JP2018171793A - Laminate for boil sterilization and packaging bag for boil sterilization having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate for boil sterilization that can be used in producing a packaging bag for boil sterilization excellent in boil sterilization resistance and hand tearability, while improving a biomass degree.SOLUTION: A laminate for boil sterilization 10 includes at least a first substrate layer 11, a second substrate layer 12 and a sealant layer 13 in this order. The first substrate layer 11 includes a polyethylene terephthalate. The second substrate layer 12 includes a polyamide. The sealant layer 13 includes a linear low-density polyethylene derived from a biomass and a low-density polyethylene. A content of the low-density polyethylene in the sealant layer 13 is 5-25 mass%. The sealant layer 13 includes a linear low-density polyethylene derived from a fossil fuel. The linear low-density polyethylene derived from biomass and/or derived from a fossil fuel is 75-95 wt.% in total. The laminate for boil sterilization is capable of producing a packaging bag excellent in boil sterilization resistance.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laminate for boil sterilization including at least a first base material layer, a second base material layer, and a sealant layer in this order. Furthermore, it is related with the packaging bag for boil sterilization provided with this laminated body.

  In recent years, with the growing demand for the establishment of a recycling-oriented society, the use of biomass has been attracting attention in the materials field, as it is desired to move away from fossil fuels as well as energy. Biomass is an organic compound photo-synthesized from carbon dioxide and water, and by using it, it is so-called carbon neutral renewable energy that becomes carbon dioxide and water again. In recent years, biomass plastics using these biomasses as raw materials have been rapidly put into practical use, and attempts have been made to produce various resins from biomass raw materials.

  As a biomass-derived resin, commercial production of polylactic acid (PLA) produced via lactic acid fermentation has begun, but it is biodegradable, and its performance as a plastic is now a general-purpose plastic. Therefore, it has not been widely used due to its limitations in product applications and product manufacturing methods. Moreover, life cycle assessment (LCA) evaluation is performed for PLA, and discussion is made on energy consumption at the time of PLA production, equivalence at the time of replacement of general-purpose plastics, and the like.

  Here, various types such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, and polyester are used as the general-purpose plastic. In particular, polyethylene is molded into films, sheets, bottles, etc., and is used for various applications such as packaging materials, and is used in large amounts all over the world. Therefore, using a conventional fossil fuel-derived polyethylene has a large environmental impact. Therefore, it is desired to reduce the amount of fossil fuel used by using raw materials derived from biomass for the production of polyethylene. For example, a resin film for packaging products using biomass-derived polyethylene has been proposed so far (see Patent Document 1).

JP 2012-251006 A

  The present inventors, together with polyolefins produced using ethylene obtained from conventional fossil fuels (hereinafter sometimes simply referred to as “polyolefins derived from fossil fuels”), biomass polyolefins using biomass-derived ethylene as a raw material By using (hereinafter, sometimes simply referred to as “biomass polyolefin”), a packaging bag having an increased biomass degree was developed while suppressing costs. In the process, the present inventors mixed boiled linear low density polyethylene and fossil fuel derived linear low density polyethylene to form a sealant layer for packaging bags. We faced the technical challenge of not being able to achieve both resistance and hand cutting. Thus, as a result of further studies, the present inventors have found a layer structure of a laminate capable of producing a packaging bag excellent in boil sterilization resistance and hand cutting properties, and have completed the present invention.

  Therefore, the objective of this invention is providing the laminated body which can manufacture the packaging bag for boil sterilization excellent in boil sterilization tolerance and hand cutting property, raising the degree of biomass.

According to a first aspect of the invention,
At least a laminate for boil sterilization comprising a first base material layer, a second base material layer, and a sealant layer in this order,
The first base layer includes polyethylene terephthalate,
The second substrate layer comprises polyamide;
The sealant layer includes biomass-derived linear low density polyethylene and low density polyethylene,
A laminate is provided in which the content of low-density polyethylene in the sealant layer is 5% by mass or more and 25% by mass or less.

  In the first aspect of the present invention, it is preferable that the sealant layer further includes a linear low density polyethylene derived from fossil fuel.

  In the 1st aspect of this invention, it is preferable that the said sealant layer contains 75 to 95 mass% in total of the linear low density polyethylene derived from the said biomass and / or a fossil fuel.

  In the 1st aspect of this invention, it is preferable that the biomass degree of the said sealant layer is 5% or more and 30% or less.

  In the first aspect of the present invention, it is preferable that the laminate further includes a transparent vapor deposition layer between the first base material layer and the second base material layer.

  In the first aspect of the present invention, the transparent vapor deposition layer is preferably an aluminum oxide vapor deposition layer.

  In the first aspect of the present invention, it is preferable that the laminate further includes a gas barrier coating film between the transparent vapor-deposited layer and the second base material layer.

  In the first aspect of the present invention, it is preferable that the laminate further includes a printing layer between the first base material layer and the second base material layer.

  In the first aspect of the present invention, the laminate has an adhesive layer between the first base material layer and the second base material layer and / or between the second base material layer and the sealant layer. It is preferable to further provide.

  In the 2nd aspect of this invention, the packaging bag for boil sterilization provided with the said laminated body is provided.

  The laminate according to the present invention comprises at least a first substrate layer containing polyethylene terephthalate, a second substrate layer containing polyamide, and a sealant layer in this order, and the sealant layer is a linear low density derived from biomass. The content of the low density polyethylene in the sealant layer is 5% by mass or more and 25% by mass or less, including polyethylene and low density polyethylene. Excellent boil sterilization packaging bags can be produced.

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 model front view which shows an example of the refilling pouch by this invention.

<Laminated body for boil sterilization>
The laminate according to the present invention comprises at least a first base material layer, a second base material layer, and a sealant layer in this order, and can be suitably used for boil sterilization. The laminate may further include a transparent vapor deposition layer, a gas barrier coating film, a printed layer, an adhesive layer, other layers, and the like. When the laminate includes two or more 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.
The laminated body 10 shown in FIG. 1 is provided with the 1st base material layer 11, the 2nd base material layer 12, and the sealant layer 13 in this order. As for the packaging bag provided with the laminated body 10, the sealant layer 13 is located in the inner surface side.
The laminate 20 shown in FIG. 2 includes a first base material layer 21, a transparent vapor deposition layer 24, a gas barrier coating film 25, a print layer 26, an adhesive layer 27, a second base material layer 22, and an adhesive. The layer 28 and the sealant layer 23 are provided in this order. As for the packaging bag provided with the laminated body 20, the sealant layer 23 is located in the inner surface side.
Hereinafter, each layer which comprises a laminated body is demonstrated.

[Base material layer]
The laminated body by this invention is equipped with a 1st base material layer and the 2nd base material layer located inside a laminated body at least. By providing at least two base material layers, hand cutting properties and strength can be improved when a packaging bag is manufactured.

  The first base material layer is a resin layer containing polyethylene terephthalate. The first base material layer is preferably stretched and biaxially stretched. Since water resistance improves by providing a polyethylene terephthalate resin layer as a 1st base material layer, the boil sterilization tolerance of the packaging bag for boil sterilization can be improved. Moreover, hand tearability can be improved by providing a polyethylene terephthalate resin layer as a 1st base material layer.

  The polyethylene terephthalate used for the first substrate layer may be derived from biomass or derived from fossil fuel. The first base layer may include both biomass-derived polyethylene terephthalate and fossil fuel-derived polyethylene terephthalate. The biomass degree of the whole laminated body can be improved by using biomass-derived polyethylene terephthalate as at least a part of the first base material layer. Biomass-derived polyethylene terephthalate is polyethylene terephthalate having biomass-derived ethylene glycol as a diol unit and fossil fuel-derived terephthalic acid as a dicarboxylic acid unit.

  The second base material layer is a resin layer containing polyamide. The second base material layer is preferably stretched and is preferably biaxially stretched. Examples of the polyamide include nylon 6, nylon 6,6, nylon 9, nylon 11, nylon 12, nylon 6/66, nylon 66/610, nylon MXD6, and the like. By providing a polyamide resin layer inferior in water resistance as the second layer inside the laminated body instead of outside, the strength required of the packaging bag can be improved without impairing the water resistance.

When the first substrate layer is a stretched polyethylene terephthalate film, the stretched polyethylene terephthalate film used for the first substrate layer has a tensile strength in the MD direction of preferably 150 MPa or more and 300 MPa or less, more preferably 200 MPa or more and 300 MPa or less, In the TD direction, preferably 150 MPa or more and 300 MPa or less, more preferably 150 MPa or more and 300 MPa or less, and the tensile elongation is preferably 50% or more and 250% or less, more preferably 70% or more and 200% or less in the MD direction. In the TD direction, it is preferably 50% or more and 250% or less, more preferably 60% or more and 200% or less.
When the second base material layer is a stretched nylon film, the stretched nylon film used for the second base material layer has a tensile strength in the MD direction, preferably 150 MPa to 350 MPa, more preferably 200 MPa to 300 MPa, TD direction. Preferably, it is 150 MPa or more and 400 MPa or less, more preferably 200 MPa or more and 350 MPa or less, and the tensile elongation is preferably 50% or more and 200% or less, more preferably 70% or more and 150% or less in the MD direction. In the TD direction, it is preferably 30% to 200%, more preferably 50% to 150%.
The tensile strength and tensile elongation can be measured in accordance with JIS K 7127.

  Each of the first and second base material layers preferably has a thickness of 5 μm or more and 40 μm or less, more preferably 8 μm or more and 25 μm or less. The thicknesses of the first and second base material layers may be different or the same. If the thicknesses of the first and second base material layers are in the above range, the molding process is easy, and it can be suitably used as a packaging material.

[Sealant layer]
The laminate according to the present invention includes a sealant layer that is an innermost layer when a packaging bag is manufactured. The sealant layer includes biomass-derived linear low density polyethylene (LLDPE) and low density polyethylene (LDPE), and may further include a linear low density polyethylene derived from fossil fuel. Further, the low density polyethylene may be derived from biomass or derived from fossil fuel.

  Low-density polyethylene has a lower softening point than linear low-density polyethylene, and when the sealant layer is formed only of low-density polyethylene, the boil resistance may be inferior. On the other hand, when the sealant layer does not contain any low density polyethylene, it may be inferior to hand cutting when a packaging bag is manufactured. In the present invention, the sealant layer contains both biomass-derived linear low-density polyethylene and low-density polyethylene, so that it is possible to achieve both excellent boil sterilization resistance and excellent hand cutting properties when a packaging bag is manufactured. it can. The softening point of the low density polyethylene is usually 80 to 100 ° C., preferably 85 to 95 ° C., and the softening point of the linear low density polyethylene is usually 90 to 120 ° C., preferably It is 105-115 degreeC.

  The content of the low-density polyethylene in the sealant layer (when two types derived from biomass and fossil fuel are included, the total content) is 5% by mass or more and 25% by mass or less, preferably 10% by mass or more and 20% by mass or less. It is. In addition, the content of the linear low density polyethylene derived from biomass and / or fossil fuel in the sealant layer (when two types are included, the total content) is preferably 75% by mass to 95% by mass, and more Preferably they are 80 mass% or more and 90 mass% or less. By mixing the low density polyethylene and the linear low density polyethylene in the above ratio in the sealant layer, it is possible to achieve both excellent boil resistance and excellent hand cutting properties when the packaging bag is manufactured.

  The sealant layer preferably has a biomass degree of 5% to 30%, more preferably 10% to 25%, and still more preferably 15% to 20%. In addition, in this invention, "biomass degree" shows the weight ratio of a biomass origin component. If the degree of biomass is in the above range, the amount of fossil fuel used can be reduced while reducing costs, and the environmental load can be reduced.

The “biomass degree” (carbon concentration derived from biomass) is a value of C14 content obtained by a radioactive carbon (C14) measurement method based on ASTM-D6866. Since carbon dioxide in the atmosphere contains C14 at a constant ratio (105.5 pMC), the C14 content in plants that grow by incorporating carbon dioxide in the atmosphere, for example, corn, is also about 105.5 pMC. It is known. It is also known that fossil fuel contains almost no C14. Therefore, the proportion of carbon derived from biomass can be calculated by measuring the proportion of C14 contained in all carbon atoms in the sealant layer. In the present invention, the biomass-derived carbon content Pbio when the content of C14 in the sealant layer is PC14 can be obtained as follows.
Pbio (%) = PC14 / 105.5 × 100
Note that PMC is an abbreviation for Percent Modern Carbon.

  Biomass polyethylene is a monomer polymer containing biomass-derived ethylene. Since ethylene derived from biomass is used as a monomer as a raw material, the polymerized polyolefin is derived from biomass. The content of ethylene derived from biomass in the raw material monomer is not necessarily 100% by mass, and is preferably 50% or more, more preferably 80% or more, for example. The raw material monomer may contain fossil fuel-derived ethylene, and may contain α-olefin monomers such as butylene, hexene, and octene. Even in such a case, the obtained polymer is called biomass polyethylene. By including an α-olefin, the polymerized polyolefin has an alkyl group as a branched structure, and therefore can be more flexible than a simple linear one.

  For example, biomass-derived ethylene can be produced using biomass-derived ethanol as a raw material. In particular, it is preferable to use biomass-derived fermented ethanol obtained from plant raw materials. A plant raw material is not specifically limited, A conventionally well-known plant can be used. For example, corn, sugar cane, beet, and manioc can be mentioned.

  In the present invention, biomass-derived fermented ethanol refers to ethanol that has been purified after contacting a microorganism-producing product or a crushed product thereof with a culture solution containing a carbon source obtained from plant raw materials. For the purification of ethanol from the culture solution, conventionally known methods such as distillation, membrane separation, and extraction can be applied. For example, a method of adding benzene, cyclohexane or the like and azeotropically or removing water by membrane separation or the like can be mentioned.

  Linear low density polyethylene is obtained by polymerizing ethylene and a small amount of α-olefin by low pressure polymerization (gas phase polymerization using Ziegler-Natta catalyst or liquid phase polymerization using metallocene catalyst). . The low density polyethylene is obtained by polymerizing ethylene by a high pressure polymerization method. Linear low density polyethylene has many short molecular chains in the molecular chain and is excellent in sealing performance.

Linear low density polyethylene and low density polyethylene 0.93 g / cm less than ^3, preferably 0.91 g / cm ³ or more 0.93 g / cm less than ^3, more preferably 0.912 g / cm ³ or more 0.928 g / cm ³ or less, more preferably those having a density of 0.915 g / cm ³ or more 0.925 g / cm ³ or less. The MFR of linear low density polyethylene may be lower than the MFR of low density polyethylene. The density of the linear low density polyethylene and the low density polyethylene is a value measured according to the method defined in Method A of JIS K7112-1980 after annealing described in JIS K6760-1995. If the density of the linear low density polyethylene and the low density polyethylene is 0.91 g / cm ³ or more, the rigidity of the sealant layer containing the linear low density polyethylene and the low density polyethylene can be increased, and the inner layer of the packaging bag It can be used suitably. Moreover, if the density of linear low density polyethylene and low density polyethylene is less than 0.93 g / cm < ³ >, the mechanical strength of a sealant layer can be raised and it can use suitably as an inner layer of a packaging bag.

  The linear low density polyethylene and the low density polyethylene are 0.1 g / 10 min or more and 10 g / 10 min or less, preferably 0.2 g / 10 min or more and 9 g / 10 min or less, more preferably 1 g / 10 min or more and 8. It has a melt flow rate (MFR) of 5 g / 10 min or less. The MFR of linear low density polyethylene may be lower than the MFR of low density polyethylene. The melt flow rate is a value measured by the method A under the conditions of a temperature of 190 ° C. and a load of 21.18 N in the method defined in JIS K7210-1995. If the MFR of the linear low density polyethylene and the low density polyethylene is 0.1 g / 10 min or more, the extrusion load during the molding process can be reduced. Moreover, if the MFR of the linear low density polyethylene and the low density polyethylene is 10 g / 10 min or less, the mechanical strength of the sealant layer can be increased.

In the present invention, biomass polyethylene suitably used is a biomass-derived linear low-density polyethylene (trade name: SLL118, density: 0.916 g / cm ³ , MFR: 1.0 g / 10 minutes) manufactured by Braschem. , Biomass degree 87%), biomass-derived linear low density polyethylene (trade name: SLL318, density: 0.918 g / cm ³ , MFR: 2.7 g / 10 min, biomass degree 87%), A linear low-density polyethylene derived from biomass manufactured by Braschem (trade name: SLH218, density: 0.916 g / cm ³ , MFR: 2.3 g / 10 min, biomass degree 87%), derived from biomass manufactured by Braschem low-density polyethylene (trade name: SBC818, ^{density: 0.918g / cm 3, MFR:} 8.1g / 10 minutes, Biomass of 95%), Braskem manufactured by low-density polyethylene (trade name derived biomass: SPB681, ^{Density: 0.922g / cm 3, MFR:} 3.8g / 10 min, the biomass of 95%), manufactured by Braskem Inc. Biomass-derived low density polyethylene (trade name: STN7006, density: 0.923 g / cm ³ , MFR: 0.6 g / 10 min, biomass degree 95%), and the like.

  Biomass-derived linear low-density polyethylene is produced, for example, using sugarcane as a raw material. The degree of dispersion of such a low-density polyethylene derived from sugarcane can be 4 or more and 7 or less. On the other hand, the degree of dispersion of the fossil-derived linear low-density polyethylene is usually from 1.5 to 3.5.

  The sealant layer preferably has a thickness of 30 μm to 90 μm, more preferably 40 μm to 80 μm, and still more preferably 50 μm to 70 μm. If the thickness of the sealant layer is in the above range, it is possible to achieve both excellent boil sterilization resistance and excellent hand cutting properties when a boil sterilization packaging bag is manufactured.

[Transparent deposition layer]
A transparent vapor deposition layer is a layer which consists of a vapor deposition film of an inorganic oxide. The vapor deposition film can be formed by a conventionally known method, and the composition and formation method of the inorganic oxide are not particularly limited. By providing the transparent vapor-deposited layer, the laminated body is transparent, so that 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. In addition, a laminated body may be provided with two or more transparent vapor deposition layers. When two or more transparent vapor deposition layers are provided, each may have the same composition or a different composition.

  Examples of the deposited film include silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B), and titanium (Ti). ), Lead (Pb), zirconium (Zr), yttrium (Y), and the like. 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 inorganic oxide vapor-deposited film varies depending on the kind of the inorganic oxide to be used and the like, but it is arbitrarily selected and formed within a range of, for example, 50 to 2000 mm, preferably 100 to 1000 mm. Is desirable. 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 transparent vapor deposition film. The gas barrier coating film is a layer 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.

[Print 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 1st base material layer and a metal vapor deposition layer. The print layer may be provided on the entire surface of the first 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.

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

<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 and a sand 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.

<Packaging bag>
The packaging bag by this invention is equipped with the said laminated body, and can be used conveniently for boil sterilization. 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.

The packaging bag by this invention is demonstrated referring drawings. An example of a schematic front view of a boil sterilization pouch according to the present invention is shown in FIG.
The pouch 30 shown in FIG. 3 is manufactured in a standing pouch type, and the sealant layers of the wall surface films (using the above laminate) 31 and 31 ′ are arranged to face each other, and the wall surface films 31 and 31 ′. A bottom film (which may be the same as or different from the wall film) 32 is inserted in a state of being folded in the middle between the lower parts of the bottom, and is formed into a form having a gusset part, and includes a ship bottom shape including a peripheral part The bottom seal portion 33 is heat sealed to form the bottom. At this time, a notch portion of a substantially semicircular bottom sheet may be provided in the vicinity of the lower ends of both sides of the bottom film 32 that is folded in a mountain, so that the bottom seal portion 33 is formed. Next, both side edge portions of the wall surface films 31, 31 ′ are heat-sealed by the side seal portion 34 to form a body portion, and the upper end portion is left as a filling port for contents. And the upper seal part 35 provided in the filling port of the upper end part is sealed by heat sealing with, for example, a deaeration seal after filling the contents from this part.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to the following examples.

[Example 1]
<Preparation of laminated body 1>
Aluminum oxide was deposited on the biaxially stretched polyethylene terephthalate film (thickness 12 μm) by the PVD method. Next, to a mixed solution composed of polyvinyl alcohol, isopropyl alcohol, and ion-exchanged water of composition a prepared according to the composition table shown below, ethyl silicate, silane coupling agent, isopropyl alcohol, hydrochloric acid, and A hydrolyzed solution composed of ion-exchanged water was added and stirred to obtain a colorless and transparent gas barrier coating solution. The obtained gas barrier coating solution was coated on the vapor deposition surface of the polyethylene terephthalate film to form a gas barrier coating film.
Composition table a
Polyvinyl alcohol 2.30
Isopropyl alcohol 2.70
H ₂ O 51.20
b
Ethyl silicate 16.60
Silane coupling agent 0.20
Isopropyl alcohol 3.90
0.5N hydrochloric acid aqueous solution 0.50
H ₂ O 22.60
Total 100.00 (wt%)

Subsequently, a printing layer was formed on the gas barrier coating film by gravure printing. Next, a printing surface of the polyethylene terephthalate film and a biaxially stretched nylon film (thickness 15 μm, manufactured by Unitika Co., Ltd., Emblem ONMB) are combined with a two-component curable adhesive (manufactured by Rock Paint Co., Ltd., RU-40). / H-5) to obtain a laminated film. In addition, 60 parts by mass of fossil fuel-derived linear low density polyethylene (softening point: 108 ° C., density: 0.918 g / cm ³ , MFR: 3.8 g / 10 min, biomass degree: 0%), fossil fuel Low-density polyethylene (softening point: 93 ° C., density: 0.924 g / cm ³ , MFR: 2.0 g / 10 min, biomass degree: 0%) 20 parts by mass, and linear low-density polyethylene derived from biomass (Softening point: 112 ° C., manufactured by Brasschem, trade name: SLL118, density: 0.916 g / cm ³ , MFR: 1.0 g / 10 min, biomass degree 87%) A composition was obtained. Subsequently, the obtained resin composition was formed into a film by a top-blown air-cooled inflation co-extrusion film forming machine to obtain a polyethylene film 1 for a sealant layer (thickness 60 μm, biomass degree: 17.4%). Next, the nylon film surface of the laminated film and the polyethylene film 1 are bonded together using a two-component curable adhesive (Rock Paint Co., Ltd., RU-40 / H-5), and the first substrate A laminate 1 was obtained in which a layer, a transparent vapor deposition layer, a gas barrier coating film, a printing layer, an adhesive layer, a second base material layer, an adhesive layer, and a sealant layer were sequentially laminated.

[Example 2]
<Preparation of laminated body 2>
The blend of the polyethylene film 1 for the sealant layer is added to 70 parts by mass of linear low density polyethylene derived from fossil fuel, 10 parts by mass of low density polyethylene derived from fossil fuel, and 20 parts by mass of linear low density polyethylene derived from biomass. Except having changed, it carried out similarly to Example 1, and obtained the laminated body 2. FIG.

[Example 3]
<Preparation of laminate 3>
The blend of the polyethylene film 1 for the sealant layer is added to 55 parts by mass of linear low density polyethylene derived from fossil fuel, 25 parts by mass of low density polyethylene derived from fossil fuel, and 20 parts by mass of linear low density polyethylene derived from biomass. Except having changed, it carried out similarly to Example 1, and obtained the laminated body 3. FIG.

[Comparative Example 1]
<Preparation of laminate 4>
The blend of the polyethylene film 1 for the sealant layer is added to 10 parts by mass of linear low density polyethylene derived from fossil fuel, 70 parts by mass of low density polyethylene derived from fossil fuel, and 20 parts by mass of linear low density polyethylene derived from biomass. Except having changed, it carried out similarly to Example 1, and obtained the laminated body 4.

[Comparative Example 2]
<Preparation of laminated body 5>
Except for changing the blend of the polyethylene film 1 for the sealant layer to 80 parts by mass of linear low density polyethylene derived from fossil fuel and 20 parts by mass of linear low density polyethylene derived from biomass, the same as in Example 1, A laminate 5 was obtained.

<Manufacture of pouches>
The laminate obtained in Example 1 was used as a wall film and a bottom film, and the sealant layers were heat sealed to produce a standing pouch shown in FIG. Similarly, the standing pouch shown in FIG. 3 was produced using the laminated body obtained in Examples 2-3 and Comparative Examples 1-2.

<Boil sterilization resistance test>
Each pouch obtained above was vacuum-filled with beans and boiled at 95 ° C. for 30 minutes, and whether or not the inner surfaces of the films were welded was evaluated according to the following criteria. The evaluation results are shown in Table 1.
(Evaluation criteria)
○: The films on the inner surface of the pouch were not welded.
X: The films on the inner surface of the pouch were welded together.

<Hand cutting test>
Three standing pouches shown in FIG. 3 each prepared in the same manner as described above were prepared using the laminates obtained in the examples and comparative examples. Subsequently, the hand cutting property when the standing pouch was cut was confirmed.
(Evaluation criteria)
○: All three samples could be cut without applying excessive force.
X: Even one sample could not be cut unless excessive force was applied.

The results of the performance evaluation test are shown in Table 1.

DESCRIPTION OF SYMBOLS 10, 20 Laminate 11, 21 1st base material layer 12, 22 2nd base material layer 13, 23 Sealant layer 24 Transparent vapor deposition layer 25 Gas barrier coating film 26 Print layer 27, 28 Adhesive layer 30 Packaging bag 31, 31 ' Wall film 32 Bottom film 33 Bottom seal part 34 Side seal part 35 Upper seal part

Claims (10)

At least a laminate for boil sterilization comprising a first base material layer, a second base material layer, and a sealant layer in this order,
The first base layer includes polyethylene terephthalate,
The second substrate layer comprises polyamide;
The sealant layer includes biomass-derived linear low density polyethylene and low density polyethylene,
The laminated body whose content of the low density polyethylene in the said sealant layer is 5 to 25 mass%.   The laminated body of Claim 1 in which the said sealant layer further contains the linear low density polyethylene derived from a fossil fuel.   The laminate according to claim 2, wherein the sealant layer contains a total of 75% by mass or more and 95% by mass or less of linear low density polyethylene derived from the biomass and / or fossil fuel.   The laminated body as described in any one of Claims 1-3 whose biomass degree of the said sealant layer is 5% or more and 30% or less.   The laminate according to any one of claims 1 to 4, wherein the laminate further comprises a transparent vapor deposition layer between the first substrate layer and the second substrate layer.   The laminate according to claim 5, wherein the transparent vapor deposition layer is an aluminum oxide vapor deposition layer.   The laminate according to claim 5 or 6, wherein the laminate further comprises a gas barrier coating film between the transparent vapor deposition layer and the second base material layer.   The laminate according to any one of claims 1 to 7, wherein the laminate further comprises a printing layer between the first substrate layer and the second substrate layer.   The laminate according to any one of claims 1 to 8, wherein the laminate further comprises an adhesive layer between the first base material layer and the second base material layer and / or between the second base material layer and the sealant layer. The laminate according to claim 1.   A packaging bag for boil sterilization, comprising the laminate according to any one of claims 1 to 9.

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