JP5904524B2 - Virus inactivating agent - Google Patents

Description

  The present invention relates to a virus inactivating agent that exerts an inactivating action such as denaturation and decomposition on viruses such as influenza virus.

Conventionally, metal ions such as silver ions (Ag ⁺ ), zinc ions (Zn ²⁺ ), and divalent copper ions (Cu ²⁺ ) must suppress the growth of microorganisms or act bactericidally against microorganisms. Many antimicrobial materials in which these metal ions are supported on a substance such as zeolite or silica gel, and antimicrobial materials combined with titanium oxide having a photocatalytic action have been developed.

Regarding the antimicrobial or antiviral action of divalent copper ions, structural changes and functional destruction of cell membranes (Progress in Medicinal Chemistry, 31, pp.351-370, 1994) and metamorphic action on nucleic acids (CRC Critical Rev. Environ. Cont., 18, pp.295-315, 1989) and the action of divalent copper ions on viruses has been reported by Sangripanti et al. (Appl. Environ. Microbiol., 58, pp.3157-3162). , 1992; Appl.environ.microbiol., 59, pp.4374-4376, 1993; AIDS Res.Hum.Retrovir., 12, pp.333-336, 1996; Antimicrob.Agent Chemother., 41, pp.812- 817, 1997). In addition, a material in which the glass surface is coated with a thin film of copper (II) oxide (CuO) or a thin film containing CuO and titanium oxide (TiO ₂ ) has a phage inactivating action in the bacteriophage T4 experimental system (virus inactivation model). (Appl. Microbiol. Biotechnol., 79, pp. 127-133, 2008).

On the other hand, there have been few reports on the antimicrobial activity of monovalent copper compounds, but the antimicrobial activity of monovalent copper compounds (Cu ₂ O) against bacteria such as methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Pseudomonas aeruginosa ( MBC) has been reported to be inferior to divalent copper compounds (CuO) and metallic copper (Cu) and much weaker than silver (Ag) (International Journal of Antimicrobial Agents, 33, pp. 587-590 , 2009, especially p.589 Table 1). There is also a report on the difference in antibacterial action due to the crystalline polymorph of cuprous oxide (Chem. Commun., Pp.1076-1078, 2009), but against Bacillus, Staphylococcus aureus, Pseudomonas aeruginosa, etc. Although the bacteriostatic action (MIC) varies depending on the crystal form, it has not been reported that monovalent copper compounds have a particularly strong antibacterial action than divalent copper compounds.

As for the antiviral action of the monovalent copper compound, JP 2009-526828 A discloses nanoparticles having an antiviral action up to an average particle size of about 500 nm, and paragraph number [0020] of the publication. Describes that the nanoparticles may contain Cu ₂ O. However, the above-mentioned publication does not specifically disclose the antiviral action of Cu ₂ O itself, and those skilled in the art will be able to inactivate monovalent copper compounds against viruses based on the disclosure of the above-mentioned publication. I can't understand whether I have it or not. Also, Chinese Patent No. 101322939A describes that a coating material obtained by adding a nanometer-sized composite material of TiO ₂ / Cu ₂ O to an inorganic binder has a killing performance against bacteriophage.

  Regarding a mixture containing a monovalent copper compound and a divalent copper compound, an antiviral polymer material containing a powder mixture containing copper (I) oxide and copper (II) oxide is disclosed in JP-A-2003-528975. JP-A-2007-504291 discloses a material containing copper (I) oxide and copper (II) oxide for virus inactivation obtained by reducing divalent copper oxide.

Special table 2009-526828 Chinese Patent No. 101322939A Japanese Unexamined Patent Publication No. 2007-504291 Japanese Unexamined Patent Publication No. 2003-528975

Progress in Medicinal Chemistry, 31, pp.351-370, 1994 CRC Critical Rev. Environ. Cont., 18, pp.295-315, 1989 Appl. Environ. Microbiol., 58, pp.3157-3162, 1992 Appl.environ.microbiol., 59, pp.4374-4376, 1993 AIDS Res. Hum. Retrovir., 12, pp.333-336, 1996 Antimicrob. Agent Chemother., 41, pp.812-817, 1997 Appl. Microbiol. Biotechnol., 79, pp.127-133, 2008 International Journal of Antimicrobial Agents, 33, pp.587-590, 2009 Chem. Commun., Pp.1076-1078, 2009

  The subject of this invention is providing the virus inactivation agent which can exhibit the inactivation effect | action accompanying structural destruction, such as modification | denaturation and decomposition | disassembly, with respect to a virus.

As a result of intensive studies to solve the above problems, the present inventors have found that cuprous oxide (Cu ₂ ) compared to divalent copper compounds such as cupric oxide (CuO) and cupric sulfide (CuS). O), cuprous sulfide (Cu ₂ S), cuprous iodide (CuI), cuprous chloride (CuCl) and other monovalent copper compounds have a much stronger inactivation effect against viruses. I found out. It has also been found that a remarkable virus inactivating action is achieved even in a composition in which a photocatalytic substance such as titanium oxide or metal-supported titanium oxide is combined with a monovalent copper compound. The present invention has been completed based on the above findings.

That is, the present invention provides a virus inactivating agent containing a monovalent copper compound as an active ingredient.
According to a preferred embodiment of the present invention, the monovalent copper compound is one or more compounds selected from the group consisting of cuprous oxide, cuprous sulfide, cuprous iodide, and cuprous chloride. There is provided the above virus inactivating agent comprising the above virus inactivating agent; cuprous oxide in particulate form.

  According to another preferred embodiment, the virus inactivating agent comprising one or more photocatalytic substances together with one or more monovalent copper compounds; and the photocatalytic substance is a visible light responsive photocatalytic substance. A virus inactivating agent as described above is provided.

  According to a further preferred embodiment, the virus inactivating agent in the form of a composition containing a monovalent copper compound and a photocatalytic substance; and a mixture containing the monovalent copper compound and the divalent copper compound on the surface. The virus inactivating agent is provided as a supported photocatalytic substance.

  Furthermore, the present invention provides a virus inactivating material containing the virus inactivating agent on the surface and / or inside of the substrate. According to a preferred embodiment of the present invention, a coating agent containing the virus inactivating agent; a virus inactivating material in which the virus inactivating agent is immobilized on the substrate surface; and the virus inactivating agent using a binder Virus inactivating material immobilized on the substrate surface; virus inactivating material obtained by curing a dispersion in which the virus inactivating agent is dispersed in the resin; the resin is a natural resin or a synthetic resin The virus inactivating material is provided.

  From another point of view, according to the present invention, a method for inactivating a virus comprising the step of bringing a virus into contact with a monovalent copper compound; and a monovalent copper compound for producing the above virus inactivating agent Use of is provided.

From another point of view, the present invention provides a virus inactivating agent comprising a photocatalytic substance carrying a mixture containing a monovalent copper compound and a divalent copper compound on the surface.
According to a preferred aspect of the invention, the virus inactivating agent, wherein the photocatalytic substance is titanium oxide; the virus inactivating agent, wherein the titanium oxide is particulate titanium oxide; The virus inactivating agent as described above having a thickness of 1,000 nm; the virus inactivating agent as described above, wherein the titanium oxide particles are particles carrying a mixture of nanoclusters containing a monovalent copper compound and a divalent copper compound on the surface thereof; The virus inactivating agent is a nanocluster comprising a mixture containing an amorphous monovalent copper compound and a divalent copper compound; the nanocluster having a reducing agent in a suspension containing the divalent copper compound and titanium oxide particles The virus inactivating agent as described above, which is a nanocluster that can be prepared by adding the step; The virus inactivating agent; a monovalent copper compound is cuprous oxide, the divalent copper compound is virus inactivating agent according to any one of the above a cupric oxide is provided.

  Further, a virus inactivating material containing the virus inactivating agent on the surface and / or inside of the substrate; the virus inactivating material having the virus inactivating agent immobilized on the surface of the substrate using a binder; Provided is the above-mentioned virus inactivating material obtainable by curing a dispersion in which a virus inactivating agent is dispersed; a coating agent containing the virus inactivating agent.

The present invention also provides a photocatalytic material having a mixture containing a monovalent copper compound and a divalent copper compound supported on the surface. According to a preferred embodiment of the present invention, the photocatalytic material is titanium oxide particles, and the titanium oxide The above-mentioned photocatalytic material is provided in which the particles are particles carrying nanoclusters of a mixture containing a monovalent copper compound and a divalent copper compound on the surface thereof.
Furthermore, the present invention provides a method for producing the above-mentioned photocatalytic substance, which comprises a step of adding a reducing agent to a suspension containing a divalent copper compound and titanium oxide particles.

  The virus inactivating agent provided by the present invention can exert an inactivating action with structural destruction such as denaturation and decomposition on various viruses such as influenza virus, in addition to the light place, in the dark place. Is also characterized by its inactivation effect. Further, the inactivation action can be exhibited even in a dry state, in the presence of water, or in the presence of organic substances. For example, the virus can be efficiently inactivated over a wide range by blending it into a coating film formed from paint or floor polish, and the virus can be locally inhibited by blending it into a resin molded product such as a plastic product. It can also be activated. Furthermore, it is useful because it can exert a virus inactivating action even in the absence of visible light or ultraviolet light by being applied to a filter inside an air cleaner, a warehouse, or a refrigerator. The virus inactivating agent in which a mixture containing a monovalent copper compound and a divalent copper compound is supported on the surface of the photocatalytic substance also has an excellent effect that the virus inactivating action can be exhibited over a long period of time.

FIG. 3 is a conceptual diagram of a test method for phage inactivation ability (Example 1 and Example 2). It is the figure which showed the effect of the virus inactivation agent of this invention. In the figure, WL indicates the test result under white light irradiation, and Dark indicates the test result in a dark place. It is the figure which showed the effect of the virus inactivation agent of this invention with respect to T4 phage. It is the figure which showed the effect of the virus inactivation agent of this invention with respect to influenza virus. In the figure, WL indicates the test result under white light irradiation, and Dark indicates the test result in a dark place. It is the figure which showed the effect of the virus inactivation agent of this invention fixed to the glass substrate using the binder. It is the figure which showed the effect of the virus inactivation agent of the form of the composition containing a cuprous oxide and a photocatalytic substance. _{2 is} a scanning electron microscope image of Cu ₂ O powder used in Example 1. FIG. It is the figure which showed the method of evaluating a virus inactivation effect | action in a dry state. It is the figure which showed the effect of the virus inactivation agent of this invention in a dry state. It is the figure which showed the effect of the virus inactivation agent of this invention with respect to the sample which made gelatin coexist as an organic substance. It is the figure which showed that the virus inactivation agent of this invention exhibits a continuous inactivation effect | action when it exposes to a virus repeatedly in water. In the figure, the upper left shows the results for the Cu ₂ O shirasu balloon, and the lower right shows the results for the Cu ₂ O powder. FIG. 10 shows an X-ray diffraction (XRD) pattern and XPS (X-ray photoelectron spectroscopy) of the particles obtained in Example 9. 10 is a diagram showing an ultraviolet-visible absorption spectrum of the composite particles obtained in Example 9. FIG. FIG. 9 is a diagram showing an image obtained by observing the composite particles obtained in Example 9 with a transmission electron microscope and a result of analyzing the composition using an energy dispersive X-ray spectrometer (EDX). FIG. 10 is a view showing the results of confirming the decomposition action of 2-propanol (IPA) under irradiation of visible light on the composite particles obtained in Example 9. FIG. 10 is a view showing the results of evaluating the virus inactivating action for the composite particles obtained in Example 9. Composite particles (0.25% CuxO / TiO ₂ glucose + 8 times NaOH) For Cu _x O / TiO ₂ and Cu ₂ O + TiO ₂ physical mixture is a graph showing the results of evaluating the anti-phage performance and antibacterial effect (E. coli). FIG. 18 is a diagram showing the results of comparing the effects on Staphylococcus aureus for Cu _x O / TiO ₂ and Cu ₂ O + TiO ₂ physical mixing in the same manner as in the method obtained in FIG.

  As used herein, the term virus means DNA virus or RNA virus, but also includes bacteriophages that infect bacteria. Although the application target of the virus inactivating agent of the present invention is not particularly limited, for example, influenza virus, hepatitis virus, meningitis virus, human immunodeficiency virus (HIV), adult T cell leukemia virus, Ebola hemorrhagic fever virus, yellow fever virus, Examples include rabies virus, cytomegalovirus, severe acute respiratory syndrome (SARS) virus, varicella virus, rubella virus, poliovirus, measles virus, and epidemic parotitis virus. Preferred examples include airborne viruses such as SARS virus and influenza virus. But it is not necessarily limited to these specific aspects.

As an active ingredient of the virus inactivating agent of the present invention, one or two or more monovalent copper compounds can be used. The type of the monovalent copper compound is not particularly limited.For example, cuprous oxide (Cu ₂ O), cuprous sulfide (Cu ₂ S), or cuprous iodide (CuI), cuprous chloride (CuCl ) And the like.

As the virus inactivating agent of the present invention, a monovalent copper compound having any size and any crystal form can be used as it is, but a monovalent copper compound in a crystalline state prepared in a fine particle form by an appropriate chemical process. It is preferable to use a monovalent copper compound in the form of fine particle powder prepared by a mechanical pulverization process or the like. When the monovalent copper compound is used in the form of fine particles, the particle size of the fine particles is not particularly limited. For example, fine particles having an average particle size of about 1 nm to 1,000 μm can be used. The lower limit of the average particle diameter is preferably about 100 nm or more, more preferably about 200 nm or more, further preferably 500 nm or more, and particularly preferably 1 μm or more. The upper limit of the average particle size is not particularly limited, but is preferably 800 μm or less, more preferably 500 μm or less. For example, when using cuprous oxide (Cu ₂ O), fine particles of different crystal types can be prepared under various conditions (Chem. Commun., Pp.1076-1078, 2009) Cuprous oxide with particle size and crystal form can be used.

  Further, the monovalent copper compound is not limited to a crystalline substance, and may be any substance such as an amorphous substance, a mixture of crystals and an amorphous substance in an arbitrary ratio, or a microcrystalline substance whose periodicity is not perfect. Forms of material can be used. Moreover, the monovalent copper compound may contain a small amount of a divalent copper compound as long as the virus inactivating action is not inhibited. For example, fine particles containing monovalent copper and divalent copper in an appropriate ratio can be used as the monovalent copper compound. Therefore, the term “monovalent copper compound” used in the present specification should not be interpreted in a limited way in any sense, but should be interpreted in the broadest sense.

  The virus inactivating agent of the present specification can be used in the presence of light, such as in the presence of infrared light, in the presence of visible light, in the presence of ultraviolet light, or in the dark. In this specification, “dark place” means a state in which light does not substantially exist, and more specifically, visible light having a wavelength of about 400 to 800 nm, as well as sterilization baskets and sunlight. Ultraviolet rays (UV-C with a wavelength of 10 to 280 nm, UV-B with a wavelength of 280 to 315 nm, and UV-A with a wavelength of 315 to 400 nm) and infrared rays (with a wavelength of about 800 to 400,000 nm) It means a state that does not substantially exist.

  As the virus inactivating agent of the present invention, for example, a virus inactivating agent containing one or more kinds of monovalent copper compounds and one or more kinds of photocatalytic substances can be used. In this specification, the photocatalytic substance means a substance having a photocatalytic action, that is, a light-induced decomposition action and / or a light-induced hydrophilization action for decomposing organic substances. As the photocatalyst substance, a substance particularly excellent in the photoinduced decomposition action can be preferably used. As the photocatalytic substance, an ultraviolet light responsive photocatalytic substance or a visible light responsive catalytic substance can be used. In this way, by using a virus inactivating agent that combines a monovalent copper compound and a photocatalytic substance, while exhibiting light-induced degradation activity in the presence of ultraviolet light or visible light, it also exhibits a virus inactivating action, Furthermore, sufficient virus inactivating action can be achieved even in the dark.

  In the case where a virus inactivating agent containing a monovalent copper compound and a photocatalytic substance is used as the virus inactivating agent, the ratio of the monovalent copper compound to the photocatalytic substance is not particularly limited. A valent copper compound can be used in the range of about 0.1% to 95%. In general, a monovalent copper compound and a photocatalytic substance may be mixed at a predetermined ratio to prepare a composition.

  Hereinafter, the photocatalytic substance that can be used in combination with the monovalent copper compound in the virus inactivating agent of the present invention will be specifically described. However, the photocatalytic substance that can be used in the present invention is limited to the following specific substances. Absent.

  Among the photocatalytic substances, the ultraviolet light-responsive photocatalytic substance is a substance having a photocatalytic action in the presence of light including ultraviolet light of 400 nm or less, and a titanium oxide photocatalyst can be typically used. The photo-induced decomposition action in the titanium oxide photocatalyst is an action that causes a redox reaction with molecules adsorbed on the surface by holes and electrons generated and surface diffused by ultraviolet light excitation of 3.0 eV or more.

  Various titanium oxide photocatalysts having a photo-induced decomposition action are known. For example, titanium oxide having an arbitrary crystal structure such as anatase type, rutile type, brookite type or the like can be used. These titanium oxides can be prepared by a known method such as a gas phase oxidation method, a sol-gel method, or a hydrothermal method. Along with titanium oxide, one or two metals selected from platinum group metals such as platinum, palladium, rhodium, and ruthenium can be contained as a photocatalyst promoter. Although the usage-amount of a photocatalyst promoter is not specifically limited, For example, a photocatalyst promoter can be made into the ratio of about 1-20 weight% with respect to the total amount of a titanium oxide and a photocatalyst promoter.

  Recently, a titanium oxide catalyst doped with nitrogen (Science, 293, pp.269-271, 2001; J. Phys. Chem. B, 107) as a visible light-responsive photocatalyst that exhibits photocatalytic activity even under visible light such as room light. , pp.5483-5486, 2003; Thin Solid Films, 510, pp.21-25, 2006). Further, as a visible light responsive photocatalyst having a different structure, titanium oxide and tungsten oxide in which nanoclusters of a copper compound and / or an iron compound are supported on titanium oxide have been proposed (J. Am. Chem. Soc. , 129, pp. 9596-9597, 2007; Chem. Phys. Lett., 457, pp. 202-205, 2008; J. Phys. Chem. C., 113, pp. 10761-10766, 2009; J. Am Chem. Soc., 132, pp. 6898-6899, 2010; J. Am. Chem. Soc., 132, pp. 15259-15267, 2010). These visible light responsive photocatalysts have photocatalytic activity under visible light irradiation, for example, light rays containing light of 400 to 530 nm. These visible light responsive catalytic materials can be mixed with a monovalent copper compound and used in the form of a composition, but the visible light responsive catalytic materials are not limited to the specific catalysts described above.

  More specifically, the visible light responsive photocatalytic substance includes, for example, (A) a copper compound and / or an iron compound, and (B) a group consisting of tungsten oxide, titanium oxide, and titanium oxide whose conduction band is controlled by doping. A substance in the form of a composition comprising a combination of at least one photocatalyst selected from

  The copper compound and iron compound used as the component (A) are preferably a copper divalent salt or an iron trivalent salt that can smoothly perform electron transfer as an oxygen reduction catalyst for the photocatalyst of the component (B). Examples of the copper divalent salt and iron trivalent salt include hydrogen halide salts (hydrogen fluoride salt, hydrogen chloride salt, hydrogen bromide salt, hydrogen iodide salt), acetate salt, sulfate salt, nitrate salt and the like. . As the component (A), any one or more compounds selected from the group consisting of a copper compound and an iron compound can be used, and the component (A) is supported on the surface of the photocatalyst of the component (B). It is preferable.

  JP 2008-149312 A discloses that the combination of tungsten oxide as component (B) and a copper compound as a catalyst activity promoter as component (A) is useful as a visible light responsive photocatalyst. Tungsten oxide supporting copper ions and iron ions is useful as a visible light responsive photocatalyst, as disclosed in a bulletin photocatalyst, 28, pp.4, 2009. As a method of combining a copper compound and tungsten oxide, for example, a method of mixing about 1 to 5% by mass of CuO powder with tungsten oxide powder, a copper divalent salt (copper chloride, copper acetate, copper sulfate) For example, a polar solvent solution containing copper nitrate and the like may be added and mixed, followed by drying and firing at a temperature of about 500 to 600 ° C. to support copper ions on the tungsten oxide surface. The amount of copper ions supported can be appropriately selected in consideration of the properties of the visible light responsive photocatalyst and the like, and is not particularly limited.

  In order to prepare a visible light responsive photocatalyst using titanium oxide, it is preferable to use, for example, copper-modified titanium oxide or iron-modified titanium oxide in combination with the component (A). The crystal form of titanium oxide used as a raw material is not particularly limited. For example, titanium oxide having a crystal structure such as an anatase type, a rutile type, or a brookite type can be used.

  Examples of the copper ion species present on the surface of copper-modified titanium oxide include copper (II) chloride, copper (II) acetate, copper (II) sulfate, copper nitrate (II), copper fluoride (II), copper iodide. Copper ion species derived from (II), copper (II) bromide and the like can be used, and copper ion species derived from copper (II) chloride can be preferably used. Copper ion species are generated by a chemical reaction such as decomposition or oxidation of a copper compound such as copper (II) chloride on titanium oxide or a physicochemical change such as precipitation.

  The amount of modification by the copper ion species is not particularly limited, but for example, from the viewpoint of improving the performance of the photocatalyst, 0.05 mass% or more, preferably 0.1 mass% or more in terms of metal copper (Cu) with respect to titanium oxide, copper ion species From the viewpoint of suppressing aggregation of the photocatalyst and preventing the performance degradation of the photocatalyst, it is 0.3% by mass or less.

  Copper modified titanium oxide, for example, a step of hydrolyzing a titanium compound that produces titanium oxide in a reaction solution, and a step of surface modification of titanium oxide by mixing an aqueous solution containing a copper ion species into the solution after hydrolysis Can be manufactured.

  In the hydrolysis step, for example, an aqueous titanium chloride solution can be hydrolyzed to obtain a titanium oxide slurry, and an arbitrary crystal form can be produced by changing the conditions of the solution during hydrolysis. For example, titanium oxide particles having a brookite content of 7 to 60% by mass and brookite crystals having a crystallite size of about 9 to 24 nm can be obtained. For example, hydrolysis and aging are performed in the range of 60 to 100 ° C., and the dropping rate of the titanium tetrachloride aqueous solution is 0.6 g to 2.1 g / min, or a step of dropping hydrochloric acid 5 to 20% by mass is added, or these The process which combined these arbitrarily can be added.

  By performing the surface modification step in the range of 80 to 95 ° C., preferably in the range of 90 to 95 ° C., the copper ion species can be efficiently modified on the surface of titanium oxide. The modification of the copper ion species is, for example, the method described in the bulletin Photocatalyst, 28, pp.4, 2009. Specifically, the photocatalyst particles and copper chloride are mixed with heating in a liquid medium and then washed with water and recovered. Or a method in which photocatalyst particles and copper chloride are mixed with heating in a medium and then evaporated to dryness to recover.

  The crystal form of titanium oxide in the iron-modified titanium oxide may be any of anatase type, rutile type, brookite type, or any mixture thereof. In the case of iron-modified titanium oxide, titanium oxide having high crystallinity is preferably used, and the content of amorphous titanium oxide or titanium hydroxide is preferably small.

  Titanium oxide, the conduction band of which is controlled by doping, is a metal ion that can be expected to shift the conduction band bottom potential of titanium oxide to the positive potential side, or is isolated on the positive potential side of the conduction band bottom potential of titanium oxide. This is titanium oxide doped with metal ions that can be expected to form an effect. Examples of metal ions that can be expected to have the above effects include tungsten (VI), gallium (III), cerium (IV), germanium (IV), barium (V), and the like. You may use it in combination. Examples of preferable titanium oxide whose conduction band is controlled by doping include tungsten-doped titanium oxide and tungsten-gallium co-doped titanium oxide. A mixture in which these doped titanium oxides are combined with a copper compound or an iron compound as component (A), or a visible light responsive catalyst in which a copper divalent salt and / or an iron trivalent salt is supported on the surface of the doped titanium oxide is preferable.

  The form of titanium oxide to be doped is not particularly limited, and for example, fine particle titanium oxide or thin film titanium oxide can be used, but it is preferable to use fine particle titanium oxide having a large specific surface area. The crystal structure of titanium oxide is not particularly limited, and a rutile type, anatase type, or brookite type crystal, or any mixture thereof can be used. When titanium oxide contains a rutile crystal as a main component, the content is preferably 50% by mass or more, and more preferably 65% by mass or more. The same applies to the case where an anatase type or brookite type crystal is included as a main component.

  When doping with tungsten, the molar ratio of tungsten to titanium (W: Ti molar ratio) is preferably in the range of 0.01: 1 to 0.1: 1, preferably in the range of 0.01: 1 to 0.05: 1. More preferably, it is in the range of 0.02: 1 to 0.04: 1. When co-doping with tungsten and gallium, it is ideal that the molar ratio of tungsten to gallium (W: Ga molar ratio) is close to 1: 2, at least in the range of 1: 1.5 to 1: 2.5. Preferably, it is in the range of 1: 1.7 to 1: 2.3, more preferably in the range of 1: 1.8 to 1: 2.2. The amount of the copper divalent salt or iron trivalent salt supported on the surface of the doped titanium oxide is about 0.0001 to 1% by mass, and more preferably 0.01 to 0.3% by mass with respect to the total amount of the photocatalytic substance.

  The visible light responsive photocatalyst in which copper divalent salt and / or iron trivalent salt is supported on the surface of doped titanium oxide includes, for example, a doping step of obtaining tungsten-doped titanium oxide or tungsten-gallium co-doped titanium oxide, and copper divalent It can be produced by a metal salt loading process for loading a salt and / or iron trivalent salt.

  The doping step includes, for example, (1) a method for producing doped titanium oxide by a sol-gel method; (2) a doped titanium oxide by mixing a solution containing a tetravalent titanium salt into a dopant solution heated to a predetermined temperature. (3) A gas containing a volatile titanium compound vapor and a volatile tungsten compound vapor, or a gas containing a volatile gallium compound vapor is mixed with a gas containing an oxidizing gas by a vapor phase method. A method of producing doped titanium oxide by: and carrying titanium hexavalent salt or tungsten hexavalent salt and gallium oxide salt on the surface of titanium oxide powder, and producing doped titanium oxide by firing at a temperature of about 800 to 1,000 ° C. It can be done by the method of

  The step of supporting the copper divalent salt and / or iron trivalent salt on the surface of the doped titanium oxide is such that the copper divalent salt and / or iron trivalent salt is finely particulated and can maintain a highly dispersed state on the surface of the doped titanium oxide. It can be carried out by a method of supporting a copper divalent salt and / or iron trivalent salt as thinly as possible. In this step, preferably, the doped titanium oxide is brought into contact with an aqueous solution of copper divalent salt and / or iron trivalent salt and heated to a temperature of about 85 to 100 ° C., preferably about 90 to 98 ° C., and then filtered or filtered. It can be carried out by a method in which the solid is recovered by centrifugation or the like and sufficiently washed with water.

  As the virus inactivating agent of the present invention, a virus inactivating agent in the form of a composition containing a monovalent copper compound and a photocatalytic substance may be used. In order to achieve both high antiviral effect and photocatalytic activity, a virus inactivating agent in which a mixture containing a monovalent copper compound and a divalent copper compound is supported on the surface of the photocatalytic substance can also be used. In a preferred embodiment of the virus inactivating agent in which a mixture containing a monovalent copper compound and a divalent copper compound is supported on the surface of the photocatalytic substance, titanium oxide, more preferably titanium oxide particles can be used as the photocatalytic substance. The particle size of the titanium oxide particles is not particularly limited, but is, for example, about 5 nm to 1,000 nm. In a preferred embodiment, nanoclusters of a mixture containing monovalent copper oxide and divalent copper oxide can be formed and supported on the surface of the photocatalytic substance, preferably the photocatalytic substance particles. In this specification, the term “nanocluster” means an aggregate formed by assembling molecules of several to several hundreds of monovalent copper compounds and divalent copper compounds, but this term is limited in any sense. It should not be interpreted in a broad sense, but in the broadest sense. In general, the size of nanoclusters is a few nanometers, usually less than 10 nm. The monovalent copper compound or divalent copper compound contained in the mixture may be in a crystalline form, but may be in an amorphous state, or in a state where crystals and amorphous coexist. It is preferable that both the monovalent copper compound and the divalent copper compound are supported on the surface of the photocatalytic substance as an amorphous substance.

  For example, as a method of forming nanoclusters containing a mixture of monovalent copper oxide and divalent copper oxide on the surface of titanium oxide particles, for example, reduction to a suspension containing a divalent copper compound and titanium oxide particles The method including the process of adding an agent can be mentioned. Preferably, in a method including the step of preparing a suspension containing a divalent copper compound and titanium oxide particles and adding a reducing agent under basic conditions, for example, adjusting the pH to 9 or more, and the above method Although the method of maintaining the temperature of this suspension at 60 degreeC or more can be mentioned, it is not necessarily limited to these specific methods. The amount of nanoclusters to be supported on the particle surface of the photocatalytic substance is not particularly limited, but is, for example, about 0.01 to 10% by mass, preferably about 0.25% to 2% with respect to the mass of the photocatalytic substance such as titanium oxide. The particle size of the nanocluster is, for example, about 0.5 to 10 nm, and preferably about 2-5 nm. When the particle size of the nanocluster is 0.5 nm or less, the production becomes substantially difficult, and when it is 10 nm or more, the function as a cluster (such as electron transfer) may be deteriorated. The particle size of the nanocluster can be measured from, for example, a TEM image. In this case, the particle diameter of the photocatalytic substance, preferably titanium oxide, is, for example, about 5 to 1000 nm, preferably about 100 to 500 nm. The ratio of the monovalent copper compound to the divalent copper compound in the nanocluster is, for example, in the range of 10 to 90%, preferably in the range of 40 to 60%.

  Examples of the reducing agent include alkali metal, alkaline earth metal, aluminum, zinc, alkali metal and zinc amalgam, hydride of boron and aluminum, low oxidation state metal salt, hydrogen sulfide, sulfide, thiosulfate, At least one substance selected from the group consisting of oxalic acid, formic acid, ascorbic acid, a substance having an aldehyde bond, and an alcohol compound containing phenol can be used. Preferably, a substance having an aldehyde bond can be used as the reducing agent. As the substance having an aldehyde bond, for example, saccharide, more preferably glucose can be used, but it is not limited thereto. Saccharides are a preferred reducing agent because they are inexpensive and non-toxic, and can be easily removed by general operations such as washing after the reduction reaction. When the reaction is carried out by adjusting the suspension containing the divalent copper compound and the titanium oxide particles to be basic, the pH is generally adjusted with a metal hydroxide such as an alkali metal water such as sodium hydroxide. Although the reaction can be performed using an oxide, the reaction is not limited to the case where the reaction is performed under basic conditions.

Although the specific example of said manufacturing method is shown, this invention is not limited to this. For example, titanium oxide particles are suspended in an aqueous solution of a divalent copper compound such as CuCl ₂ and heated, for example, at 60 ° C. or higher, preferably about 90 ° C. for several hours, preferably about 1 hour, and the suspension is stirred. After the preparation, sodium hydroxide (NaOH / Cu ²⁺ = 0-8) and saccharides (for example, glucose, etc .: aldehyde compound / Cu ²⁺ = 4) are added to the suspension and further added under conditions of pH 9 or higher. The mixture is stirred at a temperature of preferably 60 ° C. or higher, more preferably about 90 ° C. for several hours, preferably about 1 hour, and the resulting solid is filtered, washed with water, and dried to dry copper oxide (Cu _X O ) Titanium oxide particles having nanoclusters supported on the surface can be prepared. The fine particles obtained by this reaction are Cu _X O (monovalent and divalent copper oxide) mainly composed of Cu ₂ O produced by the reaction represented by R-CHO + 2CU ²⁺ + 4OH ⁻ → R-COOH + Cu ₂ O + 2H ₂ O. The nanoparticle of the mixture is a composite particle in which the surface of the TiO ₂ particle is supported, and can be suitably used in the present invention as a composite particle having both a light-induced degradation action and a virus inactivation action.

  In a virus inactivating agent in which a mixture containing a monovalent copper compound and a divalent copper compound is supported on the surface of a photocatalytic substance, the divalent copper compound and titanium oxide serve as a visible light responsive photocatalyst. Visible light-responsive photocatalysts carrying a divalent copper compound on the surface are described in J. Am. Chem. Soc., 129, pp. 9596-9597, 2007 (documents cited in paragraph [0028]) Has been. At this time, the divalent copper compound receives excited electrons from the valence band of titanium oxide by interfacial charge transfer, and functions as a multi-electron reduction catalyst for oxygen to transfer electrons to oxygen. As a result, light-induced decomposition effects such as VOC resolution are exhibited under visible light irradiation. On the other hand, the monovalent copper compound supported on titanium oxide plays a role as a virus inactivating agent. Thus, the virus inactivating agent in which the mixture containing the monovalent copper compound and the divalent copper compound is supported on the surface of the photocatalytic substance has both a function as a visible light responsive photocatalyst and a function as a virus inactivating agent. There is a feature.

In addition, in the virus inactivating agent in which a mixture containing a monovalent copper compound and a divalent copper compound is supported on the surface of the photocatalytic substance, some monovalent copper compounds are divalent copper compounds due to oxygen and moisture in the air. Even when oxidized, the divalent copper compound produced by the action of the photocatalytic substance is reduced to monovalent copper, and as a result, the ability to inactivate viruses is restored. Therefore, by allowing the monovalent copper compound and the divalent copper compound to coexist on the surface of the photocatalytic substance, it becomes possible to continuously maintain the virus inactivation ability of the monovalent copper compound. As an aspect for exerting the above effect, there is an aspect in which nanoclusters of Cu _x O (a mixture of monovalent and divalent copper compounds) mainly composed of Cu ₂ O are supported on the surface of TiO ₂ particles. Particularly preferred.

  The usage form of the virus inactivating agent of the present invention is not particularly limited. For example, the virus inactivating agent is filled in an appropriate container in a solid form such as a fine powder or a granule, or used as it is, or the surface of any substrate and / or It can be used in a form containing a virus inactivating agent therein, and the latter embodiment is generally preferred. In the present specification, the “virus inactivating material” means a material containing the above-mentioned virus inactivating agent on the surface and / or inside of a substrate. Examples of the base material include, but are not limited to, a base material made of a general single member such as metal, ceramic, and glass, and a composite base material made of two or more kinds of members. . In addition, the virus-inactivating material of the present invention includes a material containing the above-described virus-inactivating agent in a coating agent that can be peeled off by appropriate means such as floor polish. Furthermore, the composite particles in which nanoclusters containing a mixture of monovalent copper oxide and divalent copper oxide are supported on the surface of the titanium oxide particles are immobilized on the film, and monovalent copper oxide and Nanoclusters comprising a mixture of divalent copper oxides can also be exposed. Alternatively, a film-like virus inactivating agent obtained by sputtering a nanocluster thin film containing a mixture of monovalent copper oxide and divalent copper oxide on the surface of thin-film titanium oxide sputtered on glass can also be used.

  Examples of the virus inactivating material in which the virus inactivating agent is immobilized on the substrate surface generally include materials in which the virus inactivating agent is immobilized on the substrate surface using an immobilizing means such as a binder. . Either an organic binder or an inorganic binder may be used as the binder, but when a composition containing a monovalent copper compound and a photocatalytic substance is used as a virus inactivating agent, the decomposition of the binder by the photocatalytic substance is avoided. Therefore, it is preferable to use an inorganic binder. The type of the binder is not particularly limited. For example, in addition to an inorganic binder such as silica that is usually used for fixing a photocatalytic substance on the substrate surface, a polymer binder that can form a thin film by polymerization or solvent volatilization, etc. Any binder can be used.

  Examples of the virus inactivating material containing the virus inactivating agent in the substrate include materials that can be obtained by curing a dispersion in which the virus inactivating agent is dispersed in a resin. As the resin, either natural resin or synthetic resin may be used. Examples include acrylic resins, phenolic resins, polyurethane resins, acrylonitrile / styrene copolymer resins, acrylonitrile / butadiene / styrene copolymer (ABS) resins, polyester resins, epoxy resins, etc., but are limited to these specific resins. It will never be done.

  The form of application of the virus inactivating agent of the present invention is not particularly limited, and can be used in the dark as well as in the presence of arbitrary light. In addition, the virus inactivating agent of the present invention can be used in the presence of water (for example, in water or seawater), in a dry state (for example, a low humidity state in winter, etc.) or in a high humidity state, or in the presence of organic matter. Has a high ability to inactivate viruses and can inactivate viruses continuously. For example, in addition to walls, floors, ceilings, etc., buildings such as hospitals and factories, machine tools and measuring devices, interiors and parts of electrical appliances (inside refrigerators, washing machines, dishwashers, etc., air cleaner filters, etc. Etc.) and can be applied to any object. Examples of dark places include, but are not limited to, application to, for example, machine interiors, refrigerator storage rooms, and hospital facilities (waiting rooms, operating rooms, etc.) that become dark places at night or when not in use. There is nothing. In addition, for example, as a countermeasure against influenza, a product in which a ceramic filter of an air washer is coated with titanium oxide and a light source for irradiating with ultraviolet rays has been proposed, but the virus inactivating agent of the present invention is used as a filter. By applying, an ultraviolet light source becomes unnecessary, and the cost can be reduced and the safety can be increased.

EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, the scope of the present invention is not limited to the following Example.
Example 1
Although the virus inactivation ability was also evaluated in influenza virus, it was confirmed by the following method mainly by model experiment using bacteriophage. A method for using the inactivation ability against bacteriophage as a model of virus inactivation ability is described in, for example, Appl. Microbiol. Biotechnol., 79, pp. 127-133, 2008, and provides reliable results. It is known.

A filter paper was laid in the deep petri dish, and a small amount of sterilized water was added. A glass plate of about 5 mm was placed on the filter paper, and a glass plate coated with a test sample such as Cu ₂ O was placed thereon. On this, 50 μL of a Qβ phage (NBRC20012) suspension that had been purified in advance and whose concentration had been clarified was dropped, and an OHP film was applied to bring the material surface into contact with the phage. The petri dish was covered with a glass plate. The same set for measurement was prepared for the number of times the number of phages was scheduled to be measured, and the set was allowed to stand in a dark place at room temperature. In addition, a 15W white fluorescent lamp (Panasonic Corporation, full white fluorescent lamp, FL15N) attached with an ultraviolet cut filter (King Manufacturing Co., Ltd., KU-1000100) is used as the light source, and the illuminance is 800 lux (illuminance meter: Each set for measurement was placed at a position to be measured with TOPCON IM-5. After a predetermined time, the phage concentration of each sample was measured. A conceptual diagram of the measurement method is shown in FIG.

The phage concentration was measured by the following method. The sample was immersed in 10 mL of a recovery solution (SM Buffer) and shaken for 10 minutes with a shaker. The phage recovery solution is diluted as appropriate and mixed with a separately cultured E. coli (NBRC13965) culture solution (OD ₆₀₀ > 1.0, 1 × 10 ⁸ CFU / mL), and then stirred in a 37 ° C. thermostatic chamber. And allowed to stand for 10 minutes to infect E. coli phage. This solution was spread on an agar medium and cultured at 37 ° C. for 15 hours, and the number of phage plaques was visually counted. The phage concentration was determined by multiplying the number of plaques obtained by the dilution factor of the phage recovery solution.

Cu ₂ O powder was finely divided in a mortar to prepare a 0.1% by mass ethanol slurry. The particle size of Cu ₂ O was 1 to 4 μm under a scanning electron microscope (SEM) (FIG. 7). In preparing the slurry, the powder was dispersed by irradiating ultrasonic waves with an ultrasonic cleaner for 20 minutes. The dispersion was dropped on the whole so as not to spill on a 2.5 cm × 2.5 cm × 1 mm (thick) glass plate, and the glass plate was placed in a constant temperature drier set at 120 ° C. and dried for 3 hours. Cu ₂ O on the obtained glass plate was 0.15 mg / 6.25 cm ² (= 0.24 g / m ² ). A CuO sample was prepared in the same manner as above, but the loading was 0.17 mg / 6.25 cm ² (= 0.27 g / m ² ) to keep the same copper ion ratio, and CuS was also 0.2 mg / 6.25 cm ² ( = 0.32 g / m ² ). Similarly, Cu ₂ S was 0.17 mg / 6.25 cm ² (= 0.27 g / m ² ), and CuI was 0.4 mg / 6.25 cm ² (= 0.64 g / m ² ). Cu ₂ S had a particle size of several tens of μm due to aggregation after refining.

The result is shown in figure 2. Although the the Cu ₂ O consisting of monovalent copper compound contacting the phage suspension for 30 minutes the phage concentration was reduced to 1/10 ⁶ the initial concentration, most inactivation effect in CuO is 30 minutes consisting of divalent copper compound Was not shown (the left figure of FIG. 2). Moreover, the phage inactivation effect of Cu ₂ O was recognized both under light irradiation (WL: white light) and in the dark (Dark). In CuS composed of a divalent copper compound, almost no inactivation effect was observed as in CuO (right diagram in FIG. 2). On the other hand, Cu ₂ S and CuI composed of monovalent copper compounds have a high phage inactivation effect similar to Cu ₂ O, and it has been confirmed that monovalent copper compounds exert a remarkable effect on phage inactivation. (Right figure in Fig. 2). Similarly, when the phage inactivation ability was examined using cuprous chloride (CuCl), it was confirmed that the phage inactivation ability was almost the same as that of cuprous oxide.

Example 2
When the virus inactivating action on T4 phage (NBRC 20004) was examined in the same manner as in Example 1, the concentration of T4 phage was reduced to 1/10 ⁶ by contacting with Cu ₂ O for 60 minutes under irradiation of white fluorescence ( (Figure 3).

Example 3
A / PR / 8/34 (H1N1) was used as an influenza virus, and the virus solution was inoculated and infected on the 12th day-old embryonated chicken eggs and cultured at 35.5 ° C. for 2 days. After allowing to stand at 4 ° C. overnight, the urine urine solution was collected and a concentrated solution was obtained by microfiltration (removal of egg-derived impurities) and ultrafiltration (impurity removal, virus concentration). This concentrated solution was purified by ultracentrifugation sucrose density gradient sedimentation rate method (5-50% sucrose linear gradient, 141,000 × g, 3 hours) to obtain a highly pure virus solution. In carrying out the test, bovine serum albumin (BSA) was added as a stabilizer to stabilize the virus.

The virus inactivating action against influenza virus was confirmed by the method shown in FIG. The support sample was prepared in the same manner as in Example 1. In the evaluation, a filter paper was laid in the deep petri dish and a small amount of sterilized water was added. A glass plate of about 5 mm was placed on the filter paper, and a glass plate (2.5 cm square) coated with a material such as Cu ₂ O was placed thereon. On top of this, 50 μL of purified influenza virus solution was dropped and covered with an OHP film to bring the material surface into contact with the virus. The petri dish was covered with a glass plate and irradiated with light. Prepare the same number of measurement sets as the number of phages to be measured, use a 20 W white fluorescent lamp (Toshiba Lighting Tech; FL20S / W) as a light source in the dark at room temperature, and illuminance of 1,000 lux (illuminance meter: The measurement set was placed at a position that was measured with TOPCON IM-5. The virus infection titer of the sample after being left in the dark for a predetermined time and after light irradiation was measured.

The glass plate inoculated with the virus after light irradiation was immersed in 5 mL of a recovery solution (PBS + 1% BSA), and recovered by shaking at 100 rpm for 10 minutes with a shaker. The collected influenza virus was diluted to 10 ^-8 cells / ml by 10-fold serial dilution, infected with each cultured MDCK cell (canine kidney-derived cell line), and cultured for 5 days at 37 ° C, CO ₂ concentration 5% . After culture, the presence or absence of cytopathic effect (CPE) of the cells was observed, and the virus infection titer (TCID ₅₀ / ml) per ml was calculated by calculating the amount of 50% cultured cells infected by the Reed-Muench method. .

The results are shown in FIG. When the influenza virus was brought into contact with CuO composed of divalent copper ions under Dark conditions, there was no change in infectivity after 30 min and no inactivation effect was shown. Similarly, when a 1000 lux white fluorescent lamp was brought into contact with CuO under irradiation conditions, the infectivity titer was not significantly reduced after 30 min, and the virus inactivating effect could not be confirmed. On the other hand, when the influenza virus was brought into contact with Cu ₂ O composed of a monovalent copper compound under Dark conditions, the infectious titration decreased in proportion to the time, and it decreased to 1/10 ³ after 30 min. . Similarly, when 1000 lux of white fluorescent lamp was irradiated and contacted with Cu ₂ O, it decreased to 1/10 ⁴ below the detection limit after 30 min. Therefore, it was confirmed that Cu ₂ O dramatically reduces the infectious titer and inactivates influenza virus under the condition of irradiating white fluorescence compared to CuO.

Example 4
Cu ₂ O powder was comminuted in a mortar, 0.1 mass% of Cu ₂ O and TEOS to a solid concentration of 0.1% (Ethyl Silicate 28, Colcoat Co., Ltd.) to prepare a hydrolyzed solution was added ethanol slurry. At that time, ultrasonic waves were irradiated for 20 minutes with an ultrasonic cleaner to disperse. Drop this dispersion over the entire 2.5 cm x 2.5 cm x 1 mm (thick) glass plate in the same manner as in Example 1 and place this glass plate in a constant temperature dryer set at 120 ° C. And dried for 3 hours. Cu ₂ O on the obtained glass plate was 0.15 mg / 6.25 cm ² (= 0.24 g / m ² ). When the phage suspension was contacted for 30 minutes in the same manner as in Example 1, the phage concentration decreased markedly, and it was confirmed that the same phage inactivation activity as in Example 1 was obtained when a binder was used. (Figure 5).

Example 5
Cu (II) / TiO ₂ and Cu ₂ O powder were finely divided in a mortar to prepare a 0.9 mass% ethanol slurry. At that time, ultrasonic waves were irradiated for 20 minutes with an ultrasonic cleaner to disperse. Drop this dispersion over the entire 2.5 cm x 2.5 cm x 1 mm (thick) glass plate in the same manner as in Example 1 and place this glass plate in a constant temperature dryer set at 120 ° C. And dried for 3 hours. Cu (II) / TiO ₂ on the obtained glass plate was 2.5 mg / 6.25 cm ² (= 4 g / m ² ), and Cu ₂ O was 0.15 mg / 6.25 cm ² (= 0.24 g / m ² ). It was. When the phage solution is contacted for 30 minutes in the same manner as in Example 1, the phage concentration is remarkably reduced, and in the form of a composition containing Cu ₂ O and a photocatalytic substance, the same phage inactivation activity as in Example 1 is obtained. (Fig. 6).

Example 6
In the evaluation of the virus inactivating action in Example 1 and the like, the humidity at the time of evaluation is about 80% or more because an evaluation system with filter paper soaked with water is used. In general, viruses are known to have low activity at high humidity and high activity at low humidity. Therefore, it was confirmed whether or not the virus inactivating agent of the present invention can maintain high activity under low humidity conditions. A conceptual diagram of the evaluation method is shown in FIG. When the amount of supported Cu ₂ O was 1/3 of Example 1 (0.08 g / m ² ) and the humidity condition was 40% or 13%, the phage concentration was reduced to 1/10 ³ times when dried. After that, it can be inactivated to below the detection limit by light irradiation for only 1 hour at a humidity of 40%, and it can be kept in contact with Cu ₂ O for 4 hours even under dark conditions with a humidity of 13%. It was possible to inactivate below the detection limit (Fig. 9). This result indicates that Cu ₂ O can exert a sufficient virus inactivating effect in a general living space such as in winter.

Example 7
Since viruses present in general living spaces coexist with various organic substances such as dust, whether or not the virus inactivating agent of the present invention can exert a sufficient inactivating action even in the presence of organic substances. investigated. A phage suspension containing 0.1% gelatin was prepared and evaluated in the same manner as in Example 1. When the amount of Cu ₂ O supported was 0.24 g / m ² , it was confirmed that a rapid virus inactivating action was exerted on a sample containing 0.1% gelatin. On the other hand, for samples containing no gelatin, the same level of virus inactivation was achieved when the Cu ₂ O loading was reduced to 1/10, and the presence of organic matter affected the virus inactivation ability. It was suggested that there is a possibility.

Example 8
As shown in FIG. 11, a shirasu balloon coated with 25 mL of phage solution suspended in 1/500 NB medium and Cu ₂ O in a waist-high petri dish (left side of the lower left photograph in the figure: 3 g Cu ₂ O / 25 mL (1/500 NB medium) )) Or Cu ₂ O powder (right side of the lower left photograph in the figure: 4 mg Cu ₂ O / 25 mL (1/500 NB medium)), and was irradiated with a white fluorescent lamp (WL) from above. The same experimental system was also placed in the dark. Sampling was performed after about 24 hours, and the phage concentration was determined. The phage concentration was reduced below the detection limit in both the WL and dark places. After sampling, phages were added again. Similarly, sampling was performed after about 24 hours, and the phage concentration was determined to be below the detection limit. Furthermore, when this operation was repeated 5 times, the inactivation effect was observed 5 times, and it was confirmed that the virus inactivation action persisted even after repeated exposure to the virus in water (Fig. 11, Cu ₂ O shirasu balloon). : Upper left, Cu ₂ O powder: lower right).

Example 9
TiO ₂ (1.0 g) was suspended in a CuCl ₂ solution (10 ml, 0.1 to ₂ Wt%) and stirred at 90 ° C. for 1 hour to prepare a suspension. Sodium hydroxide was added to the obtained suspension so that NaOH / Cu ²⁺ = 0 to 8 with respect to the number of moles of copper ions, and glucose as a reducing substance was added to glucose with respect to the number of moles of copper ions. It added so that it might become / Cu <2 ⁺ > = 4, and also it stirred at 90 degreeC for 1 hour. The solid was collected by filtration, washed with water, and dried to obtain Cu _X O—TiO ₂ . Cu _X O-TiO ₂ obtained by this reaction is composed of Cu _X O (monovalent and divalent ⁾ containing Cu ₂ O generated by the reaction represented by R-CHO + 2Cu ²⁺ + 4OH ⁻ → R-COOH + Cu ₂ O + 2H ₂ O. Composite particles in which nanoclusters containing a mixture of valence copper oxides) are supported on the surface of TiO ₂ particles. The X-ray diffraction (XRD) pattern and XPS (X-ray photoelectron spectroscopy) of the obtained particles are shown in FIG. FIG. 13 shows the ultraviolet and visible absorption spectra of the composite particles. It was confirmed that the absorption derived from Cu ₂ O increased as the amount of NaOH was increased. From this result, it was revealed that the copper compound supported on the surface of the particles was a mixture of divalent copper oxide and monovalent copper oxide.

  FIG. 14 shows the result of observation of the composite particles with a transmission electron microscope (TEM). From this result, it became clear that nanocluster-like fine particles with a particle size of about 5 nm are formed and supported on the titanium oxide surface. When the nanocluster-like particles were analyzed by an energy dispersive X-ray spectrometer (EDX), copper was detected only from the positions of the nanocluster-like particles. From these results, it was revealed that the nanocluster-like fine particles are fine particles made of a copper compound.

The obtained particles were confirmed to decompose with 2-propanol (IPA) under visible light. In a 500 mL Pyrex (registered trademark) glass vessel, place 300 mg of the powder sample in a petri dish of 5.5 cm ² and leave it still.After replacing the air in the vessel with pure air, add 6 μmol of 2-propanol, and in the dark. After standing for about 12 hours, light was irradiated with a xenon light source (400-530 nm), and the amount of CO ₂ generated was determined by gas chromatography. The obtained results are shown in FIG. Composite particles prepared with glucose showed high activity compared to Cu (II) / TiO _2. The amount of sodium hydroxide used in preparing the composite particles did not significantly affect the activity.

  A sample was prepared using the obtained particles in the same manner as in Example 1 and subjected to evaluation of virus inactivation. Complex particles prepared with 4 times the amount of copper glucose and 8 times the amount of sodium hydroxide inactivate the virus to below the detection limit both in the dark and under white light irradiation. Demonstrated (Figure 16). From the above results, it is clear that the obtained composite fine particles can be used as a material capable of exhibiting a remarkable virus inactivation activity as well as an excellent light-induced degradation activity.

Example 10
When the amount of Cu _x O / TiO ₂ in the nanocluster obtained in Example 9 was determined by ICP measurement, it was found to be 0.23% with respect to 1 g of titanium oxide. A powder obtained by simply mixing Cu ₂ O and titanium oxide so as to have the same copper content was supported on glass so as to be 0.15 mg / 6.25 cm ² (0.24 g / m ² , Cu content: 5.4 nmol). A glass in which Cu _x O / TiO ₂ powder was similarly supported on a glass was prepared, and the anti-phage performance of Cu _x O / TiO ₂ and Cu ₂ O + TiO ₂ physical mixing was compared. The results are shown in FIG. Similarly, the results of comparison for E. coli are shown in FIG. 17 (right figure). In addition, FIG. 18 shows the results of comparing the performance against S. aureus.

  Since the virus inactivating agent provided by the present invention can exert an inactivating action with structural destruction such as denaturation and decomposition on various viruses such as influenza virus, It can be applied to various uses such as filters.

Claims (10)

A virus inactivating agent comprising a visible light-responsive photocatalytic substance having a nanocluster of a mixture containing cuprous oxide and cupric oxide supported on the surface. The virus inactivating agent according to claim 1, wherein the visible light-responsive photocatalytic substance is particulate titanium oxide having a surface supporting nanoclusters of a mixture containing cuprous oxide and cupric oxide. The virus inactivating agent according to claim 2, wherein the titanium oxide particles have a particle size of 5 nm to 1,000 nm. The virus inactivating agent according to any one of claims 1 to 3, wherein the nanocluster is a nanocluster composed of a mixture containing amorphous cuprous oxide and cupric oxide. The method for producing a virus inactivating agent according to any one of claims 1 to 4, comprising a step of preparing a nanocluster by a step of adding a reducing agent to a suspension containing cupric oxide and titanium oxide particles. . The manufacturing method according to claim 5, wherein the step of adding the reducing agent to the suspension containing cupric oxide and titanium oxide particles includes the step of adding the reducing agent under basic conditions. The virus inactivation material which contains the virus inactivation agent of any one of Claims 1 thru | or 4 in the base-material surface and / or the inside. The virus inactivating material according to claim 7, comprising a virus inactivating agent immobilized on the substrate surface by a binder . The virus inactivating material according to claim 7, comprising a cured resin containing a virus inactivating agent dispersion . A coating agent comprising the virus inactivating agent according to any one of claims 1 to 4 .