WO2018194176A1

WO2018194176A1 - Packaging material for batteries, method for producing same, and battery

Info

Publication number: WO2018194176A1
Application number: PCT/JP2018/016367
Authority: WO
Inventors: かおる津森; 山下　孝典; 山下　力也
Original assignee: 大日本印刷株式会社
Priority date: 2017-04-20
Filing date: 2018-04-20
Publication date: 2018-10-25
Also published as: JP6525119B2; CN110537266B; JPWO2018194176A1; CN110537266A

Abstract

Provided is a packaging material for batteries, which is capable of effectively suppressing deterioration of the characteristics of the outer surface of the packaging material for batteries during a process for producing a battery or the packaging material for batteries. A packaging material for batteries according to the present invention is configured from a laminate which sequentially comprises at least a resin layer, a bonding layer, a base material layer, a barrier layer and a thermally fusible resin layer in this order. The bonding layer contains a polyester resin; and the resin layer is able to be separated from the laminate with use of an aqueous liquid.

Description

Battery packaging material, manufacturing method thereof, and battery

The present invention relates to a packaging material for a battery, a manufacturing method thereof, and a battery.

Conventionally, various types of batteries have been developed. In these batteries, a battery element composed of an electrode, an electrolyte and the like needs to be sealed with a packaging material or the like. Metal packaging materials are frequently used as battery packaging materials.

In recent years, batteries having various shapes have been demanded with the improvement in performance of electric vehicles, hybrid electric vehicles, personal computers, cameras, mobile phones and the like. The battery is also required to be thin and light. However, it is difficult to follow the diversification of battery shapes with metal packaging materials that have been widely used in the past. Further, since it is made of metal, there is a limit to reducing the weight of the packaging material.

Therefore, as a battery packaging material that can be easily processed into various shapes and can be made thinner and lighter, there is a film-like laminate in which a base material layer / barrier layer / heat-sealable resin layer are sequentially laminated. Proposed.

In such a film-shaped battery packaging material, generally, a concave portion is formed by molding, and a battery element such as an electrode or an electrolytic solution is arranged in the space formed by the concave portion, and a heat-fusible resin layer A battery in which the battery element is accommodated in the battery packaging material is obtained by heat-sealing them together.

In the process of manufacturing a battery packaging material formed by such a film-like laminate, and the process of manufacturing a battery using the battery packaging material, the battery is transported until the battery is completed. Surface characteristics on the base material layer side may be deteriorated, such as scratches, heat deterioration during heat fusion, and adhesion of the electrolyte when encapsulating the electrolyte. Since the surface on the base material layer side is located outside the battery, it is required to avoid such characteristic deterioration as much as possible.

For example, Patent Document 1 discloses a protective film characterized in that the adhesive strength is almost eliminated by heating or ultraviolet irradiation in advance for a laminated film having a three-layer structure in which a protective layer and a heat sealing layer are laminated on a metal foil. A method has been proposed in which a battery is manufactured after affixing, and a protective film having a reduced adhesive strength is peeled off by applying heat or ultraviolet light.

However, the method described in Patent Document 1 has a problem that a layer or the like located under the protective film is deteriorated by heating or ultraviolet irradiation. In addition, it is necessary to set the heating temperature and the wavelength of ultraviolet rays, and there is also a problem that the adhesive force of the protective film does not become constant because these set values change.

JP 2009-43442 A

The present invention is an invention made in view of such problems of the prior art. That is, the main object is to provide a battery packaging material that can effectively suppress deterioration of characteristics of the outer surface of the battery packaging material in the process of manufacturing the battery or the battery packaging material. Furthermore, another object of the present invention is to provide a method for producing the battery packaging material, a battery using the battery packaging material, and a method for producing the battery.

The present inventors have intensively studied to solve the above problems. As a result, it is composed of a laminate including at least a resin layer, a bonding layer, a base material layer, a barrier layer, and a heat-fusible resin layer in this order, the bonding layer includes a polyester resin, The battery packaging material that can be peeled off from the laminate using an aqueous liquid does not require heating, ultraviolet irradiation, or the like that deteriorates the characteristics of the outer surface of the battery packaging material as in Patent Document 1, and is used for batteries or batteries. It has been found that the characteristic deterioration of the outer surface of the battery packaging material in the process of producing the packaging material can be effectively suppressed.
The present invention has been completed by further studies based on these findings.

That is, this invention provides the invention of the aspect hung up below.
Item 1. At least, it is composed of a laminate comprising a resin layer, a bonding layer, a base material layer, a barrier layer, and a heat-fusible resin layer in this order,
The bonding layer includes a polyester resin,
The battery packaging material, wherein the resin layer is peelable from the laminate using an aqueous liquid.
Item 2. In an environment of a temperature of 25 ° C., a relative humidity of 50%, and atmospheric pressure, the peel strength when the resin layer is peeled from the laminate without water adhering to the bonding layer is 2.0 N / 15 mm or more. ,And,
The peel strength when peeling the resin layer from the laminate using the aqueous liquid in an environment of temperature 25 ° C., relative humidity 50%, and atmospheric pressure is 1.0 N / 15 mm or less,
Item 2. The battery packaging material according to Item 1, wherein the aqueous liquid is water.
Item 3. Item 3. The battery packaging material according to

Item

1 or 2, wherein a lubricant is present on the surface of the laminate on the resin layer side.
Item 4. Item 4. The battery packaging material according to any one of Items 1 to 3, wherein an ultraviolet absorber is contained in at least one of the resin layer, the bonding layer, and the base material layer.
Item 5. Item 5. The battery packaging material according to Item 4, wherein the ultraviolet absorber is a benzotriazole-based ultraviolet absorber.
Item 6. Item 6. The battery packaging material according to any one of Items 1 to 5, wherein a light stabilizer is contained in at least one of the resin layer, the bonding layer, and the base material layer.
Item 7. Item 7. The battery packaging material according to Item 6, wherein the light stabilizer is a hindered amine light stabilizer.
Item 8. At least a step of obtaining a laminate by laminating a resin layer, a bonding layer, a base material layer, a barrier layer, and a heat-fusible resin layer in this order;
The manufacturing method of the packaging material for batteries using the said joining layer contains the polyester resin and the said resin layer can peel from the said laminated body using an aqueous liquid.
Item 9. A battery in which a battery element including at least a positive electrode, a negative electrode, and an electrolyte is accommodated in a package formed of the battery packaging material according to any one of Items 1 to 7.
Item 10. At least, the use of a laminate comprising a resin layer, a bonding layer, a base material layer, a barrier layer, and a heat-fusible resin layer in this order for a battery packaging material,
The bonding layer includes a polyester resin,
Use of the laminate for battery packaging materials, wherein the resin layer is peelable from the laminate using an aqueous liquid.

According to the present invention, it is possible to provide a battery packaging material that can effectively suppress the deterioration of characteristics of the outer surface of the battery packaging material in the process of manufacturing the battery or the battery packaging material. Moreover, according to this invention, the manufacturing method of the said packaging material for batteries, the battery using the said packaging material for batteries, and the manufacturing method of the said battery can also be provided.

It is a schematic diagram which shows an example of the cross-sectional structure of the packaging material for batteries of this invention. It is a schematic diagram which shows an example of the cross-sectional structure of the packaging material for batteries of this invention. It is a schematic diagram which shows an example of the cross-sectional structure of the packaging material for batteries of this invention. It is a schematic diagram for demonstrating the measuring method of peeling strength.

The battery packaging material of the present invention is composed of a laminate including at least a resin layer, a bonding layer, a base material layer, a barrier layer, and a heat-fusible resin layer in this order. The resin layer is characterized in that the resin layer can be peeled off from the laminate using an aqueous liquid. Hereinafter, the battery packaging material of the present invention, the battery using the battery packaging material, and the manufacturing method thereof will be described in detail with reference to FIGS. 1 to 3.

In this specification, the numerical range indicated by “to” means “above” or “below”. For example, the notation of 2 to 15 mm means 2 mm or more and 15 mm or less.

1. Laminated structure and physical properties of battery packaging material The battery packaging material of the present invention comprises at least a resin layer 1a, a bonding layer 1b, a base material layer 2, a barrier layer 3, and a heat as shown in FIGS. It is comprised from the laminated body which has the fusible resin layer 4 in this order. In the battery packaging material of the present invention, the resin layer 1a is the outermost layer, and the heat-fusible resin layer 4 is the innermost layer. That is, when the battery is assembled, the battery element is sealed by heat-sealing the heat-fusible resin layers 4 positioned at the periphery of the battery element to seal the battery element.

1 to 3 show a mode in which a laminate of a resin layer 1a and a bonding layer 1b containing a polyester resin constitutes the protective layer 1. FIG. The bonding layer 1b is provided for bonding (more specifically, sticking) the resin layer 1a to another layer. The bonding layer 1b can be referred to as an adhesive layer.

In the battery packaging material 10 of the present invention, as shown in FIGS. 2 and 3, an adhesive layer is formed between the base material layer 2 and the barrier layer 3 as necessary for the purpose of enhancing the adhesion between them. 5 may be provided. In addition, as shown in FIG. 3, the battery packaging material 10 of the present invention is bonded between the barrier layer 3 and the heat-fusible resin layer 4 as necessary for the purpose of improving the adhesion between them. A layer 6 may be provided. Moreover, although illustration is abbreviate | omitted, between the joining layer 1b and the base material layer 2, the surface coating layer may be provided.

As will be described later, the resin layer 1a can be peeled off from the laminate constituting the battery packaging material 10 using an aqueous liquid. This is because the bonding layer 1b has adhesiveness due to the polyester resin. In the battery packaging material of the present invention, the resin layer 1a can be easily peeled from the laminate constituting the battery packaging material 10 using an aqueous liquid. Further, peeling using an aqueous liquid has little effect on the base material layer 2 and the surface coating layer, and even if the base material layer 2 absorbs moisture, it only needs to be dried. Can be suppressed.

In the present invention, the term “adhesiveness” or “adhesiveness” means a property of joining a plurality of objects, and is a concept included in a broad sense of adhesion, and is a sticking property (tackiness). Further, the aqueous liquid is not particularly limited as long as it is a liquid containing water, but specific examples of the aqueous liquid include water, a hydrous polar organic solvent, and the like. Examples of the hydrous polar organic solvent include aqueous solutions of polar organic solvents such as alcohol, acetone, ethyl acetate, and dimethyl ether. Examples of the aqueous solution of alcohol (hydrous alcohol) include aqueous solutions of lower alcohols such as methanol and ethanol. The mass ratio of water to the polar solvent (water: polar solvent) in the hydrous polar organic solvent is about 100: 1 to 100: 100. The aqueous liquid may be constituted by one type of liquid or may be constituted by two or more types of liquids.

In the present invention, the fact that the resin layer 1a can be peeled from the laminate means that the resin layer 1a can be peeled from the layer in contact with the bonding layer 1b. The bonding layer 1b may be peeled off from the surface on the base material layer 2 side together with the resin layer 1a, and the components of the bonding layer 1b may remain on the surface on the base material layer 2 side.

The upper limit of the peel strength (A) of the resin layer 1a when water is adhered to the bonding layer 1b in an environment of temperature 25 ° C., relative humidity 50%, and atmospheric pressure (1 atm) is preferably about 1.0 N. / 15 mm or less, more preferably about 0.5 N / 15 mm or less, although there is no particular lower limit, preferably about 0.0 N / 15 mm or more, more preferably about 0.01 N / 15 mm or more, and still more preferably about 0.1 N / 15 mm or more is mentioned. The range of the peel strength (A) is preferably about 0.0 to 1.0 N / 15 mm, about 0.0 to 0.5 N / 15 mm, about 0.01 to 1.0 N / 15 mm, 0.01 ˜0.5 N / 15 mm, 0.1˜1.0 N / 15 mm, and 0.1˜0.5 N / 15 mm. In the present invention, “releasable from the laminate using an aqueous liquid” means, for example, that the resin layer 1a can be easily peeled from the laminate using an aqueous liquid. Strength (A) satisfies the above value.

The lower limit of the peel strength (B) of the resin layer 1a when water is not adhered to the bonding layer 1b in an environment of a temperature of 25 ° C., a relative humidity of 50%, and atmospheric pressure (1 atm) is preferably about 2. 0 N / 15 mm or more, more preferably about 2.2 N / 15 mm or more, and there is no particular upper limit, but preferably about 30.0 N / 15 mm or less. The range of the peel strength (B) is preferably about 2.0 to 30.0 N / 15 mm, more preferably about 2.2 to 30.0 N / 15 mm.

In the battery packaging material of the present invention, the peel strength (B) of the resin layer 1a when water does not adhere to the bonding layer 1b is about 2.0 N / 15 mm or more, and water adheres to the bonding layer 1b. The peel strength (A) of the resin layer 1a in the case of being made is preferably about 1.0 N / 15 mm or less, the peel strength (B) is about 2.2 N / 15 mm or more, and the peel strength More preferably, (A) is about 0.5 N / 15 mm or less.

In the battery packaging material of the present invention, the resin layer 1a has high peel strength before water adheres to the bonding layer 1b, and the battery is used as the outermost layer of the laminate constituting the battery packaging material. The characteristic deterioration of the packaging material is suitably suppressed, and the peel strength of the resin layer 1a is reduced by attaching an aqueous liquid to the bonding layer 1b at a desired timing. More specifically, when water adheres to the bonding layer 1b, moisture penetrates into at least one of the resin layer 1a, the bonding layer 1b, and the base material layer 2, and the adhesive strength of the bonding layer 1b decreases. The peel strength of the resin layer 1a is reduced. Thereby, the resin layer 1a can be suitably peeled from the laminated body. For example, printing may be performed on the outside of the battery from the viewpoint of battery identification. In the battery packaging material of the present invention, until printing is performed, the deterioration of the characteristics of the surface of the battery packaging material on the substrate layer 2 side is effectively suppressed, and an aqueous liquid is used when printing is performed. By peeling off the resin layer 1a from the laminate, the surface of the battery packaging material that becomes the printing surface can be easily exposed, and the surface of the base material layer 2 or the surface coating layer can be exposed to ink. It can also be suitably applied to applications where printing is performed. Further, after the battery packaging material of the present invention including the resin layer 1a is subjected to molding by a mold, the resin layer 1a is peeled off from the laminate using an aqueous liquid, so that the resin layer 1a becomes a pin of the barrier layer 3 There is an effect of suppressing holes and an effect of suppressing the surface of the base material layer 2 and the surface coating layer from being damaged by the mold, and the effect of improving moldability can be suitably enjoyed. Further, when the heat-fusible resin layer 4 is heat-sealed using the battery packaging material of the present invention having the resin layer 1a, the deterioration of the base material layer 2 and the surface coating layer due to high temperature and high pressure is caused by the resin layer. It can suppress effectively by the protection by 1a. Moreover, when using for the battery by which heat dissipation is calculated | required, or when using for the battery by which thinness is calculated | required, the resin layer 1a can be peeled and used. Note that the timing and purpose of peeling the resin layer 1a are not limited to these.

Specifically, the method for measuring the peel strength of the resin layer 1a in an environment of a temperature of 25 ° C., a relative humidity of 50%, and an atmospheric pressure (1 atm) is as follows.

<Method of measuring peel strength with water attached>
The battery packaging material is cut into a rectangular shape of 100 mm (MD: Machine Direction) × 15 mm (TD: Transverse Direction) to obtain a test sample. In an environment of a temperature of 25 ° C., a relative humidity of 50%, and an atmospheric pressure (1 atm), first, 35% hydrochloric acid is attached to the end portions of the resin layer 1a and the bonding layer 1b of the test sample, and is shown in the schematic diagram of FIG. As shown, the resin layer 1a is peeled off about 30 mm in the MD direction. The hydrochloric acid adhering to the test sample is wiped off and dried as it is. Next, water (W) is made to adhere to the part from which the resin layer 1a has been peeled off (the bonding layer 1b between the resin layer 1a and the base layer 2 side surface) using a dropper. At this time, water (W) is adhered to the entire boundary in the TD direction at the boundary between the resin layer 1a and the surface of the base material layer 2 side. The water is used in such an amount that the water adheres sufficiently throughout the TD direction at the boundary portion. Next, using a tensile tester (for example, an autograph manufactured by Shimadzu Corporation), the resin layer 1a is removed from the surface of the base material layer 2 side under the measurement conditions of a distance between chucks of 50 mm, a peeling speed of 50 mm / min, and a peeling angle of 180 °. The peel strength when the distance between chucks reaches 57 mm is defined as the peel strength (N / 15 mm) with water attached.

<Measurement of peel strength without water adhering>
In the state where <water is attached to the portion where the resin layer 1a is peeled off (bonding layer 1b between the resin layer 1a and the surface of the base material layer 2 side), except that water is not attached using a dropper. The peel strength when the resin layer 1a is peeled from the surface of the base material layer 2 side under the same measurement conditions as in the above, and when the distance between chucks reaches 57 mm, the peel strength in a state where water is not attached. (N / 15 mm).

The thickness of the laminate constituting the battery packaging material 10 of the present invention is not particularly limited, but the battery packaging material is excellent in moldability while reducing the thickness of the battery packaging material to increase the energy density of the battery. From the viewpoint of, for example, 180 μm or less, preferably 150 μm or less, more preferably about 60 to 180 μm, and still more preferably about 60 to 150 μm.

2. Each layer forming the battery packaging material [resin layer 1a and bonding layer 1b]
In the battery packaging material of the present invention, the resin layer 1a is located in the outermost layer of the battery packaging material, and can be peeled from the laminate constituting the battery packaging material using an aqueous liquid at a desired timing. Is a layer.

As shown in the schematic diagrams of FIGS. 1 to 3, the resin layer 1a is preferably laminated with a single bonding layer 1b to form a protective layer 1 having a two-layer structure.

The bonding layer 1b is adhered to the base material layer 2 (a surface coating layer when a surface coating layer described later is present). The resin layer 1a is located on the outermost layer side.

As described above, until the battery is completed, the battery packaging material or the battery is damaged during transportation, the heat deterioration during heat fusion, the adhesion of the electrolyte when encapsulating the electrolyte, etc. The surface characteristics of the packaging material for the base material layer 2 may be deteriorated, and such characteristic deterioration is required to be avoided as much as possible.

In the battery packaging material of the present invention, since the specific resin layer 1a and the bonding layer 1b that can be peeled are provided, in the process of manufacturing the battery or the battery packaging material, the battery packaging as in Patent Document 1 is provided. Heating, ultraviolet irradiation, or the like that deteriorates the characteristics of the outer surface of the material is unnecessary, and the deterioration of the characteristics of the outer surface of the battery packaging material can be effectively suppressed.

The bonding layer 1b contains a polyester resin. Moreover, it is preferable that the joining layer 1b is a thermoplastic resin. The fact that the bonding layer 1b is a thermoplastic resin means that, for example, in measuring the displacement of the probe using thermomechanical analysis, a probe is placed on the surface of the bonding layer 1b at the end of the battery packaging material (laminate) and measured. When the probe is heated from 40 ° C. to 250 ° C. under the conditions that the deflection setting of the probe at the start is −4 V and the heating rate is 5 ° C./min, the probe position is lower than the initial value. Can be confirmed. The details of the probe displacement measurement using thermomechanical analysis are the same as the method described in the resin layer 1a described later. Moreover, it can confirm that the joining layer 1b contains the polyester resin, for example by infrared spectroscopy.

The polyester resin contained in the bonding layer 1b is not particularly limited as long as the bonding layer 1b can be peeled and adhered to a layer adjacent to the bonding layer 1b by contacting the aqueous liquid. Until the bonding layer 1b comes into contact with the aqueous liquid, it adheres firmly to the layer adjacent to the bonding layer 1b, and easily peels off from the layer adjacent to the bonding layer 1b when the bonding layer 1b comes into contact with the aqueous liquid. From the viewpoint of enabling, a polyester elastomer is preferable as a specific example of the polyester resin. Since the polyester elastomer is polyester, the heat resistance is good. Further, since the polyester elastomer is polyester, the polarity is high and the wettability of the aqueous liquid is good, and it is easy to peel off using the aqueous liquid. Elastomers have many low molecular weight components and are easy to peel off. In addition, when the resin layer contains a polyester resin, the polyester elastomer has good adhesion to the polyester base material. Therefore, when the resin layer is peeled off, the bonding layer is peeled off together with the resin layer, and the base material layer 2 side. This is preferable because the components of the bonding layer hardly remain. The polyester elastomer is not particularly limited, but is preferably a saturated polyester elastomer, and more preferably a saturated polyester elastomer containing a polyalkylene ether glycol segment. As the saturated polyester-based elastomer containing a polyalkylene ether glycol segment, for example, a block copolymer composed of an aromatic polyester as a hard segment and a polyalkylene ether glycol or an aliphatic polyester as a soft segment is preferable. Furthermore, the polyester polyether block copolymer which has polyalkylene ether glycol as a soft segment is more preferable.

The polyester polyether block copolymer includes (i) an aliphatic and / or alicyclic diol having 2 to 12 carbon atoms, and (ii) an aromatic dicarboxylic acid or an alkyl ester thereof and / or an aliphatic dicarboxylic acid or The alkyl ester and (iii) polyalkylene ether glycol are used as raw materials, and those obtained by polycondensing oligomers obtained by esterification reaction or transesterification reaction are preferred. In addition, it can confirm that the joining layer 1b contains an elastomer, for example by having tack property (viscosity) at normal temperature.

As the aliphatic and / or alicyclic diol having 2 to 12 carbon atoms, for example, those generally used as a raw material for polyester, particularly as a raw material for polyester elastomer, can be used. Specific examples include ethylene glycol, propylene glycol, trimethylene glycol, 1,4-butanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol and the like. Among these, 1,4-butanediol or ethylene glycol is preferable, and 1,4-butanediol is particularly preferable. These diols may be used alone or in combination of two or more.

As the aromatic dicarboxylic acid, those generally used as raw materials for polyester, particularly polyester-based elastomers, can be used. Specific examples include terephthalic acid, isophthalic acid, phthalic acid, and 2,6-naphthalenedicarboxylic acid. Among these, terephthalic acid or 2,6-naphthalenedicarboxylic acid is preferable, and terephthalic acid is particularly preferable. These aromatic dicarboxylic acids may be used alone or in combination of two or more.

Examples of the alkyl ester of aromatic dicarboxylic acid include dimethyl ester and diethyl ester of aromatic dicarboxylic acid. Among these, dimethyl terephthalate and 2,6-dimethyl naphthalene dicarboxylate are preferable.

As the aliphatic dicarboxylic acid, cyclohexane dicarboxylic acid and the like are preferable, and as the alkyl ester, dimethyl ester and diethyl ester are preferable. In addition to the above components, a small amount of a trifunctional alcohol, tricarboxylic acid or an ester thereof may be copolymerized, and an aliphatic dicarboxylic acid such as adipic acid or a dialkyl ester thereof may be used as a copolymerization component.

Examples of the polyalkylene ether glycol include polyethylene glycol, poly (1,2- and / or 1,3-propylene ether) glycol, poly (tetramethylene ether) glycol compound, poly (hexamethylene ether) glycol compound, etc. Is mentioned. Of these, poly (tetramethylene ether) glycol compounds are preferred. The poly (tetramethylene ether) glycol-based compound includes poly (tetramethylene ether) glycol and its related compounds. The poly (hexamethylene ether) glycol-based compound includes poly (hexamethylene ether) glycol and its related compounds.

The preferable lower limit of the number average molecular weight of the polyalkylene ether glycol is about 400 or more, and the preferable upper limit is about 6000 or less. By setting the lower limit to about 400 or more, the block property of the copolymer is increased, and by setting the upper limit to about 6000 or less, phase separation in the system hardly occurs and polymer physical properties are easily developed. A more preferred lower limit is about 500 or more, a more preferred upper limit is about 4000 or less, a still more preferred lower limit is about 600 or more, and a still more preferred upper limit is about 3000 or less.

In addition, in this specification, a number average molecular weight means what was measured by the gel permeation chromatography (GPC). In addition, the measurement of the number average molecular weight by GPC is a standard polymer (polystyrene) conversion molecular weight.

When a polyester polyether block copolymer composed of polyester and polyalkylene ether glycol is used as the polyester elastomer, the lower limit of the content of the polyalkylene ether glycol component is preferably about 5% by mass or more, more preferably About 30 mass% or more, More preferably, about 55 mass% or more is mentioned, Preferably an upper limit becomes like this. Preferably about 90 mass% or less, More preferably, about 80 mass% or less is mentioned. The content of the polyalkylene ether glycol component can be calculated using nuclear magnetic resonance spectroscopy (H ¹ -NMR measurement) based on the chemical shift of the hydrogen atom and its integrated value.

The polyester elastomer is preferably a modified polyester elastomer modified with a modifier. The modification reaction for obtaining the modified polyester elastomer is carried out, for example, by reacting the polyester elastomer with an α, β-ethylenically unsaturated carboxylic acid as a modifier. In the modification reaction, it is preferable to use a radical generator. In the modification reaction, a graft reaction in which an α, β-ethylenically unsaturated carboxylic acid or a derivative thereof is added to a polyester elastomer mainly occurs, but a decomposition reaction also occurs. As a result, the modified polyester elastomer may have a lower molecular weight and a lower melt viscosity. Further, in the modification reaction, it is considered that a transesterification reaction or the like usually occurs as another reaction, and the obtained reaction product is generally a composition containing unreacted raw materials. In such a case, the content of the modified polyester elastomer in the obtained reaction product is about 10% by mass or more, more preferably about 30% by mass or more, and the content of the modified polyester elastomer is about 100% by mass. Further preferred.

Examples of the α, β-ethylenically unsaturated carboxylic acid used as the modifier include unsaturated carboxylic acids such as acrylic acid, maleic acid, fumaric acid, tetrahydrofumaric acid, itaconic acid, citraconic acid, crotonic acid, and isocrotonic acid. Acid; 2-octen-1-yl succinic anhydride, 2-dodecen-1-yl succinic anhydride, 2-octadecen-1-yl succinic anhydride, maleic anhydride, 2,3-dimethylmaleic acid Anhydride, bromomaleic anhydride, dichloromaleic anhydride, citraconic anhydride, itaconic anhydride, 1-butene-3,4-dicarboxylic anhydride, 1-cyclopentene-1,2-

dicarboxylic anhydride

1,2,3,6-tetrahydrophthalic anhydride, 3,4,5,6-tetrahydrophthalic anhydride, exo-3,6-

epoxy

1,2,3,6-tetrahydrophthalic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, methyl-5-norbornene-2,3-dicarboxylic anhydride, endo-bicyclo [2.2. 2] Unsaturated carboxylic acids such as oct-5-ene-2,3-dicarboxylic acid anhydride and bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic acid anhydride Anhydrides are mentioned. Of these, acid anhydrides are preferred because of their high reactivity. The α, β-ethylenically unsaturated carboxylic acid can be appropriately selected according to the copolymer containing the polyalkylene ether glycol segment to be modified and the modification conditions, and two or more types may be used in combination. . The α, β-ethylenically unsaturated carboxylic acid can also be used after being dissolved in an organic solvent.

Examples of the radical generator include t-butyl hydroperoxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-bis (t -Butylperoxy) hexane, 3,5,5-trimethylhexanoyl peroxide, t-butylperoxybenzoate, benzoyl peroxide, dicumyl peroxide, 1,3-bis (t-butylperoxyisopropyl) benzene Organic and inorganic peroxides such as dibutyl peroxide, methyl ethyl ketone peroxide, potassium peroxide, hydrogen peroxide, 2,2′-azobisisobutyronitrile, 2,2′-azobis (isobutylamide) dihalide, 2,2'-azobis [2-methyl-N- (2-hydroxy Ethyl) propionamide], azo compounds such as azodi -t- butane, and carbon radical generators such as dicumyl.

The radical generator can be appropriately selected according to the type of polyester elastomer used in the modification reaction, the type of α, β-ethylenically unsaturated carboxylic acid and the modification conditions, and two or more types can be used in combination. Also good. Furthermore, the radical generator can be used by dissolving in an organic solvent.

The preferable lower limit of the blending amount of the α, β-ethylenically unsaturated carboxylic acid is about 0.01 parts by mass or more and the preferable upper limit is about 30.0 parts by mass or less with respect to 100 parts by mass of the polyester elastomer. When the amount is about 0.01 parts by mass or more, the modification reaction can be sufficiently performed, and when the amount is about 30.0 parts by mass or less, it is economically advantageous. A more preferred lower limit is about 0.05 parts by mass or more, a more preferred upper limit is about 5.0 parts by mass or less, a further preferred lower limit is about 0.10 parts by mass or more, and a more preferred upper limit is about 1.0 part by mass or less.

The preferable lower limit of the blending amount of the radical generator is about 0.001 part by mass or more with respect to 100 parts by mass of the polyester elastomer, and the preferable upper limit is about 3.00 part by mass or less. When it is about 0.001 part by mass or more, a modification reaction is likely to occur, and when it is about 3.00 part by mass or less, a decrease in material strength due to low molecular weight (decrease in viscosity) at the time of modification hardly occurs. . A more preferred lower limit is about 0.005 parts by mass or more, a more preferred upper limit is about 0.50 parts by mass or less, a still more preferred lower limit is about 0.010 parts by mass or more, and a more preferred upper limit is about 0.20 parts by mass or less. A particularly preferred upper limit is about 0.10 parts by mass or less.

As the modification reaction for obtaining the modified polyester-based elastomer, known reaction methods such as a melt-kneading reaction method, a solution reaction method, and a suspension-dispersion reaction can be used. Reaction methods are preferred.

In the method based on the melt kneading reaction method, the above-described components are uniformly mixed at a predetermined blending ratio and then melt kneaded. Henschel mixer, ribbon blender, V-type blender, etc. can be used for mixing each component, and Banbury mixer, kneader, roll, uniaxial or biaxial multi-screw kneading extruder etc. are used for melt-kneading. can do.

The preferred lower limit of the kneading temperature when melt kneading is about 100 ° C. or more, and the preferred upper limit is about 300 ° C. or less. By setting it within the above range, thermal deterioration of the resin can be prevented. A more preferred lower limit is about 120 ° C. or more, a more preferred upper limit is about 280 ° C. or less, a still more preferred lower limit is about 150 ° C. or more, and a still more preferred upper limit is about 250 ° C. or less.

The preferable lower limit of the modification rate (graft amount) of the modified polyester elastomer is about 0.01% by mass or more, and the preferable upper limit is about 10.0% by mass or less. When the content is about 0.01% by mass or more, the affinity with the polyester is increased, and when the content is about 10.0% by mass or less, a decrease in strength due to molecular degradation during modification can be reduced. A more preferred lower limit is about 0.03% by mass or more, a more preferred upper limit is about 7.0% by mass or less, a still more preferred lower limit is about 0.05% by mass or more, and a further more preferred upper limit is about 5.0% by mass or less. is there.

The modification rate (graft amount) of the modified polyester elastomer can be determined from the spectrum obtained by H ¹ -NMR measurement.

The material constituting the resin layer 1a is not particularly limited, and examples thereof include a thermoplastic resin and a thermosetting resin, and preferably a thermoplastic resin. Although it does not restrict | limit especially as a thermoplastic resin, From a viewpoint of suppressing deterioration of the surface characteristic by the side of the base material layer 2 of a battery packaging material, Preferably, a polyester resin, a polyamide resin, an acrylic resin, a polyolefin resin, a polycarbonate resin Among these, among these, a polyester resin is more preferable. In particular, from the viewpoint of increasing the mechanical strength of the resin layer 1a and suitably separating the resin layer 1a, the resin layer 1a is preferably made of a biaxially stretched polyester film. The biaxially stretched polyester film has enhanced orientation and is excellent in moldability, tensile strength, and puncture strength. The resin constituting the resin layer 1a may be only one type or two or more types.

Preferred examples of the polyester resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, and copolyester. The polyester resin may be composed of only one type or may be composed of two or more types. The polyester resin may contain, for example, polyethylene terephthalate as a main component (the content is, for example, 90% by mass or more, 95% by mass or more, 99% by mass or more), and polybutylene terephthalate may be included as a subcomponent.

The resin constituting the resin layer 1a preferably has a higher melting point than the resin constituting the base material layer 2. Due to the high melting point of the resin constituting the resin layer 1a, the deterioration of the base material layer 2 due to high temperature and high pressure when the heat-fusible resin layer 4 of the battery packaging material is heat-sealed is caused by the resin layer 1a. It can suppress effectively by protection by. As an aspect in which the deterioration suppressing effect of the base material layer 2 by the resin layer 1a is particularly effectively exhibited, there is an aspect in which the resin layer 1a is made of a polyester resin and the base material layer 2 is made of polyamide.

In the present invention, in the resin layer 1a, in the probe displacement measurement using thermomechanical analysis, the probe is placed on the surface of the resin layer 1a at the end of the battery packaging material (laminate), and the probe at the start of measurement When the probe is heated from 40 ° C. to 220 ° C. under the condition that the deflection is set to -4V and the temperature raising rate is 5 ° C./min, the position of the probe is preferably not lower than the initial value. . Thereby, degradation of the base material layer 2 due to high temperature and high pressure when the heat-fusible resin layer 4 of the battery packaging material is heat-sealed can be effectively suppressed by the protection by the resin layer 1a.

In measuring the displacement of the probe, first, the probe is placed on the surface of the resin layer 1a at the end of the battery packaging material (laminated body). The edge part at this time is a part where the cross section of the resin layer 1a obtained by cutting in the thickness direction so as to pass through the central part of the battery packaging material is exposed. Cutting can be performed using a commercially available rotary microtome or the like. When the amount of displacement is measured for battery packaging materials used in batteries encapsulating electrolytes, etc., the portions where the heat-fusible resin layers of the battery packaging materials are heat-sealed together. , Measure. As an atomic force microscope to which a cantilever with a heating mechanism can be attached, for example, an afm plus system manufactured by ANASIS INSTRUMENTS is used, and a cantilever ThermoLever AN2-200 manufactured by ANASYS INSTRUMENTS is used as a probe (spring constant 0.5 to 3 N / m). ) Can be used. The probe tip radius is 30 nm or less, the probe deflection setting is −4 V, and the temperature rise rate is 5 ° C./min. Next, when the probe is heated in this state, the surface of the resin layer 1a is expanded by the heat from the probe, the probe is pushed up, and the probe position is the initial value (position when the probe temperature is 40 ° C.). Than to rise. When the heating temperature is further increased, the resin layer 1a is softened, the probe is pierced into the resin layer 1a, and the position of the probe is lowered. In the probe displacement measurement using an atomic force microscope including a nanothermal microscope composed of a cantilever with a heating mechanism, the battery packaging material to be measured is in a room temperature (25 ° C.) environment. A probe heated to ° C is placed on the surface of the resin layer 1a, and measurement is started.

In the battery packaging material of the present invention, from the viewpoint of further improving the insulation and durability, the set value of the deflection of the probe at the start of measurement is −4 V, and the temperature rising rate is 5 ° C./min. Thus, when the probe is heated from 40 ° C. to 220 ° C., the position of the probe installed on the surface of the resin layer 1a is not lowered below the initial value (position when the probe temperature is 40 ° C.). It is more preferable that the position of the probe placed on the surface of the resin layer 1a does not decrease when heated from 200C to 200C. The step of heat-sealing the heat-fusible resin layers of the battery packaging material to seal the battery element is usually performed by heating at about 160 ° C. to 200 ° C. For this reason, when the probe is heated from 160 ° C. to 200 ° C., the battery packaging material in which the position of the probe installed on the surface of the resin layer 1a does not decrease can exhibit particularly high heat resistance. From the viewpoint of further increasing the heat resistance, when the probe is heated from 40 ° C. to 250 ° C., the position of the probe placed on the surface of the resin layer 1a is not lowered below the initial value, and further, heated from 160 ° C. to 200 ° C. More preferably, the position of the probe placed on the surface of the resin layer 1a does not decrease.

The thickness of the resin layer 1a is not particularly limited, but is preferably about 2 to 50 μm, more preferably about 2 to 20 μm, from the viewpoint of suppressing deterioration of surface characteristics on the base material layer 2 side of the battery packaging material. More preferably, it is about 2 to 10 μm.

From the same viewpoint, the thickness of the bonding layer 1b is preferably about 0.2 to 10 μm, more preferably about 0.2 to 5 μm, and still more preferably about 0.2 to 3 μm. From the same viewpoint, the total thickness of the resin layer 1a and the bonding layer 1b is preferably about 2 to 50 μm, more preferably about 2 to 20 μm, and further preferably about 2 to 10 μm.

A lubricant may be present on the surface of the resin layer 1a. Since the lubricant is present on the surface of the resin layer 1a, the moldability of the battery packaging material can be improved. The type of the lubricant is not particularly limited, and examples thereof include the same lubricants exemplified in the heat-fusible resin layer described later. Preferable lubricants are erucic acid amide, palmitic acid amide, stearic acid amide, and oleic acid amide, and more preferable lubricant is erucic acid amide. The amount of lubricant present on the surface of the resin layer 1a is preferably about 2 to 20 g / m ² , more preferably about 3 to 17 g / m ² , and further preferably about 3 to 8 g / m ² . The lubricant present on the surface of the resin layer 1a may be exuded from the inside of the resin layer 1a, or may be applied on the surface of the resin layer 1a. The amount of lubricant present on the surface of the resin layer 1a can be confirmed by the following measuring method.

(Measurement of lubricant amount)
A battery packaging material is cut into A4 size (ISO 216) to prepare a sample. Next, the resin layer surface of each sample is washed with acetone, and the collected acetone is volatilized and dried by nitrogen blowing to obtain a solid. Next, 10 ml of chloroform was added to the solid substance to redissolve the solid substance, and a gas chromatograph (GC, for example, GC-2010 manufactured by Shimadzu Corporation, column: UltraALLOY-1 (MS / HT), detector: FID, Quantitative method: Absolute calibration curve method) is used to measure the amount of lubricant on the resin layer surface.

[Base material layer 2]
In the battery packaging material of the present invention, after the resin layer 1a is peeled off, the base material layer 2 becomes a layer located on the outermost layer side. When no other layer (for example, a surface coating layer described later) is provided between the resin layer 1a and the base material layer 2, the base material layer 2 is a layer adjacent to the bonding layer 1b.

The material for forming the base material layer 2 is not particularly limited as long as it has insulating properties. Examples of the material for forming the base material layer 2 include resin films such as polyester resin, polyamide resin, epoxy resin, acrylic resin, fluorine resin, polyurethane resin, silicon resin, phenol resin, and mixtures and copolymers thereof. Can be mentioned. Among these, Preferably a polyester resin and a polyamide resin are mentioned, More preferably, a biaxially stretched polyester resin and a biaxially stretched polyamide resin are mentioned. Specific examples of the polyester resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, copolymerized polyester, and polycarbonate. Specific examples of the polyamide resin include nylon 6, nylon 66, a copolymer of nylon 6 and nylon 66,

nylon

6,10, polymetaxylylene adipamide (MXD6), and the like. The polyamide resin may be composed of only one type or may be composed of two or more types. The polyamide resin may contain, for example, nylon 6 and polymetaxylylene adipamide (MXD6).

The base material layer 2 may be formed from a single resin film, but may be formed from two or more resin films in order to improve pinhole resistance and insulation. Specific examples include a multilayer structure in which a polyester film and a nylon film are laminated, a multilayer structure in which a plurality of nylon films are laminated, a multilayer structure in which a plurality of polyester films are laminated, and the like. When the base material layer 2 has a multilayer structure, a laminate of a biaxially stretched nylon film and a biaxially stretched polyester film, a laminate of a plurality of biaxially stretched nylon films, and a laminate of a plurality of biaxially stretched polyester films The body is preferred. For example, when the base material layer 2 is formed from two resin films, a configuration in which a polyester resin and a polyester resin are stacked, a configuration in which a polyamide resin and a polyamide resin are stacked, or a configuration in which a polyester resin and a polyamide resin are stacked are used. It is more preferable to use a structure in which polyethylene terephthalate and polyethylene terephthalate are laminated, a structure in which nylon and nylon are laminated, or a structure in which polyethylene terephthalate and nylon are laminated. When the base material layer 2 has a multilayer structure, the thickness of each layer is preferably about 2 to 25 μm.

When the base material layer 2 is formed of a multilayer resin film, the two or more resin films may be laminated via an adhesive component such as an adhesive or an adhesive resin, and the type and amount of the adhesive component used. This is the same as in the case of the adhesive layer 5 described later. In addition, it does not restrict | limit especially as a method of laminating | stacking two or more resin films, A well-known method can be employ | adopted, for example, a dry lamination method, a sandwich lamination method, etc. are mentioned, Preferably the dry lamination method is mentioned. When laminating by the dry laminating method, it is preferable to use a urethane-based adhesive as the adhesive layer. At this time, the thickness of the adhesive layer is, for example, about 2 to 5 μm.

The thickness of the base material layer 2 is not particularly limited as long as it exhibits a function as a base material layer, and is, for example, about 3 to 50 μm, preferably about 10 to 35 μm.

[Adhesive layer 5]
In the battery packaging material 10 of the present invention, the adhesive layer 5 is a layer provided between the base material layer 2 and the barrier layer 3 as necessary in order to firmly bond the base material layer 2 and the barrier layer 3.

The adhesive layer 5 is formed of an adhesive capable of bonding the base material layer 2 and the barrier layer 3 together. The adhesive used for forming the adhesive layer 5 may be a two-component curable adhesive or a one-component curable adhesive. Further, the adhesive mechanism of the adhesive used for forming the adhesive layer 5 is not particularly limited, and may be any of a chemical reaction type, a solvent volatilization type, a heat melting type, and a hot pressure type.

Specific examples of adhesive components that can be used to form the adhesive layer 5 include polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, polycarbonate, and copolyester; Polyether adhesives; Polyurethane adhesives; Epoxy resins; Phenol resin resins; Polyamide resins such as nylon 6, nylon 66, nylon 12 and copolymerized polyamides; polyolefins, carboxylic acid modified polyolefins, metal modified polyolefins, etc. Polyolefin resins, polyvinyl acetate resins; Cellulosic adhesives; (Meth) acrylic resins; Polyimide resins; Urea resins, melamine resins and other amino resins; Chloroprene rubber, Nitriles - arm, styrene rubbers such as butadiene rubber; and silicone resins. These adhesive components may be used individually by 1 type, and may be used in combination of 2 or more type. Among these adhesive components, a polyurethane adhesive is preferable.

The thickness of the adhesive layer 5 is not particularly limited as long as it exhibits a function as an adhesive layer, and for example, it is about 1 to 10 μm, preferably about 2 to 5 μm.

An ultraviolet absorber for a layer outside the barrier layer 3 of the battery packaging material of the present invention (preferably at least one of the resin layer 1a, the bonding layer 1b, the base material layer 2 and the adhesive layer 5), It is preferable to contain at least one component among the light stabilizer and the antioxidant. By including one of these components, delamination between layers is effectively suppressed outside the barrier layer 3.

In the present invention, delamination of the layer outside the barrier layer 3 of the battery packaging material mainly means delamination between these layers.

The presence of these components in the outer layer of the barrier layer 3 of the battery packaging material of the present invention can be analyzed using, for example, a gas chromatograph mass spectrometer (GC / MS). When it is trace amount and cannot be detected by GC / MS, it can be analyzed by, for example, liquid chromatography (HPLC). Pre-processing is performed as follows.

∙ Physically peel the substrate layer (the resin layer and the bonding layer are laminated) and the barrier layer without using a solvent. Next, in order to increase the extraction efficiency of the additive component in each layer, the laminate of the resin layer, the bonding layer, and the base material layer is wound and extracted with a stainless steel mesh so that the adhesion between the layers is reduced. . Next, using chloroform as the extraction solvent, Soxhlet extraction is performed for 10 hours to extract the additive components. After distilling off the solvent, it is dissolved in the measurement solvent and used for analysis.

The ultraviolet absorber contained in the outer layer (preferably at least one of the resin layer 1a, the bonding layer 1b, the base material layer 2, and the adhesive layer 5) of the battery packaging material of the present invention. The total content of is preferably 10 to 500 ppm, more preferably about 30 to 100 ppm, and particularly preferably about 40 to 80 ppm from the viewpoint of interlayer adhesion stability. Further, the total content of the light stabilizer is preferably 10 to 500 ppm, more preferably about 100 to 200 ppm, and particularly preferably 120 to 180 ppm from the viewpoint of interlayer adhesion stability. The total content of the antioxidant is preferably 10 to 1000 ppm, more preferably about 200 to 800 ppm, and particularly preferably about 420 to 600 ppm from the viewpoint of interlayer adhesion stability.

The type of the ultraviolet absorber is not particularly limited, but a benzotriazole-based ultraviolet absorber is preferable. Specific examples of the ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, and 5,5′-methylenebis (2-hydroxy-4-methoxybenzophenone). 2-hydroxybenzophenones such as 2-; 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy-3, 5-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3,5 -Dicumylphenyl) benzotriazole, 2,2'-methylenebis (4-tertiary o Polyethylene glycol ester of 2- (2-hydroxy-3-tert-butyl-5-carboxyphenyl) benzotriazole, 2- [2-hydroxy-3- (2-acryloyloxy) Ethyl) -5-methylphenyl] benzotriazole, 2- [2-hydroxy-3- (2-methacryloyloxyethyl) -5-tert-butylphenyl] benzotriazole, 2- [2-hydroxy-3- (2- Methacryloyloxyethyl) -5-tert-octylphenyl] benzotriazole, 2- [2-hydroxy-3- (2-methacryloyloxyethyl) -5-tert-butylphenyl] -5-chlorobenzotriazole, 2- [2 -Hydroxy-5- (2-methacryloyloxyethyl) phenyl] benzo Riazole, 2- [2-hydroxy-3-tert-butyl-5- (2-methacryloyloxyethyl) phenyl] benzotriazole, 2- [2-hydroxy-3-tert-amyl-5- (2-methacryloyloxyethyl) ) Phenyl] benzotriazole, 2- [2-hydroxy-3-tert-butyl-5- (3-methacryloyloxypropyl) phenyl] -5-chlorobenzotriazole, 2- [2-hydroxy-4- (2-methacryloyl) Oxymethyl) phenyl] benzotriazole, 2- [2-hydroxy-4- (3-methacryloyloxy-2-hydroxypropyl) phenyl] benzotriazole, 2- [2-hydroxy-4- (3-methacryloyloxypropyl) phenyl ] 2- (2-hydroxyphenyl) such as benzotriazole Benzotriazoles; 2- (2-hydroxy-4-methoxyphenyl) -4,6-diphenyl-1,3,5-triazine, 2- (2-hydroxy-4-hexyloxyphenyl) -4,6-diphenyl -1,3,5-triazine, 2- (2-hydroxy-4-octoxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- [2- Hydroxy-4- (3-C12-13 mixed alkoxy-2-hydroxypropoxy) phenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- [2-hydroxy- 4- (2-acryloyloxyethoxy) phenyl] -4,6-bis (4-methylphenyl) -1,3,5-triazine, 2- (2,4-dihydroxy-3-allylphenyl)- , 6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-hexyloxyphenyl) -1,3,5- 2- (2-hydroxyphenyl) -4,6-diaryl-1,3,5-triazines such as triazine; phenyl salicylate, resorcinol monobenzoate, 2,4-ditertiarybutylphenyl-3,5-diter Tributyl-4-hydroxybenzoate, octyl (3,5-ditert-butyl-4-hydroxy) benzoate, dodecyl (3,5-ditert-butyl-4-hydroxy) benzoate, tetradecyl (3,5-ditert Tributyl-4-hydroxy) benzoate, hexadecyl (3,5-ditert-butyl-4-hydroxy) benzoate, octadecyl (3,5-ditert-butyl) Benzoates such as ru-4-hydroxy) benzoate and behenyl (3,5-ditert-butyl-4-hydroxy) benzoate; 2-ethyl-2′-ethoxyoxanilide, 2-ethoxy-4′-dodecyloxy Substituted oxanilides such as zanilides; cyanoacrylates such as ethyl-α-cyano-β, β-diphenyl acrylate, methyl-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate; various metal salts Or metal chelates, especially nickel, chromium salts, or chelates. Examples of commercially available ultraviolet absorbers include TINUVIN571, TINUVIN460, TINUVIN213, TINUVIN234, TINUVIN329, and TINUVIN326 manufactured by BASF, and among these, TINUVIN326 (2- [5-chloro (2H) -benzotriazole- 2-yl] -4-methyl-6- (tert-butyl) phenol) is effective.

UV absorbers may be used alone or in combination of two or more.

The type of light stabilizer is not particularly limited, but a hindered amine light stabilizer is preferable. Specific examples of the light stabilizer include, for example, 2,2,6,6-tetramethyl-4-piperidyl stearate, 1,2,2,6,6-pentamethyl-4-piperidyl stearate, 2,2, 6,6-tetramethyl-4-piperidylbenzoate, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1 , 2,3,4-butanetetracarboxylate, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, bis (2,2, 6,6-tetramethyl-4-piperidyl) -di (tridecyl) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) Di (tridecyl) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,4,4-pentamethyl-4-piperidyl) -2-butyl-2- (3,5-di Tributyl-4-hydroxybenzyl) malonate, 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol / diethyl succinate polycondensate, 1,6-bis (2 , 2,6,6-Tetramethyl-4-piperidylamino) hexane / 2,4-dichloro-6-morpholino-s-triazine polycondensate, 1,6-bis (2,2,6,6-tetramethyl -4-piperidylamino) hexane / 2,4-dichloro-6-tert-octylamino-s-triazine polycondensate, 1,5,8,12-tetrakis [2,4-bis (N-butyl-N- (2,2,6,6-tetra Til-4-piperidyl) amino) -s-triazin-6-yl] -1,5,8,12-tetraazadodecane, 1,5,8,12-tetrakis [2,4-bis (N-butyl-) N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino) -s-triazin-6-yl] -1,5,8-12-tetraazadodecane, 1,6,11-tris [2,4-bis (N-butyl-N- (2,2,6,6-tetramethyl-4-piperidyl) amino) -s-triazin-6-yl] aminoundecane, 1,6,11-tris [2,4-bis (N-butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino) -s-triazin-6-yl] aminoundecane, bis {4- (1 -Octyloxy-2,2,6,6-tetramethyl) piperi Zil} decanedionate, bis {4- (2,2,6,6-tetramethyl-1-undecyloxy) piperidyl) carbonate and the like. Among these, compounds in which the one linked to the position 1 of piperidine is N-oxyalkyl or N-methyl are preferable. Commercially available light stabilizers include TINUVIN 765, TINUVIN 770, TINUVIN 780, TINUVIN 144, and TINUVIN 622LD manufactured by BASF, and particularly TINUVIN 770 (bis (2,2,6,6-tetramethyl-4-piperidyl sebacate)). ) Is effective.

光 One kind of light stabilizer may be used alone, or two or more kinds may be used in combination.

Further, the type of the antioxidant is not particularly limited, but preferably a hindered phenol antioxidant is used. Specific examples of the antioxidant include Irganox 1330 (2,4,6-tris (3 ′, 5′-di-tert-butyl-4′-hydroxybenzyl) mesitylene), Irganox 1098 (N, N′-hexamethylenebis) [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propanamide]), Irganox 1010 (tetrakis [3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propion Acid] pentaerythritol). When Irganox 1330 is included as an antioxidant, from the viewpoint of adhesion stability between layers, a layer outside the barrier layer 3 of the battery packaging material of the present invention (preferably, a resin layer 1a, a bonding layer 1b, a base material) The total content of Irganox 1330 contained in at least one of the layer 2 and the adhesive layer 5) is preferably about 10 to 500 ppm, more preferably about 90 to 200 ppm, and particularly preferably about 110 to 170 ppm. .

One type of antioxidant may be used alone, or two or more types may be used in combination.

[Barrier layer 3]
In the battery packaging material, the barrier layer 3 is a layer having a function of preventing water vapor, oxygen, light and the like from entering the battery, in addition to improving the strength of the battery packaging material. The barrier layer 3 is preferably a metal layer, that is, a layer formed of metal. Specific examples of the metal constituting the barrier layer 3 include aluminum, stainless steel, and titanium, and preferably aluminum. The barrier layer 3 can be formed by, for example, a metal foil, a metal vapor-deposited film, an inorganic oxide vapor-deposited film, a carbon-containing inorganic oxide vapor-deposited film, a film provided with these vapor-deposited films, etc. Is preferable, and it is more preferable to form with an aluminum alloy foil. From the viewpoint of preventing the generation of wrinkles and pinholes in the barrier layer 3 during the production of the battery packaging material, the barrier layer is made of, for example, annealed aluminum (JIS H4160: 1994 A8021H-O, JIS H4160: 1994 A8079H-O, JIS H4000: 2014 A8021P-O, JIS H4000: 2014 A8079P-O) and the like are more preferable.

The thickness of the barrier layer 3 is not particularly limited as long as it functions as a barrier layer such as water vapor, but is preferably about 100 μm or less, more preferably about 10 to 100 μm from the viewpoint of reducing the thickness of the battery packaging material. More preferably, about 10 to 80 μm is mentioned.

The barrier layer 3 is preferably subjected to chemical conversion treatment on at least one side, preferably both sides, in order to stabilize adhesion, prevent dissolution and corrosion, and the like. Here, the chemical conversion treatment refers to a treatment for forming an acid-resistant film on the surface of the barrier layer. As the chemical conversion treatment, for example, chromate treatment using a chromium compound such as chromium nitrate, chromium fluoride, chromium sulfate, chromium acetate, chromium oxalate, chromium biphosphate, chromic acid acetyl acetate, chromium chloride, potassium sulfate chromium; Phosphoric acid treatment using a phosphoric acid compound such as sodium phosphate, potassium phosphate, ammonium phosphate, polyphosphoric acid; an aminated phenol polymer having a repeating unit represented by the following general formulas (1) to (4) is used And chromate treatment. In the aminated phenol polymer, the repeating units represented by the following general formulas (1) to (4) may be contained singly or in any combination of two or more. Also good.

In the general formulas (1) to (4), X represents a hydrogen atom, a hydroxy group, an alkyl group, a hydroxyalkyl group, an allyl group or a benzyl group. R ¹ and R ² are the same or different and each represents a hydroxy group, an alkyl group, or a hydroxyalkyl group. In the general formulas (1) to (4), examples of the alkyl group represented by X, R ¹ and R ² include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, Examples thereof include straight-chain or branched alkyl groups having 1 to 4 carbon atoms such as a tert-butyl group. Examples of the hydroxyalkyl group represented by X, R ¹ and R ² include a hydroxymethyl group, a 1-hydroxyethyl group, a 2-hydroxyethyl group, a 1-hydroxypropyl group, a 2-hydroxypropyl group, 3- Linear or branched chain having 1 to 4 carbon atoms substituted with one hydroxy group such as hydroxypropyl group, 1-hydroxybutyl group, 2-hydroxybutyl group, 3-hydroxybutyl group, 4-hydroxybutyl group An alkyl group is mentioned. In the general formulas (1) to (4), the alkyl group and hydroxyalkyl group represented by X, R ¹ and R ² may be the same or different. In the general formulas (1) to (4), X is preferably a hydrogen atom, a hydroxy group or a hydroxyalkyl group. The number average molecular weight of the aminated phenol polymer having a repeating unit represented by the general formulas (1) to (4) is preferably about 500 to 1,000,000, for example, about 1,000 to 20,000. More preferred.

Further, as a chemical conversion treatment method for imparting corrosion resistance to the barrier layer 3, a phosphoric acid is coated with a metal oxide such as aluminum oxide, titanium oxide, cerium oxide, tin oxide, or barium sulfate fine particles dispersed therein. A method of forming an acid-resistant film on the surface of the barrier layer 3 by performing a baking treatment at 150 ° C. or higher can be mentioned. Further, a resin layer obtained by crosslinking a cationic polymer with a crosslinking agent may be further formed on the acid resistant film. Here, examples of the cationic polymer include polyethyleneimine, an ionic polymer complex composed of a polymer having polyethyleneimine and a carboxylic acid, a primary amine graft acrylic resin obtained by graft polymerization of a primary amine on an acrylic main skeleton, and polyallylamine. Or the derivative, aminophenol, etc. are mentioned. As these cationic polymers, only one type may be used, or two or more types may be used in combination. Examples of the crosslinking agent include a compound having at least one functional group selected from the group consisting of an isocyanate group, a glycidyl group, a carboxyl group, and an oxazoline group, and a silane coupling agent. As these crosslinking agents, only one type may be used, or two or more types may be used in combination.

In addition, as a method for specifically providing an acid-resistant film, for example, as an example, at least the surface on the inner layer side of the aluminum alloy foil is firstly immersed in an alkali soaking method, electrolytic cleaning method, acid cleaning method, electrolytic acid cleaning method. , Degreased by a known treatment method such as an acid activation method, and then a phosphoric acid metal salt such as chromium phosphate salt, titanium phosphate salt, zirconium phosphate salt, zinc phosphate salt and the like Treatment liquid (aqueous solution) mainly composed of a mixture of metal salts, or treatment liquid (aqueous solution) principally composed of a non-metallic phosphate and a mixture of these non-metallic salts, or acrylic resin Coating a treatment liquid (aqueous solution) consisting of a mixture with a water-based synthetic resin such as phenolic resin or urethane resin by a well-known coating method such as roll coating, gravure printing, or dipping. More, it is possible to form the acid-resistant coating. For example, when treated with a chromium phosphate salt treatment solution, it becomes an acid-resistant film made of chromium phosphate, aluminum phosphate, aluminum oxide, aluminum hydroxide, aluminum fluoride, etc., and treated with a zinc phosphate salt treatment solution. In this case, an acid-resistant film made of zinc phosphate hydrate, aluminum phosphate, aluminum oxide, aluminum hydroxide, aluminum fluoride or the like is obtained.

In addition, as another example of a specific method for providing an acid-resistant film, for example, at least the surface on the inner layer side of the aluminum alloy foil is first subjected to an alkali dipping method, an electrolytic cleaning method, an acid cleaning method, an electrolytic acid cleaning method, an acid An acid-resistant film can be formed by performing a degreasing process by a known processing method such as an activation method and then performing a known anodizing process on the degreasing surface.

Also, other examples of acid-resistant films include phosphate-based and chromic acid-based films. Examples of the phosphate system include zinc phosphate, iron phosphate, manganese phosphate, calcium phosphate, and chromium phosphate. Examples of the chromic acid system include chromium chromate.

In addition, as another example of the acid-resistant film, by forming an acid-resistant film such as phosphate, chromate, fluoride, triazine thiol compound, between the aluminum and the base material layer at the time of embossing molding Prevention of delamination, hydrogen fluoride generated by the reaction between electrolyte and moisture prevents dissolution and corrosion of the aluminum surface, especially the dissolution and corrosion of aluminum oxide present on the aluminum surface, and adhesion of the aluminum surface This improves the wettability and prevents delamination between the base material layer and aluminum at the time of heat sealing. In the embossed type, it shows the effect of preventing delamination between the base material layer and aluminum at the time of press molding. Among substances that form an acid-resistant film, an aqueous solution composed of three components of a phenol resin, a chromium (III) fluoride compound, and phosphoric acid is applied to the aluminum surface, and the dry baking treatment is good.

The acid-resistant film includes a layer having cerium oxide, phosphoric acid or phosphate, an anionic polymer, and a crosslinking agent that crosslinks the anionic polymer, and the phosphoric acid or phosphate is About 1 to 100 parts by mass may be blended with 100 parts by mass of cerium oxide. It is preferable that the acid-resistant film has a multilayer structure further including a layer having a cationic polymer and a crosslinking agent for crosslinking the cationic polymer.

Furthermore, it is preferable that the anionic polymer is poly (meth) acrylic acid or a salt thereof, or a copolymer containing (meth) acrylic acid or a salt thereof as a main component. Moreover, it is preferable that the said crosslinking agent is at least 1 sort (s) chosen from the group which has a functional group in any one of an isocyanate group, a glycidyl group, a carboxyl group, and an oxazoline group, and a silane coupling agent.

Moreover, it is preferable that the phosphoric acid or the phosphate is a condensed phosphoric acid or a condensed phosphate.

As the chemical conversion treatment, only one type of chemical conversion treatment may be performed, or two or more types of chemical conversion processing may be performed in combination. Furthermore, these chemical conversion treatments may be carried out using one kind of compound alone, or may be carried out using a combination of two or more kinds of compounds. Among the chemical conversion treatments, a chromate chromate treatment, a chemical conversion treatment combining a chromium compound, a phosphoric acid compound, and an aminated phenol polymer are preferable. Of the chromium compounds, chromic acid compounds are preferred.

Specific examples of the acid resistant film include those containing at least one of phosphate, chromate, fluoride, and triazine thiol. An acid resistant film containing a cerium compound is also preferable. As the cerium compound, cerium oxide is preferable.

Specific examples of the acid resistant film include a phosphate film, a chromate film, a fluoride film, and a triazine thiol compound film. As an acid-resistant film, one of these may be used, or a plurality of combinations may be used. Furthermore, as an acid-resistant film, after degreasing the chemical conversion treatment surface of the aluminum alloy foil, a treatment solution comprising a mixture of a metal phosphate and an aqueous synthetic resin, or a mixture of a non-metal phosphate and an aqueous synthetic resin It may be formed of a treatment liquid consisting of

The composition of the acid resistant film can be analyzed using, for example, time-of-flight secondary ion mass spectrometry. By analyzing the composition of the acid-resistant film using time-of-flight secondary ion mass spectrometry, for example, a peak derived from at least one of Ce ⁺ and Cr ⁺ is detected.

It is preferable that the surface of the aluminum alloy foil is provided with an acid resistant film containing at least one element selected from the group consisting of phosphorus, chromium and cerium. Note that the acid-resistant film on the surface of the aluminum alloy foil of the battery packaging material contains at least one element selected from the group consisting of phosphorus, chromium and cerium using X-ray photoelectron spectroscopy. can do. Specifically, first, in the battery packaging material, the heat-fusible resin layer, the adhesive layer, and the like laminated on the aluminum alloy foil are physically peeled off. Next, the aluminum alloy foil is put in an electric furnace, and organic components present on the surface of the aluminum alloy foil are removed at about 300 ° C. for about 30 minutes. Then, it confirms that these elements are contained using the X-ray photoelectron spectroscopy of the surface of aluminum alloy foil.

The amount of the acid-resistant film to be formed on the surface of the barrier layer 3 in the chemical conversion treatment is not particularly limited. For example, if the above chromate treatment is performed, the chromium compound is chromium per 1 m ² of the surface of the barrier layer 3. About 0.5 to 50 mg in terms of conversion, preferably about 1.0 to 40 mg, about 0.5 to 50 mg, preferably about 1.0 to 40 mg in terms of phosphorus, and about 1.0 to 40 mg of aminated phenol polymer. It is desirable that it is contained in a proportion of about 200 mg, preferably about 5.0 to 150 mg.

The thickness of the acid-resistant film is not particularly limited, but is preferably about 1 nm to 10 μm, more preferably 1 to 100 nm, from the viewpoint of the cohesive strength of the film and the adhesive strength with the aluminum alloy foil or the heat-fusible resin layer. About 1 to 50 nm is preferable. The thickness of the acid-resistant film can be measured by observation with a transmission electron microscope or a combination of observation with a transmission electron microscope and energy dispersive X-ray spectroscopy or electron energy loss spectroscopy.

In the chemical conversion treatment, a solution containing a compound used for forming an acid-resistant film is applied to the surface of the barrier layer by a bar coating method, a roll coating method, a gravure coating method, a dipping method, etc., and then the temperature of the barrier layer is 70. It is performed by heating to about 200 ° C. In addition, before the chemical conversion treatment is performed on the barrier layer, the barrier layer may be previously subjected to a degreasing treatment by an alkali dipping method, an electrolytic cleaning method, an acid cleaning method, an electrolytic acid cleaning method, or the like. By performing the degreasing process in this manner, it is possible to more efficiently perform the chemical conversion process on the surface of the barrier layer.

[Heat-fusion resin layer 4]
In the battery packaging material of the present invention, the heat-fusible resin layer 4 corresponds to the innermost layer, and is a layer that heat-fuses the heat-fusible resin layers and seals the battery element when the battery is assembled.

The resin component used for the heat-fusible resin layer 4 is not particularly limited as long as it can be heat-sealed, and examples thereof include polyolefin, cyclic polyolefin, acid-modified polyolefin, and acid-modified cyclic polyolefin. That is, the heat-fusible resin layer 4 may include a polyolefin skeleton, and preferably includes a polyolefin skeleton. The fact that the heat-fusible resin layer 4 contains a polyolefin skeleton can be analyzed by, for example, infrared spectroscopy, gas chromatography mass spectrometry, etc., and the analysis method is not particularly limited. For example, when measuring the infrared spectroscopy at a maleic anhydride-modified polyolefin, a peak derived from maleic acid is detected in the vicinity of the wave number of 1760 cm ^-1 and near the wave number 1780 cm ^-1. However, if the acid modification degree is low, the peak may be small and may not be detected. In that case, it can be analyzed by nuclear magnetic resonance spectroscopy.

Specific examples of the polyolefin include polyethylene such as low density polyethylene, medium density polyethylene, high density polyethylene, and linear low density polyethylene; homopolypropylene, block copolymer of polypropylene (for example, block copolymer of propylene and ethylene), polypropylene Polypropylenes such as random copolymers of (for example, random copolymers of propylene and ethylene); ethylene-butene-propylene terpolymers, and the like. Among these polyolefins, polyethylene and polypropylene are preferable.

The cyclic polyolefin is a copolymer of an olefin and a cyclic monomer, and examples of the olefin that is a constituent monomer of the cyclic polyolefin include ethylene, propylene, 4-methyl-1-pentene, butadiene, and isoprene. . Examples of the cyclic monomer that is a constituent monomer of the cyclic polyolefin include cyclic alkenes such as norbornene; specifically, cyclic dienes such as cyclopentadiene, dicyclopentadiene, cyclohexadiene, and norbornadiene. Among these polyolefins, a cyclic alkene is preferable, and norbornene is more preferable.

The acid-modified polyolefin is a polymer obtained by modifying the polyolefin by block polymerization or graft polymerization with an acid component such as carboxylic acid. Examples of the acid component used for modification include carboxylic acids such as maleic acid, acrylic acid, itaconic acid, crotonic acid, maleic anhydride, and itaconic anhydride, or anhydrides thereof.

The acid-modified cyclic polyolefin is obtained by copolymerizing a part of the monomer constituting the cyclic polyolefin in place of the α, β-unsaturated carboxylic acid or its anhydride, or by α, β- It is a polymer obtained by block polymerization or graft polymerization of an unsaturated carboxylic acid or its anhydride. The cyclic polyolefin to be modified with carboxylic acid is the same as described above. The carboxylic acid used for modification is the same as the acid component used for modification of the polyolefin.

Among these resin components, preferred are polyolefins such as polypropylene and carboxylic acid-modified polyolefins; and more preferred are polypropylene and acid-modified polypropylene.

The heat-fusible resin layer 4 may be formed of one kind of resin component alone or may be formed of a blend polymer in which two or more kinds of resin components are combined. Furthermore, the heat-fusible resin layer 4 may be formed of only one layer, but may be formed of two or more layers using the same or different resin components.

In the present invention, it is preferable that a lubricant adheres to the surface of the heat-fusible resin layer from the viewpoint of improving the moldability of the battery packaging material. Although it does not restrict | limit especially as a lubricant, Preferably an amide type lubricant is mentioned. Specific examples of the amide-based lubricant include saturated fatty acid amide, unsaturated fatty acid amide, substituted amide, methylolamide, saturated fatty acid bisamide, unsaturated fatty acid bisamide, and the like. Specific examples of the saturated fatty acid amide include lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, hydroxy stearic acid amide and the like. Specific examples of the unsaturated fatty acid amide include oleic acid amide and erucic acid amide. Specific examples of the substituted amide include N-oleyl palmitic acid amide, N-stearyl stearic acid amide, N-stearyl oleic acid amide, N-oleyl stearic acid amide, N-stearyl erucic acid amide and the like. Specific examples of methylolamide include methylol stearamide. Specific examples of saturated fatty acid bisamides include methylene bis stearamide, ethylene biscapric amide, ethylene bis lauric acid amide, ethylene bis stearic acid amide, ethylene bishydroxy stearic acid amide, ethylene bisbehenic acid amide, hexamethylene bis stearic acid amide. And acid amide, hexamethylene bisbehenic acid amide, hexamethylene hydroxystearic acid amide, N, N′-distearyl adipic acid amide, N, N′-distearyl sebacic acid amide, and the like. Specific examples of unsaturated fatty acid bisamides include ethylene bisoleic acid amide, ethylene biserucic acid amide, hexamethylene bisoleic acid amide, N, N′-dioleyl adipic acid amide, N, N′-dioleyl sebacic acid amide Etc. Specific examples of the fatty acid ester amide include stearoamidoethyl stearate. Specific examples of the aromatic bisamide include m-xylylene bis stearic acid amide, m-xylylene bishydroxy stearic acid amide, N, N′-distearyl isophthalic acid amide and the like. One type of lubricant may be used alone, or two or more types may be used in combination.

When a lubricant is present on the surface of the heat-fusible resin layer 4, the amount of the lubricant is not particularly limited, but is preferably about 3 mg / m ² or more, more preferably in an environment of a temperature of 24 ° C. and a relative humidity of 60%. Is about 4 to 15 mg / m ² , more preferably about 5 to 14 mg / m ² .

A lubricant may be contained in the heat-fusible resin layer 4. Further, the lubricant present on the surface of the heat-fusible resin layer 4 may be one in which a lubricant contained in the resin constituting the heat-fusible resin layer 4 is exuded, or the heat-fusible resin layer. 4 may be obtained by applying a lubricant to the surface.

The thickness of the heat-fusible resin layer 4 can be set according to the presence or absence of the adhesive layer 5, the thickness of the adhesive layer 5, and the like, and particularly if the function as the heat-fusible resin layer is exhibited. Although not limited, the upper limit is, for example, about 100 μm or less, preferably about 85 μm or less, more preferably 60 μm or less, and the lower limit is, for example, about 15 μm or more, preferably 20 μm or more. Examples thereof include about 15 to 100 μm, about 15 to 85 μm, about 15 to 60 μm, about 20 to 100 μm, about 20 to 85 μm, about 20 to 60 μm, and about 15 to 40 μm. In particular, for example, when the thickness of the adhesive layer 5 described later is 10 μm or more, the upper limit of the thickness of the heat-fusible resin layer 4 is preferably about 85 μm or less, more preferably about 60 μm or less. The lower limit is, for example, about 15 μm or more, preferably 20 μm or more, and preferable ranges include about 15 to 85 μm, about 15 to 60 μm, about 20 to 85 μm, and about 20 to 60 μm. For example, when the thickness of the adhesive layer 5 described later is less than 10 μm or when the adhesive layer 5 is not provided, the thickness of the heat-fusible resin layer 4 is preferably about 20 μm or more, more preferably An example is about 35 to 85 μm.

[Adhesive layer 6]
In the battery packaging material of the present invention, the adhesive layer 6 is a layer provided between the barrier layer 3 and the heat-fusible resin layer 4 as necessary in order to firmly bond the barrier layer 3 and the heat-fusible resin layer 4.

The adhesive layer 6 is formed of a resin capable of bonding the barrier layer 3 and the heat-fusible resin layer 4. As the resin used for forming the adhesive layer 6, the same adhesive mechanism and the same types of adhesive components as those exemplified for the adhesive layer 5 can be used. Further, as the resin used for forming the adhesive layer 6, polyolefin resins such as polyolefin, cyclic polyolefin, carboxylic acid-modified polyolefin, carboxylic acid-modified cyclic polyolefin exemplified in the above-mentioned heat-fusible resin layer 4 can also be used. . From the viewpoint of excellent adhesion between the barrier layer 3 and the heat-fusible resin layer 4, the polyolefin is preferably a carboxylic acid-modified polyolefin, and particularly preferably a carboxylic acid-modified polypropylene. That is, the adhesive layer 6 may include a polyolefin skeleton, and preferably includes a polyolefin skeleton. The fact that the adhesive layer 6 contains a polyolefin skeleton can be analyzed by, for example, infrared spectroscopy, gas chromatography mass spectrometry, etc., and the analysis method is not particularly limited. For example, when measuring the infrared spectroscopy at a maleic anhydride-modified polyolefin, a peak derived from maleic acid is detected in the vicinity of the wave number of 1760 cm ^-1 and near the wave number 1780 cm ^-1. However, if the acid modification degree is low, the peak may be small and may not be detected. In that case, it can be analyzed by nuclear magnetic resonance spectroscopy.

Furthermore, from the viewpoint of making the battery packaging material excellent in shape stability after molding while reducing the thickness of the battery packaging material, the adhesive layer 6 is a cured resin composition containing an acid-modified polyolefin and a curing agent. It may be a thing. Preferred examples of the acid-modified polyolefin include the same carboxylic acid-modified polyolefin and carboxylic acid-modified cyclic polyolefin exemplified in the heat-fusible resin layer 4.

Further, the curing agent is not particularly limited as long as it can cure the acid-modified polyolefin. Examples of the curing agent include an epoxy curing agent, a polyfunctional isocyanate curing agent, a carbodiimide curing agent, and an oxazoline curing agent.

The epoxy curing agent is not particularly limited as long as it is a compound having at least one epoxy group. Examples of the epoxy curing agent include epoxy resins such as bisphenol A diglycidyl ether, modified bisphenol A diglycidyl ether, novolac glycidyl ether, glycerin polyglycidyl ether, and polyglycerin polyglycidyl ether.

The polyfunctional isocyanate curing agent is not particularly limited as long as it is a compound having two or more isocyanate groups. Specific examples of the polyfunctional isocyanate-based curing agent include isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), those obtained by polymerizing or nurating these, Examples thereof include mixtures and copolymers with other polymers.

The carbodiimide curing agent is not particularly limited as long as it is a compound having at least one carbodiimide group (—N═C═N—). As the carbodiimide curing agent, a polycarbodiimide compound having at least two carbodiimide groups is preferable.

The oxazoline-based curing agent is not particularly limited as long as it is a compound having an oxazoline skeleton. Specific examples of the oxazoline-based curing agent include Epocros series manufactured by Nippon Shokubai Co., Ltd.

From the viewpoint of improving the adhesion between the barrier layer 3 and the heat-fusible resin layer 4 by the adhesive layer 6, the curing agent may be composed of two or more kinds of compounds.

The content of the curing agent in the resin composition forming the adhesive layer 6 is preferably in the range of about 0.1 to 50% by mass, more preferably in the range of about 0.1 to 30% by mass, More preferably, it is in the range of about 0.1 to 10% by mass.

The thickness of the adhesive layer 6 is not particularly limited as long as it functions as an adhesive layer. However, when the adhesive exemplified in the adhesive layer 5 is used, it is preferably about 1 to 10 μm, more preferably 1 to 1 μm. For example, about 5 μm. Further, when the resin exemplified in the heat-fusible resin layer 4 is used, it is preferably about 2 to 50 μm, more preferably about 10 to 40 μm. In the case of a cured product of an acid-modified polyolefin and a curing agent, it is preferably about 30 μm or less, more preferably about 0.1 to 20 μm, and still more preferably about 0.5 to 5 μm. When the adhesive layer 6 is a cured product of a resin composition containing an acid-modified polyolefin and a curing agent, the adhesive layer 6 can be formed by applying the resin composition and curing it by heating or the like.

[Surface coating layer]
In the battery packaging material of the present invention, a surface coating layer is provided on the outer side of the base material layer 2 (on the side opposite to the barrier layer 3 of the base material layer 2) as necessary for the purpose of improving the design. It may be provided. When the surface coating layer is provided, the surface coating layer is located between the bonding layer 1 b and the base material layer 2.

The surface coating layer can be formed of, for example, polyvinylidene chloride, polyester resin, urethane resin, acrylic resin, epoxy resin, or the like. Of these, the surface coating layer is preferably formed of a two-component curable resin. Examples of the two-component curable resin that forms the surface coating layer include a two-component curable urethane resin, a two-component curable polyester resin, and a two-component curable epoxy resin. Moreover, you may mix | blend an additive with a surface coating layer.

Examples of the additive include fine particles having a particle size of about 0.5 nm to 5 μm. The material of the additive is not particularly limited, and examples thereof include metals, metal oxides, inorganic substances, and organic substances. The shape of the additive is not particularly limited, and examples thereof include a spherical shape, a fiber shape, a plate shape, an indeterminate shape, and a balloon shape. Specific additives include talc, silica, graphite, kaolin, montmorilloid, montmorillonite, synthetic mica, hydrotalcite, silica gel, zeolite, aluminum hydroxide, magnesium hydroxide, zinc oxide, magnesium oxide, aluminum oxide, Neodymium oxide, antimony oxide, titanium oxide, cerium oxide, calcium sulfate, barium sulfate, calcium carbonate, calcium silicate, lithium carbonate, calcium benzoate, calcium oxalate, magnesium stearate, alumina, carbon black, carbon nanotubes, high Melting | fusing point nylon, crosslinked acryl, crosslinked styrene, crosslinked polyethylene, benzoguanamine, gold | metal | money, aluminum, copper, nickel etc. are mentioned. These additives may be used individually by 1 type, and may be used in combination of 2 or more type. Among these additives, silica, barium sulfate, and titanium oxide are preferably used from the viewpoint of dispersion stability and cost. In addition, the surface of the additive may be subjected to various surface treatments such as insulation treatment and high dispersibility treatment.

The content of the additive in the surface coating layer is not particularly limited, but is preferably about 0.05 to 1.0% by mass, more preferably about 0.1 to 0.5% by mass.

The method for forming the surface coating layer is not particularly limited, and examples thereof include a method of applying a two-component curable resin for forming the surface coating layer to the outer surface of the base material layer 2. When blending the additive, the additive may be added to the two-component curable resin, mixed, and then applied.

The thickness of the surface coating layer is not particularly limited as long as it exhibits the above function as the surface coating layer, and for example, it is about 0.5 to 10 μm, preferably about 1 to 5 μm.

3. Method for producing battery packaging material The method for producing the battery packaging material of the present invention is not particularly limited as long as a laminate in which layers having a predetermined composition are laminated is obtained. At least the resin layer 1a and the bonding layer 1b, the base material layer 2, the barrier layer 3, and the heat-fusible resin layer 4 are provided in this order, the bonding layer 1b contains a polyester resin, and the resin layer 1a is an aqueous liquid. The method of using what can peel from the base material layer 2 using is mentioned.

An example of the method for producing the battery packaging material of the present invention is as follows. First, a laminate in which the resin layer 1 a, the bonding layer 1 b, the base material layer 2, the adhesive layer 5, and the barrier layer 3 are laminated in this order (hereinafter also referred to as “laminate A”) is formed. Specifically, in the formation of the laminate A, first, the resin layer 1a, the bonding layer 1b, and the base material layer 2 are laminated by a method such as coextrusion laminating. At this time, as described above, for example, a laminated structure of the resin layer 1a and the bonding layer 1b is used, and the resin layer 1a and the base material layer 2 are adhered to each other through the bonding layer 1b, so that the resin layer 1a A laminate of the bonding layer 1b and the base material layer 2 can be formed. Moreover, you may pressure-bond the adhesive surface side of the joining layer 1b laminated | stacked on the film-form resin layer 1a, respectively, and the film-form base material layer 2, and may obtain a laminated body.

Next, a laminate of the resin layer 1a, the bonding layer 1b, and the base material layer 2 and the barrier layer 3 are laminated. In this lamination, for example, an adhesive used for forming the adhesive layer 5 is applied to the base material layer 2 or the barrier layer 3 whose surface is subjected to chemical conversion treatment as necessary, such as a gravure coating method or a roll coating method. After applying and drying by the method, it can be performed by a dry laminating method in which the barrier layer 3 or the base material layer 2 is laminated and the adhesive layer 5 is cured. Through the above steps, a laminate A in which the resin layer 1a, the bonding layer 1b, the base material layer 2, the adhesive layer 5, and the barrier layer 3 are sequentially laminated is obtained.

Next, the heat-fusible resin layer 4 is laminated on the barrier layer 3 of the laminate A. When the heat-fusible resin layer 4 is directly laminated on the barrier layer 3, the resin component constituting the heat-fusible resin layer 4 is applied to the barrier layer 3 of the laminate A by a gravure coating method or a roll coating method. It may be applied by such a method. When the adhesive layer 6 is provided between the barrier layer 3 and the heat-fusible resin layer 4, for example, (1) the adhesive layer 6 and the heat-fusible resin layer on the barrier layer 3 of the laminate A (2) Separately, a laminate in which the adhesive layer 6 and the heat-fusible resin layer 4 are laminated is formed, and this is formed as a barrier layer of the laminate A (3) A method of extruding or solution-coating an adhesive for forming the adhesive layer 6 on the barrier layer 3 of the laminate A, and drying and baking at a high temperature. And a method of laminating the heat-fusible resin layer 4 previously formed into a sheet (film) on the adhesive layer 6 by a thermal laminating method, and (4) the barrier layer 3 of the laminate A and a sheet in advance. Between the heat-fusible resin layer 4 formed into a film While pouring an adhesive layer 6 which is, and a method of bonding a laminate A and the heat-welding resin layer 4 through the adhesive layer 6 (sandwich lamination method).

The order in which the resin layer 1a and the bonding layer 1b are stacked is not particularly limited. For example, after the base material layer 2 and the barrier layer 3 are stacked, the bonding layer 1b and the resin are formed on the surface of the base material layer 2 side. The layer 1a may be laminated. Moreover, after laminating | stacking the heat-fusible resin layer 4 etc., you may finally laminate | stack the joining layer 1b and the resin layer 1a on the base material layer 2 side, and may obtain the packaging material for batteries.

When providing the surface coating layer, for example, after laminating the surface coating layer on the surface of the base material layer 2 opposite to the barrier layer 3, the bonding layer 1b and the resin layer 1a are placed on the surface coating layer. Laminate. A surface coating layer can be formed by apply | coating said resin which forms a surface coating layer on the surface of the base material layer 2, for example. The order of the step of laminating the barrier layer 3 on the surface of the base material layer 2 and the step of laminating the surface coating layer on the surface of the base material layer 2 are not particularly limited. For example, after forming the surface coating layer on the surface of the base material layer 2, the barrier layer 3 may be formed on the surface of the base material layer 2 opposite to the surface coating layer.

As described above, resin layer 1a / bonding layer 1b / surface coating layer provided as needed / base material layer 2 / adhesive layer 5 provided as needed / one or both surfaces as needed A laminate composed of the barrier layer 3 subjected to the chemical conversion treatment / the adhesive layer 6 provided as necessary / the heat-fusible resin layer 4 is formed. In order to strengthen the adhesiveness of the adhesive layer 5 and the adhesive layer 6 provided as necessary, they may be further subjected to a heat treatment such as a hot roll contact type, a hot air type, a near infrared type or a far infrared type. . An example of such heat treatment conditions is 150 to 250 ° C. for 1 to 5 minutes.

In the battery packaging material of the present invention, each layer constituting the laminate improves or stabilizes film forming properties, lamination processing, suitability for final processing of secondary products (pouching, embossing), and the like as necessary. Therefore, surface activation treatment such as corona treatment, blast treatment, oxidation treatment, ozone treatment may be performed. For example, by performing corona treatment on at least one surface of the base material layer, it is possible to improve or stabilize the film forming property, lamination processing, final product secondary processing suitability, and the like.

Moreover, in this invention, the above-mentioned battery packaging material provided with the resin layer 1a and the joining layer 1b is prepared, and the resin layer 1a is performed by performing the peeling process which peels the resin layer 1a from a laminated body using an aqueous liquid. The battery packaging material from which la is peeled can be produced. About the method of peeling the resin layer 1a from a laminated body, what is necessary is just to make aqueous liquid adhere to the joining layer 1b as mentioned above.

Furthermore, in the method for producing a battery packaging material of the present invention, after the peeling step, a printing step of performing printing with ink on the surface of the laminate constituting the battery packaging material on the substrate layer 2 side. Furthermore, you may provide. Thereby, the packaging material for batteries by which the surface by the side of the base material layer 2 was printed can be manufactured suitably. That is, the battery packaging material of the present invention can be suitably used for applications in which the resin layer 1a is peeled off using an aqueous liquid, and the surface on the base material layer 2 side is printed with ink.

As will be described later, the step of peeling the resin layer 1a from the battery packaging material and the printing step may be performed in the battery manufacturing process using the battery packaging material. The battery packaging material of the present invention including the resin layer 1a and the bonding layer 1b is subjected to molding by a mold and then subjected to the peeling step and the printing step, thereby improving the moldability improvement effect by the resin layer 1a and the bonding layer 1b. It can enjoy suitably. For example, printing may be performed on the outside of the battery from the viewpoint of battery identification. In the battery packaging material of the present invention, until printing is performed, the deterioration of the characteristics of the surface of the battery packaging material on the substrate layer 2 side is effectively suppressed, and an aqueous liquid is used when printing is performed. By peeling off the resin layer 1a from the laminate, the surface of the battery packaging material that becomes the printing surface can be easily exposed, and the surface of the base material layer 2 or the surface coating layer can be exposed to ink. It can also be suitably applied to applications where printing is performed. Further, the battery packaging material of the present invention including the resin layer 1a and the bonding layer 1b is subjected to molding using a mold, and then the resin layer 1a is separated from the laminate using an aqueous liquid, whereby the resin layer 1a becomes a barrier. The effect of suppressing the pinhole of the layer 3 and the effect of suppressing the surface of the base material layer 2 and the surface coating layer from being damaged by the mold can be suitably enjoyed. Further, when the heat-fusible resin layer 4 is heat-sealed using the battery packaging material of the present invention including the resin layer 1a and the bonding layer 1b, the base material layer 2 and the surface coating layer are deteriorated due to high temperature and high pressure. Can be effectively suppressed by the protection by the resin layer 1a. Note that the timing and purpose of peeling the resin layer 1a are not limited to these.

The printing method using ink is not particularly limited, and for example, pad printing and ink jet printing are suitable. Pad printing is a printing method as follows. First, ink is poured into a concave portion of a flat plate in which a pattern to be printed is etched. Next, the silicon pad is pressed from above the concave portion to transfer the ink to the silicon pad. Next, the ink transferred to the surface of the silicon pad is transferred to the printing object to form a print on the printing object. In such pad printing, since the ink is transferred to the object to be printed using an elastic silicon pad or the like, it is easy to print on the surface of the battery packaging material after molding, and the battery element is made of the battery packaging material. After sealing, the battery can be printed. In addition, ink jet printing has similar advantages.

4). Application of Battery Packaging Material The battery packaging material of the present invention is used in a package for sealing and housing battery elements such as a positive electrode, a negative electrode, and an electrolyte. That is, a battery element including at least a positive electrode, a negative electrode, and an electrolyte can be accommodated in a package formed of the battery packaging material of the present invention to obtain a battery.

Specifically, a battery element including at least a positive electrode, a negative electrode, and an electrolyte is formed using the battery packaging material of the present invention, with the metal terminals connected to each of the positive electrode and the negative electrode protruding outward. By covering the periphery of the element so that a flange portion (region where the heat-fusible resin layers are in contact with each other) can be formed, and heat-sealing the heat-fusible resin layers of the flange portion to seal the battery A battery using the packaging material is provided. In addition, when accommodating a battery element using the battery packaging material of the present invention, the battery packaging material of the present invention is used so that the heat-fusible resin portion is on the inner side (surface in contact with the battery element). When the heat-fusible resin layer 4 is heat-sealed using the battery packaging material of the present invention including the resin layer 1a and the bonding layer 1b, deterioration of the base material layer 2 and the surface coating layer due to high temperature and high pressure It can suppress effectively by the protection by the resin layer 1a. In the battery packaging material of the present invention, the resin layer 1a can be peeled after the heat-fusible resin layer 4 is heat-sealed.

The package formed by the battery packaging material of the present invention can be formed by bending one battery packaging material and heat-sealing the edges of the opposing heat-fusible resin layers, It can also be formed by stacking two battery packaging materials so that the heat-fusible resin layers face each other and heat-sealing the edges. When two battery packaging materials are used, the battery packaging material of the present invention may be used for only one of them, or the battery packaging material of the present invention may be used for both. Furthermore, the resin layer 1a may be peeled first from one of the battery packaging materials according to the desired timing at which the surface of the base material layer 2 is desired to be protected, or the resin layer may be removed from both battery packaging materials at the same timing. 1a may be peeled off.

Furthermore, the battery of the present invention may be one in which the resin layer 1a is peeled off. Such a battery includes, for example, a step of containing a battery element including at least a positive electrode, a negative electrode, and an electrolyte in a package formed of the battery packaging material of the present invention, and an aqueous liquid. It can manufacture by the method provided with the peeling process which peels the layer 1a from a package. About the specific example of the method of peeling the resin layer 1a from a laminated body, it is the same as that of the above-mentioned method.

Furthermore, the method for producing a battery of the present invention further includes a printing step of performing printing with ink on the surface on the base material layer 2 side of the package constituting the battery packaging material after the peeling step. Also good. Thereby, the battery by which the printing was performed on the outer side of a battery can be manufactured suitably. In particular, in the battery manufacturing process, by providing a printing process immediately after the peeling process, the outer surface (the resin layer 1a is peeled off) by the resin layer 1a until immediately before the printing process when manufacturing the battery and the battery packaging material. After that, it is possible to suitably perform printing on the battery in which the deterioration of the characteristics of the base material layer 2 and the surface coating layer (which is the outer surface of the battery) is effectively suppressed.

In the present invention, the resin layer 1a can be peeled off, but may be used as it is as a battery from which the resin layer 1a is not peeled off.

When the resin layer 1a is peeled from the battery including the resin layer 1a and the bonding layer 1b, the resin layer 1a can be peeled at a desired timing. Since the heat dissipation is improved by removing the resin layer 1a from the battery, when the improvement of the heat dissipation of the battery is required, the resin layer 1a is preferably used as a battery having an improved heat dissipation by peeling off the resin layer 1a. Can do. Moreover, since the thickness of the battery can be reduced by peeling the resin layer 1a from the battery, when it is required to make the battery thinner, the battery having a reduced thickness by peeling the resin layer 1a. It can be preferably used. The timing and purpose of peeling the resin layer 1a from the battery are not limited to these. As for the method of peeling the resin layer 1a from the battery, an aqueous liquid may be attached to the bonding layer 1b as described above.

The battery packaging material of the present invention may be used for either a primary battery or a secondary battery, but is preferably a secondary battery. The type of secondary battery to which the battery packaging material of the present invention is applied is not particularly limited. For example, a lithium ion battery, a lithium ion polymer battery, a lead storage battery, a nickel-hydrogen storage battery, a nickel-cadmium storage battery, a nickel- Examples include iron storage batteries, nickel / zinc storage batteries, silver oxide / zinc storage batteries, metal-air batteries, multivalent cation batteries, capacitors, capacitors, and the like. Among these secondary batteries, lithium ion batteries and lithium ion polymer batteries are suitable applications for the battery packaging material of the present invention.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the examples.

<Manufacture of battery packaging materials>
Example 1
A polyethylene terephthalate film and a nylon film were laminated by coextrusion to prepare a biaxially stretched laminated film. In the laminated film, a joint formed of a polyester resin (poly (tetramethylene ether) glycol-based resin) between the biaxially stretched polyethylene terephthalate film (thickness 5 μm) and the biaxially stretched nylon film (thickness 20 μm). Bonded by layers (1 μm thick). The laminated film is a laminate in which a resin layer / bonding layer / base material layer is sequentially laminated, and is biaxially stretched after co-extrusion of resin layer / bonding layer / base material layer. In addition, the laminated film contains an ultraviolet absorber (TINUVIN 326), a light stabilizer (TINUVIN 770), and an antioxidant (Irganox 1330, Irganox 1098, Irganox 1010). Next, an aluminum alloy foil (thickness 40 μm) as a barrier layer was laminated on the surface of the base material layer by a dry laminating method. Specifically, a two-component urethane adhesive (a polyol compound and an aromatic isocyanate compound) is applied to one surface of an aluminum alloy foil having an acid-resistant film formed on the surface, and the adhesive is applied to the surface of the aluminum alloy foil. A layer (thickness 3 μm) was formed. Next, after laminating the adhesive layer and the base material layer on the barrier layer by the dry laminating method, the resin layer / bonding layer / base material layer / adhesive layer / barrier layer are laminated in order by performing an aging treatment. A laminate was prepared. The aluminum foil used as the barrier layer is provided with an acid resistant film containing cerium oxide and phosphate.

Next, an adhesive composed of a non-crystalline polyolefin resin having a carboxyl group and a polyfunctional isocyanate compound (with a thickness of 2 μm after curing) is formed on the barrier layer of the obtained laminate (the surface of the acid-resistant film). The adhesive layer / heat-sealable resin is applied onto the barrier layer by coating and drying the barrier layer side of the resulting laminate and an unstretched polypropylene film (thickness 80 μm) through a hot roll and bonding them. The layers were laminated. Next, by aging the obtained laminate, biaxially stretched polyethylene terephthalate film (5 μm) / bonding layer (1 μm) / biaxially stretched nylon film (20 μm) / adhesive layer (3 μm) / barrier layer (40 μm) ) / Adhesive layer (2 μm) / unstretched polypropylene film (80 μm) were laminated in this order to obtain a battery packaging material. Table 1 shows the layer structure of the battery packaging material.

(Comparative Example 1)
As a laminate of a resin layer, a bonding layer, and a base material layer, a polyethylene terephthalate film (thickness 12 μm) as a resin layer and a stretched nylon film (thickness 15 μm) as a base material layer are a two-component urethane adhesive ( A material bonded with a polyol compound and an aromatic isocyanate compound (thickness: 3 μm) was prepared. Next, in the same manner as in Example 1, an aluminum alloy foil (thickness 40 μm) as a barrier layer was laminated on the surface of the base material layer by a dry laminating method, and resin layer / bonding layer / base material layer / adhesion A laminate in which the agent layer / barrier layer was sequentially laminated was produced. The acid-resistant film formed on the surface of the aluminum alloy foil is roll-coated with a treatment liquid composed of a phenol resin, a chromium fluoride compound, and phosphoric acid so that the coating amount of chromium is 10 mg / m ² (dry mass). It is formed by applying and baking on both surfaces of an aluminum alloy foil by the method. Next, an acid-modified polypropylene (thickness: 40 μm) as an adhesive layer and a polypropylene (thickness: 40 μm) as a heat-fusible resin layer are laminated by coextrusion laminating method to obtain a resin layer / bonding layer / base material layer. A battery packaging material in which / adhesive layer / barrier layer / adhesive layer / heat-fusible resin layer was laminated in this order was obtained. The specific laminated structure is shown in Table 1.

(Comparative Example 2)
As a laminate of a resin layer, a bonding layer, and a base material layer, a polyethylene terephthalate film (thickness 12 μm) as a resin layer and a stretched nylon film (thickness 15 μm) as a base material layer are a two-component urethane adhesive What was adhered by (polyol compound and aromatic isocyanate compound, thickness 3 μm) was prepared. Next, in the same manner as in Example 1, an aluminum alloy foil (thickness 40 μm) as a barrier layer was laminated on the surface of the base material layer by a dry laminating method, and resin layer / bonding layer / base material layer / adhesion A laminate in which the agent layer / barrier layer was sequentially laminated was produced. The acid-resistant film formed on the surface of the aluminum alloy foil is the same as in Comparative Example 1. Next, an adhesive composed of a non-crystalline polyolefin resin having a carboxyl group and a polyfunctional isocyanate compound (thickness after curing is 3 μm) on the barrier layer (surface of the acid-resistant film) of the obtained laminate. By applying and drying, the barrier layer side of the obtained laminate and an unstretched random polypropylene film (thickness 80 μm) are passed between hot rolls and bonded to each other, whereby a resin layer / bonding layer / base material layer / A battery packaging material in which an adhesive layer / barrier layer / adhesive layer / heat-fusible resin layer was laminated in order was obtained. The specific laminated structure is shown in Table 1.

(Comparative Example 3)
An aluminum alloy foil (thickness 40 μm) as a barrier layer is laminated on the surface of a stretched nylon film (thickness 25 μm) as a base material layer by a dry laminating method, and the base material layer / adhesive layer / barrier layer in this order. A laminated body was produced. The acid-resistant film formed on the surface of the aluminum alloy foil is the same as in Comparative Example 1. Next, in the same manner as in Comparative Example 1, acid-modified polypropylene (thickness: 23 μm) as an adhesive layer and polypropylene (thickness: 23 μm) as a heat-fusible resin layer were laminated by coextrusion laminating. Next, the joining layer side of the resin layer obtained by laminating a polyethylene terephthalate film (thickness 50 μm) as a resin layer and a joining layer (thickness 1 μm) composed of a silicone resin (silicone elastomer), and the laminate created above The base material layer side of the body was bonded to obtain a battery packaging material in which a resin layer / bonding layer / base material layer / adhesive layer / barrier layer / adhesive layer / heat-sealable resin layer were sequentially laminated. The specific laminated structure is shown in Table 1.

(Comparative Example 4)
In Comparative Example 3, the base layer / adhesive layer / barrier layer / adhesive layer / heat-sealable resin was the same as Comparative Example 3 except that the resin layer and the bonding layer were not laminated on the base layer. A battery packaging material in which layers were sequentially laminated was obtained. The specific laminated structure is shown in Table 1.

<Analysis of UV absorber, light stabilizer and antioxidant>
About 10 g was physically peeled between the base material layer and the barrier layer of the battery packaging material of Example 1 without using a solvent. Next, in order to increase the extraction efficiency of the additive component in each layer, the laminate of the resin layer, the bonding layer, and the base material layer is wound and extracted with a stainless steel mesh so that the adhesion between the layers is reduced. It was. Next, using chloroform as the extraction solvent, Soxhlet extraction is performed for 10 hours to extract the additive components. After distilling off the solvent, it was dissolved in a measurement solvent and subjected to analysis. In GC / MS, Irganox 1330, Irganox 1098, TINUVIN 326, and TINUVIN 770 were detected. Irganox 1010 was detected by HPLC.

[Analysis by GC / MS (Gas Chromatograph Mass Spectrometry)]
(Apparatus, measurement conditions)
Apparatus: Gas chromatograph manufactured by Shimadzu Corporation GC / MS-QP2010 Ultra
Column: Ultra ALLOY ⁺ -1 (MS / HT) manufactured by Frontier Lab, df = 0.15 μm, 0.25 mm I.D. D. × 15m
Column temperature: 80-390 ° C. 11 ° C./min hold
Carrier: He 1.1mL / min
Injection method: Split method Injection volume: 1 μL
Ionization method: EI method 70 eV
Sample preparation: Dissolved in 2 mL of chloroform / methanol (1/1; v / v) mixed solvent

[Analysis by HPLC (liquid chromatograph)]
(Apparatus, measurement conditions)
Apparatus: HPLC PU-2085 type column manufactured by JASCO Corporation: Unison UK-C18 3 μm, 4.6 mm I.D. D. × 100mm
Column temperature: 80-390 ° C. 11 ° C./min hold
Carrier: He 1.1mL / min
Injection method: Split method 1:12
Injection volume: 1 μL
Quantitative method: Absolute calibration curve method Sample: Dissolved in 2 mL of chloroform / methanol (1/1; v / v) mixed solvent

<Measurement of content of ultraviolet absorber, light stabilizer and antioxidant>
About the battery packaging material of Example 1, in the same manner as in the above-described <Analysis of UV absorber, light stabilizer and antioxidant>, from the laminate of the resin layer, the bonding layer, and the base material layer, an additive component Was extracted, and a sample dissolved in the measurement solvent was prepared. About the obtained sample, content of a ultraviolet absorber, a light stabilizer, and antioxidant was measured with the following gas chromatographs (GC) and liquid chromatographs (HPLC). As a result, it was confirmed by HPLC that Irganox 1098 contained 370 ppm, TINUVIN 326 contained 60 ppm, Irganox 1010 contained 30 ppm, and Irganox 1330 contained 130 ppm. In addition, it was confirmed by GC that TINUVIN 770 was contained at 140 ppm.

[Measurement of content by GC (gas chromatograph)]
(Apparatus, measurement conditions)
Apparatus: Gas chromatograph GC-2010 manufactured by Shimadzu Corporation
Column: MXT-1 manufactured by Shimadzu Corporation, df = 0.15 μm, 0.25 mm I.D. D. × 15m
Column temperature: 80-390 ° C. 11 ° C./min hold
Carrier: He 1.1mL / min
Injection method: Split method 1:12
Injection volume: 1 μL
Quantitative method: Absolute calibration curve method Sample: Dissolved in 2 mL of chloroform / methanol (1/1; v / v) mixed solvent

[Measurement of content by HPLC (liquid chromatograph)]
(Apparatus, measurement conditions)
Apparatus: HPLC PU-2085 type column manufactured by JASCO Corporation: Unison UK-C18 3 μm, 4.6 mm I.D. D. × 100mm
Column temperature: 80-390 ° C. 11 ° C./min hold
Carrier: He 1.1mL / min
Injection method: Split method 1:12
Injection volume: 1 μL
Quantitative method: Absolute calibration curve method Sample: Dissolved in 2 mL of chloroform / methanol (1/1; v / v) mixed solvent

<Measurement of peel strength with water attached>
For each battery packaging material obtained in Example 1 and Comparative Examples 1 to 3, the peel strength of the polyethylene terephthalate film in a state where water was adhered to the surface of the polyethylene terephthalate film located on the outermost surface. Was measured by the following measurement method. The battery packaging material was cut into a rectangular shape of 100 mm (MD) × 15 mm (TD) to obtain a test sample. In an environment of a temperature of 25 ° C., a relative humidity of 50%, and an atmospheric pressure (1 atm), first, 35% hydrochloric acid is adhered to the end portions of the resin layer and the bonding layer of the test sample, as shown in the schematic diagram of FIG. The resin layer was peeled about 30 mm in the MD direction. The hydrochloric acid adhering to the test sample was wiped off and dried as it was. Next, distilled water (W) was adhered to the portion where the resin layer was peeled off (bonding layer 1b between the resin layer and the base layer side surface) using a dropper. At this time, distilled water (W) was adhered to the entire boundary in the TD direction at the boundary between the resin layer and the substrate layer side surface. Next, the resin layer 1a was peeled from the surface of the base material layer using a tensile tester (Autograph manufactured by Shimadzu Corporation) under the measurement conditions of a distance between chucks of 50 mm, a peeling speed of 50 mm / min, and a peeling angle of 180 °. The peel strength when the distance between chucks reached 57 mm was defined as the peel strength (N / 15 mm) with distilled water attached. The results are shown in Table 1. In addition, the minimum of the detection limit value of the tensile tester used for the measurement of peel strength is 0.3 N / 15 mm.

<Measurement of peel strength without water adhering>
Except that the distilled water is not attached to the part where the resin layer is peeled off (bonding layer 1b between the resin layer and the substrate layer side surface) using the dropper, the above <Peeling with the water attached The peel strength when the resin layer is peeled off from the surface of the base material layer under the same measurement conditions as in the measurement of strength and the chuck-to-chuck distance reaches 57 mm is the peel strength (N / 15 mm) with no water attached. It was. The results are shown in Table 1.

<Evaluation of formability>
Each battery packaging material obtained above was cut into 150 mm (TD) × 100 mm (MD) strips, which were used as test samples. The MD of the battery packaging material corresponds to the rolling direction of the aluminum alloy foil, and the TD of the battery packaging material corresponds to the TD of the aluminum alloy foil. The rolling direction of the aluminum alloy foil can be confirmed by the rolling marks of the aluminum alloy foil. The mold is a rectangular male mold of 30 mm (MD) × 50 mm (TD) (the surface is defined in Table 2 of Comparative Surface Roughness Standard Pieces for Reference JIS B 0659-1: 2002 Annex 1) The maximum height roughness (nominal value of Rz is 1.6 μm), the female mold with a clearance of 0.5 mm from this male mold (the surface is JIS B 0659-1: 2002 Annex 1 (reference) comparison) A straight mold having a maximum height roughness (Rz nominal value of 3.2 μm) defined in Table 2 of the surface roughness standard piece for use was used. The test sample was placed on the female mold so that the heat-fusible resin layer side was positioned on the male mold side. Each of the test samples was pressed with a surface pressure of 0.1 MPa so as to have a molding depth of 5.0 mm, and cold-molded (drawn one-step molding). The test samples of Example 1 and Comparative Examples 1 to 3 are molded with the resin layer and the bonding layer laminated. About the sample after cold forming, it was confirmed visually whether the wrinkle was formed in the forming part. The results are shown in Table 1.

<Evaluation of printability on substrate surface>
The design was printed by pad printing on the surface of the base material layer of the test sample from which the resin layer was peeled in the above <Measurement of peel strength with water attached>. In Comparative Example 4, since the resin layer and the bonding layer were not provided, the design was printed on the surface of the base material layer as it was by pad printing. The pad printer used was SPACE PAD 6GX manufactured by Mishima Corporation, and the ink used was UV ink PJU-A black manufactured by Navitas Co., Ltd. Further, the ink was cured by irradiating UV for 30 seconds from a distance of 10 cm at an ultraviolet wavelength of 254 nm with a handy UV lamp SUV-4 manufactured by ASONE. The printability was evaluated according to the following criteria. The printability measurement was performed in an environment of 24 ° C. and a relative humidity of 50%. The results are shown in Table 1.
A: Print missing is 2.5% or less B Print missing is more than 2.5% and 5% or less C: Print missing is more than 2.5%

<Evaluation of deterioration of base material layer during heat fusion>
About each battery packaging material obtained in Example 1 and Comparative Examples 1 to 4, the heat-fusible resin layers were folded in two so as to face each other, and a heated seal bar (metal plate) was used. It was inserted from the base material layer side, and the heat-fusible resin layers were heat-sealed. The heat sealing conditions were a seal bar heating temperature of 220 ° C., a surface pressure of 1.0 MPa, and a time of 1 second. The base material layer was observed from the top of the resin layer of each battery packaging material after heat fusion, and evaluated according to the following criteria. The results are shown in Table 1.
A: No melting, deformation, discoloration, foaming or the like is observed in the base material layer C: Melting, deformation, discoloration, foaming or the like is observed in the base material layer

<Evaluation of releasability of resin layer after heat sealing>
Using each battery packaging material after heat fusion obtained in <Evaluation of degradation of base material layer during heat fusion> as a test sample, <Measurement of peel strength with water attached> In the same manner as above, in an environment of a temperature of 25 ° C., a relative humidity of 50%, and an atmospheric pressure (1 atm), first, 35% hydrochloric acid is adhered to the end portions of the resin layer and the bonding layer of the test sample, and the direction of MD The resin layer was peeled off by about 30 mm. The hydrochloric acid adhering to the test sample was wiped off and dried as it was. Next, distilled water (W) was adhered to the portion where the resin layer was peeled off (bonding layer 1b between the resin layer and the base layer side surface) using a dropper. At this time, distilled water (W) was adhered to the entire boundary in the TD direction at the boundary between the resin layer and the substrate layer side surface. Next, for each test sample, Table 1 shows whether the resin layer could be peeled from the base material layer by pinching the resin layer with a finger.

<Evaluation of peelability of resin layer before heat sealing>
Except that each battery packaging material before heat fusion was used as a test sample, in the same manner as in the above <Evaluation of releasability of resin layer after heat fusion>, peeling of the resin layer before heat fusion Sex was evaluated. The results are shown in Table 1.

In the laminated structure shown in Table 1, PET is a polyethylene terephthalate layer, Ny is a nylon layer, AD is a bonding layer, DL is an adhesive layer formed by a dry lamination method, ALM is an aluminum alloy foil, PPa is an acid-modified polypropylene layer, CPP means an unstretched polypropylene layer and PP means a polypropylene layer. Further, the numerical value described after each layer of the laminated structure means a thickness (μm), for example, “PET (12)” means “a polyethylene terephthalate layer having a thickness of 12 μm”. Moreover, the result that peeling strength is 0.3 N / 15 mm or less means that peeling strength was below a detection limit value.

Example 1 in which a bonding layer containing a polyester resin was provided on the resin layer had high peel strength when no water was attached, and very low peel strength when water was attached. Therefore, the resin layer could be easily peeled off with water attached. Moreover, even if it molded in the state which laminated | stacked the resin layer and the joining layer, there was no wrinkle after shaping | molding and the external appearance was favorable. Furthermore, even when heat sealing is performed in a state where the resin layer and the bonding layer are laminated, no deterioration is observed in the base material layer, and water is adhered to the end surfaces of the resin layer and the bonding layer before and after the heat bonding. The resin layer could be easily peeled off. From this result, if the peel strength when peeling the resin layer from the laminate using an aqueous liquid is 1.0 N / 15 mm or less, the resin layer can be suitably peeled, and 0.5 N / 15 mm or less. If it exists, it can be said that a resin layer can be peeled off more suitably.

On the other hand, Comparative Examples 1 and 2 using urethane resin as the bonding layer had high peel strength in a state where water was not attached and peel strength in a state where water was attached. Therefore, it was difficult to peel off the resin layer even when water was attached. In addition, there was no wrinkle after molding even when molded in a state where the resin layer and the bonding layer were laminated, and no deterioration was observed even after heat sealing. The resin layer could not be peeled even when water was attached to the end face. This is considered to be because the peel strength of the urethane resin is further increased by the heat of heat fusion, and is more difficult to peel.

Comparative Example 3 using a silicone resin as the bonding layer had low peel strength in the state where water was not attached and peel strength in the state where water was attached. For this reason, the resin layer can be easily peeled off even when water is not attached, and there is a flaw when the protective layer is laminated, and the appearance is poor.

In Comparative Example 4 in which the protective layer was not provided, the base layer was melted and the nylon resin adhered to the seal bar used for the thermal fusion by performing the thermal fusion.

DESCRIPTION OF SYMBOLS 1 ... Protective layer 1a ... Resin layer 1b ... Bonding layer 2 ... Base material layer 3 ... Barrier layer 4 ... Heat-fusible resin layer 5 ... Adhesive layer 6 ... Adhesive layer 10 ... Battery packaging material W ... Water

Claims

At least, it is composed of a laminate comprising a resin layer, a bonding layer, a base material layer, a barrier layer, and a heat-fusible resin layer in this order,
The bonding layer includes a polyester resin,
The battery packaging material, wherein the resin layer is peelable from the laminate using an aqueous liquid.
In an environment of a temperature of 25 ° C., a relative humidity of 50%, and atmospheric pressure, the peel strength when the resin layer is peeled from the laminate without water adhering to the bonding layer is 2.0 N / 15 mm or more. ,And,
The peel strength when peeling the resin layer from the laminate using the aqueous liquid in an environment of temperature 25 ° C., relative humidity 50%, and atmospheric pressure is 1.0 N / 15 mm or less,
The battery packaging material according to claim 1, wherein the aqueous liquid is water.
The battery packaging material according to claim 1 or 2, wherein a lubricant is present on the surface of the laminate on the resin layer side.
The battery packaging material according to any one of claims 1 to 3, wherein an ultraviolet absorber is contained in at least one of the resin layer, the bonding layer, and the base material layer.
The battery packaging material according to claim 4, wherein the ultraviolet absorbent is a benzotriazole ultraviolet absorbent.
The battery packaging material according to any one of claims 1 to 5, wherein a light stabilizer is contained in at least one of the resin layer, the bonding layer, and the base material layer.
The battery packaging material according to claim 6, wherein the light stabilizer is a hindered amine light stabilizer.
At least a step of obtaining a laminate by laminating a resin layer, a bonding layer, a base material layer, a barrier layer, and a heat-fusible resin layer in this order;
The manufacturing method of the packaging material for batteries using the said joining layer contains the polyester resin and the said resin layer can peel from the said laminated body using an aqueous liquid.
A battery in which a battery element including at least a positive electrode, a negative electrode, and an electrolyte is accommodated in a package formed of the battery packaging material according to any one of claims 1 to 7.