Oxygen scavenger package

Abstract

Provided is an oxygen scavenger package comprising an oxygen scavenger and an air-permeable packaging bag (A) in which the oxygen scavenger is accommodated. The air-permeable packaging bag (A) contains no organic fluorine compound and is formed from a laminated packaging material (A1) comprising an outer layer (a1) having through-holes, an air-permeable layer (a2) having air permeability, and an inner layer (a3) having through-holes, in this order. The laminated packaging material (A1) has an air impermeability of 5-25,000 sec, excluding 25,000 sec, the outer layer (a1) and the air-permeable layer (a2) are bonded or fusion-bonded to each other over the entire interface, and the ratio of the number of the through-holes of the outer layer (a1) to the number of the through-holes of the inner layer (a3) is 0.08-40.0.

Description

Oxygen absorber packaging

[0001] The present invention relates to an oxygen absorber package.

[0002] Oxygen absorbers are used to prevent oxidative degradation of products. Examples of products that are susceptible to deterioration or spoilage due to oxygen include food, beverages, pharmaceuticals, medical supplies, cosmetics, metal products, and electronic products. Oxygen absorbers remove oxygen from the sealed containers in which these products are stored, enabling the products to be stored for long periods of time. Oxygen absorbers are used in a variety of ways depending on the purpose and manner of use. For example, oxygen absorbers in powder or tablet form are packaged in a packaging material to form small pouches into oxygen absorber packages. By placing this oxygen absorber package in a sealed container in which food or other items are stored, the oxygen absorber inside the oxygen absorber package removes oxygen from the sealed container, thereby preventing oxidative degradation of the food or other items.

[0003] Packaging materials for such oxygen absorbers include sheets of resin, paper, nonwoven fabric, etc., and laminates of these. Packaging materials with laminated resin layers, paper, or nonwoven fabric layers include packaging materials in which a resin layer with pre-formed ventilation holes is laminated on a paper or nonwoven fabric layer. By using a resin layer with pre-formed ventilation holes, breathability with the outside is ensured, allowing the oxygen absorber to effectively exhibit its oxygen absorbing performance.

[0004] Furthermore, oxygen absorbers are used in a variety of foods, and oxygen absorber packages are also used for foods that contain a lot of oil. In this case, if the packaging material has no or insufficient oil resistance, oil will penetrate the packaging material, causing problems such as a decrease in breathability and a decrease in oxygen scavenging performance, and the soaked oil will damage the appearance of the oxygen absorber package. To solve these problems, conventional packaging materials often use a packaging material made by laminating greaseproof paper containing a fluorine-based oil-resistant agent and a thermoplastic resin (for example, Patent Document 1).

[0005] Furthermore, Patent Document 2 discloses a breathable packaging material in which a breathable plastic film, water-resistant and oil-resistant paper, and another breathable plastic film are laminated together, one of which is partially welded and the other is fully welded, with the aim of controlling the air permeability, increasing the concealing ability against leakage of contents, and improving the feel.

[0006] JP 2009-035689 A JP 2004-082460 A

[0007] In recent years, the use of fluorine-based compounds has been restricted in Europe (EU) and the United States (America), and it is expected that such restrictions will become global standards in the future. Therefore, there is a demand for defluorination of packaging materials for oxygen absorbers as well. However, as described above, when small pouch-shaped oxygen absorbers containing oxygen absorbers made of packaging materials without fluorine-based oil-resistant agents are used for products containing liquids such as food, particularly products containing oil, the liquid penetrates into the packaging material, resulting in problems such as a decrease in breathability and a decrease in oxygen scavenging performance, and the soaked liquid, particularly the soaked oil, can damage the appearance of the oxygen absorber package.

[0008] Furthermore, metal powders such as iron powder, organic compounds such as ascorbic acid, and polymeric compounds having carbon-carbon double bonds used as oxygen absorbers utilize an oxidation reaction to absorb oxygen. However, this reaction can generate heat and water vapor. The steam generated by this oxidation reaction penetrates the packaging material and turns into water droplets. If these droplets remain in the paper layer, problems such as stains and rust due to the water droplets can occur. It is difficult to prevent unintended stains caused by the oxidation reaction of the contents. The present invention was made in light of these circumstances, and the object of the present invention is to provide an oxygen absorber package that can prevent poor appearance due to liquid stains, particularly oil stains, without using a fluorine-based oil-resistant agent in the packaging material, and that can suppress stains caused by steam generated from the oxygen absorber, particularly rust caused by steam in oxygen absorbers containing metals such as iron, and that has high oxygen absorption performance.

[0009] The inventors discovered that the above-mentioned problems can be solved by an oxygen absorber package including a breathable packaging bag made of a laminated packaging material made of a specific material and having a specific air permeability resistance, and thus completed the invention.

[0010] That is, the present invention relates to the following [1] to

[11] . [1] An oxygen absorber package including an oxygen absorber and a breathable packaging bag (A) containing the oxygen absorber, wherein the breathable packaging bag (A) does not contain an organic fluorine compound, and the breathable packaging bag (A) is made of a laminated packaging material (A1) having, in this order, an outer layer (a1) having through holes, a breathable air-permeable layer (a2) and an inner layer (a3) ​​having through holes, the laminated packaging material (A1) having an air resistance of 5 seconds or more and less than 25,000 seconds, the outer layer (a1) and the air-permeable layer (a2) are entirely bonded or entirely welded together, and the ratio of the number of through holes in the outer layer (a1) to the number of through holes in the inner layer (a3) ​​is 0.08 to 40.0. [2] The oxygen absorber package according to [1] above, wherein the air resistance of the air-permeable layer (a2) is less than 400 seconds. [3] The oxygen absorber package according to [1] or [2] above, wherein the breathable layer (a2) is made of greaseproof paper, which has a contact angle of 20 degrees or more with rapeseed oil. [4] The oxygen absorber package according to any one of [1] to [3] above, wherein the breathable layer (a2) is made of greaseproof paper, which does not have a layer made of paraffin wax, polyvinyl alcohol, or acrylic resin on its surface. [5] The oxygen absorber package according to any one of [1] to [4] above, wherein the breathable layer (a2) is made of greaseproof paper, which is obtained by impregnating a base paper made of wood fiber with an oilproof agent solution containing at least one selected from the group consisting of modified starch, amylose, polyvinyl alcohol, and acrylic oilproof agents, and then drying the impregnated base paper. [6] The oxygen absorber package according to any one of [1] to [4] above, wherein the breathable layer (a2) is made of greaseproof paper, which meets the requirements of J. TAPPI Paper Pulp Test Method No. [1] The oxygen absorber package according to any one of [1] to [5], wherein the oxygen absorber is greaseproof paper having a kit value of 1 or more and less than 7 for the oil resistance of the flat surface measured according to ISO 41. [7] The oxygen absorber package according to any one of [1] to [6], wherein the oxygen absorber contains iron powder, and the median diameter of the iron powder is 50 μm or more and 400 μm or less. [8] The oxygen absorber package according to any one of [1] to [7], wherein the thickness of the inner layer (a3) ​​is 20 μm or more and 60 μm or less. [9] The number of through holes in the outer layer (a1) is 0.5 holes / cm ２ More than 60 holes / cm ２The oxygen absorber package according to any one of the above [1] to [8], which is as follows:

[10] The oxygen absorber package according to any one of the above [1] to [9], wherein the breathable packaging bag (A) is formed into a bag shape by heat-sealing the edges together with the inner layer (a3) ​​facing inward, and the width of the heat-sealed portion is 0.3 to 15 mm.

[11] A breathable packaging bag for storing an oxygen absorber, the breathable packaging bag for storing an oxygen absorber comprising a laminated packaging material (A1) that does not contain an organic fluorine compound and has an outer layer (a1) having through holes, a breathable breathable layer (a2) having breathability, and an inner layer (a3) ​​having through holes, in this order, the laminated packaging material (A1) having an air permeability resistance of 5 seconds or more and less than 25,000 seconds, the outer layer (a1) and the breathable layer (a2) are entirely bonded or entirely welded together, and the ratio of the number of through holes in the outer layer (a1) to the number of through holes in the inner layer (a3) ​​is 0.08 to 40.0.

[0011] According to the present invention, it is possible to provide an oxygen absorber package that can prevent poor appearance due to liquid stains, particularly oil stains, without using a fluorine-based oil-resistant agent in the packaging material, and that can suppress stains caused by steam generated from the oxygen absorber, and in particular, rust caused by steam in oxygen absorbers containing metals such as iron, and that has even higher oxygen absorption performance.

[0012] The oxygen absorber package of the present invention is an oxygen absorber package comprising an oxygen absorber and a breathable packaging bag (A) containing the oxygen absorber, wherein the breathable packaging bag (A) does not contain an organic fluorine compound, the breathable packaging bag (A) is made of a laminated packaging material (A1) having, in this order, an outer layer (a1) having through holes, a breathable air-permeable layer (a2) having breathability, and an inner layer (a3) ​​having through holes, the laminated packaging material (A1) has an air resistance of 5 seconds or more and less than 25,000 seconds, the outer layer (a1) and the breathable layer (a2) are entirely bonded or entirely welded together, and the ratio of the number of through holes in the outer layer (a1) to the number of through holes in the inner layer (a3) ​​is 0.08 to 40.0.

[0013] Although the packaging material constituting the breathable packaging bag contained in the oxygen absorber package of the present invention does not contain an organic fluorine compound such as a fluorine-based oil-resistant agent, the oxygen absorber package of the present invention can prevent poor appearance due to liquid stains, particularly oil stains, and can also suppress stains caused by steam generated from the oxygen absorber, particularly rust caused by steam in oxygen absorbers containing metals such as iron, and has high oxygen absorption performance. Although the reasons for this are unclear, it is thought that the following applies: The oxygen absorber package of the present invention adheres the outer layer and the breathable layer to each other by full-surface bonding or full-surface welding, thereby limiting the contact points of liquid penetrating from the outer layer to the perforated portions of the outer layer. This structurally achieves both breathability and oil resistance, suppressing liquid stains, particularly oil stains, while improving oxygen absorption performance. Furthermore, by providing a specific number of through holes in the outer layer relative to the number of through holes in the inner layer, it is thought that steam can escape to the outside of the packaging material while maintaining the above-mentioned performance. Furthermore, as described above, it is believed that high oxygen absorption performance can be achieved by adjusting the number of through-holes in each of the outer and inner layers to a specific ratio and adjusting the air permeability resistance of the entire laminated packaging material to a specific range. Thus, it is believed that the oxygen absorber package of the present invention can prevent poor appearance due to liquid stains, particularly oil stains, even if the packaging material does not use a fluorine-based oil-resistant agent with water and oil repellency. Furthermore, it is believed that stains caused by steam generated from the oxygen absorber, and rust caused by steam, especially in oxygen absorbers containing metals such as iron, can be suppressed, and even higher oxygen absorption performance can be achieved.

[0014] [Oxygen Absorber] The oxygen absorber contained in the oxygen absorber package of the present invention is not particularly limited, but is preferably one containing, as a main component, a substance that has the property of absorbing oxygen by binding with oxygen in a product through a reaction. Examples of substances that have the property of absorbing oxygen include metal powders such as iron powder, organic compounds such as ascorbic acid, and polymeric compounds having a carbon-carbon double bond, with metal powders such as iron powder being more preferred, and iron powder being even more preferred. In other words, it is more preferred that the oxygen absorber contains iron powder (is an iron-based oxygen absorber).

[0015] The iron powder is not particularly limited, but is preferably one with an exposed surface of iron (zero-valent metallic iron), and may have an extremely thin oxide film like a normal metal surface, as long as it does not impair the effects of the present invention. Specifically, reduced iron powder, electrolytic iron powder, atomized iron powder, etc. can be suitably used. Crushed or cut cast iron or the like can also be used. One type of iron powder can be used alone, or two or more types can be used in combination as needed. These iron powders are also readily available commercially and can be used.

[0016] From the viewpoint of oxygen absorption and dust suppression, the median diameter of the iron powder is preferably 10 μm or more and 1000 μm or less, more preferably 30 μm or more and 500 μm or less, even more preferably 50 μm or more and 400 μm or less, and even more preferably 50 μm or more and 300 μm or less. Iron powder having a median diameter within the above range can be obtained by appropriately selecting commercially available iron powder. It can also be obtained, for example, by classification using a sieve corresponding to the desired median diameter. The median diameter of the iron powder can be measured by the method described in the Examples.

[0017] The specific surface area of ​​the iron powder is preferably 0.03 to 0.50 m from the viewpoint of oxygen absorption and dust suppression. ２ / g, more preferably 0.05 to 0.20 m ２ / g.

[0018] The content of iron powder in the oxygen absorbing composition is preferably 15% by mass or more and 75% by mass or less, more preferably 20% by mass or more and 60% by mass or less, and even more preferably 25% by mass or more and 50% by mass or less.

[0019] The oxygen scavenger preferably contains activated carbon, water, a metal halide, and a water-retaining carrier in addition to a substance having oxygen-absorbing properties. The metal halide is preferably at least one selected from the group consisting of alkali metal halides and alkaline earth metal halides, and more preferably contains both alkali metal halides and alkaline earth metal halides. The alkali metal halide is preferably one or more selected from the group consisting of sodium chloride, potassium chloride, potassium bromide, and sodium bromide, and sodium chloride is more preferred. The alkaline earth metal halide is preferably one or more selected from the group consisting of calcium chloride, magnesium chloride, magnesium bromide, and calcium bromide, and calcium chloride is more preferred. Examples of water-retaining carriers include diatomaceous earth, perlite, zeolite, activated alumina, and silica gel.

[0020] In addition to the above components, the oxygen scavenger may contain other components as needed. Examples of other components include swelling agents, alkaline substances, flow improvers, catalysts, odor absorbents, and heat dispersants. In addition to the substance having oxygen-absorbing properties, the oxygen scavenger preferably contains activated carbon, water, metal halide, alkaline substances, and water-retaining carriers.

[0021] [Breathable Packaging Bag (A) and Breathable Packaging Bag for Oxygen Absorber] The breathable packaging bag (A) included in the oxygen absorber package of the present invention does not contain an organic fluorine compound. The breathable packaging bag (A) comprises a laminated packaging material (A1) having, in this order, an outer layer (a1) having through-holes, a breathable breathable layer (a2) having breathability, and an inner layer (a3) ​​having through-holes. The laminated packaging material (A1) has an air resistance of 5 seconds or more and less than 25,000 seconds, the outer layer (a1) and the breathable layer (a2) are fully bonded or fully welded together, and the ratio of the number of through-holes in the outer layer (a1) to the number of through-holes in the inner layer (a3) ​​is 0.08 to 40.0. The absence of an organic fluorine compound in the breathable packaging bag (A) enables it to be used in defluorination.

[0022] The present invention also includes the following breathable packaging bag for an oxygen absorber. Specifically, the breathable packaging bag for an oxygen absorber of the present invention is a breathable packaging bag for storing an oxygen absorber, which does not contain an organic fluorine compound and is made of a laminated packaging material (A1) having, in this order, an outer layer (a1) having through-holes, a breathable breathable layer (a2) having breathability, and an inner layer (a3) ​​having through-holes, the laminated packaging material (A1) having an air resistance of 5 seconds or more and less than 25,000 seconds, the outer layer (a1) and the breathable layer (a2) are fully bonded or fully welded together, and the ratio of the number of through-holes in the outer layer (a1) to the number of through-holes in the inner layer (a3) ​​is 0.08 to 40.0. The breathable packaging bag for an oxygen absorber of the present invention and the breathable packaging bag (A) have the same preferred embodiments. In other words, in the following description, with regard to the breathable packaging bag for oxygen absorbers of the present invention, "breathable packaging bag (A)" or "the breathable packaging bag (A)" will be read as "the breathable packaging bag for oxygen absorbers of the present invention."

[0023] <Laminated packaging material (A1)> The breathable packaging bag (A) is made of a laminated packaging material (A1). The laminated packaging material (A1) has an outer layer (a1) having through holes, a breathable layer (a2) having breathability, and an inner layer (a3) ​​having through holes, in this order, and has an air permeability resistance of 5 seconds or more and less than 25,000 seconds. The outer layer (a1) and the breathable layer (a2) are entirely bonded or entirely welded together, and the ratio of the number of through holes in the outer layer (a1) to the number of through holes in the inner layer (a3) ​​is 0.08 to 40.0.

[0024] (Outer layer (a1)) The outer layer (a1) has through holes. The through holes are ventilation holes (openings) that penetrate the outer layer (a1). When the outer layer (a1) has through holes, sufficient breathability can be ensured and oxygen absorbing performance can be rapidly exhibited. The opening diameter and opening density of the through holes can be appropriately adjusted so that the desired breathability is obtained for the entire packaging material. Specifically, when a blade or needle is used, the adjustment can be made by the shape, penetration direction, arrangement, number, etc. of the blade or needle. When a laser or electron beam is used, the adjustment can be made by the perforation conditions such as the irradiation voltage, current, irradiation time, irradiation direction, etc.

[0025] The shape of the through-holes (openings) may be a circle, a polygon such as a triangle or a square, or an ellipse. From the viewpoints of suppressing liquid staining and breathability, the diameter of the through-holes in the outer layer (a1) is preferably 100 μm or more and 2500 μm or less, more preferably 100 μm or more and 750 μm or less, even more preferably 150 μm or more and 650 μm or less, and even more preferably 200 μm or more and 550 μm or less. By setting the diameter of the through-holes in the outer layer (a1) within the above range, it is possible to achieve both suppression of liquid staining and breathability, while preventing the oxygen absorber inside from leaking to the outside when the oxygen absorber package is made. The diameter of the opening is the dimension (major axis) of the longest part of the opening. The measurement can be performed using an image of the opening of the through-hole taken from directly above under magnification using an optical microscope. More specifically, for example, the distance between two points can be measured using a digital microscope (Keyence Corporation, VHX-5000) and the accompanying software. More specifically, the measurement can be performed using the method described in the Examples.

[0026] The number of through holes in the outer layer (a1) is preferably 0.5 holes / cm from the viewpoint of suppressing liquid staining and breathability. ２ More than 60 holes / cm ２ More preferably, 1 hole / cm or less. ２ More than 60 holes / cm ２ More preferably, 3 holes / cm or less. ２ More than 50 holes / cm ２ and even more preferably 5 holes / cm or less. ２ More than 40 holes / cm ２ and even more preferably 7 holes / cm or less. ２ More than 30 holes / cm ２ and even more preferably 7 holes / cm or less. ２ More than 20 holes / cm ２ and even more preferably 10 holes / cm or less. ２ More than 20 holes / cm ２By setting the number of through holes in the outer layer (a1) within the above range, the strength of the laminated packaging material can be maintained, and when the laminated packaging material is made into an oxygen absorber package, the oxygen absorber inside can be prevented from leaking to the outside while suppressing liquid staining and ensuring breathability. ２ If the thickness is more than this, the reproducibility of the oxygen absorbing performance is improved, and furthermore, liquid is less likely to remain inside the oxygen absorber package, and liquid staining can be suppressed, which is preferable.

[0027] The outer layer (a1) preferably contains polyethylene terephthalate or biaxially oriented polypropylene. The outer layer (a1) may be a monolayer film made of polyethylene terephthalate or biaxially oriented polypropylene, but is preferably a multilayer film having a layer made of polyethylene terephthalate or biaxially oriented polypropylene. The multilayer film preferably has a layer made of a material other than polyethylene terephthalate or biaxially oriented polypropylene on the surface facing the breathable layer (a2). Since thermal lamination is preferably used to bond the outer layer (a1) and the breathable layer (a2), if the outer layer (a1) is a multilayer film, a two-layer film is preferred in which a layer made of a thermoplastic resin with a melting point lower than that of polyethylene terephthalate or biaxially oriented polypropylene is disposed on the breathable layer (a2) side. It is more preferable that the difference between the melting points of polyethylene terephthalate or biaxially oriented polypropylene and the thermoplastic resin is large. A large difference in melting points is preferred because it increases the flexibility of heat-sealing conditions (temperature, pressure, time). Examples of the thermoplastic resin include low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-methacrylic acid copolymer, ethylene-α-olefin copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, methylpentene polymer, polybutene polymer, acid-modified polyolefin resin, polyvinyl acetate resin, poly(meth)acrylic resin, polyvinyl chloride resin, and the like, with low-density polyethylene being preferred.

[0028] The outer layer (a1) may further contain other components in addition to polyethylene terephthalate, biaxially oriented polypropylene, and thermoplastic resin, such as stabilizers, lubricants, antistatic agents, antifogging agents, fillers, colorants, plasticizers, and nucleating agents.

[0029] The thickness of the outer layer (a1) 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 (a1) within the above range, a packaging material having sufficient strength and also having appropriate flexibility required for processing such as folding in the production of an oxygen absorber package described below can be obtained. Letters and drawings can be printed on the surface of the outer layer (a1) by gravure printing or the like.

[0030] (Ventilation layer (a2)) The ventilation layer (a2) is a layer having air permeability. The ventilation layer (a2) is a layer made of so-called greaseproof paper, and provides the packaging bag and packaging material with a certain degree of durability, oil resistance, breathability, etc., while preventing leakage of the oxygen absorber contained in the oxygen absorber package.

[0031] In this specification, greaseproof paper refers to paper or nonwoven fabric that has been given oil resistance. The method for imparting oil resistance when obtaining the greaseproof paper that constitutes the breathable layer (a2) is not particularly limited, and examples include (1) a method of making the paper or nonwoven fabric oil-resistant by tightening the mesh of the paper or nonwoven fabric, (2) a method of forming an oil-resistant coating by applying an oil-resistant agent or an agent that solidifies oil to the surface of the paper or nonwoven fabric, and (3) a method of impregnating (impregnating or adding) an oil-resistant agent to the paper or nonwoven fabric.

[0032] The greaseproof paper used in the breathable layer (a2) does not contain an organic fluorine compound. Therefore, fluorine-based greaseproof paper using a fluorine-containing greaseproof agent is not used in the breathable layer (a2). This makes it possible to respond to defluorination. Specifically, the greaseproof paper used in the breathable layer (a2) is greaseproof paper (non-fluorine-based greaseproof paper) in which oil resistance is imparted to paper or nonwoven fabric without using a fluorine-containing greaseproof agent. Such non-fluorine-based greaseproof paper is not particularly limited as long as it does not contain fluorine and has oil resistance. Examples of such non-fluorine-based greaseproof paper include (1) greaseproof paper in which oil resistance is imparted to the paper or nonwoven fabric by tightening the mesh, (2) greaseproof paper in which an oil-resistant coating is formed by applying an oil-resistant non-fluorine-based greaseproof agent or an oil-solidifying non-fluorine-based agent to the surface of the paper or nonwoven fabric, and (3) greaseproof paper in which an oil-resistant non-fluorine-based greaseproof agent is impregnated or added to the paper or nonwoven fabric. Among these, the greaseproof paper (3) is preferred from the viewpoint of preventing liquid stains.

[0033] Methods for impregnating paper or nonwoven fabric with the non-fluorine-based oil-proofing agent include dipping, size pressing, coating, etc., with dipping being preferred. That is, the breathable layer (a2) is preferably made of greaseproof paper obtained by impregnating paper or nonwoven fabric with the non-fluorine-based oil-proofing agent by dipping.

[0034] More specifically, the greaseproof paper constituting the breathable layer (a2) is preferably greaseproof paper obtained by impregnating a base paper made of wood fiber with an oilproofing agent solution containing at least one selected from the group consisting of modified starch, amylose, polyvinyl alcohol, and acrylic oilproofing agents, followed by drying. That is, the greaseproof paper constituting the breathable layer (a2) is preferably greaseproof paper in which at least one oilproofing agent selected from the group consisting of modified starch, amylose, polyvinyl alcohol, and acrylic oilproofing agents is present throughout the base paper made of wood fiber. Among the oilproofing agents contained in the oilproofing agent solution, at least one selected from the group consisting of modified starch, amylose, polyvinyl alcohol, and acrylic oilproofing agents is preferred, with acrylic oilproofing agents being more preferred. Examples of the base paper made of wood fiber include water-repellent paper, kraft paper, fine paper (Western paper), and Japanese paper.

[0035] The materials of the paper and nonwoven fabric used in the breathable layer (a2) are not particularly limited, but examples of paper materials include water-repellent paper, kraft paper, fine paper (western paper), and Japanese paper. Examples of nonwoven fabric materials used in greaseproof paper include thermoplastic resins such as polyethylene, polypropylene, polyamide, and polyester. More specific examples include linear low-density polyethylene (LLDPE) nonwoven fabrics, polyethylene terephthalate nonwoven fabrics, composite nonwoven fabrics (e.g., polyethylene terephthalate-polyethylene sheath-core structure), and TYVEK (registered trademark, manufactured by DuPont-Asahi Flashspun Products Co., Ltd.).

[0036] On the other hand, the greaseproof paper constituting the breathable layer (a2) preferably does not have a layer made of paraffin wax, polyvinyl alcohol, or acrylic resin on its surface. If these layers are present on the surface to suppress liquid staining, breathability tends to decrease. However, if breathability is ensured despite the presence of these layers on the surface, suppression of liquid staining tends to be insufficient. The presence or absence of a "layer made of paraffin wax, polyvinyl alcohol, or acrylic resin" on the surface can be confirmed by cutting the breathable layer (a2) with a microtome or a sharp blade to allow observation of the cross section of the breathable layer (a2), and then observing the cross section of the breathable layer (a2) with an optical microscope or electron microscope. If a thin film is observed across most or all of the surface between the fibers constituting the breathable layer (a2) and the inner layer (a3) ​​or outer layer (a1), it is determined that a "layer made of paraffin wax, polyvinyl alcohol, or acrylic resin" is present on the surface.

[0037] The basis weight of the breathable layer (a2) is preferably 15 g / m ２ 80g / m or more ２ More preferably, it is 20 g / m or less. ２ 60g / m or more ２ More preferably, it is 30 g / m or less. ２ 55g / m or more ２ and even more preferably 35 g / m or less. ２ 50g / m or more ２By setting the basis weight of the breathable layer (a2) within the above range, sufficient oil resistance and durability can be obtained.

[0038] The air resistance of the breathable layer (a2) is preferably less than 400 seconds, more preferably 200 seconds or less, even more preferably 100 seconds or less, still more preferably 50 seconds or less, and even more preferably 30 seconds or less. There is no particular restriction on the lower limit of the air resistance of the breathable layer (a2), but it is usually 10 seconds or more. By setting the air resistance of the breathable layer (a2) in the above range, sufficient oil resistance and breathability can be achieved at the same time.

[0039] The breathable layer (a2) may contain components other than those constituting the greaseproof paper. Examples of other components that can be used in the breathable layer (a2) include sizing agents (bleed-proofing agents), water-resistant agents, water-repellent agents, paper strength agents, dyes, etc. It is preferable that the breathable layer (a2) is composed only of greaseproof paper.

[0040] The thickness of the breathable layer (a2) 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 breathable layer (a2) within the above range, sufficient oil resistance, water resistance, and durability can be obtained.

[0041] The breathable layer (a2) may have ventilation holes (openings), but preferably has substantially no ventilation holes (openings) because the grease-resistant paper itself is breathable. Even when the breathable layer (a2) has ventilation holes (openings), the diameter of the ventilation holes (openings) is preferably small, and the density of the openings is preferably sparse. By having the breathable layer (a2) have substantially no ventilation holes (openings), leakage of the oxygen scavenger can be prevented, and the intrusion of moisture, oil, etc. can also be suppressed.

[0042] The breathable layer (a2) is made of greaseproof paper, and the greaseproof paper has a Kit value of 1 or more and less than 7 for the oil resistance of its flat surface, measured according to J. TAPPI Paper and Pulp Test Method No. 41. The Kit value is an index showing the oil resistance of greaseproof paper. The Kit value can be determined by a measurement in accordance with J. TAPPI Paper and Pulp Test Method No. 41:2000 "Oil Repellency Test Method for Paper and Paperboard (Kit Method)". The greaseproof paper constituting the breathable layer (a2) has a Kit value of 1 or more and less than 7 for the oil resistance of its flat surface, measured according to J. TAPPI Paper and Pulp Test Method No. 41, preferably 1 or more and less than 7, more preferably 1 or more and 6 or less, even more preferably 1 or more and 5 or less, still more preferably 1 or more and 4 or less, even more preferably 1 or more and 3 or less, and still more preferably 1 or more and 2 or less. The greaseproof paper constituting the breathable layer (a2) has a Kit value of 1 or more and less than 7, more preferably 1 or more and 6 or less, even more preferably 1 or more and 5 or less, still more preferably 1 or more and 4 or less, even more preferably 1 or more and 3 or less, and still more preferably 1 or more and 2 or less. When the oil resistance of the flat portion measured in accordance with J. TAPPI Paper and Pulp Test Method No. 41 is within the above-mentioned range in kit value, the bag can exhibit sufficient water resistance and oil resistance while ensuring sufficient breathability necessary for oxygen removal, thereby preventing the penetration of liquids such as oil and efficiently preventing poor appearance due to liquid stains, etc. In particular, when the outer layer (a1) and the breathable layer (a2) are fully bonded or fully welded together and the greaseproof paper constituting the breathable layer (a2) has an oil resistance of the flat portion measured in accordance with J. TAPPI Paper and Pulp Test Method No. 41 within the above-mentioned range in kit value, the breathable packaging bag can exhibit very excellent water resistance and oil resistance.

[0043] The breathable layer (a2) is made of greaseproof paper, and the greaseproof paper preferably has a contact angle of 20 degrees or more with rapeseed oil. This contact angle is the contact angle of rapeseed oil with the surface of the greaseproof paper used in the breathable layer (a2). The contact angle of rapeseed oil with the breathable layer (a2) is preferably 20 degrees or more, more preferably 30 degrees or more, even more preferably 40 degrees or more, and even more preferably 50 degrees or more. There is no particular limit to the upper limit of the contact angle of rapeseed oil with the breathable layer (a2), but it is usually 90 degrees or less, preferably 80 degrees or less. By setting the contact angle of rapeseed oil with the breathable layer (a2) within the above range, sufficient oil resistance can be exhibited and the penetration of moisture, oil, etc. can be suppressed.

[0044] The breathable layer (a2) is made of greaseproof paper, and the greaseproof paper preferably has a contact angle with water of 61 degrees or more. This contact angle is the contact angle of water with the surface of the greaseproof paper used in the breathable layer (a2). The contact angle of water with the greaseproof paper constituting the breathable layer (a2) is preferably 61 degrees or more, more preferably 75 degrees or more, even more preferably 90 degrees or more, and even more preferably 100 degrees or more. There is no particular upper limit for the contact angle of water with the greaseproof paper constituting the breathable layer (a2), but it is usually 130 degrees or less. By setting the contact angle of water with the greaseproof paper constituting the breathable layer (a2) within the above range, sufficient water resistance and oil resistance can be exhibited, and the penetration of liquids such as moisture can be suppressed.

[0045] (Inner layer (a3)) The inner layer (a3) ​​has through holes. The through holes are ventilation holes (openings) that penetrate the inner layer (a3). When the inner layer (a3) ​​has through holes, sufficient breathability can be ensured and oxygen absorbing performance can be rapidly exhibited. The opening diameter and opening density of the through holes can be appropriately adjusted so that the desired breathability is obtained for the entire packaging material. Specifically, when a blade or needle is used, the adjustment can be made by the shape, penetration direction, arrangement, number, etc. of the blade or needle. When a laser or electron beam is used, the adjustment can be made by the perforation conditions such as the irradiation voltage, current, irradiation time, irradiation direction, etc.

[0046] The shape of the through holes may be a circle, a polygon such as a triangle or a square, or an ellipse. From the viewpoints of suppressing liquid staining and breathability, the diameter of the through holes in the inner layer (a3) ​​is preferably 100 μm or more and 2500 μm or less, more preferably 100 μm or more and 750 μm or less, even more preferably 150 μm or more and 650 μm or less, and even more preferably 200 μm or more and 550 μm or less. By setting the diameter of the through holes in the inner layer (a3) ​​within the above range, it is possible to achieve both suppression of liquid staining and breathability, while preventing the oxygen absorber inside from leaking to the outside when the oxygen absorber package is made. The diameter of the through holes is the dimension of the longest part (major axis) of the through holes. The measurement can be performed using an image of the opening of the through-hole taken from directly above under magnification using an optical microscope. More specifically, for example, the distance between two points can be measured using a digital microscope (Keyence Corporation, VHX-5000) and the accompanying software. More specifically, the measurement can be performed using the method described in the Examples.

[0047] The number of through holes in the inner layer (a3) ​​is preferably 1 hole / cm from the viewpoint of suppressing liquid staining and breathability. ２ More than 60 holes / cm ２ More preferably, 2 holes / cm or less. ２ More than 30 holes / cm ２ More preferably, 4 holes / cm or less. ２ More than 20 holes / cm ２ and even more preferably 6 holes / cm or less. ２ More than 10 holes / cm ２ By setting the number of through holes in the inner layer (a3) ​​within the above range, it is possible to prevent the oxygen absorber inside from leaking to the outside when the oxygen absorber package is made, while suppressing liquid staining and ensuring breathability. In addition, when the number of through holes in the inner layer (a3) ​​is 60 holes / cm or less, ２ If it is less than this, the breathable packaging bag tends to have excellent seal strength.

[0048] The inner layer (a3) ​​preferably contains polyethylene or polypropylene, more preferably polyethylene. The inner layer (a3) ​​more preferably contains linear low-density polyethylene or unstretched polypropylene, more preferably linear low-density polyethylene. The inner layer (a3) ​​is more preferably made of polyethylene or polypropylene, even more preferably polyethylene. The inner layer (a3) ​​is even more preferably made of linear low-density polyethylene or unstretched polypropylene, even more preferably linear low-density polyethylene. One type of polyethylene or polypropylene may be used alone, or two or more types may be used in combination. Hereinafter, the polyethylene or polypropylene constituting the inner layer (a3) ​​will be referred to as the "resin constituting the inner layer (a3)".

[0049] The lower limit of the melting point of the resin constituting the inner layer (a3) ​​is not particularly limited, but is preferably 80°C or higher, more preferably 95°C or higher, and even more preferably 110°C or higher. The upper limit of the melting point of the resin constituting the inner layer (a3) ​​is not particularly limited, but is preferably 200°C or lower, more preferably 180°C or lower, and even more preferably 150°C or lower. When the melting point of the resin constituting the inner layer (a3) ​​is within the above range, problems such as the resin melting out even when heat-sealing is performed during sealing of the packaging material do not occur, and as a result, the oxygen absorber can be securely enclosed without causing powder leakage or the like. Furthermore, sufficient sealing can be achieved in a short time without setting the heat-sealing temperature to a very high temperature.

[0050] The inner layer (a3) ​​may further contain components other than polyethylene and polypropylene, such as stabilizers, lubricants, antistatic agents, antifogging agents, fillers, colorants, plasticizers, and nucleating agents.

[0051] The thickness of the inner layer (a3) ​​is preferably 3 μm or more and 80 μm or less, more preferably 5 μm or more and 60 μm or less, even more preferably 10 μm or more and 60 μm or less, even more preferably 20 μm or more and 60 μm or less, even more preferably 20 μm or more and 50 μm or less, even more preferably 20 μm or more and 40 μm or less, and even more preferably 20 μm or more and 35 μm or less. By setting the thickness of the inner layer (a3) ​​within the above range, sufficient adhesive strength can be obtained with short-term heat sealing. In particular, by setting the thickness of the inner layer (a3) ​​to 60 μm or less, the heat sealing time can be significantly shortened, resulting in excellent productivity.

[0052] (Configuration, Properties, and Manufacturing Method of Laminated Packaging Material (A1)) As described above, the laminated packaging material (A1) has an outer layer (a1) having through holes, a breathable layer (a2) having breathability, and an inner layer (a3) ​​having through holes, in this order; the air resistance of the laminated packaging material (A1) is 5 seconds or more and less than 25,000 seconds; the outer layer (a1) and the breathable layer (a2) are entirely bonded or entirely welded together; and the ratio of the number of through holes in the outer layer (a1) to the number of through holes in the inner layer (a3) ​​is 0.08 to 40.0.

[0053] The laminated packaging material (A1) has an outer layer (a1), a breathable layer (a2), and an inner layer (a3) ​​in this order. The laminated packaging material (A1) is not limited to the three layers and may have other layers such as an adhesive layer, but preferably consists only of the outer layer (a1), the breathable layer (a2), and the inner layer (a3). The laminated packaging material (A1) preferably has the outer layer (a1) on one surface and the inner layer (a3) ​​on the other surface. The outer layer (a1) on the surface becomes the outermost layer of the resulting breathable packaging bag (A) and oxygen absorber package, and is the layer that comes into contact with the atmosphere containing the food product. The inner layer (a3) ​​on the surface becomes the innermost layer of the resulting breathable packaging bag (A) and oxygen absorber package, and is the layer that comes into contact with the atmosphere containing the oxygen absorber. This configuration can prevent liquid stains on the oxygen absorber package, and the oxygen absorber package has high oxygen absorption performance. Furthermore, the laminate packaging material (A1) does not contain an organic fluorine compound. By not containing an organic fluorine compound, the laminate packaging material (A1) can be adapted to defluorination.

[0054] The air resistance of the laminated packaging material (A1) is 5 seconds or more and less than 25,000 seconds. The air resistance of the laminated packaging material (A1) is preferably 5 seconds or more and 20,000 seconds or less, more preferably 5 seconds or more and 15,000 seconds or less, even more preferably 5 seconds or more and 9,000 seconds or less, still more preferably 5 seconds or more and 7,000 seconds or less, still more preferably 5 seconds or more and 5,000 seconds or less, still more preferably 5 seconds or more and 4,000 seconds or less, still more preferably 5 seconds or more and 3,000 seconds or less, still more preferably 5 seconds or more and 2,500 seconds or less, still more preferably 10 seconds or more and 2,500 seconds or less, still more preferably 100 seconds or more and 2,500 seconds or less, still more preferably 300 seconds or more and 2,500 seconds or less, still more preferably 500 seconds or more and 2,500 seconds or less, still more preferably 1,000 seconds or more and 2,500 seconds or less. By setting the air resistance of the laminated packaging material (A1) within the above range, the laminated packaging material (A1) has sufficient breathability while preventing liquid stains, etc. The air resistance of the laminated packaging material (A1) can be appropriately adjusted by adjusting, for example, the thickness of the intermediate layer, the basis weight, the oil-resistant treatment method, the thicknesses of the inner and outer layers, the number of through holes, the hole diameter, the ratio of the number of through holes in the inner layer to the outer layer, etc.

[0055] The laminated packaging material (A1) has its outer layer (a1) and breathable layer (a2) bonded or welded over their entire surfaces. "Full-surface bonding or full-surface welding" refers to the outer layer (a1) and breathable layer (a2) being bonded or welded over the entire area of ​​the portion corresponding to the interior of the resulting breathable packaging bag (A) (inside the heat-welded portion, if the bag is formed by heat-welding the edges together). However, "full-surface bonding or full-surface welding" also includes a small portion that is not bonded or welded, and in practice achieves the same effect as full-surface bonding or full-surface welding. Specifically, the welding rate (the area ratio (%) of the bonded or welded portion to the total area) is preferably 95% or more, more preferably 99% or more, even more preferably 99.5%, and even more preferably 100%, and it is even more preferable that the entire area be bonded or welded.

[0056] The method for laminating each layer is not particularly limited, and known methods can be used. For example, thermal lamination or dry lamination may be used. In the case of dry lamination, each layer may be laminated and bonded using an adhesive. From the viewpoint of preventing leakage of the adhesive, it is preferable not to use an adhesive, and specifically, thermal lamination is preferable to dry lamination. The welding method is not particularly limited, and known methods can be used, for example, a welding method using a heated roll is mentioned.

[0057] The welding temperature during thermal lamination can be appropriately selected taking into consideration the melting point of the resin constituting the inner layer (a3) ​​and the melting point of the resin constituting the layer (welding layer) of the outer layer (a1) in contact with the breathable layer (a2). From the viewpoint of obtaining good adhesion, the welding temperature is preferably higher than the melting point of the resin constituting the inner layer (a3) ​​or the melting point of the resin constituting the layer (welding layer) of the outer layer (a1) in contact with the breathable layer (a2), whichever is higher. Specifically, the welding temperature is preferably 150°C or higher and 280°C or lower, more preferably 170°C or higher and 230°C or lower.

[0058] The ratio of the number of through holes in the outer layer (a1) to the number of through holes in the inner layer (a3) ​​constituting the laminated packaging material (A1) is 0.08 to 40.0. The ratio of the number of through holes in the outer layer (a1) to the number of through holes in the inner layer (a3) ​​is preferably 0.08 to 20.0, more preferably 0.08 to 10.0, even more preferably 0.10 to 10.0, still more preferably 0.20 to 10.0, still more preferably 0.50 to 10.0, still more preferably 0.80 to 10.0, still more preferably 1.00 to 10.0, still more preferably 1.00 to 8.00, still more preferably 1.00 to 5.00, and still more preferably 1.00 to 3.00. By setting the ratio of the number of through-holes in the outer layer (a1) to the number of through-holes in the inner layer (a3) ​​within the above range, the oxygen absorber package obtained has sufficient breathability while preventing liquid stains, etc., and has high oxygen absorption performance. In addition, the occurrence of rust (rust stains) can be suppressed.

[0059] <Characteristics and manufacturing method of breathable packaging bag (A) and oxygen absorber package> As described above, the breathable packaging bag (A) contains an oxygen absorber and does not contain an organic fluorine compound. The breathable packaging bag (A) is made of a laminated packaging material (A1) having an outer layer (a1), a breathable layer (a2), and an inner layer (a3) ​​in this order.

[0060] The breathable packaging bag (A) has a bag-like shape that can accommodate an oxygen absorber. Examples of the breathable packaging bag (A) include a bag-like bag formed by bonding two laminated packaging materials (A1) together with the inner layer (a3) ​​facing inward, or a bag-like bag formed by folding one laminated packaging material (A1) with the inner layer (a3) ​​facing inward and bonding the edges together except for the folded portion, and preferably a bag-like bag formed by folding one laminated packaging material (A1) with the inner layer (a3) ​​facing inward and bonding the edges together except for the folded portion.

[0061] The method for laminating the laminated packaging material (A1) is not particularly limited and can be performed by a known method, such as dry lamination or heat sealing. When the laminated packaging material (A1) is rectangular, examples include a method in which two sheets of the laminated packaging material (A1) are overlapped and the four sides are heat-sealed to form a bag, or a method in which one sheet of the laminated packaging material (A1) is folded and the three sides excluding the folded part are heat-sealed to form a bag. Furthermore, the laminated packaging material (A1) may be formed into a cylindrical shape and both ends and the body of the cylindrical body may be heat-sealed to form a bag.

[0062] Furthermore, when the breathable packaging bag (A) is formed into a bag shape by heat-sealing the edges together with the inner layer (a3) ​​facing inward, the width of the heat-sealed portion is preferably 0.3 to 15 mm, more preferably 3 to 10 mm. The "width of the heat-sealed portion" refers to the shortest length of the heat-sealed portion when a straight line connecting any edge and the center of the bag (the center of gravity of the widest surface) crosses the heat-sealed portion. When the width of the heat-sealed portion is within the above range, the oxygen absorber can be well retained inside the breathable packaging bag (A).

[0063] The method for producing the oxygen absorber package of the present invention is not particularly limited, and a suitable method can be adopted as appropriate, taking into consideration the intended use, environment, etc. of use. It is preferable to place an oxygen absorber in the breathable packaging bag (A) having an opening obtained by the above-mentioned method, and then seal the opening of the breathable packaging bag (A) to obtain an oxygen absorber package. The method for sealing the opening of the breathable packaging bag (A) is not particularly limited, and can be performed by a known method, such as dry lamination or heat sealing. The method for sealing the opening of the breathable packaging bag (A) preferably involves heat sealing the inner layers (a3) ​​present on the inside of the bag to seal the opening of the breathable packaging bag (A).

[0064] The oxygen absorber package obtained in this manner can prevent poor appearance due to liquid stains, etc., even if the packaging material does not use a fluorine-based oil-resistant agent, and has high oxygen absorption performance, so it can be used for a wide range of products such as foods, beverages, pharmaceuticals, medical products, cosmetics, metal products, and electronic products, and is particularly suitable for preserving foods that contain liquids (especially oils, etc.).

[0065] Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, but includes all aspects encompassed by the concept of the present invention and the scope of the claims, and can be modified in various ways within the scope of the present invention.

[0066] The present embodiment will be described in detail below using examples and comparative examples, but the present embodiment can be modified as appropriate as long as the effects of the present invention are achieved. In the examples and comparative examples, "parts" refers to parts by mass unless otherwise specified. Furthermore, various measurements and evaluations in the examples and comparative examples were performed as follows.

[0067] <Outer layer and inner layer> (Aperture diameter) The aperture diameter was measured as the dimension (major axis) of the longest part of the aperture. Measurement was performed using a digital microscope (Keyence Corporation, VHX-5000) and the attached software to measure the distance between two points. Measurement was also performed on six random apertures, and the average of the measured values ​​(N = 6) was taken as the aperture diameter.

[0068] <Ventilation layer> (Air resistance) The air resistance of the ventilation layer was measured using a digital Oken air permeability tester (EG02, manufactured by Asahi Seiko Co., Ltd.) in accordance with JIS P8117:2009. The measurement was performed in a mode in which the median value of the measurable range was 100. The measurement was performed 10 times for the same ventilation layer, and the average value was taken as the air resistance.

[0069] (Oil Resistance (Kit Value) of Greaseproof Paper) The oil resistance (Kit Value) of the flat surface of the greaseproof paper was determined in accordance with J. TAPPI Paper and Pulp Test Method No. 41:2000 "Oil Repellency Test Method for Paper and Paperboard (Kit Method)".

[0070] (Contact angle of grease-resistant paper with rapeseed oil) The contact angle of the grease-resistant paper was measured using a contact angle meter "DMo-502" manufactured by Kyowa Interface Science Co., Ltd. under the following conditions: syringe needle; Teflon (registered trademark) coated needle 22G, liquid volume; 1 μL, analysis method; ellipse fitting, number of repetitions; 3 times, measurement time; 1000 ms after contact with the liquid. The average value of the obtained values ​​was taken as the measurement result. The rapeseed oil used was "Rapeseed Oil Wako Grade 1" manufactured by Fujifilm Wako Pure Chemical Corporation.

[0071] (Contact angle of grease-resistant paper with water) The contact angle of the grease-resistant paper was measured using a contact angle meter "DMo-502" manufactured by Kyowa Interface Science Co., Ltd. under the following conditions: syringe needle: Teflon (registered trademark) coated needle 22G, liquid volume: 1 μL, analysis method: ellipse fitting, number of repetitions: 3, measurement time: 1000 ms after contact with the liquid. The average value of the obtained values ​​was taken as the measurement result. "Distilled water" manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. was used as the water.

[0072] <Laminated packaging material> (Air resistance of laminated packaging material) The air resistance of the laminated packaging material was measured using a digital Oken air permeability tester (EG02, manufactured by Asahi Seiko Co., Ltd.) in accordance with JIS P8117:2009. The measurement was performed in a mode in which the median of the measurable range was 100. The measurement was performed 10 times for each laminated packaging material, and the average value was taken as the air resistance.

[0073] <Oxygen Absorber> (Median Diameter of Iron Powder) The median diameter of the iron powder was measured using a standard sieve conforming to ISO 3310-1:2000 (equivalent to JIS Z8801-1:2006), and the average particle size at a cumulative frequency of 50% (D50) was measured from the weight fraction based on the size of the sieve openings after vibrating for 5 minutes.

[0074] <Evaluation of Oxygen Absorber Package> (Oxygen Absorbing Time) The oxygen absorber packages obtained in the Examples and Comparative Examples were placed in an oxygen barrier bag (size: 220 mm x 300 mm, oxygen permeability: 0.53 mL / m) together with 1,000 mL of air. ２ The bag was sealed in a 24-hour oxygen barrier bag at a pressure of 24 MPa or less (Mocon method, 20°C, 65% RH). The sealed oxygen barrier bag was then promptly placed in a constant temperature bath at 25°C. The oxygen concentration in the oxygen barrier bag was then measured every two hours until the eighth hour, and then every six hours thereafter. The changes in oxygen concentration were plotted, and the estimated time at which the oxygen concentration in the oxygen barrier bag reached 0.1% by volume or less was defined as the oxygen scavenging time. In this test, if the oxygen scavenging time was less than 150 hours, the bag could be practically used as an oxygen absorber package. The shorter the oxygen scavenging time, the better the oxygen absorption performance. The oxygen concentration was measured automatically using a gas analyzer ("Check Mate 3" manufactured by Mocon Dansensor) by inserting a measuring needle into the oxygen barrier bag through a sampling rubber sheet (25 mm x 25 mm, 2 mm thick) previously attached to the surface of the oxygen barrier bag.

[0075] (Liquid stains when in contact with food) Oxygen barrier bag (size 220mm x 300mm, oxygen permeability 0.53mL / m ２One oxygen absorber package obtained in each of the Examples and Comparative Examples was placed in a 24-h MPa or less (Mocon method, 20°C, 65% RH). A pound cake (one from "Seven & i Seven Premium (registered trademark) Liquor-Scented Fruit Pound Cake, 8 pieces") was then placed on top of the oxygen absorber package, bringing the oxygen absorber package and the pound cake into contact. 250 mL of air was then poured into the bag and sealed. The sealed oxygen barrier bag was then placed in a constant temperature bath at 25°C with the oxygen absorber package and pound cake still in contact. After one week, the oxygen barrier bag was opened, the oxygen absorber package was removed, and the appearance was visually inspected to determine whether food stains had occurred. A darker color tone in the food-contact area of ​​the oxygen absorber package compared to the non-food-contact area was considered to be stained. A lack of liquid stains is preferred to prevent poor appearance.

[0076] (Rust Transfer After Oxygen Absorption) The oxygen absorber packages obtained in the Examples and Comparative Examples were placed in an oxygen barrier bag (size: 350 mm x 400 mm, oxygen permeability: 0.53 mL / m) together with 3,000 mL of air. ２ The oxygen barrier bag was sealed in a 24-hour oxygen barrier bag at a pressure of 20°C or less (Mocon method, 20°C, 65% RH). The sealed oxygen barrier bag was then promptly placed in a constant temperature bath at 25°C. After 7 days, the barrier bag was opened and the appearance of the oxygen absorber was observed. The appearance was visually evaluated according to the following criteria. According to the criteria below, A and B indicate that there are no problems in practical use and the appearance of the oxygen absorber package is excellent. On the other hand, according to the criteria below, C and D indicate that the appearance of the oxygen absorber package is problematic in practical use. (Evaluation criteria) A: No rust stains were observed. B: There were a few spot-like rust stains, but the rust spots were spaced apart and independent. C: There were many spot-like rust stains, and some of the rust spots were connected. D: Rust stains were observed over the entire surface. The rust stains were no longer spot-like and had become an irregular pattern.

[0077] (Seal Strength of Breathable Packaging Bag) The oxygen absorber packages (breathable packaging bags) obtained in the Examples and Comparative Examples were cut parallel to the fold at positions 15 mm and 30 mm away from the fold, and then cut in the center perpendicular to the fold to obtain test pieces for measuring seal strength. The test pieces were 15 mm wide strips with a 6 mm wide central seal (welded). Seal strength measurements were performed using a force gauge "RZE-10" manufactured by Aiko Engineering Co., Ltd. One end of the test piece was fixed to a jig attached to the "RZE-10," and the other end was pulled at a speed of approximately 300±20 mm / min until peeling occurred, with the peel direction at approximately 90 degrees relative to the sealed surface (welded surface). The maximum force required for peeling was measured. Measurements were performed on five test pieces, and the average of the maximum force required for peeling was taken as the seal strength of the breathable packaging bag. The greater the seal strength of the breathable packaging bag, the stronger the breathable packaging bag will be, and the stronger it will be, so that it will not open due to an external stimulus and the oxygen absorber will not easily leak to the outside, which is preferable.

[0078] Example 1 (Oxygen Absorber Package) (1) Production of Breathable Packaging Bag The materials used for each layer of the breathable packaging bag are as follows. (Outer Layer) For the outer layer, a two-layer film with the following perforation treatment was used. First, polyethylene terephthalate (thickness 12 μm, melting point 265° C.) and low-density polyethylene (thickness 15 μm, melting point 110° C.) were laminated and extrusion-laminated to obtain a two-layer film. Next, the obtained two-layer film was needle-rolled (needle pattern 2.0 mm x 2.0 mm, number of through holes 50.0 holes / cm) so as to penetrate from the surface of the polyethylene terephthalate to the low-density polyethylene. ２ The film was subjected to perforation treatment using a greaseproof paper (basis weight 40 g / m²) impregnated with an acrylic oil-proofing agent as an greaseproof paper not containing an organic fluorine compound, to prepare a film for an outer layer having through-holes. The diameter of the through-holes was 462 µm. (Air-permeable layer) As the air-permeable layer, an greaseproof paper (basis weight 40 g / m²) impregnated with an acrylic oil-proofing agent was used. ２, air resistance 20 seconds, contact angle with rapeseed oil 78 degrees, contact angle with water 120 degrees, oil resistance (kit value) 2, thickness 66 μm; hereinafter referred to as "oil-resistant paper P"). (Inner layer) A film (thickness 30 μm, melting point 130°C) made of linear low-density polyethylene was attached to a needle roll (needle pattern 1.5 mm × 1.5 mm, number of through holes 44.4 holes / cm). ２ The film was subjected to a perforation treatment using a fluorine-containing polymer film (Fiber-Reinforced Condensate) to prepare a film for an inner layer having through-holes. The diameter of the through-holes was 364 μm.

[0079] (Laminated packaging material) The outer layer film and the grease-resistant paper P for the breathable layer were laminated and heat-laminated at 200°C for full-surface welding to obtain a composite film. Subsequently, the composite film and the inner layer film were similarly heat-laminated at 200°C for full-surface welding to obtain a multilayer film (laminated packaging material). The obtained multilayer film (laminated packaging material) has, in this order, an outer layer (polyethylene terephthalate / low-density polyethylene) with through holes, a breathable breathable layer (grease-resistant paper P), and an inner layer (linear low-density polyethylene) with through holes. The air permeability resistance of the obtained laminated packaging material was also evaluated. The results are shown in Table 1.

[0080] (Breathable Packaging Bag) The multilayer film (laminated packaging material) was folded so that the inner layer was on the inside, and two sides were welded at 140° C. with a width of 6 mm to obtain a breathable packaging bag with one side open.

[0081] (2) Production of Oxygen Absorber Package 4.2 g of oxygen absorber (iron-based self-reacting oxygen absorber containing iron powder (median diameter 100 μm), calcium chloride, sodium chloride, diatomaceous earth impregnated with water, and activated carbon) was filled into the breathable packaging bag, and then one open side was heat-sealed at a width of 6 mm to obtain a small pouch-shaped oxygen absorber package with outer dimensions of 45 mm x 55 mm. The obtained oxygen absorber package was evaluated for oxygen absorption performance (oxygen absorption time), liquid staining upon contact with food, rust transfer after oxygen absorption, and seal strength of the breathable packaging bag. The results are shown in Table 1.

[0082] Examples 2 to 10 and Comparative Examples 1 to 8 (Oxygen Absorber Packages) Laminated packaging materials and oxygen absorber packages were obtained in the same manner as in Example 1, except that the materials used in each layer of the laminated packaging material were changed to those shown in Tables 1 and 2, and the welding method was changed to the method shown in Tables 1 and 2. The air permeability resistance of the obtained laminated packaging materials was evaluated, and the oxygen absorption performance (oxygen absorption time), liquid staining upon contact with food, rust transfer after oxygen absorption, and seal strength of the breathable packaging bag were evaluated for the obtained oxygen absorber packages. The results are shown in Tables 1 and 2. In Table 1 below, the number of through holes used to prepare the outer layer (a1) of Examples 4 and 8 was 5.7 holes / cm. ２ The needle roll of needle pattern 1 had a needle diameter larger than that of the needle rolls with the number of through holes used to form the outer layers of the other examples.

[0083]

[0084]

[0085] In Tables 1 and 2, the grease-resistant papers used in the breathable layers are as follows: Grease-resistant paper P (grease-resistant paper containing no organic fluorine compounds): basis weight 40 g / m ２ , air resistance 20 seconds, contact angle to rapeseed oil 78 degrees, contact angle to water 120 degrees, oil resistance (kit value) 2, thickness 66 μm Grease-resistant paper T (grease-resistant paper not containing organic fluorine compounds): basis weight 40 g / m ２ , air resistance 400 seconds, contact angle to rapeseed oil 39 degrees, contact angle to water 108 degrees, oil resistance (kit value) 7, thickness 60 μm Grease-resistant paper E (grease-resistant paper containing an organic fluorine compound (fluorine-based oil-resistant agent)): basis weight 40 g / m ２ , air resistance 11 seconds, contact angle to rapeseed oil 118 degrees, contact angle to water 133 degrees, oil resistance (kit value) 10, thickness 60 μm

[0086] As shown in Table 1, the oxygen absorber packages of the examples, even though they do not use a fluorine-based oil-resistant agent in the packaging material, are free from liquid stains from food, as are oxygen absorber packages (Comparative Example 1, Table 2) that use a fluorine-based oil-resistant agent in the greaseproof paper of the breathable layer, and can suppress the occurrence of rust (rust stains), demonstrating high oxygen absorption performance. Therefore, the oxygen absorber package of the present invention can prevent poor appearance due to liquid stains and the like without using a fluorine-based oil-resistant agent in the packaging material, and also suppresses the occurrence of stains caused by steam generated from the oxygen absorber, particularly rust (rust stains) caused by steam in oxygen absorbers containing metals such as iron, and has high oxygen absorption performance. Therefore, while complying with defluorination, it can be suitably used in products containing liquids, and is particularly suitable for products containing oils.

Claims

1. A deoxidizer packaging body comprising a deoxidizer and a breathable packaging bag (A) containing the deoxidizer, wherein the breathable packaging bag (A) does not contain an organic fluorine compound, the breathable packaging bag (A) is composed of a laminated packaging material (A1) having an outer layer (a1) with through holes, a breathable layer (a2) having breathability, and an inner layer (a3) with through holes in this order, the air permeability resistance of the laminated packaging material (A1) is 5 seconds or more and less than 25000 seconds, the outer layer (a1) and the breathable layer (a2) are fully adhered or fully welded, and the ratio of the number of through holes in the outer layer (a1) to the number of through holes in the inner layer (a3) is 0.08 to 40.

0.

2. The deoxidizer packaging body according to claim 1, wherein the air permeability resistance of the breathable layer (a2) is less than 400 seconds.

3. The deoxidizer packaging body according to claim 1 or 2, wherein the breathable layer (a2) is made of oil-resistant paper, and the oil-resistant paper has a contact angle of 20 degrees or more with rapeseed oil.

4. The deoxidizer packaging body according to any one of claims 1 to 3, wherein the breathable layer (a2) is made of oil-resistant paper, and the oil-resistant paper does not have a layer made of paraffin wax, polyvinyl alcohol or acrylic resin on its surface.

5. The deoxidizer packaging body according to any one of claims 1 to 4, wherein the breathable layer (a2) is made of oil-resistant paper, and the oil-resistant paper is obtained by impregnating a base paper made of wood fiber with an oil-resistant agent solution containing at least one selected from the group consisting of modified starch, amylose, polyvinyl alcohol and acrylic oil-resistant agent, and then drying.

6. The deoxidizer packaging body according to any one of claims 1 to 5, wherein the breathable layer (a2) is made of oil-resistant paper, and the oil resistance of the flat part measured according to J. TAPPI Paper Pulp Test Method No. 41 is 1 or more and less than 7 in kit value.

7. The deoxidizer packaging body according to any one of claims 1 to 6, wherein the deoxidizer contains iron powder, and the median diameter of the iron powder is 50 μm or more and 400 μm or less.

8. The deoxidizer packaging body according to any one of claims 1 to 7, wherein the thickness of the inner layer (a3) is 20 μm or more and 60 μm or less.

9. The number of through-holes in the outer layer (a1) is 0.5 holes / cm ２ or more and 60 holes / cm ２ or less. The deoxidizer package according to any one of claims 1 to 8.

10. The deoxidizer packaging body according to any one of claims 1 to 9, wherein the breathable packaging bag (A) is formed into a bag shape by heat-sealing the edges with the inner layer (a3) on the inside, and the width of the heat-sealed part is 0.3 to 15 mm.

11. An air-permeable packaging bag for containing a deoxidizer, which is made of a laminated packaging material (A1) having an outer layer (a1) having through-holes, a breathable layer (a2) having air permeability, and an inner layer (a3) having through-holes in this order, does not contain an organic fluorine compound, has an air permeability resistance of 5 seconds or more and less than 25,000 seconds, the outer layer (a1) and the breathable layer (a2) are entirely adhered or entirely welded, and the ratio of the number of through-holes in the outer layer (a1) to the number of through-holes in the inner layer (a3) is 0.08 to 40.

0. The air-permeable packaging bag for a deoxidizer.

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