TWI712201B - Laminate for battery packages, battery package, method for producing battery package, and battery - Google Patents

Abstract

The present invention provides a laminate for battery packages, which has various excellent characteristics. When using the laminate for battery packages to manufacture battery packages, the operating efficiency and yield are good. The laminate for battery packages provided by the present invention is at least sequentially formed from a sealant layer (11), a first adhesive agent layer (12), a barrier layer (14), and a substrate layer (15), and is characterized by that the sealant layer (11) is composed of blocked polypropylene, random polypropylene, and olefinic elastomer. The content ratios in the mass ratio of the blocked polypropylene, random polypropylene, and olefinic elastomer are A, B, and C in sequence. When the melting points of blocked polypropylene, random polypropylene, and olefinic elastomer are mp (A), mp (B), and mp (C) in sequence, the sealant layer (11) meets the following relationships (1)~(4): A > B (1); A > C (2); A+B+C=100 (3); mp (A) > mp (B) ≧ mp (C) (4).

Description

Laminated body for battery exterior, battery exterior body, manufacturing method of battery exterior body, and battery Pool

The present invention relates to a good laminate for battery exterior packaging as a secondary battery or capacitor, etc., a battery exterior body obtained by using the laminate, a method for preparing the battery exterior body, and the battery provided The battery of the exterior body.

While people are raising awareness of the environment and using natural energy sources such as sunlight and wind, they are attracting attention as storage batteries for electric energy, secondary batteries such as lithium-ion batteries, and capacitors such as electric double-layer capacitors.

For the purpose of miniaturization and weight reduction, as an exterior body for these batteries, a laminate for battery exterior in which a metal foil and a resin layer are laminated can be used. Such a laminate for battery exterior packaging is molded into a disc shape having a recessed portion by drawing or the like, and this is used as the exterior container main body. In addition, in the same manner as the main body of the exterior body container, the laminate for battery exterior was molded to obtain the exterior body cover. After accommodating the battery body in the recess of the outer body container body, the outer body cover is overlapped so as to cover the stored battery body, and the edge portion between the container body and the outer body cover is bonded to obtain the The battery of the battery main body is housed in the body.

For the adhesion of the edge portion between the outer packaging body container main body and the outer packaging body cover as described above, simple heat-melting connection (heat sealing) is widely used. Therefore, the outermost layer (innermost layer) of the laminate for battery exterior is usually provided with a heat-sealable sealant layer.

For example, Patent Document 1 discloses a battery packaging material, which is composed of a laminate composed of at least a substrate layer, an adhesive layer 1, a separator layer, an adhesive layer 2, and a sealant layer, and is characterized by , Use a specific adhesive resin composition. In Patent Document 1, by using a homopolypropylene layer as the outermost layer of the sealant layer (the innermost layer of the entire packaging material), a battery packaging material that can be thermally fused at a normal heat sealing temperature is obtained.

Prior art literature

Patent literature

Patent Document 1: Japanese Patent Application Publication No. 2015-109287

In recent years, as the application fields of batteries such as secondary batteries have been expanded, excellent properties such as heat resistance and cold resistance are also required for battery exterior bodies. In addition, with the recent expansion of battery demand, an increase in battery production is required, and a battery exterior body capable of improving the production efficiency and yield when manufacturing batteries is required.

However, as described in Patent Document 1, in the laminate for battery exterior bodies having a sealant layer composed of a homopolypropylene layer as the outermost layer, the heat resistance and cold resistance are insufficient, and the battery is not sufficiently resistant to heat and cold. There is still room for improvement in the production efficiency and yield when the laminate is used for the exterior body to prepare a battery.

The present invention was completed in view of the above-mentioned current situation, and its purpose is to provide Provided is a laminate for battery exteriors with excellent various characteristics, which can improve the work efficiency and yield when manufacturing battery exteriors using the laminate for battery exteriors.

The inventors of the present invention have conducted repeated studies in order to achieve the above object. As a result, they have found that the use of block polypropylene, random polypropylene, and olefin elastomers with melting points that fully satisfy the specific relationship in a specific ratio can improve the battery The heat resistance and cold resistance of the laminate for exterior packaging itself; and when the laminate for battery exterior packaging is used to prepare a battery exterior packaging body, it can be thermally welded at a relatively low temperature.

That is, the present invention adopts the following structure.

The laminate for battery exterior packaging according to the first aspect of the present invention is formed by having at least a sealant layer, a first adhesive layer, a separator layer composed of a metal foil, and a substrate layer in this order, and is characterized in The sealant layer is composed of block polypropylene, random polypropylene, and olefin elastomer, and the content ratios of block polypropylene, random polypropylene, and olefin elastomer in terms of mass ratio are A, B, C, and the melting points of block polypropylene, random polypropylene, and olefin elastomer are respectively mp(A), mp(B), mp(C), the sealant layer satisfies the following formula (1 )~(4) relationship: A>B (1)

A>C (2)

A+B+C=100 (3)

mp(A)>mp(B)≧mp(C) (4)

In the sealant layer, it is preferable that the content of block polypropylene is 35 to 80% by mass, and the content of random polypropylene is 10 to 45% by mass. The content of the body is 10-40% by mass.

Preferably, a second sealant layer is further provided between the sealant layer and the first adhesive layer.

The first adhesive layer preferably contains maleic acid-modified polypropylene and a compound having an epoxy group or an oxazoline group.

The compound having an epoxy group is preferably a Phenol novolac type epoxy resin or an epoxy group-containing polyolefin resin.

The compound having an oxazoline group is preferably an oxazoline group-containing styrene resin.

A battery exterior body according to a second aspect of the present invention, which has the laminate for battery exterior of the first aspect, is characterized by having an internal space for accommodating the battery, and a sealant layer of the laminate for battery exterior The side of is the side of the internal space.

A method for manufacturing a battery exterior body according to a third aspect of the present invention is characterized by comprising: a molding step including: pressing from the sealant layer side of the battery exterior laminate The laminated body for battery exterior packaging of one aspect is the first member of the forming material to form a container body having a recessed portion; an assembling step including: making the sealant layer of the container body and the The laminate for battery exterior is the sealant layer of the second member of the forming material, which is combined in a superposed manner; the joining step includes: thermally fusing the superimposed sealant layers, In order to join one sealant layer and another sealant layer, the temperature during the hot-melt connection is lower than the mp (A) and higher than the mp (B).

The method for producing a battery exterior body according to a fourth aspect of the present invention is characterized by comprising: a molding step including: removing the laminate from the battery exterior body The sealant layer side presses the laminated body for battery exterior packaging of the first aspect as a part of the material forming part to form a molding step of forming a recess; an assembling step, which includes: The area folds the member toward the sealant layer side, and sets the sealant layer on the periphery of the recessed portion in the first area on the recessed portion side with respect to the formed fold line, and relative to the folded The line is overlapped with the sealant layer in the second region on the opposite side of the recess; and a joining step including: thermally fusing the overlapped sealant layers to connect one sealant layer Join with another sealant layer.

A battery according to a fifth aspect of the present invention is characterized by having the battery exterior body of the second aspect.

According to the present invention, it is possible to provide a laminate for battery exteriors with excellent heat resistance and cold resistance, etc., which can improve production efficiency and finished products when using the laminate for battery exteriors to prepare battery exteriors or batteries rate.

10, 50‧‧‧Laminated body

11‧‧‧Sealant layer

11’‧‧‧Second sealant layer

12‧‧‧The first adhesive layer

13‧‧‧The first anti-corrosion layer

14‧‧‧Isolation layer (metal foil)

15‧‧‧Second anti-corrosion layer

16‧‧‧Second Adhesive Layer

17‧‧‧Substrate layer

20‧‧‧Battery exterior body

27‧‧‧Lithium-ion battery

28‧‧‧Mark

29, 34‧‧‧Perimeter

30‧‧‧Container body

31, 51‧‧‧Concavity

32、54‧‧‧peripheral part

33‧‧‧Cover

40、60‧‧‧Secondary battery

52‧‧‧Around

55‧‧‧Forming body

551‧‧‧First area

552‧‧‧Second District

L‧‧‧folding line

Fig. 1 is a schematic cross-sectional view showing the first embodiment of the laminate for battery exterior packaging of the present invention.

Fig. 2 is a perspective view showing an example of a secondary battery manufactured using the laminate for battery exterior packaging of the present invention.

Fig. 3 is a perspective view showing a process of preparing a secondary battery using the laminate for battery exterior packaging of the present invention.

Fig. 4 is a perspective view showing a process of preparing a secondary battery using the laminate for battery exterior packaging of the present invention.

Hereinafter, the present invention will be described based on suitable embodiments.

〔Laminated body for battery exterior〕

The laminate for battery exterior packaging according to the first aspect of the present invention (hereinafter sometimes referred to as "laminate") has at least a sealant layer, a first adhesive layer, a separator layer made of metal foil, and A laminate for battery exterior packaging with a substrate layer.

Fig. 1 is a schematic cross-sectional view showing the structure of a laminate 10 for battery exterior packaging according to an embodiment of the present invention.

The laminated body 10 of this embodiment has a sealant layer 11, a second sealant layer 11', a first adhesive layer 12, a first anticorrosion layer 13, a separator (metal foil) 14, and a second anticorrosion layer in this order. The layer 15, the second adhesive layer 16, and the substrate layer 17.

That is, the laminate 10 of the present embodiment is composed of an eight-layer structure having a first anti-corrosion layer 13 and a second anti-corrosion layer 15 formed on both sides of the isolation layer 14. The sealant layer 11 and the second sealant layer 11' laminated on the corrosion layer 13 via the first adhesive layer 12, and laminated on the second anticorrosion layer 15 via the second adhesive layer 16 The base material layer 17.

Each layer will be described in detail below.

<Sealant layer 11>

The sealant layer 11 is a layer formed of block polypropylene, random polypropylene, and olefin-based elastomer.

In the present invention, "block polypropylene" (hereinafter, sometimes referred to as "block PP") refers to a mixture (Impact Copolymer) composed of polypropylene (homopolymer) and ethylene-propylene copolymer. Such a mixture, after preparing polypropylene (propylene homopolymer) by using raw material monomers, in the presence of the homopolymer Next, it is obtained by polymerizing ethylene and propylene, usually a mixture of ethylene-propylene rubber dispersed in polypropylene.

In addition, "random polypropylene" (hereinafter sometimes referred to as "random PP") means a propylene-ethylene random copolymer.

The polypropylene/ethylene-propylene copolymer ratio, propylene/ethylene ratio, degree of polymerization, etc. in block polypropylene and random polypropylene are not particularly limited, and can satisfy the block of formulas (1) to (4) described below. The method of PP and atactic polypropylene is appropriately determined.

In the present invention, the olefin-based elastomer is not particularly limited as long as it is an olefin-based polymer having characteristics as an elastomer.

Examples of olefin polymers include homopolymers such as polyethylene, polypropylene, poly-1-butene, and polyisobutylene; propylene-ethylene copolymers, ethylene-1-butene copolymers, and ethylene-1-hexene copolymers. Copolymers, ethylene-1-octene copolymer, propylene-ethylene-1-butene copolymer, propylene-1-butene copolymer, styrene-butadiene copolymer, styrene-ethylene copolymer and other copolymers.

In the present invention, the block PP, random PP, and olefin elastomer constituting the sealant layer 11 satisfy the relationship of the following formulas (1) to (4).

A>B (1)

A>C (2)

A+B+C=100 (3)

mp(A)>mp(B)≧mp(C) (4)

A is the content ratio (mass ratio) of block polypropylene, B is the content ratio (mass ratio) of random polypropylene, and C is the content ratio (mass ratio) of the olefin-based elastomer. mp (A) is the melting point of block polypropylene, mp (B) is the melting point of random polypropylene, and mp (C) is the melting point of the olefin elastomer.

As shown in the above formula (3), the resin component of the sealant layer 11 is composed of only three components of block PP, random PP, and olefin elastomer. The number of types of polymers constituting the sealant layer 11 is not limited as long as they are classified into any one of these three components, and may be three or more. For example, as the olefin elastomer, two or more types of olefin elastomers having different compositions or physical properties may be used in combination.

In addition, as shown in formula (4), among the block PP, random PP, and olefin elastomer constituting the sealant layer 11, the block PP has the highest melting point. In addition, random PP and olefin elastomer have the same melting point, or compared to olefin elastomer, random PP has a higher melting point.

In this way, by including polymers having at least two or more different melting points in the sealant layer 11, the sealant layer can be melted during the hot-melt connection by appropriately setting the temperature applied during the hot-melt connection of the sealant layer 11 A part of the polymer in 11, and a part of the polymer is in an unmelted state.

Furthermore, as shown in the above formulas (1) and (2), of the three components constituting the sealant layer 11, the sealant layer 11 contains the most block PP. Since the block PP containing the highest melting point component among the three components is the most, the main component of the sealant layer 11 does not melt until a relatively high temperature. By using the unmelted block PP as a support and using the other two molten components for hot-melt connection, the hot-melt connection can be performed while maintaining the mechanical strength of the sealant layer 11, and the resulting battery can also be improved. The mechanical strength of the body.

In addition, by making the sealant layer 11 contain a large amount of block PP, the heat resistance of the sealant layer 11 and the laminate 10 for battery exterior can be improved.

As described above, the sealant layer 11 contains the most block PP. another On the other hand, the relative content ratio (mass ratio) between the random PP and the olefin elastomer is not particularly limited. It can be B>C, C>B, or B=C, but it is preferably B≧C, and more preferably B>C.

Among them, the content of block PP (A in the above formulas (1) to (3)) is preferably 35 to 80% by mass, more preferably 35 to 60% by mass, even more preferably 35 to 50% by mass, and particularly preferred It is 35~45% by mass.

The content ratio of random PP (B in the above formulas (1) to (3)) is preferably 10 to 45% by mass, more preferably 20 to 45% by mass, still more preferably 25 to 40% by mass, and particularly preferably 30 ~40% by mass.

The content ratio of the olefin elastomer (C in the above formulas (1) to (3)) is preferably 10 to 40% by mass, more preferably 20 to 35% by mass, and particularly preferably 20 to 30% by mass.

In addition, the melting point (mp(A)) of the block PP is preferably 160°C or higher. The melting point (mp(B)) of random PP is preferably 120°C or more and less than 160°C. The melting point (mp(C)) of the olefin-based elastomer is preferably 40°C or more and less than 160°C, more preferably 120°C or more and less than 160°C.

The thickness of the sealant layer 11 may be, for example, 1 to 200 μm, preferably 5 to 100 μm, and more preferably 5 to 40 μm.

In the present invention, all the sealant layers contain three types of block PP, random PP, and olefin elastomer. Conventionally, the sealant layer of many laminates for battery exterior packaging has been manufactured by using only one of these resins. However, in a sealant layer composed of only one of these resins, in addition to the advantages provided by the characteristics of each resin, there are also disadvantages, and therefore further improvement in characteristics is required.

For example, when using a sealant layer composed of only block PP, the block PP Since it has high heat resistance, it has the advantage of improving the heat resistance of the entire sealant layer and the laminate for battery exterior. In addition, by using block PP with high resin strength, there is also an advantage that a laminate for battery exterior packaging with excellent mechanical strength can be obtained. On the other hand, when a sealant layer composed of block PP is used, it is necessary to set the heat of heat-sealing (hot-melt connection) when the battery exterior laminate is used to produce a battery exterior body. In addition to poor production efficiency, there is also the possibility of defects during heat sealing and a decrease in yield.

In addition, when a sealant layer composed of only random PP is used, the production efficiency and yield during heat sealing are sufficient, but there is a possibility that the heat resistance of the sealant layer and the laminate for battery exteriors itself may decrease.

Furthermore, when a sealant layer composed only of an olefin-based elastomer is used, since the olefin-based elastomer generally has a relatively low melting point, it can be heat-sealed at low temperatures, and the production efficiency and yield during heat-sealing become very high. On the other hand, due to the low melting point of the olefin-based elastomer, there is a possibility that the heat resistance of the entire sealant layer and the laminate for battery exterior may be reduced.

As described above, when used in a laminate for battery exterior packaging, the sealant layer in which each resin is used alone has characteristics that require improvement. In this regard, in the laminate for battery exterior packaging of the present invention, by using not only three resins having a specific melting point relationship, but also using these three resins in a specific ratio, it is possible to produce the respective resins as described above. Advantages, and can complement its disadvantages. According to the laminate for battery exterior packaging of the present invention using such a sealant layer, the heat resistance and cold resistance can be improved, and the battery exterior can be heat-sealed at a lower temperature when preparing the battery exterior body, so that the battery can be improved The production efficiency and yield during the preparation of the exterior body.

<Second Sealant Layer 11'>

The laminate 10 for battery exterior packaging of the present embodiment has a second sealant layer 11'. In the present invention, the second sealant layer 11' has an arbitrary structure.

The second sealant layer 11' is a layer provided on the outer layer side (separation layer side) of the sealant layer 11 as the innermost layer, and is provided with the sealant layer 11 to fuse the sealant layers during thermal fusion bonding. The functional layer. By providing the second sealant layer 11' in addition to the sealant layer 11, the heat-sealing strength at the time of thermal fusion connection can be further improved.

The second sealant layer 11' is not particularly limited as long as it has a different composition from the sealant layer 11. However, it is preferably a layer made of polyolefin. Examples of the layer made of polyolefin include polyethylene, polypropylene, poly-1-butene, polyisobutylene, random copolymers of propylene and ethylene or α-olefin, block polypropylene, and olefin elastomers.

Among them, from the viewpoint of improving the adhesiveness with the sealant layer 11 and the first adhesive layer 12, the second sealant layer 11' is preferably selected from homopolypropylene (propylene homopolymer), propylene-ethylene A layer consisting of one or more of the group consisting of random copolymer (random PP), block propylene and olefin elastomer. Among them, a layer composed of a block polypropylene and/or an olefin elastomer is more preferable, and a layer composed of a block polypropylene and an olefin elastomer is particularly preferable.

The second sealant layer 11' may have a single-layer structure or a multilayer structure.

The melting point of the material used in the second sealant layer 11' is not particularly limited as long as it has the heat resistance necessary for the laminate 10 for battery exterior packaging.

The thickness of the second sealant layer 11' may be, for example, 1 to 200 µm, preferably 5 to 100 µm, and more preferably 5 to 40 µm.

When the second sealant layer 11' is provided, the total thickness of the sealant layer 11 and the second sealant layer 11' can be, for example, 0.5-50 m, preferably 2-30 m, and more preferably 5-20 m.

<First Adhesive Layer 12>

The first adhesive layer 12 is a layer provided for bonding the sealant layer 11 provided with the second sealant layer 11' and the isolation layer 14 with the first anti-corrosion layer 13 formed on the surface as required.

As the adhesive forming the first adhesive layer 12, the material is not particularly limited as long as it can bond the above-mentioned layers well. However, for example, from the viewpoint of satisfying the adhesiveness and storage modulus, It is preferably a layer composed of an adhesive containing an acid-modified polyolefin resin (A) and a crosslinkable compound (B).

Hereinafter, the acid-modified polyolefin resin (A) may be referred to as "(A) component", and the crosslinkable compound (B) may be referred to as "(B) component".

(Acid modified polyolefin resin (A))

In the present invention, the acid-modified polyolefin resin (A) (component (A)) refers to a polyolefin resin modified with an unsaturated carboxylic acid or its derivative. The polyolefin resin has a carboxyl group or Acidic functional groups such as carboxylic anhydride groups.

The component (A) is obtained by modification of a polyolefin-based resin with an unsaturated carboxylic acid or a derivative thereof, or copolymerization of an acidic functional group-containing monomer and olefins. Among them, as the component (A), those obtained by acid-modifying a polyolefin resin are preferable.

Examples of the acid modification method include graft modification of a polyolefin resin and an acidic functional group-containing monomer in the presence of a radical polymerization initiator such as an organic peroxide or an aliphatic azo compound.

Examples of the polyolefin resin include polyethylene, polypropylene, poly-1-butene, polyisobutylene, copolymers of propylene and ethylene, copolymers of propylene and olefin monomers, and the like.

Examples of the olefin-based monomer during the copolymerization include 1-butene, isobutene, 1-hexene and the like.

The copolymer may be a block copolymer or a random copolymer.

Among them, as the polyolefin resin, a polypropylene resin polymerized from propylene such as homopolypropylene (propylene homopolymer), a copolymer of propylene and ethylene, and a copolymer of propylene and butene as a raw material; particularly preferably propylene- 1-Butene copolymer, that is, a polyolefin resin having methyl and ethyl groups on the side chain. By containing 1-butene, the molecular motion of the resin when heated can be promoted, and the chance of contact between the cross-linking points of the component (A) and the component (B) described later can be increased. As a result, the adhesion to the adherend can be further improved. Tightness.

The acidic functional group-containing monomer is a compound having an ethylenic double bond, a carboxyl group, or a carboxylic anhydride group in the same molecule, and various unsaturated monocarboxylic, dicarboxylic or dicarboxylic acid anhydrides can be cited.

Examples of acidic functional group-containing monomers (carboxyl group-containing monomers) having a carboxyl group include acrylic acid, methacrylic acid, maleic acid, nadic acid, fumaric acid, itaconic acid, citraconic acid, and croton Acid, isocrotonic acid, tetrahydrophthalic acid, internal bicyclo[2.2.1]-5-heptene-2,3-dicarboxylic acid (norbornenic acid (endic acid)), etc. α, β- Saturated carboxylic acid monomer.

Examples of acidic functional group-containing monomers having carboxylic anhydride groups (carboxylic acid anhydride group-containing monomers) include maleic anhydride, nadic anhydride, itaconic anhydride, citraconic anhydride, and anhydrous endic acid. Unsaturated dicarboxylic anhydride mono body.

In the (A) component, these acidic functional group-containing monomers may be used singly or in combination of two or more.

Among them, the acidic functional group-containing monomer is preferably a monomer containing an acidic functional group that reacts well with the crosslinkable functional group in the component (B) described later; from the viewpoint of high reactivity with the crosslinkable functional group, more An acidic functional group-containing monomer having an acid anhydride group is preferred; a carboxylic anhydride group-containing monomer is more preferred; and maleic anhydride is particularly preferred.

When a part of the acidic functional group-containing monomer used in the acid modification is not reacted, in order to prevent the adhesive force from being reduced by the unreacted acidic functional group-containing monomer, it is preferable to use a monomer that has been removed in advance. As the (A) component.

In the (A) component, the polyolefin resin or the olefin-derived component is preferably 50 parts by mass or more relative to 100 parts by mass of the total amount of the (A) component.

The melting point of (A) component is not particularly limited.

When the first adhesive layer 12 is used as an adhesive layer for dry lamination, the melting point of component (A) is preferably 50-100°C, preferably 60-98°C, more preferably 70-98°C, and further Preferably it is 75-95 degreeC.

By making the melting point of the component (A) above the above lower limit value, the heat resistance of the first adhesive layer 12 can be improved. As a result, the adhesion of the sealant layer 11 through the first adhesive layer 12 can be improved. The heat resistance and durability of the first anticorrosion layer 13 after the isolation layer 14.

On the other hand, by making the melting point of the component (A) below the above upper limit, When the component (A) is dissolved in an organic solvent to obtain a solvent-based adhesive for dry lamination, the component (A) is easily dissolved in the organic solvent to obtain a more uniform adhesive, making the component (A) It reacts well with component (B) and improves adhesion and durability. In addition, by using the component (A) having a melting point equal to or lower than the above upper limit, the temperature during dry lamination via the first adhesive layer 12 or the aging temperature after lamination can be lower. As a result, in the sealant layer 11 bonded using the first adhesive layer 12, wrinkles due to heat are less likely to occur, which not only improves the yield during production, but also relaxes the heat resistance of the sealant layer 11 Therefore, the selection range of the material of the sealant layer 11 can be expanded. In addition, as a result of the ability to perform the lamination process at a lower temperature, the time for the lamination process can be shortened, and the energy necessary for the lamination process can also be reduced, so that the production efficiency can be improved and the energy consumed can be reduced.

On the other hand, the adhesive used in the formation of the first adhesive layer 12 does not contain an organic solvent. When the component (A) and the component (B) described later are melt-kneaded to form an adhesive, the component (A) The melting point is preferably 100°C to 180°C. The first adhesive layer 12 composed of such an adhesive is suitable for use as an adhesive layer for thermal lamination.

By using the component (A) having a melting point in the above-mentioned range, even when using conventional methods and ordinary equipment, the component (A) can be melt-kneaded at a temperature sufficiently higher than the melting point of the component (A) and the component (B) described later. )ingredient. In addition, when the component (A) and the component (B) described later are reacted by melt kneading, it is preferable that the component (B) has a lower melting point than the component (A). By using (A) having a melting point in the above range Ingredients can increase the degree of freedom in selecting the (B) ingredient.

In addition, as described above, it is preferable that the melting point of the component (A) is higher than the melting point of the component (B) described later, more preferably the melting point of the component (A) is higher than the melting point of the component (B) by 10°C or more, and even more preferably by 20°C or more. It is particularly preferred that the temperature is higher than 30°C. By making the melting point of the component (A) sufficiently higher than that of the component (B), during the melt-kneading, the component (B) melts first, and penetrates into the component (A) while maintaining the shape of the resin. The component (B) reacts with the component, and as a result, good durability can be obtained.

(A) The molecular weight of component (A) is not particularly limited, as long as the desired melting point can be obtained sufficiently, but resins with a molecular weight of 10,000 to 800,000 are generally used, and resins with a molecular weight of 50,000 to 650,000 are preferably used, and more preferably A resin having a molecular weight of 80,000 to 550,000 is used, and a resin having a molecular weight of 100,000 to 450,000 is more preferably used.

Among them, as the component (A), maleic anhydride-modified polypropylene is preferred from the viewpoints of adhesiveness and durability.

(Crosslinkable compound (B))

The component (B) is not particularly limited as long as it is a compound capable of imparting crosslinkability to the first adhesive layer, but a compound having a crosslinkable functional group is preferred. As the compound having a crosslinkable functional group, a compound having an epoxy group or an oxazoline group is preferable. Specifically, as a preferable compound, an epoxy group-containing polyolefin resin (b1) can be cited; The compound (b2) containing multiple epoxy groups mentioned in (b1); oxazoline group-containing styrene resin (b3). The details are described separately below.

‧Polyolefin resin containing epoxy groups (b1)

In the present invention, epoxy group-containing polyolefin resin (b1) (hereinafter sometimes It is called "(b1) component". ) It has a main chain obtained by copolymerizing a monomer containing an olefin compound and an epoxy group-containing vinyl monomer, and a side chain bonded to the main chain, and has a melting point of 80 to 120°C.

‧Main chain

(b1) The main chain of the component is obtained by copolymerizing an olefin compound, an epoxy group-containing vinyl monomer, and other arbitrary monomers used as needed.

Examples of the olefin compound include olefin monomers such as ethylene, propylene, 1-butene, isobutylene, 1-hexene, and α-olefin.

Examples of the epoxy group-containing vinyl monomer include glycidyl esters such as glycidyl methacrylate (GMA) and glycidyl acrylate, glycidyl ethers such as allyl glycidyl ether, and epoxybutylene. And other epoxy olefins.

As the olefin compound and the epoxy group-containing vinyl monomer, one type may be used alone, or two or more types may be used simultaneously.

(b1) The main chain of the component may contain one or more other monomers in addition to the olefin compound and the epoxy-containing vinyl monomer. The other monomers are not particularly limited as long as they can be copolymerized with olefin compounds and epoxy-containing vinyl monomers. Examples include (meth)acrylate monomers, (meth)acrylate monomers, and (meth)acrylate monomers. ester) monomer, (meth)acrylamide monomer, styrene monomer, etc.

In the copolymer that becomes the main chain of component (b1), the composition ratio of each monomer (compound) is not particularly limited, but it is preferable to copolymerize 10 to 30% by mass with respect to all monomers constituting the main chain of component (b1) A copolymer obtained by copolymerizing 10 to 20% by mass of an epoxy-containing vinyl monomer is more preferable. By using the epoxy-containing vinyl monomer within the above range, the adhesion to the adherend can be appropriately improved Sex.

Among them, as the main chain of the component (b1), a copolymer obtained by copolymerizing an olefin compound and an epoxy group-containing vinyl monomer is preferable, and a copolymer of ethylene and glycidyl methacrylate is particularly preferable.

‧Side chain

The component (b1) has a side chain bonded to the main chain to improve the strength, adhesiveness, and synthesis characteristics of the olefin-based copolymer. The side chain is not particularly limited, and styrenic resins (styrene-containing polymers) such as polystyrene and styrene-acrylonitrile copolymers are mentioned; methyl (meth)acrylate and ethyl (meth)acrylate , (Meth)acrylic resins obtained by polymerizing at least one of alkyl (meth)acrylate monomers such as butyl (meth)acrylate and pentyl (meth)acrylate.

Among them, the side chain of the component (b1) is preferably a polymer containing styrene, and examples thereof include polystyrene and styrene-acrylonitrile copolymers. Among them, polystyrene is particularly preferred.

When the component (b1) is a polymer containing polystyrene as a side chain, the fluidity in the molten state is improved. Therefore, it can be considered that the heat bonding has moderate fluidity, and the epoxy group is easy to contact with the adherend, which can improve the bonding strength and durability.

The component (b1) having the above-mentioned main chain and side chain can be obtained by using, for example, a main chain copolymer obtained by a conventional method, a monomer constituting the side chain, and free radicals such as organic peroxides or aliphatic azo compounds. It is obtained by graft polymerization of a polymerization initiator.

(b1) The melting point of the component is 80 to 120°C, preferably 90 to 110°C. It can be obtained by appropriately selecting the main chain and the monomer types constituting the side chain. (B1) component of the melting point.

By using the component (b1) having a melting point in the above range, it is possible to melt-knead the component (A) and the component (A) at a temperature sufficiently higher than the melting point of the component (b1) even when using a conventional method and a normal apparatus. The component (b1) can obtain an adhesive or adhesive layer with excellent durability. In addition, when the (A) component and the (b1) component are reacted by melt kneading, it is preferable that the melting point of the (b1) component is lower than that of the (A) component. By using (b1) having a melting point in the above range Ingredients can increase the degree of freedom in selecting the (A) ingredient.

As such a component (b1), commercially available products such as MODIPER A1100, A4100, and A4400 (all product names) manufactured by NOF Corporation can be used.

‧Compounds containing multiple epoxy groups (b2)

The compound (b2) containing a plurality of epoxy groups (hereinafter may be referred to as "(b2) component") is a compound that does not correspond to (b1). The component (b2) may be a low molecular compound or a high molecular compound. The component (b2) is preferably a polymer compound (resin) from the viewpoint of good miscibility and compatibility with the component (A). On the other hand, when the adhesive is a solvent-type adhesive for dry lamination, the component (b2) is preferably a low-molecular compound from the viewpoint of good solubility in an organic solvent.

(b2) The structure of the component is not particularly limited as long as it has a plurality of epoxy groups. For example, phenoxy resin synthesized from bisphenols and epichlorohydrin; novolac epoxy resin; bisphenol type Epoxy and so on. Among them, since the epoxy content per molecule is high, and in particular, a dense cross-linked structure can be formed with the component (A), novolac epoxy resin is preferably used.

In the present invention, the novolac epoxy resin refers to a compound having a novolac resin obtained by condensing phenol and formaldehyde acid as a basic structure and introducing an epoxy group into a part of the structure. The amount of epoxy groups introduced per molecule in the novolac epoxy resin is not particularly limited, but since epoxy raw materials such as epichlorohydrin are reacted with the novolac resin, the novolac resin is converted to the phenol that is more present in the novolac resin. Since the hydroxyl group introduces many epoxy groups, it is usually a polyfunctional epoxy resin.

Among them, as the novolac epoxy resin, a bisphenol A novolac epoxy resin having a novolac structure as a basic skeleton and a bisphenol A structure at the same time is preferable. In addition, the bisphenol A structure in the epoxy resin may be a structure derived from bisphenol A, and the hydroxyl groups at both ends of bisphenol A may be replaced by groups such as epoxy-containing groups.

As an example of bisphenol A novolac epoxy resin, the resin represented by the following general formula (1) can be mentioned.

In the general formula (1), R ¹ to R ⁶ are each independently a hydrogen atom or a methyl group, n is an integer of 0 to 10, and R ^X is a group having an epoxy group.

In the general formula (1), R ¹ to R ⁶ are each independently a hydrogen atom or a methyl group. When n is an integer of 2 or more, R ³ and R ⁴ may be the same or different.

In the resin represented by the general formula (1), it is preferable to satisfy at least one of the following conditions (i) to (iii).

(i) R ¹ and R ² are both methyl groups, (ii) R ³ and R ⁴ are both methyl groups, (iii) R ⁵ and R ⁶ are both methyl groups

For example, by satisfying the above (i), in the general formula (1), the carbon atom to which R ¹ and R ² are bonded, and the two hydroxyphenyl groups to which the carbon atom is bonded to form a structure derived from bisphenol A.

In the formula (1), R ^X is a group having an epoxy group. Examples of the group having an epoxy group include an epoxy group, a combination of an epoxy group and an alkylene group, and the like. Among them, a glycidyl group is preferred.

The epoxy equivalent of the bisphenol A novolac epoxy resin is preferably 100 to 300, and more preferably 200 to 300. The epoxy equivalent (g/eq) is the molecular weight of the epoxy resin per epoxy group, and the smaller the value, the more epoxy groups in the resin. By using an epoxy resin with a small epoxy equivalent, even when the addition amount of the epoxy resin is small, the adhesion between the epoxy resin and the adherend is good, and the epoxy resin and the said Acid modified polyolefin resin.

As such a novolac epoxy resin, jER154, jER157S70, jER-157S65 manufactured by Mitsubishi Chemical Corporation; EPICLON N-730A, EPICLON N-740, EPICLON N-770, EPICLON N-775 (above , All are product names) and other markets Products sold.

By using the epoxy resin as described above, both the acidic functional group of the above-mentioned component (A) and the epoxy group of the component (b2) serve as functional groups for the adherend (especially the functional groups such as the carboxyl group of the first anticorrosion layer 13) Since it functions as an adhesive functional group, it is considered that the isolation layer 14 having the first anticorrosion layer 13 on the surface of the sealant layer 11 can achieve excellent adhesiveness.

In addition, a part of the acidic functional group of the component (A) and a part of the epoxy group of the component (b2) react to form a crosslinked structure of the component (A) and the component (b2) in the first adhesive layer 12, As a result, it can be seen that the strength of the first adhesive layer 12 is enhanced by the cross-linked structure, and not only excellent adhesiveness is obtained, but also good durability is obtained.

‧Styrenic resin containing oxazoline groups (b3)

By using the oxazoline group-containing styrene resin (b3) (hereinafter sometimes referred to as "(b3) component") as the (B) component, the oxazoline group and the acidic functional group of the (A) component (For example, carboxyl group, carboxylic acid group, etc.) react and form a crosslinked structure. For example, when the acidic functional group of the component (A) is a carboxyl group, the following crosslinking reaction is caused to form an amidoester bond. As a result, it can be seen that the strength of the resin is enhanced by the cross-linked structure, and excellent adhesiveness is obtained as well as good durability.

Among them, the component (b3) is preferably a resin obtained by copolymerizing a styrene-based monomer and an oxazoline group-containing monomer.

As the styrene monomer, styrene and its derivatives can be used. Specifically, styrene, α-methylstyrene, methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, diethylstyrene, triethylstyrene, Alkyl styrenes such as propyl styrene, butyl styrene, hexyl styrene, heptyl styrene, and octyl styrene; halogens such as chlorobenzene, fluorostyrene, bromostyrene, dibromo styrene, and iodostyrene On behalf of styrene and so on. Among them, styrene is preferred.

As long as the oxazoline group-containing monomer is a monomer that contains an oxazoline group and can be copolymerized with a styrene monomer, its skeleton is not particularly limited, and a monomer having an oxazoline group and a vinyl group can be suitably used .

Examples of the oxazoline group-containing vinyl monomer include 2-vinyl-2-oxazoline, 5-methyl-2-vinyl-2-oxazoline, 4,4-dimethyl-2 -Vinyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 4,4-dimethyl-2-isopropenyl-2-oxazoline, 4-propenyl-hydroxymethyl 2,4-Dimethyl-2-oxazoline, 4-methacryloyl hydroxymethyl-2,4-dimethyl-2-oxazoline, 4-methacryloyl hydroxymethyl 2-phenyl-4-methyl-2-oxazoline, 2-(4-vinylphenyl)-4,4-dimethyl-2-oxazoline, 4-ethyl-4- Hydroxymethyl-2-isopropenyl-2-oxazoline, 4-ethyl-4-ethoxycarbonylmethyl-2-isopropenyl-2-oxazoline, etc. Among them, 2-isopropenyl-2-oxazoline is preferred.

As the styrene-based monomer and the oxazoline group-containing monomer, one type may be used alone, or two or more types may be used simultaneously.

In addition, the component (b3) may contain one or more other monomers in addition to the styrene monomer and the oxazoline group-containing monomer. Other monomers are not particularly limited as long as they can be copolymerized with these monomers. For example, (meth)acrylate (acrylate) monomers, (meth)acrylate (acryl ester) monomers, (former) Base) acrylamide monomer and the like.

In the component (b3), the composition ratio of each monomer is not particularly limited, but relative to all the monomers constituting the component (b3), it is preferable to add 5-50% by mass, more preferably 10-30% by mass of oxazole A resin obtained by copolymerization of a monomer of a line group. By using the oxazoline group-containing monomer within the above-mentioned range, the (A) component and the (b3) component can be sufficiently crosslinked to obtain good durability.

(b3) The number average molecular weight of the component is preferably 30,000 to 250,000, more preferably 50,000 to 200,000, still more preferably 60,000 to 100,000, and most preferably 60,000 to 80,000. By using the component (b3) having a number average molecular weight in the above range, the compatibility of the component (A) and the component (b3) can be improved, and the component (A) and the component (b3) can be sufficiently crosslinked.

As such (b3) component, products sold on the market such as EPOCROS RPS-1005 (trade name) manufactured by Nippon Shokubai Co., Ltd. can be used.

By using the above-mentioned (B) component, both the acidic functional group of the above-mentioned (A) component and the crosslinkable functional group of the (B) component are used as a component for the adherend (especially the first anticorrosive layer 13). Functional groups such as carboxyl groups) function as adhesive functional groups, so that the sealant layer 11 or the first sealant layer 11', and the isolation layer 14 having the first anticorrosive layer 13 on the surface can achieve excellent adhesion .

In addition, a part of the acidic functional group of the component (A) reacts with a part of the crosslinkable functional group of the component (B) to form a crosslinked structure of the component (A) and the component (B) in the first adhesive layer 12 As a result, the strength of the first adhesive layer 12 is enhanced through the cross-linked structure, and excellent adhesiveness is obtained. At the same time, good durability was also obtained.

In the first adhesive layer 12, it is preferable to contain 1-20 parts by mass of the component (B) relative to 100 parts by mass of the component (A); and it is more preferable to contain 5 to 100 parts by mass of the component (A). 10 mass parts of (B) component; It is especially preferable to contain 5-7 mass parts of (B) component with respect to 100 mass parts of (A) components.

(Any ingredient)

The adhesive used in the present invention may further contain an organic solvent, or may not contain an organic solvent.

By containing an organic solvent to form a liquid adhesive, it is possible to form a solvent-based adhesive for dry lamination. The first adhesive layer 12 can be formed by applying such a liquid adhesive on a lower layer (for example, the surface of the isolation layer 14 on which the first anticorrosion layer 13 is provided) and drying. By selecting coating instead of extrusion molding, the adhesive layer can be formed with a thinner layer, and the adhesive layer can be thinned and the entire laminate using the adhesive layer can be made thinner.

On the other hand, when the organic solvent is not contained, by melt-kneading the (A) component and the (B) component, and then performing extrusion molding or the like, an adhesive layer suitable for thermal lamination or the like can be formed.

When an organic solvent is contained, as the organic solvent used, as long as the above-mentioned (A) component, (B) component and other optional components used as necessary (described in detail later) can be appropriately dissolved and formed into a uniform solution, It is not particularly limited, and as the solvent of the solution adhesive, any solvent among conventional solvents can be used. In addition, the liquid adhesive is usually coated on the adherend (for example, the surface of the isolation layer 14 on which the first anticorrosion layer 13 is provided), and can be The organic solvent is volatilized by heating or the like for use. Therefore, from the viewpoint of easy volatilization, the organic solvent is preferably an organic solvent having a boiling point of 150°C or less.

Specific examples of organic solvents include toluene, xylene, anisole, ethyl benzyl ether, cresol methyl ether, diphenyl ether, dibenzyl ether, phenyl ethyl ether, butyl phenyl ether, and ethyl benzene. , Diethylbenzene, pentylbenzene, cumene, cymene, mesitylene and other aromatic solvents; n-hexane and other aliphatic solvents; methyl ethyl ketone, acetone, cyclohexanone, methyl normal Ketone solvents such as pentanone, methyl isoamyl ketone, 2-heptanone; methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methoxy Ester solvents such as methyl propionate and ethyl ethoxypropionate; alcohol solvents such as methanol, ethanol, and isopropanol; polyhydric alcohol solvents such as ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol.

The organic solvent may be used alone or in combination of two or more and used as a mixed solvent. When using a mixed solvent, it is preferable to use an organic solvent that dissolves the component (A) well and an organic solvent that dissolves the component (B) well in combination. As such a combination, a combination of toluene that dissolves the component (A) well and methyl ethyl ketone that dissolves the component (B) well is preferred. When using a mixed solvent, it is also possible to dissolve the above-mentioned (A) component, (B) component, etc., after mixing two or more organic solvents in advance; it is also possible to make each component of (A) component and (B) component After dissolving in each good solvent, multiple organic solvents in which each component is dissolved are mixed.

When multiple organic solvents are used in combination, the ratio of each organic solvent is not particularly limited. For example, when toluene and methyl ethyl ketone are used in combination, their mixing ratio is preferably toluene: methyl ethyl ketone = 60 to 95: 5 to 40 (mass ratio), more preferably Toluene: A and B Ketone = 70~90: 10~30 (mass ratio).

The adhesive used in the present invention may further contain other components in addition to the above-mentioned (A) component, (B) component and organic solvent. Examples of other components include additives having miscibility or additive resins, and more specifically, catalysts, crosslinking agents, plasticizers, stabilizers, colorants, etc. can be used.

The solid content of the adhesive used in the present invention preferably contains more than 50 parts by mass and 99.5 parts by mass or less of (A) component, and 0.5 parts by mass or more and less than 50 parts by mass of (B) component. That is, among the solid components of the adhesive, the component (A) is more than half of the mass ratio, and the adhesive used in the present invention has the component (A) as the main component. More preferably, it is 0.5 to 30 parts by mass relative to 70 to 99.5 parts by mass of (A) component, and (B) component is 0.5 to 30 parts by mass; more preferably, 1 to 20 parts by mass relative to 80 to 99 parts by mass of (A) component and (B) component Parts; It is particularly preferable that the (B) component is 2 to 10 parts by mass relative to 90 to 98 parts by mass of the (A) component.

In addition, even when the adhesive used in the present invention contains solid components other than the (A) component and (B) component as optional components, the (A) component must be the main component. Therefore, even when an arbitrary component is contained, the (A) component exceeds 50 parts by mass in the total solid content of the adhesive. For example, a binder containing 70 to 99.5 parts by mass of the (A) component, 0.5 to 29.5 parts by mass of the (B) component, and 0.5 to 29.5 parts by mass of other components in the total solid content can be cited.

When the adhesive used in the present invention contains an organic solvent, the amount of the organic solvent used is not particularly limited as long as it can dissolve each component such as (A) component, (B) component, and optional components. Excellent ingredient concentration It is selected from 3 to 30% by mass, more preferably from 5 to 25% by mass, and even more preferably from 7 to 20% by mass.

The thickness of the first adhesive layer 12 may be, for example, 0.1 to 50 μm, preferably 0.5 to 10 μm, and more preferably 0.7 to 5 μm. By setting the thickness within this range, the sealant layer 11 provided with the second sealant layer 11' and the isolation layer 14 provided with the first anticorrosion layer 13 can be bonded with high adhesive force as needed, thereby preventing interlayer peeling .

<The first anti-corrosion layer 13>

In this embodiment, the first anti-corrosion layer 13 is a layer for preventing corrosion of the isolation layer 14 due to rust or the like.

The first anticorrosive layer 13 preferably contains a halogenated metal compound, and the halogenated metal compound described later may be directly plated on the surface of the isolation layer 14. By providing such a first anti-corrosion layer 13, a good anti-rust effect can be imparted to the metal foil.

In addition, the first anticorrosion layer 13 preferably contains a water-soluble resin, a chelating agent, or a crosslinking compound in addition to the halogenated metal compound. Therefore, as the first anti-corrosion layer 13, it is preferable to contain a halogenated metal compound, a water-soluble resin, and a chelating agent or a cross-linking compound; the first anti-corrosion layer 13 preferably contains a halogenated compound, a water-soluble resin, a chelating agent or After the aqueous solution of the crosslinkable compound is applied on the lower layer, it is dried and cured to form it. Hereinafter, the material forming the first anti-corrosion layer 13 may be referred to as "anti-corrosion treatment agent".

(Metal halide compound)

The halogenated metal compound has the effect of improving chemical resistance such as electrolyte resistance. That is, the surface of the isolation layer 14 can be passivated, and the resistance to the electrolyte is improved. Corrosive. When the first anticorrosion layer 13 contains a water-soluble resin described later, the halogenated metal compound also has a function of crosslinking the water-soluble resin.

Regarding the halogenated metal compound, it is preferable to have water solubility in view of the miscibility with the water-soluble resin described later or the case of being dispersed in a water-soluble medium and applied.

Examples of the halogenated metal compound include chromium halides, iron halides, zirconium halides, titanium halides, hafnium halides, titanium hydrohalides, and their salts. Examples of the halogen atom include chlorine, bromine, and fluorine, and chlorine or fluorine is preferable. In addition, fluorine is particularly preferred. By containing fluorine in the halogenated metal compound, hydrofluoric acid (HF) can be generated from the anticorrosive treatment agent according to conditions.

In addition, the halogenated metal compound may have atoms other than halogen atoms and metals.

Among them, the halogenated metal compound is preferably a chloride or fluoride of iron, chromium, manganese, or zirconium.

(Water-soluble resin)

As the water-soluble resin, it is preferable to use at least one selected from the group consisting of polyvinyl alcohol resins or derivatives thereof, and polyvinyl ether resins.

The polyvinyl alcohol resin or its derivative is preferably a polyvinyl alcohol resin or a modified polyvinyl alcohol resin.

The polyvinyl alcohol resin can be prepared, for example, by saponifying a polymer of a vinyl ester monomer or a copolymer thereof.

Examples of polymers or copolymers of vinyl ester monomers include fatty acid vinyl esters such as vinyl formate, vinyl acetate, and vinyl butyrate, or vinyl ester monomers such as aromatic vinyl esters such as vinyl benzoate. Body homopolymers or copolymers, and copolymers with other monomers that can be copolymerized.

The degree of saponification of the polyvinyl alcohol resin or the modified polyvinyl alcohol resin is preferably 90 mol% or more, more preferably 90 to 99.9 mol%, and still more preferably 95 to 99 mol%.

By making the (modified) polyvinyl alcohol resin both have a hydrophobic group derived from the side chain of the polyvinyl ester (for example, in the case of vinyl acetate, the hydrophobic group is an acetyl group), and the hydrophilic group obtained by saponification As a result, the hydroxyl group can react favorably with the surface of the metal foil compared to a resin having a saponification degree of 100 mol%, that is, only a hydrophilic hydroxyl group.

As the water-soluble resin, only one of polyvinyl alcohol resin or its derivative and polyvinyl ether resin may be used, or both may be used at the same time.

(Chelating agent)

Chelating agents are materials that can coordinately bind to metal ions and form metal ion complexes.

The chelating agent combines the metal compound (chromium oxide, etc.) derived from the halogenated metal compound with the water-soluble resin to increase the compressive strength of the first anti-corrosion layer 13. Therefore, the thickness of the first anti-corrosion layer 13 is, for example, more than 0.2 μm , 1.0 μm or less, the first anti-corrosion layer 13 will not become brittle and crack or peel off. Therefore, the adhesion strength and adhesion between the isolation layer 14 and the first adhesive layer 12, and the adhesion strength and adhesion between the isolation layer 14 and the layer on the upper layer side can be improved.

In addition, the chelating agent chemically reacts with the water-soluble resin or the halogenated metal compound, thereby having the effect of making the water-soluble resin water resistant.

As the chelating agent, for example, aminocarboxylic acid chelating agents, phosphonic acid chelating agents, hydroxycarboxylic acids, and (poly)phosphoric acid chelating agents can be used.

(Crosslinking compound)

The crosslinkable compound refers to a compound that can react with the water-soluble resin to form a crosslinked structure. By using such a cross-linking compound, the above-mentioned water-soluble resin and the cross-linking compound can form a dense cross-linked structure in the first anti-corrosion layer 13, and the passivation and corrosion resistance of the surface of the isolation layer 14 can be further improved.

In the anti-corrosion treatment agent, the chelating agent and the cross-linking compound may be used either alone or both. Among them, it is preferable to use any one of a chelating agent and a crosslinking compound in combination with the above-mentioned halogenated metal compound and a water-soluble resin.

The anti-corrosion treatment agent can be prepared by dissolving a water-soluble resin, a halogenated metal compound, and a chelating agent and/or a crosslinking compound in a solvent containing water. Water is preferred as the solvent.

The solid content concentration in the anti-corrosion treatment agent can be appropriately determined in consideration of the coatability of the first anti-corrosion layer 13 and the like, but it can usually be 0.1 to 10% by mass.

The thickness of the first anticorrosion layer 13 is preferably 0.05 μm or more, more preferably more than 0.1 μm. By making the thickness of the first anti-corrosion layer 13 at least 0.05 μm, the laminate 10 for battery exterior packaging is provided with sufficient corrosion resistance, and the adhesion between the separator layer 14 and the first adhesive layer 12 can be improved. Strength, and the bonding strength between the isolation layer 14 and the sealant layer 11.

In addition, the thickness of the first anti-corrosion layer 13 is preferably 1.0 μm or less, and more preferably 0.5 μm or less. By making the thickness of the first anti-corrosion layer 13 less than 1.0 μm, the bonding strength between the isolation layer 14 and the first adhesive layer 12 is improved, and the material cost can also be suppressed.

<Isolation layer 14>

In the laminate 10 for battery exterior packaging, the separator layer 14 plays an important role in reducing leakage of the contents sealed by the laminate (for example, leakage of the battery). In addition, by using a metal with high mechanical strength, when the battery exterior laminate 10 is used to form a recess for accommodating the battery by stretching, the occurrence of pinholes can be reduced. As a result, the number of laminates used can be reduced. Leakage of sealed contents (for example, battery leakage).

The isolation layer 14 is not particularly limited as long as it is an isolation layer formed by thinly extending a metal or an alloy, and examples include metal foils such as aluminum, copper, lead, zinc, iron, nickel, titanium, and chromium; stainless steel And other alloy foils. The stainless steel foil is not particularly limited as long as it is made of stainless steel such as austenitic, ferrite, or martensitic. Examples of austenites include SUS304, 316, and 301; examples of ferrites include SUS430; examples of martensites include SUS410.

Among them, aluminum foil or stainless steel foil is preferred from the viewpoint of workability, ease of acquisition, price, strength (puncture strength, tensile strength, etc.), corrosion resistance, and particularly, stainless steel foil is preferred from the viewpoint of puncture strength.

The thickness of the isolation layer 14 is preferably 100 μm or less, preferably 5 to 40 μm, more preferably 10 to 30 μm, and particularly preferably 10 to 20 μm. By setting the thickness of the separator layer 14 to be at least the above lower limit, sufficient mechanical strength can be provided to the battery exterior laminate 10, and when used in batteries such as secondary batteries, the durability of the battery can be improved. In addition, by setting the thickness of the separator layer 14 to be equal to or less than the above upper limit, the laminate 10 for battery exterior packaging can be made into a sufficiently thin laminate, and sufficient stretch workability can be imparted.

<Second Anticorrosion Layer 15>

The second anti-corrosion layer 15 has the same configuration as the first anti-corrosion layer 13. In this embodiment, the second anti-corrosion layer 15 is provided. However, in the present invention, the second anti-corrosion layer 15 has an arbitrary structure.

<Second Adhesive Layer 16>

The second adhesive layer 16 may have the same structure as the first adhesive layer 12, or may be a layer composed of an adhesive such as a usual polyurethane adhesive or epoxy adhesive. The thickness of the second adhesive layer 16 may be 0.5-10 μm, for example. By setting the thickness within this range, the base layer 17 and the isolation layer 14 can be bonded with high adhesive force, thereby preventing interlayer peeling. In this embodiment, the second adhesive layer 16 is provided, but in the present invention, the second adhesive layer 16 has an arbitrary configuration.

<Base layer 17>

The base material layer 17 is not particularly limited as long as it has sufficient mechanical strength. For example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyethylene terephthalate can be used. Polyester resins such as butanediol ester (PBT); polyamide resins such as nylon (Ny); polyolefin resins such as extended polypropylene (OPP); polyether ether ketone (PEEK), polyphenylene sulfide (PPS), etc. Synthetic resin film. Among them, PET films are preferred.

The thickness of the base layer 17 may be, for example, 1 to 50 μm, preferably 1 to 30 μm, and more preferably 3 to 11 μm.

The base material layer 17 may have a single-layer structure or a multilayer structure. As an example of the substrate layer 17 having a multilayer structure, a double-layer film in which a polyethylene terephthalate (PET) resin film is laminated on a biaxially stretched polyamide resin film (ONy) can be cited. In addition, the base material layer 17 can also be laminated with more than three layers The multilayer structure of the film.

In addition, in the embodiment shown in FIG. 1, the base layer 17 is the outermost layer. Therefore, the base layer 17 can have a desired color or design by containing a coloring material such as a pigment in addition to a resin.

The base layer 17 is preferably composed of a single-layer or multilayer film using a heat-resistant resin film having a melting point of 200° C. or higher. As such a heat-resistant resin film, for example, there are PET film, PEN film, PBT film, nylon film, PEEK film, PPS film, etc. However, PET film which is advantageous in terms of cost is particularly preferable. By using such a heat-resistant resin film, the heat resistance of the battery exterior laminate 10 can be improved, and the durability of the battery using the battery exterior laminate 10 can be improved.

In the laminate 10 for battery exterior packaging shown in FIG. 1, although the base material layer 17 is the outermost layer, a coating layer may be formed on the outer side of the base material layer 17.

The coating layer (first coating layer) is selected from polyurethane resin, acrylic resin, polyvinylidene chloride, vinylidene chloride-vinyl chloride copolymer resin, maleic anhydride modified polypropylene resin, polyester resin, epoxy resin Resin, phenol resin, phenoxy resin, fluororesin, cellulose ester resin, cellulose ether resin, polyamide resin, polyphenylene ether resin (PPE), polyphenylene sulfide resin (PPS), polyaryl ether resin (PAE) ), at least one resin in the resin group composed of polyether ether ketone resin (PEEK) is formed. The coating layer is preferably composed of a material having excellent heat resistance. These resins may be used singly or in combination of two or more kinds.

The coating layer is preferably a thin film cured layer formed by applying a solvent-based paint prepared by dissolving the resin in a common organic solvent and drying.

The formation of the coating layer improves the insulation of the laminate 10 for battery exterior packaging. At the same time, damage to the surface of the laminate 10 for battery exterior packaging can be prevented. In addition, even when the laminate 10 for battery exterior comes into contact with the electrolytic solution, changes in appearance (discoloration, etc.) can be prevented.

In addition, by adding a colorant or a pigment to the solvent-based paint that forms the coating layer, the coating layer can be colored. In addition, coloring or printing can also be applied to make the coating layer display characters, graphics, images, patterns, etc., to enhance the design sense.

The thickness of the coating layer may be, for example, 0.1 to 20 μm, and preferably 2 to 10 μm.

The thickness of the laminate 10 for battery exterior packaging is preferably 10 to 200 μm, more preferably 20 to 100 μm, and still more preferably 30 to 80 μm.

As the battery using the laminate 10 for battery exterior packaging, a battery using an organic electrolyte in an electrolyte such as a secondary battery such as a lithium ion battery or a capacitor such as an electric double layer capacitor or the like as a secondary battery can be cited. The organic electrolyte is usually a substance using carbonates such as propylene carbonate (PC), diethyl carbonate (DEC), and ethylene carbonate as a medium, but it is not particularly limited thereto.

The laminate for battery exterior packaging of the present invention can be prepared by a method having the following steps: for example, a step of forming the first anticorrosion layer 13 on one side of the separator layer 14 and forming on the formed first anticorrosion layer 13 The step of the first adhesive layer 12, and the arrangement so that the sealant layer 11 is in contact with the formed first adhesive layer 12 (or when the second sealant layer 11' is provided, so that the first The second sealant layer 11' is placed in contact with the first adhesive layer 12), and the laminate is laminated.

The detailed description is given below.

First, the first anti-corrosion layer 13 is formed on one side of the stainless steel foil 14.

Specifically, the above-mentioned anti-corrosion treatment agent is coated on the surface of the isolation layer 14 After that, heat drying is performed. At this time, only the first anti-corrosion layer 13 can be formed by coating the anti-corrosion treatment agent on only one side of the isolation layer 14, or the second anti-corrosion layer 13 can be formed by coating the anti-corrosion treatment agent on both sides of the isolation layer 14. Corrosion layer 15. In addition, when the second anti-corrosion layer 15 is provided, the second anti-corrosion layer 15 is preferably formed in a stage before the formation of the first adhesive layer 12 or the like, and is more preferably formed simultaneously with the first anti-corrosion layer 13.

In addition, when forming the first anti-corrosion layer 13 and the second anti-corrosion layer 15 at the same time, it is preferable to immerse the isolation layer 14 in an anti-corrosion treatment agent, make the anti-corrosion treatment agent adhere to both surfaces of the isolation layer 14, and then heat and dry it. .

Next, a first adhesive layer 12 is formed on the first anti-corrosion layer 13.

Specifically, a layer composed of the above-mentioned adhesive is formed on the surface of the stainless steel foil 14 on which the first anticorrosion layer 13 is provided, and is heated and dried as necessary.

When the adhesive is an adhesive for thermal lamination that does not contain an organic solvent, the components (A) and (B) are melt-kneaded to react the two components, and then applied to the first protective layer. The first adhesive layer 12 is formed by etching and drying the layer 13.

For the melt-kneading, conventional devices such as a single-screw extruder, a multi-screw extruder, a Bunbury mixer, a plastic mill (Plastmill), and a heated roll kneader can be used. In order to suppress the decomposition of epoxy groups during melt kneading, volatile components that can react with epoxy groups, such as moisture, are preferably removed from the device in advance, and when volatile components are generated during the reaction, they are discharged out of the device at any time by degassing. When the acid-modified polyolefin resin has an acid anhydride group as an acidic functional group, since it has high reactivity with an epoxy group and can react under more stable conditions, it is preferable. As far as the two components are fully melted without thermal decomposition, during melt kneading The heating temperature is preferably selected from the range of 240 to 300°C. In addition, the kneading temperature can be measured by a method such as contacting a thermocouple with a molten adhesive just extruded from the melt-kneading device.

In addition, when the adhesive is an adhesive for dry lamination containing an organic solvent, the components (A) and (B) are dissolved in the organic solvent, and then the solution is applied on the first anticorrosion layer 13 And dried to form the first adhesive layer 12. In addition, the formation of the first adhesive layer 12 may use a conventional dry layer together with the laminating step of the sealant layer 11 described later (or the laminating step of the second sealant layer 11' and the sealant layer 11). Jaeger and others are carried out in a series of steps.

After that, the sealant layer 11 or the second sealant layer 11' having the sealant layer 11 is placed in contact with the formed first adhesive layer 12, and the laminate is laminated. The lamination may be dry lamination or thermal lamination, but dry lamination at 70 to 150°C is preferred. The pressure during dry lamination is preferably 0.1 to 0.5 MPa.

Specifically, a film constituting the sealant layer 11 (and the second sealant layer 11') is prepared in advance, and the film is arranged on the first adhesive layer and then laminated. The temperature of the lamination is not particularly limited as long as it is a temperature at which the sealant layer 11 or the second sealant layer 11' and the first anticorrosion layer 13 and the isolation layer 14 are well bonded via the first adhesive layer. It is determined in consideration of the material or melting point of the adhesive constituting the first adhesive layer 12. The temperature during dry lamination is usually 70 to 150°C, preferably 80 to 120°C.

In addition, the step of forming the first adhesive layer 12 and the step of disposing the sealant layer 11 (and the second sealant layer 11') and performing (dry) lamination, It can be carried out in a series of steps using a conventional (dry-type) lamination device.

The method of forming the second anti-corrosion layer 15, the second adhesive layer 16, and the base layer 17 is not particularly limited. For example, the second adhesive layer 16 is formed on the base layer 17 in advance to form a double layer structure The layered body. After that, the two-layer laminate is made to have the sealant layer 11 (and the second sealant layer 11'), the first adhesive layer 12, the first anticorrosion layer 13, the isolation layer 14, and the second anticorrosion layer The laminate of 15 is dry-laminated so that the second adhesive layer 16 and the second anticorrosion layer 15 are in contact with each other, so that a laminate 10 for battery exterior packaging composed of eight layers can be prepared.

As mentioned above, one embodiment of the present invention has been described based on the battery exterior laminate 10 shown in FIG. 1. However, the technical scope of the present invention is not limited to the above-mentioned embodiment, and can be used without departing from the spirit of the present invention. Within the scope of, various changes were added.

In addition, it may also be on the side of the sealant layer 11 that is not in contact with the second sealant layer 11' or the first adhesive layer 12, or the side of the substrate layer 17 that is not in contact with the second adhesive layer 16, Set other layers to form a structure of nine or more layers.

In the laminate 10 for battery exterior packaging shown in Figure 1, the first anticorrosion layer 13 and the second anticorrosion layer 15 are formed on both sides of the separator layer 14. However, the battery exterior laminate is used In the battery exterior body of the body 10, the sealant layer 11 side is the inner surface side and can come into contact with the electrolyte or the like. Therefore, an anti-corrosion layer is formed at least on the sealant layer 11 side of the isolation layer 14. That is, it may be a structure in which the second anticorrosion layer 15 is omitted from the laminate 10 for battery exterior packaging in FIG. 1.

In the laminate 10 for battery exterior packaging shown in Figure 1, although the base layer 17 and the second adhesive layer 16 are in direct contact, the base layer 17 may be The inner surface side of the is provided with a printed layer for improving design.

The printing layer may have the same structure as the above-mentioned coating layer.

In the laminate 10 for battery exterior packaging shown in Fig. 1, the second sealant layer 11' is provided, but the second sealant layer 11' has an arbitrary structure, and this layer may be omitted. When the laminate 10 for battery exterior packaging of the present invention has only the sealant layer 11 as a layer having a sealing function, it can also have sufficient adhesive strength required for the battery exterior body after heat sealing.

Although the first adhesive layer 12 is provided in the laminate 10 for battery exterior packaging shown in FIG. 1, the first adhesive layer 12 may be omitted. When the first adhesive layer 12 is not provided, the single layer of the sealant layer 11 or the sealant layer 11 provided with the second sealant layer 11' is arranged on the isolation layer 14 provided with the first anticorrosive layer 13 Above, the laminated body is heated and laminated, so that the laminated body can be prepared without passing through the first adhesive layer 12.

〔Battery Outer Body〕

The battery exterior body of the second aspect of the present invention is a battery exterior body having the laminate for battery exterior of the first aspect, which has an internal space for accommodating the battery, and a sealant layer of the laminate for battery exterior The side is the side of the internal space. Specifically, it is obtained by molding the laminate for battery exterior packaging of the first aspect into a desired shape so that the sealant layer faces the internal space, and sealing the ends as necessary.

The shape and size of the battery exterior body are not particularly limited, and can be appropriately determined according to the type of battery used.

The battery exterior body may be composed of one component, or it may be formed by combining two or more components (such as the container body and the lid) as described later using Figure 2 to make.

[Preparation method of battery exterior body]

A method for manufacturing a battery exterior body according to a third aspect of the present invention is characterized by comprising the step of forming a step of pressing the battery in the first aspect from the sealant layer side of the laminate for battery exterior The laminated body for exterior packaging is the first member of the forming material to form a container body having a recessed portion; the assembling step is to combine the sealant layer of the container body with the laminated body for battery exterior packaging. The sealant layers of the second part of the forming material are combined in a superposed manner; and the joining step is to heat seal the superposed sealant layers to join one sealant layer to the other sealant layers . The temperature during the heat sealing is lower than the mp (A) and higher than the mp (B).

With regard to the manufacturing method of the third aspect, the case of manufacturing the battery exterior body 20 shown in FIGS. 2 to 3 will be described.

In the battery exterior body 20, a container body 30 composed of the battery exterior laminate 10 of the first aspect of the present invention is overlapped with a lid portion 33 composed of the battery exterior laminate 10, and the peripheral portion is heat sealed. 29 and formed.

First, using an appropriate mold and a press, the laminate 10 for a battery exterior body is stretched (stretched) to form the container body 30. At this time, the side facing the internal space (recessed portion) formed by the stretching process is the side of the sealant layer 11 of the battery exterior body 10.

Next, the obtained container body 30 and the lid portion 33 composed of the battery exterior laminate 10 are combined so that the sealant layers 11 overlap each other. For the container body 30, since the side facing the internal space is the side of the sealant layer 11, the sealant layer of the container body 30 and the flat lid are combined. The 33 sealant layer can define the internal space.

After that, the space between the overlapped sealant layers (that is, the flange portion 32 of the container body 30 and the peripheral edge portion 34 of the lid portion 33) is heated at a temperature higher than mp(A) and lower than mp(B). By welding and joining the sealant layers, the battery exterior body 20 as shown in Fig. 2 can be obtained. That is, in the battery shown in FIG. 3, by covering the lid portion 33 on the upper surface of the container body 30, the recessed portion 31 and the lid portion 33 can form an internal space for storing the battery.

The temperature (t) at the time of the thermal fusion connection is mp(A)<(t)<mp(B), preferably 125 to 155°C, more preferably 130 to 155°C, and still more preferably 135 to 155°C.

〔battery〕

The battery of the fourth aspect of the present invention includes the battery exterior body of the second aspect.

Examples of the battery include a secondary battery such as a lithium ion battery or a capacitor such as an electric double layer capacitor that uses an organic electrolyte in an electrolyte. Since the laminate for battery exterior packaging of the present invention has high electrolyte resistance, it is possible to obtain a battery that can work well even when an electrolyte containing LiPF ₆ or the like is used.

As an example, a perspective view of the secondary battery 40 is shown in FIG. 2. The secondary battery 40 is a battery in which a lithium ion battery 27 is enclosed in a battery exterior container 20.

In the battery exterior container 20, the container body 30 composed of the battery exterior laminate 10 of the first aspect of the present invention and the lid portion 33 composed of the battery exterior laminate 10 are stacked, and the peripheral portion is heat sealed 29 and formed. Reference numeral 28 is an electrode lead connected to the positive electrode and the negative electrode of the lithium ion battery 27.

The battery shown in Figure 2 can be prepared in the following manner.

First, as shown in (a) in Figure 3, the laminate 10 for battery exterior packaging is extruded from the sealant layer side of the laminate 10 for battery exterior packaging by stretch molding or the like and is molded to have a recess 31 In the shape of a tray, the container body 30 is obtained. The depth of the recess 31 may be 2 mm or more, for example.

A lithium ion battery (the lithium ion battery 27 in FIG. 2) is housed in the recess 31 of the container body 30.

Next, as shown in (b) in Figure 3, by overlapping the lid portion 33 composed of the battery exterior laminate 10 on the container body 30, the flange portion 32 and the lid portion of the container body 30 are heat-sealed The peripheral edge portion 34 of 33 obtains the secondary battery 40 as shown in FIG. 2. That is, in the battery shown in FIG. 3, by covering the lid portion 33 on the upper surface of the container main body 30, the recessed portion 31 and the lid portion 33 form an internal space for storing the battery.

In addition, the battery in the present invention can also be prepared in the following manner.

First, as shown in Fig. 4 (a), in the rectangular battery exterior laminate 50, the length is extruded from the sealant layer side of the battery exterior laminate 50 by stretch molding or the like A part of the one end side in the direction is molded, thereby obtaining a molded body 55 having a recess 51. The depth of the recess 51 may be, for example, 2 mm or more.

Next, although not shown in the drawings, a lithium ion battery (lithium ion battery 27 in FIG. 2) is accommodated in the recess 51 of the molded body 55.

Next, on the other end side of the molded body 55 where the recess 51 is not formed In a part of, the fold line L extending in the width direction of the molded body 55 is folded toward the sealant layer side. At this time, in the molded body 55, with respect to the folding line L, the area on the side of the recess 51 is referred to as the "first area 551"; with respect to the folding line L, the area on the opposite side of the recess 51 is referred to as the "second area" 552".

Next, the sealant layer on the periphery 52 of the recess 51 in the first region 551 and the sealant layer (peripheral edge portion 54) overlapping with the periphery 52 in the second region 552 are overlapped. As a result, the second area 552 overlaps the recess 51 of the first area 551.

Next, as shown in (b) in Figure 4, by heat-sealing the sealant layer around the recess 51 and the sealant layer in the second region 552, a secondary battery exterior body composed of one component can be obtained. Battery 60. That is, in the battery shown in (b) in FIG. 4, by covering the upper surface of the recess 51 with the second region 552, the recess 51 and the second region 552 can form an internal space for storing the battery.

Example

Hereinafter, the present invention will be described in further detail through examples, but the present invention is not limited to these examples.

[Examples 1 to 11, Comparative Examples 1 to 5]

<Examples 1 to 8, Comparative Examples 1 to 5>

First, the metal foil shown in Table 1 was prepared. The metal foil was coated with an anti-corrosion treatment agent on both sides and heated and dried in an oven at 200° C. to form a first anti-corrosion layer and a second anti-corrosion layer with a thickness of 0.1 μm on both sides. Use an anti-corrosion treatment agent mixed with chromium fluoride, phosphoric acid, and polyvinyl alcohol.

Then, coating the first adhesive on the formed first anti-corrosion layer To form a first adhesive layer with a thickness of 3 μm. The first adhesive is obtained by the following method: 90% by mass of maleic anhydride modified polypropylene and 10% by mass of novolac epoxy resin with bisphenol A structure (manufactured by Mitsubishi Chemical Corporation, trade name: jER157S70, viscosity=80, epoxy equivalent=210), is obtained by melting and kneading in toluene for 10 minutes at room temperature with a solid content of 10%, and then stirring and dissolving.

Thereafter, by dry lamination at 100° C., the sealing film obtained using the sealant layer composition shown in Table 1 and the first adhesive layer in the laminate obtained above were laminated.

In addition, by coating a second adhesive composed of a polyurethane-based adhesive on a substrate layer composed of a biaxially stretched polyamide (nylon) resin film with a thickness of 6 μm and a thickness of 25 μm. The agent layer (thickness of 3 μm) is formed.

This second adhesive layer was opposed to the second anticorrosive layer in the laminate obtained above, and was laminated by dry lamination at 80°C to obtain a laminate for battery exterior packaging.

<Example 9>

Except that the following adhesive was used as the first adhesive, a laminate for battery exterior packaging was obtained in the same manner as in Examples 1 to 8. The adhesive was 90% by mass maleic anhydride Modified polypropylene, and 10% by mass "MODIPER A4100" (trade name; manufactured by NOF Corporation; ethylene-glycidyl methacrylate copolymer, graft polymer with polystyrene; relative to the main chain All monomers, the ratio of glycidyl methacrylate monomer = 30% by mass) is an adhesive made by melt mixing.

<Example 10>

Except that the following adhesive was used as the first adhesive, a laminate for battery exterior packaging was obtained in the same manner as in Examples 1 to 8. The adhesive was 90% by mass maleic anhydride Modified polypropylene and 10% by mass of "EPOCROS RPS-1005" (trade name, manufactured by Nippon Shokubai Co., Ltd.) (resin obtained by copolymerizing styrene and 2-isopropenyl-2-oxazoline; number average Molecular weight = 70,000) An adhesive made of melt-mixing.

In Table 1, each abbreviation has the following meaning. The value in [] is the addition amount (parts by mass).

A-1: Block polypropylene (melting point 162°C)

A-2: Block polypropylene (melting point 135℃)

B-1: Atactic polypropylene (melting point 140℃)

B-2: Atactic polypropylene (melting point 130℃)

B-3: Atactic polypropylene (melting point 120℃)

C-1: Olefin elastomer (melting point 130℃)

C-2: Olefin elastomer (melting point 80℃)

C-3: Olefin elastomer (melting point 120℃)

AL: Aluminum foil

SUS: stainless steel foil

(Heat resistance test)

The laminates for battery exterior packaging prepared in the above examples were heat-sealed at 0.3MPa‧150℃‧2 seconds, T-peeled at 23℃, and evaluated based on the following criteria. The result was “heat resistance” Shown in Table 1.

A: Above 50N/15mm

B: Less than 50N/15mm, more than 40N/15mm

C: Less than 40N/15mm, more than 30N/15mm

D: Less than 30N/15mm

(Low temperature sealing test)

The laminates for battery exterior packaging prepared in each of the above examples were heat-sealed at 0.3MPa‧140℃‧3 seconds, T-peeled at 23℃, and evaluated based on the following criteria. The result was “low temperature sealability” ”Is shown in Table 1.

○: 40N/15mm or more

×: less than 40N/15mm

(Cold resistance test)

After heat-sealing the laminates for battery exteriors prepared in the above examples at 0.3MPa‧155℃‧3 seconds, T-peeling was performed at -30℃, and the evaluation was carried out according to the following criteria.性" is shown in Table 1.

A: 40N/15mm or more

B: Less than 40N/15mm, more than 20N/15mm

C: Less than 20N/15mm

(Thermal shock test)

Heat-sealing the laminates for battery exteriors prepared in the above examples at 0.3MPa‧155℃‧3 seconds. After that, 60 minutes at 80°C and 60 minutes at -30°C were regarded as one cycle, and a thermal shock experiment was performed in which this cycle was repeated 100 times. The appearance of the laminate for battery exterior after the thermal shock test was visually observed, and the T-shaped peel strength was measured under conditions of 15 mm width, 300 mm/min, and 180-degree peeling. The evaluation was performed based on the following criteria, and the results are shown in Table 1 as "thermal shock test resistance".

A: When visually confirming the appearance, no discoloration of the sealant layer was found, and the T-shaped peel strength did not change compared to before the thermal shock test

B: When visually confirming the appearance, the sealant layer was partially discolored, but the T-shaped peel strength did not change compared to before the thermal shock test

C: When visually confirming the appearance, it was found that the sealant layer was partially discolored. In addition, the T-shaped peeling strength was increased compared to before the thermal shock test, and the peeling was easily deteriorated.

From the results shown in Table 1, it can be confirmed that Examples 1 to 11 using the laminates for battery exterior packaging of the present invention have superior durability under various conditions compared to Comparative Examples 1 to 6 ( Adhesiveness), and the good adhesiveness can also be obtained when heat-sealing is performed at a lower temperature.

[Example 11]

In the same manner as in Example 2 described above, a laminate for battery exterior packaging was obtained.

[Examples 12~13]

As the above-mentioned sealing film, except for using a double-layer sealing film having a sealing agent layer 11 and a second sealing agent layer 11', in the same manner as in Examples 1 to 8 described above, a laminate for battery exterior packaging was obtained.

Specifically, as the outermost (innermost) sealant layer corresponding to the sealant layer 11, a composition having the same composition as the sealant layer of Example 2 was used. In addition, as the inner sealant layer corresponding to the second sealant layer 11', a composition having the composition shown in Table 2 was used. A double-layer sealing film was prepared by co-extruding these two compositions. After that, using the double-layer sealing film, the second sealing agent layer and the first adhesive layer of the sealing film were laminated by dry lamination.

(Sealing strength)

The laminates for battery exterior packaging prepared in the above examples were heat-sealed at 0.4MPa‧155℃‧3 seconds, T-peeled at 23℃, and evaluated based on the following criteria. The result was "sealing strength" Shown in Table 2.

A: 40N/15mm or more

B: Less than 40N/15mm

From the results shown in Table 2, it can be confirmed that by having the second secret The sealing agent layer can further improve the sealing strength.

10‧‧‧Laminated body

11‧‧‧Sealant layer

11’‧‧‧Second sealant layer

12‧‧‧The first adhesive layer

13‧‧‧The first anti-corrosion layer

14‧‧‧Isolation layer (metal foil)

15‧‧‧Second anti-corrosion layer

16‧‧‧Second Adhesive Layer

17‧‧‧Substrate layer

Claims (11)

A laminate for battery exterior packaging, which is formed by having at least a sealant layer, a first adhesive layer, a separator layer composed of metal foil, and a substrate layer in this order, characterized in that the sealant layer It is composed of block polypropylene, random polypropylene, and olefin elastomer. The content ratios of block polypropylene, random polypropylene, and olefin elastomer are A, B, and C respectively in order of mass ratio. When the melting points of segment polypropylene, random polypropylene, and olefin elastomer are mp(A), mp(B), mp(C), respectively, the sealant layer satisfies the following formulas (1)~(4) Relationship: A>B (1) A>C (2) A+B+C=100 (3) mp(A)>mp(B)≧mp(C) (4). The laminate for battery exterior packaging described in the first item of the scope of patent application, wherein, in the sealant layer, the content of block polypropylene is 35 to 80% by mass, and the content of random polypropylene is 10 to 45% by mass, and the content ratio of the olefin elastomer is 10 to 40% by mass. The laminate for battery exterior packaging as described in item 1 or 2 of the scope of patent application, wherein a second sealant layer is further provided between the sealant layer and the first adhesive layer. The laminate for battery exterior packaging according to item 1 or 2 of the scope of patent application, wherein the first adhesive layer contains maleic acid-modified polypropylene and an epoxy group or oxazoline group Compound. The laminate for battery exterior packaging described in item 4 of the scope of patent application, wherein the compound having an epoxy group is a phenol novolac type epoxy resin or an epoxy group-containing polyolefin resin . The laminate for battery exterior packaging as described in item 4 of the patent application, wherein the compound having an oxazoline group is an oxazoline group-containing styrene resin. A battery exterior body having the laminated body for battery exterior as described in any one of items 1 to 6 of the scope of patent application, characterized in that it has an internal space for accommodating the battery, and the laminated body for battery exterior The side of the sealant layer is the side of the internal space. A method for preparing a battery exterior body, which is characterized by comprising: a molding step including: using the battery exterior laminate body described in any one of items 1 to 6 in the scope of the patent application as a forming material The first member is pressed from the sealant layer side of the laminate for battery exterior packaging to form a container body having a recess; an assembling step including: making the sealant layer of the container body, Combined with the sealant layer of the second member made of the battery exterior laminate as a forming material in a superposed manner; and a joining step including: making one of the superposed sealant layers Thermally fusion connection between them to join one sealant layer and another sealant layer. A method for preparing a battery exterior body, which is characterized by comprising: a molding step including: using the battery exterior laminate body described in any one of items 1 to 6 in the scope of the patent application as a forming material A part of the component is pressed from the sealant layer side of the laminate for battery exterior packaging to form a recess; The assembling step includes: folding the component toward the sealant layer side in a region where the recess is not formed, and setting the formed fold line as the first region of the recess in the side of the recess The peripheral sealant layer overlaps with the sealant layer in the second region on the opposite side of the recess with respect to the fold line; and a joining step including: sealing the overlapped The agent layers are thermally fused to join one sealant layer with another sealant layer. According to the method for preparing the battery exterior body described in item 8 or 9 of the scope of the patent application, the temperature during the thermal fusion connection is lower than the mp(A) and higher than the mp(B). A battery characterized by having the battery exterior body as described in item 7 of the scope of patent application.

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