JP7830066B2 - Antiviral films and food packaging bags - Google Patents

Description

This invention relates to an antiviral film and a food packaging bag using the antiviral film.

For example, the history of coronavirus-induced infections is long, with MERS and SARS viruses being well-known in recent years. Viral infections develop when viruses enter the body through the mouth, nose, eyes, etc. The main routes of viral transmission are contact transmission, droplet transmission, and airborne transmission. Research and development of antiviral agents that exhibit antiviral effects are being conducted against viral infections, and antiviral agents consisting of specific metal elements and organic compounds are currently on the market. These antiviral agents are suitably used, for example, in products in various fields such as building materials, bedding, paints, and clothing, as a measure against contact transmission.

Currently, COVID-19 is a global pandemic, with numerous cases being confirmed daily in Japan, and deaths due to the infection being reported. The spread of COVID-19 has heightened awareness of infection prevention, and there is a growing demand for safety, security, and hygiene when purchasing goods in stores.

For example, in stores such as supermarkets and convenience stores, customers often return items they have picked up to the shelves, meaning that many different people touch the same products. This increased contact by multiple people is a growing concern from a hygiene standpoint, as it increases the risk of contact transmission. Therefore, it is believed that imbuing packaging bags for various products, such as food and daily necessities, with antiviral properties—that is, imbuing the film material used in packaging bags with antiviral properties—can help address the issue of contact transmission described above.

Examples of film-like materials with antiviral properties include those in which an antiviral agent is applied to the film surface to impart antiviral properties. However, there have been quality issues, such as uneven application of the antiviral agent.

Furthermore, another type of antiviral film is known in which metal particles, consisting of at least one metal (Cu and Pd) with antiviral properties, are scattered in an island-like pattern on a base film (see Patent Document 1). In this conventional antiviral film, the metal particles are attached to the film by a spraying process or a transfer process such as an inkjet method to impart the antiviral effect. This antiviral film can be suitably used as a protective film for touch panels, a film for displays, and other surfaces that are frequently touched by people.

However, this antiviral film is economically expensive due to the complex processing required to maintain its antiviral properties, making it unsuitable for general-purpose use such as packaging bags for food and daily necessities. In particular, there is a need for food packaging bags that adequately address contact transmission in antiviral products.

Japanese Patent Publication No. 2018-134753

This invention has been made in view of the above points, and provides an antiviral film that can be manufactured efficiently, economically, and with stable quality, and is suitable for general use. It also provides a food packaging bag that adequately addresses contact transmission.

In other words, the invention of claim 1 relates to an antiviral film comprising two or more layers including a base layer and an antiviral layer, having antiviral performance with an antiviral activity value of 2.0 or higher against at least one of influenza virus or feline calicivirus in accordance with ISO 21702 (2019), wherein the antiviral layer is provided on the surface of the film with a thickness of 1.0 to 2.0 μm to which 1% by weight or more of a soluble glass antiviral agent containing silver and copper components is added, and the haze value of the film is 7% or less.

The invention of claim 2 relates to the antiviral film according to claim 1, wherein the antiviral agent content in the antiviral layer is 3 to 6% by weight.

The invention of claim 3 relates to the antiviral film according to claim 1 or 2 , wherein the film body is a food packaging film.

The invention of claim 4 relates to a food packaging bag characterized by being composed of the antiviral film described in claim 3 .

The antiviral film according to claim 1 is composed of two or more layers including a base layer and an antiviral layer, and is a film having antiviral performance with an antiviral activity value of 2.0 or higher against at least one of influenza virus or feline calicivirus in accordance with ISO 21702 (2019), wherein the antiviral layer is provided on the surface of the film with a thickness of 1.0 to 2.0 μm to which 1% by weight or more of a soluble glass antiviral agent containing silver and copper components is added, and the haze value of the film is 7% or less, so that it can be manufactured more efficiently and at a lower cost than conventional methods, the quality can be stabilized, and an antiviral film suitable for general use can be provided, and in particular it is suitable for packaging food and the like as a transparent film.

According to the antiviral film of claim 2, in the invention of claim 1, the content of the antiviral agent in the antiviral layer is 3 to 6% by weight, thus ensuring appropriate antiviral performance.

According to the antiviral film of claim 3 , in the invention of claim 1 or 2 , since the film body is a food packaging film, it is possible to manufacture a packaging bag with a structure suitable for food packaging.

According to the food packaging bag of claim 4 , since it is made of the antiviral film described in claim 3 , it is possible to provide a food packaging bag with a structure that effectively addresses contact infection.

This is a schematic cross-sectional view of an antiviral film according to one embodiment of the present invention. Figure 1 is a schematic cross-sectional view of a food packaging bag using the antiviral film.

The antiviral film 10 according to one embodiment of the present invention shown in Figure 1 is a film body having antiviral performance with an antiviral activity value of 2.0 or higher, and is composed of two or more layers including a base layer 20 and an antiviral layer 30. This antiviral film 10 is used in various film products such as packaging bags, and is particularly suitable as a film material for packaging bags used in stores such as supermarkets and convenience stores for items such as bread, rice balls, fresh foods, processed foods, confectionery, and daily necessities.

In antiviral film 10, the antiviral activity value is a standard for determining the antiviral performance of an antiviral processed product. The antiviral activity value of non-textile antiviral processed products such as plastic and ceramic products is calculated using an antiviral test method compliant with ISO 21702 (2019). According to the Society of International Antimicrobial Agents (SIAA), the antiviral performance of antiviral film 10 is based on the requirement that the antiviral activity value of the antiviral processed product be 2.0 or higher. Specifically, this antiviral activity value is the value against at least one of either influenza virus or feline calicivirus. That is, if the antiviral activity value is 2.0 or higher against either influenza virus or feline calicivirus, the product is recognized as an antiviral processed product. When the antiviral activity value is 2.0 or higher, the virus removal rate is 99% or higher.

The base layer 20 is the main resin layer of the film 10. This base layer 20 is composed of a suitable resin material suitable for use in food packaging and the like. For example, polyolefin resins are preferably used, and polypropylene resins, which are inexpensive and highly versatile, are particularly preferred. Polypropylene resins are selected from polymers mainly composed of propylene, such as homopolypropylene (a homopolymer of propylene) or copolymers of propylene with other olefins such as ethylene or butene (propylene copolymers).

The antiviral layer 30 is a resin layer that imparts antiviral properties to the film 10, and is provided on the surface layer of the film body with an antiviral agent added at a concentration of 1% by weight or more. The surface layer of the film body is the outermost layer of the antiviral film 10, corresponding to the surface layer and the back layer. In the example shown in Figure 1, the antiviral layer 30 is formed only on the surface layer of one side of the base layer 20, i.e., on one surface (surface layer) of the film 10. The antiviral layer 30 is composed of a suitable resin material suitable for use in food packaging, etc., and from the viewpoint of adhesive strength with the base layer 20, it is preferable, for example, to mainly consist of the same type of resin material as the base layer 20.

The antiviral agent is an additive that imparts antiviral properties and consists of soluble glass containing silver and copper components with antiviral effects. The antiviral performance imparted by the antiviral agent is enhanced according to its content relative to the resin material constituting the antiviral layer 30; a content of 1% by weight or more is sufficient to obtain the required antiviral performance. However, if the antiviral agent content is too high, the transparency of the film 10 tends to deteriorate (the haze value increases). Furthermore, since the antiviral agent contains metal components, a high content relative to the resin material may lead to a phenomenon called copper damage, where the oxidative degradation of the resin is accelerated. While copper damage can be suppressed by additives, these additives are expensive and may reduce transparency. Therefore, to ensure appropriate antiviral performance, the antiviral agent content in the antiviral layer 30 is preferably 3 to 6% by weight.

In the antiviral layer 30, as shown in Figure 1, the antiviral effect is exerted by the appropriate exposure of the antiviral agent 35 from the layer surface 31. In this embodiment, since the antiviral agent 35 has a particle size of approximately 2.5 μm, it is preferable that the antiviral layer 30 be formed with a thickness of 1.0 to 2.0 μm to ensure adequate antiviral performance. If the thickness of the antiviral layer 30 is less than 1.0 μm, the antiviral agent 35 may detach from the antiviral layer 30. If it is thicker than 2.0 μm, a large amount of antiviral agent 35 may not be exposed from the layer surface 31, potentially resulting in insufficient antiviral effect.

In this antiviral film 10, in addition to the base layer 20 and the antiviral layer 30, an appropriate resin layer may be formed as needed. The other resin layer is composed of an appropriate resin material suitable for use in food packaging, etc. From the viewpoint of adhesive strength with the base layer 20, it is preferable, for example, to mainly consist of the same type of resin material as the base layer 20. The other resin layer is formed between the base layer 20 and the surface layer (outermost layer) antiviral layer 30, or on the other side (back side) if the antiviral layer 30 is only on one side (front side). Furthermore, depending on the application, multiple layers of the other resin layer may be formed, or they may be formed on both sides of the base layer 20. In the illustrated film 10, the back layer 40 is formed on the other side of the base layer 20.

The above-mentioned film 10 is formed by melting the resins constituting each layer and using known manufacturing techniques such as the T-die method or the inflation method to create a film of a predetermined thickness. Furthermore, when polypropylene resins are used for the base layer 20 and the antiviral layer 30, it is preferable to manufacture the film using a known uniaxial stretching or biaxial stretching method. The stretched polypropylene film has excellent transparency and high mechanical strength, resulting in superior printability and bag-making properties, making it suitable as a food packaging film.

Furthermore, in film 10, known additives such as antifogging agents, antistatic agents, antioxidants, light stabilizers, lubricants, and antiblocking agents may be appropriately added to one or more layers of each layer as needed. When used as a food packaging film, it is preferable to add antifogging agents and antiblocking agents. As antifogging agents, one or more types of alkyldiethanolamine, alkyldiethanolamine fatty acid esters, glycerin fatty acid esters, etc., used in known antifogging films, are used, with a particularly preferred mixture of the three listed antifogging agents. As antiblocking agents, one or more types of known inorganic silica or organic cross-linked acrylic beads are used.

In the film 10, it is preferable to have high transparency to obtain a good appearance. Transparency is evaluated, for example, by the level of the haze value. The haze value is an indicator of the film's cloudiness and is measured in accordance with JIS K 7136 (2000). The lower the value, the higher the transparency. Therefore, it is preferable that the haze value of the film 10 be 7% or less. When the haze value of the film 10 is 7% or less, a transparent film can be made, which is particularly suitable for packaging food and the like. If the haze value exceeds 7%, the transparency of the film itself is lost, and there is a risk that the visibility required, especially for packaging food and the like, will be impaired.

Furthermore, the film 10 may be subjected to corona treatment on its surface as needed. The wetting tension of the film surface after corona treatment is preferably 36 mN/m to 44 mN/m. If the wetting tension is less than 36 mN/m, the anti-fogging properties may be insufficient, or the adhesion of printing inks may be poor when printing is performed. If it exceeds 44 mN/m, the bleed-out of the anti-fogging agent to the surface may increase, potentially causing whitening or blocking of the film.

The antiviral film 10 of the present invention, by adding an antiviral agent to a resin material to form the antiviral layer 30, can be manufactured more efficiently and at a lower cost than conventional antiviral films, such as those in which an antiviral agent is applied to the film surface, and can also stabilize quality by avoiding uneven coating. Furthermore, if the antiviral layer 30 is formed only on one side of the substrate layer 20, i.e., on one side (front side) of the film 10, the film 10 is configured so that antiviral performance is imparted to one side (front side) and the other side (back side) has other functions, making it suitable for a variety of applications and providing an antiviral film suitable for general use. Alternatively, if the antiviral layer 30 is formed on both sides of the film 10, antiviral performance can be imparted to both sides of the film 10.

In particular, the antiviral film 10 of the present invention is suitable for food packaging when antiviral properties are applied to only one side (the surface side). That is, as shown in the food packaging bag 50 in Figure 2, the inner surface 51, which comes into contact with the contents (food) C, is not treated with antiviral properties, while the outer surface 52, which does not come into contact with the contents C but is touched by human hands, etc., is treated with antiviral properties. In the illustrated embodiment, the inner surface 51 of the packaging bag 50 corresponds to the back layer 40 of the film 10, and the outer surface 52 corresponds to the antiviral layer 30 of the film 10.

This food packaging bag 50 can be given antiviral properties to the entire outer surface 52 that may come into contact with human hands, etc. Therefore, it can be constructed to be extremely effective in preventing contact transmission. The food packaging bag 50 is used to package the contents C of food, etc., using known packaging methods such as pillow packaging or three-side seal packaging.

[Preparation of antiviral films]
For prototypes 1 to 10, based on the resin blending ratio (weight %) described later, resin pellets and other raw materials were supplied to an extruder for melting and kneading. The films were then co-extruded using a T-die film molding machine that co-extrudes three layers at once, and a biaxial stretcher was used to produce films with a stretch ratio of 5 times in the longitudinal direction (winding direction, MD) and 8 times in the transverse direction (axial direction, TD). After film formation, both surface layers were subjected to corona treatment under conditions commonly used for films. Each of prototypes 1 to 10 consists of three layers: a base layer, a surface layer formed on one side (front side) of the base layer, and a back layer formed on the other side (back side) of the base layer. The antiviral agent was added to the surface layer.

[Resin materials]
Each layer constituting the film was made using one of the following resins (PP1) to (PP6).
• Resin PP1: Homopolypropylene resin (manufactured by Nippon Polypropylene Co., Ltd., "FL203D")
- Resin PP2: An anti-fogging masterbatch made by melt-kneading 8% by weight of an anti-fogging agent consisting of 40% by weight of glycerin monostearate, 20% by weight of oleyl diethanolamine, and 40% by weight of stearyl diethanolamine monostearate, with 92% by weight of Resin PP1. - Resin PP3: Random polypropylene resin (manufactured by Nippon Polypropylene Co., Ltd., "FX4E")
- Resin PP4: A masterbatch made by melting and kneading 90% by weight of resin PP3 and 10% by weight of soluble glass containing silver and copper components (manufactured by Ishizuka Glass Co., Ltd., "GlassAC01"). - Resin PP5: A masterbatch made by melting and kneading 90% by weight of resin PP3 and 10% by weight of soluble glass containing silver components (manufactured by Ishizuka Glass Co., Ltd., "Ion Pure WPA"). - Resin PP6: A masterbatch made by melting and kneading 90% by weight of resin PP3 and 10% by weight of soluble glass containing silver components (manufactured by Ishizuka Glass Co., Ltd., "Ion Pure ZAF HS").

[Prototype Example 1]
Prototype 1 is a biaxially oriented film with a thickness of approximately 20 μm, composed of a base layer extruded at 240°C using resin PP1, a surface layer extruded at 200°C from a mixture of resin PP3 and resin PP4 in a ratio of 50% by weight, and a back layer extruded at 240°C using resin PP1. In the film of Prototype 1, the extrusion amounts of each raw material were adjusted so that the thickness of each layer was in the ratio of surface layer/base layer/back layer to 2/17/1. In addition, the total amount of soluble glass in the surface layer of the film of Prototype 1 is 5.0% by weight.

[Prototype Example 2]
Prototype Example 2 is a biaxially oriented film with a thickness of approximately 20 μm, constructed in the same manner as Prototype Example 1, except that the base layer is composed of a mixture of resin PP1 at a ratio of 87.5% by weight and resin PP2 at a ratio of 12.5% by weight. In the film of Prototype Example 2, the total amount of soluble glass in the surface layer is 5.0% by weight. In addition, the total amount of antifogging agent in the base layer is 1.0% by weight.

[Prototype Example 3]
Prototype Example 3 is a biaxially oriented film with a thickness of approximately 20 μm, composed of a base layer extruded at 240°C using resin PP1, a surface layer extruded at 200°C using resin PP3, and a back layer extruded at 240°C using resin PP1. In the film of Prototype Example 3, the extrusion amounts of each raw material were adjusted so that the thickness of each layer was in the ratio of surface layer/base layer/back layer of 1/18/1.

[Prototype Example 4]
Prototype Example 4 is a biaxially oriented film with a thickness of approximately 20 μm, composed of a base layer extruded at 240°C using resin PP1, a surface layer extruded at 200°C from a mixture of resin PP3 and resin PP5 in a ratio of 50% by weight, and a back layer extruded at 240°C using resin PP1. In the film of Prototype Example 4, the extrusion amounts of each raw material were adjusted so that the thickness of each layer was in the ratio of surface layer/base layer/back layer of 1/18/1. In addition, the total amount of soluble glass in the surface layer of the film of Prototype Example 4 is 5.0% by weight.

[Prototype Example 5]
Prototype 5 is a biaxially oriented film with a thickness of approximately 20 μm, constructed in the same manner as Prototype 2, except that the base layer is made of resin PP1 and the surface layer is made of a mixture of resin PP3 and resin PP6 in a ratio of 50% by weight. In the film of Prototype 5, the total amount of soluble glass in the surface layer is 5.0% by weight.

[Prototype Example 6]
Prototype 6 is a biaxially oriented film with a thickness of approximately 20 μm, constructed in the same manner as Prototype 3, except that the base layer is composed of a mixture of resin PP1 at a ratio of 53.8% by weight and resin PP2 at a ratio of 46.2% by weight. In the film of Prototype 6, the total amount of antifogging agent in the base layer is 3.7% by weight.

[Prototype Example 7]
Prototype 7 is a biaxially oriented film with a thickness of approximately 20 μm, constructed in the same manner as Prototype 3, except that the base layer is made of resin PP1 and the surface layer is made of a mixture of resin PP3 at a ratio of 90% by weight and resin PP4 at a ratio of 10% by weight. In the film of Prototype 7, the total amount of soluble glass in the surface layer is 1.0% by weight.

[Prototype Example 8]
Prototype 8 is a biaxially oriented film with a thickness of approximately 20 μm, constructed in the same manner as Prototype 3, except that the base layer is made of resin PP1 and the surface layer is made of a mixture of resin PP3 at a ratio of 70% by weight and resin PP4 at a ratio of 30% by weight. In the film of Prototype 8, the total amount of soluble glass in the surface layer is 3.0% by weight.

[Prototype Example 9]
Prototype 9 is a biaxially oriented film with a thickness of approximately 20 μm, constructed in the same manner as Prototype 3, except that the base layer is made of resin PP1 and the surface layer is made of a mixture of resin PP3 and resin PP4 in a ratio of 50% by weight. In the film of Prototype 9, the total amount of soluble glass in the surface layer is 5.0% by weight.

[Prototype Example 10]
Prototype 10 is a biaxially oriented film with a thickness of approximately 20 μm, constructed in the same manner as Prototype 3, except that the base layer is made of resin PP1 and the surface layer is made of a mixture of resin PP3 at a ratio of 30% by weight and resin PP4 at a ratio of 70% by weight. In the film of Prototype 10, the total amount of soluble glass in the surface layer is 7.0% by weight.

[Evaluation of the performance of antiviral films]
Using prototype films 1 to 10, the film thickness (μm), haze (%), and antiviral activity value were measured and their performance was evaluated. In the overall performance evaluation of the antiviral film, if the antiviral activity value was judged to be "unacceptable," it was marked as "unacceptable (×)," and if the antiviral activity value was judged to be "acceptable" or higher, it was marked as "acceptable (〇)" or higher. In particular, if both the antiviral activity value and haze were judged to be "good," it was marked as "good (◎)." The results are shown in Tables 1 and 2 below. Tables 1 and 2 also include the total amount (weight %) of soluble glass contained in the surface layer and the metal component.

[Measuring the thickness of the film]
The overall thickness of each film from prototype examples 1 to 10 was measured in accordance with JIS K 7130 (1999).

[Measurement of haze]
Haze (%) measurement is an indicator of transparency and was performed in accordance with JIS K 7136 (2000) using a haze meter (NDH-5000, manufactured by Nippon Denshoku Industries Co., Ltd.). For prototype examples 1 to 10, since the films are intended for food packaging and require transparency that allows the contents to be visible when food is packaged, a measurement result of 7% or less was rated as "Good (○)" and a result greater than 7% was rated as "Unacceptable (×)".

[Measurement of antiviral activity levels]
The antiviral activity value is calculated using an antiviral test method compliant with ISO 21702 (2019). The antiviral test method involves first inoculating a 50 mm x 50 mm test piece with 0.4 ml of a pre-prepared virus suspension, covering it with a 40 mm x 40 mm cover film, and allowing it to stand at 25°C and 90% RH or higher for 24 hours to allow the virus and sample to react. Subsequently, 10 ml of wash solution (SCDLP medium) is added to recover the virus from the sample, and the recovered virus is cultured to measure the viral infectivity titer. This antiviral test allows the use of one or more viruses, including influenza A virus and feline calicivirus. Influenza A virus is an enveloped type of virus, and the novel coronavirus also belongs to this type. Feline calicivirus is a non-enveloped type of virus and is a surrogate virus for norovirus. In the examples, influenza A virus (H3N2) and feline calicivirus (F-9) were used.

The viral infectivity titer (PFU/ ^cm² ) is determined by measuring the number of plaques in Well's dilution series, where 6 to 60 plaques appear after viral culture, and using the following formula.
Viral titer/0.1 ml (PFU/0.1 ml) = number of plaques × dilution factor Viral titer/ml (PFU/ml) = number of plaques × dilution factor × 10
Viral infectivity titer / 1 ^cm² (PFU/ ^cm² )
= (Viral infectivity titer/ml) × (Washing solution volume) ÷ (Cover film area)

Based on the measured viral infectivity titer, the antiviral activity value is calculated using the following formula. Then, based on the criteria established by SIAA, if the antiviral activity value calculated using the following formula is 2.0 or higher for both influenza virus and feline calicivirus, it is classified as "Good (◎)", if either influenza virus or feline calicivirus is 2.0 or higher, it is classified as "Acceptable (〇)", and if both influenza virus and feline calicivirus are less than 2.0, it is classified as "Unacceptable (×)".
R = Ut - At
R: Antiviral activity value Ut: Mean of the common logarithm of the viral infectivity titer (PFU/ ^cm² ) of the untreated product after 24 hours of standing At: Mean of the common logarithm of the viral infectivity titer (PFU/ ^cm² ) of the antiviral treated product after 24 hours of standing

[Results and Discussion]
As shown in Table 1, the overall evaluations were "Good (◎)" for prototypes 1, 2, 8, and 9, "Acceptable (〇)" for prototypes 7 and 10, and "Unacceptable (×)" for prototypes 3 to 6. Of the films in prototypes 3 to 6 that received an overall evaluation of "Unacceptable," the film in prototype 3 had a surface layer that did not contain an antiviral agent (soluble glass), and the films in prototypes 4 and 5 used soluble glass with only silver as the metal component as the antiviral agent in the surface layer, resulting in extremely low antiviral activity values for all of them. The film in prototype 6 was a film with an excessive amount of antifogging agent added to the base layer. It was expected that antiviral performance would be exhibited by excessively bleeding out the antifogging agent to the film surface, but no antiviral effect was obtained at all.

In contrast, prototype examples 1, 2, 8, and 9, which received an overall evaluation of "Good," used soluble glass containing silver and copper components as antiviral agents in the surface layer. This indicates that soluble glass containing silver and copper components is preferable as an antiviral agent added to the surface layer.

Regarding the film of prototype example 10, which received an overall evaluation of "acceptable," the surface layer uses soluble glass with silver and copper metal components as antiviral agents. It was found to have high antiviral activity and a good antiviral effect. However, the film of prototype example 10 had a high haze value, resulting in slightly reduced transparency. Therefore, the film of prototype example 10 is not very suitable for use as a transparent film, but it can be used well as an antiviral film when transparency is not required. The film of prototype example 7, which also received an overall evaluation of "acceptable," has slightly insufficient antiviral activity against influenza virus, but its antiviral activity against feline calicivirus exceeds the standard value, making it suitable for use as an antiviral film.

Furthermore, of the two prototype films, Prototype 1 and 2, which received an overall evaluation of "Good," Prototype 2 is a film in which an antifogging agent was added to the base layer. This Prototype 2 film achieved the same antiviral activity value as Prototype 1, which did not have an antifogging agent added. Although it was thought that the antifogging agent might hinder the antiviral effect due to its tendency to rise to the surface of the film, as can be seen from Prototypes 1 and 2, it was demonstrated that appropriate antiviral performance can be obtained even when an appropriate amount of antifogging agent is added.

The antiviral film of the present invention has an antiviral layer formed on the surface of the film body by adding an antiviral agent of soluble glass containing silver and copper components. Therefore, it can be manufactured more efficiently and at a lower cost than conventional methods, while maintaining stable quality. Furthermore, this antiviral film is suitable for general use, and in particular, when used as a food packaging film, it can provide food packaging bags with a structure that effectively prevents contact transmission.

10 Antiviral film 20 Base layer 30 Antiviral layer 31 Layer surface 35 Antiviral agent 40 Back layer 50 Food packaging bag 51 Inside of food packaging bag 52 Outside of food packaging bag C Contents

Claims (4)

A film comprising two or more layers including a base layer and an antiviral layer, having antiviral performance with an antiviral activity value of 2.0 or higher against at least one of influenza virus or feline calicivirus in accordance with ISO 21702 (2019),
The antiviral film is characterized in that the antiviral layer is provided on the surface of the film body to a thickness of 1.0 to 2.0 μm with an antiviral agent of soluble glass containing silver and copper components added in an amount of 1% by weight or more, and the haze value of the film body is 7% or less. The antiviral film according to claim 1, wherein the antiviral agent content in the antiviral layer is 3 to 6% by weight. The antiviral film according to claim 1 or 2, wherein the film body is a food packaging film. A food packaging bag characterized by being composed of the antiviral film described in claim 3.