JP6706428B2 - Laminate - Google Patents

Description

The present invention relates to a laminate, and more particularly to a laminate using a biomass polyester resin.

Plastics, which are materials derived from fossil fuels, are mainly used in the production of packaging materials for filling merchandise such as pharmaceuticals, cosmetics, and foods, from the viewpoint of ease of molding and cost, and these plastic materials are It is produced from petroleum, which is a fossil resource. Polyester resins, polyolefin resins, polyamide resins, and the like are used as plastic materials that are widely used as materials for packaging containers. Among them, polyester resins are widely used in various industrial applications such as films, sheets and packaging containers because they are excellent in mechanical properties, chemical stability, heat resistance, transparency and the like and are inexpensive.

Polyester is obtained by polycondensing a diol unit and a dicarboxylic acid unit. For example, polyethylene terephthalate (hereinafter sometimes abbreviated as PET) is obtained by subjecting ethylene glycol and terephthalic acid as raw materials to an esterification reaction of both. It is manufactured by subjecting it to polycondensation reaction. These raw materials are produced from petroleum which is a fossil resource, for example, ethylene glycol is industrially produced from ethylene and terephthalic acid is produced from xylene.

In recent years, with respect to materials derived from such fossil fuels, there is an increasing tendency to use petroleum alternative raw materials for various purposes in consideration of the environment. In order to reduce CO ₂ emission, it is necessary to escape from fossil fuels. Is desired. As an attempt to reduce the use of fossil fuels, biomass plastics using biomass raw materials as a part of raw materials for various resins have been put into practical use as packaging materials. As an example, a polyester resin that uses biomass-derived ones as ethylene glycol, which is a monomer component, has been put into practical use, and it is also proposed to apply a polyester resin containing such a biomass-derived raw material to a packaging material. ing. For example, in Patent Document 1, a packaging film using a resin film containing a polyester (hereinafter, also referred to as a biomass polyester) obtained by using a biomass-derived ethylene glycol and a fossil fuel-derived dicarboxylic acid as a base layer. Etc. have been proposed. Further, in Patent Document 2, even when a film is made of a resin containing biomass polyester in a proportion of 50 to 95% by mass, physical properties comparable to those of a film using a conventional fossil fuel-derived polyester resin are obtained. It is also proposed to be obtained.

JP2012-96469A JP2012-97163A

By the way, in a packaging film having a polyester resin or the like as a base material layer, a sealant layer is provided on the inner layer side, and a packaging body is formed by heat sealing from the outer layer side (base material layer side). When sealing, the film may be pressed by the male mold and the female mold. The present inventors have noticed that when such a seal is applied or when the film is bent, the film is cracked when the biomass polyester resin is used as the base material layer. Then, as a result of earnest study, it was found that the occurrence of cracks as described above can be suppressed by containing isophthalic acid in addition to terephthalic acid as a dicarboxylic acid component constituting the biomass polyester. The present invention is based on such findings.

Therefore, an object of the present invention is to provide a laminate in which the flexibility is improved in a laminate in which a polyester resin layer containing biomass polyester and a thin film layer are laminated.

A paper container according to the present invention includes at least a second sealant layer, a paper layer, a polyester resin layer having a thin film layer containing at least one of an inorganic substance and an inorganic oxide on one surface, and a first resin layer . and the sealant layer of, but in turn comprises a stacked laminate a paper container which borders the processing has been performed,
The polyester resin layer is a biaxially stretched film containing a biomass polyester resin containing ethylene glycol derived from biomass as a diol unit and dicarboxylic acid derived from fossil fuel as a dicarboxylic acid unit,
The dicarboxylic acid contains terephthalic acid and isophthalic acid,
The content of the isophthalic acid is 2.5 mol% or less based on all dicarboxylic acid units constituting the biomass polyester resin.

Further, in the present invention, the first and/or second sealant layer contains a resin material derived from fossil fuel or biomass, and the resin material is selected from the group consisting of polyethylene, polypropylene, and polylactic acid. It may contain a resin.

According to the present invention, in a laminate having a polyester resin layer containing a biomass polyester resin having a biomass-derived ethylene glycol as a diol unit and a fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit, isophthalic acid is used as a dicarboxylic acid component. By including it, it is possible to realize a laminate that can improve flexibility.

Sectional drawing which shows simply the embodiment of the laminated constitution of the laminated body by this invention. Sectional drawing which shows simply the other embodiment of the laminated constitution of the laminated body by this invention. The figure which shows simply an example of a structure of a standing pouch. Sectional drawing which shows briefly embodiment of the laminated constitution of the laminated body which forms the side sheet of a standing pouch. The partial cross section figure which shows an example of a tube container simply. Sectional drawing which shows briefly embodiment of the laminated constitution of the laminated body which forms the cylindrical trunk|drum of a tube container. Sectional drawing which shows simply the embodiment of the laminated constitution of the laminated body which forms a liquid paper container. The perspective view which shows an example of a liquid paper container. Sectional drawing which shows briefly embodiment of the laminated constitution of the laminated body which forms a paper cup. The perspective view which cut off a part of paper cup. The front view which fractured|ruptured a part which shows another embodiment of a paper cup.

[Definition]
In this specification,
"Polyester" means a polymer obtained by a polycondensation reaction of a diol unit and a dicarboxylic acid unit.
Further, the “fossil fuel polyester” means a polymer having a diol derived from fossil fuel as a diol unit and a dicarboxylic acid derived from fossil fuel as a dicarboxylic acid unit.
Further, the “biomass polyester” means a polymer having ethylene glycol derived from biomass as a diol unit and dicarboxylic acid derived from fossil fuel as a dicarboxylic acid unit.

Hereinafter, modes for carrying out the present invention (hereinafter referred to as embodiments) will be described in detail with reference to the drawings. The present invention is not limited to the embodiments described below. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the constituent elements disclosed in the following embodiments can be combined appropriately.

The laminate according to the present invention will be described with reference to the drawings. As shown in FIG. 1, a laminate 10 according to the present invention is a laminate in which at least a polyester resin layer 1 and a thin film layer 2 are laminated. In the present invention, as shown in FIG. 2, the laminate 10 according to the present invention may be a laminate in which a polyester resin layer 1, a thin film layer 2 and a barrier coat film 3 are sequentially provided. Hereinafter, each layer constituting the laminate according to the present invention will be described.

[Polyester resin layer]
The polyester resin layer 1 constituting the laminate according to the present invention contains a biomass polyester resin. As described above, the biomass polyester contains biomass-derived ethylene glycol as a diol unit and fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit. The present invention is characterized in that it contains terephthalic acid and isophthalic acid as a dicarboxylic acid unit which is a copolymerization component of biomass polyester. Conventional biomass polyesters were obtained by polycondensing biomass-derived ethylene glycol and terephthalic acid. Therefore, in a laminate using a biomass polyester resin as a base material layer, a package using the laminate is used. When it was manufactured, cracks were sometimes generated. Focusing on this problem, the present invention has found that the flexibility of the laminate can be improved by adding isophthalic acid in addition to terephthalic acid as the dicarboxylic acid unit which is the acid component of the biomass polyester. Hereinafter, the biomass polyester used in the present invention will be described.

The biomass-derived ethylene glycol uses ethanol produced from biomass as a raw material (biomass ethanol). The biomass-derived ethylene glycol can be obtained from biomass ethanol by a conventionally known method such as a method of producing ethylene glycol via ethylene oxide. Moreover, the commercially available biomass ethylene glycol may be used, and for example, the biomass ethylene glycol sold by India Glycol can be preferably used.

As the dicarboxylic acid unit, a dicarboxylic acid derived from fossil fuel is used, and as the dicarboxylic acid derived from fossil fuel, terephthalic acid and isophthalic acid are contained as essential components. In the present invention, by containing isophthalic acid in addition to terephthalic acid as a dicarboxylic acid unit, the flexibility of the resulting biomass polyester is improved, and as a result, the crack resistance when formed into a laminate is improved. Conceivable. The content of isophthalic acid is preferably 0.5 to 2.5 mol%, and more preferably 1.0 to 2.5 mol%, based on all dicarboxylic acid units constituting the biomass polyester. If it is less than 0.5 mol %, the flexibility may not be improved, while if it exceeds 2.5 mol %, the melting point of the biomass polyester may be lowered and the heat resistance may be insufficient.

The biomass polyester can be obtained by a conventionally known method of polycondensing the above-mentioned diol unit and dicarboxylic acid unit. Specifically, a general method for melt polymerization, such as an esterification reaction and/or a transesterification reaction of the above diol unit and a dicarboxylic acid unit, and then a polycondensation reaction under reduced pressure, or an organic solvent Can be produced by a known solution heating dehydration condensation method using

The amount of the diol unit used in producing the biomass polyester is substantially equimolar with respect to 100 mol of the dicarboxylic acid or its derivative, but in general, esterification and/or transesterification reaction and/or polycondensation are conducted. Since there is distillation during the reaction, it is used in an excess of 0.1 to 20 mol %.

The polycondensation reaction is preferably performed in the presence of a polymerization catalyst. The timing of adding the polymerization catalyst is not particularly limited as long as it is before the polycondensation reaction, and may be added at the time of charging the raw materials or at the start of depressurization.

The obtained biomass polyester may be solid-phase polymerized, if necessary, in order to further increase the degree of polymerization and to remove oligomers such as cyclic trimers after solidification. Specifically, after the biomass polyester is made into chips and dried, the biomass polyester is pre-crystallized by heating at a temperature of 100 to 180° C. for 1 to 8 hours, and subsequently, at a temperature of 190 to 230° C. It is carried out by heating in an inert gas atmosphere or under reduced pressure for 1 hour to several tens of hours.

The intrinsic viscosity of the obtained biomass polyester is preferably 0.5 dl/g to 1.5 dl/g, and more preferably 0.6 dl/g to 1.2 dl/g. When the intrinsic viscosity is less than 0.5 dl/g, the mechanical properties required for the biomass polyester film as a semi-transmissive reflective film substrate, such as tear strength, may be insufficient. On the other hand, if the intrinsic viscosity exceeds 1.5 dl/g, the productivity in the raw material manufacturing process and the film forming process will be impaired. The intrinsic viscosity is measured with an orthochlorophenol solution at 35°C.

In the biomass polyester, the content of carbon derived from the biomass measured by radioactive carbon (C14) is preferably 10 to 30% of the total carbon in the biomass polyester. Since carbon dioxide in the atmosphere contains C14 at a constant rate (105.5 pMC), the content of C14 in plants that grow by taking in carbon dioxide in the atmosphere, for example, corn, is also about 105.5 pMC. It is known. It is also known that fossil fuel contains almost no C14. Therefore, the proportion of carbon derived from biomass can be calculated by measuring the proportion of C14 contained in all carbon atoms in the biomass polyester. In the present invention, when the content of C14 in the biomass polyester is P _C14 , the content P _bio of carbon derived from biomass is defined as in the following formula (1).
P _bio (%)=P _C14 /105.5×100 (1)

The polyester resin layer 1 that constitutes the laminate of the present invention may contain other components. In the polyester resin layer 1, the content of biomass-derived carbon measured by radioactive carbon (C14) is preferably 10 to 30% of the total carbon in the polyester resin layer 1, and is preferably 15 to 25%. Is more preferable. Other components contained in the polyester resin layer 1 may be polyesters such as polyester derived from fossil fuel and recycled polyester, and polyethylene such as polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate and polypropylene terephthalate. A polyester resin other than terephthalate may be contained.

The polyester resin layer 1 can be formed, for example, by forming a film from the resin described above by a T-die method. Specifically, after drying the resin composition described above, the resin composition is melted by supplying the resin composition to a melt extruder heated to a temperature (Tm) to Tm+70° C. higher than the melting point of polyester to melt the resin composition. A film can be formed by extruding into a sheet form from a die such as a T die and rapidly quenching and solidifying the extruded sheet form with a rotating cooling drum or the like. As the melt extruder, a single-screw extruder, a twin-screw extruder, a vent extruder, a tandem extruder or the like can be used according to the purpose.

The film obtained as described above is preferably biaxially stretched. Biaxial stretching can be performed by a conventionally known method. For example, the film extruded onto the cooling drum as described above is subsequently heated by roll heating, infrared heating or the like, and stretched in the longitudinal direction to obtain a longitudinally stretched film. This stretching is preferably performed by utilizing the peripheral speed difference between two or more rolls. The longitudinal stretching is usually performed in the temperature range of 50 to 100°C. The longitudinal stretching ratio is preferably 2.5 times or more and 4.2 times or less, though it depends on the required characteristics of the film application. When the draw ratio is less than 2.5 times, it is difficult to obtain a good film because the polyester film has large unevenness in thickness.

The longitudinally stretched film is sequentially subjected to the treatment steps of transverse stretching, heat setting and heat relaxation to obtain a biaxially stretched film. The transverse stretching is usually performed in the temperature range of 50 to 100°C. The transverse stretching ratio is preferably 2.5 times or more and 5.0 times or less, though it depends on the properties required for this application. When it is less than 2.5 times, it is difficult to obtain a good film because the thickness unevenness of the film becomes large, and when it exceeds 5.0 times, breakage easily occurs during film formation.

After the transverse stretching, a heat setting treatment is subsequently carried out, but a preferable heat setting temperature range is Tg+70 to Tm-10° C. of polyester. The heat setting time is preferably 1 to 60 seconds. Further, for applications requiring a low heat shrinkage, heat relaxation treatment may be carried out as necessary.

The thickness of the stretched film of the resin film obtained as described above is arbitrary depending on the application, but is usually 5 to 100 μm, preferably 5 to 25 μm. Breaking strength of such a resin film is 5 to 35 kg / mm ² at 5~40kg / ^mm 2, TD direction MD direction, elongation at break, 50 to 350% in MD direction, the TD direction It is 50 to 300%. Further, the shrinkage rate when left for 30 minutes in a temperature environment of 150° C. is 0.1 to 5%.

[Thin film layer]
The thin film layer 2 is a thin film layer containing at least one of an inorganic substance and an inorganic oxide. By providing the laminated body with the thin film layer on at least one surface of the polyester resin layer 1, it is possible to improve the gas barrier property for preventing permeation of oxygen gas, water vapor and the like. The laminated body may include two or more thin film layers. When two or more thin film layers are provided, they may have the same composition or different compositions.

Examples of the thin film layer include silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B), titanium (Ti). ), lead (Pb), zirconium (Zr), yttrium (Y) and the like, or inorganic oxides can be used. In particular, as a material suitable for a package or the like, a vapor deposition film of silicon oxide or aluminum metal or aluminum oxide is preferably used.

In the present invention, the film thickness of the thin film layer of the inorganic material or the inorganic oxide as described above varies depending on the type of the inorganic material or the inorganic oxide used, but is, for example, 50 to 2000 Å position, preferably 100 to 1000 Å position. It is desirable to form it by arbitrarily selecting within the range. More specifically, in the case of a vapor deposited film of aluminum, a film thickness of 50 to 600 Å, more preferably 100 to 450 Å is desirable, and in the case of a vapor deposited film of aluminum oxide or silicon oxide, The film thickness is preferably 50 to 500Å, more preferably 100 to 300Å.

Examples of the method for forming the thin film layer 2 include a physical vapor deposition method (Physical Vapor Deposition method, PVD method) such as a vacuum vapor deposition method, a sputtering method, and an ion plating method, or a plasma chemical vapor deposition method, a thermal method. Examples thereof include chemical vapor deposition methods and chemical vapor deposition methods such as photochemical vapor deposition methods (Chemical Vapor Deposition method, CVD method) and the like.

The laminate according to the present invention, in addition to the polyester resin layer 1 and the thin film layer 2 described above, an anchor coat layer, a barrier coat film, a first sealant layer, a second sealant layer, a support layer, a barrier layer, a paper layer, It may have other layers such as a printing layer. These other layers can be laminated on each other via the adhesive layer by the dry lamination method or via the adhesive resin layer by the melt extrusion lamination method. Hereinafter, each layer will be described.

[Surface modification of polyester resin layer by plasma]
It is possible to perform surface modification by plasma by applying plasma generated in a vacuum environment to the surface of the polyester resin layer 1 by using argon, oxygen, nitrogen, carbon dioxide gas, or a mixed gas thereof. it can. By performing the surface modification with the plasma on the polyester resin layer 1, the adhesion between the thin film layer 2 and the polyester resin layer 1 can be improved.

[Anchor coat layer]
The anchor coat layer may be provided between the polyester resin layer 1 and the thin film layer 2. As a result, the adhesion strength between the polyester resin layer and the thin film layer can be increased, and delamination after hot water sterilization can be prevented.

For such a purpose, the anchor coating agent that can be used in the present invention is an anchor coating made of any resin having a heat resistant temperature of 135° C. or higher, for example, vinyl-modified resin, epoxy resin, urethane resin, polyester resin, or the like. Examples of the agent include an anchor coating agent composed of a polyacrylic or polymethacrylic resin having two or more hydroxyl groups in the structure and an isocyanate compound as a curing agent. In addition, a silane coupling agent may be used in combination therewith as an additive, and nitrified cotton may be used in combination for increasing heat resistance.

The anchor coat layer is formed by coating the above-mentioned anchor coating agent by a known coating method such as roll coating, gravure coating, knife coating, dip coating, spray coating, etc., drying and removing the solvent, diluent, etc., and curing. Can be formed. The thickness of the anchor coat layer is preferably about 0.2 to 0.3 μm.

[Barrier coat film]
The barrier coat film 3 is preferably provided on the thin film layer 2. Thereby, the gas barrier property can be further improved. As such a barrier coat, a composition containing at least one kind of alkoxide represented by the general formula: R ¹ _n M(OR ² ) _m , polyvinyl alcohol and/or ethylene vinyl alcohol is prepared by a sol-gel method. The thing by the composition for barrier coats obtained by condensation can be used conveniently. Further, a silane coupling agent can be added.

The alkoxide that can be preferably used in the barrier coat film is represented by the general formula: R ¹ _n M(OR ² ) _m (wherein R ¹ and R ² are organic groups having 1 to 8 carbon atoms, M is a metal atom, and n is a metal atom). Is an integer of 0 or more, m is an integer of 1 or more, and n+m is a valence of M), and at least one or more of a partial hydrolyzate of the alkoxide or a hydrolytic condensate of the alkoxide is Can be used. The partial hydrolyzate of the above alkoxide does not need to have all the alkoxy groups hydrolyzed, and may have one or more hydrolyzed, or a mixture thereof. The hydrolyzed condensate represents a dimer or more of partially hydrolyzed alkoxide, and a dimer or hexamer is usually used.

The barrier coat film 3 can be formed by coating the thin film layer 2 with the above-mentioned barrier coat composition by a conventional method and drying it. As a method for applying the barrier coat film, for example, a roll coater such as a gravure coater, a spray coater, a spin coater, a dipping coat, a brush, a bar code, an applicator, or other coating means is used to dry the coat once or a plurality of times. A barrier coat having a film thickness of 0.01 μm to 30 μm, preferably 0.1 μm to 10 μm can be formed. If necessary, a primer agent or the like can be applied on the thin film layer 2 in advance when applying the barrier coat film.

In the present invention, after the thin film layer 2 and the barrier coat film 3 are provided on the polyester resin layer 1, a thin film layer may be further provided, and the barrier coat film may be formed on the thin film layer in the same manner as above. .. By increasing the number of stacked layers in this way, the gas barrier property can be further improved.

[First sealant layer]
The first sealant layer is the innermost layer side when it is used as a package. The sealant layer is a layer formed of a heat-sealable resin that can be fused to each other by heat. The first sealant layer may include a fossil fuel-derived resin material or a biomass-derived resin material.

The resin material forming the first sealant layer is not particularly limited as long as it is a resin that can be mutually fused by heat, and specifically, for example, low density polyethylene (LDPE), medium density polyethylene (MDPE). ), high-density polyethylene (HDPE), linear (linear) low-density polyethylene (LLDPE), ethylene-α-olefin copolymer polymerized using a metallocene catalyst, ethylene-polypropylene random or block copolymer , Polypropylene, ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene- Methyl methacrylate copolymer (EMMA), ionomer resin, heat-sealable ethylene/vinyl alcohol resin, or copolymer resin methylpentene resin, ethylene-propylene copolymer, methylpentene polymer, polybutene polymer, polyethylene, polypropylene Or polyolefin resin such as cyclic olefin copolymer, acid-modified polyolefin resin obtained by modifying polyolefin resin with unsaturated carboxylic acid such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, polyvinyl acetate resin Examples thereof include resins, poly(meth)acrylic resins, polyvinyl chloride resins, and other resins. These may be used alone or as a mixture of two or more kinds. The sealant layer can be used as a resin film or sheet as described above, or a coating film thereof.

When polyethylene is used as the resin material forming the first sealant layer, as a raw material thereof, in addition to ethylene obtained from fossil fuel, a polymer of ethylene derived from biomass may be used. As the biomass-derived ethylene, specifically, for example, those described in JP2012-251006A can be used. By using polyethylene obtained by polymerizing biomass-derived ethylene as a material forming the first sealant layer, a layer made of a carbon-neutral material can be formed. Further, the amount of fossil fuel used can be reduced, and the environmental load can be reduced.

Commercially available ethylene may be used as the biomass-derived ethylene, for example, a straight chain derived from sugar cane of “C4LL-LL118 (d=0.916, MFR=1.0 g/10 min)” manufactured by Braschem. A low-density polyethylene-based resin or a sugarcane-derived low-density polyethylene-based resin of “SBC118 (d=0.918, MFR=8.1 g/10 min)” can be used.

Although the first sealant layer is a single layer in the present embodiment, two or more first sealant layers may be provided. When two or more first sealant layers are provided, they may have the same composition or different compositions. For example, the sealant layer 2 is composed of three layers in which a first layer, a second layer and a third layer are sequentially laminated, and the first layer and the third layer are made of a fossil fuel-derived resin material, The second layer may be a resin material containing a resin material derived from biomass. When the sealant layer 2 is composed of two or more layers, they can be laminated using a co-extrusion method.

The thickness of the first sealant layer is preferably 20 to 200 μm, more preferably 30 to 130 μm.

Examples of the method for laminating the first sealant layer on one surface (inner surface side) of the laminate include a dry lamination method and a melt extrusion lamination method. When performing the above-mentioned lamination, the film can be subjected to a pretreatment such as corona treatment, ozone treatment, flame treatment, or the like, if necessary. Among them, the dry lamination method is more preferable because it has excellent adhesive strength.

[Second sealant layer]
The second sealant layer is the outermost layer when used as a package. The second sealant layer is a layer formed of a heat-sealable resin that can be fused to each other by heat. The second sealant layer can use the same material as the first sealant layer 3.

[Support layer]
The support layer is not particularly limited as long as it can support the laminate and improve the strength properties and impact resistance of the laminate. The support layer may include a resin material derived from fossil fuel or a resin material derived from biomass. Examples of the resin material forming the support layer 3 include polyesters such as polyethylene terephthalate and polybutylene terephthalate, and polyamides such as polypropylene and nylon. Further, the support layer is preferably stretched, and more preferably biaxially stretched. As the support layer, one of these layers may be used alone, or two or more layers may be used in combination.

As the polyester that can be used as the material forming the support layer, in addition to conventionally known polyester derived from fossil fuel, polyester derived from biomass can be used. Further, the polyester may be a mixture of a resin material containing a conventional fossil fuel-derived raw material and a resin material containing a biomass-derived raw material.

In order to improve the adhesiveness between the support layer and the first sealant layer, a layer made of a modified polyolefin resin made of a modified polyolefin may be provided between the support layer and the first sealant layer. .. Modified polyolefins are modified by substituting a part of the main component polyolefin with another substance (monomer) by copolymerization or cocondensation, or by locally reacting an appropriate substance (monomer). It is a polyolefin resin. Specifically, for example, low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear (linear) low density polyethylene (LLDPE), ethylene polymerized using a metallocene catalyst. -Α-olefin copolymer, polypropylene (PP), ethylene-vinyl acetate copolymer (EVA), ionomer resin, ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), Polyethylene resin such as ethylene-methacrylic acid copolymer (EMAA), ethylene-propylene copolymer, methylpentene polymer, polyethylene, polyethylene-based resin, or polypropylene-based resin, acrylic acid, methacrylic acid, maleic anhydride, Examples thereof include acid-modified polyolefin resins modified with fumaric acid and other unsaturated carboxylic acids. Needless to say, the above-mentioned polyethylene-based resin may be the one using the above-mentioned biomass-derived ethylene as a monomer unit.

A preferable modified polyolefin is a copolymer having a structure in which a polyolefin segment and a segment having a polarity other than olefin are bonded in a block shape and/or a graft shape and/or a random shape, and for example, a propylene-based polyolefin segment. And a copolymer of a segment containing lactic acid as a constituent, a copolymer of an ethylene-based polyolefin segment and a segment containing an acrylic acid unit as a constituent, with a propylene-based polyolefin segment and a segment containing a acrylic acid unit as a constituent Examples thereof include copolymers. Specifically, for example, as the maleic anhydride-modified polyolefin resin, Admer SE800, SF740, SF731, SF730 manufactured by Mitsui Chemicals, Inc. can be used.

In addition, polylactic acid may be used as the biomass-derived resin material forming the support layer, and for example, a polylactic acid film sold by Mitsui Chemicals Tohcello can be preferably used.

The thickness of the support layer is, for example, 5 to 100 μm and may be appropriately adjusted depending on the intended use of the laminate. For example, when the laminate is used as a packaging material for applications requiring rigidity, the support is The layer thickness may be increased.

In addition, by forming the support layer using a resin material containing a raw material derived from biomass, the support layer becomes a layer made of carbon neutral resin. Therefore, by using the polyester resin layer 1 together, the amount of fossil fuel used can be further reduced, and the environmental load can be reduced.

The support layer can be produced, for example, by an inflation method or a T-die method.

[Paper layer]
As the paper layer, any paper can be used depending on the desired rigidity and the like, for example, high-quality paper, imitation paper, art paper, coated paper, pure white roll paper, kraft paper, label paper with increased water resistance. It is possible to use known papers such as cup paper, card paper, ivory paper, paperboard such as Manila ball, milk carton base paper, cup base paper, synthetic paper and clay coated paper.

Before laminating another layer on the paper layer, the surface of the paper layer may be subjected to corona discharge treatment, frame treatment, or the like. By performing these treatments, the adhesive strength between layers can be improved. The corona discharge treatment can be performed by using a known corona discharge treatment device and passing the paper base material in the generated corona atmosphere. The frame treatment can be carried out by using a known frame treatment device and broiling the surface of the paper base material with fire.

The basis weight of the paper layer 1 is about 80 to 600 g/m ² , and preferably the basis weight is about 150 to 450 g/m ² .

[Print layer]
The printing layer can be provided as needed, and can be provided, for example, on the surface of the polyester resin layer 1 on the thin film layer 2 side or the outer surface of the paper layer. The print layer is a desired print pattern such as a character, a pattern, a figure, a symbol, or a pattern for displaying decoration, contents, shelf life, manufacturer, seller, etc. Is a layer that forms. The printing layer may be provided on the entire surface or may be provided on a part thereof.

[Adhesive layer]
The adhesive layer provided when the two layers are bonded by the dry lamination method can be formed by applying an adhesive layer on the surface of the layer to be laminated and drying it. As the adhesive, for example, one-component or two-component curing or non-curing vinyl type, (meth)acrylic type, polyamide type, polyester type, polyether type, polyurethane type, epoxy type, rubber type, etc. An adhesive such as a solvent type, an aqueous type, or an emulsion type can be used. As a method for coating the above-mentioned adhesive for lamination, for example, a direct gravure roll coating method, a gravure roll coating method, a kiss coating method, a reverse roll coating method, a Fonten method, a transfer roll coating method, or any other method is used to form a laminate. It can be applied to the coated side of the layer. The coating ^{amount, 0.1g / m 2 ~10g / m} 2 ( dry) are ^{preferred, 1g / m 2 ~5g / m} 2 ( dry) is more preferable.

The adhesive layer provided when the two layers are bonded by the melt extrusion lamination method is formed by the melt extrusion lamination method using an adhesive resin layer which is a thermoplastic resin. The thermoplastic resin that can be used for the adhesive resin layer includes a polyethylene resin, a polypropylene resin, or a cyclic polyolefin resin, or a copolymer resin containing these resins as a main component, a modified resin, or a mixture (including an alloy). ) Can be used. Examples of the polyolefin resin include low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear (linear) low density polyethylene (LLDPE), polypropylene (PP), metallocene catalyst. Ethylene-α-olefin copolymer, ethylene-polypropylene random or block copolymer, ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene Ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-maleic acid copolymer, ionomer resin, and adhesion between layers In order to improve the, the above-mentioned polyolefin resin, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, it is possible to use an acid-modified polyolefin resin modified with an unsaturated carboxylic acid such as itaconic acid. it can. In addition, a resin obtained by graft-polymerizing or copolymerizing an unsaturated carboxylic acid, an unsaturated carboxylic anhydride, or an ester monomer with a polyolefin resin can be used. These materials can be used alone or in combination of two or more. As the cyclic polyolefin-based resin, for example, an ethylene-propylene copolymer, a cyclic polyolefin such as polymethylpentene, polybutene, and polynorbornene can be used. These resins may be used alone or in combination of two or more. Needless to say, the above-mentioned polyethylene-based resin may be the one using the above-mentioned biomass-derived ethylene as a monomer unit. For example, in a laminated body in which a paper layer, an adhesive resin layer, a thin film layer 2, a polyester resin layer 1, and a first sealant layer are laminated in this order, when the thin film layer 2 contains a metal, the adhesive resin layer is replaced with ethylene-methacrylic acid copolymer. By using a polymer (EMAA), the adhesiveness between the paper layer and the thin film layer 2 can be improved.

The thickness of the adhesive resin layer can be appropriately set in the range of usually 5 to 800 μm, preferably 10 to 500 μm, and when it is thick, it may be a multilayer structure. If the thickness is less than this range, the moisture barrier property will be insufficient, and if it is more than this range, the quality will be excessive and the moldability will be deteriorated. When the adhesive layer is laminated on the surface of the polyester resin layer by a melt extrusion laminating method using a polyolefin resin having a polar group such as an acid-modified polyolefin resin as the adhesive layer, an anchor coat is used. The adhesive layer can be laminated without performing surface treatment with an agent or the like.

As described above, the laminate according to the present invention includes the polyester resin layer 1 and the thin film layer 2, and the polyester resin layer 1 is formed of a layer made of a carbon neutral material and contains isophthalic acid. There is. Therefore, the amount of fossil fuel used can be significantly reduced, and the environmental load can be reduced. It is also more flexible than conventional biopolyesters containing only terephthalic acid. Therefore, the generation of cracks can be suppressed in the specifications of the reference example described later.

[Use]
The laminate according to the present invention can be suitably used for applications such as a packaging bag, a paper container, a paper cup, various label materials, a lid material, a sheet molded product, and a laminated tube. As a packaging bag, for example, a standing pouch type, a side seal type, a two-side seal type, a three-side seal type, a four-side seal type, an envelope sticking seal type, a joint sticking seal type (pillow seal type), a pleated seal type, a flat bottom seal type. , Square bottom seal type, gusset type and the like. The thickness of the laminate in that case can be appropriately determined according to the application, and is used, for example, in the form of a film having a thickness of 30 to 300 μm, preferably 35 to 180 μm.

[Packing bag]
A case where the laminate according to the present invention is applied to a standing pouch will be described. FIG. 3 is a diagram schematically showing an example of the structure of the standing pouch. As shown in FIG. 3, the standing pouch 20 includes two body portions (side sheet) 21 and a bottom portion (bottom sheet) 22. In the standing pouch 20, a side sheet 21 and a bottom sheet 22 are made of the same material. The side sheet 21 and the bottom sheet 22 of the standing pouch 20 are formed using, for example, a laminated body 10A in which a polyester resin layer 1, a thin film layer 2, and a first sealant layer 4 are laminated in order as shown in FIG. be able to. In the present embodiment, the standing pouch 20 has the side sheet 21 and the bottom sheet 22 formed of the same member, but the present invention is not limited to this, and the side sheet 21 and the bottom sheet 22 are separate members. It may be composed of.

[Tube container]
Next, a case where a tube container is formed using the laminate according to the present invention will be described. FIG. 5 is a partial cross-sectional view schematically showing an example of the tube container. As shown in FIG. 5, the tube container 30 includes a head portion 31 and a tubular body portion 32. The head portion 31 includes a hollow conical shoulder portion 33 and a spout portion 34, which are integrally formed.

The tubular body 32 is connected to the shoulder 33 of the head 31. The tubular body portion 32 can be formed by using the laminated body 10B. FIG. 6 shows a partial cross-sectional view of the laminated body 10B forming the tubular body of the tube container. As shown in FIG. 6, the laminated body 10B forming the tubular body 32 is formed by laminating the second sealant layer 5, the polyester resin layer 1, the thin film layer 2, and the first sealant layer 4 in order. . The first sealant layer 4 is the innermost layer when it is used as a tube container, and the second sealant layer 5 is the outermost layer when it is used as a tube container.

[Paper container]
A case where a paper container is formed using the laminate according to the present invention will be described. The paper container uses, for example, as shown in FIG. 7, a laminate 10C in which a second sealant layer 5, a paper layer 6, a thin film layer 2, a polyester resin layer 1, and a first sealant layer 4 are sequentially laminated. Can be formed. The first sealant layer 4 is an innermost layer when used as a paper container, and the second sealant layer 5 is an outermost layer when used as a paper container. As shown in FIG. 8, the paper container 40 has a rectangular tube-shaped body portion 41 including a side surface, a rectangular plate-shaped bottom portion 42, and an upper portion 43, and is a so-called gobel top type container. ..

The upper portion 43 has a pair of inclined plates 44 facing each other and a pair of folding portions 45 located between the inclined plates 44 and folded between the inclined plates 44. In addition, the pair of inclined plates 44 are adhered to each other by a margin 46 provided at the upper end of each. The spout may be attached to one of the pair of slant plates 44 and the spout may be sealed with a cap. The paper container 40 can be used as a liquid paper container, for example. Moreover, you may form a flat top type container using 10 C of laminated bodies.

[Paper cup]
A case where a paper cup is formed using the laminate according to the present invention will be described. The paper cup can be formed by using, for example, as shown in FIG. 9, a laminated body 10D in which a paper layer 6, a thin film layer 2, a polyester resin layer 1, and a first sealant layer 4 are laminated in order. FIG. 10 is a perspective view in which a part of the paper cup is cut off. As shown in FIG. 10, the paper cup 50 is provided at the lower end (one end) of a cylindrical body portion 52 having a flange portion 51 at the upper portion and having a diameter gradually increasing toward the opening portion. And a bottom portion 53. The body portion 52 is provided with a flange portion 51 whose upper end is rounded outward. It should be noted that the paper cup 50 is sealed by accommodating the contents and then adhering a lid member (not shown) along the flange portion 51 of the body portion 52. The lid material preferably has a gas barrier property.

Further, the paper cup 50 may include an exterior body 54 on the outer periphery of the body portion 52, as shown in FIG. 11. As the exterior body 54, for example, paper can be used. A convex portion 55 is formed on the body portion 52. The convex portion 55 is formed to provide a gap 56 of an air layer between the body portion 52 and the exterior body 54. One or more convex portions 55 are provided in the horizontal direction, and for example, two convex portions 55 can be provided as shown in FIG.

[Evaluation of flexibility]
Here, the results of evaluating the flexibility using the laminate including the polyester resin 1 are shown.
Other aspects
Another object of the present invention is to provide a laminate in which a polyester resin layer containing biomass polyester and a thin film layer are laminated, and the flexibility can be improved.
The laminate according to the present invention is a laminate in which at least a polyester resin layer and a thin film layer containing at least one of an inorganic substance and an inorganic oxide are laminated,
The polyester resin layer comprises a biomass polyester resin having a biomass-derived ethylene glycol as a diol unit and a fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit,
The dicarboxylic acid may contain terephthalic acid and isophthalic acid.
In the present invention, at least the polyester resin layer, the thin film layer, and the barrier coat film may be laminated in this order.
In the present invention, it may be a laminate in which paper layers are further laminated.
Further, in the present invention, the first and/or second sealant layer contains a resin material derived from fossil fuel or biomass, and the resin material is selected from the group consisting of polyethylene, polypropylene, and polylactic acid. It may contain a resin.
According to the present invention, in a laminate having a polyester resin layer containing a biomass polyester resin having a biomass-derived ethylene glycol as a diol unit and a fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit, isophthalic acid is used as a dicarboxylic acid component. By including it, it is possible to realize a laminate that can improve flexibility.

<Reference example 1>
<Production of Laminate 1>
Fossil fuel-derived terephthalic acid, fossil fuel-derived isophthalic acid, biomass-derived ethylene glycol (biomass polyester), and fossil fuel-derived terephthalic acid and fossil fuel-derived ethylene glycol (fossil fuel polyester) A biaxially stretched polyester film 1 having a thickness of 12 μm was prepared. The polyester film 1 had a biomass-derived carbon content of 20% as measured by radiocarbon (C14). Further, the content of isophthalic acid is 2.0 mol% with respect to all the dicarboxylic acid units constituting the biomass polyester, and the content of isophthalic acid in the polyester film 1 is equal to the total dicarboxylic acid constituting the polyester film 1. It was 1.33 mol% with respect to the unit.

One surface of the polyester film 1 was subjected to corona treatment, and a printed layer (pattern) was formed on the corona-treated surface. Next, using a sand laminating method, the printed surface of the polyester film 1 and the aluminum foil (thickness 7 μm) were passed through fossil fuel-derived low-density polyethylene (density 0.920 g/m ³ , thickness 15 μm). Pasted together. Further, the aluminum foil and a low-density polyethylene film derived from fossil fuel (density 0.920 g/m ³ , thickness 40 μm) were combined with a low-density polyethylene derived from fossil fuel (density 0.920 g using a sand laminating method). /M ³ , thickness 15 μm) to obtain a laminate 1 in which a polyester film 1, a printing layer, a low-density polyethylene, an aluminum foil, a low-density polyethylene, and a low-density polyethylene film are laminated in this order.

<Reference example 2>
<Preparation of laminated body 2>
Biaxial film having a thickness of 12 μm formed using terephthalic acid derived from fossil fuel and ethylene glycol derived from biomass (biomass polyester), and terephthalic acid derived from fossil fuel and ethylene glycol derived from fossil fuel (fossil fuel polyester) A stretched polyester film 2 was prepared. The polyester film 2 had a biomass-derived carbon content of 20% as measured by radiocarbon (C14).

A polyester film 1, a printing layer, a low-density polyethylene, an aluminum foil, a low-density polyethylene, and a low-density polyethylene film were produced in the same manner as in Reference Example 1 except that the polyester film 2 was used instead of the polyester film 1. A laminated body 2 laminated in order was obtained.

<Flexibility evaluation>
Using the laminates 1 and 2, the flexibility (loop stiffness) of the polyester films 1 and 2 was evaluated. The evaluation results are shown in Table 1. Here, the MD direction refers to the transport direction of the biomass polyester film, and the TD direction refers to the direction orthogonal to the MD direction. Flexibility was evaluated as follows. First, the sample was cut into a width of 15 mm and a length of 165 mm to obtain test pieces. Then, the waist strength value (mN/15 mm) of each laminate was measured using a loop stiffener tester (manufactured by Tester Sangyo Co., Ltd.) with a loop length of 60 mm for this test piece.

This result shows that the polyester film 1 is softer. From this result, it can be expected that the polyester film 1 is less likely to crack in the thin film layer than the polyester film 2.

[Crack evaluation]
Next, the results of evaluating the occurrence of cracks using the laminate including the polyester resin 1 are shown.

<Reference example 3>
<Production of Laminate 3>
First, using a sand laminating method, one surface of the polyester film 1 and a low density polyethylene film derived from fossil fuel (density 0.920 g/m ³ , thickness: 40 μm) were formed into a low density polyethylene derived from fossil fuel. (Density 0.920 g/m ³ , thickness 15 μm) was used for bonding. Next, the other surface of the polyester film 1 and the aluminum foil (thickness 7 μm) were attached to each other using a dry laminating method. Further, a low density polyethylene derived from fossil fuel (density: 0.920 g/m ³ , thickness: 20 μm) was laminated on one surface of paper (basis weight: 400 g/m ² ) by using an extrusion laminating method. Finally, the aluminum foil and the other surface of the paper (basis weight of 400 g/m ² ) were bonded to each other via a fossil-fuel-derived ethylene methacrylate (EMAA, thickness 20 μm) using a sand laminating method. A low-density polyethylene, a paper, an ethylene methacrylate, an aluminum foil, a polyester film 1, a low-density polyethylene, and a low-density polyethylene film were sequentially laminated to obtain a laminate 3.

<Reference Example 4>
<Production of Laminate 4>
Low density polyethylene, paper, ethylene methacrylate, aluminum foil, polyester film 2, low density polyethylene, low density polyethylene were prepared in the same manner as in Reference Example 3 except that the polyester film 2 was used instead of the polyester film 1. A laminate 4 in which films were laminated in order was obtained.

<Crack evaluation>
By pressing with a male die and a female die, the laminated body 3 and the laminated body 4 were subjected to ruled line processing and punched into a blank for a paper container. After that, while containing the alcohol solution, the blank was made in the paper container shown in FIG. 8 so that the surface of the low-density polyethylene film was the inner surface, and corrosion of the aluminum foil after one week was visually observed. In the laminate 3, no corrosion of the aluminum foil was observed. On the other hand, in the laminate 4 using the polyester film 2, corrosion of the aluminum foil was observed. This shows that as a result of the occurrence of cracks in the polyester film 4 due to the ruled line processing, the alcohol solution passed through the polyester film 4 and reached the aluminum foil from the surface of the low density polyethylene film. From these results, it can be expected that the polyester film 1 is less likely to cause cracks in the thin film layer than the polyester film 2.

<Example 1>
<Production of laminated body 5>
Fossil fuel-derived terephthalic acid, fossil fuel-derived isophthalic acid, biomass-derived ethylene glycol (biomass polyester), and fossil fuel-derived terephthalic acid and fossil fuel-derived ethylene glycol (fossil fuel polyester) A biaxially stretched polyester film 1 having a thickness of 12 μm was prepared. The polyester film 1 had a biomass-derived carbon content of 20% as measured by radiocarbon (C14). Further, the content of isophthalic acid is 2.0 mol% with respect to all the dicarboxylic acid units constituting the biomass polyester, and the content of isophthalic acid in the polyester film 1 is equal to the total dicarboxylic acid constituting the polyester film 1. It was 1.33 mol% with respect to the unit.

An anchor coat agent was applied to the polyester film 1 and dried to form an anchor coat layer having a thickness of 0.3 μm. The anchor coating agent is prepared by mixing 1 part by weight of nitrified cotton and 5 parts by weight of acrylic polyol in a dilute solvent of methyl ethyl ketone (MEK)/ethyl acetate 1:1 and stirring, and from isophorone diisocyanate (IPDI). Was prepared so that the NCO groups would be equivalent to the OH groups of the main agent. Then, after aging at 40° C. for 48 hours, a thin film layer of aluminum oxide having a thickness of 200 Å was laminated by a vacuum vapor deposition method using an electron beam (EB) heating system under the vapor deposition conditions shown below. The cooling drum temperature at this time was -15 degreeC.
(Deposition conditions)
・Degree of vacuum in vapor deposition chamber: 2×10 ⁻⁴ mbar
・The degree of vacuum in the winding chamber: 2×10 ^-2 mbar
・Electron beam power: 25 kw
・Film transport speed: 480 m/min
・Deposition surface: Corona treatment

Then, a composition for forming a barrier coat having the following composition was applied onto the formed vapor deposition film by a gravure roll coating method, and then heat-treated at 180° C. for 60 seconds to give a thickness of 0.3 μm (dry). The barrier coat film (state) was formed to obtain a laminate 5 in which the polyester film 1, the aluminum oxide thin film layer, and the barrier coat film were laminated in this order.

(Preparation method)
To the prepared mixed solution of polyvinyl alcohol of composition a, isopropyl alcohol and ion-exchanged water was added the previously prepared hydrolyzed solution of composition b of ethyl silicate, silane coupling agent, hydrochloric acid, isopropyl alcohol and ion-exchanged water. And stirred to obtain a colorless transparent composition for forming a barrier coat.

<Barrier property evaluation>
Using the above-mentioned laminated body 5, the barrier property was evaluated as follows. The evaluation results are shown in Table 2. In addition, each measurement was performed at four points of Samples 1 to 4.
(Measurement of water vapor permeability)
The water vapor permeability was measured under the conditions of a temperature of 40° C. and a humidity of 90% RH by using a water vapor permeability measuring device (PERMATRAN, manufactured by MOCON). A water vapor permeability of 2.0 or less was evaluated as good.
(Measurement of oxygen permeability)
The oxygen permeability was measured under the conditions of a temperature of 23° C. and a humidity of 90% RH using an oxygen permeability measuring device (OX-TRAN, manufactured by MOCON). The case where the oxygen permeability was 1.0 or less was evaluated as good.

<Example 2>
<Production of Laminate 6>
Fossil fuel-derived low-density polyethylene (density 0.920 g/m ³ , thickness 40 μm) was extruded at 320° C. on the surface of the laminate 5 on which the barrier coat film was provided to form a sealant layer, A laminate 6 was obtained in which the polyester film 1, the thin film layer of aluminum oxide, the barrier coat film, and the low-density polyethylene were laminated in this order. Then, using the laminate 6 as the side sheet 21 and the bottom sheet 22, the standing pouch shown in FIG. 3 was produced.

<Example 3>
<Production of laminated body 7>
Instead of fossil fuel-derived low-density polyethylene (density 0.920 g/m ³ , thickness 40 μm), biomass-derived low-density polyethylene (Brasschem SBC118, density 0.918 g/m ³ , thickness 40 μm) is used. A laminate 7 was prepared in the same manner as in Example 2 except that the polyester film 1, the aluminum oxide thin film layer, the barrier coat film, and the low-density polyethylene were laminated in this order. Then, using the laminate 7 as the side sheet 21 and the bottom sheet 22, the standing pouch shown in FIG. 3 was produced.

<Example 4>
<Preparation of laminated body 8>
Using a dry laminating method, the surface of the laminate 5 on which the barrier coat film is provided and the linear low-density polyethylene film derived from fossil fuel (density 0.916 g/m ³ , thickness 130 μm) are attached. It matched. Next, using a dry laminating method, a linear low-density polyethylene film derived from fossil fuel and the surface of the laminate on the side where the barrier coat film is not provided (density 0.916 g/m ³ , thickness 130 μm) Were bonded together to obtain a laminate 8 in which a linear low-density polyethylene film, a barrier coat film, an aluminum oxide thin film layer, a polyester film 1, and a linear low-density polyethylene film were laminated in this order. Then, the laminated body 8 was used as the tubular body portion 32 so that the linear low-density polyethylene film adjacent to the polyester film 1 was the inner surface, and the tube container shown in FIG. 5 was produced.

<Example 5>
<Preparation of laminated body 9>
A linear low-density polyethylene derived from biomass instead of the fossil fuel-derived linear low-density polyethylene film (density 0.916 g/m ³ , thickness 130 μm) adjacent to the polyester film 1 (manufactured by Braschem, SLL118, density) 0.916 g/m ³ , thickness 130 μm) was prepared in the same manner as in Example 4 to prepare a linear low-density polyethylene film, a barrier coat film, a thin film layer of aluminum oxide, a polyester film 1, and a straight film. A laminated body 9 in which chain-like low-density polyethylene films were laminated in order was obtained. Then, the laminated body 9 was used as the tubular body portion 32 so that the linear low-density polyethylene film adjacent to the polyester film 1 was the inner surface, and the tube container shown in FIG. 5 was produced.

<Example 6>
<Production of Laminate 10>
Using the sand laminating method, the surface of the laminate 5 on the side where the barrier coat film is not provided and the low density polyethylene film derived from fossil fuel (density 0.920 g/m ³ , thickness 40 μm) are fossilized. Lamination was performed via low density polyethylene derived from fuel (density 0.920 g/m ³ , thickness 15 μm). Further, a low density polyethylene derived from fossil fuel (density: 0.920 g/m ³ , thickness: 20 μm) was laminated on one surface of paper (basis weight: 400 g/m ² ) by using an extrusion laminating method. Finally, using a sand laminating method, the surface of the laminated body 5 on which the barrier coat film is provided and the other surface of the paper (basis weight of 400 g/m ² ) are formed into a low density polyethylene derived from fossil fuel ( The density is 0.920 g/m ³ , the thickness is 15 μm), and low density polyethylene, paper, low density polyethylene, barrier coat film, aluminum oxide thin film layer, polyester film 1, low density polyethylene, low density A laminate 10 in which polyethylene films were laminated in order was obtained. Then, the laminated body 10 is subjected to ruled line processing by pressing it with a male die and a female die, and after punching into a blank for a paper container, the surface of the low density polyethylene film is made the inner surface, as shown in FIG. A paper container was produced.

<Example 7>
<Preparation of laminated body 11>
Instead of fossil fuel-derived low-density polyethylene film (density 0.920 g/m ³ , thickness 40 μm), biomass-derived low-density polyethylene (manufactured by Braschem, SBC118, density 0.918 g/m ³ , thickness 40 μm) was used. Except that it was used, it was prepared in the same manner as in Example 6, and low-density polyethylene, paper, low-density polyethylene, barrier coat film, aluminum oxide thin film layer, polyester film 1, low-density polyethylene, and low-density polyethylene film were laminated in this order. The laminated body 11 thus obtained was obtained. Then, the laminated body 11 is subjected to ruled line processing by pressing with a male die and a female die, and after punching into a blank for a paper container, the surface of the low density polyethylene film is made to be the inner surface, as shown in FIG. A paper container was produced.

<Example 8>
<Production of Laminate 12>
Fossil fuel-derived low-density polyethylene (density: 0.920 g/m ³ , thickness: 40 μm) was laminated on the surface of the laminate 5 on which the barrier coat film was not provided, by using an extrusion laminating method. Next, by using a sand laminating method, the paper (basis weight: 270 g/m ² ) and the surface of the laminate 5 on the side where the barrier coat film was provided were treated with fossil fuel-derived low-density polyethylene (density: 0. 920 g/m ³ , thickness of 15 μm) to obtain a laminate 12 in which paper, low-density polyethylene, barrier coat film, aluminum oxide thin film layer, polyester film 1, and low-density polyethylene are laminated in this order. It was In addition, a printing layer was formed on paper (basis weight: 250 g/m ² ). Then, after forming the body portion 52 and the bottom portion 53 using the laminated body 12, the paper having the printing layer provided on the outer periphery of the body portion 52 is wound so that the printing layer is on the outside, so that the paper cup shown in FIG. 11 is obtained. It was made.

<Example 9>
<Production of Laminate 13>
Fossil fuel-derived low-density polyethylene (density 0.920 g/m ³ , thickness 40 μm) in place of the innermost layer, biomass-derived low-density polyethylene (Brasschem SBC118, density 0.918 g/m ³ , thickness 40 μm) Was prepared in the same manner as in Example 8 except that (1) was used to obtain a laminate 13 in which paper, low-density polyethylene, barrier coat film, aluminum oxide thin film layer, polyester film 1, and low-density polyethylene were laminated in this order. It was In addition, a printing layer was formed on paper (basis weight: 250 g/m ² ). Then, after forming the body portion 52 and the bottom portion 53 by using the laminated body 13, the paper having the printing layer on the outer periphery of the body portion 52 is wound so that the printing layer is on the outside, so that the paper cup shown in FIG. 11 is obtained. It was made.

DESCRIPTION OF SYMBOLS 1 Polyester resin layer 2 Thin film layer 3 Barrier coat film 4 First sealant layer 5 Second sealant layer 6 Paper layer 10, 10A, 10B, 10C, 10D Laminated body 20 Standing pouch 30 Tube container 40 Liquid paper container 50 Paper cup

Claims (2)

At least a second sealant layer, a paper layer, a polyester resin layer having a thin film layer containing at least one of an inorganic substance and/or an inorganic oxide on one surface, and a first sealant layer, in that order. A paper container that includes a laminated body and has a ruled line ,
The polyester resin layer is a biaxially stretched film containing a biomass polyester resin containing ethylene glycol derived from biomass as a diol unit and dicarboxylic acid derived from fossil fuel as a dicarboxylic acid unit,
The dicarboxylic acid contains terephthalic acid and isophthalic acid,
The paper container , wherein the content of the isophthalic acid is 2.5 mol% or less based on all dicarboxylic acid units constituting the biomass polyester resin. The first and/or second sealant layer comprises a fossil fuel-derived or biomass-derived resin material, and the resin material comprises a resin selected from the group consisting of polyethylene, polypropylene, and polylactic acid. The paper container according to item 1 .

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