JP2023023644A - Barrier laminate, lid material and package - Google Patents

Abstract

To reduce the amount of residual solvent in a laminate having a barrier substrate having a vapor-deposition film on a stretched polypropylene film, and a sealant layer.SOLUTION: A barrier laminate contains a substrate, an adhesive layer, and a sealant layer in a thickness direction in the stated order. The substrate is a barrier substrate having a polypropylene resin layer and a vapor-deposition film. The polypropylene resin layer is a stretched layer. The vapor-deposition film is composed of inorganic oxide. The adhesive layer is a layer of 2 μm or less in thickness. The amount of residual solvent in the barrier laminate is 10 mg/m2 or less.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present disclosure relates to barrier laminates, lid materials, and packaging containers.

A film made of polyester such as polyethylene terephthalate (hereinafter also referred to as "polyester film") is excellent in mechanical properties, chemical stability, heat resistance and transparency, and is inexpensive. Therefore, conventionally, polyester films have been used as base materials constituting laminates used to produce packaging containers.

Depending on the contents filled in the packaging container, the packaging container is required to have gas barrier properties such as oxygen barrier properties and water vapor barrier properties. In order to meet this demand, a deposited film containing alumina, silica, or the like is formed on the polyester film surface (see, for example, Patent Document 1). In recent years, substrates to replace polyester films have been sought. The use of polyolefin films, particularly polypropylene films, as the substrate has been investigated.

JP-A-2005-053223

The present inventors have considered using a stretched polypropylene film (hereinafter also referred to as "stretched polypropylene film") instead of a conventional polyester film. When producing a laminate comprising an oriented polypropylene film and a sealant film, an adhesive layer is usually provided between the two films. When producing the laminate, it is necessary to lower the drying temperature of the adhesive in order to prevent deterioration and heat shrinkage of the stretched polypropylene film compared to the laminate using the polyester film. In this case, the solvent in the adhesive may not be sufficiently removed by volatilization and may remain in the laminate, leaving an odor due to the residual solvent.

One of the problems to be solved by the present disclosure is to reduce the amount of residual solvent in a laminate having a barrier substrate in which a deposited film is formed on a stretched polypropylene film and a sealant layer.

The barrier laminate of the present disclosure includes a substrate, an adhesive layer, and a sealant layer in this order in the thickness direction. The substrate is a barrier substrate comprising a polypropylene resin layer and a deposited film. The polypropylene resin layer is a layer that has been stretched. The deposited film is composed of an inorganic oxide. The adhesive layer is a layer with a thickness of 2 μm or less. The residual solvent content in the barrier laminate is 10 mg/m ² or less.

According to the present disclosure, it is possible to reduce the amount of residual solvent in a laminate having a barrier substrate in which a deposited film is formed on a stretched polypropylene film, and a sealant layer.

FIG. 1 is a schematic cross-sectional view showing one embodiment of a barrier laminate. FIG. 2 is a schematic cross-sectional view showing one embodiment of the barrier laminate. FIG. 3 is a schematic cross-sectional view showing one embodiment of the barrier laminate. FIG. 4 is a schematic cross-sectional view showing one embodiment of the barrier laminate. FIG. 5 is a schematic cross-sectional view showing one embodiment of the barrier laminate. FIG. 6 is a schematic cross-sectional view showing one embodiment of the barrier laminate. FIG. 7 is a schematic cross-sectional view showing one embodiment of the barrier laminate. FIG. 8 is a schematic cross-sectional view showing one embodiment of the barrier laminate. FIG. 9 is a schematic cross-sectional view showing one embodiment of the barrier laminate. FIG. 10 is a schematic cross-sectional view showing one embodiment of a vapor deposition apparatus. FIG. 11 is a schematic cross-sectional view showing one embodiment of a vapor deposition apparatus. FIG. 12 is a schematic cross-sectional view showing another embodiment of the vapor deposition apparatus. FIG. 13 is a front view showing one embodiment of the packaging container. FIG. 14 is a perspective view showing one embodiment of the packaging container.

Hereinafter, embodiments of the present disclosure will be described in detail. This disclosure may be embodied in many different forms and should not be construed as limited to the description of the exemplary embodiments set forth below. In order to make the description clearer, the drawings may schematically represent the width, thickness, shape, etc. of each layer compared to the embodiment, but this is only an example and does not limit the interpretation of the present disclosure. . In this specification and each figure, elements similar to those already described with respect to previous figures may be denoted by the same reference numerals, and detailed description thereof may be omitted as appropriate.

In the following description, each component (e.g., polypropylene, α-olefin, resin material, additive, adhesive resin, inorganic oxide, and gas barrier resin) appearing may be used singly or in combination of two or more. may be used.

[Barrier laminate]
The barrier laminate of the present disclosure includes a substrate, an adhesive layer, and a sealant layer in this order in the thickness direction. The adhesive layer is a layer having a thickness of 2 μm or less. The substrate is a barrier substrate comprising a polypropylene resin layer and a deposited film.

The barrier laminate of the present disclosure may include a first substrate, a first adhesive layer, a second substrate, a second adhesive layer, and a sealant layer in this order in the thickness direction. preferable. Each of the first adhesive layer and the second adhesive layer is a layer having a thickness of 2 μm or less.
Either one of the first base material and the second base material is a barrier base material including a polypropylene resin layer and a deposited film. The other of the first base material and the second base material is a polypropylene resin base material that has been stretched. In this embodiment, a barrier substrate is used as one of the first substrate and the second substrate, and a polypropylene resin substrate is used as the other of the first substrate and the second substrate. However, in other embodiments, both the first substrate and the second substrate may be barrier substrates.

The polypropylene resin layer is stretched.
The deposited film is composed of an inorganic oxide.
The residual solvent amount in the barrier laminate of the present disclosure is 10 mg/m ² or less.

1 to 9 are schematic cross-sectional views showing one embodiment of the barrier laminate.
The barrier laminate 1 shown in FIG. 1 includes a barrier substrate 20 as a substrate, an adhesive layer 40, and a sealant layer 30 in this order in the thickness direction. The barrier base material 20 includes a polypropylene resin layer 22 and a deposited film 24 . In this example, the polypropylene resin layer 22 constitutes the outermost layer of the barrier laminate 1 and the deposited film 24 is in contact with the adhesive layer 40 .

FIG. 2 is the same as FIG. 1 except that the barrier substrate 20 has a surface coat layer or surface resin layer 23 between the polypropylene resin layer 22 and the deposited film 24 .

FIG. 3 is the same as FIG. 1 except that the barrier substrate 20 comprises a polypropylene resin layer 22, a surface coat layer or surface resin layer 23, a deposited film 24, and a barrier coat layer 25 in this order in the thickness direction. is similar to In this example, the barrier coat layer 25 is in contact with the adhesive layer 40 .

The barrier laminate 1 shown in FIG. 4 includes a polypropylene resin substrate 10 as a first substrate, an adhesive layer 40A, a barrier substrate 20 as a second substrate, an adhesive layer 40B, and a sealant. and layers 30 in this order in the thickness direction. The barrier base material 20 includes a polypropylene resin layer 22 and a deposited film 24 . In this example, the polypropylene resin layer 22 is in contact with the adhesive layer 40B, and the deposited film 24 is in contact with the adhesive layer 40A.

FIG. 5 is the same as FIG. 4 except that the barrier substrate 20 has a surface coating layer or surface resin layer 23 between the polypropylene resin layer 22 and the deposited film 24 .

FIG. 6 is the same as FIG. 4 except that the barrier substrate 20 comprises a polypropylene resin layer 22, a surface coat layer or surface resin layer 23, a deposited film 24, and a barrier coat layer 25 in this order in the thickness direction. is similar to In this example, the barrier coat layer 25 is in contact with the adhesive layer 40A.

The barrier laminate 1 shown in FIG. 7 includes a barrier substrate 20 as a first substrate, an adhesive layer 40A, a polypropylene resin substrate 10 as a second substrate, an adhesive layer 40B, and a sealant. and layers 30 in this order in the thickness direction. The barrier base material 20 includes a polypropylene resin layer 22 and a deposited film 24 . In this example, the polypropylene resin layer 22 constitutes the outermost layer of the barrier laminate 1, and the deposited film 24 is in contact with the adhesive layer 40A.

FIG. 8 is the same as FIG. 7 except that the barrier substrate 20 has a surface coat layer or surface resin layer 23 between the polypropylene resin layer 22 and the deposited film 24 .

FIG. 9 is the same as FIG. 7 except that the barrier substrate 20 comprises a polypropylene resin layer 22, a surface coat layer or surface resin layer 23, a deposited film 24, and a barrier coat layer 25 in this order in the thickness direction. is similar to In this example, the barrier coat layer 25 is in contact with the adhesive layer 40A.

The barrier laminate of the present disclosure, in one embodiment, comprises at least three elements: a polypropylene resin substrate, a barrier substrate and a sealant layer. Thereby, gas barrier properties (especially oxygen barrier properties and water vapor barrier properties) can be further improved.

When the first base material is a barrier base material, in one embodiment, the first base material is arranged so that the deposited film faces the sealant layer side and the polypropylene resin layer faces the side opposite to the sealant layer. are placed.
When the second base material is a barrier base material, in one embodiment, the second base material is arranged so that the deposited film faces the first base material side and the polypropylene resin layer faces the sealant layer side. Alternatively, the second substrate is arranged such that the deposited film faces the sealant layer side and the polypropylene resin layer faces the first substrate side. Among these, from the viewpoint that the deterioration of the vapor deposition film can be further suppressed, when the second base material is a barrier base material, the vapor deposition film faces the first base material side, and the polypropylene resin layer is the sealant layer. Preferably, the second substrate is arranged so as to face the side.

In one embodiment of the barrier laminate of the present disclosure, the first base material is a polypropylene resin base material, and the second base material is a barrier base material (see FIGS. 4 to 6). In this embodiment, the barrier laminate comprises a polypropylene resin substrate, a barrier substrate, and a sealant layer in this order in the thickness direction. The barrier layered product having such a structure appropriately protects the vapor-deposited film when subjected to heat treatment or the like, and further exhibits high gas barrier properties. In addition, the barrier laminate of the above embodiment has a smaller thermal shrinkage rate when subjected to heat treatment, and is therefore more excellent in bag-making aptitude.

In the present disclosure, the description “AAA composed of polypropylene” means that the main component of the AAA is polypropylene, but the AAA is not limited to a configuration consisting only of polypropylene. The AAA may contain components other than polypropylene. Specifically, the content of polypropylene in the AAA is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, and even more preferably 95% by mass or more.

<Barrier substrate>
The barrier laminate of the present disclosure includes a barrier substrate as a substrate.
The barrier substrate includes a polypropylene resin layer and a deposited film. The barrier substrate, in one embodiment, comprises a polypropylene resin layer and a deposited film provided on one surface of the resin layer. The barrier base material may have a surface coating layer or a surface resin layer between the polypropylene resin layer and the deposited film. The barrier substrate may have a barrier coat layer on the deposited film.

The barrier laminate of the present disclosure may include a first substrate, a first adhesive layer, a second substrate, a second adhesive layer, and a sealant layer in this order in the thickness direction. preferable. The barrier substrate constitutes the first substrate or the second substrate. When the polypropylene resin substrate is the first substrate, the barrier substrate is the second substrate. When the polypropylene resin substrate is the second substrate, the barrier substrate is the first substrate. In this embodiment, a barrier substrate is used as one of the first substrate and the second substrate, and a polypropylene resin substrate is used as the other of the first substrate and the second substrate. However, in other embodiments, both the first substrate and the second substrate may be barrier substrates.

(Polypropylene resin layer)
The polypropylene resin layer is made of polypropylene. By providing the barrier base material with a layer composed of polypropylene, for example, the oil resistance of packaging containers produced using the barrier base material can be improved.

Polypropylene may be homopolymer, random copolymer or block copolymer, or may be a mixture of two or more selected from these.

A propylene homopolymer is a polymer of propylene only. A propylene random copolymer is a random copolymer of propylene and an α-olefin other than propylene. A propylene block copolymer is a copolymer having a polymer block composed of propylene and a polymer block composed of an α-olefin other than propylene.

Examples of α-olefins include α-olefins having 2 to 20 carbon atoms, specifically ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1 -dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, 3-methyl-1-butene, 4-methyl-1-pentene and 6-methyl-1-heptene.

Among polypropylenes, homopolymers or random copolymers are preferably used from the viewpoint of transparency. When the rigidity and heat resistance of the packaging container are important, it is preferable to use a homopolymer. When the impact resistance of the packaging container is important, it is preferable to use a random copolymer.

In one embodiment, the melt flow rate (MFR) of polypropylene may be 0.1 g/10 min or more and 50 g/10 min or less, or 0.3 g/10 min or more and 30 g/10 min. minutes or less. The MFR of polypropylene is measured according to ASTM D1238 under conditions of a temperature of 230° C. and a load of 2.16 kg.

As the polypropylene, biomass-derived polypropylene, mechanically recycled or chemically recycled polypropylene may be used.

The content of polypropylene in the polypropylene resin layer is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, and even more preferably 95% by mass or more.

The polypropylene resin layer may contain resin materials other than polypropylene. Examples of resin materials include polyolefins such as polyethylene, (meth)acrylic resins, vinyl resins, cellulose resins, polyamides, polyesters, and ionomer resins.

The polypropylene resin layer may contain additives. Examples of additives include cross-linking agents, antioxidants, anti-blocking agents, slip agents, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments and modifying resins. be done.

The polypropylene resin layer is a layer that has been stretched. Thereby, for example, the heat resistance, impact resistance, water resistance and dimensional stability of the barrier laminate can be improved. A barrier laminate having such a resin layer is suitable, for example, as a packaging material constituting a packaging container subjected to boiling treatment or retorting treatment.
The stretching treatment may be uniaxial stretching or biaxial stretching.

The stretching ratio in the case of stretching in the longitudinal direction (flow direction of the base material, MD direction) is preferably 2 times or more and 15 times or less, more preferably 5 times or more and 13 times or less. The stretching ratio in the case of stretching in the transverse direction (direction perpendicular to the MD direction, TD direction) is preferably 2 to 15 times, more preferably 5 to 13 times. By setting the draw ratio to 2 times or more, the strength and heat resistance of the polypropylene resin layer can be further improved, and the printability of the polypropylene resin layer can be improved. From the viewpoint of breaking limit of the polypropylene resin layer, the draw ratio is preferably 15 times or less.

The polypropylene resin layer may be surface-treated in one embodiment. Thereby, for example, the adhesion between the polypropylene resin layer and other layers can be improved. Examples of surface treatment methods include physical treatments such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and/or nitrogen gas, glow discharge treatment; and oxidation treatment using chemicals. Chemical treatment can be mentioned.
An easy-adhesion layer may be provided on the surface of the polypropylene resin layer.

The polypropylene resin layer may have a single layer structure or a multilayer structure.
The thickness of the polypropylene resin layer is preferably 10 μm or more and 100 μm or less, more preferably 10 μm or more and 50 μm or less. When the thickness is at least the lower limit, for example, the strength and heat resistance of the barrier laminate can be further improved. When the thickness is equal to or less than the upper limit, for example, the processability of the barrier laminate can be further improved.

The barrier substrate may have a printed layer on the surface of the polypropylene resin layer. The image formed on the printed layer is not particularly limited, and may be letters, patterns, symbols, combinations thereof, or the like. The printing layer can also be formed using a biomass-derived ink. As a result, the environmental load can be further reduced.

Examples of methods for forming the printed layer include conventionally known printing methods such as gravure printing, offset printing, and flexographic printing. Among these, the flexographic printing method is preferable from the viewpoint of reducing the environmental load.

(Surface coat layer)
In one embodiment, the barrier substrate has a surface coat layer containing a resin material having a polar group between the polypropylene resin layer and the deposited film. By providing a surface coat layer containing a resin material having a polar group, it is possible to improve the adhesion of a deposited film formed on the surface coat layer, and also improve gas barrier properties.

In this embodiment, the barrier substrate comprises a resin substrate having a polypropylene resin layer and a surface coat layer, and a deposited film provided on the surface coat layer. This barrier base material has a polypropylene resin layer, a surface coat layer, and a deposited film in this order in the thickness direction.

A polar group refers to a group containing one or more heteroatoms, for example, an ester group, an epoxy group, a hydroxyl group, an amino group, an amide group, a urethane group, a carboxy group, a carbonyl group, a carboxylic acid anhydride group, a sulfo group, Thiol groups and halogen groups are included. Among these, from the viewpoint of laminating property of the packaging container, carboxy group, carbonyl group, ester group, hydroxyl group, amino group, amide group and urethane group are preferable, and carboxy group, hydroxyl group, amide group and urethane group are more preferable.

Examples of resin materials having polar groups include ethylene-vinyl alcohol copolymer (EVOH), polyvinyl alcohol (PVA), polyester, polyethyleneimine, hydroxyl group-containing (meth)acrylic resin, nylon 6, nylon 6,6, and MXD. Polyamides, such as nylon and amorphous nylon, and polyurethanes. Among these, ethylene-vinyl alcohol copolymer, polyvinyl alcohol, hydroxyl group-containing (meth)acrylic resin, polyamide and polyurethane are more preferable.

The surface coat layer can be formed using, for example, an aqueous emulsion or a solvent emulsion. Examples of water-based emulsions include polyamide-based emulsions, polyethylene-based emulsions, and polyurethane-based emulsions. Examples of solvent-based emulsions include (meth)acrylic resin-based emulsions and polyester-based emulsions.

The content of the resin material having a polar group in the surface coat layer is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more.
The surface coat layer may contain a resin material other than the resin material having a polar group.
The surface coat layer may contain the above additives.

The ratio of the thickness of the surface coat layer to the total thickness of the resin substrate is preferably 0.08% or more and 20% or less, more preferably 0.2% or more and 15% or less, and still more preferably 1% or more and 10% or less. , and more preferably 1% or more and 5% or less. When the above ratio is at least the lower limit, for example, the adhesion of the deposited film can be further improved, the gas barrier properties can be further improved, and the lamination strength of the packaging container can be further improved. When the above ratio is equal to or less than the upper limit, for example, the processability of the resin base material and the recyclability of the packaging container can be further improved.

The thickness of the surface coat layer is preferably 0.02 μm or more and 10 μm or less, more preferably 0.05 μm or more and 10 μm or less, still more preferably 0.1 μm or more and 10 μm or less, and even more preferably 0.2 μm or more and 5 μm or less. When the thickness is at least the lower limit, for example, the adhesion of the deposited film can be further improved, the gas barrier property can be further improved, and the lamination strength of the packaging container can be further improved. When the thickness is equal to or less than the upper limit, for example, the processing suitability of the resin base material and the recycling suitability of the packaging container can be further improved.

For example, a polypropylene or a resin composition containing polypropylene is formed into a film using a T-die method or an inflation method to obtain a resin film, then the resin film is stretched, and the resin film after stretching is surface-coated. A resin base material can be produced by applying and drying the layer-forming coating liquid.

(Surface resin layer)
In one embodiment, the barrier substrate comprises a surface resin layer containing a resin material having a melting point of 180° C. or higher (hereinafter also referred to as “high melting point resin material”) between the polypropylene resin layer and the deposited film. . By providing a surface resin layer containing a high-melting-point resin material, it is possible to improve the adhesion of the vapor-deposited film formed on the surface resin layer, and also improve the gas barrier properties.

In this embodiment, the barrier substrate comprises a resin substrate having a polypropylene resin layer and a surface resin layer, and a deposited film provided on the surface resin layer. This barrier base material has a polypropylene resin layer, a surface resin layer, and a deposited film in this order in the thickness direction.

The melting point of the high melting point resin material is preferably 185° C. or higher, more preferably 190° C. or higher, and even more preferably 205° C. or higher. When the melting point is at least the lower limit, for example, the adhesiveness of the deposited film can be further improved, the gas barrier property can be further improved, and the lamination strength of the packaging container can be further improved.

The melting point of the high melting point resin material is preferably 265° C. or lower, more preferably 260° C. or lower, and even more preferably 250° C. or lower. Thereby, for example, the film formability of the resin substrate can be improved.

As used herein, the melting point can be measured according to JIS K7121:2012 (method for measuring transition temperature of plastics). Specifically, using a differential scanning calorimeter (DSC) apparatus, the DSC curve can be measured at a heating rate of 10° C./min to determine the melting point.

The difference between the melting point of the high melting point resin material contained in the surface resin layer and the melting point of polypropylene contained in the polypropylene resin layer is preferably 20° C. or higher and 80° C. or lower, more preferably 20° C. or higher and 60° C. or lower. When the above difference is the lower limit, for example, the adhesion of the deposited film can be further improved, the gas barrier property can be further improved, and the lamination strength of the packaging container can be further improved. When the difference is equal to or less than the upper limit, for example, the film formability of the resin substrate can be further improved.

The high melting point resin material preferably has a polar group. A polar group refers to a group containing one or more heteroatoms, for example, an ester group, an epoxy group, a hydroxyl group, an amino group, an amide group, a urethane group, a carboxy group, a carbonyl group, a carboxylic acid anhydride group, a sulfo group, Thiol groups and halogen groups are included. Among these, hydroxyl group, ester group, amino group, amide group, carboxy group and carbonyl group are preferred, and amide group is more preferred, from the viewpoint of gas barrier properties and lamination strength of the packaging container.

The high melting point resin material may have a melting point of 180° C. or higher, and examples thereof include polyolefins, vinyl resins, (meth)acrylic resins, polyamides, polyimides, polyesters, cellulose resins, and ionomer resins. For example, a resin material having a melting point of 180° C. or higher and having a polar group is preferable, and ethylene-vinyl alcohol copolymer, polyvinyl alcohol, polyester, and polyamide such as nylon 6, nylon 6,6, MXD nylon and amorphous nylon. more preferred.

The content of the high melting point resin material in the surface resin layer is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

The surface resin layer may contain a resin material other than the high melting point resin material.
The surface resin layer may contain the above additives.
The surface resin layer may be subjected to the surface treatment described above.

The ratio of the thickness of the surface resin layer to the total thickness of the resin substrate is preferably 1% or more and 10% or less, more preferably 1% or more and 5% or less. When the above ratio is at least the lower limit, for example, the adhesion of the deposited film can be further improved, the gas barrier properties can be further improved, and the lamination strength of the packaging container can be further improved. When the above ratio is equal to or less than the upper limit, for example, the film formability and processability of the resin base material and the recyclability of the packaging container can be further improved.

The thickness of the surface resin layer is preferably 0.1 μm or more and 5 μm or less, more preferably 0.1 μm or more and 4 μm or less. When the thickness is at least the lower limit, for example, the adhesion of the deposited film can be further improved, the gas barrier property can be further improved, and the lamination strength of the packaging container can be further improved. When the thickness is equal to or less than the upper limit, for example, the film formability and processability of the resin substrate and the recyclability of the packaging container can be further improved.

In one embodiment, the resin base material can be provided with an adhesive resin layer between the polypropylene resin layer and the surface resin layer. Thereby, the adhesion between these layers can be improved.

The adhesive resin layer can be formed of, for example, an adhesive resin. Examples of adhesive resins include polyethers, polyesters, polyurethanes, silicone resins, epoxy resins, vinyl resins, phenol resins, polyolefins, and acid-modified polyolefins. Among these, polyolefin and its acid-modified products are preferred, and polypropylene and its acid-modified products are more preferred from the viewpoint of recyclability of packaging containers.

The thickness of the adhesive resin layer is, for example, 1 μm or more and 15 μm or less. When the thickness is 1 μm or more, for example, the adhesion between the polypropylene resin layer and the surface resin layer can be further improved. When the thickness is 15 μm or less, for example, the processability of the resin substrate can be further improved.

The resin substrate having a polypropylene resin layer, optionally an adhesive resin layer, and a surface resin layer is, in one embodiment, a coextruded stretched resin film. A co-extruded stretched resin film can be produced, for example, by forming a laminated film using a T-die method or an inflation method, and then stretching the laminated film. The laminate film may be stretched at the same time as the film is formed by the inflation method.

The stretching treatment may be uniaxial stretching or biaxial stretching.
The draw ratio for stretching in the MD direction is preferably 2 to 15 times, more preferably 5 to 13 times. The draw ratio in stretching in the TD direction is preferably 2 times or more and 15 times or less, more preferably 5 times or more and 13 times or less.

(evaporation film)
The barrier substrate has a deposited film made of an inorganic oxide. The barrier substrate, in one embodiment, comprises a vapor-deposited film on the surface coat layer. In one embodiment, the barrier substrate has a deposited film on the surface resin layer. Thereby, the gas barrier property of the barrier laminate, specifically, the oxygen barrier property and the water vapor barrier property can be improved. A packaging container produced using a barrier laminate can suppress a decrease in the mass of contents filled in the packaging container.

Examples of inorganic oxides include aluminum oxide (alumina), silicon oxide (silica), magnesium oxide, calcium oxide, zirconium oxide, titanium oxide, boron oxide, hafnium oxide, barium oxide, and silicon oxide carbide (carbon-containing silicon oxide). is mentioned. Among these, silica, silicon carbide oxide and alumina are preferred.

In one embodiment, silica is more preferable as the inorganic oxide because it does not require an aging treatment after deposition film formation. In one embodiment, carbon-containing silicon oxide is more preferable as the inorganic oxide, because it is possible to suppress deterioration of the gas barrier property even when the barrier laminate is bent.

The thickness of the deposited film is preferably 1 nm or more and 150 nm or less, more preferably 5 nm or more and 60 nm or less, and still more preferably 10 nm or more and 40 nm or less. When the thickness is at least the lower limit, for example, the oxygen barrier properties and water vapor barrier properties of the barrier laminate can be further improved. When the thickness is equal to or less than the upper limit, for example, the occurrence of cracks in the deposited film can be suppressed, and the recyclability of the packaging container can be improved.

The surface of the deposited film is preferably subjected to the surface treatment described above. This can improve the adhesion between the deposited film and the adjacent layer.

Examples of methods for forming a deposited film include physical vapor deposition methods (physical vapor deposition methods, PVD methods) such as vacuum deposition methods, sputtering methods and ion plating methods, plasma chemical vapor deposition methods, and thermal chemical vapor deposition methods. A chemical vapor deposition method (Chemical Vapor Deposition method, CVD method) such as a growth method and a photochemical vapor deposition method can be used.

The vapor deposition film may be a single layer formed by one vapor deposition process, or may be a multilayer film formed by multiple vapor deposition processes. When the deposited film is multilayered, each layer may be composed of the same inorganic oxide, or may be composed of different inorganic oxides. Each layer may be formed by the same method or by different methods.

A plasma-assisted vacuum film forming apparatus can be used as the apparatus used in the method of forming a deposited film by the PVD method. An embodiment of a vapor deposition film forming method using a plasma-assisted vacuum film forming apparatus will be described below.

In one embodiment, as shown in FIGS. 10 and 11, the vacuum film forming apparatus includes a vacuum vessel A, an unwinding section B, a film forming drum C, a winding section D, a transport roll E, an evaporation source F, a reaction Equipped with a gas supply unit G, a deposition protection box H, a vapor deposition material I, and a plasma gun J. FIG. 10 is a schematic cross-sectional view of the vacuum film forming apparatus in the XZ plane direction. FIG. 11 is a schematic cross-sectional view of the vacuum film forming apparatus in the XY plane direction.

As shown in FIG. 10, in the upper part of the vacuum vessel A, the substrate S wound around the film-forming drum C method is arranged so that the surface to be formed of the vapor-deposited film faces downward. Below the film forming drum C in the container A, an electrically grounded anti-adhesion box H is arranged. An evaporation source F is arranged on the bottom surface of the anti-adhesion box H. A film-forming drum C is arranged in the vacuum vessel A so that the substrate S wound around the film-forming drum C is positioned at a position facing the upper surface of the evaporation source F with a certain gap. there is Between the unwinding section B and the film-forming drum C, and between the film-forming drum C and the winding section D, transport rolls E are arranged. The vacuum vessel A is connected with a vacuum pump (not shown). The evaporation source F holds the vapor deposition material I and includes a heating device (not shown). The reaction gas supply part G is a part for supplying a reaction gas (oxygen, nitrogen, helium, argon, mixed gas of these, etc.) that reacts with the vapor deposition material I. FIG.

The evaporation source F heats and evaporates the vapor deposition material I, which is irradiated toward the substrate S. At the same time, plasma is also irradiated toward the substrate S from the plasma gun J, and a vapor deposition film is formed on the substrate S. is formed.
Details of the film formation method are disclosed in JP-A-2011-214089.

As a plasma generator used in the plasma chemical vapor deposition method, a generator for high-frequency plasma, pulse wave plasma, microwave plasma, or the like can be used. An apparatus having two or more film formation chambers may be used. Such an apparatus is preferably equipped with a vacuum pump so that each film forming chamber can be kept under vacuum.
The degree of vacuum in each film forming chamber is preferably 1×10 to 1×10 ⁻⁶ Pa.

An embodiment of a deposition film forming method using a plasma generator will be described below.
The substrate is delivered to the film forming chamber and transported onto the peripheral surface of the cooling/electrode drum at a predetermined speed via an auxiliary roll. Next, from the gas supply device, a mixed gas composition containing a film-forming monomer gas containing an inorganic oxide, an oxygen gas, an inert gas, and the like is supplied into the film-forming chamber, and a plasma is generated on the substrate by glow discharge. It is generated and irradiated to form a deposited film containing an inorganic oxide on the substrate.
Details of the film formation method are disclosed in Japanese Patent Application Laid-Open No. 2012-076292.

FIG. 12 is a schematic configuration diagram showing a plasma enhanced chemical vapor deposition apparatus used for the CVD method.
In one embodiment, as shown in FIG. 12, the plasma enhanced chemical vapor deposition apparatus unwinds the substrate S from an unwinding section B1 arranged in the vacuum vessel A1, and transfers the substrate S via the transport roll E1. is conveyed onto the peripheral surface of the cooling/electrode drum C1 at a predetermined speed. Oxygen, nitrogen, helium, argon and mixed gases thereof are supplied from the reaction gas supply part G1, and a monomer gas for film formation is supplied from the raw material gas supply part I1 to prepare a mixed gas composition for vapor deposition consisting of them. While introducing the vapor deposition mixed gas composition into the vacuum vessel A1 through the raw material supply nozzle H1, plasma is generated by the glow discharge plasma F1 on the substrate S conveyed onto the peripheral surface of the cooling/electrode drum C1. A vapor deposition film is formed on the substrate S by irradiating it. At this time, the cooling/electrode drum C1 is supplied with a predetermined power from a power source K1 arranged outside the vacuum vessel A1, and a magnet J1 is arranged near the cooling/electrode drum C1 to generate plasma. promotes the occurrence of Subsequently, after forming a vapor deposition film, the base material S is wound up by the winding part D1 via the conveyance roll E1 at predetermined winding speed. In FIG. 12, L1 represents a vacuum pump.

A continuous vapor deposition film forming apparatus having a plasma pretreatment chamber and a film forming chamber can be used as an apparatus used in the vapor deposition film forming method. An embodiment of a vapor deposition film forming method using the apparatus will be described below.

In the plasma pretreatment chamber, the substrate is irradiated with plasma from the plasma supply nozzle. Next, in the film forming chamber, a vapor deposition film is formed on the plasma-treated substrate.
Details of the film formation method are disclosed in International Publication No. 2019/087960.

The vapor-deposited film on the barrier substrate is preferably a vapor-deposited film formed by a CVD method, and more preferably a carbon-containing silicon oxide vapor-deposited film formed by a CVD method. As a result, deterioration of the gas barrier property can be suppressed even when the barrier laminate is bent.

The carbon-containing silicon oxide deposited film contains silicon, oxygen and carbon.
In one embodiment of the carbon-containing silicon oxide deposited film, the proportion C of carbon is preferably 3% or more and 50% or less, more preferably 5% or more and 40% with respect to the total 100% of the three elements of silicon, oxygen and carbon. % or less, more preferably 10% or more and 35% or less. By setting the ratio C of carbon within the above range, for example, deterioration of the gas barrier property can be suppressed even when the barrier laminate is bent.
In this specification, the ratio of each element is on a molar basis.

In one embodiment of the carbon-containing silicon oxide deposited film, the ratio Si of silicon is preferably 1% or more and 45% or less, more preferably 3% or more and 38% with respect to a total of 100% of the three elements of silicon, oxygen and carbon. % or less, more preferably 8% or more and 33% or less. The oxygen ratio O is preferably 10% or more and 70% or less, more preferably 20% or more and 65% or less, and still more preferably 25% or more and 60% or less with respect to 100% in total of the three elements of silicon, oxygen, and carbon. is. By setting the proportion Si of silicon and the proportion O of oxygen within the above ranges, for example, deterioration of gas barrier properties can be further suppressed even when the barrier laminate is bent.

In one embodiment of the carbon-containing silicon oxide deposited film, the oxygen proportion O is preferably higher than the carbon proportion C, and the silicon proportion Si is preferably lower than the carbon proportion C. The proportion O of oxygen is preferably higher than the proportion Si of silicon, ie the respective proportions preferably decrease in the order of proportion O, proportion C and proportion Si. As a result, for example, even if the barrier laminate is bent, deterioration of the gas barrier properties can be further suppressed.

The proportion C, the proportion Si and the proportion O in the carbon-containing silicon oxide deposited film can be measured by narrow scan analysis under the following measurement conditions by X-ray photoelectron spectroscopy (XPS).

(Measurement condition)
Equipment used: "ESCA-3400" (manufactured by Kratos)
[1] Spectrum collection conditions Incident X-ray: MgKα (monochromatic X-ray, hν = 1253.6 eV)
X-ray output: 150W (10kV/15mA)
X-ray scanning area (measurement area): about 6mmφ
Photoelectron capture angle: 90 degrees [2] Ion sputtering conditions Ion species: Ar ⁺
Acceleration voltage: 0.2 (kV)
Emission current: 20 (mA)
Etching range: 10mmφ
Ion sputtering time: 30 seconds, spectrum collected

(Barrier coat layer)
In one embodiment, the barrier substrate can further include a barrier coat layer on the deposited film. That is, the barrier substrate may further include a barrier coat layer on the surface of the deposited film opposite to the polypropylene resin layer side. Thereby, for example, the oxygen barrier property and water vapor barrier property of the barrier laminate can be improved.

In one embodiment, the barrier coat layer contains a gas barrier resin. Gas barrier resins include, for example, ethylene-vinyl alcohol copolymer, polyvinyl alcohol, polyacrylonitrile, polyester, polyamides such as nylon 6, nylon 6,6 and poly-metaxylylene adipamide, polyurethanes, and (meth)acrylic resins. is mentioned.

The content of the gas barrier resin in the barrier coat layer is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more. With such a configuration, for example, the gas barrier properties of the barrier coat layer can be improved.
The barrier coat layer may contain the above additives.

The thickness of the barrier coat layer containing the gas barrier resin is preferably 0.01 μm or more and 10 μm or less, more preferably 0.1 μm or more and 5 μm or less. By setting the thickness of the barrier coat layer to 0.01 μm or more, for example, gas barrier properties can be further improved. By setting the thickness of the barrier coat layer to 10 μm or less, for example, the processability of the barrier laminate and the recyclability of the packaging container can be improved.

The barrier coat layer can be formed, for example, by applying and drying a coating liquid obtained by dissolving or dispersing a material such as a gas barrier resin in water or a suitable organic solvent.

In another embodiment, the barrier coat layer is prepared by mixing a metal alkoxide, a water-soluble polymer, and optionally a silane coupling agent, and optionally adding water, an organic solvent, and a sol-gel catalyst. It is a gas barrier coating film formed by applying the obtained gas barrier composition on a deposited film and drying it. The gas barrier coating film contains a hydrolyzed polycondensate obtained by hydrolyzing and polycondensing the metal alkoxide or the like by a sol-gel method. By providing such a barrier coat layer on the vapor deposition film, it is possible to effectively suppress the occurrence of cracks in the vapor deposition film.

A metal alkoxide is represented by Formula (1), for example.
^{R1nM (} _OR2 ) _m (1)
In formula (1), R ¹ and R ² each independently represent an organic group having 1 to 8 carbon atoms, M represents a metal atom, n represents an integer of 0 or more, and m is an integer of 1 or more. and n+m represents the valence of M.

Examples of organic groups for R ¹ and R ² include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group, n-hexyl group and Examples thereof include alkyl groups having 1 to 8 carbon atoms such as n-octyl group.
Metal atom M is, for example, silicon, zirconium, titanium or aluminum.

Examples of metal alkoxides include alkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane.

Examples of water-soluble polymers include hydroxyl group-containing polymers such as polyvinyl alcohol and ethylene-vinyl alcohol copolymers. Either one of polyvinyl alcohol and ethylene-vinyl alcohol copolymer may be used, or both may be used in combination, depending on desired physical properties such as oxygen barrier properties, water vapor barrier properties, water resistance, and weather resistance. Alternatively, a gas barrier coating film obtained using polyvinyl alcohol and a gas barrier coating film obtained using an ethylene-vinyl alcohol copolymer may be laminated. The amount of the water-soluble polymer used is preferably 5 parts by mass or more and 500 parts by mass or less with respect to 100 parts by mass of the metal alkoxide.

On the surface of the gas barrier coating film, the ratio of silicon atoms to carbon atoms (Si/C) measured by X-ray photoelectron spectroscopy (XPS) is preferably 1.60 or less, more preferably 0.50 or more. 0.60 or less, more preferably 0.90 or more and 1.35 or less. When the above ratio is equal to or less than the upper limit, for example, deterioration of the gas barrier property can be suppressed even when the barrier laminate is bent. When the above ratio is at least the lower limit value, for example, when a packaging container is produced using the barrier laminate, deterioration of the gas barrier property can be suppressed even if heating such as heat sealing is performed.

The above range of the ratio of silicon atoms to carbon atoms can be achieved by appropriately adjusting the amount of metal alkoxide used relative to the water-soluble polymer. As used herein, the ratio of silicon atoms to carbon atoms is on a molar basis.

The ratio of silicon atoms to carbon atoms by X-ray photoelectron spectroscopy (XPS) can be measured by narrow scan analysis under the following measurement conditions.

(Measurement condition)
Equipment used: "ESCA-3400" (manufactured by Kratos)
[1] Spectrum collection conditions Incident X-ray: MgKα (monochromatic X-ray, hν = 1253.6 eV)
X-ray output: 150W (10kV/15mA)
X-ray scanning area (measurement area): about 6mmφ
Photoelectron capture angle: 90 degrees [2] Ion sputtering conditions Ion species: Ar ⁺
Acceleration voltage: 0.2 (kV)
Emission current: 20 (mA)
Etching range: 10mmφ
Ion sputtering time: 30 seconds + 30 seconds + 60 seconds (total 120 seconds),
Acquire spectrum

As the silane coupling agent, known organic reactive group-containing organoalkoxysilanes can be used, and organoalkoxysilanes having an epoxy group are preferred, such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxy Propylmethyldiethoxysilane and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane are included. The amount of the silane coupling agent used is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the metal alkoxide.

The gas barrier composition may contain water in a proportion of preferably 0.1 mol or more and 100 mol or less, more preferably 0.5 mol or more and 60 mol or less, relative to 1 mol of the metal alkoxide. By making the water content equal to or higher than the lower limit, for example, the oxygen barrier properties and water vapor barrier properties of the barrier laminate can be improved. By making the water content equal to or less than the upper limit, for example, the hydrolysis reaction can be carried out quickly.

The gas barrier composition may contain an organic solvent. Organic solvents include, for example, methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol and n-butyl alcohol.

As the sol-gel process catalyst, an acid or amine compound is preferable.
Acids include, for example, mineral acids such as sulfuric acid, hydrochloric acid and nitric acid; and organic acids such as acetic acid and tartaric acid. The amount of the acid to be used is preferably 0.001 mol or more and 0.05 mol or less per 1 mol of the total molar amount of the metal alkoxide and the alkoxide portion (for example, silicate portion) of the silane coupling agent.

As the amine compound, tertiary amines that are substantially insoluble in water and soluble in organic solvents are suitable, such as N,N-dimethylbenzylamine, tripropylamine, tributylamine and tripentylamine. Amines are mentioned. The amount of the amine compound used is preferably 0.01 parts by mass or more and 1.0 parts by mass or less, more preferably 0.03 parts by mass or more, relative to 100 parts by mass of the total amount of the metal alkoxide and the silane coupling agent. It is 0.3 parts by mass or less.

Examples of the method of applying the gas barrier composition include application means such as roll coating such as gravure roll coater, spray coating, spin coating, dipping, brush, bar coating and applicator.

An embodiment of a method for forming a gas barrier coating film will be described below.
A gas barrier composition is prepared by mixing a metal alkoxide, a water-soluble polymer, a sol-gel catalyst, water, an organic solvent, and optionally a silane coupling agent. A polycondensation reaction proceeds gradually in the composition. The above composition is applied onto the vapor-deposited film by a conventional method and dried. This drying further promotes polycondensation of the metal alkoxide and the water-soluble polymer (and the silane coupling agent if the composition contains a silane coupling agent) to form a composite polymer layer. The above operation may be repeated to laminate a plurality of composite polymer layers. For example, the applied composition is heated at a temperature of preferably 20° C. to 150° C., more preferably 50° C. to 120° C., still more preferably 70° C. to 100° C. for 1 second to 10 minutes. Thereby, a gas barrier coating film can be formed.

The thickness of the gas barrier coating film is preferably 0.01 μm or more and 100 μm or less, more preferably 0.1 μm or more and 50 μm or less, and still more preferably 0.1 μm or more and 5 μm or less. As a result, for example, the gas barrier property can be improved, the occurrence of cracks in the deposited film can be suppressed, and the recyclability of the packaging container can be improved.

<Polypropylene resin substrate>
The barrier laminate of the present disclosure may include a first substrate, a first adhesive layer, a second substrate, a second adhesive layer, and a sealant layer in this order in the thickness direction. preferable. The polypropylene resin base constitutes the first base or the second base.
The polypropylene resin base material is composed of polypropylene. By providing the barrier laminate with a base material composed of polypropylene, for example, the oil resistance of packaging containers produced using the barrier laminate can be improved.

Polypropylene may be homopolymer, random copolymer or block copolymer, or may be a mixture of two or more selected from these. These details are as described above.

Among polypropylenes, homopolymers or random copolymers are preferably used from the viewpoint of transparency. When the rigidity and heat resistance of the packaging container are important, it is preferable to use a homopolymer. When the impact resistance of the packaging container is important, it is preferable to use a random copolymer.

In one embodiment, the MFR of polypropylene may be 0.1 g/10 min or more and 50 g/10 min or less, or 0.3 g/10 min or more and 30 g/10 min or less, from the viewpoint of film formability and processability.

As the polypropylene, biomass-derived polypropylene, mechanically recycled or chemically recycled polypropylene may be used.

The content of polypropylene in the polypropylene resin substrate is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, and even more preferably 95% by mass or more.

The polypropylene resin substrate may contain resin materials other than polypropylene. Examples of resin materials include polyolefins such as polyethylene, (meth)acrylic resins, vinyl resins, cellulose resins, polyamides, polyesters, and ionomer resins.
The polypropylene resin substrate may contain the above additives.

A polypropylene resin substrate is a substrate that has been stretched. Thereby, for example, the heat resistance, impact resistance, water resistance and dimensional stability of the barrier laminate can be improved. A barrier laminate comprising such a substrate is suitable as a packaging material for packaging containers that are subjected to boiling treatment or retorting treatment, for example.
The stretching treatment may be uniaxial stretching or biaxial stretching.

The draw ratio for stretching in the MD direction is preferably 2 to 15 times, more preferably 5 to 13 times. The draw ratio in stretching in the TD direction is preferably 2 times or more and 15 times or less, more preferably 5 times or more and 13 times or less. By setting the draw ratio to 2 times or more, the strength and heat resistance of the polypropylene resin base material can be further improved, and the printability of the polypropylene resin base material can be improved. From the viewpoint of breaking limit of the polypropylene resin substrate, the draw ratio is preferably 15 times or less.

In one embodiment, the polypropylene resin substrate may be subjected to the surface treatment described above. Thereby, for example, the adhesion between the polypropylene resin substrate and other layers can be improved.
An easy-adhesion layer may be provided on the surface of the polypropylene resin substrate.

The polypropylene resin substrate may have a single layer structure or a multilayer structure.
The thickness of the polypropylene resin substrate is preferably 10 μm or more and 100 μm or less, more preferably 10 μm or more and 50 μm or less. When the thickness is at least the lower limit, for example, the strength and heat resistance of the barrier laminate can be further improved. When the thickness is equal to or less than the upper limit, for example, the processability of the barrier laminate can be further improved. The method for forming the printed layer is as described above.

The barrier laminate may have a printed layer on the surface of the polypropylene resin substrate. The image formed on the printed layer is not particularly limited, and may be letters, patterns, symbols, combinations thereof, or the like. The printing layer can also be formed using a biomass-derived ink. As a result, the environmental load can be further reduced.

<Sealant layer>
The barrier laminate of the present disclosure comprises a sealant layer.
The sealant layer, in one embodiment, contains a resin material that can be fused together by heat. Examples of resin materials that can be fused together by heat include polyolefins, and specific examples include polyethylenes such as low-density polyethylene, linear low-density polyethylene and medium-density polyethylene, polypropylene, polybutene, and methylpentene polymers. , as well as cyclic olefin copolymers.

Examples of resin materials that can be mutually fused by heat include ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylate copolymer, ) Ethyl acrylate copolymer, ethylene-vinyl alcohol copolymer, ionomer resin, polyolefin modified with unsaturated carboxylic acid such as (meth)acrylic acid, maleic acid, maleic anhydride, fumaric acid and itaconic acid. Also included are polyolefins, polyesters such as polyethylene terephthalate, polyvinyl acetate, polyvinyl chloride and (meth)acrylic resins.

The sealant layer, in one embodiment, is composed of polypropylene. In this embodiment, the sealant layer is made of the same type of resin material as the polypropylene resin layer and the polypropylene resin substrate, that is, polypropylene. As a result, the packaging container can be made of a monomaterial. After recovering the used packaging container, there is no need to separate the base material and the sealant layer, and the recyclability of the packaging container can be improved. By configuring the sealant layer with polypropylene, the oil resistance of the packaging container produced using the barrier laminate can also be improved.

The polypropylene content in the sealant layer is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, and even more preferably 95% by mass or more. Thereby, for example, the recyclability of the packaging container can be improved.

When the sealant layer is made of polypropylene, the content of polypropylene relative to the total amount of resin materials contained in the barrier laminate is preferably 80% by mass or more, more preferably 85% by mass or more, and still more preferably 88% by mass or more. , particularly preferably 90% by mass or more. As a result, for example, a monomaterial packaging container can be produced using the barrier laminate, and the recyclability of the packaging container can be improved.

Polypropylene includes, for example, propylene homopolymers, propylene random copolymers such as propylene-α-olefin random copolymers, and propylene block copolymers such as propylene-α-olefin block copolymers. Details of the α-olefin are as described above. From the viewpoint of heat sealability, the density of polypropylene is, for example, 0.88 g/cm ³ or more and 0.92 g/cm ³ or less. Density is measured according to JIS K7112, particularly D method (density gradient tube method, 23°C). From the viewpoint of reducing environmental load, biomass-derived polypropylene and/or recycled polypropylene may be used.
The sealant layer may contain the above additives.

The sealant layer may have a single layer structure or a multilayer structure.
The thickness of the sealant layer is preferably 10 μm or more and 200 μm or less, more preferably 20 μm or more and 150 μm or less. When the thickness is at least the lower limit value, for example, the lamination strength of the packaging container provided with the barrier laminate can be further improved. When the thickness is equal to or less than the upper limit, for example, the processability of the barrier laminate can be further improved. When a pouch (particularly a retort pouch) is produced from the barrier laminate, the thickness of the sealant layer is more preferably 30 μm or more and 100 μm or less.

From the viewpoint of heat sealability, the sealant layer is preferably an unstretched resin film, more preferably an unstretched polypropylene resin film. The resin film can be produced by using, for example, a casting method, a T-die method, an inflation method, or the like.

For example, an unstretched resin film corresponding to the sealant layer may be laminated on the second substrate via an adhesive layer, if necessary, and a resin material that can be fused to each other by heat may be laminated on the second substrate. The sealant layer may be formed by melt extrusion onto the material. Examples of the adhesive layer include the following adhesive layers.

<Adhesive layer>
The barrier laminate of the present disclosure includes an adhesive layer having a thickness of 2 μm or less between the substrate and the sealant layer. In one embodiment, the barrier laminate of the present disclosure includes a first adhesive layer having a thickness of 2 μm or less between the first substrate and the second substrate, and the second substrate and the sealant A second adhesive layer having a thickness of 2 μm or less is provided between the layers. This can improve the adhesion between the substrate and the sealant layer, the adhesion between the first substrate and the second substrate, and/or the adhesion between the second substrate and the sealant layer.

The thickness of the adhesive layers such as the first adhesive layer and the second adhesive layer is 2 μm or less, preferably 0.1 μm or more and 2 μm or less, more preferably 0.2 μm or more and 2 μm or less, and still more preferably 0.5 μm. It is more than 2 micrometers or less. Thereby, for example, the amount of residual solvent in the barrier laminate can be reduced.

The adhesive forming the first adhesive layer and the adhesive forming the second adhesive layer may be the same or different.

The adhesive layers such as the first adhesive layer and the second adhesive layer are made of adhesive. The adhesive may be a one-component curing adhesive, a two-component curing adhesive, or a non-curing adhesive. The barrier laminate of the present disclosure, in one embodiment, comprises at least three elements: a polypropylene resin substrate, a barrier substrate and a sealant layer. As a result, when a laminate is manufactured using an adhesive, the laminate can be manufactured without applying the adhesive directly onto the vapor deposition film, and deterioration of the vapor deposition film can be suppressed.

The adhesive may be a non-solvent type adhesive or a solvent type adhesive, but from the viewpoint of reducing the amount of residual solvent in the barrier laminate, the non-solvent type adhesive is preferred.

Examples of solvent-based adhesives include rubber-based adhesives, vinyl-based adhesives, olefin-based adhesives, silicone-based adhesives, epoxy-based adhesives, phenol-based adhesives, and urethane-based adhesives.

Solvent-free adhesives, that is, non-solvent laminate adhesives include, for example, polyether-based adhesives, polyester-based adhesives, silicone-based adhesives, epoxy-based adhesives, and urethane-based adhesives. Among these, urethane-based adhesives are preferred, and two-liquid curing urethane-based adhesives are more preferred.

The solventless adhesive is, in one embodiment, a two-component curing adhesive having a main agent and a curing agent. The weight average molecular weight (Mw) of the polymer component contained in the main agent is preferably 800 or more and 10,000 or less, more preferably 1,200 or more and 4,000 or less, from the viewpoint of coatability. The polydispersity (Mw/Mn) of the polymer component contained in the main agent is preferably 2.8 or less, more preferably 1.2 or more and 2.7 or less, still more preferably 1.5 or more and 2.6 or less, especially It is preferably 2.0 or more and 2.5 or less. Here, Mn is the number average molecular weight of the polymer component contained in the main agent. Each average molecular weight is measured by gel permeation chromatography (GPC) in accordance with JIS K7252-1 (2008) and is a polystyrene-equivalent value.

In the present disclosure, by forming the adhesive layer using a solvent-free adhesive, for example, the amount of residual solvent, specifically the amount of residual organic solvent, in the barrier laminate can be further reduced. A laminate of the present disclosure includes a polypropylene resin layer. The barrier laminate of the present disclosure, in one embodiment, comprises a polypropylene resin layer and a polypropylene resin substrate. Therefore, when the barrier laminate of the present disclosure is produced using a solvent-based adhesive, it is necessary to lower the temperature during drying in order to prevent deterioration and heat shrinkage of the laminate compared to polyester-based laminates. There is In this case, the solvent in the adhesive may not be sufficiently removed by volatilization and may remain in the barrier laminate, leaving an odor due to the residual solvent. By using a non-solvent type adhesive, the amount of residual solvent can be further reduced.

Examples of the organic solvent include hydrocarbon solvents such as toluene, xylene, n-hexane and methylcyclohexane; ester solvents such as ethyl acetate, n-propyl acetate, n-butyl acetate and isobutyl acetate; methanol, ethanol and isopropyl alcohol. , n-butyl alcohol and isobutyl alcohol; and ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone.

In one embodiment, the use of solvent-free adhesives allows, for example, a thinner adhesive layer than the use of solvent-based adhesives. Thereby, the content of polypropylene in the entire barrier laminate can be further improved. Such a barrier laminate is suitable for manufacturing monomaterial packaging containers.

In one embodiment, by using a solvent-free adhesive, the tearability of the barrier laminate can be further improved as described later, compared to the case of using a solvent-based adhesive. The improvement in tearability is achieved by using a non-solvent type adhesive to make the adhesive layer thinner and harder.

In one embodiment of the barrier laminate of the present disclosure, the substrate and the resin film corresponding to the sealant layer are laminated using a non-solvent lamination method using a solvent-free adhesive or a solvent-based adhesive. It can be manufactured by laminating by a dry lamination method or the like. In one embodiment, the barrier laminate of the present disclosure is a non-solvent lamination using a solvent-free adhesive, comprising a first substrate, a second substrate, and a resin film corresponding to the sealant layer. or a dry lamination method using a solvent-based adhesive.

A solvent-free, two-liquid curing urethane-based adhesive will be described below. As this urethane-based adhesive, for example, an adhesive having a main agent containing a polyol compound such as polyester polyol and a curing agent containing an isocyanate compound is preferable.
Polyol compounds include, for example, polyester polyols, polyether polyols, polycarbonate polyols and (meth)acrylic polyols. Among these, polyester polyols are preferred.

A polyester polyol has two or more hydroxyl groups in one molecule. A polyester polyol has, for example, a polyester structure or a polyester polyurethane structure as a main skeleton. A polyester polyol is obtained, for example, by dehydration condensation reaction, transesterification or ring-opening reaction between a polyhydric alcohol component and a polycarboxylic acid component.

Examples of polyhydric alcohol components include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6- diols such as hexanediol, neopentyl glycol and cyclohexanedimethanol; trifunctional or higher polyols such as glycerin, triethylolpropane, trimethylolpropane, pentaerythritol and sorbitol.

Examples of polyvalent carboxylic acid components include aliphatic polyvalent carboxylic acids, alicyclic polyvalent carboxylic acids, aromatic polyvalent carboxylic acids, and ester derivatives and acid anhydrides thereof. Examples of aliphatic polycarboxylic acids include aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, maleic acid, fumaric acid and dimer acid. Alicyclic polyvalent carboxylic acids include, for example, 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. Examples of aromatic polycarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid and 1,2-bis(phenoxy)ethane-p , p′-dicarboxylic acids.

Polyester polyols can also be pre-chain lengthened with polyisocyanates if desired. Examples of polyisocyanates include 1,6-hexamethylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, m-xylylene diisocyanate, α, α, α'α'-tetramethyl-m-xylylene diisocyanate, tolylene diisocyanate, and naphthalene. diisocyanates and diisocyanates such as diphenylmethane diisocyanate; and burettes, nurates and trimethylolpropane adducts of diisocyanates.

The weight average molecular weight (Mw) of the polyol compound such as polyester polyol is preferably 800 or more and 10,000 or less, more preferably 1,200 or more and 4,000 or less, from the viewpoint of coatability. The polydispersity (Mw/Mn) of the polyol compound such as polyester polyol is preferably 2.8 or less, more preferably 1.2 or more and 2.7 or less, still more preferably 1.5 or more and 2.6 or less, and particularly preferably is 2.0 or more and 2.5 or less. Here, Mn is the number average molecular weight of the polyol compound. Each average molecular weight is measured by gel permeation chromatography (GPC) in accordance with JIS K7252-1 (2008) and is a polystyrene-equivalent value.

The isocyanate compound has two or more isocyanate groups in one molecule.
Isocyanate compounds include, for example, aromatic isocyanates and aliphatic isocyanates. The isocyanate compound may be a blocked isocyanate compound obtained by addition reaction using a known isocyanate blocking agent by a known and commonly used appropriate method.

Examples of isocyanate compounds include tetramethylene diisocyanate, hexamethylene diisocyanate, norbornene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, m-xylylene diisocyanate, hydrogenated xylylene diisocyanate, tolylene diisocyanate, naphthalene diisocyanate and α, Diisocyanates such as α,α'α'-tetramethyl-m-xylylene diisocyanate; trimers of these diisocyanates; Examples include adducts, burettes and allophanates obtained by reacting with hydrogen compounds.

Examples of low-molecular-weight active hydrogen compounds include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,4-butanediol, neneopentyl glycol, 1,6-hexamethylene glycol, 1,8-octamethylene glycol, 1,4-cyclohexanedimethanol, metaxylylene alcohol, 1,3-bishydroxyethylbenzene, 1,4-bishydroxyethylbenzene, trimethylolethane, trimethylolpropane, glycerol, pentaerythritol, erythritol, sorbitol, ethylenediamine, monoethanol Amines, diethanolamine, triethanolamine and meta-xylylenediamine are included. Polymeric active hydrogen compounds include, for example, polyesters, polyether polyols and polyamides.

<Physical properties>
The residual solvent content in the barrier laminate of the present disclosure is 10 mg/m ² or less, more preferably 5 mg/m ² or less, still more preferably 3 mg/m ² or less, 2 mg/m ² or less, or 1 mg/m ^{2 .} It is below. The lower limit of the residual solvent amount is preferably as small as possible, but may be, for example, 0.1 mg/m ² or 0.2 mg/m ² .

The amount of residual solvent can be measured by cutting out a 10 cm square sample from the barrier laminate and measuring the sample using, for example, a gas chromatograph GC-2014 manufactured by Shimadzu Corporation, according to a calibration curve method.

The barrier laminate of the present disclosure exhibits the following tear strength in one embodiment.
Tearing strength is measured as follows. A sample was prepared by stacking 16 barrier laminates alternately on the front and back so that the MD and TD directions of the films constituting the barrier laminate were aligned. The tear strength in the MD direction and the TD direction of the sample was measured according to JIS K7128-2 (Elmendorf tearing method) using, for example, No. 1 manufactured by Toyo Seiki Seisakusho. 163 Elmendorf Tear Tester.

The tear strength (unit: N/16 sheets) in the MD direction of the barrier laminate is, for example, 0.1 or more and 2.0 or less, preferably 0.2 or more and 1.5 or less. Thereby, the unsealability in the MD direction of the packaging container composed of the barrier laminate can be improved.

The tear strength in the TD direction (unit: N/16 sheets) of the barrier laminate is, for example, 0.1 or more and 3.5 or less, preferably 0.2 or more and 3.0 or less, and more preferably 0.5 or more. 2.5 or less. Thereby, the unsealability in the TD direction of the packaging container composed of the barrier laminate can be improved. For example, when a barrier laminate is produced, the tear strength in the TD direction can be reduced by using a non-solvent adhesive.

The ratio of the tear strength in the TD direction to the tear strength in the MD direction (strength _TD /strength _MD ) of the barrier laminate is, for example, 5.0 or less, more preferably 4.5 or less, and still more preferably 4.0 or less. be. Although the lower limit of the above ratio is not particularly limited, it may be, for example, 1.0, 1.5 or 2.0. Thereby, the unsealability in the TD direction of the packaging container composed of the barrier laminate can be improved.

The barrier laminate of the present disclosure exhibits the following thermal shrinkage in one embodiment. The MD direction refers to the flow direction of the laminate, and the TD direction refers to the direction perpendicular to the MD direction.

The thermal shrinkage (MD1) in the MD direction of the barrier laminate after heat treatment at 120°C for 15 minutes is, for example, 2.00% or less, preferably 1.20% or less, more preferably 1.00%. 0.90% or less, more preferably 0.90% or less. The lower limit of the thermal shrinkage (MD1) is preferably as low as possible, but may be 0.10% or 0.20%, for example. A barrier laminate having such a small heat shrinkage (MD1) has excellent gas barrier properties and excellent suitability for bag making when a packaging bag is produced by heat sealing.

The thermal shrinkage rate (TD1) in the TD direction of the barrier laminate after heat treatment at 120° C. for 15 minutes is, for example, 2.00% or less, preferably 1.50% or less, more preferably 1.30%. It is below. The lower limit of the thermal shrinkage rate (TD1) is preferably as low as possible, but may be, for example, 0.10%, 0.20% or 0.50%. A barrier laminate having such a low thermal shrinkage (MD1) as well as a low thermal shrinkage (TD1) is even more excellent in gas barrier properties and bag-making aptitude. For example, it is possible to suppress the occurrence of wrinkles, deformation, etc. in a packaging bag produced by heat sealing. In particular, when the thermal shrinkage (TD1) is small, image distortion in the printed layer of the barrier laminate can be suppressed.

The ratio (MD1/TD1) of the thermal shrinkage rate (MD1) to the thermal shrinkage rate (TD1) of the barrier laminate after heat treatment at 120° C. for 15 minutes is, for example, 0.30 or more and 3.00 or less. It is preferably 0.35 or more and 2.00 or less, more preferably 0.40 or more and 1.50 or less. If the ratio (MD1/TD1) is within such a range, the laminate shrinks relatively uniformly in the MD and TD directions even when subjected to heat treatment. Distortion can be suppressed.

The thermal shrinkage rate (MD2) in the MD direction of the barrier laminate after heat treatment at 150°C for 5 minutes is, for example, 4.00% or less, preferably 3.50% or less, more preferably 3.10%. It is below. The lower limit of the thermal shrinkage (MD2) is preferably as low as possible, but may be, for example, 0.50% or 1.00%.

The thermal shrinkage rate (TD2) in the TD direction of the barrier laminate after heat treatment at 150°C for 5 minutes is, for example, 4.00% or less, preferably 3.50% or less, more preferably 2.80%. It is below. The lower limit of the thermal shrinkage (TD2) is preferably as low as possible, but may be, for example, 0.50% or 1.00%.

The ratio (MD2/TD2) of the thermal shrinkage rate (MD2) and the thermal shrinkage rate (TD2) of the barrier laminate after heat treatment at 150° C. for 5 minutes is, for example, 0.30 or more and 3.00 or less. It is preferably 0.40 or more and 2.00 or less, more preferably 0.50 or more and 1.60 or less.

Each thermal contraction rate is calculated by the following formula.
Thermal shrinkage (MD) (%) = (length in MD direction of laminate before heat treatment - length in MD direction of laminate after heat treatment)/length in MD direction of laminate before heat treatment ×100
Thermal shrinkage (TD) (%) = (length in the TD direction of the laminate before heat treatment - length in the TD direction of the laminate after heat treatment) / length in the TD direction of the laminate before heat treatment ×100

[Packaging container]
The barrier laminate of the present disclosure can be suitably used for packaging materials.
Packaging materials are used to make packaging containers. A packaging material comprises the barrier laminate of the present disclosure. A packaging container can be produced by using at least a packaging material comprising the barrier laminate of the present disclosure.

The packaging container of the present disclosure includes the barrier laminate of the present disclosure (hereinafter also simply referred to as "laminate"). Packaging containers include, for example, packaging bags, tube containers, and containers with lids. A lidded container includes a container body having an accommodating portion, and a lid member joined (heat-sealed) to the container body so as to seal the accommodating portion.

In one embodiment, the packaging container of the present disclosure maintains gas barrier properties even when subjected to high-temperature treatment, and is less deformable, and is therefore suitable as a microwave oven container, or a boil or retort container. The packaging container of the present disclosure is also suitable as a microwave boiler or retort container. The packaging container of the present disclosure is particularly suitable as a boil or retort pouch.

Methods of heat sealing include, for example, bar sealing, rotary roll sealing, belt sealing, impulse sealing, high frequency sealing and ultrasonic sealing.

As packaging bags, for example, standing pouch type, side seal type, two side seal type, three side seal type, four side seal type, envelope pasted seal type, palm pasted seal type (pillow seal type), plaited seal type, flat bottom seal. There are various types of packaging bags such as type, square bottom seal type and gusset type.

The packaging container may be provided with an easy-open part. The easy-to-open portion includes, for example, a notch portion serving as a starting point for tearing the packaging container, and a half-cut line formed by laser processing, a cutter, or the like as a path for tearing the packaging container.

The packaging container may be provided with a steam release mechanism. When the steam pressure inside the packaging container exceeds a predetermined value, the steam venting mechanism allows the inside of the packaging container to communicate with the outside to release the steam, and also prevents the steam from escaping at locations other than the steam venting mechanism. is configured as

The steam release mechanism includes, for example, a steam release seal portion protruding toward the inside of the packaging container from the side seal portion, and a non-sealed portion separated from the contents accommodating portion by the steam release seal portion. The unsealed portion communicates with the outside of the packaging container. The packaging container filled with contents and heat-sealed at the opening is heated using a microwave oven or the like. As a result, the internal pressure increases and the steam release seal portion is peeled off. The steam escapes to the outside of the packaging container through the peeled portion of the steam releasing seal portion and the non-sealed portion.

In one embodiment, the laminate of the present disclosure is folded in half so that the first base material is located outside and the sealant layer is located inside, and the ends and the like are heat-sealed to form a packaging bag. can be made. In another embodiment, a packaging bag can be produced by stacking a plurality of laminates of the present disclosure so that the sealant layers face each other and heat-sealing the edges and the like. The entire packaging bag may be composed of the laminate, or part of the packaging bag may be composed of the laminate.

In one embodiment, the laminate of the present disclosure is used as a lid material in a lidded container. A lidded container includes a container body having an accommodating portion, and a lid member joined (heat-sealed) to the container body so as to seal the accommodating portion. Here, the lid material, that is, the sealant layer of the laminate and the container body are heat-sealed. Examples of the shape of the container body include a cup shape and a bottomed cylindrical shape. The container body is made of, for example, polystyrene, polypropylene, polyethylene or paper.

Contents contained in packaging containers include, for example, liquids, solids, powders, and gels. The contents may be food or drink, or may be non-food or drink such as chemicals, cosmetics, and pharmaceuticals. After containing the contents in the packaging container, the packaging container can be sealed by heat-sealing the opening of the packaging container.

As specific examples of packaging bags, small bags and standing pouches will be described below.
A sachet is a small packaging bag, and is used to contain, for example, 1 g or more and 200 g or less of contents. Contents contained in the sachet include, for example, sauces, soy sauce, dressings, ketchup, syrups, cooking liquors, other liquid or viscous seasonings; liquid soups, powdered soups, fruit juices; spices; Beverages, jellied beverages, ready-to-eat foods, and other food and drink.

Standing pouches are used, for example, to contain contents of 50 g or more and 2000 g or less. Contents contained in the standing pouch include, for example, shampoo, rinse, conditioner, hand soap, body soap, fragrance, deodorant, deodorant, insect repellent, detergent; dressing, edible oil, mayonnaise, and others. Liquid or viscous seasonings; liquid beverages, jelly-like beverages, instant foods, other foods and drinks; and creams.

FIG. 13 shows a packaging bag 50 obtained by pasting two laminates together. The shaded area indicates the heat-sealed portion. The packaging bag 50 may include an easy-open portion 51 . The easy-to-open portion 51 includes, for example, a notch portion 52 that is a starting point for tearing, and a half-cut line 53 that is formed by laser processing, a cutter, or the like as a path for tearing.

FIG. 14 schematically shows an example of the configuration of a standing pouch. The shaded area indicates the heat-sealed portion. Standing pouch 60 , in one embodiment, comprises a body (side sheet) 61 and a bottom (bottom sheet) 62 . The side sheet 61 and the bottom sheet 62 may be composed of the same member or may be composed of different members. Since the bottom sheet 62 retains the shape of the side sheet 61, the pouch can stand on its own and can be used as a standing pouch. A storage space for storing contents is formed in a region surrounded by the side sheet 61 and the bottom sheet 62 .

The standing pouch 60 may be provided with a steam release mechanism 63 . The steam release mechanism 63 includes a steam release seal portion 63a protruding toward the inside of the packaging container from the side seal portion, and a non-sealed portion 63b separated from the contents accommodating portion by the steam release seal portion 63a. The unsealed portion 63b communicates with the outside of the packaging container.

In the standing pouch, only the body may be composed of the laminate of the present disclosure, only the bottom may be composed of the laminate of the present disclosure, or both the body and the bottom may be composed of the laminate of the present disclosure. may

In one embodiment, the side sheet can be formed by making a bag so that the sealant layer included in the laminate of the present disclosure is the innermost layer. In one embodiment, the side sheets can be formed by preparing two laminates of the present disclosure, stacking them so that the sealant layers face each other, and heat-sealing the side edges on both sides to form a bag. .

In another embodiment, the side sheets are prepared by preparing two laminates of the present disclosure, overlapping them with the sealant layers facing each other, and separating the laminates at the side edges on both sides of the overlapped laminate. , two laminates folded in a V shape with the sealant layer on the outside are inserted and heat-sealed. Such a method of manufacture results in a standing pouch having a body with side gussets.

In one embodiment, the bottom sheet can be formed by inserting the laminate of the present disclosure between the bottoms of the bag-made side sheets and heat sealing. More specifically, the bottom sheet can be formed by inserting a laminate folded in a V-shape so that the sealant layer is on the outside between the lower parts of the bag-made side sheets, and heat-sealing.

In one embodiment, two laminates are prepared, these are superimposed so that the sealant layers face each other, and then another laminate is folded in a V shape so that the sealant layer is on the outside. , is sandwiched between the lower portions of the laminates facing each other and heat-sealed to form a bottom portion. The body is then formed by heat sealing the two sides adjacent to the bottom. In this manner, an embodiment standing pouch can be formed.

The present disclosure relates to, for example, the following [1] to [17].
[1] A barrier laminate comprising a substrate, an adhesive layer, and a sealant layer in this order in the thickness direction, wherein the substrate is a barrier substrate comprising a polypropylene resin layer and a deposited film, The polypropylene resin layer is a layer subjected to stretching treatment, the deposited film is composed of an inorganic oxide, the adhesive layer is a layer having a thickness of 2 μm or less, and the amount of residual solvent in the barrier laminate is , 10 mg/m ² or less.
[2] A barrier laminate comprising a first substrate, a first adhesive layer, a second substrate, a second adhesive layer, and a sealant layer in this order in the thickness direction, Either one of the first base material and the second base material is a barrier base material comprising a polypropylene resin layer and a deposited film, and the other of the first base material and the second base material is a polypropylene resin. A base material, the polypropylene resin layer is a layer subjected to stretching treatment, the deposited film is composed of an inorganic oxide, and the polypropylene resin base material is a base material subjected to stretching treatment, A barrier laminate, wherein each of the first adhesive layer and the second adhesive layer is a layer having a thickness of 2 μm or less, and a residual solvent amount in the barrier laminate is 10 mg/m ² or less.
[3] The barrier laminate according to [1] or [2] above, wherein the adhesive layer is a layer formed from a non-solvent adhesive.
[4] The solvent-free adhesive is a two-component curing adhesive containing a main agent and a curing agent, and the weight average molecular weight (Mw) of the polymer component contained in the main agent is 800 or more and 10,000 or less. The barrier laminate according to [3] above.
[5] The solvent-free adhesive is a two-component curing adhesive containing a main agent and a curing agent, and the polymer component contained in the main agent has a polydispersity (Mw/Mn) of 2.8 or less. The barrier laminate according to the above [3] or [4].
[6] When the first base material is a barrier base material, the first base material is arranged so that the deposited film faces the sealant layer side and the polypropylene resin layer faces the side opposite to the sealant layer. When the second base material is a barrier base material, the second base material is arranged so that the deposited film faces the first base material side and the polypropylene resin layer faces the sealant layer side. The barrier laminate according to [2] above.
[7] The barrier laminate according to [2] or [6] above, wherein the first substrate is a polypropylene resin substrate and the second substrate is a barrier substrate.
[8] The above [1] to [7], wherein the barrier substrate further comprises a surface coat layer between the polypropylene resin layer and the deposited film, and the surface coat layer contains a resin material having a polar group. The barrier laminate according to any one of .
[9] The barrier substrate further comprises a surface resin layer between the polypropylene resin layer and the deposited film, and the surface resin layer contains a resin material having a melting point of 180° C. or higher [1] to The barrier laminate according to any one of [7].
[10] The barrier laminate according to [9] above, wherein the polypropylene resin layer and the surface resin layer in the barrier substrate are coextruded stretched resin films.
[11] The barrier laminate according to any one of [1] to [10] above, further comprising a barrier coat layer on the deposited film.
[12] The barrier laminate according to any one of [1] to [11] above, wherein the sealant layer is a resin layer made of polypropylene.
[13] The barrier laminate according to any one of [1] to [12] above, which is used for packaging containers.
[14] A packaging container comprising the barrier laminate according to any one of [1] to [13] above.
[15] The packaging container according to [14] above, which is a boil or retort pouch.
[16] A lid material comprising the barrier laminate according to any one of [1] to [13] above.
[17] A packaging container comprising a container body having an accommodating portion, and the lid member according to the above [16] joined to the container body so as to seal the accommodating portion.

Hereinafter, the barrier laminate of the present disclosure will be specifically described based on examples.

[Preparation of barrier substrate]
A hydroxyl group-containing (meth)acrylic resin (number average molecular weight: 25,000, glass transition temperature: 99°C, hydroxyl value: 80 mgKOH/g) was mixed with a mixed solvent of methyl ketone and ethyl acetate (mixing ratio: 1:1). , and diluted to a solid content concentration of 10% by mass to prepare a main agent.

An ethyl acetate solution (solid content: 75% by mass) containing tolylene diisocyanate was added as a curing agent to the main component to obtain a solution for forming a surface coat layer. The amount of curing agent used was 10 parts by mass with respect to 100 parts by mass of the main agent.

A biaxially oriented polypropylene film (ME-1, manufactured by Mitsui Chemicals Tohcello, Inc.) having a thickness of 20 μm and one surface of which was corona-treated was prepared. The corona-treated surface of the film was coated with the solution for forming a surface coat layer and dried to form a surface coat layer having a thickness of 0.5 μm, thereby obtaining a resin substrate.

On the surface coating layer of the resin substrate, a carbon-containing silicon oxide deposition film with a thickness of 12 nm is formed by roll-to-roll using an actual low-temperature plasma chemical vapor deposition apparatus while applying tension to the resin substrate. (CVD method). The deposition film formation conditions were as follows.

(Formation conditions)
・ Hexamethyldisiloxane: oxygen gas: helium = 1:10:10 (unit: slm)
・Power supplied to cooling/electrode drum: 22 kW
・Line speed: 100m/min

The ratio C of carbon, the ratio Si of silicon, and the ratio O of oxygen in the carbon-containing silicon oxide deposited film were measured. The ratio C of carbon, the ratio Si of silicon, and the ratio O of oxygen are 32.7%, 29.8%, and 37.5%, respectively, with respect to the total 100% of the three elements of silicon, oxygen, and carbon. there were. The ratio of each element was measured by X-ray photoelectron spectroscopy (XPS) by narrow scan analysis under the measurement conditions described above.

385 g of water, 67 g of isopropyl alcohol, and 9.1 g of 0.5N hydrochloric acid were mixed to obtain a solution of pH 2.2. To this solution, 175 g of tetraethoxysilane as a metal alkoxide and 9.2 g of glycidoxypropyltrimethoxysilane as a silane coupling agent were mixed while cooling to 10° C. to obtain a solution A.

Solution B was obtained by mixing 14.7 g of polyvinyl alcohol having a saponification degree of 99% or more and a degree of polymerization of 2400 as a water-soluble polymer, 324 g of water, and 17 g of isopropyl alcohol.

Solution A and solution B were mixed at a ratio of 6.5:3.5 on a mass basis to obtain a barrier coating agent. A barrier coating agent was applied onto the deposited film formed on the resin base material by spin coating, and heat-treated in an oven at 80° C. for 60 seconds to form a barrier coating layer with a thickness of 300 nm.
As described above, a transparent barrier substrate was obtained.

[Reference example 1]
The surface of the biaxially oriented polypropylene film in the transparent barrier substrate was subjected to corona treatment to adjust the wetting tension to 38 dyn or more. A 20 μm thick biaxially oriented polypropylene film (manufactured by Toyobo Co., Ltd., P2171) was used as the first substrate, and the corona-treated transparent barrier substrate was used as the second substrate, and a 60 μm thick sealant layer was used. The unstretched polypropylene film (ZK207, manufactured by Toray Advanced Film Co., Ltd.) is dried through a solvent-type polyester urethane adhesive (RU-004/H-1 (mixing ratio 7.5/1) manufactured by Rock Paint). It was laminated and allowed to stand at 40° C. for 72 hours to obtain a barrier laminate. The thickness of the adhesive layer formed from the solvent type polyester urethane adhesive was 4 μm. The content of polypropylene in the barrier laminate was 89% by mass. The weight average molecular weight (Mw) of the polymer component contained in the main agent in the solvent-type polyester urethane adhesive is in the range of 29,000 to 30,000, and the polydispersity (Mw/Mn) of the polymer component contained in the main agent ranged from 2.9 to 3.75.

A 10 cm square sample was cut out from the obtained barrier laminate. With respect to the sample, the amount of residual solvent was measured by the calibration curve method using a gas chromatograph GC-2014 manufactured by Shimadzu Corporation. The residual solvent content was 20 mg/m ² .

A sample was prepared by stacking 16 sheets of the resulting barrier laminate alternately on the front and back so that the films constituting the barrier laminate were aligned in the MD and TD directions. The tear strength in the MD direction and the TD direction of the sample was measured according to JIS K7128-2 (Elmendorf tearing method) using No. 1 manufactured by Toyo Seiki Seisakusho Co., Ltd. 163 Elmendorf Tear Tester. As a result, the tear strength in the MD direction was 0.7 N/16 sheets, the tear strength in the TD direction was 4.1 N/16 sheets, and the tear strength ratio (strength _TD /strength _MD ) was 5.9. .

[Example 1]
The surface of the biaxially oriented polypropylene film in the transparent barrier substrate was subjected to corona treatment to adjust the wetting tension to 38 dyn or more. A 20 μm thick biaxially oriented polypropylene film (manufactured by Toyobo Co., Ltd., P2171) was used as the first substrate, and the corona-treated transparent barrier substrate was used as the second substrate, and a 60 μm thick sealant layer was used. of unstretched polypropylene film (Toray Advanced Film Co., Ltd., ZK207), solvent-free polyester urethane adhesive (ROCK PAINT, RN-920/HN-920 (blending ratio 1/1)) through non-solvent It was laminated and allowed to stand at 40° C. for 72 hours to obtain a barrier laminate. The thickness of the adhesive layer formed from the non-solvent polyester urethane adhesive was 1 μm. The content of polypropylene in the barrier laminate was 95% by mass. The weight average molecular weight (Mw) of the polymer component contained in the main agent in the solventless polyester urethane adhesive is in the range of 2,000 to 2,500, and the polydispersity of the polymer component contained in the main agent (Mw/Mn ) ranged from 2.0 to 2.5.

The residual solvent content of the resulting barrier laminate was 0.7 mg/m ² .
A sample was prepared by stacking 16 sheets of the resulting barrier laminate alternately on the front and back so that the films constituting the barrier laminate were aligned in the MD and TD directions. The tear strength in the MD direction of the sample was 0.6 N/16 sheets, the tear strength in the TD direction was 1.7 N/16 sheets, and the tear strength ratio (strength _TD /strength _MD ) was 2.8. .

[Gas barrier property evaluation]
A test piece was obtained by cutting out the barrier laminate obtained above. Using this test piece, oxygen permeability (cc/m ² ·day·atm) and water vapor permeability (g/m ² ·day) were measured by the following methods.

Using an oxygen permeability measuring device (OX-TRAN2/20, manufactured by MOCON), the test piece was set so that the first base material side was on the oxygen supply side, and was measured at 23°C in accordance with JIS K 7126. , the oxygen permeability was measured under an environment of relative humidity of 90% RH.

Using a water vapor transmission rate measuring device (manufactured by MOCON, PERMATRAN-w 3/33), set the test piece so that the first substrate side is on the water vapor supply side, and measure 40 in accordance with JIS K 7129. C. and a relative humidity of 90% RH, the water vapor permeability was measured.

[Gas barrier property evaluation (after boiling treatment or after retort treatment)]
A flat packaging bag was produced using the barrier laminate obtained above. The size of the flat packaging bag is B5 size (182 mm×257 mm). The flat packaging bag is filled with 150 mL of water.

The flat packaging bag was boiled in hot water at 95°C for 30 minutes. A barrier laminate was cut out from a flat packaging bag to obtain a test piece. Using this test piece, the oxygen permeability and water vapor permeability were measured in the same manner as described above.

The flat packaging bag was retorted with hot water at 121° C. for 30 minutes. A barrier laminate was cut out from a flat packaging bag to obtain a test piece. Using this test piece, the oxygen permeability and water vapor permeability were measured in the same manner as described above.

[Gas barrier property evaluation (after gelboflex test)]
A four-sided bag was produced using the two barrier laminates obtained above. The size of this bag is A4 size (210 mm×297 mm). Using this bag, the gelboflex test (stroke: 80 mm, bending motion: 400°) based on ASTM F392 was repeated 10 times. After that, the barrier laminate was cut out from the bag to obtain a test piece. Using this test piece, the oxygen permeability and water vapor permeability were measured in the same manner as described above.

[Gas barrier property evaluation (boiling or retort treatment and after Gelboflex test)]
A four-sided bag was produced using the two barrier laminates obtained above. The size of this bag is A4 size (210 mm×297 mm). The inside of the bag is filled with 400 mL of water. The four-sided bag was boiled or retorted under the above conditions. Water was removed from the four-sided bag, and using this bag, the gelboflex test (stroke: 80 mm, bending motion: 400°) in accordance with ASTM F392 was repeated 10 times. After that, the barrier laminate was cut out from the bag to obtain a test piece. Using this test piece, the oxygen permeability and water vapor permeability were measured in the same manner as described above.

[Measurement of heat shrinkage]
The barrier laminate obtained above was cut into a size of 10 cm×10 cm to obtain a test piece. The test piece was placed in an oven and heated at 120° C. for 15 minutes or 150° C. for 5 minutes. The lengths in the MD direction and the TD direction of the test piece before and after heating in the oven were measured with a glass scale. Based on the following formula, the thermal shrinkage rate (MD) in the MD direction and the thermal shrinkage rate (TD) in the TD direction were calculated. Table 1 lists the average thermal shrinkage for the two specimens.

Thermal shrinkage (MD) (%) = (length in MD direction of laminate before heat treatment - length in MD direction of laminate after heat treatment)/length in MD direction of laminate before heat treatment ×100
Thermal shrinkage (TD) (%) = (length in the TD direction of the laminate before heat treatment - length in the TD direction of the laminate after heat treatment) / length in the TD direction of the laminate before heat treatment ×100

1: barrier laminate, 10: polypropylene resin substrate, 20: barrier substrate, 22: polypropylene resin layer, 23: surface coat layer or surface resin layer, 24: deposited film, 25: barrier coat layer, 30: Sealant layer, 40A, 40B: adhesive layer,
50: packaging bag, 51: easy-to-open portion, 52: notch portion, 53: half-cut line,
60: Standing pouch, 61: Body (side sheet), 62: Bottom (bottom sheet), 63: Vapor release mechanism, 63a: Vapor release seal part, 63b: Non-seal part,
A: Vacuum vessel, B: Unwinding unit, C: Film forming drum, D: Winding unit, E: Transport roll, F: Evaporation source, G: Reactive gas supply unit, H: Deposition prevention box, I: Evaporation Material, J: Plasma gun, S: Substrate, A1: Vacuum vessel, B1: Unwinding unit, C1: Cooling/electrode drum, D1: Winding unit, E1: Conveyor roll, F1: Glow discharge plasma, G1: Reaction gas supply unit, H1: raw material supply nozzle, I1: raw material gas supply unit, J1: magnet, K1: power source, L1: vacuum pump

Claims (17)

a substrate;
an adhesive layer;
A barrier laminate comprising a sealant layer and a sealant layer in this order in the thickness direction,
The base material is a barrier base material comprising a polypropylene resin layer and a deposited film,
The polypropylene resin layer is a layer subjected to stretching treatment,
The deposited film is composed of an inorganic oxide,
The adhesive layer is a layer having a thickness of 2 μm or less,
The residual solvent amount in the barrier laminate is 10 mg/m ² or less.
Barrier laminate. a first substrate;
a first adhesive layer;
a second substrate;
a second adhesive layer;
A barrier laminate comprising a sealant layer and a sealant layer in this order in the thickness direction,
Either one of the first base material and the second base material is a barrier base material comprising a polypropylene resin layer and a deposited film, and the other of the first base material and the second base material. is a polypropylene resin base material,
The polypropylene resin layer is a layer subjected to stretching treatment,
The deposited film is composed of an inorganic oxide,
The polypropylene resin base material is a base material subjected to stretching treatment,
Each of the first adhesive layer and the second adhesive layer is a layer having a thickness of 2 μm or less,
The residual solvent amount in the barrier laminate is 10 mg/m ² or less.
Barrier laminate. 3. The barrier laminate according to claim 1, wherein the adhesive layer is a layer formed from a non-solvent adhesive. The solvent-free adhesive is a two-component curing adhesive containing a main agent and a curing agent, and the polymer component contained in the main agent has a weight average molecular weight (Mw) of 800 or more and 10,000 or less. 4. The barrier laminate according to claim 3. The solvent-free adhesive is a two-component curing adhesive containing a main agent and a curing agent, and the polymer component contained in the main agent has a polydispersity (Mw/Mn) of 2.8 or less. , The barrier laminate according to claim 3 or 4. When the first base material is the barrier base material, the vapor-deposited film faces the sealant layer side, and the polypropylene resin layer faces the side opposite to the sealant layer. materials are placed,
When the second base material is the barrier base material, the vapor-deposited film faces the first base material side, and the polypropylene resin layer faces the sealant layer side. materials are placed
The barrier laminate according to claim 2. The first base material is the polypropylene resin base material,
wherein the second substrate is the barrier substrate,
The barrier laminate according to claim 2 or 6. 8. The barrier base material further comprises a surface coat layer between the polypropylene resin layer and the deposited film, and the surface coat layer contains a resin material having a polar group. The barrier laminate according to item 1 or 1. Claims 1 to 1, wherein the barrier substrate further comprises a surface resin layer between the polypropylene resin layer and the deposited film, and the surface resin layer contains a resin material having a melting point of 180°C or higher. 8. The barrier laminate according to any one of 7. 10. The barrier laminate according to claim 9, wherein the polypropylene resin layer and the surface resin layer in the barrier substrate are co-extruded stretched resin films. The barrier laminate according to any one of claims 1 to 10, further comprising a barrier coat layer on the deposited film. The barrier laminate according to any one of Claims 1 to 11, wherein the sealant layer is a resin layer made of polypropylene. The barrier laminate according to any one of claims 1 to 12, which is used for packaging containers. A packaging container comprising the barrier laminate according to any one of claims 1 to 13. The packaging container according to claim 14, which is a boil or retort pouch. A lid material comprising the barrier laminate according to any one of claims 1 to 13. A packaging container comprising: a container body having an accommodating portion; and the lid member according to claim 16 joined to the container body so as to seal the accommodating portion.

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