Complex

Abstract

SOLUTION: A composite body comprises: a composition layer (I) formed of a composition (Ia); and a metal layer (II) contacting the composition layer (I). The composition (Ia) has a content ratio of a propylene-based polymer (A) containing 75-100 mol% of a propylene-derived constitutional unit being 45-75 pts.mass and a content ratio of an ethylenic polymer (B) being 0-20 pts.mass, and contains a copolymer which has 60 mol% or more, and 99 mol% or less of a 4-methyl-1-pentene-derived constitutional unit; 1 mol% or more and 40 mol% or less of an α-olefin-derived constitutional unit having 2 or more and 20 or less carbon atoms other than the 4-methyl-1-pentene. in which the total of the 4-methyl-1-pentene-derived constitutional unit and the α-olefin-derived constitutional unit having 2 or more and 20 or less carbon atoms other than the 4-methyl-1-pentene, is 100 mol%. The composition (Ia) is also a resin composition that has a melting point Tm measured with a differential scanning calorimeter (DSC) is 199°C or lower or a content ratio of a thermoplastic resin (C) that is not substantially observed is 15-45 pts.mass (with respect to the total of the components (A), (B) and (C) being 100 pts.mass).EFFECT: There are provided: a polyolefin resin composition layer which enables satisfactory bonding between a polymethyl pentene resin, and a polyolefin resin such as a polypropylene resin through coextrusion molding, and is excellent in peeling strength with a metal layer; and a composite body thereof.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a composite having a composition layer containing a propylene-based polymer and a metal layer. [Background technology]

[0002] Polypropylene has been widely used as a thermoplastic molding material with excellent rigidity, heat resistance, and transparency. Since polypropylene is a non-polar material, it has poor adhesion to metal materials such as aluminum. To improve adhesion, a technique for modifying polypropylene with an unsaturated carboxylic acid or its derivative is widely known.

[0003] In addition, since polypropylene has poor flexibility, when polypropylene is used as an adhesive resin, a soft rubber component is usually blended into the polypropylene. A polypropylene-based adhesive resin with improved adhesiveness has been proposed by blending a soft rubber component into the polypropylene (Patent Document 1).

[0004] Meanwhile, for secondary batteries such as lithium-ion batteries, metal cans have been used. In recent years, in response to the demand for thinner and more diverse products, laminate packaging materials have been used, in which a composite of aluminum foil and a resin film laminated thereon is formed into a bag shape. Metal lead substrates such as aluminum and nickel are attached to the metal substrates of the positive and negative electrodes of lithium-ion batteries to extract electricity. In order to prevent short circuits between the lead substrate and the aluminum foil of the laminate packaging material and leakage of electrolyte, it has become common to sandwich and seal a film-shaped insulator (tab lead film) in the sealing portion of the lead substrate in order to improve the sealing strength between the lead substrate and the innermost resin layer (sealant) of the laminate packaging material (Patent Document 2 and Patent Document 3).

[0005] In addition, a film for battery components has been disclosed, which includes a fibrous sheet or porous sheet containing a 4-methyl-1-pentene polymer and a layer made of a modified polyolefin, and it is described that a film for battery components such as a tab lead film can be obtained that can be produced without a crosslinking process while maintaining heat resistance, flexibility, adhesive strength to electrodes, and interlayer adhesive strength equivalent to or greater than conventional products (Patent Document 4). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 04-300933 [Patent Document 2] Japanese Patent Application Publication No. 56-071278 [Patent Document 3] JP 2001-102016 A [Patent Document 4] JP 2016-026380 A Summary of the Invention [Problem to be solved by the invention]

[0007] Tab lead films need to have high insulation properties, as well as excellent peel strength against the lead substrate. For example, in recent years, there has been active research into large-scale, high-capacity lithium-ion batteries for use in automobiles, and improvements in heat resistance and peel strength are required.

[0008] Although polymethylpentene resin has high heat resistance, it is necessary to use an adhesive to bond it to the lead substrate and polypropylene-based resin. Furthermore, when using polypropylene-based adhesive resin for bonding, there is a problem that polymethylpentene resin, which is non-polar and has low wettability, has low peel strength and is prone to peeling in co-extrusion molding, so it is necessary to make it into a fibrous sheet or porous sheet before extrusion coating the polypropylene-based adhesive resin.

[0009] The present invention has been made in view of the above problems, and has an object to provide a composite material having excellent peel strength between a polymethylpentene resin and a polypropylene-based adhesive resin layer and a metal layer, which is produced by coextrusion molding. [Means for solving the problem]

[0010] [1] A composition layer (I) formed from a composition (Ia); a metal layer (II) in contact with the composition layer (I); is a complex having The composition (Ia) comprises the content ratio of the propylene-based polymer (A) containing 75 to 100 mol % of structural units derived from propylene is 45 to 75 parts by mass, The content of the ethylene polymer (B) is 0 to 20 parts by mass, The resin composition contains a copolymer having 60 mol % or more and 99 mol % or less of structural units derived from 4-methyl-1-pentene and 1 mol % or more and 40 mol % or less of structural units derived from an α-olefin having 2 to 20 carbon atoms other than 4-methyl-1-pentene, and the structural units derived from the 4-methyl-1-pentene and the structural units derived from the α-olefin having 2 to 20 carbon atoms other than 4-methyl-1-pentene are 100 mol % in total, and the content of a thermoplastic resin (C) having a melting point Tm of 199°C or less or substantially no melting point measured by a differential scanning calorimeter (DSC) is 15 to 45 parts by mass (wherein the total of the components (A), (B) and (C) is taken as 100 parts by mass). Complex. [2] The composite according to [1], wherein a part or all of the copolymers contained in the propylene-based polymer (A), the ethylene-based polymer (B), and the thermoplastic resin (C) are graft-modified with an unsaturated carboxylic acid and / or a derivative thereof. [3] The composite according to [1] or [2], further comprising a polyolefin resin layer (III) formed on a surface of the composition layer (I) that is not in contact with the metal layer (II). [4] The composite according to [3], further comprising the composition layer (I) formed on a surface of the polyolefin resin layer (III) that is not in contact with the metal layer (II). [5] The composite according to any one of [1] to [4], wherein the polyolefin resin layer (III) contains a polymer in which a content ratio of structural units derived from 4-methyl-1-pentene to all structural units is 90 mol% or more and 100 mol% or less, and a content ratio of structural units derived from α-olefins other than 4-methyl-1-pentene to all structural units is 0 mol% or more and 10 mol% or less, and the ... composite contains a thermoplastic resin having a melting point Tm of 200°C or more as measured by differential scanning calorimetry (DSC). [6] The composite according to any one of [1] to [5], wherein the composition (Ia) further contains a carbodiimide-modified polyolefin (D), and in the composition (Ia), the content of component (A) is 45 to 65 parts by mass, the content of component (B) is 0 to 20 parts by mass, the content of component (C) is 15 to 45 parts by mass, and the content of component (D) is 5 to 30 parts by mass, per 100 parts by mass in total of the components (A), (B), (C), and (D). [7] A tab lead for a lithium ion battery, comprising the composite according to any one of [1] to [6]. [8] A lithium-ion battery having the tab lead described in [7]. Effect of the Invention

[0011] According to the present invention, it is possible to provide a polyolefin resin composition layer which can be well bonded to a polymethylpentene resin and a polyolefin resin such as a polypropylene resin by coextrusion molding and further has excellent peel strength with a metal layer, and a composite thereof. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing one embodiment of the complex of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described. In this specification, a numerical range expressed using "to" means a range including the numerical values ​​before and after "to" as the lower and upper limits.

[0014] [Complex] The complex of the present invention is A composition layer (I) formed from a composition (Ia); a metal layer (II) in contact with the composition layer (I); has.

[0015] <Composition layer (I)> The composition layer (I) is formed from a composition (Ia). The composition (Ia) contains a propylene-based copolymer (A) and a thermoplastic resin (C), and may further contain an ethylene-based polymer (B). The composition (Ia) may further contain a carbodiimide-modified polyolefin (D).

[0016] Hereinafter, the propylene-based copolymer (A), the ethylene-based polymer (B), the thermoplastic resin (C) and the carbodiimide-modified polyolefin (D) will also be referred to as component (A), component (B), component (C) and component (D), respectively.

[0017] The composition layer (I) has high insulating properties and is excellent in peel strength with respect to the metal layer (II). For this reason, the composition layer (I) is preferable as a tab lead film for metallic lead substrates of positive and negative electrodes in laminate packaging materials for lithium ion batteries, for example.

[0018] Propylene polymer (A) The propylene polymer (A) may be an isotactic polypropylene or a syndiotactic polypropylene. The propylene polymer (A) may be a homopolypropylene, or a random copolymer or a block copolymer of propylene and an α-olefin having 2 to 20 carbon atoms (excluding propylene). Specific examples of the α-olefin include ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, and 4-methyl-1-pentene, and may be a combination of two or more of these.

[0019] Particularly from the viewpoint of heat resistance, ethylene and 1-butene are preferred. The propylene polymer (A) contains 75 to 100 mol %, preferably 85 to 100 mol %, and more preferably 90 to 100 mol %, of structural units derived from propylene.

[0020] As the propylene-based polymer (A), the above polymers may be used alone or in combination. The propylene polymer (A) preferably has a density of 0.860 to 0.910 g / cm 3 , more preferably 0.875 to 0.910 g / cm 3 , and more preferably 0.885 to 0.910 g / cm 3 When it is in the above range, the heat resistance is excellent.

[0021] The propylene polymer (A) has a melt flow rate (MFR) of preferably 0.1 to 100 g / 10 min, more preferably 0.2 to 50 g / 10 min, and further preferably 0.3 to 30 g / 10 min at a temperature of 230° C. and a load of 2.16 kg, measured according to ASTM D 1238. When the MFR is within the above range, the polymer is excellent in moldability and sealability.

[0022] Ethylene polymer (B) The ethylene polymer (B) is a homopolymer of ethylene or a copolymer of ethylene and an α-olefin. The α-olefin may be an α-olefin having 3 or more carbon atoms, preferably 3 to 10 carbon atoms, and specifically may be propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 4-methyl-1-pentene, or a combination of two or more of these. The copolymerization amount of the α-olefin is usually 25 mol% or less. When it is within the above range, it is excellent in terms of flexibility.

[0023] The ethylene polymer (B) preferably has a density of 0.855 to 0.970 g / cm 3 , more preferably 0.860 to 0.940 g / cm 3 , and more preferably 0.865 to 0.930 g / cm 3 When the thickness is in the above range, the flexibility is excellent.

[0024] The ethylene polymer (B) preferably has a melt flow rate (MFR) of 0.1 to 20 g / 10 min, more preferably 0.3 to 16 g / 10 min, and even more preferably 0.5 to 10 g / 10 min, at a temperature of 190° C. and a load of 2.16 kg, measured according to ASTM D 1238. When the MFR is within the above range, the polymer is excellent in moldability and sealability.

[0025] Thermoplastic resin (C) The thermoplastic resin (C) contains structural units derived from 4-methyl-1-pentene and structural units derived from an α-olefin other than 4-methyl-1-pentene and having from 2 to 20 carbon atoms, and includes a copolymer in which the structural units derived from 4-methyl-1-pentene and the structural units derived from the α-olefin other than 4-methyl-1-pentene and having from 2 to 20 carbon atoms account for 100 mol % in total.

[0026] Examples of the α-olefin having 2 to 20 carbon atoms other than 4-methyl-1-pentene include ethylene, propylene, 1-butene, 1-hexene, 1-octene, 1-decene, 1-tetradecene, and 1-octadecene. The α-olefin is preferably ethylene, propylene, 1-butene, 1-hexene, 1-octene, or 1-decene, more preferably ethylene, propylene, 1-butene, 1-hexene, or 1-octene, and even more preferably ethylene, propylene, 1-butene, or 1-hexene. The α-olefin may be used alone or in combination of two or more thereof.

[0027] In the copolymer, the content of the structural units derived from 4-methyl-1-pentene is 60 mol% or more and 99 mol% or less, preferably 63 mol% or more and 98 mol% or less, more preferably 65 mol% or more and 95 mol% or less, even more preferably 65 mol% or more and 90 mol% or less, and particularly preferably 65 mol% or more and 87 mol% or less. The content of the structural units derived from α-olefins having 2 to 20 carbon atoms other than 4-methyl-1-pentene is 1 mol% or more and 40 mol% or less, preferably 2 mol% or more and 37 mol% or less, more preferably 5 mol% or more and 35 mol% or less, even more preferably 10 mol% or more and 35 mol% or less, and particularly preferably 13 mol% or more and 35 mol% or less. When the amount of the structural units is within the above range, the obtained composition has excellent heat resistance and adhesive strength.

[0028] The copolymer preferably has a melt flow rate (MFR) in the range of 0.5 to 50 / 10 min, more preferably 0.5 to 30 g / 10 min, at a temperature of 230° C. and a load of 2.16 kg, according to ASTM D 1238. When the MFR is in the above range, the copolymer has excellent moldability.

[0029] The thermoplastic resin (C) preferably has a density of 0.825 to 0.870 g / cm 3 , more preferably 0.827 to 0.860 g / cm 3 , and more preferably 0.830 to 0.850 g / cm3 When the thickness is in the above range, a good balance between flexibility and handleability is achieved. The thermoplastic resin (C) has a melting point Tm of 199° C. or lower, or substantially no melting point Tm as measured by differential scanning calorimetry (DSC).

[0030] Carbodiimide modified polyolefin (D) The carbodiimide-modified polyolefin (D) is a reaction product between a polyolefin (a) having a group reactive with a carbodiimide group and a carbodiimide group-containing compound (b).

[0031] By containing the carbodiimide-modified polyolefin (D) in the adhesive resin composition of the present invention, the adhesive resin composition of the present invention contains a carbodiimide group. The number of carbodiimide groups in one molecule of the carbodiimide-modified polyolefin (D) is preferably 5 or more, more preferably 10 or more. The upper limit of the number of carbodiimide groups is not particularly limited as long as the effects of the present invention are achieved, but is usually 30.

[0032] (Polyolefin (a)) The polyolefin (a) having a group reactive with a carbodiimide group can be obtained by introducing a compound (m) having a group reactive with a carbodiimide group into a polyolefin. The polyolefin (a) may be used alone or in combination of two or more kinds.

[0033] Examples of the compound (m) include compounds having a group having active hydrogen that is reactive with a carbodiimide group. Specific examples include compounds having a group derived from carboxylic acid, amine, alcohol, thiol, etc. Among these, compounds having a group derived from carboxylic acid are preferably used, and unsaturated carboxylic acid and / or its derivatives are particularly preferred. In addition to compounds having a group having active hydrogen, compounds having a group that is easily converted into a group having active hydrogen by water or the like can also be preferably used. Specific examples include compounds having an epoxy group and compounds having a glycidyl group. Compound (m) may be used alone or in combination of two or more.

[0034] When an unsaturated carboxylic acid and / or its derivative is used as the compound (m), it may be an unsaturated compound having one or more carboxylic acid groups and its derivative, preferably an unsaturated compound having one or more carboxylic acid anhydride groups and its derivative. Examples of the unsaturated group include a vinyl group, a vinylene group, and an unsaturated cyclic hydrocarbon group. Specific examples of the compound include unsaturated carboxylic acids such as (meth)acrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, norbornene dicarboxylic acid, and bicyclo[2.2.1]hept-2-ene-5,6-dicarboxylic acid, their acid anhydrides, and their derivatives (e.g., acid halides, amides, imides, esters, etc.). Specific acid anhydrides and derivatives include, for example, maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2.2.1]hept-2-ene-5,6-dicarboxylic anhydride; malenyl chloride; malenylimide; dimethyl maleate, monomethyl maleate, diethyl maleate, diethyl fumarate, dimethyl itaconate, diethyl citracone, dimethyl tetrahydrophthalate, dimethyl bicyclo[2.2.1]hept-2-ene-5,6-dicarboxylate, hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate, glycidyl(meth)acrylate, aminoethyl(meth)acrylate, and aminopropyl(meth)acrylate.

[0035] When using an unsaturated carboxylic acid and / or its derivative as compound (m), one or more of them may be used alone. Among these, maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2.2.1]hept-2-ene-5,6-dicarboxylic anhydride, (meth)acrylic acid, hydroxyethyl (meth)acrylate, glycidyl methacrylate, and aminopropyl methacrylate are preferred. Furthermore, dicarboxylic anhydrides such as maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, and bicyclo[2.2.1]hept-2-ene-5,6-dicarboxylic anhydride are particularly preferred.

[0036] The method of introducing the compound (m) into the polyolefin may be any known method, for example, a method of graft copolymerizing the compound (m) onto the polyolefin main chain, or a method of radically copolymerizing the olefin and the compound (m). The following will specifically explain the graft copolymerization and the radical copolymerization separately.

[0037] <Graft copolymerization> The polyolefin (a) having a group reactive with a carbodiimide group can be obtained by graft copolymerizing a compound (m) having a group reactive with a carbodiimide group in the polyolefin main chain, and, if necessary, other ethylenically unsaturated monomers, etc., in the presence of a radical initiator.

[0038] <Polyolefin main chain> The polyolefin used as the polyolefin main chain is a polymer mainly composed of an aliphatic α-olefin having 2 to 20 carbon atoms, a cyclic olefin, or a non-conjugated diene, preferably an aliphatic α-olefin having 2 to 10 carbon atoms, more preferably an aliphatic α-olefin having 2 to 8 carbon atoms. These olefins may be used alone or in combination of two or more. In the case of a copolymer, the content of the olefin as a comonomer is not particularly limited as long as the effects of the present invention are exhibited, but is usually 50 mol% or less, preferably 40 mol% or less, and more preferably 30 mol% or less. Among the polyolefins in this range, crystalline polyolefins such as polyethylene, polypropylene, polybutene-1, poly-4-methyl-1-pentene, and α-olefin copolymers of ethylene, propylene, butene-1, or 4-methyl-1-pentene and a comonomer are preferred, and polyethylene, polypropylene, or propylene-ethylene copolymers are more preferred. In addition, both isotactic and syndiotactic structures can be used, and there is no particular restriction on the stereoregularity.

[0039] The density of the polyolefin used for graft modification (measured in accordance with JIS K7112) is not particularly limited as long as the effects of the present invention are exhibited, but is usually 0.8 to 1.1 g / cm 3 , preferably 0.8 to 1.05 g / cm 3 , more preferably 0.8 to 1.0 g / cm 3 The melt flow rate (MFR) at 230°C under a load of 2.16 kg according to ASTM D1238 is not particularly limited as long as the effects of the present invention are achieved, but is usually 0.01 to 500 g / 10 min, preferably 0.05 to 200 g / 10 min, and more preferably 0.1 to 100 g / 10 min. If the density and MFR are within this range, the density and MFR of the graft copolymer after modification will also be approximately the same, making it easy to handle.

[0040] The degree of crystallinity of the polyolefin used for graft modification is not particularly limited as long as the effects of the present invention are achieved, but is usually 2% or more, preferably 5% or more, and more preferably 10% or more. If the degree of crystallinity is within this range, the graft copolymer after modification is excellent in handleability.

[0041] The number average molecular weight (Mn) of the polyolefin used for graft modification, measured by gel permeation chromatography (GPC), is preferably 5,000 to 500,000, more preferably 10,000 to 100,000. If the number average molecular weight (Mn) is within this range, handling is excellent. In addition, in the case of ethylene-based polyolefins, the number average molecular weight can be calculated in terms of polyethylene if the comonomer amount is 10 mol% or less, and in terms of ethylene-propylene (based on an ethylene content of 70 mol%) if the comonomer amount is 10 mol% or more.

[0042] The polyolefin used for graft modification can be produced by any conventional method, for example, a titanium catalyst, a vanadium catalyst, a metallocene catalyst, etc. can be used to polymerize the olefin. The polyolefin used for graft modification can be in the form of either a resin or an elastomer, and both isotactic and syndiotactic structures can be used, and there is no particular restriction on the stereoregularity. It is also possible to use a commercially available resin as it is.

[0043] Graft Polymerization Method The method for grafting the compound (m) onto the polyolefin main chain is not particularly limited, and any of the conventionally known graft polymerization methods such as a solution method and a melt kneading method can be used.

[0044] The graft amount of the compound (m) is usually 0.05 to 20% by weight, preferably 0.05 to 10% by weight, more preferably 0.05 to 5% by weight, and further preferably 0.05 to 3% by weight, based on 100% by weight of the polyolefin (a). The graft amount of the compound (m) is a net graft amount measured after removing the free compound (m) from the polyolefin (a). The graft amount is, 13 C-NMR, 1 It can be measured by known means such as H-NMR measurement. When a monomer having an acidic functional group such as an unsaturated carboxylic acid and its acid anhydride is used as the compound (m), the acid value can be used as an indicator of the amount of functional group introduced into the polyolefin (a). When maleic anhydride is used as the compound (m), the graft amount can be measured using an infrared spectrophotometer based on the absorption spectrum of the carbonyl group of maleic anhydride, which is usually detected around 1780 to 1790 cm-1.

[0045] <Radical copolymerization> The polyolefin (a) having a group reactive with a carbodiimide group can also be obtained by radical copolymerization of an olefin and a compound (m) having a group reactive with a carbodiimide group. The olefin can be the same as the olefin used to form the polyolefin main chain described above. The method of copolymerizing the olefin and the compound (m) is not particularly limited, and any conventionally known radical copolymerization method can be used.

[0046] (Constitution of polyolefin (a)) The amount of structural units (e.g., structural unit amount, graft amount) derived from the compound (m) having a group reactive with a carbodiimide group in the polyolefin (a) having a group reactive with a carbodiimide group is usually 0.05 to 20% by weight, preferably 0.05 to 5% by weight, and more preferably 0.05 to 3% by weight. If the amount of structural units derived from the compound (m) having a group reactive with a carbodiimide group is within the above range, the polyolefin (a) and the carbodiimide group-containing compound (b) are suitably crosslinked, making it possible to produce an adhesive, which is preferable. If it is below the above range, the adhesive strength may be insufficient.

[0047] The density of the polyolefin (a) having a group reactive with a carbodiimide group (measured in accordance with JIS K7112) is usually 0.870 to 0.940 g / cm 3 , preferably 0.875 to 0.940 g / cm 3 , more preferably 0.880 to 0.940 g / cm 3 It is.

[0048] (Carbodiimide group-containing compound (b)) The carbodiimide group-containing compound (b) is, for example, a polycarbodiimide having a repeating unit represented by general formula (2). The carbodiimide group-containing compound (b) may be used alone or in combination of two or more kinds.

[0049] [ka] In formula (2), R1 represents a divalent organic group having 2 to 40 carbon atoms.

[0050] Polycarbodiimide can be produced by carrying out a decarboxylation condensation reaction of an organic diisocyanate such as an aliphatic diisocyanate, an aromatic diisocyanate, or an alicyclic diisocyanate in the presence of a condensation catalyst without a solvent or in an inert solvent. For example, diisocyanates such as hexamethylene diisocyanate, 4,4-diphenylmethane diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate, xylylene diisocyanate, cyclohexane-1,4-diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, and isophorone diisocyanate are used alone or in combination. In the decarboxylation condensation reaction, the degree of polymerization of the polycarbodiimide can be adjusted by selecting a catalyst, reaction temperature, end-capping agent, etc. The degree of polymerization is usually 2 to 40, preferably 4 to 20. Examples of the terminal blocking agent that can be used include monoisocyanates such as phenyl isocyanate, tolyl isocyanate, naphthyl isocyanate, etc., and active hydrogen-containing compounds such as methanol, ethanol, diethylamine, cyclohexylamine, succinic acid, benzoic acid, ethyl mercaptan, etc. Examples of the condensation catalyst that can be used include alcoholates of titanium, hafnium, zirconium, sodium, calcium, etc., and organic phosphorus compounds such as phosphorene oxide.

[0051] The number average molecular weight (Mn) of the carbodiimide group-containing compound (b) calculated as polystyrene equivalent by gel permeation chromatography (GPC) is not particularly limited as long as the effects of the present invention are exhibited, but is usually 400 to 500,000, preferably 700 to 10,000, more preferably 1,000 to 8,000, and even more preferably 1,000 to 4,000. If the number average molecular weight (Mn) is within this range, the adhesive strength of the adhesive is excellent, which is preferable.

[0052] The carbodiimide group-containing compound (b) may contain a monocarbodiimide in a polycarbodiimide, and it is also possible to use a single compound or a mixture of a plurality of compounds. In the present invention, commercially available carbodiimide group-containing compounds can be used as they are. Examples of commercially available carbodiimide group-containing compounds include Carbodilite (registered trademark) HMV-8CA, HMV-15CA, and Carbodilite (registered trademark) LA1 manufactured by Nisshinbo Chemical Inc.

[0053] In addition, in the present invention, the more the number of carbodiimide groups in one molecule of the carbodiimide group-containing compound (b), the more reaction sites with the polar resin and the resin such as polyketone are, so that the layer containing the polar resin and the layer containing the resin such as polyketone can be more firmly bonded to the layer made of the adhesive of the present invention. For this reason, it is preferable to use a carbodiimide group-containing compound (b) having 5 or more carbodiimide groups in one molecule, and it is more preferable to use a carbodiimide group-containing compound (b) having 10 or more carbodiimide groups in one molecule. The upper limit of the number of carbodiimide groups in one molecule is not particularly limited as long as the effects of the present invention are achieved, but if the number of carbodiimide groups in one molecule increases, a crosslinked structure via the carbodiimide group-containing compound (b) is easily formed, which may deteriorate the moldability, so that 30 is preferable.

[0054] The content of the carbodiimide group in the carbodiimide group-containing compound (b) is 13 It can be measured by C-NMR, IR, titration, etc., and can be understood as the carbodiimide group equivalent. 13 130-142 ppm for C-NMR and 2130-2140 cm for IR -1 It is possible to observe peaks at

[0055] 13 C-NMR measurement is carried out, for example, as follows. That is, 0.35 g of a sample is heated and dissolved in 2.0 ml of hexachlorobutadiene. After filtering this solution through a glass filter (G2), 0.5 ml of deuterated benzene is added and the solution is placed in an NMR tube with an inner diameter of 10 mm. Then, the sample is subjected to measurement at 120° C. using a GX-500 NMR measurement device manufactured by JEOL Ltd. 13 C-NMR measurement is performed. The number of measurements is set to 10,000 or more.

[0056] (Method of preparing polyolefins) The carbodiimide-modified polyolefin (D) is obtained by reacting a polyolefin (a) having a group reactive with a carbodiimide group with a carbodiimide group-containing compound (b), preferably at a temperature of 230° C. or higher. The adhesive containing the polyolefin can be obtained by melt kneading, such as melt modification, but is not limited to this method.

[0057] An example of melt kneading is shown below. The reaction method is not particularly limited, but may be, for example, a method in which polyolefin (a) and carbodiimide group-containing compound (b) are charged and kneaded in a Henschel mixer, V-type blender, tumbler blender, ribbon blender, etc., and then melt kneaded in a single screw extruder, multi-screw extruder, kneader, Banbury mixer, etc. Among these, it is preferable to use a device with excellent kneading performance such as a multi-screw extruder, kneader, Banbury mixer, etc., since an adhesive in which each component is more uniformly dispersed and reacted can be obtained.

[0058] The polyolefin (a) and the carbodiimide group-containing compound (b) can be mixed in advance and then fed from a hopper, or a portion of the components can be fed from a hopper and the other components can be fed from a feed port located anywhere between the vicinity of the hopper and the tip of the extruder.

[0059] The temperature at which the above components are melted and kneaded can be equal to or higher than the highest melting point of the components to be mixed, and specifically, the temperature is usually in the range of 180 to 320°C, preferably 230 to 300°C, and more preferably 235 to 280°C.

[0060] Composition (Ia) In the composition (Ia), a part or all of the copolymers contained in the propylene-based polymer (A), the ethylene-based polymer (B) and the thermoplastic resin (C) may be graft-modified with an unsaturated carboxylic acid and / or a derivative thereof. That is, any one or two of the components (A), (B) and (C) may be graft-modified, or all three components may be graft-modified. Also, each of the components (A), (B) and (C) may be graft-modified only partially or entirely.

[0061] Graft modification can generally be carried out by grafting an unsaturated carboxylic acid and / or its derivative to a base polymer. Examples of unsaturated carboxylic acids include maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, nadic acid (registered trademark of endo-cis-bicyclo "2,2,1" hept-5-ene-2,3-dicarboxylic acid), acrylic acid, and methacrylic acid. Examples of derivatives of unsaturated carboxylic acids include acid anhydrides, imides, amides, and esters of the unsaturated carboxylic acids, and specific examples thereof include maleimide, maleic anhydride, citraconic anhydride, monomethyl maleate, and glycidyl maleate. Among these, unsaturated carboxylic acids or their acid anhydrides are preferred, and maleic acid, nadic acid, and their acid anhydrides are particularly preferred. When using unsaturated carboxylic acids and / or their derivatives, they may be used alone or in combination of two or more.

[0062] A conventionally known method can be used for the graft reaction. For example, when a propylene-based polymer is used as the base polymer, for example, a method is used in which a propylene-based polymer is dissolved in an organic solvent, and then an unsaturated carboxylic acid or its derivative and a radical initiator such as an organic peroxide are added to the obtained solution, and the mixture is reacted for 0.5 to 15 hours, preferably 1 to 10 hours, at a temperature of usually 60 to 350°C, preferably 80 to 190°C. Alternatively, a method is also possible in which a propylene-based polymer, an unsaturated carboxylic acid or its derivative and a radical initiator such as an organic peroxide are added without a solvent using an extruder, and the mixture is reacted for 0.5 to 10 minutes at a temperature above the melting point of the propylene-based polymer, preferably 120 to 350°C.

[0063] As the radical initiator, organic peroxides such as dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexyne-3,2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, and 1,4-bis(tert-butylperoxyisopropyl)benzene are preferred.

[0064] The amount of modification by the graft modification is preferably 0.01 to 10 mass%, more preferably 0.1 to 5 mass%, and further preferably 1 to 5 mass%, in terms of the weight of the graft monomer. When the amount of graft modification is within the above range, the interlayer adhesion of the obtained laminate is good.

[0065] In composition (Ia), in a total of 100 parts by mass of the components (A), (B), and (C), the proportion of component (A) is 45 to 75 parts by mass, the proportion of component (B) is 0 to 20 parts by mass, and the proportion of component (C) is 15 to 45 parts by mass, preferably the proportion of component (A) is 47 to 72 parts by mass, the proportion of component (B) is 7 to 20 parts by mass, and the proportion of component (C) is 17 to 42 parts by mass, and more preferably the proportion of component (A) is 50 to 70 parts by mass, the proportion of component (B) is 10 to 20 parts by mass, and the proportion of component (C) is 20 to 40 parts by mass.

[0066] In the composition (Ia), when the component (D) is contained, the proportion of the component (A) is 45 to 65 parts by mass, the proportion of the component (B) is 0 to 20 parts by mass, the proportion of the component (C) is 15 to 45 parts by mass, and the proportion of the component (D) is 5 to 30 parts by mass, preferably the proportion of the component (A) is 45 to 60 parts by mass, the proportion of the component (B) is 5 to 17 parts by mass, the proportion of the component (C) is 17 to 42 parts by mass, and the proportion of the component (D) is 10 to 30 parts by mass, and more preferably the proportion of the component (A) is 45 to 55 parts by mass, the proportion of the component (B) is 7 to 17 parts by mass, the proportion of the component (C) is 20 to 40 parts by mass, and the proportion of the component (D) is 10 to 25 parts by mass, based on 100 parts by mass in total of the components (A), (B), (C), and (D).

[0067] The composition (Ia) preferably has a melt flow rate (MFR) in the range of 0.3 to 20 g / 10 min, more preferably 0.5 to 15 g / 10 min, at a temperature of 230° C. and a load of 2.16 kg, according to ASTM D 1238. When the MFR is in the above range, the composition is excellent in moldability and sealability.

[0068] The density of the composition (Ia) measured in accordance with JIS K7112 is preferably 0.860 to 0.900 g / cm 3 , more preferably 0.865 to 0.890 g / cm 3 When the thickness is in the above range, the composition is excellent in flexibility and adhesiveness.

[0069] The content of the carbodiimide group in the composition (Ia) is preferably 0.1 to 50 mmol, more preferably 0.2 to 40 mmol, and even more preferably 0.5 to 30 mmol, per 100 g of the adhesive. When the content of the carbodiimide group in the composition (Ia) is within this range, the adhesiveness is excellent and crosslinking of the polyolefin (a) via the carbodiimide group-containing compound (b) can be suppressed, which is preferable.

[0070] The content of the carbodiimide group in the composition (Ia) can be calculated from the amount of the carbodiimide group-containing compound (b) added, and 13It can also be measured by C-NMR, IR, titration, etc., and can be understood as the carbodiimide group equivalent. 13 It is possible to observe peaks at 130 to 142 ppm in C-NMR and 2130 to 2140 cm-1 in IR. 13 The C-NMR measurement is carried out, for example, by the measurement method described in the above-mentioned method for measuring the carbodiimide group content in the carbodiimide group-containing compound (b).

[0071] Carbodiimide-modified polyolefin (D) is produced by reacting the carbodiimide group (NCN) of the carbodiimide group-containing compound (b) with a group that reacts with the carbodiimide group of the polyolefin (a) as described above, and a certain amount of carbodiimide groups are consumed during this reaction. The residue of the carbodiimide group that is connected to the polyolefin group as the same molecular chain contributes to adhesion to polyketones or polar resins, etc. If the content of the carbodiimide group in the composition (Ia) exceeds the above-mentioned range, there will be an excess of free carbodiimide groups in the composition (Ia) relative to the carbodiimide-modified polyolefin (D), and the adhesive performance and moldability will decrease.

[0072] The reaction rate between the polyolefin (a) and the carbodiimide group-containing compound (b) can be evaluated by the following method. After preparing heat-pressed sheets of the polyolefin (a) (reference) having a group reactive with the carbodiimide group and the composition (Ia), infrared absorption is measured using an infrared absorption analyzer. From the chart obtained, the difference between the absorbance derived from the group reactive with the carbodiimide group in the polyolefin (a), the absorbance derived from the group reactive with the carbodiimide group in the polyolefin (a) and the absorbance derived from the group reactive with the carbodiimide group in the adhesive can be compared to calculate the reaction rate using the following formula (α1). When a group derived from maleic anhydride is used as the group reactive with the carbodiimide group, the reaction rate at 1790 cm -1 Near-field absorbance can be used.

[0073] Reaction rate (%) = {P / Q} × 100... formula (α1) P: The difference between the absorbance due to the group reacting with the carbodiimide group in the polyolefin (a) and the absorbance due to the group reacting with the carbodiimide group in the adhesive Q: Absorbance derived from the group that reacts with the carbodiimide group in polyolefin (a) The reaction rate of the adhesive determined by the above method is usually in the range of 40 to 100%, preferably 60 to 100%, and more preferably 80 to 100%.

[0074] In addition, the carbodiimide group is converted to a urea group by absorbing water, but even the urea group exhibits high reactivity with polyketones or polar resins, etc. Therefore, the adhesive may contain polyolefins in which the carbodiimide group has been converted to a urea group by, for example, water in the air, and this is one of the preferred embodiments of the present invention.

[0075] Composition (Ia) can be prepared by various known methods, such as a method of dry blending the above components using a Henschel mixer, a tumbler blender, a V-blender, or the like, a method of dry blending and then melt kneading using a single-screw extruder, a multi-screw extruder, a Banbury mixer, or the like, and a method of stirring and mixing in the presence of a solvent.

[0076] The composition (Ia) may contain, as necessary, additives commonly used in the art, such as antioxidants, weather stabilizers, antistatic agents, antifogging agents, antiblocking agents, lubricants, nucleating agents, pigments, or other polymers, rubbers, etc., within the scope of the invention.

[0077] <Metal layer (II)> The metal constituting the metal layer (II) is not particularly limited, and examples thereof include aluminum, titanium, copper, nickel, and alloys containing at least one selected from these. For example, when the metal layer (II) is a lead substrate of a tab lead connected to the positive electrode of a lithium ion battery, the metal layer (II) is preferably made of aluminum, titanium, and an alloy containing at least one selected from these. When the metal layer (II) is a lead substrate of a tab lead connected to the negative electrode of a lithium ion battery, the metal layer (II) is preferably made of copper, nickel, and an alloy containing at least one selected from these.

[0078] The metal layer (II) is, for example, a metal sheet or a metal plate. One embodiment of the metal layer (II) is a lead substrate constituting a tab lead connected to an electrode selected from a positive electrode and a negative electrode of a lithium ion battery.

[0079] <Polyolefin resin layer (III)> The composite of the present invention may further include a polyolefin resin layer (III). The polyolefin resin layer (III) is formed, for example, on the surface of the composition layer (I) that is not in contact with the metal layer (II). That is, the composite of the present invention may have a structure of metal layer (II) / composition layer (I) / polyolefin resin layer (III).

[0080] Examples of the polyolefin resin in the polyolefin resin layer (III) include thermoplastic polyolefin resins such as polyethylene, polypropylene, and 4-methyl-1-pentene polymer. These may be used alone or in combination of two or more. The polyolefin resin may be crosslinked. As the polyolefin resin in the polyolefin resin layer (III), 4-methyl-1-pentene polymer is preferred from the viewpoint of heat resistance.

[0081] The 4-methyl-1-pentene polymer preferably contains 90 mol% to 100 mol% of structural units derived from 4-methyl-1-pentene, more preferably 92 mol% to 100 mol%, and even more preferably 95 mol% to 100 mol% of structural units derived from 4-methyl-1-pentene. The 4-methyl-1-pentene polymer preferably contains 0 mol% to 10 mol% of structural units derived from α-olefins having 2 to 20 carbon atoms other than 4-methyl-1-pentene, more preferably 0 mol% to 8 mol%, and even more preferably 0 mol% to 5 mol% of structural units derived from α-olefins having 2 to 20 carbon atoms other than 4-methyl-1-pentene. Examples of α-olefins having 2 to 20 carbon atoms other than 4-methyl-1-pentene include ethylene, propylene, 1-butene, 1-hexene, 1-octene, 1-decene, 1-tetradecene, and 1-octadecene.

[0082] The 4-methyl-1-pentene polymer preferably has a melting point Tm of 200°C or higher, more preferably 210 to 240°C, and further preferably 220 to 235°C, as measured by a differential scanning calorimeter (DSC).

[0083] <Other Layers (IV)> The composite of the present invention may further have another layer (IV). The other layer (IV) is formed, for example, on one of the two surfaces of the polyolefin resin layer (III) that is farther from the metal layer (II). That is, the composite of the present invention may have a structure of metal layer (II) / composition layer (I) / polyolefin resin layer (III) / other layer (IV).

[0084] The other layer (IV) is preferably a layer formed from the above-mentioned composition (Ia). When the other layer (IV) is a layer formed from the composition (Ia), it is preferable that a polyolefin resin layer, particularly a polypropylene resin layer, is further formed on the surface of the other layer (IV) in terms of excellent adhesive strength. The other layer (IV) may be a layer having the same composition as the composition layer (I), or may be a layer having a different composition.

[0085] In another embodiment, the other layer (IV) contains at least one resin selected from known acid-modified polyolefin resins and crosslinked products thereof. Examples of the acid-modified polyolefin resin include acid-modified thermoplastic polyolefin resins such as acid-modified polyethylene and acid-modified polypropylene. These may be used alone or in combination. The use of acid-modified polypropylene is preferred from the viewpoint of heat resistance.

[0086] <Complex Structure> The composition of the complex of the present invention is, for example, metal layer (II) / composition layer (I), Metal layer (II) / composition layer (I) / polyolefin resin layer (III), Metal layer (II) / composition layer (I) / polyolefin resin layer (III) / other layer (IV), composition layer (I) / metal layer (II) / composition layer (I), Polyolefin resin layer (III) / composition layer (I) / metal layer (II) / composition layer (I) / polyolefin resin layer (III), Other layer (IV) / polyolefin resin layer (III) / composition layer (I) / metal layer (II) / composition layer (I) / polyolefin resin layer (III) / other layer (IV) Metal layer (II) / composition layer (I) (layer formed from composition (Ia)) / polyolefin resin layer (III) / composition layer (I) (layer formed from composition (Ia)) Examples include:

[0087] In the composite of the present invention, the composition layer (I) is not necessarily formed on the entire surface of the metal layer (II), but the composition layer (I) may be formed on a part of the metal layer (II). For example, in the case of a tab lead for a lithium ion battery described later, the composition layer (I) is preferably formed so as to cover the metal layer (II) (corresponding to the lead substrate) at a portion sealed with an exterior member.

[0088] <Thickness of each layer of the composite and manufacturing method of the composite> The complex of the present invention can be produced, for example, by the following method. When the composition layer (I) is used alone, a film or sheet is formed from the composition (Ia) using a molding machine such as a T-die extrusion molding machine or an inflation molding machine. The molding temperature is, for example, 180 to 250°C. Next, the film or sheet corresponding to the composition layer (I) and a metal member corresponding to the metal layer (II) are bonded together and heat-sealed, specifically, thermocompression-bonded. At this time, the thickness of the composition layer (I) is usually 5 to 300 μm, preferably 10 to 250 μm.

[0089] When the polyolefin resin layer (III) and, if necessary, another layer (IV) are provided, films corresponding to the above (I), the above (III), and, if necessary, the above (IV) are molded in advance, and then subjected to thermocompression bonding or the like to produce a laminated film. Alternatively, the composition layer (I), the polyolefin resin layer (III), and, if necessary, the other layer (IV) may be molded by a known multilayer molding method to produce a laminated film. Examples of known multilayer molding methods include coextrusion molding and extrusion lamination. In this case, the total thickness of the composition layer (I), the polyolefin resin layer (III), and, if necessary, the other layer (IV) is usually 10 to 300 μm, preferably 10 to 250 μm. Among these, the thickness of the composition layer (I) is usually 3 to 50 μm, preferably 5 to 40 μm, the thickness of the polyolefin resin layer (III) is, for example, 7 to 297 μm or 5 to 245 μm, and the thickness of the other layer (IV) is usually 3 to 50 μm, preferably 5 to 40 μm. Next, the laminated film and a metal member corresponding to the metal layer (II) are attached to each other so that the composition layer (I) is in contact with the metal layer (II), and are thermally fused, specifically, thermally compressed.

[0090] The thickness of the metal layer (II) is not particularly limited and may be appropriately selected depending on the desired application, but is preferably 2 μm to 100 mm, more preferably 5 μm to 50 mm. The conditions for heat fusion, specifically the conditions for thermocompression, are, for example, usually 130 to 200° C., preferably 140 to 180° C., and usually 0.1 to 1 MPa, preferably 0.2 to 0.8 MPa.

[0091] Among these, it is particularly preferable to use the composite of the present invention as a tab lead. The lead is a terminal that transfers electricity between the electrode in the battery and the outside. The body is a tably for lithium ion batteries, especially for laminated lithium ion batteries. The laminated lithium ion battery is preferably used as a lithium ion battery. As a battery, it is lightweight, has a high degree of freedom in shape, and allows for fast charging.

[0092] The tab lead of the present invention has a metal layer (II) which is a lead substrate, and a tab lead film formed on at least one side of the lead substrate. The tab lead may have tab lead films on both sides of the lead substrate.

[0093] The tab lead film has a composition layer (I) in contact with the lead substrate, and in one embodiment, a polyolefin resin layer (III) and, if necessary, another layer (IV) may be further provided on the composition layer (I). The tab lead film is formed to cover a part of the lead substrate (lead conductor) and to be bonded to the inner surface of an exterior member of a lithium ion battery described later. As an example, FIG. 1 shows a configuration in which the lead substrate and the exterior member are bonded by the tab lead film.

[0094] In one embodiment, the tab lead film is a laminated film having a heat-resistant layer and an adhesive layer. In a lithium ion battery, the adhesive layer is adhered to a lead substrate, and the heat-resistant layer is adhered to an inner surface of an exterior member. In one embodiment, the metal layer (II) in the composite of the present invention corresponds to the lead substrate, the composition layer (I) corresponds to the adhesive layer of the tab lead film, and the polyolefin resin layer (III) corresponds to the heat-resistant layer of the tab lead film.

[0095] Examples of materials constituting the lead substrate include aluminum, titanium, copper, nickel, and alloys containing at least one selected from these. For example, a lead conductor made of aluminum, titanium, and alloys containing at least one selected from these is used as the lead substrate connected to the positive electrode of the lithium ion battery, and for example, a lead conductor made of copper, nickel, and alloys containing at least one selected from these is used as the lead substrate connected to the negative electrode of the lithium ion battery.

[0096] [Lithium-ion battery] The lithium ion battery of the present invention has the above-mentioned tab lead. Specifically, the lithium ion battery of the present invention has a positive electrode, a negative electrode, a separator between the positive electrode and the negative electrode, an electrolyte, and an exterior member that contains (i.e., encapsulates) these. The lithium ion battery has a positive electrode tab lead electrically connected to the positive electrode, and a negative electrode tab lead electrically connected to the negative electrode.

[0097] The positive electrode, the negative electrode, and the separator may have a conventionally known configuration. The positive electrode and the negative electrode each have, for example, a metal substrate called a current collector, and an active material layer on the metal substrate. For the metal substrate of the positive electrode, for example, an electrode conductor made of aluminum, titanium, and an alloy containing at least one selected from these is used. For the metal substrate of the negative electrode, for example, an electrode conductor made of copper, nickel, and an alloy containing at least one selected from these is used. The separator is formed, for example, of a polyolefin-based porous film. The electrodes in the lithium ion battery may be a laminated electrode group in which a positive electrode and a negative electrode are laminated with a separator interposed therebetween.

[0098] The electrolyte may be a non-aqueous electrolyte in which an electrolyte is dissolved in an organic solvent. The electrolyte may be, for example, a lithium compound such as LiClO4, LiBF4, LiPF6, or LiAsF6. The organic solvent may be, for example, propylene carbonate, ethylene carbonate, diethyl carbonate, dimethyl carbonate, 1,2-dimethoxyethane, or tetrahydrofuran.

[0099] In order to extract a current from the lithium ion battery to the outside, i.e., to enable electrical connection to the outside, the positive electrode tab lead and the negative electrode tab lead extend from inside the exterior member to the outside. Specifically, the metal substrate of the positive electrode is electrically connected to one end of the positive electrode tab lead, and the other end of the positive electrode tab lead extends to the outside of the exterior member. In addition, the metal substrate of the negative electrode is electrically connected to one end of the negative electrode tab lead, and the other end of the negative electrode tab lead extends to the outside of the exterior member.

[0100] In the lithium ion battery of the present invention, the tab lead of the present invention is used for at least one tab lead. At the portion where the tab lead is taken out from the exterior member, a part of the lead substrate and the exterior member are joined by heat fusion of the tab lead film. Although the sealing property of the exterior member may decrease at the tab lead take-out portion, in the present invention, the heat fusion can prevent the sealing property of the exterior member from decreasing. Also, in the present invention, the adhesive strength of the seal is high and excellent.

[0101] The exterior member is usually a bag-shaped member made of a laminate sheet having a metal layer, that is, a laminate packaging material. The laminate sheet has a metal layer made of a metal such as aluminum, copper, or stainless steel, and a resin film formed on both sides of the metal layer. By adopting such a configuration, the sealing property of the exterior member is improved.

[0102] The innermost film of the exterior member (the resin film on the inside of the battery) is made of, for example, polypropylene having excellent heat sealability in order to prevent the nonaqueous electrolyte from leaking from the sealed portion since it comes into contact with the nonaqueous electrolyte. The outermost film of the exterior member (the resin film on the outside of the battery) is made of, for example, polyester such as polyethylene terephthalate in order to protect the metal layer from external damage.

[0103] The exterior member can be formed by heat-sealing the peripheral seal parts of two laminate sheets cut into a rectangular shape. For example, three sides of the rectangular peripheral parts of the two laminate sheets are heat-sealed to a desired seal width. In this way, an exterior member having an opening with three sealed sides and one open side is obtained.

[0104] Next, the components of the lithium ion battery and a part of the tab lead are housed inside an exterior member having an opening through the opening. Next, the part of the tab lead where the tab lead film is formed is sandwiched between the exterior members at the opening end and heat sealed. In this manner, the lithium ion battery of the present invention can be obtained. EXAMPLES

[0105] (Various measurement methods) In the present examples, measurements were carried out according to the following method.

[0106] [Melt flow rate (MFR) of adhesive resin composition] The melt flow rate of the adhesive resin composition was measured under the following conditions in accordance with ASTM D1238. Polyethylene polymer: 190℃, 2.16kg load Polypropylene polymer: 230℃, under a load of 2.16 kg 4-Methyl-1-pentene polymer: 260°C, under a load of 5 kg.

[0107] [density] The density was measured in accordance with JIS K7112.

[0108] [Number average molecular weight of carbodiimide group-containing compound] The number average molecular weight was measured by gel permeation chromatography (GPC) using tetrahydrofuran as the solvent (mobile phase) at a column temperature of 40°C (polystyrene equivalent, Mw: weight average molecular weight, Mn: number average molecular weight). Standard polystyrene has a molecular weight of 580≦Mw≦7×10 6 For this, polystyrene PS-1 manufactured by Agilent Technologies Inc. (formerly Polymer Laboratories Limited) was used.

[0109] [Carbodiimide group content] The carbodiimide group content in the examples and comparative examples was calculated from the charged amount of the carbodiimide group-containing compound.

[0110] [Maleic anhydride grafting amount] The graft amount of maleic anhydride was measured by FT-IR as follows: A sample was heat-pressed at 250° C. for 3 minutes to prepare a sheet, and then an infrared spectrophotometer (FT-IR410, manufactured by JASCO Corporation) was used to measure the graft amount at 1790 cm -1 The infrared absorption spectrum was measured at a resolution of 2 cm. -1 The number of integration times was set to 32.

[0111] The polyolefins used in the examples and comparative examples are shown below. The propylene polymer (A), ethylene polymer (B) and thermoplastic resin (C) were all prepared by polymerization according to a conventional method.

[0112] Propylene polymer (A) PP-1: Random polypropylene (Melt flow rate (230℃, 2.16 kg load): 7.0g / 10min, density: 0.900g / cm 3 , propylene content: 95 mol%, ethylene content: 5 mol%) PP-2: Maleic anhydride modified homopolypropylene (Melt flow rate (230℃, 2.16 kg load): 100g / 10min, density: 0.900g / cm 3 Maleic anhydride graft amount: 3.0% by mass PP-3: Polypropylene (Melt flow rate (230℃, 2.16 kg load): 5g / 10min, density: 0.900g / cm 3 , propylene content: 96 mol%, ethylene content: 4 mol%)

[0113] Ethylene polymer (B) PE-1: Polyethylene polymer (Melt flow rate (190℃, 2.16 kg load): 0.8g / 10min, density: 0.870g / cm 3 , propylene content: 19 mol%)

[0114] Thermoplastic resin (C) PMP-1: Propylene-4-methyl-1-pentene copolymer (MFR: 10g / 10min (230°C, 2.16kg load), density: 0.838g / cm 3 , propylene content: 15 mol%, 4-methyl-1-pentene content: 85 mol%, melting point measured by DSC: 130°C) PMP-2: Propylene-4-methyl-1-pentene copolymer (MFR: 10g / 10min (230°C, 2.16kg load), density: 0.840g / cm 3 , propylene content: 28 mol%, 4-methyl-1-pentene content: 72 mol%, no melting point observed by DSC)

[0115] Carbodiimide modified polyolefin (D) CDI-PP1: Carbodiimide-modified polyolefin obtained by Production Example 1 below

[0116] [Production Example 1] <Production of polyolefin (a) having a group reactive with a carbodiimide group> 100 parts of PP-1 was mixed with 1 part of maleic anhydride (manufactured by Wako Pure Chemical Industries, Ltd., hereinafter abbreviated as MAH) and 0.25 parts of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexyne-3 (manufactured by NOF Corp., trade name Perhexyne (registered trademark) 25B), and extruded using a twin-screw kneader at a cylinder temperature of 220°C, a screw rotation speed of 200 rpm, and a discharge rate of 80 g / min to obtain a maleic anhydride-modified polypropylene (hereinafter abbreviated as MAH-PP-1), which is polyolefin (a). The density of MAH-PP-1 was 0.905 g / cm 3 It was.

[0117] The obtained MAH-PP-1 was dissolved in xylene, and then the obtained xylene solution was poured into acetone to reprecipitate and purify MAH-PP-1. The graft amount of maleic anhydride was measured by FT-IR and was found to be 0.7 wt%.

[0118] <Production of Carbodiimide-Modified Polyolefin (D)> 100 parts of the MAH-PP-1 produced above and 8.8 parts of a carbodiimide group-containing compound (manufactured by Nisshinbo Chemical Inc., product name Carbodilite (registered trademark) HMV-15CA, carbodiimide group equivalent: 262, number average molecular weight: 3050, number of carbodiimide groups in one molecule: 12) were mixed and extruded using a twin-screw kneader at a cylinder temperature of 250°C, a screw rotation speed of 200 rpm, and a discharge rate of 80 g / min to produce pellets of carbodiimide-modified PP (hereinafter abbreviated as CDI-PP1), which is a carbodiimide-modified polyolefin (D).

[0119] The obtained CDI-PP1 had a MFR (230°C, 2.16 kg load) of 130 g / 10 min and a density of 0.905 g / cm 3 The carbodiimide group content calculated from the amount of the carbodiimide group-containing compound was 31 mmol / 100 g. According to the FT-IR analysis, CDI-PP1 showed a maleic anhydride peak (1790 cm -1) had disappeared, the ratio of the difference (P) between the absorbance attributable to groups in polyolefin (a) that react with carbodiimide groups and the absorbance attributable to groups in CDI-PP1 that react with carbodiimide groups to the absorbance (Q) attributable to groups in polyolefin (a) that react with carbodiimide groups was 1, and therefore the reaction rate was 100%.

[0120] Example 1 <Production of Resin Composition> 65 parts of the above PP-1, 5 parts of PP-2, and 30 parts of PMP-2 were mixed and melt-kneaded at 230°C using a twin-screw kneader (TEX-30, manufactured by Japan Steel Works, Ltd.) to obtain composition Ia- 1. The melt flow rate of the resulting composition was 8.3 g / 10 min and the density was 0.880 g / cm 3 It was.

[0121] <Production of Laminate> Compositions Ia-1 and MP-1 (poly 4-methyl-1-pentene (MFR: 26 g / 10 minutes (260℃, 5kg load), density: 0.833g / cm 3 %, 4-methyl-1-pentene content: 100 mol %, melting point measured by DSC: 220° C.) were coextruded under the following conditions to form a three-layer laminate.

[0122] Composition I was co-extruded using a T die-cast sheet molding machine (manufactured by EDI). A laminate of a-1 / MP-1 / composition Ia-1 was prepared. The extruder for the composition Ia-1 layer was The temperature was set to 230° C., the extruder temperature for the MP-1 layer was set to 275° C., the die temperature was set to 275° C., and the extruder was taken up at a speed of 4 m / min while being cooled by a chill roll. The thicknesses of the layers were composition Ia-1 / MP-1 / composition Ia-1=30 / 30 / 30 μm.

[0123] The interlayer adhesion strength of the laminate was evaluated by the following method. The results are shown in Table 1. Composition I When the a-1 layer and the MP-1 layer did not peel off, it was recorded as "not peeled off."

[0124] <Evaluation of interlayer adhesion of laminates> The obtained laminate was cut into a width of 15 mm, and the interface between the composition Ia-1 layer and the MP-1 layer was measured by the T-peel method using a tensile tester (IM-20ST type manufactured by Intesco Co., Ltd.). The interlayer adhesive strength (MP-1 interlayer adhesive strength) was measured at room temperature of 23°C. The crosshead speed was 300 mm / min. The unit of interlayer adhesion is N / 15mm.

[0125] <Production of the Complex> The three-layer laminate obtained above was sandwiched between an aluminum sheet having a thickness of 350 μm and a width of 15 mm and a PP film having a thickness of 100 μm and a width of 15 mm, and heat-sealed for 4 seconds using a heat sealer under conditions of 140°C and 0.2 MPa to produce a PP film / three-layer laminate / aluminum sheet composite. The interlayer adhesive strength of the composite was evaluated by the following method, and the results are shown in Table 1.

[0126] <Evaluation of interlayer adhesion of composites> The interlayer adhesive strength (aluminum interlayer adhesive strength) at the interface between the aluminum sheet of the obtained composite and the three-layer laminate was measured at room temperature of 23°C. The crosshead speed was 200 mm / min. The unit of interlayer adhesion is N / 15mm.

[0127] The interlayer adhesive strength (PP interlayer adhesive strength) at the interface between the PP film of the obtained composite and the three-layer laminate was measured at room temperature of 23°C. The crosshead speed was 200 mm / min. The unit of interlayer adhesion is N / 15mm.

[0128] [Examples 2 to 5, Comparative Examples 1 to 2] Resin compositions, laminates, and composites were produced in the same manner as in Example 1 according to the formulations shown in Table 1. The melt flow rates and densities of the resulting compositions, and the interlayer adhesive strengths of the laminates and composites were measured in the same manner as in Example 1. The results are shown in Table 1.

[0129] Example 6 <Production of Composition> CDI-PP1 20 copies, PP-3 45 Division, PE-1 10 Division, and PMP-2 25 The mixture was mixed and extruded using a twin-screw extruder at a cylinder temperature of 250° C., a screw rotation speed of 200 rpm, and a discharge rate of 80 g / min to obtain composition Ia-6. No. The lubricant flow rates and densities are shown in Table 1.

[0130] <Production of Laminate> The layers of compositions Ia-6 and MP-1 were coextruded under the following conditions to obtain a three-layer laminate: was molded.

[0131] Composition I was co-extruded using a T die-cast sheet molding machine (manufactured by EDI). A laminate of Ia-6 / MP-1 / composition Ia-6 was prepared. The extruder for the composition Ia-6 layer was The temperature was set to 270° C., the extruder temperature for the MP-1 layer was set to 275° C., the die temperature was set to 275° C., and the extruder was taken up at a speed of 4 m / min while being cooled by a chill roll. The thicknesses of the layers were composition Ia-6 / MP-1 / composition Ia-6=30 / 30 / 30 μm.

[0132] <Evaluation of interlayer adhesion of laminates> The interlayer adhesive strength of MP-1 in the resulting laminate was measured in the same manner as in Example 1. The results are shown in Table 1.

[0133] <Production of the Complex> The three-layer laminate obtained above was sandwiched between an aluminum sheet having a thickness of 350 μm and a width of 15 mm and a PP film having a thickness of 100 μm and a width of 15 mm, and heat-sealed for 4 seconds using a heat sealer at 250° C. and 0.2 MPa.

[0134] <Evaluation of interlayer adhesion of composites> The adhesive strength between the aluminum layers and the adhesive strength between the PP layers of the obtained composite were measured in the same manner as in Example 1. The results are shown in Table 1.

[0135] Example 7 Compositions, laminates and composites were produced in the same manner as in Example 6 according to the formulations shown in Table 1. The melt flow rates and densities of the resulting compositions, and the interlayer adhesive strengths of the laminates and composites were measured in the same manner as in Example 1. The results are shown in Table 1.

[0136] [Table 1] [Explanation of symbols]

[0137] 10...Lead substrate (metal layer (II)) 20...Tab lead film 21...Composition layer (I) 22...Polyolefin resin layer (III) 23...Other layers (IV) 30…Exterior material

Claims

1. A composition layer (I) formed from a composition (Ia); a metal layer (II) in contact with the composition layer (I); a polyolefin resin layer (III) formed on a surface of the composition layer (I) that is not in contact with the metal layer (II); is a complex having The composition (Ia) comprises the content ratio of the propylene-based polymer (A) containing 75 to 100 mol % of structural units derived from propylene is 45 to 75 parts by mass, The content of the ethylene polymer (B) is 0 to 20 parts by mass, The resin composition contains a copolymer having 60 mol% or more and 99 mol% or less of structural units derived from 4-methyl-1-pentene and 1 mol% or more and 40 mol% or less of structural units derived from an α-olefin having from 2 to 20 carbon atoms other than 4-methyl-1-pentene, and the structural units derived from the 4-methyl-1-pentene and the structural units derived from the α-olefin having from 2 to 20 carbon atoms other than 4-methyl-1-pentene are 100 mol% in total, and the content of a thermoplastic resin (C) having a melting point Tm of 199°C or less or substantially no melting point Tm measured by a differential scanning calorimeter (DSC) is 15 to 45 parts by mass (wherein the total of the (A), (B) and (C) is taken as 100 parts by mass). Complex.

2. 2. The composite according to claim 1, wherein a part or all of the polymers contained in the propylene-based polymer (A), the ethylene-based polymer (B) and the thermoplastic resin (C) are graft-modified with an unsaturated carboxylic acid and / or a derivative thereof.

3. 3. The composite according to claim 1 or 2, further comprising the composition layer (I) formed on a surface of the polyolefin resin layer (III) that is not in contact with the composition layer (I).

4. The polyolefin resin layer (III) contains a polymer in which the content ratio of structural units derived from 4-methyl-1-pentene to all structural units is 90 mol% or more and 100 mol% or less, and the content ratio of structural units derived from α-olefins other than 4-methyl-1-pentene to all structural units is 0 mol% or more and 10 mol% or less, and the melting point Tm measured by differential scanning calorimetry (DSC) is 200 ° C. or more. The composite according to any one of claims 1 to 3.

5. The composition (Ia) further contains a carbodiimide-modified polyolefin (D), and in the composition (Ia), the content ratio of (A) is 45 to 65 parts by mass, the content ratio of (B) is 0 to 20 parts by mass, the content ratio of (C) is 15 to 45 parts by mass, and the content ratio of (D) is 5 to 30 parts by mass, per 100 parts by mass of the total of (A), (B), (C), and (D). The composite according to any one of claims 1 to 4.

6. A tab lead for a lithium ion battery comprising the composite according to any one of claims 1 to 5.

7. A lithium ion battery having the tab lead according to claim 6.

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