Antiviral composition and antiviral member

Abstract

This invention provides an antiviral composition 1 comprising an inorganic compound 3 having antiviral properties and a porous structure. Furthermore, this invention provides an antiviral component 17 comprising a substrate 15 and the antiviral composition 1 disposed on the substrate 15. This invention provides an antiviral composition capable of adsorbing and eliminating airborne viruses onto a surface, and exhibiting excellent operability and safety, as well as an antiviral component using the antiviral composition.

Description

[Technical Field]

[0001] This invention relates to an antiviral composition and an antiviral component. [Previous Technology]

[0002] In recent years, infectious diseases caused by viruses such as COVID-19, Severe Acute Respiratory Syndrome (SARS), norovirus, and avian influenza, or bacteria such as O157, have spread rapidly in a short period of time, becoming a so-called "global pandemic." Because they threaten human lives, the whole world is eager to find countermeasures.

[0003] Therefore, the development of antibacterial and antiviral agents that can exert antibacterial and antiviral activity against various bacteria or viruses is actively underway. As illustrated in Japanese Patent Publication No. 2015-120896 (Patent Document 1), there are antiviral agents composed of inorganic oxide microparticles containing antiviral metal components such as silver, copper, and zinc.

[0004] Furthermore, as illustrated in Japanese Patent Publication No. 2000-263706 (Patent Document 2), for example, a composition containing a polymeric substance that bonds an organic antibacterial agent to the main chain or side chain, a hydrophilic substance mixed with or bonded to the aforementioned polymeric substance, and a hardener is added to plastics, fibers, etc., and used in masks, filters, coatings, etc.

[0005] Furthermore, it has been known since the past that trace amounts of metal ions such as silver, copper, and zinc have antibacterial and antifungal effects. Such antibacterial silver ions, for example, in the form of metal salts such as silver nitrate, are widely used in bactericides, disinfectants, etc. in various fields.

[0006] Any antibacterial or antiviral agent only exhibits antibacterial and antiviral activity against bacteria and viruses attached to its surface, and does not show any effect on bacteria or viruses suspended in the air. Although there are cases where chemical agents such as hypochlorous acid or hydrogen peroxide are used to eliminate pathogenic microorganisms and viruses suspended in the air, there is the issue that these chemical agents can have a significant impact on the human body or the environment. Furthermore, there is also the problem of low persistence of effect.

[0007] Furthermore, the use of metal salts is limited because they are operated in an aqueous solution state, and silver nitrate has a strong mucosal irritant effect on the human body, and its safety is also a concern.

[0008] The present invention provides an antiviral composition that can adsorb and eliminate viruses suspended in the air onto a surface, and has excellent operability and safety, as well as an antiviral component using the antiviral composition.

[0009] According to an embodiment of the present invention, an antiviral composition is provided that has an inorganic compound possessing antiviral properties and forming a porous structure. Furthermore, through another aspect of the present invention, the aforementioned inorganic compound is composed of Shirasu sand (meaning, for example, pumice or volcanic ash produced in Kyushu, Japan). [Simplified Explanation of the Diagram]

[0010] Figure 1 is a cross-sectional view of an antiviral composition according to an embodiment of the present invention, and is a schematic diagram showing the above-mentioned antiviral composition.

[0010] Figure 2 is a diagram showing an example of an antiviral component according to an embodiment of the present invention.

[0010] Figure 3 is a diagram showing an example of an antiviral component according to an embodiment of the present invention.

[0010] Figure 4 is a diagram showing an example of an antiviral component according to an embodiment of the present invention.

[0010] Figure 5 is a diagram showing the effect of the antiviral composition of an embodiment of the present invention.

[0010] Figure 6 is a diagram showing the effect of the antiviral composition of an embodiment of the present invention.

[0010] Figure 7 is a diagram showing the effect of the antiviral composition of an embodiment of the present invention.

[0010] Figure 8 is a diagram showing the effect of the antiviral composition of an embodiment of the present invention.

Implementation Method

[0011] The antiviral component 1 of the embodiment of the present invention is composed of an inorganic compound 3. The inorganic compound 3 has antiviral properties. Furthermore, as shown in FIG1, the inorganic compound 3 has a porous structure in which a plurality of micropores (bubbles) 5 are formed and a plurality of microbubbles are present.

[0012] The antiviral component 1 (inorganic compound 3) can not only adsorb viruses, but also make the adsorbed viruses disappear (deactivate).

[0013] Inorganic compound 3 possesses both antiviral and antibacterial properties. In this context, the "antiviral component" may also be referred to as an "antibacterial and antiviral component." Furthermore, the antibacterial and antiviral component 1 adsorbs both viruses and bacteria, and in order to prevent the proliferation of the adsorbed bacteria, it can kill the adsorbed bacteria (bactericidal).

[0014] Inorganic compound 3 is composed of Shirasu sand (e.g., Shirasu sand that has not undergone heat treatment or other processing). Shirasu sand 3, commonly known as white sandy deposits, is a general term for loose white volcanic ejecta and secondary deposits from which it originates, widely distributed in southern Kyushu, Japan. Shirasu sand 3 is formed by crystallization differentiation due to the cooling of high-temperature magma, causing the main components of the magma, such as SiO2, Al2O3, Fe2O3, MgO, CaO, Na2O, and K2O, to aggregate. Furthermore, Shirasu sand 3 is formed by the eruption of mineral crystals after precipitation, and consists of approximately 30% crystalline minerals and approximately 70% amorphous volcanic glass.

[0015] This amorphous volcanic glass system rapidly releases volatile components from magma, forming a porous pumice-like structure. It contains 65 to 73% SiO2, 12 to 16% Al2O3, 2 to 4% CaO, 3 to 4% Na2O, 2 to 4% K2O, and 1 to 3% iron. Furthermore, the crystalline minerals are predominantly plagioclase, with other minerals including hypersthene, quartz, pyroxene, and magnetite.

[0016] <Baizhou sand>

[0016] The Shirasu Sand System forms the Shirasu Sand Plateau. The Shirasu Sand Plateau extends from Kagoshima Prefecture in Japan to southern Miyazaki Prefecture, with a maximum thickness of 150 meters.

[0016] The Baizhou Sandy Landform was formed by the deposition of a large amount of pyroclastic flow in one go, thus forming a thick stratum without mixing with other soils. Ordinary soils are mixed with various organic matter in the powder formed by grinding rocks, due to the action of plants or microorganisms.

[0016] In contrast, the magma of the Shirasu Sandstone System became powder before it became rock, so it contains almost no nutrients (organic matter). It is a high-purity inorganic ceramic material made from magma in its ignition at ultra-high temperatures. That is, the Shirasu Sandstone System is a porous material with 60% to 80% silica content and volcanic glass as its main component.

[0017] The analytical results of Takachiho Shirasu Sand (Shirasu Sand produced in Takachiho Mountain, Kyushu, Japan) are as follows, in weight %

[0017] Loss on ignition was 2.7%, SiO2 was 67.8%, Al2O3 was 15.1%, Na2O was 3.7%, CaO was 2.2%, Fe2O3 was 2.5%, K2O was 2.2%, TiO2 was 0.27%, MnO was 0.06%, MgO was 0.58%, P2O5 was 0.03%, SO3 was 0.20%, and Cl- was less than 0.001%.

[0018] The loss on ignition based on sulfur trioxide (SO3) was determined according to JIS R5202. Silicon oxide (IV) (SiO2) was determined by agglutination gravimetric analysis. Aluminum oxide (Al2O3), iron oxide (II) (Fe2O3), titanium oxide (IV) (TiO2), calcium oxide (CaO), magnesium oxide (MgO), sodium oxide (Na2O), potassium oxide (K2O), manganese oxide (MnO), and phosphorus pentoxide (P2O5) were determined by hydrofluoric acid, nitric acid, and perchloric acid decomposition-ICP luminescence analysis. Chloride ions (Cl-) were determined by ion chromatography of the test solution according to Japan Environment Agency Notice No. 13.

[0019] Furthermore, Shirasu sand other than Takachiho Shirasu sand (e.g., Shirasu sand produced in Kagoshima) may be used to replace Takachiho Shirasu sand if it has the same composition as Takachiho Shirasu sand.

[0020] To further explain, the main components of Baizhou sand are silica and alumina, and it also contains plagioclase, quartz, titanium dioxide, etc. In addition, there are numerous tiny air bubbles within the particles of Baizhou sand.

[0021] Dry, fluffy, powdery white sand is unsuitable for paddy fields due to its poor water content, and it is prone to soil and sand flow during heavy rains, so it is considered difficult to handle.

[0022] <Inorganic compounds with antibacterial and antiviral properties>

[0022] In recent years, the antibacterial and antiviral properties of Shirasu sand have been confirmed by the redox reaction that occurs on its surface. Furthermore, although the particles of Shirasu sand 3 are not as numerous as those described later (Shirasu balloon), they contain a large number of tiny air bubbles 5. This gives Shirasu sand 3 a porous structure, allowing for physical adsorption through its micropores and mesopores, thus enabling it to adsorb viruses and other substances from the air.

[0023] Furthermore, in addition to using Shirasu sand 3, which has not undergone heat treatment or other processing, in its original state, Shirasu sand-sappanite can also be used, or both can be used together. Shirasu sand-sappanite is a micro-balloon-like substance (a hollow microparticle) formed by firing Shirasu sand at a high temperature of about 1000 degrees Celsius and causing it to foam. Moreover, Shirasu sand-sappanite has various characteristics such as being colorless, harmless, having low bulk density, being flame-retardant, having a high melting point, low thermal conductivity, high chemical resistance, high hygroscopicity, and high sound absorption. Furthermore, Figure 1 shows Shirasu sand-sappanite, which is described in detail below as inorganic compound 3.

[0024] In the antiviral composition 1, at least one additive selected from hardener, plasticizer, pigment, reinforcing agent, lubricant, antioxidant, adhesion promoter, and binder may be added to the inorganic compound 3.

[0025] When additives are added, the inorganic compound 3 is not coated with additives on the entire surface. Even with additives, since the inorganic compound (especially Shirasu sandstone) 3, which contains Shirasu sandstone that maintains its original state, becomes a porous structure with numerous bubbles 5, micropores, and mesopores, and due to the surface tension of the additives, most of the surface of the inorganic compound 3 is exposed. The additives are only coated on a small portion of the surface of the inorganic compound 3. Furthermore, the so-called surface of the inorganic compound 3 refers not only to the outer peripheral surface 7 of the inorganic compound 3 (antiviral component 1) shown in FIG. 1, but also includes the surface 9 of the voids (cavities; bubbles) 5 of the inorganic compound and the surface 13 of the pores 11 formed by the interconnection of the voids 5 of the inorganic compound 3. Furthermore, the pores 11 also connect the voids 5 of the inorganic compound to the outside of the inorganic compound 3.

[0026] The inorganic compound 3 system consists of particles with an average particle size of 250 μm or less. Further explanation: the inorganic compound 3 system is formed as particles with an average particle size of 1 μm to 250 μm or less, or 5 μm to 250 μm or less, or 10 μm to 250 μm or less, or 20 μm to 250 μm or less, or 50 μm to 250 μm or less, or 100 μm to 250 μm or less, or 150 μm to 250 μm or less. The term "average particle size" refers, for example, to the particle size representing the 50% cumulative value in the particle size distribution determined by laser diffraction or scattering methods.

[0027] However, inorganic compound 3 can also be formed into particles with an average particle size of 200 μm or less. Further, inorganic compound 3 can be in the form of particles with an average particle size of 1 μm to 200 μm or less, or 5 μm to 200 μm or less, or 10 μm to 200 μm or less, or 20 μm to 200 μm or less, or 50 μm to 200 μm or less, or 100 μm to 200 μm or less, or 150 μm to 200 μm or less. Also, when inorganic compound 3 is Baizhou sepiolite, the average particle size of the Baizhou sepiolite is preferably 145 μm (for example, 5 μm to 145 μm or less, more preferably 105 μm to 145 μm or less).

[0028] <Antiviral component>

[0028] As shown in Figure 2 or Figure 3, by disposing an antiviral component (antibacterial and antiviral component 1) on a substrate 15, an antiviral component (antibacterial and antiviral component) 17 can be obtained.

[0029] The form of the antiviral component 17 or the antiviral composition 1 is not particularly limited, and can be, for example, various shapes such as fibers, non-woven fabrics, mesh fabrics, membranes, coatings, films, sheets, blocks (see Figure 4), walls, particles, rods, plates, sponges, solutions, coatings, gels, emulsions, etc.

[0030] Preferably, it is a non-woven fabric, sheet, coating, block, wall, or particle. Also preferably, it can be used by dissolving or dispersing the antiviral component 1 in a mixture of water or an organic solvent such as alcohol and water, and then spraying it.

[0031] The antiviral component 17 (antiviral composition 1) can be formed into fibers for use as fabric. The antiviral composition 1 is applied to the surface of untreated fibers 19 (equivalent to the aforementioned substrate 15) (e.g., by using an additive such as a bonding agent to attach it), thereby creating fibers (antiviral composition-attached fibers) 21 (see Figure 2) with the antiviral composition 1 on their surface. Fabric can also be made from this fiber 21 using conventional methods. Furthermore, the antiviral composition 1 can also be attached to untreated fabric, for example, by using additives, to create a processed fabric with the antiviral composition 1 on its surface.

[0032] The above-described processed fabric can easily impart antiviral properties to ordinary fabrics. Furthermore, methods for imparting antiviral component 1 to the above-described processed fabric include, for example, impregnation, spraying, printing, coating, etc.

[0033] Regarding the above-mentioned processed fabrics, the term includes various fabric structures, not limited to woven fabrics, knitted fabrics, and non-woven fabrics. Furthermore, the materials used for fabrics may include, for example, natural fibers such as cotton, linen, and wool; regenerated fibers such as hemp; semi-synthetic fibers such as acetate and triacetate; and synthetic fibers such as polyester, nylon, acrylic acid, polypropylene, and polyethylene.

[0034] The coating material for film application may contain antiviral component 1, and the coating material for film application containing antiviral component 1 (coating material for film application containing antiviral component) 23 may be made into a processed coating (processed coating containing antiviral component) 25 (see Figure 3).

[0035] A coating material 23 containing an antiviral component and a processing coating 25 containing an antiviral component made from the coating material 23 are formed into a film and applied to a substrate 27 (equivalent to the substrate 15). This allows for easy and broad application of antiviral properties to the substrate 27. Furthermore, the processing coating 25 containing the antiviral component also includes a sheet containing the antiviral component 1.

[0036] A method for preparing a coating film 25 containing an antiviral component from a coating material 23 containing an antiviral component may include, for example, applying the antiviral component 1 to a substrate 27 by coating, spraying, or other means and then drying it. The substrate 27 may be made of materials such as paper, metal, or plastic, or may be a flat surface such as a sheet or film, or a non-flat surface such as a door handle, hanging ring, or handrail.

[0037] Furthermore, the wall covering material may also contain antiviral component 1. The wall covering material containing antiviral component 1 (wall covering material containing antiviral component) may be used, for example, for the interior and exterior walls of buildings such as residences.

[0038] Antiviral properties can be easily and broadly applied to wall coverings containing antiviral components and to interior and exterior wall surfaces made from such wall coverings. Methods for making interior and exterior wall surfaces from the aforementioned wall coverings include, for example, applying the antiviral component 1 to a substrate (the coated material) constituting the wall by coating, spraying, ironing, etc., followed by drying. As wall coverings, surface masonry, brickwork, cement mortar plastering, diatomaceous earth coating, sandblasting, tile veneer, natural wood veneer, printed decorative plywood, and decorative steel plates can be used.

[0039] Also, the uses of antiviral component 1 include, for example, wall materials, flooring materials, curtains, clothing, detergents, fabric softeners, soap, trash cans, food packaging materials, bandages, swabs, filters (air purifiers), bedding (blankets, quilts, sheets), seats (car seats, train seats, airplane seats), sponges (for cleaning, dishwashing, and filtering), diapers, cleaning tools, anti-pollution diffusion materials, sprays, etc.

[0040] Alternatively, the block-shaped antiviral component 1 shown in Figure 4 can be shaped into a suitable form and used as an indoor decoration or an outdoor monument, etc.

[0041] Here, a method for making the wall of the Satsuma Nakagiri Island using antiviral component 1 is described.

[0042] 80% (wt%) of volcanic ash white sand, 15% (wt%) of white cement or gypsum, 4% (wt%) of reinforcing materials such as straw or hemp, and 1% (wt%) of pigment coloring materials, after removing impurities and drying, are mixed with an appropriate amount of water to form a paste, thereby obtaining antiviral composition 1.

[0043] The Shirasu lacquer wall using antiviral composition 1 was also made in the same manner as the Satsuma Nakagiri Island wall using antiviral composition 1.

[0044] Further explanation: Baizhou paint wall is made by mixing 80% (wt%) of volcanic ash Baizhou sand after removing impurities and drying, 15% (wt%) of quicklime, 4% (wt%) of reinforcing materials such as rice straw or hemp, and 1% (wt%) of pigment coloring material with an appropriate amount of water to form a paste.

[0045] <Evaluation of Antiviral Components>

[0045] The obtained antiviral composition 1, used on the Satsuma Nakagiri Island wall or Shirasu lacquer wall, was applied to a substrate of approximately 12 mm thickness, such as gypsum board, veneer, concrete board, mortar waterproof plywood, or asbestos board, using a scraper to achieve a thickness of approximately 5 mm. After drying, an antibacterial and antiviral wall material was obtained. Furthermore, a 1.0 cm side square was cut from one side of the antibacterial and antiviral wall material as a test piece.

[0046] Figure 5 shows the results of the infectivity titer (phage Qβ) determination on the surface of the test strip. At the initial value, the phage infectivity titer (PFU / test strip) was approximately 106. Even over time, the wallpaper of the comparative example showed almost no phage inactivation, but the Satsuma Nakagiri Island wallpaper using antiviral component 1 or the Shirasu Urushi wallpaper using antiviral component 1 showed a reduction in phage infectivity of over 99%.

[0047] Figure 6 shows the results of the infectivity titer determination (phage Qβ) inside the test piece. A reduction in phage infectivity titer of more than 99% was found on the Satsuma Nakagiri Island wall using antiviral component 1 or the Shirasuki-kumi wall using antiviral component 1.

[0048] Figure 7 shows the results of the infectivity titer assay (feline coronavirus) on the surface of the test strip. Initially, the feline coronavirus infectivity titer (TCID50 / test strip) was between 10⁵ and 10⁶. Even over time, the wallpaper used in the comparative examples showed virtually no inactivation of feline coronavirus, but a reduction of over 98% in feline coronavirus infectivity was observed in the Satsuma Nakagiri Island wallpaper using antiviral component 1 or the Shirasu Urushi wallpaper using antiviral component 1. Also, the contact time in Figure 7 is 1 minute.

[0049] Figure 8 shows the results of the infectivity titer assay (feline coronavirus) inside the test strip. At the initial values, the feline coronavirus infectivity titer (TCID50 / test strip) was between 10⁵ and 10⁶. A reduction of over 93% in feline coronavirus infectivity titer was observed on the Samoa Nakagiri Island wall using antiviral component 1 or the Shirasuki-no-Kami wall using antiviral component 1. Also, the contact time in Figure 8 is 1 minute.

[0050] The inorganic compound 3 of the antiviral component 1 possesses antiviral properties and has a porous structure. This allows airborne viruses to be physically adsorbed onto the surface of the inorganic compound 3 (including micropores and mesopores), causing them to disappear. Furthermore, compared to the use of chemical agents such as hypochlorous acid or hydrogen peroxide, it offers superior operability and safety, causing no harm to humans or the environment, and its effects are sustained. Moreover, when the antiviral component 1 also possesses antibacterial properties, it can adsorb airborne bacteria on its surface, prevent bacterial growth, and kill the adsorbed bacteria.

[0051] Furthermore, in the antiviral composition 1, since the inorganic compound 3 is composed of Shirasu sand, the antiviral composition 1 can be manufactured inexpensively using common materials. Moreover, by using Shirasu sand, whose main components are SiO2 and Al2O3, as a material to exert antibacterial and antiviral properties, it is possible to obtain antibacterial and antiviral properties that can adsorb and eliminate bacteria or viruses suspended in the air, thereby achieving high-efficiency effects.

[0052] Furthermore, by including white sand in the antiviral component 1, the reproduction of bacteria and viruses can be inhibited. Also, compared with conventional antibacterial and antiviral materials, it has superior operability and safety.

[0053] Furthermore, in the antiviral composition 1, at least one additive selected from hardener, plasticizer, pigment, reinforcing agent, lubricant, antioxidant, adhesion promoter, and binder can be added to the inorganic compound 3. This allows for appropriate modification of the morphology of the antiviral composition 1, thereby improving its usability. Moreover, even with the addition of additives, the surface of the inorganic compound 3 remains largely exposed, thus hardly impairing the adsorption and other functions of the antiviral composition 1.

[0054] Furthermore, due to the average particle size of inorganic compound 3 being less than 250 μm, antiviral composition 1 can exert antibacterial and antiviral properties in a short time when used directly in particle form. In addition to excellent operability and safety, it can also exert excellent antibacterial and antiviral properties even in small quantities by dispersing and dissolving it in a solvent. With an average particle size of less than 250 μm, the effect can be observed within one minute of contact with the virus.

[0055] Furthermore, regarding the antiviral component 1, if the antiviral component 1 is disposed on the substrate 15, the shape of the antiviral member having the antiviral component 1 can be appropriately changed, thereby improving the usability of the antiviral component 1 (antiviral member).

[0056] The above describes the embodiments of the present invention, but the embodiments of the present invention are not limited to these, and various modifications can be made within the spirit and scope of the present invention.

[0057] According to the present invention, viruses suspended in the air can be adsorbed onto the surface and disappear, thereby providing an antiviral composition with excellent operability and safety, and an antiviral component using the antiviral composition.

Claims

1. Use of an inorganic compound in an antiviral composition, wherein the compound is used to adsorb viruses onto the surface of the inorganic compound and inactivate the adsorbed viruses, wherein, The aforementioned inorganic compound is composed of Shirasu sand with a porous structure.

2. The use as described in claim 1, wherein, The aforementioned inorganic compounds are particles with an average particle size of less than 250 μm.

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