JP2011098759A - Packaging material for molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a packaging material for molding, having excellent forming property which is not subjected to pin holes or cracks even if the material is subjected to the deep-drawing forming, the stretch forming or the like with a large forming height. <P>SOLUTION: The packaging material 1 for forming includes a heat-resistant resin layer 2 as an outer layer, a thermoplastic resin layer 3 as an inner layer, and a metal foil layer 4 arranged between these layers. A biaxially stretched polypropylene film layer 5 is laminated and disposed between the thermoplastic resin layer 3 and the metal foil layer 4. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention is suitable, for example, as a packaging material suitably used as a case of a secondary battery such as a notebook computer, a mobile phone, an in-vehicle use, a stationary lithium ion secondary battery, or a packaging material for food or medicine. It relates to packaging materials.

  In order to prevent chemical changes, deterioration, decay, etc. of the contents of food, pharmaceuticals, etc. in the packaging material, laminate packaging materials using metal foils with excellent oxygen and moisture barrier properties have been widely used. ing.

  On the other hand, in recent years, with the reduction in size and weight of various electronic devices such as OA devices such as personal computers, mobile phones, game machines, headphone stereos, electronic notebooks, etc., the viewpoint of reducing the size and weight of the battery of the power supply unit Therefore, lithium ion polymer secondary batteries are often used. In this lithium ion polymer secondary battery, when the electrolytic solution in the battery reacts with water to generate hydrofluoric acid, the performance of the battery deteriorates, or liquid leakage occurs due to corrosion of the aluminum foil. As a material used for a case (accommodating case) of a lithium ion polymer secondary battery, a laminate packaging material having a high sealing property using a metal foil having an excellent water vapor barrier property has been used.

  Case materials (packaging materials) for lithium ion polymer secondary batteries include an outer layer made of a heat-resistant resin film, an intermediate layer made of aluminum foil as a water vapor barrier layer, and a polyolefin film for sealing the polymer electrolyte of the contents A laminated packaging material in which inner layers are sequentially laminated and integrated is used.

  In order to increase the capacity as much as possible to fill the polymer electrolyte, the laminate packaging material is molded into a three-dimensional rectangular parallelepiped shape by overhang molding or deep drawing to produce a battery case.

  However, since the aluminum foil is not spread like a synthetic resin film, when the laminate packaging material is formed into a rectangular parallelepiped shape or the like, pinholes are generated in the aluminum foil, or the aluminum foil is broken (broken). There was a problem that occurred. This is particularly noticeable when a sharp case with a deep molding height is obtained to increase the volume energy density.

  In order to solve the above problem, Patent Document 1 discloses a laminate comprising at least a base material layer, an adhesive layer, a chemical conversion treatment layer, aluminum, a chemical conversion treatment layer, an acid-modified polyolefin layer, and a polyolefin layer, and at least a base material. It has been proposed to use a packaging material for a lithium ion battery characterized in that the surface of the layer is coated with a fatty acid amide slip agent.

  Patent Document 2 discloses that a packaging material for forming a battery outer body in which a battery body is inserted and a peripheral portion is sealed by heat sealing includes at least a base material layer, an adhesive layer, aluminum, a chemical conversion treatment layer, an adhesive resin layer, A laminate comprising a polypropylene resin-based sealant layer, wherein the adhesive resin layer is made of acid-modified polypropylene having a melt index of 5 to 30 g / 10 minutes and a melt tension of 230 ° C. of 0.5 cN or more. It has been proposed to use a battery packaging material.

  Patent Document 3 discloses that a packaging material for forming a battery outer body in which a battery body is inserted and a peripheral portion is sealed by heat sealing includes at least a base material layer, an adhesive layer, a barrier layer, an adhesive resin layer, and a sealant layer. A layered structure in which at least the sealant layer is formed of a low-flowing polypropylene layer that is not easily crushed by heat and pressure by heat sealing, and a high-flowing polypropylene layer that is crushed easily. It has been proposed to use a battery packaging material characterized by this.

  Patent Document 4 discloses a lithium battery exterior material including at least a base material layer, an adhesive layer, an aluminum foil layer, an adhesive layer, an extruded resin layer, and a sealant layer, and the aluminum foil layer is at least on the adhesive layer side. The extruded resin layer is a polyethylene resin, the sealant layer is made of a co-extruded polypropylene resin having two or more layers, and the laminated surface side is a resin blended with homopolypropylene and polyethylene or a random copolymer. It has been proposed to use a lithium battery exterior material characterized in that it is made of a resin blended with polymerized polypropylene and the seal surface side is made of a resin blended with homopolypropylene or further with random copolymerized polypropylene.

JP 2002-216714 A JP 2003-31188 A JP 2003-7261 A JP 2006-134692 A

  However, in the technique described in Patent Document 1, it is necessary to provide a step of coating the surface of the outer layer film with an amide slip agent, and the productivity is lowered. In addition, the outer layer film and the aluminum foil are coated with the coated amide slip agent. There was a problem that sufficient laminate strength could not be obtained.

  In the techniques described in Patent Documents 2 to 4, only an unstretched polypropylene resin film is disposed on the inner layer side of the aluminum foil, or only a polypropylene and polyethylene blend resin film is disposed on the inner layer side of the aluminum foil. Therefore, when forming into a rectangular parallelepiped shape or the like, there is a problem that pinholes are generated in the aluminum foil or breakage portions (cracks) are easily generated in the aluminum foil, and sufficient moldability cannot be obtained. there were.

  As a result of intensive studies on the relationship between the above phenomenon and the packaging material structure, the present inventors arrange not only the outer layer side of the aluminum foil but also the inner layer side to provide a layer that can obtain a uniform elongation relative to the elongation during molding. Was found to be effective.

  The present invention has been made on the basis of such a novel technical idea (knowledge), and does not cause pinholes or cracks even when molding such as deep drawing or stretch molding with a deep molding height is performed. It aims at providing the packaging material for shaping | molding provided with the outstanding moldability.

  In order to achieve the above object, the present invention provides the following means.

[1] A molding packaging material comprising a heat-resistant resin layer as an outer layer, a thermoplastic resin layer as an inner layer, and a metal foil layer disposed between both layers,
A molding packaging material, wherein a biaxially stretched polypropylene film layer is laminated between the thermoplastic resin layer and the metal foil layer.

  [2] The molding packaging material according to item 1, wherein the thermoplastic resin layer is made of a copolymer resin having a melting point of 135 to 155 ° C. containing at least propylene and ethylene as a copolymer component.

  [3] The thermoplastic resin layer is composed of a laminate in which two or more thermoplastic resin layers are laminated, and at least the resin layer on the seal surface side (the innermost surface side) of the thermoplastic resin layer is a copolymer component. 2. The molding packaging material according to item 1, comprising a copolymer resin having a melting point of 135 to 155 ° C. containing at least propylene and ethylene.

  [4] Any one of the above items 1 to 3, wherein at least a surface of the biaxially oriented polypropylene film layer on the thermoplastic resin layer side is coated with a low melting point resin layer equal to or lower than the melting point of the thermoplastic resin layer. The molding packaging material according to claim 1.

  [5] The molding packaging material according to any one of items 1 to 4, wherein at least one surface of the metal foil layer is subjected to chemical conversion treatment.

  [6] The molding packaging material according to any one of items 1 to 5, which is used as a battery case.

  [7] The molding packaging material according to any one of items 1 to 5, which is used as a packaging material for food or medicine.

  In the invention of [1], since the biaxially stretched polypropylene film layer is laminated between the thermoplastic resin layer and the metal foil layer, even if molding such as deep drawing molding or stretch molding is performed on this packaging material. Pinholes and cracks do not occur, the moldability is excellent, and it is possible to mold with a sharp shape with a deep molding height. In addition, this biaxially stretched polypropylene film has excellent water vapor barrier properties, and its water vapor transmission rate is, for example, less than half of the water vapor transmission rate of unstretched polypropylene film. it can.

  In the invention of [2], the thermoplastic resin layer is composed of a copolymer resin having a melting point of 135 to 155 ° C. containing at least propylene and ethylene as a copolymerization component, so that sufficient heat resistance is ensured. It is possible to secure excellent sealing performance.

  In the invention of [3], the thermoplastic resin layer is composed of a laminate in which two or more thermoplastic resin layers are laminated, and at least the seal surface side (innermost inner surface side) resin layer of the thermoplastic resin layer is a common layer. Since it is the structure which consists of copolymer resin whose melting | fusing point which contains at least propylene and ethylene as a polymerization component and is 135-155 degreeC, it can ensure sufficient heat resistance and can ensure the outstanding sealing performance.

  In the invention of [4], at least the surface on the thermoplastic resin layer side in the biaxially stretched polypropylene film layer is coated with a low melting point resin layer equal to or lower than the melting point of the thermoplastic resin layer. When the plastic resin layer is extrusion laminated, it can be easily adhered, and the laminate strength between the biaxially stretched polypropylene film layer and the thermoplastic resin layer can be sufficiently secured.

  In the invention of [5], since the chemical conversion treatment is performed on at least one surface of the metal foil layer, corrosion of the surface of the metal foil by the contents (battery electrolyte, food, medicine, etc.) can be sufficiently prevented.

  According to the invention of [6], a battery case material excellent in moldability is provided.

  According to the invention of [7], a food packaging material excellent in moldability or a pharmaceutical packaging material excellent in moldability is provided.

It is sectional drawing which shows one Embodiment of the packaging material for shaping | molding concerning this invention. It is sectional drawing which shows other embodiment of the packaging material for shaping | molding concerning this invention. 6 is a cross-sectional view showing a molding packaging material of Comparative Example 1. FIG.

  One embodiment of a molding packaging material 1 according to the present invention is shown in FIG. The packaging material 1 for molding is formed into a rectangular parallelepiped shape or the like, for example, and used as a case of a lithium ion polymer secondary battery.

  The molding packaging material 1 includes a heat-resistant resin layer (outer layer) 2 laminated and integrated on the upper surface of the metal foil layer 4 via a first resin adhesive layer 11, and on the lower surface of the metal foil layer 4. A biaxially stretched polypropylene film layer 5 is laminated via a second resin adhesive layer 12, and a thermoplastic resin layer (inner layer) 3 is laminated and integrated on the lower surface of the biaxially stretched polypropylene film layer 5.

  Although it does not specifically limit as the said heat resistant resin layer (outer layer) 2, For example, a nylon film, a polyester film, etc. are mentioned, These stretched films are used preferably. Among these, as the heat resistant resin layer 2, a biaxially stretched nylon film, a biaxially stretched polybutylene terephthalate (PBT) film, a biaxially stretched polyethylene terephthalate (PET) film or a biaxially stretched polyethylene naphthalate (PEN) film is used. Is particularly preferred. The nylon film is not particularly limited, and examples thereof include 6 nylon film, 6,6 nylon film, MXD nylon film, and the like. In addition, the said heat resistant resin layer 2 may be formed by the single layer, or may be formed by the multilayer which consists of PET film / nylon film, for example.

  The thickness of the heat resistant resin layer 2 is preferably 12 to 50 μm. When a polyester film is used, the thickness is preferably 12 to 50 μm, and when a nylon film is used, the thickness is preferably 15 to 50 μm. By setting it above the preferred lower limit value, it is possible to ensure a sufficient strength as a packaging material, and by setting it below the preferred upper limit value, it is possible to reduce stress during stretch molding or draw molding, and to improve moldability.

  The metal foil layer 4 plays a role of providing the packaging material 1 with a gas barrier property that prevents oxygen and moisture from entering. Although it does not specifically limit as said metal foil layer 4, For example, aluminum foil, copper foil, etc. are mentioned, Aluminum foil is generally used. The thickness of the metal foil layer 4 is preferably 20 to 100 μm. When it is 20 μm or more, generation of pinholes during rolling when producing a metal foil can be prevented, and when it is 100 μm or less, stress during stretch forming or draw forming can be reduced and formability can be improved.

The metal foil layer 4 is preferably subjected to a chemical conversion treatment on at least one surface thereof, particularly on the surface of the thermoplastic resin layer side, and the contents (battery of the battery) are obtained by performing such chemical conversion treatment. Corrosion on the surface of the metal foil due to electrolyte, food, medicine, etc.) can be sufficiently prevented. For example, the metal foil 4 is subjected to chemical conversion treatment by performing the following treatment. That is, for example, on the surface of the metal foil 4 that has been degreased,
1) Aqueous solution comprising a mixture of phosphoric acid, chromic acid and fluoride metal salt 2) Aqueous solution comprising a mixture of phosphoric acid, chromic acid, fluoride metal salt and non-metal salt 3) Acrylic resin and / or phenolic resin Then, a chemical conversion treatment is performed by applying an aqueous solution composed of a mixture of phosphoric acid, chromic acid, and a fluoride metal salt.

The thermoplastic resin layer (inner layer) (sealant layer) 3 is not particularly limited, but an unstretched one is used. Specifically, for example, 1) propylene and ethylene are used as copolymerization components. Single-layer film layer comprising copolymer containing 2) Single-layer film layer comprising copolymer containing propylene, ethylene and butene as copolymer components 3) Block copolymer containing propylene and ethylene as copolymer components 4) A multilayer film layer 5 in which at least the resin layer on the seal surface side (content side) is made of a copolymer containing propylene and ethylene 5) at least on the seal surface side (content side) Multilayer film layer 6 in which the resin layer is composed of a copolymer containing propylene, ethylene and butene as copolymerization components) At least the sealing surface side (content side) Layer of the resin multilayer film layer and the like composed of a block copolymer containing propylene and ethylene as a copolymer component.

  The unstretched monolayer film of 1) to 3) may be blended with an olefin-based thermoplastic elastomer. Similarly, an olefinic thermoplastic elastomer may be blended with the resin layer on the sealing surface side in the unstretched multilayer films of 4) to 6).

  The resin layer at least on the sealing surface side (the innermost surface side) in the thermoplastic resin layer (inner layer) 3 has a peak temperature (melting point) measured at a heating rate of 20 ° C./min by DSC (differential scanning calorimeter). It is preferable to use one having a temperature of 135 to 155 ° C. When the melting point is 135 ° C. or higher, sufficient heat resistance can be secured, and when the melting point is 155 ° C. or lower, excellent sealing properties can be secured.

  The thickness of the thermoplastic resin layer 3 is preferably 10 to 80 μm. When it is 10 μm or more, sufficient seal strength can be obtained, and when it is 80 μm or less, it is sufficiently prevented that the water vapor barrier from the end face is damaged. The thermoplastic resin layer 3 may be composed of a single layer or a multilayer. By using multiple layers, for example, a resin layer with high fluidity is arranged on the outside (innermost layer side) of a resin layer with low fluidity, and the seal thickness becomes extremely thin due to abnormal flow of the thermoplastic resin layer during sealing. This can be sufficiently prevented.

  The biaxially stretched polypropylene film layer 5 needs to be stretched to such an extent that the yield point during the tensile test is substantially unclear. The film is preferably stretched 3 to 6 times in the flow direction (longitudinal direction) and 8 to 12 times in the direction perpendicular to the film flow direction. If the draw ratio is smaller than the lower limit of the above preferred range, the yield point during the tensile test appears, and there is a concern that uniform elongation may be hindered during molding. The stretching method is not particularly limited, and examples thereof include sequential biaxial stretching by a tenter method and simultaneous biaxial stretching by a tubular method.

  The biaxially stretched polypropylene film layer 5 is not particularly limited. For example, the biaxially stretched homopolypropylene film, the biaxially stretched propylene-ethylene copolymer resin film, or 10% by mass of homopolypropylene or ethylene. Examples thereof include a film obtained by biaxially stretching a resin layer in which an elastomer component composed of ethylene and polypropylene is added to random polypropylene copolymerized below by the above method.

  The thickness of the biaxially oriented polypropylene film layer 5 is preferably 15 to 80 μm. When the thickness is 15 μm or more, it can sufficiently prevent pinholes from being generated in the metal foil layer 4 or breakage of the metal foil layer 4 during molding such as deep drawing, and the thickness is 80 μm or less. In addition to being easy to seal, the stress at the time of stretch molding or drawing can be reduced, and the moldability can be improved.

  The biaxially stretched polypropylene film layer 5 may contain various additives such as an antioxidant, a slip agent, an antiblocking agent, an antistatic agent and a neutralizing agent as long as the effects of the present invention are not impaired. However, in the case where the biaxially stretched polypropylene film layer 5 and the metal foil 4 layer are laminated (laminated) with an adhesive, the biaxially stretched polypropylene film layer is used to prevent a decrease in laminate strength. It is preferable that no slip agent or antistatic agent is contained in No. 5, and it is particularly preferable that no antistatic agent is contained.

  At least the surface of the biaxially oriented polypropylene film layer 5 on the thermoplastic resin layer 3 side was coated with a low melting point resin layer (low melting point resin layer) 20 equal to or lower than the melting point of the thermoplastic resin layer 3. It is preferable to adopt the configuration (see FIG. 2). By providing this low melting point resin layer 20, the thermoplastic resin layer 3 can be easily adhered to the biaxially stretched polypropylene film layer 5 by extrusion lamination. The low melting point resin is not particularly limited, and a resin having a peak temperature (melting point) measured by DSC (differential scanning calorimeter) at a temperature rising rate of 20 ° C./min is 120 to 155 ° C. Is preferred. When the melting point is 120 ° C. or higher, sufficient heat resistance can be secured, and when the melting point is 155 ° C. or lower, the laminate strength with the thermoplastic resin layer can be sufficiently secured. Examples of the resin having a melting point of 120 to 155 ° C. include propylene-ethylene copolymers, ethylene-propylene elastomers, and blends thereof.

  Although it does not specifically limit as a method to manufacture the packaging material 1 for shaping | molding of this invention, If the example is given, the heat resistant resin stretched film (heat resistant) will be given to one side of the metal foil (metal foil layer) 4. Adhesive resin layer) 2 is bonded by a dry laminating method using an adhesive (first adhesive layer) 11, and then a biaxially stretched polypropylene film 5 is bonded to the other surface of the metal foil 4 with an adhesive (second adhesive). Layer) 12 is bonded by a dry laminating method, and an unstretched thermoplastic resin film (thermoplastic resin layer) 3 having a melting point of 135 to 155 ° C. measured by DSC is applied to the surface of the biaxially stretched polypropylene film 5. By bonding by an extrusion laminating method, the molding packaging material 1 of the present invention as shown in FIG. 1 is obtained.

  At this time, as the biaxially stretched polypropylene film 5, the surface (the surface to be bonded to the thermoplastic resin layer 3) is measured in advance by DSC (differential scanning calorimeter) at a heating rate of 20 ° C./min. It is preferable to use one having a structure in which a resin 20 having a peak temperature (melting point) of 120 to 155 ° C. (a resin having a melting point equivalent to that of the thermoplastic resin layer 3 or a low melting point resin having a lower melting point) 20 is bonded. In this case, the molding packaging material 1 having the configuration shown in FIG. 2 is obtained. The thickness of the low melting point resin layer 20 is preferably set to 5 to 10 μm.

  Although it does not specifically limit as an adhesive agent which comprises said 1st adhesive bond layer 11 and said 2nd adhesive bond layer 12, For example, the two-component curable urethane type which contains a polyol component and an isocyanate component An adhesive etc. are mentioned. This two-component curing type urethane-based adhesive is suitably used particularly when bonded by a dry laminating method. Although it does not specifically limit as said polyol component, For example, polyester polyol, polyether polyol, etc. are mentioned. The isocyanate component is not particularly limited, and examples thereof include diisocyanates such as TDI (tolylene diisocyanate), HDI (hexamethylene diisocyanate), and MDI (methylene bis (4,1-phenylene) diisocyanate). . The thickness of the first adhesive layer 11 and the thickness of the second adhesive layer 12 are both preferably set to 2 to 5 μm, particularly preferably 3 to 4 μm.

  Moreover, in the said embodiment, although the structure which provided the 1st adhesive bond layer 11 and the 2nd adhesive bond layer 12 is employ | adopted, these both adhesive bond layers 11 and 12 are not an essential structural layer, A configuration without these can also be employed. For example, if a heat laminating method (thermal laminating method) is used, the heat-resistant resin layer 2 and the metal foil layer 4 can be directly laminated and integrated. Similarly, a heat laminating method (thermal laminating method) is used. If used, the metal foil layer 4 and the biaxially stretched polypropylene layer 5 can be directly laminated and integrated.

  In the above embodiment, the biaxially stretched polypropylene layer 5 and the thermoplastic resin layer 3 are directly laminated and integrated. However, the present invention is not particularly limited to such a configuration. For example, the biaxially stretched polypropylene layer 5 And the thermoplastic resin layer 3 may be bonded by a dry laminating method using an adhesive.

  In addition, an inorganic or organic antiblocking agent or an amide slip agent may be added to the constituent resin as long as the effects of the present invention are not impaired.

  By forming the molding packaging material 1 of the present invention into various shapes such as a rectangular parallelepiped shape having a deep molding height (overhang molding, deep drawing molding, etc.), a battery case having a high volumetric energy density and a food packaging material Pharmaceutical packaging materials can be obtained. Battery cases, food packaging materials, and pharmaceutical packaging materials obtained by such molding have no pinholes or cracks, so they have excellent oxygen and moisture barrier properties and high reliability. .

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

<Example 1>
A chemical conversion treatment solution comprising polyacrylic acid, a trivalent chromium compound, water and alcohol is applied to both surfaces of an aluminum foil 4 having a thickness of 40 μm, and then dried at 180 ° C. for 5 seconds to give a chromium adhesion amount of 10 mg / m ^2. After that, a 25 μm thick biaxially stretched polyamide film (biaxially stretched nylon film) (heat resistant resin layer) 2 is dried on one surface of the aluminum foil 4 with a two-component curable urethane adhesive 11. Laminate, and then dry laminate the biaxially stretched polypropylene film 5 on the other surface of the aluminum foil 4 with a two-component curable urethane adhesive 12, and then have a melting point of 140 ° C. measured by DSC. A copolymer resin (thermoplastic resin layer) 3 is extruded on the surface of the biaxially oriented polypropylene film 5 with a thickness of 20 μm by extrusion lamination. By integrally laminated Ri, to obtain a molded packaging material 1 shown in FIG.

<Example 2>
A chemical conversion treatment solution comprising polyacrylic acid, a trivalent chromium compound, water and alcohol is applied to both surfaces of an aluminum foil 4 having a thickness of 40 μm, and then dried at 180 ° C. for 5 seconds to give a chromium adhesion amount of 10 mg / m ^2. After that, a 25 μm thick biaxially stretched polyamide film (biaxially stretched nylon film) (heat resistant resin layer) 2 is dried on one surface of the aluminum foil 4 with a two-component curable urethane adhesive 11. Lamination was performed to obtain a first laminate. Next, a propylene-ethylene-butene terpolymer resin (thermoplastic resin layer) 3 having a melting point of 135 ° C. measured by DSC is extruded on the surface of a 20 μm biaxially stretched polypropylene film 5 to a thickness of 20 μm. Lamination was performed to obtain a second laminate. The biaxially stretched polypropylene film 5 of the second laminate and the aluminum foil 4 of the first laminate are laminated and integrated with a two-component curable urethane adhesive 12 by a dry lamination method to obtain FIG. The molding packaging material 1 shown was obtained.

<Example 3>
A chemical conversion treatment solution comprising polyacrylic acid, a trivalent chromium compound, water and alcohol is applied to both surfaces of an aluminum foil 4 having a thickness of 40 μm, and then dried at 180 ° C. for 5 seconds to give a chromium adhesion amount of 10 mg / m ^2. After that, a 25 μm thick biaxially stretched polyamide film (biaxially stretched nylon film) (heat resistant resin layer) 2 is dried on one surface of the aluminum foil 4 with a two-component curable urethane adhesive 11. Laminate, and then dry laminate the biaxially stretched polypropylene film 5 on the other surface of the aluminum foil 4 with a two-component curable urethane adhesive 12, and then have a melting point of 155 ° C. measured by DSC. A copolymer resin (thermoplastic resin layer) 3 is extruded on the surface of the biaxially oriented polypropylene film 5 with a thickness of 20 μm by extrusion lamination. By integrally laminated Ri, to obtain a molded packaging material 1 shown in FIG.

<Example 4>
A chemical conversion treatment solution comprising polyacrylic acid, a trivalent chromium compound, water and alcohol is applied to both surfaces of an aluminum foil 4 having a thickness of 40 μm, and then dried at 180 ° C. for 5 seconds to give a chromium adhesion amount of 10 mg / m ^2. After that, a 25 μm thick biaxially stretched polyamide film (biaxially stretched nylon film) (heat resistant resin layer) 2 is dried on one surface of the aluminum foil 4 with a two-component curable urethane adhesive 11. Two layers of the biaxially stretched polypropylene film 5 laminated and then coated on the other surface of the aluminum foil 4 with a low melting point resin layer 20 made of a terpolymer of propylene-ethylene-butene having a melting point of 130 ° C. Propylene-ethylene random copolymer resin having a melting point of 140 ° C. measured by DSC after dry lamination with a curable urethane adhesive 12 ( The molding packaging material 1 shown in FIG. 2 was obtained by stacking and integrating the plastic resin layer 3 with a thickness of 20 μm on the surface of the low melting point resin layer 20 of the biaxially oriented polypropylene film 5 by extrusion lamination. .

<Comparative Example 1>
A biaxially stretched polyamide film (biaxially stretched nylon film) (heat resistant resin layer) 2 having a thickness of 25 μm is dry-laminated with a two-component curing urethane adhesive 11 on one surface of an aluminum foil 4 having a thickness of 40 μm. Then, a polypropylene film (thermoplastic resin layer) 3 having a melting point of 140 ° C. measured by DSC is dry-laminated with a two-component curable urethane adhesive 12 on the other surface of the aluminum foil 4 to obtain FIG. A packaging material for molding as shown in FIG.

  In addition, the said melting | fusing point is melting | fusing point measured with the temperature increase rate of 20 degree-C / min using the Shimadzu Corporation automatic differential scanning calorimeter (product number: DSC-60A).

  Each molding packaging material obtained as described above was evaluated for moldability and sealing performance based on the following evaluation method. The results are shown in Table 1.

<Formability evaluation method>
Using an overhang molding machine manufactured by Amada Co., Ltd. (product number: TP-25C-X2), overhang molding was performed in a rectangular parallelepiped shape of 55 mm in length, 35 mm in width, and 8 mm in depth, and formability was evaluated based on the following criteria.
(Criteria)
“○”… No pinholes and no cracks “△”… Slightly a few pinholes but virtually no “×”… Many pinholes on almost the entire surface Occurred.

<Seal performance evaluation method>
A seal peeling test was performed under conditions of 25 ° C. and 100 ° C. using Tensilon RTA-100 manufactured by Orientec Co., Ltd. and a constant temperature bath TCF-III1-B manufactured by Baldwin Co., Ltd., and the sealing performance was evaluated. The sealing conditions for each packaging material were 5 mm seal width, 0.3 MPa seal pressure, 1 second seal time, 160 ° C. and 180 ° C. double-sided heating.
(Seal performance criteria)
“◯”: A strength of 30 N / 15 mm was obtained in both cases of sealing at 160 ° C. and performing a seal peeling test at 25 ° C. and sealing at 180 ° C. and performing a seal peeling test at 100 ° C. × ”… Not applicable to the above (poor sealing performance).

  As is apparent from Table 1, the molding packaging materials of Examples 1 to 4 of the present invention were formed into a rectangular parallelepiped shape by performing the overhang molding under the above conditions, and no pinholes or cracks were generated. Excellent formability.

  On the other hand, in the molding packaging material of Comparative Example 1 in which the biaxially stretched polypropylene film layer is not provided between the thermoplastic resin layer and the metal foil layer, a number of pinholes are generated when molded into a rectangular parallelepiped shape by overhang molding. The moldability was poor.

  The molding packaging material according to the present invention is preferably used as a battery case for notebook computers, mobile phones, in-vehicle, stationary lithium ion polymer secondary batteries, etc. Although suitable as a packaging material for pharmaceuticals, it is not particularly limited to these uses.

1 ... Molding packaging material 2 ... Heat-resistant resin layer (outer layer)
3 ... Thermoplastic resin layer (inner layer)
4 ... Metal foil layer 5 ... Biaxially stretched polypropylene film layer 20 ... Low melting point resin layer

Claims (7)

A molding packaging material comprising a heat-resistant resin layer as an outer layer, a thermoplastic resin layer as an inner layer, and a metal foil layer disposed between both layers,
A molding packaging material, wherein a biaxially stretched polypropylene film layer is laminated between the thermoplastic resin layer and the metal foil layer.   The molding packaging material according to claim 1, wherein the thermoplastic resin layer is made of a copolymer resin having a melting point of 135 to 155 ° C. containing at least propylene and ethylene as a copolymer component.   The thermoplastic resin layer is composed of a laminate in which two or more thermoplastic resin layers are laminated, and at least the resin layer on the seal surface side of the thermoplastic resin layer contains at least propylene and ethylene as copolymerization components. The molding packaging material according to claim 1, comprising a copolymer resin having a melting point of 135 to 155 ° C.   The surface of at least the thermoplastic resin layer side in the biaxially oriented polypropylene film layer is coated with a low melting point resin layer equal to or lower than the melting point of the thermoplastic resin layer. The molding packaging material according to Item.   The molding packaging material according to any one of claims 1 to 4, wherein a chemical conversion treatment is applied to at least one surface of the metal foil layer.   The molding packaging material according to any one of claims 1 to 5, which is used as a battery case.   The molding packaging material according to any one of claims 1 to 5, which is used as a packaging material for foods or pharmaceuticals.

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