JP2006256144A - Coextruded film for deep drawing molding, bottom material for deep drawing pakage, and deep drawing package - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film for deep drawing molding which is heat-sealable with a nonwoven fabric of high density polyethylene and has good opening properties. <P>SOLUTION: The film comprises at least a polyamide resin layer and an easily peelable layer which is heat-sealble with a polyethylene nonwoven fabric or sterilization paper at 135°C or below and has cohesion breakage properties. The easily peelable layer preferably comprises a resin composition A in which a main component is at least one selected from the group consisting of LLDPE of Vicat softening point 90°C or below, EVA, EAA, EEA, EMAA, EMMA and EMA, having melting points of 100°C or lower and the ionomers of the above polymers and a resin composition B in which a main component is PP or PB. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention mainly relates to a co-extruded film for deep drawing, a bottom material for a deep drawing package, and a deep drawing package that can be suitably used for packaging business gauze, cotton swabs, and the like.

  In recent years, business-use gauze, cotton swabs and the like housed in deep-drawn packages have been distributed at pharmacies, supermarkets, convenience stores and the like. For example, as shown in FIG. 1, the deep-drawn package 1 is formed by joining a bottom material 20 having a recess 30 at a substantially central portion and a high-density polyethylene nonwoven fabric or a lid 10 made of sterilized paper by heat sealing or the like. It is obtained. The gauze 40 and the like are accommodated in the recess 30 of the bottom material 20, and the bottom material 20 and the lid material 10 are heat sealed by the heat seal portion 50 (see FIG. 2) and accommodated in the bottom material 20.

Conventionally, as the bottom material 20 for a deep-drawn package, a laminate film obtained by laminating (laminating) a nylon resin (Ny) film and a heat-sealable resin film has been widely used (for example, Patent Document 1). The reason is that a film having this configuration can be heat-sealed at a relatively low temperature with a lid (for example, a high-density polyethylene nonwoven fabric or sterilized paper) and can impart easy peel properties. However, the resin used in the sealing layer of the laminate film so far is a type that imparts easy peelability by interfacial peeling from the lid material, so easy peel strength due to differences in sealing temperature, pressure, etc. in the manufacturing process Therefore, there is a problem that it is difficult to obtain uniform easy peel strength. In addition, when the easy peel strength is large, for example, in a deep-drawn molded body using a lid made of polyethylene non-woven fabric or sterilized paper, the strength of the lid is significantly weaker than that of a general plastic lid, There was a problem that the lid material was torn during opening, making it difficult to take out the contents. Moreover, since the laminating method was used in the manufacturing method of a deep drawing package, there also existed the economical problem that the cost at the time of film manufacture increased.
Japanese Patent Laid-Open No. 11-115119

  The present invention is intended to solve the above-mentioned problems of the prior art, and an object of the present invention is to achieve a depth that has good easy peel properties and can be heat-sealed with a polyethylene nonwoven fabric or sterilized paper at a temperature of 135 ° C. or lower. The object is to provide a co-extruded film for drawing.

  Another object of the present invention is to provide a bottom material for a deep-drawn package body and a deep-drawn package body comprising the coextruded film for deep-drawing of the present invention.

  The above object of the present invention is to provide the following coextruded film for deep drawing (hereinafter also referred to as “film of the present invention”), a bottom material for deep drawn packaging (hereinafter also referred to as “the bottom material of the present invention”) and deep drawn packaging. It is achieved by the body (hereinafter also referred to as “packaging body of the present invention”).

  The first object of the present invention is a polyamide resin layer (hereinafter also referred to as “PA layer”) and an easy peel that can be heat-sealed with a polyethylene non-woven fabric or sterile paper at a temperature of 135 ° C. or less and has cohesive failure. It is achieved by a coextruded film for deep drawing characterized by having at least a layer (hereinafter also referred to as “EP layer”).

  Here, “having cohesive failure” means that when the deep-drawn package is opened, the EP layer itself is destroyed and peeled off, and the EP layer remains on both the bottom material side and the lid material side. . In addition, “heat-sealable with polyethylene non-woven fabric or sterilized paper” means that when heat-sealed at a predetermined temperature, the EP layer and polyethylene non-woven fabric or sterilized paper (lid material) can be joined with a desired easy peel strength. Say.

In the present invention, the EP layer is based on the total mass of the EP layer (100% by mass), and the resin composition A of 40% by mass to 80% by mass and 20% by mass to 60% by mass shown below. It is preferable that the resin composition B is used.
Resin composition A: linear low density polyethylene (LLDPE) having a main component of Vicat softening point of 90 ° C. or lower, ethylene-vinyl acetate copolymer (EVA) having a melting point of 100 ° C. or lower, ethylene-acrylic acid having a melting point of 100 ° C. or lower Copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA) having a melting point of 100 ° C. or lower, ethylene-methacrylic acid copolymer (EMAA) having a melting point of 100 ° C. or lower, ethylene-methyl methacrylate having a melting point of 100 ° C. or lower Resin composition which is at least one selected from the group consisting of a copolymer (EMMA), an ethylene-methyl acrylate copolymer (EMA) having a melting point of 100 ° C. or less, and these ionomers Resin composition B: Main component is polypropylene (PP) or polybutene (PB) resin composition

  Here, the “main component” refers to a component contained in a content of 50% by mass or more, preferably 70% by mass or more, and more preferably 85% by mass or more, among the components constituting the entire resin composition.

  The film of the present invention may have at least one polypropylene resin layer (hereinafter also referred to as “PP layer”) on the surface of the PA layer opposite to the surface on the EP layer side.

  The film of the present invention comprises at least one ethylene-vinyl acetate copolymer layer (hereinafter referred to as “EVA layer”) between the PA layer and the EP layer and / or between the PA layer and the PP layer. Or a polyethylene resin layer (hereinafter also referred to as “PE layer”).

  The film of the present invention preferably has at least one adhesive resin layer between the PA layer and the EP layer and / or between the PA layer and the PP layer.

  In the film of the present invention, the easy peel strength of the EP layer is preferably from 0.8 N / 15 mm width to 5.0 N / 15 mm width at 25 ° C.

  The second object of the present invention is achieved by a bottom material for a deep-drawn package and a deep-drawn package formed by the above-mentioned deep-drawing co-extruded film.

  The package of the present invention is a deep-drawn package using the above-mentioned bottom of the present invention as a deep-drawn package and a polyethylene nonwoven fabric or sterile paper as a deep-drawn lid. Is preferred.

  The film of the present invention has at least a PA layer and an EP layer that can be heat-sealed with a polyethylene nonwoven fabric or sterilized paper at a temperature of 135 ° C. or less and has cohesive failure. With this configuration, if a deep-drawn package is formed according to the present invention, deep-draw molding that can impart an easy peel property that can open the bottom and the lid without breaking the nonwoven fabric or sterilized paper at the time of opening. A coextruded film optimum for the above can be obtained.

  Moreover, since the bottom material for deep-drawn packaging bodies of the present invention is made of the film of the present invention, when a lid made of polyethylene non-woven fabric or sterilized paper is used, the desired easy peel property to the lid is achieved. A deep-drawn package that can be applied can be provided.

  Hereinafter, the coextruded film for deep drawing, the bottom material for deep drawing package, and the deep drawing package of the present invention will be described in more detail.

[Coextruded film for deep drawing]
The film of the present invention has at least a PA layer and an EP layer that can be heat-sealed with a polyethylene nonwoven fabric or sterilized paper at 135 ° C. or lower and has cohesive failure.

<PA layer>
In the present invention, it is important to provide at least one PA layer for the purpose of imparting pinhole resistance and deep drawability.

  The type of PA used in the PA layer is not particularly limited, but nylon resin (Ny) is preferable from the viewpoint of pinhole resistance. Examples of Ny include polymers of condensed units such as 6 nylon, 66 nylon, 69 nylon, 6-66 nylon, 12 nylon, 11 nylon, 610 nylon, 612 nylon, 6I-6T nylon, and MXD6 nylon, or two of these. Copolymers with the above, and mixtures thereof can also be mentioned. Among them, it is preferable to use 6 nylon or 6-66 nylon.

  The thickness of the PA layer is preferably at least 5 μm, more preferably 10 μm or more, and even more preferably 15 μm or more from the viewpoint of pinhole resistance and moldability. The thickness of the PA layer is preferably 200 μm or less, more preferably 180 μm or less, and even more preferably 150 μm or less. When the lower limit value of the thickness of the PA layer is 5 μm, good pinhole resistance can be obtained, and when the upper limit value is 200 μm, the thermoformability of the film can be maintained well.

<EP layer>
It is important that the film of the present invention has an EP layer that can be heat-sealed with a polyethylene non-woven fabric or sterilized paper at a temperature of 135 ° C. or less as the innermost layer and has cohesive failure. That is, in the EP layer, the polyethylene nonwoven fabric or sterilization is performed at a sealing temperature of 135 ° C. or lower, preferably 133 ° C. or lower, more preferably 130 ° C. or lower, and 100 ° C. or higher, preferably 110 ° C. or higher, more preferably 115 ° C. or higher. It is important to use a resin that can be heat sealed to paper. By configuring the EP layer with such a resin, when the heat-sealing is performed with a polyethylene woven fabric or sterilized paper using a deep drawing packaging machine, the polyethylene non-woven fabric is melted and the non-woven fabric side seal portion becomes transparent. It can prevent the appearance from deteriorating and the sterilized paper from being torn when opened.

  The resin constituting the EP layer is not particularly limited as long as it is heat-sealable with a polyethylene nonwoven fabric or sterilized paper at a temperature of 135 ° C. or lower and has a cohesive failure. The EP layer can be composed of, for example, a resin composition A and a resin composition B described below which are different from each other.

  Examples of the resin composition A include linear low density polyethylene (LLDPE) having a Vicat softening point of 90 ° C. or lower, an ethylene-vinyl acetate copolymer (EVA) having a melting point of 100 ° C. or lower, and ethylene having a melting point of 100 ° C. or lower. -Acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA) having a melting point of 100 ° C or lower, ethylene-methacrylic acid copolymer (EMAA) having a melting point of 100 ° C or lower, ethylene having a melting point of 100 ° C or lower- It is possible to use at least one resin composition selected from the group consisting of a methyl methacrylate copolymer (EMMA), an ethylene-methyl acrylate copolymer (EMA) having a melting point of 100 ° C. or less, and these ionomers. Among them, an ethylene-vinyl acetate copolymer (EVA) having a melting point of 100 ° C. or lower can be suitably used.

  As the resin composition B, a resin composition whose main component is polypropylene (PP) or polybutene (PB) can be used. As the PP constituting the main component of the resin composition B, any of random copolymers, homopolymers, block copolymers and the like can be used, and among them, random copolymers can be preferably used.

  Resin compositions A and B constituting the EP layer may contain other components in addition to the above main components as long as the effects of the present invention are not impaired. Examples of other components include very low density polyethylene (VLDPE), polyamide, and polyester.

  The content of the resin composition A in the EP layer is 40% by mass or more, preferably 50% by mass or more of the resin composition A with respect to the mass (100% by mass) of the entire EP layer from the viewpoint of sealing properties and unsealing properties. It is desirable that the content be 80% by mass or less, preferably 75% by mass, and more preferably 60% by mass or less. From the same viewpoint, the content of the resin composition B in the EP layer is 20% by mass or more, preferably 25% by mass or more, more preferably 40% by mass or more, and 60% by mass or less, preferably 50% by mass or less. It is desirable. By setting the content of the resin composition A to 40% by mass or more (that is, the content of the resin composition B in the EP layer is 60% by mass or less), it is possible to maintain good heat sealability. On the other hand, when the content of the resin composition A in the EP layer is 80% by mass or less (that is, the content of the resin composition B in the EP layer is 20% by mass or more), an appropriate easy peel strength can be obtained. Good openability is obtained.

  The thickness of the EP layer is 3 μm or more, preferably 4 μm or more, more preferably 5 μm or more, and 20 μm or less, preferably 15 μm or less, more preferably 10 μm or less from the viewpoint of film forming properties and peel appearance. Is desirable. By setting the thickness of the EP layer to 3 μm or more, stable film forming properties can be obtained. On the other hand, when the thickness of the EP layer is 20 μm or less, fluffing and film residue can hardly occur during peeling, and a good peel appearance can be obtained.

  The easy peel strength of the EP layer is 0.8 N / 15 mm width or more, preferably 1.0 N / 15 mm width or more, and 5.0 N / 15 mm width at 25 ° C. in terms of the balance between easy opening and sealing properties. Hereinafter, it is preferably 3.0 N / 15 mm width or less. The easy peel strength was obtained by cutting the seal portion of the deep drawn package formed of the film of the present invention into a strip shape having a width of 15 mm, and peeling the lid material and the bottom material at a speed of 200 mm / min using a tensile tester. It can be obtained from the maximum load when.

PE that constitutes a polyethylene non-woven fabric is heat-sealable with the EP layer, and when the non-woven fabric is formed, it can exhibit air permeability and properties that prevent the entry of fungi into the container (anti-bacterial properties). If there is, it will not be specifically limited. As such PE, various PEs such as high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDPE) can be used. Among them, HDPE having excellent heat sealability is used. It is preferable. The polyethylene nonwoven fabric preferably has small pores that can exhibit air permeability and antibacterial properties when a deep-drawn package is formed. For example, the polyethylene nonwoven fabric is composed of fibers in a range of 0.00001 dtex or more and less than 20 dtex. It is desirable that the nonwoven fabric has a basis weight of 10 g / m ² or more and less than 500 g / m ² .

Moreover, the sterilized paper to be heat-sealed is not particularly limited as long as it can exhibit air permeability and antibacterial properties. Such a sterilized paper is desirably a sterilized paper having a basis weight of 40 g / m ² or more and less than 300 g / m ² .

<Outer layer and intermediate layer>
In the film of the present invention, an outer layer can be provided on the surface of the PA layer opposite to the surface on the EP layer side. Furthermore, an intermediate layer can be provided between the PA layer and the EP layer. Here, the “outer layer” refers to a single layer or a layer composed of two or more layers provided on the surface of the PA layer opposite to the surface on the EP layer side. The “intermediate layer” refers to a single layer or a layer composed of two or more layers provided between the PA layer and the EP layer or between the PA layer and the outer layer. Below, each layer which comprises an outer layer and an intermediate | middle layer is demonstrated.

(Outer layer)
In the film of the present invention, a propylene layer (PP layer) can be disposed as an outer layer of the PA layer for the purpose of imparting hardness. The kind of PP used in the PP layer is not particularly limited, and examples thereof include a random copolymer, a block copolymer, a homopolymer, or a mixture thereof. Among these, a random copolymer is preferred from the viewpoint of deep drawability. The PP layer has a thickness of 10 μm or more, preferably 20 μm or more, more preferably 25 μm or more, and an upper limit of 100 μm or less, preferably 80 μm or less, and more preferably 60 μm or less, from the viewpoint of film formability.

(Middle layer)
The film of the present invention comprises an ethylene-vinyl acetate copolymer layer (EVA layer) or a polyethylene layer for the purpose of imparting flexibility between the PA layer and the EP layer and / or between the PA layer and the PP layer. (PE layer) can be disposed as an intermediate layer.

  The ethylene content of EVA used in the EVA layer is not particularly limited, but from the viewpoint of film formation stability, it is 1 mol% or more, preferably 1.5 mol% or more, and 20 mol% or less, Preferably it is 15 mol% or less. When the EVA layer is provided, the thickness of the EVA layer is 10 μm or more, preferably 20 μm or more, more preferably 25 μm or more, and the upper limit is 100 μm or less, preferably 80 μm or less, more preferably 60 μm or less from the viewpoint of film forming properties. It is desirable.

  When a PE layer is disposed as an intermediate layer, the PE used in the PE layer is not particularly limited. For example, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), high density polyethylene ( HDPE) or a mixture of LDPE and HDPE can be used. The mixing ratio in the mixture of LDPE and HDPE can be appropriately determined for the purpose of imparting desired flexibility. For example, the mixing ratio of LDPE and HDPE is 40 to 80:60 to 20, preferably 50 to 80 by mass ratio. : 50 to 20, more preferably 60 to 80: 40 to 20.

  LDPE or LLDPE having a density of 0.90 or more is preferable, and HDPE having a density of 0.94 or more is preferably used. By using a high-density material, moderate hardness can be imparted to the PE layer while maintaining flexibility. When the PE layer is provided, the thickness of the PE layer is 10 μm or more, preferably 20 μm or more, more preferably 25 μm or more, and the upper limit is 100 μm or less, preferably 80 μm or less, more preferably 60 μm or less.

(Adhesive resin layer)
In the film of the present invention, an adhesive resin layer can be disposed in the intermediate layer or the outer layer in order to adhere each layer. The adhesive resin used in the adhesive resin layer is not particularly limited as long as the PA layer, PE layer, and PP layer can be bonded to the required strength, but a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof is preferable. Can be used. Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, citraconic acid and the like. In addition, esters and anhydrides of the unsaturated carboxylic acid can be used as the adhesive resin, and as derivatives, methyl acrylate, methyl methacrylate, ethyl acrylate, propyl acrylate, butyl acrylate, butyl methacrylate, glycidyl acrylate In addition to glycidyl methacrylate, acrylamide, methacrylamide, sodium acrylate, etc., vinyl acetate can be used. As a commercially available adhesive resin, the Mitsui Chemicals make, brand name Admer is mentioned, for example, These can be used conveniently.

  It is preferable that at least one adhesive resin layer is provided between the PA layer and the EP layer and / or between the PA layer and the PP layer from the viewpoint of further increasing the interlayer adhesive strength. Specifically, one or more layers are preferably provided between the PA layer and the EP layer, between the PA layer and the PE layer, between the PA layer and the EVA layer, and between the PA layer and the PP layer.

  The thickness of the adhesive resin layer is not particularly limited as long as each layer can be bonded with a required adhesive strength, but it is 2 μm or more, preferably 3 μm or more, more preferably 5 μm or more, 20 μm or less, preferably 15 μm or less, more preferably 10 μm or less. It is desirable that

<Layer structure>
The layer configuration of the film of the present invention is not particularly limited as long as the PA layer is disposed as the outermost layer and the EP layer is disposed as the innermost layer. For example, when represented by PA layer (A), PE layer (B), EVA layer (C), PP layer (D), EP layer (E) and adhesive resin layer (F), the following layer structure is formed. be able to. Among them, the preferred layer configuration is the following (1), (3), (5) or (7), and the most preferred layer configuration is (1) or (5).

(1) A / F / E
(2) A / F / B / E
(3) A / F / C / E
(4) D / F / A / F / E
(5) D / F / A / F / B / E
(6) D / F / A / F / C / E
(7) A / F / A / F / E
(8) A / F / A / F / B / E
(9) A / F / A / F / C / E
(10) D / A / F / A / F / E
(11) D / A / F / A / F / B / E
(12) D / A / F / A / F / C / E

<Film production method>
The film of the present invention comprises a PA layer and an EP layer, an intermediate layer formed therebetween, and an outer layer formed on the surface of the PA layer opposite to the surface on the EP layer side simultaneously or sequentially. It can be produced by stacking.

  The film of the present invention is prepared by simultaneously co-extruding with an extruder equipped with a die by an existing method such as a T-die method or a tubular method, thereby simultaneously producing a polyamide resin layer, an easy peel layer, an intermediate layer and an outer layer. Can do. In addition, the laminated film can be sequentially produced by separately forming the resin constituting each layer and then laminating them using a press method or a roll nip method.

[Bottom material for deep-drawn packaging and deep-drawn packaging]
For example, as shown in FIG. 1, the film of the present invention is filled with a content 40 such as gauze after deep drawing, covered with a lid material film 10, and the bottom material 20 and the lid material film 10 are heated. It can be used as the deep drawn package 1 by heat-sealing with the seal part 50 (see FIG. 2). In particular, when the film of the present invention is used as the bottom material of a deep drawn package, a good deep drawn package can be obtained. When used as a bottom material for a deep-drawn package, for example, after forming the film of the present invention into a desired shape and size with a deep-drawing mold (film supply step and film forming step), Fill the contents (content filling process), seal with a lid material film from above (cover material film supply process and sealing process), vacuum package (vacuum packaging process), cool (cooling process), By cutting (cutting step), a deep drawn package can be produced.

  The lid material used in the package of the present invention is preferably breathable when the entire package is sterilized with ethylene oxide gas (EOG). From such a viewpoint, a non-woven fabric or sterilized paper made of polyethylene (particularly HDPE) is preferably used as the lid of the deep drawn package of the present invention.

  The package of the present invention heat-seals the lid material 10 (polyethylene non-woven fabric or sterilized paper) and the bottom material 20 of the deep-drawn package of the present invention at a temperature of 135 ° C. or less by an adhesive means such as heat seal. It can be manufactured by heat-sealing in the part 50.

  Examples of the present invention will be described below, but the present invention is not limited thereto.

Example 1
A film having the following layer constitution was obtained by co-extrusion of all layers, and Example 1 was obtained.
Ny (40 μm) / adhesive resin (10 μm) / LLDPE1 (40 μm) / EP1 (10 μm)
Ny: Mitsubishi Engineering Plastics Novamid (6Ny)
Adhesive resin: Admer made by Mitsui Chemicals LLDPE1: Moretec made by Idemitsu Petrochemical EP1: Blend of LLDPE2 (60%) and polybutene (40%) LLDPE2: Moretech made by Idemitsu Petrochemical (Vicat softening point 85 ° C)
Polybutene: Mitsui Chemicals Toughmer

(Example 2)
A film having the following layer constitution was obtained by coextrusion of all layers, and was designated as Example 2.
PP (20 μm) / Adhesive resin (10 μm) / Ny (30 μm) / Adhesive resin (10 μm) / EVA1 (20 μm) / EP2 (10 μm)
PP: Nippon Polypro's Novatec PP
Adhesive resin: Mitsui Chemicals Admer Ny: Mitsubishi Engineering Plastics Novamid (66-Ny ratio of 6-66 copolymerized Ny)
EVA1: Japan Polyethylene Novatec EVA (VAC 5%)
EP2: Blend of EVA2 (60%) and random copolymer PP (40%) EVA2: Nippon Polyethylene Novatec EVA (VAC 15%; melting point 97 ° C.)

(Comparative Example 1)
A film having the following layer structure was obtained by coextrusion of all layers, and was designated as Comparative Example 1.
Ny (40 μm) / adhesive resin (10 μm) / LLDPE1 (40 μm) / EP3 (10 μm)
EP3: Blend of LLDPE1 (60%) and polybutene (40%) with Vicat softening point of 105 ° C

(Comparative Example 2)
A film having the following layer structure was obtained by coextrusion of all layers, and was designated as Comparative Example 2.
PP (20 μm) / Adhesive resin (10 μm) / Ny (30 μm) / Adhesive resin (10 μm) / EVA1 (20 μm) / EP4 (10 μm)
EP4: blend of EVA1 (60%) and random copolymer PP (40%) with a melting point of 105 ° C.

(Comparative Example 3)
A film having the following layer structure was obtained by coextrusion of all layers, and was designated as Comparative Example 3.
PP (50 μm) / Adhesive resin (10 μm) / LLDPE1 (30 μm) / EP2 (10 μm)

(Comparative Example 4)
A film having the following layer structure was obtained by coextrusion of all layers, and was designated as Comparative Example 4.
Ny (40 μm) / adhesive resin (10 μm) / LLDPE1 (40 μm) / LLDPE2 (10 μm)

[Preparation of packed sample]
Using a deep-drawing packaging machine (FV6300 manufactured by Omori Machine Industry Co., Ltd.), the bottom material is produced by deep-drawing into a shape with a length of 160 mm, a width of 120 mm, and a drawing depth of 50 mm, and 50 g of gauze is placed in it to cover the lid. The heat seal part of the frame formed on the outer periphery of the bottom material was sealed. The lid material was a high-density polyethylene nonwoven fabric.

[Evaluation methods]
<Minimum heat seal temperature>
In the deep-drawing packaging machine, the temperature at which the heat sealing is sufficiently performed at the sealing time of 2 seconds was defined as the minimum heat sealing temperature.
<Easy peel strength>
The seal portion of the packed product was cut into a strip shape having a width of 15 mm with respect to the film flow direction, and the maximum load when the lid material and the bottom material were peeled off at a speed of 200 mm / min with a tensile tester was defined as easy peel strength.
<Peelability>
The case where the cover material was not torn when the pack product was peeled by hand was rated as ○, and the case where it was torn was rated as x.
<Deep drawing formability>
When a bottom material having a length of 160 mm, a width of 120 mm, and a drawing depth of 50 mm was formed by deep drawing, “◯” indicates that the bottom material was molded as it was, and “x” indicates that the film could not be formed and the film was broken.
<Appearance>
The high density polyethylene nonwoven fabric of the heat seal part that was white without melting at the time of heat sealing was marked with ◯, and the one that was melted and turned discolored transparent was marked with x.

  From Table 1, since Examples 1 and 2 can be heat-sealed at a temperature of 135 ° C. or less (heat seal temperature: 125 ° C.), the lid material of the nonwoven fabric made of high-density polyethylene does not melt and the easy peel strength Is a strength with good openability, and the lid material was not torn when opened, and the deep drawability was also good.

  On the other hand, in Comparative Examples 1 and 2, since the heat seal temperature exceeded 135 ° C., the lid material of the nonwoven fabric made of high-density polyethylene was melted and became transparent, and the pack appearance was deteriorated. In Comparative Example 3, since there was no polyamide resin layer, the film had no strength, and the film sometimes broke during deep drawing. In Comparative Example 4, the easy peel is an interface peeling type, and the easy peel strength is unstable. Therefore, the lid material may be broken at the time of opening.

It is explanatory drawing which shows the package body before joining. It is explanatory drawing which shows the package body after joining of a cover material and a bottom material.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Deep drawing package 10 Cover material 20 Bottom material 30 Concave part 40 Contents, such as gauze 50 Heat seal part

Claims (8)

  A coextruded film for deep drawing, comprising at least a polyamide resin (PA) layer and an easy peel layer capable of heat sealing with a polyethylene non-woven fabric or sterilized paper at 135 ° C. or less and having cohesive failure . 40 mass% or more and 80 mass% or less of the resin composition A shown below and resin composition of 20 mass% or more and 60 mass% or less of the said easy peel layer on the basis of the mass (100 mass%) of the whole easy peel layer The coextruded film for deep drawing according to claim 1, which is composed of product B.
Resin composition A: linear low density polyethylene (LLDPE) having a main component of Vicat softening point of 90 ° C. or lower, ethylene-vinyl acetate copolymer (EVA) having a melting point of 100 ° C. or lower, ethylene-acrylic acid having a melting point of 100 ° C. or lower Copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA) having a melting point of 100 ° C. or lower, ethylene-methacrylic acid copolymer (EMAA) having a melting point of 100 ° C. or lower, ethylene-methyl methacrylate having a melting point of 100 ° C. or lower Resin composition which is at least one selected from the group consisting of a copolymer (EMMA), an ethylene-methyl acrylate copolymer (EMA) having a melting point of 100 ° C. or less, and these ionomers Resin composition B: Main component is polypropylene (PP) or polybutene (PB) resin composition   3. The coextrusion for deep drawing according to claim 1, wherein at least one polypropylene resin (PP) layer is provided on a surface of the polyamide resin (PA) layer opposite to the surface on the easy peel layer side. the film.   At least one ethylene-vinyl acetate copolymer between the polyamide resin (PA) layer and the easy peel layer and / or between the polyamide resin (PA) layer and the polypropylene resin (PP) layer. The coextruded film for deep drawing according to any one of claims 1 to 3, comprising an (EVA) layer or a polyethylene resin (PE) layer.   The adhesive resin layer is provided between the polyamide resin (PA) layer and the easy peel layer and / or between the polyamide resin (PA) layer and the polypropylene resin (PP) layer. The coextruded film for deep drawing according to any one of 1 to 4.   The coextruded film for deep drawing according to any one of claims 1 to 5, wherein an easy peel strength of the easy peel layer is 0.8 N / 15 mm width or more and 5.0 N / 15 mm width or less at 25 ° C.   A bottom material for a deep-drawn package, which is formed by the coextruded film for deep-drawing molding according to any one of claims 1 to 6.   A deep-drawn package comprising the bottom material according to claim 7 as a bottom material for a deep-drawn package and a polyethylene non-woven fabric or sterilized paper as a lid for the deep-drawn package.

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