JP2020157515A - Laminate and packaging bag - Google Patents

Abstract

To provide a laminate that enables production of a packaging bag which has sufficient strength and heat resistance and is excellent in recyclability and gas barrier property.SOLUTION: A laminate includes a base material and a sealant layer, in which the base material and the sealant layer are composed of the same material, the base material is subjected to at least one of stretching treatment and electron beam irradiation treatment, the same material is polyethylene or polypropylene, and a barrier coat layer is provided between the base material and the sealant layer.SELECTED DRAWING: Figure 1

Description

The present invention relates to a laminate used for manufacturing a packaging bag or the like. The present invention also relates to a packaging bag made of the laminate.

Conventionally, a resin film made of a resin material has been used as a material for forming a packaging bag. For example, a resin film composed of polyolefin is widely used in packaging bags because it has appropriate flexibility and transparency and is excellent in heat sealability.

Normally, a resin film made of polyolefin is inferior in strength and heat resistance, so it cannot be used as a base material for making packaging bags, etc., and is attached to a resin film made of polyester, polyamide, etc. Therefore, a normal packaging bag is composed of a laminate in which a base material and a sealant layer are made of different kinds of resin materials (for example, Patent Document 1).

In recent years, with the growing demand for the construction of a recycling-oriented society, packaging bags and the like are required to be highly recyclable. However, the conventional packaging bag is composed of different types of resin materials as described above, and it is difficult to separate each resin material, so that the packaging bag is not recycled at present.

Japanese Unexamined Patent Publication No. 2009-202519

The present inventors can significantly improve the strength and heat resistance of a polyethylene film or a polypropylene film by subjecting it to at least one of stretching treatment and electron beam irradiation treatment, and it is used for manufacturing packaging bags and the like. It was found that it can be used as a base material for a laminate. Then, it was found that the recyclability of the laminate can be remarkably improved by forming the sealant layer from polyolefin as in the case of the base material.
Furthermore, the present inventors have significantly improved the oxygen barrier property and the water vapor barrier property (gas barrier property) of the contents to be filled in the packaging bag produced by using the laminate of the present invention by further providing the barrier coat layer. It was found that it can be improved.

The present invention has been made in view of the above findings, and the problem to be solved is that it is possible to manufacture a packaging bag having sufficient strength and heat resistance, and also excellent in recyclability and gas barrier property. Is to provide a laminate.

Another problem to be solved by the present invention is to provide a packaging bag made of the laminate.

The laminate of the present invention comprises a base material and a sealant layer.
The substrate and sealant layer are made of the same material
The base material is subjected to at least one of stretching treatment and electron beam irradiation treatment.
The same material is polyethylene or polypropylene,
A barrier coat layer is provided between the base material and the sealant layer.

In one embodiment, the barrier coat layer contains at least one metal alkoxide hydrolyzate or a metal alkoxide hydrolyzate obtained by polycondensing a mixture of a metal alkoxide and a water-soluble polymer by a sol-gel method. It is a gas barrier coating film.

In one embodiment, the thickness of the barrier coat layer is 0.01 μm or more and 100 μm or less.

In one embodiment, a thin film is provided between the substrate and the barrier coat layer, or between the barrier coat layer and the sealant layer.

In one embodiment, the vapor deposition film is composed of an inorganic oxide.

In one embodiment, the laminate is used for packaging bags.

The packaging bag of the present invention is characterized by being composed of the above-mentioned laminate.

In one embodiment, the packaging bag comprises a spout.

According to the present invention, it is possible to provide a laminate capable of producing a packaging bag or the like having sufficient strength and heat resistance and also excellent in recyclability and gas barrier property.

It is sectional drawing which shows one Embodiment of the laminated body of this invention. It is sectional drawing which shows one Embodiment of the laminated body of this invention. It is sectional drawing which shows one Embodiment of the laminated body of this invention. It is a perspective view which shows one Embodiment of the packaging bag produced using the laminated body of this invention. It is a front view which shows one Embodiment of the packaging bag produced using the laminated body of this invention. It is a front view which shows one Embodiment of the packaging bag produced using the laminated body of this invention.

(Laminated body)
As shown in FIG. 1, the laminate 10 of the present invention is characterized by including a base material 11 and a sealant layer 12.
In one embodiment, the laminate 10 includes a barrier coat layer 13 between the base material 11 and the sealant layer 12, as shown in FIG.
Further, in one embodiment, the laminate 10 includes a vapor-deposited film between the base material and the barrier coat layer, or between the barrier coat layer and the sealant layer (not shown).
Further, in one embodiment, as shown in FIG. 2, the laminated body 10 includes a light-shielding printing layer 14 between the barrier coat layer 13 and the sealant layer 12.
Further, in one embodiment, the sealant 12 included in the laminate 10 includes a light-shielding layer 15 as shown in FIG. Further, in the present embodiment, the sealant layer 12 can include a laminate layer 16 and a heat seal layer 17.
In the present invention, the base material and the sealant layer are made of the same material, that is, polyethylene or polypropylene, whereby the recyclability of the laminate can be improved.

In addition, the laminate of the present invention may be provided with an adhesive layer between any layers, for example, between the barrier coat layer and the sealant layer (not shown).
Further, the laminate of the present invention may include an intermediate layer between the base material and the sealant layer (not shown).

(Base material)
The base material constituting the laminate of the present invention is made of polyethylene or polypropylene, and is characterized in that at least one of stretching treatment and electron beam irradiation treatment is applied.
By performing the stretching treatment and the electron beam irradiation treatment, the heat resistance and strength of the base material can be remarkably improved, and the physical properties required as an outer layer of a packaging bag or the like can be satisfied.
When the base material is subjected to the electron beam irradiation treatment, the base material is provided so that the electron beam irradiation surface of the base material is the outermost surface of the laminate.

As the polyethylene, high density polyethylene, medium density polyethylene, low density polyethylene, linear low density polyethylene and ultra low density polyethylene can be used.
Among these, high-density polyethylene and medium-density polyethylene are preferable from the viewpoint of strength and heat resistance of the base material, and medium-density polyethylene is more preferable from the viewpoint of stretchability.

In the present invention, as the high-density polyethylene, polyethylene having a density of 0.945 g / cm ³ or more can be used, and as a medium-density polyethylene, a density of 0.925 g / cm ³ or more and less than 0.945 g / cm ³ can be used. As the low-density polyethylene, polyethylene having a density of 0.900 g / cm ³ or more and less than 0.925 g / cm ³ can be used, and as a linear low-density polyethylene, the density Polyethylene having a density of 0.900 g / cm ³ or more and less than 0.925 g / cm ³ can be used, and as the ultra-low density polyethylene, polyethylene having a density of less than 0.900 g / cm ³ can be used.

Further, a copolymer of ethylene and another monomer can be used as the polyethylene as long as the characteristics of the present invention are not impaired. Examples of the ethylene copolymer include a copolymer composed of ethylene and an α-olefin having 3 to 20 carbon atoms, and examples of the α-olefin having 3 to 20 carbon atoms include propylene, 1-butene and 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 and the like. Further, as long as the object of the present invention is not impaired, it may be a copolymer with vinyl acetate, acrylic acid ester or the like.

Further, in the present invention, the base material preferably contains polyethylene derived from biomass. Biomass-derived polyethylene uses biomass-derived ethylene as a raw material instead of ethylene obtained from fossil fuels. Since such biomass-derived polyethylene is a carbon-neutral material, it is possible to reduce the environmental load of producing the laminate. Such biomass-derived polyethylene can be produced, for example, by a method as described in JP2013-177531A. Further, commercially available biomass-derived polyethylene (for example, green PE commercially available from Braskem) may be used.

It is also possible to use polyethylene recycled by mechanical recycling. Here, mechanical recycling generally refers to crushing a recovered polyethylene film or the like, alkaline cleaning to remove stains and foreign substances on the film surface, and then drying the film under high temperature and reduced pressure for a certain period of time to stay inside the film. This is a method of diffusing pollutants, decontaminating, removing stains on a film made of polyethylene, and returning the film to polyethylene.

When the packaging bag produced by the laminate of the present invention is filled with the contents and subjected to retort treatment, the base material and the sealant layer are preferably made of polypropylene from the viewpoint of retort treatment suitability.
Polypropylene may be a homopolymer, a random copolymer or a block copolymer.
The polypropylene homopolymer is a polymer containing only propylene, and the polypropylene random copolymer is a polymer of propylene and other α-olefins other than propylene (for example, ethylene, butene-1, 4-methyl-1-pentene, etc.). It is a random copolymer, and the polypropylene block copolymer is a copolymer having a polymer block made of propylene and a polymer block made of α-olefin other than the above-mentioned propylene.
Among these polypropylenes, homopolymers or randoms can be used from the viewpoint of improving the transparency of the base material and improving the visibility when an image is formed on the surface of the base material on the adhesive layer side. It is preferable to use a copolymer. A homopolymer can be used when the rigidity and heat resistance of the packaging bag are important, and a random copolymer can be used when the impact resistance and the like are important.

It is also possible to use polypropylene derived from biomass or polypropylene recycled by mechanical recycling.

The base material can contain additives as long as the properties of the present invention are not impaired, and for example, a cross-linking agent, an antioxidant, an anti-blocking agent, a slip agent, an ultraviolet absorber, a light stabilizer, and a filling. Examples include agents, reinforcing agents, antistatic agents, pigments and modifying resins.

The base material may have a single-layer structure or may have a multi-layer structure.
In one embodiment, the base material is a layer composed of high-density polyethylene (hereinafter referred to as high-density polyethylene layer), a layer composed of medium-density polyethylene (hereinafter referred to as medium-density polyethylene layer), and high-density polyethylene. It has a multi-layer structure including a layer composed of (hereinafter referred to as a high-density polyethylene layer).
With such a configuration, the strength and heat resistance of the base material can be further improved. In addition, it is possible to prevent the occurrence of curl on the base material. It is also possible to improve the stretchability of the base material.
At this time, the thickness of the high-density polyethylene layer is preferably thinner than the thickness of the medium-density polyethylene layer.
The ratio of the thickness of the high-density polyethylene layer to the thickness of the medium-density polyethylene layer is preferably 1/10 or more and 1/1, and more preferably 1/5 or more and 1/2 or less.
By setting the ratio of the thickness of the high-density polyethylene layer to the thickness of the medium-density polyethylene layer to 1/10 or more, the strength and heat resistance of the base material can be further improved. Further, by setting the ratio of the thickness of the high-density polyethylene layer to the thickness of the medium-density polyethylene layer to 1/1 or less, the stretchability of the base material can be further improved.

In one embodiment, the substrate is a high density polyethylene layer, a medium density polyethylene layer, a low density polyethylene layer, a linear low density polyethylene layer or an ultralow density polyethylene layer (in this paragraph, for simplification of description). , Collectively referred to as a low-density polyethylene layer), a medium-density polyethylene layer, and a high-density polyethylene layer.
With such a configuration, the stretchability of the base material can be improved. In addition, the strength and heat resistance of the base material can be improved. In addition, it is possible to prevent the occurrence of curl on the base material. Further, the production efficiency of the base material can be improved.
At this time, the thickness of the high-density polyethylene layer is preferably thinner than the thickness of the medium-density polyethylene layer.
The ratio of the thickness of the high-density polyethylene layer to the thickness of the medium-density polyethylene layer is preferably 1/10 or more and 1/1, and more preferably 1/5 or more and 1/2 or less.
By setting the ratio of the thickness of the high-density polyethylene layer to the thickness of the medium-density polyethylene layer to 1/10 or more, the strength and heat resistance of the base material can be improved. Further, by setting the ratio of the thickness of the high-density polyethylene layer to the thickness of the medium-density polyethylene layer to 1/1 or less, the stretchability of the base material can be improved.
Further, the thickness of the high-density polyethylene layer is preferably the same as the thickness of the low-density polyethylene layer or thicker than the thickness of the low-density polyethylene.
The ratio of the thickness of the high-density polyethylene layer to the thickness of the low-density polyethylene layer is preferably 1 / 0.25 or more and 1/2 or less, and more preferably 1 / 0.5 or more and 1/1 or less. preferable.
By setting the ratio of the thickness of the high-density polyethylene layer to the thickness of the low-density polyethylene layer to 1/0.25 or more, the heat resistance of the base material can be improved. Further, by setting the ratio of the thickness of the high-density polyethylene layer to the thickness of the low-density polyethylene layer to 1/1 or less, the adhesion between the medium-density polyethylene layers can be improved.
The thickness of each high-density polyethylene layer is preferably 1 μm or more and 20 μm or less, and more preferably 2 μm or more and 10 μm or less. By setting the thickness of the high-density polyethylene layer to 1 μm or more, the strength and heat resistance of the laminate of the present invention can be further improved. Further, by setting the thickness of the high-density polyethylene layer to 20 μm or less, the processability of the laminate of the present invention can be further improved.
The thickness of the medium-density polyethylene layer is preferably 1 μm or more and 30 μm or less, and more preferably 5 μm or more and 20 μm or less. By setting the thickness of the medium-density polyethylene layer to 1 μm or more, the stretchability of the film can be further improved. Further, by setting the thickness of the medium-density polyethylene layer to 30 μm or less, the processability of the laminate of the present invention can be further improved.
The thickness of the low-density polyethylene layer is preferably 1 μm or more and 10 μm or less, and more preferably 2 μm or more and 5 μm or less. By setting the thickness of the low-density polyethylene layer to 1 μm or more, the adhesion between the high-density polyethylene layer and the medium-density polyethylene layer can be further improved. Further, by setting the thickness of the low-density polyethylene layer to 5 μm or less, the processability of the laminate of the present invention can be further improved.
In one embodiment, a substrate having such a configuration can be produced, for example, by an inflation method.
Specifically, from the outside, the high-density polyethylene, the medium-density polyethylene layer, and the low-density polyethylene layer, the linear low-density polyethylene layer, or the ultra-low-density polyethylene layer are co-extruded in a tubular shape and then opposed to each other. It can be produced by crimping a low-density polyethylene layer, a linear low-density polyethylene layer, or an ultra-low-density polyethylene layer with each other with a rubber roll or the like.
By manufacturing by such a method, the number of defective products in manufacturing can be remarkably reduced, and finally, the production efficiency can be improved.
Further, in the inflation film forming machine, stretching can also be performed, whereby the production efficiency can be further improved.

In one embodiment, from the outside, a high density polyethylene layer, a blended resin layer of high density polyethylene and medium density polyethylene, a medium density polyethylene layer, a low density polyethylene layer, a linear low density polyethylene layer or an ultra low density polyethylene. From a layer (in the same paragraph, collectively referred to as a low density polyethylene layer for simplicity), a medium density polyethylene layer, a blended resin layer of high density polyethylene and medium density polyethylene, and a high density polyethylene layer. It can also be configured as a seven-layer co-pressed film.
With such a configuration, the adhesion between the high-density polyethylene layer and the medium-density polyethylene layer can be improved. In addition, the processability of the laminate of the present invention can be improved.
The thickness of each high-density polyethylene layer is preferably 1 μm or more and 20 μm or less, and more preferably 2 μm or more and 10 μm or less. By setting the thickness of the high-density polyethylene layer to 1 μm or more, the strength and heat resistance of the laminate of the present invention can be further improved. Further, by setting the thickness of the high-density polyethylene layer to 20 μm or less, the processability of the laminate of the present invention can be further improved.
The thickness of the blend resin layer of each high-density polyethylene and medium-density polyethylene is preferably 1 μm or more and 20 μm or less, and more preferably 2 μm or more and 10 μm or less. As a result, the adhesion between the high-density polyethylene layer and the medium-density polyethylene layer can be improved. In addition, the processability of the laminate of the present invention can be improved.
The thickness of the medium-density polyethylene layer is preferably 1 μm or more and 30 μm or less, and more preferably 5 μm or more and 20 μm or less. By setting the thickness of the medium-density polyethylene layer to 1 μm or more, the stretchability of the film can be further improved. Further, by setting the thickness of the medium-density polyethylene layer to 30 μm or less, the processability of the laminate of the present invention can be further improved.
The thickness of the low-density polyethylene layer is preferably 1 μm or more and 10 μm or less, and more preferably 2 μm or more and 5 μm or less.
By setting the thickness of the low-density polyethylene layer to 1 μm or more, the adhesion between the high-density polyethylene layer and the medium-density polyethylene layer can be further improved. Further, by setting the thickness of the low-density polyethylene layer to 5 μm or less, the processability of the laminate of the present invention can be further improved.
In one embodiment, the stretched polyethylene film having such a structure can be produced by the inflation method described above.
By manufacturing by such a method, the number of defective products in manufacturing can be remarkably reduced, and finally, the production efficiency can be improved.
Further, in the inflation film forming machine, stretching can also be performed, whereby the production efficiency can be further improved.

When the base material has been subjected to a stretching treatment, the stretching may be uniaxial stretching or biaxial stretching.
The stretching ratio in the longitudinal direction (MD) of the base material is preferably 2 times or more and 10 times or less, and preferably 3 times or more and 7 times or less.
The strength and heat resistance of the base material can be improved by setting the draw ratio in the longitudinal direction (MD) of the base material to 2 times or more. Further, the printability on the base material can be improved. In addition, the transparency of the base material can be improved. On the other hand, the upper limit of the draw ratio in the longitudinal direction (MD) of the base material is not particularly limited, but is preferably 10 times or less from the viewpoint of the breaking limit of the base material.
Further, the stretching ratio in the lateral direction (TD) of the base material is preferably 2 times or more and 10 times or less, and preferably 3 times or more and 7 times or less.
By setting the stretching ratio of the base material in the lateral direction (TD) to 2 times or more, the strength and heat resistance of the base material can be improved. Further, the printability on the base material can be improved. In addition, the transparency of the base material can be improved. On the other hand, the upper limit of the stretching ratio in the lateral direction (TD) of the base material is not particularly limited, but is preferably 10 times or less from the viewpoint of the breaking limit of the base material.

When the base material is irradiated with electron beams, the crosslink density of polyethylene or polypropylene contained in the base material can be improved by the electron beam irradiation, and the heat resistance and strength of the base material can be significantly improved. .. It should be noted that this aspect is particularly suitable when the base material is made of polyethylene.

The base material may be polyethylene on one surface whose crosslink density has been improved by electron beam irradiation, or may have an overall improved crosslink density of polyolefin.
Further, when the base material has a multilayer structure, it is sufficient that the crosslink density of polyethylene in the outermost layer is at least improved by electron beam irradiation.
From the viewpoint of strength and heat resistance, it is preferable that the cross-linked density of polyethylene as a whole is improved by electron beam irradiation.

As a device that can be used for irradiating the base material with an electron beam, a conventionally known device can be used, for example, a curtain type electron irradiating device (LB1023, manufactured by Eye Electron Beam Co., Ltd.), a line irradiation type low energy. An electron beam irradiator (EB-ENGINE, manufactured by Hamamatsu Photonics Co., Ltd.) and a drum roll type electron beam irradiator (EZ-CURE, manufactured by I Electron Beam Co., Ltd.) can be preferably used.

The dose of the electron beam irradiated to the substrate is preferably in the range of 10 kGy or more and 2000 kGy or less, more preferably in the range of 20 kGy or more and 1000 kGy or less, and more preferably in the range of 150 kGy or more and 500 kGy or less.
The accelerating voltage of the electron beam is preferably in the range of 30 kV or more and 300 kV or less, more preferably in the range of 50 kV or more and 300 kV or less, and further preferably in the range of 50 kV or more and 250 kV or less.
The irradiation energy of the electron beam is preferably in the range of 20 keV or more and 750 keV or less, more preferably in the range of 25 keV or more and 500 keV or less, further preferably in the range of 30 keV or more and 400 keV or less, and more preferably 20 keV or more and 200 keV or less. The following range is particularly preferable.

The oxygen concentration in the electron beam irradiator is preferably 500 ppm or less, more preferably 100 ppm or less. By performing electron beam irradiation under such conditions, it is possible to suppress the generation of ozone and suppress the radicals generated by electron beam irradiation from being inactivated by oxygen in the atmosphere. it can. Such conditions can be achieved, for example, by creating an atmosphere of an inert gas (nitrogen, argon, etc.) in the apparatus.

In one embodiment, the electron beam irradiation can be performed at the same time as cooling by using a cooling drum or the like.

Further, the base material may be surface-treated. As a result, the adhesion to the adjacent layer can be improved.
The surface treatment method is not particularly limited, and for example, corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and / or nitrogen gas, physical treatment such as glow discharge treatment, and oxidation using chemicals. Examples include chemical treatment such as treatment.
Further, an anchor coat layer may be formed on the surface of the base material by using a conventionally known anchor coat agent.

The base material may have a printing layer on its surface, and the image formed on the printing layer is not particularly limited, and characters, patterns, symbols, combinations thereof, and the like are represented.
From the viewpoint of environmental load, it is preferable that the printing layer is formed on the substrate by using an ink derived from biomass.
The method for forming the print layer is not particularly limited, and examples thereof include conventionally known printing methods such as a gravure printing method, an offset printing method, and a flexographic printing method. Among these, the flexographic printing method is preferable from the viewpoint of environmental load.

The thickness of the base material is preferably 10 μm or more and 50 μm or less, and more preferably 15 μm or more and 30 μm or less. By setting the thickness of the base material to 10 μm or more, its strength and heat resistance can be further improved. Further, by setting the thickness of the base material to 50 μm or less, the processability of the laminate provided with the base material can be improved.

The base material can be prepared by forming a film of a resin composition containing at least polyethylene or polypropylene by using a T-die method, an inflation method, or the like to obtain a resin film, and then stretching and / or irradiating with an electron beam. it can.
By forming a film by the inflation method, the resin film can be stretched at the same time.
When both the stretching of the resin film and the electron beam irradiation are performed, either of them may be performed first, but it is preferable to perform the stretching first because of the suitability for stretching.

When the base material is produced by the T-die method, the MFR of the resin composition is preferably 3 g / 10 minutes or more and 20 g / 10 minutes or less.
By setting the MFR of the resin composition to 3 g / 10 minutes or more, the processability of the base material can be improved. Further, by setting the MFR of the resin composition to 20 g / 10 minutes or less, it is possible to prevent the base material from breaking during stretching.

When the base material is produced by the inflation method, the MFR of the resin composition is preferably 0.5 g / 10 minutes or more and 5 g / 10 minutes or less.
By setting the MFR of the resin composition to 0.5 g / 10 minutes or more, the processability of the base material can be improved. Further, by setting the MFR of the resin composition to 5 g / 10 minutes or less, the film-forming property can be improved.

(Sealant layer)
In one embodiment, the sealant layer is characterized by being composed of the same material as the substrate, ie polyethylene or polypropylene. Thereby, the recyclability of the laminated body can be improved.

From the viewpoint of heat-sealing property, the sealant layer preferably contains polyethylene, and more preferably contains low-density polyethylene, linear low-density polyethylene, and ultra-low-density polyethylene.
Further, in order to improve the tearability of the packaging bag produced by using the laminate of the present invention, the sealant layer preferably contains low density polyethylene.
Further, in order to improve the drop strength of the packaging bag produced by using the laminate of the present invention, the sealant layer preferably contains linear low-density polyethylene. Examples of the linear low density polyethylene include C-4LLDPE and C-6LLDPE. From the viewpoint of the balance between tearability and impact resistance, C-4LLDPE is preferable, and from the viewpoint of improving drop resistance, C-6LLDPE is preferable.
The sealant layer preferably contains both C-4LLDPE and C-6LLDPE.

When the sealant layer contains low-density polyethylene and linear low-density polyethylene, the content of the low-density polyethylene is preferably 5% by mass or more and 20% by mass or less, and 9% by mass or more and 15% by mass or less. Is more preferable. By setting the content of the low-density polyethylene to 5% by mass or more, the tearability of the packaging bag produced by using the laminate of the present invention can be further improved. By setting the content of the low-density polyethylene to 20% by mass or less, the drop strength of the packaging bag produced by using the laminate of the present invention can be maintained.
The content of the linear low-density polyethylene is preferably 65% by mass or more and 90% by mass or less, and more preferably 70% by mass or more and 80% by mass or less. By setting the content of the linear low-density polyethylene to 65% by mass or more, the drop strength of the packaging bag produced by using the laminate of the present invention can be further improved. By setting the content of the linear low-density polyethylene to 90% by mass or less, additives such as a slip agent and an anti-blocking agent can be added, and a film having excellent processability can be obtained.

The sealant layer may also contain the above-mentioned biomass-derived polyethylene, mechanically recycled polyethylene, polypropylene and the like.

The sealant layer may contain the above additives as long as the characteristics of the present invention are not impaired.

In one embodiment, the sealant layer comprises a light-shielding layer containing a light-shielding pigment, along with polyethylene or polypropylene. Thereby, the storage stability of the contents filled in the packaging bag produced by the laminate of the present invention can be improved. The light-shielding layer may have a single-layer structure or a multi-layer structure.

Examples of the light-shielding pigment include carbon black, acetylene black, lamp black, black smoke, iron black, aniline black, titanium oxide, barium oxide, calcium carbonate, aluminum hydroxide and zinc oxide.
By using these light-shielding pigments, it is possible to conceal the contents to be filled in the packaging bag produced by the laminate of the present invention.
Further, by using a white pigment such as titanium oxide, the sealant layer can be provided with a function as a background layer, and the visibility of an image formed on the base material can be improved.

The content of the light-shielding pigment in the light-shielding layer is preferably 2% by mass or more and 25% by mass or less, and more preferably 4% by mass or more and 23% by mass or less. This makes it possible to further improve the storage stability of the contents packed in the packaging bag produced by the laminate of the present invention while maintaining the heat-sealing property of the heat-sealing layer.

The thickness of the light-shielding layer is preferably 10 μm or more and 60 μm or less, and more preferably 15 μm or more and 40 μm or less. Thereby, the storage stability of the contents filled in the packaging bag produced by the laminate of the present invention can be further improved.

The sealant layer may have a single layer structure or may have a multi-layer structure. For example, it is composed of a laminate layer laminated with a base material, an intermediate layer, and a heat seal layer.
When the sealant layer includes a light-shielding layer, it is preferably provided as an intermediate layer. As a result, the light-shielding property can be improved without deteriorating the heat-sealing property and the laminate property with the base material.

In one embodiment, the interlayer provided by the multi-layered sealant layer comprises at least one of medium density polyethylene and high density polyethylene. Thereby, the strength of the laminated body of the present invention can be further improved.
Specific examples of the layer containing at least one of medium density polyethylene and high density polyethylene as the intermediate layer include a layer containing at least one of low density polyethylene, linear low density polyethylene, and ultra low density polyethylene, and medium density. A configuration comprising a layer containing at least one of polyethylene and high density polyethylene and a layer containing at least one of low density polyethylene, linear low density polyethylene, and ultra low density polyethylene.
With the above configuration, it is possible to further improve the bag-making suitability and strength of the laminate of the present invention while maintaining the heat-sealing property.

The thickness of the sealant layer is preferably 40 μm or more and 150 μm or less, and more preferably 60 μm or more and 100 μm or less. Thereby, the heat-sealing property of the laminated body of the present invention can be further improved.

(Barrier coat layer)
The laminate of the present invention is characterized by providing a barrier coat layer between the base material and the sealant layer. Thereby, the oxygen barrier property and the water vapor barrier property of the laminated body can be improved.

In one embodiment, the barrier coat layer is a hydrolysis of a metal alkoxide obtained by polycondensing a mixture of a metal alkoxide and a water-soluble polymer by a sol-gel method in the presence of a sol-gel method catalyst, water, an organic solvent and the like. A gas barrier coating film containing at least one resin composition such as a product or a hydrolyzed condensate of a metal alkoxide.
When the laminate of the present invention includes a thin-film deposition film composed of an inorganic oxide, the barrier coat layer of this form is provided adjacent to the thin-film deposition film to effectively prevent the occurrence of cracks in the vapor-film deposition film. can do.

In one embodiment, the metal alkoxide is represented by the following general formula.
R ¹ _n M (OR ² ) _m
(However, in the formula, R ¹ and R ² each 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 represents an integer of 1 or more. , N + m represents the valence of M.)

As the metal atom M, for example, silicon, zirconium, titanium, aluminum and the like can be used.
Examples of the organic group represented by R ¹ and R ² include alkyl groups such as methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group and i-butyl group. Can be done.

Examples of the metal alkoxide satisfying the above general formula include tetramethoxysilane (Si (OCH ₃ ) ₄ ), tetraethoxysilane (mass%) Si (OC ₂ H ₅ ) ₄ ), and tetrapropoxysilane (Si (OC ₃ H)). ₇ ) ₄ ), tetrabutoxysilane (Si (OC ₄ H ₉ ) ₄ ) and the like can be mentioned.

Further, it is preferable to use a silane coupling agent together with the above metal alkoxide.
As the silane coupling agent, known organic reactive group-containing organoalkoxysilanes can be used, but organoalkoxysilanes having an epoxy group are particularly preferable. Examples of the organoalkoxysilane having an epoxy group include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. Be done.

Two or more kinds of the above-mentioned silane coupling agent may be used, and the silane coupling agent is used within the range of about 1 to 20 parts by mass with respect to 100 parts by mass of the total amount of the above-mentioned alkoxide. Is preferable.

As the water-soluble polymer, polyvinyl alcohol and ethylene-vinyl alcohol copolymer are preferable, and from the viewpoint of oxygen barrier property, water vapor barrier property, water resistance and weather resistance, it is preferable to use these in combination.

The content of the water-soluble polymer in the gas barrier coating film 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.
By setting the content of the water-soluble polymer in the gas barrier coating film to 5 parts by mass or more with respect to 100 parts by mass of the metal alkoxide, the oxygen barrier property and the water vapor barrier property of the laminate can be further improved. Further, by setting the content of the water-soluble polymer in the gas barrier coating film to 500 parts by mass or less with respect to 100 parts by mass of the metal alkoxide, the film forming property of the gas barrier coating film can be improved.

The thickness of the gas barrier coating film is preferably 0.01 μm or more and 100 μm or less, and more preferably 0.1 μm or more and 50 μm or less. Thereby, the oxygen barrier property and the water vapor barrier property can be further improved while maintaining the recyclability.
By setting the thickness of the gas barrier coating film to 0.01 μm or more, the oxygen barrier property and the water vapor barrier property of the laminated body can be improved. Further, when it is provided adjacent to the thin-film deposition film composed of an inorganic oxide, it is possible to prevent the occurrence of cracks in the thin-film deposition film.

The gas barrier coating film is prepared by applying a composition containing the above materials by a conventionally known means such as a roll coating such as a gravure roll coater, a spray coating, a spin coating, dipping, a brush, a bar code, and an applicator, and the composition thereof. The product can be formed by polycondensing the product by the sol-gel method.
As the sol-gel method catalyst, an acid or amine compound is suitable. As the amine compound, a tertiary amine which is substantially insoluble in water and soluble in an organic solvent is preferable, and for example, N, N-dimethylbenzylamine, tripropylamine, tributylamine, and trypentyl are preferable. Amine and the like can be mentioned. Among these, N, N-dimethylbenzylamine is preferable.
The sol-gel method catalyst is preferably used in the range of 0.01 parts by mass or more and 1.0 parts by mass or less, and 0.03 parts by mass or more and 0.3 parts by mass or less per 100 parts by mass of the metal alkoxide. Is more preferable.
By setting the amount of the sol-gel method catalyst to be 0.01 part by mass or more per 100 parts by mass of the metal alkoxide, the catalytic effect can be improved. Further, by setting the amount of the sol-gel method catalyst to be 1.0 part by mass or less per 100 parts by mass of the metal alkoxide, the thickness of the formed gas barrier coating film can be made uniform.

The composition may further contain an acid. The acid is used as a catalyst for the sol-gel process, mainly as a catalyst for hydrolysis of alkoxides, silane coupling agents and the like.
As the acid, mineral acids such as sulfuric acid, hydrochloric acid and nitric acid, and organic acids such as acetic acid and tartaric acid are used. The amount of the acid used is preferably 0.001 mol or more and 0.05 mol or less with respect to the total molar amount of the alkoxide content (for example, the silicate portion) of the alkoxide and the silane coupling agent.
The catalytic effect can be improved by setting the amount of the acid to be 0.001 mol or more with respect to the total molar amount of the alkoxide content (for example, the silicate portion) of the alkoxide and the silane coupling agent. Further, the thickness of the gas barrier coating film formed can be made uniform by setting the total molar amount of the alkoxide and the silane coupling agent (for example, the silicate portion) to 0.05 mol or less. it can.

Further, the composition may contain water at a ratio of preferably 0.1 mol or more and 100 mol or less, more preferably 0.8 mol or more and 2 mol or less, based on 1 mol of the total molar amount of alkoxide. preferable.
By setting the water content to 0.1 mol or more with respect to 1 mol of the total molar amount of alkoxide, the oxygen barrier property and the water vapor barrier property of the laminate of the present invention can be improved. Further, by setting the water content to 100 mol or more with respect to 1 mol of the total molar amount of alkoxide, the hydrolysis reaction can be carried out rapidly.

Moreover, the said composition may contain an organic solvent. As the organic solvent, for example, methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butanol and the like can be used.

Hereinafter, an embodiment of a method for forming a gas barrier coating film will be described below.
First, a composition is prepared by mixing a metal alkoxide, a water-soluble polymer, a sol-gel method catalyst, water, an organic solvent and, if necessary, a silane coupling agent. The polycondensation reaction gradually proceeds in the composition.
Next, the composition is applied and dried on the substrate by the above-mentioned conventionally known method. By this drying, the polycondensation reaction of the alkoxide and the water-soluble polymer (and the silane coupling agent if the composition contains a silane coupling agent) further proceeds to form a layer of the composite polymer.
Finally, the gas barrier coating film can be formed by heating the composition at a temperature of 20 to 250 ° C., preferably 50 to 220 ° C. for 1 second to 10 minutes.

The print layer of the barrier coat layer may be formed. The method of forming the print layer and the like are as described above.

The barrier coat layer can contain the above additives as long as the characteristics of the present invention are not impaired.

(Embedded film)
In one embodiment, the laminate of the present invention may include a vapor deposition film between the substrate and the barrier coat layer, or between the barrier coat layer and the sealant layer. Thereby, the gas barrier property of the laminated body, specifically, the oxygen barrier property and the water vapor barrier property can be improved. In addition, it is possible to suppress a decrease in the mass of the contents filled in the packaging bag produced by using the laminate of the present invention.

The vapor-deposited film is composed of metals such as aluminum and inorganic oxides such as aluminum oxide, silicon oxide (silica), magsium oxide, calcium oxide, zirconium oxide, titanium oxide, boron oxide, hafnium oxide, and barium oxide. A vapor deposition film can be mentioned.

The thickness of the thin-film deposition film is preferably 1 nm or more and 150 nm or less, more preferably 5 nm or more and 60 nm or less, and further preferably 10 nm or more and 40 nm or less.
By setting the thickness of the thin-film deposition film to 1 nm or more, the oxygen barrier property and the water vapor barrier property of the laminated body can be further improved. Further, by setting the thickness of the thin-film deposition film to 150 nm or less, it is possible to prevent the occurrence of cracks in the thin-film deposition film. In addition, the recyclability of the laminate can be maintained.

The formation of the vapor deposition film on the substrate can be carried out by using a conventionally known method, for example, a physical vapor deposition method such as a vacuum vapor deposition method, a sputtering method and an ion plating method, PVD. (Method), and chemical vapor deposition methods (Chemical Vapor Deposition method, CVD method) such as plasma chemical vapor deposition method, thermochemical vapor deposition method, and photochemical vapor deposition method can be mentioned.

Further, for example, both the physical vapor deposition method and the chemical vapor deposition method can be used in combination to form a composite film composed of two or more layers of vapor-deposited films of different kinds of inorganic oxides. The degree of vacuum deposition chamber, before introduction of ^oxygen, preferably about 10 ^-2 to 10 -8 mbar, in the after introduction of ^oxygen, preferably about 10 ^-1 ~10 -6 mbar. The amount of oxygen introduced differs depending on the size of the vapor deposition machine and the like. As the oxygen to be introduced, an inert gas such as argon gas, helium gas, or nitrogen gas may be used as the carrier gas within a range that does not hinder. The transport speed of the film can be about 10 to 800 m / min.

The surface of the vapor-deposited film is preferably subjected to the above surface treatment. As a result, the adhesion to the adjacent layer can be improved.

(Light-shielding printing layer)
In one embodiment, the laminate of the present invention comprises a light-shielding printing layer between the barrier coat layer and the sealant layer. Thereby, the storage stability of the contents filled in the packaging bag produced by the laminate of the present invention can be improved.

The light-shielding printing layer contains light-shielding ink, and the color is not particularly limited, but may be appropriately changed depending on the contents such as black, white, gray, orange, red, yellow, silver and brown. preferable.
When the content contains vitamins, it is easily altered by light rays having a wavelength of 500 nm or less. Therefore, it is preferable to use an ink having a color that absorbs light rays having these wavelengths, for example, orange ink.
Further, as the light-shielding ink, an aluminum-containing ink or an ultraviolet curable ink can also be used.
The white light-shielding ink layer has a function as a background layer, and can improve the visibility of an image formed on the base material.

Examples of the light-shielding pigment that can be contained in the light-shielding ink include carbon black, acetylene black, lamp black, black smoke, iron black, aniline black, titanium oxide, zinc oxide, and the like, but are not limited thereto. Absent.

The light-shielding printing layer may have a multi-layer structure, for example, a configuration including a white ink layer and a gray ink layer, a configuration including a white ink layer and a black ink layer, a white ink layer and a yellow ink. Examples thereof include a configuration including a layer and a red ink layer, a configuration including a white ink layer and a silver ink layer, and the like.

The thickness of the light-shielding printing layer is preferably 0.2 μm or more and 8 μm or less, and more preferably 0.5 μm or more and 6 μm or less. By setting the thickness of the light-shielding printing layer to 0.2 μm or more, the storage stability of the contents filled in the packaging bag produced by the laminate of the present invention can be further improved. By setting the thickness of the light-shielding printing layer to 5 μm or less, a laminated body having stable physical properties can be obtained without impairing the adhesiveness with the sealant layer.

The method for forming the light-shielding printing layer is not particularly limited, and conventionally known printing methods such as an offset printing method and a flexographic printing method can be mentioned. Among these, the flexographic printing method is preferable from the viewpoint of environmental load.

(Adhesive layer)
The adhesive layer may be formed by a conventionally known adhesive. The adhesive may be a one-component curable type, a two-component curable type, or a non-curable type.
Further, the adhesive may be a solvent-free adhesive or a solvent-type adhesive, but from the viewpoint of environmental load, a solvent-free adhesive can be preferably used.
Examples of the solvent-free adhesive include polyether adhesives, polyester adhesives, silicone adhesives, epoxy adhesives and urethane adhesives, and among these, two-component curable urethanes. A system adhesive can be preferably used.
Examples of the solvent-based adhesive include rubber-based adhesives, vinyl-based adhesives, silicone-based adhesives, epoxy-based adhesives, phenol-based adhesives, and olefin-based adhesives.

When the laminate of the present invention includes an aluminum vapor deposition film, the adhesive layer provided adjacent to the aluminum vapor deposition film is made of a cured product of a resin composition containing a polyester polyol, an isocyanate compound, and a phosphoric acid-modified compound. Is preferable.
When the laminate provided with the vapor-deposited film is molded into a packaging bag, a bending load is applied to the laminate by a molding machine or the like, so that the aluminum vapor-deposited film may be cracked. By having the above-mentioned structure of the adhesive layer, it is possible to prevent the occurrence of cracks in the aluminum vapor-deposited film and to suppress the deterioration of the oxygen barrier property and the water vapor barrier property even when the cracks occur (). Bending load resistance).

The polyester polyol has two or more hydroxyl groups in one molecule as a functional group. Further, the isocyanate compound has two or more isocyanate groups in one molecule as a functional group. The polyester polyol has, for example, a polyester structure or a polyester polyurethane structure as a main skeleton.

As a specific example of the resin composition (adhesive) containing a polyester polyol, an isocyanate compound, and a phosphoric acid-modified compound, a series of PASLIM sold by DIC Corporation can be used.

The resin composition may further contain a plate-like inorganic compound, a coupling agent, cyclodextrin and / or a derivative thereof and the like.

As the polyester polyol having two or more hydroxyl groups in one molecule as a functional group, for example, the following [1st example] to [3rd example] can be used.
[Example] Polyester polyol obtained by polycondensing an ortho-oriented polyvalent carboxylic acid or its anhydride and a polyhydric alcohol [Example] Polyester polyol having a glycerol skeleton [Example] Having an isocyanul ring Polyester polyols Each polyester polyol will be described below.

The polyester polyol according to the first example is selected from the group consisting of a polyvalent carboxylic acid component containing at least one orthophthalic acid and an anhydride thereof, ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexanedimethanol. It is a polycondensate obtained by polycondensing with a polyhydric alcohol component containing at least one of these.
In particular, a polyester polyol having an orthophthalic acid and its anhydride content of 70 to 100% by mass with respect to all the components of the polyvalent carboxylic acid is preferable.

The polyester polyol according to the first example requires orthophthalic acid and its anhydride as the polyvalent carboxylic acid component, but other polyvalent carboxylic acid components are copolymerized as long as the effects of the present embodiment are not impaired. You may.
Specifically, aliphatic polyvalent carboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid and dodecanediocarboxylic acid, unsaturated bond-containing polyvalent carboxylic acids such as maleic anhydride, maleic acid and fumaric acid, 1, Alicyclic polyvalent carboxylic acids such as 3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, pyromellitic acid, trimellitic acid, 1,4-naphthalenedicarboxylic acid, 2,5- Naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid, 1,2-bis (phenoxy) ethane-p, p'-dicarboxylic acid, anhydrides of these dicarboxylic acids and ester formation of these dicarboxylic acids. Examples thereof include aromatic polyvalent carboxylic acids such as sex derivatives, p-hydroxybenzoic acid, p- (2-hydroxyethoxy) benzoic acid and polybasic acids such as ester-forming derivatives of these dihydroxycarboxylic acids. Among these, succinic acid, 1,3-cyclopentanedicarboxylic acid and isophthalic acid are preferable.
In addition, you may use 2 or more kinds of the above-mentioned other polyvalent carboxylic acids.

As the polyester polyol according to the second example, a polyester polyol having a glycerol skeleton represented by the general formula (1) can be mentioned.
In the general formula (1), R ₁ , R ₂ , and R ₃ are independently H (hydrogen atom) or a group represented by the following general formula (2).

In the formula (2), n represents an integer of 1 to 5, and X is a 1,2-phenylene group, a 1,2-naphthylene group, a 2,3-naphthylene group, 2, which may have a substituent. It represents an arylene group selected from the group consisting of a 3-anthraquinonediyl group and a 2,3-anthracendyl group, and Y represents a group represented by an alkylene group having 2 to 6 carbon atoms).
However, at least one of R ₁ , R ₂ , and R ₃ represents a group represented by the general formula (2).

In the general formula (1), at least one of R ₁ , R ₂ , and R ₃ needs to be a group represented by the general formula (2). Above all, it is preferable that all of R ₁ , R ₂ , and R ₃ are groups represented by the general formula (2).

_Also, tables in the compound R _1, R 2, one of _{R 3} is a group represented by the general formula _(2), R _1, R 2, either _{R 3} 2 two generally formula (2) Any two or more compounds of the compound which is the group to be used and the compound which is the group in which all of R ₁ , R ₂ and R ₃ are represented by the general formula (2) may be a mixture.

X is selected from the group consisting of 1,2-phenylene group, 1,2-naphthylene group, 2,3-naphthylene group, 2,3-anthraquinone diyl group and 2,3-anthracene diyl group, and has a substituent. Represents an allylene group that may be present.
When X is substituted with a substituent, it may be substituted with one or more substituents, the substituent being attached to any carbon atom on X different from the free radical. Examples of the substituent include a chloro group, a bromo group, a methyl group, an ethyl group, an i-propyl group, a hydroxyl group, a methoxy group, an ethoxy group, a phenoxy group, a methylthio group, a phenylthio group, a cyano group, a nitro group and an amino group. Examples thereof include a phthalimide group, a carboxyl group, a carbamoyl group, an N-ethylcarbamoyl group, a phenyl group and a naphthyl group.

In the general formula (2), Y is an ethylene group, a propylene group, a butylene group, a neopentylene group, a 1,5-pentylene group, a 3-methyl-1,5-pentylene group, a 1,6-hexylene group, a methylpentylene group. Represents an alkylene group having 2 to 6 carbon atoms such as a group and a dimethylbutylene group. Among Y, a propylene group and an ethylene group are preferable, and an ethylene group is most preferable.

The polyester resin compound having a glycerol skeleton represented by the general formula (1) contains glycerol, an aromatic polyvalent carboxylic acid in which the carboxylic acid is substituted at the ortho position or an anhydride thereof, and a polyhydric alcohol component as essential components. It can be synthesized by reacting as.

The aromatic polyvalent carboxylic acid in which the carboxylic acid is substituted at the ortho position or its anhydride includes orthophthalic acid or its anhydride, naphthalene 2,3-dicarboxylic acid or its anhydride, naphthalene 1,2-dicarboxylic acid or its anhydride. Anhydrous, anthraquinone 2,3-dicarboxylic acid or an anhydride thereof, 2,3-anthracenecarboxylic acid or an anhydride thereof and the like can be mentioned.
These compounds may have a substituent on any carbon atom of the aromatic ring. Examples of the substituent include a chloro group, a bromo group, a methyl group, an ethyl group, an i-propyl group, a hydroxyl group, a methoxy group, an ethoxy group, a phenoxy group, a methylthio group, a phenylthio group, a cyano group, a nitro group and an amino group. Examples thereof include a phthalimide group, a carboxyl group, a carbamoyl group, an N-ethylcarbamoyl group, a phenyl group and a naphthyl group.

Further, examples of the polyhydric alcohol component include an alkylene diol having 2 to 6 carbon atoms. For example, diols such as ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol and dimethylbutanediol. Can be exemplified.

The polyester polyol according to the third example is a polyester polyol having an isocyanul ring represented by the following general formula (3).
In the general formula (3), R ₁ , R ₂ , and R ₃ are independently "-(CH ₂ ) n1-OH (where n1 represents an integer of 2 to 4)" or the general formula (4). ) Represents the structure.

In the general formula (4), n2 represents an integer of 2 to 4, n3 represents an integer of 1 to 5, X represents a 1,2-phenylene group, a 1,2-naphthylene group, a 2,3-naphthylene group, It represents an arylene group selected from the group consisting of a 2,3-anthraquinonediyl group and a 2,3-anthracendyl group and may have a substituent, and Y represents an alkylene group having 2 to 6 carbon atoms). Represents a group represented by. However, at least one of R ₁ , R ₂ , and R ₃ is a group represented by the general formula (4).

In the general formula (3), the alkylene group represented by − (CH ₂ ) n1- may be linear or branched. Of these, n1 is preferably 2 or 3, and most preferably 2.

In the general formula (4), n2 represents an integer of 2 to 4, and n3 represents an integer of 1 to 5.
X is selected from the group consisting of 1,2-phenylene group, 1,2-naphthylene group, 2,3-naphthylene group, 2,3-anthraquinonediyl group, and 2,3-anthracenediyl group and has a substituent. Represents an allylene group that may be present.

When X is substituted with a substituent, it may be substituted with one or more substituents, the substituent being attached to any carbon atom on X different from the free radical. Examples of the substituent include a chloro group, a bromo group, a methyl group, an ethyl group, an i-propyl group, a hydroxyl group, a methoxy group, an ethoxy group, a phenoxy group, a methylthio group, a phenylthio group, a cyano group, a nitro group and an amino group. Examples thereof include a phthalimide group, a carboxyl group, a carbamoyl group, an N-ethylcarbamoyl group, a phenyl group and a naphthyl group.
The substituent of X is preferably a hydroxyl group, a cyano group, a nitro group, an amino group, a phthalimide group, a carbamoyl group, an N-ethylcarbamoyl group and a phenyl group, preferably a hydroxyl group, a phenoxy group, a cyano group, a nitro group, a phthalimide group and The phenyl group is most preferred.

In the general formula (4), Y is an ethylene group, a propylene group, a butylene group, a neopentylene group, a 1,5-pentylene group, a 3-methyl-1,5-pentylene group, a 1,6-hexylene group, a methylpentylene group. Represents an alkylene group having 2 to 6 carbon atoms such as a group and a dimethylbutylene group. Among Y, a propylene group and an ethylene group are preferable, and an ethylene group is most preferable.

In the general formula (3), at least one of R ₁ , R ₂ , and R ₃ is a group represented by the general formula (4). Above all, it is preferable that all of R ₁ , R ₂ , and R ₃ are groups represented by the general formula (4).

_Also, tables in the compound R _1, R 2, one of _{R 3} is a group represented by the general formula _(4), R _1, R 2, either _{R 3} 2 two generally formula (4) Any two or more compounds of the compound which is the group to be used and the compound which is the group in which all of R ₁ , R ₂ and R ₃ are represented by the general formula (4) may be a mixture.

The polyester polyol having an isocyanul ring represented by the general formula (3) includes a triol having an isocyanul ring, an aromatic polyvalent carboxylic acid in which the carboxylic acid is substituted at the ortho position or an anhydride thereof, and a polyhydric alcohol component. Can be synthesized by reacting with

Triols having an isocyanuric ring include, for example, alkylene oxide adducts of isocyanuric acid such as 1,3,5-tris (2-hydroxyethyl) isocyanuric acid and 1,3,5-tris (2-hydroxypropyl) isocyanuric acid. And so on.

Examples of the aromatic polyvalent carboxylic acid in which the carboxylic acid is substituted at the ortho position or its anhydride include orthophthalic acid or its anhydride, naphthalene 2,3-dicarboxylic acid or its anhydride, and naphthalene 1,2-dicarboxylic acid. Or an anhydride thereof, anthraquinone 2,3-dicarboxylic acid or an anhydride thereof, and 2,3-anthracenecarboxylic acid or an anhydride thereof. These compounds may have a substituent on any carbon atom of the aromatic ring.

Examples of the substituent include a chloro group, a bromo group, a methyl group, an ethyl group, an i-propyl group, a hydroxyl group, a methoxy group, an ethoxy group, a phenoxy group, a methylthio group, a phenylthio group, a cyano group, a nitro group and an amino group. Examples thereof include a phthalimide group, a carboxyl group, a carbamoyl group, an N-ethylcarbamoyl group, a phenyl group and a naphthyl group.

Further, examples of the polyhydric alcohol component include an alkylene diol having 2 to 6 carbon atoms. For example, diols such as ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol and dimethylbutanediol. Can be mentioned.
Among them, 1,3,5-tris (2-hydroxyethyl) isocyanuric acid or 1,3,5-tris (2-hydroxypropyl) isocyanuric acid is used as the triol compound having an isocyanul ring, and the carboxylic acid is in the ortho position. A polyester polyol compound having an isocyanul ring using an aromatic polyvalent carboxylic acid substituted with or using orthophthalic anhydride as its anhydride and ethylene glycol as the polyhydric alcohol is particularly excellent in oxygen barrier property and adhesiveness. preferable.

The isocyanul ring is highly polar and trifunctional, and can increase the polarity of the entire system and increase the crosslink density. From this point of view, it is preferable to contain isocyanul ring in an amount of 5% by mass or more based on the total solid content of the adhesive resin.

The isocyanate compound has two or more isocyanate groups in the molecule.
Further, the isocyanate compound may be aromatic, aliphatic, low molecular weight compound, or high molecular weight compound.
Further, the isocyanate compound may be a blocked isocyanate compound obtained by an addition reaction using a known isocyanate blocking agent by a known and commonly used appropriate method.
Among them, a polyisocyanate compound having three or more isocyanate groups is preferable from the viewpoint of adhesiveness and retort resistance, and an aromatic compound is preferable from the viewpoint of oxygen barrier property and water vapor barrier property.

Specific examples of the isocyanate compound include tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydride diphenylmethane diisocyanate, metaxylylene diisocyanate, hydride hydride diisocyanate, isophorone diisocyanate, and these isocyanate compounds. Examples thereof include an adduct, a burette, and an allophanate obtained by reacting these isocyanate compounds with a low molecular weight active hydrogen compound or an alkylene oxide adduct thereof, or a high molecular weight active hydrogen compound.
Examples of the low molecular weight active hydrogen compound include ethylene glycol, propylene glycol, metaxylylene alcohol, 1,3-bishydroxyethylbenzene, 1,4-bishydroxyethylbenzene, trimethylolpropane, glycerol, pentaerythritol, erythritol, and sorbitol. Examples thereof include ethylenediamine, monoethanolamine, diethanolamine, triethanolamine and metaxylylene diamine, and examples of the molecularly active hydrogen compound include various polyester resins, polyether polyols and high molecular weight active hydrogen compounds of polyamide.

The phosphoric acid-modified compound is, for example, a compound represented by the following general formula (5) or (6).
In the general formula (5), R ₁ , R ₂ , and R ₃ are hydrogen atoms, alkyl groups having 1 to 30 carbon atoms, (meth) acryloyl groups, phenyl groups which may have substituents, and (meth) acryloyl. It is a group selected from alkyl groups having 1 to 4 carbon atoms having an oxy group, but at least one is a hydrogen atom, and n represents an integer of 1 to 4.
In the formula, R ₄ and R ₅ have a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, a (meth) acryloyl group, a phenyl group which may have a substituent, and a (meth) acryloyloxy group. It is a group selected from alkyl groups of ~ 4, n represents an integer of 1 to 4, x represents an integer of 0 to 30, y represents an integer of 0 to 30, except when x and y are both 0. ..

More specifically, phosphoric acid, pyrophosphate, triphosphate, methyl acid phosphate, ethyl acid phosphate, butyl acid phosphate, dibutyl phosphate, 2-ethylhexyl acid phosphate, bis (2-ethylhexyl) phosphate, isododecyl acid phosphate, butoxy. Ethyl acid phosphate, oleyl acid phosphate, tetracosyl acid phosphate, 2-hydroxyethyl methacrylate acid phosphate, polyoxyethylene alkyl ether phosphoric acid and the like can be mentioned, and one or more of these can be used.

The content of the phosphoric acid-modified compound in the resin composition is preferably 0.005% by mass or more and 10% by mass or less, and more preferably 0.01% by mass or more and 1% by mass or less.
By setting the content of the phosphoric acid-modified compound to 0.005% by mass or more, the oxygen barrier property and the water vapor barrier property of the laminate of the present invention can be improved. Further, by setting the content of the phosphoric acid-modified compound to 10% by mass or less, the adhesiveness of the adhesive layer can be improved.

The resin composition containing the polyester polyol, the isocyanate compound, and the phosphoric acid-modified compound may contain a plate-like inorganic compound, whereby the adhesiveness of the adhesive layer can be improved. In addition, the bending load resistance of the laminated body of the present invention can be improved.
Plate-like inorganic compounds include, for example, kaolinite-serpentinite clay minerals (haloisite, kaolinite, enderite, dicite, nacrite, antigolite, chrysotile, etc.) and pyrophyllite-talc (pyrophilite, talc, etc.). Kerorai, etc.).

Examples of the coupling agent include a silane-based coupling agent represented by the following general formula (7), a titanium-based coupling agent, an aluminum-based coupling agent, and the like. In addition, these coupling agents may be used alone or in combination of two or more types.

Examples of the silane coupling agent include vinyl trichlorosilane, vinyl trimethoxysilane, vinyl triethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ. -Glysidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxytrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxy Propylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (amino) Ethyl) γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyl Examples thereof include trimethoxysilane, 3-isocyanuspropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane and 3-triethoxysilyl-N- (1,3-dimethyl-butylidene).

Examples of titanium-based coupling agents include isopropyltriisostearoyl titanate, isopropyltri (N-aminoethyl-aminoethyl) titanate, isopropyltridodecylbenzenesulfonyl titanate, isopropyltris (dioctylpyrophosphate) titanate, and tetraoctylbis. (Didodecylphosphite) titanate, tetraoctylbis (ditridecylphosphite) titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltrioctainoltitanate, isopropyldimethacrylisostearoyl titanate , Isostatearoyl diacrylic titanate, diisostearoyl ethylene titanate, isopropyltri (dioctyl phosphate) titanate, isopropyltricylphenyl titanate and dicumylphenyloxyacetate titanate and the like.

Specific examples of the aluminum-based coupling agent include acetalkoxyaluminum diisopropyrate, diisopropoxyaluminum ethylacetate, diisopropoxyaluminum monomethacrylate, isopropoxyaluminum alkylacetate monomethacrylate, and aluminum. Examples thereof include -2-ethylhexanoate oxide trimmer, aluminum stearate oxide trimmer and alkylacetate aluminum oxide trimmer.

The resin composition can contain cyclodextrin and / or its derivatives, which can improve the adhesiveness of the adhesive layer. In addition, the bending load resistance of the laminated body of the present invention can be further improved.
Specifically, for example, a cyclodextrin such as cyclodextrin, alkylated cyclodextrin, acetylated cyclodextrin, and hydroxyalkylated cyclodextrin in which the hydrogen atom of the hydroxyl group of the glucose unit is replaced with another functional group is used. Can be done. A branched cyclic dextrin can also be used.
The cyclodextrin skeleton of cyclodextrin and cyclodextrin derivatives is α-cyclodextrin consisting of 6 glucose units, β-cyclodextrin consisting of 7 glucose units, and γ-cyclodextrin consisting of 8 glucose units. It may be either.
These compounds may be used alone or in combination of two or more. In addition, these cyclodextrins and / or derivatives thereof may be collectively referred to as dextrin compounds hereafter.

From the viewpoint of compatibility and dispersibility in the resin composition, it is preferable to use a cyclodextrin derivative as the cyclodextrin compound.

Examples of the alkylated cyclodextrin include methyl-α-cyclodextrin, methyl-β-cyclodextrin and methyl-γ-cyclodextrin. These compounds may be used alone or in combination of two or more.

Examples of the acetylated cyclodextrin include monoacetyl-α-cyclodextrin, monoacetyl-β-cyclodextrin and monoacetyl-γ-cyclodextrin. These compounds may be used alone or in combination of two or more.

Examples of the hydroxyalkylated cyclodextrin include hydroxypropyl-α-cyclodextrin, hydroxypropyl-β-cyclodextrin and hydroxypropyl-γ-cyclodextrin. These compounds may be used alone or in combination of two or more.

To the extent that the properties of the present invention are not impaired, the adhesive layer comprises pigments such as titanium oxide, zinc oxide and carbon black, dyes such as disperse dyes, acidic dyes and cationic dyes, antioxidants, lubricants, colorants and stabilizers. Additives such as agents, wetting agents, thickeners, coagulants, gelling agents, antisettling agents, softening agents, hardening agents, plasticizing agents, leveling agents, UV absorbers and flame retardants can be included.

The thickness of the adhesive layer is not particularly limited, and can be, for example, 1 μm or more and 10 μm or less.

(Mesosphere)
In one embodiment, the laminate of the present invention comprises a polyethylene layer or a polypropylene layer as an intermediate layer.

The polyethylene layer or polypropylene layer may be composed of a stretched film, may be a uniaxially stretched film, or may be a biaxially stretched film, and the preferable stretch ratio is as described above.
Further, the polyethylene layer or polypropylene layer may be an extruded resin layer formed by melt-extruding polyethylene or polypropylene.

The thickness of the polyethylene layer or polypropylene layer is preferably 10 μm or more and 70 μm or less, and more preferably 15 μm or more and 50 μm or less.

In one embodiment, the laminate of the present invention includes a gas barrier layer made of a gas barrier resin as an intermediate layer.
By providing such an intermediate layer in the laminate of the present invention, the oxygen barrier property and the water vapor barrier property can be improved.
Examples of the gas barrier resin include polyamides such as ethylene-vinyl alcohol copolymer (EVOH), polyvinyl alcohol, polyacrylonitrile, nylon 6, nylon 6,6 and polymethaxylylene adipamide (MXD6), polyesters and polyurethanes. In addition, (meth) acrylic resin and the like can be mentioned.

The thickness of the gas barrier layer is preferably 0.01 μm or more and 10 μm or less, and more preferably 0.1 μm or more and 5 μm or less.
By setting the thickness of the gas barrier layer to 0.01 μm or more, the oxygen barrier property and the water vapor barrier property of the laminate of the present invention can be further improved. By setting the thickness of the gas barrier layer to 10 μm or less, the recyclability of the laminate of the present invention can be maintained.

In one embodiment, the intermediate layer comprises a thin film. The mode, preferable thickness, forming method and the like of the vapor-deposited film that can be used are as described above.

In one embodiment, the intermediate layer comprises a barrier coat layer. The structure, preferable thickness, forming method and the like of the barrier coat layer are as described above.

(Packaging bag)
The packaging bag of the present invention is characterized by being composed of the above-mentioned laminate.
The shape of the packaging bag is not particularly limited, and as shown in FIG. 4, a stand pouch having a bag-like shape may be used.

In one embodiment, the packaging bag 20 of the present invention may be a stand pouch including a nozzle portion 21 for pouring as shown in FIG. 5 when the content is a liquid, a viscous body, or a powder. ..
Further, from the viewpoint of ease of opening, the packaging bag 20 may be provided with a curved portion 22 that is curved inward, as shown in FIG.
Further, the cutting portion 23 formed by a laser beam or the like may be provided.

In one embodiment, the packaging bag 30 of the present invention may be a stand pouch including a spout 32 interposed by an upper edge seal portion 31, as shown in FIG. A lid plug 33 is screwed to the upper end of the spout 32. The material of this spout is not particularly limited, but is made of polyethylene when the base material and the sealant layer are made of polyethylene, and polypropylene when the base material and the sealant layer are made of polypropylene. It is preferably configured.

In FIGS. 4 to 6, the shaded portion represents the heat-sealed portion. Further, in FIGS. 3 to 5, a stand pouch is illustrated as a packaging bag, but the present invention is not limited to this.

In one embodiment, the packaging bag can be manufactured by folding and stacking the laminates of the present invention in half so that the sealant layer is on the inside, and heat-sealing the ends thereof.
In another embodiment, the packaging bag can also be manufactured by stacking two laminates so that the sealant layers face each other and heat-sealing the ends thereof.

Further, in one embodiment, the packaging bag is formed by stacking two of the above laminated bodies so that the sealant layers face each other and heat-sealing the two sides to form a body portion, and then another one. The laminate can be manufactured by folding it in a V shape so that the sealant layer is on the outside, sandwiching it from one end of the body portion, and heat-sealing it to form a bottom portion.

Further, in one embodiment, the packaging bag is formed by stacking two of the above laminated bodies so that the sealant layers face each other and heat-sealing one side to form a bottom, and then another two laminated bodies. The body can be manufactured by folding it in a V shape so that the sealant layer is on the outside, sandwiching it from both ends of the laminated bodies facing each other, and heat-sealing it to form a body portion.

The heat sealing method is not particularly limited, and for example, a known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, and an ultrasonic seal can be used.

The contents to be filled in the packaging bag are not particularly limited, and the contents may be liquid, powder or gel. Moreover, it may be food or non-food.
According to the packaging bag according to the present invention, even if the content is colored such as detergent, it does not affect the image formed on the base material, and therefore can be suitably filled.

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

Example 1
As a base film, a vertically uniaxially stretched polyethylene film having a thickness of 25 μm (stretching ratio: about 5 times) was prepared.

A silica-deposited film having a thickness of 0.03 μm was formed on one surface of the base film by the CVD method.

Mixing 385 g of water, 67 g of isopropyl alcohol and 9.1 g of 0.5N hydrochloric acid,
Solution A was prepared by mixing 175 g of tetraethoxysilane as a metal alkoxide and 9.2 g of glycidoxypropyltrimethoxysilane as a silane coupling agent with a solution adjusted to pH 2.2 while cooling to 10 ° C. ..
Further, as a water-soluble polymer, a solution B was prepared by mixing 14.7 g of polyvinyl alcohol having a degree of polymerization of 99% or more, 324 g of water, and 17 g of isopropyl alcohol.
Next, solution A and solution B are mixed so as to have a weight ratio of 6.5: 3.5 to prepare a barrier coating agent, which is applied onto a vapor-deposited film by a spin coating method, and heat-treated. A barrier coat layer was formed.
An image was formed on this barrier coat layer by a gravure printing machine.

A two-component curable polyester adhesive of 3.0 g / m ^{2 is} applied onto the barrier coat layer formed as described above, and an unstretched polyethylene film having a thickness of 80 μm is dry-laminated to obtain the laminate of the present invention. Obtained.
The oxygen permeability of this laminate was measured in an environment of 23 ° C. and 50% relative humidity using OXTRAN2 / 20 manufactured by MOCON in the United States in accordance with JIS K 7126 (isopressure method), and it was 1.42 cc. It was / m ² · d · atm.
Further, the water vapor permeability of the laminate was measured in an environment of 40 ° C. and 90% relative humidity using PERMATRAN 3/31 manufactured by MOCON in the United States in accordance with the JIS K 7129B method. As a result, 1.55 g / It was m ² · d.

The laminate was cut into a size of 100 mm in width × 150 mm in length.
The two laminates cut as described above are laminated so that the two sealant layers face each other, and cut into a size of 100 mm in width × 50 mm in length from both ends so that the sealant is on the outside. The laminated body folded in a shape was sandwiched.
Next, one vertical side and the side sandwiching the V-shaped laminate were heat-sealed to obtain a packaging bag.

A polyethylene spout made by injection molding by filling a jelly beverage from the opening of the packaging bag is tightly adhered by heat-sealing the opening, and the lid stopper made by injection molding is used as a spout. It was screwed into a stand pouch-shaped packaging bag. No leaks, falls, bucklings, etc. were observed in the packaging bag, and no bag breakage, leaks, etc. were observed when the drop test from 1.2 m was performed 5 times.

Example 2
Example 1 except that the base film was changed to a biaxially stretched polypropylene film having a thickness of 25 μm (stretching ratio: 3 to 6 times) and the sealant layer was changed to an unstretched polypropylene film having a thickness of 60 μm. In the same manner as above, the laminate of the present invention was produced.
When the oxygen permeability and the water vapor permeability of the laminate were measured in the same manner as in Example 1, they were 1.27 cc / m ² · d · atm and 0.75 g / m ² · d, respectively.
Further, as in Example 1, a packaging bag was produced. No leaks, falls, bucklings, etc. were observed in the packaging bag, and no bag breakage, leaks, etc. were observed when the drop test from 1.2 m was performed 5 times.
The spout used was made of polypropylene.

Example 3
As a base film, a biaxially stretched polypropylene film having a thickness of 25 μm (stretching ratio: 3 to 6 times) was prepared. An image was formed on one of the surfaces by a gravure printing machine.

The barrier coating agent was applied to the image-forming surface of the base film by a spin coating method and heat-treated to form a barrier coating layer.

A silica vapor deposition film having a thickness of 0.03 μm was formed on the barrier coat layer by a CVD method.

A two-component curable polyester adhesive of 3.0 g / m2 is applied onto the silica-deposited film layer formed as described above, and an unstretched polypropylene film having a thickness of 60 μm is dry-laminated to obtain the laminate of the present invention. Obtained.

Further, as in Example 1, a packaging bag was produced. No leaks, falls, bucklings, etc. were observed in the packaging bag, and no bag breakage, leaks, etc. were observed when the drop test from 1.2 m was performed 5 times.
The spout used was made of polypropylene.

Comparative Example 1
A laminate was produced in the same manner as in Example 1 except that the barrier coat layer was not provided.
When the oxygen permeability of the laminated body was measured in the same manner as in Example 1, the numerical value could not be measured large. Moreover, when the water vapor permeability was measured, it was 7.92 g / m ² · d.
Further, as in Example 1, a packaging bag was produced. No leaks, falls, bucklings, etc. were observed in the packaging bag, and no bag breakage, leaks, etc. were observed when the drop test from 1.2 m was performed 5 times.

Comparative Example 2
A laminate was produced in the same manner as in Example 1 except that the base film was changed to an unstretched polyethylene film having a thickness of 25 μm.
When the oxygen permeability of the laminated body was measured in the same manner as in Example 1, the numerical value could not be measured large. Moreover, when the water vapor permeability was measured, it was 4.13 g / m ² · d.
Further, as in Example 1, an attempt was made to produce a packaging bag, but the heat resistance of the base film was not sufficient and heat sealing could not be performed.

10: Laminate, 11: Base material, 12: Sealant layer, 13: Barrier coat layer, 14: Light-shielding printing layer, 15: Light-shielding layer, 16: Laminate layer, 17; Heat seal layer, 20: Packaging bag, 21 : Dispensing nozzle part, 22: Curved part, 23: Cutting part, 30: Packaging bag, 31: Upper edge seal part, 32: Spout, 33: Lid plug

Claims (8)

A laminated body including a base material and a sealant layer.
The base material and the sealant layer are made of the same material.
The base material is subjected to at least one of stretching treatment and electron beam irradiation treatment.
The same material is polyethylene or polypropylene.
A laminate, characterized in that a barrier coat is provided between the base material and the sealant layer. The barrier coat layer is a gas barrier coating film containing at least one metal alkoxide hydrolyzate or a metal alkoxide hydrolyzate obtained by polycondensing a mixture of a metal alkoxide and a water-soluble polymer by a sol-gel method. The laminate according to claim 1. The laminate according to claim 1 or 2, wherein the barrier coat layer has a thickness of 0.01 μm or more and 100 μm or less. The laminate according to any one of claims 1 to 3, further comprising a thin-film film between the base material and the barrier coat layer, or between the barrier coat layer and the sealant layer. The laminate according to claim 4, wherein the vapor-deposited film is composed of an inorganic oxide. The laminate according to any one of claims 1 to 5, which is used for packaging bags. A packaging bag comprising the laminate according to any one of claims 1 to 6. The packaging bag of claim 7, comprising a spout.