Antiviral materials

Abstract

The present invention provides an antiviral material which has high antiviral performance, is stable, is non-toxic to organisms and the environment, and is colorless and transparent or is almost colorless and transparent. The antiviral material according to the present invention comprises a Cu-M-O compound or a Cu-M-M'-O compound, in which the Cu includes at least Cu in a monovalent state, M represents at least one element selected from the group consisting of B, Al, Sc, Ti, Co, Cr, Ni, Ga, Y, Zr, In, Rh and a lanthanoid element, and M' represents Ag or Pd.

Description

[Technical Field]

[0001] The present invention relates to an antiviral material. [Background technology]

[0002] Viruses include those that infect humans, such as avian influenza virus, norovirus, rotavirus, coronavirus, and retrovirus, as well as bacterial viruses (also called bacteriophages or phages) that infect bacteria and cause bacteriolysis.

[0003] In order to prevent viral infection, the development of antiviral materials that can exert antiviral effects is being considered, and substances containing copper (Cu), particularly monovalent copper, are known to be effective, but the mechanism by which this works has yet to be clarified.

[0004] For example, Non-Patent Document 1 suggests that copper that has diffused into the virus binds to the Vpg protein, which is part of the viral RNA polymerase, and inhibits RNA replication, or inhibits viral replication by inhibiting the enzyme that cleaves the replicated polyRNA. It also discloses that the reactive oxygen generated by copper damages the virus.

[0005] On the other hand, Non-Patent Document 2 shows that the virus inactivation ability is not reduced even in an oxygen-free environment, and the current situation is that there are many unknowns about the mechanism by which copper or monovalent copper-containing compounds inactivate viruses.

[0006] As an antiviral material containing monovalent copper, for example, Patent Document 1 discloses an antiviral agent containing, as an active ingredient, at least one monovalent copper compound selected from the group consisting of CuCl, CuOOCCH3, CuBr, CuI, CuSCN, Cu2S, and Cu2O. Furthermore, Patent Document 2 discloses a virus inactivating agent in the form of a composition containing one or more monovalent copper compounds and one or more visible light-responsive photocatalytic substances. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2014-231525 [Patent Document 2] Japanese Patent Application Publication No. 2011-153163 [Non-patent literature]

[0008] [Non-Patent Document 1] M. Vincent, Journal of Applied Microbiology, Vol. 124, 2017, pp. 1032-1046 [Non-patent document 2] Kayano Sunada, "Development, Evaluation and Processing Technology of Antibacterial and Antiviral Materials," Technical Information Association, 2013, pp. 20-26 Summary of the Invention [Problem to be solved by the invention]

[0009] The first requirement for an antiviral material is high antiviral activity. Here, "high antiviral activity" means a high ability to inactivate viruses or maintaining that inactivation ability for a long period of time. Other requirements include that the material be stable and not harmful to living organisms, including humans, or the environment. Furthermore, considering the potential for various applications, it is desirable that the material be colorless, transparent, or nearly colorless, transparent.

[0010] However, the CuCl, CuBr, CuI, and CuSCN described in Patent Document 1 are toxic and have adverse effects on aquatic organisms in particular. Cu2S and Cu2O are black and red compounds, respectively, which limits their applications. Furthermore, CuOOCCH3 decomposes in the presence of moisture to produce Cu2O, which is problematic in terms of its low stability. Furthermore, the virus inactivating agent described in Patent Document 2 has low productivity because it is necessary to prepare and mix a monovalent copper compound and a photocatalytic substance separately.Furthermore, the virus inactivating agent described in Patent Document 2 has the problem that the introduction of a photocatalyst reduces the proportion of the monovalent copper compound, thereby reducing the virus inactivation ability.

[0011] The present invention has been made in view of the above problems, and an object of the present invention is to provide an antiviral material that has high antiviral properties, is stable, is harmless to living organisms and the environment, and is colorless and transparent or nearly colorless and transparent. [Means for solving the problem]

[0012] The present inventors have made intensive efforts to solve the above problems and have found that a composite copper oxide containing monovalent copper and a specific metal element or metalloid element has high antiviral properties and is useful as an antiviral material.

[0013] The present invention provides the following <1> ~ <9> It is related to. <1> An antiviral material comprising a Cu-MO compound, wherein the Cu includes at least one univalent state, and the M is at least one element selected from the group consisting of B, Al, Sc, Ti, Co, Cr, Ni, Ga, Y, Zr, In, Rh, and lanthanoids. <2> The Cu-MO compound contains a delafossite-type crystal represented by CuMO2. <1> The antiviral material according to claim 1. <3> An antiviral material comprising a Cu-M-M'-O compound, wherein the Cu includes at least a monovalent state, the M is at least one element selected from the group consisting of B, Al, Sc, Ti, Co, Cr, Ni, Ga, Y, Zr, In, Rh, and lanthanoids, and the M' is Ag or Pd. <4> The Cu-M-M'-O compound contains a delafossite-type crystal represented by (Cu-M')MO2. <3> The antiviral material according to claim 1. <5> a substrate; and a substrate disposed on the substrate; <1> ~ <4> and a thin film comprising the antiviral material according to any one of the preceding items. <6> The aforementioned <1> ~ <4> A particle comprising the antiviral material according to any one of the above. <7> The aforementioned <6> A paint comprising the particles described in 1. <8> a substrate; and a substrate disposed on the substrate; <7> A coated body comprising a coating film made of the paint according to claim 1. <9> The aforementioned <1> ~ <4> A fiber comprising the antiviral material according to any one of the above. [Effects of the Invention]

[0014] According to the present invention, an antiviral material with high antiviral properties can be provided. The antiviral material of the present invention is stable and therefore has excellent durability and weather resistance. Furthermore, the antiviral material of the present invention is non-toxic to the human body and other organisms and does not impose a burden on the environment. Furthermore, the antiviral material of the present invention is colorless and transparent or nearly colorless and transparent, making it applicable to a variety of uses. Therefore, the antiviral material of the present invention can be applied to various products such as goggles, face shields, protective clothing, panel boards, paints for painting, and touch panel coating solutions, and can reduce contact infection with viruses. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a graph showing the results of calculations performed by first-principles calculations based on density functional theory on the relationship between the ratio of Cu in CuAlO2 substituted with Ag or Pd and the energy change in the valence band edge (VBM). [Figure 2] FIG. 2 is a graph showing the spectral transmittance of Examples 1 and 2. DETAILED DESCRIPTION OF THE INVENTION

[0016] The present invention will be described below, but the present invention is not limited to the examples in the following description. In this specification, "mass" is synonymous with "weight."

[0017] The antiviral material according to the first embodiment of the present invention is made of a Cu-MO compound, in which Cu is at least monovalent, and M is at least one element (hereinafter also referred to as a specific element) selected from the group consisting of B, Al, Sc, Ti, Co, Cr, Ni, Ga, Y, Zr, In, Rh, and lanthanoids. An antiviral material according to a second embodiment of the present invention comprises a Cu-M-M'-O compound, in which Cu is at least monovalent; M is at least one element selected from the group consisting of the specific elements, i.e., B, Al, Sc, Ti, Co, Cr, Ni, Ga, Y, Zr, In, Rh, and lanthanoids; and M' is Ag or Pd.

[0018] The present inventors have found that the compounds of the first and second embodiments have a large ionization potential, which is the energy difference between the vacuum level and the valence band maximum (VBM), and it is presumed that this will result in an antiviral material comprising such compounds having high antiviral properties. The antiviral material of the present invention can inactivate viruses and maintain this effect for a long period of time.

[0019] Although Cu and Cu oxide are known to have catalytic properties, the above-mentioned Cu-MO compound and Cu-M-M'-O compound, which are the antiviral materials of the present invention, exhibit their antiviral effects due to their own inherent antiviral ability, without relying on a photocatalytic effect.

[0020] <Antiviral material of the first embodiment> The antiviral material according to the first embodiment is preferably a delafossite crystal represented by CuMO2 (where M is the same as above). Specific examples include CuBO2, CuAlO2, CuScO2, CuTiO2, CuCoO2, CuCrO2, CuNiO2, CuGaO2, CuYO2, CuZrO2, CuInO2, and CuRhO2.

[0021] The antiviral material of the first embodiment has a higher ionization potential and therefore a higher antiviral property than conventionally disclosed CuI, etc. In particular, the delafossite-type crystal is chemically stable and therefore harmless to living organisms and the environment. Furthermore, when the specific elements include B, Al, Sc, Co, Cr, Ga, Y, In, or lanthanides, the absorption in the visible light range is small and the glass becomes nearly colorless and transparent, so there are fewer limitations on applications due to coloring.

[0022] <Antiviral material of second embodiment> The antiviral material according to the second embodiment is obtained by substituting part of the Cu in the Cu-MO compound of the first embodiment with Ag or Pd. The present inventors have found that substituting part of the Cu in the Cu-MO compound with Ag or Pd has the effect of further increasing the ionization potential.

[0023] Figure 1 shows the relationship between the substitution ratio of Cu to Ag or Pd in ​​CuAlO2 and the energy change of the valence band edge (VBM) calculated using first-principles calculations based on density functional theory. The calculation code used was CASTEP, and the Perdew-Burke-Ernzerhof generalized gradient approximation was used for the exchange-correlation potential, with norm-conserving pseudopotentials for each element. The plane wave cutoff energy was set to 925 eV. The density of states (DOS) was calculated by substituting Ag or Pd for Cu at any ratio in a 3x3x1 supercell. The change in the VBM was evaluated based on the energy of the DOS, which is mainly composed of oxygen 2s orbitals.

[0024] Figure 1 shows that when Cu is substituted with either Ag or Pd, a stable crystal structure is maintained up to a substitution rate of 33 atomic %, as calculated. Furthermore, as Cu is substituted with Ag or Pd, the VBM takes on deeper energy in both cases, increasing the ionization potential. This makes it possible to enhance antiviral properties.

[0025] To further enhance the effects of the present invention, the substitution rate of Cu with Ag or Pd is preferably 3 atomic % or more, more preferably 10 atomic % or more, and even more preferably 20 atomic % or more. In consideration of maintaining the Cu atomic weight and the crystal structure, the upper limit of the substitution rate of Cu with Ag or Pd is preferably 80 atomic % or less, more preferably 60 atomic % or less, and even more preferably 40 atomic % or less.

[0026] The antiviral material according to the second embodiment is preferably a delafossite-type crystal represented by (Cu-M')MO2 (M and M' are the same as above). Specifically, the delafossite-type crystals include (Cu-Ag)BO2, (Cu-Pd)BO2, (Cu-Ag)AlO2, (Cu-Pd)AlO2, (Cu-Ag)ScO2, (Cu-Pd)ScO2, (Cu-Ag)TiO2, (Cu-Pd)TiO2, (Cu-Ag)CoO2, (Cu-Pd)CoO2, (Cu-Ag)CrO2, (Cu-Pd)Cr ... Cu-Ag)NiO2, (Cu-Pd)NiO2, (Cu-Ag)GaO2, (Cu-Pd)GaO2, (Cu-Ag)YO2, (Cu-Pd)YO2, (Cu-A g) ZrO2, (Cu-Pd)ZrO2, (Cu-Ag)InO2, (Cu-Pd)InO2, (Cu-Ag)RhO2, (Cu-Pd)RhO2, etc.

[0027] As described above, the delafossite-type crystal is chemically stable and therefore harmless to living organisms and the environment. Furthermore, when the specific elements include B, Al, Sc, Co, Cr, Ga, Y, In, or lanthanides, the absorption in the visible light range is small and the glass becomes nearly colorless and transparent, so there are fewer limitations on applications due to coloring.

[0028] <Antiviral particles> The antiviral material of the present invention can be obtained in particulate form. The particles can be obtained by common inorganic particle production methods, such as solid-state reaction, hydrothermal, sol-gel, liquid-phase combustion, and thermal plasma. These methods are similar in that Cu, M, and O, or Cu, M, M', and O, are mixed in a stoichiometric ratio and reacted. However, the starting materials and the size of the resulting particles differ for each method. Furthermore, by selecting the appropriate conditions, each process can produce CuMO2 or (Cu-M')MO2 crystals.

[0029] Below, each production method will be explained using the production of a Cu-MO compound as an example, but the same applies to the production of a Cu-M-M'-O compound.

[0030] (Solid-state reaction method) In the solid-state reaction method, powders of oxides of Cu and M contained in the target Cu-MO compound or powders of double oxides of Cu and M are used as starting materials, and they are mixed so as to achieve the stoichiometry of the target compound. In this case, it is best to use Cu containing a monovalent oxidation state such as Cu2O.

[0031] There are no particular restrictions on the method for mixing the oxide powders, and a ball mill is generally used, regardless of whether it is a dry or wet method. However, if a wet method is used, it is necessary to select a liquid in which the raw oxides do not dissolve.

[0032] The powder mixed by any method such as ball milling is placed directly or formed into tablets, which are then placed in a crucible made of aluminum oxide, magnesium oxide, yttrium oxide-stabilized zirconium oxide, etc. and fired for at least two hours. The type of crucible should be selected appropriately so that it does not react with the mixed powder of raw materials at the firing temperature.

[0033] The firing temperature is generally about 900 to 1200° C., and can be selected arbitrarily depending on the target compound. In order to avoid changing the oxidation state of monovalent Cu, the firing is preferably carried out in an inert gas atmosphere with the oxygen partial pressure as low as possible, such as carbon dioxide gas (CO2), nitrogen gas (N2), or argon gas (Ar), or in a vacuum.

[0034] By firing at an appropriate temperature, a solid-state reaction occurs between the raw material powders, resulting in the desired Cu-MO compound. Because the solid-state reaction method is carried out at a relatively high temperature, the product may grow and sinter, and the size of the particles obtained by this method depends on the subsequent re-grinding process. When particles are generated by re-grinding using a typical ball mill or homogenizer, the size of the resulting particles is approximately 1 to 10 μm.

[0035] (hydrothermal method) In the hydrothermal method, a Cu halide (Cu-h) such as CuCl and a double oxide (AMOx) of a metal M and an alkali metal such as NaMOx are used as starting materials. Cu-h and AMOx in the stoichiometric amounts for the target Cu-MO compound are dissolved in an aqueous alkali metal hydroxide solution using the same alkali metal as the alkali metal in the AMOx composition, homogenized, and then loaded into an autoclave and heated at an arbitrary temperature of around 300 to 400°C for about 5 hours to obtain a precipitate.

[0036] The precipitate is washed in this order with dilute hydrochloric acid solution, dilute ammonia solution, pure water, ethanol, etc., and then dried to obtain the desired Cu-MO compound powder. Because there is no high-temperature firing process, particles of approximately 1 to 2 μm in size are obtained.

[0037] (Sol-gel method) In the sol-gel method, nitrates of Cu and M contained in the target Cu-MO compound are used as starting materials. These compounds are dissolved in pure water according to the stoichiometry of the target compound, and citric acid is added to produce a metal citrate complex. Ethylene glycol is then added and the mixture is stirred for about two hours at a temperature of 25 to 200°C, yielding a gel-like precursor in which Cu and M are mixed at the atomic level.

[0038] This gel precursor is heated in the atmosphere at an arbitrary temperature of about 300 to 400°C for about 2 to 10 hours to obtain a primary powder.

[0039] As with the solid-state reaction method, the target Cu-MO compound can be obtained by firing this primary powder in an inert gas atmosphere or in a vacuum at a temperature of approximately 750-1200°C. With the sol-gel method, Cu and M are mixed at the atomic level in the primary powder before firing, so the target compound can be obtained even with firing at a lower temperature than with the solid-state reaction method, and particles 30-70 nm in size can be produced. It should be noted that the particle synthesis method using the sol-gel method is not limited to the materials and processes shown here.

[0040] (Liquid Phase Combustion Method) In the liquid phase combustion method, nitrate hydrates of Cu and M contained in the target Cu-MO compound are used as starting materials. These compounds are dissolved in pure water in the stoichiometric proportions of the target compounds, and then hexamine or the like, which acts as an oxidizer and fuel, is added and stirred.

[0041] The resulting solution is transferred to a crucible made of aluminum oxide, magnesium oxide, yttrium oxide-stabilized zirconium oxide, etc., and then heated and burned using a hot plate or electric furnace. Burning is carried out at 300 to 600°C until the liquid phase disappears, and the resulting precursor is then fired, or the precursor may be transferred to an electric furnace at any temperature once combustion has begun and fired as is. The latter method requires temperatures of 1000°C or higher to obtain the desired Cu-MO compound, and therefore the particle size obtained is approximately 1-10 μm, similar to that obtained by the solid-state reaction method. In the former method, by appropriately setting the combustion temperature, the precursor composition can sometimes become a mixture of Cu2O and MOx, and this precursor can become a Cu-MO compound when fired at approximately 800°C. In the former method, the low temperature suppresses particle growth, resulting in sub-μm particles.

[0042] (thermal plasma method) The thermal plasma method is a method of vaporizing raw materials using plasma to obtain the desired substance. The size of the substance can be controlled by the concentration of the vaporized raw material, and the particle size can be controlled from nano-size to micron-size and even larger. The plasma source can be a high-frequency plasma.

[0043] The raw material is an oxide powder of Cu or M contained in the target Cu-MO compound, or a double oxide powder of Cu and M. This is introduced into the plasma chamber either as powder or dispersed in ethanol or the like.

[0044] The powder is vaporized in the plasma chamber and condenses to produce the Cu-MO compound, but the desired compound can be obtained by appropriately selecting the amount of each raw material added. In addition to maintaining the plasma by introducing inert gas such as Ar, the composition can be adjusted by introducing oxygen or hydrogen.

[0045] The particles formed by agglomeration are cooled in a cooling zone provided at the bottom of the chamber and then collected using a bag filter or the like.

[0046] (Electrospinning) Cu acetate and M and M' nitrates can be used for electrospinning, and when they are used to form an antiviral material, the shape of the antiviral material is fibrous with a diameter of about sub-micron.

[0047] In the electrospinning method, the acetate salt of Cu and the nitrate salt of M are dissolved in dimethylformamide (DMF) according to the stoichiometry of the desired Cu-MO compound and stirred for approximately one hour. Polyvinylpyrrolidone is then added, and the mixture is stirred for another 12 hours or so before being loaded into an electrospinning syringe. After electrospinning, the voltage between the syringe and the substrate is set to approximately 15 kV, and the intermediate product is peeled off from the substrate. After drying the intermediate product, it is calcined and fired to obtain a fibrous Cu-MO compound.

[0048] The drying temperature may be selected from 80 to 200°C, the calcination temperature from 400 to 600°C, and the firing temperature from 900 to 1200°C, and the holding time may be selected from about 10 minutes to 5 hours.

[0049] <Antiviral thin film> The antiviral material of the present invention can also be obtained in the form of a thin film. A thin film containing the antiviral material of the present invention has high antiviral properties.

[0050] The thin film can be obtained as a laminate in which the substrate and the thin film are integrated by forming a film containing the antiviral compound of the present invention on a substrate.

[0051] A method for forming a thin film on a substrate includes, for example, a dry coating method.

[0052] (Dry coating method) The dry coating method uses a vacuum to form a thin film of antiviral material on the surface of a substrate. Examples of the dry coating method include magnetron sputtering, vacuum deposition, ion beam assisted deposition, and ion beam sputtering.

[0053] The substrate is not particularly limited, and examples thereof include glass, organic resin, etc. Among these, transparent substrates made of glass, organic resin, etc. are preferred. Examples of the glass include soda lime glass and laminated glass, which are mainly used for plate glass and automotive glass, and examples of the organic resin include resins such as polycarbonate, acrylic, polyethylene, polypropylene, and polyethylene terephthalate. The shape of the substrate is not limited to a flat plate, and may have a curvature over the entire surface or in part.

[0054] In the magnetron sputtering method, for example, a thin film made of the antiviral material of the present invention (Cu-MO compound, Cu-M-M'-O compound) is formed by any of the following methods (1) to (4). (1) While heating, copper and metals other than copper are sequentially deposited on the surface of the substrate. (2) Copper and metals other than copper are sequentially deposited on the surface of the substrate, followed by heat treatment. (3) While heating, copper and metals other than copper are simultaneously attached and deposited on the substrate surface. (4) Copper and metals other than copper are simultaneously attached and deposited on the surface of the substrate, and then heat treated.

[0055] A method for producing a thin film (antiviral film) containing a Cu-MO compound by magnetron sputtering will be described below. The same method applies to a thin film containing a Cu-M-M'-O compound.

[0056] Method (1) Place the substrate in the chamber of a magnetron sputtering system equipped with a pure copper target, 5.0 × 10 -4 The chamber is evacuated to a vacuum of 5.0×10 Pa or less. Then, the substrate in the chamber is heated to 200 to 500° C. and maintained at this temperature. Note that the pressure in the chamber increases due to heating, so the pressure in the chamber is increased to 5.0×10 -4 Further evacuate to a vacuum of 0.1 Pa or less.

[0057] After heating and evacuation, argon gas and oxygen gas are introduced, a pulsed DC voltage is applied to the target to generate plasma, and a copper oxide compound is produced on the substrate by magnetron sputtering. The voltage applied to the target here may be DC, RF, or AC (bipolar alternating current). The target material may be copper oxide. When the target is made of copper oxide with a high proportion of Cu2O, which has high electrical resistance, RF is selected as the power source.

[0058] M, a metal other than copper, is processed into thin plate-like chips and uniformly placed on the target. The desired composition is adjusted by the number and position of the chips. After deposition, the sample can be removed and reheated to adjust the crystallinity of the CuMO2.

[0059] Method (2) Place the substrate in the chamber of a magnetron sputtering system equipped with a pure copper target, 5.0 × 10 -4 The chamber is evacuated to a vacuum of 0.1 Pa or less. Argon gas and oxygen gas are then introduced, and a pulsed DC voltage is applied to the pure copper target to generate plasma, and a copper oxide compound is produced on the substrate by magnetron sputtering. The voltage applied here may be DC, RF, or AC (bipolar alternating current). The target material may be copper oxide. When the target is a copper oxide with a high proportion of CuO, which has high electrical resistance, RF is selected as the power source.

[0060] M, a metal other than copper, is uniformly placed on the target as chips processed into thin plates. The desired composition is adjusted by the number and position of the M to be placed. In addition to placing M as chips, a Cu-M alloy material target may be used, or Cu and M targets may be prepared separately and uniformly attached to a backing plate.

[0061] After film formation, the substrate is removed from the chamber and heated at atmospheric pressure at 200 to 500°C for 5 to 120 minutes. Furthermore, the sample may be removed and reheated under conditions different from the first heating after film formation in order to adjust the crystallinity of CuMO2.

[0062] Method (3) The substrate was placed in the chamber of a magnetron sputtering device containing a copper target and a target made of M, a metal other than copper, and 5.0 × 10 -4 The chamber is evacuated to a vacuum of less than Pa. Thereafter, the substrate is heated to 200 to 500° C. and maintained at that temperature.

[0063] After heating, the pressure inside the chamber increases, so evacuation is continued until the pressure inside the chamber reaches 5.0 x 10 -4 Evacuate to a pressure of less than 1 Pa.

[0064] After heating and evacuation, argon gas and oxygen gas are introduced, a pulsed DC voltage is applied to the target to generate plasma, and a copper oxide compound is produced on the substrate by magnetron sputtering. The power applied to each target is adjusted to obtain the desired composition. The voltage applied here may be DC, RF, or AC (bipolar alternating current). The target material may be copper oxide.

[0065] Argon gas and oxygen gas are then introduced, and a pulsed DC voltage is applied to the target to generate plasma. The voltage applied here may be DC, RF, or AC (bipolar alternating current). The target material may be copper oxide or oxide of M. If the target material has high electrical resistance, RF is selected as the power source. Furthermore, the sample may be removed and reheated after film formation to adjust the crystallinity of CuMO2.

[0066] Method (4) The substrate was placed in the chamber of a magnetron sputtering device containing a copper target and a target made of M, a metal other than copper, and 5.0 × 10 -4 The chamber is evacuated to a vacuum of 0.1 Pa or less. Argon gas and oxygen gas are then introduced, a pulsed DC voltage is applied to the target to generate plasma, and a copper oxide compound is produced on the substrate by magnetron sputtering. The power applied to each target is adjusted to obtain the desired composition. The voltage applied here may be DC, RF, or AC (bipolar alternating current). The target material may be copper oxide or an oxide of M. If the target material has high electrical resistance, an RF power source is selected.

[0067] After film formation, the substrate is removed from the chamber and heated at atmospheric pressure at 200 to 500°C for 5 to 120 minutes. Furthermore, the sample may be removed and reheated under conditions different from the first heating after film formation in order to adjust the crystallinity of CuMO2.

[0068] If the thickness of the thin film is too thick, there are drawbacks such as cracks occurring in the film, interference fringes appearing, and scratches becoming noticeable, while if the thickness is too thin, the desired antiviral performance may not be exhibited.Taking economical considerations into account, the thickness of the thin film is preferably 10 to 5000 nm, and particularly preferably 100 to 3000 nm.

[0069] <Antiviral coating> The antiviral material of the present invention can also be obtained as a film-attached substrate by applying a coating material containing particles of the antiviral material of the present invention to the surface of a substrate to form a coating film on the substrate. The coating film containing the antiviral material of the present invention has high antiviral properties.

[0070] The coating film is obtained as a coated body in which the substrate and the coating film are integrated by forming a film containing the antiviral compound of the present invention on a substrate.

[0071] Examples of methods for forming a coating film on a substrate include wet coating methods.

[0072] (Wet coating method) In the wet coating method, a coating material containing particles made of an antiviral material is applied to the surface of a substrate, and a film-coated substrate is obtained in which a coating film is formed on the substrate. Examples of wet coating methods include spin coating, wipe coating, spray coating, squeegee coating, casting, die coating, inkjet coating, flow coating, roll coating, dip coating, gravure coating, brush coating, hand coating, and curtain flow coating.

[0073] The coating material for forming the coating film of the present invention contains particles of the antiviral material of the present invention made of a Cu-MO compound or Cu-M-M'-O compound (hereinafter referred to as antiviral material particles), a binder, and a liquid medium. If necessary, the coating material may contain a dispersant for dispersing the antiviral material particles. The coating film is formed by applying a paint to the surface of a substrate to form a wet film, and then removing the liquid medium, and is composed of antiviral material particles and a binder.

[0074] The average particle size of the antiviral material particles used to form the coating film can vary depending on the purpose, but for transparent applications, a particle size of 5 to 100 nm is preferred to ensure transparency, and a particle size of 40 to 70 nm is more preferred. If the average particle size is too small, the antiviral material particles will be embedded in the formed film, making it difficult to achieve antiviral effects. If the average particle size is too large, the mechanical strength of the formed coating film will be insufficient, and transparency may not be ensured. The average particle size can be measured by measuring the aggregate particle size of fine particles in the paint using light scattering and a particle size distribution analyzer (for example, "Microtrac UPA particle size distribution analyzer" manufactured by Honeywell).

[0075] The content of antiviral material particles in the paint is preferably 0.01 to 20% by mass, and more preferably 0.3 to 10% by mass, relative to 100% by mass of the paint. When the content of antiviral material particles in the paint is 0.01% by mass or more, the antiviral properties of the coating film are fully exhibited and this effect can be maintained for a long period of time. When the content is 20% by mass or less, the dispersion state of the antiviral material particles can be maintained in an appropriate manner, and a coating film that maintains transparency can be formed on the surface of the substrate.

[0076] The binder is used to support the antiviral material particles of the present invention. The binder functions to bond the wet film to the substrate during film formation and to disperse and bind other components in the coating film.

[0077] Examples of binders include metal oxide precursors and fluorine-based resins, and can be appropriately selected depending on the printing method, coating method, etc. Examples of metal oxide precursors include precursors of metal oxides such as Si, Al, Ti, Ta, Zr, and Sn. Among these, it is preferable to use an inorganic binder such as a precursor of a metal oxide of Si because of its excellent durability.

[0078] The binder content in the paint is preferably 0.0025 to 30% by mass, and more preferably 0.01 to 10% by mass, relative to 100% by mass of the paint. A binder content of 0.0025% by mass or more ensures good adhesion to the substrate, while a binder content of 0.01% by mass or more enhances adhesion to the substrate. Furthermore, a binder content of 30% by mass or less allows the surfaces of the antiviral material particles to be exposed on the coating film surface, enabling the antiviral material particles to come into contact with viruses, allowing a coating film to be appropriately formed on the substrate surface in a state in which the antiviral effect can be exerted.

[0079] Examples of the liquid medium include water and water-soluble organic solvents. Examples of the water-soluble organic solvent include hydrocarbon organic solvents, such as alcohol organic solvents, ketone organic solvents, ether organic solvents, and ester organic solvents.

[0080] The content of the liquid medium in the paint is preferably 50 to 99.98% by mass, and more preferably 80 to 99.9% by mass, relative to 100% by mass of the paint. If the content of the liquid medium is 50% by mass or more, the rapid progress of hydrolysis and condensation reactions can be prevented, and if it is 99.98% by mass or less, the hydrolysis and condensation reactions can be sufficiently progressed during coating film formation.

[0081] A dispersant may be used to uniformly disperse antiviral material particles in the paint. Examples of dispersants include fatty acid amides, ester salts of acidic polyamides, acrylic resins, oxidized polyolefins, and other polymers that have affinity for inorganic pigments. Commercially available dispersants may be used, and examples of commercially available products include the "Disparlon" series (product name, manufactured by Kusumoto Chemicals Co., Ltd.) and the "DISPERBYK" series (product name, manufactured by BYK-Chemie Co., Ltd.).

[0082] The content of the dispersant in the paint is preferably 0.001 to 10% by mass, and more preferably 0.003 to 6% by mass, relative to 100% by mass of the paint. A dispersant content of 0.01% by mass or more can exert a dispersing effect on the antiviral material particles and produce a coating film that maintains transparency, while a dispersant content of 10% by mass or less can maintain the dispersing effect and produce a coating film that maintains antiviral properties and has high mechanical strength.

[0083] The substrate may be the same as those described above, and the preferred substrates are also the same.

[0084] Below, we will explain a method for forming a coating film (antiviral film) using Cu-MO compound particles as the antiviral material particles and a Si metal oxide precursor as the binder. The same method applies when Cu-M-M'-O compound particles are used.

[0085] First, the coating material is applied to the surface of the substrate by wet coating to form a wet film, which may be applied to one or both surfaces of the substrate.

[0086] As precursors of metal oxides of Si to be used in coating materials, silicic acid, partial condensates of silicic acid, alkali metal silicates, silane compounds having a hydrolyzable group bonded to a silicon atom, and partial hydrolyzed condensates of the silane compounds can be used. Specifically, it may be silicic acid prepared by desalting water glass, or a sol-gel silica precursor. In the case of desalted silicic acid, the antiviral effect can be enhanced due to the presence of many hydrophilic groups. In the case of sol-gel silica precursor, it does not have the effect of oxidizing monovalent copper ions, so it is expected that the antiviral effect will be maintained for a long period of time and is therefore suitable for supporting particles. If a binder with an oxidizing effect is used, the monovalent copper will be oxidized, making it impossible to maintain the antiviral effect for a long period of time.

[0087] A coating material containing particles of a Cu-MO compound, a precursor of a metal oxide of Si, and a water-soluble organic solvent as a liquid medium is applied to the surface of a substrate to form a wet film, and then the solvent in the wet film is removed and the precursor of the metal oxide of Si is condensed to form a metal oxide layer of Si.

[0088] Conditions for removing the solvent from the wet film and condensing the Si metal oxide precursor include, for example, heating the wet film at a temperature in the range of 50 to 300°C for 5 to 30 minutes. This causes dehydration condensation between silanol groups in the Si metal oxide precursor and between OH groups on the surface of the antiviral material particles and the silanol groups in the precursor, resulting in condensation of the Si metal oxide precursor, forming a strongly bonded Si metal oxide layer. The Si metal oxide layer after condensation may contain unreacted silanol groups.

[0089] After the coating is applied, it is preferable to carry out a post-treatment for the purpose of removing the medium or increasing the hardness of the film. Examples of the post-treatment include drying or heating at room temperature, irradiation with electromagnetic waves such as ultraviolet rays or electron beams, and heating. Taking into account the heat resistance of the substrate, heating is preferably carried out at a temperature of 50 to 700°C, particularly 100 to 350°C, for 5 to 60 minutes. In particular, when the substrate is made of a material with low heat resistance such as an organic resin, or when low-molecular-weight compounds in the substrate diffuse out of the substrate due to heating, it is preferable to carry out the post-treatment by irradiation with electromagnetic waves such as ultraviolet rays or electron beams.

[0090] The content of antiviral material particles in the coating film may be any amount that allows the desired antiviral properties to be obtained when incorporated into the Si metal oxide layer. Specifically, a content of antiviral material particles of 40 to 80 mass% relative to the total mass of the coating film is preferred because the surfaces of the antiviral material particles can be exposed on the coating film surface, enabling the antiviral material particles to come into contact with viruses. If the content is more than 80 mass%, the mechanical strength of the coating film may be poor, and the antiviral properties may not be sustained. If the content is less than 40 mass%, the antiviral material particles may be buried in the formed coating film, potentially preventing the antiviral effect from being achieved.

[0091] In the present invention, the coating film preferably has one or more metal atoms selected from the group consisting of Cu, Si, and M located on the surface of the film. By forming the coating film with some of the metal atoms exposed on the surface of the film, the efficiency of contact of the coating film with viruses increases, and excellent antiviral properties can be exhibited. The metal atoms are preferably contained within a range of 1 to 50 nm in thickness from the surface of the coating film, and by containing the metal atoms within this range, efficient contact between viruses and the substrate surface can be achieved, thereby exhibiting antiviral effects.

[0092] The average surface roughness Ra of the coating film of the present invention is preferably 1 nm or more and 50 nm or less, which allows efficient contact between the coating film surface and viruses, thereby enabling the coating film to exhibit high antiviral properties.

[0093] In the present invention, the thickness of the resulting film can be controlled by adjusting the concentration of the coating material, the type of solvent, the application conditions, the post-treatment conditions, etc. The coating film of the present invention can be produced to various thicknesses depending on the purpose. If the film is too thick, there are drawbacks such as cracks in the film, interference fringes, and scratches that become noticeable, while if the film is too thin, the desired antiviral performance may not be exhibited. Taking economical efficiency into consideration, the thickness of the coating film is preferably 10 nm to 5 μm, and particularly preferably 10 nm to 2 μm.

[0094] Another film may be provided between the substrate and the coating film. An example of the another film is an ion diffusion barrier layer (a layer intended to prevent metal ions from diffusing into the glass when the substrate is glass). By providing the ion diffusion barrier layer, the diffusion of metal ions into the glass can be suppressed, and the antiviral effect can be maintained for a long period of time.

[0095] The fluorine-based resins that can be used as binders will be described below.

[0096] The fluororesin used in the paint for antiviral material coating of the present invention is a resin containing a fluorine-containing polymer containing units based on fluoroolefin (hereinafter also referred to as units F) or a cured product thereof. Fluoroolefins are olefins in which one or more hydrogen atoms have been substituted with fluorine atoms. In fluoroolefins, one or more hydrogen atoms not substituted with fluorine atoms may be substituted with chlorine atoms.

[0097] Specific examples of fluoroolefins include CF2=CF2, CF2=CFCl, CF2=CHF, CH2=CF2, CF2=CFCF3, CF2=CHCF3, CF3CH=CHF, CF3CF=CH2, and CH2=CX. f1 (CF2) n1 Y f1 (In the formula, X f1 and Y f1 are independently a hydrogen atom or a fluorine atom, and n1 is an integer of 2 to 10. As the fluoroolefin, CF2=CF2, CH2=CF2, CF2=CFCl, CF3CH=CHF, and CF3CF=CH2 are preferred, with CF2=CFCl being particularly preferred, in view of excellent weather resistance of the coated body. Two or more types of fluoroolefins may be used in combination.

[0098] The fluorine-containing polymer may be one containing only units F (fluorine-containing polymer (1)), one containing units F and units based on a monomer containing a fluorine atom other than a fluoroolefin (fluorine-containing polymer (2)), or one containing units F and units based on a monomer not containing a fluorine atom (fluorine-containing polymer (3)).

[0099] Examples of the fluorine-containing polymer containing only the unit F (fluorine-containing polymer (1)) include a homopolymer of a fluoroolefin and a copolymer of two or more kinds of fluoroolefins, and specific examples thereof include polytetrafluoroethylene, polychlorotrifluoroethylene, a tetrafluoroethylene-hexafluoropropylene copolymer, and polyvinylidene fluoride.

[0100] Examples of the fluorine-containing polymer containing units F and units based on a monomer containing a fluorine atom other than a fluoroolefin (fluorine-containing polymer (2)) include fluoroolefin-perfluoro(alkyl vinyl ether) copolymers, and specific examples include tetrafluoroethylene-perfluoro(alkyl vinyl ether) copolymers.

[0101] Here, the content of units F in the fluorine-containing polymer is preferably 20 to 100 mol %, more preferably 30 to 80 mol %, and particularly preferably 40 to 60 mol %, based on all units contained in the fluorine-containing polymer, from the viewpoint of weather resistance of the coated body.

[0102] The fluorine-containing polymer preferably contains units based on fluoroolefin (units F) and units based on a monomer not containing a fluorine atom, since this makes it easier to adjust the transmittance and reflectance of each light ray at each wavelength of the coating film. Examples of units based on a monomer not containing a fluorine atom include units having a crosslinkable group and units not containing a crosslinkable group.

[0103] Examples of the fluorine-containing polymer containing units F and units based on a monomer not containing a fluorine atom (fluorine-containing polymer (3)) include chlorotrifluoroethylene-vinyl ether copolymer, chlorotrifluoroethylene-vinyl ether-vinyl ester copolymer, chlorotrifluoroethylene-vinyl ester-allyl ether copolymer, tetrafluoroethylene-vinyl ester copolymer, tetrafluoroethylene-vinyl ester-allyl ether copolymer, ethylene-tetrafluoroethylene copolymer, etc., and from the viewpoint of adjusting the transmittance and refractive index of the coating film, chlorotrifluoroethylene-vinyl ether copolymer is preferred.

[0104] From the viewpoint of durability, the fluorine-containing polymer (3) preferably contains a unit having a crosslinkable group (hereinafter also referred to as unit (1)) as a unit based on a monomer not containing a fluorine atom. The unit (1) may be a unit based on a monomer having a crosslinkable group (hereinafter also referred to as monomer (1)), or may be a unit obtained by converting the crosslinkable group of a fluorine-containing polymer containing unit (1) into a different crosslinkable group. Examples of such units include units obtained by reacting a fluorine-containing polymer containing a unit having a hydroxy group with a polycarboxylic acid or an acid anhydride thereof to convert some or all of the hydroxy groups into carboxy groups. Specific examples of the crosslinkable group include a hydroxy group, a carboxy group, an amino group, an epoxy group, and a hydrolyzable silyl group, and the hydroxy group and the carboxy group are preferred in terms of further improving the strength of the film.

[0105] The crosslinkable group of the unit (1) may be crosslinked in the film by a curing agent described later, or may remain uncrosslinked. The fluorine-containing polymer in the film is preferably crosslinked by reaction with a curing agent. When the crosslinkable group of the unit (1) is crosslinked by a curing agent, the durability of the film is more excellent. When the crosslinkable group of the unit (1) remains uncrosslinked, the dispersibility of the inorganic pigment in the film is more excellent.

[0106] Examples of the monomer (1) having a carboxy group include unsaturated carboxylic acids, (meth)acrylic acids, and monomers obtained by reacting the hydroxy group of the above-mentioned monomers having a hydroxy group with a carboxylic acid anhydride. 11 -Y 11 The monomer represented by the formula (11) is preferred. The symbols in the formula have the following meanings: X 11 is CH2=CH-, CH(CH3)=CH- or CH2=C(CH3)-, preferably CH2=CH- or CH(CH3)=CH-. Y 11 is a carboxy group or a monovalent saturated hydrocarbon group having a carboxy group and having 1 to 12 carbon atoms, and is preferably a carboxy group or a carboxyalkyl group having 1 to 10 carbon atoms.

[0107] Examples of the monomer (1) having a hydroxy group include vinyl ethers, vinyl esters, allyl ethers, allyl esters, (meth)acrylic acid esters, and allyl alcohols, each of which has a hydroxy group. 12 -Y 12 Preferred is a monomer represented by the formula (12) or allyl alcohol. 12 is CH2=CHO-, CH2=CHCH2O-, CH2=CHCOO- or CH2=C(CH3)COO-. Y 12 is a monovalent saturated hydrocarbon group having 2 to 12 carbon atoms and having a hydroxy group. The monovalent saturated hydrocarbon group may be linear or branched. Furthermore, the monovalent saturated hydrocarbon group may be formed of a ring structure or may contain a ring structure. The monovalent saturated hydrocarbon group is preferably an alkyl group having 2 to 6 carbon atoms or an alkyl group containing a cycloalkylene group having 6 to 8 carbon atoms.

[0108] Specific examples of the monomer (11) include CH2=CHCOOH, CH(CH3)=CHCOOH, CH2=C(CH3)COOH, and CH2=CH(CH2) n2 Examples of the compound include compounds represented by COOH (where n2 represents an integer of 1 to 10).

[0109] Specific examples of the monomer (12) include CH2=CHO-CH2-cycloCH 10 -CH2OH, CH2=CHCH2O-CH2-cycloC6H 10 -CH2OH, CH2=CHOCH2CH2OH, CH2=CHCH2OCH2CH2OH, CH2=CHOCH2CH2CH2CH2OH, CH2=CHCH2OCH2CH2CH2CH2OH, CH2=CHCOOCH2CH2OH, CH2=C(CH3)COOCH2CH2OH. 10 "-" represents a cyclohexylene group, and "-cycloCH 10 The binding site of - is usually 1,4-.

[0110] Two or more types of monomer (1) may be used in combination, and the monomer (1) may have two or more types of crosslinkable groups.

[0111] The content of the units (1) is preferably from 0.5 to 35 mol %, more preferably from 3 to 25 mol %, still more preferably from 5 to 25 mol %, particularly preferably from 5 to 20 mol %, based on all units contained in the fluorine-containing polymer (3).

[0112] The fluorine-containing polymer (3) preferably has a crosslinked structure from the viewpoint of improving the strength of the coating film. Specifically, when the fluorine-containing polymer (3) contains units (1), it is preferred that the crosslinkable groups of the units (1) are crosslinked by a curing agent or the like described below to form a crosslinked structure. That is, the fluorine-containing polymer (3) in this specification may include both a state in which the crosslinkable groups remain and a state in which the crosslinkable groups are crosslinked by a curing agent or the like.

[0113] The fluorine-containing polymer (3) preferably further contains, as a unit based on a monomer not containing a fluorine atom, a unit based on a monomer not containing a crosslinkable group (hereinafter also referred to as monomer (2)) (hereinafter also referred to as unit (2)). As the unit based on a monomer not containing a crosslinkable group, a unit based on one or more monomers selected from the group consisting of vinyl ether, vinyl ester, allyl ether, allyl ester, and (meth)acrylic acid ester is preferred.

[0114] Unit (2) is X 2 -Y 2 Preferred are units based on a monomer represented by the following formula: X 2 is CH2=CHC(O)O-, CH2=C(CH3)C(O)O-, CH2=CHOC(O)-, CH2=CHCH2OC(O)-, CH2=CHO-, or CH2=CHCHO-, and CH2=CHOC(O)-, CH2=CHCH2OC(O)-, CH2=CHO-, or CH2=CHCHO- is preferred in terms of excellent weather resistance of the antiviral material. Y 2is a monovalent hydrocarbon group having 1 to 24 carbon atoms. The monovalent hydrocarbon group may be linear or branched. The monovalent hydrocarbon group may be composed of a ring structure or may contain a ring structure. The monovalent hydrocarbon group may be a monovalent saturated hydrocarbon group or a monovalent unsaturated hydrocarbon group.

[0115] The monovalent hydrocarbon group is preferably an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group, and particularly preferably an alkyl group having 2 to 12 carbon atoms, a cycloalkyl group having 6 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms. Specific examples of the alkyl group include a methyl group, an ethyl group, a tert-butyl group, a hexyl group, a nonyl group, a decyl group, and a dodecyl group. Specific examples of the cycloalkyl group include a cyclohexyl group. Specific examples of the aralkyl group include a benzyl group. Specific examples of the aryl group include a phenyl group and a naphthyl group. The hydrogen atoms of the cycloalkyl group, aryl group, or aralkyl group may be substituted with an alkyl group. In this case, the number of carbon atoms of the alkyl group as a substituent is not included in the number of carbon atoms of the cycloalkyl group or aryl group.

[0116] Two or more types of monomer (2) may be used in combination. Specific examples of the monomer (2) include ethyl vinyl ether, tert-butyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether, vinyl acetate, vinyl pivalate, vinyl neononanoate (manufactured by HEXION, trade name "Veova 9"), vinyl neodecanoate (manufactured by HEXION, trade name "Veova 10"), vinyl benzoate, vinyl tert-butyl benzoate, tert-butyl (meth)acrylate, and benzyl (meth)acrylate.

[0117] The content of the units (2) is preferably from 5 to 60 mol %, particularly preferably from 10 to 50 mol %, based on all units contained in the fluorine-containing polymer (3).

[0118] As the fluorine-containing polymer (3), commercially available products may be used, and specific examples include the "Lumiflon" series (trade name of AGC), the "Kynar" series (trade name of Arkema), the "Zeffle" series (trade name of Daikin Industries, Ltd.), the "Eterflon" series (trade name of Eterflon), and the "Zendura" series (trade name of Honeywell).

[0119] The content of the fluorine-containing polymer in the coating film is preferably from 5 to 95 mass %, particularly preferably from 10 to 90 mass %, based on the total mass of the coating film, from the viewpoint of weather resistance.

[0120] From the viewpoint of coating film adhesion to the substrate, the content of fluorine atoms in the coating film is preferably 65% ​​by mass or less, more preferably 50% by mass or less, even more preferably 40% by mass or less, particularly preferably 25% by mass or less, and most preferably 20% by mass or less.

[0121] The coating film may have a crosslinked structure between a fluorine-containing polymer containing units F and units (1) and a compound (hereinafter also referred to as a curing agent) having two or more groups in one molecule of at least one type selected from the group consisting of an isocyanate group, a blocked isocyanate group, an epoxy group, a carbodiimide group, an oxazoline group, a β-hydroxyalkylamide group, a hydrolyzable silyl group and a silanol group. In this case, the coating film contains a cured product of the fluorine-containing polymer. When the coating film has the above-mentioned crosslinked structure, specifically, when the crosslinkable groups of the units (1) contained in the fluorine-containing polymer are crosslinked by a curing agent, the coating film has excellent hardness and durability.

[0122] The coating film may have a crosslinked structure formed by reaction of two or more selected from the group consisting of a crosslinkable group of a fluorine-containing polymer contained in the coating film, a curing agent contained in the film, and a substrate (for example, a reactive group such as a silanol group present on the surface of a glass plate). For example, when a film containing a curing agent having one or more groups selected from hydrolyzable silyl groups and silanol groups is formed on a glass plate containing silicon oxide, the hydrolyzable silyl groups of the curing agent (specifically, silanol groups generated by hydrolysis) react with the silanol groups present on the surface of the glass plate to form a crosslinked structure, which results in better adhesion of the coating film to the glass plate.

[0123] Furthermore, when a coating film containing a fluorine-containing polymer having hydrolyzable silyl groups as crosslinkable groups is formed on a glass plate containing silicon oxide, the hydrolyzable silyl groups of the fluorine-containing polymer (specifically, silanol groups generated by hydrolysis) react with the silanol groups present on the surface of the glass plate to form a crosslinked structure. Therefore, the adhesion of the coating film to the glass plate, the hardness of the coating film, and the durability of the coating film are superior.

[0124] When the fluorine-containing polymer has a hydroxy group, the curing agent is preferably a compound having two or more isocyanate groups or blocked isocyanate groups per molecule. When the fluorine-containing polymer has a carboxy group, the curing agent is preferably a compound having two or more epoxy groups, carbodiimide groups, oxazoline groups or β-hydroxyalkylamide groups per molecule. When the fluorine-containing polymer has both a hydroxy group and a carboxy group, it is preferable to use a compound having two or more isocyanate groups or blocked isocyanate groups per molecule in combination with a compound having two or more epoxy groups, carbodiimide groups, oxazoline groups or β-hydroxyalkylamide groups per molecule.

[0125] In order to further improve the adhesion between the coating film of the present invention and a glass plate, the coating film preferably contains a curing agent having one or more groups selected from a hydrolyzable silyl group and a silanol group. The compound having two or more isocyanate groups in one molecule is preferably a polyisocyanate monomer or a polyisocyanate derivative. The polyisocyanate monomer is preferably an alicyclic polyisocyanate, an aliphatic polyisocyanate, or an aromatic polyisocyanate. The polyisocyanate derivative is preferably a polymer or modified product (biuret, isocyanurate or adduct) of a polyisocyanate monomer.

[0126] Specific examples of aliphatic polyisocyanates include tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethyl-1,6-diisocyanatohexane, and aliphatic diisocyanates such as lysine diisocyanate, lysine triisocyanate, 4-isocyanatomethyl-1,8-octamethylene diisocyanate, and bis(2-isocyanatoethyl) 2-isocyanatoglutarate. Specific examples of the alicyclic polyisocyanate include alicyclic diisocyanates such as isophorone diisocyanate, 1,3-bis(isocyanatomethyl)-cyclohexane, 4,4'-dicyclohexylmethane diisocyanate, norbornene diisocyanate, and hydrogenated xylylene diisocyanate. Specific examples of aromatic polyisocyanates include aromatic diisocyanates such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, naphthalene diisocyanate, xylylene diisocyanate, etc. The compound having two or more blocked isocyanate groups in one molecule is preferably a compound in which two or more isocyanate groups in the above-mentioned polyisocyanate monomer or polyisocyanate derivative are blocked with a blocking agent.

[0127] The blocking agent is a compound having active hydrogen, and specific examples thereof include alcohols, phenols, active methylenes, amines, imines, acid amides, lactams, oximes, pyrazoles, imidazoles, imidazolines, pyrimidines, and guanidines.

[0128] Specific examples of compounds having two or more epoxy groups in one molecule include bisphenol-type epoxy compounds (A-type, F-type, S-type, etc.), diphenyl ether-type epoxy compounds, hydroquinone-type epoxy compounds, naphthalene-type epoxy compounds, biphenyl-type epoxy compounds, fluorene-type epoxy compounds, hydrogenated bisphenol A-type epoxy compounds, bisphenol A nucleus-containing polyol-type epoxy compounds, polypropylene glycol-type epoxy compounds, glycidyl ester-type epoxy compounds, glycidyl amine-type epoxy compounds, glyoxal-type epoxy compounds, alicyclic epoxy compounds, alicyclic polyfunctional epoxy compounds, and heterocyclic epoxy compounds (triglycidyl isocyanurate, etc.).

[0129] Specific examples of compounds having two or more carbodiimide groups in one molecule include alicyclic carbodiimides, aliphatic carbodiimides, aromatic carbodiimides, and polymers and modified products thereof.

[0130] Specific examples of compounds having two or more oxazoline groups in one molecule include addition-polymerizable oxazolines having 2-oxazoline groups and polymers of such addition-polymerizable oxazolines.

[0131] Specific examples of compounds having two or more β-hydroxyalkylamide groups in one molecule include N,N,N',N'-tetrakis-(2-hydroxyethyl)-adipamide (Primid XL-552, manufactured by EMS) and N,N,N',N'-tetrakis-(2-hydroxypropyl)-adipamide (Primid QM 1260, manufactured by EMS).

[0132] As the curing agent having at least one group selected from the group consisting of a hydrolyzable silyl group and a silanol group, SiZ a R 4-a and a partial hydrolysis condensate thereof. In the formula, R represents a monovalent hydrocarbon group having 1 to 10 carbon atoms, Z represents an alkoxy group or a hydroxy group having 1 to 10 carbon atoms, and a represents an integer of 1 to 4.

[0133] R is a monovalent hydrocarbon group having 1 to 10 carbon atoms. The monovalent hydrocarbon group may have a substituent (for example, a fluorine atom). That is, some or all of the hydrogen atoms of the monovalent hydrocarbon group may be substituted with a substituent. R is preferably a methyl group, a hexyl group, a decyl group, a phenyl group, a trifluoropropyl group, or the like. When multiple Rs are present in one molecule, the multiple Rs may be the same or different, and are preferably the same. Z is an alkoxy group or hydroxy group having 1 to 10 carbon atoms, preferably an alkoxy group. When Z is an alkoxy group, it is preferably a methoxy group or an ethoxy group. When there are multiple Zs in one molecule, they may be the same or different, and it is preferable that they are the same. a is an integer of 1 to 4, preferably 2 to 4.

[0134] SiZ a R 4-a Specific examples of the compound represented by the formula (I) include tetrafunctional alkoxysilanes (tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, etc.), trifunctional alkoxysilanes (methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, decyltrimethoxysilane, trifluoropropyltrimethoxysilane, etc.), and bifunctional alkoxysilanes (dimethyldimethoxysilane, diphenyldimethoxysilane, dimethyldiethoxysilane, diphenyldiethoxysilane, etc.), of which tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, and phenyltrimethoxysilane are preferred.

[0135] The coating material may contain a non-fluorine resin. Specific examples of the non-fluorine resin include alkyd resin, aminoalkyd resin, polyester resin, epoxy resin, urethane resin, epoxy polyester resin, vinyl acetate resin, acrylic resin, vinyl chloride resin, phenol resin, modified polyester resin, acrylic silicone resin, and silicone resin. When the non-fluorine resin among these specific examples is a curable resin, the non-fluorine resin contained in the film is usually a cured resin.

[0136] The coating film is preferably formed using a paint containing a fluorine-containing polymer, and the paint is preferably a liquid paint.

[0137] When the fluorine-containing polymer in the coating material is a fluorine-containing polymer containing a carboxy group, the acid value of the fluorine-containing polymer in the coating material is preferably from 1 to 200 mgKOH / g, more preferably from 1 to 150 mgKOH / g, further preferably from 3 to 100 mgKOH / g, and particularly preferably from 5 to 50 mgKOH / g, from the viewpoint of the strength of the coating film.

[0138] When the fluorine-containing polymer in the coating material is a fluorine-containing polymer containing a hydroxy group, the hydroxyl value of the fluorine-containing polymer in the coating material is preferably from 1 to 200 mgKOH / g, more preferably from 1 to 150 mgKOH / g, still more preferably from 3 to 100 mgKOH / g, and particularly preferably from 10 to 60 mgKOH / g, from the viewpoint of film strength.

[0139] The fluorine-containing polymer in the coating material may have either an acid value or a hydroxyl value, or may have both.

[0140] The content of the fluorine-containing polymer in the coating material is preferably from 5 to 90 mass %, particularly preferably from 10 to 80 mass %, based on the total mass of the solid content contained in the coating material, from the viewpoint of weather resistance of the coated body.

[0141] The content of the fluorine-containing polymer in the solid content of the paint is preferably from 10 to 90 mass %, particularly preferably from 40 to 70 mass %, based on the total mass of the solid content of the paint.

[0142] The coating material may contain a curing agent that forms a crosslinked structure in the film.

[0143] When the fluorine-containing polymer in the coating material contains a crosslinkable group, the crosslinkable group of the fluorine-containing polymer in the coating material is reacted with a curing agent to crosslink the fluorine-containing polymer, thereby curing the coating film. In this case, a coating film having a crosslinked structure between the fluorine-containing polymer and the curing agent is formed.

[0144] Furthermore, when the curing agent in the coating material has one or more types selected from a hydrolyzable silyl group and a silanol group, a film having a crosslinked structure of the curing agent, the glass plate, and, if necessary, the fluorine-containing polymer is formed by reacting the curing agent with a glass plate containing silicon oxide and, if necessary, the fluorine-containing polymer.

[0145] When the coating material contains a curing agent, the content of the curing agent is preferably from 5 to 200 parts by mass, particularly preferably from 10 to 150 parts by mass, per 100 parts by mass of the fluorine-containing polymer in the coating material.

[0146] Furthermore, when the coating material contains an inorganic pigment as inorganic particles, it is preferable to contain a dispersant. When the coating material contains a dispersant, the pigment is less likely to aggregate, making it easier to obtain the desired optical properties. Examples of dispersants include those mentioned above.

[0147] The coating material preferably contains a liquid medium. Examples of the liquid medium include water and organic solvents, with organic solvents being preferred. When the coating material contains an organic solvent, the coating material is preferably a solvent-based coating material containing a fluorine-containing polymer and an organic solvent, with the fluorine-containing polymer dissolved in the organic solvent. In this case, it is easy to improve the adhesion between the substrate (specifically, a glass plate) and the coating film, or between the primer layer applied to the substrate and the coating film.

[0148] Examples of organic solvents include petroleum-based mixed solvents (toluene, xylene, ExxonMobil's Solvesso 100, ExxonMobil's Solvesso 150, etc.), aromatic hydrocarbon solvents (mineral spirits, etc.), ester solvents (ethyl acetate, butyl acetate, etc.), ketone solvents (methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), alcohol solvents (ethanol, tert-butyl alcohol, isopropyl alcohol, etc.), etc. Two or more organic solvents may be used in combination.

[0149] The antiviral material of the present invention has high antiviral properties and can be used as an antiviral material. Specifically, the antiviral material of the present invention can be applied to various products such as goggles, face shields, protective clothing, panel boards, paints for painting, and touch panel coating solutions, and can reduce contact infection with viruses.

[0150] The antiviral material of the present invention exhibits a good inactivation effect against viruses such as animal viruses, insect viruses, plant viruses, bacterial viruses (bacteriophages or phages), etc. Examples of animal viruses include influenza viruses, coronaviruses, noroviruses, rotaviruses, retroviruses, avian influenza viruses, hog cholera viruses, adenoviruses, respiratory syncytial viruses, herpes viruses, measles viruses, rubella viruses, AIDS viruses (HIV), baculoviruses, entomopox viruses, and cypoviruses. [Example]

[0151] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these. In the following description, the same components are used. Unless otherwise specified, "parts" and "%" represent "parts by mass" and "% by mass." Examples 1, 3, and 4 are working examples, and Examples 2 and 5 are comparative examples.

[0152] <Test Example 1> (Example 1) The paint was applied to the surface of the glass substrate to form a wet film, and then the liquid medium was removed to form a coating film of the antiviral material. The dispersant used for the particle dispersion was "DISPERBYK-190" (trade name) manufactured by BYK-Chemie, and the solvent was "Solmix AP-1" (trade name) manufactured by Japan Alcohol Sales Co., Ltd. Tetraethoxysilane (TEOS) and 3-glycidoxypropyltrimethoxysilane (GPTMS) were used as precursors for the Si metal oxide used in the paint.

[0153] 1. Preparation of Particle Dispersion 5.71 g of CuAlO2 antiviral particles (average particle size 50 nm) prepared by the sol-gel method described above and 4.29 g of DISPERBYK-190 were added to 18.57 g of AP-1 solvent and stirred. 100 g of zirconia beads with a diameter of 0.3 mm were then added and stirred for approximately 6 hours using a paint shaker. The zirconia beads were then removed by filtration, leaving a particle dispersion.

[0154] 2. Preparation of the base liquid To 27.19 g of AP-1 solvent, 17.23 g of TEOS, 6.15 g of GPTMS, and 0.33 g of BYK-307 (trade name) as a surface conditioner were added, followed by 7.20 g of acetic acid and 21.90 g of water, and the mixture was thoroughly stirred. The mixture was heated to 50°C and held for 2 hours to promote the reaction, and then cooled to room temperature to form the base solution. The pH of the base solution was 2.8.

[0155] 3. Preparation of Paint To 1.875 g of AP-1 solvent, 3.125 g of the particle dispersion liquid (solid content 20% by mass) and 5 g of the main liquid (solid content 12.5% ​​by mass) were added to obtain a coating material.

[0156] 4. Coating The coating material was applied to an AGC float glass substrate (thickness: 2 mm) using a spin coater so that the dried film thickness would be 1.7 μm. The substrate was then heated in a drying oven set at 200°C for 30 minutes to obtain a glass substrate having an antiviral coating film laminated on the glass substrate.

[0157] (Example 2) For comparison with the glass substrate with an antiviral coating, and to calculate the antiviral activity value described below, an unprocessed float glass substrate (2 mm thick) manufactured by AGC that was not coated with an antiviral coating was prepared.

[0158] (Antiviral evaluation) The glass of Example 1 and the glass substrate of Example 2 were subjected to an antiviral property evaluation test. Bacteriophage Φ6 was used as the virus in the antiviral evaluation test. This is a type of virus that infects P. syringae, and is a phage that is not subject to the JIS standard for photocatalysts. Although it does not infect the human body, it is structurally enveloped and is therefore used as a substitute for the influenza virus.

[0159] The evaluation test standard was ISO21702 (2019) and the evaluation was carried out under the following conditions. The size of the test piece (glass in Example 1 or glass substrate in Example 2) used in the evaluation test was 50 mm x 50 mm. The test phage used was bacteriophage Φ6 (host Pseudomonas syringae (NBRC14084)). Sterilization treatment before the test was performed by wiping with absolute ethanol. The evaluation environment was a dark place, and the reaction conditions were an action temperature of 25°C and an action time of 1 hour, 6 hours, and 24 hours. The test method was as follows. 1) The surface of the test piece was wiped clean with absolute ethanol. 2) Inject virus solution (1 x 10 of bacteriophage Φ6) into the test piece. 7 PFU / ml) was dropped onto the sample, and the sample was covered with a 40 mm x 40 mm polypropylene film ("VF-10" (trade name) manufactured by Kokuyo Co., Ltd.) to obtain a test sample. 3) The test specimen was left standing at 25°C for a predetermined period of time (1 hour, 6 hours, and 24 hours). 4) After leaving it to stand, the virus on the test specimen was washed away with 10 mL of SCDLP medium, and the test specimen was recovered, after which the number of plaques that had developed was counted for measurement. 5) Using the obtained virus infectivity, the antiviral activity was calculated according to the following formula (1). Antiviral activity value V = Ut - At (1) Ut: Virus infectivity (PFU / cm) of unprocessed glass substrate (Example 2) after standing for a specified time 2 ) At: Virus infectivity (PFU / cm) of the antiviral processed product (Example 1) after standing for a specified time 2 )

[0160] The antiviral evaluation results for Examples 1 and 2 are shown in Table 1. The antiviral activity was judged to be excellent if the antiviral activity value was 2.5 or higher after an action time of 24 hours, and was assigned a grade of "A." If the antiviral activity value was 1.5 or higher but less than 2.5, the antiviral activity was judged to be excellent and was assigned a grade of "B." If the antiviral activity value was less than 1.5, the antiviral activity was judged to be poor and was assigned a grade of "C." However, for Example 2, the antiviral activity value could not be calculated, but since the infectivity was about 100 times higher than that of Example 1, it was determined to have low antiviral activity and given a grade of "C."

[0161] [Table 1]

[0162] (Composition, thickness and appearance of antiviral coating film) For the glass of Example 1, the weight ratio of materials in the antiviral coating film, as well as the film thickness and appearance of the antiviral coating film, are shown in Table 2. Regarding the weight ratio of materials in the antiviral coating, the weight ratio of CuAlO2 and Si metal oxide was determined from the prepared paint. The thickness of the antiviral coating film was measured by cross-sectional SEM observation using Hitachi High-Tech's "SU8030" (product name). The appearance of the antiviral coating film was visually observed and the color was evaluated.

[0163] [Table 2]

[0164] (transmittance) The transmittance was checked for the glass of Example 1 and the glass substrate of Example 2. The transmittance was evaluated as spectral transmittance at wavelengths of 300 to 800 nm using a spectrophotometer "U-4100" (product name) manufactured by Hitachi High-Technologies Corporation. The results are shown in Figure 2.

[0165] As can be seen from Table 1, the antiviral coated glass of Example 1 had an antiviral activity value of 1.8 after 24 hours of action, indicating a high antiviral effect due to CuAlO2. Furthermore, Table 2 and FIG. 2 confirm that the glass with the antiviral coating film of Example 1 has transparency.

[0166] <Test Example 2> (Example 3) (Synthesis of CuAlO2 antiviral material bulk by solid-state reaction method) 350.2 g of Cu2O powder and 249.8 g of Al2O3 powder (both manufactured by Kojundo Chemical Laboratory) were weighed and mixed using a ball mill. The mixed powder was molded into a cylindrical shape with a diameter of 50.8 mm and a thickness of 5 mm using a uniaxial press, placed on a plate made of yttrium oxide-stabilized zirconium oxide, and placed in an electric furnace. This was then fired at 1200°C for 6 hours in an argon gas (Ar) atmosphere to reduce the oxygen partial pressure. The argon gas flow rate was set to 200 sccm.

[0167] (Example 4) (Synthesis of CuGaO2 antiviral bulk material by solid-state reaction method) 359.5 g of Cu2O powder and 340.1 g of Ga2O3 powder (both manufactured by Kojundo Chemical Laboratory) were weighed and mixed using a ball mill. The mixed powder was formed into a cylindrical shape with a diameter of 50.8 mm and a thickness of 5 mm using a uniaxial press, placed on a plate made of yttrium oxide-stabilized zirconium oxide, and placed in an electric furnace. This was then fired at 1200°C for 6 hours in an argon gas (Ar) atmosphere to reduce the oxygen partial pressure. The argon gas flow rate was set to 200 sccm.

[0168] (Example 5) For comparison with the case with an antiviral coating film and to calculate the antiviral activity value, an unprocessed glass substrate (thickness 2 mm) not coated with an antiviral coating film was prepared.

[0169] (Antiviral evaluation) An antiviral property evaluation test was conducted on the antiviral material bulks of Examples 3 and 4, and the glass substrate of Example 5. The evaluation was performed in the same manner as in Test Example 1. The size of the test pieces of Examples 3 and 4 was the same as that when they were prepared (Φ50.8 mm, thickness 5 mm), while the size of the test piece of Example 5 was 50 mm × 50 mm, thickness 2 mm. In Test Example 2, in formula (1) for calculating the antiviral activity value V, Example 5 is the unprocessed glass substrate, and Example 3 or Example 4 is the antiviral processed product. The antiviral evaluation results of Examples 3 to 5 are shown in Table 3.

[0170] [Table 3]

[0171] As can be seen from the results in Table 3, in Examples 3 and 4, the antiviral activity value after 1 hour of action was 2.5 or more, demonstrating an extremely excellent antiviral effect. For Example 5, although the antiviral activity value could not be calculated, the infectivity titer was orders of magnitude higher than those of Examples 3 and 4, and therefore the antiviral activity was judged to be low (rating C).

[0172] Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention. This application is based on a Japanese patent application (Patent Application No. 2020-125649) filed on July 22, 2020, the contents of which are incorporated herein by reference.

Claims

1. An antiviral material comprising a Cu-MO compound, wherein the Cu includes at least a monovalent state, and the M is Al or Ga.

2. The Cu-MO compound is CuMO ２ The antiviral material according to claim 1, comprising a delafossite-type crystal represented by the formula:

3. An antiviral material comprising a Cu-MM'-O compound, wherein the Cu includes at least a monovalent state, the M is Al or Ga, and the M' is Ag or Pd.

4. A laminate comprising a substrate and a thin film disposed on the substrate and comprising the antiviral material according to any one of claims 1 to 3.

5. A particle comprising the antiviral material according to any one of claims 1 to 3.

6. A paint comprising the particles of claim 5.

7. A coated body comprising a substrate and a coating film formed of the coating material according to claim 6, disposed on the substrate.

8. A fiber comprising the antiviral material according to any one of claims 1 to 3.

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