JP2021070259A - Laminated film, method for producing the same and use of the same - Google Patents

Abstract

To provide a laminated film having excellent adhesive force between a barrier layer and an adhesion layer adjacent to the barrier layer.SOLUTION: There is provided a laminated film which has a barrier layer and an adhesion layer adjacent to the barrier layer, wherein the adhesion layer is composed of an adhesion layer composition containing 50 to 95 pts.mass of an ethylene-based polymer (X) having a density of 890 to 950 kg/m3 and an MFR (at 190°C and a load of 2.16 kg) of 1 to 50 g/10 min and 5 to 50 pts.mass of an acid-modified propylene-based polymer (Y) (provided that the total amount of (X) and (Y) is 100 pts.mass).SELECTED DRAWING: None

Description

The present invention relates to a laminated film, and more particularly to a laminated film that can be preferably used as a barrier film.

Packaging materials made of laminated plastic film are lightweight, airtight, strong, convenient to handle, and can be sealed by heat sealing, so they are used for packaging a wide variety of products such as foods and pharmaceuticals. .. The packaging material may be required to have a function of preventing quality deterioration of the contents, and depending on the contents, high oxygen gas barrier property, moisture resistance and the like are required.

Various laminated plastic films having these performances have been developed. For example, in Patent Document 1, a plastic film, a thin film layer of a gas barrier inorganic substance (aluminum oxide, etc.), a modified polyethylene composition layer, and a polyethylene film are laminated in this order. A laminated film that is difficult to permeate oxygen gas and water vapor is disclosed.

In Patent Document 2, a biaxially stretched polypropylene (OPP) film, an undercoat layer, a gas barrier layer, a coating layer made of aluminum oxide or the like, an adhesive layer made of modified polyolefin or the like, and a protective layer made of a polyolefin film are sequentially laminated. Therefore, a polyolefin film laminate that is difficult to permeate oxygen gas and water vapor is disclosed.

Further, Patent Document 3 describes a gas barrier laminated film containing an adhesive resin composition layer containing a modified ethylene / α-olefin copolymer and an unmodified ethylene / α-olefin copolymer, and a gas barrier resin layer. It is disclosed.

Japanese Unexamined Patent Publication No. 2004-142390 Japanese Unexamined Patent Publication No. 2001-315250 JP-A-2018-171807

However, the conventional barrier laminated film has room for further improvement from the viewpoint of the adhesive force between the barrier layer made of aluminum foil or the like and the adjacent adhesive layer.

As a result of diligent research, the present inventors have found that the above problems can be solved by forming an adhesive layer from a composition containing an unmodified polyolefin and a modified propylene-based polymer, and have completed the present invention.

The present invention relates to, for example, the following [1] to [8].
[1]
It has a barrier layer and an adhesive layer in contact with the barrier layer.
The adhesive layer is 50 ethylene-based polymer (X) having a density of 890 to 950 kg / m ³ and a melt flow rate (according to ASTM D1238, 190 ° C., 2.16 kg load) of 1 to 50 g / 10 minutes. ~ 95 parts by mass, and 5 to 50 parts by mass of the acid-modified propylene-based polymer (Y) (however, the total amount of the ethylene-based polymer (X) and the acid-modified propylene-based polymer (Y) is 100 parts by mass. A laminated film comprising an adhesive layer composition containing.).

[2]
The acid-modified propylene polymer (Y)
A propylene-based polymer having a melting point of less than 120 ° C. or not observed by a differential scanning calorimeter and a triad tacticity (mm fraction) of 85% or more measured by ^{13 C-NMR.} y-1) 50 to 95% by mass,
5 to 50% by mass of polypropylene (y-2) having a melting point of 120 to 180 ° C. measured by a differential scanning calorimeter (however, the total of (y-1) and (y-2) is 100% by mass). The laminated film according to the above [1], which is obtained by modifying a propylene composition comprising

[3]
The laminated film of the above [1] or [2] in which the barrier layer is made of an inorganic substance.
[4]
The laminated film of the above [1] or [2], wherein the barrier layer comprises at least one selected from the group consisting of polyester, polyamide and ethylene / vinyl alcohol copolymer.

[5]
The laminated film according to any one of [1] to [4], further comprising a base material layer laminated in the order of a base material layer / the barrier layer / the adhesive layer.

[6]
The laminated film according to any one of [1] to [5], further comprising a heat-sealing layer laminated in the order of the barrier layer / the adhesive layer / the heat-sealing layer.

[7]
A package containing the laminated film according to any one of [1] to [6].
[8]
The method for producing a laminated film according to the above [1], wherein the barrier layer and the adhesive layer are laminated by an extrusion lamination method.

The laminated film of the present invention containing a flexible modified propylene-based polymer in the adhesive layer has excellent adhesive force between the barrier layer and the adhesive layer adjacent thereto.

Hereinafter, the present invention will be described in more detail.
The laminated film according to the present invention has a barrier layer and an adhesive layer.
The laminated film according to the present invention may further have a base material layer laminated in the order of a base material layer / the barrier layer / the adhesive layer, and may be a barrier layer / the adhesive layer / the heat seal layer. It may have a heat seal layer laminated in order.

(Base layer)
Since the base material layer is flexible and has high transparency, a polyester film such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), and a polyamide film such as nylon 6 and nylon 66 are used. , Ethylene / vinyl alcohol copolymer film, polyolefin film such as polyethylene and polypropylene, polyimide film, etc. are preferable, and since they are excellent in physical properties such as transparency, heat resistance and mechanical strength, polyethylene terephthalate (PET) or polypropylene is used. A biaxially stretched film is more preferable, and a biaxially stretched polyethylene terephthalate film is further preferable.

The base material layer may contain additives that are usually contained in the base material layer of the barrier laminated film, as long as the effects of the present invention are not impaired.
The thickness of the base material layer is usually 3 to 100 μm, preferably 8 to 50 μm, and more preferably 10 to 30 μm.

(Barrier layer)
The barrier layer is arranged so as to be in contact with the adhesive layer.
The barrier layer prevents or suppresses the permeation of gases such as oxygen, water vapor, and odor. Further, the barrier layer also prevents light transmission by selecting an opaque material.

The barrier layer is made of an inorganic substance, for example, a metal or an inorganic oxide, or at least one resin selected from the group consisting of polyester, polyamide and ethylene / vinyl alcohol copolymer, and is made of at least one resin from the viewpoint of versatility. , Preferably composed of the above-mentioned inorganic substance.

Examples of the barrier layer made of an inorganic substance include a foil and a thin-film film formed on the surface of the base material layer.
Examples of the metal constituting the barrier layer include aluminum, copper, nickel, gold, silver, and stainless steel. From the viewpoint of versatility, aluminum is preferable, and aluminum foil is mainly used.

When the barrier layer is a vapor-deposited film, examples of the material thereof include metals such as aluminum and inorganic oxides such as aluminum oxide and silicon oxide, preferably aluminum, from the viewpoint of versatility.

The thickness of the metal foil is usually 1 to 30 μm, preferably 5 to 15 μm, and the thickness of the vapor-deposited layer is usually 10 to 2000 nm, preferably 20 to 100 nm.
When the barrier layer is a metal foil, for example, the matte surface of the metal foil (for example, aluminum foil) is directed toward the base material layer side, and if necessary, an adhesive (for example, a urethane-based adhesive) is used. The barrier layer can be manufactured by laminating the metal foil on the base material layer by the dry lamination method. When the barrier layer is manufactured by this method, the glossy surface of the metal foil comes into contact with the adhesive layer.

The vapor-deposited film can be formed by depositing a metal or other inorganic substance on the surface of the base material layer by a conventionally known method.
All or part of the surface of the barrier layer made of the metal may be oxidized.

When the barrier layer is made of the resin, examples of the polyester include polyethylene terephthalate.
Examples of the polyamide include nylon 6, nylon 66, nylon 6/10, nylon 12, nylon 11, MXD nylon, amorphous nylon, and terephthalic acid / adipic acid / hexamethylenediamine copolymers.

Examples of the ethylene / vinyl alcohol copolymer include copolymers in which the content of structural units derived from ethylene is preferably 15 to 70 mol%, more preferably 20 to 50 mol%.
The thickness of the barrier layer made of the resin is usually 1 to 30 μm, preferably 5 to 15 μm.

(Adhesive layer)
The adhesive layer comprises an adhesive layer composition containing an ethylene-based polymer (X) and an acid-modified propylene-based polymer (Y).

The proportions of the ethylene polymer (X) and the acid-modified propylene polymer (Y) are 50 to 95 parts by mass and 5 to 50 parts by mass, respectively (however, the ethylene polymer (X) and the acid-modified propylene). The total amount of the system polymer (Y) is 100 parts by mass), preferably 50 to 90 parts by mass and 10 to 50 parts by mass. Since the adhesive layer contains the acid-modified propylene-based polymer (Y) in a proportion of the lower limit value or more, the adhesive layer is excellent in adhesive strength with the barrier layer.

<Ethylene polymer (X)>
The density of the ethylene polymer (X) is 890 to 950 kg / m ³ , preferably 895 to 940 kg / m ³ , and more preferably 900 to 930 kg / m ³ .

The melt flow rate of the ethylene polymer (X) (according to ASTM D1238, 190 ° C., 2.16 kg load) is 1 to 50 g / 10 minutes, preferably 2 to 25 g / 10 minutes, more preferably 3 to 20 g / min. 10 minutes.

Examples of the ethylene-based polymer (X) include an ethylene homopolymer and a copolymer of ethylene and an α-olefin having 3 or more carbon atoms. The copolymer is usually a random copolymer.

The α-olefin has preferably 3 to 10 carbon atoms, more preferably 3 to 8 carbon atoms.
Examples of the α-olefin include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene and 1-octene.

The ethylene-based polymer (X) may be used alone or in combination of two or more.
The ethylene-based polymer (X) is not acid-modified, unlike the acid-modified propylene polymer (Y) described below.

<Acid-modified propylene polymer (Y)>
The acid-modified propylene-based polymer (Y) is a propylene polymer (which may be a composition of two or more kinds of propylene polymers) modified with an unsaturated carboxylic acid or a derivative thereof.

The density of the acid-modified propylene-based polymer (Y) is preferably 850 to 930 kg / m ³ , more preferably 855 to 920 kg / m ³ , and even more preferably 860 to 910 kg / m ³ .

The melt flow rate of the acid-modified propylene-based polymer (Y) (according to ASTM D1238, 230 ° C., 2.16 kg load) is preferably 0.01 to 1000 g / 10 minutes, more preferably 0.1 to 500 g /. It is 10 minutes, more preferably 1 to 200 g / 10 minutes.

Examples of the propylene polymer include a propylene homopolymer and a copolymer of propylene and ethylene and / or an α-olefin having 4 or more carbon atoms.
The α-olefin has preferably 4 to 10 carbon atoms, more preferably 4 to 8 carbon atoms.

Examples of the α-olefin include 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene and 1-octene.
The α-olefin may be used alone or in combination of two or more.

Specific examples of the propylene-based polymer (before modification) include, for example, a propylene homopolymer, a propylene / ethylene copolymer, a propylene / ethylene / 1-butene copolymer, a propylene / 1-octene copolymer, and a propylene / octene copolymer. Examples thereof include an ethylene / 1-octene copolymer and a propylene / 1-butene / 1-octene copolymer. In the case of a copolymer, the propylene-based polymer is usually a random copolymer.

In the case of a copolymer, the propylene-based polymer contains a propylene-derived structural unit as a main component (50% by mass or more with respect to all the structural units).
Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, and itaconic acid.

Examples of the derivatives include maleic anhydride, endic acid anhydride (cis-5-norbornene-endo-2,3-dicarboxylic acid anhydride), itaconic anhydride, citraconic anhydride and other acid anhydrides;
Methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, glycidyl acrylate, monoethyl maleic acid ester, diethyl maleic acid, monomethyl fumarate, dimethyl fumarate, monomethyl itaconic acid ester, diethyl itaconic acid Etc .;
Acrylamide, methacrylamide, maleic acid monoamide, maleic acid diamide, maleic acid-N-monoethylamide, maleic acid-N, N-diethylamide, maleic acid-N-monobutylamide, maleic acid-N, N-dibutylamide, Amides such as fumaric acid monoamide, fumaric acid diamide, fumaric acid-N-monobutylamide, fumaric acid-N, N-dibutylamide;
Imides such as maleimide, N-butyl maleimide, N-phenylmaleimide;
Examples thereof include metal salts such as sodium acrylate, sodium methacrylate, potassium acrylate, and potassium methacrylate.

Among these unsaturated carboxylic acids and their derivatives, maleic acid and maleic anhydride are preferable, and maleic anhydride is more preferable.
The acid-modified propylene-based polymer (Y) may be used alone or in combination of two or more.

As a preferred embodiment of the acid-modified propylene-based polymer (Y), for example, the melting point measured by a differential scanning calorimeter (hereinafter, also referred to as “DSC”) under the following conditions is less than 120 ° C. or observed. A propylene-based polymer (y) having a triad tacticity (mm fraction) of 85% or more as measured by ¹³ C-NMR under the conditions described in [0294] of International Publication No. 2006/57361. -1) 50 to 95% by mass of polypropylene (y-2) having a melting point of 120 to 180 ° C. as measured by DSC under the following conditions (where (y-1) and (y-2) ) Is 100% by mass), and the propylene-based polymer composition is modified with an acid anhydride.

As the propylene-based polymer (y-1), a copolymer of the above-mentioned propylene and ethylene and / or an α-olefin having 4 or more carbon atoms (for example, a propylene / ethylene / 1-butene random copolymer) can be used. Can be mentioned.

The melting point of the propylene-based polymer (y-1) measured under the following conditions is less than 120 ° C. or not observed, preferably 110 ° C. or less or not observed.
The triad tacticity of the propylene-based polymer (y-1) is 85% or more, preferably 87% or more, and the upper limit thereof is, for example, 98%.

Examples of the polypropylene (y-2) include a propylene homopolymer, but a small amount of a monomer other than propylene may be copolymerized.
The melting point of the polypropylene (y-2) measured under the following conditions is 120 to 180 ° C, preferably 120 to 170 ° C.

<< Measurement conditions for melting point >>
In the DSC measuring device, the sample is heated to 200 ° C. at a heating rate of 100 ° C./min, held at 200 ° C. for 10 minutes, then lowered to −150 ° C. at a temperature lowering rate of 10 ° C./min, and then raised. A heat generation / endothermic curve is created by raising the temperature at a speed of 10 ° C./min, and the temperature at the maximum melting peak position is used as the melting point.

The proportions of the propylene-based polymer (y-1) and the polypropylene (y-2) are 50 to 95% by mass and 5 to 50% by mass, preferably 60 to 90% by mass and 10 to 40% by mass, respectively. is there.

The melt flow rates of the propylene-based polymer (y-1) and the polypropylene (y-2) are appropriately set so that the melt flow rate of the acid-modified propylene-based polymer (Y) falls within the above range.

Modification of the propylene-based polymer with an unsaturated carboxylic acid or a derivative thereof can be carried out by a conventionally known method. For example, by adding an additive described later as necessary to the propylene-based polymer and graft-polymerizing an unsaturated carboxylic acid or a derivative thereof (for example, maleic acid or an anhydride thereof) in the presence of a radical initiator. , The acid-modified propylene-based polymer (Y) can be obtained.

The amount of the unsaturated carboxylic acid or its derivative charged is usually 0.010 to 15 parts by mass, preferably 0.010 to 5.0 parts by mass with respect to 100 parts by mass of the propylene-based polymer before modification. The amount of the radical initiator used is usually 0.0010 to 1.0 parts by mass, preferably 0.0010 to 0.30 parts by mass with respect to 100 parts by mass of the propylene-based polymer before modification.

Radical initiators include, for example, organic peroxides, azo compounds and metal hydrides. The radical initiator may be used as it is by mixing it with a propylene-based polymer before modification, an unsaturated carboxylic acid or a derivative thereof, and other optional components as it is, or it may be used after being dissolved in a small amount of an organic solvent. Good. The organic solvent is not particularly limited as long as it is an organic solvent capable of dissolving the radical initiator.

The graft modification can be carried out by a conventionally known method, for example, a propylene-based polymer before modification is dissolved in an organic solvent, and an unsaturated carboxylic acid or a derivative thereof and a radical initiator are added to the obtained solution. And the like, and the reaction is carried out at a temperature of 70 to 200 ° C., preferably 80 to 190 ° C. for 0.5 to 15 hours, preferably 1 to 10 hours.

Further, in an apparatus such as an extruder, an acid-modified propylene-based polymer (Y) is obtained by reacting an unsaturated carboxylic acid or a derivative thereof with a pre-modified propylene-based polymer in the presence of a radical initiator without using a solvent. May be manufactured. This reaction is usually carried out at a temperature equal to or higher than the melting point of the propylene-based polymer before modification for 0.5 to 10 minutes.

The degree of acid modification of the acid-modified propylene-based polymer (Y) defined by the following formula and measured by the method adopted in the examples described later is preferably 0.1 to 5% by mass, more preferably 0.3. ~ 2% by mass.
Acid denaturation degree (graft amount) (mass%) = (mass of a structural unit having a structure derived from a monomer having an ethylenically unsaturated group and a polar functional group in one molecule) / (acid-modified propylene-based polymer) (Y) mass) x 100

The adhesive layer composition may contain additives that are usually contained in the adhesive layer of the barrier laminated film, as long as the effects of the present invention are not impaired.
The thickness of the adhesive layer is usually 1 to 100 μm, preferably 5 to 80 μm, and more preferably 10 to 50 μm.

(Heat seal layer)
The laminated film of the present invention may be provided with a heat seal layer in the order of any base material layer / barrier layer / adhesive layer / heat seal layer.

The heat-sealed layer is composed of an ethylene-based polymer such as high-density polyethylene, low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and an ethylene / α-olefin (three or more carbon atoms) copolymer. , Single layer or multi-layer configuration may be used.

In the case of a single layer, an ethylene / α-olefin (three or more carbon atoms) copolymer is preferable as the material of the heat seal layer because heat sealing is easy, the strength is high, and the transparency is high. The ethylene / α-olefin is a random copolymer of ethylene and α-olefin, and the α-olefin is preferably an α-olefin having 3 to 12 carbon atoms, preferably 3 to 10 carbon atoms. Examples thereof include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene and 1-octene. Specific examples of the copolymer include ethylene / propylene copolymer, ethylene / 1-butene copolymer, ethylene / 4-methyl-1-pentene copolymer, ethylene / 1-hexene copolymer, and ethylene / 1. -Ocene copolymers can be mentioned.

The density of the ethylene-based polymer used in the heat-sealing layer is preferably 885 to 960 kg / m ³ , and more preferably 890 to 950 kg / m ³ .
The melt flow rate of the ethylene polymer (according to ASTM D1238, 190 ° C., 2.16 kg load) is preferably 0.5 to 50 g / 10 minutes, more preferably 1 to 30 g / 10 minutes.

The heat-sealing layer may contain additives that are usually contained in the heat-sealing layer of the barrier laminated film, as long as the effects of the present invention are not impaired.
The thickness of the heat seal layer is usually 1 to 100 μm, preferably 5 to 50 μm, and more preferably 10 to 40 μm.

(Manufacturing method of laminated film)
In the laminated film according to the present invention, any of the base material layer, the barrier layer, the adhesive layer, and any of the heat seal layers are arranged in this order so that the barrier layer is in contact with the adhesive layer. Other than that, it can be produced by adopting a conventionally known method. For example, it can be manufactured by extruding the adhesive layer onto the barrier layer using an extruded laminator.

(Use of laminated film)
The laminated film according to the present invention can be preferably used as a packaging material, particularly as a packaging material for contents such as foods and pharmaceuticals, which are required to have high oxygen gas barrier properties and moisture resistance.

Hereinafter, the present invention will be described with reference to Examples, but the present invention is not limited to the Examples.
[Measurement or evaluation method]
The physical characteristics of the raw materials and the evaluation of the laminated film were carried out by the following methods.

(Melting point of acid-modified propylene polymer (Y), etc. (measurement by reheating method))
The sample was held at 200 ° C. for 10 minutes in a DSC measuring device, cooled to -20 ° C. at a temperature lowering rate of 10 ° C./min, held at -20 ° C. for a minute, and then raised at a temperature rise rate of 10 ° C./min. The DSC curve obtained when measured in was created. The melting peak obtained at this time was taken as the melting point.

(Degree of acid denaturation of acid-modified propylene polymer (Y), etc.)
A polymer (composition) modified with maleic anhydride was heat-pressed at 250 ° C. to prepare a film, and this film was subjected to FT-IR measurement, and the peak intensity of the ^{wave number 1780 cm -1 assigned to the carbonyl group was obtained.} , And the degree of acid denaturation (graft amount) (mass%) defined by the following formula was determined based on the calibration curve prepared separately.
Acid denaturation (graft amount) (% by mass) = (mass of a structural unit having a structure derived from a monomer having an ethylenically unsaturated group and a polar functional group in one molecule) / (modified with maleic anhydride) Mass of polymer (composition) obtained) × 100

(Adhesive strength of laminated film)
The laminated film produced in the examples or comparative examples was cut out as a strip test piece having a width of 15 mm, a cut was made between the adhesive layer and the barrier layer (aluminum foil), and a tensile tester was used to make a barrier at the separated portion. The layer and the adhesive layer were gripped by chucks, and a T-type peeling test was performed at a tensile speed of 50 mm / min. The average value of the locations where a stable peeling load was shown at a peeling distance of 10 mm or more when both layers were peeled off was taken as the adhesive force.
It is known that this adhesive strength changes with time after the production of the laminated film, and in the following examples and the like, the adhesive strength one week and one month after the production of the laminated film was evaluated.

[Manufacturing Example 1]
(Manufacturing of base material layer with barrier layer)
Aluminum foil made by Toyo Aluminum K.K. (for food packaging) on Embret (registered trademark) PET-12 (biaxially stretched PET film, thickness 12 μm) manufactured by Unitika Ltd. via a urethane adhesive. Laminated normal brand (7 μm in thickness) was laminated on the matte surface side of the aluminum foil toward the biaxially stretched PET film by the dry lamination method to produce a base material layer with a barrier layer.

[Manufacturing Example 2-1]
(Manufacturing of raw materials for adhesive layer)
The resin composition was prepared according to Example 3-1 of International Publication No. 2006/57361. As a result, 20% by mass of random polypropylene having a melting point of 140 ° C. and a melt flow rate (according to ASTM D1238, 230 ° C., 2.16 kg load) of 7 g / 10 minutes, an ethylene-derived skeleton content of 13 mol%, and a propylene-derived skeleton content. The skeletal content was 67 mol% and the 1-butene-induced skeletal content was 19 mol%, and the melting point was not observed in the measurement described in [0510] of International Publication No. 2006/57361, and was measured by ^{13 C-NMR.} It is composed of 80% by mass of a propylene / ethylene / 1-butene copolymer having a triad tacticity (mm fraction) of 92% and a melt flow rate (230 ° C., 2.16 kg load) of 7 g / 10 min. A propylene resin composition was obtained. 0.6 parts by mass of maleic acid anhydride and radical initiator (2,5-dimethyl-2,5-di- (t-butylperoxy) -3-hexine (2,5-dimethyl-2,5-di- (t-butylperoxy) -3-hexine) with respect to 100 parts by mass of this propylene resin composition. The product name Perhexa 25B)) is mixed at a ratio of 0.15 parts by mass and extruded using a twin-screw extruder at a resin temperature of 200 ° C., a screw rotation speed of 250 rpm, and a discharge rate of 300 kg / hour to obtain an acid-modified propylene-based weight. An acid-modified propylene-based resin composition as a coalescence (Y) was obtained. The physical characteristics are shown in Table 1.

[Manufacturing Example 2-2]
(Manufacturing of raw materials for adhesive layer)
The propylene resin composition was changed to an ethylene / 1-butene copolymer (trade name: Toughmer (registered trademark) A-20090S, manufactured by Mitsui Chemicals, Inc.), and maleic anhydride was 0.75 parts by mass and radical. Production Example 2-except that the initiator (2,5-dimethyl-2,5-di- (t-butylperoxy) -3-hexine (trade name: Perhexa 25B)) was mixed at a ratio of 0.05 parts by mass. The same operation as in No. 1 was carried out to produce an acid-modified ethylene-based polymer (hereinafter referred to as "acid-modified EBR-1"). The physical characteristics are shown in Table 1.

[Manufacturing Example 2-3]
(Manufacturing of raw materials for adhesive layer)
The propylene-based resin composition was changed to high-pressure low-density polyethylene (trade name: Mirason (registered trademark) 16P, manufactured by Mitsui Dow Polychemical Co., Ltd.), and maleic acid anhydride was 0.75 parts by mass, a radical initiator. (2,5-Dimethyl-2,5-di- (t-butylperoxy) -3-hexine (trade name: Perhexa 25B)) was mixed with Production Example 2-1 in a proportion of 0.05 parts by mass. The same operation was carried out to produce acid-modified polyethylene (hereinafter referred to as "acid-modified LDPE"). The physical characteristics are shown in Table 1.

[Raw material for adhesive layer]
The resins shown in Table 1 were prepared as raw materials for the adhesive layer of the laminated film.

[Example 1]
A laminated film was manufactured using a coextrusion laminator consisting of two extruders. Specifically, LDPE (Mirason 16P) is extruded from one extruder for forming the outermost layer so as to have a thickness of 30 μm, and another layer for forming a layer in contact with the barrier layer (aluminum foil) is formed. From one extruder, 80 parts by mass of LDPE (Mirason 16P), which is a raw material for the adhesive layer, and 20 parts by mass of the acid-modified propylene resin composition produced in Production Example 2-1 were kneaded in the extruder. Later, on the barrier layer (aluminum foil) of the base material layer with the barrier layer obtained in Production Example 1, the thickness was set to 20 μm under the conditions of an extrusion temperature of 320 ° C. and a film forming speed of 5 m / min (both). The laminated film was formed by extruding (so that the total thickness of the extruded resin was 50 μm). Table 2 shows the evaluation results of the laminated film.

[Comparative Examples 1 to 4]
A laminated film was produced in the same manner as in Example 1 except that the raw material for forming the adhesive layer was changed as shown in Table 2. Table 2 shows the evaluation results of the laminated film.

Claims (8)

It has a barrier layer and an adhesive layer in contact with the barrier layer.
The adhesive layer is 50 ethylene-based polymer (X) having a density of 890 to 950 kg / m ³ and a melt flow rate (according to ASTM D1238, 190 ° C., 2.16 kg load) of 1 to 50 g / 10 minutes. ~ 95 parts by mass, and 5 to 50 parts by mass of the acid-modified propylene-based polymer (Y) (however, the total amount of the ethylene-based polymer (X) and the acid-modified propylene-based polymer (Y) is 100 parts by mass. A laminated film comprising an adhesive layer composition containing.). The acid-modified propylene polymer (Y)
A propylene-based polymer having a melting point of less than 120 ° C. or not observed by a differential scanning calorimeter and a triad tacticity (mm fraction) of 85% or more measured by ^{13 C-NMR.} y-1) 50 to 95% by mass,
5 to 50% by mass of polypropylene (y-2) having a melting point of 120 to 180 ° C. measured by a differential scanning calorimeter (however, the total of (y-1) and (y-2) is 100% by mass). The laminated film according to claim 1, wherein the propylene composition comprising the above is modified with an acid anhydride. The laminated film according to claim 1 or 2, wherein the barrier layer is made of an inorganic substance. The laminated film according to claim 1 or 2, wherein the barrier layer comprises at least one selected from the group consisting of polyester, polyamide and ethylene / vinyl alcohol copolymer. The laminated film according to any one of claims 1 to 4, further comprising a base material layer laminated in the order of a base material layer / the barrier layer / the adhesive layer. The laminated film according to any one of claims 1 to 5, further comprising a heat-sealing layer laminated in the order of the barrier layer / the adhesive layer / the heat-sealing layer. A package containing the laminated film according to any one of claims 1 to 6. The method for producing a laminated film according to claim 1, wherein the barrier layer and the adhesive layer are laminated by an extrusion lamination method.