Oxygen absorbing sealant film

Abstract

To provide an oxygen absorbing sealant film which suppresses an appearance failure by iron powder while maintaining oxygen absorption speed by the iron powder and / or heat sealability by a sealant layer.SOLUTION: As shown in Fig. 1, an oxygen absorbing sealant film 10 has at least a barrier base material layer 12, an oxygen absorption layer 14, and a sealant layer 16 in this order, wherein the oxygen absorption layer 14 and the sealant layer 16 are fused to each other, the oxygen absorption layer 14 contains iron powder, pigment particles and a polyolefin-based resin, and a percentage content of the pigment particles of the sealant layer 16 is 3 mass% or less to the mass of the sealant layer 16.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an oxygen-absorbing sealant film. [Background technology]

[0002] Many proposals have been made to impart oxygen absorbing properties to packaging materials themselves using oxygen-absorbing resin compositions in which oxygen scavengers are dispersed in polyolefin resins. Various inorganic and organic oxygen scavengers are known, and those made of iron powder and an oxidation promoter are preferred from the viewpoints of oxygen absorbing performance, thermal stability to withstand high temperatures during processing, economy, and hygiene. These iron-based oxygen scavengers are generally in granular or powder form.

[0003] Known methods such as co-extrusion lamination, extrusion lamination, and dry lamination are used to produce oxygen-absorbing laminate films containing iron-based oxygen absorbers. The co-extrusion lamination method is a method in which the oxygen-absorbing resin composition constituting the oxygen-absorbing layer and the resin layers constituting the other layers are simultaneously heated and melted to form the laminate. The extrusion lamination method is a method in which only the oxygen-absorbing resin composition is heated and melted and laminated with the resin films constituting the other layers. The dry lamination method is a method in which a single-layer oxygen-absorbing layer film is formed in advance, and then this is bonded to the films constituting the other layers using an adhesive.

[0004] As a method for producing such an oxygen-absorbing laminate film, Patent Document 1 discloses a method for producing an oxygen-absorbing laminate film comprising, from at least the outside, an oxygen barrier layer A / an intermediate layer B / an adhesion-reinforcing layer C / an oxygen absorbing layer D containing an iron-based oxygen scavenger / a sealant layer E, in which the adhesion-reinforcing layer C, the oxygen absorbing layer D containing an iron-based oxygen scavenger or the adhesion-reinforcing layer C, the oxygen absorbing layer D containing an iron-based oxygen scavenger, and the sealant layer E are co-extrusion laminated on the surface of the intermediate layer B. Patent Document 1 discloses that the sealant layer E is a layer made of titanium oxide-containing white unstretched polypropylene. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-260285 Summary of the Invention [Problem to be solved by the invention]

[0006] The oxygen absorbing layer of the iron-based oxygen absorbing film using iron powder has a relatively dark color tone, and when this oxygen absorbing layer is placed in a visible position, it can give a negative aesthetic impression, which is particularly undesirable for food packaging applications.

[0007] As described in Patent Document 1, when a white sealant layer is used as the sealant layer, the appearance of the oxygen absorbing layer can be made less visible. However, the inventors of the present invention have found that, on the other hand, the oxygen absorption rate of the oxygen absorbing layer and / or the heat sealability of the sealant layer may not be sufficiently obtained.

[0008] Therefore, the present invention provides an oxygen-absorbing sealant film that maintains the oxygen absorption rate of the iron powder and / or the heat sealability of the sealant layer while suppressing poor appearance caused by the iron powder. [Means for solving the problem]

[0009] The present inventors have conducted extensive research and found that the above problems can be solved by the following means, and have completed the present invention. That is, the present invention is as follows: <Embodiment 1> The membrane has at least a first skin layer, an oxygen absorbing layer, and a second skin layer in this order, and these are fused to each other, the oxygen absorbing layer contains iron powder, pigment particles, and a polyolefin resin, and the content of the pigment particles is 5% by mass or more with respect to the mass of the oxygen absorbing layer; and The content of inorganic particles in the second skin layer is 3 mass% or less relative to the mass of the second skin layer. Oxygen-absorbing sealant film. <Aspect 2> The content of the iron powder in the oxygen absorbing layer is 20 mass% or more relative to the mass of the oxygen absorbing layer, and The content of the pigment particles in the oxygen absorbing layer is 30% by mass or less with respect to the mass of the oxygen absorbing layer. 2. The oxygen absorbing sealant film of embodiment 1. <Aspect 3> The oxygen-absorbing sealant film according to aspect 1 or 2, wherein the oxygen-absorbing layer has a thickness of 5 μm or more and less than 30 μm. <Aspect 4> The oxygen-absorbing sealant film according to any one of Aspects 1 to 3, wherein the content of the iron powder is 40 mass % or more relative to the mass of the oxygen-absorbing layer. <Aspect 5> The oxygen-absorbing sealant film according to any one of Aspects 1 to 4, wherein the pigment particles are white pigment particles. <Aspect 6> The oxygen-absorbing sealant film according to any one of aspects 1 to 5, wherein the thickness of the first skin layer is greater than 10 μm and less than 50 μm. <Embodiment 7> The oxygen-absorbing sealant film according to any one of embodiments 1 to 6, wherein the thickness of the second skin layer is greater than 10 μm and less than 50 μm. <Embodiment 8> The oxygen-absorbing sealant film according to any one of embodiments 1 to 7, wherein the first skin layer is made of a polyethylene resin. <Aspect 9> The oxygen-absorbing sealant film according to Aspect 8, wherein the polyethylene resin of the first skin layer is linear low-density polyethylene. <Aspect 10> The density of the first skin layer is 0.930 g / cm 3 10. The oxygen absorbing sealant film of embodiment 8 or 9, wherein: <Embodiment 11> The oxygen-absorbing sealant film according to any one of embodiments 1 to 10, which is an inflation film. <Aspect 12> A packaging laminate, An oxygen-absorbing sealant film according to any one of Aspects 1 to 11, and a substrate layer, The substrate layer is laminated on the surface of the first skin layer of the oxygen-absorbing sealant film opposite to the oxygen-absorbing layer. Packaging laminate. <Aspect 13> A packaging container having the packaging laminate described in Aspect 12. <Aspect 14> A packaging container containing contents, the contents being contained in the packaging container described in aspect 13. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide an oxygen-absorbing sealant film that maintains the oxygen absorption rate of the iron powder and / or the heat sealability of the sealant layer while suppressing poor appearance caused by the iron powder. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a cross-sectional side view of the oxygen-absorbing sealant film of the present invention. [Figure 2] FIG. 2 is a cross-sectional side view of the packaging laminate of the present invention. [Figure 3] Fig. 3(a) is a front view of a laminate for evaluation for evaluating heat seal strength, and Fig. 3(b) is a side cross-sectional view taken along line bb in Fig. 3(a). DETAILED DESCRIPTION OF THE INVENTION

[0012] Oxygen-absorbing sealant film As shown in FIG. 1, the oxygen-absorbing sealant film 10 of the present invention is The oxygen absorbing layer 14 contains iron powder, pigment particles, and a polyolefin resin, and the content of the pigment particles is 5% by mass or more relative to the mass of the oxygen absorbing layer. The content of inorganic particles in the second skin layer 16 is 3 mass % or less with respect to the mass of the second skin layer 16 .

[0013] The present inventors have found that the above-mentioned configuration can provide an oxygen-absorbing sealant film that maintains the oxygen absorption rate of the iron powder while suppressing poor appearance due to the iron powder. Without wishing to be bound by theory, it is believed that this is because by including pigment particles in the oxygen-absorbing layer together with the iron powder, the pigment particles can conceal the color of the iron powder without inhibiting oxygen absorption by the iron powder.

[0014] Furthermore, in the above-described configuration, since the content of pigment particles in the second skin layer is low, the influence of the pigment particles on the heat seal strength of the second skin layer can be suppressed, and as a result, the desired heat seal strength can be obtained.

[0015] The oxygen-absorbing sealant film of the present invention can be produced by simultaneously forming and laminating the first skin layer, the oxygen-absorbing layer, and the second skin layer by a multi-layer inflation method. That is, the oxygen-absorbing sealant film of the present invention may be an inflation film.

[0016] In particular, when the oxygen-absorbing sealant film is an inflation film, high heat seal strength is obtained. Without wishing to be bound by theory, this is thought to be because the resin composition constituting the first skin layer, the oxygen-absorbing layer, and the second skin layer is immediately cooled when extruded from the ring-shaped die of the inflation molding machine, and because the oxygen-absorbing layer is supported on the back side by the first skin layer during heat sealing, stress is alleviated, thereby preventing the iron powder from being exposed to the surface.

[0017] Each component of the present invention will be described below.

[0018] First Skin Layer The first skin layer may be a layer containing a polyethylene resin. The first skin layer may be laminated on one side of the oxygen absorbing layer. The first skin layer may also be fused to the oxygen absorbing layer. The first skin layer may be a layer that is bonded to the barrier substrate layer in the packaging laminate described below.

[0019] The thickness of the first skin layer may be greater than 10 μm and less than or equal to 100 μm. The thickness may be greater than 10 μm, greater than or equal to 12 μm, or greater than or equal to 15 μm, or may be less than or equal to 100 μm, less than or equal to 90 μm, less than or equal to 80 μm, less than or equal to 70 μm, less than or equal to 60 μm, less than or equal to 50 μm, less than or equal to 45 μm, less than or equal to 40 μm, less than or equal to 35 μm, less than or equal to 30 μm, less than or equal to 25 μm, or less than or equal to 23 μm.

[0020] (Polyethylene resin) In the present invention and in this specification, a polyethylene-based resin is a resin containing more than 50 mol%, 60 mol% or more, 70 mol% or more, or 80 mol% or more of repeating units of ethylene groups in the main chain of the polymer, and is selected from the group consisting of, for example, non-polar polyethylene-based resins such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), and high-density polyethylene (HDPE); polar polyethylene-based resins such as ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EMAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate copolymer (EMA), ethylene-vinyl acetate copolymer (EVA), carboxylic acid-modified polyethylene, and carboxylic acid-modified ethylene-vinyl acetate copolymer; ionomers; derivatives thereof; and mixtures thereof.

[0021] The density of polyethylene resin is 0.900 g / cm 3 More than 0.905g / cm 3 More than 0.910g / cm 3 More than 0.915g / cm 3 or more, or 0.920 g / cm 3 or more, and may be 0.950 g / cm 3Below, 0.945g / cm 3 Below, 0.940g / cm 3 Below, 0.935g / cm 3 or less, or 0.930 g / cm 3 In particular, the density may be 0.930 g / cm or less. 3 From the viewpoint of heat seal strength, it is preferable that the above-mentioned value is as follows.

[0022] <Oxygen absorption layer> The oxygen absorbing layer contains iron powder, pigment particles, and a polyolefin resin. The oxygen absorbing layer is fused to the second skin layer. The content of the pigment particles in the oxygen absorbing layer is 5% by mass or more.

[0023] The thickness of the oxygen absorbing layer may be 5 to 100 μm. This thickness may be 5 μm or more, 7 μm or more, 10 μm or more, 12 μm or more, or 15 μm or more, or may be 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less, 60 μm or less, 50 μm or less, 45 μm or less, 40 μm or less, 35 μm or less, 33 μm or less, less than 30 μm, 25 μm or less, 20 μm or less, or 18 μm or less. In particular, a thickness of less than 30 μm is preferred from the viewpoint of obtaining good heat seal strength.

[0024] The content of iron powder in the oxygen absorbing layer may be 20 to 80% by mass, and may be 20% by mass or more, 23% by mass or more, 25% by mass or more, 30% by mass or more, 35% by mass or more, 40% by mass or more, 45% by mass or more, 48% by mass or more, or 50% by mass or more, and may be 80% by mass or less, 75% by mass or less, 70% by mass or less, or 65% by mass or less, based on the mass of the oxygen absorbing layer.

[0025] The content of pigment particles in the oxygen absorbing layer may be 3% by mass or more and 30% by mass or less, relative to the mass of the oxygen absorbing layer. This content may be 3% by mass or more, 4% by mass or more, or 5% by mass or more, and may be 30% by mass or less, 25% by mass or less, 20% by mass or less, 15% by mass or less, 10% by mass or less, 9% by mass or less, 8% by mass or less, or 7% by mass or less.

[0026] The oxygen absorbing layer may further contain a pro-oxidant. In this case, the content of the pro-oxidant may be 1 to 30% by mass relative to the mass of the iron powder. This content may be 1% by mass or more, 3% by mass or more, 5% by mass or more, 7% by mass or more, or 10% by mass or more, relative to the mass of the iron powder, and may be 30% by mass or less, 25% by mass or less, 20% by mass or less, or 15% by mass or less.

[0027] The oxygen absorbing layer may further contain an oxygen absorber other than iron powder. In this case, the content of the other oxygen absorber may be 10% by mass or less, 7% by mass or less, 5% by mass or less, 3% by mass or less, 1% by mass or less, or 0% by mass, based on the mass of the oxygen absorbing layer.

[0028] (iron powder) The iron powder may be, for example, reduced iron powder, atomized iron powder, activated iron powder, etc. As such iron powder, commercially available master batches may be used.

[0029] (pigment particles) Examples of pigment particles that can be used include white pigment particles, colored pigment particles, and glitter pigment particles. These pigments may be used alone or in combination.

[0030] Examples of white pigment particles that can be used include titanium dioxide, zinc oxide, lithopone, and white lead.

[0031] As the color pigment particles, known color pigments can be used.

[0032] As the glitter pigment particles, for example, scaly metal pigment particles, pearl pigment particles, etc. can be used.

[0033] As the flaky metal pigment, for example, aluminum powder, particularly aluminum flakes, etc. can be used.

[0034] The pearl pigment particles may be synthetic mica, natural mica, or pigments in which synthetic mica, natural mica, glass, or alumina flakes are coated with titanium oxide or silica.

[0035] (Polyolefin resin) As the polyolefin resin, for example, a polyethylene resin, a polypropylene resin, or the like can be used.

[0036] The polyethylene resin may be any of the polyethylene resins listed for the first skin layer.

[0037] In this specification, a polypropylene-based resin refers to a resin containing more than 50 mol%, 60 mol% or more, 70 mol% or more, or 80 mol% or more of repeating units of propylene groups in the main chain of the polymer, and examples thereof include polypropylene (PP) homopolymer, random polypropylene (random PP), block polypropylene (block PP), chlorinated polypropylene, acid-modified polypropylene, derivatives thereof, and mixtures thereof.

[0038] (prooxidant) As the oxidation promoter, alkali metal chlorides such as sodium chloride, alkaline earth metal oxides such as calcium chloride and magnesium chloride, etc. can be used.

[0039] (Other oxygen absorbers) As oxygen absorbers other than iron powder, iron compounds such as ferrous oxide and ferrous salts, metal halides such as calcium chloride and magnesium chloride, and metal oxides such as cerium oxide can be used.

[0040] <Second Skin Layer> The second skin layer is a skin layer fused to the surface of the oxygen absorbing layer opposite to the first skin layer, and may be made of, for example, a polyolefin resin.

[0041] The second skin layer is substantially free of inorganic particles, and the pigment particle content is 3% by mass or less, based on the mass of the second skin layer. This content may be 2% by mass or less, 1% by mass or less, or 0% by mass. Examples of the inorganic particles include iron powder, oxygen absorbers other than iron powder, pigment particles, and known gas-absorbing inorganic particles such as zeolites, as mentioned in relation to the oxygen absorbing layer.

[0042] The second skin layer may be made of, for example, a polyolefin resin. Examples of the polyolefin resin include polyethylene resin and polypropylene resin. For details of the polyolefin resin, please refer to the descriptions of the first skin layer and the oxygen absorbing layer.

[0043] The resin that makes up the second skin layer may be different from or the same as the resin that makes up the first skin layer.

[0044] When the second skin layer is made of a polyethylene resin, the density of the second skin layer can be determined by referring to the description of the first skin layer.

[0045] The thickness of the second skin layer can be determined by reference to the thickness of the first skin layer. The thickness of the second skin layer may be the same as or different from the thickness of the first skin layer, but is preferably greater than 10 μm from the viewpoint of heat seal strength, and is preferably less than 50 μm from the viewpoints of increasing the oxygen absorption rate and improving ease of opening when used as a package.

[0046] <<Packaging laminate>> The packaging laminate 20 of the present invention is The oxygen-absorbing sealant film 10 and the barrier substrate layer 22 are included, The barrier substrate layer 22 is laminated to the surface of the first skin layer 12 of the oxygen-absorbing sealant film 10 opposite to the oxygen-absorbing layer 14 .

[0047] The barrier substrate layer 22 and the first skin layer 12 may be bonded to each other via, for example, an adhesive layer 24. Although not shown, the packaging laminate of the present invention may further have a hard substrate layer, in particular a hard resin substrate layer.

[0048] The packaging laminate of the present invention may be, for example, a laminate for a packaging bag, a laminate for a laminate tube, a laminate for a lid material, or a laminate for a packaging container.

[0049] In particular, when the packaging laminate of the present invention is a laminate for a laminate tube, it is preferable from the viewpoint of obtaining a laminate tube that another sealant layer be provided on the surface opposite to the second skin layer. As the other sealant layer, the resin constituting the second skin layer can be used.

[0050] When the packaging laminate of the present invention is a lid material laminate, the second skin layer may be easy-peelable or may be strongly adhesive, i.e., a sealant layer for opening by means other than peeling from the container, such as cutting, and the packaging laminate of the present invention is particularly useful when it has strongly adhesive properties.

[0051] The form of the packaging container laminate is not particularly limited and may be, for example, a laminate for blister containers. In particular, when the packaging laminate of the present invention is a laminate for blister containers, it is preferable that the packaging laminate further has a reinforcing layer.

[0052] <Barrier substrate layer> The barrier substrate layer may be composed of at least one of a soft substrate layer and a hard substrate layer, and a barrier layer. The soft substrate layer, the hard substrate layer, and the barrier layer may each be present in one or more layers, and these layers may be laminated via an adhesive layer.

[0053] (Soft base material layer) The term "flexible substrate layer" refers to a substrate layer having flexibility, particularly a substrate layer having a thickness of 100 μm or less. The thickness of the flexible substrate layer is not particularly limited as long as it does not impair flexibility, and may be, for example, 7 μm or more and 100 μm or less. The thickness may be 7 μm or more or 10 μm or more, or may be 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less, 60 μm or less, 55 μm or less, 50 μm or less, 45 μm or less, 40 μm or less, 35 μm or less, 30 μm or less, 25 μm or less, 20 μm or less, or 15 μm or less.

[0054] As such a substrate layer, a soft resin substrate layer, a soft paper substrate layer, or the like can be used.

[0055] (Soft resin base material layer) The soft resin substrate layer may be composed of a thermoplastic resin having excellent impact resistance, abrasion resistance, etc., such as a vinyl resin, a polyester resin, a polyamide resin, etc. The soft resin substrate layer may be a single layer or a laminate.

[0056] Examples of vinyl resins include polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene, polytetrafluoroethylene, and polyacrylonitrile (PAN).

[0057] Examples of polyester resins include polyethylene terephthalate (PET) and polybutylene terephthalate.

[0058] Examples of polyamide resins include nylons such as Nylon (registered trademark) 6 and Nylon MXD6.

[0059] As the laminate for the soft resin substrate layer, a laminate of PVF / PET / PVF, for example, a known laminate called TPT, can be used.

[0060] The thickness of the soft resin substrate layer is preferably 7 μm or more or 10 μm or more from the viewpoint of the mechanical strength of the packaging laminate, and may be 55 μm or less, 50 μm or less, 45 μm or less, 40 μm or less, 35 μm or less, 30 μm or less, 25 μm or less, 20 μm or less, or 15 μm or less.

[0061] The resin constituting the soft resin substrate layer may be one type or a blend of two or more types, and additives for imparting functionality, etc. may be blended as necessary.

[0062] The soft resin substrate layer is preferably produced from a preformed film. The film to be the soft resin substrate layer may be a film formed from the above-mentioned resins, etc., and may be unstretched or uniaxially or biaxially stretched. Among these, a biaxially stretched film is preferred.

[0063] (Soft base layer: Soft paper base layer) As the soft paper substrate layer, coated paper, art paper, etc. may be used.

[0064] The basis weight of the paper that makes up the soft paper base layer is 10 g / m 2 More than 30g / m 2 or more, or 50 g / m 2 or more, and may be 200 g / m 2 Below 150g / m 2 or less than 100g / m 2 It may be the following:

[0065] (Hard base material layer) The term "hard substrate layer" refers to a substrate layer having hard properties, particularly a substrate layer having a thickness of more than 100 μm. The thickness of the hard substrate layer is not particularly limited as long as it does not impair the hard properties, and may be, for example, more than 100 μm and 3 mm or less. The thickness may be more than 100 μm, 150 μm or more, 200 μm or more, 250 μm or more, or 300 μm or more, or may be 3 mm or less, 2 mm or less, 1 mm or less, 900 μm or less, 800 μm or less, 700 μm or less, 600 μm or less, or 500 μm or less.

[0066] As the hard substrate layer, for example, a hard resin substrate layer, a hard paper substrate layer, or a hard inorganic substrate layer can be used.

[0067] (Hard base material layer: hard resin base material layer) As the hard resin substrate layer, for example, a polyvinyl chloride layer, a polycarbonate layer, a polypropylene layer, or the like can be used.

[0068] (Hard base layer: hard paper base layer) As the hard paper substrate layer, for example, paperboard, corrugated cardboard, etc. can be used.

[0069] (Hard base material layer: hard inorganic base material layer) As the hard inorganic substrate layer, for example, a glass layer or the like can be used.

[0070] (barrier layer) The barrier layer can be made of a material that can prevent moisture, organic gases, inorganic gases, etc. from permeating from the base layer side to the sealant layer side and / or oxygen from permeating from the outside, thereby preventing the oxygen absorbing layer from becoming inactive. Examples of such barrier layers include a simple metal foil layer such as copper foil or aluminum foil, an alloy foil layer such as stainless steel foil, an inorganic vapor deposition film such as a silica vapor deposition film, an alumina vapor deposition film, an aluminum vapor deposition film, or a silica-alumina binary vapor deposition film, a barrier resin layer such as an ethylene-vinyl alcohol copolymer (EVOH), a cyclic olefin polymer (COP), or a cyclic olefin copolymer (COC), or an organic coating film such as a polyvinylidene chloride coating film, a polychlorotrifluoroethylene coating film, or a polyvinylidene fluoride coating film.

[0071] In particular, among the above barrier layers, the inorganic vapor deposition film and the organic coating film can act as a transparent barrier layer.

[0072] When an inorganic vapor deposition film or an organic coating film is used as the barrier layer, the thickness of the barrier layer is preferably 100 nm or more, 200 nm or more, 300 nm or more, 500 nm or more, 700 nm or more, or 1 μm or more from the viewpoint of ensuring strength and barrier properties, and is preferably 5 μm or less, 4 μm or less, 3 μm or less, or 2 μm or less from the viewpoint of reducing the thickness of the entire packaging laminate.

[0073] When a metal foil layer or a barrier resin layer is used as the barrier layer, the thickness of the barrier layer is preferably 5 μm or more, or 7 μm or more, from the viewpoint of ensuring strength and barrier properties, and is preferably 50 μm or less, 45 μm or less, 40 μm or less, 35 μm or less, 30 μm or less, 25 μm or less, 20 μm or less, 15 μm or less, or 10 μm or less, from the viewpoint of reducing the thickness of the entire packaging laminate.

[0074] (Adhesive layer) As the adhesive layer, for example, a dry laminating adhesive, a hot laminating adhesive, or the like can be used.

[0075] Other layers The oxygen-absorbing sealant film of the present invention may optionally have other layers, such as an adhesive layer between the barrier substrate layer and the first skin layer, and an anchor coat layer.

[0076] 《Packaging container》 The packaging container of the present invention has the oxygen-absorbing sealant film described above.

[0077] The packaging container of the present invention may be a content-containing packaging container having contents accommodated in the packaging container.

[0078] The packaging container of the present invention may be a packaging bag, a laminated tube, or a container with a lid.

[0079] In particular, the packaging bag of the present invention comprises one or more of the above-mentioned oxygen-absorbing sealant films, and A portion of one or more sheets of oxygen-absorbing sealant film is heat-sealed to another portion of the oxygen-absorbing sealant film or to another film to form a bag, where the other film may be another oxygen-absorbing sealant film or may be a film other than the oxygen-absorbing sealant film.

[0080] One embodiment of the packaging bag of the present invention may be a bag having at least a peripherally sealed portion in which two films are heat-sealed facing each other at their peripheral edges. The peripherally sealed portion can be obtained by a method including placing two films facing each other and heat-sealing at least a portion of the peripheral edges of these films. Examples of such packaging bags include stand-up pouches, retort pouches, spout pouches, and four-side sealed bags.

[0081] One embodiment of the packaging bag of the present invention may be a bag having at least a back seal portion formed by heat-sealing opposing ends of a single film. This back seal portion can be obtained by a method including overlapping sealant layers at opposing ends of a single film and heat-sealing them to form a cylindrical shape. Examples of such packaging bags include three-side sealed bags, gusset bags, and pillow bags.

[0082] The packaging bag of the present invention may also be a bag-in-box, that is, an inner container that combines a soft inner container with an outer container that is generally made of a cardboard box.

[0083] When the packaging container of the present invention is a container with a lid, the oxygen-absorbing sealant film may be the lid material or the container.

[0084] When the oxygen-absorbing sealant film has a paper substrate, the packaging container of the present invention may be a paper laminate pack, such as a beverage pack.

[0085] Other films The other film is not particularly limited and may be, for example, a transparent barrier film. The transparent barrier film may have, for example, the above-mentioned transparent barrier layer, soft resin substrate layer, and sealant layer. Furthermore, a printing layer may be applied to at least a part of the above-mentioned transparent barrier film.

[0086] <Contents> The contents may be, for example, food, medicine, electronic components, etc.

[0087] The food may be, for example, liquid foods such as beverages, edible oils, soups, and liquid seasonings; solid foods such as sweets, cooked rice, and bread; semi-solid foods such as jelly, tofu, miso, mayonnaise, jam, cream, and paste; and powders and granules such as powdered soup.

[0088] The medicinal products may be, for example, medicines, toiletries, cosmetics, and the like.

[0089] The pharmaceutical product may be, for example, a solid pharmaceutical product such as a tablet or capsule, a liquid pharmaceutical product such as an infusion solution, or a semi-solid pharmaceutical product such as a transdermal absorbent.

[0090] The toiletry product may be, for example, shampoo, conditioner, detergent, etc.

[0091] The cosmetic product may be, for example, a milky lotion, a moisturizing lotion, a skin lotion, or the like. [Example]

[0092] The present invention will be specifically explained with reference to examples and comparative examples, but the present invention is not limited to these.

[0093] <<Preparation of oxygen-absorbing sealant film>> Example Using an inflation molding machine, a two-type, three-layer oxygen-absorbing sealant film was obtained by coextrusion inflation molding, having a first skin layer 20 μm thick, an oxygen-absorbing layer 30 μm thick, and a second skin layer 20 μm thick.

[0094] The first and second skin layers are made of linear low-density polyethylene (LLDPE1, density 0.925 g / cm 3 The oxygen absorbing layer was made of a resin composition obtained by mixing 48 parts by mass of a polyethylene-based iron powder-containing masterbatch (iron powder MB, containing 50 to 60% by mass of iron powder), 42 parts by mass of LLDPE, and 10 parts by mass of a polyethylene-based white masterbatch (white MB, containing 55 to 65% by mass of titanium dioxide).

[0095] The Ny film side of a laminate of aluminum-vapor-deposited polyethylene terephthalate (thickness 12 μm) / / nylon (Ny) film (thickness 15 μm) as a barrier substrate layer (" / / " indicates that it is bonded with a dry laminate adhesive) was adhered to the first skin layer side of the obtained oxygen-absorbing sealant film via a two-component dry laminate adhesive to produce the packaging laminate of Example 1.

[0096] Comparative Example and Reference Example 1 Packaging laminates of Comparative Example and Reference Example 1 were produced in the same manner as in Example, except that the type and content of each component was changed as shown in Table 1.

[0097] Other materials shown in Table 1 are as follows: LDPE: Low density polyethylene White PE: Polyethylene resin film containing white pigment

[0098] In Table 1, the term "T die" means that the oxygen-absorbing sealant film was obtained by the co-extrusion T-die method using a T-die molding machine.

[0099] "evaluation" <Heat seal strength> 3(a) and (b), the second skin layer 16 of the same oxygen-absorbing sealant film 10 was placed facing each other at an upper mold temperature of 120°C, a lower mold temperature of 120°C, a sealing time of 0.5 seconds, and a sealing pressure of 0.2 MPa to obtain a laminate 400 for evaluation. The laminate 400 was subjected to a T-peel test in the X direction at a width of 15 mm, a chuck distance of 50 mm, and a pulling speed of 300 mm / min, and the heat seal strength was measured. The peel direction 410A of the sealed portion 410 was 10 mm, and the width 410B perpendicular to the peel direction was 15 mm.

[0100] <Whiteness> In accordance with JIS Z 8781, a spectrophotometer was used to measure L * a * b * L in color space * value, a * value, and b * The whiteness was calculated using these values ​​and the following formula: Whiteness WI=L * +3a * -3b *

[0101] <Oxygen absorption amount> Two 100 mm square packaging laminates were placed in a polyethylene terephthalate / aluminum foil / polyethylene packaging bag with external dimensions of 300 mm x 220 mm, and absorbent cotton soaked in 500 ml of air and 5 ml of water was sealed inside, followed by storage at 40°C. After three days, the oxygen concentration inside the bag containing the packaging laminate was measured, and the difference from the oxygen concentration in the atmosphere was used to calculate the oxygen concentration of 1 cm of the packaging laminate. 2 The amount of oxygen absorbed per bag was calculated. Measurements were performed by inserting the measuring needle of a Pack Reader (RO105L, Iijima Electronics Co., Ltd.), a diaphragm-type galvanic cell oxygen sensor, into the bag.

[0102] Table 1 shows the configurations and evaluation results of the example, comparative example, and reference example 1.

[0103] [Table 1]

[0104] From Table 1, it can be seen that the oxygen-absorbing sealant film of the example, in which the oxygen-absorbing layer contains iron powder, pigment particles, and polyolefin resin, and the sealant layer does not contain pigment particles, can suppress poor appearance caused by the iron powder while maintaining the oxygen absorption rate due to the iron powder.

[0105] Below, the effect of being an inflation film and an embodiment in which the content of iron powder in the oxygen absorbing layer is increased will be described using reference examples.

[0106] <<Preparation of oxygen-absorbing sealant film>> <Reference example 2> Using an inflation molding machine, a two-type, three-layer oxygen-absorbing sealant film was obtained by coextrusion inflation molding, having a first skin layer 20 μm thick, an oxygen-absorbing layer 15 μm thick, and a second skin layer 20 μm thick.

[0107] The first and second skin layers are made of linear low-density polyethylene (LLDPE1, density 0.925 g / cm 3 As the oxygen absorbing layer, a polyethylene master batch containing 50 to 60 mass % of iron powder (iron powder MB) was used.

[0108] A laminate of polyethylene terephthalate (PET) film (thickness 12 μm) / / alloy aluminum (AL) (thickness 9 μm) / / nylon (Ny) film (thickness 15 μm) as a base layer (" / / " indicates that it is bonded with a dry laminate adhesive) was adhered to the first skin layer side of the obtained oxygen-absorbing sealant film via a two-component dry laminate adhesive to produce the packaging laminate of Reference Example 2.

[0109] Reference Examples 3 to 9 and Reference Comparative Examples 1 to 4 Packaging laminates of Reference Examples 3 to 9 and Reference Comparative Examples 1 to 3 were produced in the same manner as Reference Example 2, except that the materials constituting each layer were changed as shown in Table 2. The packaging laminate of Reference Comparative Example 4 was produced by adhering the above-mentioned base layer to the oxygen absorbing layer of a commercially available oxygen-absorbing sealant film having an oxygen absorbing layer and a skin layer in this order.

[0110] Other materials shown in Table 2 are as follows: LLDPE2: Linear low-density polyethylene, density 0.903 g / cm 3 LLDPE3: Linear low-density polyethylene, density 0.922 g / cm 3 LLDPE4: Linear low-density polyethylene, density 0.936 g / cm 3 LDPE: Low-density polyethylene Modified PO: Acid-modified polyolefin

[0111] In Table 2, the term "T die" means that the oxygen-absorbing sealant film was obtained by the co-extrusion T-die method using a T-die molding machine.

[0112] "evaluation" <Heat seal strength> 3(a) and (b), the second skin layer 16 of the same oxygen-absorbing sealant film 10 was placed facing each other at an upper die temperature of 120°C, a lower die temperature of 120°C, a sealing time of 0.5 seconds, and a sealing pressure of 0.2 MPa. The resulting laminate was subjected to a T-peel test in the X direction at a width of 15 mm, a chuck distance of 50 mm, and a pulling speed of 300 mm / min, to measure its heat seal strength. The peel direction 410A of the sealed portion 410 was 10 mm, and the width 410B perpendicular to the peel direction was 15 mm.

[0113] <Oxygen absorption amount> A 6.25cm thick oxygen-absorbing sealant film is placed in a polyethylene terephthalate / aluminum foil / polyethylene bag. 2The bag was then heat-sealed into a tetrahedron so that the volume (air volume) of the bag was 13 mL, and the bag was then stored at 40°C. After 3 days, the oxygen concentration inside the bag containing the oxygen-absorbing sealant film was measured, and the difference with the oxygen concentration in the atmosphere was used to calculate the oxygen concentration of 1 cm of the oxygen-absorbing sealant film. 2 The amount of oxygen absorbed per bag was calculated. Measurements were performed by inserting the measuring needle of a Pack Reader (RO105L, Iijima Electronics Co., Ltd.), a diaphragm-type galvanic cell oxygen sensor, into the bag.

[0114] Table 2 shows the configurations and evaluation results of the reference example and reference comparative example.

[0115] [Table 2]

[0116] From Table 2, it can be seen that the packaging laminate of the reference example, which has a thickness of more than 10 μm, a skin layer made of a polyethylene resin, and an oxygen-absorbing sealant film that is an inflation film, has good heat seal strength without compromising the oxygen absorption rate. [Explanation of symbols]

[0117] 10. Oxygen-absorbing sealant film 12 First Skin Layer 14 Oxygen absorption layer 16 Second Skin 20 Packaging laminate 22 Barrier base layer 24 Adhesive layer 400 Evaluation laminate 410 Seal part 410A Width of the seal in the peeling direction 410B Width of the seal in the direction perpendicular to the peeling direction X Peeling direction

Claims

1. The membrane has at least a first skin layer, an oxygen absorbing layer, and a second skin layer in this order, which are fused together; the oxygen absorbing layer contains iron powder, pigment particles, and a polyolefin resin, and the content of the pigment particles is 5% by mass or more with respect to the mass of the oxygen absorbing layer; and The content of inorganic particles in the second skin layer is 3 mass% or less relative to the mass of the second skin layer. Oxygen-absorbing sealant film.

2. The content of the iron powder in the oxygen absorbing layer is 20 mass% or more with respect to the mass of the oxygen absorbing layer, and the content of the pigment particles in the oxygen absorbing layer is 30% by mass or less with respect to the mass of the oxygen absorbing layer; The oxygen-absorbing sealant film according to claim 1 .

3. 3. The oxygen-absorbing sealant film according to claim 1, wherein the oxygen-absorbing layer has a thickness of 5 μm or more and less than 30 μm.

4. The oxygen-absorbing sealant film according to claim 1 or 2, wherein the content of the iron powder is 40 mass % or more relative to the mass of the oxygen-absorbing layer.

5. 3. The oxygen-absorbing sealant film according to claim 1, wherein the pigment particles are white pigment particles.

6. 3. The oxygen absorbing sealant film according to claim 1, wherein the thickness of the first skin layer is more than 10 μm and less than 50 μm.

7. 3. The oxygen absorbing sealant film according to claim 1, wherein the thickness of the second skin layer is more than 10 μm and less than 50 μm.

8. 3. The oxygen-absorbing sealant film according to claim 1, wherein the first skin layer is made of a polyethylene resin.

9. 9. The oxygen-absorbing sealant film according to claim 8, wherein the polyethylene resin of the first skin layer is a linear low-density polyethylene.

10. The density of the first skin layer is 0.930 g / cm ３ 9. The oxygen-absorbing sealant film according to claim 8, wherein:

11. 3. The oxygen-absorbing sealant film according to claim 1, which is an inflation film.

12. A packaging laminate comprising: The oxygen-absorbing sealant film according to claim 1 or 2, and a substrate layer, The substrate layer is laminated on the surface of the first skin layer of the oxygen-absorbing sealant film opposite to the oxygen-absorbing layer. Packaging laminate.

13. A packaging container comprising the packaging laminate according to claim 12.

14. A packaging container containing a content, the content being contained in the packaging container of claim 13.

Images