JP7071705B2 - Laminate - Google Patents

Description

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

Plastics, which are fossil fuel-derived materials, are mainly used in the manufacture of packaging materials for filling products such as pharmaceuticals, cosmetics, and foods from the viewpoint of ease of molding and cost. Polyester-based resins, polyolefin-based resins, polyamide-based resins, and the like are used as plastic materials that are widely used as materials for packaging containers. Among them, polyester-based 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, etc., and are inexpensive.

Polyester is obtained by polycondensing a diol unit and a dicarboxylic acid unit. For example, polyethylene terephthalate (hereinafter, may be abbreviated as PET) is produced by using ethylene glycol and terephthalic acid as raw materials and subjecting them to an esterification reaction 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 industrially produced from xylene.

In recent years, with respect to such fossil fuel-derived materials, there has been an increasing movement year by year to reduce the use of fossil fuels for various purposes in consideration of the environment and to reduce CO ₂ emissions. As an attempt to reduce the use of such fossil fuels, a method has been proposed in which polyester resin recovered from used packaging materials such as PET bottles can be reused and recycled as recycled polyester for molding of packaging materials (). For example, see Patent Documents 1 and 2). In Patent Documents 1 and 2, CO ₂ emissions are reduced by using polyester as a part of the packaging material, which is made by recovering used products formed from fossil fuel-derived polyester so that they can be reused. It is proposed to try.

Japanese Unexamined Patent Publication No. 2011-256328 Japanese Unexamined Patent Publication No. 2012-41463

However, packaging materials using recycled PET recycled by mechanical recycling, in which recovered PET bottles and other polyester resin products are crushed, washed and reused, are contaminated due to foreign matter adhering to the recycled PET. There is an impression that nations may have occurred. For this reason, it is difficult to obtain the trust of consumers for packaging materials manufactured by using a laminated body made of recycled PET, particularly packaging materials for filling products such as foods.

An object of the present invention is to provide a laminate capable of effectively solving such a problem.

The present invention is a laminate including at least a base material layer (excluding the polyester film A below) , a barrier adhesive layer, and a sealant layer in this order, and the base material layer is the first. A layer, a second layer, and a third layer are provided in this order, the first layer and the third layer are composed of only virgin polyethylene terephthalate, and the second layer is composed of only recycled polyethylene terephthalate. The recycled polyethylene terephthalate contains polyethylene terephthalate having ethylene glycol as a diol unit and terephthalic acid and isophthalic acid as a dicarboxylic acid unit, and the barrier. The sex adhesive layer contains a polyester polyol having two or more hydroxyl groups in one molecule as a functional group and an isocyanate compound having two or more isocyanate groups in one molecule as a functional group, and is the barrier adhesive layer. It is a laminated body having a thickness of 0.5 μm or more and 6.0 μm or less.
Polyester film A:
A polyester film having at least two layers,
A first layer containing biomass polyester containing biomass-derived ethylene glycol as a diol unit and fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit.
A second containing recycled polyester obtained by recycling a polyester resin product containing a fossil fuel-derived diol and / or a biomass-derived ethylene glycol as a diol unit and a polyester containing a fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit. Layer and
Including polyester film

In the laminate according to the present invention, the polyester polyol may be a polycondensate of an ortho-oriented polyvalent carboxylic acid or an anhydride thereof and a polyhydric alcohol.

で表される化合物であり、
一般式（１）において、Ｒ_１、Ｒ_２、Ｒ_３は、各々独立に、Ｈ又は下記の一般式（２）

で表される化合物であり、
式（２）において、ｎは１～５の整数を表し、Ｘは、置換基を有してもよい１，２－フェニレン基、１，２－ナフチレン基、２，３－ナフチレン基、２，３－アントラキノンジイル基、及び２，３－アントラセンジイル基から成る群から選ばれるアリーレン基を表し、Ｙは炭素原子数２～６のアルキレン基を表し、但し、Ｒ _１ 、Ｒ _２ 、Ｒ _３ のうち少なくとも一つは、一般式（２）で表される基を表すものであってもよい。 In the laminate according to the present invention, the polyester polyol has the following general formula (1).

It is a compound represented by
In the general formula (1), R ₁ , R ₂ , and R ₃ are independently H or the following general formula (2).

It is a compound represented by
In the formula (2), n represents an integer of 1 to 5, and X is a 1,2-phenylene group, a 1,2-naphthylene group, a 2,3-naphthylene group, 2, which may have a substituent. Represents an arylene group selected from the group consisting of a 3-anthraquinonediyl group and a 2,3-anthracendyl group, where Y represents an alkylene group having 2 to 6 carbon atoms, except that R1 _, R2 _{, and} R3 . At least one of them may represent a group represented by the general formula (2) .

In the laminate according to the present invention, the polyester polyol may have an isocyanul ring.

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

In the laminate according to the present invention, the ultimate 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 to provide a laminated body having an excellent CO ₂ reduction effect and excellent hygiene as compared with a laminated body made of polyethylene terephthalate which is not recycled.

It is a schematic cross-sectional view which shows an example of the laminated body by this embodiment. It is a schematic cross-sectional view which shows an example of the base material layer.

<Laminated body>
The laminate according to the present embodiment includes at least a base material layer, a barrier adhesive layer, and a sealant layer in this order. The laminate may further include a printing layer, another layer, or the like.

The laminated body according to this embodiment will be described with reference to the drawings. FIG. 1 shows an example of a schematic cross-sectional view of the laminated body according to the present embodiment.

The laminate 10 shown in FIG. 1 includes a base material layer 11, a barrier adhesive layer 12, and a sealant layer 13 in this order. Although not shown, the laminate 10 may further include a print layer provided on the substrate layer 11. In the packaging bag provided with the laminate 10 shown in FIG. 1, the sealant layer 13 constitutes the inner surface of the packaging bag.

Hereinafter, each layer constituting the laminated body will be described.

[Base layer]
The base material layer contains polyethylene terephthalate recycled by mechanical recycling (hereinafter, polyethylene terephthalate is also referred to as PET). Specifically, the base material layer contains PET in which PET bottles are recycled by mechanical recycling, in which the diol unit is ethylene glycol and the dicarboxylic acid unit contains terephthalic acid and isophthalic acid. Here, mechanical recycling generally refers to crushing a recovered polyethylene terephthalate resin product such as a PET bottle, washing it with an alkali to remove stains and foreign substances on the surface of the PET resin product, and then drying it at a high temperature and under reduced pressure for a certain period of time. This is a method in which the contaminants remaining inside the PET resin are diffused and decontaminated, the stains on the resin product made of the PET resin are removed, and the resin is returned to the PET resin again. Hereinafter, in the present specification, polyethylene terephthalate obtained by recycling PET bottles is referred to as "recycled polyethylene terephthalate (hereinafter, also referred to as recycled PET)", and non-recycled polyethylene terephthalate is referred to as "virgin polyethylene terephthalate (hereinafter, also 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, preferably 1.0 mol%, based on all the dicarboxylic acid units constituting the PET. It is more preferably 2.5 mol% or more. If the content of isophthalic acid is less than 0.5 mol%, the flexibility may not be improved, while if it exceeds 5 mol%, the melting point of PET may be lowered and the heat resistance may be insufficient. The PET may be a biomass PET as well as a PET derived from ordinary fossil fuels. The "biomass PET" contains ethylene glycol derived from biomass as a diol unit and contains a dicarboxylic acid derived from fossil fuel as a dicarboxylic acid unit. This biomass PET may be formed only of PET having a biomass-derived ethylene glycol as a diol unit and a fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit, or a biomass-derived ethylene glycol and a fossil fuel-derived diol. It may be formed of PET having a diol unit and a dicarboxylic acid derived from fossil fuel as a dicarboxylic acid unit.

The PET used in the PET bottle can be obtained by a conventionally known method of polycondensing the above-mentioned diol unit and dicarboxylic acid unit. Specifically, a general method of melt polymerization such as performing an esterification reaction and / or an ester exchange reaction between the above diol unit and a dicarboxylic acid unit and then performing a polycondensation reaction under reduced pressure, or an organic solvent. It can be produced by a known solution heating dehydration condensation method or the like using the above.

The amount of the diol unit used in producing the PET 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 depolymerization. Since there is distillation during the reaction, it is used in excess of 0.1 mol% or more and 20 mol% or less.

Further, the polycondensation reaction is preferably carried out 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 it may be added at the time of charging the raw materials or at the start of reduced pressure.

PET bottles recycled from PET bottles are polymerized and solidified as described above, and then solid-phase polymerization is performed as necessary in order to further increase the degree of polymerization and remove oligomers such as cyclic trimers. You may go. Specifically, in the solid phase polymerization, the PET is chipped and dried, and then heated at a temperature of 100 ° C. or higher and 180 ° C. or lower for about 1 to 8 hours to pre-crystallize the PET, and then at 190 ° C. It is carried out by heating at a temperature of 230 ° C. or lower for 1 hour to several tens of hours under an inert gas atmosphere or under reduced pressure.

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

The base material layer preferably contains recycled PET in a proportion of 50% by weight or more and 95% by weight or less, and may contain virgin PET in addition to recycled PET. As the virgin PET, the diol unit as described above may be ethylene glycol, the dicarboxylic acid unit may be PET containing terephthalic acid and isophthalic acid, and the dicarboxylic acid unit may be PET containing no isophthalic acid. May be good. Further, the base material layer may contain polyester other than PET. For example, as the dicarboxylic acid unit, an aliphatic dicarboxylic acid or the like may be contained in addition to the aromatic dicarboxylic acid such as terephthalic acid and isophthalic acid.

Specific examples of the aliphatic dicarboxylic acid include chains having 2 or more and 40 or less carbon atoms, such as oxalic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, dodecanedioic acid, dimer acid and cyclohexanedicarboxylic acid. The shape or alicyclic dicarboxylic acid can be mentioned. Examples of the derivative of the aliphatic dicarboxylic acid include lower alkyl esters such as the methyl ester of the aliphatic dicarboxylic acid, ethyl ester, propyl ester and butyl ester, and cyclic acid anhydride of the aliphatic dicarboxylic acid such as succinic anhydride. .. Among these, as the aliphatic dicarboxylic acid, adipic acid, succinic acid, dimer acid or a mixture thereof is preferable, and succinic acid as a main component is particularly preferable. As the derivative of the aliphatic dicarboxylic acid, methyl esters of adipic acid and succinic acid, or mixtures thereof are more preferable.

The base material layer composed of such PET may be a single layer or a multilayer layer. As shown in FIG. 2, when the recycled PET as described above is used as the base material layer, the base material layer may be provided with three layers of the first layer 31, the second layer 32, and the third layer 33. In this case, in the laminated body, the third layer 33 of the base material layer is located on the sealant layer side. Further, in this case, the second layer 32 is a layer composed only of recycled PET or a mixed layer of recycled PET and virgin PET, and the first layer 31 and the third layer 33 are a layer composed only of virgin PET. It is preferable to do so. As described above, by using only virgin PET for the first layer 31 and the third layer 33, it is possible to prevent the recycled PET from being exposed from the front surface or the back surface of the base material layer. Therefore, the hygiene of the laminated body can be ensured. Further, the base material layer may be a base material layer including two layers of the second layer 32 and the third layer 33 without providing the first layer 31 shown in FIG. 2. Further, the base material layer may be a base material layer including two layers of the first layer 31 and the second layer 32 without providing the third layer 33 shown in FIG. Also in these cases, the second layer 32 is a layer composed only of recycled PET or a mixed layer of recycled PET and virgin PET, and the first layer 31 and the third layer 33 are layers composed only of virgin PET. Is preferable.

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

Various additives can be added to the PET constituting the base material layer in the manufacturing process thereof or after the manufacturing thereof as long as the characteristics are not impaired. Additives include, for example, plasticizers, UV stabilizers, color inhibitors, matting agents, deodorants, flame retardants, weathering agents, antistatic agents, thread friction reducing agents, mold release agents, antioxidants, ions. Examples include replacement agents and colored pigments. The additive is preferably added in the range of 5% by mass or more and 50% by mass or less, preferably 5% by mass or more and 20% by mass or less, based on the entire resin composition containing PET.

The base material layer can be formed by, for example, forming a film by the T-die method using the above-mentioned PET. Specifically, after the above-mentioned PET is dried, it is supplied to a melt extruder heated to a temperature equal to or higher than the melting point of PET (Tm) to Tm + 70 ° C. to melt the resin composition, for example, T-die. A film can be formed by extruding a sheet-like material from a die such as a die and quenching and solidifying the extruded sheet-like material 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 and 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 vertical direction to obtain a vertically 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 higher and 100 ° C. or lower. The magnification of 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 times, the thickness unevenness of the PET film becomes large and it is difficult to obtain a good film.

The vertically stretched film is subsequently subjected to each of the treatment steps of lateral stretching, heat fixing, and heat relaxation to obtain a biaxially stretched film. The transverse stretching is usually performed in a temperature range of 50 ° C. or higher and 100 ° C. or lower. The ratio of lateral stretching depends on the required characteristics of this application, but is preferably 2.5 times or more and 5.0 times or less. 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 is likely to occur during film formation.

After the transverse stretching, a heat fixing treatment is subsequently performed, and a preferable heat fixing temperature range is Tg + 70 to Tm-10 ° C. of PET. Further, the heat fixing time is preferably 1 second or more and 60 seconds or less. Further, for applications that require a reduction in the heat shrinkage rate, heat relaxation treatment may be performed as necessary.

The thickness of the PET film obtained as described above is arbitrary depending on the intended use, but is usually 5 μm or more and 100 μm or less, preferably 5 μm or more and 25 μm or less. The breaking strength of the PET film is 5 kg / mm ² or more and 40 kg / mm ^{2 or less in the MD direction, 5 kg / mm 2 or more and 35 kg / mm 2 or less} in the TD direction, and the breaking elongation is 50 in the MD direction. % Or more and 350% or less, and 50% or more and 300% or less in the TD direction. 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, the "fossil fuel PET" is a fossil fuel-derived diol as a diol unit and a fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit. Further, the recycled PET may be obtained by recycling a PET resin product formed by using fossil fuel PET, or may be obtained by recycling a PET resin product formed by using biomass PET. There may be.

[Barrier adhesive layer]
The barrier adhesive layer is a layer provided for adhering the base material layer 11 and the sealant layer 13, and has a function of imparting a barrier property to the laminated body. By providing the barrier adhesive layer, even if foreign matter adheres to the recycled PET used for the base material layer, it is a layer for suppressing the defect that the foreign matter appears on the sealant layer side rather than the barrier layer. be. As a result, in the packaging bag constructed by using the laminated body, it is possible to suppress the problem that foreign matter appears on the inner surface side of the barrier layer, so that the hygiene of the contents can be ensured.

The barrier adhesive layer is formed by applying an adhesive composition as described below to the surface of the film on the side to be laminated among the film containing the base material layer 11 and the film containing the sealant layer 13 and drying the film. It is a layer to be. As a coating method of the above-mentioned laminating adhesive, for example, a direct gravure roll coating method, a gravure roll coating method, a kiss coating method, a reverse roll coating method, a fonten method, a transfer roll coating method, or other methods can be applied. ..

The barrier adhesive layer has a gas barrier property, particularly an oxygen and water vapor barrier property. The thickness of the barrier adhesive layer is, for example, 0.5 μm or more and 6.0 μm or less, preferably 0.8 μm or more and 5.0 μm or less, and more preferably 1.0 μm or more and 4.5 μm or less. If it is thinner than the above range, the gas barrier property tends to be insufficient, and if it is thicker than the above range, the bending resistance tends to be inferior, which tends to lead to a decrease in the gas barrier property after bending.

The barrier adhesive layer comprises a cured product of an adhesive composition containing a polyester polyol, an isocyanate compound, and a plate-like inorganic compound. The polyester polyol has two or more hydroxyl groups in one molecule as a functional group. Further, the isocyanate compound has two or more isocyanate groups in one molecule as a functional group. The polyester polyol has, for example, a polyester structure and a polyester polyurethane structure as the main skeleton.

The adhesive composition may further contain a phosphate-modified compound, a coupling agent, cyclodextrin and / or a derivative thereof, and the like.

The glass transition temperature of the cured coating film of the adhesive composition is preferably in the range of −30 ° C. or higher and 80 ° C. or lower. More preferably, it is 0 ° C. or higher and 70 ° C. or lower. More preferably, it is 25 ° C. or higher and 70 ° C. or lower. When the glass transition temperature is higher than 80 ° C., the flexibility of the cured coating film near room temperature is lowered, so that the adhesion to the film is deteriorated and the adhesive strength may be lowered. On the other hand, when the temperature is lower than -30 ° C, there is a risk that sufficient oxygen barrier properties will not be obtained due to the vigorous molecular motion of the cured coating film near room temperature, and there is a risk that the adhesive strength will decrease due to insufficient cohesive force.

As a specific example of the adhesive composition containing a polyester polyol, an isocyanate compound, and a plate-like inorganic compound, a series of oxygen barrier adhesive PASLIM sold by DIC Corporation can be used, and in particular, PASLIM and the like are preferably used.

(Polyester polyol)
As the polyester polyol having two or more hydroxyl groups in one molecule as a functional group, for example, the following [1st example] to [1st example] can be used.
[1st example] Polyester polyol obtained by polycondensing an ortho-oriented polyvalent carboxylic acid or its anhydride and a polyhydric alcohol [2nd example] Polyester polyol having a glycerol skeleton [3rd example] Having an isocyanul ring Polyester polyols Each polyester polyol will be described below.

[1st Example] Ortho-Orientation Polyvalent carboxylic acid or its anhydride and a polyhydric alcohol are polycondensed to obtain a polyester polyol. The polyester polyol according to the first example contains at least one orthophthalic acid and its anhydride. Polycondensation obtained by polycondensing the polyvalent carboxylic acid component contained and the polyhydric alcohol component containing at least one selected from the group consisting of ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexanedimethanol. It may be a body. In particular, a polyester polyol having a content of the orthophthalic acid and its anhydride in an amount of 70 to 100% by mass with respect to all the components of the polyvalent carboxylic acid is preferable.

The polyester polyol according to the first example requires the orthophthalic acid and its anhydride as the polyvalent carboxylic acid component, but copolymerizes other polyvalent carboxylic acid components as long as the effects of the present embodiment are not impaired. You may let me. Specifically, the aliphatic polyvalent carboxylic acid includes succinic acid, adipic acid, azelaic acid, sebacic acid, dodecandicarboxylic acid and the like, and the unsaturated bond-containing polyvalent carboxylic acid includes maleic anhydride and maleic acid. Fumaric acid and the like, 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid as the alicyclic polyvalent carboxylic acid, and terephthalic acid, isophthalic acid and pyromerit as the aromatic polyvalent carboxylic acid. Acid, trimellitic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid, 1,2-bis (phenoxy) ethane-p, p '-Dicarboxylic acids and anhydrides or ester-forming derivatives of these dicarboxylic acids; polybasic acids such as p-hydroxybenzoic acid, p- (2-hydroxyethoxy) benzoic acid and ester-forming derivatives of these dihydroxycarboxylic acids. It can be used alone or in a mixture of two or more. Of these, succinic acid, 1,3-cyclopentanedicarboxylic acid, and isophthalic acid are preferable.

Examples of the polyhydric alcohol component and other components include those mentioned above.

一般式（１）において、Ｒ_１、Ｒ_２、Ｒ_３は、各々独立に、Ｈ又は下記の一般式（２）で表される化合物である。

[2nd Example] Polyester polyol having a glycerol skeleton As the polyester polyol according to the 2nd example, a polyester polyol having a glycerol skeleton represented by the general formula (1) can be mentioned.

In the general formula (1), R ₁ , R ₂ , and R ₃ are each independently H or a compound represented by the following general formula (2).

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

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

Further, any one of R ₁ , R ₂ , and R ₃ is a compound represented by the general formula (2), and any two of R ₁ , R ₂ , and R ₃ are the general formula (2). A mixture of two or more of the compound represented by the above group and the compound represented by the general formula (2) in which all of R ₁ , R ₂ , and R ₃ are represented by the above general formula (2). May be good.

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

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

The polyester resin compound having a glycerol skeleton represented by the general formula (1) requires glycerol, an aromatic polyvalent carboxylic acid in which the carboxylic acid is substituted at the ortho position or an anhydride thereof, and a polyhydric alcohol component. Obtained by reacting as an ingredient.

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

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

一般式（３）において、Ｒ_１、Ｒ_２、Ｒ_３は、各々独立に、「－（ＣＨ_２）ｎ１－ＯＨ（但しｎ１は２～４の整数を表す）」、又は、一般式（４）の構造を表す。

[3rd Example] Polyester polyol having an isocyanul ring The polyester polyol according to the 3rd example is a polyester polyol having an isocyanul ring represented by the following general formula (3).

In the general formula (3), R ₁ , R ₂ , and R ₃ are independently "-(CH ₂ ) n1-OH (where n1 represents an integer of 2 to 4)" or the general formula (4). ) Represents the structure.

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

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

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

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

The substituent of X is preferably a hydroxyl group, a cyano group, a nitro group, an amino group, a phthalimide group, a carbamoyl group, an N-ethylcarbamoyl group or a phenyl group, preferably a hydroxyl group, a phenoxy group, a cyano group, a nitro group or a phthalimide group. , Phenyl groups are most preferred.

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

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

Further, any one of R ₁ , R ₂ , and R ₃ is a compound represented by the general formula (4), and any two of R ₁ , R ₂ , and R ₃ are the general formula (4). A mixture of two or more of the compound represented by the above group and the compound represented by the general formula (4) in which all of R ₁ , R ₂ , and R ₃ are represented by the above general formula (4). May be good.

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

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

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

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

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

Among them, 1,3,5-tris (2-hydroxyethyl) isocyanuric acid or 1,3,5-tris (2-hydroxypropyl) isocyanuric acid is used as the triol compound having an isocyanul ring, and the carboxylic acid is in the ortho position. A polyester polyol compound having an isocyanul ring using orthophthalic acid anhydride as the aromatic polyvalent carboxylic acid or its anhydride substituted with and using ethylene glycol as the polyhydric alcohol is particularly excellent in oxygen barrier property and adhesiveness. preferable.

The isocyanul ring is highly polar and trifunctional. Therefore, the entire system can be made highly polar, and the crosslink density can be increased. From this point of view, it is preferable that the isocyanul ring is contained in an amount of 5% by mass or more based on the total solid content of the adhesive resin.

The reason why the adhesive having an isocyanul ring can ensure the oxygen barrier property and the dry laminate adhesive property is presumed as follows.

The isocyanul ring is highly polar and does not form hydrogen bonds. Generally, as a method for improving adhesiveness, a method of blending highly polar functional groups such as hydroxyl groups, urethane bonds, ureido bonds, and amide bonds is known, and resins having these bonds form intermolecular hydrogen bonds. It is easy to impair the solubility in ethyl acetate and 2-butanone solvents often used for dry laminate adhesives, but the polyester resin having an isocyanul ring does not impair the solubility, so it can be easily diluted. Is.

Further, since the isocyanul ring is trifunctional, a polyester polyol compound having the isocyanul ring as the center of the resin skeleton and a polyester skeleton having a specific structure in the branched chain can obtain a high crosslink density. It is presumed that by increasing the crosslink density, the gap through which a gas such as oxygen passes can be reduced. As described above, it is presumed that the isocyanul ring has high polarity without forming an intermolecular hydrogen bond and a high crosslink density can be obtained, so that oxygen barrier property and dry laminate adhesiveness can be ensured.

(Isocyanate compound)
The isocyanate compound has two or more isocyanate groups in the molecule and may be either aromatic or aliphatic, may be either a low molecular weight compound or a high molecular weight compound, and may be a diisocyanate compound having two or three isocyanate groups. Known compounds such as the above polyisocyanate compounds can be used. The isocyanate compound may be a blocked isocyanate compound obtained by an addition reaction using a known isocyanate blocking agent by a known and commonly used appropriate method.

Among them, polyisocyanate compounds are preferred from the viewpoint of adhesiveness and retort resistance, and those having an aromatic ring are preferable from the viewpoint of imparting oxygen barrier properties, and in particular, isocyanate compounds containing a metaxylene skeleton are urethane-based. It is preferable because the oxygen barrier property can be improved not only by hydrogen bonding but also by π-π stacking between aromatic rings.

Specific examples of the isocyanate compound include tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydride diphenylmethane diisocyanate, metaxylylene diisocyanate, hydride xylylene diisocyanate, isophorone diisocyanate, and isocyanate compounds thereof. Trimers and excess amounts of these isocyanate compounds, such as ethylene glycol, propylene glycol, metaxylylene alcohol, 1,3-bishydroxyethylbenzene, 1,4-bishydroxyethylbenzene, trimethylolpropane, glycerol, pentaerythritol. , Erythritol, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, metaxylylene diamine and other low molecular weight active hydrogen compounds and their alkylene oxide adducts, various polyester resins, polyether polyols, polyamides polymers. Examples thereof include an adduct-form, a bullet-form, and an allophanate-form obtained by reacting with an active hydrogen compound and the like.

(Plate-shaped inorganic compound)
The plate-like inorganic compound has a characteristic that the laminating strength and the barrier property of the barrier adhesive layer are particularly improved due to the plate-like shape.
Specific examples of the plate-like inorganic compound include hydrous silicate (phyllosilicate mineral, etc.), kaolinite-serpentine clay mineral (halosite, kaolinite, enderite, dikite, nacrite, etc.), antigolite, and chrysotile. Etc.), Pyrophyllite-Tark (pyrophyllite, talc, kerolai, etc.), Smectite clay minerals (montmorillonite, biderite, nontronite, saponite, hectrite, soconite, stibnsite, etc.), vermiculite clay minerals (vermiculite, etc.) Etc.), mica or mica clay minerals (white mica, mica such as gold mica, margarite, tetracyrylic mica, teniolite, etc.), green mudstones (cookate, sudowite, clinochloa, chamosite, nimite, etc.), hydrotal Examples thereof include sites, plate-shaped barium sulfate, boehmite, aluminum polyphosphate, and the like, and one or more of these can be used.

The average particle size of the plate-shaped inorganic compound is not particularly limited, but is preferably 0.1 μm or more, and more preferably 1 μm or more. When the average particle size is 0.1 μm or less, the length of the long side is short, which causes a problem that it is difficult to improve the oxygen barrier ability and a problem that it is difficult to improve the adhesive strength because the detour path of oxygen molecules is not long. .. The side with a large average particle size is not particularly limited. When a large plate-like inorganic compound is contained in the coating method of the adhesive composition and defects such as streaks occur on the coated surface, it is preferable to use a material having an average particle size of 100 μm or less, more preferably 20 μm or less.

The aspect ratio of the plate-like inorganic compound is preferably high in order to improve the barrier ability due to the maze effect of oxygen. Specifically, it is preferably 3 or more, more preferably 10 or more, and most preferably 40 or more.

The content of the plate-like inorganic compound is not particularly limited, but is preferably 5% by mass or more and 50% by mass or less in the barrier adhesive layer. If it is less than 5% by mass, the barrier property is difficult to improve, and if it exceeds 50% by mass, the adhesiveness of the coated surface of the adhesive composition is lowered and it becomes difficult to laminate, or the adhesive strength may be insufficient. Is.

In addition to the above-mentioned components, the adhesive composition for forming the barrier adhesive layer may further contain a phosphoric acid-modified compound, a coupling agent, cyclodextrin and the like.

(Phosphoric acid denatured compound)
The phosphoric acid-modified compound is, for example, a compound represented by the following general formula (5) or (6).

一般式（５）において、Ｒ_１、Ｒ_２、Ｒ_３は、水素原子、炭素数１～３０のアルキル基、（メタ）アクリロイル基、置換基を有してもよいフェニル基、（メタ）アクリロイルオキシ基を有する炭素数１～４のアルキル基から選ばれる基であるが、少なくとも一つは水素原子であり、ｎは、１～４の整数を表す。

In the general formula (5), R ₁ , R ₂ , and R ₃ are a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, a (meth) acryloyl group, a phenyl group which may have a substituent, and (meth) acryloyl. It is a group selected from an alkyl group having 1 to 4 carbon atoms having an oxy group, at least one of which is a hydrogen atom, and n represents an integer of 1 to 4 carbon atoms.

式中、Ｒ_４、Ｒ_５は、水素原子、炭素数１～３０のアルキル基、（メタ）アクリロイル基、置換基を有してもよいフェニル基、（メタ）アクリロイルオキシ基を有する炭素数１～４のアルキル基から選ばれる基であり、ｎは１～４の整数、ｘは０～３０の整数、ｙは０～３０の整数を表すが、ｘとｙが共に０である場合を除く。

In the formula, R ₄ and R ₅ have a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, a (meth) acryloyl group, a phenyl group which may have a substituent, and 1 carbon number having a (meth) acryloyloxy group. It is a group selected from the alkyl groups of ~ 4, where n is an integer of 1 to 4, x is an integer of 0 to 30, y is an integer of 0 to 30, except when x and y are both 0. ..

The phosphoric acid-modified compound has an effect of improving the laminating strength with respect to the inorganic member of the present embodiment, and a known and commonly used compound can be used.

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

The content of the phosphoric acid-modified compound is preferably 0.005% by mass or more and 10% by mass or less in the adhesive resin composition of the present embodiment. More preferably, it is 0.01% by mass or more and 1% by mass or less. If it is less than 0.005% by mass, good adhesion cannot be obtained. If it is more than 10% by mass, the barrier property may be deteriorated.

(Coupling agent)
The coupling agent is a silane-based coupling agent, a titanium-based coupling agent, or an aluminum-based coupling agent represented by the following general formula (7). These coupling agents may be used alone or in combination of two or more.

Examples of the silane coupling agent include vinyl trichlorosilane, vinyl trimethoxysilane, vinyl triethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and γ-glycidoxypropyltrimethoxysilane. γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxytrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacry Propylpropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β ( Aminoethyl) γ-Aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercapto Examples thereof include propyltrimethoxysilane, 3-isocyanuppropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) and the like.

Examples of the titanium-based coupling agent include isopropyltriisostearoyl titanate, isopropyltri (N-aminoethyl-aminoethyl) titanate, isopropyltridodecylbenzenesulfonyl titanate, isopropyltris (dioctylpyrophosphate) titanate, and tetraoctyl. Bis (didodecylphosphite) titanate, tetraoctylbis (ditridecylphosphite) titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltrioctainoltitanate, isopropyldimethacrylic isostearoyl Examples thereof include titanate, isopropylisostearoyl diacrylic titanate, diisostearoyl ethylene titanate, isopropyltri (dioctyl phosphate) titanate, isopropyltricylphenyl titanate, dicumylphenyloxyacetate titanate and the like.

Specific examples of the aluminum-based coupling agent include acetalkoxyaluminum diisopropyrate, diisopropoxyaluminum ethylacetate, diisopropoxyaluminum monomethacrylate, andisopropoxyaluminum alkylacetate monomethate (dioctyl phosphate). Examples thereof include aluminum-2-ethylhexanoate oxide trimmer, aluminum stearate oxide trimmer, and alkylacetoacetate aluminum oxide trimmer.

(Cyclodextrin and / or its derivative)
The cyclodextrin and / or its derivative is a preferable component for obtaining 1) excellent adhesion to a film having an inorganic layer, and 2) excellent enhancement of an oxygen barrier. Specifically, for example, in addition to cyclodextrin, cyclodextrins such as alkylated cyclodextrin, acetylated cyclodextrin, and hydroxyalkylated cyclodextrin in which the hydrogen atom of the hydroxyl group of the glucose unit is replaced with another functional group are used. be able to. Also, branched cyclic dextrins can be used. The cyclodextrin skeleton in cyclodextrin and cyclodextrin derivatives includes α-cyclodextrin consisting of 6 glucose units, β-cyclodextrin consisting of 7 glucose units, and γ-cyclodextrin consisting of 8 glucose units. Any of these can be used. These compounds may be used alone or in combination of two or more. In addition, these cyclodextrins and / or their derivatives may be collectively referred to as dextrin compounds hereafter.

From the viewpoint of compatibility and dispersibility in the adhesive composition, it is preferable to use a cyclodextrin derivative as the cyclodextrin compound. From the viewpoint of the polarity of the various resins, the degree of substitution is preferably in the range of 0.1 or more and 14 or less / glucose, and more preferably in the range of 0.3 or more and 8 or less / glucose. ..

As the alkylated cyclodextrin, for example, methyl-α-cyclodextrin, methyl-β-cyclodextrin, methyl-γ-cyclodextrin and the like can be used. These compounds may be used alone or in combination of two or more.

As the acetylated cyclodextrin, for example, monoacetyl-α-cyclodextrin, monoacetyl-β-cyclodextrin, monoacetyl-γ-cyclodextrin and the like can be used. These compounds may be used alone or in combination of two or more.

As the hydroxyalkylated cyclodextrin, for example, hydroxypropyl-α-cyclodextrin, hydroxypropyl-β-cyclodextrin, hydroxypropyl-γ-cyclodextrin and the like can be used. These compounds may be used alone or in combination of two or more.

The content of the cyclodextrin and / or its derivative is not particularly limited, but 0. The range is preferably 01 parts by mass or more and 20 parts by mass or less, more preferably 0.05 parts by mass or more and 10 parts by mass or less, and further preferably 0.1 parts by mass or more and 5 parts by mass or less.

When the adhesive composition comprises cyclodextrin and / or a derivative thereof, the cyclic and regularly arranged hydroxyl groups and ether groups of cyclodextrin and / or a derivative thereof coordinate a plurality of interaction points with the inorganic surface. By having it as a bond or a hydrogen bond, it is assumed that it can be an adhesive having strong adhesive strength when laminating various films having an inorganic layer, especially metal foil, metal vapor deposition film, and transparent vapor deposition film. There is. It is also assumed that a large number of hydroxyl groups of cyclodextrin and / or its derivatives interact with each other to narrow the free volume pores through which the gas permeates, thereby improving the barrier function.

(solvent)
If the polyester polyol and the isocyanate compound can be dissolved, the phosphoric acid-modified compound, the plate-like inorganic compound, etc. can be uniformly dispersed, and the compound has an appropriate boiling point and volatility from the viewpoint of the process of forming the barrier adhesive layer. There are no particular restrictions.

[Sealant layer]
The sealant layer is on the innermost layer side when it is used as a package. 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 resin material derived from fossil fuel or may contain a resin material derived from biomass.

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, and specifically, for example, low-density polyethylene (LDPE), medium-density polyethylene (MDPE), and high density polyethylene (MDPE). Density polyethylene (HDPE), linear (linear) low density polyethylene (LLDPE), ethylene-α / olefin copolymer polymerized using a metallocene catalyst, random or block copolymer of ethylene / polypropylene, polypropylene, Ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methacrylate copolymer (EMAA), ethylene-methyl methacrylate Polypolymers (EMMA), ionomer resins, heat sealable ethylene / vinyl alcohol resins, or polyolefins such as methylpentene resins, ethylene-propylene copolymers, methylpentene polymers, polybutene polymers, polyethylene, polypropylene or cyclic olefin copolymers. Acid-modified polyolefin resin, polyvinyl acetate resin, poly (meth) acrylic obtained by modifying based resin and polyolefin resin with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and itaconic acid. Examples thereof include based resins, polyvinyl chloride-based resins, and other resins. 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, a coating film thereof, or the like.

When polyethylene is used as the resin material for forming the sealant layer, polyethylene derived from biomass may be polymerized in addition to ethylene obtained from fossil fuel as the raw material. As the biomass-derived ethylene, specifically, for example, those described in JP2012-251006 can be used. By using polyethylene obtained by polymerizing biomass-derived ethylene as a material constituting the sealant layer, it can be formed into a layer made of a carbon-neutral material. It is possible to reduce the amount of use of ethylene and reduce the environmental load.

As the polyethylene derived from biomass, commercially available polyethylene may be used. For example, a linear sugarcane-derived polyethylene of "C4LL-SLL118 (d = 0.916, MFR = 1.0 g / 10 minutes)" manufactured by Braskem Co., Ltd. may be used. 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 minutes)" can be used.

In this embodiment, the sealant layer is a single layer, but two or more sealant layers may be provided. When having two or more sealant layers, each may have the same composition or different compositions. For example, the sealant layer is composed of three layers in which the first layer, the second layer, and the third layer are laminated in order, and the first layer and the third layer are made of a fossil fuel-derived resin material, and the second layer is used. The layer may be a resin material containing a biomass-derived resin material. When the sealant layer is composed of two or more layers, it can be laminated by using the co-extrusion 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.

[Print layer]
The printing layer is used for decoration, display of contents, display of expiration date, display of manufacturers, sellers, etc., and for the purpose of giving a sense of beauty, such as letters, numbers, patterns, figures, symbols, and patterns. A layer that forms any desired print pattern. The printed layer can be provided as needed, and can be provided, for example, between the base material layer and the barrier layer, or between the barrier layer and the sealant layer. The printing layer may be provided on the entire surface of the base material layer, or may be provided on a part of the base material layer. The printed layer can be formed by using a conventionally known pigment or dye, and the forming method thereof is not particularly limited.

The printed layer preferably has a thickness of 0.1 μm or more and 10 μm or less, more preferably 1 μm or more and 5 μm or less, and further preferably 1 μm or more and 3 μm or less.

As described above, the base material layer contains recycled PET in a proportion of, for example, 50% by weight or more and 95% by weight or less. According to the present embodiment, since the base material layer contains recycled PET, it is possible to provide a laminated body having a higher CO ₂ reduction effect than a laminated body not containing recycled PET. Further, according to the present embodiment, the laminated body includes the above-mentioned barrier layer, so that the laminated body having excellent hygiene can be provided.

<Manufacturing method of laminated body>
The method for producing the laminate according to the present embodiment is not particularly limited, and the laminate can be produced by using a conventionally known method such as a dry laminate method.

The laminate according to the present embodiment has a chemical function, an electrical function, a magnetic function, a mechanical function, a friction / wear / lubrication function, an optical function, a thermal function, a surface function such as biocompatibility, and the like. It is also possible to perform secondary processing for the purpose of imparting. Examples of secondary processing include embossing, painting, bonding, printing, metallizing (plating, etc.), machining, surface treatment (antistatic treatment, corona discharge treatment, plasma treatment, photochromism treatment, physical vapor deposition, chemical vapor deposition, etc.) Coating, etc.) and the like. Further, the laminated body according to the present embodiment may be subjected to laminating processing (dry laminating or extruded laminating), bag making processing, and other post-treatment processing to produce a molded product.

The laminate can be used, for example, in a packaging bag for filling a product such as food. For example, the above laminated body is used and folded in half, or two laminated bodies are prepared and the surfaces of the sealant are overlapped with each other facing each other, and the peripheral end thereof is, for example, a side seal type. , Two-way sticker type, three-way sticker type, four-way sticker type, envelope sticker sticker type, gassho sticker sticker type (pillow sticker type), fold sticker type, flat bottom sticker type, square bottom sticker type, gusset type, etc. Can be heat-sealed to produce various forms of packaging bags.

In the above, as the 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 particularly suitably used as a packaging bag for sealing and packaging foods and the like.

10 Laminated body 11 Base material layer 12 Barrier adhesive layer 13 Sealant layer

Claims (6)

A laminate including at least a base material layer (excluding the polyester film A below) , a barrier adhesive layer, and a sealant layer in this order.
The base material layer includes a first layer, a second layer, and a third layer in this order.
The first layer and the third layer are layers composed only of virgin polyethylene terephthalate, and are composed of only virgin polyethylene terephthalate.
The second layer is a layer composed only of recycled polyethylene terephthalate or a mixed layer of recycled polyethylene terephthalate and virgin polyethylene terephthalate.
The recycled polyethylene terephthalate contains polyethylene terephthalate having ethylene glycol as a diol unit and terephthalic acid and isophthalic acid as a dicarboxylic acid unit.
The barrier adhesive layer contains a polyester polyol having two or more hydroxyl groups in one molecule as a functional group and an isocyanate compound having two or more isocyanate groups in one molecule as a functional group.
The thickness of the barrier adhesive layer is 0.5 μm or more and 6.0 μm or less, which is a laminated body.
Polyester film A:
A polyester film having at least two layers,
A first layer containing biomass polyester containing biomass-derived ethylene glycol as a diol unit and fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit.
A second containing recycled polyester obtained by recycling a polyester resin product containing a fossil fuel-derived diol and / or a biomass-derived ethylene glycol as a diol unit and a polyester containing a fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit. Layer and
Including polyester film The laminate according to claim 1, wherein the polyester polyol is a polycondensate of an ortho-oriented polyvalent carboxylic acid or an anhydride thereof and a polyhydric alcohol. The polyester polyol has the following general formula (1).

It is a compound represented by
In the general formula (1), R ₁ , R ₂ , and R ₃ are independently H or the following general formula (2).

It is a compound represented by
In the formula (2), n represents an integer of 1 to 5, and X is a 1,2-phenylene group, a 1,2-naphthylene group, a 2,3-naphthylene group, 2, which may have a substituent. Represents an arylene group selected from the group consisting of a 3-anthraquinonediyl group and a 2,3-anthracendyl group, where Y represents an alkylene group having 2 to 6 carbon atoms, except that _R1 , _{R2 ,} and R3. The laminate according to claim 1, wherein at least one of them represents a group represented by the general formula (2). The laminate according to claim 1, wherein the polyester polyol has an isocyanul ring. The invention according to any one of claims 1 to 4, wherein the content of the isophthalic acid is 0.5 mol% or more and 5.0 mol% or less with respect to all the dicarboxylic acid units constituting the polyethylene terephthalate. Laminated body. The laminate according to any one of claims 1 to 5, wherein the polyethylene terephthalate has an ultimate viscosity of 0.58 dl / g or more and 0.80 dl / g or less.

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