JP2023038822A - Article having antiviral microstructure, and method for transferring antiviral microstructure - Google Patents

Abstract

An object is to provide an article having an antiviral microstructure capable of inactivating viruses while exhibiting superhydrophobicity.
Kind Code: A1 An article 1 having an antiviral microstructure comprises an article 2 to be processed and a superhydrophobic layer M having an antiviral microstructure Ma (nanostructure) formed on the article 2. , wherein the superhydrophobic layer is made of a hydrophobic resin, and the hydrophobic resin contains an antiviral material. The nanostructure on the surface of the superhydrophobic layer M is formed by randomly arranging fine protrusions having needle-like or cone-like shapes with diameters decreasing from the root to the tip and sharpened at the tip, The fine protrusions have an average diameter of 10 nm to 400 nm, an average height of 30 nm to 1000 nm, and an average pitch of 10 nm to 500 nm.
[Selection drawing] Fig. 8

Description

TECHNICAL FIELD The present invention relates to an article comprising an antiviral microstructure, a transfer method of the antiviral microstructure and a virus inactivation method, and in particular, an article comprising an antiviral microstructure exhibiting superhydrophobicity and an antiviral microstructure. It relates to transcription methods and virus inactivation methods.

Viral infectious diseases, for example, infectious diseases caused by coronaviruses that cause novel coronavirus infectious disease (COVID-19), influenza viruses, noroviruses, rotaviruses, etc., have become serious social problems.

Patent Literature 1 describes an interior building material having a bactericidal surface comprising a metal substrate and a porous anodized layer formed on the metal substrate. The surface of the porous anodized layer having a bactericidal action includes a plurality of recesses having a two-dimensional size of more than 100 nm and less than 500 nm when viewed from the normal direction of the surface, and between the adjacent recesses A protrusion is formed, and the protrusion has a ridgeline formed by the intersection of side surfaces of a plurality of adjacent recesses.

JP 2019-150626 A

Although there are many reports on the bactericidal properties of microstructures (moth-eye structures) using an anodized porous alumina transfer mold, there has been almost no mention of antiviral properties. Unlike organisms such as pathogenic Escherichia coli, viruses are known to be difficult to inactivate. Even with known techniques that claim that pathogenic bacteria and viruses can be inactivated as a surface structure having an antibacterial effect, it does not necessarily exhibit an actual antiviral effect. The conventional moth-eye structure was a shape that was transferred with a porous alumina plate and had a wide pitch and a thick tip, so it did not exhibit an antiviral effect.

In addition, the present inventors have found that a water-repellent moth-eye structure cannot provide antiviral properties because bacteria and viruses cannot adhere to the surface. Specifically, the water-repellent moth-eye structure causes droplets to be spherical on the surface due to the water-repellent effect, so the bacteria or viruses inside the spherical droplets cannot contact the moth-eye structure, so antiviral properties cannot be obtained. rice field.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an article having an antiviral microstructure capable of inactivating viruses while exhibiting superhydrophobicity, and a method for transferring the antiviral microstructure. is to provide Another object of the present invention is to provide a virus inactivation method capable of inactivating viruses based on the shape of the microstructure while exhibiting superhydrophobicity.

As a result of intensive studies, the present inventors have found that a fine structure with a narrower pitch and a sharper tip than a moth-eye structure using anodized porous alumina is formed with a water-repellent resin containing an antiviral material. As a result, the inventors have found that antiviral action is exhibited while exhibiting superhydrophobicity.

According to the article having an antiviral microstructure of the present invention, the object is provided with an article to be processed, and a super water-repellent layer having a nanostructure formed on the article, The water-repellent layer is made of a hydrophobic resin, and the hydrophobic resin contains an antiviral material.
At this time, the nanostructure on the surface of the superhydrophobic layer is formed by randomly arranging fine protrusions having a needle-like or cone-like shape with sharpened tips that decrease in diameter from the root to the tip. Preferably, the fine projections have an average diameter of 10 nm to 400 nm, an average height of 30 nm to 1000 nm, and an average pitch of 10 nm to 500 nm.
At this time, the virus is preferably at least one selected from the group consisting of influenza virus, coronavirus, and norovirus.
At this time, the article is preferably at least one selected from the group including face shields, mouth shields, sanitary masks, partitions, smartphones, tablet terminals, touch panels, window glass, building materials, and spectacle lenses.

According to the method for transferring an antiviral microstructure of the present invention, the above problems are solved by: a transfer mold preparing step of preparing a transfer mold having a glassy carbon layer on its surface; a step of preparing an object to be processed; a step of curing the hydrophobic resin in a state in which the hydrophobic resin containing the antiviral material is applied between the surface of the object to be processed and the nanostructure formed of the cured hydrophobic resin; and the nanostructure on the surface of the superhydrophobic layer formed of the cured hydrophobic resin is antiviral.
At this time, the nanostructure on the surface of the superhydrophobic layer is formed by randomly arranging fine protrusions having a needle-like or cone-like shape with sharpened tips that decrease in diameter from the root to the tip. Preferably, the fine projections have an average diameter of 10 nm to 400 nm, an average height of 30 nm to 1000 nm, and an average pitch of 10 nm to 500 nm.

According to the virus inactivation method of the present invention, the problem is a virus inactivation method on the surface of a super water-repellent layer on which an antiviral nanostructure is formed, wherein the super water-repellent layer is made of a hydrophobic resin. and the hydrophobic resin contains an antiviral material.
At this time, the nanostructure on the surface of the superhydrophobic layer is formed by randomly arranging fine protrusions having a needle-like or cone-like shape with sharpened tips that decrease in diameter from the root to the tip. Preferably, the fine projections have an average diameter of 10 nm to 400 nm, an average height of 30 nm to 1000 nm, and an average pitch of 10 nm to 500 nm.
At this time, the virus is preferably at least one selected from the group consisting of influenza virus, coronavirus, and norovirus.

According to the article provided with an antiviral microstructure and the method for transferring an antiviral microstructure of the present invention, it is possible to inactivate viruses while having superhydrophobicity, and to create a hygienic and safe environment. . Moreover, according to the virus inactivation method of the present invention, it is possible to inactivate viruses based on the shape of the fine structure while exhibiting superhydrophobicity.

Specifically, by adding an antiviral material to a water-repellent transfer resin, it is possible to achieve low reflection and antifouling properties that combine antiviral properties and super water repellency.

In more detail, the low-reflection, anti-dirt, anti-virus film that exhibits super water repellency makes it possible to simply attach it to window glass (houses, cars, trains, ships, etc.) to prevent stains and anti-virus properties. Since the surface can be maintained, it is hygienic and it is possible to reduce the frequency of cleaning. In addition, by attaching it to the screen of a smartphone, tablet, personal computer, etc., it is difficult for droplets to adhere, and even if droplets adhere, it is possible to always maintain a hygienic surface due to the antiviral effect.

1 is a schematic cross-sectional view of an article comprising antiviral microstructures according to one embodiment of the present invention; FIG. 1 is a schematic cross-sectional view showing a transfer mold having a glassy carbon layer on its surface, which is used in the method for transferring an antiviral microstructure according to one embodiment of the present invention. FIG. 1 is a flow diagram illustrating a method of transferring antiviral microstructures according to one embodiment of the present invention; FIG. It is a graph which shows the reflectance of each sample. 4 is a graph showing the transmittance of each sample; 4 is an electron micrograph showing the state of the surface of the sample of Example 1. FIG. 4 is an electron micrograph showing the state of the surface of the sample of Example 2. FIG. It is the result of an antiviral performance test against influenza virus. It is the result of an antiviral performance test against feline calicivirus.

An article having an antiviral microstructure, a method for transferring an antiviral microstructure, and a virus inactivation method according to one embodiment (hereinafter referred to as the present embodiment) of the present invention will be described below with reference to FIGS. 1 to 9. explain.

<Article with antiviral microstructure>
As shown in FIG. 1, an article 1 having an antiviral microstructure of the present embodiment comprises an article 1 to be processed and a superhydrophobic layer M having a nanostructure formed on the article 1. , wherein the superhydrophobic layer M is made of a hydrophobic resin, and the hydrophobic resin contains an antiviral material.

(Processing object 2)
In the transfer method of the antiviral microstructure Ma of the present embodiment, the object to be processed 2 on which the superhydrophobic layer M and the antiviral microstructure Ma are to be formed is an object to be imparted with antiviral properties. , is not particularly limited.

Specific examples of the object to be processed 2 to be processed include protective equipment for preventing droplets such as face shields, mouth shields, sanitary masks, partitions (partition plates) for blocking contact with people, smartphones, tablet terminals, Liquid crystal displays, organic EL displays, various computers, televisions, various display devices such as plasma display panels, their touch panels and displays, building materials such as window glass, walls, and door knobs in buildings such as houses, public facilities, and medical facilities (especially walls of washrooms, bathrooms, toilets, etc.), window glass of vehicles such as automobiles, trains, and aircraft, mirrors, inner walls, anti-reflection sheets (anti-reflection films), anti-fouling sheets (anti-fouling films), anti-fog sheets (anti-fogging cloudy film), spectacle lenses made of transparent plastics, sunglasses lenses and the like, but are not limited to these articles.

The workpiece 2 has a surface 2a, but the shape of the surface 2a is not limited to a flat surface (flat plate shape), but may be a curved shape such as a curved surface (for example, a roll shape) or a combination of a flat surface and a curved surface. It may also be a complicated shape (irregular shape) or the inner surface of the hollow member. Since the method for forming an antiviral microstructure according to the present embodiment does not require a high-temperature process, it can be suitably applied to the object to be processed 2 containing a heat-sensitive substance (material) such as resin. It is possible.

The resin contained in the object to be treated may be either a thermoplastic resin or a thermosetting resin, such as polyethylene (high density, medium density or low density), polypropylene (isotactic type or syndiotactic type), Polyolefins such as polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), ethylene-propylene-butene copolymer, cyclic polyolefin, modified polyolefin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, Polyimide, polyamideimide, polycarbonate, poly-(4-methylpentene-1), ionomer, acrylic resin, polymethyl methacrylate, polybutyl (meth) acrylate, methyl (meth) acrylate-butyl (meth) acrylate copolymer, methyl (Meth)acrylate-styrene copolymer, acrylic-styrene copolymer (AS resin), butadiene-styrene copolymer, ethylene-vinyl alcohol copolymer (EVOH), polyethylene terephthalate (PET), polybutylene terephthalate (PBT) ), ethylene-terephthalate-isophthalate copolymer, polyester such as polyethylene naphthalate, polycyclohexylene dimethylene terephthalate (PCT), polyether, polyetherketone (PEK), polyetheretherketone (PEEK), polyetherimide , polyacetal (POM), polyphenylene oxide, modified polyphenylene oxide, polyarylate, aromatic polyester (liquid crystal polymer), polytetrafluoroethylene (PTFE), polyvinylidene fluoride, other fluorine resins, styrene, polyolefin, polyvinyl chloride Polyurethane, fluororubber, chlorinated polyethylene and other thermoplastic elastomers, epoxy resin, phenolic resin, urea resin, melamine resin, unsaturated polyester, silicone resin, polyurethane, nylon, nitrocellulose, cellulose acetate, cellulose Cellulosic resins such as acetate propionate, etc., or copolymers, blends, polymer alloys, etc. mainly composed of these, and the like, and one or more of these are combined (for example, two or more layers laminated body) may be used.

Examples of the glass contained in the object to be treated include silicate glass (quartz glass), alkali silicate glass, soda lime glass, potash lime glass, lead (alkali) glass, barium glass, and borosilicate glass.

Examples of metals contained in the object to be treated include gold, chromium, silver, copper, platinum, indium, palladium, iron, titanium, nickel, manganese, zinc, tin, tungsten, tantalum, and aluminum. In addition, stainless steel such as SUS316L, which is an alloy of the above metals, shape memory alloy such as Ti-Ni alloy or Cu-Al-Mn alloy, Cu-Zn alloy, Ni-Al alloy, titanium alloy, tantalum alloy, platinum alloy Alternatively, an alloy such as a tungsten alloy can also be used. In addition, the alloy is obtained by adding one or more kinds of metallic elements or non-metallic elements to the metallic element. The structures of alloys include eutectic alloys in which the component elements form separate crystals, solid solutions in which the component elements are completely dissolved, and components in which the component elements form intermetallic compounds or compounds of metals and non-metals. However, it is not necessarily limited to this.

Ceramics contained in the object to be treated include, for example, oxides (e.g., aluminum oxide, zinc oxide, titanium oxide, silicon oxide, zirconia, barium titanate), nitrides (e.g., silicon nitride, boron nitride), carbides ( Examples include silicon carbide), oxynitrides, and the like. A mixture of these can also be used.

Examples of metal oxides contained in the object to be treated include oxides containing aluminum, copper, gold, silver, platinum, indium, palladium, iron, nickel, titanium, chromium, manganese, zinc, tin, tungsten, etc. as metals. materials, indium tin oxide (ITO), _aluminum oxide ( _Al2O3 ), titanium oxide _{( TiO2} ), silicon oxide ( _SiO2 ), tin oxide ( _SnO2 , SnO), iron oxide ( _Fe2O3 , Fe ₃ O ₄ ), and composite oxides having perovskite, spinel, and ilmenite structures, but are not necessarily limited to these.

Metal nitrides contained in the object to be treated include titanium nitride (TiN), zirconium nitride (ZrN), vanadium nitride (VN), niobium nitride (NbN), tantalum nitride (TaN), chromium nitride (CrN, Cr ₂ N ), hafnium nitride (HfN), and the like, but are not necessarily limited to these.

(Super water-repellent layer M)
The article 1 having an antiviral microstructure of this embodiment comprises a superhydrophobic layer M having nanostructures formed on the article 1 . The superhydrophobic layer M is made of a hydrophobic resin, and the hydrophobic resin contains an antiviral material.

(hydrophobic resin)
The hydrophobic resin is not particularly limited as long as it exhibits water repellency when cured, but it is preferable to use a photocurable resin or thermosetting resin that exhibits water repellency when cured. . The photocurable resin or thermosetting resin is not particularly limited as long as it can be cured by irradiation with light such as ultraviolet rays or by heating, and acrylic resin, epoxy resin, urethane resin, etc. can be used. It is possible. It is preferable to use a hydrophobic resin doped with 2% to 20% of fluorine.

(antiviral material)
The antiviral material is not particularly limited as long as it exhibits antiviral properties and can be mixed with the hydrophobic resin. For example, metal-based or metal compound-based materials can be used as antiviral materials. Examples of metals contained in metal-based or metal compound-based materials include copper, silver, zinc, and nickel.

Nanoparticles of a metal-based or metal compound-based material may be used as the antiviral material. At this time, the antiviral material contains particles of at least one monovalent copper compound that is chloride, acetate, sulfide, iodide, bromide, peroxide, or thiocyanide as an active ingredient, It is preferred to use an antiviral agent characterized in that it inactivates viruses that come into contact with particles of monovalent copper compounds. At this time, the monovalent copper compound is, for example, cuprous chloride (CuCl), cuprous bromide (CuBr), cuprous iodide (CuI), cuprous acetate (Cu(CH ₃ COO)) , cuprous sulfide (Cu ₂ S), cuprous thiocyanate (CuSCN), and cuprous oxide (Cu ₂ O).

The article 1 has improved water repellency on the surface by laminating the super water-repellent layer M, and the water contact angle on the surface is 120° or more, preferably 130° or more, more preferably 140° or more. be. Since the water contact angle of the surface of the superhydrophobic layer M is within the above range, it has high water repellency, prevents droplets from adhering, and easily removes adhering stains and foreign matter by washing with water. It is possible to prevent fogging due to adhesion of water droplets.

The article 1 exhibits antiviral properties by laminating a super water-repellent layer M containing an antiviral material. Specifically, antiviral properties are exhibited by containing an antiviral material and forming a structure in which the pitch of the antiviral fine structure Ma is narrow and the tip is sharp.

The thickness of the superhydrophobic layer M may be appropriately selected according to the shape and application of the object 2 to be treated, and is preferably 1 nm or more and 50 μm or less, more preferably 5 nm or more and 30 μm or less, and more preferably. It is preferably 5 nm or more and 10 μm or less, more preferably 10 nm or more and 5.0 μm or less, further preferably 10 nm or more and 1.0 μm or less. If the thickness of the superhydrophobic layer M is too thin, it is not preferable from the viewpoint of durability. On the other hand, if the superhydrophobic layer is too thick, depending on the intended use of the object 2 to be treated, it may be undesirable from the viewpoints of reduced transmittance, reduced flexibility, weight reduction, and cost.

(Antiviral fine structure Ma)
The antiviral fine structure Ma is the fine structure of the surface of the superhydrophobic layer M laminated on the surface 2a of the object 2 to be treated. The superhydrophobic layer M and the antiviral microstructure Ma are formed by using a transfer mold T (FIG. 2) having a glassy carbon layer on the surface, which will be described later, using the transfer method of the antiviral microstructure Ma according to the present embodiment ( 3).

The antiviral microstructure Ma is composed of a cured hydrophobic photocurable resin or thermosetting resin, and is a fine projection having a shape with a diameter that decreases from its root to its tip. , fine protrusions having a needle-like or cone-like shape with sharpened tips are arranged randomly.

The fine protrusions constituting the antiviral microstructure Ma have an average diameter (D) of 10 nm to 400 nm, preferably 30 nm to 300 nm, particularly preferably 50 nm to 150 nm, and an average height (H) of , 30 nm to 1000 nm, preferably 50 nm to 700 nm, particularly preferably 100 nm to 500 nm, and an average pitch (P) of 10 nm to 500 nm, preferably 30 nm to 400 nm, particularly preferably 50 nm to 300 nm. and the tip average diameter (diameter at 10% of the height of the protrusion from the tip of the protrusion) is 10 to 60 nm, preferably 15 to 55 nm, particularly preferably 20 to 50 nm. In the specification of the present application, ◯ nm to Δnm mean ◯ nm or more and Δ nm or less.

The arithmetic mean height (Sa) of the surface of the antiviral microstructure Ma is 20 nm or more and 100 nm or less, preferably 25 nm or more and 80 nm or less, particularly preferably 30 nm or more and 70 nm or less. The arithmetic mean height (Sa) is a three-dimensional roughness parameter (three-dimensional height direction parameter) obtained by extending the arithmetic mean roughness (Ra), which is a two-dimensional roughness parameter, to three dimensions. The arithmetic average height (Sa) represents the average of the absolute values of the height differences of each point in the measurement target area.

The maximum height (Sz) of the surface of the antiviral microstructure Ma is 200 nm or more and 700 nm or less, preferably 250 nm or more and 600 nm or less, and particularly preferably 300 nm or more and 500 nm or less. The maximum height (Sz) is a three-dimensional parameter obtained by expanding the two-dimensional roughness parameter Rz. The maximum height (Sz) is the distance from the highest point to the lowest point on the surface in the measurement target area (in other words, the sum of the maximum surface peak height Sp and the maximum valley depth Sv). .

(Antiviral action)
The conventional moth-eye structure produced by transferring with a porous alumina plate did not exhibit an antiviral effect because the size of the microstructure itself was large, the pitch was wide, and the tip was thick. On the other hand, the antiviral microstructure Ma of the present embodiment has a sharp tip containing an antiviral material, and it is possible to inactivate viruses by narrowing the pitch. there is

In the article having antiviral microstructures, the method for transferring antiviral microstructures, and the method for inactivating viruses according to the present embodiment, viruses to be inactivated are not particularly limited. Examples of viruses that can be inactivated include various viruses, regardless of the type of genome or the presence or absence of an envelope, but include airborne and droplet-infected coronaviruses, influenza viruses, noroviruses, and rotaviruses. It is preferable to be targeted. In particular, it is preferable to target coronaviruses or influenza viruses that are enveloped viruses.

Examples of coronaviruses include SARS virus, which is the causative agent of severe acute respiratory syndrome (SARS), which was prevalent in 2003, and MERS virus, which is the causative agent of Middle East respiratory syndrome (MERS). , 2019 novel coronavirus (2019-nCoV, SARS-CoV-2), which is a coronavirus belonging to the SARS-related coronavirus (SARSr-CoV) that causes the new coronavirus infection (COVID-19), etc. However, it is not particularly limited.

Examples of influenza viruses include, but are not limited to, human influenza viruses, avian influenza viruses, swine influenza viruses, and the like.

Viruses can take time to develop vaccines and medicines because new viruses emerge and mutant viruses emerge due to mutation. can be inactivated regardless of the type or mutation.

<Transfer type T>
As shown in FIG. and a glassy carbon layer 30 formed on the underlayer 20, the glassy carbon layer 30 having an inverted microstructure RM on the surface 30a.

(Base material 10)
The substrate 10 is made of resin, rubber, glass, metal, alloy, ceramics (metal oxide, metal nitride, metal oxynitride), silicon wafer (Si wafer), compound semiconductor used for compound semiconductor substrate, power device It contains one or more substances selected from the group including solar cell materials such as silicon carbide (SiC) and silicon used for the substrate. When a flexible material such as rubber is used as the base material 10, when the antiviral microstructure Ma is transferred using the transfer mold T, it can be applied to curved or irregularly shaped articles (objects to be processed). , the transfer mold T can be brought into close contact with the shape of the article.

(Base layer 20)
Underlayer 20 contains one or more substances selected from the group including metals, alloys, ceramics (metal oxides, metal nitrides, metal oxynitrides), and silicon (Si).
The film thickness of the underlying layer 20 is preferably 10 nm or more and 500 nm or less.
When a material containing a resin (plastic or film) is used as the base material 10, it is preferable to use Cr, Ti, _{Ta2O5 ,} a combination thereof, or the like as the base layer 20. FIG.
By adding the base layer to the surface of the base material 10 , the adhesiveness of the glassy carbon layer 30 is improved, and film cracking in the glassy carbon layer 30 can be suppressed.

(Glassy carbon layer 30)
The glassy carbon layer 30 is a layer containing glassy carbon formed on the underlying layer 20 . The film thickness of the glassy carbon layer 30 is preferably 300 nm or more and 5 μm or less. Here, glassy carbon is also called glassy carbon or amorphous carbon, and is black in appearance, glassy and amorphous carbon, and has a homogeneous and dense structure. Glassy carbon has the same properties as other carbon materials, such as electrical conductivity, chemical stability, heat resistance, and high purity. In addition, glassy carbon has an excellent feature that the material surface does not powder and fall off. The general characteristics of glassy carbon are that it is lightweight with a density of 1.45 to 1.60 g/cm ³ , has a high bending strength of 50 to 200 MPa, and is resistant to acids such as sulfuric acid and hydrochloric acid and has corrosion resistance. . As for the electrical conductivity, the specific electrical resistance is 4 to 20 mΩcm, which is slightly higher than that of graphite, but the gas permeability is as low as 10 −9 to 10 ⁻¹² cm ² /s.

The glassy carbon layer 30 has an inverted microstructure RM on its surface 30a. Here, the inverted microstructure RM refers to the structure of the surface of the transcription type T that can form the antiviral microstructure Ma.

The reversed microstructure RM in the transfer mold T according to this embodiment is formed by randomly arranging conical holes. At this time, the glassy carbon microstructure constituting the inverted microstructure RM has an average diameter (D) of 10 nm to 400 nm, preferably 30 nm to 300 nm, particularly preferably 50 nm to 150 nm, and an average height of height (H) is 30 nm to 1000 nm, preferably 50 nm to 700 nm, particularly preferably 100 nm to 500 nm, and an average pitch (P) is 10 nm to 500 nm, preferably 30 nm to 400 nm, particularly preferably 50 nm to It is in the range of 300 nm.

In the transfer mold T according to this embodiment, the arithmetic mean height (Sa) of the surface 30a of the glassy carbon layer 30 is 50 nm or more and 500 nm or less.

In the transfer mold T according to this embodiment, the maximum height (Sz) of the surface 30a of the glassy carbon layer 30 is 200 nm or more and 700 nm or less.

The shape of the transfer mold T includes one or more shapes selected from the group including roll shape, flat plate shape, and deformed shape.

<Transfer method of antiviral microstructure>
Using the transfer mold T having the glassy carbon layer 30 on the surface, the antiviral microstructure Ma can be transferred to the surface of the object 2 to be processed, as shown in FIG.

Specifically, the method for transferring an antiviral microstructure of the present embodiment comprises a step of preparing a transfer mold T having a glassy carbon layer 30 on its surface (step S11), and preparing the object 2 to be processed. a step (step S12), a step of curing the hydrophobic resin in a state in which the hydrophobic resin containing an antiviral material is applied between the transfer mold T and the surface 2a of the object 2; (Step S13) and a step (Step S14) of peeling off the transfer mold T from the nanostructure (antiviral fine structure Ma) formed of the cured hydrophobic resin (Step S14). In addition, the nanostructure on the surface of the superhydrophobic layer M formed of the hydrophobic resin is antiviral.

Through steps S11 to S14 described above, the surface 2a of the object 2 to be treated can be given antiviral properties. Specifically, a superhydrophobic nanostructure (antiviral fine structure Ma) made of a cured hydrophobic resin can be transferred to the surface 2a of the object 2 to be processed. Each step will be described in detail below.

(Transfer mold preparation process)
In the transfer mold preparation step (step S11), a transfer mold T having a glassy carbon layer on the surface shown in FIG. a glassy carbon layer 30 formed on the underlayer 20, the glassy carbon layer 30 providing a transfer mold T having an inverted microstructure RM on a surface 30a. Here, the inverted microstructure RM is formed by randomly arranging conical holes. At this time, the glassy carbon microstructure constituting the inverted microstructure RM has an average diameter (D) of 10 nm to 400 nm, preferably 30 nm to 300 nm, particularly preferably 50 nm to 150 nm, and an average height of height (H) is 30 nm to 1000 nm, preferably 50 nm to 700 nm, particularly preferably 100 nm to 500 nm, and an average pitch (P) is 10 nm to 500 nm, preferably 30 nm to 400 nm, particularly preferably 500 nm to It is in the range of 300 nm.

(Step of preparing an object to be processed)
In the step of preparing an object to be processed (step S12), the object to be processed 2 to be processed is prepared. At this time, the surface 2a of the object to be treated 2 may be subjected to pretreatment such as cleaning or electrification to improve the film-forming property (laminating property) of the hydrophobic resin.

(Step of curing hydrophobic resin)
In the step of curing the hydrophobic resin (step S13), the hydrophobic resin is cured while the hydrophobic resin containing the antiviral material is applied between the transfer mold T and the surface 100a of the workpiece 2. Let

At this time, when the shape of the transfer mold T is roll-shaped, the inverted fine structure RM, which is the surface structure of the transfer mold T, is covered by rotating the roll-shaped transfer mold T around its axis. It can be continuously transferred to the object 2 to be processed. When a roll-shaped film is used as the workpiece, it is possible to adopt a roll-to-roll system.

When a flexible material is used as the base material 10 of the transfer mold T, a combination of pressure reduction and pressure is applied to make the flexible transfer mold T in close contact with the object 2 to be processed. The photocurable resin can be cured by irradiating the photocurable resin with light. By using the transfer mold T having flexibility, it is possible to transfer the antiviral fine structure even to the object 2 having an irregular shape.

(Step of removing transfer mold)
In the step of peeling off the transfer mold (step S14), the transfer mold T is peeled off from the nanostructure (antiviral fine structure Ma) formed of the cured hydrophobic resin.

<Virus inactivation method>
Viruses can be inactivated using the antiviral microstructures Ma (nanostructures) described above. Specifically, the virus inactivation method of the present embodiment is a virus inactivation method on the surface of the superhydrophobic layer M on which an antiviral nanostructure (antiviral fine structure Ma) is formed, The superhydrophobic layer M is made of a hydrophobic resin, and the hydrophobic resin contains an antiviral material.

It was thought that the superhydrophobic moth-eye structure (nanostructure) is a surface that does not allow viruses to adhere, but when foreign matter such as dust is present, the virus will adhere to the foreign matter starting from the foreign matter. Furthermore, when droplets or the like adhere under the same conditions, the droplets become spherical, and the virus cannot touch the moth-eye structure, so that the antiviral effect cannot be obtained. However, by forming the super water-repellent layer M with a hydrophobic resin containing an antiviral material, an antiviral effect can be obtained even for spherical droplets, so it is possible to always maintain a sanitary surface. becomes. In addition, the moth-eye structure provides low reflection, and the water-repellent resin provides an antifouling effect. Since the contact angle of water on the surface of the moth-eye structure, which is super water-repellent, is about 150°, it becomes an antiviral surface to which droplets and sweat do not adhere. In addition, even if droplets adhere to the surface of the moth-eye structure for some reason, hygiene is maintained due to the effect of the antiviral material.

In this embodiment, the article provided with an antiviral microstructure, the method for transferring the antiviral microstructure, and the method for inactivating virus according to the present invention have been mainly described. However, the above embodiment is merely an example for facilitating understanding of the present invention, and does not limit the present invention. The present invention can be modified and improved without departing from its spirit, and the present invention includes equivalents thereof.

Specific examples of the antiviral microstructure-containing article, the antiviral microstructure transfer method, and the virus inactivation method of the present invention will be described below, but the present invention is not limited thereto.

<Transfer plate used>
(transfer type with glassy carbon layer)
As a transfer mold with a glassy carbon layer, on its surface, an inverted microstructure has an average diameter (D) of 50-350 nm, an average height (H) of 200-450 nm, and an average pitch (P) of 20-300 nm. was used. The transfer mold of Example 1 can be prepared by the method described in JP-A-2020-76996.

The above parameters of the transfer plate are values obtained by observing the state of the surface using a field emission scanning electron microscope (FE-SEM, S-4300, manufactured by Hitachi High-Technologies Corporation).

<Transfer of fine structure>
A transfer mold was used to transfer the microstructure. The transfer mold was coated with a fluorine-based release agent (manufactured by Daikin Industries, Ltd., product name: UD-509) for release treatment. A triacetylcellulose film (TAC film) was used as an object (article) to be treated.

Next, as an antiviral material, a monovalent copper compound nanoparticle dispersion (manufactured by NBC Meshtec Co., Ltd., Cufitec (registered trademark) dispersion) was added at 0 wt% (Comparative Example 1) and 10 wt% (Example 1). , 20 wt % (Example 2) UV curable resin (acrylic resin, manufactured by Origin Electric Co., Ltd., product name: UV Coat TP), which is a hydrophobic resin, was prepared. The added amount (wt%) of the antiviral material indicates the ratio to the hydrophobic resin solution. A hydrophobic resin containing an antiviral material is applied to the surface of the transfer mold, the TAC film to be treated is adhered, and ultraviolet light (metal halide lamp light source, wavelength 200 nm to 450 nm, intensity 600 mJ, irradiation time 40 seconds) is applied. was irradiated for curing. Then, a TAC film having a surface fine structure (nanostructure) was obtained by separating the transfer mold from the surface fine structure formed of the cured photocurable resin.

・Comparative Example 1: 0% antiviral material
・Example 1: 10% antiviral material
・Example 2: 20% antiviral material

<Evaluation of fine structure>
An evaluation of the transferred microstructure was performed. Specifically, the transferred fine structure was subjected to spectroscopic measurement, surface state observation, surface roughness measurement, and contact angle evaluation.

(1. Spectral measurement)
The transmittance and reflectance of each sample were measured in the wavelength range from 400 nm to 700 nm using a spectrophotometer (U-4100, manufactured by Hitachi High-Technologies Corporation). The results of spectroscopic measurements are shown in FIGS. 3 and 4. FIG. FIG. 4 is a graph showing the reflectance of each sample. FIG. 5 is a graph showing the transmittance of each sample. The reflectance was as low as 0.4% or less in the range of 400 nm to 700 nm (Fig. 4). The transmittance was as high as 93% or more in the range of 450 nm to 700 nm (Fig. 5). Each parameter is shown in Table 1 below. The cloudiness (haze value) was measured at 25° C. using a haze meter (manufactured by Suga Test Co., Ltd., model number HGM-2DP).

(2. Observation of surface condition)
6 and 7 show the results of observing the state of the surface of the transferred microstructure using a field emission scanning electron microscope (FE-SEM, S-4300, manufactured by Hitachi High-Technologies Corporation). 6 is an electron micrograph showing the state of the surface of the sample of Example 1. FIG. 7 is an electron micrograph showing the state of the surface of the sample of Example 2. FIG.

In the samples of Examples 1 and 2, the transferred microstructures consisted of randomly arranged fine protrusions having needle-like or cone-like shapes with sharpened tips and tapered diameters from the base to the tip. was formed. The fine protrusions had an average diameter of 100 nm or less, an average tip diameter of 25 nm or less, an average height (H) of 150 nm, and an average pitch of 100 nm. Here, the tip average diameter is the diameter at a position 10% of the height of the protrusion from the tip of the protrusion.

In the samples of Examples 1 and 2, the addition of the antiviral material did not change the shape of the nanostructures. No particles of antiviral material were deposited on the tips of the nanostructures. In addition, since the monovalent copper compound nanoparticles contained in the antiviral material have a diameter of several hundred nm, they cannot adhere to the tips of the nanostructures. In other words, the nanoparticles contained in the antiviral material are uniformly dispersed inside the hydrophobic resin, thereby exhibiting the antiviral properties described below.

(3. Measurement of surface roughness)
The surface roughness of the transferred microstructure of each sample was evaluated. Specifically, an atomic force microscope (AFM, Innova (manufactured by Bruker AXS K.K.)) was used to measure the arithmetic mean height (Sa) and the maximum height (Sz) of the surface of each sample.

The arithmetic mean height (Sa) of the surface of the transfer mold provided with the glassy carbon layer (that is, the surface of the glassy carbon layer) is in the range of 50 nm or more and 70 nm or less, and the maximum height (Sz) is in the range of 400 nm or more and 500 nm or less. was inside.

The arithmetic mean height (Sa) of the surface fine structure in Examples 1 and 2 was in the range of 50 nm or more and 500 nm or less, and the maximum height (Sz) was in the range of 200 nm or more and 700 nm or less.

(4. Contact angle measurement)
The contact angles on the surfaces of the samples of Examples 1 and 2 were measured at 25° C. using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., model number CA-X). The contact angle on the surface of the sample of Example 1 was 145°, and the contact angle on the surface of the sample of Example 2 was 147°. In other words, it was found that all the samples exhibited superhydrophobicity.

<Antiviral performance test>
Each sample was tested for antiviral performance. The test was performed by a method according to the SIAA certification test (ISO21702:2019).

(Test overview)
Virus A: Influenza A virus (H3N2, A/Hong Kong/8/68), size 80-120 nm
・Host cell: MDCK cell (canine kidney-derived cell line)
・Reaction conditions: 25°C, 6 hours, 24 hours ・Washing solution: SCDLP medium ・Infectivity titer measurement method: Plaque method

Virus B: Feline calicivirus F-9, size about 30 nm
・Host cell: CRFK cell (cat kidney-derived cell)
・Reaction conditions: 25°C, 6 hours, 24 hours ・Washing solution: SCDLP medium ・Infectivity titer measurement method: Plaque method

(test operation)
a) A sample piece (5×5 cm) was attached to the bottom of a petri dish.
b) 400 μL of the virus solution was inoculated onto the sample piece and covered with a PET film (4×4 cm). Specifically, the virus solution was diluted with an agar solution, and the sample was inoculated with 400 μL of the virus solution and covered with a cover film.
c) Leave at 25° C. for 6 hours and 24 hours.
d) 10 mL of washing solution was added and the virus was washed out by pipetting.
e) The virus infectivity titer in the washout was measured by the plaque method.

(Test result 1: influenza virus)
Results for influenza virus (enveloped) are shown in FIG. 8 and Table 2 below.

The conditions for establishing the test were that the logarithm of the infectivity titer immediately after inoculation of the unprocessed test piece (Comparative Example 1) satisfies the following equation.
(L _max −L _min )/L _mean ≦0.2
L _max : Maximum logarithmic value of infection titer L _min : Minimum logarithmic value of infectious titer L _mean : Average logarithmic value of infectious titer of 3 specimens→Comparative Example 1: 0.014, established/unprocessed test The average infectious titer immediately after inoculation of the piece was 2.5×10 ⁵ to 1.2×10 ⁶ PFU/cm ² →Comparative Example 1: 3.7×10 ⁵ PFU/cm ² . The infection titer after an arbitrary time is 6.2×10 ² PFU/cm ² or more for all 3 specimens→Comparative Example 1 (24 hours standing): 8.1×10 ⁴ PFU/cm ² or more, established

The evaluation criteria are as follows.
・ Antiviral activity value: R = (U _t - U ₀ ) - (A _t - U ₀ ) = U _t - A _t
U ₀ : Average value of the infection titer logarithm value of 3 specimens immediately after virus inoculation of the unprocessed product U _t : Average value of the infection titer logarithm value of 3 specimens after standing for an arbitrary time after the virus inoculation of the unprocessed product _At : Average value/reduction rate of infection titer log value of 3 specimens after standing for an arbitrary time after virus inoculation of processed product: (10^U _t -10^A _t )/10^U _t × 100

*1: Not calculated based on the definition of antiviral activity value.
*2: The reduction rate was calculated from the number of inoculated viruses.

(Test result 2: feline calicivirus)
Results for feline calicivirus (non-enveloped) are shown in Figure 9 and Table 3 below.

The conditions for establishing the test were that the logarithm of the infectivity titer immediately after inoculation of the unprocessed test piece (Comparative Example 1) satisfies the following equation.
(L _max −L _min )/L _mean ≦0.2
→Comparative Example 1: 0.036, the average infectivity value immediately after inoculation of the established/unprocessed test piece is 2.5×10 ⁵ to 1.2×10 ⁶ PFU/cm ² →Comparative Example 1: 1.0× 10 ⁶ PFU/cm ² , the infection titer of the established/unprocessed test piece after an arbitrary time is 6.2 × 10 ² PFU/cm ² or more for all three specimens → Comparative Example 1 (24 hours standing): 3.3 ×10 ⁴ PFU/cm ² or more, established

For both influenza virus and feline calicivirus, the virus infectivity reached the detection limit after standing still for 24 hours, and the antiviral activity value was 4.0 or more, demonstrating antiviral performance. In addition, it was confirmed that the infectivity titers tended to decrease in both the samples of Examples 1 and 2 even after standing for 6 hours.

Since the sample of Comparative Example 1, to which no antiviral material was added, had no antiviral properties, it was shown that by adding an antiviral material to a hydrophobic resin, both superhydrophobicity and antiviral properties can be achieved.

From the above results, it was found that the antiviral microstructure of the present embodiment exhibits a virus inactivating effect, ie, antiviral properties, even for viruses with a size of about 100 nm and small viruses with a size of about 30 nm. In addition, it was found that the antiviral microstructure of the present embodiment exhibits antiviral properties against both enveloped viruses and non-enveloped viruses.

The novel coronavirus (SARS-CoV-2), which causes the novel coronavirus infectious disease (COVID-19), is a virus having an envelope of about 100 nm, which is the same size as influenza virus. It was suggested that the sexual fine structure can also inactivate the novel coronavirus.

1 Article with antiviral microstructure 2 Object to be processed (article)
2a Surface M Superhydrophobic layer Ma Antiviral microstructure (nanostructure)
T transfer mold 10 substrate 10a substrate surface 20 underlayer 30 glassy carbon layer 30a surface of glassy carbon layer RM inverted microstructure

TECHNICAL FIELD The present invention relates to an article comprising antiviral microstructures and a method for transferring antiviral microstructures, and in particular to an article comprising antiviral microstructures exhibiting superhydrophobicity and a method for transferring antiviral microstructures. Regarding .

According to the article having an antiviral microstructure of the present invention, the object is provided with an article to be processed, and a super water-repellent layer having a nanostructure formed on the article, The water-repellent layer is formed of a hydrophobic resin, the hydrophobic resin contains an antiviral material , and the nanostructure on the surface of the super-water-repellent layer decreases in diameter from the root to the tip, Fine protrusions having a sharpened needle-like or cone-like shape are randomly arranged, and the fine protrusions have an average diameter of 10 nm to 400 nm and an average height of 30 nm to 1000 nm. and the average pitch is in the range of 10 nm to 500 nm, and it is possible to inactivate one or more viruses selected from the group consisting of influenza virus, coronavirus, and norovirus, SIAA certification test (ISO21702 : 2019), the virus reduction rate after 24 hours is 99.99 or more .
At this time, the article is preferably at least one selected from the group including face shields, mouth shields, sanitary masks, partitions, smartphones, tablet terminals, touch panels, window glass, building materials, and spectacle lenses.

According to the method for transferring an antiviral microstructure of the present invention, the above problems are solved by: a transfer mold preparing step of preparing a transfer mold having a glassy carbon layer on its surface; a step of preparing an object to be processed; a step of curing the hydrophobic resin in a state in which the hydrophobic resin containing the antiviral material is applied between the surface of the object to be processed and the nanostructure formed of the cured hydrophobic resin; and removing the transfer mold from the surface of the superhydrophobic layer, wherein the nanostructure on the surface of the superhydrophobic layer formed of the cured hydrophobic resin is antiviral , and the surface of the superhydrophobic layer is The nanostructure of is formed by randomly arranging fine protrusions having a needle-like or cone-like shape with a diameter decreasing from the root to the tip and a sharpened tip, and the average of the fine protrusions Diameter is 10 nm to 400 nm, average height is 30 nm to 1000 nm, average pitch is in the range of 10 nm to 500 nm, and one or more selected from the group consisting of influenza virus, coronavirus, and norovirus. It is possible to inactivate the virus, and the virus reduction rate after 24 hours is 99.99 or more in a method according to the SIAA certification test (ISO21702: 2019) .

According to the article having an antiviral microstructure of the present invention, the object is provided with an article to be processed, and a super water-repellent layer having a nanostructure formed on the article, The water-repellent layer is formed of a hydrophobic resin, the hydrophobic resin contains 10 wt% or more of an antiviral material, and the antiviral material is chloride, acetate, sulfide, iodide, bromide, Nanoparticles of at least one monovalent copper compound that is a peroxide or a thiocyanide, wherein the nanostructures on the surface of the superhydrophobic layer are tapered from the root to the tip, and the tip is sharp. Fine projections having a modified needle-like or cone-like shape are randomly arranged, and the fine projections have an average diameter of 10 nm to 400 nm and an average height of 30 nm to 1000 nm. , the average pitch is in the range of 10 nm to 500 nm, it is possible to inactivate one or more viruses selected from the group consisting of influenza virus, coronavirus, and norovirus, and the SIAA certification test (ISO21702: 2019 ), the virus reduction rate after 24 hours is greater than 99.994 .
At this time, the article is preferably at least one selected from the group including face shields, mouth shields, sanitary masks, partitions, smartphones, tablet terminals, touch panels, window glass, building materials, and spectacle lenses.

According to the method for transferring an antiviral microstructure of the present invention, the above problems are solved by: a transfer mold preparing step of preparing a transfer mold having a glassy carbon layer on its surface; a step of preparing an object to be processed; Antiviral nanoparticles of at least one monovalent copper compound that is chloride, acetate, sulfide, iodide, bromide, peroxide, or thiocyanide between the surface of the object to be treated a step of curing the hydrophobic resin in a state in which a hydrophobic resin containing 10 wt % or more of a hydrophobic material is applied; and a step of peeling the transfer mold from the nanostructure formed of the cured hydrophobic resin. , wherein the nanostructures on the surface of the superhydrophobic layer formed of the cured hydrophobic resin are antiviral, and the nanostructures on the surface of the superhydrophobic layer extend from the root to the tip Fine protrusions having a needle-like or cone-like shape with a sharpened tip are arranged randomly and formed, and the average diameter of the fine protrusions is 10 nm to 400 nm, and the average The height is 30 nm to 1000 nm, the average pitch is in the range of 10 nm to 500 nm, and it is possible to inactivate one or more viruses selected from the group consisting of influenza virus, coronavirus, and norovirus. Yes, and the virus reduction rate after 24 hours is greater than 99.994 in a method according to the SIAA certification test (ISO21702:2019).

Claims (9)

an article that is a workpiece;
a superhydrophobic layer having a nanostructure formed on the article,
The superhydrophobic layer is formed of a hydrophobic resin,
An article comprising an antiviral microstructure, wherein said hydrophobic resin contains an antiviral material. The nanostructure on the surface of the superhydrophobic layer is formed by randomly arranging fine protrusions having a needle-like or cone-like shape with a diameter decreasing from the root to the tip and having a sharpened tip. ,
The fine protrusions have an average diameter of 10 nm to 400 nm, an average height of 30 nm to 1000 nm, and an average pitch of 10 nm to 500 nm. Articles with viral microstructures. 3. The article according to claim 2, wherein the virus is at least one selected from the group consisting of influenza virus, coronavirus, and norovirus. The article is at least one or more selected from the group including face shields, mouth shields, sanitary masks, partitions, smartphones, tablet terminals, touch panels, window glass, building materials, and spectacle lenses. 4. An article comprising the antiviral microstructure according to any one of clauses 3-3. A transfer mold preparation step of preparing a transfer mold having a glassy carbon layer on its surface;
A step of preparing an object to be processed;
a step of curing the hydrophobic resin in a state in which the hydrophobic resin containing an antiviral material is applied between the transfer mold and the surface of the object;
exfoliating the transfer mold from the nanostructures formed of the cured hydrophobic resin;
A method for transferring an antiviral fine structure, wherein the nanostructure on the surface of the superhydrophobic layer formed of the cured hydrophobic resin is antiviral. The nanostructure on the surface of the superhydrophobic layer is formed by randomly arranging fine protrusions having a needle-like or cone-like shape with a diameter decreasing from the root to the tip and having a sharpened tip. ,
The fine protrusions have an average diameter of 10 nm to 400 nm, an average height of 30 nm to 1000 nm, and an average pitch of 10 nm to 500 nm. Viral fine structure transfer method. A virus inactivation method on the surface of a superhydrophobic layer having an antiviral nanostructure, comprising:
The superhydrophobic layer is formed of a hydrophobic resin,
A virus inactivation method, wherein the hydrophobic resin contains an antiviral material. The nanostructure on the surface of the superhydrophobic layer is formed by randomly arranging fine protrusions having a needle-like or cone-like shape with a diameter decreasing from the root to the tip and having a sharpened tip. ,
The virus according to claim 7, wherein the fine protrusions have an average diameter of 10 nm to 400 nm, an average height of 30 nm to 1000 nm, and an average pitch of 10 nm to 500 nm. Inactivation method. 9. The article according to claim 7 or 8, wherein the virus is at least one selected from the group consisting of influenza virus, coronavirus, and norovirus.

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