Exterior material for power storage device, method for manufacturing same, and power storage device

Abstract

This exterior material for a power storage device is configured from a laminate comprising, in order from the outer side, at least a surface coating layer, a base material layer, a barrier layer, and a heat-fusible resin layer, and at least one layer further to the outer side than the barrier layer contains a coloring agent.

Description

Exterior material for power storage device, manufacturing method thereof, and power storage device

[0001] The present disclosure relates to an exterior material for an electricity storage device, a method for producing the same, and an electricity storage device.

[0002] Various types of electricity storage devices have been developed, and in all of them, exterior materials are essential components for sealing the electricity storage device elements such as electrodes and electrolytes. Conventionally, metal exterior materials have been widely used as exterior materials for electricity storage devices.

[0003] Meanwhile, in recent years, with the increasing performance of electric vehicles, hybrid electric vehicles, personal computers, cameras, mobile phones, etc., there has been a demand for electricity storage devices to have a variety of shapes as well as to be thinner and lighter in weight. However, the metallic exterior materials for electricity storage devices that have been widely used in the past have the drawbacks of being difficult to keep up with the diversification of shapes and also having limitations on how much they can be made lighter.

[0004] Therefore, in recent years, a film-like laminate in which a base layer, a barrier layer, and a heat-sealable resin layer are laminated in this order has been proposed as an exterior material for an electricity storage device that can be easily processed into a variety of shapes and can be made thinner and lighter (see, for example, Patent Document 1).

[0005] In such an electrical storage device packaging material, a recess is generally formed by cold forming, and electrical storage device elements such as electrodes and electrolyte are placed in the space formed by the recess, and a heat-sealable resin layer is heat-sealed to obtain an electrical storage device in which the electrical storage device elements are housed inside the electrical storage device packaging material.

[0006] Japanese Patent Application Laid-Open No. 2008-287971

[0007] As described above, electricity storage devices are used in a variety of products, and in recent years, greater importance has been placed on the design of products to which electricity storage devices are attached.

[0008] The inventors of the present disclosure considered that, for example, by unifying the color of an electricity storage device to be attached to a product with the color of the housing of the product, the color of the electricity storage device and the product to which it is attached can be unified, thereby achieving an excellent design. In conventional exterior materials for electricity storage devices, the appearance of the exterior material for an electricity storage device is not adjusted in advance in consideration of the various colors of the housing of the product to which the electricity storage device is attached, and if such adjustment were possible, it would be possible to further improve the design of the product to which the electricity storage device is attached.

[0009] Under these circumstances, the main object of the present disclosure is to provide an exterior material for an electricity storage device that can color the appearance of the electricity storage device, taking into account the various colors of the housing of the product to which the electricity storage device is attached.

[0010] The inventors of the present disclosure conducted extensive research to solve the above-described problems, and as a result, found that by incorporating a colorant into at least one layer outside the barrier layer in an exterior packaging material for an electricity storage device that is composed of a laminate including, in order from the outside, at least a surface coating layer, a base material layer, a barrier layer, and a heat-sealable resin layer, the exterior packaging material can be colored in consideration of various colors of the housing of a product to which the electricity storage device is attached.

[0011] The present disclosure has been completed based on these findings and through further investigations. That is, the present disclosure provides the following aspects of the invention: An exterior material for an electricity storage device, which is composed of a laminate including, in order from the outside, at least a surface coating layer, a base material layer, a barrier layer, and a heat-sealable resin layer, and at least one layer outside the barrier layer contains a colorant.

[0012] According to the present disclosure, it is possible to provide a packaging material for an electricity storage device that can color the appearance of the electricity storage device in consideration of the color of the housing of a product to which the electricity storage device is attached. The present disclosure also makes it possible to provide a method for manufacturing the packaging material for an electricity storage device, and an electricity storage device that uses the packaging material for an electricity storage device.

[0013] Fig. 1 is a schematic diagram showing an example of the cross-sectional structure of an exterior material for an electricity storage device according to the present disclosure. Fig. 2 is a schematic diagram showing an example of the cross-sectional structure of an exterior material for an electricity storage device according to the present disclosure. Fig. 3 is a schematic diagram for explaining a method of housing an electricity storage device element in a package formed from an exterior material for an electricity storage device according to the present disclosure.

[0014] The packaging material for an electricity storage device according to the present disclosure is composed of a laminate including, in order from the outside, at least a surface coating layer, a base material layer, a barrier layer, and a heat-sealable resin layer, and is characterized in that a colorant is contained in at least one layer outside the barrier layer. By virtue of having this configuration, the packaging material for an electricity storage device according to the present disclosure can color the appearance of the electricity storage device in consideration of various colors of the housing of a product to which the electricity storage device is attached.

[0015] The exterior packaging material for an electricity storage device of the present disclosure will be described in detail below. Note that in this disclosure, a numerical range indicated by "to" means "greater than or equal to" or "less than or equal to." For example, the notation 2 to 15 mm means 2 mm or more and 15 mm or less. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, separately described upper and lower limits, upper and lower limits, or lower and lower limits may each be combined to form a numerical range. Furthermore, in the numerical ranges described in this disclosure, the upper or lower limit value described in a certain numerical range may be replaced with a value shown in the examples.

[0016] Furthermore, in the electrical storage device packaging material of the present disclosure, for example, "exhibiting a white appearance" means that the electrical storage device packaging material is recognized as being white when observed with the naked eye from the outside. More specifically, the "white" in "exhibiting a white appearance" refers to the color that is recognized as being white according to CIE 1976 L * a * b * (CIELAB) chromaticity coordinates, L * The value is 76 or more, preferably 80 or more. * In addition to the value, a *The value is preferably −2 to +2, and b * The value is preferably between -1 and +6.

[0017] 1. Laminated Structure of the Electricity Storage Device Exterior Material As shown in FIG. 1 , for example, the exterior material 10 for an electricity storage device according to the present disclosure is composed of a laminate including a surface coating layer 6, a base layer 1, a barrier layer 3, and a heat-sealable resin layer 4 in this order. In the exterior material 10 for an electricity storage device, the surface coating layer 6 is the outermost layer, and the heat-sealable resin layer 4 is the innermost layer. When assembling an electricity storage device using the exterior material 10 for an electricity storage device and an electricity storage device element, the heat-sealable resin layers 4 of the exterior material 10 for an electricity storage device are placed opposite each other, and the peripheries are heat-sealed to form a space in which the electricity storage device element is housed. In the laminate constituting the exterior material 10 for an electricity storage device according to the present disclosure, the barrier layer 3 is used as the reference, and the heat-sealable resin layer 4 side is the inner side relative to the barrier layer 3, and the surface coating layer 6 side is the outer side relative to the barrier layer 3.

[0018] The packaging material 10 for an electricity storage device according to the present disclosure may be composed of a laminate including, in this order, at least a barrier layer 3 and a heat-sealable resin layer 4. In the laminate, the base material layer 1 is a layer that is provided as needed, and the side of the barrier layer 3 opposite to the heat-sealable resin layer 4 side is the outermost layer, and the heat-sealable resin layer 4 is the innermost layer.

[0019] As shown in Figures 2 and 3, for example, the packaging material 10 for an electricity storage device may have an adhesive layer 2 between the base material layer 1 and the barrier layer 3, if necessary, for the purpose of increasing the adhesion between these layers. Furthermore, as shown in Figure 3, for example, the packaging material 10 for an electricity storage device may have an adhesive layer 5 between the barrier layer 3 and the heat-sealable resin layer 4, if necessary, for the purpose of increasing the adhesion between these layers.

[0020] As will be described later, in the exterior packaging material for an electricity storage device of the present disclosure, the color of the appearance of the exterior material for an electricity storage device can be adjusted by incorporating a colorant into at least one of the layers located outside the barrier layer (for example, a surface coating layer, a base layer, an adhesive layer provided as needed, a colored layer, etc.). Furthermore, the exterior color of the exterior material for an electricity storage device can be adjusted not only by incorporating a colorant, but also by adjusting the type, color, and content of the colorant, or by incorporating an additive (such as a matting agent), and by adjusting the colors of two or more layers, thereby enabling subtle color adjustments taking into account the color of the product's housing.

[0021] In the electrical storage device packaging material of the present disclosure, it is preferable to adjust the color of the appearance of the electrical storage device packaging material as a whole by adjusting the colors of the surface coating layer and the adhesive layer in particular. Note that when the adhesive layer is colorless and transparent (and the base material layer is also colorless and transparent), the color of the barrier layer located inside the adhesive layer affects the color of the appearance of the electrical storage device packaging material as a whole, so it is preferable to also consider the color of the barrier layer.

[0022] In the exterior material for an electricity storage device according to the present disclosure, the color of the exterior is not limited to a specific one, and is adjusted taking into consideration the color of the housing of the product to which the electricity storage device is to be mounted, etc. For example, if the color of the housing of the product to which the electricity storage device is to be mounted is white, the exterior material for an electricity storage device according to the present disclosure can be made to have a similar white appearance.

[0023] The thickness of the laminate constituting the electrical storage device exterior material 10 is not particularly limited, but from the viewpoint of cost reduction, improvement of energy density, etc., examples of the thickness include about 300 μm or less, preferably about 250 μm or less, about 210 μm or less, about 190 μm or less, about 180 μm or less, about 155 μm or less, and about 120 μm or less. Furthermore, from the viewpoint of maintaining the function of the electrical storage device exterior material to protect the electrical storage device elements, the thickness of the laminate constituting the electrical storage device exterior material 10 is preferably about 35 μm or more, about 45 μm or more, about 60 μm or more, about 155 μm or more, and about 190 μm or more. Furthermore, preferred ranges for the laminate constituting the exterior packaging material 10 for an electricity storage device are, for example, about 35 to 300 μm, about 35 to 250 μm, about 35 to 210 μm, about 35 to 190 μm, about 35 to 180 μm, about 35 to 155 μm, about 35 to 120 μm, about 45 to 300 μm, about 45 to 250 μm, about 45 to 210 μm, about 45 to 190 μm, about 45 to 180 μm, about 45 to 155 μm, about 45 to 120 μm, about 60 to 300 μm, about 60 to 250 μm, and about 60 to 300 μm. Examples of the thickness include about 210 μm, about 60 to 190 μm, about 60 to 180 μm, about 60 to 155 μm, about 60 to 120 μm, about 155 to 300 μm, about 155 to 250 μm, about 155 to 210 μm, about 155 to 190 μm, about 155 to 180 μm, about 190 to 300 μm, about 190 to 250 μm, and about 190 to 210 μm. In particular, when making the power storage device lightweight and thin, about 60 to 155 μm is preferred, and when improving formability, about 155 to 190 μm is preferred.

[0024] In the electrical storage device packaging material 10, the ratio of the total thickness of the surface coating layer 6, base material layer 1, adhesive layer 2 provided as needed, barrier layer 3, adhesive layer 5 provided as needed, and heat-sealable resin layer 4 to the thickness (total thickness) of the laminate constituting the electrical storage device packaging material 10 is preferably 90% or more, more preferably 95% or more, and even more preferably 98% or more. As a specific example, when the electrical storage device packaging material 10 of the present disclosure includes the surface coating layer 6, base material layer 1, adhesive layer 2, barrier layer 3, adhesive layer 5, and heat-sealable resin layer 4, the ratio of the total thickness of these layers to the thickness (total thickness) of the laminate constituting the electrical storage device packaging material 10 is preferably 90% or more, more preferably 95% or more, and even more preferably 98% or more. Furthermore, even when the exterior packaging material 10 for an electricity storage device of the present disclosure is a laminate including a surface coating layer 6, a base material layer 1, an adhesive layer 2, a barrier layer 3, and a heat-sealable resin layer 4, the ratio of the total thickness of these layers to the thickness (total thickness) of the laminate constituting the exterior packaging material 10 for an electricity storage device can be, for example, 80% or more, preferably 90% or more, more preferably 95% or more, and even more preferably 98% or more.

[0025] 2. Layers forming the electrical storage device packaging material [Surface coating layer 6] The electrical storage device packaging material of the present disclosure includes a surface coating layer 6 on the substrate layer 1 (the side of the substrate layer 1 opposite to the barrier layer 3) for the purpose of improving at least one of design, electrolyte resistance, scratch resistance, formability, etc. The surface coating layer 6 is a layer located on the outermost layer side of the electrical storage device packaging material when an electrical storage device is assembled using the electrical storage device packaging material.

[0026] When the surface coating layer 6 contains a colorant, the color of the appearance of the electrical storage device packaging material can be adjusted by the surface coating layer 6. In the electrical storage device packaging material of the present disclosure, it is preferable to adjust the color of the appearance of the electrical storage device packaging material as a whole by adjusting the color of the surface coating layer 6. In particular, it is preferable to adjust the color of the appearance of the electrical storage device packaging material as a whole by adjusting the colors of the surface coating layer 6 and the adhesive layer 2.

[0027] The surface coating layer 6 contains a colorant, which allows the electrical storage device exterior material to be colored. Known colorants such as pigments and dyes can be used as the colorant. Only one type of colorant may be used, or two or more types may be mixed together.

[0028] The type of pigment is not particularly limited as long as it can color the surface coating layer. Examples of organic pigments include azo-based, phthalocyanine-based, quinacridone-based, anthraquinone-based, dioxazine-based, indigothioindigo-based, perinone-perylene-based, isoindolenine-based, and benzimidazolone-based pigments. Examples of inorganic pigments include carbon black-based, titanium oxide-based, cadmium-based, lead-based, chromium oxide-based, and iron-based pigments. Other examples include fine powder of mica and fish scale foil.

[0029] Among colorants, titanium oxide is preferred for imparting a white appearance to the exterior material for an electricity storage device, and carbon black is preferred for imparting a black appearance to the exterior material for an electricity storage device.

[0030] The average particle size of the pigment is not particularly limited and may be, for example, about 0.05 to 5 μm, preferably about 0.08 to 2 μm. The average particle size of the pigment is the median diameter measured using a laser diffraction / scattering particle size distribution analyzer. If the primary particle size of the pigment changes, the color of the layer will change, even if the pigment is the same type. For this reason, in the present disclosure, it is also preferable to adjust the primary particle size of the pigment used. The secondary particle size of the pigment is preferably about 2.5 μm or less, more preferably about 2.0 μm or less, even more preferably about 1.8 μm or less, even more preferably about 0.8 μm or less, even more preferably about 0.6 μm or less, and even more preferably 0.4 μm or less, and is preferably about 0.05 μm or more, more preferably about 0.1 μm or more. Preferred ranges include about 0.05 to 2.5 μm, about 0.05 to 2.0 μm, about 0.05 to 1.8 μm, about 0.05 to 0.8 μm, about 0.05 to 0.6 μm, about 0.05 to 0.4 μm, about 0.1 to 2.5 μm, about 0.1 to 2.0 μm, about 0.1 to 1.8 μm, about 0.1 to 0.8 μm, about 0.1 to 0.6 μm, and about 0.1 to 0.4 μm. The primary particle size of the pigment is preferably about 2.5 μm or less, more preferably about 2.0 μm or less, even more preferably about 1.8 μm or less, even more preferably about 0.8 μm or less, even more preferably about 0.6 μm or less, and even more preferably 0.4 μm or less, and is preferably about 0.05 μm or more, more preferably about 0.1 μm or more. Preferred ranges include about 0.05 to 2.5 μm, about 0.05 to 2.0 μm, about 0.05 to 1.8 μm, about 0.05 to 0.8 μm, about 0.05 to 0.6 μm, about 0.05 to 0.4 μm, about 0.1 to 2.5 μm, about 0.1 to 2.0 μm, about 0.1 to 1.8 μm, about 0.1 to 0.8 μm, about 0.1 to 0.6 μm, and about 0.1 to 0.4 μm.

[0031] The content of the colorant in the surface coating layer 6 is preferably about 0.5% by mass or more, more preferably about 1.0% by mass or more, from the viewpoint of appropriately coloring the surface coating layer 6, and is preferably about 50.0% by mass or less, more preferably about 30.0% by mass or less, and even more preferably 20.0% by mass or less, from the viewpoint of appropriately maintaining adhesion to the base layer 1. Preferred ranges include about 0.5 to 50.0% by mass, about 0.5 to 30.0% by mass, about 0.5 to 20.0% by mass, about 1.0 to 50.0% by mass, about 1.0 to 30.0% by mass, and about 1.0 to 20.0% by mass.

[0032] It is also preferable that the surface coating layer 6 contains a matting agent. Among the additives described below, inorganic particles, organic particles, etc. can function as a matting agent, and silica, barium sulfate, etc. are particularly suitable as the matting agent.

[0033] The content of the matting agent in the surface coating layer 6 is preferably about 0.5% by mass or more, more preferably about 1.0% by mass or more, from the viewpoint of reducing the gloss of the surface coating layer 6, and is preferably about 50.0% by mass or less, more preferably about 30.0% by mass or less, and even more preferably 20.0% by mass or less, from the viewpoint of appropriately maintaining adhesion to the base layer 1. Preferred ranges include about 0.5 to 50.0% by mass, about 0.5 to 30.0% by mass, about 0.5 to 20.0% by mass, about 1.0 to 50.0% by mass, about 1.0 to 30.0% by mass, and about 1.0 to 20.0% by mass.

[0034] The surface coating layer 6 can be formed from resins such as polyvinylidene chloride, polyester, polyamide, epoxy resin, acrylic resin, fluororesin, polyurethane, silicone resin, and phenolic resin, or modified versions of these resins. It may also be a copolymer of these resins or a modified version of the copolymer. It may also be a mixture of these resins. When a colorant, a matting agent, or the like is blended into the surface coating layer 6, a resin composition is prepared together with these resins to form the surface coating layer 6. The resin is preferably a curable resin. That is, the surface coating layer 6 is preferably composed of a cured product of a resin composition containing a curable resin.

[0035] When the resin forming the surface coating layer 6 is a curable resin, the resin may be either a one-component curable resin or a two-component curable resin, but is preferably a two-component curable resin. Examples of two-component curable resins include two-component curable polyurethane, two-component curable polyester, and two-component curable epoxy resin. Among these, two-component curable polyurethane is preferred.

[0036] Examples of two-component curing polyurethanes include polyurethanes containing a first component containing a polyol compound and a second component containing an isocyanate compound. Preferred examples of two-component curing polyurethanes include those containing a polyol, such as polyester polyol, polyether polyol, or acrylic polyol, as the first component and an aromatic or aliphatic polyisocyanate as the second component. Examples of polyurethanes include polyurethanes containing an isocyanate compound and a polyurethane compound obtained by reacting a polyol compound with an isocyanate compound in advance. Examples of polyurethanes include polyurethanes containing a polyol compound and a polyurethane compound obtained by reacting a polyol compound with an isocyanate compound in advance. Examples of polyurethanes include polyurethanes obtained by reacting a polyol compound with an isocyanate compound in advance and then curing the polyurethane compound with moisture, such as in the air. Polyol compounds preferably include polyester polyols having hydroxyl groups on the side chains in addition to the terminal hydroxyl groups of the repeating units. Examples of second components include aliphatic, alicyclic, aromatic, and araliphatic isocyanate compounds. Examples of isocyanate compounds include hexamethylene diisocyanate (HDI), xylylene diisocyanate (XDI), isophorone diisocyanate (IPDI), hydrogenated XDI (H6XDI), hydrogenated MDI (H12MDI), tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), and naphthalene diisocyanate (NDI). Also included are polyfunctional isocyanate-modified compounds of one or more of these diisocyanates. Furthermore, polymers (e.g., trimers) can also be used as polyisocyanate compounds. Examples of such polymers include adducts, biurets, and nurates. It should be noted that an aliphatic isocyanate compound refers to an isocyanate that has an aliphatic group but does not have an aromatic ring, an alicyclic isocyanate compound refers to an isocyanate that has an alicyclic hydrocarbon group, and an aromatic isocyanate compound refers to an isocyanate that has an aromatic ring.The surface coating layer 6 is formed from polyurethane, which provides the electrical storage device packaging material with excellent electrolyte resistance.

[0037] The surface coating layer 6 may contain additives such as lubricants, flame retardants, antiblocking agents, antioxidants, light stabilizers, tackifiers, antistatic agents, and pigments, as necessary, in at least one of the surface and interior of the surface coating layer 6, depending on the functionality to be provided to the surface of the surface coating layer 6. Examples of additives include fine particles with an average particle size of approximately 0.5 nm to 5 μm. The average particle size of the additive is the median size measured with a laser diffraction / scattering particle size distribution analyzer.

[0038] The additive may be either an inorganic substance or an organic substance. The shape of the additive is not particularly limited, and examples thereof include spherical, fibrous, plate-like, amorphous, and scaly shapes. As described above, inorganic particles, organic particles, and the like can function as a matting agent.

[0039] Specific examples of additives include talc, silica, graphite, kaolin, montmorillonite, 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-point nylon, acrylate resin, crosslinked acrylic, crosslinked styrene, crosslinked polyethylene, benzoguanamine, gold, aluminum, copper, and nickel. The additives may be used alone or in combination of two or more. Among these additives, silica, barium sulfate, and titanium oxide are preferred from the viewpoints of dispersion stability and cost. Silica is useful as a matting agent. The additives may also be subjected to various surface treatments, such as insulation treatment and high-dispersibility treatment.

[0040] The method for forming the surface coating layer 6 is not particularly limited, and examples thereof include a method of applying a resin to form the surface coating layer 6. As in the case of blending a colorant or a matting agent, when an additive is blended into the surface coating layer 6, a resin composition mixed with the additive may be applied.

[0041] In the exterior packaging material for an electricity storage device of the present disclosure, the color can be suitably adjusted by incorporating a colorant and a matting agent into the surface coating layer 6. The surface coating layer 6 may be a single layer or multiple layers. It is also preferable to adjust the color by using multiple layers for the surface coating layer 6. For example, the color of the surface coating layer 6 can be delicately adjusted by using a laminated structure in which the layer on the substrate layer 1 side contains a colorant (e.g., a white pigment) and the outer layer is uncolored (colorless and transparent) or contains a matting agent, or a laminated structure in which a colorant (e.g., a white pigment) and a matting agent are incorporated into the substrate layer side and a colorant of a different color and a matting agent are incorporated into the outer layer. Among these configurations of the surface coating layer 6, from the viewpoint of adjusting subtle colors, it is preferable that the surface coating layer 6 has a two-layer configuration, and the lamination configuration is preferably a lamination configuration in which a colorant is blended in the layer on the substrate layer 1 side and a colorant of a different color is blended in the outer layer, a lamination configuration in which a colorant and a matting agent are blended in the layer on the substrate layer 1 side and a colorant of a different color and a matting agent are blended in the outer layer, a more preferred lamination configuration is a lamination configuration in which a white pigment is blended in the layer on the substrate layer 1 side and a colorant of a different color is blended in the outer layer, a lamination configuration in which a white pigment and a matting agent are blended in the layer on the substrate layer 1 side and a colorant of a different color and a matting agent are blended in the outer layer, and a still more preferred lamination configuration is a lamination configuration in which titanium oxide and silica are blended in the layer on the substrate layer 1 side and a yellow pigment, a red pigment, and silica are blended in the outer layer.

[0042] In the present disclosure, from the viewpoint of improving the formability of the exterior material for an electrical storage device, it is preferable that a lubricant be present on at least one of the surface and the interior of the surface coating layer 6. The lubricant is not particularly limited, but preferably an amide-based lubricant is used. Specific examples of amide-based lubricants include saturated fatty acid amides, unsaturated fatty acid amides, substituted amides, methylolamides, saturated fatty acid bisamides, unsaturated fatty acid bisamides, fatty acid ester amides, and aromatic bisamides. Specific examples of saturated fatty acid amides include lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, and hydroxystearic acid amide. Specific examples of unsaturated fatty acid amides include oleic acid amide and erucic acid amide. Specific examples of substituted amides include N-oleyl palmitic acid amide, N-stearyl stearic acid amide, N-stearyl oleic acid amide, N-oleyl stearic acid amide, and N-stearyl erucic acid amide. Specific examples of methylolamides include methylol stearic acid amide. Specific examples of saturated fatty acid bisamides include methylene bisstearic acid amide, ethylene biscapric acid amide, ethylene bislauric acid amide, ethylene bisstearic acid amide, ethylene bishydroxystearic acid amide, ethylene bisbehenic acid amide, hexamethylene bisstearic acid amide, hexamethylene bisbehenic acid amide, hexamethylene hydroxystearic acid amide, N,N'-distearyl adipamide, N,N'-distearyl sebacic acid amide, etc. Specific examples of unsaturated fatty acid bisamides include ethylene bisoleic acid amide, ethylene biserucic acid amide, hexamethylene bisoleic acid amide, N,N'-dioleyl adipamide, N,N'-dioleyl sebacic acid amide, etc. Specific examples of fatty acid ester amides include stearamidoethyl stearate, etc. Specific examples of aromatic bisamides include m-xylylene bisstearic acid amide, m-xylylene bishydroxystearic acid amide, and N,N'-distearylisophthalic acid amide.The lubricant may be used alone or in combination of two or more kinds, and it is preferable to use a combination of two or more kinds.

[0043] When a lubricant is present on the surface of the surface coating layer 6, the amount of the lubricant is not particularly limited, but may be, for example, about 3 mg / m 2 or more, preferably about 4 mg / m 2 Above, about 5mg / m 2 The amount of lubricant present on the surface of the surface coating layer 6 is, for example, about 15 mg / m 2 or less, preferably about 14 mg / m 2 Below, about 10mg / m 2 The preferred range of the amount of lubricant present on the surface of the surface coating layer 6 is 3 to 15 mg / m 2 Degree, 3-14mg / m 2 Degree, 3-10mg / m 2 Degree, 4-15mg / m 2 Degree, 4-14mg / m 2 degree, 4-10mg / m 2 degree, 5-15mg / m 2 Degree, 5-14mg / m 2 degree, 5-10mg / m 2 The degree of

[0044] The lubricant present on the surface of the surface coating layer 6 may be a lubricant exuded from the resin that constitutes the surface coating layer 6, or a lubricant applied to the surface of the surface coating layer 6.

[0045] The thickness of the surface coating layer 6 is not particularly limited as long as it exhibits the above-mentioned functions as the surface coating layer 6, and may be, for example, about 0.5 to 10 μm, preferably about 1 to 8 μm, and more preferably about 2 to 6 μm.

[0046] In the production line of an electricity storage device, the surface coating layer of an exterior material for an electricity storage device may be scratched. Scratches cause a change in the glossiness of the surface coating layer, affecting the appearance of the electricity storage device. The risk of scratches can be reduced by using a surface coating layer that is highly scratch-resistant (specifically, one that shows little change in glossiness before and after scratching).

[0047] In addition, in a production line for an electricity storage device, heat is applied to the surface coating layer side of the exterior material for an electricity storage device to heat-seal the heat-sealable resin layers together, thereby sealing the electricity storage device elements. When high temperature and pressure are applied to the surface coating layer, changes in the appearance of the surface coating layer (for example, changes in glossiness of the surface coating layer before and after heat fusion) can be significant. By using a surface coating layer with high heat resistance (specifically, a small change in glossiness before and after heat fusion), changes in the appearance of the heat-sealed parts of the surface coating layer can be suppressed, and an electricity storage device with excellent design can be provided.

[0048] From the viewpoint of the scratch resistance (specifically, suppression of change in glossiness before and after scratching) and heat resistance (specifically, suppression of change in glossiness before and after heat fusion) of the exterior material for an electric storage device of the present disclosure, the glass transition temperature (Tg) of the surface coating layer 6, measured using a rigid pendulum-type physical property tester, is preferably about 120°C or higher, more preferably about 130°C or higher, even more preferably about 135°C or higher, and preferably about 250°C or lower, with preferred ranges including about 120 to 250°C, about 130 to 250°C, and about 135 to 250°C. The higher the glass transition temperature (Tg) of the surface coating layer 6, the harder the surface coating layer 6 is, and the higher the scratch resistance and heat resistance, and the more likely it is that scratches on the exterior material for an electric storage device and changes in appearance due to heat fusion are suppressed. Furthermore, the scratch resistance and heat resistance of the surface coating layer 6 can be improved by adjusting the type, particle size, and content of the matting agent and colorant (especially pigment) that can be contained in the surface coating layer 6, along with the glass transition temperature (Tg) of the surface coating layer 6. For example, the surface coating layer 6 preferably contains both a pigment and a matting agent, and more preferably contains both a pigment and a matting agent in the same layer. The matting agent and pigment are hard and highly heat-resistant, contributing to improved scratch resistance and heat resistance of the surface coating layer 6. Furthermore, the presence of a matting agent and a pigment in the same layer suppresses changes in gloss due to scratches or heat. A preferred combination of a matting agent and a pigment is, for example, a combination of silica and titanium oxide. In particular, by configuring the surface coating layer 6 to have two or more layers and containing both a pigment and a matting agent in each layer, the scratch resistance and heat resistance of the surface coating layer 6 can be further improved in terms of gloss. The glass transition temperature (Tg) of the surface coating layer 6 can be measured as follows.

[0049] <Measurement of Glass Transition Temperature (Tg) of Surface Coating Layer> Using a rigid pendulum-type physical property tester, the glass transition temperature Tg (°C) of the surface coating layer of the exterior material for an electricity storage device is measured under the following measurement conditions. (Measurement Conditions) Measurement device: Commercially available rigid pendulum-type physical property tester Frame used: FRB-400 / disc weight, third from the bottom Edge used: RBP-040 Pretreatment: The AL plate is immersed in an acetone solution and ultrasonically cleaned (5 minutes). The edge is also ultrasonically cleaned for 5 minutes or more. Temperature profile: The temperature is raised from room temperature 25°C to 250°C at a constant temperature over 5 minutes. The aluminum plate and measurement sample are fixed to the heat stage using Kapton tape.

[0050] Furthermore, from the viewpoint of the scratch resistance (specifically, suppression of change in glossiness before and after scratching) and heat resistance (specifically, suppression of change in glossiness before and after heat fusion) of the exterior material for an electricity storage device according to the present disclosure, the elastic modulus EIT of the surface coating layer 6 measured with a microhardness tester (Picodentor) is preferably 2.0 N / mm 2 More preferably, 3.0 N / mm 2 More preferably, 4.0 N / mm 2 or more, and preferably 70 N / mm 2 or less, more preferably 60.0 N / mm 2 or less, more preferably 50.0 N / mm 2 The preferred range is 2.0 to 70.0 N / mm 2 Degree, 2.0-60.0N / mm 2 Degree, 2.0-50.0N / mm 2 Degree, 3.0-70.0N / mm 2 Degree, 3.0-60.0N / mm 2 Degree, 3.0-50.0N / mm 2 Degree, 4.0-70.0N / mm 2 Degree, 4.0-60.0N / mm 2 Degree, 4.0-50.0N / mm 2Examples of the degree of elasticity include the degree of thermal resistance. The higher the elastic modulus EIT of the surface coating layer 6, the higher the scratch resistance and heat resistance of the surface coating layer 6, and the more likely it is that the exterior material for an electrical storage device will be prevented from suffering from scratches or changes in appearance due to heat fusion. Furthermore, the scratch resistance and heat resistance of the surface coating layer 6 can be improved by adjusting the type, particle size, content, etc. of the matting agent and colorant (particularly pigment) that may be contained in the surface coating layer 6, in addition to the elastic modulus EIT of the surface coating layer 6. As described above, for example, the surface coating layer 6 preferably contains both a pigment and a matting agent, and more preferably contains both a pigment and a matting agent in the same layer. The matting agent and pigment are hard and have excellent heat resistance, contributing to improving the scratch resistance and heat resistance of the surface coating layer 6. Furthermore, the presence of the matting agent and the pigment in the same layer prevents changes in gloss due to scratches or heat. A preferred combination of a matting agent and a pigment is, for example, silica and titanium oxide. In particular, by configuring the surface coating layer 6 to have two or more layers and containing both a pigment and a matting agent in each layer, it is possible to further suitably improve the scratch resistance and heat resistance of the surface coating layer 6 from the viewpoint of gloss. The method for measuring the elastic modulus EIT of the surface coating layer 6 is as described below.

[0051] <Elastic modulus EIT of the surface coating layer (N / mm 2 )> Using a microhardness tester (Picodentor), the elastic modulus EIT (N / mm 2 ) is measured. In a measurement temperature environment of 25°C, a diamond square pyramid-shaped Vickers indenter with a facing angle of 136° is pressed into the surface of the surface coating layer from the perpendicular direction, and the elastic modulus EIT is calculated from the obtained load-displacement curve. The average value obtained for 48 measurement positions (including recesses, protrusions, resin parts, and filler parts) on the surface coating layer is taken as the elastic modulus EIT of the surface coating layer. (Measurement conditions) Measurement device: Commercially available Picodenter Indenter: PICO012 (Vickers) Pretreatment: With the surface coating layer facing up, the exterior material for an electricity storage device is fixed onto a slide glass with adhesive, and the slide glass is fixed to the measurement stage with tape. Load control: Maximum 0.1 mN Measurement profile: Load for 10 seconds, hold for 5 seconds, unload for 10 seconds

[0052] Furthermore, from the viewpoint of the scratch resistance (specifically, suppression of change in glossiness before and after scratching) and heat resistance (specifically, suppression of change in glossiness before and after heat fusion) of the exterior material for an electric storage device of the present disclosure, the erosion rate of the surface coating layer 6 measured under the following measurement conditions is preferably 0.15 μm / g or less, more preferably 0.10 μm / g or less, and even more preferably 0.04 μm / g or less. The lower limit is, for example, 0.01 μm / g or more, and preferred ranges are preferably about 0.01 to 0.15 μm / g, about 0.01 to 0.10 μm / g, and about 0.01 to 0.04 μm / g. The lower the erosion rate of the surface coating layer 6, the harder the surface coating layer 6 is, and the less susceptible the exterior material for an electric storage device is to scratches, and changes in appearance tend to be suppressed. Furthermore, the scratch resistance and heat resistance of the surface coating layer 6 can be improved by adjusting the type, particle size, and content of the matting agent and colorant (especially pigment) that may be contained in the surface coating layer 6, along with the erosion rate of the surface coating layer 6. As described above, for example, it is preferable to contain both a pigment and a matting agent, and it is even more preferable to contain both a pigment and a matting agent in the same layer. The matting agent and pigment are hard and have excellent heat resistance, contributing to improved scratch resistance and heat resistance of the surface coating layer 6. Furthermore, the presence of a matting agent and a pigment in the same layer suppresses changes in gloss due to scratches or heat. A preferred combination of a matting agent and a pigment is, for example, a combination of silica and titanium oxide. In particular, by configuring the surface coating layer 6 to have two or more layers and containing both a pigment and a matting agent in each layer, the scratch resistance and heat resistance of the surface coating layer 6 can be further improved in terms of gloss. The erosion rate of the surface coating layer 6 can be measured as follows.

[0053] <Measurement of Erosion Rate of Surface Coating Layer> The erosion rate of the surface coating layer of the exterior material for an electricity storage device is measured by an MSE (micro slurry jet erosion) test under the following measurement conditions. (Measurement Conditions) Measurement equipment: Commercially available MSE test equipment Pretreatment: With the surface coating layer facing up, the exterior material for an electricity storage device is fixed onto a stainless steel plate with double-sided tape, and the stainless steel plate is fixed to the measurement stage. Particles: Polygonal alumina 0.3 μm (MSE-GA-0.3-1 and PGA-0.3-10-00) Slurry projection amount: 2.0 g / time (6.0 g / time for Sample 1 only) Number of slurry projections: 3 to 15 times Projection force: 1 / 10 projection force

[0054] Furthermore, the gloss of the surface coating layer at the heat-sealed position of the exterior material for an electricity storage device according to the present disclosure, as measured in the following <Appearance evaluation of the exterior material for an electricity storage device after heat sealing>, is preferably about 10.0 or less, more preferably about 8.0 or less, and even more preferably about 6.0 or less, and is also preferably about 0.5 or more, more preferably about 1.0 or more, and even more preferably about 1.5 or more. Preferred ranges include about 0.5 to 10.0, about 0.5 to 8.0, about 0.5 to 6.0, about 1.0 to 10.0, about 1.0 to 8.0, about 1.0 to 6.0, about 1.5 to 10.0, about 1.5 to 8.0, and about 1.5 to 6.0. Furthermore, the gloss of the surface coating layer at a position that is not heat-sealed, as measured in the following <Appearance evaluation of exterior material for electricity storage device after heat sealing>, is preferably about 10.0 or less, more preferably about 8.0 or less, and even more preferably about 6.0 or less, and is also preferably about 0.5 or more, more preferably about 1.0 or more, and even more preferably about 1.5 or more. Preferred ranges include about 0.5 to 10.0, about 0.5 to 8.0, about 0.5 to 6.0, about 1.0 to 10.0, about 1.0 to 8.0, about 1.0 to 6.0, about 1.5 to 10.0, about 1.5 to 8.0, and about 1.5 to 6.0.

[0055] In the exterior packaging material for an electricity storage device according to the present disclosure, the absolute value ΔGU of the difference between the gloss of the surface coating layer at the heat-sealed position and the gloss of the surface coating layer at the non-heat-sealed position, as measured in the following <Appearance evaluation of the exterior packaging material for an electricity storage device after heat sealing>, is preferably about 1.0 or less, more preferably about 0.7 or less, even more preferably about 0.3 or less, and is also preferably about 0.0 or more, with preferred ranges being about 0.0 to 1.0, about 0.0 to 0.7, and about 0.0 to 0.3.

[0056] <Evaluation of Appearance of Electricity Storage Device Exterior Material After Heat Sealing> The electricity storage device exterior material is cut into a size of 60 mm (TD) x 120 mm (MD) to prepare a sample. Next, the sample is folded in half in the MD direction so that the heat-sealable resin layers of the sample face each other. Next, the upper and lower surfaces of the sample are sandwiched between 7 mm wide seal heads of a heat sealer (the seal heads on the upper and lower surfaces are in contact with the surface coating layer) so that the heat-sealable resin layers of the folded electricity storage device exterior material are heat-sealed together, and the sample is heat-sealed at a temperature of 210 ° C., a pressure of 1.5 MPa, and for 3 seconds. The gloss (gloss value) of the surface coating layer at the heat-sealed position is measured at a measurement angle of 60 ° using a commercially available gloss meter. The gloss (gloss value) of the surface coating layer at the non-heat-sealed position is also measured. The gloss level is measured in accordance with JIS Z 8741:1997 using a commercially available gloss level meter under the condition of a 60° incident angle of light on the surface to be measured, and the observed Gu value is taken as the gloss level. The average value of the measurement number n = 3 is used as the gloss level (gloss value). The absolute value ΔGU of the difference between the gloss level of the surface coating layer at the position where the sample is heat-sealed and the gloss level of the surface coating layer at the position where the sample is not heat-sealed is calculated.

[0057] Furthermore, the gloss of the surface coating layer at a position where the surface coating layer is rubbed with steel wool, as measured in the following <Scratch Resistance Evaluation of Exterior Material for Electrical Storage Device (Steel Wool Resistance)>, of the exterior material for an electrical storage device according to the present disclosure, is preferably about 10.0 or less, more preferably about 9.0 or less, and even more preferably about 7.0 or less, and is also preferably about 1.0 or more, more preferably about 2.0 or more, and even more preferably about 3.0 or more; preferred ranges include about 1.0 to 10.0, about 1.0 to 9.0, about 1.0 to 7.0, about 2.0 to 10.0, about 2.0 to 9.0, about 2.0 to 7.0, about 3.0 to 10.0, about 3.0 to 9.0, and about 3.0 to 7.0. Furthermore, the gloss of the surface coating layer at a position where the surface coating layer is not rubbed with steel wool, as measured in the following <Scratch Resistance Evaluation of Exterior Materials for Electricity Storage Devices (Steel Wool Resistant)>, is preferably 10.0 or less, more preferably about 8.0 or less, and even more preferably about 6.0 or less, and is also preferably about 0.5 or more, more preferably about 1.0 or more, and even more preferably about 1.5 or more. Preferred ranges include about 0.5 to 10.0, about 0.5 to 8.0, about 0.5 to 6.0, about 1.0 to 10.0, about 1.0 to 8.0, about 1.0 to 6.0, about 1.5 to 10.0, about 1.5 to 8.0, and about 1.5 to 6.0.

[0058] In the exterior material for an electricity storage device according to the present disclosure, the absolute value ΔGU of the difference between the gloss of the surface coating layer at a position where the surface coating layer is rubbed with steel wool and the gloss of the surface coating layer at a position where the surface coating layer is not rubbed with steel wool, as measured in the following <Scratch Resistance Evaluation of Exterior Material for an Electrical Storage Device (Steel Wool Resistance)>, is preferably about 3.0 or less, more preferably about 2.0 or less, and even more preferably about 1.5 or less, and is also preferably about 0.0 or more, with more preferred ranges including about 0.0 to 3.0, about 0.0 to 2.0, and about 0.0 to 1.5.

[0059] <Evaluation of Scratch Resistance of Electricity Storage Device Exterior Material (Steel Wool Resistance)> The heat-fusible resin layer side of the electricity storage device exterior material is brought into contact with a glass plate and fixed with tape. Next, steel wool and a weight (200 g) are placed, in that order, on top of the surface coating layer of the fixed electricity storage device exterior material. With the weight of the weight applied, the surface coating layer is rubbed with the steel wool. The speed when rubbing the surface coating layer with the steel wool is a constant 300 mm / min, and the distance of one round trip is 150 mm. The direction in which the surface coating layer is rubbed with the steel wool is the MD (machine direction) of the electricity storage device exterior material, and the measurement direction of the gloss (gloss value) is also the MD (machine direction) of the electricity storage device exterior material. The gloss (gloss value) is measured at a measurement angle of 60° for the surface coating layer at the position where the surface coating layer was rubbed with the steel wool using a commercially available gloss meter. The gloss (gloss value) is also measured for the surface coating layer at the position where the surface coating layer was not rubbed with the steel wool. The glossiness is measured in accordance with JIS Z 8741:1997 using a commercially available glossiness meter under the condition of an incident angle of light to the surface to be measured of 60°, and the observed Gu value is taken as the glossiness. The average value of the number of measurements n = 3 is adopted as the glossiness (gloss value). The absolute value ΔGU of the difference between the glossiness of the surface coating layer at the position where the surface coating layer is rubbed with steel wool and the glossiness of the surface coating layer at the position where the surface coating layer is not rubbed with steel wool is calculated.

[0060] [Substrate layer 1] In the present disclosure, the substrate layer 1 is a layer provided for the purpose of exhibiting the function as a substrate of the packaging material for an electricity storage device, etc. The substrate layer 1 is located on the outer layer side of the packaging material for an electricity storage device.

[0061] The material forming the substrate layer 1 is not particularly limited as long as it functions as a substrate, i.e., has at least insulating properties. The substrate layer 1 can be formed using, for example, a resin, which may contain the above-mentioned colorant, additives, etc. When the substrate layer contains a colorant, the substrate layer can adjust the color of the appearance of the exterior material for an electricity storage device. The substrate layer may also be colorless and transparent.

[0062] When the substrate layer 1 is formed of a resin, the substrate layer 1 can be formed of, for example, a resin film. When the substrate layer 1 is formed of a resin film, a pre-formed resin film may be used as the substrate layer 1 when the substrate layer 1 is laminated with the barrier layer 3 or the like to produce the electrical storage device packaging material 10 of the present disclosure. Alternatively, the resin forming the substrate layer 1 may be formed into a film on the surface of the barrier layer 3 or the like by extrusion molding, coating, or the like to form the substrate layer 1 formed of a resin film. The resin film may be an unstretched film or a stretched film. Examples of stretched films include uniaxially stretched films and biaxially stretched films, with biaxially stretched films being preferred. Examples of stretching methods for forming a biaxially stretched film include sequential biaxial stretching, inflation, and simultaneous biaxial stretching. Examples of methods for applying the resin include roll coating, gravure coating, and extrusion coating.

[0063] Examples of resins that form the base layer 1 include polyester, polyamide, polyolefin, epoxy resin, acrylic resin, fluororesin, polyurethane, silicone resin, and phenolic resin, as well as modified versions of these resins. The resin that forms the base layer 1 may also be a copolymer of these resins, a modified version of the copolymer, or a mixture of these resins.

[0064] The base layer 1 preferably contains these resins as the main component, and more preferably contains polyester or polyamide as the main component. Here, "main component" means that the content of the resin component contained in the base layer 1 is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more. For example, "the base layer 1 contains polyester or polyamide as the main component" means that the content of polyester or polyamide among the resin components contained in the base layer 1 is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more.

[0065] Of these, polyester and polyamide are preferred as the resin for forming the base layer 1.

[0066] Specific examples of polyesters include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, and copolymer polyesters. Examples of copolymer polyesters include copolymer polyesters in which ethylene terephthalate is the main repeating unit. Specific examples include copolymer polyesters in which ethylene terephthalate is the main repeating unit and is polymerized with ethylene isophthalate (hereinafter abbreviated as polyethylene (terephthalate / isophthalate)), polyethylene (terephthalate / adipate), polyethylene (terephthalate / sodium sulfoisophthalate), polyethylene (terephthalate / sodium isophthalate), polyethylene (terephthalate / phenyl-dicarboxylate), and polyethylene (terephthalate / decanedicarboxylate). These polyesters may be used alone or in combination of two or more.

[0067] Specific examples of polyamides include aliphatic polyamides such as nylon 6, nylon 66, nylon 610, nylon 12, nylon 46, and copolymers of nylon 6 and nylon 66; hexamethylenediamine-isophthalic acid-terephthalic acid copolymer polyamides such as nylon 6I, nylon 6T, nylon 6IT, and nylon 6I6T (where I represents isophthalic acid and T represents terephthalic acid) containing structural units derived from terephthalic acid and / or isophthalic acid; and aromatic polyamides such as polyamide MXD6 (polymetaxylylene adipamide); alicyclic polyamides such as polyamide PACM6 (polybis(4-aminocyclohexyl)methane adipamide); polyamides copolymerized with a lactam component or an isocyanate component such as 4,4'-diphenylmethane-diisocyanate; polyesteramide copolymers and polyetheresteramide copolymers, which are copolymers of copolymerized polyamides with polyesters or polyalkylene ether glycols; and polyamides such as copolymers of these copolymers. These polyamides may be used alone or in combination of two or more.

[0068] The base layer 1 preferably includes at least one of a polyester film, a polyamide film, and a polyolefin film, and preferably includes at least one of a stretched polyester film, a stretched polyamide film, and a stretched polyolefin film, and more preferably includes at least one of a stretched polyethylene terephthalate film, a stretched polybutylene terephthalate film, a stretched nylon film, and a stretched polypropylene film, and even more preferably includes at least one of a biaxially oriented polyethylene terephthalate film, a biaxially oriented polybutylene terephthalate film, a biaxially oriented nylon film, and a biaxially oriented polypropylene film.

[0069] The base material layer 1 may be a single layer or may be composed of two or more layers. When the base material layer 1 is composed of two or more layers, the base material layer 1 may be a laminate in which resin films are laminated with an adhesive or the like, or a laminate of resin films formed by co-extrusion of resins into two or more layers. Furthermore, a laminate of resin films formed by co-extrusion of resins into two or more layers may be used as the base material layer 1 without being stretched, or may be uniaxially or biaxially stretched to form the base material layer 1.

[0070] Specific examples of the laminate of two or more resin films in the base layer 1 include a laminate of a polyester film and a nylon film, a laminate of two or more nylon films, and a laminate of two or more polyester films. A laminate of a stretched nylon film and a stretched polyester film, a laminate of two or more stretched nylon films, or a laminate of two or more stretched polyester films is preferred. For example, when the base layer 1 is a laminate of two resin films, a laminate of a polyester resin film and a polyester resin film, a laminate of a polyamide resin film and a polyamide resin film, or a laminate of a polyester resin film and a polyamide resin film is preferred. A laminate of a polyethylene terephthalate film and a polyethylene terephthalate film, a laminate of a nylon film and a nylon film, or a laminate of a polyethylene terephthalate film and a nylon film is more preferred. Furthermore, since polyester resins are less likely to discolor when an electrolytic solution adheres to their surface, it is preferred that the polyester resin film be located as the outermost layer of the base layer 1 when the base layer 1 is a laminate of two or more resin films. In the laminate of a polyester resin film and a polyamide resin film, preferred ranges of the thickness of the polyester resin film are about 2 to 33 μm, about 2 to 28 μm, about 2 to 23 μm, about 2 to 18 μm, about 2 to 11 μm, about 2 to 8 μm, about 10 to 33 μm, about 10 to 28 μm, about 10 to 23 μm, about 10 to 18 μm, about 18 to 33 μm, and about 18 to 28 μm. and about 18 to 23 μm. Preferred ranges of the thickness of the polyamide resin film include about 2 to 33 μm, about 2 to 28 μm, about 2 to 23 μm, about 2 to 18 μm, about 2 to 11 μm, about 2 to 8 μm, about 10 to 33 μm, about 10 to 28 μm, about 10 to 23 μm, about 10 to 18 μm, about 18 to 33 μm, about 18 to 28 μm, and about 18 to 23 μm.

[0071] When the base layer 1 is a laminate of two or more resin film layers, the two or more resin film layers may be laminated via an adhesive. Examples of preferred adhesives include those similar to those exemplified for adhesive layer 2 described below. The method for laminating two or more resin film layers is not particularly limited, and known methods can be used, such as dry lamination, sandwich lamination, extrusion lamination, and thermal lamination, with dry lamination being preferred. When laminating using the dry lamination method, it is preferable to use a polyurethane adhesive as the adhesive. In this case, the thickness of the adhesive may be, for example, about 2 to 5 μm. Alternatively, an anchor coat layer may be formed on the resin film before lamination. Examples of the anchor coat layer include those similar to those exemplified for adhesive layer 2 described below. In this case, the thickness of the anchor coat layer may be, for example, about 0.01 to 1.0 μm.

[0072] Furthermore, additives such as lubricants, flame retardants, antiblocking agents, antioxidants, light stabilizers, tackifiers, antistatic agents, and colorants may be present on at least one of the surface and the interior of the base material layer 1. Only one type of additive may be used, or two or more types may be mixed and used.

[0073] In the present disclosure, from the viewpoint of improving the formability of the exterior material for an electrical storage device, it is preferable that a lubricant be present on at least one of the surface and the interior of the base material layer 1. The lubricant is not particularly limited, but preferably an amide-based lubricant is used. Specific examples of amide-based lubricants include saturated fatty acid amides, unsaturated fatty acid amides, substituted amides, methylolamides, saturated fatty acid bisamides, unsaturated fatty acid bisamides, fatty acid ester amides, and aromatic bisamides. Specific examples of saturated fatty acid amides include lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, and hydroxystearic acid amide. Specific examples of unsaturated fatty acid amides include oleic acid amide and erucic acid amide. Specific examples of substituted amides include N-oleyl palmitic acid amide, N-stearyl stearic acid amide, N-stearyl oleic acid amide, N-oleyl stearic acid amide, and N-stearyl erucic acid amide. Specific examples of methylolamides include methylol stearic acid amide. Specific examples of saturated fatty acid bisamides include methylene bisstearic acid amide, ethylene biscapric acid amide, ethylene bislauric acid amide, ethylene bisstearic acid amide, ethylene bishydroxystearic acid amide, ethylene bisbehenic acid amide, hexamethylene bisstearic acid amide, hexamethylene bisbehenic acid amide, hexamethylene hydroxystearic acid amide, N,N'-distearyl adipamide, N,N'-distearyl sebacic acid amide, etc. Specific examples of unsaturated fatty acid bisamides include ethylene bisoleic acid amide, ethylene biserucic acid amide, hexamethylene bisoleic acid amide, N,N'-dioleyl adipamide, N,N'-dioleyl sebacic acid amide, etc. Specific examples of fatty acid ester amides include stearamidoethyl stearate, etc. Specific examples of aromatic bisamides include m-xylylene bisstearic acid amide, m-xylylene bishydroxystearic acid amide, and N,N'-distearylisophthalic acid amide.The lubricant may be used alone or in combination of two or more kinds, and it is preferable to use a combination of two or more kinds.

[0074] When a lubricant is present on the surface of the base layer 1, the amount of the lubricant is not particularly limited, but may be, for example, about 3 mg / m 2 or more, preferably about 4 mg / m 2 Above, about 5mg / m 2 The amount of lubricant present on the surface of the base layer 1 is, for example, about 15 mg / m 2 or less, preferably about 14 mg / m 2 Below, about 10mg / m 2 The preferred range of the amount of lubricant present on the surface of the base layer 1 is 3 to 15 mg / m 2 Degree, 3-14mg / m 2 Degree, 3-10mg / m 2 Degree, 4-15mg / m 2 Degree, 4-14mg / m 2 degree, 4-10mg / m 2 degree, 5-15mg / m 2 Degree, 5-14mg / m 2 degree, 5-10mg / m 2 The degree of

[0075] The lubricant present on the surface of the base layer 1 may be a lubricant exuded from the resin constituting the base layer 1, or a lubricant applied to the surface of the base layer 1.

[0076] The thickness of the substrate layer 1 is not particularly limited as long as it functions as a substrate, but may be, for example, about 3 μm or more, preferably about 10 μm or more. The thickness of the substrate layer 1 may be, for example, about 50 μm or less, preferably about 35 μm or less, about 11 μm or less, or about 8 μm or less. Preferred thickness ranges for the substrate layer 1 include about 3 to 50 μm, about 3 to 35 μm, about 3 to 11 μm, about 3 to 8 μm, about 10 to 50 μm, and about 10 to 35 μm. In particular, when reducing the weight and thickness of an electric storage device, about 3 to 35 μm, about 3 to 11 μm, or about 3 to 8 μm is preferred, and when improving formability, about 35 to 50 μm is preferred. When the substrate layer 1 is a laminate of two or more resin films, the thickness of each resin film constituting each layer is not particularly limited, but may be, for example, about 2 μm or more, preferably about 10 μm or more, or about 18 μm or more. The thickness of the resin film constituting each layer is, for example, about 33 μm or less, preferably about 28 μm or less, about 23 μm or less, about 18 μm or less, about 11 μm or less, or about 8 μm or less. Preferred ranges for the thickness of the resin film constituting each layer include about 2 to 33 μm, about 2 to 28 μm, about 2 to 23 μm, about 2 to 18 μm, about 2 to 11 μm, about 2 to 8 μm, about 10 to 33 μm, about 10 to 28 μm, about 10 to 23 μm, about 10 to 18 μm, about 10 to 11 μm, about 18 to 33 μm, about 18 to 28 μm, and about 18 to 23 μm.

[0077] When a colorant is contained in the base layer 1, the content of the colorant is preferably 40.0% by mass or less, more preferably 30.0% by mass or less, and even more preferably 20.0% by mass or less, and is preferably 1.0% by mass or more, more preferably 3.0% by mass or more, and even more preferably 5.0% by mass or more. Preferred ranges include about 1.0 to 40.0% by mass, about 1.0 to 30.0% by mass, about 1.0 to 20.0% by mass, about 3.0 to 40.0% by mass, about 3.0 to 30.0% by mass, about 3.0 to 20.0% by mass, about 5.0 to 40.0% by mass, about 5.0 to 30.0% by mass, and about 5.0 to 20.0% by mass.

[0078] [Adhesive Layer 2] In the packaging material for an electricity storage device according to the present disclosure, the adhesive layer 2 is a layer that is provided between the base layer 1 and the barrier layer 3 as needed for the purpose of increasing the adhesion between them.

[0079] In the electrical storage device packaging material of the present disclosure, it is preferable to adjust the color of the appearance of the electrical storage device packaging material as a whole by adjusting the color of the adhesive layer. Furthermore, it is preferable to adjust the color of the appearance of the electrical storage device packaging material as a whole by adjusting the colors of the surface coating layer and the adhesive layer. Note that when the adhesive layer is colorless and transparent (and the base layer is also colorless and transparent), the color of the barrier layer located inside the adhesive layer affects the color of the appearance of the electrical storage device packaging material as a whole.

[0080] The adhesive layer 2 contains a colorant, which allows the exterior material for an electrical storage device to be colored. Known colorants such as pigments and dyes can be used as the colorant. A single colorant may be used, or two or more colorants may be mixed. Specific examples of colorants contained in the adhesive layer 2 include those exemplified in the [Surface coating layer 6] section. The preferred content of the colorant contained in the adhesive layer 2 is also the same as that described in the [Surface coating layer 6] section.

[0081] The adhesive layer 2 is formed from an adhesive capable of bonding the base material layer 1 and the barrier layer 3. When the adhesive layer 2 is to be colored, a colorant is blended into the adhesive. The adhesive used to form the adhesive layer 2 is not limited, and may be any of a chemical reaction type, a solvent volatilization type, a hot melt type, a thermocompression type, etc. Furthermore, it may be a two-component curing adhesive (two-component adhesive), a one-component curing adhesive (one-component adhesive), or a resin that does not involve a curing reaction. Furthermore, the adhesive layer 2 may be a single layer or a multilayer.

[0082] Specific examples of adhesive components contained in the adhesive include polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, and copolymer polyesters; polyethers; polyurethanes; epoxy resins; phenolic resins; polyamides such as nylon 6, nylon 66, nylon 12, and copolymer polyamides; polyolefin-based resins such as polyolefins, cyclic polyolefins, acid-modified polyolefins, and acid-modified cyclic polyolefins; polyvinyl acetate; cellulose; (meth)acrylic resins; polyimides; polycarbonates; amino resins such as urea resins and melamine resins; rubbers such as chloroprene rubber, nitrile rubber, and styrene-butadiene rubber; and silicone resins. These adhesive components may be used alone or in combination with two or more. Among these adhesive components, polyurethane adhesives are preferred. Furthermore, the adhesive strength of these adhesive component resins can be increased by using an appropriate curing agent in combination. The curing agent is selected appropriately from polyisocyanates, multifunctional epoxy resins, oxazoline group-containing polymers, polyamine resins, acid anhydrides, and the like, depending on the functional groups possessed by the adhesive components.

[0083] Examples of polyurethane adhesives include polyurethane adhesives containing a first part containing a polyol compound and a second part containing an isocyanate compound. Two-component curing polyurethane adhesives are preferred, with a polyol such as polyester polyol, polyether polyol, or acrylic polyol as the first part and an aromatic or aliphatic polyisocyanate as the second part. Examples of polyurethane adhesives include polyurethane adhesives containing a polyurethane compound obtained by reacting a polyol compound with an isocyanate compound in advance, and an isocyanate compound. Examples of polyurethane adhesives include polyurethane adhesives containing a polyurethane compound obtained by reacting a polyol compound with an isocyanate compound in advance, and a polyol compound. Examples of polyurethane adhesives include polyurethane adhesives obtained by reacting a polyurethane compound obtained by reacting a polyol compound with an isocyanate compound in advance with moisture, such as in the air, and then curing the polyurethane compound. Polyester polyols having hydroxyl groups on the side chains in addition to terminal hydroxyl groups in the repeating unit are preferably used as the polyol compound. Examples of the second part include aliphatic, alicyclic, aromatic, and araliphatic isocyanate compounds. Examples of isocyanate compounds include hexamethylene diisocyanate (HDI), xylylene diisocyanate (XDI), isophorone diisocyanate (IPDI), hydrogenated XDI (H6XDI), hydrogenated MDI (H12MDI), tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), and naphthalene diisocyanate (NDI). Also included are polyfunctional isocyanate-modified compounds of one or more of these diisocyanates. Multimers (e.g., trimers) can also be used as polyisocyanate compounds. Examples of such multimers include adducts, biurets, and nurates. Forming the adhesive layer 2 using a polyurethane adhesive provides the electrical storage device exterior material with excellent electrolyte resistance, preventing peeling of the base layer 1 even when the electrolyte adheres to the side surface.

[0084] The thickness of the adhesive layer 2 is not particularly limited as long as it can bond the base layer 1 and the barrier layer 3, but is, for example, about 1 μm or more, about 2 μm or more. The thickness of the adhesive layer 2 is, for example, about 10 μm or less, about 5 μm or less. Preferred ranges for the thickness of the adhesive layer 2 include about 1 to 10 μm, about 1 to 5 μm, about 2 to 10 μm, and about 2 to 5 μm.

[0085] The adhesive layer 2 may contain other components besides the colorant as long as they do not impair adhesiveness, and may contain thermoplastic elastomers, tackifiers, fillers, and the like.

[0086] [Colored Layer] The colored layer is a layer (not shown) that is provided between the base material layer 1 and the barrier layer 3 as needed. When the adhesive layer 2 is provided, a colored layer may be provided between the base material layer 1 and the adhesive layer 2, or between the adhesive layer 2 and the barrier layer 3. Alternatively, a colored layer may be provided on the outside of the base material layer 1. By providing a colored layer, the packaging material for an electricity storage device can be colored.

[0087] The colored layer can be formed, for example, by applying ink containing a colorant to the surface of the base layer 1 or the surface of the barrier layer 3. Known colorants such as pigments and dyes can be used as the colorant. Only one type of colorant may be used, or two or more types may be mixed together.

[0088] Specific examples of the colorant contained in the colored layer include the same as those exemplified in the section [Adhesive layer 2].

[0089] The content of the colorant in the colored layer is not particularly limited as long as the electrical storage device exterior material is colored, and from the viewpoint of appropriate coloring, it is preferably about 0.5% by mass or more, more preferably about 1.0% by mass or more, and from the viewpoint of appropriate formation of the colored layer, it is preferably about 50.0% by mass or less, more preferably about 30.0% by mass or less, and even more preferably about 20.0% by mass or less, and preferred ranges include about 0.5 to 50.0% by mass, about 0.5 to 30.0% by mass, about 0.5 to 20.0% by mass, about 1.0 to 50.0% by mass, about 1.0 to 30.0% by mass, and about 1.0 to 20.0% by mass.

[0090] The thickness of the colored layer is not particularly limited as long as it can bond the base material layer 1 and the barrier layer 3, but is, for example, about 1 μm or more, or about 2 μm or more. The thickness of the adhesive layer 2 is, for example, about 10 μm or less, or about 5 μm or less. Preferred ranges for the thickness of the adhesive layer 2 include about 1 to 10 μm, about 1 to 5 μm, about 2 to 10 μm, and about 2 to 5 μm.

[0091] [Barrier Layer 3] In the packaging material for an electricity storage device, the barrier layer 3 is a layer that at least prevents the penetration of moisture.

[0092] Examples of the barrier layer 3 include metal foils, vapor-deposited films, and resin layers having barrier properties. Vapor-deposited films include metal vapor-deposited films, inorganic oxide vapor-deposited films, and carbon-containing inorganic oxide vapor-deposited films. Resin layers include fluorine-containing resins such as polyvinylidene chloride, polymers mainly composed of chlorotrifluoroethylene (CTFE), polymers mainly composed of tetrafluoroethylene (TFE), polymers having fluoroalkyl groups, and polymers mainly composed of fluoroalkyl units, as well as ethylene-vinyl alcohol copolymers. Examples of the barrier layer 3 also include resin films comprising at least one of these vapor-deposited films and resin layers. The barrier layer 3 may include multiple layers. The barrier layer 3 preferably includes a layer composed of a metal material. Specific examples of metal materials constituting the barrier layer 3 include aluminum alloys, stainless steel, titanium steel, and steel plates. When used as a metal foil, the barrier layer 3 preferably includes at least one of aluminum alloy foil and stainless steel foil.

[0093] In the barrier layer 3, the layer made of the aforementioned metal material may contain recycled metal material. Examples of recycled metal material include recycled aluminum alloy, stainless steel, titanium steel, and steel plate. These recycled materials can be obtained by known methods. Recycled aluminum alloy material can be obtained, for example, by the manufacturing method described in International Publication No. 2022 / 092231. The barrier layer 3 may be made of recycled material alone, or may be made of a mixture of recycled and virgin material. Note that recycled metal material refers to metal material that has been made reusable by collecting, isolating, and refining various products used in the market or waste from manufacturing processes. Furthermore, virgin metal material refers to new metal material refined from natural metal resources (raw materials) and is not recycled material.

[0094] From the viewpoint of improving the formability of the electrical storage device packaging material, the aluminum alloy foil is preferably a soft aluminum alloy foil made of, for example, an annealed aluminum alloy, and from the viewpoint of further improving formability, an iron-containing aluminum alloy foil is preferred. In the iron-containing aluminum alloy foil (100% by mass), the iron content is preferably 0.1 to 9.0% by mass, more preferably 0.5 to 2.0% by mass. By having an iron content of 0.1% by mass or more, an electrical storage device packaging material with better formability can be obtained. By having an iron content of 9.0% by mass or less, an electrical storage device packaging material with better flexibility can be obtained. Examples of soft aluminum alloy foils include aluminum alloy foils having a composition specified in JIS H4160:1994 A8021H-O, JIS H4160:1994 A8079H-O, JIS H4000:2014 A8021P-O, or JIS H4000:2014 A8079P-O. Silicon, magnesium, copper, manganese, etc. may be added as needed. Softening can be achieved by annealing or other methods.

[0095] Examples of the stainless steel foil include austenitic, ferritic, austenitic-ferritic, martensitic, and precipitation hardened stainless steel foils. From the viewpoint of providing an exterior material for an electricity storage device that has excellent formability, the stainless steel foil is preferably made of austenitic stainless steel.

[0096] Specific examples of austenitic stainless steels that form the stainless steel foil include SUS304, SUS301, and SUS316L, with SUS304 being particularly preferred.

[0097] In the case of a metal foil, the thickness of the barrier layer 3 should be sufficient to at least function as a barrier layer that prevents moisture penetration, and may be, for example, approximately 9 to 200 μm. The thickness of the barrier layer 3 is preferably approximately 85 μm or less, more preferably approximately 50 μm or less, even more preferably approximately 40 μm or less, and particularly preferably approximately 35 μm or less. The thickness of the barrier layer 3 is preferably approximately 10 μm or more, even more preferably approximately 20 μm or more, and more preferably approximately 25 μm or more. Preferred thickness ranges for the barrier layer 3 include approximately 10 to 85 μm, approximately 10 to 50 μm, approximately 10 to 40 μm, approximately 10 to 35 μm, approximately 20 to 85 μm, approximately 20 to 50 μm, approximately 20 to 40 μm, approximately 20 to 35 μm, approximately 25 to 85 μm, approximately 25 to 50 μm, approximately 25 to 40 μm, and approximately 25 to 35 μm. When the barrier layer 3 is made of an aluminum alloy foil, the above-mentioned range is particularly preferable. From the viewpoint of imparting high formability and high rigidity to the packaging material 10 for an electricity storage device, the thickness of the barrier layer 3 is preferably about 35 μm or more, more preferably about 45 μm or more, even more preferably about 50 μm or more, and still more preferably about 55 μm or more, and is also preferably about 200 μm or less, more preferably about 85 μm or less, even more preferably about 75 μm or less, and still more preferably about 70 μm or less. Preferred ranges are approximately 35 to 200 μm, approximately 35 to 85 μm, approximately 35 to 75 μm, approximately 35 to 70 μm, approximately 45 to 200 μm, approximately 45 to 85 μm, approximately 45 to 75 μm, approximately 45 to 70 μm, approximately 50 to 200 μm, approximately 50 to 85 μm, approximately 50 to 75 μm, approximately 50 to 70 μm, approximately 55 to 200 μm, approximately 55 to 85 μm, approximately 55 to 75 μm, and approximately 55 to 70 μm. The high formability of the exterior packaging material 10 for an electricity storage device facilitates deep drawing, which can contribute to increasing the capacity of the electricity storage device. Furthermore, while increasing the capacity of an electricity storage device increases the weight of the electricity storage device, the increased rigidity of the exterior packaging material 10 for an electricity storage device can contribute to high sealing performance of the electricity storage device.In particular, when the barrier layer 3 is composed of a stainless steel foil, the thickness of the stainless steel foil is preferably about 60 μm or less, more preferably about 50 μm or less, even more preferably about 40 μm or less, even more preferably about 30 μm or less, and particularly preferably about 25 μm or less. The thickness of the stainless steel foil is preferably about 10 μm or more, more preferably about 15 μm or more. Preferred ranges for the thickness of the stainless steel foil include about 10 to 60 μm, about 10 to 50 μm, about 10 to 40 μm, about 10 to 30 μm, about 10 to 25 μm, about 15 to 60 μm, about 15 to 50 μm, about 15 to 40 μm, about 15 to 30 μm, and about 15 to 25 μm.

[0098] Furthermore, when the barrier layer 3 is a metal foil, it is preferable that a corrosion-resistant coating be provided on at least the surface opposite the substrate layer to prevent dissolution and corrosion. The barrier layer 3 may be provided with a corrosion-resistant coating on both sides. Here, the corrosion-resistant coating refers to a thin film that is provided with corrosion resistance (e.g., acid resistance, alkali resistance, etc.) by performing, for example, a hydrothermal conversion treatment such as boehmite treatment, a chemical conversion treatment, an anodizing treatment, a plating treatment of nickel or chromium, or a corrosion prevention treatment by applying a coating agent on the surface of the barrier layer. Specifically, the corrosion-resistant coating refers to a coating that improves the acid resistance of the barrier layer (acid-resistant coating), a coating that improves the alkali resistance of the barrier layer (alkali-resistant coating), etc. The treatment for forming the corrosion-resistant coating may be one type or a combination of two or more types. Furthermore, not only one layer but also multiple layers can be formed. Furthermore, among these treatments, the hydrothermal conversion treatment and the anodizing treatment are treatments that dissolve the metal foil surface with a treatment agent to form a metal compound with excellent corrosion resistance. These treatments may be included in the definition of chemical conversion treatment. In addition, when the barrier layer 3 is provided with a corrosion-resistant coating, the barrier layer 3 includes the corrosion-resistant coating.

[0099] The corrosion-resistant coating prevents delamination between the barrier layer (e.g., aluminum alloy foil) and the substrate layer during molding of the electrical storage device packaging material, prevents dissolution and corrosion of the barrier layer surface due to hydrogen fluoride produced by a reaction between the electrolyte and water, and in particular prevents dissolution and corrosion of aluminum oxide present on the barrier layer surface when the barrier layer is an aluminum alloy foil, and also improves the adhesion (wettability) of the barrier layer surface, thereby preventing delamination between the substrate layer and the barrier layer during heat sealing and molding.

[0100] Various corrosion-resistant coatings formed by chemical conversion treatments are known, including mainly corrosion-resistant coatings containing at least one of phosphates, chromates, fluorides, triazine thiol compounds, and rare earth oxides. Examples of chemical conversion treatments using phosphates and chromates include chromate chromate treatment, phosphate chromate treatment, phosphate-chromate treatment, and chromate treatment. Examples of chromium compounds used in these treatments include chromium nitrate, chromium fluoride, chromium sulfate, chromium acetate, chromium oxalate, chromium biphosphate, chromate acetylacetate, chromium chloride, and potassium chromium sulfate. Examples of phosphorus compounds used in these treatments include sodium phosphate, potassium phosphate, ammonium phosphate, and polyphosphoric acid. Examples of chromate treatments include etching chromate treatment, electrolytic chromate treatment, and paint-on chromate treatment, with paint-on chromate treatment being preferred. This paint-type chromate treatment involves first degreasing at least the inner surface of a barrier layer (e.g., an aluminum alloy foil) using a well-known method such as alkali immersion, electrolytic cleaning, acid pickling, electrolytic pickling, or acid activation, and then coating the degreased surface with a treatment solution containing, as its main component, a metal phosphate such as chromium (Cr) phosphate, titanium (Ti) phosphate, zirconium (Zr) phosphate, or zinc (Zn) phosphate, or a mixture of these metal salts, or a treatment solution containing, as its main component, a nonmetallic phosphate and a mixture of these nonmetallic salts, or a mixture of these with a synthetic resin, by a well-known coating method such as roll coating, gravure printing, or immersion, followed by drying. The treatment solution can be, for example, water, alcoholic solvents, hydrocarbon solvents, ketone solvents, ester solvents, or ether solvents, with water being preferred. Examples of the resin component used here include polymers such as phenolic resins and acrylic resins, and chromate treatment using an aminated phenol polymer having repeating units represented by the following general formulas (1) to (4). The aminated phenol polymer may contain one type of repeating unit represented by the following general formulas (1) to (4) alone, or two or more types of repeating units may be contained in any combination.The acrylic resin is preferably polyacrylic acid, an acrylic acid methacrylic acid ester copolymer, an acrylic acid maleic acid copolymer, an acrylic acid styrene copolymer, or a derivative thereof such as a sodium salt, an ammonium salt, or an amine salt. A derivative of polyacrylic acid, such as an ammonium salt, a sodium salt, or an amine salt of polyacrylic acid, is particularly preferred. In the present disclosure, polyacrylic acid refers to a polymer of acrylic acid. The acrylic resin is also preferably a copolymer of acrylic acid and a dicarboxylic acid or a dicarboxylic acid anhydride, or an ammonium salt, a sodium salt, or an amine salt of a copolymer of acrylic acid and a dicarboxylic acid or a dicarboxylic acid anhydride. Only one type of acrylic resin may be used, or two or more types may be mixed and used.

[0101]

[0102]

[0103]

[0104]

[0105] 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. 1 and R 2 are the same or different and represent a hydroxy group, an alkyl group, or a hydroxyalkyl group. 1 and R 2 Examples of the alkyl group represented by X and R include linear or branched alkyl groups having 1 to 4 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and tert-butyl. 1 and R 2Examples of the hydroxyalkyl group represented by the formula (1) include a linear or branched alkyl group having 1 to 4 carbon atoms substituted with one hydroxy group, such as a hydroxymethyl group, a 1-hydroxyethyl group, a 2-hydroxyethyl group, a 1-hydroxypropyl group, a 2-hydroxypropyl group, a 3-hydroxypropyl group, a 1-hydroxybutyl group, a 2-hydroxybutyl group, a 3-hydroxybutyl group, and a 4-hydroxybutyl group. 1 and R 2 The alkyl group and hydroxyalkyl group represented by the formula (1) may be the same or different. In the formulae (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 repeating units represented by the formulae (1) to (4) is preferably about 500 to 1,000,000, for example, and more preferably about 1,000 to 20,000. The aminated phenol polymer can be prepared, for example, by polycondensing a phenol compound or a naphthol compound with formaldehyde to produce a polymer comprising repeating units represented by the formula (1) or (3), and then polycondensing the polymer with formaldehyde and an amine (R 1 R 2 NH) to form a functional group (-CHNR 1 R 2 The aminated phenol polymers may be used singly or in combination of two or more.

[0106] Another example of a corrosion-resistant coating is a thin film formed by a coating-type corrosion prevention treatment in which a coating agent containing at least one selected from the group consisting of a rare earth element oxide sol, an anionic polymer, and a cationic polymer is applied. The coating agent may further contain phosphoric acid or a phosphate salt, and a crosslinking agent for crosslinking the polymer. The rare earth element oxide sol contains rare earth element oxide fine particles (e.g., particles with an average particle size of 100 nm or less) dispersed in a liquid dispersion medium. Examples of rare earth element oxides include cerium oxide, yttrium oxide, neodymium oxide, and lanthanum oxide, with cerium oxide being preferred from the perspective of further improving adhesion. The rare earth element oxide contained in the corrosion-resistant coating can be used alone or in combination of two or more. Examples of liquid dispersion media for the rare earth element oxide sol include various solvents such as water, alcohol-based solvents, hydrocarbon-based solvents, ketone-based solvents, ester-based solvents, and ether-based solvents, with water being preferred. Preferred examples of cationic polymers include polyethyleneimine, ionic polymer complexes consisting of polyethyleneimine and a polymer having a carboxylic acid, primary amine-grafted acrylic resins in which a primary amine is graft-polymerized onto an acrylic backbone, polyallylamine or its derivatives, and aminated phenols. Preferred anionic polymers include poly(meth)acrylic acid or its salts, or copolymers primarily composed of (meth)acrylic acid or its salts. The crosslinking agent is preferably at least one selected from the group consisting of a compound having a functional group selected from an isocyanate group, a glycidyl group, a carboxyl group, or an oxazoline group, and a silane coupling agent. The phosphoric acid or phosphoric acid salt is preferably a condensed phosphoric acid or a condensed phosphate salt.

[0107] An example of a corrosion-resistant coating is one formed by applying a solution in which fine particles of a metal oxide such as aluminum oxide, titanium oxide, cerium oxide, or tin oxide, or barium sulfate are dispersed in phosphoric acid to the surface of a barrier layer and then baking the coating at 150°C or higher.

[0108] The corrosion-resistant coating may have a laminated structure, if necessary, by further laminating at least one of a cationic polymer and an anionic polymer, such as those mentioned above.

[0109] The composition of the corrosion-resistant film can be analyzed by, for example, time-of-flight secondary ion mass spectrometry.

[0110] The amount of the corrosion-resistant film formed on the surface of the barrier layer 3 in the chemical conversion treatment is not particularly limited. For example, in the case of a coating type chromate treatment, the amount of the corrosion-resistant film formed on the surface of the barrier layer 3 is 2 It is desirable that the chromate compound is contained in an amount, calculated as chromium, of about 0.5 to 50 mg, preferably about 1.0 to 40 mg, the phosphorus compound in an amount, calculated as phosphorus, of about 0.5 to 50 mg, preferably about 1.0 to 40 mg, and the aminated phenol polymer in an amount, calculated as phosphorus, of about 1.0 to 200 mg, preferably about 5.0 to 150 mg, per 1000 ml of the aqueous solution.

[0111] The thickness of the corrosion-resistant coating is not particularly limited, but is preferably about 1 nm to 20 μm, more preferably about 1 nm to 100 nm, and even more preferably about 1 nm to 50 nm, from the viewpoint of the cohesive strength of the coating and the adhesive strength with the barrier layer and the thermally adhesive resin layer. The thickness of the corrosion-resistant coating can be measured by observation with a transmission electron microscope, or by a combination of observation with a transmission electron microscope and energy dispersive X-ray spectroscopy or electron energy loss spectroscopy. Analysis of the composition of the corrosion-resistant coating using time-of-flight secondary ion mass spectrometry can reveal, for example, the thickness of the corrosion-resistant coating consisting of secondary ions of Ce, P, and O (e.g., Ce2PO4 + , CePO4 - or at least one of ions of Cr, P, and O (e.g., CrPO2 + , CrPO4 - Peaks derived from at least one of the above are detected.

[0112] The chemical conversion treatment is carried out by applying a solution containing a compound used to form a corrosion-resistant coating to the surface of the barrier layer by bar coating, roll coating, gravure coating, immersion, or the like, and then heating the barrier layer to a temperature of about 70 to 200°C. Furthermore, before applying the chemical conversion treatment to the barrier layer, the barrier layer may be subjected to a degreasing treatment using an alkali immersion method, electrolytic cleaning, acid cleaning, electrolytic acid cleaning, or the like. By performing such a degreasing treatment, the chemical conversion treatment of the surface of the barrier layer can be carried out more efficiently. Furthermore, by using an acid degreasing agent prepared by dissolving a fluorine-containing compound in an inorganic acid for the degreasing treatment, it is possible to not only degrease the metal foil but also form a fluoride of the metal, which is in a passive state. In such cases, only the degreasing treatment may be carried out.

[0113] [Heat-fusible resin layer 4] In the exterior packaging material for an electricity storage device of the present disclosure, the heat-fusible resin layer 4 corresponds to the innermost layer and is a layer (sealant layer) that exhibits the function of sealing the electricity storage device elements by heat-fusible resin layers being heat-fused together when the electricity storage device is assembled.

[0114] The resin constituting the heat-sealable resin layer 4 is not particularly limited as long as it is heat-sealable, but resins containing a polyolefin skeleton, such as polyolefin and acid-modified polyolefin, are preferred. The presence of a polyolefin skeleton in the resin constituting the heat-sealable resin layer 4 can be determined by, for example, infrared spectroscopy, gas chromatography mass spectrometry, or the like. Furthermore, when the resin constituting the heat-sealable resin layer 4 is analyzed by infrared spectroscopy, a peak derived from maleic anhydride is preferably detected. For example, when maleic anhydride-modified polyolefin is measured by infrared spectroscopy, a peak derived from maleic anhydride is detected at a wavenumber of 1760 cm. -1 Nearby and wave number 1780 cm -1 A peak derived from maleic anhydride is detected around . When the thermally adhesive resin layer 4 is a layer made of maleic anhydride-modified polyolefin, a peak derived from maleic anhydride is detected by infrared spectroscopy. However, if the degree of acid modification is low, the peak becomes small and may not be detected. In such cases, analysis can be performed by nuclear magnetic resonance spectroscopy.

[0115] The heat-sealable resin layer 4 preferably contains a resin containing a polyolefin skeleton as a main component, more preferably a polyolefin as a main component, and even more preferably polypropylene as a main component. Here, "main component" refers to a resin component whose content of the resin components contained in the heat-sealable resin layer 4 is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more. For example, "the heat-sealable resin layer 4 contains polypropylene as a main component" means that the polypropylene content of the resin components contained in the heat-sealable resin layer 4 is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more.

[0116] Specific examples of polyolefins include polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; ethylene-α-olefin copolymers; polypropylenes such as homopolypropylene, block copolymers of polypropylene (e.g., block copolymers of propylene and ethylene), and random copolymers of polypropylene (e.g., random copolymers of propylene and ethylene); propylene-α-olefin copolymers; and ethylene-butene-propylene terpolymers. Among these, polypropylene is preferred. When the polyolefin resin is a copolymer, it may be a block copolymer or a random copolymer. These polyolefin resins may be used alone or in combination of two or more.

[0117] The polyolefin may also be a cyclic polyolefin. Cyclic polyolefins are copolymers of olefins and cyclic monomers, and examples of olefins constituting the cyclic polyolefins include ethylene, propylene, 4-methyl-1-pentene, styrene, butadiene, and isoprene. Examples of cyclic monomers constituting the cyclic polyolefins include cyclic alkenes such as norbornene; and cyclic dienes such as cyclopentadiene, dicyclopentadiene, cyclohexadiene, and norbornadiene. Among these, cyclic alkenes are preferred, and norbornene is more preferred.

[0118] The polyolefin may also be an acid-modified polyolefin. An acid-modified polyolefin is a polymer modified by block polymerization or graft polymerization of a polyolefin with an acid component. Examples of the acid-modified polyolefin include the above-mentioned polyolefins, copolymers of the above-mentioned polyolefins with polar molecules such as acrylic acid or methacrylic acid, and polymers such as crosslinked polyolefins. Examples of the acid component used for acid modification include carboxylic acids or anhydrides thereof, such as maleic acid, acrylic acid, itaconic acid, crotonic acid, maleic anhydride, and itaconic anhydride.

[0119] The acid-modified polyolefin may be an acid-modified cyclic polyolefin. The acid-modified cyclic polyolefin is a polymer obtained by copolymerizing a part of the monomers constituting the cyclic polyolefin by replacing it with an acid component, or by block polymerizing or graft polymerizing an acid component onto the cyclic polyolefin. The acid-modified cyclic polyolefin is the same as described above. The acid component used for the acid modification is the same as the acid component used for the modification of the polyolefin.

[0120] Preferred acid-modified polyolefins include polyolefins modified with carboxylic acid or its anhydride, polypropylenes modified with carboxylic acid or its anhydride, maleic anhydride-modified polyolefins, and maleic anhydride-modified polypropylenes.

[0121] The thermally adhesive resin layer 4 may be formed of one type of resin alone or a blend polymer of two or more types of resins. Furthermore, the thermally adhesive resin layer 4 may be formed of only one layer, or may be formed of two or more layers of the same or different resins.

[0122] When the thermally adhesive resin layer 4 is laminated with the barrier layer 3, the adhesive layer 5, or the like to produce the exterior packaging material 10 for an electricity storage device of the present disclosure, a pre-formed resin film may be used as the thermally adhesive resin layer 4. Alternatively, the thermally adhesive resin that forms the thermally adhesive resin layer 4 may be formed into a film on the surface of the barrier layer 3, the adhesive layer 5, or the like by extrusion molding, coating, or the like, to form the thermally adhesive resin layer 4 from a resin film.

[0123] Furthermore, the thermally adhesive resin layer 4 may contain a lubricant or the like, if necessary. When the thermally adhesive resin layer 4 contains a lubricant, the formability of the electrical storage device packaging material can be improved. The lubricant is not particularly limited, and known lubricants can be used.

[0124] The lubricant is not particularly limited, but preferably an amide-based lubricant is used. Specific examples of the lubricant include those exemplified for the base layer 1. The lubricant may be used alone or in combination of two or more types, and a combination of two or more types is preferred.

[0125] In the present disclosure, from the viewpoint of improving the formability of the exterior material for an electrical storage device, it is preferable that a lubricant be present on at least one of the surface and the interior of the heat-sealable resin layer 4. The lubricant is not particularly limited, but preferably an amide-based lubricant is used. Specific examples of amide-based lubricants include saturated fatty acid amides, unsaturated fatty acid amides, substituted amides, methylolamides, saturated fatty acid bisamides, unsaturated fatty acid bisamides, fatty acid ester amides, and aromatic bisamides. Specific examples of saturated fatty acid amides include lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, and hydroxystearic acid amide. Specific examples of unsaturated fatty acid amides include oleic acid amide and erucic acid amide. Specific examples of substituted amides include N-oleyl palmitic acid amide, N-stearyl stearic acid amide, N-stearyl oleic acid amide, N-oleyl stearic acid amide, and N-stearyl erucic acid amide. Specific examples of methylolamides include methylol stearic acid amide. Specific examples of saturated fatty acid bisamides include methylene bisstearic acid amide, ethylene biscapric acid amide, ethylene bislauric acid amide, ethylene bisstearic acid amide, ethylene bishydroxystearic acid amide, ethylene bisbehenic acid amide, hexamethylene bisstearic acid amide, hexamethylene bisbehenic acid amide, hexamethylene hydroxystearic acid amide, N,N'-distearyl adipamide, N,N'-distearyl sebacic acid amide, etc. Specific examples of unsaturated fatty acid bisamides include ethylene bisoleic acid amide, ethylene biserucic acid amide, hexamethylene bisoleic acid amide, N,N'-dioleyl adipamide, N,N'-dioleyl sebacic acid amide, etc. Specific examples of fatty acid ester amides include stearamidoethyl stearate, etc. Specific examples of aromatic bisamides include m-xylylene bisstearic acid amide, m-xylylene bishydroxystearic acid amide, and N,N'-distearylisophthalic acid amide.The lubricant may be used alone or in combination of two or more kinds, and it is preferable to use a combination of two or more kinds.

[0126] When a lubricant is present on the surface of the heat-sealable resin layer 4, the amount of the lubricant is not particularly limited. However, from the viewpoint of improving the formability of the exterior material for an electrical storage device, the amount of the lubricant is preferably about 1 mg / m 2 or more, more preferably about 3 mg / m 2 or more, more preferably about 5 mg / m 2 or more, more preferably about 10 mg / m 2 or more, more preferably about 15 mg / m 2 or more, and preferably about 50 mg / m 2 or less, more preferably about 40 mg / m 2 The preferred range is 1 to 50 mg / m 2 Degree, 1-40mg / m 2 Degree, 3-50mg / m 2 Degree, 3-40mg / m 2 degree, 5-50mg / m 2 degree, 5-40mg / m 2 degree, 10-50mg / m 2 degree, 10-40mg / m 2 degree, 15-50mg / m 2 degree, 15-40mg / m 2 The degree of

[0127] When a lubricant is present inside the heat-sealable resin layer 4, the amount thereof is not particularly limited, but from the viewpoint of improving the formability of the packaging material for an electrical storage device, it is preferably about 100 ppm or more, more preferably about 300 ppm or more, and even more preferably about 500 ppm or more, and is preferably about 3000 ppm or less, more preferably about 2000 ppm or less, and preferred ranges include about 100 to 3000 ppm, about 100 to 2000 ppm, about 300 to 3000 ppm, about 300 to 2000 ppm, about 500 to 3000 ppm, and about 500 to 2000 ppm. When two or more types of lubricant are present inside the heat-sealable resin layer 4, the above amount of lubricant is the total amount of lubricant. Furthermore, when two or more types of lubricants are present inside the heat-sealable resin layer 4, the amount of the first type of lubricant present is not particularly limited, but from the viewpoint of improving the formability of the exterior material for an electrical storage device, it is preferably about 100 ppm or more, more preferably about 300 ppm or more, even more preferably about 500 ppm or more, and is preferably about 3000 ppm or less, more preferably about 2000 ppm or less, and preferred ranges include about 100 to 3000 ppm, about 100 to 2000 ppm, about 300 to 3000 ppm, about 300 to 2000 ppm, about 500 to 3000 ppm, and about 500 to 2000 ppm. The amount of the second type of lubricant present is not particularly limited, but from the viewpoint of improving the formability of the exterior material for an electricity storage device, it is preferably about 50 ppm or more, more preferably about 100 ppm or more, and even more preferably about 200 ppm or more, and is preferably about 1500 ppm or less, more preferably about 1000 ppm or less, and preferred ranges include about 50 to 1500 ppm, about 50 to 1000 ppm, about 100 to 1500 ppm, about 100 to 1000 ppm, about 200 to 1500 ppm, and about 200 to 1000 ppm.

[0128] The lubricant present on the surface of the heat-sealable resin layer 4 may be a lubricant exuded from the resin constituting the heat-sealable resin layer 4, or a lubricant applied to the surface of the heat-sealable resin layer 4.

[0129] The thickness of the heat-sealable resin layer 4 is not particularly limited as long as it functions to heat-seal the heat-sealable resin layers to each other and seal the electricity storage device element, but may be, for example, about 100 μm or less, preferably about 85 μm or less, and more preferably about 15 to 85 μm. Note that, for example, when the thickness of the adhesive layer 5 described below is 10 μm or more, the thickness of the heat-sealable resin layer 4 is preferably about 85 μm or less, more preferably about 15 to 45 μm. For example, when the thickness of the adhesive layer 5 described below is less than 10 μm or when the adhesive layer 5 is not provided, the thickness of the heat-sealable resin layer 4 is preferably about 20 μm or more, more preferably about 35 to 85 μm.

[0130] [Adhesive Layer 5] In the packaging material for an electricity storage device according to the present disclosure, the adhesive layer 5 is a layer that is provided as needed between the barrier layer 3 (or the corrosion-resistant coating) and the heat-sealable resin layer 4 in order to firmly bond them together.

[0131] The adhesive layer 5 is formed of a resin capable of bonding the barrier layer 3 and the heat-sealable resin layer 4. As the resin used to form the adhesive layer 5, for example, the same adhesive as exemplified for the adhesive layer 2 can be used.

[0132] Furthermore, from the viewpoint of firmly bonding the adhesive layer 5 and the heat-sealable resin layer 4, the resin used to form the adhesive layer 5 preferably contains a polyolefin skeleton, and examples thereof include the polyolefins, acid-modified polyolefins, cyclic polyolefins, and acid-modified cyclic polyolefins exemplified for the heat-sealable resin layer 4 described above. On the other hand, from the viewpoint of firmly bonding the barrier layer 3 and the adhesive layer 5, the adhesive layer 5 preferably contains an acid-modified polyolefin. Examples of acid-modified components include dicarboxylic acids such as maleic acid, itaconic acid, succinic acid, and adipic acid, as well as anhydrides thereof, acrylic acid, and methacrylic acid. However, from the viewpoint of ease of modification and versatility, maleic anhydride is most preferred. From the viewpoint of the heat resistance of the electrical storage device exterior material, the olefin component is preferably a polypropylene-based resin, and the adhesive layer 5 most preferably contains maleic anhydride-modified polypropylene.

[0133] When the resin used to form the adhesive layer 5 contains a polyolefin skeleton, the adhesive layer 5 preferably contains a resin containing a polyolefin skeleton as a main component, more preferably an acid-modified polyolefin as a main component, and even more preferably an acid-modified polypropylene as a main component. Here, "main component" means that the content of the resin component contained in the adhesive layer 5 is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more. For example, when the adhesive layer 5 contains acid-modified polypropylene as a main component, it means that the content of acid-modified polypropylene among the resin components contained in the adhesive layer 5 is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more.

[0134] The presence of a polyolefin skeleton in the resin constituting the adhesive layer 5 can be determined by, for example, infrared spectroscopy, gas chromatography mass spectrometry, or the like, and the analysis method is not particularly limited. Furthermore, the presence of an acid-modified polyolefin in the resin constituting the adhesive layer 5 can be determined by, for example, measuring a maleic anhydride-modified polyolefin by infrared spectroscopy, and finding a wave number of 1760 cm -1 Nearby and wave number 1780 cm -1 A peak derived from maleic anhydride is detected around this point. However, if the degree of acid modification is low, the peak may be small and not be detected. In this case, analysis can be performed using nuclear magnetic resonance spectroscopy.

[0135] Furthermore, from the viewpoint of ensuring durability such as heat resistance and resistance to contents of the electrical storage device packaging material, and of ensuring moldability while reducing the thickness, the adhesive layer 5 is more preferably a cured product of a resin composition containing an acid-modified polyolefin and a curing agent. Preferred examples of the acid-modified polyolefin include those described above.

[0136] The adhesive layer 5 is preferably a cured product of a resin composition containing an acid-modified polyolefin and at least one selected from the group consisting of a compound having an isocyanate group, a compound having an oxazoline group, and a compound having an epoxy group. A cured product of a resin composition containing an acid-modified polyolefin and at least one selected from the group consisting of a compound having an isocyanate group and a compound having an epoxy group is particularly preferred. The adhesive layer 5 preferably contains at least one selected from the group consisting of polyurethane, polyester, and epoxy resin, and more preferably contains polyurethane and epoxy resin. Examples of polyesters include ester resins formed by the reaction of epoxy groups with maleic anhydride groups, and amide ester resins formed by the reaction of oxazoline groups with maleic anhydride groups. If unreacted curing agents such as compounds having an isocyanate group, compounds having an oxazoline group, or epoxy resins remain in the adhesive layer 5, the presence of the unreacted materials can be confirmed by a method selected from the group consisting of infrared spectroscopy, Raman spectroscopy, time-of-flight secondary ion mass spectrometry (TOF-SIMS), and the like.

[0137] Furthermore, from the viewpoint of further enhancing the adhesion between the barrier layer 3 and the adhesive layer 5, the adhesive layer 5 is preferably a cured product of a resin composition containing a curing agent having at least one selected from the group consisting of an oxygen atom, a heterocycle, a C═N bond, and a C—O—C bond. Examples of curing agents having a heterocycle include curing agents having an oxazoline group and curing agents having an epoxy group. Examples of curing agents having a C═N bond include curing agents having an oxazoline group and curing agents having an isocyanate group. Examples of curing agents having a C—O—C bond include curing agents having an oxazoline group and curing agents having an epoxy group. Whether the adhesive layer 5 is a cured product of a resin composition containing such a curing agent can be confirmed by, for example, gas chromatography mass spectrometry (GCMS), infrared spectroscopy (IR), time-of-flight secondary ion mass spectrometry (TOF-SIMS), X-ray photoelectron spectroscopy (XPS), or other methods.

[0138] The compound having an isocyanate group is not particularly limited, but from the viewpoint of effectively increasing the adhesion between the barrier layer 3 and the adhesive layer 5, a polyfunctional isocyanate compound is preferably used. The polyfunctional isocyanate compound is not particularly limited as long as it is a compound having two or more isocyanate groups. Specific examples of polyfunctional isocyanate curing agents include pentane diisocyanate (PDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymers or nurates thereof, mixtures of these, and copolymers with other polymers. Other examples include adducts, biurets, and isocyanurates.

[0139] The content of the compound having an isocyanate group in the adhesive layer 5 is preferably in the range of 0.1 to 50 mass %, and more preferably in the range of 0.5 to 40 mass %, of the resin composition constituting the adhesive layer 5. This makes it possible to effectively improve the adhesion between the barrier layer 3 and the adhesive layer 5.

[0140] The compound having an oxazoline group is not particularly limited as long as it is a compound having an oxazoline skeleton. Specific examples of the compound having an oxazoline group include those having a polystyrene main chain and those having an acrylic main chain. Examples of commercially available products include the Epocross series manufactured by Nippon Shokubai Co., Ltd.

[0141] The proportion of the compound having an oxazoline group in the adhesive layer 5 is preferably in the range of 0.1 to 50 mass %, and more preferably in the range of 0.5 to 40 mass %, in the resin composition constituting the adhesive layer 5. This makes it possible to effectively improve the adhesion between the barrier layer 3 and the adhesive layer 5.

[0142] Examples of compounds having epoxy groups include epoxy resins. The epoxy resin is not particularly limited as long as it is a resin capable of forming a crosslinked structure by the epoxy groups present in the molecule, and known epoxy resins can be used. The weight-average molecular weight of the epoxy resin is preferably about 50 to 2,000, more preferably about 100 to 1,000, and even more preferably about 200 to 800. In the present disclosure, the weight-average molecular weight of the epoxy resin is a value measured by gel permeation chromatography (GPC) under conditions using polystyrene as a standard sample.

[0143] Specific examples of epoxy resins include glycidyl ether derivatives of trimethylolpropane, bisphenol A diglycidyl ether, modified bisphenol A diglycidyl ether, bisphenol F glycidyl ether, novolac glycidyl ether, glycerin polyglycidyl ether, polyglycerin polyglycidyl ether, etc. The epoxy resins may be used alone or in combination of two or more.

[0144] The proportion of the epoxy resin in the adhesive layer 5 is preferably in the range of 0.1 to 50 mass %, and more preferably in the range of 0.5 to 40 mass %, of the resin composition constituting the adhesive layer 5. This makes it possible to effectively improve the adhesion between the barrier layer 3 and the adhesive layer 5.

[0145] The polyurethane is not particularly limited, and any known polyurethane can be used. The adhesive layer 5 may be, for example, a cured product of two-component curing polyurethane.

[0146] The proportion of polyurethane in the adhesive layer 5 is preferably in the range of 0.1 to 50 mass %, and more preferably in the range of 0.5 to 40 mass %, of the resin composition constituting the adhesive layer 5. This makes it possible to effectively improve the adhesion between the barrier layer 3 and the adhesive layer 5 in an atmosphere containing a component that induces corrosion of the barrier layer, such as an electrolyte solution.

[0147] In addition, when the adhesive layer 5 is a cured product of a resin composition containing at least one selected from the group consisting of a compound having an isocyanate group, a compound having an oxazoline group, and an epoxy resin, and the acid-modified polyolefin, the acid-modified polyolefin functions as the main agent, and the compound having an isocyanate group, the compound having an oxazoline group, and the compound having an epoxy group each function as a curing agent.

[0148] The adhesive layer 5 may contain a modifier having a carbodiimide group.

[0149] When the adhesive layer 5 is laminated with the barrier layer 3, the heat-sealable resin layer 4, or the like to produce the packaging material for an electricity storage device 10 of the present disclosure, a pre-formed resin film may be used as the adhesive layer 5. Alternatively, the heat-sealable resin that forms the adhesive layer 5 may be formed into a film on the surface of the barrier layer 3, the heat-sealable resin layer 4, or the like by extrusion molding, coating, or the like, to form the adhesive layer 5 from a resin film.

[0150] The thickness of the adhesive layer 5 is preferably about 50 μm or less, about 40 μm or less, about 30 μm or less, about 20 μm or less, or about 5 μm or less. The thickness of the adhesive layer 5 is preferably about 0.1 μm or more, or about 0.5 μm or more. The thickness of the adhesive layer 5 is preferably about 0.1 to 50 μm, about 0.1 to 40 μm, about 0.1 to 30 μm, about 0.1 to 20 μm, about 0.1 to 5 μm, about 0.5 to 50 μm, about 0.5 to 40 μm, about 0.5 to 30 μm, about 0.5 to 20 μm, or about 0.5 to 5 μm. More specifically, in the case of adhesives such as those exemplified for the adhesive layer 2 or a cured product of an acid-modified polyolefin and a curing agent, the thickness is preferably about 1 to 10 μm, more preferably about 1 to 5 μm. Furthermore, when a resin exemplified for the heat-fusible resin layer 4 is used, the thickness is preferably about 2 to 50 μm, more preferably about 10 to 40 μm. When the adhesive layer 5 is an adhesive exemplified for the adhesive layer 2 or a cured product of a resin composition containing an acid-modified polyolefin and a curing agent, the adhesive layer 5 can be formed, for example, by applying the resin composition and curing it by heating or the like. When a resin exemplified for the heat-fusible resin layer 4 is used, the heat-fusible resin layer 4 and the adhesive layer 5 can be formed, for example, by extrusion molding.

[0151] 3. Manufacturing Method of Exterior Material for Electricity Storage Device The manufacturing method of the exterior material for an electricity storage device is not particularly limited as long as a laminate is obtained in which the layers included in the exterior material for an electricity storage device of the present disclosure are laminated, and an example is a method including a step of laminating at least the surface coating layer 6, the base material layer 1, the barrier layer 3, and the heat-sealable resin layer 4 in this order. As described above, in the exterior material for an electricity storage device of the present disclosure, a colorant is contained in at least one layer outside the barrier layer.

[0152] An example of a manufacturing method for an exterior material for an electricity storage device according to the present disclosure is as follows. First, a laminate (hereinafter, sometimes referred to as "laminate A") is formed in which a base layer 1, an adhesive layer 2, and a barrier layer 3 are laminated in this order. Specifically, the laminate A can be formed by a dry lamination method in which an adhesive used to form the adhesive layer 2 is applied to the base layer 1 or to the barrier layer 3, the surface of which has been chemically treated as necessary, by a coating method such as gravure coating or roll coating, and then dried, and the barrier layer 3 or the base layer 1 is laminated thereon, and the adhesive layer 2 is cured.

[0153] Next, a heat-sealable resin layer 4 is laminated on the barrier layer 3 of the laminate A. When the heat-sealable resin layer 4 is laminated directly on the barrier layer 3, the heat-sealable resin layer 4 may be laminated on the barrier layer 3 of the laminate A by a method such as thermal lamination or extrusion lamination. When an adhesive layer 5 is provided between the barrier layer 3 and the heat-sealable resin layer 4, the adhesive layer 5 and the heat-sealable resin layer 4 may be laminated by, for example, (1) extrusion lamination, (2) thermal lamination, (3) sandwich lamination, or (4) dry lamination. Examples of the (1) extrusion lamination method include a method of laminating the adhesive layer 5 and the heat-sealable resin layer 4 on the barrier layer 3 of the laminate A by extrusion (co-extrusion lamination, tandem lamination), etc. Examples of the (2) thermal lamination method include a method of separately forming a laminate in which an adhesive layer 5 and a heat-fusible resin layer 4 are laminated, and laminating this on the barrier layer 3 of the laminate A, or a method of forming a laminate in which an adhesive layer 5 is laminated on the barrier layer 3 of the laminate A, and laminating this on the heat-fusible resin layer 4. Examples of the (3) sandwich lamination method include a method of pouring a molten adhesive layer 5 between the barrier layer 3 of the laminate A and the heat-fusible resin layer 4 that has been previously formed into a sheet, and bonding the laminate A and the heat-fusible resin layer 4 together via the adhesive layer 5. Examples of the (4) dry lamination method include a method of solution-coating an adhesive for forming the adhesive layer 5 on the barrier layer 3 of the laminate A, drying the adhesive, or baking the adhesive, and laminating the heat-fusible resin layer 4 that has been previously formed into a sheet on the adhesive layer 5.

[0154] A surface coating layer 6 is laminated on the surface of the base layer 1 opposite to the barrier layer 3. The surface coating layer 6 can be formed, for example, by applying the above-mentioned resin for forming the surface coating layer 6 to the surface of the base layer 1. The order of the step of laminating the barrier layer 3 on the surface of the base layer 1 and the step of laminating the surface coating layer 6 on the surface of the base layer 1 is not particularly limited. For example, after forming the surface coating layer 6 on the surface of the base layer 1, the barrier layer 3 may be formed on the surface of the base layer 1 opposite to the surface coating layer 6.

[0155] As described above, a laminate is formed which includes the surface coating layer 6, the base material layer 1, the optional adhesive layer 2, the barrier layer 3, the optional adhesive layer 5, and the heat-fusible resin layer 4 in this order. In order to strengthen the adhesion of the optional adhesive layer 2 and the optional adhesive layer 5, the laminate may be further subjected to a heat treatment.

[0156] In the packaging material for an electricity storage device, each layer constituting the laminate may be subjected to a surface activation treatment such as corona treatment, blast treatment, oxidation treatment, ozone treatment, etc. as necessary to improve processability. For example, by subjecting the surface of the base layer 1 opposite to the barrier layer 3 to corona treatment, the printability of ink on the surface of the base layer 1 can be improved.

[0157] 4. Uses of the Electricity Storage Device Exterior Material The electricity storage device exterior material of the present disclosure is used in a package for hermetically housing electricity storage device elements such as a positive electrode, a negative electrode, and an electrolyte. That is, an electricity storage device can be formed by housing an electricity storage device element including at least a positive electrode, a negative electrode, and an electrolyte in a package formed from the electricity storage device exterior material of the present disclosure. In other words, an electricity storage device can be formed by wrapping an electricity storage device element in the electricity storage device exterior material of the present disclosure.

[0158] Specifically, an electricity storage device using the electricity storage device packaging material is provided by covering an electricity storage device element including at least a positive electrode, a negative electrode, and an electrolyte with the electricity storage device packaging material of the present disclosure in a state in which metal terminals connected to each of the positive electrode and the negative electrode protrude outward, so that a flange portion (a region where the heat-sealable resin layers contact each other) can be formed around the periphery of the electricity storage device element, and then heat-sealing the heat-sealable resin layers of the flange portion to form a hermetic seal. Note that when an electricity storage device element is housed in a package formed from the electricity storage device packaging material of the present disclosure, the package is formed so that the heat-sealable resin portion of the electricity storage device packaging material of the present disclosure faces inside (the surface that contacts the electricity storage device element). A package may be formed by overlapping two electrical storage device exterior materials with the heat-sealable resin layers facing each other and heat-sealing the peripheral edges of the overlapped electrical storage device exterior materials, or by folding one electrical storage device exterior material over and overlapping it, and heat-sealing the peripheral edges, as in the example shown in Fig. 4. When the materials are folded over and overlapped, the package may be formed by heat-sealing the sides other than the folded side to form a three-sided seal, as in the example shown in Fig. 4, or by folding over so as to form a flange and sealing all four sides. Note that when the innermost and outermost layers of the electrical storage device exterior material are heat-sealable resin layers, the package may be formed by heat-sealing the heat-sealable resin layer of the innermost layer and the heat-sealable resin layer of the outermost layer.

[0159] The electricity storage device element may be sealed with a lid in addition to the electricity storage device exterior material. That is, the electricity storage device exterior material and the lid constitute an exterior (an exterior for an electricity storage device) that seals the electricity storage device element. For example, the electricity storage device element may be housed inside a cylindrically configured electricity storage device exterior material, and the opening may be closed with the lid. In another example, the electricity storage device element connected to the lid may be housed inside a cylindrically configured electricity storage device exterior material that has an opening, and the opening may be closed with the lid. The lid and the electricity storage device exterior material are preferably joined by any means. From the viewpoint of reducing dead space between the electricity storage device element and the electricity storage device exterior material to improve the volumetric energy density of the electricity storage device, the electricity storage device exterior material is preferably wrapped around the electricity storage device element and the lid.

[0160] The lid body can be formed, for example, from a resin molded product, a metal molded product, an exterior material for an electricity storage device, or a combination thereof. In this disclosure, when the lid body is referred to as a resin molded product, this does not include an embodiment in which the lid body is formed solely from a film defined by JIS K6900-1994 [Plastics - Terminology]. When the lid body is a metal molded product, the lid body also functions as a metal terminal, so the metal terminal can be omitted. The lid body may be formed from a resin material and a conductive material.

[0161] Furthermore, a recess for accommodating an electricity storage device element may be formed in the electrical storage device packaging material by deep drawing or bulging molding. As shown in the example in Fig. 4, a recess may be provided in one electrical storage device packaging material and no recess may be provided in the other electrical storage device packaging material, or a recess may also be provided in the other electrical storage device packaging material.

[0162] The exterior material for an electricity storage device of the present disclosure can be suitably used in an electricity storage device such as a battery (including a condenser, a capacitor, etc.). The exterior material for an electricity storage device of the present disclosure may be used in either a primary battery or a secondary battery, but is preferably used in a secondary battery. The type of secondary battery to which the exterior material for an electricity storage device of the present disclosure is applied is not particularly limited, and examples include lithium ion batteries, lithium ion polymer batteries, all-solid-state batteries, semi-solid batteries, quasi-solid batteries, polymer batteries, all-resin batteries, lead-acid batteries, nickel-metal hydride batteries, nickel-cadmium batteries, nickel-iron batteries, nickel-zinc batteries, silver oxide-zinc batteries, metal-air batteries, polyvalent cation batteries, condensers, and capacitors. Among these secondary batteries, lithium ion batteries and lithium ion polymer batteries are suitable applications for the exterior material for an electricity storage device of the present disclosure.

[0163] The present disclosure will be described in detail below with reference to examples and comparative examples, but the present disclosure is not limited to the examples.

[0164] <Production of an Exterior Material for an Electricity Storage Device> Example 1-15 An oriented nylon (ONy) film (thickness: 15 μm) was prepared as the base layer. Furthermore, aluminum foil (JIS H4160:1994 A8021H-O (thickness: 35 μm)) was prepared as the barrier layer. Next, an adhesive (two-component urethane adhesive) described below was applied to one side of the aluminum foil (ALM), and an adhesive layer (thickness: 3 μm) was formed on the barrier layer. As shown in Table 1, in each example, a white adhesive layer containing a white pigment, a black adhesive layer containing a black pigment, and an uncolored adhesive layer (colorless and transparent) containing no colorant were prepared. The white pigment was titanium oxide, and the black pigment was carbon black.

[0165] Next, the adhesive layer on the barrier layer and the substrate layer were laminated by dry lamination, and then aging treatment was performed to produce a substrate layer / adhesive layer / barrier layer laminate. Both sides of the aluminum foil were subjected to chemical conversion treatment. The chemical conversion treatment of the aluminum foil was performed by applying a treatment solution consisting of a phenolic resin, a chromium fluoride compound, and phosphoric acid to the aluminum foil in an amount of 10 mg / m2. 2(dry mass) was applied to both sides of an aluminum foil by roll coating, and baked.

[0166] Next, maleic anhydride-modified polypropylene (PPa) as an adhesive layer (thickness: 20 μm) and random polypropylene (PP) as a heat-sealable resin layer (thickness: 15 μm) were co-extruded onto the barrier layer of each of the laminates obtained above, thereby laminating the adhesive layer / heat-sealable resin layer onto the barrier layer.

[0167] Furthermore, a surface coating layer was formed by coating the surface of the substrate layer of the resulting laminate with a resin composition for forming the surface coating layer (the resin was a polyurethane resin formed from a mixture of a polyol compound and an isocyanate compound) to a thickness of 3 μm in Examples 1 to 4 and 8 to 10, 4 μm in Examples 5 to 7, 5 μm in Examples 11 to 14, and 6 μm in Example 15. As shown in Table 1, in each Example, the resin composition for forming the surface coating layer was blended with a matting agent, a surface coating layer blended with a white pigment, a white surface coating layer blended with a white pigment and a matting agent, a surface coating layer blended with yellow and red pigments as colorants, a white pigment and a matting agent, and an uncolored surface coating layer (colorless and transparent) that did not blend a colorant or a matting agent into the resin composition. The matting agent was silica, and the white pigment was titanium oxide.

[0168] In the column for "surface coating layer" in Table 1, Examples 5 to 7, 11 to 13, and 15 represent a two-layer structure in which the surface coating layer is divided into two stages. Examples 5 to 7 have a two-layer structure in which, from the outside, an uncolored surface coating layer and a surface coating layer containing a white pigment are laminated. Examples 11 to 13 have a two-layer structure in which, from the outside, a surface coating layer containing a matting agent and a surface coating layer containing a white pigment are laminated. Example 15 has a two-layer structure in which, from the outside, a surface coating layer containing yellow and red pigments and a matting agent and a surface coating layer containing a white pigment and a matting agent are laminated. In Examples 5 to 7, the resin composition was applied twice, each with a thickness of 2.0 μm, to achieve a total surface coating layer thickness of 4 μm. In Examples 11 to 13, the resin composition was applied twice, each with a thickness of 2.5 μm, to achieve a total surface coating layer thickness of 5 μm. In Example 15, the resin composition was applied twice to a thickness of 3 μm each, so that the total thickness of the surface coating layer was 6 μm.

[0169] Through the above steps, a laminate (total thickness of 91 μm in Examples 1 to 4 and 8 to 10, 92 μm in Examples 5 to 7, 93 μm in Examples 11 to 14, and 94 μm in Example 15) in which the surface coating layer (3 μm in Examples 5 to 7, 4 μm in Examples 11 to 14, and 6 μm in Example 15) / substrate layer (thickness 15 μm) / adhesive layer (3 μm) / barrier layer (35 μm) / adhesive layer (20 μm) / thermally adhesive resin layer (15 μm) was laminated in this order from the outside in was obtained.

[0170] <Glass Transition Temperature (Tg) of Surface Coating Layer> Using a rigid pendulum-type physical property tester, the glass transition temperature Tg (°C) of the surface coating layer of the exterior material for an electricity storage device obtained in each example was measured under the following measurement conditions. The results are shown in Table 1. (Measurement Conditions) Measurement Device: Rigid Pendulum-Type Physical Property Tester (RPT-3000W) manufactured by A&D Co., Ltd. Frame Used: FRB-400 / Disc Weight, Third from the Bottom Edge Used: RBP-040 Pretreatment: The AL plate immersed in an acetone solution is subjected to ultrasonic cleaning (5 minutes). The edge is also subjected to ultrasonic cleaning for 5 minutes or more. Temperature Profile: The temperature is raised from room temperature of 25°C to 250°C at a constant temperature over 5 minutes. The aluminum plate and measurement sample are fixed to the heat stage using Kapton tape.

[0171] <Elastic modulus EIT of the surface coating layer (N / mm 2 )> Using a microhardness tester (Picodentor), the elastic modulus EIT (N / mm 2 ) was measured. The results are shown in Table 1. In a measurement environment at 25°C, a diamond square pyramid-shaped Vickers indenter with a facing angle of 136° was pressed into the surface of the surface coating layer from the perpendicular direction, and the elastic modulus EIT was calculated from the obtained load-displacement curve. The average value obtained from 48 measurement positions (including recesses, protrusions, resin parts, and filler parts) on the surface coating layer was used as the elastic modulus EIT of the surface coating layer. (Measurement conditions) Measurement device: Picodentor HM-500 manufactured by Fischer Instruments Indenter: PICO012 (Vickers) Pretreatment: With the surface coating layer facing up, the exterior material for an electricity storage device was fixed on a slide glass with an adhesive, and the slide glass was fixed to the measurement stage with tape. Load control: Maximum 0.1 mN Measurement profile: Load for 10 seconds, hold for 5 seconds, unload for 10 seconds

[0172] <Erosion Rate of Surface Coating Layer> The erosion rate of the surface coating layer of the electrical storage device exterior material obtained in each example was measured by an MSE (micro slurry jet erosion) test under the following measurement conditions. The results are shown in Table 1. (Measurement Conditions) Measurement equipment: Model MSE-A (MSE test equipment) manufactured by Palmeso Co., Ltd. Pretreatment: With the surface coating layer facing up, the electrical storage device exterior material was fixed onto a stainless steel plate with double-sided tape, and the stainless steel plate was fixed to the measurement stage. Particles: Polygonal alumina 0.3 μm (MSE-GA-0.3-1 and PGA-0.3-10-00) Slurry projection amount: 2.0 g / time (6.0 g / time for Sample 1 only) Number of slurry projections: 3 to 15 times Projection force: 1 / 10 projection force

[0173] <Appearance Evaluation of Electricity Storage Device Exterior Materials> The exterior materials for electricity storage devices obtained in each example were observed with the naked eye from a distance of 30 cm under fluorescent light to confirm their color. The results are shown in Table 1. <Evaluation Method> - Location of sample for appearance evaluation: A flat portion of the exterior material for electricity storage devices with no creases or dents on the surface was selected. - Sample size: The above-mentioned sample location was cut out to 10 cm x 10 cm. - Location of sample placement: The sample was placed on a flat desk under fluorescent light. - Sample orientation: The liquid application direction was the vertical direction, and the sample was placed vertically. - Evaluator's position relative to the sample: Stand in front of the vertically oriented sample. - Distance between sample and naked eye: 30 cm. - Visual observation: The sample was observed with the naked eye at an angle of 60° from the desk surface.

[0174] <Evaluation of Appearance of Electricity Storage Device Exterior Material After Heat Sealing> The electricity storage device exterior material obtained in each example was cut into a size of 60 mm (TD) x 120 mm (MD) to prepare a sample. Next, the sample was folded in half in the MD direction so that the heat-sealable resin layers of the sample faced each other. Next, the upper and lower surfaces of the sample were sandwiched between 7 mm-wide seal heads of a heat sealer (the seal heads on the upper and lower surfaces were in contact with the surface coating layer) so as to heat-seal the heat-sealable resin layers of the folded electricity storage device exterior material. The heat-sealed condition was a temperature of 210 ° C., a pressure of 1.5 MPa, and a time of 3 seconds. The gloss (gloss value) of the surface coating layer at the heat-sealed position was measured at a measurement angle of 60 ° using a gloss meter (manufacturer: BYK, product name: Gardner Micro Trigloss). The gloss (gloss value) of the surface coating layer at the non-heat-sealed position was also measured. The gloss level was measured in accordance with JIS Z 8741:1997 using a commercially available gloss level meter (Micro Trigloss AG-4430 manufactured by BYK-Gardner) under the condition that the angle of incidence of light on the surface to be measured was 60°, and the observed Gu value was taken as the gloss level. The average value of measurements (n=3) was used as the gloss level (gloss value). The absolute value ΔGU of the difference between the gloss level of the surface coating layer at the position where the sample was heat-sealed and the gloss level of the surface coating layer at the position where the sample was not heat-sealed was calculated, and the appearance of the exterior material for an electricity storage device after heat sealing was evaluated according to the following evaluation criteria. The results are shown in Table 1. (Evaluation criteria) A: ΔGU is 0.3 or less B: ΔGU is more than 0.3 and 0.8 or less C: ΔGU is more than 0.8

[0175] <Evaluation of Scratch Resistance of Electricity Storage Device Exterior Material (Steel Wool Resistance)> The heat-fusible resin layer side of the electricity storage device exterior material obtained in each example was brought into contact with a glass plate and fixed with tape. Next, a circular piece of steel wool with a diameter of 4 cm and a weight (200 g) were layered, in that order, on the surface coating layer of the fixed electricity storage device exterior material. With the weight load applied, the surface coating layer was rubbed with steel wool (product name: Bonstar Roll Pad B-061, manufactured by Japan Steel Wool Co., Ltd. (sold by Bonstar Sales Co., Ltd.)). The speed when rubbing the surface coating layer with the steel wool was a constant 300 mm / min, and the distance of one round trip was 150 mm. The direction in which the surface coating layer was rubbed with the steel wool was the MD (machine direction) of the electricity storage device exterior material, and the measurement direction of the gloss (gloss value) was also the MD (machine direction) of the electricity storage device exterior material. The gloss (gloss value) at a measurement angle of 60° was measured using a gloss meter (manufacturer: BYK, product name: Gardner Micro Trigloss) for the surface coating layer at a position where the surface coating layer was rubbed with steel wool. The gloss (gloss value) was also measured for the surface coating layer at a position where the surface coating layer was not rubbed with steel wool. The gloss measurement was performed in accordance with JIS Z 8741:1997 using a commercially available gloss meter (BYK-Gardner Micro Trigloss AG-4430) under the condition of an incident angle of light to the surface to be measured of 60°, and the observed Gu value was taken as the gloss. The average value of the number of measurements n = 3 was adopted as the gloss (gloss value). The absolute value ΔGU of the difference between the gloss of the surface coating layer at a position where the surface coating layer was rubbed with steel wool and the gloss of the surface coating layer at a position where the surface coating layer was not rubbed with steel wool was calculated, and the scratch resistance of the exterior material for an electricity storage device was evaluated according to the following evaluation criteria. The results are shown in Table 1. (Evaluation criteria) A: ΔGU is 1.5 or less B: ΔGU is more than 1.5 and 3.0 or less C: ΔGU is more than 3.0

[0176]

[0177] As is clear from the results shown in Table 1, the exterior materials for electricity storage devices of Examples 1 to 15 can be colored in consideration of the color of the housing of the product to which the electricity storage device is attached by incorporating a colorant into the surface coating layer and adhesive layer located outside the barrier layer. More specifically, the appearance of the exterior material for electricity storage devices can be colored in various ways depending on the presence or absence of a colorant in the surface coating layer and adhesive layer, the color, type, and content of the colorant, and even the presence or absence of a matting agent, making it possible to adjust the color according to the color of the product's housing. As described above, with conventional exterior materials for electricity storage devices, the appearance of the exterior material for electricity storage devices is not adjusted in advance in consideration of the color of the housing of the product to which the electricity storage device is attached. However, the exterior material for electricity storage devices of the present disclosure makes such adjustment possible, thereby further improving the design of the product to which the electricity storage device is attached.

[0178] As described above, the present disclosure provides the following aspects of the invention. Item 1. An electrical storage device packaging material comprising a laminate including, in order from the outside, at least a surface coating layer, a base material layer, a barrier layer, and a heat-sealable resin layer, wherein a colorant is contained in at least one layer outer than the barrier layer. Item 2. The electrical storage device packaging material according to Item 1, further including an adhesive layer between the base material layer and the barrier layer. Item 3. The electrical storage device packaging material according to Item 2, wherein the adhesive layer contains the colorant. Item 4. The electrical storage device packaging material according to any one of Items 1 to 3, wherein the surface coating layer contains the colorant. Item 5. The electrical storage device packaging material according to any one of Items 1 to 4, wherein the surface coating layer contains a matting agent. Item 6. The electrical storage device packaging material according to any one of Items 1 to 5, wherein the electrical storage device has a white appearance. Item 7. The electrical storage device packaging material according to any one of Items 1 to 6, further including an adhesive layer between the barrier layer and the heat-sealable resin layer. Item 8. Item 9. The exterior material for an electrical storage device according to any one of Items 1 to 7, wherein the surface coating layer has a glass transition temperature (Tg) of 120° C. or higher as measured by a rigid pendulum physical property tester. Item 10. The surface coating layer has an elastic modulus EIT of 2.0 N / mm 2Item 10. The electrical storage device packaging material according to any one of Items 1 to 9, wherein the erosion rate of the surface coating layer, measured under the following measurement conditions, is 0.15 μm / g or less. (Measurement conditions) Measurement equipment: Commercially available MSE test equipment Pretreatment: With the surface coating layer facing up, the electrical storage device packaging material is fixed onto a stainless steel plate with double-sided tape, and the stainless steel plate is fixed to a measurement stage. Particles: Polygonal alumina 0.3 μm (MSE-GA-0.3-1 and PGA-0.3-10-00) Slurry injection amount: 2.0 g / time (6.0 g / time for Sample 1 only) Slurry injection count: 3 to 15 times Projection force: 1 / 10 projection force Item 11. Item 11. A method for producing an electrical storage device packaging material, comprising a step of obtaining a laminate in which, from the outside, at least a surface coating layer, a base material layer, a barrier layer, and a heat-sealable resin layer are laminated, wherein a colorant is contained in at least one layer outer than the barrier layer. Item 12. An electrical storage device, in which an electrical storage device element including at least a positive electrode, a negative electrode, and an electrolyte is housed in a package formed from the electrical storage device packaging material according to any one of Items 1 to 10.

[0179] REFERENCE SIGNS LIST 1 base material layer 2 adhesive layer 3 barrier layer 4 heat-sealable resin layer 5 adhesive layer 6 surface coating layer 10 packaging material for electricity storage device

Claims

1. An exterior material for an electricity storage device, which is composed of a laminate having, in order from the outside, at least a surface coating layer, a base material layer, a barrier layer, and a heat-sealable resin layer, and at least one layer outside the barrier layer contains a colorant.

2. The exterior packaging material for an electricity storage device according to claim 1, further comprising an adhesive layer between the base layer and the barrier layer.

3. The packaging material for an electricity storage device according to claim 2, wherein the adhesive layer contains the colorant.

4. The exterior packaging material for an electricity storage device according to any one of claims 1 to 3, wherein the surface coating layer contains the colorant.

5. The exterior material for an electricity storage device according to any one of claims 1 to 3, wherein the surface coating layer contains a matting agent.

6. The exterior material for an electricity storage device according to any one of claims 1 to 3, which has a white appearance.

7. The packaging material for an electricity storage device according to any one of claims 1 to 3, further comprising an adhesive layer between the barrier layer and the heat-sealable resin layer.

8. The exterior material for an electricity storage device according to any one of claims 1 to 3, wherein the glass transition temperature (Tg) of the surface coating layer, measured by a rigid pendulum type physical property tester, is 120°C or higher.

9. The elastic modulus EIT of the surface coating layer measured by a microhardness tester is 2.0 N / mm 2 The electrical storage device exterior material according to any one of claims 1 to 3.

10. The exterior material for an electricity storage device according to any one of claims 1 to 3, wherein the erosion rate of the surface coating layer measured under the following measurement conditions is 0.15 μm / g or less. (Measurement conditions) Measurement equipment: Commercially available MSE test equipment Pretreatment: With the surface coating layer facing up, the exterior material for an electricity storage device is fixed onto a stainless steel plate with double-sided tape, and the stainless steel plate is fixed to the measurement stage. Particles: Polygonal alumina 0.3 μm (MSE-GA-0.3-1 and PGA-0.3-10-00) Slurry projection amount: 2.0 g / time (6.0 g / time only for Sample 1) Number of times slurry is projected: 3 to 15 times Projection force: 1 / 10 projection force 11. A method for producing an exterior material for an electricity storage device, comprising a step of obtaining a laminate in which, from the outside, at least a surface coating layer, a base material layer, a barrier layer, and a heat-sealable resin layer are laminated, in that order, and at least one layer outside the barrier layer contains a colorant.

12. An electricity storage device, comprising an electricity storage device element having at least a positive electrode, a negative electrode, and an electrolyte, housed in a packaging body formed from the exterior material for an electricity storage device according to claim 1 or 2.

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