Packaging material for deoxidizer and deoxidizer packaging body

Abstract

A packaging material (1) for a deoxidizer, which successively comprises an inner layer (10) containing a thermoplastic resin, an intermediate layer (12) containing an oil-resistant paper, and an outer layer (14) containing a thermoplastic resin, the aforementioned oil-resistant paper not containing fluorine, the packaging material (1) for a deoxidizer having an internal air-permeable hole (H1) that penetrates the aforementioned inner layer (10) and the aforementioned intermediate layer (12), and an external air-permeable hole (H2) that penetrates the aforementioned outer layer.

Description

Technical Field

[0001] This invention relates to packaging materials for deoxidizers and deoxidizer packaging bodies using the same. Background Technology

[0002] For various items such as food, beverages, medicines, medical products, cosmetics, metal products, and electronic products that are easily affected by oxygen and deteriorate or spoil, oxygen-removing agents are used to remove oxygen from the sealed containers containing them in order to prevent oxidative deterioration and enable long-term preservation.

[0003] Oxygen absorbers are used in various ways depending on their intended purpose and method of application. Examples include packaging powdered or tablet-like oxygen absorbers into small pouches using packaging materials. When this oxygen absorber pouch is placed inside a sealed container holding food, the oxygen absorber inside the pouch removes oxygen from the sealed container, thus preventing oxidative deterioration of the food.

[0004] Packaging materials for such oxygen absorbers include those made by laminating sheets of resin, paper, or nonwoven fabric. Packaging materials that consist of layers of resin, paper, and nonwoven fabric are also used. For example, packaging materials that are formed by laminating layers of resin with pre-formed pores with layers of paper or nonwoven fabric are employed. The aim is to ensure air permeability to the outside environment by using a resin layer with pre-formed pores, thereby effectively maximizing the oxygen-absorbing properties of the oxygen absorber.

[0005] Furthermore, while oxygen absorbers are suitable for various foods, when using oxygen absorber packaging for foods containing large quantities of oil, if the packaging material lacks sufficient oil resistance, oil may seep into the packaging material, reducing its oxygen absorption performance due to decreased air permeability; the seeping oil may also damage the appearance of the oxygen absorber packaging. To address these issues, conventional packaging materials have mostly used a lamination of oil-resistant paper containing fluorine-based oil-resistant agents and thermoplastic resin (Patent Document 1).

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2009-35689 Summary of the Invention

[0009] The problem the invention aims to solve

[0010] However, in recent years, the use of fluorinated compounds has been increasingly restricted in Europe (EU) and the United States, and it is believed that such restrictions will become the global benchmark in the future. Therefore, defluorination is also required for packaging materials used as deoxidizers. However, through the research of the inventors, it has been found that fluorine-free oil-resistant paper has problems with deoxidation performance.

[0011] Therefore, the object of the present invention is to provide a deoxidizer packaging material that can exhibit excellent oil resistance and deoxidizer properties without using fluorine-containing oil-resistant paper, and a deoxidizer packaging body using the same.

[0012] Solution for solving the problem

[0013] That is, the main structure of the present invention is as follows.

[0014] [1] A packaging material for deoxidizers, comprising, in sequence: an inner layer containing thermoplastic resin, an intermediate layer containing grease-resistant paper, and an outer layer containing thermoplastic resin.

[0015] The aforementioned oil-resistant paper does not contain fluorine.

[0016] The packaging material for the deoxidizer has: internal vents penetrating the aforementioned inner layer and the aforementioned middle layer, and external vents penetrating the aforementioned outer layer.

[0017] [2] According to the packaging material for deoxidizer described in [1] above, the aforementioned intermediate layer and the aforementioned outer layer are partially fused together.

[0018] [3] The packaging material for deoxidizers described in [1] or [2] above, wherein the aforementioned internal vent is not connected to the aforementioned external vent.

[0019] [4] The packaging material for deoxidizer according to any one of [1] to [3] above, wherein the air permeability resistance of the aforementioned oil-resistant paper according to JIS P8117:2009 is 100 seconds or more.

[0020] [5] A deoxidizer packaging body comprising: a deoxidizer packaging material as described in any one of [1] to [4] above and a deoxidizer packaged in the aforementioned deoxidizer packaging material.

[0021] The effects of the invention

[0022] According to the present invention, it is possible to provide a deoxidizer packaging material that can exhibit excellent oil resistance and deoxidizer properties without using fluorine-containing oil-resistant paper, and a deoxidizer packaging body using the same. Attached Figure Description

[0023] Figure 1 This is a cross-sectional schematic diagram showing one embodiment of the packaging material for the deoxidizer.

[0024] Figure 2 is a schematic cross-sectional view showing another embodiment of the packaging material for a deoxidizer of the present embodiment.

[0025] Figure 3 is a schematic cross-sectional view showing one embodiment of a conventional packaging material for a deoxidizer. Detailed Description of the Embodiments

[0026] Hereinafter, embodiments of the packaging material for a deoxidizer and the deoxidizer package of the present invention will be described in detail.

[0027] It should be noted that in the present specification, the term "A to B" in relation to the description of numerical values means "A or more and B or less" (when A < B) or "A or less and B or more" (when A > B). In addition, in the present invention, combinations of preferred embodiments are more preferred embodiments.

[0028] Furthermore, in the present specification, unless otherwise specified, "(meth)acrylate", "(meth)acryloyl", "(meth)acrylic acid" and the like respectively refer to acrylate and / or methacrylate, acryloyl and / or methacryloyl, acrylic acid and / or methacrylic acid, and the like.

[0029] [Packaging Material for Deoxidizer]

[0030] The packaging material for a deoxidizer of the present invention sequentially includes an inner layer containing a thermoplastic resin, an intermediate layer containing oil-resistant paper, and an outer layer containing a thermoplastic resin, wherein the oil-resistant paper does not contain fluorine, and the packaging material for a deoxidizer has internal vent holes penetrating through the inner layer and the intermediate layer, and external vent holes penetrating through the outer layer.

[0031] Figure 1 and Figure 2 are each a schematic cross-sectional view showing one embodiment of the packaging material for a deoxidizer of the present invention. A packaging material for a deoxidizer (hereinafter sometimes simply referred to as "packaging material") 1 sequentially includes an inner layer 10, an intermediate layer 12, and an outer layer 14, and has internal vent holes H1 penetrating through the inner layer 10 and the intermediate layer 12, and external vent holes H2 penetrating through the outer layer 14. Here, the oil-resistant paper constituting the intermediate layer 12 does not contain fluorine.

[0032] With the above configuration, the packaging material 1 of the present invention can exhibit excellent oil resistance and deoxidizing performance without using fluorine-containing oil-resistant paper.

[0033] The reason why the packaging material of the present invention exerts the above effects is not yet certain, and one of the reasons is considered to be as follows.

[0034] Conventionally, oil-resistant paper containing fluorine (hereinafter sometimes simply referred to as "fluorine-based oil-resistant paper") that has been subjected to oil-resistant treatment using a fluorine-containing oil-resistant agent has been widely used for the intermediate layer.

[0035] However, due to the trend of restricting the use of fluorine compounds in recent years, research is being conducted on the replacement of fluorine-free oil-resistant paper, especially oil-resistant paper that does not use fluorine-containing oil-resistant agents (hereinafter, sometimes simply referred to as "non-fluorine oil-resistant paper").

[0036] The inventors conducted research on the substitution of non-fluorinated oil-resistant paper, and the results show that, as in... Figure 3 In the conventional packaging material 1' shown, when non-fluorinated oleophobic paper is used in the intermediate layer 12', the deoxidation performance is significantly reduced compared to when fluorinated oleophobic paper is used. The reason for this is speculated as follows.

[0037] It is generally believed that the deoxidation performance of packaging materials depends on their air permeability.

[0038] like Figure 3 As shown, in conventional packaging material 1', the internal vent H1' penetrates the inner layer 10 but not the intermediate layer 12' made of grease-resistant paper. In this structure, the air permeability of packaging material 1' is considered to depend primarily on the air permeability of the grease-resistant paper constituting the intermediate layer 12'. The inventors conducted further research and found that non-fluorinated grease-resistant paper has poorer air permeability compared to fluorinated grease-resistant paper.

[0039] Therefore, the inventors conducted repeated and in-depth research, and as a result, they discovered that, Figure 1 and Figure 2 As shown, when non-fluorinated oil-resistant paper is used in the intermediate layer 12, sufficient air permeability can be ensured by forming internal vent holes H1 that penetrate the inner layer 10 and the intermediate layer 12, resulting in excellent deoxidation performance.

[0040] The following is a detailed description of each layer and its composition of the packaging material of this embodiment.

[0041] (Inner layer)

[0042] The inner layer 10 is a layer located on the inner surface of the packaging material 1, and it is a layer containing a thermoplastic resin. There are no particular limitations on the thermoplastic resin; a suitable type can be selected according to the intended use and desired physical properties. Examples of thermoplastic resins include olefin resins such as polyethylene and polypropylene; ethylene-vinyl acetate copolymer resins; and ethylene-(meth)acrylate copolymer resins. From the viewpoint of adhesion, olefin resins are preferred, polyethylene and polypropylene are more preferred, and linear (linear) low-density polyethylene, high-density polyethylene, and unstretched polypropylene are even more preferred. One type can be used alone, or two or more types can be used in combination.

[0043] The lower limit of the melting point of the thermoplastic resin is not particularly limited, but it is preferably 80°C or higher, more preferably 95°C or higher, and even more preferably 110°C or higher. Furthermore, the upper limit of the melting point of the thermoplastic resin is preferably 200°C or lower, more preferably 180°C or lower, and even more preferably 150°C or lower. By using a thermoplastic resin with a melting point of 80°C or higher, even when heat-sealing is performed on the sealed packaging material, there will be no adverse effects such as the leaching of the thermoplastic resin. As a result, powder leakage will not occur, and the deoxidizer can be securely sealed. Furthermore, by using a thermoplastic resin with a melting point below the upper limit, a thorough seal can be achieved in a short time even if the heat-sealing temperature is not set to such a high temperature. More specifically, the melting point of the thermoplastic resin is preferably 80–200°C, more preferably 95–180°C, and even more preferably 110–150°C.

[0044] The inner layer 10 may further contain other components besides thermoplastic resin. Other components that may be used in the inner layer 10 include additives such as stabilizers, lubricants, antistatic agents, antifogging agents, fillers, colorants, plasticizers, and nucleating agents.

[0045] The thickness of the inner layer 10 is not particularly limited, but is preferably 0.5 to 80 μm, more preferably 1 to 60 μm, even more preferably 2 to 50 μm, even more preferably 4 to 40 μm, and even more preferably 15 to 40 μm. By setting the thickness of the inner layer 10 to the above range, sufficient adhesive strength can be obtained by heat sealing in a short time.

[0046] (Middle layer)

[0047] The intermediate layer 12 is a layer containing oil-resistant paper, which imparts certain durability, oil resistance, and breathability to the packaging material, and prevents leakage of the deoxidizer contained in the deoxidizer packaging.

[0048] Oxygen absorber packaging is used for a wide range of products, including food, beverages, pharmaceuticals, medical products, cosmetics, metal products, and electronic products. Therefore, depending on the stored items and environment, it may contain moisture, oil, and other contaminants. In such cases, moisture and oil can penetrate the oxygen absorber from the packaging material, sometimes causing it to deteriorate and reduce its deoxidizing performance, or even contaminating it. However, by incorporating an intermediate layer 12 containing oil-resistant paper, the penetration of moisture and oil can be inhibited, preventing deterioration and contamination of the oxygen absorber.

[0049] In this specification, oil-resistant paper refers to paper or nonwoven fabric that has been given oil resistance. There are no particular limitations on the method of giving oil resistance, and examples include: (1) a method of making the paper or nonwoven fabric itself oil-resistant by filling the mesh of the paper or nonwoven fabric; (2) a method of forming an oil-resistant film by coating the surface of the paper or nonwoven fabric with an oil-resistant agent, an oil-curing agent, etc.; (3) a method of including (impregnating or adding) an oil-resistant agent into the paper or nonwoven fabric, etc.

[0050] There are no particular limitations on the paper material used in greaseproof paper; examples include water-repellent paper, kraft paper, high-quality paper (Western-style paper), and Japanese paper. Similarly, there are no particular limitations on the material of the nonwoven fabric used in greaseproof paper; examples include thermoplastic resins such as polyethylene, polypropylene, polyamide, and polyester. More specifically, examples include linear low-density polyethylene (LLDPE) nonwoven fabrics, polyethylene terephthalate (PET) nonwoven fabrics, composite nonwoven fabrics (PET-PE sheath-core structure, etc.), and TYVEK (a registered trademark, manufactured by DuPont-Asahi Flash Spun Products Co., Ltd.).

[0051] In addition, the oil-resistant paper used in this invention does not contain fluorine.

[0052] In this specification, "fluorine-free" means free from fluorine as an intentionally incorporated component. Therefore, the presence of accidentally contained fluorine is not limited to this. Examples of accidentally contained fluorine include, for instance, fluorine that is slightly introduced as an unavoidable impurity during the manufacturing or cleaning processes. In the fluorine-free greaseproof paper used in this invention, the content of accidentally contained fluorine is, for example, less than 100 ppm.

[0053] A specific example of fluorine-free oil-resistant paper is oil-resistant paper (non-fluorinated oil-resistant paper) that imparts oil resistance to paper or nonwoven fabric without using fluorinated oil-resistant agents. There are no particular limitations on such non-fluorinated oil-resistant paper, as long as it is fluorine-free and possesses a certain degree of oil resistance. Known non-fluorinated oil-resistant papers can be used, such as: (1) non-fluorinated oil-resistant paper that inherently possesses oil resistance by filling the mesh of the paper or nonwoven fabric; (2) non-fluorinated oil-resistant paper that forms an oil-resistant coating by coating the surface of the paper or nonwoven fabric with an oil-resistant non-fluorinated oil-resistant agent, a non-fluorinated agent that cures oil, etc.; (3) non-fluorinated oil-resistant paper that contains (impregnates or adds) an oil-resistant non-fluorinated oil-resistant agent in the paper or nonwoven fabric. From the viewpoint of preventing oil seepage from the interior (inner side of the pores) of the internal vents, the oil-resistant paper described in (3) above is preferred. It should be noted that, as non-fluorinated oil-resistant agents, examples include starch-based oil-resistant agents, acrylic oil-resistant agents, and polyester oil-resistant agents.

[0054] There is no particular limitation on the basis weight of the oil-resistant paper, but it is preferably 5 to 200 g / m². 2 More preferably, it is 15-150 g / m 2 More preferably 25–90 g / m 2 By setting the basis weight of the oil-resistant paper within the above range, sufficient oil resistance and durability can be obtained.

[0055] Furthermore, the air permeability of the greaseproof paper is not particularly limited; for example, the air permeability resistance obtained according to JIS P8117:2009 can be 100 seconds or more. In this invention, by forming internal air vents H1 that penetrate the inner layer 10 and the intermediate layer 12, the air permeability in the thickness direction of the packaging material 1 can be sufficiently ensured, so even greaseproof paper with low air permeability can be used. The upper limit of the above-mentioned air permeability resistance is not particularly limited; for example, it is 100,000 seconds or less, preferably 5,000 seconds or less, and more preferably 2,000 seconds or less. More specifically, the above-mentioned air permeability resistance is, for example, 1,000,000 to 100,000 seconds, preferably 100 to 5,000 seconds, and more preferably 100 to 2,000 seconds.

[0056] The intermediate layer 12 may also contain components other than those constituting the greaseproof paper. Examples of other components that can be used in the intermediate layer 12 include sizing agents (water-resistant agents), water-repellent agents, paper strength enhancers, and dyes. It should be noted that the intermediate layer 12 is preferably composed solely of greaseproof paper.

[0057] The thickness of the intermediate layer 12 is not particularly limited, but is preferably 5 to 300 μm, more preferably 15 to 200 μm, and even more preferably 30 to 150 μm. By setting the thickness of the intermediate layer 12 within the above range, sufficient oil resistance and durability can be obtained.

[0058] (Internal ventilation holes)

[0059] The internal vent H1 is a hole that extends from the surface of the inner layer 10 to the surface of the middle layer 12.

[0060] Conventionally, for example, a method is used to laminate an inner layer 10, which has been pre-treated with openings, to an intermediate layer 12' containing greaseproof paper. Figure 3 However, it is believed that in this structure, the air permeability of packaging material 1' depends on the air permeability of the oil-resistant paper constituting the intermediate layer 12'. Therefore, when using non-fluorinated oil-resistant paper with lower air permeability than fluorinated oil-resistant paper as the intermediate layer 12', there is a problem of decreased air permeability of packaging material 1'.

[0061] In contrast, in the packaging material 1 of the present invention, the internal ventilation holes H1 are not confined to the inner layer 10, but penetrate through the inner layer 10 and the intermediate layer 12. Figure 1 and Figure 2With such internal vents H1, the air permeability of packaging material 1 is not dependent on the air permeability of the greaseproof paper and can be adequately ensured. Therefore, it is believed that even when using non-fluorinated greaseproof paper with lower air permeability than fluorinated greaseproof paper, sufficient air permeability can be ensured as a whole for packaging material 1.

[0062] There are no particular limitations on the configuration of the internal vent H1. (1) The inner layer 10 and the middle layer 12 can be continuously penetrated. (2) The vent through the inner layer 10 can be connected to the vent through the middle layer 12. From the viewpoint of ease of forming the vent, the above (1) is preferred.

[0063] The diameter or pore density of the internal vent H1 can be appropriately adjusted to achieve the desired air permeability (permeability) as a whole as the packaging material 1. Specifically, when using a blade or needle, the adjustment can be made by its shape, penetration direction, configuration, and quantity. When using a laser or electron beam, the adjustment can be made by the piercing conditions such as irradiation voltage, current, irradiation time, and irradiation direction.

[0064] In addition, the shape of the internal vent H1 is not particularly limited, and the cross-section is a circle, triangle, square, ellipse, etc. The longitudinal section is preferably a cone or pyramid shape that tapers from the inner layer 10 toward the middle layer 12 or from the middle layer 12 toward the inner layer 10.

[0065] Furthermore, the diameter of the internal vent H1 is not particularly limited. The diameter φ1 of the internal vent H1 on the surface of the inner layer 10 that does not contact the intermediate layer 12 and the diameter φ2 of the internal vent H1 on the surface of the intermediate layer 12 that does not contact the inner layer 10 can be the same or different. It should be noted that the diameters φ1 and φ2 of the internal vent H1 can be measured by the method described in the embodiments, and are the dimensions (major diameter) of the longest part of the opening diameter.

[0066] The diameters φ1 and φ2 of the internal vent H1 can be appropriately adjusted according to the oil resistance and air permeability required by the packaging material 1, for example, 100 to 750 μm, preferably 150 to 650 μm, and more preferably 200 to 550 μm. By setting them within the above range, both oil resistance and air permeability can be taken into account, and leakage of the deoxidizer inside to the outside can be prevented when the deoxidizer packaging body is made.

[0067] (Outer layer)

[0068] The outer layer 14 is a layer containing thermoplastic resin and having external vent holes H2. The outer layer 14 can be a single-layer film or a multilayer film of two or more layers formed of different materials. The bonding between the outer layer 14 and the intermediate layer 12 is preferably achieved by heat lamination. Therefore, the outer layer 14 is preferably a multilayer film formed of two or more thermoplastic resins with a large difference in melting point. For example, a two-layer film may be formed with a layer of thermoplastic resin with a high melting point, such as polyethylene terephthalate or nylon, on the outer side and a layer of thermoplastic resin with a low melting point on the inner side. The layer with a low melting point preferably contains a heat-sealing material. Examples of heat-sealing materials include, for instance, low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear (linear) low-density polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-methacrylic acid copolymer, ethylene-α-olefin copolymer polymerized using a metallocene catalyst, polypropylene, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, methylpentene polymer, polybutene polymer, acid-modified polyolefin resins (made by modifying polyolefin resins such as polyethylene or polypropylene with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and itaconic acid), polyvinyl acetate resins, poly(meth)acrylic acid resins, and polyvinyl chloride resins. It should be noted that a large difference in melting point between the thermoplastic resin of the inner layer 10 and the thermoplastic resin of the outer layer 14 increases the freedom of heat-sealing conditions (temperature, pressure, time), and is therefore preferred.

[0069] The outer layer 14 may further contain other components besides thermoplastic resin. As other components that can be used in the outer layer 14, the components described as other components of the inner layer 10 may be appropriately used.

[0070] The thickness of the outer layer 14 is not particularly limited, but is preferably 1 to 50 μm, more preferably 2 to 40 μm, even more preferably 4 to 35 μm, and even more preferably 8 to 30 μm. By setting the thickness of the outer layer 14 within the above range, a packaging material with sufficient strength can be obtained, and a packaging material with appropriate flexibility required for bending and other processing in the manufacture of the deoxidizer packaging body described later can be obtained.

[0071] The outer layer 14 can be printed or drawn on the surface by means of gravure printing.

[0072] (External ventilation holes)

[0073] The external vent H2 is a hole that penetrates the outer layer 14.

[0074] The configuration of the internal vent H1 and the external vent H2 is not particularly limited, but it is preferable that the internal vent H1 and the external vent H2 are not interconnected. By not being interconnected, when manufacturing the deoxidizer packaging, it is possible to effectively prevent external components from adhering to the internal deoxidizer, and it is also possible to effectively prevent the internal deoxidizer from leaking to the outside.

[0075] The diameter or pore density of the external vent H2 can be appropriately adjusted to achieve the target air permeability (breathability) as a whole as the packaging material 1. Specifically, the formation method, shape, and pore diameter of the external vent H2 can be appropriately adjusted under the conditions described in the internal vent H1.

[0076] (Properties of packaging materials for deoxidizers)

[0077] The packaging material 1 of the present invention can exhibit excellent oil resistance and deoxidation properties without using fluorine-containing oil-resistant paper.

[0078] The oil resistance of packaging material 1 can be evaluated using the reagent kit number as an indicator, for example, according to J.TAPPI Pulp Test Method No. 41:2000 "Test Method for Oil Repellency of Paper and Paperboard (Reagent Method)". Preferably, the reagent kit number is 2 or higher, and more preferably 4 or higher. Excellent oil resistance is achieved within the above range.

[0079] In addition, packaging material 1 has sufficient air permeability, thus exhibiting excellent deoxygenation performance.

[0080] (Manufacturing method)

[0081] The manufacturing method of the packaging material 1 of the present invention is not particularly limited, but the following preferred examples can be cited as examples.

[0082] As a preferred example, a manufacturing method including the following steps can be listed: a step of preparing a laminate (not shown) that sequentially includes an inner layer 10 and an intermediate layer 12; a step of forming an internal vent H1 by opening the laminate through the inner layer 10 and the intermediate layer 12; and a step of further laminating an outer layer 14 having an external vent H2 on the side of the intermediate layer 12 of the laminate in which the internal vent H1 is formed.

[0083] The method for laminating the inner layer 10 and the intermediate layer 12 is not particularly limited, and known methods can be used. For example, it can be heat lamination or dry lamination. In the case of dry lamination, an adhesive can be used to laminate the layers in the order of inner layer 10 / adhesive layer (not shown) / intermediate layer 12. From the viewpoint of preventing adhesive leakage, it is preferable not to use an adhesive; specifically, heat lamination is preferred compared to dry lamination.

[0084] There are no particular limitations on the methods for creating openings; examples include using a needle, using a cutting tool, using an electron beam, and using a laser.

[0085] Among these methods, from the viewpoint of easily controlling the size and position of the openings, the method of using needles for opening is preferred; from the viewpoint of continuously manufacturing packaging materials for deoxidizers with stable opening density and shape, the method of opening through a cylindrical fixture with needles on the side (hereinafter also referred to as a "needle roller") is more preferred. The diameter of the needles of the aforementioned needle roller is preferably 0.3 to 1.0 mm, more preferably 0.5 to 0.7 mm. By keeping the needle diameter within the aforementioned preferred range, the opening shape is stable, and the adjustment of air permeability becomes easier. In addition, the needle pattern can be appropriately adjusted considering air permeability and oil resistance. Furthermore, when using the aforementioned needle roller, the temperature of the needle roller can be used for opening even at room temperature, but by heating the needle roller within a range not exceeding the melting point of the resin used in the layer to be opened, the opening process can be performed more stably.

[0086] The direction of the perforation treatment (the formation direction of the internal vent H1) can be formed by penetrating the inner layer 10 from the surface of the intermediate layer 12, or by penetrating the intermediate layer 12 from the surface of the inner layer 10. Depending on the formation direction, the shape of the longitudinal section of the internal vent H1 changes, thereby adjusting air permeability and oil resistance. In particular, from the viewpoint of fully penetrating both layers to form appropriate through holes and thus achieving good air permeability, it is preferable to form the perforation by penetrating the inner layer 10 from the surface of the intermediate layer 12.

[0087] The diameter of the internal vent H1 can be appropriately controlled by the fixture for opening the hole, the forming direction, etc. Specifically, when using a conical needle with a tapered tip, when the diameter of the internal vent H1 on the surface of the inner layer 10 that does not contact the intermediate layer 12 is set to φ1, and the diameter of the internal vent H1 on the surface of the intermediate layer 12 that does not contact the inner layer 10 is set to φ2, (1) when the internal vent H1 is formed by penetrating the inner layer 10 from the surface of the intermediate layer 12, the relationship φ1 < φ2 is satisfied. In addition, (2) when the internal vent H1 is formed by penetrating the intermediate layer 12 from the surface of the inner layer 10, the relationship φ1 > φ2 is satisfied.

[0088] The method for laminating the outer layer 14 in the laminate with the perforated treatment is not particularly limited, and known methods can be used. For example, it can be thermal lamination or dry lamination. In the case of dry lamination, an adhesive can be used to laminate the layers in the order of intermediate layer 12 / adhesive layer (not shown) / outer layer 14. From the viewpoint of preventing adhesive leakage, it is preferable not to use an adhesive; specifically, thermal lamination is preferred compared to dry lamination.

[0089] Especially in the case of heat lamination, partial fusion lamination is preferred from the viewpoint of improving breathability. That is, the packaging material 1 of the present invention is preferably formed by partially fusion laminating the intermediate layer 12 and the outer layer 14. In such a packaging material 1, it is believed that gas can move from the internal vent H1 penetrating the inner layer 10 and the intermediate layer 12 through the gap between the intermediate layer 12 and the outer layer 14 to the external vent H2 penetrating the outer layer 14, thereby further improving the breathability of the packaging material 1.

[0090] The method for partial welding is not particularly limited, and known methods can be used. Examples include welding using hot rollers with patterns such as grid patterns or dot patterns. From the viewpoint of improving adhesion, a grid pattern is preferred. Furthermore, from the viewpoint of improving breathability, the welding rate (the area percentage of the welded portion out of the total area of ​​the partially welded region (%)) is, for example, 50% or less, preferably 30% or less, more preferably 20% or less. From the viewpoint of improving adhesion, it is preferably 8% or more, more preferably 12% or more. Specifically, the welding rate for partial welding is, for example, 8-50%, preferably 8-30%, more preferably 12-20%.

[0091] Furthermore, when stacking the molded body having internal vents H1 with the outer layer 14 having external vents H2, it is preferable to arrange them in a manner where the internal vents H1 and external vents H2 are not connected. By ensuring that the internal vents H1 and external vents H2 are not connected, when manufacturing the deoxidizer packaging, it is possible to effectively prevent external components from adhering to the internal deoxidizer, and it is also possible to effectively prevent the internal deoxidizer from leaking to the outside.

[0092] [Oxygen absorber packaging]

[0093] The packaging material 1 of the present invention is suitable for use in the manufacture of oxygen absorber packaging bodies. Specifically, by using the packaging material 1 of the present invention to package oxygen absorbers, oxygen absorber packaging bodies can be obtained.

[0094] That is, the deoxidizer packaging body of the present invention includes the above-mentioned deoxidizer packaging material 1 and the deoxidizer wrapped by the deoxidizer packaging material 1.

[0095] The packaging material 1 of the present invention has excellent oil resistance and air permeability, so the deoxidizer packaging body obtained by using it can exhibit excellent oil resistance and deoxidation performance.

[0096] The method of packaging the deoxidizer using the packaging material 1 of the present invention is not particularly limited, and a suitable method can be adopted appropriately considering the intended use, environment, etc. For example, it is preferable to wrap the deoxidizer in contact with the inner layer 10 of the packaging material 1. As described above, the overlapping portion of the inner layer 10 and the intermediate layer 12 has excellent oil resistance, and the internal vent H1 penetrates through the inner layer 10 and the intermediate layer 12, thus providing excellent air permeability. Therefore, by containing the deoxidizer in contact with the inner layer 10, the intrusion of oil from the outside can be prevented, and sufficient deoxidizing performance can be achieved.

[0097] There are no particular limitations on the type of deoxidizer; any known deoxidizer can be used. For example, the main components of a deoxidizer can include metal powders such as iron powder, organic compounds such as ascorbic acid, and polymers with carbon-carbon double bonds. A deoxidizer does not necessarily have to be a single component; for instance, it can be a deoxidizer formed by combining metal powders such as iron powder with a metal catalyst, water, metal salts, and a carrier.

[0098] Especially for deoxidizers with iron powder as the main component, when oil seeps into the packaging material, the seeping oil may react with the iron powder in the deoxidizer to produce a characteristic odor. To suppress the generation of such an odor, the packaging material for encapsulating iron-based deoxidizers requires good air permeability and high oil resistance. The packaging material 1 of the present invention has good air permeability and exhibits particularly excellent oil resistance, making it particularly suitable for deoxidizers with iron powder as the main component. As a deoxidizer with iron powder as the main component, an iron-based self-reactive deoxidizer comprising iron powder, a metal halide, a carrier, and water is preferred.

[0099] The form of the deoxidizer is not particularly limited, and an appropriate form can be adopted considering the intended use and environment. For example, it can be in powder form or formed into tablets. In the case of powder form, it is preferable to adjust the size and shape of the pores and the layer structure to prevent the powder from leaking out from the internal vent H1 and the external vent H2.

[0100] The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, but includes all the concepts of the present invention and all the ways contained in the claims. Various changes can be made within the scope of the present invention.

[0101] Example

[0102] Hereinafter, this embodiment will be described in detail using examples and comparative examples. However, this embodiment can be appropriately modified as long as it achieves the effects of the present invention. In addition, various measurements and evaluations in the examples and comparative examples are performed as follows.

[0103] (Breathability and resistance)

[0104] The air permeability resistance of oleophobic paper was measured according to JIS P8117:2009 using an Okinawan-type air permeability tester (manufactured by Asahi Seiko Co., Ltd., model EG02). It should be noted that the measurement was performed with the center value of the measurable range set at 2000. Furthermore, the measurement was performed 10 times for each type of oleophobic paper.

[0105] (Opening diameter)

[0106] Regarding the opening diameter, the internal vent holes H1 on the surface of the inner layer of the multilayer film of the packaging material (the surface not in contact with the intermediate layer) are observed, and the length (long axis) of the longest portion of the opening diameter is measured. Measurements are performed using a digital microscope (KEYENCE CORPORATION, VHX-5000) and the distance between two points is determined using the accompanying software. Additionally, measurements are taken on any six internal vent holes H1 on the surface of the inner layer, and the average of the measured values ​​(N=6) is taken as the opening diameter (diameter φ1).

[0107] (Oil resistance)

[0108] The oil resistance was evaluated using the obtained multilayer film of the packaging material, according to J.TAPPI Pulp Test Method No. 41:2000 "Paper and Paperboard – Test Method for Oil Repellency (Reagent Method)". It should be noted that the test solution was applied to the outer layer of the multilayer film of the packaging material.

[0109] The higher the value of the reagent kit number, the higher the oil resistance. In this example, "2" or above is considered qualified.

[0110] (Deoxygenation performance)

[0111] The deoxidation performance is evaluated using a deoxidizer packaging body prepared by the method described in (1) below, and by the method described in (2) below. The preparation method and evaluation method of the deoxidizer packaging body are described in detail below.

[0112] (1) Production of deoxidizer packaging

[0113] The obtained multilayer film of packaging material is bent so that the inner layer is the inner side, and heat-sealed with one side open to produce a small bag with an outer size of 40mm×40mm. After filling it with 1.4g of deoxidizer (an iron-based self-reactive deoxidizer containing iron powder, calcium chloride, sodium chloride, diatomaceous earth impregnated with water, and activated carbon), the open side is heat-sealed to obtain the deoxidizer packaging body.

[0114] (2) Evaluation

[0115] The oxygen absorber package obtained in (1) above was placed together with 250 mL of air into an oxygen barrier bag (size 180 mm × 250 mm, oxygen permeability 0.53 mL / m). 2• 24h • MPa or below (Mocon method, 20℃, 65% RH) and then seal. Next, quickly place each sealed oxygen barrier bag into a constant temperature bath at 25℃.

[0116] Then, the oxygen concentration inside the oxygen barrier bag was measured sequentially at regular intervals, and the changes in oxygen concentration were plotted. The estimated time when the oxygen concentration inside the oxygen barrier bag reached below 0.1% by volume was used as the deoxygenation time for evaluation. It should be noted that, regarding the measurement interval, Examples 1 to 5 were set to every 8 hours starting from 16 hours later, Comparative Examples 1 to 3 were set to every 24 hours, and Comparative Examples 4 and 5 were set to every 4 hours.

[0117] It should be noted that the above oxygen concentration was measured using a gas analyzer (Mocon Dansensor's "Check Mate 3"). The measuring needle was inserted into the oxygen barrier bag through a sampling rubber sheet (25mm×25mm, 2mm thick) pre-adheded to the surface of the oxygen barrier bag, and the measurement was performed automatically.

[0118] In this embodiment, cases where the deoxygenation time exceeds 94 hours (represented as ">94" in the table) are judged as having insufficient deoxygenation capacity.

[0119] (Example 1)

[0120] First, the materials used as the outer, middle and inner layers of the multilayer film that constitutes the packaging material are shown below.

[0121] <Outer layer>

[0122] As the outer layer, a two-layer thin film with the following opening treatment is used.

[0123] First, polyethylene terephthalate (12 μm thick, melting point 265 °C; hereinafter referred to as "PET") and low-density polyethylene (15 μm thick, melting point 110 °C; hereinafter referred to as "PE") are laminated and extruded to obtain a two-layer film (27 μm thick).

[0124] Next, for the obtained two-layer film, an opening process is performed using a needle roller (needle pattern 10.0mm × 10.0mm) to form external vent holes in a manner that penetrates from the surface of PET to PE.

[0125] <Intermediate Layer>

[0126] As an intermediate layer, this is an oil-resistant paper made by impregnating starch-based oil-resistant agents without using fluorinated oil-resistant agents (basis weight 35 g / m²). 2 (Hereinafter referred to as "oil-resistant paper 35").

[0127] <Inner layer>

[0128] As the inner layer, linear low-density polyethylene (30 μm thick, melting point 130 °C; hereinafter referred to as "LLDPE30") is used.

[0129] First, the above-mentioned intermediate layer and the above-mentioned inner layer are stacked and hot-laminated at 200°C to achieve full-surface fusion coating, resulting in a two-layer composite film.

[0130] For this two-layer composite film, an opening process is carried out using a needle roller (needle pattern 5.0mm×5.0mm) to penetrate from the surface of the middle layer to the inner layer, forming internal air pores.

[0131] Then, the outer PE side of the above-mentioned outer layer is placed opposite the middle layer side of the above-mentioned two-layer composite film after the opening treatment, and the layers are stacked with the internal vent holes and the external vent holes not connected. The layers are then heat-laminated at 200°C and partially melt-coated to obtain a multilayer film for packaging materials (packaging material for deoxidizers).

[0132] It should be noted that the above-mentioned portion of the welding uses a hot roller with a diamond-shaped grid pattern. At this time, the welding rate [%] (area of ​​the welded portion [mm²]) is... 2 [×100 / the total area of ​​the partially welded region [mm]] 2 The figure was 16.8%.

[0133] The resulting multilayer film packaging material has a layer structure of outer layer (PET / PE) / middle layer (oil-resistant paper 35) / inner layer (LLDPE 30) (corresponding to Figure 1 In addition, the opening diameter (diameter φ1) of the inner layer surface of the internal vent holes formed on the multilayer film of the obtained packaging material is 323 μm.

[0134] The oil resistance and deoxidation properties of the obtained multilayer packaging film were then evaluated. The results are shown in Table 1.

[0135] (Examples 2 and 3)

[0136] In Examples 2 and 3, oleophobic paper as shown in Table 1 was used instead of oleophobic paper 35 as the intermediate layer. Otherwise, the multilayer film of the packaging material was obtained using the same method as in Example 1. The evaluation results are shown in Table 1.

[0137] (Examples 4 and 5)

[0138] In Examples 4 and 5, grease-resistant paper as shown in Table 1 was used instead of grease-resistant paper 35 as the intermediate layer. Furthermore, when forming internal vents in the two-layer composite film of the intermediate and inner layers, the opening process was performed by penetrating the intermediate layer from the surface of the inner layer. Otherwise, the multilayer film of the packaging material (corresponding to Example 1) was obtained using the same method. Figure 2 The evaluation results are shown in Table 1.

[0139] (Comparative Example 1)

[0140] In Comparative Example 1, the outer PE side was laminated opposite to the middle layer side of the two-layer composite film prepared by the following method. Otherwise, a multilayer film of packaging material (corresponding to Example 1) was obtained using the same method as in Example 1. Figure 3 The evaluation results are shown in Table 1.

[0141] <Fabrication of a 2-layer composite film>

[0142] First, the inner layer (LLDPE30) is perforated using a needle roller (5.0mm × 5.0mm needle pattern).

[0143] Then, the inner layer and the middle layer (oil-resistant paper 35) are stacked with the side that is inserted into the needle roller as the outer side, and hot lamination is performed at 200°C to perform full-surface fusion to obtain a 2-layer composite film.

[0144] The resulting two-layer composite film has a structure in which internal air pores are formed only in the inner layer and do not penetrate the middle layer.

[0145] (Comparative Examples 2-5)

[0146] Comparative Examples 2-5 were obtained using the same method as Comparative Example 1, except that the grease-resistant paper shown in Table 1 was used instead of grease-resistant paper 35 as the intermediate layer. The evaluation results are shown in Table 1.

[0147] [Table 1]

[0148]

[0149] The details of the oil-resistant paper in Table 1 are shown below.

[0150] • Oil-resistant paper 35: Oil-resistant paper impregnated with starch-based oil-resistant agents (oil-resistant paper without fluorinated oil-resistant agents, basis weight 35g / m³) 2 Breathability resistance 340-1700 seconds (average 765 seconds)

[0151] • Oil-resistant paper 50T: Oil-resistant paper made by coating the surface with an agent that cures oil (oil-resistant paper without fluorinated oil-resistant agents, basis weight 50g / m²). 2 Breathability resistance 550-1900 seconds (average 1286 seconds)

[0152] • Oil-resistant paper 50N: Oil-resistant paper that exhibits oil resistance by filling the mesh of paper fibers (oil-resistant paper without fluorinated oil-resistant agents, basis weight 50g / m³) 2 (Breathability and resistance to airflow exceeding 100,000 seconds)

[0153] • F Oil-resistant Paper 38: Oil-resistant paper with added fluorinated oil-resistant agent (oil-resistant paper using fluorinated oil-resistant agent, basis weight 38g / m³) 2 Breathability resistance: 8-10 seconds (average 9 seconds)

[0154] • F Oil-resistant Paper 50: Oil-resistant paper made by coating the surface with a fluorinated oil-resistant agent (oil-resistant paper using a fluorinated oil-resistant agent, basis weight 50g / m²) 2 Breathability resistance 6-9 seconds (average 7 seconds)

[0155] As shown in Table 1, it was confirmed that multilayer films of packaging materials using fluorine-free oil-resistant paper and internal vents penetrating the inner and middle layers can exhibit excellent oil resistance and deoxidation properties (Examples 1-5).

[0156] On the other hand, it was confirmed that although multilayer films of packaging materials using fluorine-free oil-resistant paper, with internal pores formed only in the inner layer and not penetrating the middle layer, have high oil resistance, they do not have sufficient deoxygenation performance (Comparative Examples 1-3).

[0157] It should be noted that even if the internal pores of the multilayer film packaging material using fluorine-containing greaseproof paper are formed only in the inner layer and do not penetrate the middle layer, it can still perform well in terms of deoxygenation performance. However, the use of fluorine-containing greaseproof paper may be limited in the future (Comparative Examples 4 and 5).

[0158] Industrial availability

[0159] The oxygen absorber packaging material and oxygen absorber packaging body of the present invention can be used for a wide range of applications, such as food, cooked food, beverages, pharmaceuticals, health food, etc., regardless of the target product.

[0160] Explanation of reference numerals in the attached figures

[0161] 1 Packaging materials

[0162] 10 Inner Layer

[0163] 12 Intermediate Layers

[0164] 14 Outer layer

[0165] H1 Internal ventilation holes

[0166] H2 External ventilation holes

[0167] φ1 is the diameter of the opening on the surface of the inner layer.

[0168] φ2 Intermediate layer surface opening diameter

Claims

1. A packaging material for deoxidizers, comprising, in sequence: an inner layer containing thermoplastic resin, an intermediate layer containing grease-resistant paper, and an outer layer containing thermoplastic resin. The oil-resistant paper is fluorine-free. The packaging material for the deoxidizer has: internal vents penetrating the inner layer and the middle layer, and external vents penetrating the outer layer. The internal vent is not connected to the external vent. The diameter φ1 of the internal vent hole on the surface of the inner layer that does not contact the intermediate layer and the diameter φ2 of the internal vent hole on the surface of the intermediate layer that does not contact the inner layer satisfy the relationship φ1 < φ2. The oil-resistant paper exhibits its oil resistance by filling the mesh of paper fibers. The inner layer and the intermediate layer are laminated by heat lamination without the use of adhesives, and the intermediate layer and the outer layer are laminated by heat lamination without the use of adhesives.

2. The packaging material for deoxidizers according to claim 1, wherein, The intermediate layer and the outer layer are partially fused together.

3. The packaging material for deoxidizers according to claim 1 or 2, wherein, The oil-resistant paper has an air permeability resistance of over 100 seconds according to JIS P8117:2009.

4. A deoxidizer packaging body comprising: a deoxidizer packaging material according to any one of claims 1 to 3 and a deoxidizer packaged in the deoxidizer packaging material.

Images