver ions through its electronic function and retains them for a long period of time, preventing their re-elution in the liquid. While conventional disinfectants contain silver ions in a liquid state, the disinfectant of this embodiment adsorbs silver ions onto titanium dioxide, resulting in a solid disinfectant. By forming the disinfectant into a solid state, it is possible to continuously block the spread of bacteria through contact, thereby providing anti-infective properties.

[0022] The disinfectant of the third aspect of the present invention is characterized in that, in the disinfectant of the first aspect of the present invention, at least a portion of the silver ions are present in the form of at least one of silver oxide, silver hydroxide, and elemental silver, and in a state adsorbed to titanium dioxide. In a disinfectant in which silver ions are adsorbed to titanium dioxide in a silver ion solution, the silver ions are adsorbed throughout the manufacturing process and are not re-eluted. When titanium dioxide is dried in the silver ion solution using, for example, a spray dryer, at least a portion of the silver ions are present in the form of at least one of silver oxide, silver hydroxide, and elemental silver, and in a state adsorbed to titanium dioxide. Even when the disinfectant is in a dry state and at least a portion of the silver ions are present in the form of at least one of silver oxide, silver hydroxide, and elemental silver, and in a state adsorbed to titanium dioxide, they are converted into silver ions by a small amount of moisture, and therefore the silver ions contribute to the disinfecting effect when the disinfectant is used.

[0023] A fourth aspect of the present invention is characterized in that the disinfectant of the first aspect of the present invention is in the form of a dry powder, and a fifth aspect of the present invention is characterized in that it contains the disinfectant of the fourth aspect of the present invention. Furthermore, a sixth aspect of the present invention is characterized in that it uses the paint of the fifth aspect of the present invention. By utilizing the silver ion adsorption property of titanium dioxide, titanium dioxide adsorbed with silver ions can be used as a disinfectant, and this titanium dioxide can be made into a dry powder disinfectant using, for example, a spray dryer. This dry powder disinfectant is easy to handle and can be easily processed into various products in the subsequent process. By adding a binder or the like to this dry powder disinfectant, it can be made into a paint. Furthermore, this paint is applicable to a variety of products with various uses.

[0024] By making the disinfectant into a dry powder, it is possible to provide the disinfectant at low cost. For example, it can be easily processed into powder using a spray dryer, etc. The powder is easy to transport and handle. Variations of disinfectants with various ion concentrations can be manufactured, transported, and stocked. The stocked disinfectant in a dry powder state can be processed into paints, etc. at the manufacturing site where it is needed. Furthermore, in cases where titanium dioxide manufacturers, etc., are involved in an integrated production process from disinfectant preparation to paint manufacturing, it is not necessarily necessary to first process titanium dioxide with silver ions adsorbed thereon into a dry powder.

[0025] Although not particularly limited, the antibacterial agent can be attached to, for example, textile materials or textile products using an aqueous resin binder with a thermosetting crosslinking agent. Because silver ions are adsorbed and retained at high density on the titanium dioxide surface, re-elution is limited to a few parts per billion (ppb) even after processing into textiles, making it a highly functional antibacterial agent with long-lasting efficacy. Because silver ions are adsorbed and retained on the titanium dioxide, textile materials or textile products to which this titanium dioxide is attached can maintain their antibacterial effect for a long period of time, even in the absence of light, and are biocompatible. A biocompatible crosslinking agent, such as a polycarbodiimide crosslinking agent, can be used as the thermosetting crosslinking agent for the aqueous resin binder. For example, the use of synthetic fibers in textile materials or textile products from the perspective of cytotoxicity makes them suitable for medical textiles. Furthermore, experiments have confirmed that the antibacterial agent attached to these textile materials or textile products is retained even after washing.

[0026] Thus, by using a photocatalyst to adsorb silver ions, the bactericidal effect of the silver ions can be utilized in addition to the bactericidal effect of the photocatalyst itself, allowing the desired bactericidal effect to be maintained for a long period of time even in the absence of light. However, conventionally used ceramics such as alumina do not have the ability to adsorb silver ions. Through analysis of various photocatalysts, the inventors discovered that titanium dioxide, such as titanium dioxide with low catalytic activity used in pigments, has the property of adsorbing silver ions and retaining them stably for a long period of time. This led to the adsorption of silver onto titanium dioxide with low catalytic activity in one embodiment of the bactericide of the present invention. While various photocatalysts exist, the focus of the present invention on the silver ion adsorption function of titanium dioxide is an excellent feature not found in other silver ion-based antibacterial agents.

[0027] In the past, hydroxyapatite (HAp) particles were sometimes used as an adsorbent together with a photocatalyst, but in the antibacterial fiber material of one aspect of the present invention, an adsorbent such as hydroxyapatite is not necessary. However, in this embodiment, hydroxyapatite can also be added to the antibacterial material. As such, hydroxyapatite is not necessarily an essential component and may be omitted. However, because hydroxyapatite is well known as an adsorbent for various components, the use of hydroxyapatite is expected to enhance antibacterial activity and bacterial reduction rate.

[0028] While nanosilver has traditionally been known to have a bactericidal effect, the environmental impact of nanosilver has been a concern. The antibacterial fiber material of one embodiment of the present invention does not use nanosilver, eliminating the problem of environmental toxicity. Compared to when silver particles are used, the disinfectant of this embodiment can reduce the amount of silver used, eliminates the need to pulverize the silver particles, and eliminates the environmental impact of nanosilver, making it effective not only in terms of cost but also in terms of safety. The antibacterial fiber material of one embodiment of the present invention achieves both safety and economic efficiency by inexpensively preparing silver ion water and adsorbing silver ions onto titanium dioxide. Furthermore, the disinfectant of the present invention reliably disinfects areas that come into contact with the disinfectant because the silver ions adsorbed onto titanium dioxide are unlikely to re-leach into the liquid, while preventing unintended dissolution of silver ions, resulting in extremely high safety and environmental compatibility.

[0029] In addition, in one embodiment of the disinfectant of the present invention, titanium dioxide particles having a lower photocatalytic activity than titanium dioxide having ordinary photocatalytic activity can be used. In this case, even in the presence of light, the disinfectant can maintain at least one of the following properties: antiviral, antiallergenic, bactericidal, antifungal, or anti-odor substance properties, without adversely affecting the substrate, for example, fiber, and can appropriately extend the life of the fiber material.

[0030] Furthermore, the disinfectant of one embodiment of the present invention adsorbs silver ions onto titanium dioxide, preventing the silver ions from being re-eluted. Furthermore, since it does not contain silver particles that would generate new silver ions, it does not release unnecessary silver ions into the surrounding environment and does not pose a burden to the environment. Although silver ions of 100 ppb or less are permitted in drinking water, excessive silver ions may pose a burden to the environment. In the disinfectant of this embodiment, the silver ions are adsorbed onto titanium dioxide and are not re-eluted, so it has a continuous anti-infective effect, but the silver ions do not excessively affect the environment.

[0031] A seventh aspect of the present invention is a product coated with the paint of the sixth aspect of the present invention. Because the surface of the product is coated with a paint containing a disinfectant that provides a sustained disinfecting effect, the product exhibits a sustained disinfecting effect. Furthermore, because the disinfectant of the present invention provides a contact disinfecting effect, a sustained disinfecting effect can be achieved simply by applying a thin coating to the product surface. Because a thin coating is applied to the product surface, the amount of disinfectant used can be reduced, and the fact that the disinfectant itself is an inexpensive disinfectant and the paint containing the disinfectant is easy to apply to a coating process further enhances cost benefits.

[0032] The eighth aspect of the present invention is a product, which is a method for producing the bactericidal agent of the first aspect of the present invention, comprising the steps of: preparing a silver ion solution having a silver ion concentration selected in the range of 1 to 250 ppm by electrolysis in soft water using a silver electrode capable of vibrating; and dispersing titanium dioxide to facilitate adsorption of silver ions to the titanium dioxide in the silver ion solution. The product is characterized in that it is coated with a paint. Dispersing titanium dioxide in the silver ion solution facilitates adsorption of silver ions to the titanium dioxide in the silver ion solution. This makes it possible to support silver ions on the surface of titanium dioxide at a high density that was not possible with conventional technology.

[0033] In the prior art, nanosilver was pulverized and mixed with titanium oxide using a bead mill. In contrast, the disinfectant of the present invention only requires dispersion of titanium oxide clumps. Dispersing titanium oxide using a dispersing device increases the surface area of ​​the titanium oxide, thereby facilitating adsorption of silver ions. Furthermore, silver ions are inexpensive. While hydroxyapatite was used in the prior art to increase the amount of nanosilver adsorbed, this is unnecessary in the present invention, making it less expensive. Here, "dispersion" refers to the process of dispersing agglomerated powder in a liquid, making it fine and uniform, so that it approaches primary particles as closely as possible. In one embodiment of this aspect, titanium oxide is dispersed in a silver ion solution. The present invention is not limited to this embodiment. For example, titanium oxide can be dispersed in soft water and then mixed with a silver ion solution. Alternatively, a silver ion solution can be prepared by dispersing titanium oxide in soft water and electrolyzing silver ions in the soft water. Any dispersing device or method can be used as long as titanium oxide is dispersed in a silver ion solution.

[0034] In the step of dispersing titanium dioxide to facilitate adsorption of silver ions onto the titanium dioxide in the silver ion solution, a dispersing device for dispersing titanium dioxide in the silver ion solution may be used, a dispersing agent may be added to facilitate dispersion of titanium dioxide in the silver ion solution, or both a dispersing agent and a dispersing device may be used in combination, and any dispersing method may be used as long as it is possible to disperse titanium dioxide in the silver ion solution.

[0035] The adsorption characteristics of silver ions are due to the electrochemical properties of metals, and not all photocatalysts are good at adsorbing silver ions. Titanium oxide and hydroxyapatite adsorb silver ions, but alumina, for example, does not. The disinfectant using titanium oxide of the present invention is less expensive because it does not require hydroxyapatite. Dispersing titanium oxide allows efficient adsorption of silver ions. The disinfectant of the present invention exhibits sufficient disinfecting effect even without the use of hydroxyapatite, but the disinfectant of the present invention does not inhibit the use of hydroxyapatite, and depending on the specifications, it is possible to further add hydroxyapatite to the disinfectant.

[0036] A ninth aspect of the present invention is a manufacturing method that, in addition to the eighth aspect, further comprises a step of drying the fungicide to form a powder. A tenth aspect of the present invention is a manufacturing method for a paint that, in addition to the ninth aspect, further comprises a step of adding the fungicide to the paint. A eleventh aspect of the present invention is a manufacturing method for a product that, in addition to the tenth aspect, further comprises a step of applying the paint to a product. As a result, the manufacturing methods of the ninth to eleventh aspects can produce fungicides, paints, or products in a dried powder state that exhibit the same effects as the fourth to seventh aspects, respectively.

[0037] A twelfth aspect of the present invention is a disinfectant manufacturing apparatus that is the disinfectant manufacturing apparatus of the first aspect, characterized in that it includes an apparatus for preparing a silver ion solution and an apparatus for dispersing titanium dioxide. The disinfectant manufacturing apparatus of the twelfth aspect can appropriately manufacture a disinfectant that exhibits the same effects as the first aspect. By using an apparatus for dispersing titanium dioxide in a silver ion solution, it is possible to adsorb silver ions at a high density onto the titanium dioxide surface. In the present invention, a dispersing apparatus is used to disperse titanium dioxide in the silver ion solution, and a dispersing agent that facilitates dispersion of titanium dioxide in the silver ion solution can also be added. The synergistic effect of the dispersing agent and the dispersing apparatus makes it easier to disperse titanium dioxide in the silver ion solution.

[0038] A thirteenth aspect of the present invention relates to the disinfectant manufacturing apparatus of the twelfth aspect, and is characterized in that the apparatus for preparing the silver ion solution has two or more electrodes, at least one of which is a driving electrode provided with a driving unit, and the driving electrode is driven by the driving unit to perform at least one of vibrating, moving, and contacting with another member. The disinfectant manufacturing apparatus of the thirteenth aspect makes it possible to appropriately prepare a silver ion solution with a concentration of 1 to 250 ppm. The apparatus for preparing a silver ion solution of the present invention makes it possible to produce a silver ion solution with a high concentration of 250 ppm within 300 hours.

[0039] As described above, according to the disinfectant of one embodiment of the present invention, by adsorbing a sufficient amount of silver ions to the photocatalyst and adjusting the amount of adsorbed silver ions, it is possible to provide a disinfectant having appropriate disinfecting ability according to the application. Furthermore, the disinfectant can maintain its disinfecting effect for a long period of time even in places where light is not present, and in addition to the disinfecting effect, it has at least one property selected from the group consisting of antiviral, antiallergenic, bactericidal, antifungal, and anti-odor substance properties, and can decompose dead bodies of viruses, bacteria, mold, etc., allergens, odorous substances, and even dirt over a long period of time.

[0040] 1 is an explanatory diagram of the bactericidal function of the bactericide of this embodiment; FIG. 2 is an explanatory diagram of the bactericidal function in coating with the bactericide of this embodiment; FIG. 3 is a photograph of the experimental results of the biocompatibility of the anti-infective fiber material of this embodiment; FIG. 4 is an explanatory diagram of an experimental example of re-elution of silver ions from the bactericide of this embodiment; FIG. 5 is an explanatory diagram of an experimental example of re-elution of silver from a bactericide of a comparative example of this embodiment; FIG. 6 is an explanatory diagram of the durability of the bactericidal ability of the bactericide of this embodiment; FIG. 7 is an explanatory diagram of a silver ion electrolysis device in the bactericide manufacturing method of embodiment 2; FIG. 8 is an explanatory diagram of the use of each of the present embodiments; and FIG. 9 is an explanatory diagram of another aspect of the use of each of the present embodiments.

[0041] The following describes in detail the disinfectant, paint, product, manufacturing method, and manufacturing apparatus according to the present invention, using various experimental examples and comparative examples. However, the following embodiments are merely examples for embodying the technical concept of the present invention, and are not intended to limit the present invention to these experimental examples. The present invention is equally applicable to other embodiments falling within the scope of the claims.

[0042] [Embodiment 1] A first embodiment of the present invention will be described with reference to Figures 1 to 4. In this embodiment, an example of applying a disinfectant to fibers such as medical textiles will be described. Because the disinfectant of the present invention is composed of titanium dioxide and silver ions, it is an environmentally adaptable disinfectant and can be applied to, for example, medical textile products. When processing the disinfectant into fibers, environmentally compatible crosslinkers and binders can be selected, and the titanium oxide particle size can be adjusted to avoid nanoparticles, thereby providing environmentally adaptable infection-preventing fibers and infection-preventing textile products. However, it should be noted that the present invention is not limited to Embodiment 1 and can be used in applications where environmental adaptability is not strictly required, such as general paints. Because the disinfectant of the present invention provides a continuous disinfecting effect, it can be used in any industrial field and for any application. In addition to its disinfecting effect, the disinfectant of this embodiment utilizes titanium dioxide adsorbed with silver ions, and has at least one of excellent antiviral, antiallergenic, bactericidal, antifungal, or anti-odor properties over a long period of time, regardless of the presence or absence of light. In the following explanation, the term "antibacterial" may be used in addition to the term "sterilization." Titanium dioxide with silver ions adsorbed has a sterilizing effect, and at the same time, it also has an antibacterial effect, i.e., the effect of suppressing the growth of bacteria.

[0043] 1A is an explanatory diagram of the bactericidal function of the bactericide of this embodiment. The bactericide of this embodiment has a structure in which a high concentration of silver ions is adsorbed onto the surface of titanium dioxide, and in addition to the bactericidal effect of titanium dioxide itself as a photocatalyst, the bactericidal effect of silver ions is also added, so that it can continuously exert a high bactericidal function. The silver ions penetrate into bacteria, destroying the enzymes in the bacteria and completely killing the cells.

[0044] FIG. 1B is an explanatory diagram of the bactericidal function of a coating with the bactericide of this embodiment. Titanium oxide is dispersed in a high-concentration silver ion solution, and silver ions are adsorbed onto the titanium oxide. The titanium oxide with silver ions adsorbed in the silver ion solution is dried, for example, using a spray dryer, to produce a powdered bactericide. The bactericide is prepared as a paint containing a resin binder, and this paint is coated on the surface of a product, such as a resin film. The coating on the surface of a product, such as a resin film, contains a bactericide made of titanium oxide with adsorbed silver ions. When bacteria come into contact with this bactericide, as explained above in FIG. 1A, the bacteria are completely killed, allowing the bactericide of this embodiment to maintain an appropriate bactericidal effect for a long time. The level of this bactericidal activity can be adjusted by the concentration of the silver ion solution used in preparing the bactericide.

[0045] By producing a powdered disinfectant by drying titanium dioxide with adsorbed silver ions, the disinfectant can be easily manufactured, processed, and transported. Also, by preparing and stocking powders of various concentrations in advance, disinfectants suitable for specific applications can be stored and transported in powder form, making it possible to prepare disinfectants with the desired disinfecting ability at the work site.

[0046] Experimental Example 1: Adsorption of silver ions by titanium dioxide Titanium dioxide with low catalytic activity, for example anatase titanium dioxide used for pigments, was immersed in silver ion water obtained by electrolyzing metallic silver in pure water, and it was experimentally confirmed that silver ions are adsorbed onto the titanium dioxide. Separately, electrolysis was performed for a short period of time using a silver metal plate as the anode and a platinum metal plate as the cathode, to cause silver ions to be present in distilled water. The silver ion concentration measurements under each condition are shown in Table 1. The silver ion concentration measurement conditions were as follows: Evaluation equipment: Plasma mass spectrometer Agilent 7800, manufactured by Agilent Technologies, Inc. Centrifugation conditions: 17,000 rpm - 2 hours Ag ion measurement value: Average value of N = 3

[0047]

[0048] As shown in No. 1, silver ion water (Ag ion water) with a silver ion concentration of 7.5 ppm was prepared by electrolyzing metallic silver in pure water. As shown in No. 2, most of the silver ions in the silver ion water obtained by electrolysis were converted into titanium dioxide (TiO ２ ), and the silver ion concentration decreased from 7.5 ppm (No. 1) to 1.5 ppb (No. 2). Even when the titanium dioxide with silver ions adsorbed in No. 2 was immersed in pure water, almost no silver ions were re-eluted (see No. 3). ２ The antibacterial agent used is titanium dioxide manufactured by Shinshu Ceramic Co., Ltd., which has silver metal particles bonded to it, and it can be seen that the titanium dioxide adsorbs silver ions. ２ Although not particularly limited, the average particle size of the silver metal particles can be, for example, about 100 nm to 50 μm, the average particle size of the titanium dioxide particles can be about 100 nm to 50 μm, and the average particle size of the hydroxyapatite particles can be about 100 nm to 50 μm.

[0049] For example, the silver ion aqueous solution of No. 3 contains 35 g of titanium oxide and 65 g of 30 ppm silver ion water in 100 g of silver ion aqueous solution, and the amount of silver ions in 65 g of 30 ppm silver ion water is 46.15 mg. By adsorbing almost all of these silver ions onto titanium oxide, a disinfectant can be prepared in which 46.15 mg of silver ions are adsorbed onto 35 g of titanium oxide. To extract the disinfectant in powder form, for example, a known spray dryer can be used.

[0050] Furthermore, the silver ions adsorbed to the titanium dioxide in No. 4 were hardly re-eluted even after the titanium dioxide was immersed in pure water (see No. 5). As shown in No. 6, when 80% titanium dioxide and 20% hydroxyapatite (HAP) (slurry concentration 35%) were immersed in the silver ion water of No. 1, most of the silver ions were adsorbed by the titanium dioxide or hydroxyapatite, and it was found that the adsorbed silver ions were hardly re-eluted even when immersed in pure water (Nos. 7 and 8).

[0051] When titanium dioxide and hydroxyapatite with adsorbed silver ions are dried, some of the silver ions adsorbed in the titanium dioxide and hydroxyapatite are converted to silver hydroxide (AgOH or Ag) due to the presence of water during drying. ２ O.H. ２ O) to silver oxide (Ag ２ 0), and furthermore, in the presence of external light, a portion of the silver hydroxide or silver oxide is photodecomposed into silver atoms. That is, in a dry state, some of the silver ions adsorbed on titanium dioxide exist as silver hydroxide and silver oxide, and some also exist as additional silver metal elements in addition to the silver metal that was originally present, even if they cannot be individually observed with the naked eye. The silver ions present in each state then return to their original silver ion form with the addition of even a slight humidity, and these silver ions, together with the catalytic activity of titanium dioxide, exert an antibacterial effect.

[0052] When silver ions were adsorbed onto titanium dioxide, they were allowed to stand for a predetermined period of time. However, to achieve adsorption in a shorter period of time, manual stirring, mechanical stirring, ultrasonic irradiation, inert gas bubbling, or stirring using a ball mill can also be used.

[0053] In this embodiment, an example has been shown in which silver ions are adsorbed onto titanium dioxide or hydroxyapatite as a base material. However, gold ions (Au ３＋ ), platinum ions (Pt ２＋ ), copper ions (Cu ２＋ Although the example of supplying silver ions by electrolysis has been shown, silver ions, gold ions, platinum ions, and copper ions can be supplied by adsorbing silver nitrate (AgNO ３ ), gold chloride (AuCl ３ ), platinum chloride (PtCl ２ ), cupric chloride (CuCl ２ ) or cupric nitrate (Cu(NO ３ ) ２ ) or the like may be dissolved in an aqueous solution.

[0054] Figure 3 is an explanatory diagram of an experimental example of the re-elution of silver ions from the disinfectant of this embodiment. Figure 3A shows the appearance of the centrifuged solution obtained by centrifuging 7.5 ppm silver ion water (TiO2 slurry concentration 35 wt% mixed) after leaving it for 10 days. The concentration of re-eluted silver ions in the separated water was 1 ppb.

[0055] Figure 3B shows a comparative example, showing the results of an experiment on the re-elution of silver ions in the disinfectant of Patent Document 2, cited above as a prior art. Figure 3B shows nanosilver produced by micronizing silver particles using a bead mill with 1.7 μm silver powder. This nanosilver and hydroxyapatite were then supported on titanium oxide to prepare a disinfectant. As in Figure 3A above, the aqueous solution was mixed at a slurry concentration of 35 wt %, and the mixture was left for 10 days. The centrifuged solution was then centrifuged. The concentration of re-eluted silver ions in the separated water was 10.3 ppb.

[0056] The experiment in Figure 3 and its comparative example showed that the comparative example re-eluted 10 times as much silver ions as the disinfectant of this embodiment. The aqueous solution in Figure 3A appears white due to light reflection, but is actually an almost colorless and transparent liquid. In contrast, Figure 3B shows that nanosilver has been re-eluted into the aqueous solution, resulting in a blackish color due to chemical reactions such as the silver mirror reaction. Because the disinfectant of this embodiment is almost colorless and transparent, it does not impair the design properties of the product when used as a paint or when the paint is used on a product, for example, when coating the surface of the product.

[0057] In this way, the antibacterial material of this embodiment is produced by adsorbing silver ions onto titanium dioxide in silver ion water. The particle size of the titanium dioxide is designed to be in the range of 100 nm to 1 μm, with the weight distribution of particles 100 nm or smaller being less than 0.3%. An example of the particle size distribution of titanium dioxide used in the antibacterial agent of this embodiment is shown in Table 2.

[0058]

[0059] In Table 2, the weight distribution of particles of 100 nm (0.1 μm) or less, which is the lower limit of the particle size of titanium dioxide, is 0.2%, and the sample contains virtually no nanoparticles. The weight-average diameter is approximately 300 nm, and the particle size distribution follows a probability distribution and falls within the range of 100 nm to 600 nm. While there is no particular upper limit to the particle size of titanium dioxide, a particle size that is too large is undesirable from the standpoint of adhesion to fibrous materials, so the upper limit can be set to 1 μm, and more preferably, the upper limit can be set to approximately 600 nm. Titanium dioxide particle sizes of 100 nm or more have the advantage of being easily dispersed in aqueous resin emulsions, which are aqueous resin binders that use a thermosetting crosslinking agent.

[0060] The antibacterial material used in the disinfectant of this embodiment is white, and even when attached to textile materials, the color of the textile does not change over time, providing excellent quality stability. Titanium dioxide adsorbs electrolyzed silver ions, so it does not contain silver metal particles and therefore does not turn black due to silver metal powder.

[0061] Experimental Example 2: Biocompatibility of the Binder In Experimental Example 2, the biocompatibility of the biocide binder used in the anti-infective textile of this embodiment was confirmed. In particular, it was confirmed that it was not cytotoxic. The binder used in this embodiment is a water-based resin binder with a thermosetting crosslinker, which is a biocompatible binder. Examples of water-based resin binders include, but are not limited to, urethane resin binders, such as acrylic resin binders and polyester resin binders. A biocompatible water-based thermosetting crosslinker, such as a polycarbodiimide crosslinker, is used as the crosslinker. Because this is a biocompatible product, it does not contain preservatives. The biocide binder used in the anti-infective textile of this embodiment is biocompatible, as shown in Table 3. In this experiment, "EVAFANOL HA-207" was used as the urethane resin binder, and "NK ASSIST CI-02" was used as the thermosetting polycarbodiimide crosslinker.

[0062] In this embodiment, the biocompatibility was evaluated based on ISO 10993-5. The five grades used as the evaluation criteria are as follows: Grade 0: Reactivity=None (Scattered intracellular granules were observed. No cell lysis was observed.) Grade 1: Reactivity=Slight (Less than 20% of the cells were spherical, had weak adhesion, and had no intracellular granules. Cell lysis was observed.) Grade 2: Reactivity=Mild (More than 20% but less than 50% of the cells were spherical and had no intracellular granules. Cell lysis and intercellular voids were not observed extensively.) Grade 3: Reactivity=Moderate (More than 50% but less than 70% of the cells were spherical or lysed.) Grade 4: Reactivity=Severe (Almost all the cells were lysed.)

[0063]

[0064] [Comparative Example] Cytotoxicity of the Comparative Example Binder In contrast, the commonly available binder, U-29K binder manufactured by DIC, was found to be cytotoxic and not biocompatible. The U-29K binder contains an isocyanate-based cold-setting crosslinking agent (curing agent). For this reason, the binder was rated GRADE 4, indicating cytotoxicity.

[0065] Experimental Example 3: Washing Durability Experimental Example 3 confirmed the washability of the anti-infective textile material of this embodiment. The washing conditions for 100% domestic polyester (Tetoron) were based on the SEK Mark textile product washing method (standard selection method) of the Japan Textile Evaluation Technology Association. This washing method conforms to JIS L0217 washing method 103 and includes the following steps (1) to (5): (1) Add 40 ml of "JAFET standard blend detergent" to 30 L of water at 40°C, and fill the washing solution to the top water line of the washing tub. (2) Add the sample and, if necessary, a load of fabric to this washing solution so that the liquor ratio is 1:30, and start the washing machine. (3) After 5 minutes of treatment, stop the operation, spin-dry the sample and load of fabric in the spin-dryer, then replace the washing solution with fresh water at room temperature and rinse for 2 minutes at the same liquor ratio. (4) After rinsing for 2 minutes, the machine is stopped and the sample and the loaded fabric are dehydrated, then rinsed again for 2 minutes and dehydrated. (5) The above steps (1) to (4) are repeated a predetermined number of times. After repeated washing, the fabric is dried at 80°C or less.

[0066] The textile processing conditions are as follows (a) to (d). (a) Processing textile base fabric: 100% domestic polyester (Tetoron). (b) Bactericide: Silver ions were adsorbed onto titanium dioxide (KA-10C manufactured by Titan Kogyo) in electrolyzed silver ion water. (c) Resin binder: Aqueous urethane resin emulsion and polycarbodiimide crosslinking agent were used. No preservatives were used. (d) Textile processing conditions: The fixed amount was 4 g / m2 in solids. ２ The drying conditions were 150°C for 1 minute.

[0067] Table 4 shows the antibacterial activity of the anti-infective textile material of this embodiment against Staphylococcus aureus as a function of the number of washes. The wash-resistant antibacterial effect against Staphylococcus aureus was evaluated according to the standard. It was found that the anti-infective textile material of this embodiment can fully withstand more than 300 washes. Furthermore, while the number of Staphylococcus aureus significantly increased in the control sample upon cultivation, the number of Staphylococcus aureus in the anti-infective textile material of this embodiment after cultivation was reduced to 0.1% or less. In other words, it has a bactericidal effect of 99.99% (4 log). The bacterial species used was Staphylococcus aureus NBRC12732. In this experimental example, a test bacterial suspension containing a surfactant (Tween 80) was used. The test specimens were subjected to dry heat sterilization at 120°C for 4 hours before testing.

[0068]

[0069] Table 5 shows the antibacterial activity of the anti-infective textile material of this embodiment against E. coli as a function of the number of washes. The antibacterial effect against E. coli after washing was evaluated according to the standard, and it was found that the anti-infective textile material of this embodiment can fully withstand more than 300 washes. Furthermore, while the number of E. coli bacteria in the control sample increased significantly after cultivation, the number of E. coli bacteria in the antibacterial textile material of this embodiment after cultivation was reduced to 0.1% or less. In other words, it has a bactericidal effect of 99.99% (4 log). The bacterial species used was Escherichia coli NBRC3301.

[0070]

[0071] In conventional commercial laundry, disinfection using high-temperature steam is essential. On the other hand, the disinfectant of the present invention maintains its disinfecting effect. Therefore, sterilization using high-temperature steam is not necessary, and the disinfecting effect of the disinfectant of the present invention is sufficient. Furthermore, once the disinfectant of the present invention is applied to raw fabric, there is no need to sterilize the final product after sewing, so highly functional disinfected products can be provided at low cost.

[0072] Table 6 shows the minimum bactericidal concentration of silver ions. This shows the bactericidal effect of silver ions, which is one of the mechanisms of action of the bactericide of this embodiment, and serves as a reference for the bactericidal effect of this bactericide, for example, in the absence of light irradiation. For example, the minimum bactericidal concentration of silver ions required to achieve a bactericidal effect within 1 hour of operation is 100 ppb for Escherichia coli, 500 ppb for Staphylococcus aureus, and 10,000 ppb for Aspergillus niger.

[0073]

[0074] Experimental Example 3: Biocompatibility of Textile Materials Experimental Example 3 confirmed the biocompatibility of the textile materials used in the anti-infective textile material of this embodiment. In the field of medical textiles, stricter biocompatibility requirements are required than in normal use, and stricter standards for cytotoxicity are also required. Experimental Example 5 demonstrates the biocompatibility of 100% domestic polyester (Tetoron) along with comparative examples for various types of textile materials. Commercially available bed sheets (after washing) were used as the 100% domestic polyester (Tetoron).

[0075] In the anti-infective textile material of this embodiment, it is desirable to use synthetic fibers as the textile material from the viewpoint of biocompatibility, so that it can also be used in the field of medical textiles. Natural fibers are not necessarily guaranteed to be safe from the viewpoint of biocompatibility. Table 7 shows the results of a cytotoxicity test on 100% domestic polyester (Tetoron). Figure 2 shows photographs of the results of a biocompatibility test on the anti-infective textile material of this embodiment.

[0076] As shown in Table 7 and Figure 2, it was confirmed that the 100% domestic polyester (Tetoron) fiber material used in this experiment was not cytotoxic. As a result, it was found that the 100% domestic polyester fiber material used in this experiment met the biocompatibility standards required for medical textiles.

[0077]

[0078] In contrast, the fiber materials of Comparative Example 5-1 to Comparative Example 5-7 were found to be cytotoxic, and therefore did not meet the standard for biocompatibility in the field of medical textiles.

[0079] [Comparative Example 5-1] "Kanakin No. 3" The evaluation results for unwashed Kanakin No. 3, which is made of cotton and has traditionally been used as a standard base fabric for evaluation, showed that the unwashed 100% cotton standard base fabric for evaluation was cytotoxic, and therefore did not meet the biocompatibility standards required for medical textiles. The sample's GRADE was 4.

[0080] [Comparative Example 5-2] 100% Cotton Bed Sheet (Before Washing) The evaluation results for the unwashed 100% cotton bed sheet manufactured by T Company showed that the unwashed 100% cotton bed sheet manufactured by T Company was cytotoxic, and therefore did not meet the acceptable level of biocompatibility according to the standards in the medical textile field. The specimen's GRADE was 4.

[0081] [Comparative Example 5-3] 100% Cotton Bed Sheet (After Washing) The evaluation results for the 100% cotton bed sheet manufactured by T Company after washing showed that the 100% cotton bed sheet manufactured by T Company after washing also had cytotoxicity, and therefore did not reach the acceptable level of biocompatibility according to the standards in the medical textile field. The specimen's GRADE was 4.

[0082] Comparative Example 5-4: "Polyester and cotton blend (made in the USA)" When a polyester and cotton blend, a textile material commercially available in the USA, was evaluated, it was found to be cytotoxic and did not meet the biocompatibility standards required for medical textiles. The sample was GRADE 4.

[0083] [Comparative Example 5-5] Commercially available bed sheet made of 50% polyester and 50% cotton (after washing) Experimental Example 5 confirmed that domestically produced 100% polyester (Tetoron) fiber material is not cytotoxic. On the other hand, in Comparative Example 5-5, the cytotoxicity of a commercially available bed sheet made of 50% polyester and 50% cotton (after washing) was evaluated. The cytotoxicity of the commercially available bed sheet made of 50% polyester and 50% cotton (after washing) in Comparative Example 5-5 was found to be cytotoxic, and therefore did not meet the biocompatibility standards required by medical textiles. The specimen's Grade was 4.

[0084] [Comparative Example 5-6] 100% Cotton Bed Sheet Fabric (Surfactant-Treated Voile) manufactured by T Company. 100% cotton bed sheet fabric manufactured by T Company was washed with polysorbate-80 and sodium carbonate. As a result of the evaluation of cytotoxicity, cytotoxicity was observed even when washed with the specified formula, and the biocompatibility did not reach the acceptable level according to the standards in the medical textile field. The specimen's GRADE was 4.

[0085] Comparative Examples 5-7: Evaluation Institute's 100% Cotton Evaluation Standard Fabric (Surfactant-Treated Voile) The evaluation results for cytotoxicity of the evaluation institution's 100% cotton evaluation standard fabric washed with polysorbate-80 and sodium carbonate showed that washing with the specified formula produced a slight cleaning effect, but still exhibited cytotoxicity, and therefore the biocompatibility did not meet the standard required for medical textiles. The specimen's Grade was 3.

[0086] FIG. 4 is an explanatory diagram of the sterilization ability of this embodiment. The sterilizer of this embodiment exhibits an excellent effect not found in conventional technology, namely, a sustained sterilization effect. Conventional sterilizers, such as alcohol disinfectants, have excellent short-term sterilization effects, but the sterilization effect is not sustained. Therefore, even if the number of bacteria is reduced, the bacteria will grow again. In contrast, in products using the sterilizer of this embodiment, the sterilizer with an adjusted silver ion concentration is used to exhibit sterilization ability according to the application, and the sterilization ability persists for a long period of time, for example, 30 days or more, thereby continuously suppressing bacterial growth. This significantly reduces the risk of developing resistant bacteria. Furthermore, by using a conventional fast-acting sterilizer in combination with the sterilizer of this embodiment, the synergistic effect of the fast-acting sterilization effect and the sustained sterilization effect can be achieved, providing an extremely excellent sterilization system.

[0087] The disinfectant of this embodiment has the characteristics of having a high disinfecting effect and that the disinfecting effect is sustained, and therefore has a variety of effects such as reduced risk of infectious diseases, reduced food poisoning, reduced occurrence of resistant bacteria due to continuity, reduced price due to the absence of need to re-add disinfectant, reduced price due to the use of silver ion water, reduced environmental load due to non-elution, guaranteed safety due to biocompatibility, expanded versatility of use due to use as a paint, reduced price due to reduced washing and product life, and reduced environmental toxicity due to the absence of nanoparticles.

[0088] The disinfectant of this embodiment is a long-lasting disinfectant, and therefore, when examining the relationship between the disinfection time and the number of bacteria for Escherichia coli and Staphylococcus aureus in fibers treated with the disinfectant of this embodiment, such as blended fibers, the number of bacteria continues to decrease as the disinfection time passes, and the effect on the number of bacteria continues even after a sufficient amount of time has passed.

[0089] [Embodiment 2] A method for producing a disinfectant according to embodiment 2 of the present invention will be described with reference to Figure 5. Description of components similar to those shown in Figures 1 to 4 will be omitted. The method for producing the disinfectant of this embodiment includes the steps of: preparing a silver ion solution having a silver ion concentration selected within the range of 1 to 250 ppm by electrolysis in soft water using a silver electrode capable of vibrating; dispersing titanium dioxide; and adsorbing silver ions onto the titanium dioxide in the solution. The particle size is not limited, but may be, for example, 100 nm or more and 1 µm or less, with the weight distribution of particles of 100 nm or less being less than 0.3%.

[0090] Furthermore, a powdered disinfectant can be produced by drying the disinfectant to form a powder. Also, a disinfectant paint can be produced by adding the disinfectant to a paint. Furthermore, any product can be coated with the disinfectant paint by applying the paint to the product.

[0091] The disinfectant manufacturing device of this embodiment includes a device for preparing a silver ion solution, a device for dispersing titanium dioxide, and a device for adsorbing silver ions onto the titanium dioxide in the silver ion solution. The device for preparing the silver ion solution is not particularly limited, but may be, for example, an electrolysis device having two or more electrodes, at least one of which is a driving electrode provided with a driving unit, and which is driven by the driving unit to perform at least one of vibrating, moving, and contacting with another member.

[0092] [Preparation of Silver Ion Solution] To prepare a silver ion solution, an electrolyzer having at least one drivable silver electrode is used to electrolyze the silver ion solution in soft water. In this embodiment, a unique electrolyzer is used, which is different from conventional electrolyzers, and has two or more electrodes, for example, a pair of electrodes, at least one of which is a drive electrode provided with a drive unit, and the drive electrode can be vibrated, moved, or brought into contact with other members by the drive unit.

[0093] In an electrolysis apparatus for producing a silver ion solution by electrolysis, a DC voltage is applied between at least a pair of silver electrodes facing each other at a distance in water, for example, pure water, and silver ions (Ag) are generated from the silver electrodes. ＋ Here, the following reactions occur at the anode and cathode: Anode: Ag → Ag ＋ + e － Cathode 2H ＋ + 2e － → H ２ The chemical reaction at the anode generates silver ions (Ag) in the water. ＋ The chemical reaction on the electrode side generates hydrogen, and impurities contained in the water, such as calcium, silver chloride, and sulfide, are precipitated on the electrode surface. In conventional technology, the impurities precipitated on the electrode surface inhibit the promotion of the chemical reaction, resulting in a problem of reduced water softening efficiency.

[0094] 5 is an explanatory diagram of a silver ion electrolysis device for a disinfectant production method according to embodiment 2. The electrolysis device 10 includes an electrolytic cell 11 filled with pure water, preferably soft water, and at least one pair of electrodes, i.e., a positive electrode 20p and a negative electrode 20n, disposed opposite each other in the water of the electrolytic cell 11, a power supply 12 for applying a voltage between the positive electrode 20p and the negative electrode 20n, a power distribution unit 13 for applying a voltage output from the power supply 12 to the positive electrode 20p and the negative electrode 20n, drive units 21p and 21n for driving the positive electrode 20p and the negative electrode 20n, and drive actuators 22p and 22n as drive sources for the drive units. The positive electrode 20p and the negative electrode 20n are both silver electrodes, and a DC voltage is applied to the positive electrode 20p and the negative electrode 20n from the power supply 12 via the power distribution unit 13, causing silver ions Ag+ to elute from the silver electrodes.

[0095] The positive electrode 20p and the negative electrode 20n are driven by drive actuators 22p, 22n and drive units 21p, 21n, respectively. The drive units 21p, 21n vibrate, move, or bring the positive electrode 20p and the negative electrode 20n into contact with other members (e.g., the other electrode), thereby removing impurities adhering to the surfaces of the electrodes and effectively increasing the efficiency of silver ion electrolysis. Examples of contacting the positive electrode 20p and the negative electrode 20n with other members include contacting the other electrode or the inner wall of the electrolytic cell.

[0096] The driving pattern of the positive electrode 20p and the negative electrode 20n may be continuous, intermittent, or a combination thereof. Driving patterns include any combination of vibration patterns, movement patterns, and movement patterns that contact other components. Examples of vibration patterns include, but are not limited to, a constant 50 Hz frequency, or patterns that periodically (e.g., every second) switch between 50 Hz and other frequencies (e.g., 60 Hz). Examples of driving patterns include a pattern in which the electrodes are continuously and periodically moved toward or away from each other within a range of ΔL (e.g., approximately ±10% of L) relative to the set inter-electrode distance L. The movement pattern that contacts other components is a pattern that is combined with other patterns at a predetermined interval (e.g., once every 120 seconds) to avoid damage to the electrodes, and includes a buffering action when the electrodes contact other components.

[0097] This makes it possible to prepare any silver ion solution ranging from 1 ppm to 250 ppm. While conventional electrolysis has limited the ability to achieve a silver ion concentration of approximately 30 ppm, this embodiment makes it possible to prepare silver ion water with a high concentration of 30 ppm or more. The silver ion concentration of the silver ion solution used is approximately 1 ppm to 250 ppm, and can preferably be 30 ppm or more, 50 ppm or more, 120 ppm or less, or up to 150 ppm depending on the specifications. Furthermore, if there is no restriction of 300 hours for the preparation time, it is also possible to prepare a silver ion solution with a concentration of 250 ppm or more. The method for producing a disinfectant using such a high-concentration silver ion solution is a unique technology of this embodiment. Conventional techniques have not been able to adsorb such a high-concentration silver ion solution onto titanium oxide. Furthermore, by appropriately dispersing titanium oxide in a high-concentration silver ion solution, silver ions can be adsorbed at a high density onto titanium oxide, a feasible feat not found in conventional techniques, making this embodiment an extremely superior disinfectant.

[0098] [Titanium Oxide Dispersion Device (Homogenizer)] In order to uniformly adsorb silver ions onto titanium oxide in a silver ion solution, it is necessary to uniformly disperse titanium oxide in the silver ion solution. To uniformly disperse titanium oxide in a silver ion solution, a known homogenizer or the like can be used, and the homogenizer is not particularly limited. In this embodiment, an Econizer LABO-01 (manufactured by Sanmaru Machinery Industry Co., Ltd.) was used as an example. In this embodiment, an example of using a homogenizer in the process of dispersing titanium dioxide and facilitating adsorption of silver ions onto the titanium dioxide in the silver ion solution was described. However, this embodiment is not limited thereto. For example, a dispersing device for dispersing titanium dioxide in a silver ion solution can be used, a dispersing agent can be added to facilitate dispersion of titanium dioxide in a silver ion solution, or both a dispersing agent and a dispersing device can be used. Any dispersion method can be used as long as it can disperse titanium dioxide in a silver ion solution.

[0099] [Adsorption of silver ions onto titanium oxide] By uniformly dispersing titanium oxide in a silver ion solution using a titanium oxide dispersion device, silver ions can be adsorbed onto titanium oxide. This can be dried using a drying device such as a scree dryer to prepare a powdered fungicide, which is then used in the subsequent paint production process or the process of applying the paint to a product. Known paint production methods and paint application methods can be used in the paint production process and the process of applying the paint to a product.

[0100] The above describes various embodiments of the disinfectant, paint, product, manufacturing method, and manufacturing apparatus according to the present invention. However, these embodiments are merely examples for embodying the technical concept of the present invention, and are not intended to limit the present invention to these embodiments. The present invention may be equally applied to other embodiments falling within the scope of the claims.

[0101] FIG. 6 is an explanatory diagram of the application of each embodiment, and FIG. 7 is an explanatory diagram of another aspect of the application of each embodiment. The disinfectant of this embodiment, Abedul Ag+ (registered trademark), can be used on objects other than textile materials, such as wood, cloth, plastic, metal, ceramic, and concrete, and can also be adhered through coatings, which can also be used as internal fillers. The antibacterial agent of one embodiment of the present invention can also be used as a useful material by dispersing it in a dispersant such as water, organic solvent, adhesive, etc. Furthermore, the antibacterial agent of one embodiment of the present invention using titanium dioxide adsorbed with silver ions can also be in the form of a printing ink or paint. The disinfectant of this embodiment can be stocked in powder form with various silver ion concentrations. This powder disinfectant can be processed into paint, which can then be processed into films, fibers, coatings, etc. Furthermore, because this disinfectant has a continuous disinfecting effect, it can be used in a variety of fields, including food, medicine, and agriculture.

[0102] The disinfectant of the present invention can be applied to textiles, nonwoven fabrics, Japanese paper, films, etc., military and medical infectious diseases, aerospace, hotels and restaurants, food, cosmetics, air purification, vehicles, agriculture, forestry, fisheries, medical care, building materials, water, kitchens, air, skin diseases, pets, powder resin kneading, etc. Because the disinfectant of this embodiment has a continuous disinfecting effect, it can be further applied to a wide range of fields, including infectious disease prevention, agriculture and fisheries, aviation and space, hotels and restaurants, the military, police and fire departments, vehicles, air and water, cosmetics, textiles, nonwoven fabrics, papermaking, medical care and nursing, skin diseases, pets, powders, paints, films, coatings, building materials, and food packaging. A first embodiment will now be described. In this embodiment, the disinfectant of the present invention is composed of titanium oxide and silver ions, making it an environmentally adaptable disinfectant and therefore applicable to, for example, medical textile products. When processing textiles with the disinfectant, environmentally compatible crosslinking agents and binders are selected, and the particle size of the titanium oxide is adjusted so as not to contain nanoparticles, thereby providing environmentally adaptable infection-preventing textiles and infection-preventing textile products. In the above-mentioned embodiment 1, an example of applying the disinfectant to fibers such as medical textiles has been described, but it should be noted that the present invention is not limited to the fiber materials exemplified in embodiment 1, and can be used in a wide range of applications where environmental adaptability is not strictly required, such as general paints. The disinfectant of the present invention has a continuous disinfecting effect and can therefore be used in any industrial field and for any application.

[0103] REFERENCE SIGNS LIST 10 Electrolyzer 11 Electrolytic cell 12 Power supply unit 13 Power distribution unit 20n Negative electrode 20p Positive electrode 21p, 21n Drive unit 22p, 22n Drive actuator

Claims

1. A disinfectant containing titanium dioxide with silver ions adsorbed thereon, characterized in that the titanium dioxide adsorbs silver ions at a concentration that can be selectively selected within the range of 1 to 250 ppm, and the re-elution concentration of the silver ions is 5 ppb or less.

2. The disinfectant according to claim 1, wherein the concentration of silver ions adsorbed on the titanium dioxide is selectively selected within the range of 30 to 150 ppm.

3. The disinfectant according to claim 1, characterized in that at least a portion of the silver ions are present in the form of at least one of silver oxide, silver hydroxide and elemental silver, and in a state adsorbed on titanium dioxide.

4. The disinfectant according to claim 1, characterized in that it is in the form of a dry powder.

5. A paint containing the fungicide according to claim 4.

6. A product characterized by using the paint according to claim 5.

7. A product coated with the paint according to claim 6.

8. A method for producing the disinfectant according to claim 1, comprising the steps of: preparing a silver ion solution having a silver ion concentration selected within the range of 1 to 250 ppm by electrolysis in soft water using a silver electrode capable of vibrating; and dispersing titanium dioxide to facilitate adsorption of silver ions onto the titanium dioxide in the silver ion solution.

9. The method for producing a disinfectant according to claim 8, further comprising the step of drying the disinfectant to form a powder.

10. A method for producing a paint, comprising the method for producing a fungicide according to claim 9, further comprising the step of adding the fungicide to a paint.

11. A method for manufacturing a product, comprising the method for manufacturing a paint according to claim 10, and further comprising the step of applying the paint to a product.

12. An apparatus for producing the disinfectant according to claim 1, comprising: an apparatus for preparing a silver ion solution; and an apparatus for dispersing titanium dioxide.

13. The disinfectant manufacturing apparatus according to claim 12, characterized in that the apparatus for preparing the silver ion solution has two or more electrodes, at least one of which is a driving electrode provided with a driving unit, and the driving electrode is driven by the driving unit to perform at least one of the following driving operations: vibrating, moving, or contacting with another member.

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