Antiviral laminate and antiviral container

Abstract

To provide a laminate using a small amount of antiviral agent, the laminate capable of exerting sufficient antiviral performance, while difficult to fall the antiviral agent, and further capable of exhibiting abrasion resistance at transportation.SOLUTION: An antiviral laminate is obtained through forming a coating layer having antiviral properties on a surface of a base material 11. The coating layer includes a layer at least with an under coating layer 12 and an upper coating layer 13 laminated in this order from the base material 11 side. The under coating layer 12 is a layer with an application of a composition in which the antiviral agent is dispersed in a resin binder. The antiviral agent is inorganic particles. The upper coating layer 13 is a layer with an application of a composition in which the antiviral agent is not dispersed in a resin binder.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a laminate having antiviral properties and an antiviral container formed from this laminate. [Background technology]

[0002] As is well known, containers are indispensable in modern life. For example, many products, including food, are sold in containers made of paper, plastic, metal, glass, etc.

[0003] These products are placed in containers and displayed on the shelves of supermarkets and other stores, where an unspecified number of consumers pick up the products, check the contents, quality, expiry date, price, etc. of the products, and consider whether to purchase them or not. Then, of the many products that they have picked up and considered in this way, they purchase some of the products and return the rest to their original place.

[0004] Recently, the business model of buying and selling goods and services over the Internet, known as Electronic Commerce (EC), has become popular, and there is also a sales channel in which goods arrive at one's home wrapped in shipping materials after passing through many places and people via logistics.

[0005] However, modern life is exposed to the risk of infection by various viruses. Many of these viruses do not infect humans, but some do. Humans can become infected with a virus, for example, when an infected person touches a product container as an infection source, and the virus-containing body fluid adheres to the outer surface of the container, and then another person touches the container and takes in the virus in the body fluid.

[0006] In order to prevent indirect contact infection through product containers, a film made by kneading an antiviral agent has been proposed (Patent Document 1). Even if an infected person, who is the source of infection, touches the container and their bodily fluids adhere to it, a container made from this film can reduce the infectivity of the virus in the bodily fluids, so that even if another person touches the container, the risk of infection can be reduced.

[0007] However, body fluids come into contact only with the outer surface of the container, and the only antiviral agent that reduces the infectivity of the virus is the antiviral agent located on the outer surface of the container. In contrast, the antiviral agent is uniformly distributed throughout the container, so most of the antiviral agent does not exert its function. For this reason, there is a problem in that a large amount of antiviral agent far exceeding the necessary amount is required for this container.

[0008] On the other hand, Patent Document 2 proposes a film in which a powdered antiviral agent is sprayed and attached to the surface. This film can reduce the infectivity of viruses attached to the surface, as with the film of Patent Document 1. Moreover, since the antiviral agent is only attached to the film surface, only the minimum amount of antiviral agent is required.

[0009] However, in this film, since the powdered antiviral agent is simply attached to the surface, the antiviral agent is easily detached from the film surface, which poses a problem that the antiviral performance itself is lost due to the detachment.

[0010] On the other hand, in Patent Document 3, a powdered antiviral agent is added to a varnish containing a resin component and applied to the surface of a substrate, thereby providing the antiviral agent for a long period of time on the surface of a product that is made of a processed substrate. It can be distributed and exerts antiviral properties for a long period of time.

[0011] However, the antiviral agent is made of inorganic particles containing metal components such as Ag and Cu. The inorganic particles exposed on the surface are worn away by friction between product surfaces, particularly during distribution and transportation, resulting in scratches and the generation of foreign matter (inorganic particle powder), and thus causing deterioration in product quality. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] International Publication No. 2013 / 005446 [Patent Document 2] JP 2018-134753 A [Patent Document 3] Patent application 2020-148913 Summary of the Invention [Problem to be solved by the invention]

[0013] Therefore, an object of the present invention is to provide an antiviral laminate that uses a small amount of an antiviral agent, exhibits sufficient antiviral performance, is less likely to cause the antiviral agent to fall off, and exhibits abrasion resistance during transportation. [Means for solving the problem]

[0014] That is, the invention described in claim 1 is an anti-viral laminate comprising a coating layer having anti-viral properties formed on the surface of a substrate, The coating layer is disposed on the substrate side. From the above, an intermediate layer, an undercoat layer, and an overcoat layer having a thickness of 0.5 μm or more and 5 μm or less are included. The antiviral agent is dispersed in a resin binder, and the undercoat coating layer is a layer coated with the antiviral agent. The above The antiviral agent is an inorganic particle, and the top coat layer is a resin binder. The above A layer of a composition that does not have an antiviral agent dispersed in it The intermediate layer and the resin binder of the undercoat coating layer are made of a polyester resin. The antiviral laminate is characterized by the above.

[0015] Next, the invention described in claim 2 is the anti-viral laminate according to claim 1, characterized in that the base material is made of paper, resin, metal, a metal compound, or a laminate thereof.

[0016] Next, the invention described in claim 3 is the anti-viral laminate described in claim 1 or 2, characterized in that at least the top coating layer among the coating layers contains a slip agent such as micro wax, silicone oil, resin beads, etc.

[0019] next, Claim 4 The invention described in is characterized in that the antiviral agent is composed of a metal or a compound thereof represented by the element symbol Ag, Cu, Sb, Ir, Ti, Ge, Sn, Tl, Pt, Pd, Bi, Au, Fe, Co, Ni, Zn, or In. Any of claims 1 to 3 The antiviral laminate according to claim 1,

[0022] next, Claim 5 The invention described in Any of claims 1 to 4 1. An anti-viral container comprising the anti-viral laminate described in 1., wherein the coating layer is disposed on the outer surface of the container. Effect of the Invention

[0023] In the present invention, the antiviral agent is not blended throughout the laminate, but is only contained in the coating layer on the substrate surface, so only a small amount of antiviral agent is required. However, the position where the antiviral agent is placed is very close to the surface to which viruses adhere, so there are many opportunities for contact with the adhering viruses. For this reason, high antiviral performance is achieved even with a low blending rate of the antiviral agent.

[0024] In addition, since the antiviral agent is dispersed in the resin binder, it does not fall off and exhibits excellent antiviral performance for a long period of time.

[0025] Furthermore, because the composition in which the antiviral agent is dispersed is not applied to the surface of the antiviral laminate, it is possible to prevent the antiviral agent from falling off due to friction during transportation and to prevent the product surface from being scratched, thereby maintaining product quality. [Brief description of the drawings]

[0026] [Figure 1] 1(a) to (c) are cross-sectional views showing specific examples of the anti-viral laminate of the present invention. [Diagram 2] 2(a) to (c) are cross-sectional views showing sheets of comparative examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Specific examples of the present disclosure will now be described with reference to the accompanying drawings, in which: Figures 1(a) to (c) are cross-sectional views showing three specific examples of the antiviral laminate of the present invention.

[0028] The antiviral laminate of the present invention is formed by forming an antiviral coating layer on the surface of a substrate 11. The coating layer is composed of at least an undercoat coating layer 12 and an overcoat coating layer 13 laminated in this order from the substrate 11 side.

[0029] Of the three specific examples, the antiviral laminate 10A according to the first specific example is configured by forming an undercoat coating layer 12 containing an antiviral agent on the surface of a substrate 11, and further forming an overcoat coating layer 13 containing no antiviral agent thereon (see FIG. 1(a)). The undercoat coating layer 12 has a single-layer structure, and is laminated directly on the substrate 11 without any other layer being interposed between the substrate 11 surface and the undercoat coating layer 12.

[0030] Moreover, the antiviral laminate 10B according to the second specific example is configured by forming an undercoat coating layer 12 and an overcoat coating layer 13 on the surface of a substrate 11 via an intermediate layer 14 (see FIG. 1(b)). The undercoat coating layer 12 has a single layer structure, and is laminated on the substrate 11 via the intermediate layer 14.

[0031] The antiviral laminate 10C according to the third specific example is constructed by directly forming an undercoat coating layer 12 containing an antiviral agent on the surface of a substrate 11, similar to the antiviral laminate 10A. The undercoat coating layer 12 has a two-layer structure, and the layer 122 near the surface of the antiviral laminate 10C has a higher concentration of the antiviral agent than the layer 121 near the substrate 11 (see FIG. 1(c)). The undercoat coating layer 12 to which the antiviral agent is added can be a multi-layer structure of three or more layers, not limited to a two-layer structure. Even in this case, it is desirable that the layer closer to the surface of the antiviral laminate (hereinafter referred to as the laminate) has a higher concentration of the antiviral agent. This is because viruses adhere to the surface of the laminate, and the higher the concentration of the antiviral agent in the layer closer to the surface of the laminate, the more the antiviral agent can exhibit its antiviral performance. Furthermore, pinholes may occur in each layer, but in the case of such a multi-layer structure, the positions of the pinholes in each layer do not coincide, so that pinholes can be prevented as a whole antiviral multi-layer structure.

[0032] Here, the substrate 11 may be any article, but is preferably in sheet form when the laminate is used as a container material. In addition, from the viewpoints of transportability and coatability when applying the undercoat coating layer 12, the top coating layer 13, and the intermediate layer 14, the substrate 11 is preferably in sheet form with a thickness of 4.5 μm or more. More preferably, the substrate 11 is 12 μm or more.

[0033] For example, when the sheet-like substrate 11 is a material for forming a paper container, it may be a sheet containing paper in its layer structure. When the material is a material for forming a bag, it usually contains a resin in its layer structure. In addition, it may contain a metal or a metal compound. Examples of resins include polyester, polypropylene, polystyrene, nylon, polycarbonate, polyacrylonitrile, polyimide, etc. As metals, metal foils such as aluminum foils and metal vapor deposition films vapor-deposited on the resin film can be used. Examples of metal compounds include metal oxides such as silicon oxide and aluminum oxide, which can be used in the form of a metal oxide vapor deposition film vapor-deposited on the resin film. It is also possible to print or print on the substrate 11.

[0034] Next, the undercoat coating layer 12 containing an antiviral agent is a layer formed by coating a composition in which an antiviral agent is dispersed in a resin binder.

[0035] The antiviral agent is in the form of inorganic particles, and a portion of the particles must be exposed on the surface of the undercoat coating layer 12, to which the antiviral agent has been added, on the side of the overcoat coating layer 13.

[0036] As such a particulate antiviral agent, a metal or a compound thereof represented by the element symbol Ag, Cu, Sb, Ir, Ti, Ge, Sn, Tl, Pt, Pd, Bi, Au, Fe, Co, Ni, Zn, or In can be used.

[0037] The metal atoms contained in antiviral agents made of metals or metal compounds have a positive charge. There are viruses that are enveloped in a membrane containing lipids called an envelope, and viruses that do not have an envelope. The envelope of the enveloped virus is negatively charged, and the metal atoms attract and inactivate this envelope, thereby depriving the virus of its infectivity. In addition, active oxygen is generated by the metal or its compounds, and the action of this active oxygen can inactivate the virus and deprive it of its infectivity.

[0038] In addition, as described later, such metals or compounds thereof are stable even when an ultraviolet-curable resin binder is irradiated with ultraviolet light and cured, and therefore the antiviral layer 12 exhibits high antiviral performance even after ultraviolet light irradiation. In particular, in the case of the undercoat coating layer 12 using an ultraviolet-curable resin as a binder, the coating tends to harden before the coating surface is leveled because the coating rapidly hardens when exposed to ultraviolet light. This tends to result in a rougher surface than in the case of the hot air drying method or the hot roll drying method. Our experiments have shown that the increased surface area tends to further improve the antiviral effect.

[0039] Some of such particulate antiviral agents made of metals or their compounds are commercially available. For example, silver (Ag)-based antiviral agents include Biocide TB-B100 manufactured by Taisho Technos Co., Ltd., Novalon IV1000 manufactured by Toa Gosei Co., Ltd., W260 manufactured by DIC Corporation, Z253 Kokin AP10 manufactured by Toyo Ink Mfg. Co., Ltd., and PCT-NT ANV Additive manufactured by Dainichiseika Color & Chemicals Co., Ltd. In addition, copper (Cu)-based antiviral agents include NBC Meshtec Co., Ltd. and Cufitech Co., Ltd. In addition, zinc (Zn)-based antiviral agents include 3000D manufactured by Taisho Technos Co., Ltd.

[0040] Next, the resin binder that disperses the antiviral agent has the function of increasing the cohesiveness of the antiviral agent in the undercoat coating layer 12 to which the antiviral agent has been added, and also increasing the adhesion between the undercoat coating layer 12 to which the antiviral agent has been added and the substrate 11. The resin binder also improves the abrasion resistance of the undercoat coating layer 12 to which the antiviral agent has been added. Since the antiviral agent is fixed to the surface of the substrate 11 in this way to prevent it from falling off, the antiviral agent does not come off even when, for example, a finger or the like comes into contact with the surface, and the antiviral performance can be maintained for a long period of time. Since the antiviral performance can be maintained regardless of the presence or absence of contact with a finger or the like, a product container made of this laminate can prevent or suppress infection even when many people come into contact with it one after another.

[0041] In order to achieve the above-mentioned functions, it is desirable that at least the resin binder used in the undercoat coating layer 12 has ultraviolet curing properties. Such an ultraviolet curing resin binder can be formed by blending a photopolymerization initiator with a resin such as a polyester resin, a polyolefin resin, a polyamide resin, a polyurethane resin, or a polyacrylic resin.

[0042] The ultraviolet-curable resin binder is dissolved or dispersed in a suitable solvent, and an antiviral agent is mixed and dispersed therein to form a coating composition. This composition is then coated, dried, and cured by irradiation with ultraviolet light, thereby forming the undercoat coating layer 12 to which the antiviral agent has been added.

[0043] The amount of the antiviral agent is desirably 0.5% by mass or more relative to the solid content of the coating composition (the total amount of components remaining in the undercoat coating layer 12 to which the antiviral agent has been added after coating, drying, and curing), and more desirably 1.0% by mass or more.

[0044] The antiviral agent may be blended and dispersed by any known method, such as a dispersion method involving stirring with a propeller, a dispersion method using a homogenizer, or a dispersion method using a bead mill.

[0045] The coating method may be a known method, such as gravure coating, roll coating, or die coating.

[0046] In addition, ultraviolet irradiation methods are also known. For example, ultraviolet irradiation can be performed using a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, an LED lamp, or the like.

[0047] The top coating layer 13 containing no antiviral agent is necessary to prevent the antiviral agent consisting of inorganic particles exposed on the surface of the undercoat coating layer 12 from falling off and being scratched due to friction, without impairing the antiviral performance of the undercoat coating layer 12 thus formed. The top coating layer 13 is a layer formed by applying a composition in which no antiviral agent is dispersed in a resin binder.

[0048] Of the coating layers, at least the top coating layer 13 contains a slip agent such as micro wax, silicone oil, or resin beads.

[0049] The resin binder used in the topcoat coating layer 13 is also an ultraviolet-curable resin, for example, like the resin binder used in the undercoat coating layer 12, and the topcoat coating layer 13 is formed by applying a composition composed of the resin binder and then curing it by exposure to ultraviolet light.

[0050] As mentioned above, viruses contained in the body fluids of infected humans adhere to the surface of the laminate, so the thickness of the size coating layer 13 is an important factor.

[0051] The thickness of the top coat layer 13 is preferably 0.5 μm or more. If the thickness is less than 0.5 μm, local defects such as smudges occur in the coating film, and the surface of the antiviral agent exposed on the surface of the undercoat coat layer 12 to which the antiviral agent is added cannot be covered, and sufficient abrasion resistance is not exhibited. Furthermore, if the thickness is in the range of 0.5 μm to 5 μm, water molecules can sufficiently enter and exit through the mesh structure of the resin coating of the top coat layer 13, so that high antiviral performance equivalent to that when the undercoat coat layer 12 is exposed on the surface can be exhibited. Furthermore, if the thickness is more than 5 μm, water molecules cannot sufficiently enter and exit through the top coat layer 13, so that the antiviral performance is reduced. Furthermore, by making the thickness 5 μm or less, it is possible to exhibit the antiviral effect on the product surface without hindering the ionization of the metal components contained in the antiviral agent. Furthermore, as will be described next, when the undercoat coating layer 12 containing an antiviral agent is laminated directly on the substrate 11 having a rough surface, such as uncoated paper, the overcoat coating layer 13 desirably has a thickness of 1.0 μm or more to prevent pinholes.

[0052] That is, when a body fluid containing a liquid component (for example, sweat, saliva, sneeze, etc.) adheres to the surface of the laminate, if the substrate 11 is made of a water-absorbent material such as paper, the liquid component may pass through pinholes in the undercoat coating layer 12 to which an antiviral agent has been added and be absorbed by the substrate 11 that does not have antiviral properties. When the thickness of the undercoat coating layer 12 is 1 μm or more, there is little risk of pinholes being formed in the undercoat coating layer 12 to which an antiviral agent has been added, which is formed by applying the antiviral agent thickly, so that the liquid component adhered to the surface of the laminate can be prevented from passing through pinholes in the undercoat coating layer 12 to which an antiviral agent has been added and being absorbed by the substrate 11. For this reason, when the undercoat coating layer 12 having a single layer structure is directly laminated on the substrate 11 as in the laminate 10A according to the first specific example, the thickness of the undercoat coating layer 12 is preferably 1 μm or more. More preferably, it is 2.0 μm or more.

[0053] On the other hand, in the case of laminate 10B according to the second specific example, which is composed of four layers, namely, substrate 11, intermediate layer 14, undercoat coating layer 12 to which an antiviral agent has been added, and top coating layer 13 to which no antiviral agent has been added, pinholes may occur in both intermediate layer 14 and undercoat coating layer 12, but the positions of the pinholes in each layer 14, 12 do not coincide, so the thicknesses of intermediate layer 14 and undercoat coating layer 12 may both be less than 1.0 μm. For example, the thickness of undercoat coating layer 12 is 0.5 μm or more, and the sum of the thicknesses of undercoat coating layer 12, intermediate layer 14, and top coating layer 13 is 1.0 μm.

[0054] Also, even when the undercoat coating layer 12 containing the antiviral agent has a two-layer structure of the layer 121 close to the substrate 11 and the layer 122 close to the surface of the laminate 10C as in the laminate 10C according to the third specific example, the thickness of each of the layers 121 and 122 may be less than 1.0 μm, because the positions of the pinholes in the layers 121 and 122 do not coincide with each other.

[0055] Next, the intermediate layer 14 is placed between the substrate 11 and the undercoat layer 12 to which the antiviral agent is added. This intermediate layer 14 does not contain an antiviral agent and has the purpose of improving the adhesion between the substrate 11 and the undercoat coating layer 12, for example. In addition, when the substrate 11 is porous or has an uneven surface such as paper, the intermediate layer 14 can be provided as a filling layer for smoothing the surface.

[0056] The intermediate layer 14 may be, for example, a pattern ink layer, or may be formed by applying various adhesives, such as a two-liquid curing dry lamination adhesive made of a polyol and an isocyanate.

[0057] Alternatively, the intermediate layer 14 may be formed by melt extrusion coating a thermoplastic resin, or by dissolving or dispersing a thermoplastic resin in a solvent and coating the layer. When the intermediate layer 14 is formed from a thermoplastic resin, it is desirable that the thermoplastic resin of the intermediate layer 14 and the resin binder in the undercoat coating layer 12 are the same type of resin in order to improve the adhesion between the intermediate layer 14 and the undercoat coating layer 12 to which the antiviral agent has been added. For example, if the resin binder in the undercoat coating layer 12 is a polyester-based resin, the thermoplastic resin constituting the intermediate layer 14 is also a polyester-based resin. The intermediate layer 14 may also be formed by coating with a water-based or solvent-free system.

[0058] This intermediate layer 14 can also be formed by coating using a known method. When the intermediate layer 14 is made of an ultraviolet curable resin, it is preferable to coat and dry the ultraviolet curable resin that constitutes the intermediate layer 14, then coat and dry the coating compositions for the undercoat coating layer 12 and the top coat coating layer 13, and then irradiate them with ultraviolet light to cure the intermediate layer 14, the undercoat coating layer 12, and the top coat coating layer 13 all at once.

[0059] The intermediate layer 14 may have any thickness, which may be determined depending on the purpose.

[0060] A pre-formed film may be used as the intermediate layer 14. In this case, the film may be adhered to the substrate 11 to form the intermediate layer 14. The adhesion method and thickness may be arbitrary.

[0061] As described above, this laminate can be used as a material for forming a container. For example, it can be a paper container or a packaging bag. It may also be deep-drawn into a container. In any case, it is desirable to dispose a coating layer having an undercoat coating layer 12 containing the antiviral agent and an overcoat coating layer 13 not containing the antiviral agent on the outer surface of the container, which is likely to come into contact with hands and fingers. EXAMPLES

[0062] The present invention will be described below with reference to examples and comparative examples.

[0063] In Examples 1, 2, and 3 and Comparative Example 1, the substrate 11 had a basis weight of 270 g / m 2 Coated paper (Maricoat, manufactured by Hokuetsu Paper Sales Co., Ltd.) was used. In Example 4 and Comparative Example 2, a polyester film (E5104, manufactured by Toyobo Co., Ltd.) having a thickness of 12 μm was used as the substrate 11.

[0064] As the resin binder constituting the undercoat coating layer 12 or the topcoat coating layer 13, ACE OP varnish manufactured by Toyo Ink Mfg. Co., Ltd. was prepared in Examples 1, 2, and 3 and Comparative Example 1. In Example 4 and Comparative Example 2, UC Clear W480E Gloss UVH-3 manufactured by DIC Graphics Corporation was prepared.

[0065] As an antiviral agent, a particulate silver (Ag)-based antiviral agent (Taisho Co., Ltd.) We prepared Biocide TB-B100 (manufactured by Technos).

[0066] 2(a)-(c) are cross-sectional views showing sheets of comparative examples, and the cross-sectional view showing the sheet of Comparative Example 1 related to the evaluation below is shown in Fig. 2(b) as described later, and the cross-sectional view showing the sheet of Comparative Example 2 is shown in Fig. 2(a) as described later. Fig. 2(c) is not related to the evaluation below, but is shown as a comparative example for the third specific example of Fig. 1(c).

[0067] Example 1 This example is a laminate 10B according to a second specific example, which is composed of four layers: a substrate 11, an intermediate layer 14, an undercoat coating layer 12, and an overcoat coating layer 13, as shown in FIG. 1(b).

[0068] That is, after applying a pattern ink layer as the intermediate layer 14 to the surface of the substrate 11, a coating composition obtained by mixing the varnish and the antiviral agent was applied to the surface of the intermediate layer 14 and cured by ultraviolet irradiation to form the undercoat coating layer 12. The antiviral agent contained in the undercoat coating layer 12 thus formed was 10% by mass of the undercoat coating layer 12. The thickness of the undercoat coating layer 12 was 1.0 μm. Furthermore, a coating composition obtained by additionally adding and mixing 3% by mass of a slip agent to the varnish was applied to the surface of the undercoat coating layer 12 to a coating thickness of 1.0 μm and cured by ultraviolet irradiation to form the overcoat coating layer 13.

[0069] Example 2 This example has the same structure as Example 1, except that the coating thickness of the size coating layer 13 is 5.0 μm.

[0070] Example 3 This example is also a laminate 10B according to a second specific example, and is composed of four layers, namely, a substrate 11, an intermediate layer 14, an undercoat coating layer 12, and an overcoat coating layer 13, as shown in FIG. 1(b).

[0071] The intermediate layer 14 was formed from the same resin binder as that constituting the undercoat coating layer 12 and the overcoat coating layer 13. That is, ACE OP varnish manufactured by Toyo Ink Mfg. Co., Ltd. was applied to the surface of the substrate 11 and dried without mixing with an antiviral agent or slip agent.

[0072] The lamination was carried out in the same manner as in Example 1, except that the varnish was applied as the intermediate layer 14 . The intermediate layer 14 has a thickness of 1.0 μm.

[0073] Example 4 This example is a laminate 10A according to a first specific example, which is composed of three layers: a substrate 11, an undercoat coating layer 12, and an overcoat coating layer 13, as shown in FIG. 1(a).

[0074] That is, an undercoat coating layer 12 was formed by applying a coating composition obtained by mixing the varnish and the antiviral agent to the surface of the substrate 11. The antiviral agent contained in the undercoat coating layer 12 thus formed was 7% by mass of the undercoat coating layer 12. The thickness of the undercoat coating layer 12 was 2.0 μm. Furthermore, a coating composition obtained by further adding and mixing 2% by mass of a slip agent into the varnish was applied to the surface of the undercoat coating layer 12 to a coating thickness of 3.0 μm, and cured by irradiation with ultraviolet light to form an overcoat coating layer 13.

[0075] Comparative Example 1 In this example, as shown in FIG. 2(b), a top coat layer 13 is not provided, and the top coat layer 13 is not provided. An intermediate layer 14 and a coating layer 12 containing an antiviral agent (the same layer as the undercoat coating layer in Example 1) were provided on the sheet 20B. The rest of the sheet was produced by the same method as in Example 1.

[0076] Comparative Example 2 2(a), this example is a sheet 20A in which only a coating layer 12 containing an antiviral agent (the same layer as the undercoat coating layer in Example 4) is provided on a substrate 11 without providing an intermediate layer 14. The rest of the example was produced by the same method as in Example 4.

[0077] (evaluation) The laminates of Examples 1 to 4 and the sheets of Comparative Examples 1 and 2 were evaluated from three standpoints: abrasion resistance and antiviral performance.

[0078] (Method of evaluating wear resistance) Abrasion resistance was evaluated according to JIS P8136, a method for testing the abrasion resistance of paperboard. A 25mm-wide sample was placed on a sliding table with the coated side facing up, and a 20mm-wide sample was attached to the surface of a 500g weight so that the sample placed on the sliding table and the coated side would rub against each other. After 100 reciprocating strokes over a friction distance of 120mm, if powder generation or scratches on the coated surface were easily visible, it was rated as ×, and if no powder generation or scratches were easily visible, it was rated as ◯.

[0079] (Method for evaluating antiviral activity) Antiviral tests were conducted in accordance with ISO 21702:2019. After the abrasion resistance evaluation, the sample was placed in a sterile petri dish, and 0.4 mL of virus fluid was inoculated onto the sample. The virus fluid used at this time contained an enveloped virus (influenza virus). The sample was then covered with a 40 mm square polyethylene film. After the dish was covered, the sample and virus were inoculated under conditions of 25°C and humidity of 90% or higher. After a specified time, 10 mL of SCDLP medium was poured into the petri dish to wash out the virus. The virus infectivity of the washed-out liquid was measured using the plaque method.

[0080] (Measurement of viral infectivity (plaque method)) The host cells were cultured in a monolayer on a 6-well plate, and 0.1 mL of serially diluted washout solution was inoculated into each well. After culturing for 1 hour under 5% CO2 and 37°C conditions to allow the virus to adsorb onto the cells, agar medium was poured into the 6-well plate and cultured for an additional 2-3 days. After culturing, the cells were fixed and stained, and the number of plaques formed was counted.

[0081] (Calculation of viral infectivity) According to the following formula, 1 cm of sample 2 The viral infectivity per unit was calculated. V = (10 × C × D × N) / A V: Viral infectivity per 1 cm2 of sample (PFU / cm 2 ) C: Number of plaques counted D: Dilution ratio of the well in which the plaques were counted N: SCDLP amount A: Contact area between the sample and the virus (area of ​​the polyethylene film)

[0082] <Calculation of antiviral activity value> The antiviral activity value was calculated according to the following formula. Antiviral activity value = Log(Vb) - Log(Vc) Log(Vb): Common logarithm of the virus infectivity per 1 cm2 of the untreated sample after 24 hours Log(Vc): Common logarithm of the virus infectivity per 1 cm2 of the antiviral treated sample after 24 hours The calculated antiviral activity value was evaluated using the following criteria: ◯, ×. <Evaluation criteria> ○: Antiviral activity value is 2Log10 or higher ×: Antiviral activity value is less than 2 Log10

[0083] (Evaluation results and considerations) The evaluation results of abrasion resistance and antiviral performance are shown in Table 1.

[0084] [Table 1]

[0085] From these results, it can be seen that when the size coating layer 13 was not laminated (Comparative Examples 1 and 2), the abrasion resistance was poor, and the antiviral performance was also poor on the surface after the abrasion resistance test.

[0086] In contrast, Examples 1, 2, 3, and 4, which have the size coating layer 13 laminated thereon, exhibit excellent abrasion resistance and antiviral performance, maintain the quality of the product surface, and maintain excellent antiviral performance. Since the effect was confirmed with paper substrates and film substrates, the embodiment of the present invention can be used in a wide range of applications, from container packaging such as paper containers, cardboard, and soft packaging materials to books, securities, cards, and other products. [Explanation of symbols]

[0087] 10A, 10B, 10C: Antiviral laminate 11: Base material 12: Undercoat coating layer 121: Layer close to the substrate 122: Layer close to the surface of the laminate 13: Top coat layer 14: Intermediate layer

Claims

1. An anti-viral laminate comprising a coating layer having anti-viral properties formed on the surface of a substrate, an anti-viral laminate comprising: from the substrate side; an intermediate layer; an undercoat coating layer; and a top coating layer having a thickness of 0.5 μm or more and 5 μm or less; the undercoat coating layer is a layer coated with a composition in which an antiviral agent is dispersed in a resin binder, the antiviral agent being inorganic particles; the top coating layer is a layer coated with a composition in which the antiviral agent is not dispersed in a resin binder; and the intermediate layer and the resin binder of the undercoat coating layer are made of a polyester-based resin.

2. 2. The anti-viral laminate according to claim 1, wherein the substrate is made of paper, resin, metal, a metal compound, or a laminate thereof.

3. 3. The anti-viral laminate according to claim 1, wherein at least the top coating layer of the coating layers contains a slip agent such as micro wax, silicone oil, or resin beads.

4. The anti-viral laminate according to any one of claims 1 to 3, characterized in that the anti-viral agent is composed of a metal represented by the atomic symbol Ag, Cu, Sb, Ir, Ti, Ge, Sn, Tl, Pt, Pd, Bi, Au, Fe, Co, Ni, Zn, or In, or a compound thereof.

5. An anti-viral container comprising an anti-viral laminate according to any one of claims 1 to 4, wherein the coating layer is disposed on the outer surface of the container.

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