JP7294132B2 - Battery packaging materials and batteries - Google Patents

Description

TECHNICAL FIELD The present invention relates to a battery packaging material and a battery.

Conventionally, various types of batteries have been developed, and in all batteries, packaging materials have become indispensable members for sealing battery elements such as electrodes and electrolytes. Conventionally, metal packaging materials have been widely used as packaging materials for batteries.

On the other hand, in recent years, with the increasing performance of electric vehicles, hybrid electric vehicles, personal computers, cameras, mobile phones, etc., batteries are required to have various shapes and to be thinner and lighter. However, metal battery packaging materials, which have been widely used in the past, have drawbacks in that it is difficult to follow the diversification of shapes and there is a limit to weight reduction.

Therefore, in recent years, a film-like laminate in which a substrate layer/barrier layer/thermal adhesive resin layer is laminated in order has been developed as a battery packaging material that can be easily processed into various shapes and can be made thinner and lighter. A body has been proposed (see, for example, US Pat.

In such a battery packaging material, generally, recesses are formed by cold forming, battery elements such as electrodes and electrolyte are arranged in the spaces formed by the recesses, and the heat-sealable resin layers are bonded together. By heat-sealing, a battery in which the battery element is housed inside the battery packaging material can be obtained. However, such film-like packaging materials are thinner than metallic packaging materials, and have the disadvantage of being susceptible to pinholes and cracks during molding. If pinholes or cracks occur in the battery packaging material, the electrolyte may permeate the barrier layer and form metal deposits, which may result in short circuits. It is essential for battery packaging materials to have properties such that pinholes are unlikely to occur during molding, that is, to have excellent moldability.

JP 2008-287971 A

In recent years, along with the demand for smaller and thinner batteries, there is a demand for even thinner packaging materials for batteries. However, if the thickness of the battery packaging material composed of the above-described film-like laminate is extremely thin, for example, 100 μm or less, cracks and pinholes are likely to occur during molding, making it difficult to impart high moldability. There is a problem of becoming

A main object of the present invention is to provide a battery packaging material having excellent moldability in a battery packaging material comprising a laminate comprising at least a substrate layer, a barrier layer, and a heat-fusible resin layer in this order. That's what it is.

The present inventors have made extensive studies to solve the above problems. As a result, in the battery packaging material comprising a laminate comprising at least a substrate layer, a barrier layer, and a heat-fusible resin layer in this order, the thickness of the laminate was 100 µm or less, and the laminate met the following test conditions. Regarding the breaking energy per unit width 1m calculated from the curve of "measured load (N / 15mm) - displacement" measured when a tensile test is performed with the The total X+Y of the breaking energy X in the direction and the breaking energy Y in the other direction perpendicular to both the one direction and the thickness direction of the laminate is 200 J or more, so that the battery has excellent moldability. It was found that it can be used as a packaging material for The present invention has been completed through further studies based on these findings.
(Test condition)
Test speed: 50mm/min
Width of test piece: 15 mm
Gauge distance: 30 mm
The length of the test piece shall be 100 mm. However, if only a test piece with a length of less than 100 mm can be prepared, as long as possible (as close to 100 mm as possible) if the distance between gauge points can be secured and both ends of the test piece can be grasped during measurement is to be measured.

That is, the present invention provides a battery packaging material and a battery according to the following aspects.
Section 1. Consists of a laminate comprising at least a substrate layer, a barrier layer, and a heat-fusible resin layer in this order,
The laminate has a thickness of 100 μm or less,
For the laminate, the breaking energy per unit width of 1 m calculated from the measured load (N / 15 mm)-displacement curve measured when a tensile test is performed under the following test conditions. The total X + Y of the breaking energy X in one direction perpendicular to the thickness direction and the breaking energy Y in the other direction perpendicular to both the one direction and the thickness direction of the laminate is 200 J or more. Packaging materials for batteries.
(Test condition)
Test speed: 50mm/min
Width of test piece: 15 mm
Gauge distance: 30 mm
Section 2. Item 2. The battery packaging material according to item 1, wherein the one direction is the MD of the laminate, and the other direction is the TD of the laminate.
Item 3. Item 3. The battery packaging material according to Item 1 or 2, wherein the laminate has a puncture strength of 15 N or more measured from the base layer side by a method conforming to JIS Z1707:1995.
Section 4. Item 4. The battery packaging material according to any one of items 1 to 3, comprising an adhesive layer between the base layer and the barrier layer.
Item 5. Item 5. The battery packaging material according to Item 4, wherein the adhesive layer contains a coloring agent.
Item 6. Item 6. The battery packaging material according to Item 4 or 5, further comprising a colored layer between the base material layer and the adhesive layer.
Item 7. Item 7. The battery packaging material according to any one of Items 1 to 6, further comprising a surface coating layer on the opposite side of the base layer to the barrier layer.
Item 8. Item 8. A battery, wherein a battery element comprising at least a positive electrode, a negative electrode, and an electrolyte is housed in a package formed of the battery packaging material according to any one of items 1 to 7.

According to the present invention, in a battery packaging material comprising a laminate comprising at least a substrate layer, a barrier layer, and a heat-fusible resin layer in this order, the laminate has a very thin thickness of 100 μm or less. First, the breaking energy per unit width of 1 m calculated from the curve of "measured load (N / 15 mm) - displacement amount" measured when a tensile test is performed on the laminate under the above test conditions, The total X + Y of the breaking energy X in one direction perpendicular to the thickness direction of and the breaking energy Y in the other direction perpendicular to both the one direction and the thickness direction of the laminate is 200 J or more Thereby, a battery packaging material having excellent moldability can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows an example of the cross-sectional structure of the packaging material for batteries of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows an example of the cross-sectional structure of the packaging material for batteries of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows an example of the cross-sectional structure of the packaging material for batteries of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows an example of the cross-sectional structure of the packaging material for batteries of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows an example of the cross-sectional structure of the packaging material for batteries of this invention. 10 is a measured load (N/15 mm)-displacement curve (MD) obtained in a tensile test of the battery packaging material of Example 5. FIG. FIG. 10 is a schematic diagram showing a portion where the data of the measured load (N/15 mm)-displacement curve is integrated. FIG. 4 is a schematic diagram for explaining a curl evaluation method due to molding of the battery packaging material. FIG. 4 is a schematic diagram for explaining a curl evaluation method due to molding of the battery packaging material. FIG. 4 is a schematic diagram of a barrier layer of a test sample after molding in Examples.

The battery packaging material of the present invention comprises a laminate comprising at least a substrate layer, a barrier layer, and a heat-fusible resin layer in this order, the laminate having a thickness of 100 μm or less, is measured when a tensile test is performed under the following test conditions, the measured load (N / 15mm) - about the breaking energy per unit width 1m calculated from the displacement curve, the thickness direction of the laminate The total X+Y of the breaking energy X in one vertical direction and the breaking energy Y in the other direction perpendicular to both the one direction and the thickness direction of the laminate is 200 J or more. The battery packaging material of the present invention will be described in detail below.
(Test condition)
Test speed: 50mm/min
Width of test piece: 15 mm
Gauge distance: 30 mm

In this specification, the numerical range indicated by "-" means "more than" and "less than". For example, the notation of 2 to 15 mm means 2 mm or more and 15 mm or less.

1. Laminate Structure and Physical Properties of Battery Packaging Material The battery packaging material of the present invention comprises, for example, as shown in FIGS. It is composed of laminated laminates. In the battery packaging material of the present invention, the substrate layer 1 is the outermost layer, and the heat-fusible resin layer 4 is the innermost layer. That is, when the battery is assembled, the heat-sealable resin layers 4 positioned at the periphery of the battery element are heat-sealed to seal the battery element, thereby sealing the battery element.

In the battery packaging material of the present invention, for example, as shown in FIGS. may be provided. Further, the battery packaging material of the present invention, for example, as shown in FIGS. An adhesive layer 5 may also be provided. Moreover, as shown in FIGS. 4 and 5, a surface coating layer 6 may be provided on the outer side of the base material layer 1 (the side opposite to the heat-fusible resin layer 4), if necessary. Moreover, as shown in FIG. 5, a colored layer 7 may be provided between the substrate layer 1 and the adhesive layer 2, if necessary.

The laminate constituting the battery packaging material of the present invention has a thickness of 100 μm or less, and the “measured load (N / 15 mm) - displacement amount” measured when a tensile test is performed under the above test conditions. Regarding the breaking energy per unit width of 1 m calculated from the curve, the breaking energy X in one direction perpendicular to the thickness direction of the laminate (that is, the stacking direction of the laminate), the one direction and the thickness of the laminate direction and the other direction that is perpendicular to both (that is, the other direction is the direction perpendicular to the one direction and the direction perpendicular to the thickness direction of the laminate). The total X+Y is 200J or more. From the viewpoint of further improving moldability while reducing the thickness of the battery packaging material, the one direction is the MD (Machine Direction) of the laminate, and the other direction is the TD (Transverse Direction) of the laminate. Preferably. That is, the breaking energy per unit width of 1 m calculated from the curve of "measured load (N / 15 mm) - displacement amount" measured when the tensile test was performed under the above test conditions, the flow direction of the laminate It is preferable that the total X+Y of the breaking energy X in MD, which is , and the breaking energy Y in TD, which is in the vertical direction, is 200 J or more. In addition, in this invention, a tensile test means the test of a tensile property.

Further, from the viewpoint of improving moldability while reducing the thickness of the battery packaging material, the preferred upper limit of the total breaking energy X+Y is about 700 J or less, about 500 J or less, about 495 J or less, about 450 J or less, about 445 J or less, about 400 J or less, about less than about 400 J, about 380 J or less, and the lower limit is preferably about 250 J or more, more preferably about 300 J or more. The range of the total breaking energy X+Y is preferably about 200 to 700 J, about 200 to 500 J, about 200 to 495 J, about 200 to 450 J, about 200 to 445 J, about 200 to 400 J, about 200 J or more and less than about 400 J. , 200-380J, 250-700J, 250-500J, 250-495J, 250-450J, 250-445J, 250-400J, 250-400J, 250-380J, 300- about 700 J, about 300 to 500 J, about 300 to 495 J, about 300 to 450 J, about 300 to 445 J, about 300 to 400 J, about 300 J to less than about 400 J, and about 300 to 380 J.

As a method for setting the total breaking energy X+Y to 200 J or more, the materials and thicknesses of the base material layer, the barrier layer, and the heat-fusible resin layer constituting the laminate are adjusted. A layer that contributes most to the magnitude of the breaking energy is the base material layer. As the material constituting the base material layer, those described later are used, and further, in the manufacturing process of the base material layer, for example, the type of film forming method and the conditions at the time of film formation (e.g., film forming temperature, stretching ratio, cooling temperature , cooling rate, heat setting temperature after stretching) are adjusted as appropriate. Film-forming methods include, for example, a T-die method, a calender method, a tubular method, and the like. Moreover, in order to set the total breaking energy X+Y to 200 J or more, it is preferable to heat the laminate at an appropriate temperature for an appropriate time in the step of heating the laminate after laminating each layer. By adopting an appropriate temperature and time, it is possible to improve the adhesion of each layer while suppressing damage to the laminate, especially to the base material layer. The upper limit of the heating temperature in the heating step is preferably about 185° C. or less, more preferably about 180° C. or less, still more preferably 178° C. or less, and the lower limit of the heating temperature is preferably 150° C. or more, more preferably. is 160° C. or higher, more preferably 165° C. or higher. Preferred ranges of the heating temperature in the heating step are about 150 to 185°C, about 150 to 180°C, about 150 to 178°C, about 160 to 185°C, about 160 to 180°C, about 160 to 178°C, and 165 to 185°C. °C, about 160 to 180°C, and about 160 to 178°C. The upper limit of the heating time in the heating step is preferably 30 minutes or less, more preferably 15 minutes or less, and still more preferably 10 minutes or less, and the lower limit is preferably 0.1 minute or more, more preferably. 0.5 minutes or more, more preferably 1 minute or more. It is preferable to combine the heating temperature and the heating time in the heating step.

In the battery packaging material, the barrier layer, which will be described later, can usually be distinguished between MD and TD during the manufacturing process. For example, when the barrier layer is made of aluminum foil, linear streaks called so-called rolling marks are formed on the surface of the aluminum foil in the rolling direction (RD) of the aluminum foil. Since the rolling marks extend along the rolling direction, the rolling direction of the aluminum foil can be grasped by observing the surface of the aluminum foil. In addition, in the manufacturing process of the laminate, the MD of the laminate usually coincides with the RD of the aluminum foil, so the surface of the aluminum foil of the laminate is observed to identify the rolling direction (RD) of the aluminum foil. Thus, the MD of the laminate can be specified. Moreover, since the TD of the laminate is perpendicular to the MD of the laminate, the TD of the laminate can also be specified.

In the present invention, the rupture energies X and Y per unit width of 1 m in the one direction and the other direction of the laminate constituting the battery packaging material are obtained in the above test for the one direction and the other direction of the laminate, respectively. Obtain the data of the measured load (N / 15 mm) - displacement curve measured when the tensile test is performed under the conditions, save the data in csv file format, and use the spreadsheet software (Microsoft Excel (registered trademark)) is used to integrate the data until the laminate breaks. At this time, the breaking energy per 1 m width of each battery packaging material is converted (divided by 0.015) and calculated using the spreadsheet software. Then, the breaking energy per unit width of 1 m in one direction and the breaking energies X and Y per unit width of 1 m in the other direction are totaled. In addition, when the laminate is broken means when the test piece is broken. Five battery packaging materials to be measured are prepared, for example, among the breaking energy values for five samples, the average of three values excluding the maximum value and the minimum value is calculated as the breaking energy of the laminate. and Even if five samples cannot be prepared, it is preferable to use the average of the number of samples that can be measured. Moreover, in the tensile test, a commercially available tensile tester can be used.

In addition, from the viewpoint of improving moldability while reducing the thickness of the battery packaging material, the laminate constituting the battery packaging material of the present invention is prepared by a method conforming to JIS Z1707:1995. As for the puncture strength measured from the layer 1 side, the lower limit is preferably about 15 N or more, more preferably about 18 N or more, and even more preferably about 19 N or more, and the upper limit is preferably about 30 N or less. It is preferably about 25N or less, more preferably 22N or less. The range of the piercing strength is preferably about 15 to 30 N, about 15 to 25 N, about 18 to 30 N, about 18 to 25 N, about 18 to 22 N, about 19 to 30 N, about 19 to 25 N, About 19 to 22N can be mentioned. From the viewpoint of suppressing curling due to molding of the battery packaging material, the piercing strength is preferably about 22 N or less. The method for measuring the puncture strength of the laminate is as follows.

<Penetration strength of laminate>
The piercing strength from the substrate layer side of the laminate constituting the battery packaging material is measured by a method conforming to JIS Z1707:1995. Specifically, in a measurement environment of 23 ± 2 ° C. and relative humidity (50 ± 5)%, the test piece is fixed with a table with a diameter of 115 mm having an opening of 15 mm in the center and a pressing plate. A semicircular needle with a tip shape radius of 0.5 mm is pierced at a speed of 50±5 mm per minute, and the maximum stress until the needle penetrates is measured. The number of test pieces is 5, and the average value is obtained. In addition, when the number of test pieces is insufficient to measure 5, the number that can be measured is measured and the average value is obtained.

In addition, the wetting tension of the substrate layer 1 side of the laminate constituting the battery packaging material of the present invention is not particularly limited. , preferably about 30 to 60 mN/m. Methods for adjusting the wetting tension include a method of adjusting the amount of lubricant present on the surface of the substrate layer 1 side, and a method of applying a surface treatment (such as corona treatment) to the surface of the substrate layer 1 side. The method for measuring the wetting tension is as follows.

<Measurement of wet tension>
A wetting reagent conforming to JIS standards is used to measure the wetting tension of the substrate layer side of the laminate constituting the battery packaging material. The test method complies with JIS K6768:1999. Using the mixed liquid for wet tension test, apply the reagent soaked in a cotton swab in a line of about 6 cm ² on the surface of the base material layer constituting the battery packaging material, and check whether the liquid film breaks after 2 seconds. or If the liquid film is not broken, it proceeds to the next higher surface tension mixed liquid, and if it is broken, it proceeds to the next lower surface tension mixed liquid. Repeat this operation and select a mixture that can wet the surface of the test piece in 2 seconds. The wet tension is measured under an environment of 23° C. and a relative humidity of 50%.

Further, the battery packaging material of the present invention has a molding depth at which the thickness of the barrier layer 3 described later is 20 μm (that is, when the battery packaging material of the present invention is subjected to molding, the barrier layer of the battery packaging material has a thickness of 20 μm. 3) is preferably 4.5 mm or more, more preferably 5.0 mm or more, and the upper limit is preferably 10.0 mm or less, more preferably 8. It is 0 mm or less, and preferable ranges include about 4.5 to 10.0 mm, about 4.5 to 8.0 mm, about 5.0 to 10.0 mm, and about 5.0 to 8.0 mm. Specifically, the molding depth is a value measured by the method described in Examples.

In addition, the limit molding depth of the battery packaging material of the present invention is preferably 4.0 mm or more, more preferably 5.5 mm or more as the lower limit, and preferably 12.0 mm or less, more preferably 10 mm as the upper limit. 0 mm or less, and preferable ranges include about 4.0 to 12.0 mm, about 4.0 to 10.0 mm, about 5.5 to 12.0 mm, and about 5.5 to 10.0 mm. Specifically, the limit molding depth is a value measured by the method described in Examples.

The thickness of the laminate constituting the battery packaging material of the present invention is not particularly limited as long as it is 100 μm or less. It is preferably about 95 μm or less, more preferably about 89 μm or less, still more preferably about 75 μm or less, and the lower limit is preferably about 35 μm or more, more preferably about 45 μm or more. The thickness range of the laminate is preferably about 35 to 100 μm, about 35 to 95 μm, about 45 to 95 μm, about 35 to 89 μm, about 45 to 89 μm, about 35 to 75 μm, and about 45 to 75 μm. mentioned. Although the thickness of the laminate constituting the battery packaging material of the present invention is as thin as 100 μm or less, according to the present invention, excellent moldability can be exhibited. Therefore, the battery packaging material of the present invention can contribute to improving the energy density of the battery.

2. Each layer forming the battery packaging material [base layer 1]
In the battery packaging material of the present invention, the substrate layer 1 is the outermost layer. The material forming the base material layer 1 is not particularly limited as long as it has insulating properties. Examples of materials for forming the base layer 1 include polyester, polyamide, epoxy resin, acrylic resin, fluororesin, polyurethane, silicon resin, phenol resin, polyetherimide, polyimide, polycarbonate, and mixtures and copolymers thereof. etc.

Specific examples of polyesters include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, copolymer polyester mainly composed of repeating units of ethylene terephthalate, and butylene terephthalate mainly composed of repeating units. and copolymerized polyester. Further, as the copolymer polyester having ethylene terephthalate as the main repeating unit, specifically, a copolymer polyester polymerized with ethylene isophthalate having ethylene terephthalate as the main repeating unit (hereinafter referred to as polyethylene (terephthalate/isophthalate) ), polyethylene (terephthalate/isophthalate), polyethylene (terephthalate/adipate), polyethylene (terephthalate/sodium sulfoisophthalate), polyethylene (terephthalate/sodium isophthalate), polyethylene (terephthalate/phenyl-dicarboxylate) , polyethylene (terephthalate/decanedicarboxylate), and the like. Further, as the copolymer polyester having butylene terephthalate as the main repeating unit, specifically, a copolymer polyester polymerized with butylene isophthalate having butylene terephthalate as the main repeating unit (hereinafter referred to as polybutylene (terephthalate/isophthalate) ), polybutylene (terephthalate/adipate), polybutylene (terephthalate/sebacate), polybutylene (terephthalate/decanedicarboxylate), polybutylene naphthalate, and the like. These polyesters may be used singly or in combination of two or more. Polyester has the advantage of being excellent in electrolytic solution resistance and less likely to cause whitening or the like due to adhesion of the electrolytic solution.

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; terephthalic acid and/or isophthalic acid; Hexamethylenediamine-isophthalic acid-terephthalic acid copolymer polyamide such as nylon 6I, nylon 6T, nylon 6IT, nylon 6I6T (I represents isophthalic acid, T represents terephthalic acid) containing structural units derived from Polyamides containing aromatics such as pamido (MXD6); alicyclic polyamides such as polyaminomethylcyclohexyladipamide (PACM6); and copolymerization of lactam components and isocyanate components such as 4,4'-diphenylmethane-diisocyanate. polyester amide copolymers and polyether ester amide copolymers, which are copolymers of copolyamide and polyester or polyalkylene ether glycol; copolymers thereof, and the like. These polyamides may be used singly or in combination of two or more. The stretched polyamide film is excellent in stretchability and can prevent whitening due to cracking of the resin in the substrate layer 1 during molding.

The substrate layer 1 may be formed of a uniaxially or biaxially stretched resin film, or may be formed of an unstretched resin film. Among them, a uniaxially or biaxially stretched resin film, particularly a biaxially stretched resin film, is preferably used as the substrate layer 1 because its heat resistance is improved by oriented crystallization. Moreover, the base material layer 1 may be formed by coating the above material on the barrier layer 3 .

Among these, the resin film forming the substrate layer 1 is preferably nylon or polyester, more preferably biaxially oriented nylon or biaxially oriented polyester, particularly preferably biaxially oriented nylon.

The base material layer 1 can be formed by laminating (multilayer structure) at least one of resin films and coatings made of different materials in order to improve pinhole resistance and insulation when used as a battery package. be. Specific examples include a multilayer structure in which a polyester film and a nylon film are laminated, a multilayer structure in which a plurality of nylon films are laminated, a multilayer structure in which a plurality of polyester films are laminated, and the like. When the substrate layer 1 has a multilayer structure, a laminate of a biaxially stretched nylon film and a biaxially stretched polyester film, a laminate of a plurality of biaxially stretched nylon films, and a laminate of a plurality of biaxially stretched polyester films. A body is preferable, and as a specific example, a laminate obtained by laminating two layers of biaxially stretched nylon films is preferable. In addition, biaxially stretched polyester is, for example, resistant to discoloration when an electrolytic solution adheres to the surface. , The substrate layer 1 is preferably a laminate having biaxially oriented nylon and biaxially oriented polyester in this order from the barrier layer 3 side. When the substrate layer 1 has a multilayer structure, the thickness of each layer is preferably about 3 to 25 μm.

When the substrate layer 1 has a multi-layer structure, each resin film may be adhered via an adhesive, or may be directly laminated without an adhesive. In the case of bonding without using an adhesive, for example, a method of bonding in a heat-melted state such as a coextrusion method, a sandwich lamination method, a thermal lamination method, or the like can be used. Moreover, when bonding via an adhesive, the adhesive to be used may be a two-component curing adhesive or a one-component curing adhesive. Furthermore, the adhesion mechanism of the adhesive is not particularly limited, and may be any of a chemical reaction type, a solvent volatilization type, a heat melting type, a heat pressure type, an ultraviolet curing type, an electron beam curing type, and the like. Specific examples of the adhesive are the same as those exemplified for the adhesive layer 2 . Also, the thickness of the adhesive can be the same as that of the adhesive layer 2 .

In the present invention, from the viewpoint of improving the moldability of the battery packaging material, it is preferable that the surface of the substrate layer 1 is coated with a lubricant. The lubricant is not particularly limited, but preferably includes an amide-based lubricant. Specific examples of amide-based lubricants include saturated fatty acid amides, unsaturated fatty acid amides, substituted amides, methylolamides, saturated fatty acid bisamides, and unsaturated fatty acid 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, N-stearyl erucic acid amide and the like. Further, specific examples of methylolamide include methylol stearamide. Specific examples of saturated fatty acid bisamides include methylenebisstearic acid amide, ethylenebiscapric acid amide, ethylenebislauric acid amide, ethylenebisstearic acid amide, ethylenebishydroxystearic acid amide, ethylenebisbehenic acid amide, hexamethylenebisstearin. acid amide, hexamethylenebisbehenamide, hexamethylenehydroxystearic acid amide, N,N'-distearyladipic acid amide, N,N'-distearylsebacic acid amide and the like. Specific examples of unsaturated fatty acid bisamides include ethylenebisoleic acid amide, ethylenebiserucic acid amide, hexamethylenebisoleic acid amide, N,N'-dioleyladipic acid amide, and N,N'-dioleylsebacic acid amide. etc. Specific examples of fatty acid ester amides include stearamide ethyl stearate. Further, specific examples of the aromatic bisamide include m-xylylenebisstearic acid amide, m-xylylenebishydroxystearic acid amide, N,N'-distearylisophthalic acid amide and the like. Lubricants may be used singly or in combination of two or more.

The content of the lubricant in the base material layer 1 is not particularly limited, and from the viewpoint of enhancing the moldability and insulating properties of the electronic packaging material, it is preferably about 0.01 to 0.2% by mass, more preferably 0. 0.05 to 0.15% by mass.

The thickness of the substrate layer 1 is preferably about 8 μm or more, more preferably about 8 μm or more, more preferably about 8 μm or more, and more preferably about 10 μm or more, and the upper limit is preferably about 25 μm or less, more preferably about 20 μm or less. The range of thickness of the base layer 1 is preferably about 8 to 25 μm, about 8 to 20 μm, about 10 to 25 μm, and about 10 to 20 μm. In addition, in this invention, when the base material layer 1 is a multilayer structure adhere|attached with the adhesive agent, the thickness of the said adhesive agent is not included in the thickness of the base material layer 1. FIG.

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

The adhesive layer 2 is made of an adhesive capable of bonding the base material layer 1 and the barrier layer 3 together. The adhesive used to form the adhesive layer 2 may be a two-component curing adhesive or a one-component curing adhesive. Furthermore, the adhesion mechanism of the adhesive used to form the adhesive layer 2 is not particularly limited, and may be any of chemical reaction type, solvent volatilization type, heat melting type, heat pressure type, and the like.

Specific examples of adhesive components that can be used to form the adhesive layer 2 include polyester-based resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, and copolymerized polyester; Polyurethane adhesive; Epoxy resin; Phenolic resin; Nylon 6, Nylon 66, Nylon 12, polyamide resin such as copolyamide; Polyolefin resin such as polyolefin, carboxylic acid-modified polyolefin, metal-modified polyolefin , polyvinyl acetate resins; cellulose adhesives; (meth)acrylic resins; polyimide resins; polycarbonates; amino resins such as urea resins and melamine resins; system resin and the like. These adhesive components may be used singly or in combination of two or more. Among these adhesive components, polyurethane-based adhesives are preferred.

Moreover, the adhesive layer 2 may contain a coloring agent. Since the adhesive layer 2 contains a coloring agent, the battery packaging material can be colored. Known substances such as pigments and dyes can be used as the colorant. In addition, only one type of colorant may be used, or two or more types may be mixed and used.

For example, specific examples of inorganic pigments preferably include carbon black and titanium oxide. Further, specific examples of organic pigments preferably include azo pigments, phthalocyanine pigments, condensed polycyclic pigments, and the like. Examples of azo pigments include soluble pigments such as Watching Red and Carmine 6C; insoluble azo pigments such as monoazo yellow, disazo yellow, pyrazotone orange, pyrazotone red, and permanent red; Pigments and metal-free phthalocyanine pigments include blue pigments and green pigments, and condensed polycyclic pigments include dioxazine violet, quinacridone violet, and the like. Pearl pigments and fluorescent pigments can also be used as pigments.

Among the coloring agents, carbon black is preferable, for example, in order to make the external appearance of the battery packaging material black.

The average particle size of the pigment is not particularly limited, and is, for example, approximately 0.05 to 5 μm, preferably approximately 0.08 to 2 μm. The average particle size of the pigment is the median size measured with a laser diffraction/scattering particle size distribution analyzer.

The content of the pigment in the adhesive layer 2 is not particularly limited as long as the battery packaging material is colored, and is, for example, about 5 to 60% by mass.

The thickness of the adhesive layer 2 is not particularly limited as long as it functions as an adhesive layer.

[Colored layer 7]
The colored layer 7 is a layer provided between the substrate layer 1 and the adhesive layer 2 as necessary. By providing the colored layer 7, the battery packaging material can be colored.

The colored layer 7 can be formed, for example, by applying ink containing a coloring agent to the surface of the substrate layer 1 . Known substances such as pigments and dyes can be used as the colorant. In addition, only one type of colorant may be used, or two or more types may be mixed and used.

Specific examples of the colorant contained in the colored layer 7 are the same as those exemplified in the section [Adhesive layer 2].

The ink for forming the colored layer 7 is not particularly limited, and known inks can be used. Specific examples of inks include, for example, inks containing colorants, diamines, polyols, and curing agents. As the solvent contained in the ink, a known solvent can be used, for example, toluene.

Examples of the diamine include, but are not limited to, ethylenediamine, dimerdiamine, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, dicyclohexylmethanediamine, 2-hydroxyethylpropylenediamine, and the like. Among them, it is preferable to use one or more diamines selected from the group consisting of ethylenediamine, dimerdiamine, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine and dicyclohexylmethanediamine as the diamine.

A diamine has a faster reaction rate with a curing agent (isocyanate, etc.) than a polyol, and can be cured in a short time. That is, the diamine, together with the polyol, reacts with the curing agent to promote cross-linking curing of the ink.

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

The number average molecular weight of the polyol is preferably in the range of about 1000-8000. When it is 1000 or more, the adhesive strength after curing can be increased, and when it is 8000 or less, the reaction rate with the curing agent can be increased.

Examples of curing agents include, but are not limited to, isocyanate compounds. As the isocyanate compound, for example, various aromatic, aliphatic, and alicyclic isocyanate compounds can be used. Specific examples include toluene diisocyanate (TDI), diphenylmethane diisocyanate, hexamethylene diisocyanate (HDI), isophorone diisocyanate, and the like.

The content of the coloring agent in the colored layer 7 is not particularly limited as long as it can color the battery packaging material, and is, for example, about 5 to 60% by mass. For example, when the colorant is carbon black, the carbon black content is preferably about 20 to 50% by mass. Also, the total content of the diamine, polyol and curing agent is preferably about 40 to 85% by mass. Further, the amount of the curing agent is preferably about 2 to 20 parts by mass with respect to 100 parts by mass of the total amount of the colorant, diamine and polyol.

The thickness of the colored layer 7 (after drying) is preferably about 1 to 4 μm. When the thickness is 1 μm or more, the color tone of the colored layer 7 does not remain transparent, and the color and gloss of the barrier layer 3 can be sufficiently hidden. Further, when the thickness is 4 μm or less, it is possible to sufficiently prevent the colored layer 7 from being partially cracked during molding.

The colored layer 7 can be formed, for example, by applying ink for forming the colored layer 7 to the surface of the substrate layer 1 . Examples of the ink application method include printing methods such as gravure printing, reverse roll coating, and lip roll coating.

[Barrier layer 3]
In the battery packaging material, the barrier layer 3 is a layer that has the function of improving the strength of the battery packaging material and also preventing water vapor, oxygen, light, etc. from entering the battery. The barrier layer 3 is preferably a metal layer, that is, a layer made of metal. Specific examples of the metal forming the barrier layer 3 include aluminum, stainless steel, titanium, and the like, preferably aluminum. The barrier layer 3 can be formed of, for example, a metal foil, a metal vapor deposition film, an inorganic oxide vapor deposition film, a carbon-containing inorganic oxide vapor deposition film, a film provided with these vapor deposition films, or the like. is preferable, and it is more preferable to form it with an aluminum foil or a stainless steel foil.

When the barrier layer 3 is made of aluminum foil, the aluminum foil is made of an aluminum alloy. From the viewpoint of preventing wrinkles and pinholes in the barrier layer 3 during production of the battery packaging material, the barrier layer is made of, for example, annealed aluminum (JIS H4160: 1994 A8021H-O, JIS H4160: 1994 A8079H-O, JIS H4000:2014 A8021P-O, JIS H4000:2014 A8079P-O).

When the barrier layer 3 is made of stainless steel foil, the stainless steel foil is preferably made of austenitic stainless steel. As a result, a battery packaging material having high puncture resistance, excellent electrolytic solution resistance and moldability can be obtained. Specific examples of austenitic stainless steel include SUS304, SUS301, SUS316L, etc. Among these, SUS304 is particularly preferable. In addition, the stainless steel foil is particularly cold-rolled to improve extensibility and formability. Further, after cold rolling, heat treatment and annealing are performed to improve the balance between the flow direction and the width direction and improve the formability. Moreover, in order to stabilize the effect of chemical conversion treatment, which will be described later, it is important to include a surface cleaning step after the rolling treatment or after the heat treatment. Examples of the cleaning method include cleaning using an alkali or acid, alkaline electrolytic degreasing cleaning, and the like. Moreover, it is also possible to use ultrasonic treatment, plasma treatment, etc. together. Alkaline degreasing and alkaline electrolytic degreasing are preferred. As a result, the surface wettability is improved, the chemical conversion treatment can be made uniform, and the content resistance is stabilized.

The thickness of the barrier layer 3 is not particularly limited as long as it functions as a barrier layer against water vapor. .

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

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

In addition, as a chemical conversion treatment method for imparting corrosion resistance to the barrier layer 3, fine particles of metal oxides such as aluminum oxide, titanium oxide, cerium oxide, and tin oxide, and barium sulfate are dispersed in phosphoric acid. A method of forming a corrosion-resistant layer on the surface of the barrier layer 3 by performing a baking treatment at 150° C. or higher can be used. A resin layer obtained by cross-linking a cationic polymer with a cross-linking agent may be further formed on the corrosion-resistant layer. Examples of the cationic polymer include polyethyleneimine, an ionic polymer complex composed of a polymer containing polyethyleneimine and carboxylic acid, a primary amine-grafted acrylic resin obtained by graft-polymerizing a primary amine to an acrylic backbone, and polyallylamine. or derivatives thereof, aminophenol and the like. As these cationic polymers, only one type may be used, or two or more types may be used in combination. Examples of cross-linking agents include compounds having at least one functional group selected from the group consisting of isocyanate groups, glycidyl groups, carboxyl groups, and oxazoline groups, and silane coupling agents. As these cross-linking agents, only one type may be used, or two or more types may be used in combination.

In addition, as a chemical conversion treatment method for imparting corrosion resistance to the barrier layer 3, fine particles of metal oxides such as aluminum oxide, titanium oxide, cerium oxide, and tin oxide, and barium sulfate are dispersed in phosphoric acid. A method of forming an acid-resistant film on the surface of the barrier layer 3 by performing a baking treatment at 150° C. or higher can be mentioned. A resin layer obtained by cross-linking a cationic polymer with a cross-linking agent may be further formed on the acid-resistant film. Examples of the cationic polymer include polyethyleneimine, an ionic polymer complex composed of a polymer containing polyethyleneimine and carboxylic acid, a primary amine-grafted acrylic resin obtained by graft-polymerizing a primary amine to an acrylic backbone, and polyallylamine. or derivatives thereof, aminophenol and the like. As these cationic polymers, only one type may be used, or two or more types may be used in combination. Examples of cross-linking agents include compounds having at least one functional group selected from the group consisting of isocyanate groups, glycidyl groups, carboxyl groups, and oxazoline groups, and silane coupling agents. As these cross-linking agents, only one type may be used, or two or more types may be used in combination.

As a specific method for providing an acid-resistant film, for example, at least the inner layer side surface of an aluminum foil is first subjected to an alkali immersion method, an electrolytic cleaning method, an acid cleaning method, an electrolytic acid cleaning method, Perform degreasing treatment by a well-known treatment method such as an acid activation method, and then apply metal phosphates such as chromium phosphate, titanium phosphate, zirconium phosphate, and zinc phosphate, and these metals to the degreased surface. A treatment liquid (aqueous solution) mainly composed of a mixture of salts, or a treatment liquid (aqueous solution) mainly composed of a non-metallic phosphate and a mixture of these non-metallic salts, or these and an acrylic resin or An acid-resistant film is formed by applying a treatment liquid (aqueous solution) consisting of a mixture of water-based synthetic resins such as phenolic resins and urethane-based resins using well-known coating methods such as roll coating, gravure printing, and dipping. can be formed. For example, when treated with a chromium phosphate-based treatment solution, it becomes an acid-resistant film made of chromium phosphate, aluminum phosphate, aluminum oxide, aluminum hydroxide, aluminum fluoride, etc., and treated with a zinc phosphate-based treatment solution. In this case, an acid-resistant film composed of zinc phosphate hydrate, aluminum phosphate, aluminum oxide, aluminum hydroxide, aluminum fluoride, or the like is formed.

Further, as other specific examples of the method for providing the acid-resistant film, for example, at least the inner layer side surface of the aluminum foil is first subjected to an alkali immersion method, an electrolytic cleaning method, an acid cleaning method, an electrolytic acid cleaning method, an acid activated An acid-resistant film can be formed by performing a degreasing treatment by a well-known treatment method such as a degreasing method, and then subjecting the degreased surface to a well-known anodizing treatment.

Other examples of the acid-resistant coating include phosphate-based and chromic acid-based coatings. Phosphate type includes zinc phosphate, iron phosphate, manganese phosphate, calcium phosphate, chromium phosphate and the like, and chromic acid type includes chromium chromate and the like.

Further, as another example of the acid-resistant film, by forming an acid-resistant film of phosphate, chromate, fluoride, triazinethiol compound, or the like, it is possible to improve the adhesion between the aluminum and the base layer during embossing. Prevents delamination, prevents dissolution and corrosion of the aluminum surface, especially dissolution and corrosion of aluminum oxide present on the aluminum surface, and adheres to the aluminum surface due to hydrogen fluoride generated by the reaction between the electrolyte and moisture. It exhibits the effect of improving wettability, preventing delamination between the base material layer and aluminum during heat sealing, and preventing delamination between the base material layer and aluminum during press molding in the embossed type. Among the substances that form an acid-resistant film, an aqueous solution composed of three components, phenolic resin, chromium (III) fluoride compound, and phosphoric acid, is applied to the surface of aluminum, followed by dry baking.

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

Further, the anionic polymer is preferably poly(meth)acrylic acid or a salt thereof, or a copolymer containing (meth)acrylic acid or a salt thereof as a main component. Moreover, the cross-linking agent is preferably at least one selected from the group consisting of a compound having a functional group such as an isocyanate group, a glycidyl group, a carboxyl group, or an oxazoline group, and a silane coupling agent.

Further, the phosphoric acid or phosphate is preferably condensed phosphoric acid or condensed phosphate.

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

Specific examples of acid-resistant coatings include those containing at least one of phosphates, chromates, fluorides, and triazinethiols. An acid-resistant film containing a cerium compound is also preferred. As the cerium compound, cerium oxide is preferred.

Further, specific examples of acid-resistant coatings include phosphate-based coatings, chromate-based coatings, fluoride-based coatings, and triazinethiol compound coatings. The acid-resistant coating may be one of these, or may be a combination of multiple types. Furthermore, as the acid-resistant film, after degreasing the chemically treated surface of the aluminum foil, It may be formed of a different treatment liquid.

The composition of the acid-resistant coating can be analyzed using, for example, time-of-flight secondary ion mass spectrometry. By analysis of the composition of the acid-resistant coating using time-of-flight secondary ion mass spectrometry, for example, peaks derived from at least one of Ce ⁺ and Cr ⁺ are detected.

It is preferable that the surface of the aluminum foil is provided with an acid-resistant film containing at least one element selected from the group consisting of phosphorus, chromium and cerium. X-ray photoelectron spectroscopy is used to confirm that at least one element selected from the group consisting of phosphorus, chromium and cerium is contained in the acid-resistant coating on the surface of the aluminum foil of the battery packaging material. be able to. Specifically, first, in the battery packaging material, the heat-fusible resin layer, the adhesive layer, and the like laminated on the aluminum foil are physically peeled off. Next, the aluminum foil is placed in an electric furnace, and organic components present on the surface of the aluminum foil are removed at about 300° C. for about 30 minutes. After that, the inclusion of these elements is confirmed using X-ray photoelectron spectroscopy of the surface of the aluminum foil.

The amount of the acid-resistant film formed on the surface of the barrier layer ³ in the chemical conversion treatment is not particularly limited. About 0.5 to 50 mg, preferably about 1.0 to 40 mg, in terms of phosphorus compound, about 0.5 to 50 mg, preferably about 1.0 to 40 mg in terms of phosphorus, and aminated phenol polymer is 1.0 It is desired to be contained in a ratio of about 200 mg, preferably about 5.0 to 150 mg.

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

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

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

The resin component used for the heat-sealable resin layer 4 is not particularly limited as long as it is heat-sealable. Examples include polyolefin, cyclic polyolefin, carboxylic acid-modified polyolefin, and carboxylic acid-modified cyclic polyolefin. be done. That is, the resin forming the heat-fusible resin layer 4 may or may not contain a polyolefin skeleton, and preferably contains a polyolefin skeleton. Whether the resin constituting the heat-fusible resin layer 4 contains a polyolefin skeleton can be analyzed by, for example, infrared spectroscopy, gas chromatography mass spectrometry, or the like, and the analysis method is not particularly limited. For example, when maleic anhydride-modified polyolefin is measured by infrared spectroscopy, peaks derived from maleic anhydride are detected near wavenumbers of 1760 cm ⁻¹ and 1780 cm ⁻¹ . However, if the degree of acid denaturation is low, the peak may be too small to be detected. In that case, it can be analyzed by nuclear magnetic resonance spectroscopy.

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

The cyclic polyolefin is a copolymer of an olefin and a cyclic monomer. Examples of olefins that are constituent monomers of the cyclic polyolefin include ethylene, propylene, 4-methyl-1-pentene, butadiene, and isoprene. be done. Examples of cyclic monomers constituting the cyclic polyolefin include cyclic alkenes such as norbornene; specific examples thereof include cyclic dienes such as cyclopentadiene, dicyclopentadiene, cyclohexadiene and norbornadiene. Styrene is also included as a constituent monomer. Among these polyolefins, cyclic alkenes are preferred, and norbornene is more preferred.

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

The carboxylic acid-modified cyclic polyolefin is obtained by copolymerizing a part of the monomers constituting the cyclic polyolefin with α,β-unsaturated carboxylic acid or its anhydride, or by copolymerizing α,β with respect to the cyclic polyolefin. - Polymers obtained by block or graft polymerization of unsaturated carboxylic acids or their anhydrides. The carboxylic acid-modified cyclic polyolefin is the same as described above. The carboxylic acid used for modification is the same as those used for modifying the carboxylic acid-modified polyolefin.

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

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

The thickness of the heat-fusible resin layer 4 can be selected as appropriate, and is about 8 to 50 μm, preferably about 10 to 40 μm.

Moreover, the heat-fusible resin layer 4 may contain a lubricant or the like as necessary. When the heat-fusible resin layer 4 contains a lubricant, the moldability of the battery packaging material can be enhanced. The lubricant is not particularly limited, and known lubricants can be used. Lubricants may be used singly or in combination of two or more. The content of the lubricant in the heat-fusible resin layer 4 is not particularly limited, and is preferably about 0.01 to 0.20% by mass, more About 0.05 to 0.15% by mass is preferable.

[Adhesion layer 5]
In the battery packaging material of the present invention, the adhesive layer 5 is a layer optionally provided between the barrier layer 3 and the heat-fusible resin layer 4 in order to firmly bond them.

The adhesive layer 5 is made of a resin capable of bonding the barrier layer 3 and the heat-fusible resin layer 4 together. As the resin used to form the adhesive layer 5, the same adhesives as those exemplified for the adhesive layer 2 can be used in terms of the adhesive mechanism, the types of adhesive components, and the like. As the resin used to form the adhesive layer 5, polyolefin-based resins such as polyolefins, cyclic polyolefins, carboxylic acid-modified polyolefins, and carboxylic acid-modified cyclic polyolefins exemplified for the heat-sealable resin layer 4 can also be used. . From the viewpoint of excellent adhesion between the barrier layer 3 and the heat-fusible resin layer 4, the polyolefin is preferably carboxylic acid-modified polyolefin, and particularly preferably carboxylic acid-modified polypropylene. That is, the resin forming the adhesive layer 5 may or may not contain a polyolefin skeleton, and preferably contains a polyolefin skeleton. Whether or not the resin constituting the adhesive layer 5 contains a polyolefin skeleton can be analyzed by, for example, infrared spectroscopy, gas chromatography mass spectrometry, or the like, and the analysis method is not particularly limited. For example, when maleic anhydride-modified polyolefin is measured by infrared spectroscopy, peaks derived from maleic anhydride are detected near wavenumbers of 1760 cm ⁻¹ and 1780 cm ⁻¹ . However, if the degree of acid denaturation is low, the peak may be too small to be detected. In that case, it can be analyzed by nuclear magnetic resonance spectroscopy.

Furthermore, from the viewpoint of making the battery packaging material excellent in moldability while reducing the thickness of the battery packaging material, the adhesive layer 5 should be a cured product of a resin composition containing an acid-modified polyolefin and a curing agent. is also preferred. As the acid-modified polyolefin, the same carboxylic acid-modified polyolefin and carboxylic acid-modified cyclic polyolefin exemplified for the heat-sealable resin layer 4 can be preferably exemplified.

Moreover, the curing agent is not particularly limited as long as it cures the acid-modified polyolefin. Examples of curing agents include epoxy-based curing agents, polyfunctional isocyanate-based curing agents, carbodiimide-based curing agents, and oxazoline-based curing agents.

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

The polyfunctional isocyanate-based curing agent 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 isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymers and nurates thereof, and mixtures thereof. and copolymers with other polymers.

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

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

From the viewpoint of enhancing the adhesion between the barrier layer 3 and the heat-fusible resin layer 4 by the adhesive layer 5, the curing agent may be composed of two or more kinds of compounds.

The content of the curing agent in the resin composition forming the adhesive layer 5 is preferably in the range of about 0.1 to 50% by mass, more preferably in the range of about 0.1 to 30% by mass. More preferably, it is in the range of about 0.1 to 10% by mass.

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

[Surface coating layer 6]
In the battery packaging material of the present invention, for the purpose of improving design, electrolyte resistance, scratch resistance, moldability, etc., on the substrate layer 1 (barrier layer of the substrate layer 1) 3), a surface coating layer 6 may be provided, if necessary. The surface coating layer 6 is the outermost layer when the battery is assembled.

The surface coating layer 6 can be formed from a resin composition. Components contained in the resin composition include resin components, curing accelerators, and additives (such as fillers), as described later.

The resin component contained in the resin composition preferably contains a thermosetting resin. Any thermosetting resin may be used as long as it polymerizes when heated to form a polymer network structure and hardens. Specific examples of thermosetting resins include polyvinylidene chloride, polyester resins, epoxy resins, amino resins (melamine resins, benzoguanamine resins, etc.), acrylic resins, urethane resins, phenolic resins, unsaturated polyester resins, alkyd resins, and the like. is mentioned.

Among these thermosetting resins, urethane resins and epoxy resins are preferred from the viewpoint of shortening the curing time and improving moldability and chemical resistance. Examples include liquid-curing epoxy resins, and particularly preferably two-component curing epoxy resins.

A specific example of a two-component curable urethane resin is a combination of a polyol compound (main agent) and an isocyanate compound (curing agent). A specific example of a two-component curable epoxy resin is an epoxy resin (main agent). and an acid anhydride, an amine compound, or an amino resin (curing agent). As the two-pack curable urethane resin, a polyfunctional urethane (meth)acrylate composed of a combination of a polyfunctional (meth)acrylate having active hydrogen (main agent) and a polyisocyanate (curing agent) is also preferable.

The polyol compound used as the main ingredient in the two-pack curable urethane resin is not particularly limited, but examples thereof include polyester polyols, polyester polyurethane polyols, polyether polyols, and polyether polyurethane polyols. These polyol compounds may be used singly or in combination of two or more.

In addition, in the two-pack curable urethane resin, the isocyanate compound used as a curing agent is not particularly limited. , its burette modification, and the like. Specific examples of polyisocyanates include diphenylmethane diisocyanate (MDI), polyphenylmethane diisocyanate (polymeric MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), bis(4-isocyanatocyclohexyl)methane (H12MDI), aromatic diisocyanates such as isophorone diisocyanate (IPDI), 1,5-naphthalene diisocyanate (1,5-NDI), 3,3′-dimethyl-4,4′-diphenylene diisocyanate (TODI), xylene diisocyanate (XDI); aliphatic diisocyanates such as tramethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate and isophorone diisocyanate; alicyclic diisocyanates such as 4,4′-methylenebis(cyclohexyl isocyanate) and isophorone diisocyanate; 5-NDI) and other polycyclic aromatic diisocyanates. Specific examples of adducts include those obtained by adding trimethylolpropane, glycol, or the like to the above polyisocyanate. These isocyanate compounds may be used singly or in combination of two or more.

These thermosetting resins may also be crosslinkable elastomers. A crosslinkable elastomer is a thermosetting resin that can impart soft segments to a cured product. For example, among crosslinkable elastomers, in the case of a two-pack curable urethane resin or a two-pack curable epoxy resin, it is sufficient that the main agent has a structure capable of imparting soft segments. The crosslinkable elastomer can be used as a part of the thermosetting resin used to form the layer constituting the surface coating layer 6 in order to provide the layer constituting the surface coating layer 6 with a desired hardness. can.

These thermosetting resins may be used singly or in combination of two or more. Moreover, the surface coating layer 6 may be formed of a plurality of layers. When the surface coating layer 6 is formed of a plurality of layers, the thermosetting resin used in each layer may be the same or different, and the type of thermosetting resin depends on the function to be provided in each layer. and physical properties. For example, among the layers constituting the surface coating layer 6, the layer forming the outermost layer (the outermost layer located on the opposite side to the base material layer 1) has a polycyclic A thermosetting resin having an aromatic skeleton and/or a heterocyclic skeleton is preferably used. Specific examples of thermosetting resins having a polycyclic aromatic skeleton include epoxy resins having a polycyclic aromatic skeleton and urethane resins having a polycyclic aromatic skeleton. Further, specific examples of thermosetting resins having a heterocyclic skeleton include amino resins such as melamine resins and benzoguanamine resins. These thermosetting resins having a polycyclic aromatic skeleton and/or heterocyclic skeleton may be either one-component curing type or two-component curing type.

More specifically, the epoxy resin having a polycyclic aromatic skeleton includes a reaction product of dihydroxynaphthalene and epihalohydrin; a reaction product of a condensate of naphthalene and an aldehyde with epihalohydrin; a reaction product of a condensate of mono- or dihydroxynaphthalene with xylylene glycols and epihalohydrin; an adduct of a mono- or dihydroxynaphthalene and a diene compound; reaction products with epihalohydrin; reaction products of epihalohydrin with polynaphthols in which naphthols are directly coupled;

More specifically, the urethane resin having a polycyclic aromatic skeleton includes a reaction product of a polyol compound and an isocyanate compound having a polycyclic aromatic skeleton.

(Curing accelerator)
The resin composition forming the surface coating layer 6 may further contain a curing accelerator in addition to the above resin components. By coexisting a curing accelerator together with the thermosetting resin, the surface coating layer 6 can be cured in a short time without requiring aging under high-temperature conditions during production, and a layer having a specific hardness can be formed. .

Here, the "curing accelerator" is a substance that does not form a crosslinked structure by itself, but promotes the crosslinking reaction of the thermosetting resin. is also a substance that may form a crosslinked structure.

The type of curing accelerator is appropriately selected depending on the thermosetting resin to be used so as to satisfy the hardness described above. Thiazolium salts, tertiary amine compounds and the like can be mentioned.

Examples of amidine compounds include, but are not limited to, imidazole compounds, 1,8-diazabicyclo[5.4.0]undec-7ene (DBU), 1,5-diazabicyclo[4.3.0]none-5- ene (DBN), guanidine compounds, and the like. Specific examples of imidazole compounds include 2-methylimidazole, 2-ethylimidazole, 2-undecylimidazole, 2,4-dimethylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 1,2- Diethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-benzyl-2 -methylimidazole, 2,4-diamino-6-[2'-methylimidazolyl-(1)']-ethyl-S-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl -(1)']-ethyl-S-triazine, 2,4-diamino-6-[2'-undecylimidazolyl]-ethyl-S-triazine, 2,4-diamino-6-[2'-methylimidazolyl -(1)′]-ethyl-S-triazineisocyanuric oxidized adduct, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-aryl-4, and 5-diphenylimidazole. These amidine compounds may be used singly or in combination of two or more.

The carbodiimide compound is not particularly limited, but examples include N,N'-dicyclohexylcarbodiimide, N,N'-diisopropylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, N-[3-(dimethylamino ) propyl]-N'-ethylcarbodiimide, N-[3-(dimethylamino)propyl]-N'-ethylcarbodiimide methiodide, N-tert-butyl-N'-ethylcarbodiimide, N-cyclohexyl-N'- (2-morpholinoethyl)carbodiimide meso-p-toluenesulfonate, N,N'-di-tert-butylcarbodiimide, N,N'-di-p-tolylcarbodiimide and the like. These carbodiimide compounds may be used singly or in combination of two or more.

The ketimine compound is not particularly limited as long as it has a ketimine bond (N=C), and includes, for example, a ketimine compound obtained by reacting a ketone with an amine. Specific examples of ketones include methyl ethyl ketone, methyl isopropyl ketone, methyl tertiary butyl ketone, methyl cyclohexyl ketone, diethyl ketone, ethyl propyl ketone, ethyl butyl ketone, dipropyl ketone, dibutyl ketone, and diisobutyl ketone. . Further, specific examples of amines include aromatic polyamines such as o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, m-xylylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, and diaminodiethyldiphenylmethane; Ethylenediamine, propylenediamine, butylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexamethylenediamine, trimethylhexamethylenediamine, 1,2-propanediamine, iminobispropylamine, methyliminobispropylamine, etc. aliphatic polyamines; N-aminoethylpiperazine, 3-butoxyisopropylamine and other monoamines and polyether backbone diamines having an ether bond in the main chain; isophoronediamine, 1,3-bisaminomethylcyclohexane, 1-cyclohexylamino- Alicyclic polyamines such as 3-aminopropane and 3-aminomethyl-3,3,5-trimethylcyclohexylamine: diamines having a norbornane skeleton; polyamidoamines having amino groups at the ends of polyamide molecules; 2,5-dimethyl-2 ,5-hexamethylenediamine, menzenediamine, 1,4-bis(2-amino-2-methylpropyl)piperazine and the like. These ketimine compounds may be used singly or in combination of two or more.

Although the hydrazine compound is not particularly limited, examples thereof include dihydrazide dipicate and dihydrazide isophthalate. These hydrazine compounds may be used singly or in combination of two or more.

The sulfonium salt is not particularly limited, but examples include 4-acetophenyldimethylsulfonium hexafluoroantimonate, 4-acetophenyldimethylsulfonium hexafluoroarsenate, dimethyl-4-(benzyloxycarbonyloxy)phenylsulfonium hexafluoroantimonate, Alkylsulfonium salts such as dimethyl-4-(benzoyloxy)phenylsulfonium hexafluoroantimonate, dimethyl-4-(benzoyloxy)phenylsulfonium hexafluoroarsenate; benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 4- Acetoxyphenylbenzylmethylsulfonium hexafluoroantimonate, benzyl-4-methoxyphenylmethylsulfonium hexafluoroantimonate, benzyl-3-chloro-4-hydroxyphenylmethylsulfonium hexafluoroarsenate, 4-methoxybenzyl-4-hydroxyphenylmethyl benzylsulfonium salts such as sulfonium hexafluorophosphate; dibenzyl-4-hydroxyphenylsulfonium hexafluoroantimonate, dibenzyl-4-hydroxyphenylsulfonium hexafluorophosphate, dibenzyl-4-methoxyphenylsulfonium hexafluoroantimonate, benzyl-4-methoxy Dibenzylsulfonium salts such as benzyl-4-hydroxyphenylsulfonium hexafluorophosphate; p-chlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, p-nitrobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 3 ,5-dichlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, o-chlorobenzyl-3-chloro-4-hydroxyphenylmethylsulfonium hexafluoroantimonate and other substituted benzylsulfonium salts. These sulfonium salts may be used singly or in combination of two or more.

The benzothiazolium salt is not particularly limited, but examples include 3-benzylbenzothiazolium hexafluoroantimonate, 3-benzylbenzothiazolium hexafluorophosphate, 3-benzylbenzothiazolium tetrafluoroborate, 3- Benzyl benzos such as (p-methoxybenzyl) benzothiazolium hexafluoroantimonate, 3-benzyl-2-methylthiobenzothiazolium hexafluoroantimonate, 3-benzyl-5-chlorobenzothiazolium hexafluoroantimonate thiazolium salts. These benzothiazolium salts may be used singly or in combination of two or more.

The tertiary amine compound is not particularly limited. aromatic tertiary amines such as dimethylaniline; heterocyclic tertiary amines such as isoquinoline, pyridine, collidine and beta-picoline; These tertiary amine compounds may be used singly or in combination of two or more.

A preferred example of the curing accelerator is one that functions as a thermal acid generator. A thermal acid generator is a substance that generates acid by heating and functions as a curing accelerator. Among the curing accelerators described above, specific examples of those that can function as thermal acid generators include sulfonium salts and benzothiazolium salts.

Further, another preferred example of the curing accelerator is a thermal latent agent that is activated under predetermined heating conditions (for example, 80 to 200° C., preferably 100 to 160° C.) to promote the cross-linking reaction of the thermosetting resin. What is provided is mentioned. Among the curing accelerators described above, specific examples of heat-latent substances include epoxy adducts in which an epoxy compound is added to an amidine compound, a hydrazine compound, a tertiary amine compound, or the like.

Furthermore, another preferred example of the curing accelerator is a curing accelerator that does not function as a curing agent in a sealed state, that is, in a moisture-blocked state, but is hydrolyzed under conditions in which moisture is present after the sealed state is opened. Those with functional hydrolytic potential are included. Among the curing accelerators mentioned above, specific examples of hydrolytically latent substances include epoxy adducts in which an epoxy compound is added to an amidine compound, a hydrazine compound, a tertiary amine compound, or the like.

These curing accelerators may be used singly or in combination of two or more. Among these curing accelerators, amidine compounds and sulfonium salts are preferred, and amidine compounds are more preferred.

These curing accelerators may be used singly or in combination of two or more in the surface coating layer 6 . Further, when the surface coating layer 6 is formed of a plurality of layers, the curing accelerator used between the layers constituting the surface coating layer 6 may be the same or different. The type may be appropriately selected according to the functions, physical properties, etc. to be provided in each layer.

When using a curing accelerator, the content of the curing accelerator in the resin composition used to form the surface coating layer 6 is appropriately set according to the type of thermosetting resin used, the type of curing accelerator, etc. However, for example, the total amount of the curing accelerator is about 0.01 to 6 parts by mass, preferably about 0.05 to 5 parts by mass, more preferably 0.1 to 100 parts by mass with respect to 100 parts by mass of the thermosetting resin. About 2 parts by mass can be mentioned.

The surface coating layer 6 preferably contains a filler as an additive. That is, the surface coating layer 6 is preferably made of a resin composition containing a filler. When the surface coating layer 6 contains a filler, the surface of the surface coating layer 6 can be formed with an uneven shape, and the battery packaging material can be given a matte feel. Specific examples of fillers include inorganic fillers such as titanium oxide, silica, talc, clay, heavy calcium carbonate, light calcium carbonate, barium sulfate, calcium silicate, synthetic silicates, aluminum hydroxide, and silicic acid fine powder. mentioned. Only one type of filler may be used, or two or more types may be mixed and used.

Among inorganic fillers, inorganic fillers made of silica or precipitated barium sulfate are preferred because they are easy to handle and readily available. Precipitated barium sulfate refers to barium sulfate produced using a chemical reaction, and is characterized by being able to control the particle size.

The content of the filler in the surface coating layer 6 is preferably about 2.0 to 8.7% by mass when the filler is silica having an average particle diameter of about 1.0 to 3.0 μm. For example, when the filler is sedimentary barium sulfate having an average particle size of less than 1.5 μm, the content is preferably about 13.0 to 40.0% by mass. The filler content is the content of the filler in the surface coating layer 6, and is the content after the solvent volatilizes from the aforementioned resin composition for forming the surface coating layer 6 containing the filler. The average particle size of the filler is the median size measured with a laser diffraction/scattering particle size distribution analyzer.

The surface coating layer 6 may contain at least one of a pigment and a dye as an additive. When the surface coating layer 6 contains at least one of a pigment and a dye, whitening during molding can be more effectively suppressed, and abrasion resistance can be improved. In addition, since the surface coating layer 6 contains at least one of a pigment and a dye, the battery packaging material of the present invention can be given an identifiable property (coloring by at least one of the pigment and the dye), and the battery packaging of the present invention can be obtained. It is possible to impart a matte design to the surface of the material, and to improve heat dissipation by increasing the thermal conductivity of the battery packaging material of the present invention.

The material of the pigment is not particularly limited, and may be either an inorganic pigment or an organic pigment. Specific examples of the inorganic pigments include carbon black, carbon nanotube, graphite, kaolin, magnesium hydroxide, zinc oxide, magnesium oxide, aluminum oxide, neodymium oxide, antimony oxide, cerium oxide, calcium sulfate, lithium carbonate, gold. , aluminum, copper, nickel and the like. Specific examples of organic pigments include azo pigments, polycyclic pigments, lake pigments, and fluorescent pigments. These pigments may be used singly or in combination of two or more.

The shape of the pigment is also not particularly limited, and examples thereof include spherical, fibrous, plate-like, amorphous, and balloon-like shapes. The average particle size of the pigment is not particularly limited, but is preferably about 0.01 to 3 μm, more preferably about 0.05 to 1 μm. The average particle size of the pigment is the median size measured with a laser diffraction/scattering particle size distribution analyzer.

Various surface treatments such as insulation treatment and high dispersibility treatment (resin coating treatment) may be applied to the surface of the pigment, if necessary.

The type of dye is not particularly limited as long as it can be dissolved and dispersed in the resin composition used for forming the surface coating layer 6. Examples include nitro dyes, azo dyes, stilbene dyes, carponium dyes, Examples include quinoline dyes, methine dyes, thiazole dyes, quinimine dyes, anthraquinone dyes, indigoid dyes, and phthalocyanine dyes, preferably azo dyes, carponium dyes, and anthraquinone dyes. These dyes may be used singly or in combination of two or more.

Among these pigments and dyes, from the viewpoint of further improving the heat dissipation properties of the battery packaging material of the present invention, pigments are preferable, inorganic pigments are more preferable, and carbon such as carbon black, carbon nanotubes and graphite is more preferable. Materials, particularly preferably carbon black, may be mentioned.

When the surface coating layer 6 has a multi-layer structure composed of two or more layers, the pigment and/or dye should be contained in any one of these two or more layers. It may be contained in one layer, or may be contained in two or more layers. After molding the battery packaging material of the present invention, the surface coating layer 6 is formed into a multilayer structure composed of two or more layers from the viewpoint of reducing the difference in color tone between the molded portion and the unmolded portion. It is preferable that two or more layers contain pigments and/or dyes, and the surface coating layer 6 has a three-layer structure composed of three layers and all three layers contain pigments and/or dyes. is more preferred.

When pigments and/or dyes are contained in at least one layer constituting the surface coating layer 6, the content of the pigments and/or dyes to be used depends on the type of the pigments and/or dyes used and the battery packaging material of the present invention. It may be appropriately set according to distinguishability, heat dissipation, etc. For example, the total amount of pigment and / or dye is 1 to 30 parts with respect to 100 parts by mass of the resin component contained in the layer containing the pigment and / or dye. Part by mass may be mentioned. From the viewpoint of imparting even better distinguishability, the total amount of the pigment and / or dye is about 3 to 20 parts by mass with respect to 100 parts by mass of the resin component contained in the layer containing the pigment and / or dye. be done. In addition, from the viewpoint of suppressing the deterioration of moldability caused by pigments and / or dyes, along with even better distinguishability, with respect to 100 parts by mass of the resin component contained in the layer containing pigments and / or dyes, The total amount of pigments and/or dyes is about 5 to 15 parts by mass.

The resin composition used for forming the surface coating layer 6 may contain organic fillers, lubricants, Other additives such as solvents, elastomeric resins, etc. may be included.

When the surface coating layer 6 contains an organic filler or a lubricant as an additive, it imparts a slip effect to the surface of the battery packaging material of the present invention. You can improve the quality.

Although the type of organic filler is not particularly limited, examples thereof include high melting point nylon, acrylate resin, crosslinked acryl, crosslinked styrene, crosslinked polyethylene, and benzoguanamine. The shape of the organic filler is also not particularly limited, but examples thereof include spherical, fibrous, plate-like, amorphous, and balloon-like shapes.

Moreover, the lubricant is not particularly limited, and may be, for example, a non-reactive lubricant or a reactive lubricant. In particular, the reactive lubricant is less likely to bleed and lose from the outermost layer that constitutes the surface coating layer 6, and can suppress the occurrence of dusting and set-off during use, and the deterioration of the slip effect over time. Among the lubricants, reactive lubricants are preferably mentioned because of their advantages.

Here, the non-reactive lubricant is, for example, a compound that does not have a functional group that reacts with and chemically bonds with the resin component described above and that can impart slipperiness (slipperiness). A reactive lubricant is a compound that has a functional group that reacts with and chemically bonds with the resin component and that can impart slipperiness (slipperiness).

Specific examples of non-reactive lubricants include amide lubricants, fatty acid amides, metal soaps, hydrophilic silicones, silicone-grafted acrylics, silicone-grafted epoxies, silicone-grafted polyethers, and silicone-grafted lubricants. polyester, block-type silicone acrylic copolymer, polyglycerol-modified silicone, paraffin, and the like. As the amide-based lubricant, for example, the amide-based lubricant described above can be used. These non-reactive lubricants may be used singly or in combination of two or more.

In addition, in the reactive lubricant, the type of functional group is appropriately set according to the type of resin component used. A vinyl group, a (meth)acryloyl group, and the like can be mentioned. In the reactive lubricant, the number of functional groups per molecule is not particularly limited, but may be, for example, 1 to 3, preferably 1 or 2.

Specific examples of reactive lubricants include modified silicones having the above functional groups; modified fluororesins having the above functional groups; compounds into which the functional groups are introduced; metal soaps into which the functional groups are introduced; and paraffins into which the functional groups are introduced. These reactive lubricants may be used singly or in combination of two or more. Among these reactive lubricants, modified silicones having the above functional groups, modified fluororesins having the above functional groups, and silicone modified resins having the above functional groups are preferred. Specific examples of the modified silicone include modified silicone obtained by block polymerization of a polymer having the functional group, such as modified silicone obtained by block polymerization of acrylic resin; modified silicone obtained by graft polymerization of acrylate; Examples thereof include modified silicone obtained by graft polymerization of a monomer having the functional group. Specific examples of the modified fluororesin include, for example, a modified fluororesin obtained by graft polymerization of a monomer having the functional group, such as a fluororesin obtained by graft polymerization of acrylate; A fluororesin obtained by block polymerization of a polymer having the above-mentioned functional groups, such as a fluororesin, can be used. As the silicone-modified resin, specifically, silicone having the functional group and graft-polymerized with silicone, such as a silicone-modified acrylic resin in which silicone is graft-polymerized to the acrylic resin having the functional group. Examples include modified resins. Among these, as a particularly preferable reactive lubricant, a modified silicone in which the monomer or polymer having the functional group is polymerized at one end of the silicone; the monomer or polymer having the functional group is a fluororesin A modified fluororesin polymerized at one end of is mentioned. As such modified silicones and modified fluororesins, for example, "Modiper (registered trademark) F FS series" (manufactured by NOF Corporation), "Symac (registered trademark) series" (manufactured by Toagosei Co., Ltd.), etc. are commercially available. and these commercially available products can also be used.

When the resin composition used for forming the outermost layer in the surface coating layer 6 contains a lubricant, the content is not particularly limited. The total amount of lubricant is about 1 to 12 parts by mass, preferably about 3 to 10 parts by mass, more preferably about 5 to 8 parts by mass.

Other specific examples of additives include montmorilloid, montmorillonite, synthetic mica, hydrotalcite, zeolite, calcium benzoate, calcium oxalate, magnesium stearate, gold, aluminum, copper and nickel.

A method for forming the surface coating layer 6 is not particularly limited, but an example thereof includes a method of applying a resin composition for forming the surface coating layer 6 onto one surface of the substrate layer 1 . When an additive is added, the additive may be added to the resin composition, mixed, and then applied.

The thickness of the surface coating layer 6 is not particularly limited as long as it exhibits the above functions as the surface coating layer 6, but is, for example, approximately 0.5 to 10 μm, preferably approximately 1 to 5 μm.

3. Method for Producing Battery Packaging Material The method for producing the battery packaging material of the present invention is not particularly limited as long as a laminate obtained by laminating each layer having a predetermined composition can be obtained. An example of the method for producing the battery packaging material of the present invention is as follows. First, a layered body (hereinafter also referred to as "layered body A") is formed by laminating a substrate layer 1, an adhesive layer 2, and a barrier layer 3 in this order. Specifically, the laminate A is formed by applying an adhesive used for forming the adhesive layer 2 on the base material layer 1 or on the barrier layer 3 whose surface is chemically treated as necessary by a gravure coating method. , a dry lamination method in which the barrier layer 3 or the substrate layer 1 is laminated and the adhesive layer 2 is cured after coating and drying by a coating method such as a roll coating method. At this time, aging may be performed as necessary. When the colored layer 7 is provided between the base material layer 1 and the adhesive layer 2, the ink for forming the colored layer 7 is applied to the surface of one side of the base material layer 1 in advance. and the barrier layer 3 are laminated to obtain a laminated body A.

Next, on the barrier layer 3 of the laminate A, the heat-fusible resin layer 4 is laminated. When the heat-fusible resin layer 4 is directly laminated on the barrier layer 3, the resin component constituting the heat-fusible resin layer 4 is applied onto the barrier layer 3 of the laminate A by a gravure coating method or a roll coating method. It may be applied by a method such as the following. Further, when the adhesive layer 5 is provided between the barrier layer 3 and the heat-fusible resin layer 4, for example, (1) the adhesive layer 5 and the heat-fusible resin layer are placed on the barrier layer 3 of the laminate A. 4 (co-extrusion lamination method); (3) a method of extruding or solution-coating an adhesive for forming an adhesive layer 5 on the barrier layer 3 of the laminate A, followed by drying and baking at a high temperature; (4) The barrier layer 3 of the laminate A and the barrier layer 3 of the laminated body A, which is laminated in advance in a sheet form A method of laminating the laminate A and the heat-fusible resin layer 4 via the adhesive layer 5 while pouring the melted adhesive layer 5 between the formed heat-fusible resin layer 4 (sandwich lamination method). etc.

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

Surface coating layer 6/base layer 1/adhesive layer 2 provided as required/barrier layer 3 whose surface is chemically treated as required/as required as described above In order to strengthen the adhesiveness of the adhesive layer 2 or the adhesive layer 5, a hot roll contact type , hot air, near-infrared, or far-infrared heat treatment. Conditions for such heat treatment include, for example, about 150 to 250° C. for about 1 to 5 minutes.

In the battery packaging material of the present invention, each layer constituting the laminate improves or stabilizes film formability, lamination processing, final product secondary processing (pouching, embossing) aptitude, etc. as necessary. For this purpose, surface activation treatment such as corona treatment, blasting treatment, oxidation treatment, and ozone treatment may be applied.

4. Use of Battery Packaging Material The battery packaging material of the present invention is used as a package for hermetically housing battery elements such as a positive electrode, a negative electrode and an electrolyte. That is, a battery can be made by housing a battery element comprising at least a positive electrode, a negative electrode, and an electrolyte in a package formed of the battery packaging material of the present invention.

Specifically, a battery element comprising at least a positive electrode, a negative electrode, and an electrolyte is wrapped in the battery packaging material of the present invention in a state in which metal terminals connected to the positive electrode and the negative electrode protrude outward. The peripheral edge of the element is coated so as to form a flange portion (region where the heat-fusible resin layers contact each other), and the heat-fusible resin layers of the flange portion are heat-sealed to seal the battery. A battery using the packaging material for a battery is provided. When a battery element is housed in a package formed of the battery packaging material of the present invention, the heat-sealable resin portion of the battery packaging material of the present invention should face the inside (the surface in contact with the battery element). to form a package.

The battery packaging material of the present invention may be used for either primary batteries or secondary batteries, preferably for secondary batteries. The type of secondary battery to which the battery packaging material of the present invention is applied is not particularly limited. Examples include iron storage batteries, nickel/zinc storage batteries, silver oxide/zinc storage batteries, metal-air batteries, polyvalent cation batteries, capacitors, capacitors, and the like. Among these secondary batteries, lithium-ion batteries and lithium-ion polymer batteries can be cited as suitable targets for application of the battery packaging material of the present invention.

EXAMPLES The present invention will be described in detail below with reference to examples and comparative examples. However, the present invention is not limited to the examples.

<Manufacturing of packaging materials for batteries>
Battery packaging materials of Examples 1 to 5 and Comparative Examples 1 to 3 were produced by the following procedure. Table 1 shows the laminate structure of each battery packaging material. In Table 1, SF is a surface coating layer, ON is a biaxially oriented nylon film, DL is an adhesive layer or adhesive layer formed by a dry lamination method, AL is an aluminum foil, PPa is maleic anhydride-modified polypropylene, and PP is random. Polypropylene, CPP, means unstretched polypropylene film. Further, the numerical value attached after each layer means the thickness of the layer. For example, "ON15" means "a biaxially stretched nylon film with a thickness of 15 µm".

Example 1
A barrier layer made of aluminum foil (thickness: 35 μm, JIS H4160: 1994 A8021H-O) subjected to chemical conversion treatment on both sides was formed by a dry lamination method on a biaxially stretched nylon film (thickness: 15 μm) as a base layer. Laminated. Specifically, a two-component urethane adhesive (a polyol compound and an aromatic isocyanate compound) was applied to one surface of the barrier layer to form an adhesive layer (3 μm thick) on the barrier layer. Next, the adhesive layer on the barrier layer and the substrate layer were laminated to prepare a laminate of substrate layer/adhesive layer/barrier layer. In addition, the chemical conversion treatment of the aluminum foil used as the barrier layer was carried out by roll-coating a treatment solution consisting of phenolic resin, chromium fluoride compound, and phosphoric acid so that the coating amount of chromium was 10 mg/m ² (dry mass). It was applied to both sides of an aluminum foil according to the method and baked.

Next, maleic anhydride-modified polypropylene (thickness: 20 μm, placed on the barrier layer side) and random polypropylene (thickness: 15 μm, innermost layer) were co-extruded on the barrier layer of the obtained laminate to form a barrier layer. An adhesive layer/heat-fusible resin layer was laminated on the layer. Next, the resulting laminate is heated at 175° C. for 2 minutes to provide a battery packaging material in which base layer/adhesive layer/barrier layer/adhesive layer/thermal adhesive resin layer are laminated in this order. got

Example 2
In the same manner as in Example 1, a laminate of substrate layer/adhesive layer/barrier layer was produced. Next, a solution (thickness after curing: 2 μm) containing maleic anhydride-modified polypropylene and a curing agent (epoxy-based) was applied onto the barrier layer of the obtained laminate, and an unstretched polypropylene film was further coated thereon. (thickness: 30 μm) to obtain a battery packaging material in which a substrate layer/adhesive layer/barrier layer/adhesive layer/heat-fusible resin layer were laminated in this order.

Example 3
A barrier layer made of aluminum foil (thickness: 35 μm, JIS H4160: 1994 A8021H-O) subjected to chemical conversion treatment on both sides was formed by a dry lamination method on a biaxially stretched nylon film (thickness: 15 μm) as a base layer. Laminated. Specifically, a two-component urethane adhesive (polyol compound and aromatic isocyanate compound) containing carbon black (median diameter 0.191 μm) is applied to one surface of the barrier layer, and the adhesive is applied onto the barrier layer. A layer (thickness 3 μm) was formed. Next, after laminating the adhesive layer on the barrier layer and the substrate layer, an aging treatment was performed to prepare a laminate of substrate layer/adhesive layer (black)/barrier layer. The chemical conversion treatment of the aluminum foil used as the barrier layer was performed in the same manner as in Example 1. The average particle size of carbon black is the median size measured with a laser diffraction/scattering particle size distribution analyzer ("LA-950" manufactured by Horiba, Ltd.).

Next, maleic anhydride-modified polypropylene (thickness: 20 μm, placed on the barrier layer side) and random polypropylene (thickness: 15 μm, innermost layer) were co-extruded on the barrier layer of the obtained laminate to form a barrier layer. An adhesive layer/heat-fusible resin layer was laminated on the layer. Next, the obtained laminate was heated at 175° C. for 2 minutes to obtain a laminate in which the substrate layer/adhesive layer/barrier layer/adhesive layer/heat-fusible resin layer were laminated in this order. . Next, a resin containing precipitated barium sulfate as a filler with an average particle size of 1 μm, erucamide, and an acrylate resin with an average particle size of 2 μm is applied to the surface of the base material layer of the obtained laminate by gravure coating. The composition was coated so as to have a thickness of about 3 μm after drying to form a surface coating layer. Next, by heating the obtained laminate, a battery for a battery in which surface coating layer/base material layer/adhesive layer (black)/barrier layer/adhesive layer/heat-fusible resin layer are laminated in this order Got the packaging material. The average particle size of precipitated barium sulfate is the median size measured with a laser diffraction/scattering particle size distribution analyzer ("LA-950" manufactured by Horiba, Ltd.).

Example 4
A black colored layer was formed by printing a black pigment to a thickness of 1 μm on one surface of a biaxially stretched nylon film (thickness: 15 μm) as a substrate layer. Next, a barrier layer made of aluminum foil (thickness: 35 μm, JIS H4160:1994 A8021H-O) subjected to chemical conversion treatment on both sides was laminated by a dry lamination method on the colored layer side of the base material layer. Specifically, a two-component urethane adhesive (a polyol compound and an aromatic isocyanate compound) was applied to one surface of the barrier layer to form an adhesive layer (3 μm thick) on the barrier layer. Next, after laminating the adhesive layer on the barrier layer and the colored layer side of the substrate layer, aging treatment is performed to laminate the substrate layer/colored layer (black)/adhesive layer/barrier layer. made the body. The chemical conversion treatment of the aluminum foil used as the barrier layer was performed in the same manner as in Example 1.

Next, a two-part urethane adhesive (a polyol compound and an aromatic isocyanate compound) was applied onto the barrier layer of the obtained laminate to form an adhesive layer (3 μm thick) on the barrier layer. Further, an unstretched polypropylene film (thickness: 30 μm) was laminated on the adhesive layer. Next, aging treatment was performed by heating the obtained laminate. Next, a surface coating layer was formed by coating the surface of the substrate layer of the obtained laminate with a resin composition containing a filler so as to have a thickness of 3 μm. Next, the obtained laminate is heated and aged to obtain a surface coating layer/base layer/colored layer (black)/adhesive layer/barrier layer/adhesive layer/heat-fusible resin layer. were laminated in this order to obtain a battery packaging material.

Example 5
A barrier layer made of aluminum foil (thickness: 30 μm, JIS H4160: 1994 A8021H-O) subjected to chemical conversion treatment on both sides was formed by a dry lamination method on a biaxially stretched nylon film (thickness: 15 μm) as a base layer. Laminated. Specifically, a two-component urethane adhesive (a polyol compound and an aromatic isocyanate compound) was applied to one surface of the barrier layer to form an adhesive layer (3 μm thick) on the barrier layer. Next, the adhesive layer on the barrier layer and the substrate layer were laminated to prepare a laminate of substrate layer/adhesive layer/barrier layer. The chemical conversion treatment of the aluminum foil used as the barrier layer was performed in the same manner as in Example 1.

Next, maleic anhydride-modified polypropylene (thickness: 14 μm, placed on the barrier layer side) and random polypropylene (thickness: 10 μm, innermost layer) were co-extruded on the barrier layer of the obtained laminate to form a barrier layer. An adhesive layer/heat-fusible resin layer was laminated on the layer. Next, the resulting laminate is heated at 175° C. for 2 minutes to provide a battery packaging material in which base layer/adhesive layer/barrier layer/adhesive layer/thermal adhesive resin layer are laminated in this order. got

The wet tension on the substrate layer side surface of the laminate constituting the battery packaging material obtained in each example was in the range of 30 to 60 mN/m. The method for measuring the wetting tension is as follows.

<Method for measuring wet tension>
A wetting reagent conforming to JIS standards was used to measure the wetting tension of the substrate layer side of the laminate constituting the battery packaging material. The test method complied with JIS K6768:1999. Using a wet tension test mixed solution manufactured by Nacalai Tesque, the reagent soaked in a cotton swab was applied in a line of about 6 cm ² to the surface of the base material layer constituting the battery packaging material, and after 2 seconds, the liquid was applied. It was judged whether or not the membrane was broken. If the liquid film is not broken, it proceeds to the next higher surface tension mixed liquid, and if it is broken, it proceeds to the next lower surface tension mixed liquid. This operation was repeated to select a mixed liquid that could wet the surface of the test piece in 2 seconds. The wet tension was measured under an environment of 23° C. and a relative humidity of 50%.

Comparative example 1
A barrier layer made of aluminum foil (25 μm thick, JIS H4160:1994 A8021H-O) chemically treated on both sides was laminated on a polyethylene terephthalate film (12 μm thick) as a base layer by a dry lamination method. rice field. Specifically, a two-component urethane adhesive (a polyol compound and an aromatic isocyanate compound) was applied to one surface of the barrier layer to form an adhesive layer (3 μm thick) on the barrier layer. Next, the adhesive layer on the barrier layer and the substrate layer were laminated to prepare a laminate of substrate layer/adhesive layer/barrier layer. The chemical conversion treatment of the aluminum foil used as the barrier layer was performed in the same manner as in Example 1.

Next, maleic anhydride-modified polypropylene (thickness: 14 μm, placed on the barrier layer side) and random polypropylene (thickness: 10 μm, innermost layer) were co-extruded on the barrier layer of the obtained laminate to form a barrier layer. An adhesive layer/heat-fusible resin layer was laminated on the layer. Next, the obtained laminate is heated at 175° C. for 2 minutes to obtain a battery packaging material in which base layer/adhesive layer/barrier layer/adhesive layer/thermal adhesive resin layer are laminated in this order. Obtained.

Comparative example 2
In the same manner as in Comparative Example 1, a laminate of base material layer/adhesive layer/barrier layer was produced. Next, a solution (thickness after curing: 2 μm) containing maleic anhydride-modified polypropylene and a curing agent (epoxy-based) was applied onto the barrier layer of the obtained laminate, and an unstretched polypropylene film was further coated thereon. (thickness: 25 μm) to obtain a battery packaging material in which base layer/adhesive layer/barrier layer/adhesive layer/heat-fusible resin layer were laminated in this order.

Comparative example 3
In the same manner as in Example 1, a laminate of substrate layer/adhesive layer/barrier layer was produced. The chemical conversion treatment of the aluminum foil used as the barrier layer was performed in the same manner as in Example 1. Next, maleic anhydride-modified polypropylene (thickness: 20 μm, placed on the barrier layer side) and random polypropylene (thickness: 15 μm, innermost layer) were co-extruded on the barrier layer of the obtained laminate to form a barrier layer. An adhesive layer/heat-fusible resin layer was laminated on the layer. Next, the resulting laminate is heated at 190° C. for 2 minutes to provide a battery packaging material in which the substrate layer/adhesive layer/barrier layer/adhesive layer/thermal adhesive resin layer are laminated in this order. got

<Measurement of thickness of laminate>
Using a micrometer (Digimatic Micrometer manufactured by Mitutoyo Corporation), the thickness of the laminate constituting each battery packaging material obtained above was measured. Table 2 shows the results.

<Breaking energy of laminate>
For each battery packaging material obtained above, the breaking energy per unit width of 1 m in MD and TD was obtained when a tensile test was performed under the following test conditions for each battery packaging material in MD and TD. Acquire the data of the measured “measured load (N / 15 mm)-displacement curve”, save the data in csv file format, and laminate using spreadsheet software (Microsoft Excel (registered trademark)) Calculated by integrating the data until the body breaks. At this time, the breaking energy per 1 m width of each battery packaging material was converted (divided by 0.015) and calculated using the spreadsheet software. Then, the breaking energy per unit width of 1 m in MD and the breaking energy per unit width of 1 m in TD were totaled. Five battery packaging materials to be measured were prepared, and the average of three values excluding the maximum value and the minimum value among the breaking energy values for the five samples was taken as the breaking energy of the laminate. bottom. Table 2 shows the results.
(Test condition)
・Tensile tester: trade name AGS-XPlus manufactured by Shimadzu Corporation
・Test speed: 50mm/min
・ Width of test piece: 15 mm
・ Length of test piece: 100 mm
・Distance between gauge points: 30mm

For reference, FIG. 6 shows the measured load (N/15 mm)-displacement curve obtained in the tensile test (MD) of the battery packaging material of Example 5. Measured load (N / 15 mm) - The part where the data of the displacement curve is integrated is, for example, as shown in the schematic diagram of FIG. It is an integral value and corresponds to the area of the hatched portion in FIG.

<Penetration strength of laminate>
For each of the battery packaging materials obtained above, the puncture strength was measured from the substrate layer side by a method conforming to JIS Z1707:1995. Specifically, in a measurement environment of 23 ± 2 ° C. and relative humidity (50 ± 5)%, the test piece is fixed with a table with a diameter of 115 mm having an opening of 15 mm in the center and a pressing plate. A semicircular needle with a tip shape radius of 0.5 mm was pierced at a speed of 50±5 mm per minute, and the maximum stress until the needle penetrated was measured. The number of test pieces was 5, and the average value was obtained. Imada's ZTS-500N (force gauge) and MX-500N (measuring stand) were used as devices for measuring the puncture strength. Table 2 shows the results.

<Evaluation of formability>
Each battery packaging material was cut into a rectangle having a length (MD) of 90 mm and a width (TD) of 150 mm to obtain a test sample. This sample is a rectangular molding die (female mold, surface is JIS B 0659-1: 2002 Annex 1 (reference) with a diameter of 32 mm (MD) × 54 mm (TD). The maximum height roughness (Rz nominal value) specified in Table 2 is 3.2 μm) and the corresponding molding die (male mold, surface is JIS B 0659-1: 2002 Annex 1 (Reference) Using the maximum height roughness (Rz nominal value) specified in Table 2 of the comparative surface roughness standard piece, 0 at a pressing pressure (surface pressure) of 0.25 MPa The molding depth was changed by 0.5 mm from the molding depth of 0.5 mm, and 20 samples were each subjected to cold molding (pull-in one-stage molding). At this time, the test sample was placed on the female mold so that the heat-sealable resin layer side was positioned on the male mold side. Also, the clearance between the male and female dies was set to 0.5 mm. The sample after cold forming was illuminated with a penlight in a dark room, and it was confirmed whether or not pinholes and cracks had occurred in the aluminum foil due to the transmission of the light. The deepest molding depth at which pinholes and cracks do not occur in all 20 samples of aluminum foil is A mm, and the number of samples at which pinholes, etc. occur at the shallowest molding depth where pinholes, etc. occur in aluminum foil is B. A value calculated by the following formula was defined as the limit molding depth of the battery packaging material.
Limit molding depth = A mm + (0.5 mm / 20 pieces) x (20 pieces - B pieces)

The thickness of the laminate constituting the battery packaging material is 100 μm or less, and the breaking energy of the laminate is in one direction and the other direction (the one direction and the other direction) perpendicular to the thickness direction of the laminate. It can be seen that the battery packaging materials of Examples 1 to 5, which have a total tensile strength of 200 J or more, are excellent in moldability. Moreover, in these battery packaging materials, the puncture strength measured from the substrate layer 1 side was also high.

Example 6
A barrier layer made of aluminum foil (JIS H4160: 1994 A8021H-O, thickness 35 μm) with an acid-resistant film formed on both sides is formed on a biaxially oriented nylon film (thickness 25 μm) as a base layer by a dry lamination method. Laminated by Specifically, a two-component curing urethane adhesive (polyol compound and aromatic isocyanate compound) is applied to one side of an aluminum foil with an acid-resistant film formed on both sides, and an adhesive layer (after curing) is applied on the aluminum foil. thickness of 3 μm). Next, after laminating the adhesive layer on the aluminum foil and the biaxially oriented nylon film, aging treatment was performed to prepare a laminate of base layer/adhesive layer/barrier layer.

Next, a maleic anhydride-modified polypropylene (14 μm thick) as an adhesive layer and a polypropylene (10 μm thick) as a heat-fusible resin layer are co-extruded on the barrier layer of the resulting laminate. Thus, the adhesive layer/heat-fusible resin layer was laminated on the barrier layer. Next, the obtained laminate is aged and heated to form a biaxially oriented nylon film (25 μm)/adhesive layer (3 μm)/barrier layer (35 μm)/adhesive layer (14 μm)/heat-fusible resin. A battery packaging material (total thickness: 87 μm) in which layers (10 μm) were laminated in this order was obtained. Table 3 shows the laminate structure of the battery packaging material.

Lubricant layers were formed by allowing erucamide as a lubricant to exist on both sides of the resulting battery packaging material.

Example 7
A barrier layer made of aluminum foil (JIS H4160: 1994 A8021H-O, thickness 40 μm) with an acid-resistant film formed on both sides was formed on a biaxially oriented nylon film (thickness 25 μm) as a base layer by a dry lamination method. Laminated by Specifically, a two-component curing urethane adhesive (polyol compound and aromatic isocyanate compound) is applied to one side of an aluminum foil with an acid-resistant film formed on both sides, and an adhesive layer (after curing) is applied on the aluminum foil. thickness of 2 μm). Next, after laminating the adhesive layer on the aluminum foil and the biaxially oriented nylon film, aging treatment was performed to prepare a laminate of base layer/adhesive layer/barrier layer.

Next, a maleic anhydride-modified polypropylene (14 μm thick) as an adhesive layer and a polypropylene (10 μm thick) as a heat-fusible resin layer are co-extruded on the barrier layer of the resulting laminate. Thus, the adhesive layer/heat-fusible resin layer was laminated on the barrier layer. Next, the obtained laminate is aged and heated to form a biaxially oriented nylon film (25 μm)/adhesive layer (2 μm)/barrier layer (40 μm)/adhesive layer (14 μm)/heat-fusible resin. A battery packaging material (total thickness of 91 μm) in which layers (10 μm) were laminated in this order was obtained. Table 3 shows the laminate structure of the battery packaging material.

In the same manner as in Example 6, erucamide was present as a lubricant on both sides of the obtained battery packaging material to form a lubricant layer.

Example 8
A barrier layer made of aluminum foil (JIS H4160: 1994 A8021H-O, thickness 40 μm) with an acid-resistant film formed on both sides was formed on a biaxially oriented nylon film (thickness 15 μm) as a base layer by a dry lamination method. Laminated by Specifically, a two-component curing urethane adhesive (polyol compound and aromatic isocyanate compound) is applied to one side of an aluminum foil with an acid-resistant film formed on both sides, and an adhesive layer (after curing) is applied on the aluminum foil. thickness of 3 μm). Next, after laminating the adhesive layer on the aluminum foil and the biaxially oriented nylon film, aging treatment was performed to prepare a laminate of base layer/adhesive layer/barrier layer.

Next, a maleic anhydride-modified polypropylene (20 μm thick) as an adhesive layer and a polypropylene (15 μm thick) as a heat-fusible resin layer are co-extruded on the barrier layer of the resulting laminate. Thus, the adhesive layer/heat-fusible resin layer was laminated on the barrier layer. Next, the obtained laminate is aged and heated to form a biaxially oriented nylon film (15 μm)/adhesive layer (3 μm)/barrier layer (40 μm)/adhesive layer (20 μm)/heat-fusible resin. A battery packaging material (total thickness: 93 μm) in which layers (15 μm) were laminated in this order was obtained. Table 3 shows the laminate structure of the battery packaging material.

In the same manner as in Example 6, erucamide was present as a lubricant on both sides of the obtained battery packaging material to form a lubricant layer.

Example 9
A barrier layer made of aluminum foil (JIS H4160: 1994 A8021H-O, thickness 40 μm) with an acid-resistant film formed on both sides was formed on a biaxially oriented nylon film (thickness 15 μm) as a base layer by a dry lamination method. Laminated by Specifically, a two-component curing urethane adhesive (polyol compound and aromatic isocyanate compound) is applied to one side of an aluminum foil with an acid-resistant film formed on both sides, and an adhesive layer (after curing) is applied on the aluminum foil. thickness of 3 μm). Next, after laminating the adhesive layer on the aluminum foil and the biaxially oriented nylon film, aging treatment was performed to prepare a laminate of base layer/adhesive layer/barrier layer.

Next, a maleic anhydride-modified polypropylene (14 μm thick) as an adhesive layer and a polypropylene (10 μm thick) as a heat-fusible resin layer are co-extruded on the barrier layer of the resulting laminate. Thus, the adhesive layer/heat-fusible resin layer was laminated on the barrier layer. Next, the obtained laminate is aged and heated to form a biaxially oriented nylon film (15 μm)/adhesive layer (3 μm)/barrier layer (40 μm)/adhesive layer (14 μm)/heat-fusible resin. A battery packaging material (total thickness: 82 μm) in which layers (10 μm) were laminated in this order was obtained. Table 3 shows the laminate structure of the battery packaging material.

In the same manner as in Example 6, erucamide was present as a lubricant on both sides of the obtained battery packaging material to form a lubricant layer.

In Table 3, the numerical values in the laminated structure mean the thickness (μm). In addition, ONy is a biaxially oriented nylon film, DL is an adhesive layer or adhesion layer formed by a dry lamination method, ALM is an aluminum foil, PPa is an adhesion layer formed of maleic anhydride-modified polypropylene, and PP is formed of polypropylene. The heat-fusible resin layer and CPP means a heat-fusible resin layer formed of unstretched polypropylene (CPP).

<Measurement of thickness of laminate>
In the same manner as in Examples 1 to 5 and Comparative Examples 1 to 3, the thickness of the laminate constituting each battery packaging material obtained in Examples 6 to 9 was measured. Table 4 shows the results.

<Penetration strength of laminate>
In the same manner as in Examples 1 to 5 and Comparative Examples 1 to 3, each battery packaging material obtained in Examples 6 to 9 was subjected to a method according to JIS Z1707: 1995. The piercing strength was measured from Table 4 shows the results.

<Breaking energy of laminate>
For each battery packaging material obtained in Examples 6-9, the breaking energy of the laminate was measured in the same manner as in Examples 1-5 and Comparative Examples 1-3. Table 4 shows the results.

<Evaluation of curl by molding>
Each battery packaging material obtained in Examples 6 to 9 was cut into strips of TD (Transverse Direction) 150 mm×MD (Machine Direction) 90 mm, which were used as test samples. 31.6 mm x 54.5 mm rectangular male mold (surface is JIS B 0659-1: 2002 Annex 1 (reference) Maximum height roughness specified in Table 2 of comparative surface roughness standard piece (Nominal value of Rz) is 1.6 μm. Corner R 2.0 mm, ridge R 1.0 mm) and female mold with clearance of 0.3 mm (surface is JIS B 0659-1: 2002 Annex 1 (Reference) A mold with a maximum height roughness (nominal value of Rz) of 3.2 μm, corner R 2.0 mm, ridge R 1.0 mm defined in Table 2 of the surface roughness standard piece for comparison. Place the above test sample on the female mold so that the heat-sealable resin layer side is located on the male mold side, and the mold is 31.6 mm (MD) × 54.5 mm (TD) and the molding depth is 6 mm. Then, the test sample was pressed with a pressing pressure (surface pressure) of 0.25 MPa and cold-molded (pull-in one-step molding). The details of the molding positions are as shown in FIG. As shown in FIG. 8, the battery packaging material 10 was molded at a position where the shortest distance d between the rectangular molding portion M and the edge P of the battery packaging material 10 was 70.5 mm. A molding portion M indicates a position where a concave portion is formed by a mold. Next, the molded battery packaging material 10 is placed on a horizontal surface 20 as shown in FIG. height. As for the curl due to molding, the smaller the value, the smaller the curl, which is excellent as a packaging material for batteries. Table 4 shows the results.

<Evaluation of formability>
The moldability of each battery packaging material obtained in Examples 6-9 was evaluated in the same manner as in Examples 1-5 and Comparative Examples 1-3. Table 4 shows the results.

<Molding depth at which the thickness of the barrier layer becomes 20 μm>
Each of the battery packaging materials obtained in Examples 6 to 9 was cut into strips of length (MD) 90 mm×width (TD) 150 mm, which were used as test samples. Rectangular male mold with length (MD) 31.6 mm x width (TD) 54.5 mm (surface is JIS B 0659-1: 2002 Annex 1 (reference) The defined maximum height roughness (nominal value of Rz) is 1.6 μm. Corner R 2.0 mm, ridge R 1.0 mm) and a female mold with a clearance of 0.3 mm from this male mold (the surface is JIS B 0659-1: 2002 Annex 1 (reference) The maximum height roughness (Rz nominal value) specified in Table 2 of the surface roughness standard piece for comparison is 3.2 μm.Corner R 2.0 mm, Using a straight mold having a ridgeline radius of 1.0 mm, the test sample was placed on the female mold so that the heat-sealable resin layer side of the test sample was positioned on the male mold side, and the test sample was placed on the female mold. It was pressed with a pressing pressure (surface pressure) of 25 MPa and cold-formed (pull-in one-step forming).

According to this cold forming method, the forming is performed sequentially under the condition that the forming depth is increased by 0.5 mm from 2.0 mm. ) and the molding depth, and an approximate straight line was drawn to create a graph. From the graph, the forming depth at which the thickness a of the corner portion P of the barrier layer is 20 μm was obtained.

The thickness a of the barrier layer of the test sample after molding was measured by microtome (Yamato Koki Kogyo: REM-710 Litratome) is cut in the thickness direction to divide the battery packaging material into two, and the cross section of the corner P of one of the divided test samples is observed with a laser microscope (Keyence: VK- 9700). One of the divided test samples had two corner portions, and the thickness a of the barrier layer was the average value of the thickness a of the barrier layer at these corner portions. A schematic diagram of the barrier layer of the test sample after molding is shown in FIG. The position of the thickness of the corner P is the point where the radius of curvature of the corner P (curved portion) formed by molding is the smallest, and usually means the central portion from the start to the end of the curve.

1 base material layer 2 adhesive layer 3 barrier layer 4 heat-fusible resin layer 5 adhesive layer 6 surface coating layer 7 colored layer

Claims (17)

Consists of a laminate comprising at least a substrate layer, a barrier layer, and a heat-fusible resin layer in this order,
The laminate has a thickness of 100 μm or less,
Two or more lubricants are present on at least one of the surface and the interior of the heat-fusible resin layer,
The laminate has a puncture strength of 22 N or less measured from the base layer side by a method conforming to JIS Z1707:1995,
For the laminate, the breaking energy per unit width of 1 m calculated from the measured load (N / 15 mm)-displacement curve measured when a tensile test is performed under the following test conditions. The total X + Y of the breaking energy X in one direction perpendicular to the thickness direction and the breaking energy Y in the other direction perpendicular to both the one direction and the thickness direction of the laminate is 200 J or more. Packaging materials for batteries.
(Test condition)
Test speed: 50mm/min
Width of test piece: 15 mm
Gauge distance: 30mm Consists of a laminate comprising at least a substrate layer, a barrier layer, and a heat-fusible resin layer in this order,
The laminate has a thickness of 100 μm or less,
At least one of the surface and the inside of the heat-sealable resin layer is composed of saturated fatty acid amide, unsaturated fatty acid amide, substituted amide, methylolamide, saturated fatty acid bisamide, unsaturated fatty acid bisamide, fatty acid ester amide, and aromatic bisamide. there are at least two selected from the group,
The laminate has a puncture strength of 22 N or less measured from the base layer side by a method conforming to JIS Z1707:1995,
For the laminate, the breaking energy per unit width of 1 m calculated from the measured load (N / 15 mm)-displacement curve measured when a tensile test is performed under the following test conditions. The total X + Y of the breaking energy X in one direction perpendicular to the thickness direction and the breaking energy Y in the other direction perpendicular to both the one direction and the thickness direction of the laminate is 200 J or more. Packaging materials for batteries.
(Test condition)
Test speed: 50mm/min
Width of test piece: 15 mm
Gauge distance: 30mm 3. The battery packaging material according to claim 1, wherein said one direction is MD of said laminate and said other direction is TD of said laminate. The laminate according to any one of claims 1 to 3, wherein the puncture strength measured from the base material layer side by a method conforming to JIS Z1707:1995 is 15 N or more. Packaging materials for batteries. The battery packaging material according to any one of claims 1 to 4, further comprising an adhesive layer between the base layer and the barrier layer. 6. The battery packaging material according to claim 5, wherein said adhesive layer contains a coloring agent. 7. The battery packaging material according to claim 5, further comprising a colored layer between said base material layer and said adhesive layer. The battery packaging material according to any one of claims 1 to 7, further comprising a surface coating layer on the opposite side of the base layer to the barrier layer. The battery packaging material according to any one of claims 1 to 8, wherein two or more lubricants are present on at least one of the surface and the interior of the base material layer. At least one of the surface and the inside of the base material layer is selected from the group consisting of 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. 10. The battery packaging material according to any one of claims 1 to 9, wherein at least one type of the battery packaging material is present. 9. The battery packaging material according to claim 8, wherein a lubricant is present on at least one of the surface and the inside of said surface coating layer. 12. The battery packaging material according to claim 11, wherein two or more lubricants are present on at least one of the surface and the interior of the surface coating layer. At least one of the surface and the inside of the surface coating layer is coated with an amide lubricant, fatty acid amide, metal soap, hydrophilic silicone, silicone-grafted acrylic, silicone-grafted epoxy, silicone-grafted polyether, or silicone-grafted. 9. The battery packaging material according to claim 8, wherein at least one selected from the group consisting of polyetheric polyesters, block-type silicone acrylic copolymers, polyglycerol-modified silicones, paraffins, and reactive lubricants is present. A battery, wherein a battery element comprising at least a positive electrode, a negative electrode, and an electrolyte is housed in a package formed of the battery packaging material according to any one of claims 1 to 13. At least a step of laminating a substrate layer, a barrier layer, and a heat-fusible resin layer in this order to obtain a laminate,
The laminate has a thickness of 100 μm or less,
Two or more lubricants are present on at least one of the surface and the interior of the heat-fusible resin layer,
The laminate has a puncture strength of 22 N or less measured from the base layer side by a method conforming to JIS Z1707:1995,
For the laminate, the breaking energy per unit width of 1 m calculated from the measured load (N / 15 mm)-displacement curve measured when a tensile test is performed under the following test conditions. The total X + Y of the breaking energy X in one direction perpendicular to the thickness direction and the breaking energy Y in the other direction perpendicular to both the one direction and the thickness direction of the laminate is 200 J or more. A method for producing a battery packaging material.
(Test condition)
Test speed: 50mm/min
Width of test piece: 15 mm
Gauge distance: 30mm At least a step of laminating a substrate layer, a barrier layer, and a heat-fusible resin layer in this order to obtain a laminate,
The laminate has a thickness of 100 μm or less,
At least one of the surface and the inside of the heat-sealable resin layer is composed of saturated fatty acid amide, unsaturated fatty acid amide, substituted amide, methylolamide, saturated fatty acid bisamide, unsaturated fatty acid bisamide, fatty acid ester amide, and aromatic bisamide. there are at least two selected from the group,
The laminate has a puncture strength of 22 N or less measured from the base layer side by a method conforming to JIS Z1707:1995,
For the laminate, the breaking energy per unit width of 1 m calculated from the measured load (N / 15 mm)-displacement curve measured when a tensile test is performed under the following test conditions. The total X + Y of the breaking energy X in one direction perpendicular to the thickness direction and the breaking energy Y in the other direction perpendicular to both the one direction and the thickness direction of the laminate is 200 J or more. A method for producing a battery packaging material.
(Test condition)
Test speed: 50mm/min
Width of test piece: 15 mm
Gauge distance: 30mm Laminating an adhesive layer between the barrier layer and the heat-fusible resin layer,
the adhesive layer and the heat-fusible resin layer,
(1) a method of laminating the adhesive layer and the heat-fusible resin layer by co-extrusion;
(2) A method of forming a laminate in which the adhesive layer and the heat-fusible resin layer are laminated, and laminating the laminate on the barrier layer by a thermal lamination method;
(3) On the barrier layer, an adhesive for forming the adhesive layer is extruded or solution-coated, and the heat-fusible resin layer formed into a sheet in advance on the adhesive layer is thermally laminated. A method of laminating by
(4) The heat-fusible resin layer is poured through the adhesive layer while the melted adhesive layer is poured between the barrier layer and the heat-fusible resin layer that has been formed into a sheet in advance. a method of gluing the
The manufacturing method of the battery packaging material according to claim 15 or 16, wherein the method is formed by

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