JP2020175902A - Multilayered film for packaging meat and package - Google Patents

Abstract

To provide a package capable of suppressing drip occurrence during storage of packaged meat, and a film for manufacturing the package.SOLUTION: A multilayered film 1 for packaging meat has a sealant layer 11 and a protective layer 14. The protective layer 14 includes nylon, and the sealant layer 11 includes an ionomer. A package has the multilayered film 1 for packaging meat.SELECTED DRAWING: Figure 1

Description

The present invention relates to a multilayer film for meat packaging and a package.

As a packaging bag for meat, a bag using a multilayer film having an oxygen barrier property and a sealing property is conventionally known. Such a packaging bag is configured to include, for example, a bottom material and a lid material, and the bottom material is formed with a recess for forming a storage portion for storing meat. Then, either one or both of the bottom material and the lid material use the multilayer film.

When packaging the meat, the meat is stored in the recess of the bottom material, and the surface of the bottom material on which the meat is exposed and the surface of the lid material are overlapped with each other, and the inside of the recess is evacuated. Then, by heat-sealing the peripheral portions of the bottom material and the lid material, a storage portion is formed and the meat is sealed in the storage portion. Since either or both of the bottom material and the lid material are transparent, the stored meat can be easily seen from the outside of the package (see Patent Documents 1 and 2).

In the packaging bag in which the meat is stored in this way, the bottom material and the lid material are sealed at the peripheral portion, whereas the region is closer to the storage portion than the sealed portion and is not included in the storage portion. Is usually kept in close contact between the bottom material and the lid material by the effect of depressurization by evacuation in the storage portion in an unsealed or lightly sealed state. In the present specification, the region of the package in which the bottom material and the lid material are in close contact with each other is referred to as a “non-sealed portion” in the sense that it is not completely sealed.

JP-A-2008-127035 Japanese Unexamined Patent Publication No. 2005-1191982

Liquids may leak from the meat being stored. In the present specification, the liquid leaked from the meat in this way is referred to as "drip". And, unless special measures are taken, drip may occur even from the meat stored in the package. Further, in that case, drip may accumulate in the above-mentioned non-sealing portion of the package. When the drip occurs in this way, there is a problem in appearance that the packaged state of the meat becomes unattractive.

An object of the present invention is to provide a package capable of suppressing the occurrence of drip during packaging and storage of meat, and a film for producing the package.

In order to solve the above problems, the present invention adopts the following configuration.
[1]. A multilayer film for meat packaging, comprising a sealant layer and a protective layer, wherein the protective layer contains nylon and the sealant layer contains an ionomer.
[2]. The multilayer film for meat packaging according to [1], wherein the metal ions constituting the ionomer are zinc ions or sodium ions.
[3]. The multilayer film for meat packaging according to [1] or [2], wherein the ionomer is an ethylene-based copolymer ionomer.
[4]. A package body comprising the multilayer film for meat packaging according to any one of [1] to [3].
[5]. The packaging body includes a lid material and a bottom material, the packaging body is composed of a seal of the lid material and the bottom material, and either one or both of the lid material and the bottom material is for the meat packaging. The packaging body according to [4], which comprises a multilayer film.

According to the present invention, a package capable of suppressing the occurrence of drip during packaging and storage of meat and a film for producing the package are provided.

It is sectional drawing which shows typically an example of the multilayer film which concerns on one Embodiment of this invention. It is sectional drawing which shows typically the package which concerns on one Embodiment of this invention.

<< Multilayer film for meat packaging >>
The multilayer film for meat packaging according to an embodiment of the present invention includes a sealant layer and a protective layer, the protective layer containing nylon, and the sealant layer containing an ionomer.
Since the multilayer film for meat packaging of the present embodiment includes a sealant layer containing an ionomer, it is possible to suppress the generation of drip from the stored meat in the package composed of the multilayer film. In addition, the package has a high so-called self-weld property in which the adhesion of the non-sealed portion is stably maintained. Here, as described above, the "non-sealed portion" means an area of the package that is closer to the storage portion than the sealed portion and is not included in the storage portion, and is usually not sealed or is not included. This is a region where the bottom material and the lid material are in close contact with each other due to the effect of decompression by vacuuming in the storage portion in a lightly sealed state.
On the other hand, the multilayer film for meat packaging of the present embodiment has high so-called pinhole resistance, which suppresses the generation of pinholes penetrating the multilayer film in the thickness direction by providing a protective layer containing nylon. .. Therefore, the package made of this multilayer film has a high meat packaging effect.

In the present specification, the "multilayer film for meat packaging" of the present embodiment may be simply referred to as "multilayer film". In the present specification, the description of "multilayer film" means "multilayer film for meat packaging" of the present embodiment unless otherwise specified.

The multilayer film of the present embodiment is suitable as either a lid material or a bottom material for forming a packaging body described later.

Hereinafter, the present invention will be described in detail with reference to the drawings. In addition, in the figure used in the following description, in order to make it easy to understand the features of the present invention, the main part may be enlarged for convenience, and the dimensional ratio of each component is the same as the actual one. Is not always the case.

FIG. 1 is a cross-sectional view schematically showing an example of the multilayer film of the present embodiment.
The multilayer film 1 shown here includes a sealant layer 11 and a protective layer 14.
Further, the multilayer film 1 is provided with an intermediate layer 12 and a first adhesive layer 131 in this order between the sealant layer 11 and the protective layer 14 in the direction from the sealant layer 11 to the protective layer 14, and is a protective layer. An oxygen barrier layer 15, a second adhesive layer 132, and an outer layer 16 are provided on the 14 in this order in a direction away from the sealant layer 11. That is, the multilayer film 1 includes a sealant layer 11, and on the sealant layer 11, an intermediate layer 12, a first adhesive layer 131, a protective layer 14, an oxygen barrier layer 15, a second adhesive layer 132, and an outer layer are provided. 16 and 16 are laminated in this order in these thickness directions.
In the present specification, a plurality of adhesive layers such as the first adhesive layer 131 and the second adhesive layer 132 may be collectively referred to as "adhesive layer".

<Sealant layer>
The sealant layer 11 contains ionomers.
The sealant layer 11 is one outermost layer of the multilayer film 1, and is an exposed surface of the sealant layer 11 on the side opposite to the intermediate layer 12 side (in this specification, it may be referred to as a "first surface"). Reference numeral 11a is one outermost surface of the multilayer film 1.
The first surface 11a of the sealant layer 11 is a sealing surface, a part of which is overlapped with the surface of another film and sealed by heating, and as a result, a package is formed. On the other hand, a part of the unsealed area constitutes a storage portion for the target meat in the package and comes into contact with the meat.

By packaging the meat in the packaging bag obtained by using the multilayer film 1, the surface of the meat in the storage portion comes into contact with the first surface 11a of the sealant layer 11. Therefore, the meat packaged in the packaging bag is stored with its surface in contact with the sealant layer 11 containing ionomer. In the meat preserved in this way, the occurrence of drip is suppressed.
Further, in the unsealed portion of the packaging bag after packaging the meat, the first surface 11a of the sealant layer 11 is in close contact with the surface of another film or the surface of the sealant layer similar to the sealant layer 11. The state is maintained. As described above, since one or both of the contact surfaces are the sealant layer (sealant layer 11) in the present embodiment, the adhesion of the non-sealed portion is stably maintained. By maintaining the adhesiveness in this way, even if a small amount of drip is generated, the drip does not accumulate in the non-sealed portion, and the appearance of the packaged state of the meat is maintained in good condition.

The sealant layer 11 may contain only ionomers (that is, may consist of ionomers), and may be referred to as ionomers and other components (referred to as "other components" in the present specification). (There is) (ie, it may consist of an ionomer and the other components mentioned above).

The ionomer is composed of a base resin and a metal ion, and more specifically, has a bridging structure in which an acid moiety (for example, a carboxy group) in the base resin and a metal ion form a salt. There is.

Examples of the base resin include a copolymer having a structural unit derived from an olefin and a structural unit derived from an α, β-unsaturated carboxylic acid.
Examples of the olefin include ethylene, propylene, 1-butene, styrene and the like.
Examples of the α, β-unsaturated carboxylic acid include (meth) acrylic acid and maleic acid.
In addition, in this specification, "(meth) acrylic acid" is a concept including both "acrylic acid" and "methacrylic acid". The same applies to terms similar to (meth) acrylic acid.

The base resin constituting the ionomer has a structural unit derived from an olefin, a structural unit derived from α, β-unsaturated carboxylic acid, and other structural units that do not correspond to any of these. May be good.

Examples of the other structural unit include a structural unit derived from α, β-unsaturated carboxylic acid ester, a structural unit derived from vinyl acetate, and the like.
Examples of the α, β-unsaturated carboxylic acid ester include (meth) acrylic acid ester and maleic acid ester.
Examples of the alcohol constituting the α, β-unsaturated carboxylic acid ester and maleic acid ester include linear or branched alcohols having 1 to 10 carbon atoms, and more specifically, methanol. Ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol (sec-butyl alcohol), 2-methyl-1-propanol (isobutyl alcohol), 2-methyl-2-propanol (tert-butyl alcohol), 1-pentanol, 2-pentanol, 3-methyl-1-butanol (isoamyl alcohol), 2-methyl-2-butanol (tert-amyl alcohol), 2,2-dimethyl-1-propanol (neopentyl alcohol) , 1-hexanol, 1-octanol, 2-ethylhexanol, 1-decanol and the like.

The structural unit derived from the olefin of the base resin, the structural unit derived from α, β-unsaturated carboxylic acid, and the other structural units may be only one kind, or 2 There may be more than one species, and when there are two or more species, their combinations and ratios can be arbitrarily selected.

As the preferred base resin, for example, a copolymer having a structural unit derived from ethylene and a structural unit derived from a monomer other than ethylene (in the present specification, "ethylene-based copolymer"). (Sometimes referred to as); a copolymer having a structural unit derived from styrene and a structural unit derived from a monomer other than styrene (in the present specification, it may be referred to as a "styrene-based copolymer". There is).

As the preferred ethylene-based copolymer, for example, a copolymer having a structural unit derived from ethylene and a structural unit derived from (meth) acrylic acid (in the present specification, "ethylene- (in this specification)". Meta) may be referred to as "acrylic acid copolymer resin").
As the preferred styrene-based copolymer, for example, a copolymer having a structural unit derived from styrene and a structural unit derived from (meth) acrylic acid (in the present specification, "styrene- (in the present specification)". (Meta) may be referred to as "acrylic acid copolymer resin").

The preferred ethylene- (meth) acrylic acid copolymer resin is, for example, an ethylene- (meth) acrylic acid copolymer having no other structural unit; as the other structural unit, a (meth) acrylic acid ester. Ethylene- (meth) acrylic acid- (meth) acrylic acid ester copolymer having, as the other structural unit, an ethylene- (meth) acrylic acid-maleic acid ester copolymer having maleic acid ester, etc. Can be mentioned.
The preferred styrene- (meth) acrylic acid copolymer resin is, for example, a styrene- (meth) acrylic acid copolymer having no other structural unit; as the other structural unit, a (meth) acrylic acid ester. Styrene- (meth) acrylic acid- (meth) acrylic acid ester copolymer having styrene- (meth) acrylic acid- (meth) acrylic acid ester copolymer; as the other structural unit, styrene- (meth) acrylic acid-maleic acid ester copolymer having maleic acid ester and the like Can be mentioned.

The base resin is preferably the ethylene-based copolymer. That is, the ionomer is preferably an ethylene-based copolymer ionomer.

Examples of the metal ion constituting the ionomer include monovalent ions such as sodium ion (Na ⁺ ), potassium ion (K ⁺ ), silver ion (Ag ⁺ ), and copper (I) ion (Cu ⁺ ); barium ion. Examples thereof include divalent ions (polyvalent ions) such as (Ba ²⁺ ), zinc ions (Zn ²⁺ ), copper (II) ions (Cu ²⁺ ), and iron (II) ions (Fe ²⁺ ).

Among these, the metal ion constituting the ionomer is preferably zinc ion or sodium ion, and more preferably zinc ion.

The metal ions contained in the ionomer may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

More preferable ionomers include, for example, an ionomer containing an ethylene- (meth) acrylic acid copolymer and a sodium ion; an ionomer containing an ethylene- (meth) acrylic acid copolymer and a zinc ion; an ethylene- (meth). Ionomer containing acrylic acid- (meth) acrylic acid ester copolymer and sodium ion; Ionomer containing ethylene- (meth) acrylic acid- (meth) acrylic acid ester copolymer and zinc ion; ethylene- (meth) Ionomer containing acrylic acid-maleic acid ester copolymer and sodium ion; ionomer containing ethylene- (meth) acrylic acid-maleic acid ester copolymer and zinc ion; styrene- (meth) acrylic acid copolymer and Ionomer containing sodium ion; Ionomer containing styrene- (meth) acrylic acid copolymer and zinc ion; Ionomer containing styrene- (meth) acrylic acid- (meth) acrylic acid ester copolymer and sodium ion; Ionomer containing styrene- (meth) acrylic acid- (meth) acrylic acid ester copolymer and zinc ion; ionomer containing styrene- (meth) acrylic acid-maleic acid ester copolymer and sodium ion; styrene-( Meta) Examples thereof include ionomers containing an acrylic acid-maleic acid ester copolymer and zinc ions.

The ionomer is more preferably an ethylene-based copolymer ionomer in which the metal ion is a zinc ion or a sodium ion, and the ionomer is an ethylene-based copolymer ionomer in which the metal ion is a zinc ion. Is particularly preferable.

The ionomer contained in the sealant layer 11 may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

The other component contained in the sealant layer 11 is not particularly limited and may be arbitrarily selected depending on the intended purpose. For example, it may be either a resin component or a non-resin component.

The other component, which is a resin component, is a resin other than the ionomer.
Examples of the other component, which is a non-resin component, include additives known in the art.
Examples of the additive include antioxidants, antistatic agents, crystal nucleating agents, inorganic particles, thickeners, thickeners, heat stabilizers, lubricants, infrared absorbers, ultraviolet absorbers, antifogging agents and the like. Can be mentioned.

The other components contained in the sealant layer 11 may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

The ratio of the ionomer content to the total mass of the sealant layer 11 in the sealant layer 11 is preferably 85% by mass or more, more preferably 90% by mass or more, and preferably 95% by mass or more. More preferably, it may be, for example, 97% by mass or more and 99% by mass or more. When the ratio is equal to or higher than the lower limit value, in a package constructed by using the multilayer film 1, the effect of suppressing the generation of drip from the stored meat without impairing the sealing strength of the sealant layer 11 is obtained. , The effect of maintaining stable adhesion of the non-sealed portion, and both become higher.
The upper limit of the ratio is not particularly limited. For example, the ratio may be 100% by mass or less.

In other words, the ratio of the content of the other components to the total mass of the sealant layer 11 in the sealant layer 11 is preferably 15% by mass or less, more preferably 10% by mass or less, and 5% by mass. % Or less is more preferable, and for example, it may be any of 3% by mass or less and 1% by mass or less. When the ratio is not more than the upper limit value, the above-mentioned effect becomes higher.
The lower limit of the ratio is not particularly limited. For example, the ratio may be 0% by mass or more.

The sealant layer 11 may be composed of one layer (single layer) or may be composed of two or more layers. When the sealant layer 11 is composed of a plurality of layers, the plurality of layers may be the same or different from each other, and the combination of the plurality of layers is not particularly limited as long as the effects of the present invention are not impaired.

In the present specification, not only in the case of the sealant layer 11, "a plurality of layers may be the same or different from each other" means "all layers may be the same or all layers may be the same". It means that "they may be different, or only some of the layers may be the same", and "multiple layers are different from each other" means that "at least one of the constituent materials and the thickness of each layer is different from each other". It means that.

The thickness of the sealant layer 11 is preferably 3 to 100 μm, more preferably 5 to 70 μm, regardless of whether the multilayer film 1 is for the lid material or the bottom material of the packaging body described later. It is more preferably 7 to 50 μm, and may be, for example, 10 to 40 μm. When the thickness of the sealant layer 11 is at least the above lower limit value, the sealing strength of the sealant layer 11 becomes higher. When the thickness of the sealant layer 11 is not more than the upper limit value, it is possible to prevent the sealant layer 11 from becoming excessively thick.
Here, the "thickness of the sealant layer 11" means the thickness of the entire sealant layer 11, and for example, the thickness of the sealant layer 11 composed of a plurality of layers is the total of all the layers constituting the sealant layer 11. Means the thickness of.

<Protective layer>
The protective layer 14 contains nylon.
The protective layer 14 imparts strong piercing strength, pinhole resistance, and the like to the multilayer film 1.

The protective layer 14 may contain only nylon (that is, may be made of nylon), and may be referred to as nylon and other components (in the present specification, "other components"). (Ie, it may consist of nylon and the other components mentioned above).

Examples of the nylon include 4-nylon, 6-nylon, 7-nylon, 11-nylon, 12-nylon, 46-nylon, 66-nylon, 69-nylon, 610-nylon, 611-nylon, 612-nylon. , 6T-nylon, 6I nylon, copolymer of 6-nylon and 66-nylon (nylon 6/66), copolymer of 6-nylon and 610-nylon, copolymer of 6-nylon and 611-nylon, 6-nylon And 12-nylon copolymer (nylon 6/12), 6-nylon and 612 nylon copolymer, 6-nylon and 6T-nylon copolymer, 6-nylon and 6I-nylon copolymer, 6-nylon and 610-nylon copolymer with 66-nylon, 12-nylon copolymer with 6-nylon and 66-nylon (nylon 6/66/12), copolymer of 6-nylon, 66-nylon and 612-nylon, 66 Examples include a copolymer of -nylon and 6T-nylon, a copolymer of 66-nylon and 6I-nylon, a copolymer of 6T-nylon and 6I-nylon, a copolymer of 66-nylon, 6T-nylon and 6I-nylon, and the like. ..
Among these, preferred nylons include 6-nylon and nylon 6/66.

The nylon contained in the protective layer 14 may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

The other component contained in the protective layer 14 is not particularly limited and may be arbitrarily selected depending on the intended purpose. For example, it may be either a resin component or a non-resin component.

The other component, which is a resin component, is a resin other than nylon.
Examples of the other component, which is a non-resin component, include additives known in the art.
Examples of the additive include the same additives that the sealant layer 11 may contain.

The other component contained in the protective layer 14 may be only one kind, may be two or more kinds, and when there are two or more kinds, the combination and ratio thereof can be arbitrarily selected.

The ratio of the nylon content to the total mass of the protective layer 14 in the protective layer 14 is preferably 85% by mass or more, more preferably 90% by mass or more, and preferably 95% by mass or more. More preferably, it may be, for example, 97% by mass or more and 99% by mass or more. When the ratio is at least the lower limit value, the pinhole resistance becomes higher in the package constructed by using the multilayer film 1.
The upper limit of the ratio is not particularly limited. For example, the ratio may be 100% by mass or less.

In other words, the ratio of the content of the other components to the total mass of the protective layer 14 in the protective layer 14 is preferably 15% by mass or less, more preferably 10% by mass or less, and 5% by mass. It is more preferably% or less, and may be, for example, any of 3% by mass or less and 1% by mass or less. When the ratio is not more than the upper limit value, the above-mentioned effect becomes higher.
The lower limit of the ratio is not particularly limited. For example, the ratio may be 0% by mass or more.

The protective layer 14 may be composed of one layer (single layer), or may be composed of two or more layers. When the protective layer 14 is composed of a plurality of layers, the plurality of layers may be the same as or different from each other, and the combination of the plurality of layers is not particularly limited as long as the effects of the present invention are not impaired.

The thickness of the protective layer 14 is preferably 3 to 100 μm, more preferably 5 to 70 μm, regardless of whether the multilayer film 1 is used for the lid material or the bottom material of the packaging body described later. It is more preferably 7 to 50 μm, and may be, for example, 10 to 40 μm. When the thickness of the protective layer 14 is at least the above lower limit value, the pinhole resistance of the multilayer film 1 becomes higher. When the thickness of the protective layer 14 is not more than the upper limit value, it is possible to prevent the protective layer 14 from becoming excessively thick.
Here, the "thickness of the protective layer 14" means the thickness of the entire protective layer 14, for example, the thickness of the protective layer 14 composed of a plurality of layers is the total of all the layers constituting the protective layer 14. Means the thickness of.

<Middle layer>
The intermediate layer 12 imparts a function to the multilayer film 1 separately from the sealant layer 11 and the protective layer 14.
In the multilayer film of the present embodiment, the intermediate layer has an arbitrary configuration, and the multilayer film may or may not have an intermediate layer, but in that the multilayer film has higher functionality, it may or may not be provided. It is preferable to have it.

Examples of the intermediate layer 12 include a layer that improves the strength or handleability of the multilayer film 1 by increasing the thickness of the entire multilayer film 1 to a certain value or more.
Examples of the layer for increasing the thickness include ethylene- (meth) acrylic acid copolymer (EMAA), ethylene-based ionomer, low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high density polyethylene. Examples include a layer containing a resin such as high density polyethylene (HDPE) and ethylene-vinyl acetate copolymer (EVA).

The above-mentioned intermediate layer 12 (layer for increasing the thickness) may contain only the resin (that is, may be composed of the resin), and the resin and other components (the present). In the specification, it may contain (sometimes referred to as "another component") (that is, it may consist of the resin and the other component).

The resin contained in the intermediate layer 12 may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected according to the purpose. ..

The other components contained in the intermediate layer 12 are not particularly limited and can be arbitrarily selected depending on the intended purpose.
Examples of the other component include additives known in the art that are non-resin components, and examples of the additive include the same additives that the sealant layer 11 may contain. ..

The other components contained in the intermediate layer 12 may be only one kind, may be two or more kinds, and when there are two or more kinds, the combination and ratio thereof can be arbitrarily selected.

The ratio of the content of the resin to the total mass of the intermediate layer 12 in the intermediate layer 12 is preferably 85% by mass or more, more preferably 90% by mass or more, and 95% by mass or more. Is more preferable, and for example, it may be any of 97% by mass or more and 99% by mass or more. When the ratio is at least the lower limit value, the effect of providing the intermediate layer 12 in the multilayer film 1 becomes higher.
The upper limit of the ratio is not particularly limited. For example, the ratio may be 100% by mass or less.

In other words, the ratio of the content of the other components to the total mass of the intermediate layer 12 in the intermediate layer 12 is preferably 15% by mass or less, more preferably 10% by mass or less, and 5% by mass. It is more preferably% or less, and may be, for example, any of 3% by mass or less and 1% by mass or less. When the ratio is not more than the upper limit value, the above-mentioned effect becomes higher.
The lower limit of the ratio is not particularly limited. For example, the ratio may be 0% by mass or more.

The intermediate layer 12 may be composed of one layer (single layer) or may be composed of a plurality of layers of two or more layers. When the intermediate layer 12 is composed of a plurality of layers, the plurality of layers may be the same as or different from each other, and the combination of the plurality of layers is not particularly limited as long as the effects of the present invention are not impaired.

The thickness of the intermediate layer 12 is preferably 5 to 120 μm, more preferably 10 to 100 μm, regardless of whether the multilayer film 1 is for the lid material or the bottom material of the packaging body described later. It is preferably 15 to 80 μm, more preferably 15 to 65 μm, for example. When the thickness of the intermediate layer 12 is at least the lower limit value, the effect obtained by providing the intermediate layer 12 becomes higher. When the thickness of the intermediate layer 12 is not more than the upper limit value, it is possible to prevent the intermediate layer 12 from becoming excessively thick.
Here, the "thickness of the intermediate layer 12" means the thickness of the entire intermediate layer 12, and for example, the thickness of the intermediate layer 12 composed of a plurality of layers is the total of all the layers constituting the intermediate layer 12. Means the thickness of.

<Oxygen barrier layer>
The oxygen barrier layer 15 imparts a strong oxygen barrier property (in other words, a property of suppressing the permeation of oxygen gas) to the multilayer film 1.
In the multilayer film of the present embodiment, the oxygen barrier layer has an arbitrary configuration, and the multilayer film may or may not have an oxygen barrier layer, but the oxygen barrier property is remarkably improved. Is preferably provided.

Examples of the resin component contained in the oxygen barrier layer 15 include oxygen-barrier resins such as ethylene-vinyl acetate copolymer saponified products (in this specification, they may be abbreviated as “EVOH”).

The oxygen barrier layer 15 may contain only the oxygen barrier resin (that is, it may be made of the oxygen barrier resin), the oxygen barrier resin and other components (in the present specification). May contain (sometimes referred to as "other components") (ie, may consist of an oxygen barrier resin and the other components).

The oxygen barrier resin contained in the oxygen barrier layer 15 may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof are arbitrary depending on the purpose. Can be selected.

The other component contained in the oxygen barrier layer 15 is not particularly limited and may be arbitrarily selected depending on the intended purpose. For example, it may be either a resin component or a non-resin component.

The other component, which is a resin component, is a resin other than the oxygen barrier resin.
Examples of the other component, which is a non-resin component, include additives known in the art.
Examples of the additive include the same additives that the sealant layer 11 may contain.

The other components contained in the oxygen barrier layer 15 may be only one kind, may be two or more kinds, and when there are two or more kinds, the combination and ratio thereof can be arbitrarily selected.

The ratio of the content of the oxygen barrier resin to the total mass of the oxygen barrier layer 15 in the oxygen barrier layer 15 is preferably 85% by mass or more, more preferably 90% by mass or more, and 95% by mass. The above is more preferable, and for example, it may be any of 97% by mass or more and 99% by mass or more. When the ratio is at least the lower limit value, the oxygen barrier property becomes higher in the package constructed by using the multilayer film 1.
The upper limit of the ratio is not particularly limited. For example, the ratio may be 100% by mass or less.

In other words, the ratio of the content of the other components to the total mass of the oxygen barrier layer 15 in the oxygen barrier layer 15 is preferably 15% by mass or less, more preferably 10% by mass or less. It is more preferably 5% by mass or less, and may be, for example, 3% by mass or less and 1% by mass or less. When the ratio is not more than the upper limit value, the above-mentioned effect becomes higher.
The lower limit of the ratio is not particularly limited. For example, the ratio may be 0% by mass or more.

The oxygen barrier layer 15 may be composed of one layer (single layer) or may be composed of two or more layers. When the oxygen barrier layer 15 is composed of a plurality of layers, the plurality of layers may be the same or different from each other, and the combination of the plurality of layers is not particularly limited as long as the effects of the present invention are not impaired.

The thickness of the oxygen barrier layer 15 is preferably 2 to 20 μm, preferably 3 to 16 μm, regardless of whether the multilayer film 1 is used for the lid material or the bottom material of the packaging body described later. It is more preferably 3 to 12 μm, and may be, for example, 3 to 10 μm. When the thickness of the oxygen barrier layer 15 is at least the above lower limit value, the oxygen barrier property of the multilayer film 1 becomes higher. When the thickness of the oxygen barrier layer 15 is not more than the upper limit value, it is possible to prevent the oxygen barrier layer 15 from becoming excessively thick.
Here, the "thickness of the oxygen barrier layer 15" means the thickness of the entire oxygen barrier layer 15, and for example, the thickness of the oxygen barrier layer 15 composed of a plurality of layers is all that constitute the oxygen barrier layer 15. Means the total thickness of the layers of.

<Outer layer>
The outer layer 16 is the other outermost layer of the multilayer film 1, and is an exposed surface of the outer layer 16 opposite to the second adhesive layer 132 side (in this specification, it may be referred to as a “second surface”). Reference numeral 16b is the other outermost surface of the multilayer film 1.
In the multilayer film of the present embodiment, the outer layer has an arbitrary configuration, and the multilayer film may or may not have an outer layer, but it is provided in terms of improving the strength of the multilayer film. Is preferable.

Examples of the outer layer 16 include a layer that imparts appropriate strength and pinhole resistance to the multilayer film 1, and those containing nylon are preferable.

The outer layer 16 containing nylon may be the same as the protective layer 14 described above except for the thickness.

The thickness of the outer layer 16 is preferably 2 to 20 μm, more preferably 3 to 16 μm, regardless of whether the multilayer film 1 is for the lid material or the bottom material of the packaging body described later. It is more preferably 3 to 12 μm. When the thickness of the outer layer 16 is at least the lower limit value, the effect of providing the outer layer 16 becomes higher. When the thickness of the outer layer 16 is not more than the upper limit value, it is possible to prevent the outer layer 16 from becoming excessively thick.
Here, the "thickness of the outer layer 16" means the thickness of the entire outer layer 16, for example, the thickness of the outer layer 16 composed of a plurality of layers is the total thickness of all the layers constituting the outer layer 16. means.

<Adhesive layer (first adhesive layer, second adhesive layer)>
Both the first adhesive layer 131 and the second adhesive layer 132 contain an adhesive and adhere two layers adjacent to both sides thereof. More specifically, the first adhesive layer 131 adheres the intermediate layer 12 and the protective layer 14, and the second adhesive layer 132 adheres the oxygen barrier layer 15 and the outer layer 16.
In the multilayer film of the present embodiment, the adhesive layer has an arbitrary structure, and the multilayer film may or may not have an adhesive layer, but in that the structure of the multilayer film is more stable, It is preferable to have it.

The first adhesive layer 131 and the second adhesive layer 132 may be the same as each other or may be different from each other.

The adhesive contained in the first adhesive layer 131 and the second adhesive layer 132 is not particularly limited as long as it can bond the two layers to be bonded with sufficient strength.
Examples of the adhesive include adhesive resins such as olefin resins (that is, polymers of olefins which are one or more types of monomers).

More specific examples of the olefin-based resin include ethylene-based copolymers, propylene-based copolymers, butene-based copolymers, and the like, and polyolefins having a polar group may be used.
The ethylene-based copolymer is a copolymer of ethylene and a monomer other than ethylene.
The propylene-based copolymer is a copolymer of propylene and a monomer other than propylene.
The butene-based copolymer is a copolymer of butene and a monomer other than butene.

Examples of the ethylene-based copolymer include a copolymer of ethylene and a vinyl group-containing monomer.
Examples of the copolymer of ethylene and vinyl group-containing monomer include maleic anhydride graft-modified linear low-density polyethylene (in this specification, it may be abbreviated as "LLDPE-g-MAH") and ethylene. -Vinyl acetate copolymer (sometimes abbreviated as "EVA" in this specification), ethylene-methyl methacrylate copolymer (sometimes abbreviated as "EMMA" in this specification), Ethylene-ethylacrylate copolymer (sometimes abbreviated as "EEA" in this specification), ethylene-methylacrylate copolymer (sometimes abbreviated as "EMA" in this specification), Ethylene-ethylacrylate-maleic anhydride copolymer (sometimes abbreviated as "E-EA-MAH" in the present specification), ethylene-acrylic acid copolymer ("EAA" in the present specification). (May be abbreviated as), ethylene-methacrylic acid copolymer (may be abbreviated as “EMAA” in the present specification), ionomer, ethylene-based thermoplastic elastomer and the like.
As the ionomer contained in the first adhesive layer 131 and the second adhesive layer 132, for example, a copolymer of ethylene and a small amount of acrylic acid or methacrylic acid forms a salt of an acid portion thereof and a metal ion. Some have an ion bridge structure.

The first adhesive layer 131 and the second adhesive layer 132 may each contain only an adhesive (that is, may consist of an adhesive), and the adhesive and other components (the present). In the specification, it may contain (sometimes referred to as "another component") (ie, it may consist of an adhesive and the other component).

The adhesive contained in the first adhesive layer 131 and the second adhesive layer 132 may be only one type, two or more types, or a combination and ratio thereof when there are two or more types. Can be arbitrarily selected according to the purpose.

The other components contained in the first adhesive layer 131 and the second adhesive layer 132 are not particularly limited and may be arbitrarily selected depending on the intended purpose. For example, they may be either resin components or non-resin components.

The other components contained in the first adhesive layer 131 and the second adhesive layer 132 may be only one type, two or more types, or a combination thereof when there are two or more types. And the ratio can be arbitrarily selected according to the purpose.

The ratio of the content of the adhesive to the total mass of the first adhesive layer 131 in the first adhesive layer 131 may be, for example, 85 to 100% by mass.
In other words, the ratio of the content of the other components to the total mass of the first adhesive layer 131 in the first adhesive layer 131 may be 0 to 15% by mass.
The ratio of the contents of these adhesives and the ratio of the contents of the other components are the same in the second adhesive layer 132.

The first adhesive layer 131 and the second adhesive layer 132 may each be composed of one layer (single layer) or may be composed of two or more layers. When the first adhesive layer 131 or the second adhesive layer 132 is composed of a plurality of layers, the plurality of layers may be the same or different from each other, and the combination of the plurality of layers is particularly limited as long as the effects of the present invention are not impaired. Not done.

The thickness of the first adhesive layer 131 and the second adhesive layer 132 may be 2 to 20 μm, respectively, regardless of whether the multilayer film 1 is used for the lid material or the bottom material of the packaging body described later. It is preferably 3 to 17 μm, more preferably 4 to 14 μm. When the thickness of the adhesive layer 131 and the second adhesive layer 132 is at least the above lower limit value, the adhesive strength of the two layers to be adhered becomes higher. When the thickness of the adhesive layer 131 and the second adhesive layer 132 is not more than the upper limit value, it is possible to prevent the adhesive layer 131 and the second adhesive layer 132 from becoming excessively thick.
Here, the "thickness of the first adhesive layer 131" means the thickness of the entire first adhesive layer 131, and for example, the thickness of the first adhesive layer 131 composed of a plurality of layers is the thickness of the first adhesive layer 131. Means the total thickness of all the layers that make up.
The “thickness of the second adhesive layer 132” is also the same as above.

<Other layers>
The multilayer film 1 includes the sealant layer 11, the intermediate layer 12, the first adhesive layer 131, the protective layer 14, the oxygen barrier layer 15, and the second adhesive layer 132 within a range that does not impair the effects of the present invention. , And the outer layer 16, and other layers that do not correspond to any of the above may be provided.
The other layer is not particularly limited and may be arbitrarily selected depending on the intended purpose.
When the multilayer film 1 includes the other layer, an adhesive layer for adhering the other layer to the other layer (for example, a layer similar to the first adhesive layer 131 or the second adhesive layer 132, etc.) ) May be further provided.

The multilayer film of the present embodiment is not limited to the above, and a part of the structure may be changed, deleted or added without departing from the spirit of the present invention.
For example, in the multilayer film 1 shown in FIG. 1, the intermediate layer 12, the protective layer 14, and the oxygen barrier layer 15 are laminated in this order from the sealant layer 11 side to the outer layer 16 side. , The reverse of the above, and other stacking orders may be used.

The thickness of the multilayer film 1 can be arbitrarily selected depending on the intended purpose, and is not particularly limited.
For example, the thickness of the multilayer film 1 may be 40 to 230 μm regardless of whether the multilayer film 1 is for a lid material or a bottom material of a package described later.

The thickness of the multilayer film 1 for the bottom material is preferably 100 to 230 μm, more preferably 115 to 200 μm, and even more preferably 130 to 170 μm. When the thickness of the multilayer film 1 for the bottom material is at least the above lower limit value, the rigidity of the package becomes higher. When the thickness of the multilayer film 1 for the bottom material is not more than the upper limit value, it is possible to prevent the package from becoming excessively thick.

The thickness of the multilayer film 1 for the lid material is preferably 40 to 140 μm, more preferably 55 to 125 μm, and even more preferably 70 to 110 μm. When the thickness of the multilayer film 1 for the lid material is at least the above lower limit value, the rigidity of the package becomes higher. When the thickness of the multilayer film 1 for the lid material is not more than the upper limit value, it is possible to prevent the package from becoming excessively thick.
The package will be described in detail later.

The multilayer film 1 is preferably transparent. A package using the transparent multilayer film 1 as either one or both of the lid material and the bottom material is useful in that the object to be packaged (stored object) can be easily visually recognized from the outside of the package. Is.

<< Manufacturing method of multilayer film >>
The multilayer film of the present embodiment is, for example, a feed block method in which a resin or a resin composition used as a material for forming each layer is melt-extruded using several extruders, or a coextrusion T-die method such as a multi-manifold method. , Air-cooled or water-cooled co-extrusion inflation method or the like.

Further, in the multilayer film of the present embodiment, a resin, a resin composition or the like which is a material for forming any of the layers in the multilayer film is coated on the surface of another layer for forming the multilayer film, if necessary. It can also be produced by forming a laminated structure in a multilayer film and, if necessary, further laminating layers other than these so as to have a desired arrangement form.

Further, in the multilayer film of the present embodiment, two or more films for forming any two or more layers are separately prepared in advance, and these films are extruded by a dry laminating method using an adhesive. It can also be produced by laminating and laminating by any of a laminating method, a hot melt laminating method and a wet laminating method, and if necessary, further laminating layers other than these so as to have a desired arrangement form. At this time, as the adhesive, an adhesive capable of forming the adhesive layer may be used.

Further, in the multilayer film of the present embodiment, as described above, two or more films separately prepared in advance are laminated by laminating them by a thermal (heat) laminating method or the like without using an adhesive. If necessary, it can also be manufactured by further laminating layers other than these so as to have a desired arrangement form.

When producing the multilayer film of the present embodiment, two or more of the methods for forming any layer (film) in the multilayer film described above may be combined.

<< Packaging >>
The package according to one embodiment of the present invention includes the above-mentioned multilayer film for meat packaging according to one embodiment of the present invention.
By providing the multilayer film, the package of the present embodiment can suppress the generation of drip from the meat during packaging and storage. Further, in the package of the present embodiment, the so-called self-weld property, in which the adhesion of the non-sealed portion is stably maintained, is high. Further, the package of the present embodiment has high pinhole resistance. Therefore, the package of the present embodiment has a high meat packaging effect.

FIG. 2 is a cross-sectional view schematically showing a package according to an embodiment of the present invention.
In the drawings after FIG. 2, the same components as those shown in the already explained figures are designated by the same reference numerals as in the case of the already explained figures, and detailed description thereof will be omitted.

The package 101 shown here is configured to include a lid material 3 and a bottom material 2.
The lid material 3 is in the form of a sheet, and is usually preferably transparent.
A recess 20 is formed in the bottom material 2. The bottom material 2 is obtained by deep drawing a film, and is usually preferably transparent.
Since either one or both of the lid material 3 and the bottom material 2 is transparent, the stored object 9 packaged in the package 101 can be easily visually recognized from the outside of the package 101.

In the package 101, one surface (sometimes referred to as a "first surface" in the present specification) 2a of the region excluding the recess 20 of the bottom material 2 and one surface of the lid material 3 (the present specification). 3a (which may be referred to as a "first surface") is a sealing surface and faces each other. The first surface 2a of the bottom material 2 is a surface on the side where the stored object 9 is exposed in a state where the stored object 9 is stored in the recess 20 without forming the package 101.

Further, the package 101 is composed of a seal of the lid material 3 and the bottom material 2. More specifically, the first surface 2a of the region excluding the recess 20 of the bottom material 2 and the first surface 3a of the lid material 3 are overlapped and sealed to each other at their peripheral edges, and as a result, the bottom In the region of the recess 20 of the material 2, a storage portion 101a is formed between the first surface 2a of the bottom material 2 and the first surface 3a of the lid material 3. Then, the stored object 9 is stored in the storage portion 101a. Meat is suitable as the stored material 9.

The peripheral edge of the package 101 is a seal portion 1011. In the package 101, the region closer to the storage portion 101a than the seal portion 1011 and not included in the storage portion 101a is the non-seal portion 1012. In the non-sealed portion 1012, the bottom material 2 and the lid material 3 are not sealed or are in a lightly sealed state, and due to the effect of decompression by vacuuming in the storage portion 101a at the time of packaging, It is in close contact.
When the package 101 is viewed in a plan view from above the lid material 3 side or above the bottom material 2 side thereof, the unsealed portion 1012 exists in the package 101 so as to surround the storage portion 101a. The sealed portion 1011 exists so as to surround the non-sealed portion 1012.

In the package 101, either one or both of the lid material 3 and the bottom material 2 is made of the above-mentioned multilayer film for meat packaging according to the embodiment of the present invention. As the multilayer film, for example, the multilayer film 1 shown in FIG. 1 can be used, but the multilayer film 1 is not limited thereto.
In FIG. 2, when either one or both of the lid material 3 and the bottom material 2 is the multilayer film, the distinction between the layers in the multilayer film is omitted.

For example, when the lid material 3 is made of the multilayer film 1, the first surface 3a of the lid material 3 corresponds to the first surface 11a of the sealant layer 11 in the multilayer film 1, and the first surface 3a of the lid material 3 The surface on the opposite side (sometimes referred to as the "second surface" in the present specification) 3b corresponds to the second surface 16b of the outer layer 16 in the multilayer film 1.
Similarly, when the bottom material 2 is made of the multilayer film 1, the first surface 2a of the bottom material 2 corresponds to the first surface 11a of the sealant layer 11 in the multilayer film 1, and the first surface of the bottom material 2 The surface opposite to 2a (sometimes referred to as the "second surface" in the present specification) 2b corresponds to the second surface 16b of the outer layer 16 in the multilayer film 1.

By using the packaging body 101 in which one or both of the lid material 3 and the bottom material 2 is the multilayer film, when the stored material 9 is meat, it is being stored in the storage unit 101a. The generation of drip from the stored material (meat) 9 is suppressed. Further, in the package 101, the adhesion of the non-sealed portion 1012 is stably maintained. Further, in the package 101, the portion made of the multilayer film has high pinhole resistance.
From the viewpoint of increasing these effects, it is preferable that in the package 101, both the lid material 3 and the bottom material 2 are made of the above-mentioned multilayer film for meat packaging according to the embodiment of the present invention.

In the package 101, the lid material 3 and the stored object 9 are typically in direct contact with each other. Then, the region of the recess 20 of the bottom material 2, particularly the region of the bottom of the recess 20 (for example, the region of the recess 20 facing the lid material 3) and the stored object 9 are in direct contact with each other. In FIG. 2, in the region of the recess 20 of the bottom material 2, the side surface portion and the stored object 9 are not in direct contact with each other, and a gap is seen, but they may be in direct contact with each other.
That is, the stored material 9 is in direct contact with the sealant layer containing the ionomer, and when the stored material 9 is meat due to the action of the ionomer, the stored material (meat) stored in the storage unit 101a. It is presumed that the occurrence of drip from 9 is suppressed.

Further, in the unsealed portion 1012 of the package 101, the bottom material 2 and the lid material 3 are in close contact with each other, and one or both of these contact surfaces contain an ionomer, and the action of the ionomer causes the non-sealing. It is presumed that the adhesion of the site 1012 is stably maintained.

In the packaging body 101, when the lid material 3 is not made of the multilayer film for meat packaging according to the above-described embodiment of the present invention, the lid material 3 is as long as it can be used in a normal deep-drawing packaging bag. Good. Examples of such a lid material 3 include those made of a single-layer or multi-layer resin film.
In the package 101, when the bottom material 2 is not made of the multilayer film for meat packaging according to the above-described embodiment of the present invention, the bottom material 2 is as long as it can be used in a normal deep-drawn packaging bag. Good. Examples of such a bottom material 2 include a single-layer or multi-layer resin film formed by deep drawing.

In the packaging body 101, when the lid material 3 or the bottom material 2 is made of the multilayer film for meat packaging according to the above-described embodiment of the present invention, the thickness of the lid material 3 or the bottom material 2 is the above-described above. It is the same as the thickness of the multilayer film.
In the package 101, when the lid material 3 and the bottom material 2 are both made of the multilayer film, the thickness of the lid material 3 and the bottom material 2 is within the numerical range of the thickness of the multilayer film described above. Moreover, it is preferable that the thickness of the lid material 3 is thinner than the thickness of the bottom material 2.
When the lid material 3 or the bottom material 2 is made of another film instead of the multilayer film, the thickness of the lid material 3 or the bottom material 2 may be the same as the thickness of the multilayer film.

The package of the present embodiment is not limited to the above, and a part of the package may be changed, deleted or added without departing from the spirit of the present invention.

<< Manufacturing method of packaging >>
The packaging body of the present embodiment can be manufactured by superimposing the lid material and the bottom material so as to form the storage portion and heat-sealing them.
At the time of manufacturing the package, the stored items are stored in the storage portion before the heating seal between the lid material and the bottom material. Then, the lid material and the bottom material are heat-sealed while the inside of the storage portion is evacuated.

Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the present invention is not limited to the examples shown below.

<< Manufacture of multilayer films and packaging >>
[Example 1]
A multilayer film having the structure shown in FIG. 1 and a package having the structure shown in FIG. 2 were manufactured by the procedure shown below.

<Manufacturing of multilayer film for bottom material>
As the resin constituting the sealant layer, the base resin is ethylene- (meth) acrylic acid copolymer (EMAA) and the metal ion is zinc ion (Zn ²⁺ ). Ionomer (Mitsui / DuPont Polychemical Co., Ltd. "Himilan 1855"") Was prepared.
An ethylene- (meth) acrylic acid copolymer (“Nucrel AN4901-1C” manufactured by Mitsui / DuPont Polychemical Co., Ltd.) was prepared as a resin constituting the intermediate layer.
An acid-modified polyethylene composition (“Admer NF536” manufactured by Mitsui Chemicals, Inc.) was prepared as an adhesive resin constituting the first adhesive layer and the second adhesive layer.
6-Nylon (“UBE Nylon 1030B2” manufactured by Ube Industries, Ltd.) was prepared as a resin constituting the protective layer and the outer layer.
As a resin constituting the oxygen barrier layer, an ethylene-vinyl acetate copolymer saponified product (“Eberle J171B” manufactured by Kuraray Co., Ltd.) was prepared.

Next, the sealant layer, the intermediate layer, the first adhesive layer, the protective layer, the oxygen barrier layer, the second adhesive layer and the outer layer were co-extruded in this order to produce a multilayer film for a bottom material.
The obtained multilayer film has a sealant layer (thickness 30 μm), an intermediate layer (thickness 49.5 μm), a first adhesive layer (thickness 10.5 μm), a protective layer (thickness 30 μm), and an oxygen barrier layer (thickness). The thickness is 150 μm, which is composed of a second adhesive layer (thickness 12 μm) and an outer layer (thickness 10.5 μm) laminated in this order in this order.

<Manufacturing of multilayer film for lid material>
The multilayer film for the lid material was produced by the same method as in the production of the multilayer film for the bottom material described above, except that the amount of the resin used to form each layer was changed.
The obtained multilayer film has a sealant layer (thickness 18 μm), an intermediate layer (thickness 29.7 μm), a first adhesive layer (thickness 6.3 μm), a protective layer (thickness 18 μm), and an oxygen barrier layer (thickness). 4.5 μm), the second adhesive layer (7.2 μm thick) and the outer layer (6.3 μm thick) are laminated in this order in this order, with a thickness of 90 μm. is there.

<Manufacturing of packaging>
The multilayer film for the bottom material obtained above was deep-drawn and molded to produce the bottom material. The outer shape of the recess in the bottom material to be the storage portion was a square columnar with a size of 15 cm × 11 cm × 2.5 cm.
Next, raw horse meat having a size one size smaller than this recess was stored as meat in the recess in the bottom material obtained above. In this state, the surface of the bottom material on which the meat is exposed (that is, the first surface) and the surface of the lid material (that is, the first surface) are overlapped, and the inside of the recess is evacuated. At the same time, the peripheral portions of the bottom material and the lid material were heat-sealed at 115 ° C. to form a storage portion and the meat was sealed in the storage portion. At this time, the area between the heat-sealed peripheral edge portion and the storage portion was designated as the unsealed portion.
From the above, a package in which meat is stored in the storage portion is manufactured.

[Example 2]
<Manufacturing of multilayer film for bottom material>
As the resin constituting the sealant layer, the base resin is an ethylene-methacrylic acid copolymer instead of the ionomer in which the base resin is an ethylene-methacrylic acid copolymer (EMAA) and the metal ion is a zinc ion (Zn ²⁺ ). (EMAA), and the bottom material is the same as in Example 1 except that an ionomer (“Himilan 1707” manufactured by Mitsui / Dupont Polychemical Co., Ltd.) is used in which the metal ion is sodium ion (Na ⁺ ). Manufactured a multilayer film for use.
The obtained multilayer film has a sealant layer (thickness 30 μm), an intermediate layer (thickness 49.5 μm), a first adhesive layer (thickness 10.5 μm), a protective layer (thickness 30 μm), and an oxygen barrier layer (thickness). The thickness is 150 μm, which is composed of a second adhesive layer (thickness 12 μm) and an outer layer (thickness 10.5 μm) laminated in this order in this order.

<Manufacturing of multilayer film for lid material>
As the resin constituting the sealant layer, the base resin is an ethylene-methacrylic acid copolymer instead of the ionomer in which the base resin is an ethylene-methacrylic acid copolymer (EMAA) and the metal ion is a zinc ion (Zn ²⁺ ). (EMAA), and the lid material is the same method as in Example 1 except that an ionomer (“Himilan 1707” manufactured by Mitsui-Dupont Polychemical Co., Ltd.) is used in which the metal ion is sodium ion (Na ⁺ ). Manufactured a multilayer film for use.
The obtained multilayer film has a sealant layer (thickness 18 μm), an intermediate layer (thickness 29.7 μm), a first adhesive layer (thickness 6.3 μm), a protective layer (thickness 18 μm), and an oxygen barrier layer (thickness). 4.5 μm), the second adhesive layer (7.2 μm thick) and the outer layer (6.3 μm thick) are laminated in this order in this order, with a thickness of 90 μm. is there.

<Manufacturing of packaging>
A package was produced by the same method as in Example 1 except that the multilayer film for the bottom material and the multilayer film for the lid material obtained above were used.

[Comparative Example 1]
<Manufacturing of multilayer film for bottom material>
As the resin constituting the sealant layer, linear low density polyethylene (LLDPE) (LLDPE) (LLDPE) instead of ionomer in which the base resin is ethylene-methacrylic acid copolymer (EMAA) and the metal ion is zinc ion (Zn ²⁺ ). A multilayer film for bottom material was produced by the same method as in Example 1 except that "Ube-Maruzen Polyethylene" Umerit 1520F ") was used.
The obtained multilayer film has a sealant layer (thickness 30 μm), an intermediate layer (thickness 49.5 μm), a first adhesive layer (thickness 10.5 μm), a protective layer (thickness 30 μm), and an oxygen barrier layer (thickness). The thickness is 150 μm, which is composed of a second adhesive layer (thickness 12 μm) and an outer layer (thickness 10.5 μm) laminated in this order in this order.

<Manufacturing of multilayer film for lid material>
As the resin constituting the sealant layer, linear low density polyethylene (LLDPE) (LLDPE) (LLDPE) (LLDPE) instead of ionomer in which the base resin is ethylene-methacrylic acid copolymer (EMAA) and the metal ion is zinc ion (Zn ²⁺ ). A multilayer film for a lid material was produced by the same method as in Example 1 except that "Umerit 1520F" manufactured by Ube Maruzen Polyethylene Co., Ltd. was used.
The obtained multilayer film has a sealant layer (thickness 18 μm), an intermediate layer (thickness 29.7 μm), a first adhesive layer (thickness 6.3 μm), a protective layer (thickness 18 μm), and an oxygen barrier layer (thickness). 4.5 μm), the second adhesive layer (7.2 μm thick) and the outer layer (6.3 μm thick) are laminated in this order in this order, with a thickness of 90 μm. is there.

<Manufacturing of packaging>
A package was produced by the same method as in Example 1 except that the multilayer film for the bottom material and the multilayer film for the lid material obtained above were used.

<< Evaluation of packaging >>
<Evaluation of the effect of suppressing the occurrence of drip>
The package containing the meat obtained above was stored at 20 ° C. for 48 hours.
Next, the package after storage was visually observed, and the degree of drip from the meat was evaluated according to the following criteria. The results are shown in Table 1.
(Evaluation criteria)
A: Almost or no drip is observed.
B: A small amount of drip is observed, but the appearance of the packaged meat is not impaired.
C: A large amount of drip is observed, and the appearance of the packaged meat is impaired.

<Evaluation of adhesion of non-sealed parts in the package>
At the time of the above-mentioned "evaluation of the effect of suppressing the occurrence of drip", the adhesion of the non-sealed portion in the package was evaluated by the following criteria by visual observation at the same time. The results are shown in Table 1.
(Evaluation criteria)
A: Adhesion of the non-sealed part is maintained.
B: Peeling is observed in a small part of the non-sealed part, but almost or no drip accumulation is observed in the peeled part.
C: Clear peeling is observed at the non-sealed site, and drip accumulation is clearly observed at the peeled site.

<Evaluation of the effect of suppressing the occurrence of pinholes in the package>
At the same time as the above-mentioned "evaluation of the effect of suppressing the occurrence of drip", the effect of suppressing the occurrence of pinholes in the package was evaluated by the following criteria by visual observation. The results are shown in Table 1.
(Evaluation criteria)
A: No pinholes are found.
B: One or more pinholes are recognized.

As is clear from the above results, in the packages of Examples 1 and 2, the evaluation results of the effect of suppressing the occurrence of drip and the adhesion of the non-sealed portion in the package are both good, particularly. The package of Example 1 had a better evaluation result than the package of Example 2. In both Examples 1 and 2, the sealant layer of the multilayer film for the bottom material and the sealant layer of the multilayer film for the lid material are both made of ionomer, but in the ionomer of Example 1, the base resin is EMAA. It was an ionomer whose metal ion was Zn ²⁺ .

On the other hand, in the package of Comparative Example 1, the evaluation results of the effect of suppressing the occurrence of drip and the adhesion of the non-sealed portion in the package were inferior. In Comparative Example 1, neither the sealant layer of the multilayer film for the bottom material nor the sealant layer of the multilayer film for the lid material contained ionomers.

On the other hand, in the packages of Examples 1 and 2 and Comparative Example 1, the effect of suppressing the occurrence of pinholes was good. In these examples and comparative examples, the protective layer contained nylon.

The present invention can be used for a package used for storing meat.

1 ... Multilayer film for meat packaging 11 ... Sealant layer 12 ... Intermediate layer 131 ... First adhesive layer 14 ... Protective layer 15 ... Oxygen barrier layer 132 ... Second adhesive layer 16 ... Outer layer 101 ... Package 2 ... Bottom material 3 ... Lid material 1011 ... Sealed part of the package 1012 ... Non-sealed part of the package 101a ... Storage of the package Part 9 ・ ・ ・ Stored items (meat)
20 ... Recessed bottom material

Claims (5)

With a sealant layer and a protective layer,
The protective layer contains nylon and
The sealant layer is a multilayer film for meat packaging containing ionomer. The multilayer film for meat packaging according to claim 1, wherein the metal ions constituting the ionomer are zinc ions or sodium ions. The multilayer film for meat packaging according to claim 1 or 2, wherein the ionomer is an ethylene-based copolymer ionomer. A packaging body comprising the multilayer film for meat packaging according to any one of claims 1 to 3. The package includes a lid material and a bottom material.
The packaging body is composed of a seal for the lid material and the bottom material.
The package according to claim 4, wherein either one or both of the lid material and the bottom material is made of the multilayer film for meat packaging.

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