JP6640523B2 - Method for producing sealant film for exterior material of power storage device, exterior material for power storage device, power storage device, and resin composition for sealant film of exterior material for power storage device - Google Patents

Description

  The present invention relates to a sealant film used to constitute an exterior material of an electricity storage device, an exterior material for an electricity storage device using the sealant film, an electricity storage device constituted using the exterior material, and a resin for the sealant film. The present invention relates to a method for producing the composition.

  In this specification and claims, the term “melting point” means a melting peak temperature measured by differential scanning calorimetry (DSC) in accordance with JIS K7121-1987, and “crystal melting energy”. Means the heat of fusion (crystal melting energy) measured by differential scanning calorimetry (DSC) in accordance with JIS K7122-1987.

  In this specification and the claims, the term “crystal melting energy” refers to two or more crystal melting peak curves and two (△ Hm1, ΔHm2) or three crystal melting energies. If present, the highest value of the crystal melting energy is indicated.

  Further, in the present specification and claims, the term “polymer component” does not include any of “first elastomer-modified olefin-based resin” and “second elastomer-modified olefin-based resin”.

  Further, in the present specification and claims, “olefin-based elastomer” and “styrene-based elastomer” are defined, but an elastomer containing both olefin and styrene is classified into the above-mentioned “styrene-based elastomer” ( Classification) (belongs).

  In this specification and the appended claims, the term “aluminum” is used to include aluminum and its alloys.

  Lithium ion secondary batteries are widely used, for example, as power sources for notebook computers, video cameras, mobile phones, electric vehicles, and the like. As this lithium ion secondary battery, one having a configuration in which the periphery of a battery main body (a main body including a positive electrode, a negative electrode, and an electrolyte) is surrounded by a case is used. As the case material (exterior material), for example, a material in which an outer layer made of a heat-resistant resin film, an aluminum foil layer, and an inner layer made of a thermoplastic resin film are bonded and integrated in this order is known.

  The power storage device is configured such that the power storage device body is sandwiched between a pair of exterior materials, and the peripheral edges of the pair of exterior materials are sealed by fusion bonding (heat sealing).

  By the way, in a lithium ion secondary battery or the like, gas is easily generated in the battery body during overcharging or overheating, so that the gas gradually accumulates in the internal space covered with the exterior material, and The internal pressure inside may increase. Since there is a concern that the increase in the internal pressure may cause the exterior material to burst, a technique for preventing such exterior material bursting has been proposed.

  For example, Patent Literature 1 has an electrode laminate in which a sheet-shaped positive electrode and a negative electrode are laminated via a separator, and the electrode laminate is placed in a container made of a metal laminate film together with an electrolytic solution. An explosion-proof power storage device that is housed and hermetically sealed with a heat-sealing portion formed by heat-sealing the metal laminated film in a belt shape along the outer peripheral edge of the container, A blade support that is attached and fixed with the peripheral portion sandwiched therebetween, and a blade member that is supported by the blade support and that is disposed at a position closer to the center of the container than the heat-sealed portion. A hole punching device, wherein the blade support moves in the outer peripheral direction of the container by being pushed out by the container that expands and deforms when gas is generated, and the blade member moves together with the blade support. In explosion-proof function electric storage device has been made as to cut through the container is described.

  Patent Document 2 discloses a power storage element body impregnated with an electrolyte, an exterior body for sealing the energy storage element body, a first gas release mechanism provided inside the exterior body, and the exterior body. And a second gas release mechanism provided outside of the outer space, and gas from the internal space of the exterior body in which the power storage element body is present sequentially passes through each of the gas release mechanisms, so that gas from the internal space is removed from the internal space. A pressure adjusting device is provided that permits release of gas to the external space, and prevents gas from entering from the external space to the internal space at each of the gas release mechanisms, and between each of the gas release mechanisms. A power storage element in which a buffer space individually partitioned by each of the gas release mechanisms is formed is described.

JP 2012-156404 A JP 2012-156489 A

  However, when a drilling device having a blade support and a blade member is provided as in Patent Literature 1, a new process for providing the drilling device is required, which complicates the manufacturing process and increases productivity. There was a problem of lowering. In addition, since it is necessary to provide a new component called a drilling device, the cost increases accordingly.

  Further, when a safety valve mechanism (gas release mechanism or the like) for releasing gas generated inside the exterior body to the outside as in Patent Document 2, a new process for providing the safety valve mechanism is required. Therefore, there is a problem that the manufacturing process becomes complicated and the productivity is reduced. In addition, since a new component called a safety valve mechanism needs to be provided, the cost increases accordingly.

  As a solution to the above problems, the present applicant has a first resin layer containing at least 50% by mass of a random copolymer containing propylene and other copolymerization components other than propylene as a copolymerization component, and has a melting point of A first elastomer-modified olefin-based resin having a temperature of 155 ° C. or more and a crystal melting energy of 50 J / g or more, and a second elastomer-modified olefin-based resin having a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g or less And a second resin layer formed of a mixed resin containing: and a first resin-modified olefin-based resin, wherein the first elastomer-modified olefin-based resin is an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer. Wherein the second elastomer-modified olefin resin is an elastomer-modified homopolypropylene. Or / and an elastomer-modified random copolymer, wherein the elastomer-modified random copolymer is an elastomer-modified random copolymer containing propylene and other copolymer components other than propylene as copolymer components, In the second resin layer, a sealant film for an exterior material of a power storage device is proposed in which the total value of the content of the first elastomer-modified olefin-based resin and the content of the second elastomer-modified olefin-based resin is 50% by mass or more. (Japanese Patent Application No. 2015-190977). With such a configuration, the cost can be suppressed, sufficient sealing strength can be ensured, and when the internal pressure of the power storage device excessively increases, destruction occurs inside the sealant layer, gas is released, and the exterior pressure increases due to the increase in internal pressure. It has been found that the material can be prevented from being ruptured, and when the above-mentioned broken portion for preventing the rupture occurs, continuous breakage hardly proceeds from the broken portion as a starting point, and whitening during molding can be suppressed.

  As a result of further intensive studies, the present applicant has made it possible to sufficiently cause cohesive failure inside the sealant layer by setting the composition of the second resin layer of the sealant film having the above configuration to a specific composition. When a fracture (peeling) point occurs, it is possible to obtain an effect that continuous destruction from the fracture point is more difficult to progress, and it is also found that whitening during molding can be suppressed more sufficiently. The invention has been completed. Further, by producing the resin composition for the second resin layer by a specific method, it has been found that cohesive failure occurs more sufficiently inside the sealant layer, and the production method of the present invention has been completed. Things.

  The present invention has been made in view of such technical background, and has good productivity, can suppress costs, can secure sufficient sealing strength, and excessively increases the internal pressure of the power storage device. Occasionally, destruction (peeling) occurs inside the sealant layer and gas is released, so that the rupture of the exterior material due to an increase in internal pressure can be prevented. , A sealant film for an exterior material of an electricity storage device, an exterior material for an electricity storage device, a resin for an electricity storage device and a sealant film for an exterior material of an electricity storage device, which can hardly cause continuous destruction and can sufficiently suppress whitening during molding It is an object to provide a method for producing the composition.

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

[1] a first resin layer containing 50% by mass or more of a random copolymer containing propylene and another copolymerization component other than propylene as a copolymerization component,
Two or more layers including a first elastomer-modified olefin-based resin having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more, and a second resin layer formed of a composition including a polymer component. Consisting of a laminate of
The first elastomer-modified olefin-based resin is composed of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer,
The elastomer-modified random copolymer is an elastomer-modified random copolymer containing propylene and other copolymer components other than propylene as a copolymer component,
In the second resin layer, the content of the first elastomer-modified olefin-based resin is 50% by mass or more;
The polymer component is a random copolymer containing propylene and other copolymer components other than propylene as a copolymer component, homopolypropylene, at least one polymer component selected from the group consisting of olefin-based elastomers and styrene-based elastomers. A sealant film for an exterior material of an electricity storage device.

[2] a first resin layer containing 50% by mass or more of a random copolymer containing propylene and other copolymer components other than propylene as a copolymer component,
A first elastomer-modified olefin resin having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more, and a second elastomer-modified olefin resin having a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g or less A second resin layer formed of a composition containing a base resin and a polymer component, and a laminate of two or more layers containing:
The first elastomer-modified olefin-based resin is composed of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer,
The second elastomer-modified olefin-based resin is composed of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer,
The elastomer-modified random copolymer is an elastomer-modified random copolymer containing propylene and other copolymer components other than propylene as a copolymer component,
In the second resin layer, the total value of the content of the first elastomer-modified olefin-based resin and the content of the second elastomer-modified olefin-based resin is 50% by mass or more,
The polymer component is a random copolymer containing propylene and other copolymer components other than propylene as a copolymer component, homopolypropylene, at least one polymer component selected from the group consisting of olefin-based elastomers and styrene-based elastomers. A sealant film for an exterior material of an electricity storage device.

  [3] The sealant film for an exterior material of an electricity storage device according to the above item 2, wherein the content of the second elastomer-modified olefin-based resin in the second resin layer is 1% by mass to 50% by mass.

  [4] The sealant film for an exterior material of an electricity storage device according to the above item 2 or 3, wherein the second elastomer-modified olefin-based resin has two or more crystallization peaks in a DSC measurement graph.

  [5] The sealant film for an exterior material of an electricity storage device according to any one of items 1 to 4, wherein a content of the polymer component in the second resin layer is 1% by mass or more and less than 50% by mass.

[6] The elastomer in the elastomer-modified homopolypropylene is ethylene propylene rubber,
The sealant film for an exterior material of an electricity storage device according to any one of Items 1 to 5, wherein the elastomer in the elastomer-modified random copolymer is ethylene propylene rubber.

  [7] The exterior of the electricity storage device according to any one of Items 1 to 6, wherein the first resin layer further contains an antiblocking agent and a slip agent, and the second resin layer further contains a slip agent. Sealant film for materials.

  [8] The sealant film for an exterior material of an electricity storage device according to any one of the above items 1 to 7, comprising only the first resin layer and a second resin layer laminated on one surface of the first resin layer.

  [9] Including the second resin layer, a first resin layer laminated on one surface of the second resin layer, and a first resin layer laminated on the other surface of the second resin layer 8. The sealant film for an exterior material of a power storage device according to any one of the above items 1 to 7, which is a laminate in which at least three layers are laminated.

[10] Including a base material layer as an outer layer, an inner sealant layer made of the sealant film according to any one of the above items 1 to 9, and a metal foil layer arranged between these two layers,
The exterior material for a power storage device, wherein the first resin layer is disposed on an innermost layer side in the inner sealant layer.

  [11] An exterior case for an electricity storage device, comprising a molded article of the exterior material for an electricity storage device according to the above item 10.

  [12] A method for manufacturing an outer case for an electricity storage device, comprising deep-drawing or bulging the exterior material for an electricity storage device according to item 10 above.

[13] a power storage device body,
An exterior member comprising the exterior material for an electricity storage device according to the preceding clause 10 and / or the exterior case for an electricity storage device according to the preceding clause 11,
The power storage device, wherein the power storage device main body is exteriorly covered with the exterior member.

[14] a pre-melt kneading step of melt-kneading one or more elastomer components and one or more plastomer components to obtain a first melt-kneaded product;
The first melt-kneaded product, a first elastomer-modified olefin resin having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more, and a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g. Mixing the following second elastomer-modified olefin-based resin with a resin composition to obtain a resin composition.

  [15] The elastomer component used in the preliminary melt-kneading step is an olefin-based elastomer, a styrene-based elastomer, and a second elastomer-modified olefin-based resin having a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g or less. 15. The method for producing a resin composition for a sealant film of an exterior material for an electric storage device according to the item 14, which is one or more elastomer components selected from the group consisting of:

  [16] The plastomer component used in the preliminary melt-kneading step is made of random polypropylene, homopolypropylene, and a first elastomer-modified olefin resin having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more. 16. The method for producing a resin composition for a sealant film of an exterior material for an electric storage device according to the above 14 or 15, which is one or more plastomer components selected from the group.

[17] The elastomer component used in the preliminary melt-kneading step is a second elastomer-modified olefin resin having a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g or less,
The plastomer component used in the preliminary melt-kneading step contains a first elastomer-modified olefin-based resin having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more, and further comprises random polypropylene or / and homopolypropylene. 15. The method for producing a resin composition for a sealant film of an exterior material for an electric storage device according to the above item 14, which comprises the composition.

[18] a pre-melt kneading step of melt-kneading one or more elastomer components and one or more plastomer components to obtain a first melt-kneaded product;
A step of mixing the first melt-kneaded product with a first elastomer-modified olefin-based resin having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more to obtain a resin composition. A method for producing a resin composition for a sealant film of an exterior material for an electric storage device, comprising the steps of:

  [19] The elastomer component used in the preliminary melt-kneading step is an olefin-based elastomer, a styrene-based elastomer, and a second elastomer-modified olefin-based resin having a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g or less. 19. The method for producing a resin composition for a sealant film of an exterior material for an electric storage device according to the above item 18, which is one or more elastomer components selected from the group consisting of:

  [20] The plastomer component used in the preliminary melt-kneading step is made of random polypropylene, homopolypropylene, and a first elastomer-modified olefin-based resin having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more. 20. The method for producing a resin composition for a sealant film of an exterior material for an electric storage device according to the above item 18 or 19, wherein the resin composition is one or more plastomer components selected from the group.

  [21] The sealant for an exterior material of a power storage device according to any one of the above items 14 to 20, wherein the mixing mass ratio of the elastomer component / plastomer component is set in the range of 5/95 to 70/30 in the preliminary melt-kneading step. A method for producing a resin composition for a film.

  In the invention [1], since the first resin layer containing 50% by mass or more of the random copolymer containing “propylene” and “other copolymerization components other than propylene” as the copolymerization component is provided, By arranging the first resin layer on the innermost layer side of the inner sealant layer in the exterior material, sufficient sealing can be achieved even at a relatively low temperature (sufficient sealing strength can be ensured). In addition, since the second resin layer contains the first elastomer-modified olefin resin having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more, the compatibility between the elastomer phase and the olefin resin phase is improved. Good, the dispersibility of the elastomer phase is also good, so that when the inner pressure is excessively increased for a pair of exterior materials in which the inner sealant layers are heat-seal-bonded to each other, when the seal portion is broken, In the second resin layer, cohesive failure occurs (inside the sealant layer), and destruction (peeling) hardly occurs at the interface between the metal foil layer and the inner sealant layer. This has the advantage that continuous destruction starting from the destruction point is unlikely to occur.

  In addition, since the compatibility of the interface between the elastomer phase and the olefin-based resin phase is good, voids (cavities generated inside the molded product) are hardly generated, and whitening during molding is suppressed. In addition, since the melting point of the first elastomer-modified olefin-based resin is 155 ° C. or more, the second resin layer is not easily crushed during heat sealing, and sufficient insulation can be secured.

  Further, since the second resin layer contains the specific polymer component together with the first elastomer-modified olefin resin having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more, the internal pressure is excessively increased. By doing so, when the seal portion breaks, cohesive failure occurs sufficiently in the second resin layer (inside the sealant layer), and when the breakage (peeling) portion for preventing rupture occurs, The effect that continuous breakage from the breakage point as a starting point is more difficult to obtain can be obtained, and whitening during molding can be suppressed more sufficiently.

  Furthermore, since it is not necessary to separately provide a new component (a drilling device or a gas release mechanism as in the prior art) in order to allow the gas to escape to the outside, the cost can be reduced and the size can be further reduced. And the productivity is good.

  In the invention of [2], since the first resin layer containing 50% by mass or more of the random copolymer containing “propylene” and “other copolymerization components other than propylene” as the copolymerization component is provided, By arranging the first resin layer on the innermost layer side of the inner sealant layer in the exterior material, sufficient sealing can be achieved even at a relatively low temperature (sufficient sealing strength can be ensured). The second resin layer has a melting point of 155 ° C. or more and a first elastomer-modified olefin resin having a crystal melting energy of 50 J / g or more, and a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g. Since the composition is a combination of the following second elastomer-modified olefin-based resin, the compatibility between the elastomer phase and the olefin-based resin phase is good, and the dispersibility of the elastomer phase is also good. When the seal part breaks due to an excessive increase in internal pressure of a pair of exterior materials in which the inner sealant layers are heat-sealed to each other, cohesive failure occurs in the second resin layer (in the sealant layer). Since the destruction (peeling) hardly occurs at the interface between the metal foil layer and the inner sealant layer, the destruction (peeling) portion for preventing the rupture occurred. There is an advantage that hardly proceeds destruction continuous as a starting point the breaking point to.

  In addition, since the compatibility of the interface between the elastomer phase and the olefin-based resin phase is good, voids (cavities generated inside the molded product) are hardly generated, and whitening during molding is suppressed. In addition, since the melting point of the first elastomer-modified olefin-based resin is 155 ° C. or more, the second resin layer is not easily crushed during heat sealing, and sufficient insulation can be secured.

  In addition, since the second resin layer further contains the specific polymer component, when the seal portion breaks due to an excessive increase in internal pressure, cohesive failure occurs in the second resin layer (in the sealant layer). Is sufficiently generated, and when the breakage (peeling) portion for preventing rupture is generated, an effect that continuous breakage from the broken portion as a starting point is more difficult to progress is obtained, and whitening during molding is obtained. Can be suppressed more sufficiently.

  Furthermore, since it is not necessary to separately provide a new component (a drilling device or a gas release mechanism as in the prior art) in order to allow the gas to escape to the outside, the cost can be reduced and the size can be further reduced. And the productivity is good.

  According to the invention as recited in the aforementioned Item [3], the above effects can be sufficiently ensured. In particular, the second resin layer is harder to be crushed at the time of heat sealing, and further sufficient insulation can be secured.

  According to the invention as recited in the aforementioned Item [4], the above effects can be more sufficiently ensured.

  According to the invention as recited in the aforementioned Item [5], the above effects can be more sufficiently ensured.

  In the invention as recited in the aforementioned Item [6], the above effects can be more sufficiently ensured.

  According to the invention as recited in the aforementioned Item [7], excellent sliding properties can be imparted to the surface of the exterior material, and when molding the exterior material, the molding with a deeper molding depth can be performed satisfactorily, and the whitening during molding is sufficient. Can be suppressed.

  In the inventions of [8] and [9], the above effects can be more sufficiently ensured.

  According to the invention as recited in the aforementioned Item [10], the productivity is good, the cost can be suppressed, a sufficient sealing strength can be ensured. In addition, when the internal pressure of the electricity storage device excessively increases, the second resin layer (the inside of the sealant layer) In this case, cohesive failure occurs, so that degassing can be performed to prevent rupture of the exterior material due to an increase in internal pressure, and, when the above-described rupture location for rupture prevention occurs, continuous destruction starting from the rupture location This makes it possible to provide an exterior material for an electricity storage device, which hardly progresses and can suppress whitening during molding.

  According to the invention as recited in the aforementioned Item [11], the productivity is good, the cost can be suppressed, sufficient sealing strength can be ensured, and when the internal pressure of the power storage device excessively increases, the second resin layer (the inside of the sealant layer) In this case, cohesive failure occurs, so that degassing can be performed to prevent rupture of the exterior material due to an increase in internal pressure, and, when the above-described rupture location for rupture prevention occurs, continuous destruction starting from the rupture location It is possible to provide an outer case for an electricity storage device, which is difficult to progress and can suppress whitening during molding.

  According to the invention as recited in the aforementioned Item [12], cost can be suppressed, sufficient sealing strength can be ensured, and when the internal pressure of the power storage device rises excessively, cohesive failure occurs in the second resin layer (in the sealant layer). Therefore, it is possible to prevent the rupture of the exterior material due to an increase in internal pressure due to degassing, and it is difficult for continuous destruction to proceed from the rupture location when the rupture location for preventing rupture occurs, and to form An outer case for a power storage device that can suppress whitening at the time can be manufactured with high production efficiency.

  According to the invention as recited in the aforementioned Item [13], sufficient sealing strength can be ensured for the exterior material, and when the internal pressure of the power storage device excessively increases, cohesive failure occurs in the second resin layer (in the sealant layer), and gas is released. In addition, it is possible to prevent the exterior material from being ruptured due to an increase in internal pressure, and it is difficult for continuous destruction to proceed from the rupture location when the rupture location for preventing rupture occurs, and also to suppress whitening during molding. And a power storage device that can be provided.

  In the invention [14], in the preliminary melt-kneading step, the first melt-kneaded product is obtained by melt-kneading the elastomer component and the plastomer component. In the first melt-kneaded product, the elastomer component and the plastomer component mutually interact. Since the first melt-kneaded material is mixed with a specific first elastomer-modified olefin-based resin (plastomer phase) and a specific second elastomer-modified olefin-based resin (elastomer phase) because it is mixed with high dispersibility. By doing so, the obtained resin composition has extremely excellent compatibility at the interface between the elastomer phase and the plastomer phase (non-elastomer phase). Therefore, the exterior material for an electricity storage device configured using the sealant film including the second resin layer formed of the obtained resin composition is a pair of exterior materials in which the inner sealant layers are heat-sealed to each other. When the seal portion is broken due to an excessive increase in the internal pressure, cohesive failure occurs sufficiently in the second resin layer (inside the sealant layer) and breaks at the interface between the metal foil layer and the inner sealant layer ( Since peeling is extremely unlikely to occur, when a break (peeling) location for preventing rupture occurs, continuous breakage starting from the broken location is extremely unlikely to occur, and whitening during molding is also achieved. More sufficiently can be suppressed.

  According to the invention as recited in the aforementioned Item [15], a resin composition having excellent compatibility at the interface between the elastomer phase and the plastomer phase (non-elastomer phase) can be obtained.

  According to the invention as recited in the aforementioned Item [16], a resin composition having more excellent compatibility at the interface between the elastomer phase and the plastomer phase (non-elastomer phase) can be obtained.

  According to the invention as recited in the aforementioned Item [17], a resin composition having more excellent compatibility at the interface between the elastomer phase and the plastomer phase (non-elastomer phase) can be obtained.

  In the invention [18], in the preliminary melt-kneading step, the elastomer component and the plastomer component are melt-kneaded to obtain a first melt-kneaded product. In the first melt-kneaded product, the elastomer component and the plastomer component mutually interact. Since the first melt-kneaded product and a specific first elastomer-modified olefin resin (plastomer phase) are mixed with each other with a high dispersibility, the resulting resin composition becomes an elastomer phase and a plastomer phase. The compatibility of the interface of the phase (non-elastomeric phase) is very good. Therefore, the exterior material for an electricity storage device configured using the sealant film including the second resin layer formed of the obtained resin composition is a pair of exterior materials in which the inner sealant layers are heat-sealed to each other. When the seal portion is broken due to an excessive increase in the internal pressure, cohesive failure occurs sufficiently in the second resin layer (inside the sealant layer) and breaks at the interface between the metal foil layer and the inner sealant layer ( Since peeling is extremely unlikely to occur, when a break (peeling) location for preventing rupture occurs, continuous breakage starting from the broken location is extremely unlikely to occur, and whitening during molding is also achieved. More sufficiently can be suppressed.

  According to the invention as recited in the aforementioned Item [19], a resin composition having excellent compatibility at the interface between the elastomer phase and the plastomer phase (non-elastomer phase) can be obtained.

  According to the invention as recited in the aforementioned Item [20], it is possible to obtain a resin composition having more excellent compatibility at the interface between the elastomer phase and the plastomer phase (non-elastomer phase).

  According to the invention as recited in the aforementioned Item [21], a resin composition having more excellent compatibility at the interface between the elastomer phase and the plastomer phase (non-elastomer phase) can be obtained.

It is sectional drawing which shows one Embodiment of the exterior | packing material for electric storage devices which concerns on this invention. It is sectional drawing which shows other embodiment of the exterior | packing material for electric storage devices which concerns on this invention. 1 is a cross-sectional view illustrating an embodiment of a power storage device according to the present invention. FIG. 4 is a perspective view showing an exterior material (planar one), an electricity storage device main body, and an exterior case (three-dimensional molded body) constituting the electricity storage device of FIG. 3 in a separated state before heat sealing.

  FIG. 1 shows an embodiment of the exterior material 1 for a power storage device according to the present invention. The exterior material 1 for an electric storage device is used, for example, as an exterior material for a lithium ion secondary battery. The power storage device exterior material 1 may be used as it is as it is without being molded, or may be used as the exterior case 10 by being subjected to molding such as deep drawing or bulging. Good (see FIG. 4).

  In the exterior material 1 for an electric storage device, a base layer (outer layer) 2 is laminated and integrated on one surface of a metal foil layer 4 via a first adhesive layer 5, and the other side of the metal foil layer 4. The inner sealant layer (inner layer) 3 is laminated and integrated on the surface of the second adhesive layer 6 via the second adhesive layer 6 (see FIGS. 1 and 2).

  In the exterior material 1 of FIG. 1, the inner sealant layer (inner layer) 3 has a configuration including only a first resin layer 7 and a second resin layer 8 laminated on one surface of the first resin layer. One resin layer 7 is disposed on the innermost layer side.

  2, the inner sealant layer (inner layer) 3 includes a second resin layer 8, a first resin layer 7 laminated on one surface of the second resin layer 8, The first resin layer 7 has a three-layer structure including the first resin layer 7 laminated on the other surface of the second resin layer 8, and one of the first resin layers 7 is disposed on the innermost layer side.

  The detailed configuration of the first resin layer 7 and the second resin layer 8 will be described later.

  In the present invention, the inner sealant layer (inner layer) 3 has excellent chemical resistance to a highly corrosive electrolytic solution or the like used in a lithium ion secondary battery or the like, and is heat-sealed to the exterior material. It plays a role of giving the property.

  In the present invention, the inner sealant layer (inner layer) 3 is composed of a laminate of two or more layers including a first resin layer 7 and a second resin layer 8. The first resin layer 7 contains at least 50% by mass of a random copolymer containing “propylene” and “other copolymer components other than propylene” as copolymer components.

The second resin layer 8 is formed of any one of the following compositions a) and b).
a) A composition comprising a first elastomer-modified olefin-based resin having a melting point (Tmp) of 155 ° C. or more and a crystal melting energy (ΔHm) of 50 J / g or more, and a specific polymer component.
b) a first elastomer-modified olefin resin having a melting point (Tmp) of 155 ° C. or more and a crystal melting energy (ΔHm) of 50 J / g or more, and a melting point (Tmp) of 135 ° C. or more and a crystal melting energy A composition comprising a second elastomer-modified olefin resin having a (ΔHm) of 30 J / g or less and a specific polymer component.

As the specific polymer component,
A random copolymer containing “propylene” and “other copolymer components other than propylene” as copolymer components,
・ Homo polypropylene,
・ Olefin elastomers, and
-Use at least one polymer component selected from the group consisting of styrene elastomers. The “other copolymer component other than propylene” in the random copolymer is not particularly limited, but, for example, ethylene, 1-butene, 1-hexene, 1-pentene, 4-methyl-1- In addition to olefin components such as pentene, butadiene and the like can be mentioned. Examples of the olefin-based elastomer include ethylene propylene rubber (EPR), ethylene butene rubber (EBR), ethylene-propylene-diene rubber (EPDM), isoprene rubber (IR), butadiene rubber (BR), and butyl rubber (IIR). Is mentioned. Examples of the styrene elastomer include styrene-ethylene-butylene-styrene copolymer (SEBS) and styrene-butadiene rubber (SBR).

  In the present invention, since the second resin layer 8 contains the specific polymer component in any of the configurations a) and b), the second resin layer 8 does not contain the specific polymer component (Reference Example 1). As compared with the above-described 3), when the seal portion is broken due to an excessive increase in the internal pressure of the pair of exterior materials in which the inner sealant layers are heat-sealed to each other, the sealant layer is formed by the second resin layer 8. (Inside) cohesive failure occurs sufficiently (as is clear from the comparison between Reference Examples 1 to 3 and Examples 1 to 29), and whitening during molding can be more sufficiently suppressed (Reference Examples 1 to 3). 3 and Examples 1-29).

  The innermost layer of the inner sealant layer (inner layer) 3 is preferably formed of the first resin layer 7 (see FIGS. 1 and 2).

  The first elastomer-modified olefin-based resin (first polypropylene block copolymer) is preferably composed of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer. It is an elastomer modified product of a random copolymer containing `` propylene '' and `` other copolymer components other than propylene '', and the `` other copolymer components other than propylene '' are not particularly limited, For example, in addition to olefin components such as ethylene, 1-butene, 1-hexene, 1-pentene, and 4-methyl-1-pentene, butadiene and the like can be mentioned. The elastomer is not particularly limited, but EPR (ethylene propylene rubber) is preferably used.

  The second elastomer-modified olefin-based resin (second polypropylene block copolymer) is preferably composed of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer, and the elastomer-modified random copolymer is a copolymer component having a content of “ It is an elastomer modified product of a random copolymer containing `` propylene '' and `` other copolymer components other than propylene '', and the `` other copolymer components other than propylene '' are not particularly limited, For example, in addition to olefin components such as ethylene, 1-butene, 1-hexene, 1-pentene, and 4-methyl-1-pentene, butadiene and the like can be mentioned. The elastomer is not particularly limited, but EPR (ethylene propylene rubber) is preferably used.

  The first resin layer 7 is configured to contain at least 50% by mass of a random copolymer containing “propylene” and “other copolymer components other than propylene” as copolymer components. Examples of the “other copolymer components other than propylene” are not particularly limited, and include, for example, olefin components such as ethylene, 1-butene, 1-hexene, 1-pentene, and 4-methyl-1-pentene. Other examples include butadiene. When the content of the random copolymer is 50% by mass or more, sufficient heat sealing strength can be secured. Above all, the content of the random copolymer in the first resin layer 7 is preferably set to 70% by mass or more. The random copolymer (a random copolymer containing propylene and other copolymer components other than propylene as a copolymer component) is preferably a random copolymer having a melting point of 2 or more. In this case, The heat-sealing performance can be further improved (heat-sealing strength can be further increased) by the low-melting-point random copolymer component, and the high-melting-point random copolymer component can be used at the time of heat sealing. The effect that one resin layer 7 is hard to be crushed and more sufficient insulation can be secured can be obtained.

  When the second resin layer 8 is formed of any one of the compositions a) and b), if the melting point of the first elastomer-modified olefin resin is less than 155 ° C., whitening occurs to some extent during molding, At the time of heat sealing, the second resin layer 8 is easily crushed, and the insulating property is likely to be insufficient (see Comparative Example 3). If the first elastomer-modified olefin-based resin has a crystal melting energy (ΔHm) of less than 50 J / g, the cohesion at the peeling interface is moderate, and the cohesive failure at the peeling interface hardly occurs. Peeling is likely to occur at the interface between the inner sealant layer and the inner sealant layer, continuous peeling is likely to proceed from the peeling point at this interface, and the second resin layer 8 is likely to be crushed, resulting in insufficient insulation (Comparative Example) 5).

  In the case where the second resin layer 8 is formed of the composition b), if the melting point of the second elastomer-modified olefin resin is less than 135 ° C., whitening occurs to some extent during molding (see Comparative Example 4). When the crystal melting energy (ΔHm) of the second elastomer-modified olefin resin exceeds 30 J / g, whitening occurs to some extent during molding (see Comparative Example 6).

  If the second resin layer 8 does not contain a first elastomer-modified olefin resin having a melting point (Tmp) of 155 ° C. or more and a crystal melting energy (エ ネ ル ギ ー Hm) of 50 J / g or more, In addition to the occurrence of whitening to some extent, the degree of cohesion at the peeling interface is medium, and the cohesive failure of the peeling interface is not easily caused. That is, peeling is likely to occur at the interface between the metal foil layer and the inner sealant layer at the time of peeling. From the starting point, the second resin layer 8 tends to be crushed, and the insulating property tends to be insufficient (see Comparative Example 2).

  The melting point of the first elastomer-modified olefin resin is preferably 155 ° C. or more and 185 ° C. or less. The crystal melting energy of the first elastomer-modified olefin-based resin is preferably 50 J / g or more and 75 J / g or less, more preferably 53 J / g or more and 70 J / g or less. The melting point of the second elastomer-modified olefin-based resin is preferably from 135 ° C. to 175 ° C. The crystal melting energy of the second elastomer-modified olefin resin is preferably 5 J / g or more and 30 J / g or less, more preferably 10 J / g or more and 25 J / g or less, and more preferably 10 J / g or more and 20 J / g. g is particularly preferred.

  Regarding the first elastomer-modified olefin-based resin and the second elastomer-modified olefin-based resin, the mode of “elastomer-modified” may be graft polymerization or other modified modes.

  The first elastomer-modified olefin-based resin and the second elastomer-modified olefin-based resin can be produced, for example, by the following reactor-made method. This is merely an example, and is not particularly limited to one manufactured by such a manufacturing method.

  First, a Ziegler-Natta catalyst, a co-catalyst, propylene and hydrogen are supplied to the first reactor to polymerize homopolypropylene. The obtained homopolypropylene is transferred to the second reactor while containing unreacted propylene and the Ziegler-Natta catalyst. In the second reactor, propylene and hydrogen are further added to polymerize homopolypropylene. The obtained homopolypropylene is transferred to the third reactor while containing unreacted propylene and the Ziegler-Natta catalyst. In the third reactor, ethylene, propylene and hydrogen are further added to polymerize ethylene-propylene rubber (EPR) obtained by copolymerizing ethylene and propylene, whereby the first elastomer-modified olefin-based resin or the second elastomer-modified olefin-based resin is added. Resin can be manufactured. For example, the first elastomer-modified olefin-based resin can be produced by adding a solvent and producing in a liquid phase, or the second elastomer-modified olefin-based resin can be produced by reacting in a gas phase without using a solvent. Can be manufactured.

  In the second resin layer 8, the content of the first elastomer-modified olefin-based resin is preferably 99% by mass to 50% by mass, more preferably 95% by mass to 70% by mass, and more preferably 90% by mass. % To 75% by mass.

  In the second resin layer 8, the content of the polymer component is preferably 1% by mass or more and less than 50% by mass, more preferably 5% by mass or more and 45% by mass or less, and more preferably 10% by mass or more and 30% by mass or less. It is particularly preferred that the content be not more than mass%.

  When the second resin-modified layer 8 contains the second elastomer-modified olefin-based resin, the content of the second elastomer-modified olefin-based resin in the second resin layer 8 is 1% by mass to 50% by mass. Is preferable, and especially 5 mass%-30 mass% is more preferred, and it is especially preferred that it is 10 mass%-25 mass%.

  The second resin layer 8 is preferably in the form of a sea-island structure. With such a sea-island structure, when the seal portion breaks due to an excessive increase in internal pressure, breakage occurs at the interface between the olefin-based resin phase and the elastomer phase in the second resin layer 8. As a result, cohesive failure occurs inside the second resin layer 8, so that breakage (peeling) hardly occurs at the interface between the metal foil layer and the inner sealant layer. In this case, the effect that continuous destruction starting from the destruction point is unlikely to proceed is sufficiently obtained. In the sea-island structure, a mode in which the elastomer (component) forms an island is preferable.

  It is preferable that the second elastomer-modified olefin-based resin has two or more crystallization peaks in a DSC (differential scanning calorimeter) measurement graph. In the case of having two crystallization peaks, the crystallization peak (crystallization temperature) on the high temperature side is 90 ° C. or more, and the crystallization peak (crystallization temperature) on the low temperature side is 80 ° C. or less. Is preferred. In the case of having three or more crystallization peaks, the highest temperature crystallization peak (crystallization temperature) is 90 ° C. or more, and the lowest temperature crystallization peak (crystallization temperature) is 80 ° C. It is preferred that:

  It is preferable that the first resin layer 7 has a configuration not having a sea-island structure. In such a case, the power storage device main body 31 is housed in the exterior material 1 and / or the external case 10 and heat-sealing of the peripheral portions (including the flange portion 29) is performed to encapsulate the power storage device main body 31. Later, when the peripheral portion (including the flange portion 29) is bent, it is possible to sufficiently suppress the formation of voids (spaces) at the interface between the olefin resin phase and the elastomer phase in the first resin layer 7. There is an advantage that sufficient insulation can be ensured. In particular, in the case where the first resin layer 7 is arranged at a position adjacent to the metal foil layer 7 (see FIG. 2), the above-mentioned effect becomes remarkable.

  The first resin layer 7 preferably contains an anti-blocking agent and a slip agent together with the random copolymer. Further, the second resin layer 8 contains a slip agent in addition to the first elastomer-modified olefin-based resin or in addition to the first elastomer-modified olefin-based resin and the second elastomer-modified olefin-based resin. Is preferred.

  The anti-blocking agent is not particularly limited, and examples thereof include silica and aluminum silicate. The slip agent is not particularly limited, and examples thereof include fatty acid amides such as erucic acid amide, stearic acid amide, and oleic acid amide, and waxes such as crystallin wax and polyethylene wax.

  The sealant film forming the inner sealant layer (inner layer) 3 is preferably manufactured by a molding method such as multilayer extrusion molding, inflation molding, or T-die cast film molding.

  The thickness of the inner sealant layer (inner layer) 3 is preferably set to 20 μm to 80 μm. When the thickness is 20 μm or more, the occurrence of pinholes can be sufficiently prevented, and when the thickness is 80 μm or less, the amount of resin used can be reduced and cost can be reduced. Above all, the thickness of the inner sealant layer (inner layer) 3 is particularly preferably set to 30 μm to 50 μm.

  The inner sealant layer (inner layer) 3 has a second resin layer 8, a first resin layer 7 laminated on one surface of the second resin layer 8, and a second resin layer 8 on the other surface of the second resin layer 8. In the case of a three-layer structure (see FIG. 2) composed of the first resin layer 7 and the first resin layer 7, the thickness ratio of the first resin layer 7 / second resin layer 8 / first resin layer 7 is: It is preferably in the range of 0.5 / 9 / 0.5 to 3/4/3.

  The method of laminating the sealant film constituting the inner sealant layer (inner layer) 3 on the metal foil layer 4 is not particularly limited, but may be a dry laminating method, a sandwich laminating method (an adhesive film such as an acid-modified polypropylene). Extruded, and sand-laminated between the metal foil and the sealant film, and then heat-laminated with a hot roll).

  In the present invention, the base layer (outer layer) 2 is preferably formed of a heat-resistant resin layer. As the heat-resistant resin constituting the heat-resistant resin layer 2, a heat-resistant resin that does not melt at a heat sealing temperature at the time of heat-sealing the exterior material is used. As the heat-resistant resin, it is preferable to use a heat-resistant resin having a melting point higher than the melting point of the thermoplastic resin constituting the inner sealant layer 3 by 10 ° C. or more, and a heat-resistant resin having a melting point higher than the melting point of the thermoplastic resin by 20 ° C. or more. It is particularly preferable to use a conductive resin.

  The heat-resistant resin layer (outer layer) 2 is not particularly limited, but includes, for example, a polyamide film such as a nylon film, a polyester film and the like, and these stretched films are preferably used. Above all, as the heat-resistant resin layer 2, a biaxially stretched polyamide film such as a biaxially stretched nylon film, a biaxially stretched polybutylene terephthalate (PBT) film, a biaxially stretched polyethylene terephthalate (PET) film, or a biaxially stretched polyethylene film It is particularly preferable to use a phthalate (PEN) film. The nylon film is not particularly limited, and examples thereof include a 6 nylon film, a 6,6 nylon film, and an MXD nylon film. The heat-resistant resin layer 2 may be formed as a single layer, or may be formed as, for example, a polyester film / polyamide film multilayer (a PET film / nylon film multilayer). Is also good.

  The thickness of the base layer (outer layer) 2 is preferably 2 μm to 50 μm. When a polyester film is used, the thickness is preferably 2 μm to 50 μm, and when a nylon film is used, the thickness is preferably 7 μm to 50 μm. By setting the preferred upper limit or more, sufficient strength as an exterior material can be secured, and by setting the preferred upper limit or less, stress during molding such as bulging and drawing can be reduced, and formability is improved. Can be done.

  In the present invention, the metal foil layer 4 has a role of providing the exterior material 1 with a gas barrier property for preventing intrusion of oxygen and moisture. The metal foil layer 4 is not particularly limited, but includes, for example, aluminum foil, SUS foil (stainless steel foil), copper foil, and the like. Among them, aluminum foil and SUS foil (stainless steel foil) are used. Is preferred. The thickness of the metal foil layer 4 is preferably 20 μm to 100 μm. When the thickness is 20 μm or more, pinholes can be prevented from being generated at the time of rolling when manufacturing a metal foil, and when the thickness is 100 μm or less, the stress at the time of forming such as bulging and drawing can be reduced, thereby improving the formability. be able to.

The metal foil layer 4 is preferably subjected to a chemical conversion treatment on at least the inner surface (the surface on the side of the second adhesive layer 6). By performing such a chemical conversion treatment, it is possible to sufficiently prevent corrosion of the surface of the metal foil due to contents (such as an electrolyte solution of a battery). For example, a chemical conversion treatment is applied to the metal foil by performing the following treatment. That is, for example, on the surface of the metal foil subjected to the degreasing treatment,
1) phosphoric acid,
Chromic acid,
An aqueous solution of a mixture containing at least one compound selected from the group consisting of a metal salt of fluoride and a nonmetal salt of fluoride; 2) phosphoric acid;
Acrylic resin, at least one resin selected from the group consisting of chitosan derivative resin and phenolic resin,
An aqueous solution of a mixture containing at least one compound selected from the group consisting of chromic acid and a chromium (III) salt; 3) phosphoric acid;
Acrylic resin, at least one resin selected from the group consisting of chitosan derivative resin and phenolic resin,
At least one compound selected from the group consisting of chromic acid and chromium (III) salts,
An aqueous solution of a mixture containing at least one compound selected from the group consisting of a metal salt of fluoride and a non-metallic salt of fluoride, after applying an aqueous solution of any of the above 1) to 3), followed by drying Thus, a chemical conversion treatment is performed.

The conversion coating, chromium coating weight preferably is 0.1mg / m ² ~50mg / m ² as a (per one surface), in particular 2mg / m ² ~20mg / m 2 preferred.

  The first adhesive layer 5 is not particularly limited, and examples thereof include a polyurethane adhesive layer, a polyester polyurethane adhesive layer, and a polyether polyurethane adhesive layer. It is preferable that the thickness of the first adhesive layer 5 is set to 1 μm to 5 μm. In particular, the thickness of the first adhesive layer 5 is particularly preferably set to 1 μm to 3 μm from the viewpoint of reducing the thickness of the exterior material 1 and reducing the weight.

  The second adhesive layer 6 is not particularly limited. For example, those exemplified as the first adhesive layer 5 can be used. However, a polyolefin-based adhesive which is less swelled by an electrolytic solution is used. Is preferred. The thickness of the second adhesive layer 6 is preferably set to 1 μm to 5 μm. In particular, the thickness of the second adhesive layer 6 is particularly preferably set to 1 μm to 3 μm from the viewpoint of reducing the thickness of the exterior material 1 and reducing the weight.

  The exterior case 1 (battery case etc.) 10 can be obtained by molding (deep-drawing molding, overhang molding, etc.) the exterior material 1 of the present invention (FIG. 4). The exterior material 1 of the present invention can be used as it is without being used for molding (FIG. 4).

  FIG. 3 shows an embodiment of the electric storage device 30 configured using the exterior material 1 of the present invention. This power storage device 30 is a lithium ion secondary battery. In the present embodiment, as shown in FIGS. 3 and 4, the exterior member 15 is configured by the exterior case 10 obtained by molding the exterior material 1 and the planar exterior material 1. Thus, a substantially rectangular parallelepiped power storage device main body (such as an electrochemical element) 31 is housed in the housing recess of the outer case 10 obtained by molding the outer material 1 of the present invention. And the outer sealant 1 of the present invention is disposed with the inner sealant layer 3 side inward (lower side) without being formed, and the periphery of the inner sealant layer 3 of the planar outer sealant 1 is The power storage device 30 of the present invention is configured by sealing and sealing the inner caseant layer 3 of the flange portion (peripheral portion for sealing) 29 of the outer case 10 by heat sealing (FIG. 3). , 4). The inner surface of the housing recess of the outer case 10 is an inner sealant layer 3, and the outer surface of the housing recess is a base material layer (outer layer) 2 (see FIG. 4).

  In FIG. 3, reference numeral 39 denotes a heat seal portion in which a peripheral portion of the exterior material 1 and a flange portion (a peripheral portion for sealing) 29 of the external case 10 are joined (welded). In the power storage device 30, the tip of the tab lead connected to the power storage device body 31 is led out of the exterior member 15, but is not shown.

  The power storage device main body 31 is not particularly limited, and examples thereof include a battery main body, a capacitor main body, and a capacitor main body.

  The width of the heat seal portion 39 is preferably set to 0.5 mm or more. When the thickness is 0.5 mm or more, the sealing can be reliably performed. In particular, the width of the heat seal portion 39 is preferably set to 3 mm to 15 mm.

  In the above-described embodiment, the exterior member 15 has the configuration including the exterior case 10 obtained by molding the exterior material 1 and the planar exterior material 1 (see FIGS. 3 and 4). It is not particularly limited to such a combination. For example, the exterior member 15 may be configured to include a pair of planar exterior members 1 or may be configured to include a pair of exterior cases 10. You may.

  Next, a preferred example of a method for producing a resin composition for a sealant film (resin composition for a second resin layer) of a power storage device exterior material will be described below.

  In the first production method, one or more elastomer components and one or more plastomer components are melt-kneaded to obtain a first melt-kneaded product (preliminary melt-kneading step).

  Next, the first melt-kneaded product obtained in the preliminary melt-kneading step is mixed with a first elastomer-modified olefin-based resin having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more. A resin composition (may be mixed by melt kneading or the like in addition to ordinary mixing) is obtained. In the first production method, the first elastomer-modified olefin-based resin is preferably made of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer, and the elastomer-modified random copolymer is used as a copolymer component. It is a modified elastomer of a random copolymer containing propylene and another copolymer component other than propylene (the detailed structure of the first elastomer-modified olefin resin is as described above).

  In the second production method, one or more kinds of elastomer components and one or more kinds of plastomer components are melt-kneaded to obtain a first melt-kneaded product (preliminary melt-kneading step).

  Next, a first melt-kneaded product obtained in the preliminary melt-kneading step, a first elastomer-modified olefin-based resin having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more, and a melting point of 135 ° C. And a second elastomer-modified olefin-based resin having a crystal melting energy of 30 J / g or less, to obtain a resin composition (may be mixed by melt kneading or the like in addition to ordinary mixing). In the second production method, the first elastomer-modified olefin-based resin is preferably composed of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer, and the second elastomer-modified olefin-based resin is preferably an elastomer-modified homoolefin. The elastomer-modified random copolymer is preferably made of polypropylene or / and an elastomer-modified random copolymer, and the elastomer-modified random copolymer is an elastomer-modified random copolymer containing propylene and other copolymer components other than propylene as a copolymer component. (The more detailed configuration of the first and second elastomer-modified olefin-based resins is as described above).

  In the first and second production methods, the elastomer component used in the preliminary melt-kneading step is an olefin-based elastomer, a styrene-based elastomer, and a material having a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g or less. It is preferably one or more elastomer components selected from the group consisting of certain second elastomer-modified olefin resins. The second elastomer-modified olefin-based resin that can be used in the preliminary melt-kneading step is preferably made of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer, and the elastomer-modified random copolymer is preferably It is an elastomer modified product of a random copolymer containing propylene and other copolymer components other than propylene as a copolymer component (a more detailed configuration of the second elastomer-modified olefin resin is as described above). Examples of the olefin-based elastomer include ethylene propylene rubber (EPR), ethylene butene rubber (EBR), ethylene-propylene-diene rubber (EPDM), isoprene rubber (IR), butadiene rubber (BR), and butyl rubber (IIR). Is mentioned. Examples of the styrene elastomer include styrene-ethylene-butylene-styrene copolymer (SEBS) and styrene-butadiene rubber (SBR).

  In the first and second production methods, the plastomer component used in the preliminary melting and kneading step is a random polypropylene, a homopolypropylene, and a plastomer component having a melting point of 155 ° C. or more and a crystal melting energy of 50 J / g or more. One or more plastomer components selected from the group consisting of one elastomer-modified olefin-based resin are preferred. The first elastomer-modified olefin-based resin that can be used in the preliminary melt-kneading step is preferably made of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer. It is a modified elastomer of a random copolymer containing propylene as a copolymerization component and another copolymerization component other than propylene (a more detailed configuration of the first elastomer-modified olefin resin is as described above). The random polypropylene that can be used in the preliminary melt-kneading step is a random copolymer containing “propylene” and “other copolymer components other than propylene” as copolymer components, and the above-mentioned “excluding propylene”. Examples of the other copolymer component include, but are not particularly limited to, olefin components such as ethylene, 1-butene, 1-hexene, 1-pentene, and 4-methyl-1-pentene, butadiene, and the like. No.

  In the preliminary melting and kneading step, the mixing mass ratio of the elastomer component / plastomer component is preferably set in the range of 5/95 to 70/30.

  In the first production method, it is preferable that the mixing mass ratio of the first melt-kneaded product / the first elastomer-modified olefin-based resin is set in a range of 5/95 to 40/60.

  Further, in the second production method, 95 parts by mass to 50 parts by mass of the first elastomer-modified olefin-based resin and 5 parts by mass of the second elastomer-modified olefin-based resin with respect to 100 parts by mass of the first melt-kneaded material. Parts to 50 parts by mass are preferably mixed.

  In the above-described manufacturing method, the method may be used when manufacturing the above-mentioned “sealant film for an exterior material of an electricity storage device” (a laminate of two or more layers including the first resin layer 7 and the second resin layer 8) of the present invention. Cut parts that are not to be produced, such as ears and off-gauge parts, can be used as a kneading material in the pre-melt kneading step, for example, obtained by granulating a crushed product obtained by crushing in a semi-molten state. .

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

<Reference Example 1>
A chemical conversion solution consisting of phosphoric acid, polyacrylic acid (acrylic resin), a chromium (III) salt compound, water and alcohol was applied to both sides of a 35 μm-thick aluminum foil 4 and dried at 180 ° C. Then, a chemical conversion film was formed. The amount of chromium adhering to this conversion coating was 10 mg / m ² per one side.

  Next, a biaxially-stretched 6-nylon film 2 having a thickness of 15 μm was dry-laminated (laminated) to one surface of the chemically treated aluminum foil 4 via a two-component curable urethane-based adhesive 5.

  Next, a 4 μm thick first resin layer 7 made of an ethylene-propylene random copolymer and a 22 μm thick second resin layer 8 (a first resin layer having a melting point of 163 ° C. and a crystal melting energy of 58 J / g) were used. A second resin layer 8) composed of 99% by mass of an elastomer-modified olefin-based resin, 1% by mass of a second elastomer-modified olefin-based resin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g, ethylene-propylene random A 30 μm thick sealant film formed by laminating these three layers by co-extrusion using a T-die so that three first resin layers 7 each having a thickness of 4 μm made of a copolymer are laminated in this order. After obtaining (first resin layer / second resin layer / first resin layer) 3, one surface of the first resin layer 7 of the sealant film 3 is coated with a two-part curable maleic acid-modified polypropylene. Laminated on the other surface of the dry-laminated aluminum foil 4 via an adhesive 6 and sandwiched between a rubber nip roll and a laminating roll heated to 100 ° C. and pressed to perform dry lamination. Thereafter, aging (heating) was performed at 50 ° C. for 5 days to obtain an exterior material for a power storage device having the configuration shown in FIG.

In addition, as the two-component curable maleic acid-modified polypropylene adhesive, 100 parts by mass of maleic acid-modified polypropylene (melting point: 80 ° C., acid value: 10 mg KOH / g) as a main component, and isocyanurate of hexamethylene diisocyanate as a curing agent (NCO content: 20% by mass) 8 parts by mass of an adhesive solution further mixed with a solvent was used, and the adhesive solution was coated on the aluminum foil 4 such that the solid content was 2 g / m ² . After applying to the other surface and drying by heating, it was superimposed on one of the first resin layers 7 of the sealant film 3.

<Reference Example 2>
As the second resin layer 8, a second resin layer having a thickness of 22 μm (90% by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, a melting point of 136 ° C., 2 in the same manner as in Reference Example 1 except that a second elastomer-modified olefin-based resin having a crystal melting energy of 18 J / g and a composition of 10% by mass was used. The exterior material was obtained.

<Reference Example 3>
As the second resin layer 8, a second resin layer having a thickness of 22 μm (80% by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, a melting point of 144 ° C., 2 in the same manner as in Reference Example 1 except that a second elastomer-modified olefin-based resin having a composition of 20% by mass having a crystal melting energy of 19 J / g was used. The exterior material was obtained.

<Example 1>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 3.5 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 3.5 parts by mass of a modified olefin resin and 1 part by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) were melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 8 parts by mass of the first melt-kneaded material, 85.5 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 136 ° C. And 9.5 parts by mass of a second elastomer-modified olefin-based resin having a crystal melting energy of 18 J / g to obtain a resin composition. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 2>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 7 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 1 part by mass of the base resin and 2 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) were melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 10 parts by mass of the first melt-kneaded material, 72 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 18 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 3>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 2 parts by mass of the base resin and 4 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) were melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 4>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 21 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 3 parts by mass of a system resin and 6 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) were melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, a resin composition is prepared by mixing 30 parts by mass of the first melt-kneaded material with 70 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g. I got Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 5>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 35 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 5 parts by mass of a base resin and 10 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) were mixed and kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, a resin composition is prepared by mixing 50 parts by mass of the first melt-kneaded material with 50 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g. I got Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 6>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 21 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 3 parts by mass of a base resin, 3 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) and 3 parts by mass of homopolypropylene were mixed and melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. . Next, 30 parts by mass of the first melt-kneaded material, 56 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 14 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 7>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 8 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 2 parts by mass of the base resin were mixed and melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 10 parts by mass of the first melt-kneaded material, 72 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 18 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 8>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 2 parts by mass of a base resin, 2 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.), and 2 parts by mass of ethylene propylene rubber are mixed and kneaded at 210 ° C. to obtain a first melt-kneaded product. Was. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 9>
As the resin composition constituting the second resin layer 8, a resin composition obtained as follows is used, and as the resin composition constituting the first resin layer 7, an ethylene-propylene random copolymer (Tmp; Except that 145 ° C.) was used, the exterior material 1 for an electricity storage device having the configuration shown in FIG. 2 was obtained in the same manner as in Reference Example 1. First, 16 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) and 4 parts by mass of ethylene propylene rubber (EPR) were mixed and kneaded at 210 ° C. to obtain a first melt-kneaded product. . Next, 20 parts by mass of the first melt-kneaded material, 56 parts by mass of a first elastomer-modified olefin resin having a melting point of 166 ° C. and a crystal melting energy of 65 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing with 24 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. The second resin layer 8 was formed using this resin composition.

<Example 10>
As the resin composition constituting the second resin layer 8, a resin composition obtained as follows is used, and as the resin composition constituting the first resin layer 7, an ethylene-propylene random copolymer (Tmp; Except that 145 ° C.) was used, the exterior material 1 for an electricity storage device having the configuration shown in FIG. 2 was obtained in the same manner as in Reference Example 1. First, 14 parts by mass of homopolypropylene and 4 parts by mass of ethylene butylene rubber (EBR) were mixed and melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 20 parts by mass of the first melt-kneaded material, 56 parts by mass of a first elastomer-modified olefin resin having a melting point of 166 ° C. and a crystal melting energy of 65 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 24 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. The second resin layer 8 was formed using this resin composition.

<Example 11>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 6 parts by mass of the base resin were mixed and melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 12>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g and 6 parts by mass of ethylene propylene rubber (EPR) are mixed and melt-kneaded at 210 ° C. One melt-kneaded product was obtained. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 13>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and 6 parts by mass of a styrene-ethylene-butylene-styrene copolymer (SEBS) were mixed and mixed. The first melt-kneaded product was obtained by melt-kneading at ℃. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 14>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.), 6 parts by mass of a second elastomer-modified olefin resin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g were mixed. Then, the mixture was melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 15>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) and 6 parts by mass of ethylene butylene rubber (EBR) were mixed and melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. . Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 16>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) and 6 parts by mass of a styrene-ethylene-butylene-styrene copolymer (SEBS) are mixed and melt-kneaded at 210 ° C. One melt-kneaded product was obtained. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 17>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of a homopolypropylene, 6 parts by mass of a second elastomer-modified olefin resin having a melting point of 136 ° C. and a crystal melting energy of 18 J / g were mixed and kneaded at 210 ° C. to obtain a first melt-kneaded product. I got Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 18>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of homopolypropylene and 6 parts by mass of ethylene propylene rubber (EPR) were mixed and melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 19>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of homopolypropylene and 6 parts by mass of styrene-ethylene-butylene-styrene copolymer (SEBS) were mixed and melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 20>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 6 parts by mass of the base resin were mixed and melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, a resin composition is prepared by mixing 20 parts by mass of the first melt-kneaded material with 80 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g. I got Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 21>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g and 6 parts by mass of ethylene propylene rubber (EPR) are mixed and melt-kneaded at 210 ° C. One melt-kneaded product was obtained. Next, a resin composition is prepared by mixing 20 parts by mass of the first melt-kneaded material with 80 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g. I got Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 22>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and 6 parts by mass of a styrene-ethylene-butylene-styrene copolymer (SEBS) were mixed and mixed. The first melt-kneaded product was obtained by melt-kneading at ℃. Next, a resin composition is prepared by mixing 20 parts by mass of the first melt-kneaded material with 80 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g. I got Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 23>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.), 6 parts by mass of a second elastomer-modified olefin resin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g were mixed. Then, the mixture was melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, a resin composition is prepared by mixing 20 parts by mass of the first melt-kneaded material with 80 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g. I got Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 24>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) and 6 parts by mass of ethylene butylene rubber (EBR) were mixed and melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. . Next, a resin composition is prepared by mixing 20 parts by mass of the first melt-kneaded material with 80 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g. I got Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 25>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) and 6 parts by mass of a styrene-ethylene-butylene-styrene copolymer (SEBS) are mixed and melt-kneaded at 210 ° C. One melt-kneaded product was obtained. Next, a resin composition is prepared by mixing 20 parts by mass of the first melt-kneaded material with 80 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g. I got Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 26>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of a homopolypropylene, 6 parts by mass of a second elastomer-modified olefin resin having a melting point of 136 ° C. and a crystal melting energy of 18 J / g were mixed and kneaded at 210 ° C. to obtain a first melt-kneaded product. I got Next, a resin composition is prepared by mixing 20 parts by mass of the first melt-kneaded material with 80 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g. I got Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 27>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of homopolypropylene and 6 parts by mass of ethylene propylene rubber (EPR) were mixed and melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, a resin composition is prepared by mixing 20 parts by mass of the first melt-kneaded material with 80 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g. I got Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Example 28>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, in the same manner as in Reference Example 1, the exterior material 1 for the electricity storage device having the configuration shown in FIG. I got First, 14 parts by mass of homopolypropylene and 6 parts by mass of styrene-ethylene-butylene-styrene copolymer (SEBS) were mixed and melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, a resin composition is prepared by mixing 20 parts by mass of the first melt-kneaded material with 80 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g. I got Except that the second resin layer 8 was formed using this resin composition, the exterior material 1 for an electric storage device was obtained in the same manner as in Reference Example 1.

<Comparative Example 1>
Except for using a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g instead of the ethylene-propylene random copolymer as the resin constituting the first resin layer 7, In the same manner as in Example 3, a packaging material for a power storage device was obtained.

<Comparative Example 2>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, the exterior material for the electricity storage device having the configuration shown in FIG. Obtained. First, 14 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 2 parts by mass of the base resin and 4 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) were melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, a resin composition is prepared by mixing 20 parts by mass of the first melt-kneaded material with 80 parts by mass of a second elastomer-modified olefin-based resin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. I got A packaging material for a power storage device was obtained in the same manner as in Example 3, except that the second resin layer 8 was formed using this resin composition.

<Comparative Example 3>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, the exterior material for the electricity storage device having the configuration shown in FIG. Obtained. First, 14 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 2 parts by mass of the base resin and 4 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) were melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 145 ° C. and a crystal melting energy of 57 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. A packaging material for a power storage device was obtained in the same manner as in Example 3, except that the second resin layer 8 was formed using this resin composition.

<Comparative Example 4>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, the exterior material for the electricity storage device having the configuration shown in FIG. Obtained. First, 14 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 2 parts by mass of the base resin and 4 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) were melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin-based resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 130 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 14 J / g. A packaging material for a power storage device was obtained in the same manner as in Example 3, except that the second resin layer 8 was formed using this resin composition.

<Comparative Example 5>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, the exterior material for the electricity storage device having the configuration shown in FIG. Obtained. First, 14 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 2 parts by mass of the base resin and 4 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) were melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 155 ° C. and a crystal melting energy of 49 J / g, and a melting point of 144 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 19 J / g. A packaging material for a power storage device was obtained in the same manner as in Example 3, except that the second resin layer 8 was formed using this resin composition.

<Comparative Example 6>
Except for using the resin composition obtained as follows as the resin composition constituting the second resin layer 8, the exterior material for the electricity storage device having the configuration shown in FIG. Obtained. First, 14 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified olefin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 2 parts by mass of the base resin and 4 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) were melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 158 ° C. A resin composition was obtained by mixing 16 parts by mass of a second elastomer-modified olefin-based resin having a melting energy of 44 J / g. A packaging material for a power storage device was obtained in the same manner as in Example 3, except that the second resin layer 8 was formed using this resin composition.

<Example 29>
A chemical conversion solution consisting of phosphoric acid, polyacrylic acid (acrylic resin), a chromium (III) salt compound, water and alcohol was applied to both sides of a 35 μm-thick aluminum foil 4 and dried at 180 ° C. Then, a chemical conversion film was formed. The amount of chromium adhering to this conversion coating was 10 mg / m ² per one side.

  Next, a biaxially-stretched 6-nylon film 2 having a thickness of 15 μm was dry-laminated (laminated) to one surface of the chemical conversion-treated aluminum foil 4 via a two-component curable urethane-based adhesive 5.

  Next, 14 parts by mass of the first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a second elastomer-modified resin having a melting point of 144 ° C. and a crystal melting energy of 19 J / g. 2 parts by mass of an olefin-based resin and 4 parts by mass of an ethylene-propylene random copolymer (Tmp; 144 ° C., 152 ° C.) were melt-kneaded at 210 ° C. to obtain a first melt-kneaded product. Next, 20 parts by mass of the first melt-kneaded material, 64 parts by mass of a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy of 58 J / g, and a melting point of 144 ° C. By mixing 16 parts by mass of a second elastomer-modified olefin resin having a melting energy of 19 J / g, a resin composition for a second resin layer was obtained.

  Next, an 8 μm thick first resin layer 7 made of an ethylene-propylene random copolymer and a 22 μm thick second resin layer 8 (a second resin layer 8 made of the second resin layer resin composition) are laminated. After a co-extrusion using a T-die to obtain a 30 μm-thick sealant film (first resin layer 7 / second resin layer 8) 3 in which these two layers are laminated, the sealant One of the surfaces of the first resin layer 7 of the film 3 is superposed on the other surface of the dry-laminated aluminum foil 4 via a two-component curable maleic acid-modified polypropylene adhesive 6, and a rubber nip roll is provided. Dry lamination by sandwiching and pressing between a laminating roll heated to 100 ° C., followed by aging (heating) at 50 ° C. for 5 days to obtain the structure shown in FIG. To obtain a sheathing material 1 for a power storage device.

In addition, as the two-component curable maleic acid-modified polypropylene adhesive, 100 parts by mass of maleic acid-modified polypropylene (melting point: 80 ° C., acid value: 10 mg KOH / g) as a main component, and isocyanurate of hexamethylene diisocyanate as a curing agent (NCO content: 20% by mass) 8 parts by mass of an adhesive solution further mixed with a solvent was used, and the adhesive solution was coated on the aluminum foil 4 such that the solid content was 2 g / m ² . After applying to the other surface and drying by heating, it was superimposed on one of the first resin layers 7 of the sealant film 3.

  In Examples 1 to 29 and Comparative Examples 1 to 6, melt kneading was performed by performing melt kneading at 210 ° C. using a 40φ extruder (L / D = 24) equipped with a screw with a tip dalmage and a strand forming die. The obtained strand was water-cooled and solidified in a water tank, and cut with a cutter to obtain a pellet of the first melt-kneaded material (granules having a long diameter of 4 mm to 5 mm).

  In Examples 1 to 29 and Comparative Examples 1 to 6, the first elastomer-modified olefin-based resin was composed of an EPR-modified homopolypropylene and an EPR-modified ethylene-propylene random copolymer, and the second elastomer-modified olefin-based resin was used. Consists of an EPR-modified homopolypropylene and an EPR-modified ethylene-propylene random copolymer. The EPR means ethylene-propylene rubber.

In Tables 1 to 4, the following abbreviations representing the first and second elastomer-modified olefin resins indicate the following resins, respectively.
“B-PP1A”: a first elastomer-modified olefin resin having a melting point of 163 ° C. and a crystal melting energy (ΔHm) of 58 J / g “B-PP1B”: a melting point of 166 ° C. and a crystal melting energy ( ΔHm) is a first elastomer-modified olefin-based resin “B-PP1D” having a melting point of 145 ° C. and a crystal melting energy (ΔHm) is 57 J / g; “B-PP1E”: a first elastomer-modified olefin resin “B-PP2A” having a melting point of 155 ° C. and a crystal melting energy (ΔHm) of 49 J / g; a melting point of 144 ° C., and a crystal melting energy (Δ Hm) is a second elastomer-modified olefin resin “B-PP2B” having a melting point of 136 ° C. and a crystal melting energy of 19 J / g. (△ Hm) is a second elastomer-modified olefin-based resin “B-PP2C” having a melting point of 130 ° C. and a crystal melting energy (△ Hm) of 14 J / g. “B-PP2D”: a second elastomer-modified olefin-based resin having a melting point of 158 ° C. and a crystal melting energy (ΔHm) of 44 J / g.

In the table, the following abbreviations indicate the following resins, respectively.
"EPR" ... ethylene-propylene rubber "EBR" ... ethylene-butene rubber "SEBS" ... styrene-ethylene-butylene-styrene copolymer "homo PP" ... homopolypropylene "r-PPA" ... ethylene-propylene random copolymer ( Melting point: 144 ° C, 152 ° C)
“R-PPB”: an ethylene-propylene random copolymer (melting point: 145 ° C.).

  The “melting point” of each resin is a melting peak temperature (Tmp) measured by differential scanning calorimetry (DSC) in accordance with JIS K7121-1987, and the “crystal melting energy” of each resin is JIS. Heat of fusion (crystal melting energy; ΔHm) measured by differential scanning calorimetry (DSC) in accordance with K7122-1987, all of which are measured under the following measurement conditions.

Temperature rise and fall speed: Temperature rise and fall rate of 10 ° C./min between 23 ° C. and 210 ° C. Sample material: weigh 5 mg Container: Use aluminum pan Equipment: “DSC-60A” manufactured by Shimadzu Corporation

  For each power storage device exterior material obtained as described above, based on the following measurement methods and evaluation methods, measure the seal strength, evaluate the cohesion of the peeled interface when peeled, whitening during molding Was evaluated.

<Seal strength measurement method>
After cutting out two test specimens having a width of 15 mm and a length of 150 mm from the obtained exterior material, the two test specimens were superimposed so as to be in contact with each other's inner sealant layers. Using a heat-sealing device (TP-701-A) manufactured by KK, heat seal temperature is 200 ° C., seal pressure is 0.2 MPa (gauge display pressure), and seal time is 2 seconds. went.

  Next, as for the pair of exterior materials in which the inner sealant layers are heat-sealed to each other as described above, the exterior materials are manufactured using a strograph (AGS-5kNX) manufactured by Shimadzu Access Co., Ltd. in accordance with JIS Z0238-1998. The peel strength at the time when the (test body) was peeled at 90 ° at a pulling speed of 100 mm / min between the inner sealant layers of the seal portion was measured, and this was defined as the seal strength (N / 15 mm width).

  Those having a seal strength of 30 N / 15 mm width or more are judged to be acceptable. It is preferable that the seal strength is 40 N / 15 mm width or more.

<Evaluation method of cohesion degree at peeling interface>
After measuring the above-mentioned seal strength (peeling strength), both sides of the peeled part (destructed part) of the inner sealant layer of the exterior material are visually observed, and the presence or absence and degree (whitening The higher the degree, the higher the degree of aggregation can be determined) was evaluated based on the following criteria.
(Judgment criteria)
A sample having no or no whitening and having a low degree of coagulation having a low degree of coagulation is represented by "x", and a medium having some degree of whitening and having a medium degree of coagulation is represented by "△". A sample having a large value of “” was evaluated as “○”, and a sample having significantly more whitening and a higher degree of aggregation was evaluated as “◎”.

<Evaluation method for whitening during molding>
After deep-drawing the exterior material into a rectangular parallelepiped shape with a depth of 5 mm using the deep-drawing molding tool manufactured by Amada Co., Ltd. under the following molding conditions, the inner surface of the housing recess of the obtained molded body (the inner sealant layer) 3) were visually observed, and the presence or absence and degree of whitening were evaluated based on the following criteria.
(Judgment criteria)
The molded body after the molding was visually observed, and those in which whitening was not observed or almost no whitening were indicated by “◎”, those with little whitening were indicated by “○”, and those in which whitening occurred to some extent Is indicated by "△", and the case where remarkable whitening is caused is indicated by "x".
(Molding condition)
Mold: Punch: 33.3 mm x 53.9 mm, Die: 80 mm x 120 mm, Corner R: 2 mm, Punch R: 1.3 mm, Die R: 1 mm
Wrinkle pressure: Gauge pressure: 0.475 MPa, actual pressure (calculated value): 0.7 MPa
Material: SC (carbon steel) material, chrome plating only on punch R.

<Comprehensive evaluation>
The above three evaluation results were comprehensively evaluated and evaluated on a four-point scale. Particularly excellent in this comprehensive evaluation was “◎”, excellent in overall evaluation was “○”, and overall evaluation was slightly inferior. Were evaluated as "△", and those with poor overall evaluation were evaluated as "x".

  As is clear from the table, the external storage materials for power storage devices of Examples 1 to 29 of the present invention (the external storage materials for power storage devices using the sealant film of the present invention) have sufficient sealing strength, and Since the degree of whitening at the peeling interface was sufficiently large, the degree of cohesion at the peeling interface was high, and cohesive failure occurred inside the sealant layer at the time of peeling, and whitening at the time of molding was sufficiently suppressed. As described above, when the exterior materials for power storage devices of Examples 1 to 29 of the present invention are used, since the cohesive failure occurs inside the sealant layer, the metal foil layer 4 and the inner sealant layer 3 at the time of peeling (breaking). Peeling (destruction) is less likely to occur at the interface of, and therefore, when a peeling point (breaking point) for preventing rupture occurs, there is an advantage that continuous destruction starting from the peeling point (breaking point) does not easily proceed. .

  On the other hand, in Comparative Examples 1 to 6 which deviated from the specified range of the claims of the present invention, the overall evaluation was "x".

  The sealant film for an exterior material of an electricity storage device according to the present invention is used as a sealant film for an exterior material of an electricity storage device such as a storage battery for mobile, a storage battery for a vehicle, a storage battery for regenerative energy recovery, a capacitor (capacitor), and an all-solid battery.

  The exterior material for an electric storage device according to the present invention is used as an exterior material for an electric storage device such as a storage battery for a mobile device, a storage battery for a vehicle, a storage battery for regenerative energy recovery, a capacitor (capacitor), and an all-solid battery.

  The power storage device according to the present invention is used as a mobile storage battery, a vehicle storage battery, a regenerative energy recovery storage battery, a capacitor (capacitor), an all-solid battery, and the like.

DESCRIPTION OF SYMBOLS 1 ... Exterior material for electric storage devices 2 ... Base layer (outer layer)
3: Inner sealant layer (sealant film)
4 ... Metal foil layer 7 ... First resin layer 8 ... Second resin layer 10 ... Outer case (molded body) for power storage device
15 exterior member 30 power storage device 31 power storage device body

Claims (21)

A first resin layer containing 50% by mass or more of a random copolymer containing propylene and other copolymer components other than propylene as a copolymer component,
Two layers including a first elastomer-modified olefin-based resin having a melting point of 163 ° C. or higher and a crystal melting energy of 58 J / g or higher, and a second resin layer formed of a composition including a polymer component Consisting of the above laminate,
The first elastomer-modified olefin-based resin is composed of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer,
The elastomer-modified random copolymer is an elastomer-modified random copolymer containing propylene and other copolymer components other than propylene as a copolymer component,
In the second resin layer, the content of the first elastomer-modified olefin resin is 50%.
Mass% or more,
The polymer component is a random copolymer containing propylene and other copolymer components other than propylene as a copolymer component, homopolypropylene, at least one polymer component selected from the group consisting of olefin-based elastomers and styrene-based elastomers. A sealant film for an exterior material of an electricity storage device. A first resin layer containing 50% by mass or more of a random copolymer containing propylene and other copolymer components other than propylene as a copolymer component,
A first elastomer-modified olefin resin having a melting point of 163 ° C. or more and a crystal melting energy of 58 J / g or more, and a first elastomer-modified olefin resin having a melting point of 135 ° C. or more and a crystal melting energy of 3
A second resin layer formed of a composition containing a second elastomer-modified olefin-based resin of 0 J / g or less and a polymer component, and a laminate of two or more layers,
The first elastomer-modified olefin-based resin is composed of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer,
The second elastomer-modified olefin-based resin is composed of an elastomer-modified homopolypropylene or / and an elastomer-modified random copolymer,
The elastomer-modified random copolymer is an elastomer-modified random copolymer containing propylene and other copolymer components other than propylene as a copolymer component,
In the second resin layer, the total value of the content of the first elastomer-modified olefin-based resin and the content of the second elastomer-modified olefin-based resin is 50% by mass or more,
The polymer component is a random copolymer containing propylene and other copolymer components other than propylene as a copolymer component, homopolypropylene, at least one polymer component selected from the group consisting of olefin-based elastomers and styrene-based elastomers. A sealant film for an exterior material of an electricity storage device. 3. The sealant film according to claim 2, wherein the content of the second elastomer-modified olefin-based resin in the second resin layer is 1% by mass to 50% by mass. 4. The sealant film for an exterior material of an electric storage device according to claim 2 or 3, wherein the second elastomer-modified olefin-based resin has two or more crystallization peaks in a DSC measurement graph. The sealant film for an exterior material of an electric storage device according to any one of claims 1 to 4, wherein the content of the polymer component in the second resin layer is 1% by mass or more and less than 50% by mass. The elastomer in the elastomer-modified homopolypropylene is ethylene propylene rubber,
The sealant film for an exterior material of an electricity storage device according to any one of claims 1 to 5, wherein the elastomer in the elastomer-modified random copolymer is ethylene propylene rubber. The first resin layer further contains an antiblocking agent and a slip agent,
The sealant film for an exterior material of an electricity storage device according to any one of claims 1 to 6, wherein the resin layer further contains a slip agent. The sealant film for an exterior material of an electricity storage device according to any one of claims 1 to 7, comprising only the first resin layer and a second resin layer laminated on one surface of the first resin layer. At least three layers including the second resin layer, a first resin layer laminated on one surface of the second resin layer, and a first resin layer laminated on the other surface of the second resin layer The sealant film for an exterior material of an electricity storage device according to any one of claims 1 to 7, wherein the sealant film comprises a laminate in which is laminated. A base material layer as an outer layer, and an inner sealant layer composed of the sealant film according to any one of claims 1 to 9, and a metal foil layer disposed between these two layers,
The exterior material for a power storage device, wherein the first resin layer is disposed on an innermost layer side in the inner sealant layer. An outer case for a power storage device, comprising a molded product of the outer material for a power storage device according to claim 10. A method for manufacturing an outer case for an electricity storage device, comprising deep-drawing or bulging the exterior material for an electricity storage device according to claim 10. A power storage device body,
An exterior member comprising the exterior material for an electricity storage device according to claim 10 and / or the exterior case for an electricity storage device according to claim 11,
The power storage device, wherein the power storage device main body is exteriorly covered with the exterior member. A pre-melt kneading step of melt-kneading one or more elastomer components and one or more plastomer components to obtain a first melt-kneaded product;
The first melt-kneaded product having a melting point of 163 ° C. or more and a crystal melting energy of 58 J /
g of a first elastomer-modified olefin-based resin having a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g or less;
And a step of obtaining a resin composition by mixing the resin composition with a resin composition. The elastomer component used in the preliminary melt-kneading step is an olefin-based elastomer,
1 selected from the group consisting of a styrene-based elastomer and a second elastomer-modified olefin-based resin having a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g or less.
The method for producing a resin composition for a sealant film of an exterior material for an electric storage device according to claim 14, which is a kind or two or more kinds of elastomer components. The plastomer component used in the preliminary melting and kneading step is a random polypropylene, a homopolypropylene, having a melting point of 163 ° C. or more and a crystal melting energy of 58 J.
The production of a resin composition for a sealant film of an exterior material for an electric storage device according to claim 14 or 15, wherein the resin composition is one or more plastomer components selected from the group consisting of a first elastomer-modified olefin-based resin having a mass of at least 1 g / g. Method. The elastomer component used in the preliminary melt-kneading step is a second elastomer-modified olefin-based resin having a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g or less,
The plastomer component used in the preliminary melt-kneading step contains a first elastomer-modified olefin resin having a melting point of 163 ° C. or more and a crystal melting energy of 58 J / g or more, and further comprises random polypropylene or / and homopolypropylene. The method for producing a resin composition for a sealant film of an exterior material for an electric storage device according to claim 14, comprising: A pre-melt kneading step of melt-kneading one or more elastomer components and one or more plastomer components to obtain a first melt-kneaded product;
The first melt-kneaded product having a melting point of 163 ° C. or more and a crystal melting energy of 58 J /
g of a first elastomer-modified olefin-based resin having a weight of at least g, to obtain a resin composition, the method comprising the steps of: The elastomer component used in the preliminary melt-kneading step is an olefin-based elastomer,
1 selected from the group consisting of a styrene-based elastomer and a second elastomer-modified olefin-based resin having a melting point of 135 ° C. or more and a crystal melting energy of 30 J / g or less.
19. The method for producing a resin composition for a sealant film of an exterior material for an electric storage device according to claim 18, wherein the resin composition is a kind or two or more kinds of elastomer components. The plastomer component used in the preliminary melting and kneading step is a random polypropylene, a homopolypropylene, having a melting point of 163 ° C. or more and a crystal melting energy of 58 J.
20. The production of a resin composition for a sealant film of an exterior material for an electric storage device according to claim 18 or 19, wherein the resin composition is one or more plastomer components selected from the group consisting of a first elastomer-modified olefin-based resin having a mass of at least 1 g / g. Method. The sealant film for an exterior material of an electric storage device according to any one of claims 14 to 20, wherein in the preliminary melting and kneading step, a mixing mass ratio of an elastomer component / plastomer component is set in a range of 5/95 to 70/30. A method for producing a resin composition.

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