JP2022093021A - Barrier film, laminate and packaging container - Google Patents

Abstract

To enhance barrier properties of a barrier film having a sealant film and a vapor-deposited layer.SOLUTION: A barrier film includes: a sealant film having a first face and a second face located on an opposite side of the first face; and a vapor-deposited layer located on the second face. The sealant film includes: a polyolefin resin layer composing the first face; a surface resin layer composing the second face and containing a resin material having a polar group; and an adhesive resin layer located between the polyolefin resin layer and the surface resin layer.SELECTED DRAWING: Figure 1

Description

The present invention relates to barrier films, laminates, and packaging containers.

As a member constituting a packaging container such as a pouch, a laminated body in which a plurality of films are laminated is used. The laminate comprises a substrate and a sealant film.

Barrier properties against oxygen, water vapor, etc. may be required for packaging containers. For example, Patent Document 1 proposes forming a vapor-deposited layer of aluminum on the surface of a sealant film.

Japanese Unexamined Patent Publication No. 2001-179878

If the adhesion between the sealant film and the vapor deposition layer is low, the barrier property is also low.

The present invention has been made in consideration of such a point, and an object of the present invention is to enhance the barrier property of the sealant film and the barrier film provided with the vapor-deposited layer.

The present invention
A sealant film containing a first surface and a second surface located on the opposite side of the first surface, and
A thin-film deposition layer located on the second surface is provided.
The sealant film has a polyolefin resin layer constituting the first surface, a surface resin layer constituting the second surface and containing a resin material having a polar group, and between the polyolefin resin layer and the surface resin layer. A barrier film comprising a located adhesive resin layer.

In the barrier film of the present invention, the resin material may be one or more resin materials selected from ethylene vinyl alcohol copolymer, polyvinyl alcohol, polyester, nylon 6, nylon 6,6, MXD nylon and amorphous nylon. good.

In the barrier film of the present invention, the surface resin layer may contain an ethylene vinyl alcohol copolymer and have a thickness of 3 μm or more, and the adhesive resin layer may have a thickness of 3 μm or more. You may be doing it.

In the barrier film of the present invention, the surface resin layer may contain nylon 6, nylon 6, 6 or MXD nylon and may have a thickness of 2 μm or more.
The adhesive resin layer may have a thickness of 2 μm or more.

In the barrier film of the present invention, the ratio of the thickness of the surface resin layer to the thickness of the sealant film may be 1% or more and 20% or less.

In the barrier film of the present invention, the polyolefin resin layer may be a polypropylene resin layer.

In the barrier film of the present invention, the polypropylene resin layer may include a first copolymer layer and a second copolymer layer, and a homopolymer layer located between the first copolymer layer and the second copolymer layer. good.

In the barrier film of the present invention, the vapor-deposited layer may include a metal layer or an inorganic oxide layer.

In the barrier film of the present invention, the value obtained by dividing the breaking energy of the sealant film by the thickness of the sealant film may be 0.0025 J / μm or more.

The present invention is a laminate comprising the barrier film described above and a base material.

In the laminate of the present invention, the base material may contain a stretched plastic film. In this case, the laminate may include a print layer located between the base material and the barrier film.

In the laminate of the present invention, the base material may contain a stretched plastic film. In this case, the laminate may include an adhesive layer located between the substrate and the barrier film.

In the laminated body of the present invention, the base material may contain paper.

The present invention is a packaging container provided with the above-mentioned laminate.

According to the present invention, the barrier property of the sealant film and the barrier film provided with the vapor-deposited layer can be enhanced.

It is sectional drawing which shows an example of the barrier film in this embodiment. It is sectional drawing which shows an example of the barrier film in this embodiment. It is a figure which shows an example of the vapor deposition apparatus. It is a figure which shows an example of the vapor deposition apparatus. It is sectional drawing which shows an example of the laminated body in this embodiment. It is sectional drawing which shows an example of the laminated body in this embodiment. It is a figure which shows an example of the measuring method of a laminate strength. It is a figure which shows an example of the measuring method of a laminate strength. It is a figure which shows an example of the measurement result of the laminate strength. It is a figure which shows an example of a packaging container. It is a figure which shows an example of a packaging container. It is a figure which shows an example of a packaging container. It is a figure which shows the evaluation result of an Example and a comparative example. It is a figure which shows the evaluation result of an Example and a comparative example.

An embodiment of the present invention will be described. In the drawings attached to the present specification, the scale, aspect ratio, etc. are appropriately changed from those of the actual product and exaggerated for the convenience of illustration and comprehension.

In addition, the terms such as "orthogonal" and "identical" and the values of length and angle used in the present specification to specify the shape and geometric conditions and their degrees are bound by a strict meaning. Interpret without including the range in which similar functions can be expected.

(Barrier film)
FIG. 1 is a cross-sectional view showing an example of the barrier film 10 according to the present embodiment. The barrier film 10 includes a sealant film 20 and a vapor deposition layer 30. The sealant film 20 includes a first surface 20x and a second surface 20y. The second surface 20y is a surface located on the opposite side of the first surface 20x. The thin-film deposition layer 30 is located on the second surface 20y.

As shown in FIG. 1, the sealant film 20 includes a polyolefin resin layer 21, an adhesive resin layer 22, and a surface resin layer 23. The polyolefin resin layer 21 constitutes the first surface 20x. The surface resin layer 23 constitutes the second surface 20y. The adhesive resin layer 22 is located between the polyolefin resin layer 21 and the surface resin layer 23.

FIG. 2 is a cross-sectional view showing another example of the barrier film 10. In the example shown in FIG. 2, the polyolefin resin layer 21 is a polypropylene resin layer. In this case, the polyolefin resin layer 21 may include a first copolymer layer 21a, a homopolymer layer 21b, and a second copolymer layer 21c. The first copolymer layer 21a may constitute the first surface 20x of the sealant film 20. The homopolymer layer 21b is located between the first copolymer layer 21a and the second copolymer layer 21c. The second copolymer layer 21c may be in contact with the adhesive resin layer 22.

Each component of the barrier film 10 will be described in detail.

[Sealant film]
The sealant film 20 is a film produced by co-extrusion. The sealant film 20 is preferably an unstretched film. "Unstretched" is a concept that includes not only a film that is not stretched at all but also a film that is slightly stretched due to the tension applied during film formation.

The breaking strength of the sealant film 20 in at least one direction is, for example, 100 MPa or less, and may be 50 MPa or less. For example, the breaking strength of the sealant film 20 in the flow direction and the vertical direction may be 100 MPa or less, or 50 MPa or less.
The elongation at break of the sealant film 20 in at least one direction is, for example, 300% or more, and may be 350% or more. For example, the tensile elongation of the sealant film 20 in the flow direction and the vertical direction may be 300% or more, or 350% or more.

The breaking strength is the stress applied to the sealant film 20 when the sealant film 20 is broken. The elongation at break is the elongation that occurs in the sealant film 20 when the sealant film 20 is broken. The breaking strength and tensile elongation of the sealant film 20 are measured according to JIS K7127. As the measuring instrument, a Tensilon universal material tester RTC-1310 manufactured by A & D can be used. In the measurement, a sealant film 20 cut into a rectangular film having a width of 10 mm and a length of 150 mm is used as a test piece. The distance at the start of measurement between the pair of chucks holding the test piece is 50 mm. The tensile speed of the test piece is 300 mm / min. The environment at the time of measurement is a temperature of 23 ° C. and a relative humidity of 50% RH.

Next, each layer of the sealant film 20 will be described.

[Polyolefin resin layer]
The polyolefin resin layer 21 contains a polymer synthesized by using an olefin such as ethylene or propylene as a monomer. For example, the polyolefin resin layer 21 contains polyethylene, polypropylene, and the like. The polyolefin resin layer 21 may be a polypropylene resin layer.

The polypropylene contained in the polyolefin resin layer 21 may be either a homopolymer or a copolymer. The copolymer may be either a block copolymer or a random copolymer.

The block copolymer is a copolymer having a polymer block made of propylene and a polymer block made of other α-olefins other than propylene. For example, block copolymers include polymer blocks made of ethylene, butene-1, 4-methyl-1-pentene, etc., in addition to polymer blocks made of propylene. For example, block copolymers include propylene / ethylene block copolymers. The structural formula of the propylene / ethylene block copolymer is shown in the formula (I).

Random copolymers are random copolymers containing propylene and other α-olefins other than propylene. For example, the random copolymer contains ethylene, butene-1, 4-methyl-1-pentene, etc. in addition to propylene. For example, the random copolymer comprises a propylene / ethylene random copolymer. The structural formula of the propylene / ethylene random copolymer is shown in the formula (II). The random copolymer may contain a ternary copolymer.

Homopolymers are polymers of propylene only. The structural formula of the propylene homopolymer is shown in Formula (III).

Homopolymers have higher crystallinity than random polymers. When rigidity, heat resistance and the like are important, it is preferable to use a homopolymer. When impact resistance, sealing property, etc. are important, it is preferable to use a random copolymer or a block copolymer.

The polyolefin resin layer 21 may contain polypropylene derived from biomass. The polyolefin resin layer 21 may contain polypropylene that has been mechanically or chemically recycled.

The thickness of the polyolefin resin layer 21 is, for example, 20 μm or more, and may be 40 μm or more. The thickness of the polyolefin resin layer 21 is, for example, 100 μm or less, and may be 80 μm or less.

As shown in FIG. 2, the polyolefin resin layer 21 may include a first copolymer layer 21a, a homopolymer layer 21b, and a second copolymer layer 21c. The first copolymer layer 21a and the second copolymer layer 21c contain the above-mentioned polypropylene copolymer. The homopolymer layer 21b contains the above-mentioned polypropylene homopolymer. By including the first copolymer layer 21a in the polyolefin resin layer 21, the sealing property of the sealant film 20 can be enhanced. Since the polyolefin resin layer 21 contains the homopolymer layer 21b, it is possible to suppress the occurrence of defects such as pinholes and breaks in the barrier film 10 due to the flow of polypropylene during heating. By including the second copolymer layer 21c in the polyolefin resin layer 21, the adhesion between the polyolefin resin layer 21 and the adhesive resin layer 22 can be enhanced.

The thickness of the first copolymer layer 21a is, for example, 5 μm or more, and may be 10 μm or more. The thickness of the first copolymer layer 21a is, for example, 20 μm or less, and may be 17 μm or less.

The thickness of the homopolymer layer 21b is, for example, 10 μm or more, and may be 15 μm or more. The thickness of the homopolymer layer 21b is, for example, 50 μm or less, and may be 30 μm or less. The thickness of the homopolymer layer 21b may be larger than the thickness of the first copolymer layer 21a.

The thickness of the second copolymer layer 21c is, for example, 2 μm or more, and may be 3 μm or more. The thickness of the second copolymer layer 21c is, for example, 20 μm or less, may be 15 μm or less, or may be 10 μm or less. The thickness of the second copolymer layer 21c may be smaller than the thickness of the first copolymer layer 21a and the thickness of the homopolymer layer 21b.

When the polyolefin resin layer 21 is a polypropylene resin layer, the content of polypropylene in the polyolefin resin layer 21 is, for example, 70% by mass or more, 80% by mass or more, or 90% by mass or more. ..

The polypropylene resin layer may contain a resin material other than polypropylene. For example, the polypropylene resin layer may contain a polyolefin such as polyethylene, a (meth) acrylic resin, a vinyl resin, a cellulose resin, a polyamide resin, a polyester, an ionomer resin, and the like.

(Surface resin layer)
The surface resin layer 23 contains a resin material having a polar group. Therefore, the thin-film deposition layer 30 tends to adhere to the surface of the surface resin layer 23. Thereby, the barrier property of the barrier film 10 can be enhanced.

The polar group means a group containing one or more heteroatoms. The polar group is, for example, an ester group, an epoxy group, a hydroxyl group, an amino group, an amide group, a carboxyl group, a carbonyl group, a carboxylic acid anhydride group, a sulfone group, a thiol group and a halogen group. Preferably, the polar group is a hydroxyl group, an ester group, an amino group, an amide group, a carboxyl group or a carbonyl group, and particularly preferably a hydroxyl group.

The resin material of the surface resin layer 23 is, for example, ethylene vinyl alcohol copolymer, polyvinyl alcohol, polyamide resin and the like. The polyamide resin is nylon 6, nylon 6, 6, MXD nylon, amorphous nylon and the like. The resin material of the surface resin layer 23 is preferably ethylene vinyl alcohol copolymer or polyvinyl alcohol.

The surface resin layer 23 may contain an additive as long as the adhesion of the vapor-filmed layer 30 to the surface resin layer 23 is not impaired. Additives include, for example, cross-linking agents, antioxidants, anti-blocking agents, lubricants (slip agents), UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments and modifying resins. ..

The ratio of the thickness of the surface resin layer 23 to the thickness of the sealant film 20 is, for example, 1% or more, may be 3% or more, or may be 5% or more. This makes it possible to improve the adhesion of the thin-film deposition layer 30 to the surface resin layer 23. Therefore, the barrier property of the barrier film 10 can be enhanced. In addition, the laminating strength of the laminated body provided with the barrier film 10 can be increased.

The ratio of the thickness of the surface resin layer 23 to the thickness of the sealant film 20 is, for example, 20% or less, may be 15% or less, or may be 10% or less. This makes it possible to improve the film-forming property and processability of the sealant film 20. Further, the recyclability of the barrier film 10 and the recyclability of the laminate provided with the barrier film 10 can be enhanced.

The thickness of the surface resin layer 23 is, for example, 1 μm or more, may be 2 μm or more, or may be 3 μm or more. The thickness of the surface resin layer 23 is, for example, 5 μm or less, and may be 4 μm or less.

[Adhesive resin layer]
The adhesive resin layer 22 contains a resin that adheres the polyolefin resin layer 21 and the surface resin layer 23. By providing the adhesive resin layer 22, the adhesion between the polyolefin resin layer 21 and the surface resin layer 23 can be enhanced.

The adhesive resin layer 22 may contain adhesive resins such as polyether, polyester, silicone resin, epoxy resin, polyurethane, vinyl resin, phenol resin and polyolefin. Preferably, the adhesive resin layer 22 contains a polyolefin and an acid-modified product thereof. When the polyolefin resin layer 21 is a polypropylene resin layer, the adhesive resin layer 22 preferably contains polypropylene and an acid-modified product thereof. Thereby, the composition ratio of polypropylene in the barrier film 10 can be increased. Therefore, the recyclability of the barrier film 10 and the laminate and the packaging container described later can be improved.
The adhesive resin layer 22 may contain commercially available polypropylene and an acid-modified product thereof. For example, the adhesive resin layer 22 may contain an Admer series manufactured by Mitsui Chemicals, Inc.

The thickness of the adhesive resin layer 22 is, for example, 1 μm or more, may be 2 μm or more, or may be 3 μm or more. Thereby, the adhesion between the polyolefin resin layer 21 and the surface resin layer 23 can be further improved. The thickness of the adhesive resin layer 22 is, for example, 15 μm or less, may be 10 μm or less, or may be 5 μm or less. Thereby, the processability of the sealant film 20 can be further improved.

[Embedded layer]
The thin-film deposition layer 30 includes a metal layer or an inorganic oxide layer. The thin-film deposition layer 30 is difficult for gases such as oxygen and water vapor to pass through. Therefore, the barrier film 10 and the laminate described later can have barrier properties such as oxygen barrier properties and water vapor barrier properties. As a result, it is possible to suppress a decrease in the mass of the contents in the packaging container made of the laminated body. In addition, it is possible to prevent light from passing through the laminate and reaching the contents. As a result, it is possible to suppress the oxidation of the components of the contents such as oil.

The metal layer may contain a metal such as aluminum. For example, the metal layer may include a layer of aluminum vapor-deposited on the surface resin layer 23.

The inorganic oxide layer may be, for example, aluminum oxide (alumina), silicon oxide (silica), magsium oxide, calcium oxide, zirconium oxide, titanium oxide, boron oxide, hafnium oxide, barium oxide, silicon oxide (carbon-containing silicon oxide). It may contain an inorganic oxide such as. Preferably, the inorganic oxide layer comprises silica, silicon carbide oxide or alumina. Silica is preferable in that it does not require an aging treatment after forming the vapor-filmed layer.

The thickness of the thin-film deposition layer 30 is, for example, 1 nm or more, may be 5 nm or more, or may be 10 nm or more. Thereby, the barrier property of the barrier film 10 can be further enhanced. The thickness of the thin-film deposition layer 30 may be 150 nm or less, 100 nm or less, or 50 nm or less. As a result, it is possible to prevent defects such as cracks from occurring in the thin-film deposition layer 30. In addition, the recycling characteristics of the laminate and the packaging container can be enhanced.

The thin-film deposition layer 30 may be composed of a single layer or may include a plurality of layers. The single layer is a layer formed by one vapor deposition step. The plurality of layers are formed by a plurality of vapor deposition steps. The materials constituting the plurality of layers may be the same or different. The methods for forming the plurality of layers may be the same or different.

(Manufacturing method of barrier film)
Next, a method for manufacturing the barrier film 10 will be described.

First, the sealant film 20 is produced by a coextrusion method. Specifically, the polyolefin constituting the polyolefin resin layer 21, the adhesive resin constituting the adhesive resin layer 22, and the resin material constituting the surface resin layer 23 are used by the T-die method, the inflation method, or the like. Push out together. As a result, the sealant film 20 can be produced. As shown in FIG. 2, when the polyolefin resin layer 21 includes the first copolymer layer 21a, the homopolymer layer 21b, and the second copolymer layer 21c, the material of each polymer layer is the adhesive resin constituting the adhesive resin layer 22 and the adhesive resin. It is extruded together with the resin material constituting the surface resin layer 23.

Subsequently, the vapor deposition layer 30 is formed on the surface resin layer 23 of the sealant film 20 by a vapor deposition method. Thereby, the barrier film 10 including the sealant film 20 and the vapor deposition layer 30 can be obtained.

As a method for forming the thin-film deposition layer 30, a known method can be used. For example, physical vapor deposition methods (PVD methods) such as vacuum vapor deposition, sputtering and ion plating, and plasma chemical vapor deposition, thermochemical vapor deposition and photochemical vapor deposition. Chemical vapor deposition method (CVD method, CVD method) and the like can be used.

The surface resin layer 23 may be surface-treated. This makes it possible to improve the adhesion with the thin-film deposition layer 30. The surface treatment method is not particularly limited, for example, corona discharge treatment, ozone treatment, low temperature plasma treatment using oxygen gas and / or nitrogen gas, physical treatment such as glow discharge treatment, and oxidation using chemicals. Examples include chemical treatment such as treatment.

When the vapor deposition layer 30 is formed by the PVD method, a vacuum film forming apparatus having a plasma assist function may be used as described below. For example, as shown in FIGS. 3 and 4, the vacuum film forming apparatus includes a vacuum container 101, an unwinding section 102, a film forming drum 103, a winding section 104, a transport roll 105, an evaporation source 106, and a deposition box 108. The vapor deposition material 109 and the plasma gun 110 may be provided. When the vapor deposition layer 30 contains an inorganic oxide, the vacuum film forming apparatus may include a reaction gas supply unit 107. FIG. 3 is a schematic cross-sectional view of the vacuum film forming apparatus in the XZ plane direction. FIG. 4 is a schematic cross-sectional view of the vacuum film forming apparatus in the XY plane direction.

As shown in FIG. 3, the sealant film 20 wound around the film forming drum 103 is arranged so that the surface resin layer 23 faces downward. Below the film forming drum 103, an electrically grounded protective box 108 is arranged. The evaporation source 106 is arranged on the bottom surface of the protective box 108. The film forming drum 103 is arranged at a position facing the upper surface of the evaporation source 106 in the vertical direction at a certain interval. The transport roll 105 is arranged between the unwinding unit 102 and the film forming drum 103, and between the film forming drum 103 and the winding unit 104. Although not shown, the vacuum vessel 101 is connected to a vacuum pump.

The evaporation source 106 holds the vapor deposition material 109. Although not shown, the evaporation source 106 includes a heating device. The reaction gas supply unit 107 supplies a reaction gas that reacts with the evaporated vaporized material 109. The reaction gas is oxygen, nitrogen, helium, argon or a mixed gas thereof. When the vapor deposition layer 30 contains an inorganic oxide, the reaction gas supply unit 107 supplies oxygen.

The vapor-deposited material 109 evaporated from the evaporation source 106 heads toward the surface resin layer 23 of the sealant film 20. Plasma is irradiated from the plasma gun 110 toward the surface resin layer 23. As a result, the vapor deposition layer 30 is formed. Details of such a forming method are disclosed in, for example, Japanese Patent Application Laid-Open No. 2011-214089.

Next, an example of forming the thin-film deposition layer 30 of the inorganic oxide by the plasma chemical vapor deposition method will be described. As the plasma generator, a generator such as high frequency plasma, pulse wave plasma, or microwave plasma can be used. Further, an apparatus having two or more film forming chambers may be used. The device is preferably equipped with a vacuum pump. As a result, each film forming chamber can be held in a vacuum. The degree of vacuum in each film forming chamber is preferably 1 × 10 Pa to 1 × 10 ^-6 Pa. An example of the film forming method of the vapor deposition layer 30 using the plasma generator is described below.

First, the sealant film 20 is sent out to the film forming chamber. Subsequently, the sealant film 20 is conveyed onto the drum at a predetermined speed. Subsequently, the gas supply device supplies a mixed gas composition containing a film-forming monomer gas containing an inorganic oxide, an oxygen gas, an inert gas, and the like to the film forming chamber. The surface resin layer 23 is irradiated with plasma generated by glow discharge to form a thin-film deposition layer 30 on the surface resin layer 23. Details of such a forming method are disclosed in, for example, Japanese Patent Application Laid-Open No. 2012-076292.

As an apparatus used for the method for forming a vapor-deposited film, a continuous vapor-deposited film film-forming apparatus including a plasma pretreatment chamber and a film-forming chamber may be used as described below.
First, in the plasma pretreatment chamber, plasma is irradiated to the surface resin layer 23 of the sealant film 20 from the plasma supply nozzle. Subsequently, the thin-film deposition layer 30 is formed on the surface resin layer 23 in the film-forming chamber. Details of such a forming method are disclosed, for example, in the pamphlet of International Publication WO2019 / 0879960.

The above-mentioned surface treatment may be applied to the surface of the thin-film deposition layer 30.

(Effect of sealant film)
In this embodiment, the sealant film 20 includes a surface resin layer 23 containing a resin material having a polar group. Therefore, by forming the thin-film deposition layer 30 on the surface resin layer 23, the adhesion between the sealant film 20 and the thin-film deposition layer 30 can be improved. Thereby, the barrier property of the barrier film 10 can be enhanced. Further, when the thin-film vapor deposition layer 30 contains a metal layer made of aluminum or the like, the light-shielding property of the barrier film 10 can be enhanced.

In the present embodiment, the sealant film 20 includes the first copolymer layer 21a, so that the impact resistance of the sealant film 20 can be enhanced. The breaking energy of the sealant film 20 is, for example, 0.1 J or more, 0.2 J or more, or 0.3 J or more. The value obtained by dividing the breaking energy of the sealant film 20 by the thickness of the sealant film 20 is, for example, 0.0025 J / μm or more, 0.0050 J / μm or more, or 0.0075 J / μm or more. good. These values also hold for the barrier film 10 provided with the sealant film 20 and the vapor deposition layer 30.

As a measuring instrument for measuring the breaking energy of the sealant film 20, a film impact tester manufactured by Toyo Seiki Seisakusho Co., Ltd. is used. Specifically, the hammer of the film impact tester applies an impact to the test piece of the sealant film 20 in a tensioned state. Measure the strength when the test piece breaks. As the hammer, a 3J hammer is used. The diameter of the impact ball at the tip of the hammer is 12.7 mm. The lifting angle of the hammer is 90 °. The specimen comprises an effective dimensional area consisting of a circle with a diameter of 35 mm. For example, the shape of the test piece is a square with a piece of 100 mm. In the measurement, while the test piece is held by the chuck, an impact is applied to the effective dimensional area of the test piece with a hammer.

The breaking energy of the sealant film 20 is measured for 5 test pieces. The average of the breaking energies of the five test pieces is adopted as the breaking energy of the sealant film 20. The environment at the time of measurement is a temperature of 23 ° C. and a relative humidity of 50% RH.

The oxygen permeability of the barrier film 10 is, for example, 0.50 cc / m ² · day · atm or less, may be 0.40 cc / m ² · day · atm or less, and 0.30 cc / m ² · day ·. It may be less than or equal to atm. Oxygen permeability is measured in an environment with a temperature of 23 ° C. and a relative humidity of 90% RH according to JIS K 7126. As the oxygen permeability measuring device, an oxygen permeability measuring device OX-TRAN2 / 20 manufactured by MOCON is used.

The water vapor transmission rate of the barrier film 10 is, for example, 2.0 g / m ² · day or less, 1.0 g / m ² · day or less, or 0.50 g / m ² · day or less. .. The water vapor transmission rate is measured in an environment of a temperature of 40 ° C. and a relative humidity of 90% RH in accordance with JIS K 7129. As the water vapor transmission rate measuring device, a water vapor transmission rate measuring device PERMATRAN-w 3/33 manufactured by MOCON is used.

The total light transmittance of the barrier film 10 is, for example, 1.0% or less, 0.50% or less, or 0.20% or less. The total light transmittance is measured in an environment of a temperature of 23 ° C. and a relative humidity of 90% RH in accordance with JIS K 7361. As a measuring instrument for the total light transmittance, a haze meter MDH4000 manufactured by Nippon Denshoku Industries Co., Ltd. is used.

Further, in the present embodiment, the polyolefin resin layer 21 includes a first copolymer layer 21a, a homopolymer layer 21b, and a second copolymer layer 21c. By including the first copolymer layer 21a in the polyolefin resin layer 21, the sealing property and impact resistance of the sealant film 20 can be enhanced. Since the polyolefin resin layer 21 contains the homopolymer layer 21b, it is possible to suppress the occurrence of defects such as pinholes and breaks in the barrier film 10 due to the flow of polypropylene during heating. Further, since the heat resistant temperature of the homopolymer layer 21b is high, the homopolymer layer 21b has high rigidity. Therefore, the resistance of the barrier film 10 to bending fatigue can be increased. By including the second copolymer layer 21c in the polyolefin resin layer 21, the adhesion between the polyolefin resin layer 21 and the adhesive resin layer 22 can be enhanced.

The thickness of the barrier film 10 is, for example, 20 μm or more, and may be 40 μm or more. The thickness of the barrier film 10 is, for example, 80 μm or less, and may be 60 μm or less.

(Laminated body)
Next, the laminated body provided with the barrier film 10 will be described. The laminate may be used as a packaging material constituting a packaging container.

FIG. 5 is a cross-sectional view showing an example of the laminated body 50 according to the present embodiment. The laminate 50 includes a base material 40 and a sealant film 20. The laminated body 50 includes an inner surface 50x and an outer surface 50y. The inner surface 50x is composed of the polyolefin resin layer 21 of the sealant film 20. The outer surface 50y may be composed of the base material 40.

〔Base material〕
The base material 40 faces the second surface 20y of the sealant film 20. The sealant film 20 and the base material 40 may be laminated by, for example, a dry laminating method. In this case, the adhesive layer 45 is located between the base material 40 and the sealant film 20.

The base material 40 may include a plastic film. For example, the base material 40 is a polyolefin film such as a polyethylene film or a polypropylene film, a polyester film such as a polyethylene terephthalate film or a polybutylene terephthalate, a nylon film or a polyamide film such as a nylon 6 / metaxylylene diamine nylon 6 co-pressed co-stretched film. May include. The base material 40 may contain only one plastic film, or may contain two or more plastic films.

Preferably, the substrate 40 contains a polyolefin film. When the polyolefin resin layer 21 of the sealant film 20 is a polypropylene resin layer, the base material 40 preferably contains a polypropylene film. This makes it possible to increase the composition ratio of polypropylene in the laminated body 50. Therefore, the recycling suitability of the laminated body 50 and the packaging container can be improved.

The plastic film may be stretched in a predetermined direction. In the following description, the stretched plastic film is also referred to as a stretched plastic film. The plastic film may be a uniaxially stretched film stretched in a predetermined unidirectional direction, or may be a biaxially stretched film stretched in a predetermined bidirectional direction. The draw ratio may be 2 times or more, or 5 times or more. The draw ratio may be 15 times or less, or 13 times or less.

The thickness of the stretched plastic film is, for example, 10 μm or more, and may be 15 μm or more. This makes it possible to increase the strength and heat resistance of the laminated body 50. The thickness of the stretched plastic film is, for example, 50 μm or less, and may be 40 μm or less. This makes it possible to improve the film forming property and processability of the base material 40.

When the base material 40 includes a plastic film, as shown in FIG. 6, the laminate 50 may include a printing layer 41 located between the base material 40 and the adhesive layer 45. The printing layer 41 is a layer for showing product information and giving an aesthetic impression to the packaging container. The print layer 41 represents characters, numbers, symbols, figures, patterns, and the like. As the material constituting the print layer 41, an ink for gravure printing or an ink for flexographic printing can be used. As a specific example of the ink for gravure printing, a finale manufactured by DIC Graphics Co., Ltd. can be mentioned.

When the thin-film deposition layer 30 includes a metal layer made of aluminum or the like, if the thin-film deposition layer 30 is formed on the base material 40, the print layer 41 becomes invisible. In the present embodiment, since the vapor deposition layer 30 is formed on the sealant film 20, the print layer 41 can be visually recognized from the outer surface 50y side of the laminate 50.

The base material 40 may contain paper. The basis weight of the paper is, for example, 20 g / m ² or more, 40 g / m ² or more, or 50 g / m ² or more. The basis weight of the paper is, for example, 150 g / m ² or less, 100 g / m ² or less, or 80 g / m ² or less. As the paper, kraft paper, art paper, coated paper, glassin paper, pure white roll paper, bleached kraft paper, high-quality paper and the like can be used.

The adhesion of the thin-film deposition layer 30 to the paper is low. Therefore, when the thin-film deposition layer 30 is formed on paper, the laminating strength of the laminated body 50 is low. According to this embodiment, the vapor deposition layer 30 is formed on the sealant film 20. Therefore, even when the laminated body 50 includes the paper and the thin-film deposition layer 30, the laminating strength of the laminated body 50 can be increased.

[Adhesive layer]
The adhesive layer 45 is a layer for adhering the base material 40 and the sealant film 20 by a dry laminating method. The adhesive layer 45 is formed by applying an adhesive to the surface of the base material 40 or the base material 40 and drying it. Examples of the adhesive constituting the adhesive layer 45 include one-component or two-component curable or non-curable vinyl-based, (meth) acrylic-based, polyamide-based, polyester-based, polyether-based, and polyurethane-based adhesives. Epoxy-based, rubber-based, and other solvent-based, water-based, or emulsion-based adhesives can be used. As the two-component curable adhesive, a cured product of a polyol and an isocyanate compound can be used. For example, the two-component curable adhesive may contain a cured product of a polyester polyol and an isocyanate compound. For example, the two-component curable adhesive may contain an oxygen barrier adhesive PASLIM manufactured by DIC Corporation. Oxygen barrier adhesive Paslim contains polyester polyols, isocyanate compounds, and phosphate-modified compounds. The oxygen barrier adhesive passrim is, for example, PASLIM VM001 / VM102CP. PASLIM VM001 / VM102CP contains a polyester-based main skeleton and a curing agent having two or more isocyanate groups. As a coating method of the adhesive, for example, a direct gravure roll coating method, a gravure roll coating method, a kiss coating method, a reverse roll coating method, a fonten method, a transfer roll coating method, or other methods can be applied.

The thickness of the adhesive layer 45 is, for example, 1 μm or more, and may be 2 μm or more. The thickness of the adhesive layer 45 is, for example, 5 μm or less, and may be 4 μm or less.

(Effect of laminated body)
In this embodiment, the sealant film 20 includes a surface resin layer 23 containing a resin material having a polar group. Therefore, by forming the thin-film deposition layer 30 on the surface resin layer 23, the adhesion between the sealant film 20 and the thin-film deposition layer 30 can be improved. Thereby, the laminating strength of the laminated body 50 can be increased.

The laminate strength of the laminate 50 is, for example, 0.5 N / 15 mm or more, 1.5 N / 15 mm or more, 2.0 N / 15 mm or more, 2.5 N / 15 mm or more. You may. The laminate strength of the laminate 50 is, for example, 5.0 N / 15 mm or less, and may be 4.0 N / 15 mm or less. Laminate strength is measured in an environment with a temperature of 23 ° C. and a relative humidity of 90% RH in accordance with JIS K 6854-2. As the laminating strength measuring instrument, A & D's Tensilon universal material tester RTC-1310 is used.

A method for measuring the laminate strength will be described with reference to FIGS. 7 to 9. First, the laminated body 50 was cut out to prepare a rectangular test piece including a long side and a short side. The length of the short side is 15 mm. Subsequently, as shown in FIG. 7, the sealant film 20 and the base material 40 are peeled off over 15 mm in the long side direction. Subsequently, as shown in FIG. 8, the portion of the test piece that has been peeled off is gripped by the gripping tool 56 and the gripping tool 57, respectively. Subsequently, the gripping tools 56 and 57 are pulled in the directions orthogonal to the plane direction of the test piece, respectively, in opposite directions at a speed of 50 mm / min. The tensile stress applied to the grips 56 and 57 is measured. The distance S between the gripping tools 56 and 57 at the start of pulling is 30 mm. The distance S between the gripping tools 56 and 57 at the end of pulling is 60 mm.

FIG. 9 is a diagram showing an example of a measurement result of tensile stress. In FIG. 9, the horizontal axis represents the distance S between the grips 56 and 57, and the vertical axis represents the tensile stress F applied to the grips 56 and 57. The change of the tensile stress F with respect to the interval S goes through the first region R1 and enters the second region R2 in which the rate of change of the tensile stress is smaller than that of the first region R1. The second region R2 is also referred to as a stable region.

The tensile stress F in the second region R2 is measured for the five test pieces. Subsequently, the average value of the tensile stress F in the second region R2 is calculated for each of the five test pieces. The average of the five average values is adopted as the laminate strength of the laminate 50. The environment at the time of measurement is a temperature of 23 ° C. and a relative humidity of 50% RH.

In the present embodiment, the barrier property of the laminated body 50 can be enhanced by providing the laminated body 50 with the barrier film 10. Further, when the thin-film deposition layer 30 includes a metal layer made of aluminum or the like, the light-shielding property of the laminated body 50 can be enhanced.

The oxygen permeability of the laminate 50 is, for example, 0.50 cc / m ² · day · atm or less, may be 0.40 cc / m ² · day · atm or less, and 0.30 cc / m ² · day ·. It may be less than or equal to atm. The oxygen permeability is measured in an environment of a temperature of 23 ° C. and a relative humidity of 90% RH in accordance with JIS K 7126, as in the case of the sealant film 20.

The water vapor transmission rate of the laminated body 50 is, for example, 2.0 g / m ² · day or less, may be 1.0 g / m ² · day or less, or 0.50 g / m ² · day or less. good. The water vapor transmission rate is measured in an environment of a temperature of 40 ° C. and a relative humidity of 90% RH in accordance with JIS K 7129, as in the case of the sealant film 20.

The total light transmittance of the laminated body 50 is, for example, 1.0% or less, 0.50% or less, or 0.20% or less. The total light transmittance is measured in an environment of a temperature of 23 ° C. and a relative humidity of 90% RH in accordance with JIS K 7361, as in the case of the sealant film 20.

The thickness of the laminated body 50 is, for example, 20 μm or more, 30 μm or more, or 50 μm or more. The thickness of the laminate 50 is, for example, 100 μm or less, 90 μm or less, or 80 μm or less.

(Packaging container)
The packaging container of the present invention includes the above-mentioned laminate 50. When the base material 40 contains a plastic film, the packaging container is, for example, a pouch, a lid material, a laminated tube, or the like. When the base material 40 contains paper, the packaging container is, for example, a paper container.

Examples of the packaging bag include a standing pouch type, a side seal type, a two-way seal type, a three-way seal type, a four-way seal type, an envelope-attached seal type, a gassho-attached seal type (pillow-seal type), a fold-attached seal type, and a flat-bottomed seal. Examples include various types of packaging bags such as a mold, a square bottom seal type, and a gusset type.

A standing pouch will be described as an example of a pouch. FIG. 10 is a diagram briefly showing an example of the configuration of the standing pouch. The packaging container 60 includes a body portion (side sheet) 61 and a bottom portion (bottom sheet) 62. The side sheet 61 and the bottom sheet 62 of the packaging container 60 may be made of the same member or may be made of different members. For example, both the side sheet 61 and the bottom sheet 62 may be the above-mentioned laminated body 50. Alternatively, either one of the side sheet 61 and the bottom sheet 62 may be the above-mentioned laminated body 50.

FIG. 11 is a diagram showing another example of the pouch. In the pouch manufacturing process of FIG. 11, two laminated bodies 50 are prepared, and these are laminated so that the polyolefin resin layers 21 face each other. Subsequently, the other two laminated bodies folded in a V shape are inserted between the two laminated bodies 50 at one side end and the other side end of the two laminated bodies 50. At this time, the sealant layer of the other two laminated bodies faces outward. Subsequently, 0x sealing is performed along one side end, the other side end, and the lower end of the two laminated bodies 50. This allows the side set pouch as shown in FIG. 11 to be made.

FIG. 12 is a diagram showing another example of the pouch. As shown in FIG. 12, the packaging container 60 may be a pouch having no gusset portion.

As a heat sealing method, for example, a known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, or an ultrasonic seal can be adopted.

The contents to be filled in the packaging container are not particularly limited. The contents may be liquids, powders and gels. The contents may be food or non-food.

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

(Example 1)
A sealant film 20 including a surface resin layer 23, a tangible resin layer 22, a second copolymer layer 21c, a homopolymer layer 21b and a first copolymer layer 21a was produced by a coextrusion method. As the surface resin layer 23, Nylon 6 Ultramid (registered trademark) B36LN manufactured by BASF was used. As the adhesive resin layer 22, maleic anhydride-modified polypropylene QF551 manufactured by Mitsui Chemicals was used. As the second copolymer layer 21c, a polypropylene random copolymer PC630A manufactured by SunAllomer was used. As the homopolymer layer 21b, polypropylene homopolymer PC600A manufactured by SunAllomer was used. As the first copolymer layer 21a, a polypropylene random copolymer PC630A manufactured by SunAllomer was used. The thicknesses of the surface resin layer 23, the tangible resin layer 22, the second copolymer layer 21c, the homopolymer layer 21b and the first copolymer layer 21a were 3 μm, 4 μm, 3 μm, 17 μm and 13 μm, respectively. The surface resin layer 23 had a viscosity number of 218 ml / g (ISO307), a density of 1.15 g / cm ³ , and a melting point of 220 ° C. The MFR of the adhesive resin layer 22 was 5.7 g / 10 min (ASTM D1238), and the density was 0.890 g / cm ³ . The MFR and densities of the copolymer layers 21a and 21c were 7.5 g / 10 min and 0.9 g / cm ³ . The MFR and density of the homopolymer layer 21b were 7.5 g / 10 min and 0.9 g / cm ³ . The total thickness of the sealant film 20 was 40 μm. The ratio of the thickness of the surface resin layer 23 to the thickness of the sealant film 20 was 7.5%.

An aluminum vapor deposition layer 30 was formed on the surface resin layer 23 of the sealant film 20 by a wire-type vapor deposition method. As a result, the barrier film 10 provided with the sealant film 20 and the vapor deposition layer 30 was obtained. The thickness of the thin-film deposition layer 30 was 45 nm.

Subsequently, the base material 40 made of a plastic film and the sealant film 20 were bonded by a dry laminating method. As a result, the first laminated body 50 was obtained. As the plastic film, a biaxially stretched polypropylene film U1 manufactured by Mitsui Chemicals Tohcello was used. The thickness of the base material 40 was 20 μm. As the adhesive, PASLIM VM001 / VM108CP manufactured by DICG was used. The amount of the adhesive applied was 4 g / m ² .

Further, the base material 40 made of paper and the sealant film 20 were adhered by a dry laminating method. As a result, the second laminated body 50 was obtained. As the paper, kraft paper Tokai Craft C made by Tokushu Tokai Paper Co., Ltd. was used. The basis weight of the base material 40 was 50 g / m ² . As the adhesive, PASLIM VM001 / VM108CP manufactured by DICG was used. The amount of the adhesive applied was 4 g / m ² .

The layer structure of the first laminated body is expressed as follows.
OPP20 / DL / AL / Ny3 / Adhesive 4 / Random PP3 / Homo PP17 / Random PP13
The layer structure of the second laminated body is expressed as follows.
Paper / DL / AL / Ny3 / Adhesive 4 / Random PP3 / Homo PP17 / Random PP13
"/" Represents the boundary between layers. The leftmost layer is a layer constituting the outer surface 50y of the laminated body 50. The rightmost layer is a layer constituting the inner surface 50x of the laminated body 50.
"OPP" means biaxially stretched polypropylene film. "DL" means an adhesive layer. "AL" means a vapor-deposited layer of aluminum. "Ny" means nylon 6. "Adhesive" means an adhesive resin layer. "Random PP" means a random copolymer of polypropylene. "Homo PP" means a polypropylene homopolymer. The numbers mean the thickness of the layer. The unit of thickness is μm.

(Example 2)
As the surface resin layer 23, Kuraray's ethylene-vinyl alcohol copolymer E171B was used. The ratio of ethylene copolymerization in the surface resin layer 23 was 44 mol%. The MFR and density of the surface resin layer 23 were 1.7 g / 10 min and 1.14 g / cm ³ . Maleic anhydride-modified polypropylene AT3351 manufactured by Mitsui Chemicals was used as the adhesive resin layer 22. The MFR of the adhesive resin layer 22 was 11 g / 10 min (ASTM D1238), and the density was 0.890 g / cm ³ . The thicknesses of the surface resin layer 23 and the adhesive resin layer 22 were 3 μm and 4 μm, respectively. Except for these points, the first laminated body 50 and the second laminated body 50 were produced in the same manner as in the case of Example 1. The total thickness of the sealant film 20 was 40 μm. The ratio of the thickness of the surface resin layer 23 to the thickness of the sealant film 20 was 7.5%.

The layer structure of the first laminated body is expressed as follows.
OPP20 / DL / AL / EVOH3 / Adhesive 4 / Random PP3 / Homo PP17 / Random PP13
The layer structure of the second laminated body is expressed as follows.
Paper / DL / AL / EVOH3 / Adhesive 4 / Random PP3 / Homo PP17 / Random PP13
"EVOH" means an ethylene-vinyl alcohol copolymer.

(Comparative Example 1)
As the sealant film 20, an unstretched polypropylene film 2703 manufactured by Toray Film Processing was used. The unstretched polypropylene film 2703 includes an aluminum vapor deposition layer formed on the surface of the polypropylene resin layer. The thickness of the sealant film 20 was 40 μm. The thickness of the thin-film deposition layer was 45 nm. Except for these points, the first laminated body 50 and the second laminated body 50 were produced in the same manner as in the case of Example 1.

The layer structure of the first laminated body is expressed as follows.
OPP20 / DL / AL / CPP40
The layer structure of the second laminated body is expressed as follows.
Paper / DL / AL / CPP40
"CPP" means unstretched polypropylene film.

(Comparative Example 2)
The first laminated body 50 and the second laminated body 50 and the second laminated body are the same as in the case of Example 1 except that the thickness of the adhesive resin layer 22 is 1 μm and the thickness of the second copolymer layer 21c is 6 μm. Body 50 was made.

The layer structure of the first laminated body is expressed as follows.
OPP20 / DL / AL / Ny3 / Adhesive 1 / Random PP6 / Homo PP17 / Random PP13
The layer structure of the second laminated body is expressed as follows.
Paper / DL / AL / Ny3 / Adhesive 1 / Random PP6 / Homo PP17 / Random PP13

It has been difficult to stably form the first laminated body 50 and the second laminated body 50 having the above layer structure. When the polyolefin resin layer 21 contains a polyamide resin such as nylon, it is considered preferable that the thickness of the adhesive resin layer 22 is 2 μm or more in order to stably produce the barrier film 10 and the laminate 50.

(Comparative Example 3)
Similar to the case of Example 2, except that the thickness of the surface resin layer 23 is 2 μm, the thickness of the adhesive resin layer 22 is 2 μm, and the thickness of the second copolymer layer 21c is 6 μm. , The first laminated body 50 and the second laminated body 50 were produced.

The layer structure of the first laminated body is expressed as follows.
OPP20 / DL / AL / EVOH2 / Adhesive 2 / Random PP6 / Homo PP17 / Random PP13
The layer structure of the second laminated body is expressed as follows.
Paper / DL / AL / EVOH2 / Adhesive 2 / Random PP6 / Homo PP17 / Random PP13

In the first laminated body 50 and the second laminated body 50 having the above-mentioned layer structure, a white appearance was confirmed. When the surface resin layer 23 contains an ethylene-vinyl alcohol copolymer, it is considered preferable that the thickness of the surface resin layer 23 is 3 μm or more in order to prevent the appearance from becoming white. When the surface resin layer 23 contains an ethylene-vinyl alcohol copolymer, it is considered preferable that the thickness of the adhesive resin layer 22 is 3 μm or more in order to secure the laminating strength of the laminated body 50.

[Measurement of laminate strength]
The laminate strength of the first laminate 50 of Examples 1 and 2 and Comparative Example 1 was measured in an environment of a temperature of 23 ° C. and a relative humidity of 90% RH according to JIS K 6854-2. As a laminating strength measuring instrument, a Tensilon universal material tester RTC-1310 manufactured by A & D was used. Specifically, the laminate strength was measured by the method shown in FIGS. 7 to 9 described above.
The laminate strengths in Example 1, Example 2 and Comparative Example 1 were 3.0 N / 15 mm, 2.9 N / 15 mm and 0.5 N / 15 mm, respectively.
The measurement results represent the laminate strength between the layers with the lowest adhesion. In FIGS. 7 to 9, the test piece is peeled off between the adhesive layer 45 and the thin-film deposition layer 30, but the measurement result does not always represent the laminate strength between the adhesive layer 45 and the vapor-film deposition layer 30. ..

[Measurement of oxygen permeability]
The oxygen permeability of the first laminated body 50 of Examples 1 and 2 and Comparative Example 1 was measured in an environment of a temperature of 23 ° C. and a relative humidity of 90% RH according to JIS K 7126. As the oxygen permeability measuring device, an oxygen permeability measuring device OX-TRAN2 / 20 manufactured by MOCON was used. In the measurement, the sample of the first laminated body 50 was arranged so that the base material 40 was located on the oxygen supply side.
The oxygen permeability in Example 1, Example 2 and Comparative Example 1 is 0.20 cc / m ² · day · atm, 0.01 cc / m ² · day · atm and 4.0 cc / m ² · day · atm, respectively. Met.

[Measurement of water vapor transmission rate]
The water vapor transmission rate of the first laminated body 50 of Examples 1 and 2 and Comparative Example 1 was measured in an environment of a temperature of 40 ° C. and a relative humidity of 90% RH according to JIS K 7129. As the water vapor transmission rate measuring device, a water vapor transmission rate measuring device PERMATRAN-w 3/33 manufactured by MOCON was used. In the measurement, the sample of the first laminated body 50 was arranged so that the base material 40 was located on the steam supply side.
The water vapor transmission rates in Example 1, Example 2 and Comparative Example 1 were 0.10 g / m ² · day, 0.10 g / m ² · day and 0.5 g / m ² · day, respectively.

[Evaluation of heat shrinkage]
It was evaluated whether or not the first laminated body 50 of Examples 1 and 2 and Comparative Example 1 had shrinkage due to heat. Specifically, first, two first laminated bodies 50 were prepared. Subsequently, the two first laminated bodies 50 were laminated so that the polyolefin resin layer 21 was in contact with each other. Subsequently, the two first laminated bodies 50 were heat-sealed in a temperature range of 120 ° C. to 170 ° C. under the conditions of 1 kg and 1 second. It was visually confirmed whether or not heat shrinkage occurred in the first laminated body 50.
In the temperature range of 120 ° C. to 150 ° C., no thermal shrinkage occurred in either Examples 1 and 2 and Comparative Example 1.
At 160 ° C., some heat shrinkage occurred in Examples 1 and 2. In Comparative Example 1, a large heat shrinkage occurred as compared with the cases of Examples 1 and 2.
At 170 ° C., in Examples 1 and 2, larger heat shrinkage occurred than in the case of 160 ° C. in Examples 1 and 2. In Comparative Example 1, a large and remarkable heat shrinkage occurred as compared with the case of 170 ° C. in Examples 1 and 2.

[Measurement of optical density and total light transmittance]
The optical density and total light transmittance of the first laminated body 50 of Examples 1 and 2 and Comparative Example 1 were measured in an environment of a temperature of 23 ° C. and a relative humidity of 90% RH in accordance with JIS K 7361. As a measuring instrument for the total light transmittance, a haze meter MDH4000 manufactured by Nippon Denshoku Industries Co., Ltd. was used.
The optical densities in Example 1, Example 2, and Comparative Example 1 were 3.4, 3.0, and 2.0, respectively.
The total light transmittances in Example 1, Example 2 and Comparative Example 1 were 0.04%, 0.1% and 1.0%, respectively.

[Evaluation of surface gloss]
The surface gloss of the first laminated body 50 of Examples 1 and 2 and Comparative Example 1 was evaluated. Specifically, the first laminated body 50 was visually inspected from the base material 40 side, and it was confirmed whether or not the gloss of the aluminum vapor-deposited layer 30 appeared.
In Example 1, gloss appeared. In Example 2 and Comparative Example 1, the degree of gloss was smaller than that in Example 1.

[Evaluation of seal leak]
The seal leak of the second laminated body 50 of Examples 1 and 2 and Comparative Example 1 was evaluated. First, a pillow pouch was produced by heat-sealing the second laminated body 50. As the heat seal device, a vertical pillow filling machine TYTT type manufactured by Tokyo Automobile Machinery Works was used. The number of shots is 85 rpm, the sealing temperature of the vertical seal is 150 ° C, and the sealing temperature of the horizontal seal is 160 ° C. Subsequently, the inside of the pillow pouch was filled with the check liquid through the opening at the top of the pillow pouch. As the check liquid, an edgeless seal check liquid manufactured by Mitsubishi Gas Chemical Company was used. After filling the check solution, the pillow pouch was placed in an environment with a temperature of 23 ° C. and a relative humidity of 50% RH for 24 hours. After that, it was confirmed whether or not the check liquid leaked.
In Examples 1 and 2, no leak of the check liquid occurred. In Comparative Example 1, the check liquid leaked.

The measurement result and the evaluation result are shown in FIG. The laminated body 50 of Examples 1 and 2 shows better results than the laminated body 50 of Comparative Examples 1 and 3.

[Evaluation of breaking strength and breaking elongation]
The breaking strength and breaking elongation of the sealant film 20 of Example 1 and Comparative Example 1 were measured in an environment of a temperature of 23 ° C. and a relative humidity of 50% RH in accordance with JIS K7127. As a measuring instrument for breaking strength and breaking elongation, a Tensilon universal material tester RTC-1310 manufactured by A & D was used. In the measurement, a sealant film 20 cut into a rectangular film having a width of 10 mm and a length of 150 mm was used as a test piece. The distance at the start of measurement between the pair of chucks holding the test piece was 50 mm. The tensile speed of the test piece was 300 mm / min.
The breaking strengths of the sealant film 20 of Example 1 in the flow direction (MD) and the vertical direction (TD) were 46.1 MPa and 26.5 MPa. The breaking elongations of the sealant film 20 of Example 1 in the flow direction (MD) and the vertical direction (TD) were 372.8% and 403.8%.
The breaking strengths of the sealant film 20 of Comparative Example 1 in the flow direction (MD) and the vertical direction (TD) were 32.3 MPa and 28.3 MPa. The breaking elongations of the sealant film 20 of Comparative Example 1 in the flow direction (MD) and the vertical direction (TD) were 340.9% and 458.3%. The measurement results are shown in FIG.

[Measurement of breaking energy]
The breaking energies of the sealant films 20 of Example 1 and Comparative Example 1 were measured in an environment of a temperature of 23 ° C. and a relative humidity of 90% RH. A film impact tester manufactured by Toyo Seiki Seisakusho Co., Ltd. was used as a breaking energy measuring instrument.
The breaking energies of the sealant film 20 in Example 1 and Comparative Example 1 were 0.389J and 0.054J, respectively. The values obtained by dividing the breaking energy of the sealant film 20 by the thickness of the sealant film 20 were 0.00972 J / μm and 0.00135 J / μm in Example 1 and Comparative Example 1, respectively. The measurement results are shown in FIG.

10 Barrier film 20 Sealant film 20x First side 20y Second side 21 Polyolefin resin layer 21a First copolymer layer 21b Homopolymer layer 21c Second copolymer layer 22 Adhesive resin layer 23 Surface resin layer 30 Vapor deposition layer 40 Base material 41 Printing layer 45 Adhesive layer 50 Laminated body 50 x Inner surface 50y Outer surface 60 Packaging container

Claims (14)

A sealant film containing a first surface and a second surface located on the opposite side of the first surface, and
A thin-film deposition layer located on the second surface is provided.
The sealant film has a polyolefin resin layer constituting the first surface, a surface resin layer constituting the second surface and containing a resin material having a polar group, and between the polyolefin resin layer and the surface resin layer. A barrier film comprising an adhesive resin layer located. The barrier film according to claim 1, wherein the resin material is one or more resin materials selected from ethylene vinyl alcohol copolymer, polyvinyl alcohol, polyester, nylon 6, nylon 6,6, MXD nylon and amorphous nylon. .. The surface resin layer contains an ethylene vinyl alcohol copolymer and has a thickness of 3 μm or more.
The barrier film according to claim 2, wherein the adhesive resin layer has a thickness of 3 μm or more. The surface resin layer contains nylon 6, nylon 6, 6 or MXD nylon and has a thickness of 2 μm or more.
The barrier film according to claim 2, wherein the adhesive resin layer has a thickness of 2 μm or more. The barrier film according to any one of claims 1 to 4, wherein the ratio of the thickness of the surface resin layer to the thickness of the sealant film is 1% or more and 20% or less. The barrier film according to any one of claims 1 to 5, wherein the polyolefin resin layer is a polypropylene resin layer. The barrier film according to claim 6, wherein the polypropylene resin layer includes a first copolymer layer and a second copolymer layer, and a homopolymer layer located between the first copolymer layer and the second copolymer layer. The barrier film according to any one of claims 1 to 7, wherein the vapor-deposited layer includes a metal layer or an inorganic oxide layer. The barrier film according to any one of claims 1 to 8, wherein the value obtained by dividing the breaking energy of the sealant film by the thickness of the sealant film is 0.0025 J / μm or more. The barrier film according to any one of claims 1 to 9,
A laminate comprising a substrate. The substrate comprises a stretched plastic film
The laminate according to claim 10, further comprising a printing layer located between the substrate and the barrier film. The substrate comprises a stretched plastic film
The laminate according to claim 10 or 11, further comprising an adhesive layer located between the substrate and the barrier film. The laminate according to claim 10, wherein the base material contains paper. A packaging container comprising the laminate according to any one of claims 10 to 13.

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