TW201807133A - Adhesive composition for laminate, laminate and secondary battery - Google Patents

Abstract

An adhesive composition for laminating which comprises a modified polyolefin resin (A) having a melting point of 90 DEG C or lower, a modified polyolefin resin (B) having a melting point that is higher than that of the modified polyolefin resin (A) and is not higher than 140 DEG C, and a hardener (C), wherein the proportion of the modified polyolefin resin (B) to the sum, on a solid basis, of the modified polyolefin resin (A) and the modified polyolefin resin (B) is 0.1-20 mass%; a laminate in which the adhesive composition for laminating was used as an adhesive for a metal layer and a polyolefin resin layer; and a secondary battery which includes the laminate as an electrolytic-solution-enclosing film or an electrode-part-protecting film.

Description

Adhesive composition for laminate, laminate, and secondary battery

The present invention relates to a laminate adhesive composition, a laminate, and a secondary battery.

A secondary battery typified by a lithium-ion battery has a configuration in which an electrolyte, etc. are sealed between a positive electrode, a negative electrode, and the like. In addition, as a sealing bag for encapsulating the "lead for taking out electricity from the positive electrode and the negative electrode to the outside", a laminated body obtained by bonding a metal foil such as aluminum foil or a metal vapor-deposited layer with plastic is used.

For this laminated system, the moisture resistance, heat resistance, solvent resistance, and durability required as secondary batteries are required. In particular, it is difficult to obtain electrolyte resistance that is insoluble in electrolytes by low-temperature curing, and it has become a technology to be solved. Topic.

For example, Patent Document 1 proposes a method in which a heat-sealed portion is formed by using a maleic acid-modified polyolefin resin in the innermost layer of a laminate, and constituting a heat-sealing portion with the same maleic acid-modified polyolefin resin. Sealed in a sealed bag. Maleic acid modified polyolefin resins are generally used as adhesive resins due to their excellent adhesion to metals and heat sealability. but If it is used as a sealing film for a battery as described above, although it shows excellent adhesion immediately after lamination at a high temperature, the electrolyte resistance is low, and interlayer peeling occurs over time, and it cannot be used as a sealing film.

Patent Document 2 describes a laminate for a battery electrolyte sealing film or a laminate for a battery electrode portion protection film, which comprises a metal layer, a surface treatment layer formed on a surface of the metal layer, and a substrate formed on the surface treatment layer. Adhesive resin layer made of polyolefin modified with carboxylic acid group or its derivative.

Patent Document 3 describes an adhesive resin composition comprising: (A) a polyolefin-based resin having at least one functional group selected from the group consisting of an acid anhydride group, a carboxyl group, and a carboxylic acid metal salt; and (B) ) An epoxidized vegetable oil having two or more epoxy groups and a molecular weight of 3,000 or less, wherein the blending amount of the (B) component is 0.01 to 5 parts by mass relative to 100 parts by mass of the component (A).

Patent Document 4 describes a resin composition for a binder for a secondary battery electrode, which is characterized by containing an acid-modified polyolefin resin (A) and a polyurethane resin (B), in which 100 parts by mass of ( A) and (B) are 0.5 to 100 parts by mass.

In the past, many patents have been applied for the use of an acid group-containing polyolefin resin as an adhesive for secondary battery laminates.

However, only a polyolefin resin containing only acid groups is used, and although the adhesion to the olefin sheet is excellent due to the steps such as high-temperature aging and extrusion lamination, the adhesion to the metal layer is insufficient. As a result, the adhesive strength as an adhesive for laminated bodies was insufficient. Further, when used in a secondary battery, the electrolyte resistance is not sufficient, and interlayer peeling may occur over time. And so on.

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 9-283101

[Patent Document 2] WO2001 / 017043

[Patent Document 3] Japanese Patent Laid-Open No. 08-193148

[Patent Document 4] Japanese Patent Laid-Open No. 2010-277959

An object of the present invention is to provide an adhesive composition for a laminated laminate, a method for producing the same, a laminate using "adhesive using the adhesive composition", and a secondary battery, the adhesive composition and the laminate The metal layer and the plastic layer are excellent in adhesion, and have electrolyte resistance even at low temperature curing. The retention rate is high, and interlayer peeling does not occur over time.

It is also a problem to provide an adhesive composition having excellent solution stability.

As a result of research conducted by the present inventors, the above-mentioned problems are solved by a laminating adhesive composition containing a modified polyolefin resin (A) having a melting point of 90 ° C. or lower and a melting point ratio modified. Modified polyolefin resin (A) is higher and modified polyolefin resin (B) and hardener (C) below 140 ° C. Among them, modified polyolefin resin (A) and modified polyolefin resin (B) The total mass of solid content, modified polyolefin tree The fat (B) is 0.1 to 20% by mass.

That is, the present invention provides an adhesive composition for lamination, which contains a modified polyolefin resin (A) having a melting point of 90 ° C. or lower, and a modified melting point higher than that of the modified polyolefin resin (A) and 140 ° C. or lower. The polyolefin resin (B) and the hardener (C), wherein the modified polyolefin resin (A) and the modified polyolefin resin (B) have a total mass of the solid content of the modified polyolefin resin (A) B) is 0.1 to 20% by mass.

In addition, the present invention provides a laminate comprising a metal layer and a polyolefin resin layer, wherein the laminate adhesive composition according to any one of claims 1 to 7 is used as the metal layer and the polyolefin resin layer. The adhesive.

The present invention also provides a secondary battery using the above-mentioned laminated body as an electrolytic solution sealing film or an electrode portion protective film.

According to the present invention, it is possible to provide an adhesive composition for a laminated laminate, a method for producing the same, a laminated body using the "adhesive using the adhesive composition", and a secondary battery, and an adhesive for the laminated laminate. The composition has excellent adhesion to the metal and plastic layers of the laminate, and has both electrolyte resistance even at low temperature curing. Its retention is high, and interlayer peeling does not occur over time. The adhesive composition has the characteristics of excellent solution stability.

[Form of Implementing Invention]

The present invention is composed of the following items.

An adhesive composition for lamination comprising a modified polyolefin resin (A) having a melting point of 90 ° C. or lower, and a modified polyolefin resin having a higher melting point than the modified polyolefin resin (A) and 140 ° C. or lower (B) and hardener (C), wherein the modified polyolefin resin (B) is based on the total mass of the solid content of the modified polyolefin resin (A) and the modified polyolefin resin (B), 0.1 to 20% by mass.

2. The adhesive composition for lamination according to 1., wherein the difference in melting point between the modified polyolefin resin (A) and the modified polyolefin resin (B) is 5 ° C to 80 ° C.

3. The adhesive composition for lamination according to 1. or 2., wherein the modified polyolefin resin (A) and the modified polyolefin resin (B) have an acid value of 1 to 200 mgKOH / g, and / or The hydroxyl value is 1 to 200 mgKOH / g, and the melting point is 60 ° C to 140 ° C.

4. The laminating adhesive composition according to any one of 1. to 3., wherein the hardener (C) is selected from the group consisting of an epoxy compound, a polyisocyanate, and a carbodiimide , Oxazolines, and amine-based resins.

5. The adhesive composition for lamination according to 4., wherein the epoxy compound has two or more epoxy groups in one molecule and one or more hydroxyl groups in one molecule, and the weight average molecular weight is 3000 the following.

6. The adhesive composition for lamination according to any one of 1. to 5., based on the total mass of the solid content of the modified polyolefin resin (A) and the modified polyolefin resin (B), The mass% of the hardener (C) (mass of the hardener (C) / (mass of the modified polyolefin resin (A) + mass of the modified polyolefin resin (B))) is 0.5 to 5 (mass%) Within range.

7. The laminating adhesive composition according to any one of 1. to 6., further comprising a thermoplastic elastomer, a tackifier, a catalyst, a phosphoric acid compound, a reactive elastomer, or a silane coupling agent.

A laminated body comprising a metal layer and a polyolefin resin layer, wherein the laminate adhesive composition according to any one of 1. to 7. is used as a bonding between the metal layer and the polyolefin resin layer. Agent.

9. A secondary battery using the laminated body as described in 8. as an electrolytic solution sealing film or an electrode part protection film.

(Modified polyolefin resins (A) and (B))

As the modified polyolefin resin (A) of the present invention, a well-known and commonly used modified polyolefin resin having a melting point of 90 ° C. or lower can be used.

In addition, as the modified polyolefin resin (B) of the present invention, a well-known and commonly used modified polyolefin resin having a higher melting point than the modified polyolefin resin (A) and 140 ° C or lower can be used. The melting points of the two are not limited as long as they are different, and the difference is particularly preferably 5 ° C to 80 ° C.

Examples of the polyolefin resins (A) and (B) of the present invention include copolymers of olefins having 2 to 8 carbons, and copolymers of olefins having 2 to 8 carbons and other monomers.

Specific examples include polyethylene such as high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene resin, polypropylene, polyisobutylene, and poly (1-butene). , Poly4-methylpentene, polyvinylcyclohexane, polystyrene, poly (p-methylstyrene), poly (α-methylstyrene), ethylene · propylene block copolymer, ethylene · propylene Random copolymers, ethylene‧butene-1 copolymers, ethylene‧4-methyl-1-pentene copolymers, α-olefin copolymers such as ethylene‧hexene copolymers, ethylene‧ethyl acetate Ester copolymer, ethylene‧acrylic copolymer, ethylene‧methyl methacrylate copolymer, ethylene‧vinyl acetate‧methyl methacrylate copolymer, ionic polymer resin, etc. Furthermore, a chlorinated polyolefin obtained by chlorinating these polyolefins may be used.

Examples of the polyolefin resins (A) and (B) of the present invention include modified polyolefin resins (A) and modified polyolefin resins (B) having an acid value of 1 to 200 mgKOH / g, and / or hydroxyl groups. The value is 1 to 200 mgKOH / g, and the melting point is 60 ° C to 140 ° C.

Various polyolefin resins (A) and (B) used in the present invention can be used. In particular, modified polyolefin resins having various functional groups (for example, carboxyl group, hydroxyl group, etc.) introduced into the polyolefin resin can be used. Among these modified polyolefin resins, modified polyolefin resins having an acid value of 1 to 200 mgKOH / g (described below) are more preferred in terms of further improving the adhesion of the metal layer and excellent electrolyte resistance. Is an acid-modified polyolefin resin) and / or a modified polyolefin resin (hereinafter referred to as a hydroxy-modified polyolefin resin) having a hydroxyl value of 1 to 200 mgKOH / g.

The acid-modified polyolefin resin is a polyolefin resin having a carboxyl group or a carboxylic anhydride group in the molecule, and is synthesized by modifying a polyolefin with an unsaturated carboxylic acid or a derivative thereof. As this modification method, graft modification and copolymerization can be used.

The acid-modified polyolefin resin is a graft-modified polyolefin obtained by graft-modifying or copolymerizing at least one polymerizable ethylenically unsaturated carboxylic acid or a derivative thereof. . Examples of the polyolefin resin before modification include the above-mentioned polyolefin resins. Among them, homopolymers of propylene and copolymers of propylene and α-olefin are particularly preferred. These can be separated One type may be used, or two or more types may be used in combination.

Examples of the ethylenically unsaturated carboxylic acid or a derivative thereof subjected to graft modification or copolymerization of the polyolefin resin before the modification include acrylic acid, methacrylic acid, maleic acid, itaconic acid, Citraconic acid, mesaconic acid, maleic anhydride, 4-methylcyclohex-4-ene-1,2-dicarboxylic anhydride, bicyclo [2.2.2] oct-5-ene-2,3-di Formic anhydride, 1,2,3,4,5,8,9,10-octahydronaphthalene-2,3-dicarboxylic anhydride, 2-octane-1,3-dionespiro [4.4] non-7-ene , Bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylic anhydride, maleopimaric acid, tetrahydrophthalic anhydride, methyl-bicyclo [2.2.1] hept-5-ene- 2,3-dicarboxylic anhydride, methyl-norborn-5-ene-2,3-dicarboxylic anhydride, norborn-5-ene-2,3-dicarboxylic anhydride, and the like. Preferably, maleic anhydride is used. These may be used alone or in combination of two or more.

Various methods can be used for grafting a graft monomer selected from an ethylenically unsaturated carboxylic acid or a derivative thereof to a polyolefin resin before modification. For example, a method of melting a polyolefin resin, adding a graft monomer to the graft reaction, and dissolving the polyolefin resin in a solvent to prepare a solution, and adding the graft monomer to the graft resin to perform the graft reaction. Method for branch reaction; mixing a polyolefin resin dissolved in an organic solvent with the aforementioned unsaturated carboxylic acid, etc., heating at the softening temperature of the above-mentioned polyolefin resin or a temperature above the melting point, and simultaneously performing radical polymerization in a molten state and Methods of hydrogen abstraction reaction. In any case, in order to efficiently perform graft copolymerization of the above-mentioned graft monomers, it is preferable to perform the graft reaction in the presence of a radical initiator. The grafting reaction is usually carried out at 60 to 350 ° C. The ratio of the radical initiator to 100 parts by mass of the polyolefin resin before the modification , Usually in the range of 0.001 to 1 part by mass.

As the adhesive of the present invention, a radical initiator can be used. As a preferable initiator, an imidazole radical initiator can be mentioned, but it is not limited thereto.

Examples include triphenylphosphine, 1,8-diazinebicyclo (5.4.0) undecene-7 (DBU) -phenate, DBU-octanoate, and the like.

Examples of these acid-modified polyolefin resins include maleic anhydride-modified polypropylene, ethylene- (meth) acrylic acid copolymer, ethylene-acrylic acid ester-maleic anhydride terpolymer, or Ethylene-methacrylate-maleic anhydride terpolymer. Specifically, "Modic" made by Mitsubishi Chemical Corporation, "ADMER" made by Mitsui Chemicals Corporation, "UNISTOLE", "TOYO-TAC" made by Toyobo Corporation, and "Youmex" made by Sanyo Chemical Co., Ltd. are commercially available. "," REXPEARL EAA "" REXPEARL ET "made by Japan Polyethylene (stock)," PRIMACOR "made by Dow Chemical (stock)," Nucrel "made by Du Pont-Mitsui Polychemicals, and" BONDINE "made by Arkema.

The hydroxy modified polyolefin resin is a polyolefin resin having a hydroxyl group in the molecule, which is obtained by graft-modifying or copolymerizing a hydroxyl group-containing (meth) acrylate or a hydroxyl ether-containing vinyl ether, which will be described later in the polyolefin. synthesis. The polyolefin resin before the modification and the modification method are the same as those of the acid-modified polyolefin resin.

Examples of the hydroxyl-containing (meth) acrylate include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, glycerol (meth) acrylate, and lactone modification (meth) Hydroxyethyl acrylate, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, etc .; containing as above Examples of the hydroxy vinyl ether include 2-hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, and 4-hydroxybutyl vinyl ether.

(Hardener (C))

Examples of the curing agent (C) used in the present invention include epoxy compounds, polyisocyanates, carbodiimides, The selected hardener for oxazoline and melamine resins. As a preferable content of the hardening agent, the mass% of the hardening agent (C) (the hardening agent) that satisfies the total mass of the solid content of the modified polyolefin resin (A) and the modified polyolefin resin (B) is mentioned. (C) The mass / (the mass of the modified polyolefin resin (A) + the mass of the modified polyolefin resin (B))) is in a range of 0.5 to 5 (mass%). If it is less than 0.5% by mass, it will result in poor electrolyte resistance. If it is more than 5% by mass, initial strength and electrolyte resistance will be poor, and the problems of the present invention will not be solved.

As the hardener of the present invention, an epoxy compound is particularly preferred.

Examples include ethylene glycol, propylene glycol, hexanediol, neopentyl glycol, trimethylolethane, trimethylolpropane, neopentaerythritol, glycerol, diglycerol, sorbitol, spiroglycerin, or hydrogenated A diglycidyl ether type epoxy resin of a polyhydric alcohol such as bisphenol A.

In addition, diglycidyl ether type epoxy resins such as bisphenol A, bisphenol F, bisphenol S, and bisphenol AD, phenol novolac resin, or glycidyl ether of cresol novolac resin, novolac type Aromatic epoxy resins such as epoxy resins; polyglycidyl ether epoxy resins of polyhydric alcohols such as ethylene oxide or propylene oxide adducts of aromatic polyhydroxy compounds Resin.

In addition, polyglycidol of polyether polyols such as polyethylene glycol, polypropylene glycol, or polytetramethylene glycol can be cited. Ether type epoxy resin; rings of bis (3,4-epoxycyclohexylmethyl) adipate, 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxy cyclohexylformate, etc. Polyaliphatic epoxy resin.

In addition, polyglycidyl ester type epoxy resins of polyacids such as malonic acid, butanedioic acid, adipic acid, phthalic acid, terephthalic acid, or trimellitic acid can be cited; butadiene Bisepoxy resins such as hexadiene, octadiene, dodecadiene, cyclooctadiene, α-pinene or vinyl cyclohexene.

Further examples include epoxy resins of diene polymers such as polybutadiene or polyisoprene; or tetraglycidyl diamino diphenylmethane, tetraglycidyl bisamino methylcyclohexyl Glycidylamine type epoxy resins such as alkane, diglycidylaniline or tetraglycidylxylylenediamine, Or hydantoin-containing epoxy resin containing various heterocycles.

Among these, when an aromatic epoxy resin such as a bisphenol A epoxy resin is used, it is preferable because it has good adhesion and corrosion resistance.

Specific examples of the bisphenol A epoxy resin include "EPICLON 850, 860, 1050, 1055, and 2055" made by DIC, and "jER828, 834, 1001, and 1002" made by Mitsubishi Chemical Corporation. 1004, 1007 "and so on.

The epoxy resin may include an epoxy compound having two or more epoxy groups in one molecule, one or more hydroxyl groups in one molecule, and an epoxy compound having a weight average molecular weight of 3,000 or less as an essential component.

As the polyisocyanate, a well-known diisocyanate and various compounds derived therefrom can be preferably used.

Examples include: 2,4-toluylene diisocyanate (2,4-tolylene diisocyanate), 2,6-toluene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, 1,5-naphthalene diisocyanate, hexamethylene diisocyanate, bis ( 4-isocyanatocyclohexyl) methane, diisocyanates such as hydrogenated diphenylmethane diisocyanate, and compounds derived therefrom, that is, trimeric isocyanate bodies, adducts, and biuret types of the aforementioned diisocyanates , Isocyanate dimers (uretdione), urethanes, prepolymers with isocyanate residues (oligomers obtained from diisocyanates and polyols), or composites of these, etc. The agent may be a compound obtained by reacting a compound having reactivity with an isocyanate group with a part of the isocyanate group of the isocyanate compound.

Examples of compounds having reactivity with isocyanate groups include compounds containing amine groups such as butylamine, hexylamine, octylamine, 2-ethylhexylamine, dibutylamine, ethylenediamine, benzylamine, and aniline. ; Methanol, ethanol, propanol, isopropanol, butanol, hexanol, octanol, 2-ethylhexanol, dodecanol, ethylene glycol, propylene glycol, benzyl alcohol, phenol and other compounds containing hydroxyl groups; Propyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol glycidyl ether, cyclohexanedimethanol diglycidyl ether, etc. Compounds having an epoxy group; compounds containing a carboxylic acid, such as acetic acid, butyric acid, hexanoic acid, caprylic acid, succinic acid, adipic acid, sebacic acid, and phthalic acid.

Examples of the carbodiimide include N, N'-di-o-tolylmethylcarbodiimide, N, N'-diphenylcarbodiimide, N, N'-di-2,6- Dimethylphenylcarbodiimide, N, N'-bis (2,6-diisopropylphenyl) carbodiimide , N, N'-bis (octadecyl) carbodiimide, N-toluenyl-N'-cyclohexylcarbodiimide, N, N'-di-2,2-tert-butyl Phenylcarbodiimide, N-toluenyl-N'-phenylcarbodiimide, N, N'-di-p-aminophenylphenylcarbodiimide, N, N'-di-p-hydroxyphenyl Carbodiimide, N, N'-dicyclohexylcarbodiimide, N, N'-di-p-toluenemethylcarbodiimide and the like.

As Examples of oxazoline: 2- Oxazoline, 2-methyl-2- Oxazoline, 2-phenyl-2- Oxazoline, 2,5-dimethyl-2- Oxazoline, 2,4-diphenyl-2- Oxazoline Oxazoline compounds, 2,2 '-(1,3-phenylene) -bis (2- Oxazoline), 2,2 '-(1,2-ethylene) -bis (2- Oxazoline), 2,2 '-(1,4-butylene) -bis (2- Oxazoline), 2,2 '-(1,4-phenylene) -bis (2- Oxazoline) and the like.

Examples of the amine-based resin include melamine resin and benzoguanidine Resin, urea resin, etc.

(Other additives)

In the present invention, as other additives, a well-known and commonly used thermoplastic elastomer, tackifier, catalyst, phosphoric acid compound, reactive elastomer, or silane coupling agent can be used. The content of these additives can be appropriately adjusted and used within a range that does not impair the function of the adhesive of the present invention.

(Solution stability)

In the present invention, with respect to the total mass of the solid content of the modified polyolefin resin (A) and the modified polyolefin resin (B), the modified polyolefin resin (B) is 0.1 to 20% by mass. It can be used as a laminating adhesive composition having characteristics of both electrolyte resistance and solution stability. Here, the solution stability is a mixed solvent of methylcyclohexane: 72 g and ethyl acetate: 8 g, and the resin of the test substance is added: 20 g, and the resin is dissolved. Then, when it was left to stand at 25 degreeC for 5 days, it evaluated whether the precipitate was confirmed.

In the case where the solution stability is excellent, the coating liquid can be uniformly applied in the coating step to obtain a uniform film thickness, and there is an advantage that a stable adhesive strength can be obtained.

In the case of less than 0.1% by mass, the solution stability is good, but the electrolyte resistance results are deteriorated. If it is more than 20% by mass, the solution stability is poor, and the problem of the present invention cannot be solved.

(Laminated body)

The laminate system of the present invention uses the adhesive composition for laminates of the present invention to combine one or more of a metal layer such as aluminum foil with a polyolefin sheet such as polyethylene and polypropylene, a polyester such as polyethylene terephthalate, and the like. This kind of plastic layer is laminated.

The adhesive composition for lamination of the present invention can be dissolved / dispersed in an appropriate solvent such as an ester-based solvent, a ketone-based solvent, an aromatic hydrocarbon, an aliphatic hydrocarbon, or an alicyclic hydrocarbon. Among the agents, a known coating method such as a roll coating method, a gravure coating method, or a bar coating method is applied to a metal foil and dried to form an adhesive layer.

The dry coating weight of the adhesive composition for lamination according to the present invention is preferably in a range of 0.5 to 20.0 g / m ² . If it is less than 0.5 g / m ² , it will cause difficulty in the uniformity of the coating film thickness. On the other hand, if it exceeds 20.0 g / m ² , the solvent removal property after coating is low, except that the processability is significant. In addition to the decrease, the problem of residual solvents also arises.

After the adhesive composition for a laminate of the present invention is coated on one side of the above-mentioned metal foil, a plastic layer is laminated and adhered by a dry lamination method, thereby obtaining a laminate of the present invention. The temperature of the lamination roll is about room temperature to about 120 ° C, and the pressure is preferably about 3 to 300 kg / cm ² .

The laminated body of the present invention is preferably aged after being manufactured. The aging conditions preferably have a temperature of 25 to 80 ° C and a time of 12 to 240 hours, during which bonding strength occurs.

(Secondary battery)

The laminated body of the present invention can be used as an electrolyte sealing film or an electrode part protection film of a primary or secondary battery. In this case, the plastic layer is used in contact with a polar organic solvent and / or salts. In particular, it is used in a state of being in contact with a polar organic solvent and a nonaqueous electrolyte containing a salt, and is particularly suitable for use as a secondary battery electrolyte sealing film for a nonaqueous electrolyte battery, a solid battery, or a protective film for a secondary battery electrode. In this case, the plastic layer can be used as a sealed bag for a battery by heat-sealing the plastic layer in a facing manner. The adhesive used in the present invention is excellent in heat sealability and prevents leakage of the non-aqueous electrolyte, and can be used for a long time in terms of batteries.

Examples of the polar organic solvent include aprotic polar solvents such as alkyl carbonate, ester, and ketone. Specific examples include ethylene carbonate, propylene carbonate, butene carbonate, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, γ-butyrolactone, and 1,2-dimethoxy Ethane, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxolane, 4-methyl-1,3-dioxolane, methyl formate, 4-methyl-1,3 formate -Dioxomethyl, methyl acetate, methyl propionate, etc.

Examples of the salt include alkali metal salts such as lithium salts, sodium salts, and potassium salts. For batteries, lithium salts such as LiPF ₆ , LiBF ₄ , and Li-fluorene imine are generally used.

The non-aqueous electrolyte is obtained by dissolving the above-mentioned alkali metal salt in an aprotic polar organic solvent such as a cyclic carbonate, a chain carbonate, or a mixture thereof at 0.5 to 3 mmoL.

Even if the laminated body of the present invention is used in a state of a non-aqueous electrolyte with the above-mentioned polar solvent and / or salt, especially a mixture thereof, the metal layer, the adhesive layer, and the plastic layer do not peel off between layers, and can be used. Used for a long time.

The battery of the present invention is a battery having a battery electrolyte sealing film or a battery electrode portion protective film including the laminate. The battery of the present invention can be used stably for a long period of time because the thin film does not cause interlayer peeling and prevents leakage of the non-aqueous electrolyte.

As described above, the laminated body of the present invention has excellent adhesion between the metal layer and the plastic layer, and has excellent durability against polar organic solvents or salts. Interlayer peeling does not occur even in contact with a non-aqueous electrolyte. Therefore, a battery using such a laminate as a battery electrolyte sealing film or a protective film for a battery electrode portion, and a secondary battery using a secondary battery electrolyte sealing film or a protective film for a battery electrode portion can be stable for a long period of time. use.

In addition, the laminate adhesive of the present invention has excellent adhesion to metal layers and plastic layers, and also has electrolyte resistance. Because of its high retention rate, the laminate obtained by using the adhesive has both electrolyte resistance. It is suitable for use as a laminate for a secondary battery because it does not cause interlayer peeling over time.

[Example]

Hereinafter, the present invention will be specifically described using examples. Mark " "Indicates mass parts.

(Example 1)

100 parts of HARDLEN NS-2002, 0.05 parts of EXCEREX 15341PA, 0.01 parts of CUREZOL 1B2MZ, 0.01 parts of triphenylphosphine, 0.2 parts of PINICRYSTAL KE359, 0.4 parts of EPICLON 860 were evenly stirred, and 5 g / m ² (dry) was applied to aluminum foil, dried at 80 ° C. for 1 minute, and then bonded to a CPP film (polyolefin film “ZK-93KM” 70 μm (manufactured by Toray Advanced Film)) at 100 ° C. to prepare a coated article (Laminated body 1). After the laminated body 1 was aged at 70 ° C for 5 days, the initial adhesion strength was measured.

(Example 2) ~ (Example 6)

An adhesive was prepared in the same manner as in Example 1 except that the components described in Table 1 were prepared. Furthermore, the laminated body of each Example was produced by the same manufacturing method as the laminated body 1.

The laminated body obtained by each Example was evaluated for the adhesive performance and electrolyte resistance (retention rate). The results are shown in Table 1.

The conditions of each test are as follows.

(Measurement of initial bonding strength)

In the Tensilon test made by A & D (stock), the sample was cut to a width of 15 mm, and the 180 ° peel strength (N / 15 mm) was measured.

(Retention rate of electrolyte resistance)

The laminated body was immersed in an electrolytic solution "ethyl carbonate: ethyl methyl carbonate: dimethyl carbonate = 1: 1: 1 (wt%) + LiPF ₆ : 1 moL + vinyl carbonate: 1 wt%" at 85 ° C for 7 days. The evaluation was performed from the retention rate of the adhesive strength before and after the immersion as follows.

○: 80% or more, △: 80 to 60%, ×: 60% or less

(Solution stability)

To a mixed solvent of methylcyclohexane: 72 g and ethyl acetate: 8 g, a resin of the test substance was added: 20 g. After dissolving the resin, it was left to stand at 25 ° C. for 5 days to check whether the precipitates can be confirmed. It is evaluated as follows.

○: No precipitate was confirmed ×: Precipitate was confirmed

‧HARDLEN NS-2002 (manufactured by Toyobo) modified polyolefin resin Melting point 69.7 ℃ Solid content 20%

‧EXCEREX 15341PA (manufactured by Mitsui Chemicals) modified polyolefin resin Melting point 131.7 ℃, 139.6 ℃ Solid content 100%

‧AUROREN 550S (manufactured by Nippon Paper Co., Ltd.) Modified polyolefin resin Melting point 82.9 ° C Solid content 100%

‧GMP1000E (manufactured by LOTTE CHEMICAL) modified polyolefin resin Melting point 94.3 ℃ Solid content 100%

‧CUREZOL 1B2MZ (manufactured by Shikoku Chemical Industry Co., Ltd.) imidazole 100% solid content

‧PINECRYSTAL KE359 (manufactured by Arakawa Chemical Industry Co., Ltd.) Tackifier Solid content 100%

‧FTR8120 (Mitsui Chemical Co., Ltd.) Thickener Solids 100%

‧EPICLON 860 (manufactured by DIC Corporation) bisphenol A epoxy resin epoxy equivalent 240 solid content 100%

‧EPICLON N-695 (manufactured by DIC Corporation) novolac epoxy resin epoxy equivalent 215 solid content 100%

(Comparative Example 1) ~ (Comparative Example 5)

As a comparative example, a laminated body was produced in the same manner as in the example except that it was prepared as shown in Table 2. The laminated body was evaluated for initial adhesion strength and electrolyte resistance (retention). The results are shown in Table 2.

‧HARDLEN NS-2002 (manufactured by Toyobo) modified polyolefin resin Melting point 69.7 ℃ Solid content 20%

‧EXCEREX 15341PA (manufactured by Mitsui Chemicals) modified polyolefin resin Melting point 131.7 ℃, 139.6 ℃ Solid content 100%

‧CUREZOL 1B2MZ (manufactured by Shikoku Chemical Industry Co., Ltd.) imidazole 100% solid content

‧FTR8120 (Mitsui Chemical Co., Ltd.) Thickener Solids 100%

‧EPICLON N-695 (manufactured by DIC Corporation) novolac epoxy resin epoxy equivalent 215 solid content 100%

From the above results, it can be seen that the adhesive composition for a laminate which satisfies the constitutional requirements of the present invention is an adhesive composition for a laminate having a high retention rate of electrolyte resistance and excellent solution stability.

Claims (9)

An adhesive composition for lamination, which comprises a modified polyolefin resin (A) having a melting point of 90 ° C. or lower, and a modified polymer having a melting point higher than that of the modified polyolefin resin (A) and 140 ° C. or lower. The olefin resin (B) and the hardener (C), wherein the modified polyolefin resin (B) is based on the total mass of the solid content of the modified polyolefin resin (A) and the modified polyolefin resin (B). ) Is 0.1 to 20% by mass. For example, the laminating adhesive composition for claim 1, wherein the difference between the melting points of the modified polyolefin resin (A) and the modified polyolefin resin (B) is 5 ° C to 80 ° C. For example, the laminating adhesive composition of claim 1 or 2, wherein the modified polyolefin resin (A) and the modified polyolefin resin (B) have an acid value of 1 to 200 mgKOH / g, and / or a hydroxyl value 1 ~ 200mgKOH / g, and the melting point is 60 ° C to 140 ° C. The laminating adhesive composition according to any one of claims 1 to 3, wherein the hardener (C) is selected from the group consisting of an epoxy compound, a polyisocyanate, a carbodiimide, Oxazolines, and amine-based resins. For example, the adhesive composition for a buildup of claim 4, wherein the epoxy compound has two or more epoxy groups in one molecule, one or more hydroxyl groups in one molecule, and a weight average molecular weight of 3,000 or less. The laminating adhesive composition according to any one of claims 1 to 5, wherein the hardener is relative to the total mass of the solid content of the modified polyolefin resin (A) and the modified polyolefin resin (B). (C) Quality % (Mass of hardener (C) / (mass of modified polyolefin resin (A) + mass of modified polyolefin resin (B))) is in a range of 0.5 to 5 (mass%). The laminating adhesive composition according to any one of claims 1 to 6, further comprising a thermoplastic elastomer, a tackifier, a catalyst, a phosphoric acid compound, a reactive elastomer, or a silane coupling agent. A laminate comprising a metal layer and a polyolefin resin layer, wherein the laminate adhesive composition according to any one of claims 1 to 7 is used as an adhesive between the metal layer and the polyolefin resin layer. A secondary battery using the laminated body as claimed in claim 8 as an electrolytic solution sealing film or an electrode portion protective film.