Film, laminated film, and packaging material

Abstract

This film comprises a recycled material-containing layer containing a recycled material including a polyolefin-based resin, has a haze of 3-25%, and has a thickness of 50-200 μm or less.

Description

Films, laminated films, and packaging materials

[0001] This invention relates to films, laminated films, and packaging materials.

[0002] Generally, plastic films are lightweight, chemically stable, easy to process, flexible, strong, and can be mass-produced, making them suitable for a wide range of applications. Their uses are diverse, including packaging materials for food and pharmaceuticals, intravenous drip bags, shopping bags, posters, tapes, optical films used in LCD televisions, protective films, window films, greenhouses, and building materials. Materials used for plastic films include thermoplastic resins such as polyethylene, polypropylene, polystyrene, acrylic polymethyl methacrylate, polycarbonate, polyamide, polyethylene terephthalate, and polybutylene terephthalate, as well as thermosetting resins such as epoxy resins, polyurethane, and polyimide.

[0003] Plastic films are made by selecting appropriate plastic materials according to their intended use, and sometimes multiple layers are stacked to form laminated films. Furthermore, in plastic films, multiple plastic materials are mixed into a single layer to compensate for the shortcomings of a single material. In addition, plastic films may contain aluminum to provide light-blocking properties, printing inks to enhance the product's design, and adhesives to bond incompatible plastic materials.

[0004] In response to recent environmental issues, the recycling of plastic products is expected to play a significant role, and various recycling methods are being considered. For example, in the field of PET bottles, material recycling, which involves washing and crushing collected products for reuse as raw materials, and chemical recycling, which involves monomerization, have been established technologies.

[0005] Globally, there is a growing trend towards policies that prohibit the use of resin products made solely from petroleum-derived resins, making the use of recycled materials essential. The use of recycled materials is also being considered in the field of film products such as packaging materials. For example, Patent Document 1 below proposes a sealant film containing recycled polyethylene resin.

[0006] International Publication No. 2022 / 124229

[0007] Incidentally, aluminum, which is used to provide barrier properties to packaging materials, can act as a foreign substance and degrade the mechanical properties of recycled materials. Therefore, from the perspective of repeatedly recycling film products, there is a demand for applying sealant films containing recycled materials to packaging materials that do not have an aluminum layer. In addition, packaging materials that do not have an aluminum layer are often used in applications where it is desirable for the contents and product information to be easily visible from the perspective of safety and sales promotion, such as transparent packaging materials used for food and cosmetic packaging pouches and refill pouches for toiletries. In this case, the sealant film that makes up the packaging material is required to have not only good lamination compatibility with other layers but also excellent transparency.

[0008] Patent Document 1 evaluates the deodorizing and opacity properties of sealant films, but it does not examine the impact of recycled materials on heat sealability or their suitability for lamination with other layers.

[0009] Therefore, the first object of the present invention is to provide a film containing recycled material that has lamination suitability and transparency, as well as a laminated film and packaging material equipped therewith. The second object of the present invention is to provide a sealant film containing recycled material that has sufficient heat sealability, lamination suitability and transparency, as well as a laminated film and packaging material equipped therewith.

[0010] Furthermore, when using packaging bags such as pouches as raw materials for recycled materials, there is a possibility that impurities such as ink components may be mixed into the recycled material. In this case, if the recycled material content in the sealant film is increased, the transparency may be impaired due to discoloration caused by the impurities.

[0011] On the other hand, from the standpoint of heat sealability and impact resistance, it is desirable that the recycled material used in sealant films contains polyethylene resin. However, depending on the raw materials of the recycled material, there is a possibility that impurities such as resins other than polyethylene resin may be mixed in. In this case, if the recycled material content in the sealant film is increased, the mechanical properties will be insufficient compared to films made only from virgin resin, making it more prone to problems such as punctures and damage to pouch packaging bags.

[0012] Therefore, a third object of the present invention is to provide a sealant film that contains recycled material while having sufficient transparency and mechanical properties, as well as a laminated film and packaging material using the sealant film.

[0013] One aspect of the present invention relates to the following [1] to

[11] .

[0014] [1] A film comprising a recycled material-containing layer containing a recycled material including a polyolefin resin, wherein the haze is 3% or more and 25% or less, and the thickness is 50 μm or more and 200 μm or less. [2] The film according to [1], wherein the internal haze is 1% or more and 15% or less. [3] The film according to [1] or [2], wherein when the reference light is transmitted from a CIE standard light source D65 with a 2-degree field of view, the color difference ΔE of the transmitted light in the L*a*b* color space with respect to the reference light is 10 or less. [4] The film according to any one of [1] to [3], wherein the content of the polyolefin resin in the recycled material-containing layer is 98% by mass or more, based on the total amount of the recycled material-containing layer. [5] The film according to any one of [1] to [4] used as a sealant film. [6] A laminated film comprising the film according to any one of [1] to [5]. [7] The laminated film according to [6], further comprising a substrate laminated to the film via an adhesive layer, wherein the adhesive layer and the recycled material-containing layer are adjacent to each other, and the film is a sealant layer. [8] A packaging material comprising the film according to any one of [1] to [5]. [9] The packaging material according to [8], further comprising a substrate laminated to the film via an adhesive layer, wherein the adhesive layer and the recycled material-containing layer are adjacent to each other, and the film is a sealant layer.

[10] The packaging material according to [8] or [9], wherein the content of plastic material contained in the recycled material is 10% by mass or more based on the total amount of plastic material in the packaging material.

[11] The packaging material according to any one of [8] to

[10] , which does not have a layer containing aluminum.

[0015] Another aspect of the present invention relates to the following [1] to [5].

[0016] [1] A sealant film comprising a recycled material-containing layer containing recycled material, wherein the recycled material contains a polyethylene resin, the recycled material content is 15% by mass or more based on the total amount of the sealant film, and the sealant film has a density of 0.917 g / cm³ such that when the reference light is transmitted through a CIE standard light source D65 with a two-degree field of view, the color difference ΔE of the transmitted light with respect to the reference light in the L*a*b* color space is 10 or less. ３ 0.934g / cm or more ３ The sealant film is as follows: [2] The sealant film according to [1], having a thickness of 50 μm or more and 200 μm or less. [3] A laminated film comprising the sealant film according to [1] or [2]. [4] A packaging material comprising the sealant film according to [1] or [2]. [5] The packaging material according to [4], which does not have an aluminum-containing layer.

[0017] According to the present invention, it is possible to provide a film that contains recycled materials while having lamination suitability and transparency, as well as a laminated film and packaging material equipped therewith.

[0018] Because the film according to the present invention possesses the above-mentioned properties, it is highly applicable to packaging materials that are suitable for repeated recycling, such as transparent packaging materials that do not have an aluminum layer or the like.

[0019] Furthermore, according to the present invention, it is possible to provide a sealant film that contains recycled material while having sufficient heat sealability, lamination suitability, and transparency, as well as a laminated film and packaging material equipped therewith.

[0020] Because the sealant film according to the present invention possesses the above-mentioned properties, it is highly applicable to packaging materials that are suitable for repeated recycling, such as transparent packaging materials that do not have an aluminum layer or the like.

[0021] Furthermore, according to the present invention, it is possible to provide a second sealant film that contains recycled material while having sufficient transparency and mechanical properties, as well as a laminated film and packaging material using this sealant film.

[0022] Because the second sealant film according to the present invention possesses the above-mentioned properties, it is highly applicable to packaging materials that are suitable for repeated recycling, such as transparent packaging materials that do not have an aluminum layer or the like.

[0023] This is a schematic cross-sectional view showing an example of a sealant film. This is a schematic cross-sectional view showing another example of a sealant film. This is a schematic cross-sectional view showing yet another example of a sealant film. This is a schematic cross-sectional view showing an example of a laminated film. This is a diagram illustrating the difference in visibility inside a sealant film. This is another diagram illustrating the difference in visibility inside a sealant film.

[0024] The present invention will be described in detail below. Figures 1 to 4 are schematic diagrams, and the size and shape of each part have been exaggerated as appropriate for ease of understanding. Furthermore, the embodiments shown below illustrate configurations for realizing the technical idea of ​​the present invention, and the technical idea of ​​the present invention is not limited to the materials, shapes, structures, etc. of the components described below. The technical idea of ​​the present invention can be modified in various ways within the technical scope defined by the claims described in the patent claims.

[0025] <Film> The film of this embodiment comprises a recycled material-containing layer containing a recycled material including a polyolefin resin.

[0026] (First Film) The first film of this embodiment contains recycled material and, from the viewpoint of satisfying lamination suitability and transparency, has a haze of 3% to 25% and a thickness of 50 μm to 200 μm.

[0027] In this specification, film haze refers to the sum of external haze and internal haze. The film haze, internal haze, and external haze may be measured according to JIS K 7105.

[0028] The film of this embodiment can be used as a sealant film, a base film, or the like. When the film of this embodiment is used as a base film, it may be a base film for a pouch. Regarding the film of this embodiment, the case where the first film is used as a sealant film will be described in detail below as an example.

[0029] The haze of the sealant film can be measured from the surface opposite to the layer that functions as the sealant layer. That is, when both surfaces of the sealant film are a recycled material-containing layer or a recycled material-free layer, the measurement can be performed from either surface. When one surface of the sealant film is a recycled material-containing layer and the other surface is a recycled material-free layer, the measurement can also be performed from the surface on the recycled material-free layer side.

[0030] When the sealant film has a haze of 25% or less and a thickness of 200 μm or less, it becomes easier to ensure the visibility of the contents when applied to a transparent packaging material or the like. When the haze is 3% or more and the thickness is 50 μm or more, it becomes easier to ensure heat-sealability and laminability while using recycled materials. The sealant film of this embodiment is provided with a recycled material-containing layer so as to satisfy the above conditions, and thus can have sufficient heat-sealability, laminate suitability, and transparency while using a recycled material containing a polyolefin-based resin. In addition, since the sealant film of this embodiment has a thickness of 50 μm or more, it becomes easy to suppress the occurrence of perforations and the deterioration of heat-sealability even when foreign substances derived from recycled materials are included.

[0031] Incidentally, the haze of the sealant film of the present embodiment can reflect external haze due to surface irregularities and internal haze due to foreign matter pieces derived from recycled materials (for example, a dispersion of components other than polyolefin resins). An increase in external haze means a decrease in the smoothness of the film surface, leading to a decrease in lamination suitability. Also, an increase in internal haze means that a large number of dispersions are present inside the film, leading to a decrease in transparency. When the transparency of the sealant film decreases, there is a risk that the visibility of the contents deteriorates when applied to a transparent packaging material.

[0032] From the viewpoints of lamination suitability and transparency, the haze of the sealant film of the present embodiment may be 3% or more and 15% or less.

[0033] From the viewpoint of lamination suitability, the external haze of the sealant film of the present embodiment may be 2% or more and 15% or less, or may be 7% or more and 10% or less.

[0034] Also, the internal haze of the sealant film of the present embodiment may be 1% or more and 15% or less, or may be 1% or more and 8% or less. In this case, while using recycled materials, it becomes easy to achieve both the surface smoothness required for lamination suitability and the transparency (particularly, the visibility of the contents when applied to a transparent packaging material).

[0035] To reduce internal haze in sealant films, it is effective to refine foreign material fragments derived from recycled materials (e.g., dispersions of components other than polyolefin resins) and reduce their aspect ratio. For example, the following methods can be used, and two or more methods may be combined. Note that the following methods are merely examples, and measures that lead to a reduction in the size and aspect ratio of the dispersions are not limited to those listed below. (a) Reduce the proportion of recycled material in the recycled material-containing layer. (b) Increase the proportion of the resin that has the largest content in the recycled material. (c) When extruding recycled material, increase the screw rotation speed. (d) When extruding the recycled material-containing layer, avoid narrowing the flow path as much as possible and use a configuration that is less susceptible to tensile stress. (e) Use recycled material by repelling it using a twin-screw extruder or by mixing it with virgin resin to form a masterbatch. (f) When molding the recycled material-containing layer, mix in a compatibilizer that improves the affinity between the polyolefin resin and components other than polyolefin resin contained in the recycled material.

[0036] The sealant film of this embodiment uses a CIE standard light source D65 with a two-degree field of view as the reference light source, and when the reference light is transmitted through the film, the color difference ΔE of the transmitted light in the L*a*b* color space relative to the reference light may be 10 or less, or 8 or less. The above-mentioned L*a*b* color space values ​​of the visible light and transmitted light can be obtained, for example, by a blank measurement using a spectrochromatic color haze meter (manufactured by Nippon Denshoku Industries, Ltd., product name "COH7700", light source: D65) without placing the sealant film, and by measuring the transmitted light transmitted through the sealant film.

[0037] In this specification, CIE standard light source D65 refers to a light source representing average daylight with a correlated color temperature of approximately 6500 K, and may be any light source having the same statistically equivalent relative spectrum.

[0038] The L*a*b* color space values ​​may be measured, for example, in the wavelength range of 400 nm to 700 nm at 10 nm intervals of output wavelength.

[0039] Note that in this specification, the color difference is the perceived color separation between two colors defined by JIS 8730, and ΔE is the quantified value thereof. More specifically, ΔE is the distance between two points in the color space in the L*a*b* color system, and is the value calculated by the following formula. ΔE = { (ΔL*) ２ + (Δa*) ２ + (Δb*) ２} １／２

[0040] (Second Film) The film of this embodiment contains a recycled material, and from the perspective of satisfying sufficient transparency and mechanical properties, it has a recycled material-containing layer containing a recycled material containing a polyethylene-based resin. The content of the recycled material is 15% by mass or more based on the total amount of the film. When the standard light source D65 of the CIE two-degree field is used as the reference light and this reference light is transmitted, the color difference ΔE in the L*a*b* color space of the transmitted light with respect to the reference light is 10 or less, and the density is 0.917 g / cm ３ or more and 0.934 g / cm ３ or less may be acceptable.

[0041] In this specification, the density of the film is the true density measured in accordance with JIS Z 8837. The density of the sealant film can be measured, for example, by using a vacuum density measuring device (manufactured by MICROTRAC Co., Ltd., product name "BELPYCN0").

[0042] The second film of this embodiment can also be used as a sealant film, a base film, etc. When the film of this embodiment is used as a base film, it may be a base film for a pouch.

[0043] When the second film is a sealant film (hereinafter, it may also be referred to as the second sealant film), the above color difference ΔE being 10 or less and the density of the sealant film being 0.934 g / cm ３ or less makes it easier to ensure sufficient transparency, heat sealability, and impact resistance. When the density of the sealant film is 0.917 g / cm ３As a result, it becomes easier to ensure blocking resistance and rigidity. The second sealant film, by having a recycled material-containing layer provided to satisfy the above conditions, can contain 15% or more by mass of recycled material containing polyethylene resin based on the total amount of the sealant film, while still possessing sufficient transparency and mechanical properties.

[0044] From the standpoint of transparency, the above-mentioned color difference ΔE of the second sealant film may be 9 or less, or 8 or less.

[0045] The above-mentioned color difference ΔE of the second sealant film may be 3.8 or greater, or 4 or greater.

[0046] From the viewpoint of blocking resistance and rigidity, the density of the second sealant film is 0.918 g / cm³. ３ The above is sufficient, and 0.919 g / cm³ ３ That's fine too.

[0047] From the viewpoint of heat sealability and impact resistance, the density of the second sealant film is 0.933 g / cm³. ３ The following may be true: 0.932 g / cm³ ３ The following is also acceptable.

[0048] From the viewpoint of ensuring visibility of the contents when the second sealant film is applied to transparent packaging materials, the thickness of the sealant film may be 200 μm or less, 180 μm or less, or 160 μm or less. From the viewpoint of making it easier to suppress the occurrence of holes and the decrease in heat sealability even when foreign matter derived from recycled materials is included, the thickness of the sealant film may be 50 μm or more, 60 μm or more, or 70 μm or more.

[0049] The polyethylene resin content in the second sealant film can be calculated using a method that utilizes differential scanning calorimetry (DSC) measurement, as described later.

[0050] Figure 1 is a schematic cross-sectional view showing an example of the first sealant film of this embodiment. The sealant film 1 shown in Figure 1 comprises a recycled material-containing layer 2. The second sealant film can have a similar configuration.

[0051] (Recycled Material-Containing Layer) The recycled material-containing layer contains recycled material containing polyolefin resin (hereinafter sometimes referred to as "PO-containing recycled material"). The PO-containing recycled material may be derived from recycled material made from packaging material consisting of a laminate formed by laminating multiple types of resin sheets containing polyolefin resin and resin sheets that do not contain polyolefin resin, or it may be derived from recycled material made from packaging material consisting of a laminate formed by laminating a resin sheet containing polyolefin resin and resin sheets of the same type, or it may be a mixture of multiple such materials.

[0052] In the case of the second sealant film, the recycled material-containing layer contains recycled material containing polyethylene resin (hereinafter sometimes referred to as "PE-containing recycled material"). The PE-containing recycled material may be derived from recycled material made from packaging material consisting of a laminate formed by laminating multiple types of resin sheets containing polyethylene resin and resin sheets that do not contain polyethylene resin, or it may be derived from recycled material made from packaging material consisting of a laminate formed by laminating a resin sheet containing polyethylene resin and resin sheets of the same type, or it may be a mixture of multiple such materials.

[0053] The recycled material-containing layer may contain multiple types of PO-containing recycled materials. In the case of the second sealant film, the recycled material-containing layer may contain multiple types of PE-containing recycled materials.

[0054] PO-containing recycled materials such as PE-containing recycled materials may be those that have undergone the separation treatment described later.

[0055] As raw materials for recycled materials, for example, post-consumer recycling (PCR) can be used, which includes bottles and packaging bags for beverages, detergents, and condiments that have been collected from the market, food containers for bento boxes and instant noodles, packaging bags for food and garbage bags, and plastic products such as hangers, stationery, daily necessities, home appliances, and toys. Post-industry recycling (PIR) can be used, which includes defective products that do not become finished products discharged from factories, scraps generated during the manufacturing process, and plastic products used for transportation and packaging.

[0056] In the sealant film of this embodiment, from the viewpoint of material recycling of plastic film, a laminated film (packaging material) made by laminating multiple types of resin sheets, a packaging bag made by forming a bag therefrom, a laminated film (packaging material) made by laminating the same type of resin sheets, or a packaging bag made by forming a bag therefrom, or a mixture thereof may be used. Examples of packaging bags include refill pouches for toiletries.

[0057] The recycled material contained in the recycled material-containing layer may be washed and crushed as needed. Compared to resins obtained through chemical recycling, such as thermal decomposition, recycled material has the advantage of requiring less energy during recycling. Therefore, increasing the proportion of recycled material in the recycled material-containing layer reduces the environmental burden.

[0058] Examples of polyolefin resins included in recycled materials include polyethylene resins such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), and ethylene-α-olefin copolymers, as well as polypropylene resins such as homopolypropylene (PP), block polypropylene, random polypropylene, and propylene-α-olefin copolymers.

[0059] The polyolefin resin content in PO-containing recycled material may be 70% by mass or more, 80% by mass or more, 90% by mass or more, 94% by mass or more, 95% by mass or more, 97% by mass or more, 98% by mass or more, 98.5% by mass or more, 99% by mass or more, 99.9% by mass or more, or 100% by mass, or 99.9% by mass or less, based on the total amount of PO-containing recycled material.

[0060] In the case of the second sealant film, the polyethylene resin content in the PE-containing recycled material may be 70% by mass or more, 80% by mass or more, 90% by mass or more, 94% by mass or more, 95% by mass or more, 97% by mass or more, 98% by mass or more, 98.5% by mass or more, 99% by mass or more, 99.9% by mass or more, or 100% by mass, or 99.9% by mass or less, based on the total amount of the PE-containing recycled material.

[0061] Furthermore, in cases where the composition of recycled material is known, such as in post-industry recycling (PIR), the content ratio of polyolefin resin in the thermoplastic resin component contained in the recycled material can be used to select PO-containing recycled material or to adjust the content of PO-containing recycled material in the recycled material-containing layer, using the differential scanning calorimeter (DSC) measurement method described below. [Calculation of the content ratio of polyolefin resin (PO resin) by DSC measurement] Using a differential scanning calorimeter, the heat of fusion of each individual PO resin and other thermoplastic resins that constitute the recycled material, and the heat of fusion of PO resin and other thermoplastic resins in the recycled material are measured, and the content ratio of PO resin is calculated from these values.

[0062] In the case of the second type of sealant film, the heat of fusion of each individual PE resin and other thermoplastic resins that constitute the recycled material, as well as the heat of fusion of the PE resin and other thermoplastic resins in the sealant film, can be measured, and the content of the PE resin can be calculated from these values. Furthermore, if the sealant film contains virgin PE resin, the heat of fusion of each individual PE resin and other thermoplastic resins that constitute the recycled material, as well as the heat of fusion of the PE resin and other thermoplastic resins in the sealant film, and the heat of fusion of the virgin PE resin alone can be measured, and the content of the PE resin can be calculated from these values.

[0063] DSC measurements are performed under the conditions of a temperature range of 0°C to 300°C and a heating rate of 10°C / min, and the heat of fusion between 50°C and 140°C can be used as the heat of fusion for PO resins. For other thermoplastic resins, the heat of fusion can be determined based on the melting point of the resin. For example, if the recycled material contains PO resin, nylon (Ny) resin, and polyethylene terephthalate (PET) resin as thermoplastic resins, the content ratio of PO resin in the recycled material can be calculated from the following formula 1. The percentage of PO resin content in recycled material (%) = (x / X) × 100 / [(x / X) + (y / Y) + (z / Z)] .... (Equation 1) [In Equation 1, x, y, and z represent the heat of fusion [mJ / mg] of PO resin, Ny resin, and PET resin obtained by DSC measurement of the recycled material, respectively, and X, Y, and Z represent the heat of fusion [mJ / mg] of virgin PO resin, virgin Ny resin, and virgin PET resin constituting the recycled material, respectively.]

[0064] In the case of the second sealant film, the heat of fusion at 50°C to 140°C can be used as the heat of fusion for the PE resin (PE).

[0065] The PO-containing recycled material may have a polyolefin resin content of 90% by mass or more, 94% by mass or more, 95% by mass or more, 97% by mass or more, 98% by mass or more, 98.5% by mass or more, 99% by mass or more, 99.9% by mass or more, or 100% by mass, as calculated based on the above DSC measurement. In this case, it becomes easier to ensure the transparency, heat sealability, and lamination suitability of the sealant film.

[0066] The recycled material-containing layer may consist solely of recycled material, or it may contain virgin material. Preferably, the virgin material is the same type of virgin resin as the polyolefin resin in the PO-containing recycled material.

[0067] If the recycled material-containing layer contains virgin material, the virgin material content may be 10 to 900 parts by mass, 40 to 600 parts by mass, or 70 to 300 parts by mass per 100 parts by mass of recycled material, and from the viewpoint of recyclability, it may be 10 to 100 parts by mass.

[0068] The content of polyolefin resin derived from PO-containing recycled material in the recycled material-containing layer may be 10% by mass or more, 15% by mass or more, 20% by mass or more, 25% by mass or more, 40% by mass or more, 45% by mass or more, 50% by mass or more, 60% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, or 100% by mass, based on the total amount of the recycled material-containing layer.

[0069] The content of polyolefin resin in the recycled material-containing layer may be 97% by mass or more, 98% by mass or more, 98.5% by mass or more, 99% by mass or more, 99.9% by mass or more, or 100% by mass, or 99.9% by mass or less, based on the total amount of the recycled material-containing layer.

[0070] Furthermore, the content of polyolefin resin in the recycled material-containing layer, based on the above DSC measurement, may be 97% by mass or more, 98% by mass or more, 98.5% by mass or more, 99% by mass or more, 99.9% by mass or more, or 100% by mass, and may be 99.9% by mass or less.

[0071] The thickness of the recycled material-containing layer may be 50 μm to 200 μm, or 100 μm to 150 μm. In this case, it becomes easier to ensure the heat-sealability and transparency of the sealant film.

[0072] The recycled material-containing layer may be a single layer, or it may be a multilayer consisting of multiple layers with different types and / or amounts of recycled material. If the recycled material-containing layer is a multilayer, the amount of polyolefin resin in each layer may satisfy the conditions described above.

[0073] The recycled material-containing layer may contain various additives as needed. Examples of additives include compatibilizers, nucleating agents, reinforcing fillers, antioxidants, heat stabilizers, weathering agents, light stabilizers, plasticizers, UV absorbers, antistatic agents, flame retardants, flame retardant enhancers, slip agents, antiblocking agents, antifogging agents, lubricants, pigments, dyes, dispersants, copper damage inhibitors, neutralizing agents, anti-bubble agents, weld strength improvers, natural oils, synthetic oils, waxes, etc. These may be used individually or in combination of two or more.

[0074] The compatibilizer may be a reactive or non-reactive compatibilizer. Examples of compatibilizers include acid-modified polyolefin resins, ethylene-vinyl acetate copolymers, ethylene-methyl methacrylate copolymers, and ethylene-vinyl alcohol copolymers.

[0075] Examples of nucleating agents and reinforcing fillers include metals such as talc, silica, clay, montmorillonite, calcium carbonate, lithium alumina carbonate, titanium dioxide, aluminum, iron, silver, and copper; hydroxides such as aluminum hydroxide and magnesium hydroxide; celluloses such as cellulose microfibrils and cellulose acetate; fibrous fillers such as glass fibers, polyethylene terephthalate fibers, nylon fibers, polyethylene naphthalate fibers, aramid fibers, vinylon fibers, and polyacrylate fibers; carbons such as carbon nanotubes; and elastomers such as ethylene propylene rubber (EPR).

[0076] Examples of antioxidants include phenolic compounds, organic phosphite compounds, and thioether compounds. The antioxidant content should be between 500 ppm and 3000 ppm relative to the resin to suppress the deterioration of film quality. If the antioxidant content is less than 500 ppm, the antioxidant effect becomes difficult to obtain, while if the antioxidant content exceeds 3000 ppm, bleed-out and deterioration of appearance due to antioxidant decomposition products are more likely to occur.

[0077] Examples of heat stabilizers include hindered amine compounds.

[0078] Examples of UV absorbers include benzophenone compounds, benzotriazole compounds, and benzoate compounds.

[0079] Examples of antistatic agents include nonionic compounds, cationic compounds, and anionic compounds.

[0080] Examples of flame retardants include halogen compounds, phosphorus compounds, nitrogen compounds, inorganic compounds, boron compounds, silicone compounds, sulfur compounds, and red phosphorus compounds.

[0081] Examples of flame retardant additives include antimony compounds, zinc compounds, bismuth compounds, magnesium hydroxide, and clayey silicates.

[0082] Figure 2 is a schematic cross-sectional view showing another example of the first sealant film of this embodiment. The sealant film 1a shown in Figure 2 comprises a recycled material-containing layer 2 and a recycled material-free layer 3a laminated on one main surface of the recycled material-containing layer 2. The second sealant film may have a similar configuration.

[0083] Figure 3 is a schematic cross-sectional view showing yet another example of the first sealant film of this embodiment. The sealant film 1b shown in Figure 3 comprises a recycled material-containing layer 2 and recycled material-free layers 3a and 3b laminated on the main surfaces of both recycled material-containing layers 2. The second sealant film may have a similar configuration.

[0084] The recycled material-free layers 3a and 3b can be made from virgin material. The virgin material can be appropriately selected from general thermoplastic resins used as sealant layers or laminate layers, but it may be the same type of virgin resin as the resin that makes up the largest proportion of the recycled material. In this case, high adhesion is more easily obtained. When a recycled material-free layer is provided on only one side, as in the sealant film 1a, using the recycled material-free layer as a sealant layer is advantageous in that high heat sealability can be obtained.

[0085] Examples of virgin resins include polyethylene, polypropylene, polystyrene, polymethyl methacrylate, ethylene vinyl acetate, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyvinylidene chloride, polyacrylonitrile, polylactic acid, cyclic polyolefin, polycarbonate, polyamide, polyethylene terephthalate, polybutylene terephthalate, and derivatives thereof. These may be used individually or in combination of two or more.

[0086] The virgin resin contained in the recycled material-free layers 3a and 3b may be the same type of resin or a different type of resin.

[0087] The recycled material-free layers 3a and 3b may contain the additives described above as needed. The additives may be used individually or in combination of two or more types.

[0088] The thickness of the recycled material-free layers 3a and 3b may be between 12 μm and 67 μm.

[0089] <Method for Manufacturing a Sealant Film> The first sealant film of this embodiment can be manufactured by a method comprising, for example, step A, preparing a recycled material containing a polyolefin resin (PO-containing recycled material), and step B, forming a recycled material-containing layer-forming composition containing the PO-containing recycled material to obtain a sealant film having a recycled material-containing layer. The second sealant film can also be manufactured in the same manner as described above, except that in step A, a recycled material containing a polyethylene resin (PE-containing recycled material) is prepared.

[0090] (Process A) In Process A, recycled material containing polyolefin resin (PO-containing recycled material) is prepared.

[0091] PO-containing recycled material can be obtained from the raw materials of the various recycled materials mentioned above. It can be obtained by recovering, washing, and crushing the raw materials of the recycled material, or by melt-molding a mixture with other components in an extruder and forming it into pellets.

[0092] PO-containing recycled material may be subjected to separation treatment to remove components other than polyolefin resin or to isolate polyolefin resin, and may be subjected to at least one of the following treatments. Recycled material subjected to these separation treatments may be highly transparent. (a) Chemical treatment (b) Filter treatment

[0093] In chemical treatment, the raw materials of the recycled material after washing (e.g., pulverized material) can be treated with chemicals to remove resins other than polyolefin resins, adhesives, ink components, etc. This reduces the amount of dispersion of components other than polyolefin resins in the formed recycled material-containing layer, which can cause deterioration of the surface condition and a decrease in transparency.

[0094] Chemical treatment allows for the removal of the printed layer by stripping and deinking ink components. This reduces the amount of foreign matter that causes a decrease in transparency in the recycled material-containing layer formed from recycled raw materials.

[0095] One example of chemical treatment is alkaline solution treatment, which involves immersing the raw materials of recycled materials in an alkaline solution.

[0096] Basic compounds found in alkaline solutions include, for example, sodium hydroxide (NaOH), potassium hydroxide (KOH), and calcium hydroxide (Ca(OH)). ２ ), barium hydroxide (Ba(OH) ２ ), sodium carbonate (Na ２ CO ３ Examples include tetramethylammonium hydroxide, etc. The content of basic compounds in the alkaline solution may be 0.5% by mass or more, 1% by mass or more, or 2% by mass or more, and may be 20% by mass or less, 15% by mass or less, or 10% by mass or less, based on the total amount of the alkaline solution.

[0097] The alkaline solution may contain a surfactant. The surfactant primarily plays a role in improving the desorption properties of the printing layer and adhesive. This is because the surfactant makes it easier for the alkaline solution to penetrate the printing layer and adhesive, thereby promoting their desorption. In addition, the surfactant adsorbs onto the surface of the desorbed components (various desorbed layers) and the deinking substrate, which can suppress the re-adhesion of the desorbed components to the deinking substrate.

[0098] The temperature of the alkaline solution may be 30°C or higher, 40°C or higher, or 50°C or higher, and may be 100°C or lower, 90°C or lower, or 80°C or lower.

[0099] The raw materials for the recycled material may be 2% by mass or more, 3% by mass or more, or 5% by mass or more, and may be 50% by mass or less, 40% by mass or less, or 30% by mass or less, relative to the total amount of the alkaline solution.

[0100] The contact time (immersion time or stirring time) between the recycled material raw material and the alkaline aqueous solution may be 3 minutes or more, 10 minutes or more, or 15 minutes or more, and may be 5 hours or less, 4 hours or less, or 3 hours or less.

[0101] When stirring an alkaline solution, the stirring speed may be 20 rpm or more, 50 rpm or more, or 100 rpm or more, and may be 5000 rpm or less, 4000 rpm or less, or 3000 rpm or less.

[0102] In the filtering process, the fluid obtained by molten recycled material raw materials can be filtered using a predetermined filter. This reduces the amount of foreign matter from the recycled material raw materials that can cause deterioration of the surface condition and reduction of transparency in the recycled material-containing layer that is formed.

[0103] The pore size of the filter used in the filtering process may be 4 μm or larger, 20 μm or larger, or 80 μm or larger, and may be 450 μm or smaller, 260 μm or smaller, or 180 μm.

[0104] In the filtering process, the filtration rate of the fluid containing the molten raw materials of the recycled material may be 180 mL / min or more, 360 mL / min or more, 540 mL / min or more, or 900 mL / min or more, and may be 3600 mL / min or less, 2700 mL / min or less, 1800 mL / min or less, or 1400 mL / min or less.

[0105] In the filtering process, the melting temperature of the recycled material may be 170°C or higher, 200°C or higher, or 230°C or higher, and may be 300°C or lower, 280°C or lower, or 250°C or lower.

[0106] The filter can be made by stacking multiple metal meshes of different mesh sizes. The mesh sizes of the metal meshes may be 2 to 795 mesh, 20 to 795 mesh, 40 to 635 mesh, or 40 to 100 mesh.

[0107] Furthermore, when using PO-containing recycled material that has undergone the separation treatment described above, unpelletized PO-containing recycled material (for example, crushed waste material) may be directly fed into the film-forming machine. By omitting the step of pelletizing the PO-containing recycled material or a mixture of PO-containing recycled material and other components, thermal degradation of the material can be suppressed.

[0108] (Step B) In Step B, a conventionally known film-forming method can be employed. For example, the composition for forming the recycled material-containing layer can be melted in an injection molding machine or an extrusion molding machine (e.g., a twin-screw extruder), and then a film can be formed using a T-die via a feed block or multi-manifold, or by an inflation method. If the sealant film has a multilayer structure, for example, a method of extruding and laminating the recycled material-containing layer using an extrusion laminating machine, or a method of forming the recycled material-containing layer and other layers (e.g., non-recycled material layers) by co-extrusion molding using a multilayer extrusion molding machine can be used.

[0109] The composition for forming a recycled material layer may contain only recycled material, or it may further contain virgin material or the aforementioned additives to impart various desired properties such as viscosity adjustment and mechanical property reinforcement. Furthermore, when mixing recycled material and virgin material, it may be a dry blend in which the virgin material and recycled material are simultaneously put into a hopper and melt-kneaded to form a film, or it may be a melt blend in which the virgin material and recycled material are melt-kneaded separately in a twin-screw extruder to form a masterbatch. From the viewpoint of transparency, the latter is preferred.

[0110] From the viewpoint of reducing aggregates in the recycled material-containing layer, repelletizing using a twin-screw extruder, molding under high shear conditions, or incorporating acid-modified polyolefin resin as a compatibilizer may be used.

[0111] Regarding the cooling method for the film, it is possible to use methods similar to those used for the molding machine described above. For example, in the T-die method, air cooling methods such as air chambers, vacuum chambers, and air knives, or water cooling methods such as dipping the cooling roll into a chilled water pan can be used. Furthermore, when imparting surface irregularities through shaping, a method may be used in which molten resin is introduced into a contact area between a nip roll made of silicone rubber, NBR rubber, or fluororesin and a cooling roll made of machined metal, under a pressure of 0.1 MPa or higher, and then cooled.

[0112] In the manufacturing method of this embodiment, the sealant film may be subjected to a surface modification treatment for the purpose of improving post-process suitability such as printability and lamination suitability. As surface modification treatments, methods that cause functional groups to appear by oxidizing the film surface, such as corona discharge treatment, plasma treatment, and flame treatment, or wet process modification treatments such as coating of an easy-adhesion layer can be used.

[0113] Furthermore, in the manufacturing method of this embodiment, the sealant film formed by the molding machine can be subjected to in-line or off-line stretching, and other necessary processes can be performed as appropriate.

[0114] <Laminated Film> The laminated film of this embodiment comprises the film of this embodiment. In the laminated film of this embodiment, the film of this embodiment may comprise a first sealant film or a second sealant film. In this case, a functional layer may be provided on one side of the sealant film. If the sealant film has a multilayer structure, the functional layer can be provided on the side of the sealant film opposite to the side that functions as a sealant layer. Furthermore, in the laminated film of this embodiment, the recycled material-containing layer in the first sealant film or the second sealant film may be adjacent to other layers (for example, a functional layer).

[0115] For example, when a laminated film is used as a food packaging material, a film with gas barrier properties is required, so the functional layer may be a gas barrier layer with gas barrier properties.

[0116] Furthermore, the laminated film of this embodiment may have a structure in which the recycled material-containing layer in the film of this embodiment is laminated to other layers via an adhesive layer, or the recycled material-containing layer in the first sealant film or the second sealant film may have a structure in which the recycled material-containing layer is laminated to other layers (e.g., a substrate) via an adhesive layer. From the viewpoint of ease of recycling, the substrate preferably contains a polyolefin resin.

[0117] Figure 4 is a schematic cross-sectional view showing an example of a laminated film of this embodiment. The laminated film 9 shown in Figure 4 comprises a sealant film 1b having a recycled material-containing layer 2 and recycled material-free layers 3a and 3b laminated on both main surfaces of the recycled material-containing layer 2; a first base film 6 provided on the recycled material-free layer 3b of the sealant film 1b via an adhesive layer 5a; and a second base film 8 having a printing layer 7 provided on the side of the first base film 6 opposite to the sealant film 1b via an adhesive layer 5b.

[0118] The adhesives constituting the adhesive layers 5a and 5b are not particularly limited, but dry laminating adhesives can be used. Examples of dry laminating adhesives include two-component curing urethane adhesives, polyester urethane adhesives, polyether urethane adhesives, acrylic adhesives, polyester adhesives, polyamide adhesives, epoxy adhesives, and the like.

[0119] The first base film 6 and the second base film 8 are not particularly limited as long as they have mechanical strength and dimensional stability, but plastic films, paper, nonwoven fabrics, etc., can be used. Examples of constituent materials for the plastic film include polyethylene terephthalate (PET), polyester such as polyethylene naphthalate, polyolefins such as polyethylene and polypropylene, polystyrene, polyamides such as nylon 6, polycarbonate, polyacrylonitrile, and polyimide. From the viewpoint of easy recycling, polyolefins such as polyethylene and polypropylene are preferred.

[0120] As an example of the combination of the first base film 6 and the second base film 8, the first base film may be a nylon film and the second base film may be a polyethylene terephthalate film.

[0121] The printed layer 7 may represent characters, patterns, symbols, or combinations thereof.

[0122] From the perspective of producing packaging materials with less environmental impact, the printed layer 7 may be formed using biomass-derived ink.

[0123] The method for forming the printed layer 7 is not particularly limited, and conventionally known printing methods such as gravure printing, offset printing, and flexographic printing can be used. Among these, flexographic printing may be used from the viewpoint of environmental impact.

[0124] The laminated film of this embodiment may have one of the following laminated structures: (1) Substrate / adhesive layer / sealant layer (2) Substrate / adhesive layer / barrier layer (e.g., gas barrier layer) / barrier substrate / adhesive layer / sealant layer (3) Substrate / adhesive layer / barrier substrate / barrier layer (e.g., gas barrier layer) / adhesive layer / sealant layer In each of the above laminated structures, at least one of the substrate, barrier substrate, and sealant layer may be the film of this embodiment.

[0125] For example, the laminated film of this embodiment comprises the film of this embodiment and a substrate laminated on one main surface of the film via an adhesive layer, wherein the film may be a sealant layer.

[0126] The laminated film shown in Figure 4 and the laminated film having the above structure can be used as packaging material.

[0127] From the viewpoint of material recycling, the packaging material (or laminated film) of this embodiment may contain 10% by mass or more, 13% by mass or more, or 25% by mass or more of the recycled plastic material, based on the total mass of plastic material in the packaging material (or laminated film of this embodiment). Furthermore, the packaging material (or laminated film of this embodiment) may contain 10% by mass or more, 13% by mass or more, or 25% by mass or more of the recycled material, based on the total amount of plastic material in the packaging material (or laminated film of this embodiment), in terms of the mass of the recycled material. If the packaging material of this embodiment is a laminated packaging material, materials other than plastic (for example, adhesives, printing inks, aluminum foil, etc.) may be excluded from the mass calculation.

[0128] From the viewpoint of material recycling, the packaging material (or laminated film) of this embodiment may contain recycled material in an amount of 10% by mass or more, 20% by mass or more, 25% by mass or more, 30% by mass or more, 50% by mass or more, or 80% by mass or more, based on the total mass of the packaging material (or laminated film of this embodiment).

[0129] The packaging material of this embodiment can be used for standing pouches, three-sided pouches, gusseted pouches, spout pouches, resealable pouches, ribbed pouches, pillow packaging, and the like.

[0130] <Packaging Bags> The packaging bags of this embodiment are made from the packaging materials of this embodiment described above. The method of making the packaging bags is not particularly limited, but the packaging bags may be standing pouches, three-sided pouches, gusseted pouches, spout pouches, zipper pouches, peak pouches, pillow packaging, etc.

[0131] Although embodiments of the present invention have been illustrated above, it goes without saying that the present invention is not limited to the above embodiments. Furthermore, it is optional to use a combination of the above embodiments.

[0132] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

[0133] <Preparation of Recycled Material> (Recycled Material A1) A film (hereinafter also referred to as "raw material film") was prepared by cutting a film in which the following layers were laminated in this order: LLDPE film (manufactured by Mitsui Chemicals Tohcello Co., Ltd., product name "TUX FC-S", film thickness 100 μm), adhesive layer (layer thickness 3 μm), PET film (manufactured by Toray Film Processing Co., Ltd., product name "VM-PET 1310", film thickness 12 μm), adhesive layer (layer thickness 3 μm), printing layer, and Ny film (manufactured by Toyobo Co., Ltd., product name "Harden Film N1100", film thickness 15 μm). After cutting the film, it was treated with an alkaline solution to extract the LLDPE film. The alkaline solution treatment was carried out under the following conditions: the amount of cut raw material film in the alkaline solution was 5% by mass, the temperature of the alkaline solution was 70°C, the stirring speed of the alkaline solution was 600 rpm, and the treatment time was 3 hours (hereinafter sometimes referred to as "alkaline solution treatment 1"). The extracted LLDPE film was melted and mixed, and the resulting strands were cut and molded into granules to obtain recycled material A1. The adhesive layer described above was formed by dry lamination using an adhesive with LX-500 (manufactured by DIC Graphics Co., Ltd., product name) as the main component, KW75 (manufactured by DIC Graphics Co., Ltd., product name) as the hardener, and NC401 (manufactured by Toyo Ink Co., Ltd., product name) as the solvent.

[0134] (Recycled material A2) After cutting the raw material film, it was treated with an alkaline solution to extract the LLDPE film. The alkaline solution treatment was carried out under the following conditions: the amount of cut raw material film in the alkaline solution was 5% by mass, the temperature of the alkaline solution was 80°C, the stirring speed of the alkaline solution was 600 rpm, and the treatment time was 3 hours (hereinafter, this may also be referred to as "alkaline solution treatment 2"). The extracted LLDPE film was melted and mixed, and the resulting strands were cut and formed into granules to obtain recycled material A2.

[0135] (Recycled material A3) After cutting the raw material film, it was treated with an alkaline solution to extract the LLDPE film. The alkaline solution treatment was carried out under the following conditions: the amount of cut raw material film in the alkaline solution was 5% by mass, the temperature of the alkaline solution was 70°C, the stirring speed of the alkaline solution was 600 rpm, and the treatment time was 2 hours (hereinafter, this may also be referred to as "alkaline solution treatment 3"). The extracted LLDPE film was melted and mixed, and the resulting strands were cut and formed into granules to obtain recycled material A3.

[0136] (Recycled material A4) After cutting the raw material film, it was treated with an alkaline solution to extract the LLDPE film. The alkaline solution treatment was carried out under the following conditions: the amount of cut raw material film in the alkaline solution was 10% by mass, the temperature of the alkaline solution was 70°C, the stirring speed of the alkaline solution was 600 rpm, and the treatment time was 2 hours (hereinafter, this may also be referred to as "alkaline solution treatment 4"). The extracted LLDPE film was melted and mixed, and the resulting strands were cut and formed into granules to obtain recycled material A4.

[0137] (Recycled material A5) A film consisting of PP film (manufactured by Toray Film Processing Co., Ltd., product name "NO ZK207", film thickness 100 μm), adhesive layer (layer thickness 3 μm), PET film (manufactured by Toray Film Processing Co., Ltd., product name "VM-PET 1310", film thickness 12 μm), adhesive layer (layer thickness 3 μm), printing layer, and Ny film (manufactured by Toyobo Co., Ltd., product name "Harden Film N1100", film thickness 15 μm) laminated in this order was cut, treated with an alkaline solution, and the PP film was extracted. The alkaline solution treatment was carried out under the following conditions: the amount of cut raw film pieces relative to the alkaline solution was 4% by mass, the temperature of the alkaline solution was 80°C, the stirring speed of the alkaline solution was 600 rpm, and the treatment time was 3 hours (hereinafter, this may also be referred to as "alkaline solution treatment 5"). The extracted PP film was melted and mixed, and the resulting strands were cut and molded into granules to obtain recycled material A5.

[0138] (Recycled material A6) After cutting the raw film, the cut film pieces were melted and mixed to obtain strands. At this time, a metal mesh of 40 mesh / 80 mesh / 40 mesh was installed in this order as a filter at the discharge port, and components other than LLDPE were removed by passing the melted and mixed film pieces through the filter (hereinafter sometimes referred to as "filter treatment 1"). The formed strands were cut and molded into granules to obtain recycled material A6.

[0139] (Recycled material A7) After cutting the raw film, the cut film pieces were melted and mixed to obtain strands. At this time, a metal mesh of 40 mesh / 635 mesh / 40 mesh was installed in this order as a filter at the discharge port, and components other than LLDPE were removed by passing the melted and mixed film pieces through the filter (hereinafter sometimes referred to as "filter treatment 2"). The formed strands were cut and molded into granules to obtain recycled material A7.

[0140] (Recycled material A8) After cutting the raw material film, it was melted and mixed, and the resulting strands were cut and formed into granules to obtain recycled material A8.

[0141] (Recycled material A9) After cutting the raw film, the cut film pieces were melted and mixed to obtain strands. At this time, a 30-mesh metal mesh was installed as a filter at the discharge port, and the melted and mixed film pieces were passed through the filter. (Hereinafter, this may also be referred to as "filtering process 3"). The formed strands were cut and molded into granules to obtain recycled material A9.

[0142] (Recycled material A10) After cutting the raw material film, it was treated with an alkaline solution to obtain LLDPE film. The alkaline solution treatment was carried out under the following conditions: the amount of cut raw material film pieces relative to the alkaline solution was 55% by mass, the temperature of the alkaline solution was 70°C, the stirring speed of the alkaline solution was 600 rpm, and the treatment time was 3 hours (hereinafter, this may also be referred to as "alkaline solution treatment 6"). The extracted LLDPE film was melted and mixed, and the resulting strands were cut and formed into granules to obtain recycled material A10.

[0143] (Recycled material A11) After cutting the raw material film, it was treated with an alkaline solution to extract the LLDPE film. The alkaline solution treatment was carried out under the following conditions: the amount of cut raw material film pieces relative to the alkaline solution was 55% by mass, the temperature of the alkaline solution was 70°C, the stirring speed of the alkaline solution was 600 rpm, and the treatment time was 1 minute (hereinafter, this may also be referred to as "alkaline solution treatment 7"). The extracted LLDPE film was melted and mixed, and the resulting strands were cut and formed into granules to obtain recycled material A11.

[0144] [Calculation of Polyolefin Resin (PO Resin) Content by DSC Measurement] Using a differential scanning calorimeter, the heat of fusion of PO resin and other thermoplastic resins, which are raw materials constituting the recycled material, and the heat of fusion of PO resin and other thermoplastic resins in the recycled material were measured, and the content of PO resin was calculated from these values.

[0145] DSC measurements were performed under the following conditions: temperature range: 0°C to 300°C, heating rate: 10°C / min. The heat of fusion between 50°C and 140°C was defined as the heat of fusion for PO resin, between 200°C and 230°C as the heat of fusion for nylon (Ny) resin, and between 230°C and 280°C as the heat of fusion for polyethylene terephthalate (PET) resin.

[0146] The percentage of PO resin in the recycled material was calculated using the following formula 1: Percentage of PO resin in the recycled material (%) = (x / X) × 100 / [(x / X) + (y / Y) + (z / Z)] .... (Formula 1) [In Formula 1, x, y, and z represent the heat of fusion [mJ / mg] of PO resin, Ny resin, and PET resin obtained by DSC measurement of the recycled material, respectively, and X, Y, and Z represent the heat of fusion [mJ / mg] of virgin PO resin, virgin Ny resin, and virgin PET resin constituting the recycled material, respectively.]

[0147] The content ratios of the PO-based resin obtained above are shown in Tables 1 and 2.

[0148]

[0149]

[0150] <Film Preparation> (Example A1) A masterbatch material, which was a melt-blended mixture of recycled material A1 and LLDPE1 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2020") in a weight ratio of 1:1, was put into a hopper for extruding the recycled material-containing layer, and a single-layer film with a thickness of 50 μm was prepared using a single-screw multi-layer extruder.

[0151] (Example A2) Recycled material A2 was placed in a hopper for extruding the recycled material layer, and a single-layer film with a thickness of 50 μm was produced using a single-screw multi-layer extruder.

[0152] (Example A3) A masterbatch material, which was a melt blend of recycled material A3 and LLDPE1 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2020") in a weight ratio of 1:1, was put into a hopper for extruding the recycled material-containing layer, and a single-layer film with a thickness of 50 μm was produced using a single-screw multi-layer extruder.

[0153] (Example A4) A masterbatch material, which was a melt-blended mixture of recycled material A1 and LLDPE1 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2020") in a weight ratio of 1:1, was placed into a hopper for extruding the recycled material-containing layer. Furthermore, Dynacarna D14B (manufactured by Mitsubishi Chemical Corporation, product name) was added to the masterbatch material as a compatibilizer, such that the compatibilizer content was 3% by mass relative to the total mass of the masterbatch material and compatibilizer, and a single-layer film with a thickness of 100 μm was produced using a single-screw multilayer extruder.

[0154] (Example A5) A masterbatch material, which was a melt blend of recycled material A3 and LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP3530") in a weight ratio of 1:1, was put into a hopper for extruding the recycled material-containing layer, and a single-layer film with a thickness of 200 μm was produced using a single-screw multi-layer extruder.

[0155] (Example A6) A masterbatch material, which was a melt blend of recycled material A4 and LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP3530") in a weight ratio of 1:1, was put into a hopper for extruding the recycled material-containing layer, and a single-layer film with a thickness of 50 μm was produced using a single-screw multi-layer extruder.

[0156] (Example A7) Recycled material A5 was placed in a hopper for extruding the recycled material-containing layer, and a single-layer film with a thickness of 50 μm was produced using a single-screw multi-layer extruder.

[0157] (Example A8) A masterbatch material, which is a melt-blended mixture of recycled material A3 and LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP3530") in a weight ratio of 1:1, was put into a core layer hopper for extruding the recycled material-containing layer. LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP3530") was then put into two surface layer hoppers. Using a single-screw multilayer extruder, a layer made of LLDPE2, a recycled material-containing layer, and a layer made of LLDPE2 were laminated in this order, and a three-layer film with a thickness of 150 μm was produced with a layer thickness ratio of 1:1:1.

[0158] (Example A9) A masterbatch material, which was a melt blend of recycled material A6 and LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP3530") in a weight ratio of 1:1, was put into a hopper for extruding the recycled material-containing layer. Then, using a single-screw multilayer extruder, a three-layer film with a thickness of 150 μm was produced, in which LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP3530"), the recycled material-containing layer, and LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP3530") were laminated in the order of LLDPE2, with a layer thickness ratio of 1:1:1.

[0159] (Example A10) Recycled material A7 was put into a hopper for extruding the recycled material-containing layer, and a single-layer film with a thickness of 50 μm was produced using a single-screw multi-layer extruder.

[0160] (Reference Example A1) A commercially available (unused) LLDPE film (manufactured by Tamapoly Co., Ltd., product name "SE620A") was used as the film (thickness 50 μm).

[0161] (Comparative Example A1) A film was prepared in the same manner as in Example A1, except that the film thickness was adjusted to 45 μm.

[0162] (Comparative Example A2) A film was prepared in the same manner as in Example 1, except that a masterbatch material was obtained by dry blending recycled material A1 and LLDPE1 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2020") in a weight ratio of 1:1.

[0163] (Comparative Example A3) A film was prepared in the same manner as in Example A5, except that the film thickness was adjusted to 250 μm.

[0164] (Comparative Example A4) A film was prepared in the same manner as in Example A8, except that a masterbatch material was obtained by dry blending recycled material A1 and LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP3530") in a weight ratio of 1:1.

[0165] (Comparative Example A5) Recycled material A3 and LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP3530") were dry-blended in a weight ratio of 1:1 and added to a core layer hopper for extruding the recycled material-containing layer. LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP3530") was then put into two surface layer hoppers. Using a single-screw multilayer extruder, a layer made of LLDPE2, a recycled material-containing layer, and a layer made of LLDPE2 were laminated in this order, and a three-layer film with a thickness of 150 μm was produced with a layer thickness ratio of 1:1:1.

[0166] (Comparative Example A6) A masterbatch material was prepared by melt-blending recycled material A8 and LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP3530") in a weight ratio of 1:1 in a core layer hopper for extruding the recycled material-containing layer. Dynacarna D14B (manufactured by Mitsubishi Chemical Corporation, product name) was added as a compatibilizer so that the compatibilizer content was 3% by mass relative to the total mass of the masterbatch material and compatibilizer. LLDPE2 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP3530") was then put into two surface layer hoppers. Using a single-screw multilayer extruder, a layer made of LLDPE2, a recycled material-containing layer, and a layer made of LLDPE2 were laminated in this order, and a three-layer film with a thickness of 150 μm was produced with a layer thickness ratio of 1:1:1.

[0167] (Comparative Example A7) Recycled material A9 was fed into a hopper for extruding the recycled material-containing layer, and a single-layer film with a thickness of 100 μm was produced using a single-screw multi-layer extruder.

[0168] (Comparative Example A8) A masterbatch material, which was a melt blend of recycled material A10 and LLDPE1 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2020") in a weight ratio of 1:1, was put into a hopper for extruding the recycled material-containing layer, and a single-layer film with a thickness of 100 μm was produced using a single-screw multi-layer extruder.

[0169] (Comparative Example A9) A masterbatch material, which was a melt-blended mixture of recycled material A11 and LLDPE1 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2020") in a weight ratio of 1:1, was put into a hopper for extruding the recycled material-containing layer, and a single-layer film with a thickness of 100 μm was produced using a single-screw multi-layer extruder.

[0170] <Film Evaluation> The visibility of the film's contents, haze, color difference, internal haze, heat seal strength, and lamination suitability were evaluated using the methods described below.

[0171] (Visibility of Contents) Laminated films were prepared by layering adhesive (film thickness 3 μm), nylon film (manufactured by Unitika Ltd., product name "Emblem OMN", film thickness 15 μm), adhesive (film thickness 3 μm), and PET film (manufactured by Toyobo Co., Ltd., product name "Toyobo Ester Film E5202", film thickness 12 μm) in the following order onto the films of Examples A1 to A10, Comparative Examples A1 to A9, and Reference Example A1. The prepared laminated films were cut to a size of 30 mm x 55 mm to make test pieces. The test pieces were placed on the text on a piece of paper with text written on it, and the visibility of the contents was evaluated by viewing the test pieces from above. The visibility was evaluated using test pieces made with commercially available LLDPE films (manufactured by Tamapoly Co., Ltd., product name "SE62") with thicknesses of 50 μm, 100 μm, or 150 μm as a reference, instead of the films of each example or comparative example. If the appearance of the contents was equivalent to or better than that of a test piece using unused LLDPE film of the same thickness as the sample obtained (however, for Examples A5, Comparative Examples A1 and A3, the thicknesses were 150 μm, 50 μm, and 150 μm, respectively) (e.g., Figure 5a), it was evaluated as "◎" (e.g., Figure 5b). If the appearance was inferior to that of a test piece using commercially available film but still usable, it was evaluated as "〇" (e.g., Figure 5c). If it was not usable, it was evaluated as "×" (e.g., Figures 5d-f).

[0172] (Haze and Color Difference ΔE Measurement) The haze and color difference ΔE of the films in Examples A1 to A10, Comparative Examples A1 to A9, and Reference Example A1 were measured using a spectrochromatic haze meter (manufactured by Nippon Denshoku Industries, Ltd., product name "COH7700", light source: D65). The measurement points were set at a total of nine points on the outermost layer of the film: three points 20 mm inward from the center and both ends in the width direction, and three points 500 mm in the flow direction from each measurement point in the width direction. The average values ​​of the haze and color difference ΔE obtained at the nine points are shown in Tables 1 and 2. Note that the color difference ΔE here is the value relative to the blank measurement, which is performed without the film in place.

[0173] (Internal Haze Measurement) The internal haze of the films in Examples A1 to A10, Comparative Examples A1 to A9, and Reference Example A1 was measured using a spectrochromatic color haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., product name "COH7700"). Silicone oil (100 mL) (manufactured by Green Ace Co., Ltd., product name "Silicone Oil") was applied to both surfaces of the film to fill in the surface irregularities, and measurements were taken at nine points in the same manner as for normal haze measurement. The average value of the nine points was calculated as the internal haze value.

[0174] (Heat seal strength) Two films were overlapped and heat-sealed to a width of 20 mm, leaving 10 mm at the edges. A 10 mm wide test piece was then prepared by cutting off 5 mm from each of the long edges. The heat-seal temperature was varied in 10-degree increments within the range of 120 to 180°C. For each test piece, a Tensilon universal tester RTG-1310 (manufactured by A&D Co., Ltd.) was used to attach the unsealed 10 mm portions to the upper and lower chucks and pull them at 100 mm / min. At this time, regardless of the heat-seal temperature, if the strength obtained was equal to or greater than that of a commercially available film (reference example A1), it was evaluated as "◎"; if the strength was less than that of a commercially available film but the test piece broke, it was evaluated as "〇"; and if interfacial delamination or cohesive failure occurred, it was evaluated as "×".

[0175] (Lamination Suitability) Lamination suitability was evaluated by dry laminating the substrate, Mitsui Chemicals Tohcello's PET film E5202 (film thickness 12 μm), onto the laminate layer side of the sample using an adhesive mixture of DIC Graphics' main agent DIC Dry LX-500, DIC Graphics' curing agent KW75, and Toyo Ink's solvent NC401. The resulting laminate was then visually inspected, and if no defects (areas that appear cloudy) where the adhesive is not interposed between the substrate and the laminate layer were observed, it was marked as "○"; if defects were observed, it was marked as "×".

[0176] The evaluation results for Examples A1 to A10, Comparative Examples A1 to A9, and Reference Example A1 are shown in Tables 3 to 6.

[0177]

[0178]

[0179]

[0180]

[0181] (Evaluation Results) As shown in Tables 3 and 4, it was confirmed that the films of Examples A1 to A10, while containing recycled materials, all received a rating of "○" or "◎" for visibility of contents, heat sealability, and lamination suitability.

[0182] <Preparation of recycled materials> Recycled material A1 as described above was prepared. Recycled material A8 as described above was prepared.

[0183] <Film Preparation> (Example B1) Recycled material A1 was put into a hopper for extruding the recycled material-containing layer, and a film with a thickness of 100 μm was prepared using a single-screw single-layer extruder.

[0184] (Example B2) In a hopper for extruding the recycled material-containing layer, recycled material A1 and LLDPE3 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2040", density 0.918 g / cm³) were added. ３ A film was prepared in the same manner as in Example B1, except that a masterbatch material was added, which was a melt-blended mixture of the two components in a weight ratio of 1:3.

[0185] (Example B3) In a hopper for extruding the recycled material-containing layer, recycled material A1 and LLDPE4 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP1510", density 0.915 g / cm³) were added. ３ A film was prepared in the same manner as in Example B1, except that a masterbatch material was added, which was a melt-blended mixture of the two components in a weight ratio of 1:3.

[0186] (Example B4) In a hopper for extruding the recycled material-containing layer, recycled material A1 and LLDPE5 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP4030", density 0.938 g / cm³) were added. ３ A film was prepared in the same manner as in Example B1, except that a masterbatch material was added, which was a melt-blended mixture of the two components in a weight ratio of 1:3.

[0187] (Example B5) A film was prepared in the same manner as in Example B3, except that recycled material A8 was used.

[0188] (Example B6) In a hopper for extruding the recycled material-containing layer, recycled material A1 and LLDPE3 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2040", density 0.918 g / cm³) were added. ３ A masterbatch material was added, which was a melt blend of ) in a weight ratio of 1:1. Then, using a single-screw multi-layer extruder, LLDPE3 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2040", density 0.918 g / cm³) was extruded so that the layer thickness ratio was 1:1:1. ３ ) and a recycled material-containing layer, and LLDPE3 (manufactured by Prime Polymer Co., Ltd., product name "Evolue SP2040", density 0.918 g / cm³) ３ A three-layer film with a thickness of 100 μm was fabricated so that the layers were stacked in this order.

[0189] (Example B7) A film was prepared in the same manner as in Example B1, except that the film formation rate was adjusted so that the film thickness was 50 μm.

[0190] (Example B8) A film was prepared in the same manner as in Example B1, except that the film formation rate was adjusted so that the film thickness was 200 μm.

[0191] (Comparative Example B1) In a hopper for extruding the recycled material-containing layer, recycled material A1 and LLDPE4 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP1510", density 0.915 g / cm³) are added. ３ A film was prepared in the same manner as in Example B1, except that a masterbatch material was added, which was a melt-blended mixture of the two components in a weight ratio of 1:7.

[0192] (Comparative Example B2) In a hopper for extruding the recycled material-containing layer, recycled material A1 and LLDPE5 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP4030", density 0.938 g / cm³) were added. ３ A film was prepared in the same manner as in Example B1, except that a masterbatch material was added, which was a melt-blended mixture of the two components in a weight ratio of 1:7.

[0193] (Comparative Example B3) In a hopper for extruding the recycled material-containing layer, recycled material A8 and LLDPE3 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2040", density 0.918 g / cm³) were added. ３ A film was prepared in the same manner as in Example B1, except that a masterbatch material was added, which was melt-blended so that the weight ratio of the two components was 7:13.

[0194] (Comparative Example B4) In a hopper for extruding the recycled material-containing layer, recycled material A8 and LLDPE3 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2040", density 0.918 g / cm³) were added. ３ A film was prepared in the same manner as in Example B1, except that a masterbatch material was added, which was a melt-blended mixture of the two components in a weight ratio of 1:15.

[0195] (Comparative Example B5) In a hopper for extruding the recycled material-containing layer, recycled material A8 and LLDPE5 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP4030", density 0.938 g / cm³) were added. ３ Except for adding a masterbatch material that was melt-blended with the following components in a weight ratio of 1:3 and adjusting the film formation rate to achieve a film thickness of 30 μm, film formation was carried out under the same conditions as in Example B1. However, holes occurred during film formation, and it was not possible to produce a film.

[0196] (Comparative Example B6) In a hopper for extruding the recycled material-containing layer, recycled material A8 and LLDPE5 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP4030", density 0.938 g / cm³) were added. ３ A masterbatch material was prepared in the same manner as in Example B1, except that a masterbatch material, which was melt-blended with the following components in a weight ratio of 1:3, was added, and the film deposition rate was adjusted to achieve a film thickness of 220 μm.

[0197] (Reference Example B1) Hopper contains LLDPE3 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2040", density 0.918 g / cm³) ３ The material was introduced, and a film was fabricated using a single-screw single-layer extruder, adjusting the deposition rate to achieve a film thickness of 100 μm.

[0198] (Reference Example B2) Hopper contains LLDPE3 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2040", density 0.918 g / cm³) ３ The material was introduced, and a film was fabricated using a single-screw single-layer extruder, adjusting the deposition speed to achieve a film thickness of 50 μm.

[0199] (Reference Example B3) Hopper contains LLDPE3 (manufactured by Prime Polymer Co., Ltd., product name "Evolu SP2040", density 0.918 g / cm³) ３ The material was introduced, and a film was fabricated using a single-screw single-layer extruder, adjusting the deposition speed to achieve a film thickness of 200 μm.

[0200] <Film Evaluation> The following methods were used to evaluate the film's color difference, density, polyethylene resin content, visibility of contents, sealing properties, blocking resistance, impact resistance, rigidity, and recyclability.

[0201] (Color Difference) The color difference ΔE of the films in Examples B1-B8, Comparative Examples B1-B4 and B6, and Reference Examples B1-B3 was measured using a spectrochromatic color haze meter (manufactured by Nippon Denshoku Industries, Ltd., product name "COH7700", light source: D65). Three measurement points were taken at 100 mm intervals from the center in the width direction in the flow direction, on the outermost layer of the film. The average values ​​of the haze and color difference ΔE obtained at the three points are shown in Tables 7-10. Note that the color difference ΔE here is the value relative to the blank measurement, which is measured without the film in place.

[0202] (Density) The density of the films in Examples B1 to B8, Comparative Examples B1 to B4 and B6, and Reference Examples B1 to B3 was measured using a vacuum density analyzer (MICROTRAC Co., Ltd., product name "BELPYCNO"). Three measurements were taken under the following conditions, and the average value of the density at all three points is shown in Tables 7 to 10. The measurement conditions were as follows: pretreatment: 5 purges, measurement mode: accuracy judgment, number of judgments: 5, accuracy error: 0.02%, equilibrium judgment: 60 Pa, 30 sec.

[0203] (Calculation of the content ratio of polyethylene resin (PE resin) by DSC measurement) Using a differential scanning calorimetry system, the heat of fusion of PE resin and other thermoplastic resins, which are raw materials constituting the recycled material, was measured, as well as the heat of fusion of PE resin and other thermoplastic resins in the films of Examples B1 to B8, Comparative Examples B1 to B6, and Reference Examples B1 to B3. The content ratio of PE resin was calculated from these values.

[0204] DSC measurements were performed under the following conditions: temperature range: 0°C to 300°C, heating rate: 10°C / min. The heat of fusion between 50°C and 140°C was defined as the heat of fusion for PE resin, between 200°C and 230°C as the heat of fusion for nylon (Ny) resin, and between 230°C and 280°C as the heat of fusion for polyethylene terephthalate (PET) resin.

[0205] The percentage of PE resin in the sealant film was calculated using the following formula 1: Percentage of PE resin in sealant film (%) = (x / X) × 100 / [(x / X) + (y / Y) + (z / Z)] .... (Formula 1) [In Formula 1, x, y, and z represent the heat of fusion [mJ / mg] of PE resin, Ny resin, and PET resin obtained by DSC measurement of the sealant film, respectively, and X, Y, and Z represent the heat of fusion [mJ / mg] of virgin PE resin, virgin Ny resin, and virgin PET resin constituting the recycled material, respectively.]

[0206] (Visibility of Contents) Laminated films were prepared by layering adhesive (film thickness 3 μm), nylon film (Unitika, product name "Emblem OMN", film thickness 15 μm), adhesive (film thickness 3 μm), and PET film (Toyobo, product name "Toyobo Ester Film E5202", film thickness 12 μm) in the following order onto the films of Examples B1-B8, Comparative Examples B1-B4, B6, and Reference Examples B1-B3. The prepared laminated films were cut to a size of 30 mm x 55 mm to make test pieces. The test pieces were placed on the text on a piece of paper with text written on it, and the visibility of the contents was evaluated by viewing the test pieces from above. The visibility of the contents was evaluated by comparing the test pieces using the films of Examples B1-B8, Comparative Examples B1-B4, B6 with the test pieces using the film of Reference Examples B1-B3, specifically those using films of the same thickness as the films of Examples B1-B8, Comparative Examples B1-B4, B6. The film of Comparative Example B6 was evaluated based on the film of Reference Example B3. The visibility of the contents was evaluated as follows: "◎" (e.g., Figure 6b) if the appearance was equivalent to or better than the test specimens using the films of Reference Examples B1 to B3 (e.g., Figure 6a); "〇" (e.g., Figure 6c) if the appearance was inferior to the test specimens using the films of Reference Examples B1 to B3 but still usable; and "×" (e.g., Figure 6d to f) if it was not usable.

[0207] (Heat seal strength) Two films were overlapped, heat-sealed to a width of 20 mm, leaving 10 mm at the edges, and 5 mm was trimmed from both long edges to create a 10 mm wide test piece. The heat-seal temperature was varied in 10-degree increments within the range of 120 to 180°C. For each test piece, a Tensilon universal tester RTG-1310 (manufactured by A&D Co., Ltd.) was used, and the unsealed 10 mm portions were attached to the upper and lower chucks and pulled at 100 mm / min. At this time, regardless of the heat-seal temperature, the heat seal strength of the films in Examples B1 to B8 and Comparative Examples B1 to B4 and B6 was evaluated as follows: "◎" if the strength was equal to or greater than that of the reference example films B1 to B3 made only from virgin material and had the same film thickness; "〇" if the strength was less than that of commercially available sealant films but the test piece broke; and "×" if interfacial delamination or cohesive failure occurred. The film of Comparative Example B6 was evaluated based on the film of Reference Example B3.

[0208] (Blocking Resistance) Ten layers of film were stacked and then subjected to a compression test (manufactured by Tester Industries Co., Ltd., product name "CO-201"), with a load of 0.3 MPa applied perpendicularly to each film over a width of 30 mm for two days. After that, the stacked film under load was cut into 30 mm wide x 100 mm long pieces so that the blocked area was 30 mm x 30 mm, and these were used as test specimens. The shear peel strength of the test specimens was measured using a tensile testing machine (manufactured by Shimadzu Corporation, product name "AGS-500NX") with a chuck distance of 50 mm and a tensile speed of 300 mm / min, and the obtained value was defined as the blocking strength. Blocking resistance was evaluated as follows: a blocking strength of 30 [N / 30 mm] or less was marked "○", and a blocking strength exceeding 30 [N / 15 mm] was marked "×".

[0209] (Impact Resistance) The film was cut into 100 mm squares to serve as test specimens. The breaking energy of the test specimens was measured using a film impact tester (manufactured by Toyo Seiki Co., Ltd., product name) in accordance with ASTM D3420. The measurement conditions were a bullet size of 1 / 2 inch and a weighing capacity of 3.0 J. Impact resistance was assessed by comparing the breaking energy of the films in Examples B1 to B8 and Comparative Examples B1 to B4 and B6 with the breaking energy of the films with the same film thickness from Reference Examples B1 to B3. Films with breaking energy equivalent to that of Comparative Examples B1 to B3 were marked with "○", and those with inferior breaking energy were marked with "×". The film of Comparative Example B6 was evaluated based on the film of Reference Example B3.

[0210] (Rigidity) A test specimen was prepared by cutting the film to a width of 15 mm and a length of 100 mm. The rigidity of the test specimen was evaluated using a loop stiffening tester (manufactured by Toyo Seiki Co., Ltd., product name "DA-PC"). The measurement conditions were a loop length of 85 mm, a load range of 50 mN, a compression speed of 3.3 mm / s, and a compression distance of 20 mm. The rigidity was evaluated by comparing the evaluation results of the films of Examples B1 to B8 and Comparative Examples B1 to B4 and B6 with the evaluation results of the films of Reference Examples B1 to B3 with the same film thickness. Films that were equivalent to the evaluation results of Comparative Examples B1 to B3 were marked with "○", and those that were inferior were marked with "×". The film of Comparative Example B6 was evaluated based on the film of Reference Example B3.

[0211] (Recycled Material Content) The recycled material content was calculated from the materials that make up the film, and films with 50% or more recycled material content were evaluated as "◎", films with 15% or more recycled material content as "〇", and films with less than 15% recycled material content as "×". Comparative evaluation with films made only from virgin material was performed using films with the same film thickness.

[0212] The evaluation results for the films of Examples B1 to B8 and Comparative Examples B1 to B4 and B6 are shown in Tables 7 to 10. The "Ethylene-based resin content (mass%)" listed in the tables is calculated based on the fact that components other than thermoplastic resins in recycled materials A1 and A8 are approximately 0% by mass.

[0213]

[0214]

[0215]

[0216]

[0217] As shown in Tables 7-8, it was confirmed that the films of Examples B1-B8, while containing recycled materials, all received a "○" or "◎" rating for visibility of contents, heat sealability, blocking resistance, impact resistance, rigidity, and recycled material content.

[0218] According to the present invention, it is possible to provide a film that contains recycled material, has lamination suitability and transparency, and a laminated film and packaging material equipped therewith. Because the film according to the present invention possesses the above characteristics, it can be used in transparent packaging materials (for example, aluminum layer-less packaging materials) that are suitable for repeated recycling.

[0219] Furthermore, according to the present invention, it is possible to provide a sealant film that contains recycled material while having sufficient heat sealability, lamination suitability, and transparency, as well as a laminated film and packaging material equipped therewith.

[0220] Furthermore, according to the present invention, it is possible to provide a sealant film that contains recycled material while having sufficient transparency and mechanical properties, as well as a laminated film and packaging material using this sealant film.

[0221] Because the sealant film according to the present invention possesses the above-mentioned properties, it can be used in transparent packaging materials (for example, aluminum-layer-less packaging materials) that are suitable for repeated recycling.

[0222] 1...Sealant film, 2...Recycled material-containing layer, 3a, 3b...Recycled material-free layer, 5a, 5b...Adhesive layer, 6...First base film, 7...Printing layer, 8...Second base film, 9...Laminated film.

Claims

A film comprising a recycled material-containing layer containing recycled material including polyolefin resin, A film having a haze of 3% to 25% and a thickness of 50 μm to 200 μm. 　 The film according to claim 1, wherein the internal haze is 1% or more and 15% or less. 　 The film according to claim 1, wherein, when a CIE standard light source D65 with a two-degree field of view is used as the reference light, and the reference light is transmitted through it, the color difference ΔE of the transmitted light in the L*a*b* color space relative to the reference light is 10 or less. 　 The film according to claim 1, wherein the content of polyolefin resin in the recycled material-containing layer is 98% by mass or more based on the total amount of the recycled material-containing layer. 　 The film according to claim 1, which is used as a sealant film. 　 A laminated film comprising the film described in any one of claims 1 to 5. 　 The film further comprises a substrate laminated with an adhesive layer in between, wherein the adhesive layer and the recycled material-containing layer are adjacent to each other. The laminated film according to claim 6, wherein the aforementioned film is a sealant layer. 　 A packaging material comprising the film described in any one of claims 1 to 5. 　 The film further comprises a substrate laminated with an adhesive layer in between, wherein the adhesive layer and the recycled material-containing layer are adjacent to each other. The packaging material according to claim 8, wherein the film is a sealant layer. 　 The packaging material according to claim 8, wherein the amount of plastic material contained in the recycled material is 10% by mass or more, based on the total amount of plastic material in the packaging material. 　 The packaging material according to claim 8, which does not have a layer containing aluminum.

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