JP2019218136A - Carbon dioxide-absorbing sealant film for fermented food, laminate for fermented food and packaging bag for fermented food - Google Patents

Abstract

To provide a carbon dioxide-absorbing sealant film for fermented food that has a high carbon dioxide adsorption ability while having excellent seal strength, and a laminate for fermented food and a packaging bag for fermented food having the same, at low costs.SOLUTION: A carbon dioxide-absorbing sealant film for fermented food 10 has at least a carbon dioxide absorption layer 11 composed of a resin composition containing alkaline earth metal hydroxide, and a heat seal layer 12, and is a multilayer co-extrusion film.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a carbon dioxide-absorbing sealant film for fermented foods, a laminate for fermented foods having the same, and a packaging bag for fermented foods.

In fermented foods represented by miso, for example, in general, ripening of miso is due to the interaction of koji mold, yeast, bacteria, etc. present in the miso, and saccharification, alcohol fermentation, acid fermentation, proteolytic action It is said that a unique color, fragrance, and taste can be produced when such a phenomenon occurs. Of these, alcohol fermentation is a process in which sugars produced by saccharification are subjected to the action of yeast to generate alcohol and carbon dioxide gas, and the process is complicated, but the balance of the reaction is represented by the following formula (I). Become like This reaction is necessary during the brewing process, but if brewing proceeds in a hermetically sealed package, the carbon dioxide gas generated by alcoholic fermentation may cause the packaging bag to burst.
[Chemical I]
C ₆ H ₁₂ O ₆ → 2C ₂ H ₅ OH + 2CO ₂ (I)

  Similar to the above fermented foods, roasted coffee beans and the like can be mentioned as similar examples in which the generation of carbon dioxide gas has an adverse effect on the packaging bag. Roasted coffee beans and the like are generally sold in vacuum packaging, but roasted coffee beans and the like generate a gas containing carbon dioxide as a main component during storage, and the shape of the vacuum package collapses. As a result, the merchandise value of the merchandise body may be reduced or lost even though the quality of the contents does not deteriorate.

  Even if the packaging bag is ruptured in the fermented food, or if the shape of the vacuum package such as roasted coffee beans in the similar example is broken, the contents are preserved as described above. The cause is that carbon dioxide gas is generated inside. In order to remove this carbon dioxide gas, if it is placed in a bag provided with a special gas vent plug for distribution and temporary storage, the cost of the bag becomes high, and the bag is temporarily stored for gas release. There was a problem that the work efficiency was reduced. Therefore, development of a packaging bag capable of efficiently and inexpensively removing carbon dioxide has been awaited.

  Patent Literature 1 discloses a large four-sided sealed bag in which two plastic films are stacked and sealed on three sides to form a bag shape, filled with solid contents, and then sealed at an opening. There is disclosed a large bag for fermented foods, which is provided with a vent hole in a non-seal portion through which contents cannot pass but gas can pass quickly.

  Further, Patent Document 2 discloses that a defibrated yarn formed by bundling ultrafine yarns with a gap of 1 micron formed therein is insert-molded into a central portion of a cylindrical body formed of polyethylene to generate ethylene gas and gas having an integrated structure. A gas release tape provided in a bag or container for contents, which is a check valve that, when inserted into a bag or container, releases gas generated from the inside of the container to the outside and prevents external air from entering. A venting tape which exerts an effect is disclosed.

  Further, Patent Document 3 discloses a carbon dioxide gas absorbing sheet mainly comprising a sheet obtained by molding a mixture of a thermoplastic resin and calcium hydroxide into a sheet.

JP-A-7-96951 JP-A-2002-308341 JP-A-55-59825

  However, the large bag for fermented food described in Patent Literature 1 has a problem that air and moisture enter the inside from the outside, a problem of hygiene, a problem of deterioration of the contents, and a problem of becoming wet. there were. Further, in the gas release tape described in Patent Document 2, it is necessary to prepare the gas release tape separately from the packaging material, and there is a problem that the manufacturing process becomes complicated.

  Furthermore, in the packaging bag using the carbon dioxide gas absorbing sheet of Patent Literature 3, there is a problem that air or moisture enters from the outside of Patent Literature 1, or a gas release tape is prepared separately from the packaging material of Patent Literature 2. However, there is no problem that the manufacturing process is complicated, but there is a problem that the sealing strength is insufficient. If the sealing strength is insufficient or the contents are packed into a package as a packaging bag, the contents will be in direct contact with the resin film containing the carbon dioxide absorbent, and depending on the contents during storage In this case, the carbon dioxide absorbent may elute into the contents, which is a problem not only from the viewpoint of appearance but also from the viewpoint of safety and hygiene.

  Therefore, an object of the present invention is to provide a carbon dioxide-absorbing sealant film for fermented foods having a high carbon dioxide-absorbing ability and an excellent seal strength, a fermented food laminate and a fermented food packaging bag having the same at a low cost. Things. The packaging bag for fermented foods also has a feature that it can prevent the intrusion of air and moisture from the outside even when the content generating carbon dioxide is enclosed, and that no member other than the packaging material is used. Also have.

  The present inventors have conducted intensive studies to solve the above-mentioned problems. As a result, at least, a resin composition containing an alkaline earth metal hydroxide was co-extruded with a resin having a heat sealing property by multilayer co-extrusion to form a carbonate. It has been found that a gas-absorbing multilayer extruded film has a high carbon dioxide gas-absorbing ability, an excellent seal strength, and a low cost. That is, the carbon dioxide-absorbing sealant film for fermented food of the present invention is a carbon dioxide-absorbing sealant film for fermented food having at least a carbon dioxide-absorbing layer and a heat-sealing layer made of a resin composition containing an alkaline earth metal hydroxide. , Characterized in that it is a multilayer co-extruded film.

  In the carbon dioxide-absorbing sealant film for fermented food of the present invention, the alkaline earth metal hydroxide is preferably calcium hydroxide.

  The laminate for fermented food of the present invention is characterized by having a gas barrier layer together with a carbon dioxide-absorbing sealant film layer comprising the carbon dioxide-absorbing sealant film for fermented food of the present invention.

  The packaging bag for fermented food of the present invention is characterized by containing the laminated body for fermented food of the present invention.

  Advantageous Effects of Invention According to the present invention, it is possible to obtain a carbon dioxide-absorbing sealant film for fermented foods having excellent seal strength while having a high carbon dioxide absorption ability, a fermented food laminate having the same, and a fermented food packaging bag having the same at low cost. it can. The packaging bag for fermented foods also has a feature that it can prevent the intrusion of air and moisture from the outside even when the content generating carbon dioxide is enclosed, and that no member other than the packaging material is used. Also have.

BRIEF DESCRIPTION OF THE DRAWINGS It is typical sectional drawing of an example of the carbon dioxide absorption sealant film for fermented foods of this invention. It is a typical sectional view of an example of a layered product for fermented foods of the present invention.

Hereinafter, embodiments of the packaging material of the present invention will be specifically described with reference to the drawings.
(Carbon dioxide absorbing sealant film for fermented food)
FIG. 1 shows a schematic cross-sectional view of an example of the carbon dioxide-absorbing sealant film for fermented food of the present invention. The carbon dioxide-absorbing sealant film 10 for fermented food is a multilayer co-extruded film, and in FIG. 1, at least one carbon dioxide-absorbing layer 11 composed of a resin composition containing an alkaline earth metal hydroxide and two layers The heat sealing layer 12 is provided so that one carbon dioxide gas absorbing layer 11 is sandwiched between the two heat sealing layers 12. The carbon dioxide-absorbing sealant film for fermented food 10 is provided with at least one carbon dioxide-absorbing layer 11 and one heat-sealing layer 12.

  As described above, the carbon dioxide-absorbing sealant film for fermented foods 10 of the present invention is a multilayer co-extruded film, so that it has a high carbon dioxide-absorbing ability and excellent sealing strength, and can be manufactured at low cost. Known methods such as a T-die method and an inflation method can be used for co-extrusion.

Hereinafter, each layer of the carbon dioxide-absorbing sealant film 10 for fermented food will be specifically described.
[Carbon dioxide absorption layer]
The carbon dioxide absorption layer 11 used in the carbon dioxide absorption sealant film 10 for fermented food of the present invention is formed by molding a resin composition obtained by blending an alkaline earth metal hydroxide with a thermoplastic resin into a sheet. Has a high carbon dioxide absorption capacity. Known methods can be used for blending and molding into a sheet, such as blending using a twin-screw extruder or molding into a sheet using a single-screw extruder.

  As the alkaline earth metal hydroxide to be blended with the thermoplastic resin, calcium hydroxide is preferable. Other alkaline earth metal hydroxides, for example, magnesium hydroxide also have a carbon dioxide gas absorbing ability, but calcium hydroxide is preferred from the viewpoint that it is chemically stable and safe to handle and has little effect on the human body.

  Examples of the thermoplastic resin used for the carbon dioxide gas absorbing layer 11 include various polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; polyolefin resins such as polypropylene; polyethylene terephthalate (PET); There are polyacrylonitrile (PAN) and the like, and a resin composed of one or more of them can be used. Of these, polyethylene is preferred from the viewpoint of film forming properties and seal strength, and linear low density polyethylene is particularly preferred.

  The blend ratio of the alkaline earth metal hydroxide in the carbon dioxide gas absorbing layer 11 is preferably from 15 to 70% by mass, and more preferably from 30 to 60% by mass. If this ratio is 15% by mass or more, the carbon dioxide absorption capacity can be sufficiently exhibited. Further, when this ratio is 70% by mass or less, excellent film-forming properties and sheet extrusion characteristics are obtained, and the sheet does not become brittle.

  The thickness of the carbon dioxide gas absorbing layer 11 is not particularly limited, but is preferably 5 to 100 μm, more preferably 10 to 80 μm. When the thickness is 5 μm or more, sufficient film forming properties and carbon dioxide absorption capacity can be obtained, and when the thickness is 100 μm or less, the cost does not become too high.

[Heat seal layer]
The carbon dioxide-absorbing sealant film for fermented foods 10 of the present invention further includes a heat seal layer 12 on one or both surface sides of the carbon dioxide-absorbing layer 11. The heat seal layer 12 is an innermost layer when formed into a packaging bag, and a single packaging material having the heat seal layer 12 (for example, a fermented food laminate 30 described later) is placed inside the heat seal layer 12. After folding and facing each other, or after facing the heat sealing layers 12 of two packaging materials, the heat sealing layers 12 are heated and pressed at the edges to seal them, thereby forming a three-sided bag and a stand. Various packaging bags such as bags can be produced.

  The heat seal layer 12 is a resin layer that can be melted by heat and fused to each other. Examples of the resin used for the heat seal layer 12 include various polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; polyolefin resins such as polyethylene and polypropylene; polyethylene terephthalate (PET); There is acrylonitrile (PAN) and the like, and a resin composed of one or more of them can be used. Of these, polyethylene is preferred from the viewpoint of film forming properties and seal strength, and linear low density polyethylene is particularly preferred.

  The thickness of the heat seal layer 12 is not particularly limited, but is preferably 5 to 50 μm, more preferably 5 to 30 μm. When the thickness is 5 μm or more, sufficient extrusion stability and sealing strength can be obtained, and when the thickness is 50 μm or less, the cost does not become too high.

(Laminated product for fermented food)
FIG. 2 shows a schematic cross-sectional view of an example of the fermented food laminate of the present invention. In FIG. 2, the laminated body 30 for fermented food includes a base layer 21, a printed layer 22, a strength layer 23, and a gas barrier layer 24, together with a carbon dioxide-absorbed sealant film layer 20 composed of the carbon dioxide-absorbed sealant film 10 for fermented food. .

Hereinafter, each layer of the fermented food laminate 30 will be specifically described.
[Base material layer]
As the base material layer 21, a resin film constituting a normal packaging material can be used as appropriate. Specifically, low density polyethylene, medium density polyethylene, high density polyethylene, linear low density polyethylene, polypropylene, polyvinyl alcohol, polyacrylonitrile, polycarbonate, ethylene-vinyl acetate copolymer, ionomer, ethylene- (meth) acrylic acid Copolymer, ethylene-ethyl (meth) acrylate copolymer, ethylene-propylene copolymer, methylpentene, polybutene, acid-modified polyolefin resin, polyamide resin, polystyrene resin, low-crystalline saturated polyester or non-crystalline Crystalline polyester resin, polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polyvinylidene fluoride (PVDF), tetrafluoroethylene-ethylene copolymer (ETFE), polytetrafluoroethylene (PTFE) , It can be used a film made of like MXD6. Among these resin films, polyester resins such as polyethylene terephthalate (hereinafter, also referred to as “PET”), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polybutylene naphthalate (PBN); polycaproamide (Nylon 6), polyamide resins such as polyhexamethylene adipamide (nylon 66) and poly-p-xylylene adipamide (MXD6 nylon); and polyolefin resins such as polyethylene and polypropylene are preferable. In particular, a PET film is more preferable because of its high transparency, excellent dimensional stability, excellent heat resistance, and the like. Further, the polyester resin, the polyamide resin and the polyolefin resin may be a mixture thereof.

  The base layer 21 may be a multilayer film in which two or more resin films are laminated. In the case of a multilayer film, each layer may have the same composition or different compositions. Further, the base material layer 21 preferably has transparency or translucency.

  These resin films may be non-stretched films, but from the viewpoint of transparency and the like, preferably uniaxially stretched films or biaxially stretched films are used. The thickness of the film is not particularly limited, but is preferably 10 to 50 μm, and more preferably 10 to 20 μm. When the thickness is 10 μm or more, sufficient strength is obtained, and when the thickness is 50 μm or less, the film does not become too hard or the cost becomes too high.

  The base layer 21 may have a laminated structure in which a barrier layer is laminated on the resin film layer. By laminating the barrier layer, gas permeation can be prevented, and weight loss of the contents and deterioration of the contents can be effectively suppressed. However, in the fermented food laminate 30 shown in FIG. 2, the gas barrier layer 24 is provided separately from the base layer 21, and the base layer 21 is not provided with a barrier layer.

  The surface of the base material layer 21 may be subjected to a surface treatment for improving wettability, such as a corona treatment, an ozone treatment, and a frame treatment, for improving the adhesiveness. Such a surface treatment is preferably performed on at least the surface of the base material layer 21 on which the print layer 22 is formed. When the base layer 21 has the barrier layer described above, the surface of the barrier layer of the base layer 21 can be subjected to a surface treatment.

[Printing layer]
The printing layer 22 is for enhancing the design of the packaging material and the packaging bag using the packaging material, and is a layer in which predetermined characters, figures, patterns, or patterns such as colors are formed by ink. As the ink, a known ink containing at least one of an organic pigment and an inorganic pigment and a binder resin, and if necessary, various additives can be used. The printing layer 22 can be formed on one surface of the base material layer 21 (including the barrier layer) by a known printing method, for example, gravure printing, offset printing, letterpress printing, screen printing, or the like.

[Strength layer]
The layered product for fermented foods 30 of the present invention may include the strength layer 23 if desired. By providing the fermented food laminate 30 with the strength layer 23, the strength of the packaging bag for fermented food produced using the fermented food laminate 30 from the viewpoint of pinhole resistance can be improved. In addition, independence can be imparted to the packaging bag for fermented food.

  As the strength layer 23, a resin film can be used, and more specifically, a polyester resin such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate, a polyether resin, a polyurethane resin, an epoxy resin, An unstretched or stretched film made of a resin such as a phenolic resin, a polyamide resin, a (meth) acrylic resin, a vinyl resin, and a polyolefin resin can be used.

  The thickness of the strength layer 23 is not particularly limited, but is preferably 10 to 50 μm, and more preferably 10 to 30 μm. When the thickness is 10 μm or more, sufficient strength is obtained, and when the thickness is 50 μm or less, the film does not become too hard or the cost becomes too high.

[Gas barrier layer]
By laminating the gas barrier layer 24, gas permeation can be prevented, and weight loss of the contents and deterioration of the contents can be effectively suppressed.

  The gas barrier layer 24 is made of, for example, an inorganic substance such as an aluminum foil, a vapor-deposited film of an inorganic substance or an inorganic oxide, a vapor-deposited film having the vapor-deposited film on a resin film, or an ethylene-vinyl alcohol copolymer, polyvinylidene chloride, or polyvinyl alcohol. , A layer made of a gas barrier resin such as MXD6, or a combination thereof.

  The thickness of the gas barrier layer 24 is not particularly limited, but is preferably 5 to 30 μm, and more preferably 5 to 20 μm. When the thickness is 5 μm or more, sufficient strength is obtained and pinholes are hardly generated. When the thickness is 30 μm or less, the film does not become too hard or the cost becomes too high.

[Production method of laminated body for fermented food]
The fermented food laminate 30 of the present invention can be manufactured, for example, as follows. A printing layer 22 is formed on one surface of the base layer 21 by printing. Next, the strength layer 23 and the gas barrier layer 24 are dry-laminated on one surface of the print layer 22. Further, a carbon dioxide-absorbing sealant film layer 20 composed of a carbon dioxide-absorbing sealant film for fermented foods 10 having a carbon dioxide-absorbing layer 11 and a heat-sealing layer 12 is overlaid on the gas barrier layer 24, and is laminated by extrusion lamination. The fermented food laminate 30 having the seal layer 12 on the surface can be obtained. A substrate on which a printed layer 22 is formed by printing on one surface of a carbon dioxide-absorbing sealant film layer 20 composed of a carbon dioxide-absorbing sealant film 10 for fermented food having a carbon dioxide-absorbing layer 11 and a heat-sealing layer 12 The layered product 30 for fermented food may be obtained by dry laminating the layer 21, the strength layer 23, and the gas barrier layer 24.

[Production method of packaging bag for fermented food]
The packaging bag for fermented food using the laminated body for fermented food 30 of the present invention can be manufactured, for example, as follows.
For example, the laminated body 30 for fermented food having the heat-seal layer 12 obtained by the above method on the surface, and folded and opposed with the heat-seal layer 12 inside, or two laminated bodies 30 for fermented food, After the heat seal layers 12 are opposed to each other, the heat seal layers 12 are heated and pressed at the edges and sealed to produce various types of fermented food packaging bags such as three-sided bags and stand bags. . The method of heat sealing is not particularly limited, and examples thereof include a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high-frequency seal, and an ultrasonic seal.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[Example 1]
Calcium hydroxide and linear low density polyethylene (SP2020 made by Prime Polymer Co., Ltd .; hereinafter abbreviated as LLDPE) are kneaded using a twin screw extruder (TEX30αx made by Nippon Steel Works, Ltd.) at a temperature of 200 ° C. And a carbon dioxide gas absorbing resin composition containing 30% by mass of calcium hydroxide.
The obtained resin composition and LLDPE (SP2020, manufactured by Prime Polymer Co., Ltd.) are co-extruded in a multilayer at a temperature of 180 ° C., and LLDPE (10 μm) / carbon dioxide-absorbing resin composition (30 μm) / LLDPE (10 μm) Was produced.
A PET (base layer, E5100 manufactured by Toyobo Co., Ltd.), an aluminum foil (gas barrier layer, 1N30 manufactured by Toyo Aluminum Co., Ltd .; hereinafter abbreviated as AL) and an adhesive for dry lamination (manufactured by Rock Paint Co., Ltd.) RU-77T, hereinafter abbreviated as DL), and laminated by dry lamination, PET (12 μm) / DL / AL (7 μm) / DL / LLDPE (10 μm) / carbon dioxide-absorbing resin composition (30 μm) / LLDPE ( 10 μm) was obtained.

[Comparative Example 1]
A laminate of Comparative Example 1 was obtained using the same raw materials, equipment, and manufacturing conditions as in Example 1, except that the carbon dioxide-absorbing resin composition was LLDPE.

[Comparative Example 2] Only a carbon dioxide gas absorbing resin composition (18% by mass of calcium hydroxide) was extruded to produce a 50 µm thick film, and PET (12 µm) / DL / AL (7 µm) was dry-laminated as in Example 1. ) / DL / carbon dioxide absorbing resin composition (50 μm) was obtained.

[Comparative Example 3]
Only the carbon dioxide gas absorbing resin composition is extruded to produce a film having a thickness of 30 μm, which is laminated by PET (12 μm) / DL / AL (7 μm) and sand laminated with LLDPE resin PET (12 μm) / DL / AL (7 μm) / After preparing LLDPE (10 μm) / carbon dioxide-absorbing resin composition (30 μm), PET (12 μm) / DL / AL (7 μm) / LLDPE (10 μm) / carbon dioxide-absorbing resin composition (30 μm) by extrusion lamination of LLDPE. / LLDPE (10 μm) laminate was obtained.

[Evaluation method and results]
(Carbon dioxide absorption capacity test)
From the laminates obtained in Example 1 and Comparative Examples 1 to 3, a pouch having a size of 130 mm × 170 mm was prepared by sealing four sides under the conditions of 180 ° C. and 0.1 MPa with a seal width of 10 mm, and a kimchi (manufactured by Soke Kimchi Co., Ltd.) ) Was sealed without a headspace, and the appearance of the pouch after one week was confirmed. No change was observed in the pouches using the laminates of Example 1 and Comparative Examples 2 and 3, whereas swelling was observed in the pouches using the laminates of Comparative Example 1.

(Seal strength test)
The laminates obtained in Example 1 and Comparative Examples 1 to 3 were cut to a width of 15 mm, and the seal strength was measured using a tensile tester (tensile speed: 300 mm / min). Table 1 shows the results. The seal strength of the laminate of Comparative Example 2 was lower than the seal strength of the laminate of Example 1, Comparative Examples 1 and 3.

  Table 2 shows the results of evaluating carbon dioxide absorption capacity, seal strength, and cost, and comprehensively judging. In Comparative Example 2, the amount of the carbon dioxide gas absorbing resin composition used increases, and in Comparative Example 3, the number of steps increases, so that the cost is higher than in Example 1.

  INDUSTRIAL APPLICABILITY As described above, according to the present invention, a carbon dioxide-absorbing sealant film for fermented foods having a high carbon dioxide-absorbing ability and excellent seal strength, a laminated body for fermented foods having the same, and a fermented food containing them Packaging bags can be obtained at low cost.

DESCRIPTION OF SYMBOLS 10 Carbon dioxide absorption sealant film for fermented foods 11 Carbon dioxide absorption layer 12 Heat seal layer 20 Carbon dioxide absorption sealant film layer 21 Base material layer 22 Printing layer 23 Strength layer 24 Gas barrier layer 30 Layered product for fermented food

Claims (4)

  At least a carbon dioxide-absorbing sealant film for fermented foods having a carbon dioxide-absorbing layer and a heat-sealing layer composed of a resin composition containing an alkaline earth metal hydroxide, which is a multilayer co-extruded film. Carbon dioxide absorption sealant film for fermented foods.   The carbon dioxide-absorbing sealant film for fermented food according to claim 1, wherein the alkaline earth metal hydroxide is calcium hydroxide.   A laminated body for fermented food, comprising a gas barrier layer together with a carbon dioxide-absorbing sealant film layer comprising the carbon dioxide-absorbing sealant film for fermented food according to claim 1 or 2.   A packaging bag for fermented food, comprising the laminated body for fermented food according to claim 3.

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