JP6664283B2 - Oxygen absorbing film roll - Google Patents

Description

The present invention relates to an oxygen-absorbing film roll .

  BACKGROUND ART As a packaging material for foods, drugs, pharmaceuticals, cosmetics, electronic components, and the like, an oxygen-absorbing film is used so that the quality of the contents is not deteriorated by oxidation by oxygen in the package. As this oxygen absorbing film, a film using cerium oxide having oxygen deficiency has been proposed.

  Patent Literature 1 discloses an oxygen absorbing layer which is composed of an oxygen absorbing layer and resin layers provided on both surfaces of the oxygen absorbing layer, wherein the oxygen absorbing layer contains a thermoplastic resin and cerium oxide having oxygen deficiency, and An oxygen-absorbing film is disclosed in which the cerium oxide having the oxygen deficiency is contained in a range of more than 50% by weight and less than 85% by weight.

JP 2012-158125 A

  When a resin composition obtained by kneading cerium oxide having oxygen deficiency is used as an intermediate layer, and an oxygen-absorbing film having a skin layer formed on both surfaces thereof is wound up as a film roll, during winding and up to packaging after winding up During the exposure to air for several hours during which time, oxygen is absorbed from the end of the film roll, which results in the problem that the end of the film is deactivated before packing the film roll. I found it. When the deactivated portion is discarded, the effective width usable for the product is reduced.

  In this regard, cerium oxide having oxygen deficiency has advantages such as not requiring moisture for an oxygen absorption reaction and a high oxygen absorption rate as compared with an iron-based oxygen absorbent, while this high oxygen absorption rate As a result, deactivation due to the absorption of oxygen from the end of the film roll appears remarkably.

  Therefore, there is a need to provide an oxygen-absorbing film that hardly causes such a problem and that can maintain a high oxygen-absorbing ability at the time of production in a wide area.

Means for Solving the Problems The present inventors have conducted intensive studies and found that the above-mentioned problems can be solved by the following means, and completed the present invention. That is, the present invention is as follows:
<1> an oxygen-absorbing film,
A first skin layer, an oxygen absorbing layer, and a second skin layer in this order;
The first skin layer and the second skin layer when the oxygen absorbing layer has cerium oxide having oxygen deficiency and a thermoplastic resin, and when the two oxygen absorbing films are laminated on each other. The static friction coefficient measured in accordance with JIS-K7125 is 0.50 or more, and the thickness A of each of the first skin layer and the second skin layer in μm units, An oxygen-absorbing film in which the ratio A / B of the cerium oxide in the oxygen-absorbing layer to the content B in mass% based on the mass of the entire oxygen-absorbing layer is 0.18 μm / mass% or more; .
<2> The oxygen-absorbing film according to <1>, wherein the thickness of the first skin layer and / or the second skin layer is 20 μm or more.
<3> The oxygen-absorbing film according to <1> or <2>, wherein the first skin layer and the second skin layer have the same thickness.
<4> The oxygen-absorbing film according to any one of <1> to <3>, wherein the first skin layer and the second skin layer are formed of the same thermoplastic resin. .
<5> The oxygen-absorbing film according to any one of <1> to <4>, wherein the ratio A / B is 0.20 μm / mass% or more.
<6> The oxygen-absorbing film according to any one of <1> to <5>, wherein the content B is 57% by mass or less.
<7> The oxygen-absorbing film according to <6>, wherein the content of the cerium oxide is 50% by mass or less based on the mass of the entire oxygen-absorbing layer.
<8> The oxygen-absorbing film according to any one of <1> to <7>, wherein the coefficient of static friction is 0.55 or more.
<9> After exposing the oxygen-absorbing film roll having a width of 320 mm and a length of 200 m obtained by winding the above-described oxygen-absorbing film around a core having a diameter of 92 mm to the atmosphere at room temperature for 1.5 hours. The residual oxygen absorption in a region of 50 mm before and after 20 m from the core side of the oxygen-absorbing film and 25 mm from the position of 20 mm from the side end toward the center of the film in the film width direction is 95% or more. The oxygen-absorbing film according to any one of <1> to <8>.
<10> An oxygen-absorbing film roll, comprising: a core, and the oxygen-absorbing film according to any one of <1> to <9>, wound on the core. .

  According to the present invention, it is possible to provide an oxygen-absorbing film that hardly causes a problem of deactivation of an end portion of a film before packing a film roll, and as a result, can maintain an oxygen absorption amount during manufacturing in a wide area. Can be.

FIG. 1 is a sectional view of the oxygen-absorbing film of the present invention. FIG. 2 is a schematic view of the oxygen-absorbing film roll of the present invention.

《Oxygen absorbing film》
The oxygen-absorbing film of the present invention has a first skin layer, an oxygen-absorbing layer, and a second skin layer in this order. The oxygen absorbing layer contains cerium oxide having oxygen deficiency and a thermoplastic resin. The static friction coefficient between the first skin layer and the second skin layer measured according to JIS-K7125 when two oxygen-absorbing films are laminated on each other is 0.50 or more. Further, the content of cerium oxide in the oxygen absorbing layer in the thickness A of each of the first skin layer and the second skin layer in the unit of μm in units of mass% based on the mass of the entire oxygen absorbing layer. The ratio A / B to the amount B is 0.18 μm /% by mass or more.

  As shown in FIG. 2, the oxygen-absorbing film may be wound around a core (200) to be stored and distributed as an oxygen-absorbing film roll (300). In this case, it can be arranged such that the first skin layer (10a) is located inside and the second skin layer (10b) is located outside. As a result, in the form of the oxygen-absorbing film roll (300), the first skin layer (10a) and the second skin layer (10b) come into contact with each other.

  The present inventors initially thought that since the thermoplastic resin in the oxygen-absorbing layer has oxygen permeability, the deactivation proceeds due to the penetration of oxygen from the end of the oxygen-absorbing layer. However, in the course of the research, the deactivation of the oxygen-absorbing film does not depend on the thickness of the oxygen-absorbing layer, and surprisingly, the static friction coefficient and the above ratio A / B must be within the above range. Due to this, during the winding of the oxygen-absorbing film of the present invention as a film roll and after being exposed to the air after winding, the edge is hardly deactivated, and as a result, high oxygen during production in a wide area It has been found that the absorption capacity can be maintained.

  Without wishing to be bound by theory, this is because the high coefficient of static friction results in good adhesion between the first and second skin layers that are in contact with each other, and as a result the first In addition to making it difficult for oxygen in the air to pass between the skin layer and the second skin layer, the thickness of the skin layer is increased in proportion to the content of cerium oxide having oxygen deficiency in the oxygen absorption layer. This is considered to be due to suppression of promotion of deactivation due to an increase in the content of cerium oxide having oxygen deficiency.

  More specifically, by reducing the content of cerium oxide having oxygen deficiency, the content of the thermoplastic resin increases, and the thermoplastic resin suppresses the rate at which oxygen enters from the end face of the film. Is thought to be able to be alleviated. Further, by increasing the thickness of the skin layer, even when oxygen in the air temporarily enters between the first skin layer and the second skin layer when the oxygen-absorbing film is formed into a film roll, It is considered that the rate at which oxygen invades from the surface of the skin layer is suppressed by the thermoplastic resin, and as a result, it is possible to suppress the oxygen from reaching the oxygen absorbing layer.

  The static friction coefficient measured according to JIS-K7125 between the first skin layer and the second skin layer when two oxygen-absorbing films are laminated on each other is 0.50 or more, 0.55 or more, Or 0.60 or more, and 1.00 or less, 0.80 or less, or 0.70 or less.

  The coefficient of static friction between the first skin layer and the second skin layer is determined by the type of resin (average molecular weight, melt mass flow rate, molecular weight distribution, molecular structure, melting point), thickness, and oxygen absorption layer of each skin layer. Can be adjusted by the content, particle size, and particle shape of cerium oxide, the presence or absence of various additives (such as an antiblocking agent), and the heating conditions during film production.

  Content B of the thickness A of each of the first skin layer and the second skin layer in μm, and the content B of cerium oxide in the oxygen absorbing layer in mass% based on the mass of the entire oxygen absorbing layer. Can be 0.18 μm /% by mass or more, 0.20 μm /% by mass or more, or 0.25% by mass or more, and 1.50 μm /% by mass or less, 1.00 μm /% by mass. % Or less, 0.80 μm /% by weight or less, or 0.60 μm /% by weight or less.

  Here, “each thickness A” refers to the thickness of either one of the first skin layer and the second skin layer. Then, the “ratio A / B of each thickness A to the content B” is the same as above, even when the ratio is calculated using any of the thickness of the first skin layer and the thickness of the second skin layer. Is required to be within the range.

After exposing the oxygen-absorbing film of the present invention to an oxygen-absorbing film roll having a width of 320 mm and a length of 200 m obtained by winding the same on a core having a diameter of 92 mm for 1.5 hours at room temperature in the atmosphere, The residual oxygen absorption in a region of 25 mm ² (25 cm ² ) from the position of 50 mm before and after 20 m from the core side of the oxygen absorbing film and 20 mm from the side edge to the center of the film in the width direction of the film is 95% or more and 97% or more. , Or 100%.

  Here, the residual oxygen absorption rate (%) can be calculated by the formula of saturated oxygen absorption after air exposure / saturated oxygen absorption before air exposure × 100.

  Hereinafter, each component of the oxygen-absorbing film of the present invention will be described.

<Oxygen absorption layer>
The oxygen absorbing layer contains cerium oxide having oxygen deficiency and a thermoplastic resin.

  The content B of the cerium oxide having oxygen deficiency in the oxygen absorbing layer in mass% based on the mass of the entire oxygen absorbing layer is 75% by mass or less based on the mass of the oxygen absorbing layer. Can be. In particular, the content B is preferably 1% by mass or more, 5% by mass or more, 10% by mass or more, or 20% by mass or more from the viewpoint of ensuring good oxygen absorption capacity, and 70% by mass or less. , 65% by mass or less, 57% by mass or less, 50% by mass or less, 45% by mass or less, or 40% by mass or less from the viewpoint of not causing rapid oxygen absorption from the end face of the film.

  The thickness of the oxygen absorbing layer can be 10 μm or more, 20 μm or more, or 30 μm or more, and can be 300 μm or less, 200 μm or less, 100 μm or less, 80 μm or less, or 50 μm or less.

セ Cerium oxide with oxygen deficiency｝
Cerium oxide contained in the oxygen absorbing layer is cerium oxide having oxygen deficiency.

Here, the oxygen deficiency of cerium oxide is reduced by a reduction treatment in a strong reducing atmosphere, as shown in the following formula (1), in which oxygen is forcibly extracted from the crystal lattice of cerium oxide. This is brought about by the state (CeO _2-x , 0 <x <2). The reduction treatment can be performed, for example, by performing a heat treatment at a high temperature such as 1000 ° C. in a reducing atmosphere such as hydrogen gas.
CeO ₂ + xH ₂ → CeO _2-x + xH ₂ O (1)

Then, as shown in the following formula (2), the portion lacking oxygen reacts with oxygen, thereby exhibiting the effect as an oxygen absorbent.
CeO _2-x + (x / 2) O ₂ → CeO ₂ (2)

  The value of x can be a positive number of 1.0 or less, and is preferably a positive number of 0.7 or less. As shown in equation (2) above, cerium oxide does not require the presence of water in the atmosphere in the reaction with oxygen. Therefore, the oxygen-absorbing film of the present invention is particularly effective for contents that dislike moisture.

{Thermoplastic resin}
As the thermoplastic resin, a thermoplastic resin having oxygen permeability can be used. As such a thermoplastic resin, for example, polyolefin resin, polystyrene resin, polyester resin, acrylic resin, polyamide resin, polyurethane resin, polycarbonate resin, polysulfone resin, and derivatives thereof, and mixtures thereof No.

  In the context of the present invention, a polyolefin-based resin means a polymer having an olefin-based monomer such as ethylene or propylene, and therefore not only a polymer (polyolefin) composed of only olefin-based monomers, but also an olefin-based monomer and (meth) It also means polymers composed of other monomers such as acrylic acid, acrylate monomers, vinyl acetate and the like. Further, the polyolefin-based resin may or may not be acid-modified.

  Examples of the polyolefin-based resin include a polyethylene-based resin and a polypropylene-based resin. Examples of the polyethylene resin include low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), ethylene-acrylic acid copolymer (EAA), Methacrylic acid copolymer (EMAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate copolymer (EMA), ethylene-vinyl acetate copolymer (EVA), carboxylic acid-modified polyethylene, ionomer, and These derivatives, as well as mixtures thereof, are mentioned. Examples of the polypropylene-based resin include a polypropylene (PP) homopolymer, a random polypropylene (random PP), a block polypropylene (block PP), a chlorinated polypropylene, a carboxylic acid-modified polypropylene, a derivative thereof, and a mixture thereof. .

  As the thermal characteristics of the thermoplastic resin, for example, when its melt mass flow rate (MFR) is measured according to JIS K7210, it is 0.5 g / 10 min or more, 1.0 g or more, 3.0 g / 10 min or more, Alternatively, it may be not less than 5.0 g / 10 min, and may be not more than 100 g / 10 min, not more than 50 g / 10 min, not more than 30 g / 10 min, not more than 20 g / 10 min, or not more than 15 g / 10 min, or not more than 10 g / 10 min.

<First and second skin layers>
The first and second skin layers are layers laminated on the oxygen absorbing layer. The first and second skin layers can be used to increase the coefficient of static friction between two oxygen-absorbing films when they are laminated together, thereby increasing the adhesion between the films. Furthermore, elimination of cerium oxide in the oxygen absorbing layer can be prevented by the presence of the first and second skin layers.

  The first and second skin layers may be made of a thermoplastic resin. As the thermoplastic resin, the thermoplastic resins described for the oxygen absorbing layer can be used. The thermoplastic resin constituting the first and second skin layers may be the same or different from the thermoplastic resin of the oxygen absorbing layer, or may be the same or different from each other. Good. However, from the viewpoint of improving the affinity between the first and second skin layers to improve the adhesion, and particularly when manufacturing the oxygen-absorbing film by a co-extrusion method such as a multilayer inflation method, the oxygen-absorbing film can be easily formed. From the viewpoint of manufacturing, it is preferable that the first and second skin layers are made of the same type of thermoplastic resin.

  The first thickness A of each of the first and second skin layers is 10 μm or more, 12 μm or more, 15 μm or more, or 20 μm or more, and 40 μm or less, 30 μm or less, or 25 μm or less. The effect of increasing the coefficient of static friction between the skin layer and the second skin layer, the effect of preventing desorption of cerium oxide in the oxygen absorbing layer, the effect of improving lamination properties, and the effect of preventing oxygen from entering from the side of the film are coordinated. Preferred from a viewpoint. In particular, when the oxygen-absorbing film roll is used, even when oxygen in the air enters between the first skin layer and the second skin layer, from the viewpoint of making it difficult for the oxygen to reach the oxygen-absorbing layer. , The thickness A of each of the first and second skin layers is preferably 20 μm or more.

  The thickness A of each of the first and second skin layers may be different as long as the above-mentioned ratio A / B satisfies the above-mentioned range, but in particular, by a co-extrusion method such as a multilayer inflation method. When manufacturing an oxygen-absorbing film, it is preferable that the first and second skin layers have the same thickness from the viewpoint of easily manufacturing the oxygen-absorbing film.

  The thermal properties of the thermoplastic resin constituting the first and second skin layers include, for example, a melt mass flow rate (MFR) of 0.1 g / 10 min or more when measured in accordance with JIS K7210. It may be not less than 0.5 g / 10 min, not less than 1.0 g, not less than 3.0 g / 10 min, or not less than 1.5 g / 10 min, and not more than 30 g / 10 min, not more than 20 g / 10 min, or not more than 15 g / 10 min, 10 g / 10 min. Hereinafter, it may be 8 g / 10 min or less, or 5.0 g / 10 min or less.

《Oxygen absorbing film roll》
As shown in FIG. 2A, the oxygen-absorbing film roll of the present invention comprises a core (200) and the above-described oxygen-absorbing film (100) wound on the core (200). I have it.

  The oxygen-absorbing film roll of the present invention has the above-described oxygen-absorbing film in a state in which the first skin layer and the second skin layer are in good contact with each other, so that the end portion is preserved when stored. It is hard to be deactivated, and as a result, the oxygen absorption amount at the time of production can be maintained in a wide area.

  The width of the oxygen-absorbing film of the oxygen-absorbing film roll of the present invention, that is, the axial length of the core is not particularly limited, for example, 20 mm or more, 50 mm or more, 100 mm or more, 200 mm or more, 300 mm or more, 400 mm Or more, or 500 mm or more, and can be 2000 mm or less, or 1000 mm or less.

  The winding length of the oxygen-absorbing film included in the oxygen-absorbing film roll of the present invention is not particularly limited, and may be, for example, 10 m or more, 30 m or more, 50 m or more, 100 m or more, 200 m or more, 300 m or more, It can be 4000 m or less, 2000 m or less, 1000 m or less, 900 m or less, 800 m or less, 700 m or less, 600 m or less, or 500 m or less.

<Core>
As the core, a core made of paper, metal, or resin can be used, but metal or resin containing no moisture or oxygen molecules is preferable.

  The diameter of the core may be 30 mm or more, 40 mm or more, or 50 mm or more, and may be 300 mm or less, 200 mm or less, or 100 mm or less.

<< Production method of oxygen-absorbing film >>
The oxygen-absorbing film of the present invention includes a step of preparing a resin composition for an oxygen-absorbing layer and a step of forming a film.

  The preparation of the resin composition for an oxygen absorbing layer can be performed by kneading the above-described cerium oxide having oxygen deficiency and a thermoplastic resin. For kneading, for example, a batch kneader such as a kneader or a mixing roll conical mixer, a continuous kneader such as a twin screw kneader, a single screw extruder, a two-roll kneader, a three-roll kneader, or the like is used. In this case, depending on the material to be used, kneading is performed at a temperature of 80 ° C or higher, 100 ° C or higher, 120 ° C or higher, or 140 ° C or higher, and 220 ° C or lower, 200 ° C or lower, or 180 ° C or lower. it can.

  The kneaded resin composition for an oxygen absorbing layer, and the thermoplastic resin constituting the first and second skin layers are formed into an oxygen absorbing layer, and first and second skin layers, respectively. The oxygen-absorbing film of the present invention can be obtained by laminating. For example, the kneaded resin composition can be formed into a film by extrusion molding such as an inflation method, a T-die method, or a casting method. Also, both molding and lamination can be performed by a co-extrusion method such as a multilayer inflation method or a multilayer T-die method.

  The present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to these.

<< Preparation of film roll >>
<Example 1>
30 parts by mass of cerium oxide CeO2 _-x (x = 0.5) having oxygen deficiency and 70 parts by mass of low-density polyethylene were used under a nitrogen atmosphere using a twin-screw extruder (PCM-30, Ikegai Co., Ltd.). The mixture was extruded into pellets to prepare a master batch for an oxygen absorbing layer.

  As the skin layer, linear low-density polyethylene was used.

  The above materials were co-extrusion molded with a two-type three-layer film inflation molding machine (TUL-600R, Placo Co., Ltd.) at a resin temperature of 170 ° C. and a first skin layer of 10 μm / oxygen absorbing layer of 60 μm / The second skin layer is formed into a film having a width of 400 mm and a length of 200 m so as to have a skin layer of 10 μm, and has a winding tension of 45 N / m and a winding taper of 30%. It was wound around a 92 mm winding core to produce the oxygen-absorbing film roll of Example 1.

<Examples 2 to 7 and Comparative Examples 1 to 4>
The content of cerium oxide in the oxygen-absorbing layer and the thickness of each layer as shown in Table 1, and the type of polyethylene used for the skin layer and the production of the film roll so as to have a static friction coefficient as shown in Table 1. Except having adjusted the conditions etc., it carried out similarly to Example 1, and produced the oxygen-absorbing film roll of Examples 2-7 and Comparative Examples 1-4.

《Evaluation》
<Residual oxygen absorption rate>
25 cm ² of the oxygen-absorbing film immediately after film formation is put into a polyethylene terephthalate / aluminum foil / polyethylene packaging bag, and heat-sealed and sealed in a tetrahedral shape so that the volume (air volume) of the packaging bag becomes 15 mL. And stored at room temperature.

One week later, the oxygen concentration in the bag containing the oxygen-absorbing film immediately after film formation was measured, and the oxygen absorption amount per 1 cm ² of the oxygen-absorbing film was calculated from the difference from the oxygen concentration in the atmosphere. The value was defined as the amount of saturated oxygen absorbed before exposure to the atmosphere. The measurement was performed by piercing a measuring needle of Packmaster RO-103 (Iijima Electronic Industry Co., Ltd.) which is a diaphragm type galvanic cell type oxygen sensor into the bag.

Both ends of the formed film roll were cut to a width of 320 mm, and after exposing this film roll to the atmosphere at room temperature for 1.5 hours, the film roll was rewound again, and each of the 50 mm and 50 mm around 20 m from the core side. A film (25 cm ² ) in a region of 25 mm from the position 20 mm from the side edge of the film to the center in the film width direction was sampled, the oxygen absorption amount per 1 cm ^{2 of} the film was calculated in the same manner as above, and the calculated value was exposed to the air. This was taken as the amount of saturated oxygen absorbed later. Next, the residual oxygen absorption rate (%) was calculated by the formula of saturated oxygen absorption after air exposure / saturated oxygen absorption before air exposure × 100.

<Static friction coefficient>
About each produced film, the static friction coefficient between the first skin layer and the second skin layer was measured in accordance with JIS-K7125. The measurement was performed using a friction measuring machine (TR-2, Toyo Seiki Seisaku-sho, Ltd.) under the conditions of a measuring speed of 100 mm / min, a measuring distance of 10 mm, a sliding piece of 200 g (lower felt surface), and a contact area of 40 cm ² . .

  The measurement is performed after the sample surface is thoroughly rinsed with a solvent such as acetone to eliminate the influence of the adhesive on the film surface and the lubricant contained in the resin, and left in a measurement environment (23 ° C., 50% RH) environment for 16 hours or more. Was.

  Table 1 shows the results.

  From Table 1, the oxygen-absorbing film rolls of Examples 1 to 7 in which the static friction coefficient is 0.50 or more and the ratio A / B is 0.18 μm / mass% or more are the same as those of Comparative Examples 1 to 4. It can be understood that the residual oxygen absorption rate is better than that of the oxygen-absorbing film roll.

10a first skin layer 10b second skin layer 20 oxygen absorbing layer 22 cerium oxide having oxygen deficiency 24 thermoplastic resin 100 oxygen absorbing film 200 core 300 oxygen absorbing film roll

Claims (9)

Core, and wound on the core, comprising an oxygen-absorbing film, an oxygen-absorbing film roll,
The oxygen-absorbing film,
A first skin layer, an oxygen absorbing layer, and a second skin layer in this order;
The first skin layer and the second skin layer when the oxygen absorbing layer has cerium oxide having oxygen deficiency and a thermoplastic resin, and when the two oxygen absorbing films are stacked on each other. Between the static friction coefficient measured in accordance with JIS-K7125 is 0.50 or more ,
The thickness A of each of the first skin layer and the second skin layer in units of μm, and the cerium oxide in the oxygen absorbing layer in mass% units based on the mass of the entire oxygen absorbing layer. the ratio a / B to the content B is state, and are more 0.18 .mu.m / wt%, and
The thickness of the oxygen absorbing layer is 10 to 100 μm,
Oxygen absorbing film roll . The oxygen-absorbing film roll according to claim 1, wherein the thickness of the first skin layer and / or the second skin layer is 20 µm or more. The oxygen-absorbing film roll according to claim 1, wherein the thickness of the first skin layer and the thickness of the second skin layer are equal. The oxygen-absorbing film roll according to any one of claims 1 to 3, wherein the first skin layer and the second skin layer are formed of the same thermoplastic resin. The oxygen-absorbing film roll according to claim 1, wherein the ratio A / B is 0.20 μm /% by mass or more. The oxygen-absorbing film roll according to any one of claims 1 to 5, wherein the content B is 57% by mass or less. The oxygen-absorbing film roll according to claim 6, wherein the content B is 50% by mass or less. The oxygen-absorbing film roll according to any one of claims 1 to 7, wherein the coefficient of static friction is 0.55 or more. After exposing a roll of oxygen-absorbing film having a width of 320 mm and a length of 200 m obtained by winding the oxygen-absorbing film around a core having a diameter of 92 mm to the atmosphere at room temperature for 1.5 hours, The residual oxygen absorption rate in a region of 50 mm before and after 20 m from the core side of the conductive film and 25 mm from the position of 20 mm from the side end toward the center in the width direction is 95% or more. The oxygen-absorbing film roll according to claim 1 .

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