WO2011099129A1

WO2011099129A1 - Composite multilayer film

Info

Publication number: WO2011099129A1
Application number: PCT/JP2010/051980
Authority: WO
Inventors: 瀬田　寧
Original assignee: リケンテクノス株式会社
Priority date: 2010-02-10
Filing date: 2010-02-10
Publication date: 2011-08-18
Also published as: JPWO2011099129A1; JP5628215B2

Abstract

A composite multilayer film comprising an aluminum layer (B) of which at least one surface has been subjected to chemical conversion coating, a polyolefin resin film (A) arranged on one surface of the aluminum layer (B) which has been subjected to the conversion coating, and a polyamide layer (C) arranged on the other surface of the aluminum layer (B), wherein the film (A) comprises a layer (A-1) comprising an acid-modified polyethylene resin (α), a layer (A-2) comprising a crystalline polyethylene resin (β) and at least one layer (A-3) which is arranged between the layers (A-1) and (A-2), Tm_α60 is smaller than Tm_β60 (wherein Tm_α60 represents a temperature at which the crystallinity degree of the acid-modified polyethylene resin (α) becomes 60%; and Tm_β60 represents a temperature at which the crystallinity degree of the crystalline polyethylene resin (β) becomes 60%), the layer (B) is laminated on the layer (A-1) directly, and the layer (A-3) comprises a resin composition (γ) having an adsorption function and comprising (a) 100 parts by mass of a polyethylene resin and (b) 1 to 300 parts by mass of a filler having an adsorption function.

Description

Composite multilayer film

The present invention relates to a multilayer film useful for housing foods and daily necessities, housing a power generation / storage element of a secondary battery or an electric double layer capacitor, and the like.

As a packaging material for storing retort foods such as curry, refill items such as shampoos and liquid detergents, and power generation elements for secondary batteries, a polyolefin film layer on one side of the aluminum foil layer and the other A composite multilayer film having a polyamide layer on the side is widely used (for example, Patent Document 1). Since polyolefin has thermal adhesiveness, it is possible to seal the packaging material by heat sealing by setting the polyolefin film to the inside of the packaging material. Moreover, polyamide is excellent in mechanical strength and can improve the durability of the packaging material.

Conventionally, the polyolefin film and the aluminum foil are bonded via an anchor coat agent or an adhesive. For this reason, it has not been possible to use a liquid having a strong permeability or a strong dissolving power that attacks the anchor coating agent or the adhesive.

Moreover, in the prior art, the aluminum foil which is not surface-treated is used. Therefore, the packaging material having an aluminum foil could not be used as a content for a liquid that corrodes aluminum even if the liquid does not affect the adhesive layer.

Further, in recent years, lithium ion secondary batteries and electric double layer capacitors have been actively studied as batteries for hybrid vehicles and electric vehicles. Conventionally, lithium ion secondary batteries and electric double layer capacitors have been made into products by enclosing their power generation / storage elements in metal cans. However, strict fuel efficiency standards are imposed on automobiles, and weight reduction is being promoted for each part. Therefore, using the composite multilayer film as an exterior material such as a secondary battery is a very promising method in terms of reducing the weight of an automobile.

As a technique for solving these problems, a method of treating the surface of an aluminum foil with a chromic acid chemical (chromate treatment) is widely known (for example, Patent Document 2). By the film formed by this treatment, the corrosion resistance of the aluminum foil is remarkably improved, and the film can be bonded to the polyolefin film by heat lamination without using any anchor coat agent or adhesive. However, this technique involves a serious problem of using chromium, which is an environmentally hazardous substance.

Non-chromium chemical conversion treatments such as boehmite treatment (hydrothermal treatment) and phosphate treatment are known as aluminum surface treatments that do not use chromium, and these surface treatments can provide the same corrosion resistance as chromate treatment. However, if an attempt is made to bond a polyolefin film and a non-chromium chemical conversion aluminum foil by thermal lamination without using an anchor coating agent or an adhesive, the polyolefin film is not fused to the processing machine. In the temperature range where lamination can be performed, sufficient adhesive strength cannot be obtained.

Furthermore, when the composite multilayer film is applied to a lithium ion secondary battery or an electric double layer capacitor for a hybrid vehicle or an electric vehicle, a high level of low temperature resistance is required. In the prior art, crystalline polypropylene is used as the polyolefin film with an emphasis on heat resistance, and the low temperature resistance is insufficient. Therefore, in order to improve the low temperature resistance, it is widely used to use a block copolymer as a crystalline polypropylene or to blend rubber or the like. However, in such a technique, since the “islands” of rubber as a low temperature resistance modifier have a morphology dispersed in the “sea” of crystalline polypropylene, the penetration of liquid from the “islands” becomes a problem. Since organic solvents used in lithium ion secondary batteries and electric double layer capacitors have strong permeability and dissolving power, there is a high risk of leakage in the long term.

In addition, lithium ion secondary batteries and electric double layer capacitors for hybrid vehicles and electric vehicles are required to have a long life of 10 years or more. When such a long life is reached, moisture penetration from the outside through the heat seal end face of the polyolefin film becomes a problem.

Further, since lithium ion secondary batteries and electric double layer capacitors use a carbonate-based organic solvent as an electrolyte or use carbon as an electrode, carbon monoxide is contained in a container in which a storage element is enclosed. Another major problem is that it has the property of easily generating gas, and as a result, the life of the container is shortened due to deformation and rupture of the container. If the battery exterior is a metal can type, it is possible to provide a gas release valve, but it is practically difficult to provide a gas release valve in the composite multilayer film type.

WO99 / 40634 pamphlet JP 2003-288865 A

An object of this invention is to provide the composite multilayer film suitable as an exterior material for enclosing the electrical storage element of the lithium ion secondary battery and electric double layer capacitor for hybrid vehicles and electric vehicles.

More specifically, in a composite multilayer film having a polyolefin film layer on one side of a surface-treated aluminum foil layer and a polyamide layer on the other side, the aluminum foil and the polyolefin film are directly bonded, that is, anchor coating agent or adhesive. Bonded with sufficient adhesive strength without applying any agent, etc., excellent in low temperature resistance, and moisture that enters from the outside through the heat seal end face of the polyolefin film and generated inside the battery An object is to provide a composite multilayer film having a function of adsorbing and removing carbon monoxide gas and the like.

The inventor of the present invention has a heat laminate layer in which a polyolefin film is made of an acid-modified polyethylene resin (α) and a specific polyethylene resin (β) having a crystal melting temperature higher than that of the resin (α). The multilayer film in which the aluminum foil is surface-treated and the aluminum foil is laminated on the thermal laminate layer is so high that the thermal laminate layer thermally laminates the polyolefin film and the aluminum foil with the aluminum foil. Even if laminated at a temperature, the polyolefin film can be bonded without causing a trouble that the polyolefin film is fused to the processing machine, and the adhesive strength between the aluminum foil and the polyolefin film layer and the low temperature resistance are excellent. I found. Further, by providing a layer (A-3) of the adsorption functional resin composition (γ) containing an adsorption functional filler having a fine particle diameter between the heat laminate layer and the heat seal layer, It has been found that a function of adsorbing and removing moisture entering from the outside through the end face of the heat seal or carbon monoxide gas generated inside the battery can be provided.

That is, the present invention has a polyolefin-based resin film (A) on one surface of the aluminum layer (B) subjected to chemical conversion treatment on at least one surface and a polyamide treatment on the other surface. In the composite multilayer film having the layer (C), the film (A) comprises an acid-modified polyethylene resin (α) layer (A-1), a crystalline polyethylene resin (β) layer (A-2), And the temperature at which the acid-modified polyethylene resin (α) has a crystallinity of 60% is _defined as Tm _α60, and the crystalline polyethylene resin has one or more layers (A-3) positioned between them. when the temperature at which crystallinity is 60% (beta) was _Tm β60, a _{_Tm} α60 <Tm β60, the layer (B) is laminated directly on the layer (a-1), a layer ( A-3)
It consists of an adsorption functional resin composition (γ) containing (a) 100 parts by mass of a polyethylene-based resin and (b) 1 to 300 parts by mass of an adsorption functional filler. Particle diameter (D99) and particle diameter (D50) of 20 μm or less, wherein D99 and D50 are respectively the particle diameters at the points where 99% by mass and 50% by mass are accumulated from the smaller particle diameter in the particle size distribution. This is a composite multilayer film.

The present invention also provides a method for producing the composite multilayer film.

In the composite multilayer film of the present invention, the polyolefin resin layer and the surface-treated aluminum layer are directly bonded with sufficient adhesive strength without applying an anchor coating agent or adhesive, and low temperature resistance In addition, it has a function of adsorbing moisture, carbon monoxide, etc., so it is useful as a packaging material for encapsulating lithium ion secondary batteries and electric double layer capacitor storage elements for hybrid and electric vehicles. It is.

FIG. 1 is an example of the composite multilayer film of the present invention.

An example of the composite multilayer film of the present invention is shown in FIG. As shown in FIG. 1, the composite multilayer film of the present invention has a polyolefin resin film (A) on one side of the aluminum layer (B) subjected to chemical conversion treatment at least on one side and on the surface subjected to chemical conversion treatment. And a polyamide layer (C) on the other surface. You may further have a layer (D) of a polyester-type resin on a layer (C). The film (A) has at least three layers, ie, an acid-modified polyethylene resin (α) layer (A-1), a crystalline polyethylene resin (β) layer (A-2), and a position between them. And the layer (A-3) of the adsorption functional resin composition (γ) to be in contact with the layer (B). The layer (A-2) is located at the innermost surface when the composite multilayer film is formed into a bag shape so that the film (A) is on the inner side.

(A) Polyolefin resin film The acid-modified polyethylene resin (α) constituting the layer (A-1) and the crystalline polyethylene resin (β) constituting the layer (A-2) When the temperatures at which the degree of crystallinity (Xc) is 60% are Tm _α60 and Tm _β60 , respectively, Tm _α60 <Tm _β60 is selected. Preferably, when the temperature at which crystallinity of the resin (beta) is 70% and _{_Tm} β70, Tm α60 <chosen to be Tm _Beta70, more preferably, crystallinity of the resin (beta) when is the temperature at which 80% was _Tm β80, it is selected to be the _{_Tm} α60 <Tm β80. When Tm _α60 ≧ Tm _β60 , troubles such as the film (A) fusing to the processing machine occur when the layer (A-1) side of the film (A) is thermally laminated with the layer (B).

The temperatures such as Tm _α60 and Tm _β60 are values determined from the DSC melting curve of the corresponding resin. For example, the temperature Tm _{β60 at} which the crystallinity of the resin (β) becomes 60% is such that the ratio of the melting enthalpy at the temperature Tm _β60 or higher to the total melting enthalpy in the DSC melting curve of the resin (β) is 60%. Means. In this specification, unless otherwise specified, DSC melting curves are obtained by using DSC Q1000 model of TA Instruments (TA Instruments Japan Co., Ltd.) and holding the sample at 230 ° C. for 5 minutes. Obtained by performing DSC measurement with a temperature program that cools to -10 ° C at a temperature drop rate of 10 ° C / minute, holds at -10 ° C for 5 minutes, and then heats to 230 ° C at a temperature rise rate of 10 ° C / minute. It is a curved line.

As described above, the acid-modified polyethylene resin (α) is selected so as to satisfy Tm _α60 <Tm _β60 . Since the layer (A-1) is a layer that is directly bonded to the chemical-treated surface of the layer (B) in the thermal lamination of the film (A) and the layer (B), the resin (α) is Tm _The lower _α60 can lower the temperature in the heat laminating process. However, since electrolytes of lithium ion secondary batteries and electric double layer capacitors have strong penetrability and dissolving power, and are required to have heat resistance and moisture permeability from the viewpoint of battery performance, Tm _α60 is preferably used. It is selected from those of 80 ° C. or higher. More preferably, Tm _α60 is 90 ° C. or higher, more preferably 100 ° C. or higher. _Further, the upper limit of Tm _α60 is preferably 130 ° C., more preferably 125 ° C. in consideration of the upper limit of heat resistance of the crystalline polyethylene resin (β) constituting the layer (A-2).

Examples of the acid-modified polyethylene resin (α) include a polyethylene resin modified with an unsaturated carboxylic acid or a derivative thereof. Resin ((alpha)) can raise the adhesive strength with the aluminum foil of a layer (B), when the polyethylene-type resin is acid-modified. Examples of unsaturated carboxylic acids include, for example, maleic acid, itaconic acid, fumaric acid, and examples of derivatives thereof include, for example, maleic acid monoester, maleic acid diester, maleic anhydride, itaconic acid monoester, Examples include itaconic acid diester, itaconic anhydride, fumaric acid monoester, fumaric acid diester, fumaric anhydride and the like. Examples of the polyethylene resin include linear polyethylene, ultra-low density polyethylene, high density polyethylene, ethylene-vinyl acetate (VA) copolymer, ethylene-ethyl acrylate (EA) copolymer, ethylene-methacrylate copolymer. Examples include coalescence. The acid-modified polyethylene resin (α) can be used alone or in combination of two or more. In addition, a polyethylene-based resin that is not acid-modified may be blended within a range not departing from the object of the present invention. In addition, Tm (alpha) _{60 in} case resin ((alpha)) is a mixture which consists of a combination of 2 or more resin is a value determined from the DSC melting curve of the said mixture.

Specific examples of the acid-modified polyethylene resin (α) include Admer (trade name) manufactured by Mitsui Chemicals, Adtex (trade name) manufactured by Nippon Polyolefin Co., Ltd., and Polybond (trade name) manufactured by Crompton. And Bond First (trade name) manufactured by Sumitomo Chemical Co., Ltd.

As described above, the crystalline polyethylene resin (β) constituting the layer (A-2) _satisfies Tm _α60 <Tm _β60 , preferably Tm _α60 <Tm _β70 , more preferably Tm _α60 <Tm _β80. Although selected, it is preferable that _Tmβ60 is 115 ° C. or higher from the viewpoint of heat resistance of the resulting multilayer film. More preferably, _Tmβ60 is 120 ° C or higher, and further preferably 125 ° C or higher. The upper limit of Tm _β60 is not particularly limited, but is _actually about 135 ° C. because it is a polyethylene resin.

Examples of the crystalline polyethylene resin (β) include, for example, an ethylene homopolymer and a random copolymer of ethylene and a small amount of a comonomer (eg, 1-butene, 1-hexene, 1-octene, etc.). . Specifically, high-density polyethylene, high-pressure low-density polyethylene, ultra-low-density to high-density linear polyethylene using a metallocene catalyst, ultra-low-density to high-density long-chain branched polyethylene using a Brookhart catalyst, linear And ultra-low density to high density polyethylene. The crystalline polyethylene resin (β) can be used singly or in combination of two or more. In addition, when resin ((beta)) is a mixture which consists of 2 or more types of combinations, temperature, such as Tm (beta) ₆₀ , is a value determined from the DSC melting curve of the said mixture.

Examples of commercially available crystalline polyethylene resins (β) include Evolue SP4530 and Hi-Zex 3300F manufactured by Prime Polymer Co., Ltd., Novatec HD HY560 manufactured by Nippon Polyethylene Co., Ltd., and UBE Super Polyethylene Umerit manufactured by Ube Industries, Ltd. 4040F etc. are mentioned.

Since the crystalline polyethylene resin (β) has thermal adhesiveness, when the resulting multilayer film is processed into a bag shape with the layer (A-2) inside, and the opening of the bag is heat sealed. When sealed, it can be processed well.

The polyolefin-based resin film (A) has one or more layers (A-3) made of the adsorption functional resin composition (γ) between the layers (A-1) and (A-2).

The adsorptive functional resin composition (γ) includes (a) 100 parts by mass of a polyethylene resin, and (b) 5 to 300 parts by mass of the adsorbent functional filler, and the adsorbent functional filler (b) has a particle size of 30 μm or less. (D99) and a particle size (D50) of 20 μm or less. Here, D99 and D50 refer to the particle diameters at points where 99% by mass and 50% by mass are accumulated from the smaller particle diameter in the particle size distribution, respectively.

In the adsorption functional resin composition (γ) according to the present invention, the adsorption functional filler (b) is 1 to 300 parts by mass, preferably 5 to 250 parts by mass, with respect to 100 parts by mass of the polyethylene resin (a). Preferably, it is contained in an amount of 10 to 200 parts by mass. When the blending amount of the adsorption functional filler (b) is less than the above lower limit, a sufficient adsorption function cannot be obtained, and when it exceeds the above upper limit, film forming property and drawing workability may be deteriorated.

(A) Polyethylene resin The polyethylene resin (a) is not particularly limited, and examples thereof include ethylene polymers such as ultra-low density polyethylene, linear low density polyethylene, low density polyethylene, and high density polyethylene, Examples thereof include ethylene-vinyl acetate copolymers, ethylene copolymers such as ethylene-ethyl acrylate, and ethylene-α-olefin copolymer rubber. Examples of the α olefin include propylene, 1-butene, 1-hexene, 1-octene and 1-decane. From the viewpoint of miscibility with the adsorption functional filler (b), the polyethylene resin (a) is preferably a polyethylene resin composition containing (a-1) an ethylene polymer and (a-2) an acid-modified resin. It is a thing.

(A-1) Ethylene-based polymer The ethylene-based polymer has sufficient heat resistance and sufficient filler receptivity to improve the appearance and film thickness stability of the film (A). Thus, it is preferable to satisfy the following (i) to (iv).
(I) The peak top melting point (Tm) on the highest temperature side in the DSC melting curve is 110 ° C. or higher.
(Ii) The heat of fusion (ΔH) in the DSC melting curve is 90 to 180 J / g.
(Iii) The crystallinity at 110 ° C. (Xc (110)) is 10 to 60%, and (iv) MFR (190 ° C., 21.18N) is 0.1 g / 10 min or more and less than 10 g / 10 min. is there.
Regarding the component (a-1), DSC measurement was performed using a DSC Q1000 model of TA Instruments (TA Instruments Japan Co., Ltd.), and the sample was held at 190 ° C. for 5 minutes. The DSC melting curve was obtained by performing a temperature program in which the temperature was cooled to −10 ° C. at a rate of temperature decrease of 10 ° C./min, held at −10 ° C. for 5 minutes, and then heated to 190 ° C. at a temperature increase rate of 10 ° C./min. .

When the peak top melting point (Tm) is lower than 110 ° C., the heat resistance may be insufficient. The peak top melting point (Tm) is preferably 120 ° C. or higher, more preferably 125 ° C. or higher. The upper limit of the peak top melting point (Tm) is not particularly limited, but is actually about 135 ° C. because it is an ethylene polymer.

Further, if the heat of fusion (ΔH) is less than 90 J / g, the heat resistance may be insufficient, and if it exceeds 180 J / g, the filler acceptability may be insufficient and the film forming property may be inferior. The heat of fusion (ΔH) is preferably 100 to 170 J / g.

Further, if the crystallinity (Xc (110)) is less than 10%, the heat resistance may be insufficient, and if it exceeds 60%, the filler acceptability may be insufficient and the film forming property may be inferior. The crystallinity (Xc (110)) is preferably 15 to 45%. The crystallinity at temperature T (Xc (T)) means the ratio of maintaining a crystalline state without melting at temperature T. For example, the crystallinity at 110 ° C. (Xc (110)) is , Calculated as the ratio of the melting enthalpy at 110 ° C. or higher to the total melting enthalpy in the DSC melting curve.

Furthermore, when the MFR is 10 g / 10 min or more, the melt-kneading property (filler dispersibility) between the polyethylene resin composition (a) and the water-absorbing filler (b) becomes insufficient, and the film (A) is formed. The pullability at the time may be reduced, and if it is less than 0.1 g / 10 minutes, it may be difficult to adjust the thickness of the film (A). The MFR is preferably 0.2 to 7 g / 10 min, most preferably 0.5 to 5 g / 10 min.

The ethylene polymer (a-1) is not particularly limited as long as it satisfies the requirements (i) to (iv). For example, low density polyethylene, linear low density polyethylene, ultra low density polyethylene, high density polyethylene, and a copolymer of ethylene and α-olefin (for example, 1-butene, 1-hexene, 1-octene, etc.) can be mentioned. An ethylene copolymer using vinyl acetate, methyl acrylate, ethyl acrylate, or the like as a comonomer has a large decrease in crystallinity due to the comonomer, and thus it is difficult to satisfy the requirements (i) to (iv).

An ethylene-type polymer can be used individually by 1 type or as a mixture which mix | blended 2 or more types arbitrarily. When used as a mixture, the entire mixture may satisfy the above requirements (i) to (iv).

(A-2) Acid-modified resin The acid-modified resin has improved miscibility between the hydrophobic ethylene-based polymer (a-1) and the hydrophilic adsorption functional filler (b). It is a component for accelerating the dispersion of the adsorption functional filler so that the film does not have defects such as blisters when it is formed.

The acid-modified resin used in the present invention may be anything as long as it is a resin modified with an unsaturated carboxylic acid or a derivative thereof. Examples of unsaturated carboxylic acids include, for example, maleic acid, itaconic acid, fumaric acid, and examples of derivatives thereof include, for example, maleic acid monoester, maleic acid diester, maleic anhydride, itaconic acid monoester, Examples include itaconic acid diester, itaconic anhydride, fumaric acid monoester, fumaric acid diester, fumaric anhydride and the like. Examples of the resin include ethylene such as linear polyethylene, ultra-low density polyethylene, high density polyethylene, ethylene-vinyl acetate (VA) copolymer, ethylene-ethyl acrylate (EA) copolymer, and ethylene-methacrylate copolymer. Examples thereof include a polymer, a propylene polymer, and a styrene elastomer. From the viewpoint of miscibility with the ethylene polymer (a-1), the resin is most preferably an ethylene polymer.

The acid-modified resin preferably has an MFR (190 ° C., 21.18 N) of 0.1 to 10 g / 10 min. More preferably, it is 0.2 to 7 g / 10 minutes, and most preferably 0.5 to 5 g / 10 minutes. If the MFR is higher than the above upper limit, the pullability during film formation of the film (A) may be lowered. If the MFR is lower than the lower limit, it may be difficult to adjust the thickness of the film (A).

Specific examples of acid-modified resins include Admer (trade name) manufactured by Mitsui Chemicals, Adtex (trade name) manufactured by Nippon Polyolefin Co., Ltd., Polybond (trade name) manufactured by Crompton, and Sumitomo Chemical Co., Ltd. ) Manufactured Bond First (trade name).

The acid-modified resins can be used alone or in combination of two or more.

The polyethylene resin composition preferably contains 99 to 60% by mass and 1 to 40% by mass of the ethylene polymer (a-1) and the acid-modified resin (a-2), respectively. More preferably, they are 97 to 70% by mass of the ethylene polymer (a-1) and 3 to 30% by mass of the acid-modified resin (a-2), and more preferably 95 to 95% of the ethylene polymer (a-1). 80% by mass and 5 to 20% by mass of the acid-modified resin (a-2). If the acid-modified resin (a-2) is small (that is, the ethylene polymer (a-1) is large), the adsorptive functional filler (b) is not sufficiently dispersed, and the grease is not formed during film formation. In many cases, the film (A) tends to generate defects such as bumps. On the other hand, when the amount of the acid-modified resin (a-2) is large (that is, the amount of the ethylene polymer (a-1) is small), the interaction between the acid-modified resin and the adsorption functional filler becomes very strong, and the adsorption functionality The kneading load during production of the resin composition (γ) and the extrusion load during film production of the film (A) may increase. Moreover, the tensile elongation of the film (A) may decrease.
(B) Adsorption functional filler The adsorption functional filler is a substance having a function of adsorbing and removing substances that inhibit or reduce the performance of lithium ion secondary batteries and electric double layer capacitors. (B) a water adsorbent, (b) a carbon monoxide oxidation catalyst, and (c) a carbon dioxide adsorbent. These can be used alone or in combination of two or more.

It is necessary to use an adsorbing functional filler having a controlled particle size distribution so that a uniform film can be obtained which is well dispersed in a polyethylene resin and has no defects such as bumps. That is, the water-absorbing filler used in the present invention has a particle size (D99) of 30 μm or less and a particle size (D50) of 20 μm or less. D99 is preferably more than 0.01 μm and not more than 20 μm, more preferably more than 0.1 μm and not more than 15 μm. D50 is preferably 0.01 to 15 μm, more preferably 0.1 to 10 μm. A coarse filler having a particle size exceeding the upper limit may become a film defect or foreign matter when it is formed. In addition, fillers with too fine particles aggregate to form defects or foreign matter of the film, or if they do not aggregate, a large amount of air is embraced, resulting in poor melt-kneading workability in the production of the water absorbent resin composition. There is a case to do. In order to control the particle size distribution, there are a method of generating large particles and pulverizing and classifying them, and a method of generating fine particles from the beginning and classifying them. Either method may be used as long as the particle size distribution can be controlled within the above range, and is not particularly limited. However, from the viewpoint of extrusion load and film forming property, a method of generating fine particles from the beginning is more preferable.

(Ii) Examples of the moisture adsorbent include zeolite (for example, molecular sieve 3A, molecular sieve 4A), magnesium sulfate, calcium oxide, strontium oxide, aluminum oxide, silica gel, lime and calcined hydrotalcite.

(B) Examples of the carbon monoxide oxidation catalyst include hopcalite and supported noble metal catalyst soot.

(C) Examples of the carbon dioxide adsorbent include strontium oxide, calcium oxide, zeolite having a pore diameter of 0.4 nm or more (for example, molecular sieve 4A, molecular sieve 5A), and magnesium oxide having a BET specific surface area of 50 m ² / g or more. Can be mentioned.

In addition to the above components, the adsorptive functional resin composition (γ) includes a slip agent, phosphorus-based, phenol-based, sulfur-based antioxidant, anti-aging agent, light stabilizer, ultraviolet absorber, as necessary. Weathering agent such as copper damage prevention agent, nucleating agent such as aromatic phosphate metal salt and gelol, antistatic agent such as glycerin fatty acid monoester, coloring agent, fragrance, antibacterial agent, zinc oxide, calcium carbonate Additives such as plasticizers such as fillers such as talc and metal hydrate, glycerin fatty acid ester-based, paraffin oil, phthalic acid-based, ester-based and the like may be included.

The slip agent can improve the melt-kneading workability during the production of the adsorptive functional resin composition (γ), and can avoid the occurrence of dies and greases during film formation. Examples of the slip agent include metal soaps such as calcium stearate, fatty acid amides such as oleic acid amide and erucic acid amide, polyethylene wax, silicone gum, and silicone oil. The addition amount of the slip agent is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the polyethylene resin (a).

The adsorption functional resin composition (γ) can be obtained by melting and kneading necessary components. The melt-kneading can be performed using a conventional apparatus such as a twin screw extruder or a Banbury mixer. The kneading temperature is preferably higher than the molding temperature in order to avoid moisture absorption foaming troubles during molding.

The polyolefin resin film (A) is obtained by co-extrusion of an acid-modified polyolefin resin (α), a crystalline polyethylene polymer (β), and an adsorption functional resin composition (γ) by a T-die method or an inflation method. It can be obtained by forming a film with a desired thickness.

For the thickness of the polyolefin-based resin film (A), a range suitable for the exterior of a lithium ion secondary battery or an electric double layer capacitor is selected. Therefore, although it is not limited to the following range, it is usually 30 to 150 μm, particularly 40 to 100 μm.

The thickness of each layer of the polyolefin-based resin film (A) and the thickness ratio of (A-1) / (A-3) / (A-2) depend on the manufacturability of the film (A), desired heat laminating properties, heat sealing Selected in consideration of properties and adsorption functionality. Accordingly, although not limited to the following range, in general, the thickness of the layer (A-1) is preferably 3 μm or more, more preferably 5 μm or more in order to obtain a stable thermal laminate strength. Further, the thickness of the layer (A-2) is preferably 3 μm or more in order to obtain a stable heat seal strength, more preferably 5 μm or more, but it is thin from the viewpoint of the adsorption function of the layer (A-3). Is preferred. Furthermore, from the viewpoint of manufacturability of the polyolefin resin film (A), it is better that these layers do not have an extreme thickness difference. Therefore, for example, when the total thickness of the film (A) is 80 μm, the thickness ratio of (A-1) / (A-3) / (A-2) is 10/60/10, 10/65/5. And 20/50/10.

The film (A) thus obtained can then be used to obtain the composite multilayer film of the present invention by laminating the layer (B) on the layer (A-1) and further laminating the layer (C). Since the film (A) has the layer (A-1) on one side of the adsorption functional layer (A-3) and the layer (A-2) on the other side, the layer (B) And the problem that the adsorption function of the composite multilayer film is lowered due to unnecessary adsorption of the layer (A-3) during the lamination of (C) is small.

(B) Aluminum layer at least one surface of which is subjected to chemical conversion treatment Various methods of chemical conversion treatment of aluminum are known, such as adhesion strength between the polyolefin resin film (A) and the aluminum layer (B), and an anti-electrolytic solution. Any method may be used as long as the property is sufficient. In view of environmental load, non-hexavalent chromium conversion treatment is preferable, and non-chromium conversion treatment is more preferable. Non-chromium chemical conversion treatment is a chemical conversion treatment that does not use chromium, and includes hydrothermal treatment (boehmite treatment) and chemicals that do not contain chromium, such as phosphates such as zinc phosphate and manganese phosphate, and organic substances. Chemical conversion treatment using an acid metal salt (such as iron salt, zinc salt, manganese salt, copper salt, nickel salt, cobalt salt, vanadium salt, scandium salt of carboxylic acid such as oxalic acid or acetic acid) is included. The layer (B) in the present invention can be obtained by subjecting an untreated aluminum foil to the above treatment.

(C) Polyamide layer Polyamide is excellent in mechanical strength, and by having this layer, durability of the resulting multilayer film can be enhanced. The polyamide used is not particularly limited. For example, nylon 6, nylon 11, nylon 12, nylon 66, nylon 610, nylon 6T, nylon 6I, nylon 9T, nylon M5T, nylon nylon 612, Kevlar (trademark of Kevlar, DuPont) ), Nomex (trademark of DuPont).

Examples of commercially available polyamides include UBE nylon (nylon 6), UBE nylon 66 (nylon 66), UBESTA (nylon 12) manufactured by Ube Industries, Ltd., and alamin (nylon 6, 66, 610, etc.) manufactured by Toray Industries, Inc. ), Toyobo nylon manufactured by Toyobo Co., Ltd. (nylon 6, 66, 6T, etc.), Novamid manufactured by Mitsubishi Engineering Plastics Co., Ltd. (nylon 6, 66, 12), Unitika nylon 6, manufactured by Unitika Ltd., Unitika nylon 66 and Leona (nylon 66) manufactured by Asahi Kasei Chemicals Corporation are listed.

From the viewpoint of mechanical strength, a biaxially stretched polyamide film can be particularly preferably used as the layer (C). Commercially available examples include Unitika Corporation's emblem (trade name) and Toray Industries, Inc. Mikutron (trade name).

(D) Polyester resin layer This layer is a protective layer optionally laminated on the layer (C). The layer (C) has good mechanical strength, but is very brittle with respect to a liquid having high permeability and solubility such as an electrolyte used in a lithium ion secondary battery or an electric double layer capacitor. When the multilayer film comprising the above (A) to (C) is made into a packaging bag so that the layer (C) is the outermost layer, and the contents such as the electricity storage element and the electrolyte solution are put therein, and the bag mouth is heat sealed. In addition, the contents may spill. Therefore, it is advantageous to have a further layer (D) on top of the layer (C).

The polyester resin constituting the layer (D) is not particularly limited, and examples thereof include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polytrimethylene terephthalate (PTT), and polybutylene naphthalate. Includes phthalate (PBN).

Examples of commercially available polyester resins include Viropet (PET and PBT) manufactured by Toyobo Co., Ltd., Toraycon (PBT) manufactured by Toray Industries, Inc., Novaduran (PBT) manufactured by Mitsubishi Engineering Plastics Co., Ltd., and Unitika Co., Ltd. ), And Teijin Chemicals' PET resin, Teonex (PEN) and PBN resin.

Further, from the viewpoint of mechanical strength and solvent resistance, a biaxially stretched polyester film can be particularly suitably used as the layer (D). Commercial examples include Lumirror (trade name) from Toray Industries, Inc., Toyobo Ester Film (trade name) from Toyobo Co., Ltd., and Emblet (trade name) from Unitika Corporation.

The composite multilayer film of the present invention includes: 1) a step of laminating an aluminum layer (B) having a chemical conversion treatment on at least one side thereof on one side of the polyolefin resin film (A); and 2) a polyamide on the layer (B). It can manufacture by the method including the process of laminating | stacking the layer (C). Here, the film (A) comprises an acid-modified polyethylene resin (α) layer (A-1), a crystalline polyethylene resin (β) layer (A-2), and one or more layers positioned therebetween. The temperature at which the acid-modified polyethylene resin (α) has a crystallinity of 60% is Tm _α60 , and the crystallinity of the crystalline polyethylene resin (β) is 60%. when the composed temperature was Tm _Beta60, a _{_Tm} α60 <Tm β60, the step 1) is by heat lamination at a temperature _{(T R)} satisfying the following (1), a layer on the layer (a-1) The surface subjected to the chemical conversion treatment of (B) is performed so as to be laminated.
Xc (T _R ) <60% of α and Xc (T _R ) ≧ 60% of β (1)
Here, Xc _{(T R)} is crystallinity at a temperature _{T R.}

The heat lamination, the above range of temperatures to satisfy (1) (heat roll temperature T _R), can be carried out by conventional methods. Preferably, it is carried out at a temperature such that Xc (T _R ) of α <50%, more preferably <40%, and Xc (T _R ) of β ≧ 70%, more preferably ≧ 80%. At a temperature higher than the above range (temperature range where Xc (T _R ) of β <60%), the polyolefin film (A) may be fused to the hot roll and cannot be laminated, and a temperature lower than the above range (of α In the temperature range where Xc (T _R ) ≧ 60%), the adhesive strength between the film (A) and the layer (B) may be insufficient.

Step 2) can be performed by adhering the layer (B) side of the film obtained in step 1) and the polyamide layer (C) by a dry laminating method. As the adhesive, an ordinary two-pack type of a polyol main agent and an isocyanate curing agent can be used. Specifically, Takelac (polyol-based main agent) / Takenate (isocyanate-based curing agent) two-component type manufactured by Mitsui Chemicals Polyurethane Co., Ltd. can be mentioned.

In the composite multilayer film further having the layer (D) on the layer (C), the layer (D) is dried on the layer (C) of the film obtained in the above step 2) in the same manner as in the above step 2). It can be obtained by bonding by a laminating method. The same adhesive can be used as in step 2) above.

In the composite multilayer film of the present invention thus obtained, the polyolefin resin film layer and the surface-treated aluminum layer are directly bonded with sufficient adhesive strength without applying an anchor coating agent or an adhesive, In addition, it has excellent low-temperature resistance and also has an adsorption function for moisture, carbon monoxide, carbon dioxide, etc., so that it can encapsulate lithium ion secondary batteries and electric double layer capacitor storage elements for hybrid and electric vehicles. It can be particularly suitably applied as an exterior material.

EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to a following example.

Examples 1 to 9 and Comparative Examples 1 to 5
(1) Production of adsorptive functional resin composition (γ ) The components (parts by mass) shown in Table 1 were dry blended, and this was mixed with a twin-screw extruder TEX28 of Nippon Steel Co., Ltd. By melt-kneading, pellets of the resin composition (γ) for the layer (A-3) were obtained. The resin temperature at the exit of the twin screw extruder was 240 ° C. (using a vacuum vent).

(2) Production of polyolefin film (A) Acid-modified polyethylene-based polyolefin resin (α) for layer (A-1) shown in Table 1 and crystalline polyethylene propylene for layer (A-2) Layer (A-1) / layer (by using a multi-manifold type multi-layer coextrusion T-die using the resin-based resin polymer (β) and the adsorption functional resin composition (γ) obtained in (1) above. A-3) / Layer (A-2) A film (A) having a thickness ratio of 10/65/5 and a total thickness of 80 μm was produced. The T-die outlet resin temperature was 250 ° C. and the take-up speed was 20 m / min. The layer (A-1) was subjected to corona treatment so that the wetting index was 45 mN / m or more.

(3) Boehmite treatment of aluminum foil Untreated aluminum foil (super foil, JIS number A-8079, thickness 40 μm) manufactured by Toyo Aluminum Co., Ltd. was fed into a water bath and immersed in boiling water for 5 minutes. The operation of winding the dipped portion was performed over the entire length of the aluminum foil to obtain an aluminum foil (B) having both surfaces treated with boehmite.

(4) Thermal lamination of polyolefin film (A) and aluminum foil (B) The polyolefin film (A) obtained above and the aluminum foil (B) treated with boehmite are mixed with dielectric heat generated by Tokuden Corporation. Using a laminator JD-DW, thermal lamination was performed so that the polyolefin film layer (A-1) was in contact with the aluminum foil. The temperature of the hot roll was set to the heat laminating operation temperature shown in Table 1, the pressure was 0.3 MPa, and the take-up speed was 2 m / min.

(5) Dry lamination of polyamide film (C) On the aluminum foil of the film obtained by the above thermal lamination, a nylon film (emblem ONUM, thickness 15 μm) of Unitika Co., Ltd. is used as a plain metal test laminator. Dry lamination was performed using MODEL200. A two-pack type of Takelac A-1143 / Takenate A-3 (9/1 mass ratio) manufactured by Mitsui Chemicals Polyurethane Co., Ltd. was used as an adhesive, and this was diluted with ethyl acetate so as to have a solid content of 40 mass%. The thing was apply | coated so that it might become a coating amount of 4.5 g / m < ² >. After lamination, curing was performed at 70 ° C. for 48 hours.

The composite multilayer film obtained above was subjected to the following test. The results are shown in Table 2.

(1) Thermal laminating properties Cut 10 rows x 10 rows in a grid pattern at intervals of 1 mm both vertically and horizontally on a polyolefin film (A) of a composite multi-layer film, and then adhesive tape is applied from above and adhesive is immediately applied. The tape was peeled off. A case where the film was peeled off without adhering to the adhesive tape was marked with ◯, and the other case was marked with x.

(2) Electrolytic solution resistance-1
A composite multilayer film having a size of 20 mm × 100 mm is mixed with ethylene carbonate, dimethyl carbonate and diethyl carbonate in a volume ratio of 1: 1: 1, and lithium hexafluorophosphate is dissolved in this mixture so as to be 1 mol / L. The film was immersed in the electrolyte solution (manufactured by Kishida Chemical Co., Ltd.) and subjected to an accelerated deterioration test at 80 ° C. × 168 hours to examine whether or not the laminate was peeled off. A sample that did not peel off and that could not be peeled off using tweezers was marked with ◯, and the others were marked with ×.

(3) Heat seal strength Toyo Co., Ltd. with the polyolefin film (A) layer (A-2) of the composite multilayer film so that the machine direction of the film is the tensile direction of the T-peel test Using an HG-100 heat seal tester manufactured by Seiki Seisakusho, fusion was performed under conditions of a temperature of 170 ° C., a time of 2 seconds, and a pressure of 0.3 Pa. Next, a T-shaped peel test was performed using an AE-CT type tensile tester manufactured by Toyo Seiki Seisakusho Co., Ltd. (peel width 25 mm, peel rate 100 mm / min, peel angle 180 °), and layer (A- 2) The heat seal strength between each other was measured.

(4) Drawing workability Using a composite multilayer film, a mold having a recess size of 70 mm long x 70 mm wide x 4 mm deep and a press machine (laminate film forming tester, manufactured by Hosen Co., Ltd.) Then, drawing was performed under the conditions of a pressing force of 5 MPs and a pressing speed of 1 s / 100 mm so that the polyolefin film (A) side was concave. Two composite multilayer films that have been drawn are overlapped so that the respective polyolefin film (A) layers face each other, and any three sides are 5 mm wide and heat sealed under conditions of 170 ° C., 1 MPa, and 2 seconds. Processed into a bag. The drawn and heat-sealed parts were observed visually and with a stereomicroscope to check for laminate peeling. The case where there was no peeling was marked with ◯, and the others were marked with ×.

(5) Electrolytic solution resistance-2
36 ml of an electrolytic solution (manufactured by Kishida Chemical Co., Ltd.) in which ethylene carbonate, dimethyl carbonate and diethyl carbonate were mixed at a volume ratio of 1: 1: 1 and lithium hexafluorophosphate was dissolved to 1 mol / L. The test piece (4) was poured from the opening of the bag, and the opening was heat-sealed under conditions of 170 ° C., 1 MPa, 2 seconds with a width of 5 mm to obtain a test piece. This test piece was subjected to an accelerated deterioration test for 100 days using an environmental testing machine set at a temperature of 30 ° C. and a humidity of 95%. Similarly, using an environmental tester set at a temperature of 80 ° C. and a humidity of 95%, it was subjected to an accelerated deterioration test for 100 days. In both tests, the presence or absence of abnormalities such as liquid leakage was examined and evaluated according to the following criteria.
○: There was no abnormality in either test.
(Triangle | delta): Although there was no abnormality in the test at 30 degreeC, abnormality was recognized in the test at 80 degreeC.
X: Abnormality was observed in both tests.

(6) Low temperature resistance After the test piece prepared in the above test (5) was conditioned for 24 hours in an environment of -40 ° C, a bag was placed from a height of 1 m onto a stainless steel bat. A drop test was conducted to drop 100 times in the standing direction. At this time, the falling direction of the bag was made constant, and the location where it landed on the stainless steel pad was made the same every time. After the drop test, the test piece was returned to room temperature and checked for bag breakage and liquid leakage. The case where there was no bag breakage and liquid leakage was marked with ◯, and the case where bag breakage or liquid leakage was observed was marked with ×.

(7) Heat resistance The test piece prepared in the above test (5) was boiled in boiling water for 5 minutes. The case where there was no bag breakage and liquid leakage was marked with ◯, and the case where bag breakage or liquid leakage was observed was marked with ×.

(8) Water absorption capacity Ethylene carbonate, dimethyl carbonate and diethyl carbonate were mixed at a volume ratio of 1: 1: 1, and a very small amount of water was mixed therewith to obtain a test solution. The amount of water in this test solution was measured with a Karl Fischer volumetric titrator (AQ-300 from Hiranuma Sangyo Co., Ltd.) (initial water content). 20 g of this test solution was injected from the opening of the bag obtained in the above test (4), and the opening was heat-sealed under conditions of 170 mm, 1 MPa, and 2 seconds with a width of 5 mm. After storing at 25 ° C. for 48 hours, the bag was opened and the water content in the test solution was measured in the same manner (residual water content).

(9) Concentration change of carbon monoxide and carbon dioxide in a nitrogen / carbon monoxide mixed gas Ten composite multilayer films of 10 cm x 10 cm were placed in a tetra bag and filled with 255 mL of nitrogen. 45 mL of carbon monoxide was injected here (calculated concentration of carbon monoxide: 15 vol%). This was left for 24 hours at room temperature and normal pressure, and then the carbon monoxide concentration and the carbon dioxide concentration were measured by a gas chromatograph. In addition, since gas permeate | transmits and escapes little by little from a tetra bag, when the measurement of a blank (when the said film is not used) was also performed simultaneously, the carbon monoxide density | concentration after 24 hours is 14.1 vol%, Carbon was not detected.

(10) Concentration change of carbon dioxide in nitrogen / carbon dioxide mixed gas Since carbon dioxide has high permeability, the carbon dioxide adsorption ability by the film was measured. In the test (9), the carbon dioxide concentration was measured in the same manner as in the test (9) except that 45 mL of carbon dioxide was injected instead of injecting 45 mL of carbon monoxide. The carbon dioxide concentration in the blank was 12.3 vol%.

The materials used are as follows.
NF539: Admer NF539 (trade name) manufactured by Mitsui Chemicals, maleic anhydride-modified polyethylene, temperature at which Xc = 60%: 93 ° C., peak top melting point (Tm) on the highest temperature side in the DSC melting curve = 121 ℃
NE827: Admer NE827 (trade name) manufactured by Mitsui Chemicals, maleic anhydride-modified polyethylene, temperature at which Xc = 60%: 89 ° C., Tm = 124 ° C.
XE070: Admer XE070 (trade name) manufactured by Mitsui Chemicals, maleic anhydride-modified polyethylene, temperature at which Xc = 60%: 54 ° C., Tm = 84 ° C.
NE065: Admer NE065 (trade name) manufactured by Mitsui Chemicals, maleic anhydride-modified polyethylene, temperature at which Xc = 60%: 111 ° C., Tm = 123 ° C.
SP4530: Evolue SP4530 (trade name) manufactured by Prime Polymer Co., Ltd., linear high-density polyethylene by metallocene catalyst, temperature at which Xc = 60%: 126 ° C., temperature at which Xc = 70%: 121 ° C., Xc = 80% Temperature: 110 ° C., Tm = 132 ° C., Density: 942 Kg / m ³
SP2520: Evolue SP2520 (trade name) manufactured by Prime Polymer Co., Ltd., linear low density polyethylene by metallocene catalyst, temperature at which Xc = 60%: 98 ° C., temperature at which Xc = 70%: 91 ° C., Xc = 80% Temperature: 98 ° C., Tm = 121 ° C., Density: 928 Kg / m ³
KF271: Kernel KF271 (trade name) manufactured by Nippon Polyethylene Co., Ltd., linear low density polyethylene with metallocene catalyst, MFR (190 ° C., 21.18 N) = 2.4 g / 10 min, density 913 kg / m ³ , Tm = 127 ° C., ΔH = 127 J / g, Xc110 = 26%
Molecular sieve 4A LPH: Synthetic zeolite with a pore diameter of 0.4 nm manufactured by Tosoh Corporation, D99 = 20 μm, D50 = 12 μm
Copper zeolite: manufactured by Tosoh Corporation, D99 = 20 μm, D50 = 12 μm
Hopcalite: A pulverized and classified composite metal oxide catalyst (CuMn ₂ O ₄ ) manufactured by GL Sciences, D99 = 12 μm, D50 = 3 μm
5% Pd—MgO-01: Magnesium oxide-supported palladium catalyst manufactured by N.E. Chemcat Co., Ltd., 5 mass%, D99 = 6 μm, D50 = 2 μm
STO: Strontium oxide classified by Sakai Chemical Industry Co., Ltd., D99 = 18 μm, D50 = 5 μm
Starmag PSF-150F: High BET magnesium oxide manufactured by Kamishima Chemical Industry Co., Ltd., BET specific surface area = 150 m ² / g, D99 = 3 μm, D50 = 1 μm
Anhydrous magnesium sulfate: manufactured by Maui Chemical Industry Co., Ltd., D99 = 118 μm, D50 = 24 μm
LBT-77: Sakai Chemical Industry Co., Ltd., polyethylene wax calcium stearate

For KF271, the DSC measurement was held at 190 ° C. for 5 minutes, then cooled to −10 ° C. at a rate of temperature decrease of 10 ° C./minute, held at −10 ° C. for 5 minutes, and then 10 ° C./minute. This was performed using a temperature program of heating to 190 ° C. at a rate of temperature increase.

As is apparent from Table 2, the composite multilayer films of the present invention of Examples 1 to 9 are excellent in heat laminating property, heat seal strength, electrolytic solution resistance, drawing workability, low temperature resistance and heat resistance, and moisture. And has the function of adsorbing carbon monoxide.

On the other hand, the composite multilayer film of Comparative Example 1 in which the content of the filler (b) in the resin composition (γ) is less than the lower limit of the present invention did not exhibit an adsorption function. The composite multilayer film of Comparative Example 2 in which the content of the filler (b) exceeded the upper limit of the present invention was inferior in drawability, and the tests (5) to (10) could not be performed. In Comparative Example 3 in which a filler (b) having a coarse particle size was used, the adhesive strength between the film (A) and the aluminum foil (B) was not sufficient, and the heat seal strength and the drawability were not sufficient. Therefore, tests (5) to (10) could not be performed.

Comparative Example 4 is an example in which NE065 is used instead of NE827 as the resin (α) in Example 8, and the resin (α) and the resin (β) do not satisfy the relationship of Tm _α60 <Tm _β60 . When heat lamination was performed at a temperature (98 ° C.) at which the degree of crystallinity of the resin (β) was 60% or more, lamination was possible, but the adhesive strength was not sufficient. Further, since the heat seal strength and drawability were not sufficient, the above tests (5) to (10) could not be performed. At the temperature (111 ° C.) at which the degree of crystallinity of the resin (α) is 60%, the polyolefin film (A) does not peel off due to adhesion to the hot roll, and cannot be laminated on the aluminum foil (B). .

Comparative Example 5 is an example in which the heat laminating temperature is changed in Example 7, and is a comparative example related to the manufacturing method. When heat lamination was performed at a lower temperature (105 ° C.) where the crystallinity of the resin (α) was 60% or more, lamination was possible, but the adhesive strength was not sufficient. Further, since the heat seal strength and drawability were not sufficient, the above tests (5) to (10) could not be performed. Further, at a higher temperature (130 ° C.) where the crystallinity of the resin (β) is less than 60%, the polyolefin film (A) does not adhere to the hot roll and does not peel off, and is laminated on the aluminum foil (B). I couldn't.

A Polyolefin resin film B Chemical conversion treated aluminum layer C Polyamide layer D Polyester resin layer A-1 Acid-modified polyethylene resin (α) layer A-3 Adsorption functional resin composition (γ) layer A-2 Crystalline polyethylene resin (β) layer

Claims

At least one surface of the aluminum layer (B) subjected to chemical conversion treatment has a polyolefin resin film (A) on one surface and the chemical conversion treatment surface, and a polyamide layer (C) on the other surface. In the composite multilayer film having the film (A), the layer (A-1) of the acid-modified polyethylene resin (α), the layer (A-2) of the crystalline polyethylene resin (β), and a position therebetween The temperature at which the acid-modified polyethylene resin (α) has a crystallinity of 60% is defined as Tm α60 , and the crystalline polyethylene resin (β) is crystallized. when degree is the temperature at which 60% was Tm β60, a Tm α60 <Tm β60, the layer (B) is laminated directly on the layer (a-1), a layer (a-3),
It consists of an adsorption functional resin composition (γ) containing (a) 100 parts by mass of a polyethylene-based resin and (b) 1 to 300 parts by mass of an adsorption functional filler. Particle diameter (D99) and particle diameter (D50) of 20 μm or less, wherein D99 and D50 are respectively the particle diameters at the points where 99% by mass and 50% by mass are accumulated from the smaller particle diameter in the particle size distribution. Say, where composite multilayer film.
The composite multilayer film according to claim 1, wherein the chemical conversion treatment is a non-chromium chemical conversion treatment.
The adsorption functional filler (b) is one or more selected from the group consisting of (a) a moisture adsorbent, (b) a carbon monoxide oxidation catalyst, and (c) a carbon dioxide adsorbent. A composite multilayer film as described in 1.
(I) The moisture adsorbent is
The composite multilayer film according to claim 3, which is at least one selected from the group consisting of zeolite, molecular sieve, magnesium sulfate, calcium oxide, strontium oxide, aluminum oxide, silica gel, lime and calcined hydrotalcite.
(B) The composite multilayer film according to claim 3 or 4, wherein the carbon monoxide oxidation catalyst is one or more selected from the group consisting of hopcalite and a supported noble metal catalyst.
(C) The carbon dioxide adsorbent is one or more selected from the group consisting of strontium oxide, calcium oxide, zeolite having a pore diameter of 0.4 nm or more, and magnesium oxide having a BET specific surface area of 50 m 2 / g or more. The composite multilayer film according to any one of claims 3 to 5.
(A) Polyethylene resin
(A-1) 99 to 60% by mass of an ethylene polymer having the following characteristics (i) to (iv)
(I) The peak top melting point (Tm) on the highest temperature side in the DSC melting curve is 110 ° C. or higher.
(Ii) The heat of fusion (ΔH) in the DSC melting curve is 90 to 180 J / g.
(Iii) The crystallinity at 110 ° C. (Xc (110)) is 10 to 60%, and (iv) MFR (190 ° C., 21.18N) is 0.1 g / 10 min or more and less than 10 g / 10 min. is there,
And (a-2) acid-modified resin 1 to 40% by mass
7. The polyethylene resin composition comprising: wherein the total amount of component (a-1) and component (a-2) is 100% by mass. Composite multilayer film.
The composite multilayer film according to any one of claims 1 to 7, wherein Tm β60 is 115 ° C or higher.
The composite multilayer film according to any one of claims 1 to 8, wherein Tm α60 is 80 ° C or higher.
The composite multilayer film according to any one of claims 1 to 9, further comprising a polyester resin layer (D) on the layer (C).
A molded article comprising the composite multilayer film according to any one of claims 1 to 10.
The molded body according to claim 11, which is an exterior material for a secondary battery.
The molded body according to claim 11, which is an exterior material of an electric double layer capacitor.
1) a step of laminating a chemically treated aluminum layer (B) on one side of the polyolefin resin film (A), and 2) a step of laminating a polyamide layer (C) on the layer (B). Wherein the film (A) is a layer (A-1) of the acid-modified polyethylene resin (α), a layer (A-2) of the crystalline polyethylene resin (β), and 1 positioned therebetween. The temperature at which the crystallinity of the acid-modified polyethylene resin (α) is 60% is Tm α60 , and the crystallinity of the crystalline polyethylene resin (β) is Tm α60 <Tm β60 , where Tm β60 is the temperature at which 60% is reached , and the above step 1) is performed by thermal lamination at a temperature (T R ) that satisfies the following (1). It is performed so that the surface subjected to the chemical conversion treatment of the layer (B) is laminated thereon Preparation of composite multilayer film of claim 1, wherein,
Xc (T R ) of α <60% and Xc (T R ) of β ≧ 60% (1)
Here, Xc (T R) is crystallinity at a temperature T R.