JPWO2017179636A1 - Battery packaging material, manufacturing method thereof, and battery - Google Patents

Abstract

Provided is a battery packaging material having high moldability and excellent battery continuous productivity. It consists of a laminate having at least a base material layer, a barrier layer, and a heat-fusible resin layer in this order. At least the surface of the laminate on the base material layer side contains a lubricant, and the laminate A battery packaging material in which the total amount of lubricant on the surface of the substrate on the side of the base layer and the amount of lubricant on the surface of the heat-fusible resin layer of the laminate is 15 mg / m 2 or more and 60 mg / m 2 or less.

Description

  The present invention relates to a battery packaging material, a method for producing the same, and a battery.

  Conventionally, various types of batteries have been developed. In any battery, a packaging material is an indispensable member for sealing battery elements such as electrodes and electrolytes. Conventionally, metal packaging materials have been widely used for battery packaging, but in recent years, with the increasing performance of electric vehicles, hybrid electric vehicles, personal computers, cameras, mobile phones, etc., batteries are required to have various shapes. At the same time, there is a demand for reduction in thickness and weight. However, metal battery packaging materials that have been widely used in the past have the disadvantages that it is difficult to follow the diversification of shapes and that there is a limit to weight reduction.

  Therefore, as a battery packaging material that can be easily processed into various shapes and can be made thinner and lighter, a film-like structure in which a base layer / adhesive layer / barrier layer / heat-sealable resin layer are sequentially laminated. A laminated body has been proposed (see, for example, Patent Document 1). Such a film-shaped battery packaging material is formed so that the battery element can be sealed by causing the heat-fusible resin layers to face each other and heat-sealing the peripheral edge portion by heat sealing.

  In the battery packaging material, when the battery element is encapsulated, it is molded with a mold to form a space for accommodating the battery element. At the time of molding, there is a problem that cracks and pinholes are likely to occur in the barrier layer at the flange portion of the mold due to the battery packaging material being stretched. In order to solve such a problem, the surface of the heat-fusible resin layer of the battery packaging material is coated with a lubricant, or the lubricant is blended into the heat-fusible resin layer to cause the surface to bleed out. A method for improving the slipperiness of battery packaging materials is known. By adopting such a method, the battery packaging material is easily drawn into the mold during molding, and cracks and pinholes in the battery packaging material can be suppressed.

JP 2008-287971 A

  If the amount of the lubricant present on the surface of the heat-fusible resin layer of the battery packaging material is too large, there is a problem that the lubricant adheres to the mold and contaminates the mold as a lump. If another battery packaging material is molded while the mold is contaminated, the lump of lubricant adhering to the mold adheres to the surface of the battery packaging material and is directly used for heat fusion of the heat-fusible resin layer. Is done. In this case, when the heat-fusible resin layer is heat-sealed, the melted portion of the portion to which the lubricant has adhered becomes non-uniform, resulting in poor sealing. In order to prevent this, it becomes necessary to increase the frequency of cleaning for removing the lubricant adhering to the mold, and there is a problem that the continuous productivity of the battery is lowered.

  On the other hand, if the amount of the lubricant present on the surface of the battery packaging material is too small, the slipping property of the battery packaging material is lowered, which causes a problem that the moldability of the battery packaging material is lowered.

  Under such circumstances, a main object of the present invention is to provide a battery packaging material having high moldability and excellent battery continuous productivity.

The present inventor has intensively studied to solve the above problems. As a result, it is composed of a laminate having at least a base material layer, a barrier layer, and a heat-fusible resin layer in this order, and at least the surface of the laminate on the base material layer side has a lubricant. A battery in which the total amount of lubricant on the substrate layer side surface of the laminate and the amount of lubricant on the surface of the heat-fusible resin layer of the laminate is 15 mg / m ² or more and 60 mg / m ² or less. It has been found that the packaging material for batteries has a high moldability, is excellent in continuous productivity of the battery, and becomes a battery packaging material suitable for battery production. The present invention has been completed by further studies based on these findings.

That is, this invention provides the battery packaging material and battery of the aspect hung up below.
Item 1. It consists of a laminate having at least a base material layer, a barrier layer, and a heat-fusible resin layer in this order,
At least on the surface of the laminate on the side of the base material layer, a lubricant is present,
The total of the amount of lubricant on the surface of the laminate on the substrate layer side and the amount of lubricant on the surface of the heat-fusible resin layer of the laminate is 15 mg / m ² or more and 60 mg / m ² or less. Packaging materials.
Item 2. Item ^2. The battery packaging material according to Item 1, wherein the amount of lubricant present on the surface of the laminate on the substrate layer side is 3 mg / m ² or more and 15 mg / m ² or less.
Item 3. Item 3. The battery packaging material according to Item 1 or 2, wherein the amount of lubricant present on the surface of the heat-fusible resin layer of the laminate is 10 mg / m ² or more and 50 mg / m ² or less.
Item 4. Item 4. The battery packaging material according to any one of Items 1 to 3, wherein the base material layer has at least one of a layer formed of polyester and a layer formed of polyamide.
Item 5. Item 5. The battery packaging material according to any one of Items 1 to 4, further comprising a surface coating layer on the opposite side of the base material layer from the barrier layer.
Item 6. Item 6. The battery packaging material according to any one of Items 1 to 5, wherein the lubricant contains an amide-based lubricant.
Item 7. Item 7. The battery packaging material according to any one of Items 1 to 6, wherein the heat-fusible resin layer includes a layer formed of polyolefin.
Item 8. Item 8. The battery packaging material according to any one of Items 1 to 7, wherein a base coating layer is provided on at least one surface of the barrier layer.
Item 9. Item 9. The battery packaging material according to any one of Items 1 to 8, which is a packaging material for a secondary battery.
Item 10. A battery in which a battery element including at least a positive electrode, a negative electrode, and an electrolyte is housed in a package formed of the battery packaging material according to any one of Items 1 to 9.
Item 11. It includes a step of laminating at least a base material layer, a barrier layer, and a heat-fusible resin layer in this order,
At least a lubricant is present on the surface of the laminate on the substrate layer side, and the amount of lubricant on the surface of the laminate on the substrate layer side and the surface of the heat-fusible resin layer of the laminate are A method for producing a battery packaging material, wherein the total amount of lubricant is 15 mg / m ² or more and 60 mg / m ² or less.
Item 12. Item 12. The method for producing a battery packaging material according to Item 11, further comprising a step of subjecting at least one surface of the base material layer to corona treatment.

  According to the present invention, it is possible to provide a battery packaging material having high moldability and excellent battery continuous productivity.

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 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 the crystal grain and 2nd phase particle in the thickness direction of an aluminum alloy foil layer.

The battery packaging material of the present invention comprises a laminate having at least a base material layer, a barrier layer, and a heat-fusible resin layer in this order, and at least on the surface of the laminate on the base material layer side, A lubricant is present, and the total amount of lubricant on the surface of the laminate on the base material layer side and the amount of lubricant on the surface of the heat-fusible resin layer of the laminate is 15 mg / m ² or more and 60 mg / m ² or less. It is characterized by being.
Hereinafter, the battery packaging material of the present invention will be described in detail.

1. Laminated Structure of Battery Packaging Material As shown in FIG. 1, the battery packaging material of the present invention comprises a laminate having at least a base material layer 1, a barrier layer 3, and a heat-fusible resin layer 4 in this order. . In the battery packaging material of the present invention, the base material layer 1 is the outermost layer side, 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.

  As shown in FIG. 2, the battery packaging material 10 of the present invention is provided with an adhesive layer 2 between the base material layer 1 and the barrier layer 3 as necessary for the purpose of enhancing the adhesion. It may be. Further, as shown in FIG. 3, the battery packaging material 10 of the present invention is provided with an adhesive layer between the barrier layer 3 and the heat-fusible resin layer 4 as needed for the purpose of enhancing the adhesion between them. 5 may be provided. Moreover, as shown in FIG. 4, the surface coating layer 6 may be formed in the surface at the side of the base material layer 1. As shown in FIG.

  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, about 150 μm or less, preferably about 120 μm or less, more preferably about 50 μm to 100 μm, and still more preferably about 50 μm to 80 μm.

In the battery packaging material 10 of the present invention, a lubricant is present on the surface of the base material layer 1, and the amount of the lubricant on the base material layer side of the laminate constituting the battery packaging material 10 and the lamination The total amount of lubricant on the surface of the heat-fusible resin layer of the body is 15 mg / m ² or more and 60 mg / m ² or less. In the battery packaging material of the present invention, the lubricant is present on the surface of the base material layer 1, and the amount of the lubricant present on the surface of the battery packaging material 10 is in such a specific range. It has high moldability and is excellent in battery continuous productivity. The details of this mechanism are not expected to be limited, but are considered as follows. That is, when a lubricant is present on the surface of the base material layer 1 and the total amount of the lubricant is 15 mg / m ² or more, the sliding property between the mold and the battery packaging material is improved, and the male mold is drawn. In this case, since the battery packaging material is easily pulled in, deep drawing can be performed, and it is considered that pinholes and tears are less likely to occur. On the other hand, when the total amount of the lubricant is 60 mg / m ² or less, it is possible to effectively prevent the lubricant from being deposited on the mold used for molding during the continuous production of the battery. It is considered that the re-transfer is difficult to occur and adhesion failure is easily avoided during heat sealing.

As a method of setting the total amount of the lubricant in the range of 15 mg / m ² or more and 60 mg / m ² or less, a method of applying a lubricant to the surface of the base material layer 1 side or the heat-fusible resin layer 4 side, A lubricant is included in the resin constituting the base layer 1 side (for example, the base layer 1 or the surface coating layer 6) or the heat-fusible resin layer 4 and heated to bleed out the lubricant on the surface. The method of letting it be mentioned.

From the viewpoint of a battery packaging material having higher moldability and excellent battery continuous productivity, the amount of lubricant on the base material layer side of the laminate and the heat-fusible resin of the laminate As the total amount of the lubricant on the surface of the layer, the lower limit is preferably 20 mg / m ² or more, more preferably more than 40 mg / m ² , and the upper limit is preferably 50 mg / m ² or less. Moreover, as a preferable range of the total amount of the lubricant, 20 mg / m ² or more and 50 mg / m ² or less, more than 40 mg / m ^{2 and} 50 mg / m ² or less can be mentioned. In addition, as for the kind of lubricant which exists in the surface of a laminated body, what was illustrated in the below-mentioned base material layer 1 is mentioned. In addition, as a method for measuring the amount of lubricant on the surface of the laminate, a predetermined area on the surface of the laminate is washed away with a solvent, and the amount of lubricant contained in the obtained cleaning liquid (solvent) is measured with a gas chromatograph mass spectrometer (GC- MS).

Further, the amount of lubricant present on the surface of the laminate on the substrate layer side is 3 mg / m ² or more and 15 mg / m ² or less, and the amount of lubricant on the substrate layer side of the laminate and the heat of the laminate The total amount of lubricant on the surface of the fusible resin layer is more than 40 mg / m ² , preferably more than 40 mg / m ^{2 and} 50 mg / m ² or less, thereby improving the moldability of battery packaging materials and the continuous productivity of batteries. While improving, the printing characteristic of the surface of the base material layer 1 can be improved.

2. Each layer forming the battery packaging material [base material layer 1]
In the battery packaging material 10 of the present invention, the base material layer 1 is a layer located on the outermost layer side. The material for forming the base material layer 1 is not particularly limited as long as it has insulating properties. Examples of the material for forming the base material layer 1 include polyester, polyamide, epoxy resin, acrylic resin, fluorine resin, polyurethane, silicon resin, phenol resin, polyetherimide, polyimide, polycarbonate, and a mixture or copolymer thereof. Etc. Among these, it is preferable that the base material layer 1 has at least one layer among the layer formed with polyester and the layer formed with polyamide.

  Specific examples of polyesters include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, copolymerized polyester mainly composed of ethylene terephthalate, and butylene terephthalate mainly composed of repeating units. And the like copolyester. The copolymer polyester mainly composed of ethylene terephthalate is a copolymer polyester that polymerizes with ethylene isophthalate mainly composed of ethylene terephthalate (hereinafter, polyethylene (terephthalate / isophthalate)). Abbreviated), polyethylene (terephthalate / isophthalate), polyethylene (terephthalate / adipate), polyethylene (terephthalate / sodium sulfoisophthalate), polyethylene (terephthalate / sodium isophthalate), polyethylene (terephthalate / phenyl-dicarboxylate) And polyethylene (terephthalate / decane dicarboxylate). In addition, as a copolymer polyester mainly composed of butylene terephthalate as a repeating unit, specifically, a copolymer polyester that polymerizes with butylene isophthalate having butylene terephthalate as a repeating unit (hereinafter referred to as polybutylene (terephthalate / isophthalate)). For example, polybutylene (terephthalate / adipate), polybutylene (terephthalate / sebacate), polybutylene (terephthalate / decanedicarboxylate), polybutylene naphthalate, and the like. These polyesters may be used individually by 1 type, and may be used in combination of 2 or more type. Polyester has the advantage of being excellent in electrolytic solution resistance and less likely to cause whitening due to the adhesion of the electrolytic solution, and is suitably used as a material for forming the base material layer 1.

  Specific examples of polyamides include aliphatic polyamides such as nylon 6, nylon 66, nylon 610, nylon 12, nylon 46, and a copolymer of nylon 6 and nylon 66; terephthalic acid and / or isophthalic acid Nylon 6I, Nylon 6T, Nylon 6IT, Nylon 6I6T (I represents isophthalic acid, T represents terephthalic acid) and the like, and polymetaxylylene azide Polyamide containing aromatics such as Pamide (MXD6); Cycloaliphatic polyamides such as Polyaminomethylcyclohexyl Adipamide (PACM6); and Lactam components and isocyanate components such as 4,4′-diphenylmethane-diisocyanate are copolymerized Polyamid , Polyester amide copolymer and polyether ester amide copolymer is a copolymer of a copolyamide and a polyester or a polyalkylene ether glycol; and copolymers thereof. These polyamides may be used individually by 1 type, and may be used in combination of 2 or more type. The stretched polyamide film is excellent in stretchability, can prevent whitening due to resin cracking of the base material layer 1 during molding, and is suitably used as a material for forming the base material layer 1.

  The base material layer 1 may be formed of a uniaxially or biaxially stretched resin film, or may be formed of an unstretched resin film. Among them, a uniaxially or biaxially stretched resin film, in particular, a biaxially stretched resin film has improved heat resistance due to orientation crystallization, and thus is suitably used as the base material layer 1. Moreover, the base material layer 1 may be formed by coating the above-mentioned material on the barrier layer 3.

  Among these, as a resin film which forms the base material layer 1, Preferably nylon and polyester, More preferably, biaxially stretched nylon and biaxially stretched polyester are mentioned.

  The base material layer 1 can be laminated (multi-layer structure) of at least one of resin films and coatings of different materials in order to improve pinhole resistance and insulation when used as a battery packaging. is there. 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 1 has a multilayer structure, a laminate of a biaxially stretched nylon film and a biaxially stretched polyester film, a laminate in which a plurality of biaxially stretched nylon films are laminated, and a laminate in which a plurality of biaxially stretched polyester films are laminated The body is preferred. For example, when the base material layer 1 is formed of two resin films, the polyester resin and the polyester resin are laminated, the polyamide resin and the polyamide resin are laminated, or the polyester resin and the polyamide resin are laminated. 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. In addition, since the biaxially stretched polyester is difficult to discolor when the electrolytic solution adheres to the surface, for example, the base material layer 1 has a multilayer structure of a laminate of a biaxially stretched nylon film and a biaxially stretched polyester film. The base material layer 1 is preferably a laminate having biaxially stretched nylon and biaxially stretched polyester in this order from the barrier layer 3 side. When the base material layer 1 has a multilayer structure, the thickness of each layer is preferably about 2 μm or more and 25 μm or less.

  When making the base material layer 1 into a multilayer structure, each resin film may be adhere | attached through an adhesive agent, and may be laminated | stacked directly without an adhesive agent. In the case of bonding without using an adhesive, for example, a method of bonding in a hot melt state such as a co-extrusion method, a sandwich lamination method, a thermal lamination method, and the like can be given. Moreover, when making it adhere | attach through an adhesive agent, the adhesive agent to be used may be a two-component curable adhesive, or a one-component curable adhesive. Furthermore, the bonding mechanism of the adhesive is not particularly limited, and may be any of a chemical reaction type, a solvent volatilization type, a heat melting type, a hot pressure type, an electron beam curable type, an ultraviolet curable type, and the like. Specific examples of the adhesive include those similar to the adhesive exemplified in the adhesive layer 2. Further, the thickness of the adhesive can be the same as that of the adhesive layer 2.

The amount of the lubricant present on the surface of the base material layer 1 is not particularly limited as long as the total amount is satisfied. However, the battery packaging has a higher formability and excellent battery continuous productivity. From the viewpoint of the material, it is preferably 3 mg / m ² or more, more preferably 4 mg / m ² or more and 15 mg / m ² or less, further preferably 5 mg / m ² or more and 14 mg / m ² or less. By setting the amount of the lubricant present on the surface of the base material layer 1 to such a value, the printing characteristics on the surface of the base material layer 1 can be improved. The method for measuring the amount of lubricant present on the surface of the base material layer 1 is the same as the method for measuring the amount of lubricant present on the surface of the laminate.

  As a method for setting the amount of the lubricant present on the surface of the base material layer 1 to the above-mentioned amount, a method of applying the lubricant to the surface of the base material layer 1 or including a lubricant in the resin constituting the base material layer 1. And a method of bleeding out the lubricant on the surface by heating.

  Although it does not restrict | limit especially as a kind of 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. Examples include 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.

  As a preferable molecular weight of the lubricant, about 100 to 1000 can be mentioned. The molecular weight of the lubricant can be measured by washing the surface of the base material layer with a solvent and analyzing the resulting washing solution by field desorption mass spectrometry.

  The base material layer 1 may have a corona-treated surface. Since the surface of the base material layer 1 is corona-treated, the printing characteristics of the surface of the base material layer 1 can be improved.

  The thickness of the base material layer 1 is preferably about 4 μm or more from the viewpoint of making the battery packaging material 10 excellent in shape stability after molding while reducing the thickness of the battery packaging material 10. Is about 10 μm to 75 μm, more preferably about 10 μm to 50 μm.

In the battery packaging material of the present invention, from the viewpoint of improving moldability, the base material layer 1 uses the total reflection method of Fourier transform infrared spectroscopy for the outermost layer side (opposite side of the barrier layer 3). When the infrared absorption spectrum in 18 directions is obtained in increments of 10 ° from 0 ° to 170 °, the following surface orientation degree satisfying the following formula (surface orientation degree: Y _max / Y _min ): Y _max / It is preferable to include a polyester film with Y _min .
Y _max / Y _min = 1.4 or more and 2.7 or less Y _max is the maximum value obtained by dividing the absorption peak intensity Y ₁₃₄₀ of the infrared absorption spectrum in the 18 directions by the absorption peak intensity Y ₁₄₁₀ .
Y _min is the minimum value obtained by dividing the absorption peak intensity Y ₁₃₄₀ of the infrared absorption spectrum in the 18 directions by the absorption peak intensity Y ₁₄₁₀ .
In the calculation of the maximum value Y _max and the minimum value Y _min , Y ₁₃₄₀ / Y ₁₄₁₀ is obtained for each of the 18 directions, and the maximum value Y _max and the minimum value Y _min are selected from these, respectively.

Specific measurement conditions of the infrared absorption spectrum are as follows. In addition, the measurement of the infrared absorption spectrum in the surface of a polyester film can be performed in the state laminated | stacked on the packaging material for batteries, if the surface of the polyester film was exposed. Moreover, when the below-mentioned surface coating layer 6 etc. are laminated | stacked on the surface of the polyester film, it can measure as the state which removed the said surface coating layer 6 and the surface of the polyester film exposed. For example, when a base material layer acquires a polyester film from a battery packaging material including a polyester film and a polyamide film in order from the barrier layer side, and performs measurement using the total reflection method of Fourier transform spectroscopy The polyamide film is peeled or dissolved from the polyester film, and the absorption peak intensity Y ₁₃₄₀ and the absorption peak intensity Y ₁₄₁₀ can be measured for the obtained polyester film.

(Infrared absorption spectrum measurement conditions)
Spectrometer (attached with a one-time reflection ATR accessory)
Detector: MCT (Hg Cd Te)
Wave number resolution: 8cm-1
IRE: Ge
Incident angle: 30 °
Polarizer: Wire grid, S polarized light Base line: Average value of intensity in the range of wave numbers 1800 cm −1 to 2000 cm −1 Absorption peak intensity Y ₁₃₄₀ : Base from maximum peak intensity in the range of wave numbers 1335 cm −1 to 1342 cm −1 Absorption peak intensity Y ₁₄₁₀ minus line value minus peak value in the range of wave numbers from 1400 cm -1 to ₁₄₁₀ cm -1

  The infrared absorption spectrum in 18 directions is obtained by placing a polyester film as a sample horizontally on a sample holder and rotating the Ge crystal placed on the sample by 10 °. The incident angle is an angle between a normal line (normal line) and incident light.

From the viewpoint of further improving the moldability of the battery packaging material, the degree of surface orientation (Y _max / Y _min ) is more preferably 1.6 or more and 2.7 or less, and further preferably 1.6 or more and 2.4. The following are mentioned.

The polyester film having the above surface orientation degree: Y _max / Y _min is obtained by appropriately adjusting, for example, a stretching method, a stretching ratio, a stretching speed, a cooling temperature, a heat setting temperature, etc. in manufacturing the polyester film. Can be manufactured. Moreover, as a polyester film, a commercial item can be used.

  The polyester film is preferably composed of a biaxially stretched polyester film, particularly a biaxially stretched polyethylene terephthalate film.

  The thickness of the polyester film is not particularly limited, but is preferably about 20 μm or less, more preferably about 1 μm or more and about 15 μm or less, more preferably from the viewpoint of exhibiting excellent moldability while thinning the battery packaging material. Examples include about 3 μm to 12 μm.

[Adhesive layer 2]
In the battery packaging material 10 of the present invention, the adhesive layer 2 is a layer provided between the base material layer 1 and the barrier layer 3 as necessary in order to firmly bond the base material layer 1 and the barrier layer 3.

  The adhesive layer 2 is formed of an adhesive capable of bonding the base material layer 1 and the barrier layer 3 together. The adhesive used for forming the adhesive layer 2 may be a two-component curable adhesive or a one-component curable adhesive. Furthermore, the bonding mechanism of the adhesive used for forming the adhesive layer 2 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 2 include polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, and copolyester; polycarbonate; 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, cellulose adhesives, (meth) acrylic resins, polyimide resins, urea resins, melamine resins and other amino resins, chloroprene rubber, nitrile rubber , Styrene - rubber 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 2 is not particularly limited as long as it exhibits the function as an adhesive layer. For example, the thickness is about 1 μm to 10 μm, preferably about 2 μm to 5 μm.

[Barrier layer 3]
In the battery packaging material 10, 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, more preferably formed of a soft aluminum alloy foil.

  From the viewpoint of improving the formability of the barrier layer 3, the average crystal grain size of the barrier layer 3 (especially when formed of an aluminum alloy foil) is preferably about 10.0 μm or less, and is 1.0 μm or more and 7 It is preferably about 0.0 μm or less, and more preferably about 1.0 μm or more and 3.0 μm or less.

  In the present invention, the average crystal grain size in the aluminum alloy foil layer is obtained by observing a cross section in the thickness direction of the aluminum alloy foil layer with a scanning electron microscope (SEM), and crystal grains 31 of 100 aluminum alloys positioned in the field of view. As shown in the schematic diagram of FIG. 5, it means a value obtained by measuring the maximum diameter x of each crystal grain and averaging the maximum diameter x of 100 crystal grains. As shown in the schematic diagram of FIG. 5, the maximum diameter x of each crystal grain is a straight line connecting one point of the crystal grain extension and the other point of the same crystal grain extension for the crystal grain observed by the SEM. It means the diameter where the distance is the maximum. The cross section in the thickness direction of the aluminum alloy foil layer observed by SEM is a cut surface obtained by cutting the cross section along a plane perpendicular to the rolling direction. Since FIG. 5 is a schematic diagram, drawing is omitted and 100 crystal grains 31 are not drawn.

  Further, in the present invention, in each of the 100 second phase particles 32 in the field of view in which the barrier layer 3 is observed with an optical microscope, in the cross section in the thickness direction of the laminate constituting the battery packaging material, When the diameter y of the phase particles is measured, the average of the diameters y of the top 20 second phase particles in order of increasing diameter y is preferably about 5.0 μm or less, and 1.0 μm or more and 4. More preferably, it is about 0 μm or less, and further preferably about 1.0 μm or more and 3.5 μm or less. As shown in the schematic diagram of FIG. 5, the diameter y of each second phase particle is the same as the other point of the extension of the same second phase particle and the one point of the extension of the second phase particle. It means the diameter where the linear distance connecting The average crystal grain size in the barrier layer 3 is about 10.0 μm or less and the diameter of the second phase particles 32 is in such a range, thereby further improving the moldability of the battery packaging material. Can do. Since FIG. 5 is a schematic diagram, drawing is omitted and 100 second phase particles 32 are not drawn.

  In the present invention, for example, when the barrier layer 3 is formed of an aluminum alloy, the second phase particles contained in the aluminum alloy form an intermetallic compound such as Al— (Fe · Mn) —Si. Such second phase particles generated during solidification in the casting process are not fixed in the subsequent process and remain.

  When a cross section in the thickness direction of the barrier layer 3 is observed with a scanning electron microscope (SEM), the crystal grains usually draw boundary lines in contact with a plurality of crystals. On the other hand, the second phase particles usually have a single crystal at the boundary line. Further, since the crystal grains and the second phase particles are different in phase, the color is different on the SEM image, and the second phase particles often appear white. Furthermore, when the cross section in the thickness direction of the barrier layer 3 is observed with an optical microscope, observation is easy because only the second phase particles appear black due to the phase difference between the crystal grains and the second phase particles. become.

  When the barrier layer 3 is formed of an aluminum alloy, the composition of the aluminum alloy is 0.7 mass% to 2.5 mass% Fe, 0.05 mass% or less Cu, 0.30 mass% or less. It is preferable to contain Si.

  The thickness of the barrier layer 3 is not particularly limited as long as it functions as a barrier layer such as water vapor. For example, the thickness is about 10 μm to 100 μm, preferably about 10 μm to 55 μm, more preferably about 10 μm to 38 μm. Can be about.

  The barrier layer 3 is preferably provided with an undercoat layer on at least one surface, preferably both surfaces, for the purpose of stabilizing adhesion, preventing dissolution and corrosion, and the like. Here, the undercoat layer is a layer formed by subjecting the surface of the barrier layer to a chemical conversion treatment, and the chemical conversion treatment refers to a treatment for forming an acid-resistant coating 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 chromate treatment using phosphoric acid compounds 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) Examples thereof include chromate treatment. In the aminated phenol polymer, the repeating units represented by the following general formulas (1) to (4) may be included singly or in any combination of two or more. Also good.

In general formulas (1) to (4), X represents a hydrogen atom, a hydroxyl 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 hydroxyl 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 a linear or branched alkyl group 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- A 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 hydroxyl group or a hydroxyalkyl group. The number average molecular weight of the aminated phenol polymer having the repeating units represented by the general formulas (1) to (4) is preferably, for example, from 500 to 1,000,000, and preferably from 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 a corrosion-resistant undercoat film layer 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 corrosion-resistant undercoat film layer. 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.

  As the chemical conversion treatment, only one type of chemical conversion treatment may be performed, or two or more types of chemical conversion treatment 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 treatment, a chemical conversion treatment combining a chromium compound, a phosphate compound, and an aminated phenol polymer are preferable. Of the chromium compounds, chromic acid compounds are preferred.

The amount of the undercoat layer formed on the surface of the barrier layer 3 in the chemical conversion treatment is not particularly limited. For example, in the case of performing the above chromate treatment, a chromic acid compound is present per 1 m ² of the surface of the barrier layer 3. About 0.5 mg to 50 mg or less in terms of chromium, preferably about 1.0 mg to about 40 mg or less, Phosphorus compound in terms of phosphorus being about 0.5 mg to about 50 mg, preferably about 1.0 mg to about 40 mg, and aminated phenol weight It is desirable that the coalescence is contained in a ratio of about 1 mg to 200 mg, preferably about 5.0 mg to 150 mg.

  In the chemical conversion treatment, a solution containing a compound used for forming the undercoat layer is applied to the surface of the barrier layer by a bar coating method, a roll coating method, a gravure coating method, an immersion method, or the like, and then the temperature of the barrier layer is 70. It is performed by heating so that the temperature is about 200 ° C. or higher. 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 in the heat-fusible resin layer 4 is not particularly limited as long as it can be heat-sealed, and examples thereof include polyolefins, cyclic polyolefins, carboxylic acid-modified polyolefins, and carboxylic acid-modified cyclic polyolefins. It is done.

  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 Polypropylene, such as a random copolymer of (for example, a random copolymer of propylene and ethylene); a terpolymer of ethylene-butene-propylene, 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. Moreover, styrene is also mentioned as a monomer.

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

  The carboxylic 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 α, β with respect to the cyclic polyolefin. -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 that used for modification of the polyolefin.

  Among these resin components, carboxylic acid-modified polyolefin is preferable; carboxylic acid-modified polypropylene is more preferable.

  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.

Further, it is preferable that a lubricant is present on the surface of the heat-fusible resin layer 4. The amount of lubricant present on the surface of the heat-fusible resin layer 4 is not particularly limited as long as it satisfies the above total amount, but has higher moldability and excellent battery continuous productivity. from the viewpoint of the battery packaging material, preferably 10 mg / m ² or more, 50 mg / m ² degree or less, more preferably 15 mg / m ² or more, and the degree 40 mg / m ² or less. The method for measuring the amount of lubricant present on the surface of the heat-fusible resin layer 4 is the same as the method for measuring the amount of lubricant present on the surface of the laminate. In addition, as for the kind of lubricant which exists in the surface of the heat-fusible resin layer 4, what was illustrated in the above-mentioned base material layer 1 is mentioned.

  As a method of setting the amount of the lubricant present on the surface of the heat-fusible resin layer 4 to the above amount, a method of applying a lubricant to the surface of the heat-fusible resin layer 4, A method of causing the lubricant to bleed out on the surface by adding a lubricant to the resin to be constituted and heating the resin is mentioned.

  Further, the thickness of the heat-fusible resin layer 4 is not particularly limited as long as it exhibits the function as the heat-fusible resin layer, but is preferably about 60 μm or less, more preferably about 15 μm or more and 40 μm or less.

[Adhesive layer 5]
In the battery packaging material of the present invention, the adhesive layer 5 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 5 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 5, the same adhesive mechanism and the same types of adhesive components as those exemplified for the adhesive layer 2 can be used. Further, as the resin used for forming the adhesive layer 5, 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.

  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 5 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 nurate, 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 5, 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 5 is preferably in the range of 0.1% by mass or more and 50% by mass or less, and in the range of 0.1% by mass or more and 30% by mass or less. More preferably, it is more preferably in the range of 0.1% by mass or more and 10% by mass or less.

  The thickness of the adhesive layer 5 is not particularly limited as long as it functions as an adhesive layer. However, when the adhesive exemplified in the adhesive layer 2 is used, it is preferably about 2 μm or more and 10 μm or less, more preferably For example, about 2 μm or more and 5 μm or less. Moreover, when using the resin illustrated by the heat-fusible resin layer 4, Preferably they are 2 micrometers or more and about 50 micrometers or less, More preferably, they are about 10 micrometers or more and 40 micrometers or less. 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 μm or more and about 20 μm or less, and further preferably about 0.5 μm or more and about 5 μm or less. It is done. In the case where the adhesive layer 5 is a cured product of a resin composition containing an acid-modified polyolefin and a curing agent, the adhesive layer 5 can be formed by applying the resin composition and curing it by heating or the like.

[Surface coating layer 6]
In the battery packaging material 10 of the present invention, for the purpose of improving design properties, electrolytic solution resistance, scratch resistance, moldability, and the like, the base material layer 1 (barrier of the base material layer 1) may be used as necessary. If necessary, a surface coating layer 6 may be provided on the side opposite to the layer 3. The surface coating layer 6 is a layer located in the outermost layer when the battery is assembled. When the surface coating layer 6 is provided, the lubricant is present on the surface of the surface coating layer 6 of the battery packaging material (that is, the surface on the base material layer 1 side).

  The surface coating layer 6 can be formed of, for example, polyvinylidene chloride, polyester resin, urethane resin, acrylic resin, epoxy resin, or the like. Moreover, you may form the surface coating layer 6 with the mixed resin which combined the urethane resin, the acrylic resin, etc. from a viewpoint which further improves the electrolyte solution resistance of the surface of the packaging material for batteries. 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 preferable from the viewpoints 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 method for forming the surface coating layer 6 is not particularly limited, and examples thereof include a method of applying a two-component curable resin for forming the surface coating layer 6 on one surface of the base material layer 1. When blending the additive, the additive may be added to the two-component curable resin, mixed, and then applied.

  Although it does not restrict | limit especially as content of the additive in the surface coating layer 6, Preferably it is about 0.05 mass% or more and 1.0 mass% or less, More preferably, it is 0.1 mass% or more and 0.5 mass% or less. Degree.

  The thickness of the surface coating layer 6 is not particularly limited as long as the packaging material for the battery satisfies the above physical properties while exhibiting the above function as the surface coating layer 6, for example, about 0.5 μm to 10 μm, preferably Is about 1 μm or more and 5 μm or less.

3. Production method of battery packaging material The production method of the battery packaging material of the present invention is not particularly limited as long as a laminate in which layers of a predetermined composition are laminated is obtained. At least the base material layer 1 and the barrier layer 3 and the heat-fusible resin layer 4 are laminated so as to be in this order to obtain a laminated body. As a method for causing a lubricant to be present on the surface of the base material layer 1 side, the lubricant may be applied to the surface of the base material layer 1 side, or a layer on the base material layer 1 side (for example, the base material layer 1 or the surface coating layer). A lubricant may be included in the resin constituting 6), and the lubricant may be bleed out on the surface of the base layer 1 side. Similarly, a lubricant may be applied to the surface of the heat-fusible resin layer 4, or a lubricant may be included in the resin constituting the heat-fusible resin layer 4 so that the surface of the heat-fusible resin layer 4 is covered. The lubricant may be bleed out.

  An example of the method for producing the battery packaging material of the present invention is as follows. First, a laminate in which the base material layer 1, the adhesive layer 2, and the barrier layer 3 are laminated in this order (hereinafter also referred to as “laminate A”) is formed. Specifically, the laminate A is formed by applying an adhesive used for forming the adhesive layer 2 on the base layer 1 or the barrier layer 3 whose surface is subjected to a chemical conversion treatment, if necessary, a gravure coating method, After applying and drying by a coating method such as a roll coating method, the barrier layer 3 or the base material layer 1 can be laminated and the adhesive layer 2 can be cured by a dry laminating method.

  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. What is necessary is just to apply | coat by methods, such as. When the adhesive layer 5 is provided between the barrier layer 3 and the heat-fusible resin layer 4, for example, (1) the adhesive layer 5 and the heat-fusible resin layer on the barrier layer 3 of the laminate A 4 by coextrusion (coextrusion lamination method), (2) Separately, a laminate in which the adhesive layer 5 and the heat-fusible resin layer 4 are laminated is formed, and this is formed as a barrier layer of the laminate A 3 by a thermal laminating method, and (3) an extrusion method for forming an adhesive layer 5 on the barrier layer 3 of the laminate A or a method of drying or baking at a high temperature after solution coating. A method of laminating and laminating the heat-fusible resin layer 4 previously formed into a sheet shape on the adhesive layer 5 by a thermal laminating method, (4) the barrier layer 3 of the laminate A, and forming a sheet in advance Between the heat-sealable resin layer 4 and the melted adhesive While pouring 5, and a method of bonding a laminate A and the heat-welding resin layer 4 through the adhesive layer 5 (sandwich lamination method).

  When the surface coating layer 6 is provided, the surface coating layer 6 is laminated on the surface of the base material layer 1 opposite to the barrier layer 3. The surface coating layer 6 can be formed, for example, by applying the above-described resin for forming the surface coating layer 6 to the surface of the base material layer 1. The order of the step of laminating the barrier layer 3 on the surface of the base material layer 1 and the step of laminating the surface coating layer 6 on the surface of the base material layer 1 are not particularly limited. For example, after forming the surface coating layer 6 on the surface of the base material layer 1, the barrier layer 3 may be formed on the surface of the base material layer 1 opposite to the surface coating layer 6.

  Surface coating layer 6 provided as necessary / base material layer 1 / adhesive layer 2 provided as necessary / barrier layer 3 whose surface is subjected to chemical conversion treatment as necessary / as required In order to strengthen the adhesiveness of the adhesive layer 2 and the adhesive layer 5 provided as necessary, a laminate comprising the adhesive layer 5 / the heat-fusible resin layer 4 provided is formed. You may use for heat processing, such as a hot roll contact type, a hot-air type, a near or far-infrared type. Examples of such heat treatment conditions include 150 to 250 ° C. and 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. Furthermore, for example, by applying a corona treatment to the surface of the base material layer 1 opposite to the barrier layer 3, the printability of the ink on the surface of the base material layer 1 can be improved.

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 used in the battery packaging material of the present invention, with the metal terminal 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 in the package formed of the battery packaging material of the present invention, the heat-fusible resin layer portion of the battery packaging material of the present invention is the inner side (surface in contact with the battery element). Thus, a package is formed.

  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 battery, a nickel / hydrogen battery, a nickel / cadmium battery Nickel / iron livestock batteries, nickel / zinc livestock batteries, silver oxide / zinc livestock 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.

(Example 1-29 and Comparative Example 1-14)
<Manufacture of battery packaging materials>
On the base material layer formed of the resin of Table 1, an aluminum alloy foil (thickness 35 μm) as a barrier layer was laminated by a dry laminating method. Specifically, a two-component urethane adhesive (a polyol compound and an aromatic isocyanate compound) was applied to one surface of the aluminum alloy foil, and an adhesive layer (thickness 3 μm) was formed on the aluminum alloy foil. Next, after laminating the adhesive layer and the base material layer on the barrier layer by the dry laminating method, an aging treatment is carried out at 40 ° C. for 24 hours to obtain a base material layer / adhesive layer / barrier layer laminate. Produced. In addition, the chemical conversion treatment was performed on both surfaces of the aluminum alloy foil. The chemical conversion treatment of the aluminum alloy foil is performed on both sides of the aluminum foil by a roll coating method so that the treatment amount of the phenol resin, the chromium fluoride compound, and phosphoric acid is 10 mg / m ² (dry mass). The film was baked for 20 seconds under the condition that the film temperature was 180 ° C. or higher. Next, 20 μm of carboxylic acid-modified polypropylene (arranged on the barrier layer side) and 15 μm of random polypropylene (innermost layer side) are coextruded on the barrier layer of the laminate, thereby heat-bonding the adhesive layer and the adhesive layer onto the barrier layer. A resin layer was laminated to obtain a battery packaging material in which a base material layer / adhesive layer / barrier layer / adhesive layer / heat-sealable resin layer were laminated in this order.

  In Examples 1-7 and 9-29, the lubricant present on the surface of the battery packaging material is prepared by blending a lubricant (erucic acid amide) in the resin constituting the base material layer and the heat-fusible resin layer. After the battery packaging material is manufactured, it is heated for a certain time and bleeded out. On the other hand, the lubricant of Example 8 is obtained by applying a lubricant (erucic amide) to the surface of the base material layer and the heat-fusible resin layer after producing the battery packaging material.

  As the aluminum alloy foil, in Examples 1-21, 23-28 and Comparative Example 1-14, the above-mentioned average crystal grain size is 10 μm or less, and the above-mentioned second phase particle diameter is 3 μm or less. In Example 22, the above-mentioned average crystal grain size was more than 10 μm and the above-mentioned second phase particles had a diameter of 3 μm or less. Also. In Example 29, the above-mentioned average crystal grain size is 10 μm or less and the above-mentioned second phase particle diameter is 6 μm.

  The average crystal grain size and the second phase particles of the aluminum alloy foil were measured by the following methods, respectively.

<Measurement of average grain size of aluminum alloy foil>
The average crystal grain size in the aluminum alloy foil used as the aluminum alloy foil layer in Examples and Comparative Examples is a scanning electron microscope (product name S-4800 manufactured by Hitachi High-Technologies Corporation) in the thickness direction of the aluminum alloy foil layer. The crystal grains of 100 aluminum alloys positioned in the field of view are randomly selected, the maximum diameter x of each crystal grain is measured, and the maximum diameter x of the 100 crystal grains is averaged. It was. The maximum diameter x of each crystal grain means a diameter at which a linear distance connecting one point of the outer extension of the crystal grain and the other point of the outer extension of the same crystal grain becomes the maximum for the crystal grain observed by SEM.

<Measurement of second phase particle diameter of aluminum alloy foil>
The second phase particle diameter of the aluminum alloy foil used as the aluminum alloy foil layer of Examples and Comparative Examples was observed with an optical microscope (product name CX31-P manufactured by OLYMPUS) in the cross section in the thickness direction. 100 second-phase particles were randomly selected and obtained as an average value of the diameters y of the individual second-phase particles. The diameter y of each second phase particle is the diameter at which the linear distance connecting one point of the extension of the second phase particle and the other point of the extension of the same second phase particle is the maximum for the particle observed by SEM. means.

(Measurement of lubricant amount)
Each battery packaging material obtained above was cut into A4 size to produce samples. Next, the base material layer side surface and the heat-fusible resin layer surface of each sample were each washed with 30 ml of methanol, and the recovered methanol was volatilized and dried by nitrogen blowing to obtain a solid. Next, 1.5 ml of methanol was added to the solid matter to redissolve the solid matter, and a gas chromatograph mass spectrometer (GCMS, QP2010 manufactured by Shimadzu Corporation, ionization method: electron impact ionization method (EI method), detector: Using a quadrupole detector, column: Inert Cap 5MS, the amount of lubricant on the substrate layer side surface and the heat-fusible resin layer surface was measured. As a result, the surface lubricant amount in each battery packaging material was a value shown in Table 1.

<Measurement of surface orientation>
The total reflection method of Fourier transform infrared spectroscopy (FT-IR) for the polyethylene terephthalate (PET) film surface (surface opposite to the barrier layer) used for the base material layer in Examples 11-15 and 23-28 (ATR) is used to obtain an infrared absorption spectrum in 18 directions in increments of 10 ° from 0 ° to 170 °, and an absorption peak intensity Y ₁₃₄₀ (CH ₂ longitudinal vibration) of the infrared absorption spectrum in 18 directions, Y ₁₃₄₀ / Y ₁₄₁₀ is calculated from the value of the absorption peak intensity Y ₁₄₁₀ (C = C stretching vibration), and the degree of surface orientation: Y _max / Y _min is calculated from the maximum value Y _max and the minimum value Y _min among them. Calculated.

The results are shown in Table 1. In Examples 11-16, Y _max was 2.1, Y _min was 1.3, and the degree of surface orientation: Y _max / Y _min was 1.60. In Example 23, Y _max was 2.21, Y _min was 1.13, and the degree of surface orientation: Y _max / Y _min was 1.96. In Example 24, Y _max was 2.14, Y _min was 1.08, and the degree of surface orientation: Y _max / Y _min was 1.98. In Example 25, Y _max was 2.16, Y _min was 1.18, and the degree of surface orientation: Y _max / Y _min was 1.83. In Example 26, Y _max was 1.99, Y _min was 1.28, and the degree of surface orientation: Y _max / Y _min was 1.55. In Example 27, Y _max was 2.15, Y _min was 1.14, and the degree of surface orientation: Y _max / Y _min was 1.89. In Example 28, Y _max was 2.22, Y _min was 1.06, and the degree of surface orientation: Y _max / Y _min was 2.09.

(Infrared absorption spectrum measurement conditions)
Spectrometer: Nicolet iS10 FT-IR manufactured by Thermo Fisher Scientific
Attached device: One-time reflection ATR accessory device (Seagull)
Detector: MCT (Hg Cd Te)
Wave number resolution: 8cm-1
IRE: Ge
Incident angle: 30 °
Polarizer: Wire grid, S polarized light Base line: Average value of intensity in the range of wave numbers 1800 cm −1 to 2000 cm −1 Absorption peak intensity Y ₁₃₄₀ : Base from maximum peak intensity in the range of wave numbers 1335 cm −1 to 1342 cm −1 Value obtained by subtracting the line value Absorption peak intensity Y ₁₄₁₀ : A value obtained by subtracting the baseline value from the maximum value of the peak intensity in the range of wave numbers from 1400 cm −1 to ₁₄₁₀ cm −1.

  Infrared absorption spectra in 18 directions were obtained by placing a polyester film as a sample horizontally on a sample holder and rotating the Ge crystal placed on the sample by 10 °. The incident angle is an angle between a normal line (normal line) and incident light.

(Formability evaluation)
Each battery packaging material obtained above was cut into a 80 mm × 120 mm rectangle to prepare a sample. In an environment of a temperature of 24 ° C. and a relative humidity of 50%, these samples were molded into a mold having a diameter of 30 mm × 50 mm (female mold, surface is JIS B 0659-1: 2002 Annex 1 (reference) Comparative surface The maximum height roughness (nominal value of Rz) specified in Table 2 of the roughness standard piece is 3.2 μm, and a molding die corresponding to this (male mold, surface is JIS B 0659-1) : Appendix 1 of the 2002 (reference) The maximum height roughness (nominal value of Rz is 1.6 μm) defined in Table 2 of the comparative surface roughness standard piece is used, and the presser pressure is 0.4 MPa. The molding depth is increased from the molding depth of 0.5 mm in increments of 0.5 mm, and the molding depth is 0.5 mm shallower than the molding depth when the pinhole is generated in the battery packaging material. The limit forming depth of the sample was used. From this limit molding depth, the moldability of the battery packaging material was evaluated according to the following criteria. The results are shown in Table 1.
A: Limit forming depth 6.0 mm or more B: Limit forming depth 5.0 mm or more and 5.5 mm or less C: Limit forming depth 4.0 mm or more and 4.5 mm or less D: Limit forming depth 3.5 mm or less

(Evaluation of continuous productivity of batteries)
Each battery packaging material obtained above was cut into a 80 mm × 120 mm rectangle to prepare a sample. Next, in an environment of a temperature of 24 ° C. and a relative humidity of 50%, these samples were molded into a mold having a diameter of 30 mm × 50 mm (female mold, the surface is JIS B 0659-1: 2002, Annex 1 (reference) The maximum height roughness (nominal value of Rz) defined in Table 2 of the comparative surface roughness standard piece is 3.2 μm) and the corresponding molding die (male mold, surface is JIS B 0659-1: 2002 Annex 1 (Reference) The presser pressure is 0 using the maximum height roughness (nominal value of Rz is 1.6 μm) defined in Table 2 of the comparative surface roughness standard piece. 1000 pieces each were cold formed at a forming depth of 5 mm at 4 MPa. Next, the corner part of the metal mold | die after performing cold forming was observed visually, and the continuous moldability of the battery packaging material was evaluated from the following references | standards.
A: The lubricant has not been transferred to the male mold and the female mold, and the mold is not whitened, so the continuous formability is high. B: The lubricant has transferred to only one of the male mold and the female mold, Continuous moldability is slightly high because the mold is slightly whitened. C: The lubricant is transferred to both the male mold and the female mold, and the mold is whitened, so the continuous moldability is low.

(Evaluation of printability)
A pattern was printed by pad printing on the surface of the base material layer of each battery packaging material obtained above. The pad printer used was SPACE PAD 6GX manufactured by Mishima Co., Ltd., and the ink used was UV ink PJU-A black manufactured by Navitas Co., Ltd. Further, UV was irradiated for 30 seconds from a distance of 10 cm at an ultraviolet wavelength of 254 nm with an As One handy UV lamp SUV-4 to cure the ink. The printed surface after curing was observed with an optical microscope and evaluated according to the following criteria. The results are shown in Table 1. The printability evaluation was performed in an environment at 24 ° C. and a relative humidity of 50%.
5: There is no missing print in the visible range. 4: The missing print is 2.5% or less of the entire printed pattern. 3: The missing print is more than 2.5% of the entire printed pattern and 5% or less. 2: There is more than 5% of the printed pattern and less than 10% of the entire printed pattern 1: There is more than 10% of the printed pattern that is missing

(Evaluation of tape peelability)
A pattern was printed by pad printing on the surface of the base material layer of each battery packaging material obtained above in the same manner as the evaluation of the printability described above. A scotch tape # 600 manufactured by 3M was attached to the printed surface after curing by reciprocating once with a 200 g rubber roller. Next, the attached tape was peeled off at a peeling angle of 90 °. The surface of the base material layer (printed surface) where the tape was peeled off was observed with an optical microscope, and evaluated according to the following criteria within a range that could be visually confirmed. The results are shown in Table 1. Note that the tape peelability was evaluated in an environment at 24 ° C. and a relative humidity of 50%.
5: No printing peeling 4: Printing peeling is more than 0% and 25% or less of the entire printed pattern 3: Printing peeling is more than 25% and 50% or less of the whole printing pattern 2: Printing peeling There is more than 50% of the whole printed pattern and 75% or less 1: There is more peeling of printing than 75% of the whole printed pattern

  In Table 1, in Examples 6 and 11 and Comparative Examples 5 and 11, the surface of the base material layer was subjected to corona treatment (marked * in Table 1). In Examples 7 and 14 and Comparative Examples 6 and 12, the surface of the base material layer was subjected to an easy adhesion treatment (marked ** in Table 1). The easy adhesion treatment was formed using a coating solution to which an acrylic resin and an isocyanate crosslinking agent were added. ONy is biaxially stretched nylon, PET is biaxially stretched polyethylene terephthalate, PET / ONy is PET on the opposite side of the barrier layer, and is laminated by dry lamination of polyethylene terephthalate (12μm) and nylon (15μm) It is a film. PET / ONy is a substrate layer formed of a laminated film (HEPTAX HBN (general grade) manufactured by Gunze Co., Ltd.) by coextrusion of polyethylene terephthalate (3 μm) and nylon (12 μm). PP means biaxially stretched polypropylene, PE means biaxially stretched polyethylene, and CPP means unstretched polypropylene.

As is apparent from the results shown in Table 1, a lubricant is present on the surface of the base material layer side, and the amount of lubricant present on the surface of the base material layer side of the laminate and the thermal fusion of the laminate In the battery packaging materials of Examples 1 to 29 in which the total amount of lubricant present on the surface of the conductive resin layer is 15 mg / m ² or more and 60 mg / m ² or less, the battery packaging material has high moldability and the battery It can be seen that the continuous productivity is excellent.

DESCRIPTION OF SYMBOLS 1 Base material layer 2 Adhesive layer 3 Barrier layer 4 Heat-fusion resin layer 5 Adhesive layer 6 Surface coating layer 10 Battery packaging material

Claims (12)

It is composed of a laminate having at least a base material layer, a barrier layer, and a heat-fusible resin layer in this order,
At least on the surface of the laminate on the side of the base material layer, a lubricant is present,
The total of the amount of lubricant on the surface of the laminate on the substrate layer side and the amount of lubricant on the surface of the heat-fusible resin layer of the laminate is 15 mg / m ² or more and 60 mg / m ² or less. Packaging materials. The lubricant amount existing on the surface of the base layer side of the laminate, 3 mg / m ² or more and 15 mg / m ² or less, the packaging material for a battery according to claim 1. The battery packaging material according to claim 1 or 2, wherein the amount of lubricant present on the surface of the heat-fusible resin layer of the laminate is 10 mg / m ² or more and 50 mg / m ² or less.   The battery packaging material according to any one of claims 1 to 3, wherein the base material layer has at least one of a layer formed of polyester and a layer formed of polyamide.   The battery packaging material according to any one of claims 1 to 4, further comprising a surface coating layer on a side opposite to the barrier layer of the base material layer.   The battery packaging material according to claim 1, wherein the lubricant contains an amide-based lubricant.   The battery packaging material according to claim 1, wherein the heat-fusible resin layer includes a layer formed of polyolefin.   The battery packaging material according to any one of claims 1 to 7, further comprising an undercoat layer on at least one surface of the barrier layer.   The battery packaging material according to any one of claims 1 to 8, which is a packaging material for a secondary battery.   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 claim 1. It includes a step of laminating at least a base material layer, a barrier layer, and a heat-fusible resin layer in this order,
At least a lubricant is present on the surface of the laminate on the substrate layer side, and the amount of lubricant on the surface of the laminate on the substrate layer side and the surface of the heat-fusible resin layer of the laminate are A method for producing a battery packaging material, wherein the total amount of lubricant is 15 mg / m ² or more and 60 mg / m ² or less.   The manufacturing method of the packaging material for batteries of Claim 11 further equipped with the process of giving a corona treatment to the surface of at least one of the said base material layer.