Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/78—Cases; Housings; Encapsulations; Mountings
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/84—Processes for the manufacture of hybrid or EDL capacitors, or components thereof
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/102—Primary casings; Jackets or wrappings characterised by their shape or physical structure
  • H01M50/105—Pouches or flexible bags
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/116—Primary casings; Jackets or wrappings characterised by the material
  • H01M50/121—Organic material
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/116—Primary casings; Jackets or wrappings characterised by the material
  • H01M50/124—Primary casings; Jackets or wrappings characterised by the material having a layered structure
  • H01M50/126—Primary casings; Jackets or wrappings characterised by the material having a layered structure comprising three or more layers
  • H01M50/129—Primary casings; Jackets or wrappings characterised by the material having a layered structure comprising three or more layers with two or more layers of only organic material
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/131—Primary casings; Jackets or wrappings characterised by physical properties, e.g. gas permeability, size or heat resistance
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/10—Energy storage using batteries

Definitions

• the present disclosure relates to an exterior material for an electricity storage device, a method for manufacturing the same, a resin composition, and an electricity storage device.
• the exterior material is an indispensable member for sealing the power storage device elements such as electrodes and electrolytes.
• metal exterior materials have been frequently used as exterior materials for electric storage devices.
• Laminates have been proposed (see Patent Document 1, for example).
• a recess is formed by cold molding, and an electric storage device element such as an electrode or an electrolytic solution is placed in the space formed by the recess, and a heat-sealing resin is used.
• an electricity storage device in which an electricity storage device element is accommodated inside the exterior material for an electricity storage device can be obtained.
• film-like exterior materials are required to be thinner. Moreover, from the viewpoint of further increasing the energy density of the electric storage device, it is also required to form a deep concave portion in the exterior material.
• the main purpose of the first and second aspects of the present disclosure is to provide an exterior material for an electricity storage device with excellent moldability.
• power storage devices may be used for long periods of time in high-temperature and high-humidity environments.
• an electricity storage device using an electricity storage device exterior material composed of a film-like laminate as described above is placed in a high-temperature, high-humidity environment for a long period of time, the base layer and the barrier located outside the electricity storage device exterior material
• peeling easily occurs between the layers In particular, a large stress is locally applied to the exterior material for an electric storage device due to the formation of recesses by molding.
• the expansion and contraction of the base material layer make the separation between the base material layer and the barrier layer more likely to occur. be.
• a third aspect of the present disclosure provides an electricity storage device composed of a laminate including at least a substrate layer, an adhesive layer, a barrier layer, and a heat-fusible resin layer in this order.
• An exterior material for an electricity storage device which is an exterior material for an electricity storage device in which peeling between a base material layer and a barrier layer is suitably suppressed even when the exterior material for an electricity storage device after molding is placed in a high-temperature and high-humidity environment.
• the main purpose is to provide
• an exterior material for an electricity storage device composed of a laminate including, in order from the outside, at least a base material layer, a barrier layer, and a heat-fusible resin layer
• at least one layer included in the laminate contains acetic acid.
• Resin A, which is insoluble in ethyl, and resin B, which is soluble in ethyl acetate and has not reacted with resin A are blended, and furthermore, when the contents of resin A and resin B are set within a predetermined range, excellent It was found that moldability is exhibited.
• the inventors of the present disclosure have found that, in order from the outside, at least a base material layer, a barrier layer, and a heat-sealable resin layer are included in an exterior material for an electricity storage device, which is composed of a laminate. It has been found that excellent moldability is exhibited even when the mass reduction rate when at least one layer is immersed in ethyl acetate is set within a specific range.
• the exterior material for an electricity storage device is as follows. Consists of a laminate comprising, in order from the outside, at least a substrate layer, a barrier layer, and a heat-fusible resin layer, At least one layer included in the laminate constitutes a moldability improving layer,
• the moldability improving layer contains a resin A that is insoluble in ethyl acetate and a resin B that is soluble in ethyl acetate and has not reacted with the resin A,
• the exterior material for an electricity storage device, wherein the moldability improving layer has a content of the resin A of 43 mass % or more and a content of the resin B of 4 mass % or more and 57 mass % or less.
• the exterior material for an electricity storage device is as follows. Consists of a laminate comprising, in order from the outside, at least a substrate layer, a barrier layer, and a heat-fusible resin layer, An exterior material for an electricity storage device, wherein at least one layer included in the laminate constitutes a formability improving layer having a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate.
• the inventors of the present disclosure diligently studied to solve the above-described problems related to the third aspect.
• it is composed of a laminate comprising at least a substrate layer, an adhesive layer, a barrier layer, and a heat-fusible resin layer in this order, and the adhesive layer is measured using gel permeation chromatography.
• the power storage device exterior material having a molecular weight of 35000 or less, which is the peak value of the differential molecular weight distribution curve, has a base layer and a barrier layer even when the power storage device exterior material after molding is placed in a high-temperature and high-humidity environment. It was found that the delamination between the and is suitably suppressed.
• the third aspect of the present disclosure has been completed through further studies based on these findings. That is, the third aspect of the present disclosure provides inventions of the following aspects. Consists of a laminate comprising at least a substrate layer, an adhesive layer, a barrier layer, and a heat-fusible resin layer in this order,
• the adhesive layer has a peak molecular weight of 35,000 or less in a differential molecular weight distribution curve measured using gel permeation chromatography.
• an exterior material for an electricity storage device with excellent moldability. Further, according to the first aspect and the second aspect of the present disclosure, a method for manufacturing the exterior material for an electricity storage device, an electricity storage device using the exterior material for an electricity storage device, and an exterior material for the electricity storage device A resin composition can also be provided.
• an exterior material for an electricity storage device which is composed of a laminate including at least a substrate layer, an adhesive layer, a barrier layer, and a heat-fusible resin layer in this order.
• a laminate including at least a substrate layer, an adhesive layer, a barrier layer, and a heat-fusible resin layer in this order.
• FIG. 1 is a schematic diagram showing an example of a cross-sectional structure of an exterior material for an electricity storage device of the present disclosure
• FIG. 1 is a schematic diagram showing an example of a cross-sectional structure of an exterior material for an electricity storage device of the present disclosure
• BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing an example of a cross-sectional structure of an exterior material for an electricity storage device of the present disclosure
• FIG. 1 is a schematic diagram showing an example of a cross-sectional structure of an exterior material for an electricity storage device of the present disclosure
• FIG. 4 is a schematic diagram for explaining a method of housing an electricity storage device element in a package formed by the electricity storage device exterior material of the present disclosure. It is a schematic diagram of a differential molecular weight distribution curve.
• the exterior material for an electricity storage device is composed of a laminate including, in order from the outside, at least a base material layer, a barrier layer, and a heat-fusible resin layer. At least one layer included constitutes a moldability-improving layer, and the moldability-improving layer is composed of a resin A that is insoluble in ethyl acetate and a resin that is soluble in ethyl acetate and is unreacted with the resin A. and a certain resin B, wherein the moldability improving layer has a content of the resin A of 43% by mass or more and a content of the resin B of 4% by mass or more and 57% by mass or less. do.
• the exterior material for an electricity storage device is composed of a laminate including, in order from the outside, at least a base layer, a barrier layer, and a heat-fusible resin layer, and the laminate At least one layer contained in the body constitutes a moldability-improving layer having a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate.
• the power storage device exterior materials according to the first and second aspects of the present disclosure each have excellent moldability.
• the exterior material for an electricity storage device is composed of a laminate including at least a substrate layer, an adhesive layer, a barrier layer, and a heat-fusible resin layer in this order.
• the adhesive layer has a molecular weight of 35,000 or less, which is the peak value of a differential molecular weight distribution curve measured using gel permeation chromatography.
• the exterior material for an electricity storage device of the present disclosure has this configuration, so that even when the exterior material for an electricity storage device after molding is placed in a high-temperature and high-humidity environment, the gap between the base material layer and the barrier layer Peeling is suitably suppressed.
• the electrical storage device exterior material according to the first aspect of the present disclosure further includes the characteristics of the electrical storage device exterior material according to the third aspect. That is, in the power storage device exterior material according to the first aspect of the present disclosure, the power storage device exterior material includes at least a base layer, an adhesive layer, a barrier layer, and a heat-fusible resin layer. It is preferable that the adhesive layer is composed of a laminated body provided in order and has a molecular weight of 35,000 or less, which is the peak value of a differential molecular weight distribution curve measured using gel permeation chromatography.
• the power storage device exterior material according to the second aspect of the present disclosure further includes the characteristics of the power storage device exterior material according to the third aspect. That is, in the power storage device exterior material according to the second aspect of the present disclosure, the power storage device exterior material includes at least a base layer, an adhesive layer, a barrier layer, and a heat-fusible resin layer. It is preferable that the adhesive layer is composed of a laminated body provided in order and has a molecular weight of 35,000 or less, which is the peak value of a differential molecular weight distribution curve measured using gel permeation chromatography.
• the power storage device exterior material according to the third aspect of the present disclosure further includes the features of the power storage device exterior material according to the first aspect. That is, in the power storage device exterior material according to the third aspect of the present disclosure, at least one layer included in the laminate constitutes a moldability improving layer, and the moldability improving layer is dissolved in ethyl acetate. and a resin B that is dissolved in ethyl acetate and is unreacted with the resin A, and the moldability improving layer has a content of the resin A of 43% by mass or more, It is preferable that the content of the resin B is 4% by mass or more and 57% by mass or less.
• the upper limit and upper limit, the upper limit and lower limit, or the lower limit and lower limit, which are separately described, may be combined to form a numerical range.
• upper or lower limits described in a certain numerical range may be replaced with values shown in Examples.
• the barrier layer 3 which will be described later, can usually be distinguished between MD (Machine Direction) and TD (Transverse Direction) in the manufacturing process.
• MD Machine Direction
• TD Transverse Direction
• the barrier layer 3 is made of a metal foil such as an aluminum alloy foil or a stainless steel foil
• lines called rolling marks are formed on the surface of the metal foil in the rolling direction (RD) of the metal foil. shaped streaks are formed. Since the rolling marks extend along the rolling direction, the rolling direction of the metal foil can be grasped by observing the surface of the metal foil.
• the MD of the laminate usually matches the RD of the metal foil, so the surface of the metal foil of the laminate is observed to identify the rolling direction (RD) of the metal foil.
• the MD of the laminate can be identified.
• the TD of the laminate is perpendicular to the MD of the laminate, the TD of the laminate can also be specified.
• the MD of the exterior material for an electricity storage device cannot be identified due to the rolling marks of metal foil such as aluminum alloy foil or stainless steel foil, it can be identified by the following method.
• a method for confirming the MD of the exterior material for an electricity storage device there is a method for confirming the sea-island structure by observing the cross section of the heat-fusible resin layer of the exterior material for the electricity storage device with an electron microscope. In this method, the direction parallel to the cross section in which the average diameter of the island shape in the direction perpendicular to the thickness direction of the heat-fusible resin layer is maximum can be determined as the MD.
• the cross section in the length direction of the heat-fusible resin layer is changed by 10 degrees from a direction parallel to the cross section in the length direction, and the direction is perpendicular to the cross section in the length direction. (10 cross sections in total) are observed with electron micrographs to confirm the sea-island structure.
• the shape of each individual island is observed.
• the linear distance connecting the leftmost end in the direction perpendicular to the thickness direction of the heat-sealable resin layer and the rightmost end in the perpendicular direction is defined as the diameter y.
• the average of the top 20 diameters y of the island shape is calculated in descending order of diameter y.
• the direction parallel to the cross section in which the average diameter y of the island shape is the largest is determined as the MD.
• Laminated Structure and Characteristics of Electricity Storage Device Exterior Material As shown in FIG. It is composed of a laminate having heat-fusible resin layers 4 in this order.
• the base material layer 1 In the power storage device exterior material 10, the base material layer 1 is the outermost layer, and the heat-fusible resin layer 4 is the innermost layer.
• the heat-sealable resin layers 4 of the electricity storage device exterior material 10 face each other, and the peripheral edges are heat-sealed.
• the electricity storage device element is accommodated in the space formed by .
• the barrier layer 3 is the reference
• the heat-fusible resin layer 4 side is inner than the barrier layer 3
• the base layer 1 side is more than the barrier layer 3. outside.
• the exterior material 10 for an electric storage device has adhesiveness between the base material layer 1 and the barrier layer 3. It may have an adhesive layer 2 if necessary for the purpose of enhancing it.
• an adhesive layer 5 may optionally be provided between the barrier layer 3 and the heat-fusible resin layer 4 for the purpose of enhancing the adhesion between these layers.
• a surface coating layer 6 or the like may be provided on the outside of the base material layer 1 (the side opposite to the heat-fusible resin layer 4 side), if necessary.
• At least one of the layers included in the laminate constituting the electrical storage device exterior material 10 constitutes a formability improving layer.
• the moldability improving layer contains resin A and resin B.
• Resin A is a resin that does not dissolve in ethyl acetate.
• the resin B is dissolved in ethyl acetate and is unreacted with the resin A.
• the moldability improving layer has a resin A content of 43% by mass or more and a resin B content of 4% by mass or more and 57% by mass or less.
• At least one of the layers included in the laminate constituting the electrical storage device exterior material 10 has a mass reduction rate of 6% or more and 50% when immersed in ethyl acetate. It constitutes the following formability improving layer.
• the moldability-improving layer having a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate specifically refers to the mass of the moldability-improving layer measured as follows. It means that the reduction rate is 6% or more and 50% or less.
• a solvent ethyl acetate (volume 50 mL)
• the mass of the undissolved moldability improving layer is measured using the same scale (capable of measuring to four decimal places) used for measuring the mass.
• the adhesive layer 2 is a moldability improving layer
• the adhesive that forms the adhesive layer 2 may be a silicone coated PET film (release PET).
• release PET silicone coated PET film
• the adhesive layer 2 is formed by applying it to the coated surface and curing it.
• the obtained adhesive layer 2 can be peeled off from the release PET and used as a measurement target.
• the mass reduction rate of the moldability improving layer when measuring the mass reduction rate of the moldability improving layer from the exterior material for electrical storage devices, it measures by the following methods. Prepare an exterior material for a power storage device with a total area of 10 cm ⁇ 10 cm or more (total volume of the moldability improvement layer: 30 mm 3 to 40 mm 3 ), peel off the layer laminated on one side of the moldability improvement layer, and mold. Obtain a laminate in which the surface of the property-improving layer is exposed. In addition, if there is a print on the measurement target location of the exterior material for an electricity storage device, it is desirable to remove the print before measurement.). For example, if the formability improving layer is the adhesive layer 2, one of the base material layer 1 and the barrier layer 3 is peeled off from the electrical storage device exterior material.
• the laminate of either the base material layer 1 or the barrier layer 3 to which a large amount of the adhesive layer 2 is adhered is used for measuring the mass reduction rate. If a large amount of the adhesive layer 2 adheres to the barrier layer 3 side, the heat-fusible resin layer 4 is removed from the laminate before measurement (when the adhesive layer 5 is provided, the adhesive layer 5 is also removed). Weigh the mass (g) of the laminate with the surface of the formability improvement layer exposed (the one that can be measured to the fourth decimal place, if the formability improvement layer of the specified volume or more cannot be prepared, it can be measured to a smaller degree. scale).
• the laminate with the surface of the moldability improving layer exposed is immersed in a solvent (ethyl acetate (volume: 50 mL)) in a screw bottle and stored at 25° C. for 12 hours or more. After 12 hours or more, the laminate containing the undissolved moldability improving layer was removed from the solvent, washed with unused ethyl acetate, and then stored in a heating furnace at 40°C for 8 hours to sufficiently volatilize the solvent. , the mass of the laminate containing the undissolved formability-improving layer is measured using the same scale that was used to measure the mass before immersion.
• a solvent ethyl acetate (volume: 50 mL)
• the materials used are specified (for example, analysis by FT-IR, GC-MS, SEM-EDS, etc. can be used), and the main components
• the mass of the layers other than the moldability improving layer is obtained from the product of the representative specific gravity and the volume of the layers other than the moldability improving layer (thickness of cut surface ⁇ area).
• the mass reduction rate of the formability improving layer is calculated using the following formula.
• Mass reduction rate of formability improving layer [ ⁇ (mass of laminate containing formability improving layer before immersion) - (mass of laminate containing formability improving layer after immersion) ⁇ / ⁇ (before immersion The mass of the laminate including the formability improving layer) - (the mass of the laminate including the formability improving layer other than the formability improving layer) ⁇ ] ⁇ 100%
• the moldability-improving layer having such characteristics of the mass reduction rate includes, in addition to a resin (for example, a resin A described later) that constitutes the skeleton of the moldability-improving layer, the resin that forms the skeleton It has a structure containing a resin that dissolves in ethyl acetate without reacting (for example, a resin B described later), and the moldability improving layer has high flexibility, so that the moldability of the exterior material for an electric storage device is enhanced. It is considered that a resin (for example, a resin A described later) that constitutes the skeleton of the moldability-improving layer, the resin that forms the skeleton It has a structure containing a resin that dissolves in ethyl acetate without reacting (for example, a resin B described later), and the moldability improving layer has high flexibility, so that the moldability of the exterior material for an electric storage device is enhanced. It is considered that
• the moldability improving layer preferably has a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate.
• the layers constituting the moldability improving layer include the resin A that is insoluble in ethyl acetate, and the resin A that is soluble in ethyl acetate and the resin A is not particularly limited as long as the content of resin A is 43 mass % or more and the content of resin B is 4 mass % or more and 57 mass % or less.
• the layer constituting the moldability improving layer may be a layer formed of a resin having a mass reduction rate in the range of 6% or more and 50% or less. , is not particularly limited.
• the layers constituting the moldability improving layer include, for example, the surface coating layer 6, the base layer 1, the adhesive layer 2, the colored layer, the adhesive layer 5, and the heat melting layer, which will be described later.
• Adhesive resin layer 4 or the like is suitable.
• at least one of the adhesive layer 2 and the adhesive layer 5 preferably constitutes the moldability improving layer, and it is particularly preferable that the adhesive layer 2 constitutes the moldability improving layer.
• the exterior material 10 for an electricity storage device includes, for example, as shown in FIGS. It consists of a laminate comprising layers 4 in that order.
• the base material layer 1 is the outermost layer
• the heat-fusible resin layer 4 is the innermost layer.
• the heat-sealable resin layers 4 of the electricity storage device exterior material 10 face each other and the peripheral edges are heat-sealed.
• a power storage device element is accommodated in the space formed by .
• the barrier layer 3 is the reference
• the heat-fusible resin layer 4 side is inner than the barrier layer 3
• the base layer 1 side is more than the barrier layer 3. outside.
• the exterior material 10 for an electricity storage device has a barrier layer 3 and a heat-fusible resin layer 4 which are provided with an adhesive layer between these layers to enhance adhesion.
• the adhesive layer 5 may be provided as necessary.
• a surface coating layer 6 or the like may be provided on the outside of the base material layer 1 (the side opposite to the heat-fusible resin layer 4 side), if necessary.
• the thickness of the laminate constituting the power storage device exterior material 10 of the present disclosure is not particularly limited. , about 155 ⁇ m or less, about 120 ⁇ m or less.
• the thickness of the laminate constituting the power storage device exterior material 10 is preferably about 35 ⁇ m or more, about 45 ⁇ m or more, about 60 ⁇ m or more can be mentioned.
• the preferred range of the laminate constituting the power storage device exterior material 10 is, for example, about 35 to 210 ⁇ m, about 35 to 190 ⁇ m, about 35 to 180 ⁇ m, about 35 to 155 ⁇ m, about 35 to 120 ⁇ m, and about 45 to 210 ⁇ m.
• the thickness is preferably about 60 to 155 ⁇ m when making the electric storage device lighter and thinner, and about 155 to 190 ⁇ m when improving moldability.
• the thickness (total thickness) of the laminate constituting the power storage device exterior material 10 includes the base layer 1, the adhesive layer 2 provided as necessary, the barrier layer 3, The ratio of the total thickness of the adhesive layer 5, the heat-fusible resin layer 4, and the surface coating layer 6, which are optionally provided, is preferably 90% or more, more preferably 95% or more. and more preferably 98% or more.
• the electrical storage device exterior material 10 of the present disclosure includes the base material layer 1, the adhesive layer 2, the barrier layer 3, the adhesive layer 5, and the heat-fusible resin layer 4, the electrical storage device exterior
• the ratio of the total thickness of each layer to the thickness (total thickness) of the laminate constituting the material 10 is preferably 90% or more, more preferably 95% or more, and still more preferably 98% or more.
• the power storage device exterior material 10 of the present disclosure is a laminate including the base material layer 1, the adhesive layer 2, the barrier layer 3, and the heat-fusible resin layer 4, the power storage device exterior material
• the ratio of the total thickness of each layer to the thickness (total thickness) of the laminate constituting 10 is, for example, 80% or more, preferably 90% or more, more preferably 95% or more, and further preferably 98% or more. can be done.
• the exterior material for an electricity storage device is described in the examples below.
• evaluation of detachment> the ratio (number of detachments/total number) of samples in which lifting (detachment of the base material layer) occurred is preferably less than 15/20.
• the formability improving layer includes a resin A that is insoluble in ethyl acetate and a resin B that is soluble in ethyl acetate and has not reacted with the resin A.
• the moldability improving layer has a resin A content of 43% by mass or more and a resin B content of 4% by mass or more and 57% by mass or less.
• the electrical storage device exterior material of the first aspect can improve the moldability of the electrical storage device exterior material by including the moldability improving layer, compared to the case where the electrical storage device exterior material is not provided with the moldability improving layer.
• the moldability-improving layer having such characteristics has a structure including a resin A that forms the skeleton of the moldability-improving layer and a resin B that dissolves in ethyl acetate without reacting with the resin that forms the skeleton. Since the moldability-enhancing layer has high flexibility, the stress applied during molding of the exterior material for an electric storage device is alleviated and the force applied to the barrier layer is dispersed to prevent pinholes and cracks in the barrier layer. It is considered that the occurrence of is suppressed, and the moldability of the exterior material for an electric storage device is improved.
• the content of resin A in the moldability improving layer is preferably about 45% by mass or more, more preferably about 50% by mass or more, and still more preferably about 60% by mass or more. It is about 94% by mass or less, more preferably about 90% by mass or less. About 50 to 94% by mass, about 50 to 90% by mass, about 60 to 94% by mass, and about 60 to 90% by mass.
• the content of the resin B in the moldability improving layer is preferably about 6% by mass or more, more preferably about 7% by mass or more, and still more preferably about 9% by mass or more, and It is preferably about 45% by mass or less, more preferably about 40% by mass or less.
• Preferred ranges are about 4 to 45% by mass, about 4 to 40% by mass, about 6 to 57% by mass, and 6 to 45% by mass. degree, about 6 to 40% by mass, about 7 to 57% by mass, about 7 to 45% by mass, about 7 to 40% by mass, about 9 to 57% by mass, about 9 to 45% by mass, about 9 to 40% by mass are mentioned.
• the moldability improving layer is a layer having a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate. At least one of the layers included in the laminate constituting the power storage device exterior material 10 constitutes the formability improving layer.
• the power storage device exterior material of the second aspect can improve the moldability of the power storage device exterior material by including the moldability improving layer, compared to the case where the moldability improving layer is not provided. Furthermore, if the mass reduction rate of the moldability improvement layer is 6% or more, the moldability improvement effect is sufficiently exhibited, and if the mass reduction rate is 50% or less, the decrease in the cohesive force of the moldability improvement layer is suppressed. It has sufficient peel strength.
• the moldability-improving layer having such features includes, in addition to a resin constituting the skeleton of the moldability-improving layer (for example, resin A described later), ethyl acetate without reacting with the resin constituting the skeleton. and a resin (for example, a resin B described later) that dissolves in the resin, and the flexibility of the moldability improving layer is high. It is thought that by dispersing the force applied to the barrier layer, the formation of pinholes and cracks in the barrier layer is suppressed, and the moldability of the exterior material for an electric storage device is improved.
• a resin constituting the skeleton of the moldability-improving layer for example, resin A described later
• a resin for example, a resin B described later
• the layer constituting the moldability improving layer may be a layer formed of a resin having a mass reduction rate in the range of 6% or more and 50% or less. is not particularly limited.
• a surface coating layer 6, a substrate layer 1, an adhesive layer 2, a colored layer, an adhesive layer 5, a heat-fusible resin layer 4, etc., which will be described later, are suitable.
• the method for measuring the mass reduction rate of the moldability improving layer is as described above.
• the mass reduction rate when the moldability improving layer is immersed in ethyl acetate is preferably about 8% or more, more preferably about 10%. % or more, more preferably 15% or more, preferably about 45% or less, more preferably about 40% or less, still more preferably about 35% or less, and a preferable range is about 6 to 45%, About 6-40%, About 6-35%, About 8-50%, About 8-45%, About 8-40%, About 8-35%, About 10-50%, About 10-45%, 10- About 40%, about 10 to 35%, about 15 to 50%, about 15 to 45%, about 15 to 40%, and about 15 to 35%.
• the moldability improving layer preferably has a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate, and the mass reduction rate is It is preferably about 8% or more, more preferably about 10% or more, still more preferably 15% or more, and is preferably about 45% or less, more preferably about 40% or less, further preferably about 35% or less.
• the preferred range is about 6 to 45%, about 6 to 40%, about 6 to 35%, about 8 to 50%, about 8 to 45%, about 8 to 40%, about 8 to 35%, 10 to About 50%, about 10 to 45%, about 10 to 40%, about 10 to 35%, about 15 to 50%, about 15 to 45%, about 15 to 40%, and about 15 to 35%.
• the moldability improving layer preferably contains two or more types of resins.
• the moldability improving layer of the second aspect preferably contains a resin A insoluble in ethyl acetate, and the moldability improving layer preferably has a resin A content of 40% by mass or more.
• the moldability improving layer contains a resin A and a resin B that is dissolved in ethyl acetate and has not reacted with the resin A, and the content of the resin B is 5% by mass or more. It is preferably 60% by mass or less.
• the moldability improving layer of the second aspect contains resin A and resin B, the content of resin A is 40% by mass or more, and the content of resin B is 5% by mass or more and 60% by mass or less.
• the moldability improving layer of the second aspect contains resin A and resin B, the content of resin A is 40% by mass or more, and the content of resin B is 5% by mass or more and 60% by mass or less.
• the content of resin A in the moldability improving layer is preferably about 40% by mass or more, more preferably 43% by mass or more, still more preferably 45% by mass or more, and still more preferably about 50% by mass or more.
• the content of the resin B in the moldability improving layer is preferably about 5% by mass or more, preferably about 6% by mass or more, more preferably about 7% by mass or more, and still more preferably about 9% by mass.
• % by mass or more preferably about 60% by mass or less, more preferably about 45% by mass or less, and even more preferably about 40% by mass or less, preferably about 5 to 60% by mass, 5 to About 45% by mass, about 5-40% by mass, about 6-60% by mass, about 6-45% by mass, about 6-40% by mass, about 7-60% by mass, about 7-45% by mass, 7-40% by mass about 9 to 60% by mass, about 9 to 45% by mass, and about 9 to 40% by mass.
• the fact that the resin A is insoluble in ethyl acetate specifically means the following.
• ethyl acetate is removed by the method shown in ⁇ Measurement of mass reduction rate of moldability improving layer> above, If Resin A remains as a solid and is not detected in ethyl acetate after immersion, Resin A is not dissolved in ethyl acetate.
• the laminate when evaluating a laminate in which the surface of the formability improving layer is exposed, the laminate is immersed in ethyl acetate by the method shown in ⁇ Measurement of mass reduction rate of formability improving layer> above, and then ethyl acetate is added.
• ethyl acetate is added.
• resin A is a urethane resin
• the urethane resin does not dissolve in ethyl acetate unless urethane bonds, which are the main skeleton of the urethane resin, are detected from ethyl acetate after immersing resin A in ethyl acetate. be able to.
• resin B is dissolved in ethyl acetate and is unreacted with resin A specifically means the following.
• the formability improving layer alone or the laminate in which the surface of the formability improving layer is exposed is immersed in ethyl acetate, and then the formability improving layer Resin B is considered to be unreacted with Resin A when a mass reduction of 6% or more occurs in the reaction and when a component of Resin B is detected in ethyl acetate.
• Resin A is not particularly limited as long as it is a resin that does not dissolve in ethyl acetate, and specific examples include urethane-based resins, polyamide-based resins (nylon 6, nylon 66, nylon 12, copolyamide, etc.), and polyolefin-based resins. (polyolefin, cyclic polyolefin, acid-modified polyolefin, acid-modified cyclic polyolefin, etc.), polycarbonate-based resin, polyester-based resin, polyether-based resin, and the like. Among these, urethane-based resins are particularly preferable because they are excellent in adhesiveness, flexibility, and stretchability.
• the resin A contained in the moldability improving layer the resin A contained in the moldability improving layer may be of only one type, or may be of two or more types.
• Urethane-based resins include, for example, urethane-based resins containing a first agent containing a polyol compound and a second agent containing an isocyanate compound.
• Preferred examples include a two-pack curable urethane resin in which a polyol such as a polyester polyol, a polyether polyol, or an acrylic polyol is used as the first agent and an aromatic or aliphatic polyisocyanate is used as the second agent.
• examples of the urethane-based resin include a polyurethane adhesive containing an isocyanate compound and a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance.
• examples of the urethane-based resin include a urethane-based resin containing a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance and a polyol compound.
• a urethane-based resin for example, a urethane-based resin obtained by reacting a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance with moisture in the air and curing the resin can be used.
• the polyol compound it is preferable to use a polyester polyol having a hydroxyl group in a side chain in addition to the terminal hydroxyl group of the repeating unit.
• Examples of the second agent include aliphatic, alicyclic, aromatic, and araliphatic isocyanate compounds.
• isocyanate compounds include hexamethylene diisocyanate (HDI), xylylene diisocyanate (XDI), isophorone diisocyanate (IPDI), hydrogenated XDI (H6XDI), hydrogenated MDI (H12MDI), tolylene diisocyanate (TDI), and diphenylmethane diisocyanate. (MDI), naphthalene diisocyanate (NDI), and the like.
• polyfunctional isocyanate-modified products of one or more of these diisocyanates are also included.
• a polymer for example, a trimer
• a polyisocyanate compound for example, a polyisocyanate compound.
• Such multimers include adducts, biurets, nurates and the like. Adhesion, flexibility, and stretchability are enhanced by forming the moldability improving layer from a urethane-based resin.
• the resin B is not particularly limited as long as it is dissolved in ethyl acetate and included in the moldability improving layer in an unreacted state with the resin A.
• Specific examples include acrylic resins, epoxy resins, vinyl resins, polycarbonate resins, polystyrene resins, and silicone resins.
• the resin (for example, epoxy resin) exemplified as resin B is known to react with the resin (urethane resin) exemplified as resin A, but in the present disclosure, resin B reacts with resin A. Therefore, even if the resin B is an epoxy resin, for example, an epoxy resin that does not react with the urethane resin of the resin A is used.
• the resin B does not react with the resin A (does not react) means that the reactive functional group that reacts with the resin A, the first agent (main agent) and the second agent (curing agent) that constitute the resin A is added to the resin. B substantially does not have (not at all or only a little), or poor reactivity, or the first agent (main agent) and the second agent that constitute the resin A Even if the resin B has a reactive functional group that reacts with the agent (curing agent), the reaction rate is low, and the first agent (main agent) and the second agent (curing agent) react first and cure. It means that the resin A and the resin B of are generally not crosslinked.
• the resin A and the resin B may be the same resin system as long as they satisfy the respective definitions described above.
• the base material layer 1 is a layer provided for the purpose of exhibiting a function as a base material of an exterior material for an electric storage device.
• the base material layer 1 is located on the outer layer side of the exterior material for electrical storage devices.
• the substrate layer 1 may be the moldability improving layer.
• the details of the formability improving layers of the first aspect and the second aspect are respectively as described above.
• stress can be dispersed in the substrate layer 1, so cracks can be suppressed without applying local force to the barrier layer 3 during molding, and moldability is improved. .
• the material forming the base material layer 1 of the present disclosure is not particularly limited as long as it functions as a base material, that is, at least has insulating properties.
• the base material layer 1 can be formed using, for example, a resin, and the resin may contain additives described later.
• the base material layer 1 when used as the moldability improving layer, it is preferable to form the base material layer 1 from the above-described resin preferable for the moldability improving layer.
• the substrate layer 1 when the substrate layer 1 is made of resin, the substrate layer 1 can be made of, for example, a resin film.
• the base material layer 1 when the base material layer 1 is laminated with the barrier layer 3 and the like to manufacture the power storage device exterior material 10 of the present disclosure, the previously formed resin film is used as the base material layer. 1 may be used.
• the resin forming the base material layer 1 may be formed into a film on the surface of the barrier layer 3 or the like by extrusion molding or coating to form the base material layer 1 formed of a resin film.
• the resin film may be an unstretched film or a stretched film. Examples of stretched films include uniaxially stretched films and biaxially stretched films, with biaxially stretched films being preferred.
• the stretching method for forming the biaxially stretched film includes, for example, a sequential biaxial stretching method, an inflation method, a simultaneous biaxial stretching method, and the like.
• Methods for applying the resin include a roll coating method, a gravure coating method, an extrusion coating method, and the like.
• resins forming the base material layer 1 include resins such as polyester, polyamide, polyolefin, epoxy resin, acrylic resin, fluororesin, polyurethane, silicon resin, phenolic resin, and modified products of these resins. are mentioned. Further, the resin forming the base material layer 1 may be a copolymer of these resins or a modified product of the copolymer. Furthermore, it may be a mixture of these resins.
• the base material layer 1 preferably contains these resins as a main component, and more preferably contains polyester or polyamide as a main component.
• the main component means that the resin component contained in the base layer 1 has a content of, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, and further preferably 80% by mass. % or more, more preferably 90 mass % or more, more preferably 95 mass % or more, still more preferably 98 mass % or more, still more preferably 99 mass % or more.
• the base material layer 1 contains polyester or polyamide as a main component means that the content of polyester or polyamide among the resin components contained in the base material layer 1 is, for example, 50% by mass or more, preferably 60% by mass. % or more, more preferably 70 mass % or more, still more preferably 80 mass % or more, still more preferably 90 mass % or more, still more preferably 95 mass % or more, still more preferably 98 mass % or more, still more preferably 99 mass % or more means that
• polyesters and polyamides are preferred as resins forming the base material layer 1 .
• the substrate layer 1 when the substrate layer 1 is used as the moldability improving layer in the first aspect and the second aspect, the substrate layer 1 may be composed of a resin preferable as the moldability improving layer. preferable.
• polyester examples include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, and copolymerized polyester.
• copolyester examples include copolyester having ethylene terephthalate as a main repeating unit.
• copolymer polyester polymerized with ethylene isophthalate with ethylene terephthalate as the main repeating unit hereinafter abbreviated after polyethylene (terephthalate / isophthalate)
• polyethylene (terephthalate / adipate) polyethylene (terephthalate / sodium sulfoisophthalate)
• polyethylene (terephthalate/sodium isophthalate) polyethylene (terephthalate/phenyl-dicarboxylate), polyethylene (terephthalate/decanedicarboxylate), and the like.
• These polyesters may be used singly or in combination of two or more.
• polyamide specifically, aliphatic polyamide such as nylon 6, nylon 66, nylon 610, nylon 12, nylon 46, copolymer 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, polyamide MXD6 (polymetallic Polyamides containing aromatics such as silylene adipamide); alicyclic polyamides such as polyamide PACM6 (polybis(4-aminocyclohexyl)methane adipamide); Copolymerized polyamides, polyesteramide copolymers and polyetheresteramide copolymers which are copolymers of copolymerized polyamides with polyesters or polyalkylene ether glycols; and polyamides such
• the substrate layer 1 preferably includes at least one of a polyester film, a polyamide film, and a polyolefin film, preferably includes at least one of a stretched polyester film, a stretched polyamide film, and a stretched polyolefin film, It is more preferable to include at least one of an oriented polyethylene terephthalate film, an oriented polybutylene terephthalate film, an oriented nylon film, and an oriented polypropylene film, and a biaxially oriented polyethylene terephthalate film, a biaxially oriented polybutylene terephthalate film, and a biaxially oriented nylon film. , biaxially oriented polypropylene film.
• the base material layer 1 may be a single layer, or may be composed of two or more layers.
• the substrate layer 1 may be a laminate obtained by laminating resin films with an adhesive or the like, or may be formed by co-extrusion of resin to form two or more layers. It may be a laminate of resin films.
• a laminate of two or more resin films formed by coextrusion of resin may be used as the base material layer 1 without being stretched, or may be used as the base material layer 1 by being uniaxially or biaxially stretched.
• the laminate of two or more resin films in the substrate layer 1 include a laminate of a polyester film and a nylon film, a laminate of nylon films of two or more layers, and a laminate of polyester films of two or more layers. etc., preferably a laminate of a stretched nylon film and a stretched polyester film, a laminate of two or more layers of stretched nylon films, and a laminate of two or more layers of stretched polyester films.
• the substrate layer 1 is a laminate of two layers of resin films, a laminate of polyester resin films and polyester resin films, a laminate of polyamide resin films and polyamide resin films, or a laminate of polyester resin films and polyamide resin films.
• a laminate is preferred, and a laminate of polyethylene terephthalate film and polyethylene terephthalate film, a laminate of nylon film and nylon film, or a laminate of polyethylene terephthalate film and nylon film is more preferred.
• the polyester resin is resistant to discoloration when, for example, an electrolytic solution adheres to its surface. It is preferably located in the outermost layer.
• the two or more layers of resin films may be laminated via an adhesive.
• the adhesive layer formed by the adhesive is also preferably a formability improving layer.
• Preferred adhesives are the same as those exemplified for the adhesive layer 2 described later.
• the method for laminating two or more layers of resin films is not particularly limited, and known methods can be employed. Examples thereof include dry lamination, sandwich lamination, extrusion lamination, thermal lamination, and the like. A lamination method is mentioned. When laminating by a dry lamination method, it is preferable to use a polyurethane adhesive as the adhesive. At this time, the thickness of the adhesive is, for example, about 2 to 5 ⁇ m.
• an anchor-coat layer on a resin film.
• the anchor coat layer include the same adhesives as those exemplified for the adhesive layer 2 described later.
• the thickness of the anchor coat layer is, for example, about 0.01 to 1.0 ⁇ m.
• At least one of the surface and the inside of the substrate layer 1 may contain additives such as lubricants, flame retardants, antiblocking agents, antioxidants, light stabilizers, tackifiers, and antistatic agents. good. Only one type of additive may be used, or two or more types may be mixed and used.
• the surface and the inside of the base material layer 1 contains a lubricant.
• the lubricant is not particularly limited, but preferably includes an amide-based lubricant.
• Specific examples of amide lubricants include saturated fatty acid amides, unsaturated fatty acid amides, substituted amides, methylolamides, saturated fatty acid bisamides, unsaturated fatty acid bisamides, fatty acid ester amides, and aromatic bisamides.
• saturated fatty acid amides include lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, and hydroxystearic acid amide.
• unsaturated fatty acid amides include oleic acid amide and erucic acid amide.
• 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.
• methylolamide include methylol stearamide.
• 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.
• 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.
• fatty acid ester amides include stearamide ethyl stearate.
• aromatic bisamide include m-xylylenebisstearic acid amide, m-xylylenebishydroxystearic acid amide, N,N'-distearyl isophthalic acid amide and the like.
• the lubricants may be used singly or in combination of two or more, preferably in combination of two or more.
• the amount of the lubricant is not particularly limited, but is, for example, about 3 mg/m 2 or more, preferably about 4 mg/m 2 or more, and about 5 mg/m 2 or more.
• the amount of lubricant present on the surface of the substrate layer 1 is, for example, about 15 mg/m 2 or less, preferably about 14 mg/m 2 or less, and about 10 mg/m 2 or less.
• the preferred range of the amount of lubricant present on the surface of the base material layer 1 is about 3 to 15 mg/m 2 , about 3 to 14 mg/m 2 , about 3 to 10 mg/m 2 , and about 4 to 15 mg/m 2 . , about 4 to 14 mg/m 2 , about 4 to 10 mg/m 2 , about 5 to 15 mg/m 2 , about 5 to 14 mg/m 2 , and about 5 to 10 mg/m 2 .
• the lubricant present on the surface of the substrate layer 1 may be obtained by exuding the lubricant contained in the resin constituting the substrate layer 1, or by coating the surface of the substrate layer 1 with the lubricant.
• the thickness of the base material layer 1 is not particularly limited as long as it functions as a base material.
• the thickness of the base layer 1 is, for example, about 50 ⁇ m or less, preferably about 35 ⁇ m or less, 11 ⁇ m or less, and 8 ⁇ m or less.
• the preferable range of the thickness of the base material layer 1 is about 3 to 50 ⁇ m, about 3 to 35 ⁇ m, about 3 to 11 ⁇ m, about 3 to 8 ⁇ m, about 10 to 50 ⁇ m, and about 10 to 35 ⁇ m. is preferably about 3 to 35 ⁇ m, about 3 to 11 ⁇ m, or about 3 to 8 ⁇ m, and about 35 to 50 ⁇ m is preferable for improving moldability.
• the thickness of the resin film constituting each layer is not particularly limited, but is, for example, about 2 ⁇ m or more, preferably about 10 ⁇ m or more, about 18 ⁇ m or greater.
• the thickness of the resin film forming each layer is, for example, about 33 ⁇ m or less, preferably about 28 ⁇ m or less, about 23 ⁇ m or less, about 18 ⁇ m or less, 11 ⁇ m or less, and 8 ⁇ m or less.
• the preferable range of thickness of the resin film constituting each layer is about 2 to 33 ⁇ m, about 2 to 28 ⁇ m, about 2 to 23 ⁇ m, about 2 to 18 ⁇ m, about 10 to 33 ⁇ m, about 10 to 28 ⁇ m, 10 to About 23 ⁇ m, about 10 to 18 ⁇ m, about 18 to 33 ⁇ m, about 18 to 28 ⁇ m, about 18 to 23 ⁇ m, about 2 to 11 ⁇ m, and about 2 to 8 ⁇ m.
• the adhesive layer 2 is intended to enhance the adhesion between the base material layer 1 and the barrier layer 3 (or the corrosion-resistant film).
• the purpose is a layer provided between these, if desired.
• the adhesive layer 2 is used as a formability improving layer.
• the details of the formability improving layer are as described above.
• the adhesive layer 2 is used as a moldability improving layer, it is provided between the base material layer 1 and the barrier layer 3 (or the corrosion-resistant coating), so that the elongation of the base material layer 1 caused by molding and the barrier layer Since it is possible to follow both the elongation of 3 and relax the stress, the moldability is improved.
• the adhesive layer 2 is formed with 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 is not limited, but may be any of a chemical reaction type, a solvent volatilization type, a hot melt type, a hot pressure type, and the like. Further, it may be a two-liquid curing adhesive (two-liquid adhesive), a one-liquid curing adhesive (one-liquid adhesive), or a resin that does not involve a curing reaction. Further, the adhesive layer 2 may be a single layer or multiple layers. In the first aspect and the second aspect, when the adhesive layer 2 is used as a moldability improving layer, it is preferable to form the adhesive layer 2 with a resin preferable for the moldability improving layer.
• the adhesive component contained in the adhesive include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, polyester such as copolymer polyester; polyether; polyurethane; epoxy resin; Phenolic resins; polyamides such as nylon 6, nylon 66, nylon 12, and copolymerized polyamides; polyolefin resins such as polyolefins, cyclic polyolefins, acid-modified polyolefins, and acid-modified cyclic polyolefins; polyvinyl acetate; cellulose; (meth)acrylic resins; polyimide; polycarbonate; amino resin such as urea resin and melamine resin; rubber such as chloroprene rubber, nitrile rubber and styrene-butadiene rubber; These adhesive components may be used singly or in combination of two or more.
• polyurethane adhesives are preferred.
• the adhesive strength of these adhesive resins can be increased by using an appropriate curing agent in combination.
• the curing agent is selected from among polyisocyanates, polyfunctional epoxy resins, oxazoline group-containing polymers, polyamine resins, acid anhydrides, etc., depending on the functional groups of the adhesive component.
• polyurethane adhesives examples include polyurethane adhesives containing a first agent containing a polyol compound and a second agent containing an isocyanate compound.
• a two-component curing type polyurethane adhesive is used in which a polyol such as polyester polyol, polyether polyol, or acrylic polyol is used as the first agent and an aromatic or aliphatic polyisocyanate is used as the second agent.
• polyurethane adhesives include polyurethane adhesives containing an isocyanate compound and a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance.
• polyurethane adhesives examples include polyurethane adhesives containing a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance and a polyol compound.
• polyurethane adhesives examples include polyurethane adhesives obtained by reacting a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance with moisture in the air and curing the compound.
• the polyol compound it is preferable to use a polyester polyol having a hydroxyl group in a side chain in addition to the terminal hydroxyl group of the repeating unit.
• the second agent examples include aliphatic, alicyclic, aromatic, and araliphatic isocyanate compounds.
• isocyanate compounds include hexamethylene diisocyanate (HDI), xylylene diisocyanate (XDI), isophorone diisocyanate (IPDI), hydrogenated XDI (H6XDI), hydrogenated MDI (H12MDI), tolylene diisocyanate (TDI), and diphenylmethane diisocyanate. (MDI), naphthalene diisocyanate (NDI), and the like.
• polyfunctional isocyanate-modified products of one or more of these diisocyanates are also included.
• a polymer for example, a trimer
• Such multimers include adducts, biurets, nurates and the like. Since the adhesive layer 2 is formed of a polyurethane adhesive, the exterior material for an electric storage device is imparted with excellent electrolyte resistance, and even if the electrolyte adheres to the side surface, the base layer 1 is suppressed from being peeled off. .
• the adhesive layer 2 is a layer provided between the base layer 1 and the barrier layer 3 for the purpose of increasing the adhesion between the base layer 1 and the barrier layer 3. is. 3rd aspect WHEREIN: It is preferable that the adhesive bond layer 2 contains two or more types of resin.
• the adhesive layer 2 disposed between the base material layer 1 and the barrier layer 3 contains two or more types of resins, so that molecules of different resins are Concentration of force on the adhesive interface between the base material layer 1 or the barrier layer 3 and the adhesive layer 2 due to dislocation of molecular entanglement during deformation such as entanglement, molding, and contraction of the base material layer due to wet heat is suppressed.
• delamination between the base material layer and the barrier layer is preferably suppressed.
• the adhesive layer 2 is characterized by having a peak molecular weight of 35000 or less in a differential molecular weight distribution curve measured using gel permeation chromatography.
• the adhesive layer 2 disposed between the base layer 1 and the barrier layer 3 has such a specific molecular weight, so flexibility is maintained. Delamination between the base material layer and the barrier layer is preferably suppressed even when the exterior material for an electricity storage device after being applied and molded is placed in a high-temperature and high-humidity environment.
• the adhesive layer 2 preferably contains two or more resins.
• peeling between the base material layer and the barrier layer is suitably suppressed even when placed in a high-temperature and high-humidity environment.
• It contains two or more types of resins, and the resin with a specific molecular weight provides flexibility, the other resins hold the adherend, and each resin entangles and relaxes, making it resistant to high-temperature and high-humidity environments. Delamination between the base material layer and the barrier layer is more preferably suppressed even when placed.
• the method for measuring the molecular weight which is the peak value of the differential molecular weight distribution curve, is as follows.
• An adhesive layer is obtained from the exterior material for an electricity storage device and used as a measurement sample.
• gel permeation chromatography e.g., Shimadzu LC-6AD (pump) and RID-10A (differential refractometer) was used, and each molecular weight (logarithmic value) was measured under the following measurement conditions. , the concentration fraction of each molecular weight is sequentially integrated to obtain an integrated molecular weight distribution curve.
• a differential molecular weight distribution curve is obtained by obtaining the differential value of the curve at each molecular weight, and the molecular weight corresponding to the peak value on the vertical axis (dw/d(Log(M))) is obtained.
• the differential molecular weight distribution curve is a graph in which the horizontal axis indicates the molecular weight and the vertical axis indicates the value obtained by differentiating the concentration fraction by the logarithmic value of the molecular weight.
• the molecular weight at the position where the value obtained by differentiating the concentration fraction by the logarithmic value of the molecular weight is the highest is the molecular weight at which the peak value of the differential molecular weight distribution curve (see the position of P in FIG. 6).
• K-LG manufactured by Shodex
• the column temperature is normal temperature (25° C.).
• the molecular weight at which the peak value of the differential molecular weight distribution curve of the adhesive layer 2 is preferably about 30,000 or less, more preferably about 20,000 or less, and further It is preferably about 10000 or less, more preferably about 100 or more, more preferably about 200 or more, still more preferably about 300 or more, still more preferably 1000 or more, still more preferably 5000 or more, still more preferably 6500 or more, still more preferably 6500 or more is 8000 or more, and the preferred range is about 100 to 30000, about 200 to 30000, about 300 to 30000, about 1000 to 30000, about 5000 to 30000, about 6500 to 30000, about 8000 to 30000, about 100 to 20000 , about 200 to 20000, about 300 to 20000, about 1000 to 20000, about 5000 to 20000, about 6500 to 20000, about 8000 to 20000, about 100 to 10000, about 200 to 10000, about 300 to 10000, about 1000
• the adhesive layer 2 is formed from 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 is not particularly limited as long as the molecular weight, which is the peak value of the differential molecular weight distribution curve of the adhesive layer 2, is 35000 or less. Any of a mold, a heat melting type, a hot pressing type, and the like may be used. Further, it may be a two-liquid curing adhesive (two-liquid adhesive), a one-liquid curing adhesive (one-liquid adhesive), or a resin that does not involve a curing reaction. Further, the adhesive layer 2 may be a single layer or multiple layers.
• the adhesive layer 2 preferably has a mass reduction rate of about 6% or more, more preferably about 8% or more, even more preferably about 10% or more, even more preferably when immersed in ethyl acetate. is about 15% or more, preferably about 50% or less, more preferably about 45% or less, even more preferably about 40% or less, further preferably about 35% or less, and a preferred range is 6 to About 50%, about 6-45%, about 6-40%, about 6-35%, about 8-50%, about 8-45%, about 8-40%, about 8-35%, 10-50% about 10 to 45%, about 10 to 40%, about 10 to 35%, about 15 to 50%, about 15 to 45%, about 15 to 40%, and about 15 to 35%.
• the flexibility of the adhesive layer is high, so even when placed in a high-temperature and high-humidity environment, detachment is preferably suppressed.
• a specific method for measuring the mass reduction rate is as follows.
• the adhesive layer 2 alone can be produced, the adhesive is applied to a Si-coated PET film (release PET), cured, and then peeled off from the release PET. Measure the mass (g) on a balance capable of measuring up to (mass of the adhesive layer before immersion).
• the adhesive layer is immersed in a solvent (ethyl acetate (volume: 50 mL)) in a screw bottle and stored at 25°C for 12 hours or longer. If after 12 hours of storage it is still not fully dissolved, store for a few more hours.
• a solvent ethyl acetate (volume: 50 mL)
• the mass of the undissolved adhesive layer is measured using the same scale (capable of measuring up to four decimal places) used for measuring .
• the mass reduction rate of the adhesive layer 2 from the exterior material for electrical storage devices which concerns on a 3rd aspect it measures by the following methods. Using an exterior material for a power storage device having a total area of 10 cm ⁇ 10 cm or more (total volume of adhesive layer 2: 30 mm 3 to 40 mm 3 ), substrate layer 1 or barrier layer 3 is peeled off, and adhesive layer 2 is removed. expose the If it is not possible to prepare an electrical storage device exterior material having a total area of 10 cm ⁇ 10 cm or more, an electrical storage device exterior material having the largest possible area is prepared. In addition, if there is a print on the measurement target location of the power storage device exterior material, it is desirable to remove the print before performing the measurement.
• the mass reduction rate is measured using either the base material layer 1 or the barrier layer 3 to which a large amount of the adhesive layer 2 adheres. Measurement is performed after peeling off the adhesive resin layer (when the adhesive layer 5 is provided, the adhesive layer 5 is also peeled off). A balance that can measure either the base material layer 1 or the barrier layer 3 to which a large amount of the adhesive layer 2 is attached to the fourth decimal place (if the adhesive layer 2 of the specified volume or more cannot be prepared, the scale can be measured to a smaller value). Measure the mass (g) with a weighing scale). The laminate with the surface of the adhesive layer 2 exposed is immersed in a solvent (ethyl acetate (volume: 50 mL)) in a screw bottle and stored at 25° C. for 12 hours or more.
• a solvent ethyl acetate (volume: 50 mL)
• the undissolved adhesive layer was removed from the solvent, washed with unused ethyl acetate, stored in a heating furnace at 40°C for 8 hours, and the solvent was sufficiently volatilized. Measure the mass again with the same scale that was used to measure .
• the materials used for layers other than the adhesive layer 2 of the laminate whose mass is to be measured, specify the materials used (for example, analysis by FT-IR, GC-MS, SEM-EDS, etc. can be used), and represent the main components
• the mass of the layers other than the adhesive layer 2 is obtained from the product of the specific gravity and the volume of the layers other than the adhesive layer 2 (thickness of cut surface ⁇ area).
• the mass reduction rate of the adhesive layer 2 is calculated using the following formula.
• Mass reduction rate of adhesive layer 2 [ ⁇ (mass of laminate containing adhesive layer 2 before immersion) - (mass of laminate containing adhesive layer 2 after immersion) ⁇ / ⁇ (before immersion The mass of the laminate containing the adhesive layer 2) - (the mass of the laminate containing the adhesive layer 2 other than the adhesive layer 2) ⁇ ] ⁇ 100%
• the adhesive layer 2 preferably contains two or more kinds of resins. Further, the adhesive layer 2 preferably contains a resin A that is insoluble in ethyl acetate, and the content of the resin A in the adhesive layer 2 is preferably 40% by mass or more. When the adhesive layer 2 contains such a resin A, by holding the adherend, even when placed in a high-temperature and high-humidity environment, the separation between the base material layer and the barrier layer is more favorable. Suppressed.
• the adhesive layer 2 contains a resin A and a resin B that dissolves in ethyl acetate and is unreacted with the resin A, and the content of the resin B is 5% by mass or more and 60% by mass or less. is preferred.
• the adhesive layer 2 contains such a resin A and a resin B, in addition to the resin A constituting the skeleton of the adhesive layer, a resin B that dissolves in ethyl acetate without reacting with the resin constituting the skeleton. and has high flexibility while holding the adherend, so even when placed in a high-temperature and high-humidity environment, the separation between the base layer and the barrier layer is more suitable. considered to be suppressed.
• the adhesive layer 2 contains resin A and resin B, the content of resin A being 40 mass % or more, and the content of resin B being 5 mass % or more and 60 mass % or less.
• the content of resin A in the adhesive layer 2 is preferably about 40% by mass or more, more preferably about 43% by mass or more, still more preferably about 45% by mass or more, and still more preferably about 50% by mass. % or more, more preferably about 60% by mass or more, preferably about 94% by mass or less, more preferably about 90% by mass or less. about 43 to 94% by mass, about 43 to 90% by mass, about 45 to 94% by mass, about 45 to 90% by mass, about 50 to 94% by mass, about 50 to 90% by mass, 60 to 94% by mass %, and about 60 to 90% by mass.
• the content of the resin B in the adhesive layer 2 is preferably about 5% by mass or more, preferably about 6% by mass or more, more preferably about 7% by mass or more, further preferably about 9% by mass or more. % by mass or more, preferably about 60% by mass or less, more preferably about 45% by mass or less, and even more preferably about 40% by mass or less. About 45% by mass, about 5 to 40% by mass, about 6 to 60% by mass, about 6 to 45% by mass, about 6 to 40% by mass, about 7 to 60% by mass, about 7 to 45% by mass, 7 to About 40% by mass, about 9 to 60% by mass, about 9 to 45% by mass, and about 9 to 40% by mass.
• the fact that the resin A does not dissolve in ethyl acetate specifically means the following.
• the adhesive layer 2 alone after immersing it in ethyl acetate by the method shown in ⁇ Measurement of Mass Reduction Rate of Adhesive Layer> above, when the ethyl acetate is removed, Resin A remains as a solid, If the resin A is not detected in ethyl acetate after immersion, it is assumed that the resin A does not dissolve in ethyl acetate.
• the layer is immersed in ethyl acetate by the method shown in ⁇ Measurement of mass reduction rate of the adhesive layer> above, and then the ethyl acetate is removed.
• the resin A component is detected from the surface of the base material layer 1 or the barrier layer 3 to which the adhesive layer 2 is attached, and the component of the resin A is not detected from the ethyl acetate after the immersion, the resin A shall not be dissolved.
• resin A is a urethane resin
• the urethane resin does not dissolve in ethyl acetate unless urethane bonds, which are the main skeleton of the urethane resin, are detected from ethyl acetate after immersing resin A in ethyl acetate. be able to.
• the resin B is dissolved in ethyl acetate and is unreacted with the resin A has the following meaning. After immersion in ethyl acetate by the method shown in ⁇ Measurement of mass reduction rate of adhesive layer>, when mass decrease of 6% or more occurs and when resin B component is detected in ethyl acetate Resin B is assumed to be unreacted with resin A.
• Resin A is not particularly limited as long as it is a resin that does not dissolve in ethyl acetate, and specific examples include urethane-based resins, polyamide-based resins (nylon 6, nylon 66, nylon 12, copolyamide, etc.), and polyolefin-based resins. (polyolefin, cyclic polyolefin, acid-modified polyolefin, acid-modified cyclic polyolefin, etc.), polycarbonate-based resin, polyester-based resin, polyether-based resin, and the like. Among these, urethane-based resins are particularly preferable because they are excellent in adhesiveness, flexibility, and stretchability. When the resin A is contained in the adhesive layer 2, the resin A contained in the adhesive layer 2 may be of only one type, or may be of two or more types.
• Urethane-based resins include, for example, urethane-based resins containing a first agent containing a polyol compound and a second agent containing an isocyanate compound.
• Preferred examples include a two-pack curable urethane resin in which a polyol such as a polyester polyol, a polyether polyol, or an acrylic polyol is used as the first agent and an aromatic or aliphatic polyisocyanate is used as the second agent.
• examples of the urethane-based resin include a polyurethane adhesive containing an isocyanate compound and a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance.
• examples of the urethane-based resin include a urethane-based resin containing a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance and a polyol compound.
• a urethane-based resin for example, a urethane-based resin obtained by reacting a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance with moisture in the air and curing the resin can be used.
• the polyol compound it is preferable to use a polyester polyol having a hydroxyl group in a side chain in addition to the terminal hydroxyl group of the repeating unit.
• Examples of the second agent include aliphatic, alicyclic, aromatic, and araliphatic isocyanate compounds.
• isocyanate compounds include hexamethylene diisocyanate (HDI), xylylene diisocyanate (XDI), isophorone diisocyanate (IPDI), hydrogenated XDI (H6XDI), hydrogenated MDI (H12MDI), tolylene diisocyanate (TDI), and diphenylmethane diisocyanate. (MDI), naphthalene diisocyanate (NDI), and the like.
• polyfunctional isocyanate-modified products of one or more of these diisocyanates are also included.
• a polymer for example, a trimer
• a polyisocyanate compound such multimers include adducts, biurets, nurates and the like. Since the adhesive layer 2 is made of urethane-based resin, adhesion, flexibility, and stretchability are enhanced.
• the resin B is not particularly limited as long as it is dissolved in ethyl acetate and included in the adhesive layer 2 in an unreacted state with the resin A.
• Specific examples include acrylic resins, epoxy resins, vinyl resins, polycarbonate resins, polystyrene resins, and silicone resins.
• the resin (for example, epoxy resin) exemplified as resin B is known to react with the resin (urethane resin) exemplified as resin A, but in the present disclosure, resin B reacts with resin A. Therefore, even if the resin B is an epoxy resin, for example, an epoxy resin that does not react with the urethane resin of the resin A is used.
• the resin B does not react with the resin A (does not react) means that the reactive functional group that reacts with the resin A, the first agent (main agent) and the second agent (curing agent) that constitute the resin A is added to the resin. B substantially does not have (not at all or only a little), or poor reactivity, or the first agent (main agent) and the second agent that constitute the resin A Even if the resin B has a reactive functional group that reacts with the agent (curing agent), the reaction rate is low, and the first agent (main agent) and the second agent (curing agent) react first and cure. This means that the resin A and the resin B are generally not crosslinked.
• resin A and the resin B may be the same resin system as long as they satisfy the respective definitions described above.
• the adhesive layer 2 may contain other components as long as they do not impede adhesion, and may contain colorants, thermoplastic elastomers, tackifiers, fillers, and the like. Since the adhesive layer 2 contains a coloring agent, the exterior material for an electric storage device 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.
• the type of pigment is not particularly limited as long as it does not impair the adhesiveness of the adhesive layer 2.
• organic pigments include azo-based, phthalocyanine-based, quinacridone-based, anthraquinone-based, dioxazine-based, indigothioindigo-based, perinone-perylene-based, isoindolenine-based, and benzimidazolone-based pigments.
• pigments include carbon black, titanium oxide, cadmium, lead, chromium oxide, and iron pigments, as well as fine powder of mica and fish scale foil.
• carbon black is preferred, for example, in order to make the external appearance of the exterior material for an electricity storage device black.
• the average particle size of the pigment is not particularly limited, and is, for example, approximately 0.05 to 5 ⁇ m, preferably approximately 0.08 to 2 ⁇ m.
• 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 power storage device exterior material is colored.
• the thickness of the adhesive layer 2 is not particularly limited as long as the base material layer 1 and the barrier layer 3 can be adhered, but is, for example, about 1 ⁇ m or more and about 2 ⁇ m or more. Moreover, the thickness of the adhesive layer 2 is, for example, about 10 ⁇ m or less, or about 5 ⁇ m or less. Further, the preferable range of the thickness of the adhesive layer 2 is about 1 to 10 ⁇ m, about 1 to 5 ⁇ m, about 2 to 10 ⁇ m, and about 2 to 5 ⁇ m.
• the colored layer is a layer provided as necessary between the base layer 1 and the barrier layer 3 (not shown).
• a colored layer may be provided between the base material layer 1 and the adhesive layer 2 and between the adhesive layer 2 and the barrier layer 3 . Further, a colored layer may be provided outside the base material layer 1 . By providing the colored layer, the exterior material for an electricity storage device can be colored.
• the colored layer As the formability improving layer.
• the details of the moldability improving layer are as described above, and when the colored layer is used as the moldability improving layer, it is preferable to form the colored layer with the above-mentioned resin preferable for the moldability improving layer.
• the colored layer can be formed, for example, by applying ink containing a coloring agent to the surface of the base material layer 1 or the surface of the barrier layer 3.
• ink containing a coloring agent such as pigments and dyes can be used as the colorant.
• pigments and dyes can be used as the colorant.
• only one type of colorant may be used, or two or more types may be mixed and used.
• colorant contained in the colored layer are the same as those exemplified in the [Adhesive layer 2] column.
• the barrier layer 3 is a layer that at least prevents permeation of moisture.
• barrier layer 3 for example, a metal foil, a deposited film, a resin layer, etc., having barrier properties can be used.
• vapor-deposited films include metal vapor-deposited films, inorganic oxide vapor-deposited films, and carbon-containing inorganic oxide vapor-deposited films.
• the barrier layer 3 may also include a resin film provided with at least one of these deposited films and resin layers. A plurality of barrier layers 3 may be provided.
• the barrier layer 3 preferably includes a layer made of a metal material.
• the metal material that constitutes the barrier layer 3 include aluminum alloys, stainless steels, titanium steels, and steel plates. When used as metal foils, at least one of aluminum alloy foils and stainless steel foils is included. is preferred.
• the aluminum alloy foil is more preferably a soft aluminum alloy foil made of, for example, an annealed aluminum alloy, from the viewpoint of improving the formability of the exterior material for an electricity storage device, and from the viewpoint of further improving the formability. Therefore, it is preferably an aluminum alloy foil containing iron.
• the iron content is preferably 0.1 to 9.0% by mass, more preferably 0.5 to 2.0% by mass.
• the iron content is 0.1% by mass or more, it is possible to obtain an exterior material for an electricity storage device having superior moldability.
• the iron content is 9.0% by mass or less, it is possible to obtain an exterior material for an electricity storage device that is more excellent in flexibility.
• the soft aluminum alloy foil for example, an aluminum alloy having a composition specified by JIS H4160: 1994 A8021H-O, JIS H4160: 1994 A8079H-O, JIS H4000: 2014 A8021P-O, or JIS H4000: 2014 A8079P-O foil.
• silicon, magnesium, copper, manganese, etc. may be added as needed.
• softening can be performed by annealing treatment or the like.
• stainless steel foils examples include austenitic, ferritic, austenitic/ferritic, martensitic, and precipitation hardened stainless steel foils. Furthermore, from the viewpoint of providing an exterior material for an electricity storage device with excellent formability, the stainless steel foil is preferably made of austenitic stainless steel.
• austenitic stainless steel that constitutes the stainless steel foil
• SUS304 is particularly preferable.
• the thickness of the barrier layer 3 should be at least as long as it functions as a barrier layer that suppresses the intrusion of moisture.
• the thickness of the barrier layer 3 is preferably about 85 ⁇ m or less, more preferably about 50 ⁇ m or less, even more preferably about 40 ⁇ m or less, particularly preferably about 35 ⁇ m or less.
• the thickness of the barrier layer 3 is preferably about 10 ⁇ m or more, more preferably about 20 ⁇ m or more, and more preferably about 25 ⁇ m or more.
• the preferred range of thickness of the barrier layer 3 is about 10 to 85 ⁇ m, about 10 to 50 ⁇ m, about 10 to 40 ⁇ m, about 10 to 35 ⁇ m, about 20 to 85 ⁇ m, about 20 to 50 ⁇ m, about 20 to 40 ⁇ m, 20 to 40 ⁇ m. About 35 ⁇ m, about 25 to 85 ⁇ m, about 25 to 50 ⁇ m, about 25 to 40 ⁇ m, and about 25 to 35 ⁇ m.
• the barrier layer 3 is made of an aluminum alloy foil, the above range is particularly preferred.
• the thickness of the barrier layer 3 is preferably about 45 ⁇ m or more, more preferably about 50 ⁇ m or more, and more preferably about 55 ⁇ m or more. , preferably about 200 ⁇ m or less, more preferably about 85 ⁇ m or less, more preferably about 75 ⁇ m or less, and even more preferably about 70 ⁇ m or less, preferably about 45 to 200 ⁇ m, about 45 to 85 ⁇ m, about 45 to 75 ⁇ m, About 45 to 70 ⁇ m, about 50 to 200 ⁇ m, about 50 to 85 ⁇ m, about 50 to 75 ⁇ m, about 50 to 70 ⁇ m, about 55 to 200 ⁇ m, about 55 to 85 ⁇ m, about 55 to 75 ⁇ m, and about 55 to 70 ⁇ m.
• the high moldability of the electrical storage device exterior material 10 facilitates deep drawing, which can contribute to increasing the capacity of the electrical storage device. Further, when the capacity of the power storage device is increased, the mass of the power storage device increases, but the rigidity of the power storage device exterior material 10 is increased, which contributes to the high sealing performance of the power storage device.
• the thickness of the stainless steel foil is preferably about 60 ⁇ m or less, more preferably about 50 ⁇ m or less, even more preferably about 40 ⁇ m or less, and even more preferably about 30 ⁇ m. Below, it is particularly preferably about 25 ⁇ m or less.
• the thickness of the stainless steel foil is preferably about 10 ⁇ m or more, more preferably about 15 ⁇ m or more.
• the preferable range of the thickness of the stainless steel foil is about 10 to 60 ⁇ m, about 10 to 50 ⁇ m, about 10 to 40 ⁇ m, about 10 to 30 ⁇ m, about 10 to 25 ⁇ m, about 15 to 60 ⁇ m, about 15 to 50 ⁇ m, 15 to 50 ⁇ m.
• About 40 ⁇ m, about 15 to 30 ⁇ m, and about 15 to 25 ⁇ m can be mentioned.
• the barrier layer 3 is a metal foil, it is preferable that at least the surface opposite to the base layer is provided with a corrosion-resistant film in order to prevent dissolution and corrosion.
• the barrier layer 3 may be provided with a corrosion resistant coating on both sides.
• the corrosion-resistant film includes, for example, hydrothermal transformation treatment such as boehmite treatment, chemical conversion treatment, anodizing treatment, plating treatment such as nickel and chromium, and corrosion prevention treatment such as applying a coating agent to the surface of the barrier layer. It is a thin film that provides corrosion resistance (for example, acid resistance, alkali resistance, etc.) to the barrier layer.
• the corrosion-resistant film specifically means a film that improves the acid resistance of the barrier layer (acid-resistant film), a film that improves the alkali resistance of the barrier layer (alkali-resistant film), and the like.
• the treatment for forming the corrosion-resistant film one type may be performed, or two or more types may be used in combination. Also, not only one layer but also multiple layers can be used.
• the hydrothermal transformation treatment and the anodizing treatment are treatments in which the surface of the metal foil is dissolved with a treating agent to form a metal compound having excellent corrosion resistance. These treatments are sometimes included in the definition of chemical conversion treatment.
• the barrier layer 3 includes the corrosion-resistant film.
• the corrosion-resistant coating prevents delamination between the barrier layer (e.g., aluminum alloy foil) and the substrate layer during the molding of the exterior material for power storage devices, and the hydrogen fluoride generated by the reaction between the electrolyte and moisture. , the dissolution and corrosion of the barrier layer surface, especially when the barrier layer is an aluminum alloy foil, the aluminum oxide present on the barrier layer surface is prevented from dissolving and corroding, and the adhesion (wettability) of the barrier layer surface is improved. , and exhibits the effect of preventing delamination between the base material layer and the barrier layer during heat sealing and preventing delamination between the base material layer and the barrier layer during molding.
• the barrier layer e.g., aluminum alloy foil
• Corrosion-resistant coatings formed by chemical conversion treatment are known, and are mainly composed of at least one of phosphates, chromates, fluorides, triazinethiol compounds, and rare earth oxides.
• Corrosion-resistant coatings containing Examples of chemical conversion treatments using phosphate and chromate include chromic acid chromate treatment, phosphoric acid chromate treatment, phosphoric acid-chromate treatment, and chromate treatment.
• Examples of compounds include chromium nitrate, chromium fluoride, chromium sulfate, chromium acetate, chromium oxalate, chromium biphosphate, chromium acetyl acetate, chromium chloride, potassium chromium sulfate, and the like.
• Phosphorus compounds used for these treatments include sodium phosphate, potassium phosphate, ammonium phosphate, polyphosphoric acid, and the like.
• Examples of the chromate treatment include etching chromate treatment, electrolytic chromate treatment, coating-type chromate treatment, etc., and coating-type chromate treatment is preferred.
• the inner layer side surface of the barrier layer (for example, aluminum alloy foil) is first subjected to a well-known method such as an alkali immersion method, an electrolytic cleaning method, an acid cleaning method, an electrolytic acid cleaning method, an acid activation method, or the like.
• metal phosphate such as Cr (chromium) phosphate, Ti (titanium) phosphate, Zr (zirconium) phosphate, Zn (zinc) phosphate is applied to the degreased surface.
• a processing solution mainly composed of a salt and a mixture of these metal salts a processing solution mainly composed of a non-metal phosphate salt and a mixture of these non-metal salts, or a mixture of these and a synthetic resin.
• This is a treatment in which a treatment liquid composed of a mixture is applied by a well-known coating method such as a roll coating method, a gravure printing method, or an immersion method, and then dried.
• Various solvents such as water, alcohol-based solvents, hydrocarbon-based solvents, ketone-based solvents, ester-based solvents, and ether-based solvents can be used as the treatment liquid, and water is preferred.
• the resin component used at this time includes polymers such as phenolic resins and acrylic resins. and the chromate treatment used.
• 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.
• the acrylic resin is polyacrylic acid, acrylic acid methacrylic acid ester copolymer, acrylic acid maleic acid copolymer, acrylic acid styrene copolymer, or derivatives thereof such as sodium salts, ammonium salts, and amine salts. is preferred.
• derivatives of polyacrylic acid such as ammonium salt, sodium salt or amine salt of polyacrylic acid are preferred.
• polyacrylic acid means a polymer of acrylic acid.
• the acrylic resin is preferably a copolymer of acrylic acid and dicarboxylic acid or dicarboxylic anhydride, and the ammonium salt, sodium salt, Alternatively, it is also preferably an amine salt. Only one type of acrylic resin may be used, or two or more types may be mixed and used.
• 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.
• 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.
• 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 straight 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 An alkyl group is mentioned.
• the alkyl groups and hydroxyalkyl groups represented by X, R 1 and R 2 may be the same or different.
• 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.
• the aminated phenol polymer is produced, for example, by polycondensing a phenol compound or naphthol compound and formaldehyde to produce a polymer comprising repeating units represented by the general formula (1) or general formula (3), followed by formaldehyde. and an amine (R 1 R 2 NH) to introduce a functional group (--CH 2 NR 1 R 2 ) into the polymer obtained above.
• An aminated phenol polymer is used individually by 1 type or in mixture of 2 or more types.
• the corrosion-resistant film is formed by a coating-type corrosion prevention treatment in which a coating agent containing at least one selected from the group consisting of rare earth element oxide sol, anionic polymer, and cationic polymer is applied.
• a coating agent containing at least one selected from the group consisting of rare earth element oxide sol, anionic polymer, and cationic polymer is applied.
• the coating agent may further contain phosphoric acid or a phosphate, a cross-linking agent for cross-linking the polymer.
• rare earth element oxide sol rare earth element oxide fine particles (for example, particles having an average particle size of 100 nm or less) are dispersed in a liquid dispersion medium.
• rare earth element oxides include cerium oxide, yttrium oxide, neodymium oxide, and lanthanum oxide, and cerium oxide is preferable from the viewpoint of further improving adhesion.
• the rare earth element oxides contained in the corrosion-resistant coating can be used singly or in combination of two or more.
• various solvents such as water, alcohol solvents, hydrocarbon solvents, ketone solvents, ester solvents, and ether solvents can be used, with water being preferred.
• 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, polyallylamine, or a derivative thereof. , aminated phenols and the like are preferred.
• 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.
• 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.
• the phosphoric acid or phosphate is preferably condensed phosphoric acid or condensed phosphate.
• fine particles of metal oxides such as aluminum oxide, titanium oxide, cerium oxide, and tin oxide, and barium sulfate are dispersed in phosphoric acid, which is applied to the surface of the barrier layer. C. or more, and those formed by performing baking processing are mentioned.
• the corrosion-resistant film may, if necessary, have a laminated structure in which at least one of a cationic polymer and an anionic polymer is further laminated.
• a cationic polymer and anionic polymers include those described above.
• the analysis of the composition of the corrosion-resistant coating can be performed using, for example, time-of-flight secondary ion mass spectrometry.
• the amount of the corrosion-resistant film formed on the surface of the barrier layer 3 in the chemical conversion treatment is not particularly limited. is about 0.5 to 50 mg, preferably about 1.0 to 40 mg in terms of chromium, the phosphorus compound is about 0.5 to 50 mg, preferably about 1.0 to 40 mg in terms of phosphorus, and aminated phenol polymer is contained in a ratio of, for example, about 1.0 to 200 mg, preferably about 5.0 to 150 mg.
• the thickness of the corrosion-resistant coating is not particularly limited, but is preferably about 1 nm to 20 ⁇ m, more preferably 1 nm to 100 nm, from the viewpoint of cohesion of the coating and adhesion to the barrier layer and the heat-sealable resin layer. about 1 nm to 50 nm, more preferably about 1 nm to 50 nm.
• the thickness of the corrosion-resistant film can be measured by observation with a transmission electron microscope, or by a combination of observation with a transmission electron microscope and energy dispersive X-ray spectroscopy or electron beam energy loss spectroscopy.
• secondary ions composed of Ce, P and O for example, at least one of Ce 2 PO 4 + and CePO 4 ⁇ species
• secondary ions composed of Cr, P, and O eg, at least one of CrPO 2 + and CrPO 4 ⁇
• Chemical conversion treatment involves applying a solution containing a compound used to form a corrosion-resistant film to the surface of the barrier layer by a bar coating method, roll coating method, gravure coating method, immersion method, etc. is carried out by heating so that the temperature is about 70 to 200°C.
• 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.
• an acid degreasing agent obtained by dissolving a fluorine-containing compound in an inorganic acid for degreasing treatment it is possible to form not only the degreasing effect of the metal foil but also the passive metal fluoride. In such cases, only degreasing treatment may be performed.
• the heat-fusible resin layer 4 corresponds to the innermost layer, and has the function of sealing the power storage device element by heat-sealing the heat-fusible resin layers to each other when assembling the power storage device. It is a layer (sealant layer) that exhibits
• the heat-fusible resin layer 4 may be used as a formability improving layer.
• the details of the moldability improving layer are as described above. is preferably formed.
• the heat-fusible resin layer 4 is used as a moldability-enhancing layer, the stress can be dispersed by the heat-fusible resin layer 4, so cracks are suppressed without applying local force to the barrier layer 3 during molding. It is possible to improve moldability.
• the heat-fusible resin layer is multi-layered, if the innermost heat-fusible resin layer is not used as a moldability improving layer, and at least one layer other than the innermost layer is used as a moldability improving layer, high sealing performance can be achieved. Moldability can be improved while being provided.
• the resin constituting the heat-fusible resin layer 4 is not particularly limited as long as it is heat-fusible, but resins containing polyolefin skeletons such as polyolefins and acid-modified polyolefins are preferred.
• the inclusion of a polyolefin skeleton in the resin constituting the heat-fusible resin layer 4 can be analyzed by, for example, infrared spectroscopy, gas chromatography-mass spectrometry, or the like. Further, when the resin constituting the heat-fusible resin layer 4 is analyzed by infrared spectroscopy, it is preferable that a peak derived from maleic anhydride is detected.
• peaks derived from maleic anhydride are detected near wavenumbers of 1760 cm ⁇ 1 and 1780 cm ⁇ 1 .
• the heat-fusible resin layer 4 is a layer composed of maleic anhydride-modified polyolefin
• a peak derived from maleic anhydride is detected when measured by infrared spectroscopy.
• 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.
• the heat-fusible resin layer 4 preferably contains a resin having a polyolefin skeleton as a main component, more preferably contains polyolefin as a main component, and further preferably contains polypropylene as a main component.
• the main component is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, more preferably 70% by mass or more, more preferably, among the resin components contained in the heat-fusible resin layer 4. means that the resin component is 80% by mass or more, more preferably 90% by mass or more, more preferably 95% by mass or more, still more preferably 98% by mass or more, and still more preferably 99% by mass or more.
• the heat-fusible resin layer 4 containing polypropylene as a main component means that the content of polypropylene among the resin components contained in the heat-fusible resin layer 4 is, for example, 50% by mass or more, preferably 60% by mass. % or more, more preferably 70 mass % or more, more preferably 80 mass % or more, still more preferably 90 mass % or more, still more preferably 95 mass % or more, still more preferably 98 mass % or more, still more preferably 99 mass % or more means that
• polyolefins include polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; ethylene- ⁇ -olefin copolymers; block copolymers of ethylene), random copolymers of polypropylene (for example, random copolymers of propylene and ethylene); propylene- ⁇ -olefin copolymers; ethylene-butene-propylene terpolymers; Among these, polypropylene is preferred.
• the polyolefin resin is a copolymer, it may be a block copolymer or a random copolymer. These polyolefin resins may be used alone or in combination of two or more.
• the polyolefin may be a cyclic polyolefin.
• a cyclic polyolefin is a copolymer of an olefin and a cyclic monomer.
• the olefin which is a constituent monomer of the cyclic polyolefin, include ethylene, propylene, 4-methyl-1-pentene, styrene, butadiene, and isoprene. be done.
• Examples of cyclic monomers constituting cyclic polyolefins include cyclic alkenes such as norbornene; cyclic dienes such as cyclopentadiene, dicyclopentadiene, cyclohexadiene and norbornadiene. Among these, cyclic alkenes are preferred, and norbornene is more preferred.
• the polyolefin may be an acid-modified polyolefin.
• Acid-modified polyolefin is a polymer modified by block polymerization or graft polymerization of polyolefin with an acid component.
• the acid-modified polyolefin the above polyolefin, a copolymer obtained by copolymerizing the above polyolefin with a polar molecule such as acrylic acid or methacrylic acid, or a polymer such as crosslinked polyolefin can be used.
• acid components used for acid modification include carboxylic acids such as maleic acid, acrylic acid, itaconic acid, crotonic acid, maleic anhydride and itaconic anhydride, and anhydrides thereof.
• the acid-modified polyolefin may be an acid-modified cyclic polyolefin.
• the acid-modified cyclic polyolefin is a polymer obtained by copolymerizing a part of the monomers constituting the cyclic polyolefin in place of the acid component, or by block-polymerizing or graft-polymerizing the acid component to the cyclic polyolefin. be.
• the acid-modified cyclic polyolefin is the same as described above.
• the acid component used for acid modification is the same as the acid component used for modification of polyolefin.
• Preferable acid-modified polyolefins include polyolefins modified with carboxylic acid or its anhydride, polypropylene modified with carboxylic acid or its anhydride, maleic anhydride-modified polyolefin, and maleic anhydride-modified polypropylene.
• the heat-fusible resin layer 4 may be formed of one type of resin alone, or may be formed of a blend polymer in which two or more types of resin are combined. Further, the heat-fusible resin layer 4 may be formed of only one layer, or may be formed of two or more layers of the same or different resins.
• the heat-fusible resin layer 4 may contain a lubricant or the like as necessary.
• a lubricant is not particularly limited, and known lubricants can be used. Lubricants may be used singly or in combination of two or more.
• the lubricant is not particularly limited, but preferably includes an amide-based lubricant. Specific examples of the lubricant include those exemplified for the base material layer 1 .
• the lubricants may be used singly or in combination of two or more, preferably in combination of two or more.
• the surface and the inside of the heat-fusible resin layer 4 contains a lubricant.
• the lubricant is not particularly limited, but preferably includes an amide-based lubricant.
• Specific examples of amide lubricants include saturated fatty acid amides, unsaturated fatty acid amides, substituted amides, methylolamides, saturated fatty acid bisamides, unsaturated fatty acid bisamides, fatty acid ester amides, and aromatic bisamides.
• saturated fatty acid amides include lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, and hydroxystearic acid amide.
• unsaturated fatty acid amides include oleic acid amide and erucic acid amide.
• 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.
• methylolamide include methylol stearamide.
• 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.
• 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.
• fatty acid ester amides include stearamide ethyl stearate.
• aromatic bisamide include m-xylylenebisstearic acid amide, m-xylylenebishydroxystearic acid amide, N,N'-distearyl isophthalic acid amide and the like.
• the lubricants may be used singly or in combination of two or more, preferably in combination of two or more.
• the amount of the lubricant is not particularly limited, but from the viewpoint of improving the moldability of the exterior material for an electricity storage device, it is preferably about 1 mg/m 2 or more, More preferably about 3 mg/m 2 or more, still more preferably about 5 mg/m 2 or more, still more preferably about 10 mg/m 2 or more, still more preferably about 15 mg/m 2 or more, and more preferably about 50 mg/m 2 or more 2 or less, more preferably about 40 mg/m 2 or less.
• Preferred ranges are about 1 to 50 mg/m 2 , about 1 to 40 mg/m 2 , about 3 to 50 mg/m 2 , and 3 to 40 mg/m 2 . about 5 to 50 mg/m 2 , about 5 to 40 mg/m 2 , about 10 to 50 mg/m 2 , about 10 to 40 mg/m 2 , about 15 to 50 mg/m 2 , about 15 to 40 mg/m 2 mentioned.
• the amount of the lubricant is not particularly limited, but from the viewpoint of improving the moldability of the exterior material for an electricity storage device, it is preferably about 100 ppm or more, more preferably about 100 ppm or more.
• about 300 ppm or more, more preferably about 500 ppm or more, preferably about 3000 ppm or less, more preferably about 2000 ppm or less, preferably about 100 to 3000 ppm, about 100 to 2000 ppm, about 300 to 3000 ppm, About 300 to 2000 ppm, about 500 to 3000 ppm, and about 500 to 2000 ppm can be mentioned.
• the amount of the lubricants is the total amount of the lubricants.
• the amount of the first type of lubricant is not particularly limited. It is preferably about 100 ppm or more, more preferably about 300 ppm or more, still more preferably about 500 ppm or more, and preferably about 3000 ppm or less, more preferably about 2000 ppm or less. about 2000 ppm, about 300 to 3000 ppm, about 300 to 2000 ppm, about 500 to 3000 ppm, and about 500 to 2000 ppm.
• the amount of the second type of lubricant is not particularly limited, but is preferably about 50 ppm or more, more preferably about 100 ppm or more, and still more preferably about 200 ppm or more from the viewpoint of improving the moldability of the exterior material for an electric storage device. , Also preferably about 1500 ppm or less, more preferably about 1000 ppm or less. About 1000 ppm is mentioned.
• the lubricant present on the surface of the heat-fusible resin layer 4 may be obtained by exuding the lubricant contained in the resin constituting the heat-fusible resin layer 4 .
• the surface may be coated with a lubricant.
• the thickness of the heat-fusible resin layer 4 is not particularly limited as long as the heat-fusible resin layers are heat-sealed to each other to exhibit the function of sealing the electricity storage device element, but for example, it is about 100 ⁇ m or less, preferably about 100 ⁇ m or less. About 85 ⁇ m or less, more preferably about 15 to 85 ⁇ m.
• the thickness of the heat-fusible resin layer 4 is preferably about 85 ⁇ m or less, more preferably about 15 to 45 ⁇ m.
• the thickness of the heat-fusible resin layer 4 is preferably about 20 ⁇ m or more, more preferably 35 to 85 ⁇ m. degree.
• the adhesive layer 5 is provided between the barrier layer 3 (or the corrosion-resistant film) and the heat-fusible resin layer 4 as necessary in order to firmly bond them. It is a layer that can be
• the adhesive layer 5 is used as a formability improving layer.
• the details of the moldability improving layer are as described above, and when the adhesive layer 5 is used as the moldability improving layer, it is preferable to form the adhesive layer 5 from the above-described resin preferable for the moldability improving layer.
• the adhesive layer 5 is used as a moldability improving layer, the elongation of the base material layer 1 caused by molding and the Since it is possible to follow both the elongation of the barrier layer 3 and relax the stress, the formability is improved.
• the adhesive layer 5 is made of a resin that can bond the barrier layer 3 and the heat-fusible resin layer 4 together.
• the resin used for forming the adhesive layer 5 for example, the same adhesives as those exemplified for the adhesive layer 2 can be used.
• the resin used for forming the adhesive layer 5 contains a polyolefin skeleton. Polyolefins and acid-modified polyolefins exemplified for the resin layer 4 can be used.
• the adhesive layer 5 preferably contains an acid-modified polyolefin.
• Acid-modified components include dicarboxylic acids such as maleic acid, itaconic acid, succinic acid and adipic acid, their anhydrides, acrylic acid and methacrylic acid. Maleic acid is most preferred.
• the olefin component is preferably a polypropylene-based resin, and the adhesive layer 5 most preferably contains maleic anhydride-modified polypropylene.
• the adhesive layer 5 When the resin used to form the adhesive layer 5 contains a polyolefin skeleton, the adhesive layer 5 preferably contains a resin containing a polyolefin skeleton as a main component, and contains an acid-modified polyolefin as a main component. More preferably, it contains acid-modified polypropylene as a main component.
• the main component means that the resin component contained in the adhesive layer 5 has a content of, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, and further preferably 80% by mass.
• the adhesive layer 5 containing acid-modified polypropylene as a main component means that the content of acid-modified polypropylene among the resin components contained in the adhesive layer 5 is, for example, 50% by mass or more, preferably 60% by mass or more, or more. It is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, still more preferably 95% by mass or more, still more preferably 98% by mass or more, further preferably 99% by mass or more. means.
• 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.
• the fact that the resin constituting the adhesive layer 5 contains an acid-modified polyolefin means that, for example, when the maleic anhydride-modified polyolefin is measured by infrared spectroscopy , anhydrous A peak derived from maleic acid is detected. 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.
• the adhesive layer 5 is made of a resin composition containing an acid-modified polyolefin and a curing agent.
• a cured product is more preferred.
• Preferred examples of the acid-modified polyolefin include those mentioned above.
• the adhesive layer 5 is a cured product of a resin composition containing acid-modified polyolefin and at least one selected from the group consisting of a compound having an isocyanate group, a compound having an oxazoline group, and a compound having an epoxy group.
• a cured product of a resin composition containing an acid-modified polyolefin and at least one selected from the group consisting of a compound having an isocyanate group and a compound having an epoxy group is particularly preferred.
• the adhesive layer 5 preferably contains at least one selected from the group consisting of polyurethane, polyester, and epoxy resin, and more preferably contains polyurethane and epoxy resin.
• an ester resin produced by a reaction between an epoxy group and a maleic anhydride group, and an amide ester resin produced by a reaction between an oxazoline group and a maleic anhydride group are preferable.
• the adhesive layer 5 contains an isocyanate group-containing compound, an oxazoline group-containing compound, or an unreacted product of a curing agent such as an epoxy resin
• the presence of the unreacted product can be detected by, for example, infrared spectroscopy, It can be confirmed by a method selected from Raman spectroscopy, time-of-flight secondary ion mass spectrometry (TOF-SIMS), and the like.
• the adhesive layer 5 contains at least It is preferably a cured product of a resin composition containing one curing agent.
• the curing agent having a heterocyclic ring includes, for example, a curing agent having an oxazoline group, a curing agent having an epoxy group, and the like.
• the curing agent having a C ⁇ N bond includes a curing agent having an oxazoline group, a curing agent having an isocyanate group, and the like.
• the curing agent having a C—O—C bond includes a curing agent having an oxazoline group, a curing agent having an epoxy group, and the like.
• the adhesive layer 5 is a cured product of a resin composition containing these curing agents, for example, gas chromatography mass spectrometry (GCMS), infrared spectroscopy (IR), time-of-flight secondary ion mass spectrometry (TOF -SIMS) and X-ray photoelectron spectroscopy (XPS).
• GCMS gas chromatography mass spectrometry
• IR infrared spectroscopy
• TOF -SIMS time-of-flight secondary ion mass spectrometry
• XPS X-ray photoelectron spectroscopy
• the compound having an isocyanate group is not particularly limited, but from the viewpoint of effectively increasing the adhesion between the barrier layer 3 and the adhesive layer 5, polyfunctional isocyanate compounds are preferred.
• the polyfunctional isocyanate compound is not particularly limited as long as it is a compound having two or more isocyanate groups.
• Specific examples of polyfunctional isocyanate curing agents include pentane diisocyanate (PDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymerization and nurate compounds, mixtures thereof, copolymers with other polymers, and the like.
• adducts, biurets, isocyanurates and the like are included.
• the content of the compound having an isocyanate group in the adhesive layer 5 is preferably in the range of 0.1 to 50% by mass, more preferably 0.5 to 40% by mass in the resin composition constituting the adhesive layer 5. A range is more preferred. Thereby, the adhesion between the barrier layer 3 and the adhesive layer 5 can be effectively improved.
• the compound having an oxazoline group is not particularly limited as long as it is a compound having an oxazoline skeleton.
• Specific examples of compounds having an oxazoline group include those having a polystyrene main chain and those having an acrylic main chain.
• the Epocross series by Nippon Shokubai Co., Ltd. etc. are mentioned, for example.
• the ratio of the compound having an oxazoline group in the adhesive layer 5 is preferably in the range of 0.1 to 50% by mass, more preferably 0.5 to 40% by mass, in the resin composition constituting the adhesive layer 5. is more preferable. Thereby, the adhesion between the barrier layer 3 and the adhesive layer 5 can be effectively improved.
• Examples of compounds having an epoxy group include epoxy resins.
• the epoxy resin is not particularly limited as long as it is a resin capable of forming a crosslinked structure with epoxy groups present in the molecule, and known epoxy resins can be used.
• the weight average molecular weight of the epoxy resin is preferably about 50 to 2000, more preferably about 100 to 1000, still more preferably about 200 to 800.
• the weight average molecular weight of the epoxy resin is a value measured by gel permeation chromatography (GPC) under conditions using polystyrene as a standard sample.
• epoxy resins include glycidyl ether derivatives of trimethylolpropane, bisphenol A diglycidyl ether, modified bisphenol A diglycidyl ether, bisphenol F-type glycidyl ether, novolac glycidyl ether, glycerin polyglycidyl ether, polyglycerin polyglycidyl ether, and the like. is mentioned.
• An epoxy resin may be used individually by 1 type, and may be used in combination of 2 or more types.
• the proportion of the epoxy resin in the adhesive layer 5 is preferably in the range of 0.1 to 50% by mass, more preferably in the range of 0.5 to 40% by mass, in the resin composition constituting the adhesive layer 5. is more preferred. Thereby, the adhesion between the barrier layer 3 and the adhesive layer 5 can be effectively improved.
• the polyurethane is not particularly limited, and known polyurethanes can be used.
• the adhesive layer 5 may be, for example, a cured product of two-component curing type polyurethane.
• the proportion of polyurethane in the adhesive layer 5 is preferably in the range of 0.1 to 50% by mass, more preferably in the range of 0.5 to 40% by mass, in the resin composition constituting the adhesive layer 5. more preferred.
• the adhesion between the barrier layer 3 and the adhesive layer 5 can be effectively enhanced in an atmosphere containing a component that induces corrosion of the barrier layer, such as an electrolytic solution.
• the adhesive layer 5 is a cured product of a resin composition containing at least one selected from the group consisting of a compound having an isocyanate group, a compound having an oxazoline group, and an epoxy resin, and the acid-modified polyolefin.
• the acid-modified polyolefin functions as a main agent, and the compound having an isocyanate group, the compound having an oxazoline group, and the compound having an epoxy group each function as a curing agent.
• the adhesive layer 5 may contain a modifier having a carbodiimide group.
• a pre-formed resin film may be used as the adhesive layer 5 when the adhesive layer 5 is laminated with the barrier layer 3, the heat-fusible resin layer 4, and the like to manufacture the power storage device exterior material 10 of the present disclosure.
• the adhesive layer 5 formed of the resin film is formed by extruding or coating the heat-fusible resin forming the adhesive layer 5 into a film on the surface of the barrier layer 3, the heat-fusible resin layer 4, or the like. may be
• the thickness of the adhesive layer 5 is preferably about 50 ⁇ m or less, about 40 ⁇ m or less, about 30 ⁇ m or less, about 20 ⁇ m or less, or about 5 ⁇ m or less. Also, the thickness of the adhesive layer 5 is preferably about 0.1 ⁇ m or more and about 0.5 ⁇ m or more.
• the thickness range of the adhesive layer 5 is preferably about 0.1 to 50 ⁇ m, about 0.1 to 40 ⁇ m, about 0.1 to 30 ⁇ m, about 0.1 to 20 ⁇ m, and about 0.1 to 5 ⁇ m. , about 0.5 to 50 ⁇ m, about 0.5 to 40 ⁇ m, about 0.5 to 30 ⁇ m, about 0.5 to 20 ⁇ m, and about 0.5 to 5 ⁇ m.
• the thickness is preferably about 1 to 10 ⁇ m, more preferably about 1 to 5 ⁇ m.
• the thickness is preferably about 2 to 50 ⁇ m, more preferably about 10 to 40 ⁇ m.
• the exterior material for an electricity storage device of the present disclosure is provided on the base layer 1 (base layer 1 (the side opposite to the barrier layer 3) may be provided with a surface coating layer 6.
• the surface coating layer 6 is a layer positioned on the outermost layer side of the exterior material for an electricity storage device when an electricity storage device is assembled using the exterior material for an electricity storage device.
• the surface coating layer 6 may be a moldability improving layer.
• the details of the moldability improving layer are as described above, and when the surface coating layer 6 is used as the moldability improving layer, it is preferable to form the surface coating layer 6 with the above-mentioned preferable resin for the moldability improving layer. .
• stress can be dispersed by the surface coating layer 6, so that the base material layer 1 and the barrier layer 3 are not subjected to local force during molding, and the base material cracks. Cracks can be suppressed and formability is improved.
• the surface coating layer 6 examples include resins such as polyvinylidene chloride, polyester, polyamide, epoxy resin, acrylic resin, fluororesin, polyurethane, silicon resin, phenolic resin, and modified products of these resins. Copolymers of these resins or modified copolymers may also be used. Furthermore, it may be a mixture of these resins.
• the resin is preferably a curable resin. That is, the surface coating layer 6 is preferably made of a cured product of a resin composition containing a curable resin.
• the resin forming the surface coating layer 6 is a curable resin
• the resin may be either a one-liquid curable type or a two-liquid curable type, preferably the two-liquid curable type.
• the two-liquid curing resin include two-liquid curing polyurethane, two-liquid curing polyester, and two-liquid curing epoxy resin. Among these, two-liquid curable polyurethane is preferred.
• two-liquid curable polyurethanes include polyurethanes containing a first agent containing a polyol compound and a second agent containing an isocyanate compound.
• Preferred examples include a two-component curing type polyurethane in which a polyol such as polyester polyol, polyether polyol, or acrylic polyol is used as the first agent and an aromatic or aliphatic polyisocyanate is used as the second agent.
• polyurethane include polyurethane containing a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance and an isocyanate compound.
• polyurethane examples include polyurethane containing a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance and a polyol compound.
• polyurethanes examples include polyurethanes obtained by reacting a polyurethane compound obtained by reacting a polyol compound and an isocyanate compound in advance with moisture in the air and the like to cure the compound.
• the polyol compound it is preferable to use a polyester polyol having a hydroxyl group in a side chain in addition to the terminal hydroxyl group of the repeating unit.
• the second agent examples include aliphatic, alicyclic, aromatic, and araliphatic isocyanate compounds.
• isocyanate compounds include hexamethylene diisocyanate (HDI), xylylene diisocyanate (XDI), isophorone diisocyanate (IPDI), hydrogenated XDI (H6XDI), hydrogenated MDI (H12MDI), tolylene diisocyanate (TDI), and diphenylmethane diisocyanate. (MDI), naphthalene diisocyanate (NDI), and the like.
• polyfunctional isocyanate-modified products of one or more of these diisocyanates are also included.
• a polymer for example, a trimer
• Such multimers include adducts, biurets, nurates and the like.
• the aliphatic isocyanate compound refers to an isocyanate having an aliphatic group and no aromatic ring
• the alicyclic isocyanate compound refers to an isocyanate having an alicyclic hydrocarbon group
• the aromatic isocyanate compound refers to an isocyanate having an aromatic ring. Since the surface coating layer 6 is made of polyurethane, the exterior material for an electric storage device is endowed with excellent electrolyte resistance.
• At least one of the surface and the inside of the surface coating layer 6 may be coated with the above-described lubricant or anti-rust agent as necessary depending on the functionality to be provided on the surface coating layer 6 and its surface.
• Additives such as blocking agents, matting agents, flame retardants, antioxidants, tackifiers and antistatic agents may be included.
• the additive include fine particles having an average particle size of about 0.5 nm to 5 ⁇ m. The average particle size of the additive is the median size measured with a laser diffraction/scattering particle size distribution analyzer.
• Additives may be either inorganic or organic.
• shape of the additive is not particularly limited, and examples thereof include spherical, fibrous, plate-like, amorphous, and scaly shapes.
• additives include talc, silica, graphite, kaolin, montmorillonite, mica, hydrotalcite, silica gel, zeolite, aluminum hydroxide, magnesium hydroxide, zinc oxide, magnesium oxide, aluminum oxide, neodymium oxide, and antimony oxide.
• Additives may be used singly or in combination of two or more.
• silica, barium sulfate, and titanium oxide are preferred from the viewpoint of dispersion stability and cost.
• the additive may be subjected to various surface treatments such as insulation treatment and high-dispersion treatment.
• the method of forming the surface coating layer 6 is not particularly limited, and for example, a method of applying a resin for forming the surface coating layer 6 can be used. When adding additives to the surface coating layer 6, a resin mixed with the additives may be applied.
• the thickness of the surface coating layer 6 is not particularly limited as long as the above functions of the surface coating layer 6 are exhibited.
• Method for producing an exterior material for an electricity storage device is not particularly limited as long as a laminate obtained by laminating each layer included in the exterior material for an electricity storage device of the present invention is obtained.
• a method including a step of laminating the layer 1, the barrier layer 3, and the heat-fusible resin layer 4 in this order may be mentioned. That is, in the method for manufacturing an exterior material for an electricity storage device according to the first aspect of the present disclosure, a laminate in which at least a base layer, a barrier layer, and a heat-fusible resin layer are laminated in order from the outside is prepared.
• At least one layer included in the laminate constitutes a moldability improving layer
• the moldability improving layer comprises a resin A that is insoluble in ethyl acetate, and a resin A that is soluble in ethyl acetate, and , and a resin B that is unreacted with the resin A
• the moldability improving layer has a resin A content of 43% by mass or more and a resin B content of 4% by mass or more and 57% by mass. It is below.
• a laminate in which at least a base layer, a barrier layer, and a heat-fusible resin layer are laminated in this order from the outside is provided.
• At least one layer included in the laminate constitutes a moldability-improving layer having a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate.
• at least the base layer, the adhesive layer, the barrier layer, and the heat-fusible resin layer are arranged in this order.
• the adhesive layer has a peak molecular weight of 35,000 or less in a differential molecular weight distribution curve measured using gel permeation chromatography.
• 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.
• the laminate A is formed by applying an adhesive used for forming the adhesive layer 2 on the substrate layer 1 or on the barrier layer 3 whose surface is chemically treated as necessary, by a gravure coating method, It can be performed by 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.
• the heat-fusible resin layer 4 is laminated on the barrier layer 3 of the laminate A.
• the heat-fusible resin layer 4 is laminated on the barrier layer 3 of the laminate A by a method such as thermal lamination or extrusion lamination. do it.
• the adhesive layer 5 is provided between the barrier layer 3 and the heat-fusible resin layer 4, the adhesive layer 5 and the heat-fusible resin layer 4 are formed by, for example, (1) extrusion lamination, (2) Lamination can be performed by a thermal lamination method, (3) a sandwich lamination method, (4) a dry lamination method, or the like.
• extrusion lamination method for example, a method of laminating the adhesive layer 5 and the heat-fusible resin layer 4 on the barrier layer 3 of the laminate A by extrusion (co-extrusion lamination method, tandem lamination method). etc.
• (2) thermal lamination method for example, a method of separately forming a laminate in which the adhesive layer 5 and the heat-fusible resin layer 4 are laminated, and laminating this on the barrier layer 3 of the laminate A; , a method of forming a laminate in which an adhesive layer 5 is laminated on the barrier layer 3 of the laminate A, and laminating this with the heat-fusible resin layer 4, and the like.
• the (3) sandwich lamination method for example, while pouring the melted adhesive layer 5 between the barrier layer 3 of the laminate A and the heat-fusible resin layer 4 that has been formed into a sheet in advance, , a method of bonding the laminate A and the heat-fusible resin layer 4 with the adhesive layer 5 interposed therebetween, and the like.
• the dry lamination method (4) for example, the barrier layer 3 of the laminate A is coated with a solution of an adhesive for forming the adhesive layer 5, followed by drying, or by baking. Then, a heat-fusible resin layer 4 formed in a sheet form in advance is laminated on the adhesive layer 5 .
• the surface coating layer 6 When the surface coating layer 6 is provided, 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.
• the barrier layer 3 may be formed on the surface of the substrate layer 1 opposite to the surface coating layer 6 .
• each layer constituting the laminate may be subjected to surface activation treatment such as corona treatment, blasting treatment, oxidation treatment, and ozone treatment to improve processability as necessary.
• surface activation treatment such as corona treatment, blasting treatment, oxidation treatment, and ozone treatment.
• the printability of the ink onto the surface of the substrate layer 1 can be improved.
• the power storage device exterior material of the present disclosure is used in a packaging body for sealingly housing power storage device elements such as a positive electrode, a negative electrode, and an electrolyte. That is, an electricity storage device can be obtained by housing an electricity storage device element including at least a positive electrode, a negative electrode, and an electrolyte in a package formed by the electricity storage device exterior material of the present disclosure.
• an electricity storage device element having at least a positive electrode, a negative electrode, and an electrolyte is placed in the exterior material for an electricity storage device of the present disclosure in a state in which the metal terminals connected to the positive electrode and the negative electrode protrude outward.
• covering the periphery of the electricity storage device element so as to form a flange portion (area where the heat-fusible resin layers contact each other), and heat-sealing the heat-fusible resin layers of the flange portion to seal. provides an electricity storage device using an exterior material for an electricity storage device.
• the heat-fusible resin portion of the electricity storage device exterior material of the present disclosure is on the inside (surface in contact with the electricity storage device element ) to form a package.
• the heat-fusible resin layers of the two exterior materials for an electricity storage device may be placed facing each other, and the peripheral edges of the exterior materials for an electricity storage device that have been stacked may be heat-sealed to form a package.
• one power storage device exterior material may be folded back and overlapped, and the peripheral edges may be heat-sealed to form a package. In the case of folding and stacking, as shown in the example shown in FIG.
• the sides other than the folded sides may be heat-sealed to form a package body by three-side sealing, or the packages may be folded back so as to form a flange portion.
• a heat-sealed portion is formed by wrapping the power storage device exterior material around the power storage device element and sealing the heat-fusible resin layers to close the openings at both ends.
• a lid or the like may be arranged as shown in FIG.
• the lid body can be formed of, for example, a resin molded product, a metal molded product, an exterior material for an electric storage device, or the like.
• a recess for housing the power storage device element may be formed by deep drawing or stretch forming.
• one power storage device exterior material may be provided with a recess and the other power storage device exterior material may not be provided with a recess, or the other power storage device exterior material may also have a recess. may be provided.
• the power storage device exterior material of the present disclosure can be suitably used for power storage devices such as batteries (including capacitors, capacitors, etc.).
• the exterior material for an electricity storage device of the present disclosure may be used for either a primary battery or a secondary battery, it is preferably used for a secondary battery.
• the type of secondary battery to which the power storage device exterior material of the present disclosure is applied is not particularly limited. , all-resin batteries, lead-acid batteries, nickel-hydrogen batteries, nickel-cadmium batteries, nickel-iron batteries, nickel-zinc batteries, silver-zinc oxide batteries, metal-air batteries, polyvalent cation batteries, capacitors, capacitors, etc. .
• lithium ion batteries and lithium ion polymer batteries can be mentioned as suitable targets for application of the power storage device exterior material of the present disclosure.
• Resin composition for use in exterior material for power storage device comprises, in order from the outside, at least a base layer, a barrier layer, and a heat-sealable layer.
• a resin composition for use in a power storage device exterior material composed of a laminate having a flexible resin layer the resin composition comprising a resin A that is insoluble in ethyl acetate, and a resin A that is soluble in ethyl acetate and
• the resin composition contains 43% by mass or more of the resin A and 4% by mass or more and 57% by mass or less of the resin B. is. That is, it is a resin composition used for forming the moldability improving layer of the exterior material for an electricity storage device according to the first aspect.
• the resin composition for use in the exterior material for an electricity storage device according to the second embodiment is composed of a laminate including, in order from the outside, at least a substrate layer, a barrier layer, and a heat-fusible resin layer.
• a resin composition for use as an exterior material for an electricity storage device wherein the resin composition has a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate. That is, it is a resin composition used for forming the moldability improving layer of the exterior material for an electricity storage device according to the second aspect.
• the resin that forms the moldability improving layer is as described in the [Moldability improving layer] section.
• Resin A-1 A two-liquid type polyurethane adhesive using a polyester polyol and an aromatic isocyanate compound.
• Resin A-2 A resin having a glass transition temperature higher than that of resin A-1, and is a two-liquid type polyurethane adhesive using a polyester polyol and an aromatic isocyanate compound.
• Resin A-3 This is the same resin as Resin A-2, and is a two-liquid type polyurethane adhesive in which carbon black is blended with polyester polyol and an aromatic isocyanate compound.
• Resin B-1 A resin obtained by slightly mixing epoxy resin 1, which hardly reacts with resin A-1, with epoxy resin 2, which hardly reacts with resin A-1.
• Resin B-2 A resin different from the resin B-1 and having a structure similar to that of the epoxy resin 1, which hardly reacts with the resin A-1.
• Resin B-3 A resin different from the resins B-1 and B-2 and having a structure similar to that of the epoxy resin 2, which hardly reacts with the resin A-1.
• Resin B-4 A resin different from the resins B-1, B-2 and B-3, and an epoxy resin that reacts with the resin A-1.
• Examples 1A-7A and Comparative Examples 1A-3A An oriented polyethylene terephthalate (PET) film (12 ⁇ m thick) and an oriented nylon (ONy) film (15 ⁇ m thick) were prepared as base layers. Using a two-component urethane adhesive (polyol compound and aromatic isocyanate compound), the thickness of the adhesive layer (DL: formed by a dry lamination method) after curing is 3 ⁇ m, and the PET film and the ONy film are bonded. were adhered via an adhesive layer. Also, an aluminum foil (JIS H4160:1994 A8021H-O (thickness: 40 ⁇ m)) was prepared as a barrier layer.
• JIS H4160:1994 A8021H-O thickness: 40 ⁇ m
• the resin A-1 and the resins B-1 to B-4 described above are mixed and bonded so that the adhesive forming the adhesive layer has the composition (mass ratio) shown in Table 1A. formulations were prepared.
• an aluminum foil and a base layer are laminated by a dry lamination method so that the adhesive layer has a thickness of 3 ⁇ m after curing, and then aging treatment is performed.
• a laminate of substrate layer/adhesive layer/barrier layer was produced by carrying out. Both sides of the aluminum foil are chemically treated.
• a treatment solution consisting of phenolic resin, fluorochromium compound, and phosphoric acid was applied to both sides of the aluminum foil by a roll coating method so that the coating amount of chromium was 10 mg/m 2 (dry mass). It was carried out by coating and baking.
• Examples 8A-11A and Comparative Example 4A The above-described resin A-2 and resin B-2 are mixed so that the adhesive forming the adhesive layer has the composition (mass ratio) shown in Table 2A to prepare an adhesive. Exterior materials for power storage devices were obtained in the same manner as in Examples 1A to 7A and Comparative Example 1A, except that layers were formed. The laminate structure of the exterior material for an electricity storage device is as shown in Table 2A.
• Examples 12A-14A and Comparative Example 5A An oriented nylon (ONy) film (thickness: 15 ⁇ m) was prepared as a substrate layer. Also, an aluminum foil (JIS H4160:1994 A8021H-O (thickness: 35 ⁇ m)) was prepared as a barrier layer. Next, the above resin A-3 and resin B-3 were mixed so that the adhesive forming the adhesive layer had the composition (mass ratio) shown in Table 3A to prepare an adhesive. . Next, using the obtained adhesive, an aluminum foil and a base layer (on the ONy film side) are laminated by a dry lamination method so that the adhesive layer has a thickness of 3 ⁇ m after curing, and then aging treatment is performed.
• a laminate of substrate layer/adhesive layer/barrier layer was produced by carrying out. Both sides of the aluminum foil are chemically treated. In the chemical conversion treatment of the aluminum foil, a treatment solution consisting of phenolic resin, fluorochromium compound, and phosphoric acid was applied to both sides of the aluminum foil by a roll coating method so that the coating amount of chromium was 10 mg/m 2 (dry mass). It was carried out by coating and baking.
• Adhesive is applied to a Si-coated PET film (release PET) to a thickness of about 90 ⁇ m to 100 ⁇ m, cured, and then peeled off from the release PET so that the total volume is 30 to 40 mm 3 .
• the mass (g) was measured with a scale capable of measuring to four decimal places (mass of the adhesive layer before immersion).
• a solvent ethyl acetate was placed in a screw bottle so that the adhesive single film whose mass had already been measured was immersed in the solvent, and stored in an environment of 25° C. for 12 hours or more.
• Each electrical storage device exterior material was cut into a rectangle having a length (MD) of 80 mm and a width (TD) of 120 mm to obtain a test sample.
• the MD of the power storage device exterior material corresponds to the rolling direction (RD) of the aluminum alloy foil
• the TD of the power storage device exterior material corresponds to the TD of the aluminum alloy foil.
• This sample is placed in a rectangular mold (female mold, surface is JIS B 0659-1: 2002 Annex 1 (reference)
• the maximum height roughness (nominal value of Rz) specified in Table 2 of the surface roughness standard piece for comparison is 3.2 ⁇ m.
• a molding die with a clearance of 0.3 mm from the mold (the surface of the male mold and the ridge line is specified in Table 2 of JIS B 0659-1: 2002 Annex 1 (reference) Comparative surface roughness standard piece,
• the maximum height roughness (nominal value of Rz) is 1.6 ⁇ m
• the surface other than the ridge line is specified in Table 2 of JIS B 0659-1: 2002 Annex 1 (reference) Comparative surface roughness standard piece
• the maximum height roughness (nominal value of Rz) is 3.2 ⁇ m.
• Examples 1A to 11A and Comparative Examples 1A to 4A since the thickness of each layer constituting the exterior material for an electric storage device is common, the evaluation criteria for the limit molding depth are unified, and the limit molding depth is 7. 0 mm or more was evaluated A, 6.0 mm or more and less than 7.0 mm was evaluated B, and less than 6.0 mm was evaluated C.
• the evaluation criteria for the limit molding depth are 6.0 mm or more. Evaluation B was made for 5.5 mm or more and less than 6.0 mm, and evaluation C was made for less than 5.5 mm. The results are shown in Tables 1A-3A.
• Evaluation criteria for peel strength are, for Examples 1A to 11A and Comparative Examples 1A to 4A, evaluation A for peel strength of 9.0 N / 15 mm or more, evaluation B for 7.0 N / 15 mm or more and less than 9.0 N / 15 mm, Less than 7.0 N/15 mm was evaluated as C.
• the peel strength was slightly reduced due to the inclusion of a pigment for coloring, so the evaluation criteria for peel strength were that the peel strength was 8.0 N / 15 mm.
• the above was evaluated A, 6.0 N/15 mm or more and less than 8.0 N/15 mm was evaluated B, and less than 6.0 N/15 mm was evaluated C. The results are shown in Tables 1A-3A.
• PET is a polyethylene terephthalate film
• ONy is an oriented nylon film
• DL is an adhesive layer in the base layer
• PPa is maleic anhydride-modified polypropylene
• PP is Polypropylene is shown
• the values in parentheses are the thickness ( ⁇ m).
• the numerical values in parentheses for Resin A and Resin B are compounding ratios (parts by mass).
• the exterior materials for electric storage devices of Examples 1A to 14A are composed of a laminate including, in order from the outside, at least a substrate layer, a barrier layer, and a heat-fusible resin layer.
• the two layers constitute a moldability-improving layer, and the moldability-improving layer consists of a resin A that is insoluble in ethyl acetate and a resin B that is soluble in ethyl acetate and has not reacted with the resin A.
• the moldability improving layer has a resin A content of 43% by mass or more and a resin B content of 4% by mass or more and 57% by mass or less.
• the exterior materials for power storage devices of Examples 1A to 3A and 6A to 14A are composed of a laminate including, in order from the outside, at least a substrate layer, a barrier layer, and a heat-fusible resin layer. At least one layer included in the laminate constitutes a formability improving layer having a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate.
• the exterior materials for electric storage devices of Examples 1A to 14A have excellent moldability.
• resins A-1 to A-2 and resins B-1 to B-5 used in Examples and Comparative Examples according to the third aspect are as follows. • Resin A-1: A two-liquid type polyurethane adhesive using a polyester polyol and an aromatic isocyanate compound. Resin A-2: A resin having a glass transition temperature higher than that of resin A-1, and is a two-liquid type polyurethane adhesive using a polyester polyol and an aromatic isocyanate compound. Resin B-1: A resin obtained by slightly mixing epoxy resin 1, which hardly reacts with resin A-1, with epoxy resin 2, which hardly reacts with resin A-1. Resin B-2: A resin different from the resin B-1 and having a structure similar to that of the epoxy resin 1, which hardly reacts with the resin A-1.
• Resin B-3 A resin different from the resins B-1 and B-2 and having a structure similar to that of the epoxy resin 2, which hardly reacts with the resin A-1.
• Resin B-4 A polycarbonate resin which is different from resins B-1, B-2 and B-3 and does not react with resin A-1.
• ⁇ Resin B-5 Resin B-1, Resin B-, which is different from Resin B-1, Resin B-2, Resin B-3 and Resin B-4 and does not substantially react with Resin A-1 2.
• the epoxy resin has the highest molecular weight at which the peak value of the differential molecular weight distribution curve is obtained.
• Examples 1B-4B and Comparative Examples 1B-2B An oriented polyethylene terephthalate (PET) film (12 ⁇ m thick) and an oriented nylon (ONy) film (15 ⁇ m thick) were prepared as base layers. Using a two-component urethane adhesive (polyol compound and aromatic isocyanate compound), the thickness of the adhesive layer (DL: formed by a dry lamination method) after curing is 3 ⁇ m, and the PET film and the ONy film are bonded. were adhered via an adhesive layer. Also, an aluminum foil (JIS H4160:1994 A8021H-O (thickness: 40 ⁇ m)) was prepared as a barrier layer.
• JIS H4160:1994 A8021H-O thickness: 40 ⁇ m
• each of the resin A-1 and the resins B-1 to B-5 described above has the composition (mass ratio) shown in Table 1B and the solid content excluding the solvent of the adhesive that forms the adhesive layer.
• An adhesive was prepared by mixing so that Next, using the obtained adhesive, an aluminum foil and a base layer (on the ONy film side) are laminated by a dry lamination method so that the adhesive layer has a thickness of 3 ⁇ m after curing, and then aging treatment is performed.
• a laminate of substrate layer/adhesive layer/barrier layer was produced by carrying out. Both sides of the aluminum foil are chemically treated.
• a treatment solution consisting of phenolic resin, fluorochromium compound, and phosphoric acid was applied to both sides of the aluminum foil by a roll coating method so that the coating amount of chromium was 10 mg/m 2 (dry mass). It was carried out by coating and baking.
• Example 5B and Comparative Example 3B The above-mentioned resin A-2 and resin B-1 are mixed and bonded so that the solid content excluding the solvent of the adhesive forming the adhesive layer has the composition (mass ratio) shown in Table 2B.
• An exterior material for an electric storage device was obtained in the same manner as in Example 1B-4B and Comparative Example 1B-2B, except that an adhesive layer was formed by preparing an agent.
• the laminate structure of the exterior material for an electricity storage device is as shown in Table 2B.
• a differential molecular weight distribution curve was obtained by obtaining the differential value of the curve at each molecular weight, and the molecular weight corresponding to the peak value on the vertical axis (dw/d (Log(M))) was obtained.
• the differential molecular weight distribution curve is a graph in which the horizontal axis indicates the molecular weight and the vertical axis indicates the value obtained by differentiating the concentration fraction by the logarithmic value of the molecular weight.
• the molecular weight at the position where the value obtained by differentiating the concentration fraction by the logarithmic value of the molecular weight is the highest is the molecular weight at which the peak value of the differential molecular weight distribution curve (see the position of P in FIG. 6).
• [Measurement condition] (Preprocessing) A measurement sample (resin B) is dissolved in a solvent (THF) to adjust the concentration to 1 W/V % (100 g/10 mL THF). Visually confirm that the sample is completely dissolved in the solvent. (measurement) The sample injection volume is 500 ⁇ L, the Flow is 4 mL/min, and the mobile phase is THF. The columns are Shodex K2001 (separation range: 100 to 2,500), K-2002 (separation range: 150 to 5,000), and K-2003 (separation range: 500 to 2 ⁇ 10 7 ). use.
• K-LG manufactured by Shodex
• the column temperature is normal temperature (25° C.).
• Adhesive is applied to a Si-coated PET film (release PET) to a thickness of about 90 ⁇ m to 100 ⁇ m, cured, and then peeled off from the release PET so that the total volume is 30 to 40 mm 3 .
• the mass (g) was measured with a scale capable of measuring to four decimal places (mass of the adhesive layer before immersion).
• a solvent ethyl acetate was placed in a screw bottle so that the adhesive single film whose mass had already been measured was immersed in the solvent, and stored in an environment of 25° C. for 12 hours or longer.
• the outer packaging material for an electricity storage device obtained above was cut to prepare a strip of 120 mm (TD) x 80 mm (MD), which was used as a test sample. Four test samples were prepared for each.
• the MD of the power storage device exterior material corresponds to the rolling direction (RD) of the aluminum alloy foil
• the TD of the power storage device exterior material corresponds to the TD of the aluminum alloy foil.
• the direction perpendicular to the same plane as MD and RD is TD.
• the rolling direction of the aluminum alloy foil can be confirmed by the rolling marks of the aluminum alloy foil.
• the mold is a 31.6 mm (MD) ⁇ 54.5 mm (TD) rectangular male mold (surface is JIS B 0659-1: 2002 Annex 1 (reference) Table 2 of surface roughness standard piece for comparison The maximum height roughness (nominal value of Rz) is 1.6 ⁇ m. Corner R 2.0 mm, ridge R 1.0 mm) and a female mold with a clearance of 0.3 mm from the 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 ⁇ m Corner R 2.0 mm , edge line R 1.0 mm).
• test sample was placed on the female mold so that the heat-sealable resin layer side was positioned on the male mold side. In each case, the test sample was pressed with a surface pressure of 0.37 MPa so that the molding depth was 5 mm so that no cracks or pinholes were opened during molding, and cold molding was performed in an environment of 25 ° C. molded). Next, the cold-molded sample was placed in a constant temperature/humidity chamber under an atmosphere of 80° C. and 90% RH, and allowed to stand still for 25 days. A molded sample is taken out from the constant temperature and humidity bath, and it is visually checked whether there is any floating (peeling of the base material layer) between the base material layer and the aluminum alloy foil.
• PET is a polyethylene terephthalate film
• ONy is an oriented nylon film
• DL is an adhesive layer in the base layer
• PPa is maleic anhydride-modified polypropylene
• PP is Polypropylene is shown, and the values in parentheses are the thickness ( ⁇ m).
• the exterior materials for electric storage devices of Examples 1B to 5B are composed of a laminate including at least a substrate layer, an adhesive layer, a barrier layer, and a heat-fusible resin layer in this order, and the adhesive layer is , the peak molecular weight of the differential molecular weight distribution curve measured using gel permeation chromatography is 35,000 or less.
• peeling between the base material layer and the barrier layer is preferably suppressed even when the molded power storage device exterior materials are placed in a high-temperature and high-humidity environment. ing.
• Section 1A Consists of a laminate comprising, in order from the outside, at least a substrate layer, a barrier layer, and a heat-fusible resin layer, At least one layer included in the laminate constitutes a moldability improving layer,
• the moldability improving layer contains a resin A that is insoluble in ethyl acetate and a resin B that is soluble in ethyl acetate and has not reacted with the resin A,
• the exterior material for an electricity storage device wherein the moldability improving layer has a content of the resin A of 43 mass % or more and a content of the resin B of 4 mass % or more and 57 mass % or less.
• Section 2A Section 2A.
• the exterior material for an electricity storage device wherein the resin A is at least one selected from the group consisting of urethane-based resins, polyamide-based resins, polyolefin-based resins, and polycarbonate-based resins.
• Section 3A The electricity storage device according to Item 1A or 2A, wherein the resin B is at least one selected from the group consisting of acrylic resins, epoxy resins, vinyl resins, polycarbonate resins, polystyrene resins, and silicone resins. exterior material. Section 4A.
• Consists of a laminate comprising, in order from the outside, at least a substrate layer, a barrier layer, and a heat-fusible resin layer, An exterior material for an electricity storage device, wherein at least one layer included in the laminate constitutes a formability improving layer having a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate.
• Section 5A. Item 4A, wherein the formability improving layer contains two or more resins.
• the moldability improving layer contains a resin A that is insoluble in ethyl acetate, Item 4A or 5A, wherein the moldability improving layer has a resin A content of 40% by mass or more.
• Item 7A The moldability improving layer contains a resin A that is insoluble in ethyl acetate, Item 4A or 5A, wherein the moldability improving layer has a resin A content of 40% by mass or more.
• the moldability improving layer contains a resin A that is insoluble in ethyl acetate and a resin B that is soluble in ethyl acetate and has not reacted with the resin A, Item 4A or 5A, wherein the moldability improving layer has a resin B content of 5% by mass or more and 60% by mass or less.
• Section 9A The moldability improving layer contains a resin A that is insoluble in ethyl acetate and a resin B that is soluble in ethyl acetate and has not reacted with the resin A, Item 4A or 5A, wherein the moldability improving layer has a resin B content of 5% by mass or more and 60% by mass or less.
• Item 8A The power storage device exterior material according to Item 8A, wherein the resin A is at least one selected from the group consisting of urethane-based resins, polyamide-based resins, polyolefin-based resins, and polycarbonate-based resins.
• the resin A is at least one selected from the group consisting of urethane-based resins, polyamide-based resins, polyolefin-based resins, and polycarbonate-based resins.
• Item 10A Item 8A or Item 9A, wherein the resin B is at least one selected from the group consisting of acrylic resins, epoxy resins, vinyl resins, polycarbonate resins, polystyrene resins, and silicone resins. exterior material.
• Item 11A The laminate includes a surface coating layer located on the opposite side of the base layer to the barrier layer, an adhesive layer located between the base layer and the barrier layer, the base layer and the barrier layer.
• a resin composition for use in an exterior material for an electricity storage device which is composed of a laminate comprising, in order from the outside, at least a substrate layer, a barrier layer, and a heat-fusible resin layer
• the resin composition contains a resin A that is insoluble in ethyl acetate and a resin B that is soluble in ethyl acetate and has not reacted with the resin A
• the resin composition is a resin composition in which the content of the resin A is 43 mass % or more and the content of the resin B is 4 mass % or more and 57 mass % or less. Item 14A.
• a resin composition for use in an exterior material for an electricity storage device which is composed of a laminate comprising, in order from the outside, at least a substrate layer, a barrier layer, and a heat-fusible resin layer,
• the resin composition has a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate. Item 15A.
• the moldability improving layer contains a resin A that is insoluble in ethyl acetate and a resin B that is soluble in ethyl acetate and has not reacted with the resin A,
• the method for producing an exterior material for an electricity storage device wherein the moldability improving layer has a content of the resin A of 43 mass % or more and a content of the resin B of 4 mass % or more and 57 mass % or less.
• a method for producing an exterior material for an electricity storage device wherein at least one layer included in the laminate constitutes a formability-improving layer having a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate.
• Item 17A An electricity storage device, wherein an electricity storage device element comprising at least a positive electrode, a negative electrode, and an electrolyte is housed in a package formed of the electricity storage device exterior material according to any one of Items 1A to 12A.
• Section 1B Consists of a laminate comprising at least a substrate layer, an adhesive layer, a barrier layer, and a heat-fusible resin layer in this order,
• the adhesive layer has a peak molecular weight of 35,000 or less in a differential molecular weight distribution curve measured using gel permeation chromatography.
• Section 2B. Item 1B, wherein the adhesive layer has a mass reduction rate of 6% or more and 50% or less when immersed in ethyl acetate.
• Section 3B Item 1B or 2B, wherein the adhesive layer contains two or more resins.
• the adhesive layer contains a resin A that is insoluble in ethyl acetate, The exterior material for an electricity storage device according to any one of Items 1B to 3B, wherein the adhesive layer has a content of the resin A of 40% by mass or more.
• the adhesive layer contains a resin A that is insoluble in ethyl acetate and a resin B that is soluble in ethyl acetate and is unreacted with the resin A, The exterior material for an electricity storage device according to any one of Items 1B to 4B, wherein the adhesive layer has a content of the resin B of 5% by mass or more and 60% by mass or less.
• the adhesive layer contains a resin A that is insoluble in ethyl acetate,
• the power storage device exterior material according to any one of Items 1B to 5B, wherein the resin A is at least one selected from the group consisting of urethane-based resins, polyamide-based resins, polyolefin-based resins, and polycarbonate-based resins. . Section 7B.
• the adhesive layer contains a resin A that is insoluble in ethyl acetate and a resin B that is soluble in ethyl acetate and is unreacted with the resin A, Any one of Items 1B to 6B, wherein the resin B is at least one selected from the group consisting of acrylic resins, epoxy resins, vinyl resins, polycarbonate resins, polystyrene resins, and silicone resins. 3.
• At least a step of laminating a substrate layer, an adhesive layer, a barrier layer, and a heat-fusible resin layer in this order to obtain a laminate The method for producing an exterior material for an electric storage device, wherein the adhesive layer has a molecular weight of 35,000 or less, which is a peak value of a differential molecular weight distribution curve measured using gel permeation chromatography.
• Item 9B An electricity storage device, wherein an electricity storage device element comprising at least a positive electrode, a negative electrode, and an electrolyte is housed in a package formed of the electricity storage device exterior material according to any one of Items 1B to 7B.

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