JP7544880B2 - Molding packaging materials and molding cases - Google Patents

Description

The present invention relates to molded packaging materials and molded cases that are suitable for use, for example, as cases for notebook computers, mobile phones, in-vehicle devices, and stationary secondary batteries (lithium ion secondary batteries), and are also suitable for use as packaging materials for food and pharmaceutical products.

In recent years, as mobile electrical devices such as smartphones and tablet terminals have become thinner and lighter, a laminate consisting of a heat-resistant resin layer (base material layer), an outer adhesive layer, a metal foil layer, an inner adhesive layer, and a heat-sealable resin layer (inner sealant layer) has been used as the exterior material of the lithium ion secondary battery, lithium polymer secondary battery, lithium ion capacitor, electric double layer capacitor, and other power storage devices mounted on these devices instead of the conventional metal can (see Patent Document 1). In addition, power sources for electric vehicles, large power sources for power storage, capacitors, and the like are increasingly being exteriorized with the above-mentioned laminate (exterior material). The exterior material is molded into a three-dimensional shape such as a roughly rectangular parallelepiped shape by stretch molding or deep drawing. By molding into such a three-dimensional shape, it is possible to secure a storage space for accommodating the main body of the power storage device.

An exterior material having a matte coat layer provided on the outside of the base layer to protect the exterior material and improve its moldability is known (see Patent Document 2). The matte coat layer is made of a resin composition in which a heat-resistant resin contains 0.1% by mass to 1% by mass of inorganic fine particles having an average particle size of 1 μm to 10 μm. The provision of such a matte coat layer imparts good slip properties to the surface, improving moldability.

JP 2003-288865 A JP 2013-224014 A

Meanwhile, a protective tape is attached to the surface of the exterior material (surface of the matte coat layer) that forms the outer surface of the exterior material, for example, during the manufacturing process of the battery, in order to prevent defects in appearance such as scratches from occurring on the surface of the exterior material. However, there are cases where the matte coat layer peels off when the protective tape is peeled off after the battery is manufactured.

In addition, the surface of the matte coat layer, which is the outer surface of the packaging material, is printed with information such as the manufacturer's name, model number, capacity, lot number, barcode, CR code, etc., but sometimes this printing needs to be corrected. When this is done, the printing is wiped off with a cloth soaked in ethanol or MEK (methyl ethyl ketone). When this is done, there is also the problem that the matte coat layer (protective layer) is easily peeled off from the base layer (outer layer).

The present invention was made in consideration of this technical background, and aims to provide a molding packaging material and molding case that can prevent the protective layer from peeling off from the heat-resistant resin stretched film layer, including when the protective tape is peeled off, and that also has excellent organic solvent resistance.

To achieve the above objective, the present invention provides the following means:

[1] A molding packaging material comprising a heat-resistant resin stretched film layer as an outer layer, a thermoplastic resin layer as an inner layer, and a metal foil layer disposed between these two layers,
A moldable packaging material, characterized in that a protective layer is laminated and integrated onto the outer surface of the outer layer via an easy-adhesion layer.

[2] The moldable packaging material according to paragraph 1, wherein the easy-adhesion layer contains one or more resins selected from the group consisting of epoxy resins, urethane resins, acrylic ester resins, methacrylic ester resins, and polyethyleneimine resins.

[3] The molding packaging material described in the preceding paragraph 1, in which the easy-adhesion layer contains a urethane resin and an epoxy resin.

[4] The molding packaging material according to the preceding paragraph 3, in which the mass ratio of the urethane resin to the epoxy resin in the easy-adhesion layer is in the range of 98/2 to 40/60.

[5] The moldable packaging material according to paragraph 1, wherein the easy-adhesion layer contains one or more acrylic resins selected from the group consisting of acrylic acid ester resins and methacrylic acid ester resins, and an epoxy resin.

[6] The molding packaging material according to the preceding paragraph 5, wherein the mass ratio of the acrylic resin to the epoxy resin in the easy-adhesion layer is in the range of 98/2 to 40/60.

[7] The moldable packaging material according to any one of items 1 to 6, wherein the easy-adhesion layer is an adhesive layer formed by applying a resin-water emulsion to the heat-resistant resin stretched film layer.

[8] The moldable packaging material according to any one of items 1 to 7, wherein the protective layer is a layer made of a resin composition in which inorganic fine particles and/or organic fine particles are dispersed in a heat-resistant resin.

[9] A molded case made of a deep-drawn or bulged molded product of the moldable packaging material described in any one of items 1 to 8 above.

In the invention of [1], the protective layer is laminated and integrated onto the outer surface of the heat-resistant resin oriented film layer via an easy-adhesion layer, improving the adhesive strength between the heat-resistant resin oriented film layer and the protective layer, sufficiently preventing the protective layer from peeling off from the heat-resistant resin oriented film layer, including when the protective tape is peeled off, and improving organic solvent resistance.

In the invention of [2], the easy-adhesion layer is configured to contain one or more resins selected from the group consisting of epoxy resins, urethane resins, acrylic ester resins, methacrylic ester resins, and polyethyleneimine resins, so that the adhesive strength between the heat-resistant resin oriented film layer and the protective layer is improved, and peeling of the protective layer from the heat-resistant resin oriented film layer, including when the protective tape is peeled off, can be sufficiently prevented, and organic solvent resistance can be improved.

In the invention [3], the easy-adhesion layer contains a urethane resin and an epoxy resin, so that the adhesive strength between the heat-resistant resin oriented film layer and the protective layer is further improved, peeling of the protective layer from the heat-resistant resin oriented film layer can be more sufficiently prevented, and organic solvent resistance can be further improved.

In the invention [4], the mass ratio of the urethane resin/epoxy resin is in the range of 98/2 to 40/60, so that the adhesive strength between the heat-resistant resin oriented film layer and the protective layer is further improved, peeling of the protective layer from the heat-resistant resin oriented film layer can be more sufficiently prevented, and organic solvent resistance can be further improved.

In the invention [5], the easy-adhesion layer is configured to contain a specific acrylic resin and an epoxy resin, so that the adhesive strength between the heat-resistant resin oriented film layer and the protective layer is further improved, peeling of the protective layer from the heat-resistant resin oriented film layer can be more sufficiently prevented, and organic solvent resistance can be further improved.

In the invention [6], the mass ratio of acrylic resin/epoxy resin is in the range of 98/2 to 40/60, so that the adhesive strength between the heat-resistant resin stretched film layer and the protective layer is further improved, peeling of the protective layer from the heat-resistant resin stretched film layer can be more sufficiently prevented, and organic solvent resistance can be further improved.

In the invention [7], the easy-adhesion layer is an adhesive layer formed by applying a resin-water emulsion to the heat-resistant resin stretched film layer in advance, so that the adhesive strength between the heat-resistant resin stretched film layer and the protective layer is improved, and peeling of the protective layer from the heat-resistant resin stretched film layer can be sufficiently prevented, while improving organic solvent resistance.

In the invention of [8], the protective layer is made of a resin composition containing inorganic fine particles and/or organic fine particles dispersed in a heat-resistant resin, so that the surface hardness and slipperiness during molding of the protective layer can be further improved.

The invention of [9] provides a molded case that has excellent organic solvent resistance and does not peel off from the heat-resistant resin stretched film layer, even when the protective tape is peeled off.

1 is a cross-sectional view showing one embodiment of a moldable packaging material according to the present invention. 1 is a cross-sectional view showing one embodiment of an electricity storage device according to the present invention. 3 is a perspective view showing an exterior material (planar), an electricity storage device main body, and a molding case (a molded body molded into a three-dimensional shape) constituting the electricity storage device of FIG. 2 in a separated state before being heat-sealed.

One embodiment of the moldable packaging material 1 according to the present invention is shown in FIG. 1. This moldable packaging material 1 is used as a packaging material for lithium-ion secondary battery cases. That is, the moldable packaging material 1 is used as a secondary battery case after being subjected to molding such as deep drawing.

The molding packaging material 1 is configured such that a heat-resistant resin stretched film layer (outer layer) 2 is laminated to one surface of a metal foil layer 4 via a first adhesive layer 5, and a thermoplastic resin layer (inner layer) 3 is laminated to the other surface of the metal foil layer 4 via a second adhesive layer 6. Furthermore, a protective layer 20 is laminated to the outer surface of the heat-resistant resin stretched film layer 2 (the surface opposite to the metal foil layer) via a first easy-adhesion layer 11 (see FIG. 1).

In this embodiment, a first adhesive layer 11 is laminated on the outer surface of the heat-resistant resin stretched film layer 2 by gravure coating.

In this embodiment, a second easy-adhesion layer 12 is laminated on the lower surface (the surface on the metal foil layer side) of the heat-resistant resin stretched film layer 2, a colored ink layer 13 is laminated on the lower surface (the surface on the metal foil layer side) of the second easy-adhesion layer 12, and the colored ink layer 13 and the metal foil layer 4 are bonded and integrated via a first adhesive layer 5 (see FIG. 1). That is, the colored ink layer 13 is disposed between the metal foil layer 4 and the heat-resistant resin stretched film layer 2. In this embodiment, the second easy-adhesion layer 12 is laminated on the lower surface of the heat-resistant resin stretched film layer 2 by a gravure coating method, and the colored ink layer 13 is laminated on the lower surface of the second easy-adhesion layer 12 by printing.

In the present invention, the protective layer (matte coat layer) 20 is a layer made of a resin composition in which inorganic fine particles and/or organic fine particles are dispersed in a heat-resistant resin. The heat-resistant resin is preferably a two-component curing type heat-resistant resin. The content of at least one type of fine particles selected from the group consisting of inorganic fine particles and organic fine particles in the resin composition is preferably 0.1% by mass to 60% by mass. The average particle size of the inorganic fine particles and the organic fine particles is preferably 0.5 μm to 10 μm. Examples of the heat-resistant resin constituting the protective layer 20 include acrylic resins, epoxy resins, urethane resins, polyolefin resins, fluorine resins, and phenoxy resins, among which urethane resins are preferred. By providing such a protective layer 20, good slip properties are imparted to the surface, and a molding packaging material 1 with excellent moldability can be obtained. The thickness of the protective layer 20 is preferably set to 0.1 μm to 10 μm.

The inorganic fine particles are not particularly limited, but examples thereof include silica, alumina, calcium oxide, calcium carbonate, calcium sulfate, calcium silicate, etc., among which silica is preferably used. The organic fine particles are not particularly limited, but examples thereof include acrylic resin beads, styrene resin beads, urethane resin beads, etc., among which acrylic resin beads and urethane resin beads are preferably used. A lubricant can be added to the protective layer 20. The lubricant is not particularly limited, but examples thereof include fatty acid amides (erucic acid amide, behenic acid amide, stearic acid amide, oleic acid amide, ethylene bisstearic acid amide, etc.), waxes (polyethylene wax, polytetrafluoroethylene (PTFE) wax, etc.), etc.

The method for forming the protective layer 20 is not particularly limited, but examples thereof include a method of applying the resin composition for forming the protective layer 20 to the surface (outer surface) of the first adhesive layer 11 by a gravure coating method, a reverse roll coating method, a lip roll coating method, or the like.

The heat-resistant resin stretched film layer (outer layer) 2 is a member that is primarily responsible for ensuring good formability as a packaging material, that is, for preventing breakage due to necking of the metal foil during molding. The heat-resistant resin that constitutes the heat-resistant resin stretched film layer 2 is a heat-resistant resin that does not melt at the heat-sealing temperature when the moldable packaging material 1 is heat-sealed. As the heat-resistant resin, a heat-resistant resin having a melting point 10°C or higher than the melting point of the resin that constitutes the thermoplastic resin layer 3 is preferably used, and a heat-resistant resin having a melting point 20°C or higher than the melting point of the resin that constitutes the thermoplastic resin layer 3 is particularly preferably used.

In the present invention, the heat-resistant resin stretched film layer 2 is preferably composed of a heat-resistant resin stretched film having a hot water shrinkage rate of 2% to 20%. A hot water shrinkage rate of 2% or more can sufficiently prevent the protective layer from peeling off from the heat-resistant resin stretched film layer, and a hot water shrinkage rate of 20% or less can sufficiently prevent the protective layer from peeling off from the heat-resistant resin stretched film layer when forming such as deep drawing or stretch forming is performed. In particular, it is preferable to use a heat-resistant resin stretched film having a hot water shrinkage rate of 2.5 to 10% as the heat-resistant resin stretched film. Furthermore, it is more preferable to use a heat-resistant resin stretched film having a hot water shrinkage rate of 3.0% to 6.0%, and it is particularly preferable to use a heat-resistant resin stretched film having a hot water shrinkage rate of 3.5% to 5.0%.

The "hot water shrinkage rate" is the rate of dimensional change in the stretching direction of a test piece (10 cm x 10 cm) of heat-resistant resin stretched film 2 before and after immersion in hot water at 95°C for 30 minutes, and is calculated by the following formula.

Hot water shrinkage rate (%) = {(X-Y)/X} x 100
X: Dimension in the stretching direction before immersion treatment. Y: Dimension in the stretching direction after immersion treatment.

When a biaxially stretched film is used, the hot water shrinkage rate is the average value of the dimensional change rate in the two stretching directions.

The hot water shrinkage rate of the heat-resistant resin stretched film can be controlled, for example, by adjusting the heat setting temperature during stretching.

The heat-resistant resin stretched film layer (outer layer) 2 is not particularly limited, but examples thereof include stretched polyamide films such as stretched nylon films, stretched polyester films, etc. Among them, it is particularly preferable to use biaxially stretched polyamide films such as biaxially stretched nylon films, biaxially stretched polybutylene terephthalate (PBT) films, biaxially stretched polyethylene terephthalate (PET) films, or biaxially stretched polyethylene naphthalate (PEN) films as the heat-resistant resin stretched film layer 2. It is also preferable to use a heat-resistant resin biaxially stretched film stretched by a simultaneous biaxial stretching method as the heat-resistant resin stretched film layer 2. It is also preferable to use a heat-resistant resin biaxially stretched film in which the ratio (MD/TD) of the "hot water shrinkage rate in the M direction" to the "hot water shrinkage rate in the T direction" is in the range of 0.9 to 1.1. When the ratio (MD/TD) is in the range of 0.9 to 1.1, a molding packaging material with particularly good moldability can be obtained. The "M direction" means the "machine flow direction," and the "T direction" means the "direction perpendicular to the M direction." The nylon is not particularly limited, but examples include nylon 6, nylon 6,6, and MXD nylon. The heat-resistant resin stretched film layer 2 may be formed as a single layer (a single stretched film), or may be formed as a multilayer of, for example, a stretched polyester film/stretched polyamide film (such as a multilayer of a stretched PET film/stretched nylon film).

Among these, it is preferable to use a biaxially oriented polyamide film having a shrinkage rate of 2 to 20%, a biaxially oriented polyethylene naphthalate (PEN) film having a shrinkage rate of 2 to 20%, or a biaxially oriented polyethylene terephthalate (PET) film having a shrinkage rate of 2 to 20% as the heat-resistant resin stretched film layer 2. In this case, the effect of preventing the protective layer 20 from peeling off from the heat-resistant resin stretched film layer 2 can be further improved, including when the protective tape is peeled off from the protective layer 20.

The thickness of the heat-resistant resin stretched film layer 2 is preferably 6 μm to 50 μm. When a polyester film is used, the thickness is preferably 9 μm to 50 μm, and when a nylon film is used, the thickness is preferably 12 μm to 50 μm. By setting the thickness to above the preferred lower limit, sufficient strength as a packaging material can be ensured, and by setting the thickness to below the preferred upper limit, stress during stretch molding or drawing can be reduced, improving formability.

In the present invention, it is necessary to laminate the first easy-adhesion layer 11 on the outer surface (the surface opposite to the metal foil layer) of the heat-resistant resin stretched film layer 2. That is, the protective layer 20 is laminated integrally with the first easy-adhesion layer 11 on the outer surface of the heat-resistant resin stretched film layer 2 (see FIG. 1). By coating the surface of the heat-resistant resin stretched film layer 2, which originally has poor adhesion, with a polar resin or the like having excellent adhesion and tackiness, and laminating the first easy-adhesion layer 11, it is possible to improve the adhesion and adhesion with the protective layer 20. In addition, it is preferable to perform a corona treatment or the like on the outer surface of the heat-resistant resin stretched film layer 2 (the surface on which the first easy-adhesion layer 11 is laminated) in advance to increase wettability before laminating the first easy-adhesion layer 11.

In addition, in the present invention, it is preferable to perform a corona treatment on the inner surface (the surface on the metal foil layer side) of the heat-resistant resin stretched film layer 2, or to laminate an easy-adhesion layer (second easy-adhesion layer) 12 on the inner surface (the surface on the metal foil layer side). When laminating the easy-adhesion layer (second easy-adhesion layer) 12, the surface of the heat-resistant resin stretched film layer 2, which originally has poor adhesion, is coated with a polar resin or the like having excellent adhesion and adhesiveness, and then the second easy-adhesion layer 12 is laminated, thereby improving the adhesion and adhesion with the colored ink layer 13. It is preferable to perform a corona treatment or the like on the inner surface of the heat-resistant resin stretched film layer 2 (the surface on which the second easy-adhesion layer 12 is laminated) in advance to increase the wettability before laminating the second easy-adhesion layer 12.

The method for forming the first easy-adhesion layer 11 and the second easy-adhesion layer 12 is not particularly limited, but for example, the easy-adhesion layers 11 and 12 can be formed by applying an aqueous emulsion (water-based emulsion) of one or more resins selected from the group consisting of epoxy resins, urethane resins, acrylic ester resins, methacrylic ester resins, and polyethyleneimine resins to the surface of the heat-resistant resin stretched film 2 and drying it. The application method is not particularly limited, but examples thereof include a spray coating method, a gravure roll coating method, a reverse roll coating method, and a lip coating method.

The first easy-adhesion layer 11 and the second easy-adhesion layer 12 are preferably each configured to contain one or more resins selected from the group consisting of epoxy resins, urethane resins, acrylic ester resins, methacrylic ester resins, and polyethyleneimine resins. When the first easy-adhesion layer 11 is configured as described above, peeling of the protective layer 20 from the heat-resistant resin stretched film layer 2 can be more sufficiently prevented. Furthermore, when the second easy-adhesion layer 12 is configured as described above, the adhesive strength between the heat-resistant resin stretched film layer 2 and the colored ink layer 13 can be further improved.

Among them, it is particularly preferable that the first easy-adhesion layer 11 and the second easy-adhesion layer 12 are each configured to contain a urethane resin and an epoxy resin, or a (meth)acrylic acid ester resin and an epoxy resin. When the first easy-adhesion layer 11 has the particularly preferable configuration, peeling of the protective layer 20 from the heat-resistant resin stretched film layer 2 can be more sufficiently prevented. In addition, when the second easy-adhesion layer 12 has the particularly preferable configuration, the adhesive strength between the heat-resistant resin stretched film layer 2 and the colored ink layer 13 can be further improved.

When the former configuration is adopted, the content mass ratio of the urethane resin/epoxy resin in the first and second easy-adhesion layers 11 and 12 is preferably in the range of 98/2 to 40/60. When such a content mass ratio (range) is adopted in the first easy-adhesion layer 11, the protective layer 20 can be more sufficiently prevented from peeling off from the heat-resistant resin stretched film layer 2, and when such a content mass ratio (range) is adopted in the second easy-adhesion layer 12, the adhesive strength between the heat-resistant resin stretched film layer 2 and the colored ink layer 13 can be further improved. When the content ratio of the urethane resin is greater than the content mass ratio of the urethane resin/epoxy resin (98/2), the degree of crosslinking is insufficient, making it difficult to obtain sufficient solvent resistance and adhesive strength, which is not preferable. On the other hand, when the content ratio of the urethane resin is smaller than the content mass ratio of the urethane resin/epoxy resin (40/60), it takes too long to complete the crosslinking, which is not preferable. In particular, it is more preferable that the mass ratio of urethane resin/epoxy resin in the first and second adhesive layers 11 and 12 is in the range of 90/10 to 50/50.

In addition, when the latter configuration is adopted, the content mass ratio of the (meth)acrylic ester resin/epoxy resin in the first and second easy-adhesion layers 11 and 12 is preferably in the range of 98/2 to 40/60. When such a content mass ratio (range) is adopted in the first easy-adhesion layer 11, peeling of the protective layer 20 from the heat-resistant resin stretched film layer 2 can be more sufficiently prevented, and when such a content mass ratio (range) is adopted in the second easy-adhesion layer 12, the adhesive strength between the heat-resistant resin stretched film layer 2 and the colored ink layer 13 can be further improved. If the content ratio of the (meth)acrylic ester resin is larger than the content mass ratio of the (meth)acrylic ester resin/epoxy resin (98/2), the degree of crosslinking is insufficient, making it difficult to obtain sufficient solvent resistance and adhesive strength, which is not preferable. On the other hand, if the content ratio of the (meth)acrylic acid ester resin is smaller than the content ratio by mass of the (meth)acrylic acid ester resin/epoxy resin (40/60), it takes too long to complete the crosslinking, which is not preferable. In particular, it is more preferable that the content ratio by mass of the (meth)acrylic acid ester resin/epoxy resin in the first and second adhesive layers 11 and 12 is in the range of 90/10 to 50/50.

The resin aqueous emulsion (resin-aqueous emulsion) for forming the first easy-adhesion layer 11 and the second easy-adhesion layer 12 may contain surfactants such as glycols and ethylene oxide adducts of glycols. In this case, a sufficient defoaming effect can be obtained in the resin aqueous emulsion, so that the first easy-adhesion layer 11 and the second easy-adhesion layer 12 having excellent surface smoothness can be formed. The surfactant is preferably contained in the resin aqueous emulsion in an amount of 0.01% by mass to 2.0% by mass.

The resin aqueous emulsion (resin-aqueous emulsion) for forming the first easy-adhesion layer 11 and the second easy-adhesion layer 12 preferably contains inorganic fine particles such as silica and colloidal silica, and in this case, a blocking prevention effect can be obtained. The inorganic fine particles are preferably added in an amount of 0.1 to 10 parts by mass per 100 parts by mass of the resin content.

The formation amount (solid content after drying) of the first easy-adhesion layer 11 and the second easy-adhesion layer 12 is preferably in the range of 0.01 g/m ² to 0.5 g/m ² , respectively. When it is 0.01 g/m ² or more, the first easy-adhesion layer 11 can sufficiently bond the heat-resistant resin stretched film layer 2 and the protective layer 20, and the second easy-adhesion layer 12 can sufficiently bond the heat-resistant resin stretched film layer 2 and the colored ink layer 13. In addition, when it is 0.5 g/m ² or less, costs can be reduced and it is economical.

The resin content (content after drying) in the first adhesion layer 11 and the second adhesion layer 12 is preferably 88% by mass to 99.9% by mass.

The thermoplastic resin layer (inner layer) 3 provides excellent chemical resistance against highly corrosive electrolytes used in lithium ion secondary batteries and the like, and also provides the packaging material with heat sealability.

The thermoplastic resin layer 3 is preferably, but not limited to, an unstretched thermoplastic resin film layer. The thermoplastic resin unstretched film layer 3 is preferably, but not limited to, an unstretched film made of at least one thermoplastic resin selected from the group consisting of polyethylene, polypropylene, olefin copolymers, acid-modified products thereof, and ionomers. Of these, a three-layer laminate structure in which a coating layer containing random polypropylene is laminated on both sides of an intermediate layer containing block polypropylene is more preferable. The thermoplastic resin layer 3 may be a single layer or a multilayer.

The thickness of the thermoplastic resin layer 3 is preferably set to 20 μm to 80 μm. By setting the thickness to 20 μm or more, the occurrence of pinholes can be sufficiently prevented, and by setting the thickness to 80 μm or less, the amount of resin used can be reduced, thereby reducing costs. In particular, it is particularly preferable that the thickness of the thermoplastic resin layer 3 is set to 30 μm to 50 μm.

The metal foil layer 4 serves to provide the moldable packaging material 1 with gas barrier properties that prevent the intrusion of oxygen and moisture. The metal foil layer 4 is not particularly limited, but examples include aluminum foil, copper foil, nickel foil, and stainless steel foil, and aluminum foil is generally used. Aluminum foil is preferably A8079 or A8021 as specified in JIS H4160. The thickness of the metal foil layer 4 is preferably 20 μm to 100 μm. A thickness of 20 μm or more can prevent the occurrence of pinholes during rolling when manufacturing the metal foil, and a thickness of 100 μm or less can reduce stress during stretch forming and drawing, improving formability.

It is preferable that at least the inner surface 4a (the surface on the inner layer 3 side) of the metal foil layer 4 is subjected to a chemical conversion treatment. By performing such a chemical conversion treatment, corrosion of the metal foil surface due to the contents (battery electrolyte, food, medicine, etc.) can be sufficiently prevented. For example, the chemical conversion treatment is performed on the metal foil by carrying out the following treatment. That is, for example, the surface of the metal foil that has been subjected to a degreasing treatment is subjected to the following treatment.
The chemical conversion treatment is carried out by applying and then drying either of the following: 1) an aqueous solution consisting of a mixture of phosphoric acid, chromic acid, and a metal salt of a fluoride; 2) an aqueous solution consisting of a mixture of phosphoric acid, chromic acid, a metal salt of a fluoride, and a non-metal salt; or 3) an aqueous solution consisting of a mixture of an acrylic resin and/or a phenolic resin, phosphoric acid, chromic acid, and a metal salt of a fluoride.

In the present invention, a colored ink layer 13 may be provided between the heat-resistant resin stretched film layer (outer layer) 2 and the metal foil layer 4 (see FIG. 1). By providing such a colored ink layer 13, it is possible to impart color (including achromatic color) to the outer surface side (protective layer 20 side) of the moldable packaging material 1.

The colored ink layer 13 is not particularly limited, but examples thereof include a black ink layer, a white ink layer, a gray ink layer, a red ink layer, a blue ink layer, a green ink layer, and a yellow ink layer.

The black ink layer 13 will now be described. The black ink layer 10 is usually formed from a composition containing carbon black.

In particular, the black ink layer 13 is preferably configured to contain carbon black, diamine, polyol, and a hardener, but is not limited to this configuration.

In the black ink layer (ink layer after drying) 13, the carbon black content is preferably 15% to 60% by mass, and the total content of the diamine, polyol, and curing agent is preferably 40% to 85% by mass. Of these, it is particularly preferable that the carbon black content is 20% to 50% by mass.

If the carbon black content is less than 15% by mass, the metallic luster of the metal foil layer 4 will remain, impairing the sense of solidity, and partial color unevenness will occur when molding, which is not preferred. On the other hand, if the carbon black content exceeds 60% by mass, the black ink layer 13 will become hard and brittle, reducing the adhesive strength to the metal foil layer 4 and making it easier for peeling to occur between the metal foil layer 4 and the black ink layer 13 during molding, which is not preferred.

The black ink layer 13 preferably contains 2 to 20 parts by mass of the curing agent per 100 parts by mass of the total amount of the carbon black, the diamine, and the polyol. If the curing agent is less than 2 parts by mass, peeling between the metal foil layer 4 and the black ink layer 13 is likely to occur during molding, and if the curing agent is more than 20 parts by mass, blocking occurs when the rolled-up molding packaging material 1 is unwound, causing problems such as transfer and adhesion to the outer surfaces of the protective layer 20 and the thermoplastic resin layer 3, which is not preferable.

It is preferable to use carbon black with an average particle size of 0.2 μm to 5 μm.

The diamine is not particularly limited, but examples thereof include ethylenediamine, dimer diamine, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, dicyclohexylmethanediamine, and 2-hydroxyethylpropylenediamine. Among these, it is preferable to use one or more diamines selected from the group consisting of ethylenediamine, dimer diamine, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, and dicyclohexylmethanediamine as the diamine.

The diamine reacts with the curing agent (such as isocyanate) faster than the polyol, and can achieve curing in a short time. In other words, the diamine reacts with the curing agent together with the polyol, promoting cross-linking and curing of the ink composition.

The polyol is not particularly limited, but it is preferable to use one or more polyols selected from the group consisting of polyurethane polyols, polyester polyols, and polyether polyols.

The number average molecular weight of the polyol is preferably in the range of 1000 to 8000. Having a number average molecular weight of 1000 or more can increase the adhesive strength after curing, while having a number average molecular weight of 8000 or less can increase the reaction rate with the curing agent.

The curing agent is not particularly limited, but examples thereof include isocyanate compounds. Examples of the isocyanate compound that can be used include various aromatic, aliphatic, and alicyclic isocyanate compounds. Specific examples include tolylene diisocyanate (TDI), diphenylmethane diisocyanate, hexamethylene diisocyanate (HDI), isophorone diisocyanate, xylylene diisocyanate, and polymers of these isocyanates (adducts with polyhydric alcohols, isocyanurates, biuret compounds, etc.).

The colored ink layer (excluding the black ink layer) will now be described. The colored ink layer (excluding the black ink layer) 13 is preferably composed of a cured film of a colored ink composition containing a two-component curing polyester urethane resin binder made of a polyester resin as a base material and a polyfunctional isocyanate compound as a curing agent, and a colored pigment containing an inorganic pigment.

The color pigment is preferably one containing at least an inorganic pigment. In addition to the inorganic pigment, examples of the color pigment include azo pigments, phthalocyanine pigments, and condensed polycyclic pigments. The inorganic pigment is not particularly limited, but examples include carbon black, calcium carbonate, titanium oxide, zinc oxide, iron oxide, and aluminum powder. It is preferable to use inorganic pigments with an average particle size of 0.1 μm to 5 μm, and it is particularly preferable to use inorganic pigments with an average particle size of 0.5 μm to 2.5 μm. When dispersing the color pigment, it is preferable to disperse the color pigment using a pigment dispersing machine. When dispersing the color pigment, a pigment dispersant such as a surfactant can also be used.

It is preferable that 50% by mass or more of the color pigment is composed of the inorganic pigment. In this case, it is possible to form a color ink layer 13 of a specific color tone that can obtain a sufficient hiding power for hiding the metal foil layer 4 and can sufficiently impart a sense of dignity and luxury. In particular, it is more preferable that 60% by mass or more of the color pigment is composed of the inorganic pigment.

The thickness of the colored ink layer 13 (after drying) is preferably 1 μm to 4 μm. If the thickness is 1 μm or more, the color tone of the colored ink layer 10 will not remain transparent, and the color and gloss of the metal foil layer 4 can be sufficiently concealed. Furthermore, if the thickness is 4 μm or less, partial cracking of the colored ink layer 10 during molding can be sufficiently prevented.

The colored ink layer 13 is not particularly limited, but may be, for example,
It can be formed by printing (applying) 1) an ink composition containing carbon black, diamine, polyol, a curing agent and an organic solvent, or 2) a colored ink composition containing a two-component curing type polyester urethane resin binder made of a polyester resin as a base material and a polyfunctional isocyanate compound as a curing agent, and a colored pigment containing an inorganic pigment, by a gravure printing method or the like, on the surface of the second easy-adhesion layer 12 on the lower surface of the heat-resistant resin stretched film layer 2. The organic solvent is not particularly limited, and examples thereof include toluene, methyl ethyl ketone, ethyl acetate, and normal propyl acetate.

The method for forming the colored ink layer 13 is not particularly limited, but examples include gravure printing, reverse roll coating, and lip roll coating.

The first adhesive layer 5 is not particularly limited, and examples thereof include an adhesive layer formed by a two-liquid reactive adhesive. Examples of the two-liquid reactive adhesive include a two-liquid reactive adhesive composed of a first liquid consisting of one or more polyols selected from the group consisting of polyurethane polyols, polyester polyols, and polyether polyols, and a second liquid (curing agent) consisting of an isocyanate. The first adhesive layer 5 is formed, for example, by applying an adhesive such as the two-liquid reactive adhesive to the "upper surface of the metal foil layer 4" and/or to the "lower surface of the colored ink layer 13 laminated on the lower surface of the heat-resistant resin layer 2 via the second easy-adhesion layer 12" by a method such as gravure coating.

The second adhesive layer 6 is not particularly limited, but examples thereof include an adhesive layer formed from a polyurethane adhesive, an acrylic adhesive, an epoxy adhesive, a polyolefin adhesive, an elastomer adhesive, a fluorine adhesive, etc. Among these, it is preferable to use an acrylic adhesive or a polyolefin adhesive, and in this case, the electrolyte resistance and water vapor barrier properties of the molding packaging material 1 can be improved.

The molded packaging material 1 of the present invention described above can be molded (deep drawing, stretch molding, etc.) to obtain a molded case (battery case, etc.) 10 (see Figure 3). The exterior material 1 of the present invention can also be used as is without being molded (see Figure 3).

FIG. 2 shows an embodiment of an electric storage device 30 constructed using the molding packaging material 1 of the present invention. This electric storage device 30 is a lithium ion secondary battery. In this embodiment, as shown in FIGS. 2 and 3, an exterior member 15 is constructed by a molding case 10 obtained by molding the molding packaging material 1 and a planar packaging material 1. Thus, a roughly rectangular parallelepiped electric storage device main body (electrochemical element, etc.) 31 is accommodated in the accommodation recess of the molding case 10 obtained by molding the molding packaging material 1 of the present invention, and the packaging material 1 of the present invention is placed on the electric storage device main body 31 with its heat-sealable resin layer 3 side facing inward (lower side) without being molded, and the peripheral portion of the heat-sealable resin layer 3 of the planar packaging material 1 and the heat-sealable resin layer 3 of the flange portion (sealing peripheral portion) 29 of the molding case 10 are sealed and sealed by heat sealing to construct the electric storage device 30 of the present invention (see FIGS. 2 and 3). The inner surface of the storage recess of the molded case 10 is a heat-sealable resin layer 3, and the outer surface of the storage recess is a protective layer 20 (see Figure 3).

In FIG. 2, 39 is a heat seal portion where the peripheral portion of the packaging material 1 and the flange portion (sealing peripheral portion) 29 of the molded case 10 are joined (welded). In the energy storage device 30, the tip of the tab lead connected to the energy storage device main body 31 is led out to the outside of the exterior member 15, but is not shown in the figure.

The electric storage device main body 31 is not particularly limited, but examples thereof include a battery main body, a capacitor main body, a condenser main body, etc.

In the above embodiment, the exterior member 15 is configured to include a molded case 10 obtained by molding the moldable packaging material 1 and a planar packaging material 1 (see Figures 2 and 3), but is not limited to this combination. For example, the exterior member 15 may be configured to include a pair of molded cases 10.

Next, specific examples of the present invention will be described, but the present invention is not particularly limited to these examples.

<Adhesive for forming first and second easy-adhesion layers>
(Adhesive composition W)
70 parts by mass of "Takelac W-6010" manufactured by Mitsui Chemicals, Inc. as an aqueous urethane resin, 30 parts by mass of "Denacol EX-521" manufactured by Nagase Chemtec Corporation as an aqueous epoxy resin, and 5 parts by mass of colloidal silica "Snowtex ST-C" (average particle size 10 nm to 20 nm) manufactured by Nissan Chemical Industries, Ltd. as an anti-blocking agent were mixed, and further diluted with ion exchanged water to obtain an adhesive composition W having a non-volatile content of 2 mass%.
(Adhesive Composition V)
70 parts by mass of "Rikabond SA-513" manufactured by Chuo Rika Kogyo Co., Ltd. as an aqueous acrylic ester resin, 30 parts by mass of "Denacol EX-521" manufactured by Nagase Chemtec Corporation as an aqueous epoxy resin, and 5 parts by mass of colloidal silica "Snowtex ST-C" (average particle size 10 nm to 20 nm) manufactured by Nissan Chemical Industries, Ltd. as an anti-blocking agent were mixed and further diluted with ion exchanged water to obtain adhesive composition V having a non-volatile content of 2 mass%.
(Adhesive composition Z)
100 parts by mass of "Denacol EX-521" manufactured by Nagase Chemtec Corporation as a water-based epoxy resin and 5 parts by mass of colloidal silica "Snowtex ST-C" (average particle size 10 nm to 20 nm) manufactured by Nissan Chemical Industries, Ltd. as an anti-blocking agent were mixed, and the mixture was further diluted with ion-exchanged water to obtain adhesive composition Z having a non-volatile content of 2 mass%.

Example 1
A base material was obtained by blending 50 parts by mass of carbon black having an average particle size of 0.8 μm, 5 parts by mass of ethylenediamine, and 45 parts by mass of polyester polyol (number average molecular weight: 2500). 3 parts by mass of tolylene diisocyanate (TDI) as a curing agent was blended with 100 parts by mass of the base material, and 50 parts by mass of toluene was further blended and thoroughly stirred to obtain an ink composition.

The adhesive composition W was applied by gravure roll coating to one surface (inner surface) of a biaxially oriented nylon (6 nylon) film (heat-resistant resin oriented film layer, MD/TD=0.95) 2 having a thickness of 15 μm and a hot water shrinkage rate of 4.0%, obtained by stretching using a simultaneous biaxial stretching method, and then dried. The adhesive composition W was then left in an environment of 40° C. for one day to allow a curing reaction to proceed, thereby forming a second easy-adhesion layer 12 having a formation amount of 0.1 g/m ² .

Next, the ink composition was printed (applied) onto the surface of the second adhesive layer 12 of the biaxially oriented nylon film 2 by gravure printing, and then left for one day in a 40°C environment to allow drying and crosslinking reactions to proceed, forming a black ink layer (colored ink layer) 13 with a thickness of 3 μm.

On the other hand, a chemical conversion treatment solution consisting of polyacrylic acid, a trivalent chromium compound, water, and alcohol was applied to both sides of an aluminum foil 4 having a thickness of 35 μm, and dried at 180° C. so that the amount of chromium deposited was 10 mg/m ² .

Next, the biaxially oriented nylon film 2 was bonded to one side of the chemically treated aluminum foil 4 via a polyester-based polyurethane adhesive 5 on the black ink layer (colored ink layer) 13 side, and then a 30 μm-thick unstretched polypropylene film (thermoplastic resin layer) 3 was bonded to the other side of the aluminum foil 4 via a polyacrylic adhesive 6, and then the laminate was obtained by leaving it in a 40°C environment for 5 days.

Furthermore, the adhesive composition W was applied to the outer surface (unlaminated surface; corona-treated) of the biaxially oriented nylon film 2 of the laminate by a gravure roll coating method, dried, and then left to stand for one day in a 40°C environment to allow the curing reaction to proceed, thereby forming a first easy-adhesion layer 11 having a formation amount of 0.1 g/ ^m2 .

Next, a resin composition consisting of 20 parts by weight of urethane resin, 3 parts by weight of powdered silica having an average particle size of 2 μm, 5 parts by weight of acrylic resin beads having an average particle size of 3 μm, 5 parts by weight of powdered barium sulfate having an average particle size of 1 μm, 1 part by weight of polytetrafluoroethylene (PTFE) wax having an average particle size of 3 μm, and 66 parts by weight of toluene was applied to the surface (outer surface) of the first easy-to-adhere layer 11 by gravure coating to form a protective layer 20 having a thickness of 2 μm, thereby obtaining the moldable packaging material 1 shown in FIG. 1.

Example 2
A moldable packaging material 1 shown in FIG. 1 was obtained in the same manner as in Example 1, except that a biaxially oriented 6 nylon film (MD/TD = 0.9) having a thickness of 15 μm and a hot water shrinkage rate of 2.5% obtained by stretching using a simultaneous biaxial stretching method was used instead of the biaxially oriented 6 nylon film (MD/TD = 0.95) having a thickness of 15 μm and a hot water shrinkage rate of 4.0%.

Example 3
Instead of the biaxially oriented nylon 6 film (MD/TD=0.95) having a thickness of 15 μm and a hot water shrinkage rate of 4.0%, a biaxially oriented nylon 6 film (MD/TD=1.0) having a thickness of 15 μm and a hot water shrinkage rate of 3.5% obtained by stretching using a simultaneous biaxial stretching method was used, and a resin composition consisting of 20 parts by mass of polyester resin, 3 parts by mass of powdered silica having an average particle size of 2 μm, 5 parts by mass of acrylic resin beads having an average particle size of 3 μm, 5 parts by mass of powdered barium sulfate having an average particle size of 1 μm, 1 part by mass of polytetrafluoroethylene (PTFE) wax having an average particle size of 3 μm, and 66 parts by mass of toluene was used as the resin composition for forming the protective layer 20, and a configuration was used in which the second easy-adhesion layer 12 was not provided (i.e., a black ink layer (colored ink layer) 13 was laminated directly on the inner surface (corona-treated) of the biaxially oriented nylon film 2), and a moldable packaging material 1 shown in FIG. 1 was obtained in the same manner as in Example 1.

Example 4
A biaxially stretched nylon 6 film (MD/TD = 1.1) having a thickness of 15 μm and a hot water shrinkage rate of 5.0% obtained by stretching using a simultaneous biaxial stretching method was used instead of the biaxially stretched nylon 6 film (MD/TD = 0.95) having a thickness of 15 μm and a hot water shrinkage rate of 4.0%, and the resin composition for forming the protective layer 20 was a resin composition consisting of 20 parts by mass of a urethane-based resin, 3 parts by mass of powdered alumina having an average particle size of 1 μm, 5 parts by mass of acrylic resin beads having an average particle size of 3 μm, 5 parts by mass of powdered barium sulfate having an average particle size of 1 μm, 1 part by mass of polytetrafluoroethylene (PTFE) wax having an average particle size of 3 μm, and 66 parts by mass of toluene. A moldable packaging material 1 shown in FIG. 1 was obtained in the same manner as in Example 1, except that a resin composition was used for forming the protective layer 20, which

Example 5
A biaxially oriented polyethylene terephthalate (PET) film (MD/TD = 1.1) having a thickness of 15 μm and a hot water shrinkage rate of 2.0%, obtained by stretching using a simultaneous biaxial stretching method, was used instead of the biaxially oriented nylon 6 film (MD/TD = 0.95) having a thickness of 15 μm and a hot water shrinkage rate of 4.0%, and the resin composition for forming the protective layer 20 was a resin composition consisting of 20 parts by mass of a urethane-based resin, 3 parts by mass of powdered calcium carbonate having an average particle size of 2 μm, 5 parts by mass of acrylic resin beads having an average particle size of 3 μm, 5 parts by mass of powdered barium sulfate having an average particle size of 1 μm, 1 part by mass of polytetrafluoroethylene (PTFE) wax having an average particle size of 3 μm, and 66 parts by mass of toluene. A moldable packaging material 1 shown in FIG. 1 was obtained in the same manner as in Example 1, except that a resin composition was used for forming the protective layer 20, the resin composition consisting of 20 parts by mass of a urethane-based resin, 3 parts by mass of powdered calcium carbonate having an average particle size of 2 μm, 5 parts by mass of acrylic resin beads having an average particle size of 3 μm, 5 parts by mass of powdered barium sulfate having an average particle size of 1 μm, 1 part by mass of polytetrafluoroethylene (PTFE) wax having an average particle size of 3 μm, and 66 parts by mass of toluene.

Example 6
The moldable packaging material 1 shown in FIG. 1 was obtained in the same manner as in Example 1, except that the first easy-adhesion layer 11 and the second easy-adhesion layer 12 were formed using adhesive composition V instead of adhesive composition W.

Example 7
The moldable packaging material 1 shown in FIG. 1 was obtained in the same manner as in Example 1, except that the first easy-adhesion layer 11 and the second easy-adhesion layer 12 were formed using adhesive composition Z instead of adhesive composition W.

Example 8
A biaxially oriented polyethylene terephthalate (PET) film (MD/TD=1.1) having a thickness of 15 μm and a hot water shrinkage rate of 5.0%, obtained by simultaneous biaxial orientation, was used instead of the biaxially oriented nylon 6 film (MD/TD=0.95) having a thickness of 15 μm and a hot water shrinkage rate of 4.0%, and a resin composition for forming the protective layer 20 was used, which was composed of 20 parts by mass of epoxy resin, 3 parts by mass of powdered silica having an average particle size of 2 μm, 5 parts by mass of acrylic resin beads having an average particle size of 3 μm, 5 parts by mass of powdered barium sulfate having an average particle size of 1 μm, 1 part by mass of polytetrafluoroethylene (PTFE) wax having an average particle size of 3 μm, and 66 parts by mass of toluene. Except for this, a moldable packaging material 1 shown in FIG. 1 was obtained in the same manner as in Example 7.

<Example 9>
The moldable packaging material 1 shown in FIG. 1 was obtained in the same manner as in Example 3, except that a biaxially oriented 6 nylon film (MD/TD=1.0) having a thickness of 15 μm and a hot water shrinkage rate of 4.0% was used instead of the biaxially oriented 6 nylon film (MD/TD=0.95) having a thickness of 15 μm and a hot water shrinkage rate of 3.5%, no corona treatment was performed on the outer surface of the biaxially oriented 6 nylon film, and a resin composition for forming the protective layer 20 was used that consisted of 20 parts by mass of polyester resin, 3 parts by mass of powdered alumina having an average particle size of 1 μm, 5 parts by mass of acrylic resin beads having an average particle size of 3 μm, 5 parts by mass of powdered barium sulfate having an average particle size of 1 μm, 1 part by mass of polytetrafluoroethylene (PTFE) wax having an average particle size of 3 μm, and 66 parts by mass of toluene.

<Comparative Example 1>
A molding packaging material was obtained in the same manner as in Example 2, except that the first adhesion layer 11 was not provided (i.e., the protective layer 20 was laminated directly onto the outer surface (corona-treated) of the biaxially oriented nylon film 2).

<Comparative Example 2>
A molding packaging material was obtained in the same manner as in Example 3, except that the first adhesion layer 11 was not provided (i.e., the protective layer 20 was laminated directly onto the outer surface (corona-treated) of the biaxially oriented nylon film 2).

Each molding packaging material obtained as described above was evaluated according to the following evaluation methods. The results are shown in Table 1.

<Solvent Resistance Evaluation Method A (Ethanol Resistance)>
Using a Gakushin method friction fastness tester (with an aluminum jig with a load of 200 g) manufactured by Tester Sangyo Co., Ltd., an evaluation jig made of absorbent cotton wrapped around the aluminum jig and soaked in ethanol was brought back and forth in contact with the surface of the moldable packaging material (surface of protective layer 20) 20 times, and then the presence or absence and the degree of peeling of the protective layer were checked, and the ethanol resistance was evaluated based on the following judgment criteria.
(Judgment criteria)
"◯": no peeling of the protective layer was observed at all; "Δ": slight peeling of the protective layer was observed but was barely noticeable; "×": peeling of the protective layer was clearly observed.

<Solvent Resistance Evaluation Method B (MEK Resistance)>
Using a Gakushin method friction fastness tester (with an aluminum jig with a load of 200 g) manufactured by Tester Sangyo Co., Ltd., an evaluation jig made by wrapping absorbent cotton around the aluminum jig and impregnating it with MEK (methyl ethyl ketone) was brought back and forth in contact with the surface of the moldable packaging material (surface of protective layer 20) 20 times, and then the presence or absence and the degree of peeling of the protective layer were checked, and the ethanol resistance was evaluated based on the following judgment criteria.
(Judgment criteria)
"◯": no peeling of the protective layer was observed at all; "Δ": slight peeling of the protective layer was observed but was barely noticeable; "×": peeling of the protective layer was clearly observed.

<Method for evaluating tape peel resistance (resistance to tape peeling)>
The molding packaging material was cut into a size of 10 cm long x 10 cm wide to obtain a test piece, which was then attached and fixed on a substrate with a double-sided adhesive tape having a strong adhesive force. A "Scotch tape #600" (protective tape) manufactured by 3M was attached to the surface of the test piece fixed on the substrate (the surface of the protective layer 20) with a roller load of 2 kg, and immediately thereafter, the protective tape was vigorously peeled off to observe the state of the protective layer. This "tape peeling test" was repeated 15 times, and the tape peeling resistance was evaluated based on the following criteria.
(Judgment criteria)
"◯": No peeling was observed in the protective layer even after 15 repeated tape peel tests; "Δ": No peeling was observed in the protective layer even after 10 repeated tape peel tests, but peeling was observed in the protective layer in the 11th, 12th, 13th, or 14th tape peel tests; "×": The protective layer peeled off before the tape peel test was repeated 10 times.

<Moldability evaluation method>
Using a straight mold with free molding depth, one-stage deep drawing was performed on the moldable packaging material under the following molding conditions, and the moldability was evaluated for each molding depth (6.0 mm, 5.5 mm, 5.0 mm, 4.5 mm, 4.0 mm, 3.5 mm, 3.0 mm, 2.5 mm, 2.0 mm), the maximum molding depth (mm) at which good molding without any pinholes at the corners could be performed was investigated, and the moldability was evaluated based on the following criteria. The presence or absence of pinholes was examined by visually observing the presence or absence of transmitted light passing through the pinholes.
(Molding conditions)
Mold...Punch: 33.3 mm x 53.9 mm, Die: 80 mm x 120 mm, Corner R: 2 mm, Punch R: 1.3 mm, Die R: 1 mm
Wrinkle holding pressure...gauge pressure: 0.475 MPa, actual pressure (calculated value): 0.7 MPa
Material: SC (carbon steel), punch R only chrome plated.
(Judgment criteria)
"◎": The maximum molding depth without pinholes or cracks is 5.5 mm or more (passed)
"○": The maximum molding depth at which pinholes and cracks do not occur is 4.5 mm or more and less than 5.5 mm (passed)
"△": The maximum molding depth at which pinholes and cracks do not occur is 3.0 mm or more and less than 4.5 mm (passed)
"X": The maximum forming depth at which pinholes and cracks do not occur is less than 3.0 mm.

As is clear from Table 1, the molding packaging materials of Examples 1 to 9 of the present invention not only had excellent moldability, but also adequately prevented the protective layer from peeling off from the heat-resistant resin stretched film layer, and also had excellent organic solvent resistance.

In contrast, Comparative Examples 1 and 2, which did not have the first easy-adhesion layer, had poor tape peel resistance, and Comparative Example 2 also had poor solvent resistance.

The moldable packaging material according to the present invention is suitable for use as a battery case for notebook computers, mobile phones, in-vehicle batteries, stationary lithium-ion polymer secondary batteries, etc., and is also suitable as a packaging material for food and medicine, but is not limited to these applications. In particular, it is suitable for use as a battery case.

1... Packaging material for molding 2... Heat-resistant resin stretched film layer (outer layer)
3...Thermoplastic resin layer (inner layer)
4... Metal foil layer 10... Molding case 11... First adhesive layer 20... Protective layer

Claims (8)

A molding packaging material comprising a heat-resistant resin stretched film layer as an outer layer, a thermoplastic resin layer as an inner layer, and a metal foil layer disposed between these layers,
A protective layer is laminated and integrated onto an outer surface of the outer layer via a first adhesive layer,
A second adhesive layer is laminated on the inner surface of the heat-resistant resin stretched film layer between the heat-resistant resin stretched film layer and the metal foil layer, and an adhesive layer is laminated on the inner side of the second adhesive layer;
The first easy-adhesion layer and the second easy-adhesion layer each contain one or more resins selected from the group consisting of epoxy resins, urethane resins, acrylic ester resins, methacrylic ester resins, and polyethyleneimine resins,
the adhesive layer is a two-liquid reactive adhesive comprising a first liquid comprising one or more polyols selected from the group consisting of polyurethane polyols, polyester polyols, and polyether polyols, and a second liquid comprising a curing agent comprising an isocyanate;
the heat-resistant resin constituting the protective layer contains one or more resins selected from the group consisting of acrylic resins, epoxy resins, urethane resins, polyolefin resins, fluorine resins, and phenoxy resins ;
A moldable packaging material , characterized in that the first easy-adhesion layer and the second easy-adhesion layer are composed of the same adhesive composition . The molding packaging material according to claim 1, wherein the first and second easy-adhesion layers contain a urethane resin and an epoxy resin. The molding packaging material according to claim 2, wherein the first easy-adhesion layer and the second easy-adhesion layer have a mass ratio of the urethane resin to the epoxy resin in the range of 98/2 to 40/60. The moldable packaging material according to claim 1, wherein the first and second easy-adhesion layers contain one or more acrylic resins selected from the group consisting of acrylic acid ester resins and methacrylic acid ester resins, and an epoxy resin. The molding packaging material according to claim 4, wherein the mass ratio of the acrylic resin to the epoxy resin in the first and second easy-adhesion layers is in the range of 98/2 to 40/60. The moldable packaging material according to any one of claims 1 to 5, wherein the first easy-adhesion layer and the second easy-adhesion layer are adhesive layers formed by applying a resin-water emulsion to the heat-resistant resin stretched film layer. 7. The moldable packaging material according to claim 1 , wherein the protective layer is a layer made of a resin composition containing inorganic fine particles dispersed in a heat-resistant resin. A molded case comprising a deep-drawn or bulged molded product of the moldable packaging material according to any one of claims 1 to 7 .

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