JP2019006082A - Laminate - Google Patents

Abstract

To provide a laminate that has an improved COreduction effect than a laminate composed of unrecycled polyethylene terephthalate, the laminate being good hygienically.SOLUTION: A laminate at least contains a substrate layer, a barrier layer, and a sealant layer in the stated order. The substrate layer contains polyethylene terephthalate having ethylene glycol as a diol unit, and terephthalic acid and isophthalic acid as dicarboxylic acid units. The barrier layer contains a metal foil.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laminate, and more particularly, to a laminate using a recycled polyester resin recovered from a packaging material or the like so that it can be used again as a raw material.

  In the production of packaging materials for filling products such as pharmaceuticals, cosmetics, and foods, plastics, which are materials derived from fossil fuels, are mainly used from the viewpoints of ease of molding and cost. As plastic materials widely used as materials for packaging containers, polyester resins, polyolefin resins, polyamide resins, and the like are used. Among these, 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.

  The polyester is obtained by polycondensation of a diol unit and a dicarboxylic acid unit. For example, polyethylene terephthalate (hereinafter sometimes abbreviated as PET) is produced by subjecting ethylene glycol and terephthalic acid as raw materials to an esterification reaction between the two and then a 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 such fossil fuel-derived materials, there has been an increasing trend toward reducing CO ₂ emissions by reducing the use of fossil fuels for various purposes in consideration of the environment. As an attempt to reduce the use of such fossil fuels, a method has been proposed in which a polyester resin recovered from a used packaging material such as a PET bottle can be reused, and recycled as a recycled polyester to form a packaging material again ( For example, see Patent Documents 1 and 2). In Patent Documents 1 and 2, reduction of CO ₂ emissions is achieved by using, as a part of the packaging material, polyester that has been collected from used products formed from fossil fuel-derived polyester and can be reused. It has been proposed that

JP 2011-256328 A JP 2012-41463 A

  However, packaging materials using recycled PET recycled by mechanical recycling that pulverizes, cleans, and reuses recovered polyester resin products such as PET bottles are contaminated due to foreign matter adhering to the recycled PET. There is an impression that there may be a nation. For this reason, the packaging material manufactured using the laminated body which consists of recycled PET, especially the packaging material for filling goods, such as a foodstuff, exists in the condition where it is difficult to obtain the trust from consumers.

  An object of this invention is to provide the laminated body which can solve such a subject effectively.

  The present invention is a laminate comprising at least a base material layer, a barrier layer, and a sealant layer in this order. The base material layer has ethylene glycol as a diol unit, and terephthalic acid and isophthalic acid are dicarboxylic acids. The unit includes polyethylene terephthalate, and the barrier layer is a laminate including a metal foil.

  The present invention is a laminate comprising at least a base material layer, a barrier layer, and a sealant layer in this order. The base material layer has ethylene glycol as a diol unit, and terephthalic acid and isophthalic acid are dicarboxylic acids. The unit includes polyethylene terephthalate, and the barrier layer is a laminate including a vapor deposition film.

  In the laminate according to the present invention, the barrier layer may include a metal vapor deposition film.

  In the laminate according to the present invention, the barrier layer may include a transparent vapor deposition film.

  The present invention is a laminate comprising at least a base material layer, a barrier layer, and a sealant layer in this order. The base material layer has ethylene glycol as a diol unit, and terephthalic acid and isophthalic acid are dicarboxylic acids. The barrier layer is a laminate including a saponified ethylene-vinyl acetate copolymer, including polyethylene terephthalate as a unit.

  In the laminate according to the present invention, the content of isophthalic acid may be 0.5 mol% or more and 5.0 mol% or less with respect to all dicarboxylic acid units constituting the polyethylene terephthalate.

  In the laminate according to the present invention, the intrinsic viscosity of the polyethylene terephthalate may be 0.58 dl / g or more and 0.80 dl / g or less.

According to the present invention, it is possible than laminate of polyethylene terephthalate which is not recycled is excellent in CO ₂ reduction, to provide a laminate having excellent sanitary properties.

It is a schematic cross section which shows an example of the laminated body by this invention. It is a schematic cross section which shows an example of the laminated body by this invention. It is a schematic cross section which shows an example of the laminated body by this invention. It is a schematic cross section which shows an example of the laminated body by this invention. It is a schematic cross section which shows an example of the base material layer of the laminated body by this invention.

<Laminate>
The laminate according to the present invention includes at least a base material layer, a barrier layer, and a sealant layer in this order. The laminate may further include an adhesive layer, a printing layer, other layers, and the like. When the laminate includes two or more adhesive layers and other layers, each may have the same composition or a different composition.

  The laminate according to the present invention will be described with reference to the drawings. Examples of schematic cross-sectional views of the laminate according to the present invention are shown in FIGS. In the laminate 10 shown in FIG. 1, the barrier layer 12 includes at least a metal foil 121. In the laminate 20 shown in FIGS. 2 and 3, the barrier layer 22 includes at least a vapor deposition film 220. In the laminate 30 shown in FIG. 4, the barrier layer 32 includes at least a saponified product 321 of an ethylene-vinyl acetate copolymer.

  The laminated body 10 shown in FIG. 1 includes a base material layer 11, an adhesive layer 14, a barrier layer 12, an adhesive layer 15, and a sealant layer 13 in this order. In the packaging bag provided with the laminated body 10, the sealant layer 13 is located on the innermost surface.

  The laminated body 20 shown in FIG. 2 includes a base material layer 21, an adhesive layer 24, a film base material layer 221 of a vapor deposition film 220 constituting the barrier layer 22, and a vapor deposition layer of the vapor deposition film 220 constituting the barrier layer 22. 222, the gas barrier coating film 223 of the vapor deposition film 220 constituting the barrier layer 22, the adhesive layer 25, and the sealant layer 23 are provided in this order. In the packaging bag provided with the laminated body 20, the sealant layer 23 is located on the innermost surface.

  The laminate 20 shown in FIG. 3 includes a base material layer 21, an adhesive layer 24, a gas barrier coating film 223 of a vapor deposition film 220 constituting the barrier layer 22, and a vapor deposition layer of the vapor deposition film 220 constituting the barrier layer 22. 222, the film base layer 221 of the vapor deposition film 220 constituting the barrier layer 22, the adhesive layer 25, and the sealant layer 23 are provided in this order. In the packaging bag provided with the laminated body 20, the sealant layer 23 is located on the innermost surface.

  The laminate 30 shown in FIG. 4 includes a base material layer 31, an adhesive layer 34, a saponified product 321 of an ethylene-vinyl acetate copolymer constituting the barrier layer 32, an adhesive layer 35, and a sealant layer 33. Prepare in this order. In the packaging bag provided with the laminated body 30, the sealant layer 33 is located on the innermost surface.

  Hereinafter, each layer which comprises a laminated body is demonstrated.

[Base material layer]
The base material layer includes polyethylene terephthalate recycled by mechanical recycling (hereinafter, polyethylene terephthalate is also referred to as PET). Specifically, the base material layer includes PET obtained by recycling a PET bottle by mechanical recycling, and the PET has a diol unit of ethylene glycol and a dicarboxylic acid unit of terephthalic acid and isophthalic acid. Here, mechanical recycling generally means that collected polyethylene terephthalate resin products such as PET bottles are crushed and washed with alkali to remove dirt and foreign matter on the surface of PET resin products, and then dried for a certain period of time under high temperature and reduced pressure. In this method, contaminants remaining inside the PET resin are diffused and decontaminated to remove stains on the resin product made of the PET resin, and then returned to the PET resin again. Hereinafter, in this specification, polyethylene terephthalate obtained by recycling PET bottles is referred to as “recycled polyethylene terephthalate (hereinafter also referred to as recycled PET)”, and polyethylene terephthalate that is not recycled is referred to as “virgin polyethylene terephthalate (hereinafter referred to as virgin PET). ) ".

  Of the PET contained in the base material layer, the content of isophthalic acid is preferably 0.5 mol% or more and 5 mol% or less, based on all dicarboxylic acid units constituting the PET, and is 1.0 mol%. More preferably, it is 2.5 mol% or less. If the content of isophthalic acid is less than 0.5 mol%, flexibility may not be improved. On the other hand, if it exceeds 5 mol%, the melting point of PET may be lowered and heat resistance may be insufficient. The PET may be biomass PET as well as normal PET derived from fossil fuel. “Biomass PET” includes ethylene glycol derived from biomass as a diol unit and dicarboxylic acid derived from fossil fuel as a dicarboxylic acid unit. This biomass PET may be formed of only PET having biomass-derived ethylene glycol as a diol unit and fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit, or biomass-derived ethylene glycol and fossil fuel-derived diol. It may be formed of PET having a diol unit and a dicarboxylic acid unit derived from a fossil fuel-derived dicarboxylic acid.

  PET used for PET bottles can be obtained by a conventionally known method in which the above-described diol units and dicarboxylic acid units are polycondensed. Specifically, a general method of melt polymerization in which an esterification reaction and / or a transesterification reaction between the diol unit and the dicarboxylic acid unit is performed, and then a polycondensation reaction is performed under reduced pressure, or an organic solvent It can be produced by a known solution heating dehydration condensation method using

  The amount of the diol unit used in the production of the PET is substantially equimolar with respect to 100 mol of the dicarboxylic acid or derivative thereof, but in general, esterification and / or transesterification and / or condensation polymerization is generally used. Since there is distillation during the reaction, it is used in an excess of 0.1 mol% or more and 20 mol% or less.

  The polycondensation reaction is preferably performed in the presence of a polymerization catalyst. The addition timing of the polymerization catalyst is not particularly limited as long as it is before the polycondensation reaction, and it may be added when the raw materials are charged, or may be added at the start of pressure reduction.

  PET that has been recycled from PET bottles is polymerized and solidified as described above, and is further subjected to solid-phase polymerization as necessary in order to further increase the degree of polymerization or to remove oligomers such as cyclic trimers. You may go. Specifically, solid-phase polymerization is performed by making PET into chips and drying, followed by heating at a temperature of 100 ° C. or higher and 180 ° C. or lower for 1 to 8 hours to pre-crystallize the PET, followed by 190 ° C. It is performed by heating at a temperature of 230 ° C. or lower for 1 hour to several tens of hours in an inert gas atmosphere or under reduced pressure.

  The intrinsic viscosity of PET contained in the base material layer is preferably 0.58 dl / g or more and 0.80 dl / g or less. When the intrinsic viscosity is less than 0.58 dl / g, the mechanical properties required for the PET film as a substrate may be insufficient. On the other hand, when the intrinsic viscosity exceeds 0.80 dl / g, the productivity in the film forming process may be impaired. The intrinsic viscosity is measured at 35 ° C. with an orthochlorophenol solution.

  The base material layer preferably contains 50% by weight or more and 95% by weight or less of recycled PET, and may contain virgin PET in addition to recycled PET. The virgin PET may be a PET in which the diol unit as described above is ethylene glycol, the dicarboxylic acid unit includes terephthalic acid and isophthalic acid, and the dicarboxylic acid unit does not include isophthalic acid. Also good. Moreover, the base material layer may contain polyesters other than PET. For example, as the dicarboxylic acid unit, in addition to aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid, aliphatic dicarboxylic acids and the like may be included.

  Specific examples of the aliphatic dicarboxylic acid include chains having usually 2 to 40 carbon atoms, such as oxalic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, dodecanedioic acid, dimer acid, and cyclohexanedicarboxylic acid. And alicyclic dicarboxylic acids. Examples of the aliphatic dicarboxylic acid derivatives include lower alkyl esters such as methyl esters, ethyl esters, propyl esters, and butyl esters of the aliphatic dicarboxylic acids, and cyclic acid anhydrides of the aliphatic dicarboxylic acids such as succinic anhydride. . Among these, as the aliphatic dicarboxylic acid, adipic acid, succinic acid, dimer acid or a mixture thereof is preferable, and those having succinic acid as a main component are particularly preferable. As the derivative of the aliphatic dicarboxylic acid, methyl esters of adipic acid and succinic acid, or a mixture thereof are more preferable.

  Such a base material layer composed of PET may be a single layer or a multilayer. As shown in FIG. 5, when the above-described recycled PET is used for the base material layer, the base material layer may include a first layer 51, a second layer 52, and a third layer 53. In this case, in the laminate, the third layer 53 of the base material layer is located on the sealant layer side. In this case, the second layer 52 is a layer composed only of recycled PET or a mixed layer of recycled PET and virgin PET, and the first layer 51 and the third layer 53 are layers composed only of virgin PET. It is preferable to do. Thus, by using only virgin PET for the first layer 51 and the third layer 53, it is possible to prevent the recycled PET from being exposed from the front surface or the back surface of the base material layer. For this reason, the sanitary property of a laminated body is securable. Further, the base material layer may be a base material layer provided with two layers of the second layer 52 and the third layer 53 without providing the first layer 51 shown in FIG. Furthermore, a base material layer is good also as a base material layer provided with two layers, the 1st layer 51 and the 2nd layer 52, without providing the 3rd layer 53 shown in FIG. Also in these cases, the second layer 52 is a layer composed only of recycled PET or a mixed layer of recycled PET and virgin PET, and the first layer 51 and the third layer 53 are layers composed only of virgin PET. It is preferable that

  When one layer is formed by mixing recycled PET and virgin PET, there are a method of supplying separately to a molding machine, a method of supplying after mixing by dry blending, and the like. Among these, from the viewpoint of easy operation, a method of mixing by dry blend is preferable.

  Various additives can be added to the PET constituting the base material layer within the range in which the properties are not impaired in the production process or after the production. Examples of additives include plasticizers, UV stabilizers, anti-coloring agents, matting agents, deodorants, flame retardants, weathering agents, antistatic agents, yarn friction reducing agents, mold release agents, antioxidants, and ions. Examples include exchange agents and coloring pigments. The additive is preferably added in an amount of 5% by mass or more and 50% by mass or less, and preferably 5% by mass or more and 20% by mass or less with respect to the entire resin composition including PET.

  The base material layer can be formed, for example, by forming a film by the T-die method using the above-described PET. Specifically, after drying the above-mentioned PET, it is supplied to a melt extruder heated to a temperature not lower than the melting point of PET (Tm) to Tm + 70 ° C. to melt the resin composition. A film can be formed by extruding into a sheet from a die such as the above, and rapidly solidifying the extruded sheet 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 depending on 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 difference in peripheral speed between two or more rolls. The longitudinal stretching is usually performed in a temperature range of 50 ° C. or more and 100 ° C. or less. Further, the ratio of the longitudinal stretching is preferably 2.5 times or more and 4.2 times or less, although it depends on the required characteristics of the film application. When the draw ratio is less than 2.5, the thickness unevenness of the PET film becomes large and it is difficult to obtain a good film.

  The longitudinally stretched film is successively subjected to the transverse stretching, heat setting, and thermal relaxation treatment steps to form a biaxially stretched film. The transverse stretching is usually performed in a temperature range of 50 ° C. or more and 100 ° C. or less. The transverse stretching ratio is preferably 2.5 times or more and 5.0 times or less, although it depends on the required characteristics of this application. If it is less than 2.5 times, the thickness unevenness of the film becomes large and it is difficult to obtain a good film, and if it exceeds 5.0 times, breakage tends to occur during film formation.

  A heat setting treatment is subsequently performed after the transverse stretching, and a preferable temperature range for heat setting is Tg + 70 to Tm-10 ° C. of PET. The heat setting time is preferably 1 second or more and 60 seconds or less. Furthermore, for applications that require a low thermal shrinkage rate, heat relaxation treatment may be performed as necessary.

The thickness of the PET film obtained as described above is arbitrary depending on its use, but is usually about 5 μm to 100 μm, preferably 5 μm to 25 μm. Further, the breaking strength of the PET film in the MD direction 5 kg / mm ² or more 40 kg / mm ² or less, in TD direction 5 kg / mm ² or more 35 kg / mm ² or less, also elongation at break 50 in the MD direction % To 350%, and 50% to 300% in the TD direction. Further, the shrinkage rate when left in a temperature environment of 150 ° C. for 30 minutes is 0.1% or more and 5% or less.

  The virgin PET may be fossil fuel polyethylene terephthalate (hereinafter also referred to as fossil fuel PET) or biomass PET. Here, “fossil fuel PET” is a diol derived from a fossil fuel-derived diol and a dicarboxylic acid derived from a fossil fuel derived from a dicarboxylic acid unit. The recycled PET may be obtained by recycling a PET resin product formed using fossil fuel PET, or may be obtained by recycling a PET resin product formed using biomass PET. There may be.

[Barrier layer]
Next, the barrier layer will be described.

{First configuration of barrier layer}
The barrier layer according to the first configuration includes a metal foil. As the metal foil constituting the barrier layer of the laminate shown in FIG. 1, a conventionally known metal foil can be used. Aluminum foil is preferred from the viewpoints of gas barrier properties that prevent transmission of oxygen gas, water vapor, and the like, and light shielding properties that prevent transmission of visible light, ultraviolet light, and the like. The thickness of the metal foil is, for example, 5 μm or more and 15 μm or less. By setting the thickness of the metal foil to 5 μm or more, even if foreign matter is attached to the recycled PET used for the base material layer in the packaging bag provided with the laminate, the foreign matter appears on the inner surface side of the barrier layer. It is possible to prevent problems that occur. For this reason, the hygiene of the contents can be ensured.

{Second configuration of barrier layer}
The barrier layer according to the second configuration includes a vapor deposition film. The vapor deposition film which comprises the barrier layer of the laminated body shown in FIG.2 and FIG.3 is a film base material layer, the vapor deposition layer provided on the film base material layer, and the gas barrier property coating provided on the vapor deposition layer Including a membrane.

(Film base material layer)
As the film substrate layer, for example, a uniaxial or biaxially stretched film of a thermoplastic resin film such as polyethylene terephthalate (PET), polypropylene (PP), or nylon (ONy) can be suitably used. Moreover, the film base material layer may have gas barrier property. In this case, the gas barrier property as the whole laminate is improved, and in the packaging bag made from this laminate, for example, the permeation of oxygen from the outside can be suppressed, and deterioration due to oxidation of the contents can be suppressed. As an example, a film having a gas barrier property, such as a film having a high gas barrier property, such as a saponified ethylene-vinyl acetate copolymer (EVOH), a polyvinylidene chloride resin (PVDC), or the like may be used. Good. The thickness of the film base layer is, for example, 5 μm or more and 30 μm or less. When the thickness of the film substrate layer is less than 5 μm, the fracture strength and tensile strength are low, and the vapor deposition processability may not be sufficient.

(Deposition layer)
A vapor deposition layer is a layer which consists of a vapor deposition film which can be formed by a conventionally well-known method. By providing a vapor deposition layer, the gas barrier property which prevents permeation | transmission of oxygen gas, water vapor | steam, etc. can be provided thru | or improved. In addition, the vapor deposition film which comprises a barrier layer may be provided with two or more vapor deposition layers. When two or more vapor deposition layers are provided, each may have the same composition or a different composition.

  The deposited film may be a metal deposited film made of a metal deposited film or a transparent deposited film made of an inorganic oxide deposited film.

  In the case where the barrier layer includes a metal vapor deposition film, in addition to the gas barrier property described above, a light shielding property that prevents transmission of visible light, ultraviolet light, and the like can be imparted or improved. Moreover, since a metallic luster can be provided to a packaging bag, designability can be improved. When the barrier layer includes a transparent vapor deposition film, it is possible to impart or improve gas barrier properties that prevent permeation of oxygen gas, water vapor, and the like while maintaining the permeability of the contents.

  As a metal vapor deposition film, for example, aluminum (Al), magnesium (Mg), tin (Sn), sodium (Na), titanium (Ti), lead (Pb), zirconium (Zr), yttrium (Y), gold ( A metal vapor deposition film such as Au) or chromium (Cr) can be used. In particular, for packaging bags, it is preferable to provide an aluminum vapor deposition film.

  The film thickness of the metal vapor deposition film varies depending on the type of metal used and the like, but for example, it is desirably selected and formed within a range of 50 to 2000 mm, preferably 100 to 1000 mm. More specifically, in the case of an aluminum vapor deposition film, the film thickness is 50 to 600 mm, more preferably 100 to 450 mm.

  As a transparent vapor deposition film, for example, silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B), titanium ( An evaporated film of an oxide such as Ti), lead (Pb), zirconium (Zr), or yttrium (Y) can be used. In particular, it is preferable to provide a vapor deposition film of aluminum oxide or silicon oxide for packaging bags.

Representation of the inorganic oxide, for _example, SiO X, as such AlO _X MO _X (In the formula, M represents an inorganic element, the value of X, varies each of an inorganic element range.) In expressed. As a range of the value of X, silicon (Si) is 0 to 2, aluminum (Al) is 0 to 1.5, magnesium (Mg) is 0 to 1, calcium (Ca) is 0 to 1, 0 to 0.5 for potassium (K), 0 to 2 for tin (Sn), 0 to 0.5 for sodium (Na), 0 to 1.5 for boron (B), titanium (Ti) Can take values ranging from 0 to 2, lead (Pb) from 0 to 2, zirconium (Zr) from 0 to 2, and yttrium (Y) from 0 to 1.5. In the above, when X = 0, it is a complete inorganic simple substance (pure substance) and is not transparent, and the upper limit of the range of X is a completely oxidized value. Silicon (Si) and aluminum (Al) are suitably used for the packaging material, silicon (Si) is in the range of 1.0 to 2.0, and aluminum (Al) is in the range of 0.5 to 1.5. Can be used.

  The film thickness of the transparent vapor-deposited film varies depending on the type of inorganic oxide to be used, but is preferably selected and formed, for example, in the range of 50 to 2000 mm, preferably 100 to 1000 mm. For example, in the case of a vapor-deposited film of aluminum oxide or silicon oxide, the film thickness is preferably 50 to 500 mm, more preferably 100 to 300 mm.

  A vapor deposition film can be formed in the base material layer etc. using the following formation methods. As a method for forming a vapor deposition film, for example, 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 thermochemical method, or the like. Examples thereof include a chemical vapor deposition method (chemical vapor deposition method, CVD method) such as a vapor phase growth method and a photochemical vapor deposition method.

(Gas barrier coating film)
If necessary, a gas barrier coating film may be provided on the vapor deposition layer. The gas barrier coating film is a coating film that functions as a layer that suppresses permeation of oxygen gas, water vapor, and the like. The gas barrier coating film has a general formula R ¹ _n M (OR ² ) _m (wherein R ¹ and R ² represent an organic group having 1 to 8 carbon atoms, M represents a metal atom, and n Represents an integer of 0 or more, m represents an integer of 1 or more, and n + m represents a valence of M.), at least one alkoxide represented by: It is obtained by a gas barrier composition containing an ethylene-vinyl alcohol copolymer and polycondensed by a sol-gel method in the presence of a sol-gel method catalyst, an acid, water, and an organic solvent.

As the alkoxide represented by the general formula R ¹ _n M (OR ² ) _m , at least one kind of a partial hydrolyzate of alkoxide and a condensate of hydrolysis of alkoxide can be used. Moreover, as a partial hydrolyzate of said alkoxide, all the alkoxy groups do not need to be hydrolyzed, The thing by which 1 or more was hydrolyzed, and its mixture may be sufficient. As a condensate of hydrolysis of alkoxide, a dimer or more of partially hydrolyzed alkoxide, specifically, a 2 to 6 mer is used.

In the alkoxide represented by the above general formula R ¹ _n M (OR ² ) _m , as the metal atom represented by M, silicon, zirconium, titanium, aluminum, and the like can be used. In the present embodiment, examples of preferable metals include silicon and titanium. In the present invention, alkoxides may be used alone or in combination of two or more different metal atom alkoxides in the same solution.

In the alkoxide represented by the above general formula R ¹ _n M (OR ² ) _m , specific examples of the organic group represented by R ¹ include, for example, a methyl group, an ethyl group, an n-propyl group, i Examples thereof include alkyl groups such as -propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, n-hexyl group, n-octyl group and others. In the alkoxide represented by the general formula R ¹ _n M (OR ² ) _m , specific examples of the organic group represented by R ² include, for example, a methyl group, an ethyl group, an n-propyl group, i -Propyl group, n-butyl group, sec-butyl group, and the like. These alkyl groups in the same molecule may be the same or different.

  When preparing the gas barrier composition, for example, a silane coupling agent may be added. As said silane coupling agent, known organic reactive group containing organoalkoxysilane can be used. In this embodiment, an organoalkoxysilane having an epoxy group is particularly preferably used. Specifically, for example, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β -(3,4-epoxycyclohexyl) ethyltrimethoxysilane or the like can be used. The above silane coupling agents may be used alone or in combination of two or more.

{Third configuration of barrier layer}
The barrier layer according to the third configuration includes a saponified product (EVOH) of an ethylene-vinyl acetate copolymer. As EVOH which comprises the barrier layer of the laminated body shown in FIG. 4, the thing as described in Unexamined-Japanese-Patent No. 2008-307847 can be used, for example. The thickness of the barrier layer according to the third configuration is preferably 5 μm or more and 40 μm or less, and more preferably 10 μm or more and 35 μm or less. By setting the thickness of the barrier layer to 5 μm or more, even if foreign matter adheres to the recycled PET used for the base material layer in the packaging bag including the laminate, the foreign matter is exposed on the inner surface side of the barrier layer. Can be prevented. For this reason, the hygiene of the contents can be ensured.

  Two or more barrier layers described above may be provided. When two or more barrier layers are provided, each may have the same composition or a different composition.

[Sealant layer]
The sealant layer is the innermost layer side when a package is used. The sealant layer is a layer formed of a thermoplastic resin that can be fused to each other by heat. The sealant layer may contain a fossil fuel-derived resin material or a biomass-derived resin material.

  The resin material forming the sealant layer is not particularly limited as long as it is a resin that can be fused to each other by heat. 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 Alcohol resin, or methylpentene resin, ethylene-propylene copolymer, methylpentene polymer, polybutene polymer, polyolefin resin such as polyethylene, polypropylene or cyclic olefin copolymer, polyolefin resin such as acrylic acid, methacrylic acid, maleic acid Resin such as acid-modified polyolefin resin modified with unsaturated carboxylic acid such as maleic anhydride, fumaric acid, itaconic acid, polyvinyl acetate resin, poly (meth) acrylic resin, polyvinyl chloride resin, etc. Can be mentioned. These may be used alone or as a mixture of two or more. 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 for forming the sealant layer, a raw material obtained by polymerizing ethylene derived from biomass in addition to ethylene obtained from fossil fuel may be used. Specifically, as the ethylene derived from biomass, for example, those described in JP 2012-251006 A can be used. By using polyethylene obtained by polymerizing ethylene derived from biomass as a material constituting the sealant layer, it can be formed with a layer made of a carbon neutral material. Can be reduced, and the environmental load can be reduced.

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

  In this embodiment, the sealant layer is a single layer, but two or more sealant layers may be provided. When two or more sealant layers are included, each may have the same composition or a different composition. For example, the sealant layer 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, and the second layer This layer may be a resin material containing a biomass-derived resin material. In addition, when comprising a sealant layer by two or more layers, it can laminate | stack using a coextrusion method.

  The thickness of the sealant layer is preferably 20 μm or more and 200 μm or less, and more preferably 30 μm or more and 130 μm or less.

[Adhesive layer]
The adhesive layer is a layer provided when two arbitrary layers are bonded, and can be provided, for example, between the base material layer and the barrier layer, or between the barrier layer and the sealant layer.

  When two layers are bonded by a dry laminating method, the adhesive layer can be an adhesive layer formed by applying an adhesive to the surface of the layer to be laminated and drying it. Examples of the adhesive include one-part or two-part cured or non-cured vinyl, (meth) acrylic, polyamide, polyester, polyether, polyurethane, epoxy, rubber, etc. An adhesive such as a solvent type, an aqueous type, or an emulsion type can be used. As a two-component curable adhesive, a cured product of a polyol and an isocyanate compound can be used. As a coating method of the adhesive for laminating, for example, direct gravure roll coating method, gravure roll coating method, kiss coating method, reverse roll coating method, fountain method, transfer roll coating method, and other methods can be used. .

  The adhesive layer may be an adhesive resin layer used when two layers are bonded by a sand lamination method. Examples of the thermoplastic resin that can be used for the adhesive resin layer include a polyethylene resin, a polypropylene resin, or a cyclic polyolefin resin, or a copolymer resin, a modified resin, or a mixture (including alloy) containing these resins as a main component. ) Can be used. Examples of polyolefin resins include low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear (linear) low density polyethylene (LLDPE), polypropylene (PP), and metallocene catalysts. 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 interlayer adhesion In order to improve the , It can be used acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and an acid-modified polyolefin resin modified with an unsaturated carboxylic acid such as itaconic acid. Further, a resin obtained by graft polymerization or copolymerization of an unsaturated carboxylic acid, an unsaturated carboxylic acid anhydride, or an ester monomer can be used as the polyolefin resin. These materials can be used alone or in combination of two or more. As the cyclic polyolefin-based resin, for example, cyclic polyolefins such as ethylene-propylene copolymer, polymethylpentene, polybutene, and polynorbornene can be used. These resins can be used alone or in combination. In addition, as said polyethylene-type resin, what used the above ethylene derived from biomass as a monomer unit can be used, and a biomass degree can further be improved.

  When the adhesive resin layer is laminated by the melt extrusion laminating method, an anchor coat layer formed by applying an anchor coat agent and drying it may be provided on the surface of the layer to be laminated. Examples of the anchor coating agent include an anchor coating agent made of any resin having a heat resistant temperature of 135 ° C. or higher, such as a vinyl-modified resin, an epoxy resin, a urethane resin, a polyester resin, or a polyethyleneimine. An anchor coating agent that is a cured product of a polyacrylic or polymethacrylic resin (polyol) having two or more hydroxyl groups and an isocyanate compound as a curing agent can be preferably used. Moreover, a silane coupling agent may be used in combination as an additive, and nitrified cotton may be used in combination in order to improve heat resistance.

  There may be one adhesive layer in the laminate, or two or more may be included. For example, when two adhesive layers are included in the laminate, one adhesive layer may be referred to as a first adhesive layer, and the other adhesive layer may be referred to as a second adhesive layer.

  The anchor coat layer after drying has a thickness of 0.1 μm or more and 1 μm or less, preferably 0.3 μm or more and 0.5 μm or less. The adhesive layer after drying has a thickness of 1 μm to 10 μm, preferably 2 μm to 5 μm. The adhesive resin layer preferably has a thickness of 5 μm to 50 μm, preferably 10 μm to 30 μm.

[Other layers]
The laminate according to the present invention may further include a printed layer or the like as another layer. The printed layer can be used to display decorations, contents, display of the best-before period, display of manufacturers, sellers, etc., and display of other characters and letters, numbers, pictures, figures, symbols, patterns, etc. It is a layer for forming a desired arbitrary printed pattern. A printing layer can be provided as needed, for example, can be provided between a base material layer and a barrier layer. The printing layer may be provided on the entire surface of the base material layer, or may be provided on a part thereof. A printing layer can be formed using a conventionally well-known pigment and dye, The formation method is not specifically limited.

  The printed layer preferably has a thickness of 0.1 μm to 10 μm, more preferably 1 μm to 5 μm, and still more preferably 1 μm to 3 μm.

<Method for producing laminate>
The manufacturing method of the laminated body by this invention is not specifically limited, It can manufacture using conventionally well-known methods, such as a dry lamination method.

  The laminate according to the present invention is provided with chemical functions, electrical functions, magnetic functions, mechanical functions, friction / abrasion / lubrication functions, optical functions, thermal functions, surface functions such as biocompatibility, etc. For the purpose, it is also possible to perform secondary processing. Examples of secondary processing include embossing, painting, adhesion, printing, metalizing (plating, etc.), machining, surface treatment (antistatic treatment, corona discharge treatment, plasma treatment, photochromism treatment, physical vapor deposition, chemical vapor deposition, Coating, etc.). Further, the laminate according to the present invention can be subjected to laminating processing (dry laminating or extrusion laminating), bag making processing, and other post-processing processing to produce a molded product.

  The said laminated body can be used for the packaging bag with which goods, such as a foodstuff, are filled, for example. For example, the above laminate is used, and the laminate is folded in two, or two laminates are prepared, and the surfaces of the sealant are opposed to each other, and the peripheral end portion thereof is, for example, a side seal type , Two-side seal type, three-side seal type, four-side seal type, envelope-attached seal type, joint-attached seal type (pillow seal type), pleated seal type, flat bottom seal type, square bottom seal type, gusset type, etc. Thus, various forms of packaging bags can be manufactured.

  In the above, as a heat sealing method, for example, a known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, and an ultrasonic seal can be used.

  Since the packaging bag has excellent hygiene while reducing the environmental load, it can be suitably used as a packaging bag for sealing and packaging foods and the like.

DESCRIPTION OF SYMBOLS 10 Laminated body 11 Base material layer 12 Barrier layer 13 Sealant layer 121 Metal foil 20 Laminated body 21 Base material layer 22 Barrier layer 23 Sealant layer 220 Deposition film 30 Laminated body 31 Base material layer 32 Barrier layer 33 Sealant layer 321 Ethylene-vinyl acetate Saponification of copolymer

Claims (7)

At least a laminate comprising a base material layer, a barrier layer, and a sealant layer in this order,
The base material layer includes polyethylene terephthalate having ethylene glycol as a diol unit and terephthalic acid and isophthalic acid as dicarboxylic acid units,
The said barrier layer is a laminated body containing metal foil. At least a laminate comprising a base material layer, a barrier layer, and a sealant layer in this order,
The base material layer includes polyethylene terephthalate having ethylene glycol as a diol unit and terephthalic acid and isophthalic acid as dicarboxylic acid units,
The said barrier layer is a laminated body containing a vapor deposition film.   The said barrier layer is a laminated body of Claim 2 containing a metal vapor deposition film.   The said barrier layer is a laminated body of Claim 2 containing a transparent vapor deposition film. At least a laminate comprising a base material layer, a barrier layer, and a sealant layer in this order,
The base material layer includes polyethylene terephthalate having ethylene glycol as a diol unit and terephthalic acid and isophthalic acid as dicarboxylic acid units,
The barrier layer is a laminate including a saponified ethylene-vinyl acetate copolymer.   The laminate according to any one of claims 1 to 5, wherein a content of the isophthalic acid is 0.5 mol% or more and 5.0 mol% or less with respect to all dicarboxylic acid units constituting the polyethylene terephthalate.   The laminated body according to any one of claims 1 to 6, wherein the intrinsic viscosity of the polyethylene terephthalate is 0.58 dl / g or more and 0.80 dl / g or less.