JP6825677B2 - Adhesives, laminates, battery packaging and batteries - Google Patents

Description

The present invention relates to an adhesive, specifically a polyolefin-based adhesive suitable for adhering a resin base material and a metal base material, a laminate obtained by using the adhesive, an exterior material for a secondary battery, and a battery.

A secondary battery represented by a lithium ion battery has a configuration in which a positive electrode, a negative electrode, and an electrolytic solution or the like are sealed between them. Further, as an encapsulation bag for encapsulating lead wires for taking out electricity of the positive electrode and the negative electrode to the outside, a heat seal layer made of an olefin resin, a metal base material made of a metal foil such as an aluminum foil or a metal vapor deposition layer, and a plastic. It is known to use a laminated body obtained by laminating the above (Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 09-283101 Japanese Unexamined Patent Publication No. 2007-294381

However, since the olefin resin is non-polar, it is difficult to bond it to a metal substrate. Further, when assembling a battery using the above-mentioned laminate, the battery element is sealed by heat-sealing the sealant layers located on the periphery of the battery element to seal the battery element. Therefore, the adhesive for bonding the heat seal layer and the metal base material needs heat resistance in addition to the adhesiveness between the non-polar base material such as olefin resin and the metal base material.

The present invention has been made in view of such a situation, and an object of the present invention is to provide an adhesive having excellent adhesiveness and heat resistance between a non-polar base material such as an olefin resin and a metal base material. To do. Further, it is an object of the present invention to provide a laminate obtained by using such an adhesive, a secondary battery exterior material and a battery obtained by using the laminate.

The present invention contains an olefin resin (A), a curing agent (B) containing an epoxy compound, and an acid anhydride (C), and the blending amount of the acid anhydride (C) is 100 parts by mass of the olefin resin (A). The present invention relates to an adhesive having a weight of 0.05 parts by mass or more and 10 parts by mass or less.

The adhesive of the present invention is excellent in adhesiveness and heat resistance between a non-polar base material such as an olefin resin and a metal base material. Further, the laminate of the present invention is excellent in adhesiveness and heat resistance.

<Adhesive>
The adhesive of the present invention contains an olefin resin (A), a curing agent containing an epoxy compound (B), and an acid anhydride (C). Hereinafter, each component of the adhesive of the present invention will be described in detail.

Examples of the olefin resin (A) used in the adhesive of the present invention include homopolymers and copolymers of olefin monomers, copolymers of olefin monomers and other monomers, and hydrides, halides, and acids of these polymers. Examples thereof include polymers mainly composed of a hydrocarbon skeleton, such as a modified product having a functional group introduced such as a hydroxyl group or a hydroxyl group, and one type or a combination of two or more types can be used. It is preferable to use a crystalline olefin resin having an acid group or an acid anhydride group, or a crystalline olefin resin having a hydroxyl group.

The olefin resin having an acid group or an acid anhydride group is an acid-modified olefin resin (A-1) which is a copolymer of an olefin monomer and an ethylenically unsaturated carboxylic acid or an ethylenically unsaturated carboxylic acid anhydride. Examples thereof include an acid-modified olefin resin (A-2), which is a resin obtained by graft-modifying an ethylenically unsaturated carboxylic acid or an ethylenically unsaturated carboxylic acid anhydride on a polyolefin.

Examples of the olefin-based monomer used for preparing the acid-modified olefin resin (A-1) include olefins having 2 to 8 carbon atoms, for example, ethylene, propylene, isobutylene, 1-butene, 4-methyl-1-pentene, and the like. Examples include hexene and vinylcyclohexane. Among these, olefins having 3 to 8 carbon atoms are preferable, propylene and 1-butene are more preferable, and propylene and 1-butene are particularly used in combination with respect to the solvent because the adhesive strength is particularly good. It is preferable because it has excellent resistance and adhesive strength.

Examples of the ethylenically unsaturated carboxylic acid or ethylenically unsaturated carboxylic acid anhydride used for copolymerization with an olefin-based monomer include acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid, mesaconic acid, and maleic anhydride. Acid, 4-methylcyclohexe-4-ene-1,2-dicarboxylic acid anhydride, bicyclo [2.2.2] octo-5-ene-2,3-dicarboxylic acid anhydride, 1,2,3 4,5,8,9,10-Octahydronaphthalene-2,3-dicarboxylic acid anhydride, 2-octa-1,3-diketospiro [4.4] non-7-ene, bicyclo [2.2.1] ] Hept-5-ene-2,3-dicarboxylic acid anhydride, maleopimaric acid, tetrahydrophthalic acid anhydride, methyl-bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylic acid anhydride, Examples thereof include methyl-norbornen-5-ene-2,3-dicarboxylic acid anhydride, norborn-5-ene-2,3-dicarboxylic acid anhydride. Among these, the reactivity with the olefin-based monomer and the reactivity of the acid anhydride after copolymerization are particularly excellent, and the molecular weight of the compound itself is small and the functional group concentration is high when it is made into a copolymer. Therefore, maleic anhydride is preferable. These can be used alone or in combination of two or more.

For the preparation of the acid-modified olefin resin (A-1), in addition to the olefin-based monomer, the tylene unsaturated carboxylic acid or the ethylenically unsaturated carboxylic acid anhydride, other compounds having an ethylenically unsaturated group, for example, styrene, You may use butadiene, isoprene and the like together.

Examples of the polyolefin used for preparing the acid-modified olefin resin (A-2) include homopolymers and copolymers of olefins having 2 to 8 carbon atoms, and copolymers of olefins having 2 to 8 carbon atoms and other monomers. Examples thereof include copolymers, and specific examples thereof include polyethylenes such as high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene resins, polypropylene, polyisobutylene, and poly (1-butene). Poly (4-methyl-1-pentene), polyvinylcyclohexane, ethylene / propylene block copolymer, ethylene / propylene random copolymer, ethylene / 1-butene copolymer, ethylene / 4-methyl-1-pentene copolymer Combined, α-olefin copolymer such as ethylene / hexene copolymer, ethylene / vinyl acetate copolymer, ethylene / methyl methacrylate copolymer, ethylene / vinyl acetate / methyl methacrylate copolymer, propylene / 1-butene Examples thereof include copolymers. Among these, a homopolymer of an olefin having 3 to 8 carbon atoms and two or more copolymers of an olefin having 3 to 8 carbon atoms are preferable from the viewpoint of particularly good adhesive strength, and propylene alone. A polymer or a propylene / 1-butene copolymer is more preferable, and a propylene / 1-butene copolymer is particularly preferable because it has excellent resistance to a solvent and excellent adhesive strength.

The ethylenically unsaturated carboxylic acid or ethylenically unsaturated carboxylic acid anhydride used for graft modification with polyolefin is used for copolymerization with an olefin-based monomer in the preparation of the acid-modified olefin resin (A-1) described above. The same ones that can be used can be used. Maleic anhydride is preferable because the reactivity of the functional group after the graft modification is high and the concentration of the functional group of the graft-modified polyolefin is high. These can be used alone or in combination of two or more.

To react an ethylenically unsaturated carboxylic acid or an ethylenically unsaturated carboxylic acid anhydride with a polyolefin by graft modification, specifically, the polyolefin is melted and the ethylenically unsaturated carboxylic acid or the ethylenically unsaturated carboxylic acid is melted therein. A method of adding an acid anhydride (graft monomer) to cause a graft reaction, dissolving polyolefin in a solvent to prepare a solution, and adding ethylenically unsaturated carboxylic acid or ethylenically unsaturated carboxylic acid anhydride to the solution to cause a graft reaction. Method, Polyethylene dissolved in an organic solvent is mixed with ethylenically unsaturated carboxylic acid or ethylenically unsaturated carboxylic acid anhydride, heated at the softening temperature of the polyolefin or a temperature higher than the melting point, and radical polymerization and hydrogen in a molten state. Examples thereof include a method of simultaneously performing a withdrawal reaction.

In either case, in order to efficiently carry out the graft copolymerization of the graft monomer, it is preferable to carry out the graft reaction in the presence of a radical initiator. The graft reaction is usually carried out under the condition of 60 to 350 ° C. The ratio of the radical initiator used is usually in the range of 0.001 to 1 part by weight with respect to 100 parts by weight of the polyolefin before modification.

As the radical initiator, an organic peroxide is preferable, for example, benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di (peroxide benzoate) hexin-3, 1,4-Bis (tert-butylperoxyisopropyl) benzene, lauroyl peroxide, tert-butylperacetate, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexin-3,2,5-dimethyl- 2.5-di (tert-butylperoxy) hexane, tert-butylperbenzoate, tert-butylperphenylacetate, tert-butylperisobutyrate, tert-butylper-sec-octate, tert-butylperpivalate, ku Examples thereof include milper pivalate and tert-butylperdiethyl acetate. Other azo compounds such as azobisisobutyronitrile and dimethylazoisobutyrate can also be used.

The optimum radical initiator may be selected according to the graft reaction process, but usually dicumyl peroxide, di-tert-butyl peroxide, or 2,5-dimethyl-2,5-di (tert-butylperoxy) hexine. Dialkyl peroxides such as -3,2,5-dimethyl-2,5-di (tert-butylperoxy) hexane and 1,4-bis (tert-butylperoxyisopropyl) benzene are preferably used.

When an acid-modified olefin resin (A-1) or an acid-modified olefin resin (A-2) is used as the olefin resin (A), the adhesion of the metal layer is further improved and the electrolyte resistance is excellent. It is preferable to use one having an acid value of ~ 200 mgKOH / g.

As the olefin resin (A-3) having a hydroxyl group, a copolymer of polyolefin and a hydroxyl group-containing (meth) acrylic acid ester or a hydroxyl group-containing vinyl ether, or a hydroxyl group-containing (meth) acrylic acid ester or a hydroxyl group-containing vinyl ether grafted on a polyolefin. Examples include modified resins. As the polyolefin, the same polyolefin used for preparing the olefin resin (A-2) can be used. As the modification method, the same method as the method for adjusting the acid-modified olefin resins (A-1) and (A-2) can be used.

Examples of the hydroxyl group-containing (meth) acrylic acid ester used for modification include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, glycerol (meth) acrylate, lactone-modified hydroxyethyl (meth) acrylate, and polyethylene glycol mono (meth) acrylate. , Polypropylene glycol mono (meth) acrylate and the like.
Examples of the hydroxyl group-containing vinyl ether include 2-hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, 4-hydroxybutyl vinyl ether and the like.

When an olefin resin (A-3) having a hydroxyl group is used as the olefin resin (A), the adhesion of the metal layer is further improved and the electrolyte resistance is excellent. Therefore, a hydroxyl value of 1 to 200 mgKOH / g can be used. It is preferable to use the one that has.

As the olefin resin (A), the above-mentioned acid-modified olefin resin (A-2) or the polyolefin used for adjusting the olefin resin (A-3) having a hydroxyl group may be used as it is without modification.

The weight average molecular weight of the olefin resin (A) is preferably 40,000 or more in order to improve the adhesiveness. Further, the weight average molecular weight of the olefin resin (A) is preferably 150,000 or less in order to ensure appropriate fluidity.

In the present invention, the weight average molecular weight (Mw) and the number average molecular weight (Mn) are values measured by gel permeation chromatography (GPC) under the following conditions.

Measuring device; HLC-8320GPC manufactured by Tosoh Corporation
Column; TSKgel 4000HXL, TSKgel 3000HXL, TSKgel 2000HXL, TSKgel 1000HXL manufactured by Tosoh Corporation
Detector; RI (Differential Refractometer)
Data processing; Multi-station GPC-8020modelII manufactured by Tosoh Corporation
Measurement conditions; column temperature 40 ° C
Solvent tetrahydrofuran
Flow velocity 0.35 ml / min Standard; Monodisperse polystyrene sample; 0.2 mass% tetrahydrofuran solution in terms of resin solid content filtered through a microfilter (100 μl)

The melting point of the olefin resin (A) is preferably 50 ° C. or higher, more preferably 60 ° C. or higher, and even more preferably 65 ° C. or higher. The melting point of the olefin resin (A) is preferably 120 ° C. or lower, more preferably 90 ° C. or lower, and even more preferably 85 ° C. or lower.

The melting point of the olefin resin is measured by DSC (Differential Scanning Calorimetry). Specifically, after raising the temperature from the temperature at which the temperature falls to the temperature at which the temperature rises at 10 ° C./min, the temperature is cooled to the temperature at which the temperature falls at 10 ° C./min to remove the heat history, and then the temperature rises again at 10 ° C./min. The temperature rises to the point. The melting point is the peak temperature when the temperature is raised for the second time. Further, the temperature at which the temperature falls is set to a temperature 50 ° C. or higher lower than the crystallization temperature, and the temperature at which the temperature rises is reached is set to a temperature about 30 ° C. or higher higher than the melting point temperature. The temperature at which the temperature falls and the temperature at which the temperature rises rise are determined by trial measurement.

An epoxy compound is used as the curing agent (B). The compound is not particularly limited as long as it has an epoxy group in the molecule, and is not particularly limited, for example, ethylene glycol, propylene glycol, hexanediol, neopentyl glycol, trimethylolethane, trimethylolpropane, pentaerythritol, glycerin, diglycerin, sorbitol, and spiro. Polyglycidyl ether type epoxy resin of aliphatic polyol such as glycol or hydrogenated bisphenol A;
Bisphenol type epoxy resin such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD type epoxy resin;
Aromatic epoxy resins such as phenol novolac resin and novolac type epoxy resin which is glycidyl ale of cresol novolak resin;
Ethylene oxide of aromatic polyhydroxy compounds such as bisphenol A, bisphenol F, bisphenol S, bisphenol AD, or polyglycidyl ether of polyol which is an adduct of propylene oxide;
Polyglycidyl ether type epoxy resin of polyether polyol such as polyethylene glycol, polypropylene glycol or polytetramethylene glycol; bis (3,4-epoxycyclohexylmethyl) adipate, 3,4-epoxycyclohexylmethyl-3', 4'-epoxy Cyclic aliphatic polyepoxy resin such as cyclohexylcarboxylate;
Polyglycidyl ester type epoxy resin of polycarboxylic acid such as propanetricarboxylic acid, butanetetracarboxylic acid, adipic acid, phthalic acid, terephthalic acid or trimellitic acid;
Hydrocarbon diene bisepoxy resins such as butadiene, hexadiene, octadiene, dodecadien, cyclooctadiene, α-pinene or vinylcyclohexene;
Diene polymer epoxy resin such as polybutadiene or polyisoprene;
Glycidylamine type epoxy resins such as tetraglycidyldiaminodiphenylmethane, triglycidylparaaminophenol, tetraglycidylbisaminomethylcyclohexane, diglycidylaniline, and tetraglycidylmethoxylylenediamine;
Epoxy resins containing a heterocycle such as triazine and hydantoin can be mentioned.
These epoxy resins may be used alone or in combination of two or more.

Further, the epoxy compound used in the present invention is preferably an epoxy compound having two or more epoxy groups and one or more hydroxyl groups in one molecule and having a weight average molecular weight of 3000 or less.

A compound other than the epoxy resin may be used in combination as the curing agent (B). Other curing agents that can be used in combination with the epoxy resin include polyfunctional isocyanate compounds, aziridine group-containing compounds, carbodiimides, oxazolines, amino resins and the like.

Examples of the polyfunctional isocyanate compound include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, 1,5-naphthalenedi isocyanate, hexamethylene diisocyanate, and bis (4-isocyanate cyclohexyl). ) Diisocyanates such as methane or hydrogenated diphenylmethane diisocyanates and compounds derived from these, that is, prepolymers (diisocyanates) having isocyanurates, adducts, biuret types, uretdiones, allophanates, and isocyanate residues of the diisocyanates. And a low polymer obtained from polyol), or a complex thereof and the like.

A compound obtained by reacting a part of the isocyanate groups of the above-mentioned polyfunctional isocyanate compound with a compound having reactivity with the isocyanate group may be used as a curing agent. Compounds that have reactivity with isocyanate groups include amino group-containing compounds such as butylamine, hexylamine, octylamine, 2-ethylhexylamine, dibutylamine, ethylenediamine, benzylamine, and aniline: methanol, ethanol, propanol, and isopropanol. , Butanol, Hexanol, Octanol, 2-ethylhexyl alcohol, dodecyl alcohol, ethylene glycol, propylene glycol, benzyl alcohol, phenol and other compounds containing hydroxyl groups: allyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, neopentyl Compounds having an epoxy group such as glycol diglycidyl ether, 1,6-hexanediol glycidyl ether, cyclohexanedimethanol diglycidyl ether: acetic acid, butanoic acid, hexanoic acid, octanoic acid, succinic acid, adipic acid, sebacic acid, phthal Examples thereof include compounds containing carboxylic acids such as acids.

Examples of the aziridine group-containing compound include N, N'-hexamethylene-1,6-bis (1-aziridinecarboxyamide) and N, N'-diphenylmethane-4,4'-bis (1-aziridinecarboxyamide). , Trimethylolpropan-tri-β-aziridinyl propionate), N, N'-toluene-2,4-bis (1-aziridinecarboxyamide), triethylenemelamine, trimethylalopropan-tri-β (2) -Methylaziridine) propionate, bisisophthaloyl-2-methylaziridine, tri-1-aziridinylphosphine oxide, tris-1--2-methylaziridinephosphine oxide and the like can be mentioned.

Examples of carbodiimides include N, N'-di-o-toluyl carbodiimide, N, N'-diphenylcarbodiimide, N, N'-di-2,6-dimethylphenylcarbodiimide, and N, N'-bis (2,6-bis). Diisopropylphenyl) carbodiimide, N, N'-dioctyldecylcarbodiimide, N-triyl-N'-cyclohexylcarbodiimide, N, N'-di-2,2-tert. -Butylphenylcarbodiimide, N-triyl-N'-phenylcarbodiimide, N, N'-di-p-aminophenylcarbodiimide, N, N'-di-p-hydroxyphenylcarbodiimide, N, N'-di-cyclohexylcarbodiimide , N, N'-di-p-toluyl carbodiimide and the like.

Examples of the oxazoline include monooxazoline compounds such as 2-oxazoline, 2-methyl-2-oxazoline, 2-phenyl-2-oxazoline, 2,5-dimethyl-2-oxazoline and 2,4-diphenyl-2-oxazoline, 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 can be mentioned.

Examples of the amino resin include melamine resin, benzoguanamine resin, urea resin and the like.

The blending amount of the curing agent (B) is preferably 0.01 part by mass or more, more preferably 0.1 part by mass or more, and 0.5 part by mass with respect to 100 parts by mass of the olefin resin (A). It is more preferable to have more than one part. The amount of the curing agent (B) to be blended is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and 5 parts by mass or less with respect to 100 parts by mass of the olefin resin (A). Is even more preferable. Thereby, excellent adhesiveness and chemical resistance can be exhibited.

Examples of the acid anhydride (C) include cyclic aliphatic acid anhydrides, aromatic acid anhydrides, unsaturated carboxylic acid anhydrides, and the like, and one type or a combination of two or more types can be used. More specifically, for example, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic acid anhydride, dodecenyl succinic anhydride, polyazipic acid anhydride, polyazereic acid anhydride, polysevacinic acid. Anhydrous, poly (ethyloctadecanedioic acid) anhydride, poly (phenylhexadecanedioic acid) anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride , Methyl hymic acid anhydride, trialkyltetrahydrophthalic acid anhydride, methylcyclohexene dicarboxylic acid anhydride, methylcyclohexene tetracarboxylic acid anhydride, ethylene glycol bistrimericate dianhydride, het acid anhydride, nadic acid anhydride, Methylnadic acid anhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexane-1,2-dicarboxylic acid anhydride, 3,4-dicarboxy-1,2, Examples thereof include 3,4-tetrahydro-1-naphthalene succinic anhydride, 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic anhydride and the like.

Further, as the acid anhydride (C), the above-mentioned compound modified with glycol may be used. Examples of glycols that can be used for modification include alkylene glycols such as ethylene glycol, propylene glycol and neopentyl glycol; and polyether glycols such as polyethylene glycol, polypropylene glycol and potitetramethylene ether glycol. Furthermore, copolymerized polyether glycols of two or more kinds of these glycols and / or polyether glycols can also be used.

The blending amount of the acid anhydride (C) is preferably 0.05 parts by mass or more, and more preferably 0.8 parts by mass or more with respect to 100 parts by mass of the olefin resin (A). The amount of the acid anhydride (C) to be blended is preferably 10 parts by mass or less, and more preferably 8 parts by mass or less, based on 100 parts by mass of the olefin resin (A). As a result, the adhesiveness between the adhesive and the metal is improved, and it is possible to obtain an adhesive having excellent initial adhesive strength and adhesive strength after heat sealing.

The reason why the adhesive of the present invention is excellent in adhesiveness and heat resistance is not clear, but it is presumed as follows. The acid anhydride (C) used in the present invention has a polar group and has an excellent affinity for a metal substrate. Moreover, since the molecular weight is relatively small, it is relatively easy to move. It is considered that the applied adhesive moves to the metal base material side before it is completely cured and plays a role like a so-called anchoring agent, thereby contributing to the improvement of adhesiveness and heat resistance. On the other hand, if the amount of the acid anhydride (C) contained in the adhesive is too large, the acid anhydride (C) will form a pseudo-low strength layer between the metal base material and the adhesive. It is considered that the adhesiveness is lowered due to this.

The adhesive of the present invention can secure fluidity and exhibit appropriate coatability by further blending an organic solvent (D) in addition to the above components. The organic solvent is not particularly limited as long as it can be volatilized and removed by overheating in the drying step at the time of coating the adhesive, and for example, an aromatic organic solvent such as toluene or xylene; n-hexane, etc. An aliphatic organic solvent such as n-heptane; an alicyclic organic solvent such as cyclohexane and methylcyclohexane; a halogen-based organic solvent such as trichloroethylene, dichloroethylene, chlorobenzene and chloroform; a ketone solvent such as methylethylketone, methylisobutylketone and cyclohexanone. Ester solvents such as ethyl acetate and butyl acetate; Alcohol solvents such as ethanol, methanol, n-propanol, 2-propanol (isopropyl alcohol), butanol, hexanol; diisopropyl ether, butyl cellosolve, tetrahydrofuran, dioxane, butyl carbitol, etc. Ether-based solvent; glycol ether-based solvent such as diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, propylene glycol monomethyl ether; glycol ester-based solvent such as ethylene glycol monomethyl ether acetate, proprene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate Examples thereof include solvents, and these may be used alone or in combination of two or more.

Even when a non-chlorine olefin resin, an olefin resin having an acid group or an acid anhydride group, or an olefin resin having a hydroxyl group is used as the olefin resin (A), its solubility is excellent. It is preferable to use a mixed solvent of an organic solvent, an ester solvent, and an alcohol solvent. In particular, when an olefin resin having an acid group or an acid anhydride group is used, it is preferable to use a mixed solvent of methylcyclohexane, ethyl acetate and isopropyl alcohol because of its excellent solubility.

The amount of the organic solvent used is preferably such that the ratio of the olefin resin (A) to the total mass of the olefin resin (A) and the organic solvent (D) is 10 to 30% by mass. This makes it possible to obtain an adhesive having excellent coatability and wettability to a metal film.

As the adhesive of the present invention, various additives such as a tackifier, a plasticizer, a thermoplastic elastomer, a reactive elastomer, a phosphoric acid compound, a silane coupling agent, and an adhesion accelerator can be used, if necessary. The content of these additives may be appropriately adjusted within a range that does not impair the function of the adhesive of the present invention.

Examples of the tackifiers that can be used here include rosin-based or rosin ester-based tackifiers, terpene-based or terpene-phenol-based tackifiers, saturated hydrocarbon resins, kumaron-based tackifiers, and kumaron-inden-based tackifiers. Examples thereof include agents, styrene resin-based tackifiers, xylene resin-based tackifiers, phenol resin-based tackifiers, and petroleum resin-based tackifiers. Each of these may be used alone, or two or more types may be used in combination.

Examples of the plasticizer include polyisoprene, polybutene, procel oil and the like, and examples of the thermoplastic elastomer include a styrene-butadiene copolymer (SBS), a hydrogenated product of a styrene-butadiene copolymer (SEBS), SBBS, and a styrene-isoprene. Examples thereof include copolymerized hydrogenated products (SEPS), styrene block copolymers (TPS), olefin-based elastomers (TPO), and reactive elastomers obtained by acid-modifying these elastomers.

Examples of the phosphoric acid compound include phosphoric acids such as hypophosphoric acid, phosphoric acid, orthophosphoric acid and hypophosphoric acid, and condensed phosphoric acids such as metaphosphoric acid, pyrophosphoric acid, tripolyphosphoric acid, polyphosphoric acid and ultraphosphoric acid, for example. Monomethyl orthophosphate, monoethyl orthophosphate, monopropyl orthophosphate, monobutyl orthophosphate, mono-2-ethylhexyl orthophosphate, monophenyl orthophosphate, monomethyl phosphite, monoethyl phosphite, monopropyl phosphite, monobutyl phosphite , Mono-2-ethylhexyl phosphite, monophenyl phosphite, di-2-ethylhexyl orthophosphate, dimethyl diphenyl phosphite, diethyl phosphite, dipropyl phosphite, dibutyl phosphite, phosphite Monos such as di-2-ethylhexyl and diphenyl phosphite, diesterates, monos from condensed phosphoric acid and alcohols, diesterates, for example, the above phosphoric acids are added with epoxy compounds such as ethylene oxide and propylene oxide. Examples thereof include epoxy phosphoric acid esters obtained by adding the above-mentioned phosphoric acids to an aliphatic or aromatic diglycidyl ether.

Examples of the silane coupling agent include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, and N-β (aminoethyl) -γ-. Aminosilanes such as aminopropyltrimethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane; β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycid Epoxysilanes such as xypropyltriethoxysilane; vinylsilanes such as vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane; hexamethyldisilazane, γ-mercaptopropyl Examples thereof include trimethoxysilane.

Adhesion promoters include 2-methylimidazole, 1,2-dimethylimidazole, 2-phenyl-4-methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2. Imidazole compounds such as -ethyl-4-methylimidazole, triethylamine, triethylenediamine, N'-methyl-N- (2-dimethylaminoethyl) piperazin, 1,8-diazabicyclo [5.4.0] undecene (DBU) , 1,5-diazabicyclo [4.3.0] -nonen, 6-dibutylamino-1,8-diazabicyclo [5.4.0] Undecene and other tertiary amines and these tertiary amines are phenol and octyl. Compounds made into amine salts with acid, quaternized tetraphenylborate salt, etc., cationic catalysts such as triarylsulfonium hexafluoroantimonate, diallyliodonium hexafluoroantimonate, tributylphosphine, methyldiphenylphosphine, triphenylphosphine, tris (4) Examples thereof include organic phosphine compounds such as −methylphenyl) phosphine, tris (4-butylphenyl) phosphine, diphenylphosphine, and phenylphosphine. These may be used alone or in combination of two or more.

The adhesive of the present invention can be prepared by mixing each of the above-mentioned components. At this time, each component may be mixed at the same time to form an adhesive, but components other than the curing agent (B) may be mixed in advance to adjust the texture, and the curing agent (B) may be mixed when the adhesive is used. It is preferable to use a two-component adhesive because the adhesive is excellent in stability and workability.

The adhesive of the present invention is excellent in adhesiveness and heat resistance between a non-polar base material such as an olefin resin and a metal base material.

<Laminated body>
The laminate of the present invention is arranged between the first base material, the second base material, the first base material and the second base material, and is arranged between the first base material and the second base material. Includes an adhesive layer to bond with. The adhesive layer is a cured coating film of the above-mentioned adhesive. In addition to the first base material and the second base material, other base materials may be contained. The adhesive layer for bonding the first base material to the other base material and the second base material to the other base material may or may not be a cured coating film of the adhesive of the present invention. Good.

Examples of the first base material, the second base material, and other base materials include paper, olefin resin, acrylonitrile-butadiene-styrene copolymer (ABS resin), polyvinyl chloride resin, and fluororesin. Metals such as poly (meth) acrylic resin, carbonate resin, polyamide resin, polyimide resin, polyphenylene ether resin, synthetic resin film obtained from polyphenylene sulfide resin or polyester resin, copper foil, aluminum foil Foil or the like can be used.

Since the adhesive of the present invention has excellent adhesiveness between a non-polar base material such as an olefin resin and a metal base material, one of the first base material and the second base material is a non-polar base material. The other is preferably, but is not limited to, a metal base material.

The laminate of the present invention is obtained by applying the adhesive of the present invention to one of the first base material and the second base material, then laminating the other, and curing the adhesive. It is preferable to provide a drying step between the application of the adhesive and the laminating of the first base material and the second base material.
As the adhesive coating method, a gravure coater method, a microgravure coater method, a reverse coater method, a bar coater method, a roll coater method, a die coater method and the like can be used. The amount of the adhesive applied is preferably adjusted so that the applied weight after drying is 0.5 to 20.0 g / m ² . If it is less than 0.5 g / m ² , the continuous uniform coating property is likely to be lowered, and if it is more than 20.0 g / m ² , the solvent releasability after coating is also lowered, and problems of workability and residual solvent are likely to occur. Become.

The temperature of the laminating roll when laminating the first base material and the second base material is preferably 25 to 120 ° C., and the pressure is preferably ³ to 300 kg / cm ² .
It is preferable to provide an aging step after laminating the first base material and the second base material. The aging conditions are preferably 25 to 100 ° C. and 12 to 240 hours.

<Battery packaging material>
As an example, the packaging material for a battery of the present invention has a first base material, a second base material, a third base material, a first base material, and a second base material bonded together. It includes an adhesive layer and a second adhesive layer for bonding the second base material and the third base material. The first base material is a polyolefin film, and the second base material is a metal foil. The third base material is a resin film such as nylon or polyester. The first adhesive layer is a cured coating film of the adhesive of the present invention. The second adhesive layer may or may not be a cured coating of the adhesive of the present invention. Another substrate may be placed on the opposite side of the third substrate from which the second adhesive layer is provided, with or without an adhesive layer, or a coating layer may be provided. Good. It is not necessary to provide another base material or coating layer.

The polyolefin film may be appropriately selected from conventionally known olefin resins. For example, although not particularly limited, polyethylene, polypropylene, ethylene propylene copolymer and the like can be used. It is preferably a non-stretched film. The film thickness of the polyolefin film is not particularly limited, but is preferably 10 μm or more, more preferably 20 μm or more, and further preferably 25 μm or more. Further, it is preferably 100 μm or less, more preferably 95 μm or less, and further preferably 90 μm or less.
The first base material functions as a sealant layer when the battery packaging materials of the present invention are heat-sealed and bonded to each other when the battery described later is manufactured.

Examples of the metal foil include aluminum, copper, nickel and the like. These metal foils are sandblasted, polished, degreased, etched, surface-treated by rust preventive immersion or spraying, trivalent chromium chemical conversion treatment, phosphate chemical conversion treatment, sulfide chemical conversion treatment, anodic oxide film formation, etc. It may be surface-treated such as a fluororesin coating. Among these, those subjected to trivalent chromium chemical conversion treatment are preferable because they are excellent in adhesion retention performance (environmental deterioration resistance) and corrosion resistance. Further, the thickness of this metal film is preferably in the range of 10 to 100 μm from the viewpoint of corrosion prevention.

Examples of the resin film that can be used as the third base material include polyester resin, polyamide resin, epoxy resin, acrylic resin, fluororesin, polyurethane resin, silicon resin, phenol resin, and resins such as mixtures and copolymers thereof. The film is mentioned. Among these, polyester resin and polyamide resin are preferable, and biaxially stretched polyester resin and biaxially stretched polyamide resin are more preferable. Specific examples of the polyester resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, copolymerized polyester, and polycarbonate. Specific examples of the polyamide resin include nylon 6, nylon 6, 6, a copolymer of nylon 6 and nylon 6, 6, nylon 6, 10, and polymethoxylylen adipamide (MXD6). Be done.

The coating layer can be formed of, for example, polyvinylidene chloride, polyester resin, urethane resin, acrylic resin, epoxy resin, or the like. It is preferably formed of a two-component curable resin. Examples of the two-component curable resin forming the coating layer include a two-component curable urethane resin, a two-component curable polyester resin, and a two-component curable epoxy resin. Moreover, you may mix the matting agent in the coating layer.

Examples of the matting agent include fine particles having a particle size of about 0.5 nm to 5 μm. The material of the matting agent is not particularly limited, and examples thereof include metals, metal oxides, inorganic substances, and organic substances. The shape of the matting agent is also not particularly limited, and examples thereof include a spherical shape, a fibrous shape, a plate shape, an amorphous shape, and a balloon shape. Specific examples of the matting agent include talc, silica, graphite, kaolin, montmoriloid, montmorillonite, synthetic mica, hydrotalcite, silica gel, zeolite, aluminum hydroxide, magnesium hydroxide, zinc oxide, magnesium oxide, and aluminum oxide. , Neodium oxide, Antimon oxide, Titanium oxide, Serium oxide, Calcium sulfate, Barium sulfate, Calcium carbonate, Calcium silicate, Lithium carbonate, Calcium benzoate, Calcium silicate, Magnesium stearate, Carbon black, Carbon nanotubes, High melting point Examples thereof include nylon, crosslinked acrylic, crosslinked styrene, crosslinked polyethylene, benzoguanamine, gold, aluminum, copper and nickel. These matting agents may be used alone or in combination of two or more. Among these matting agents, preferably silica, barium sulfate, and titanium oxide are mentioned from the viewpoint of dispersion stability and cost. Further, the matting agent may be subjected to various surface treatments such as an insulating treatment and a highly dispersible treatment on the surface.

Such a laminate is molded so that the polyolefin film, which is the first base material, is inside the third base material when it is used as a battery, and becomes the secondary battery exterior material of the present invention. The molding method is not particularly limited, and examples thereof include the following methods.

-Heat-compressed air molding method: The packaging material for batteries is sandwiched between a lower mold with holes for supplying high-temperature and high-pressure air and an upper mold with pocket-shaped recesses, and air is supplied while being heated and softened to form recesses. how to.
-Preheater flat plate type compressed air molding method: After heating and softening the packaging material for batteries, air is supplied by sandwiching it between a lower mold with holes for supplying high-pressure air and an upper mold with pocket-shaped recesses. A method of forming a recess.
-Drum type vacuum forming method: A method in which a battery packaging material is partially heated and softened with a heating drum, and then the concave portion of a drum having a pocket-shaped concave portion is evacuated to form the concave portion.
-Pin molding method: A method in which the bottom material sheet is heat-softened and then crimped with a pocket-shaped uneven mold.
-Preheater plug assist compressed air molding method: After heating and softening the packaging material for batteries, air is supplied by sandwiching it between a lower mold with holes for supplying high-pressure air and an upper mold with pocket-shaped recesses. A method of forming a concave portion, which assists molding by raising and lowering a convex plug at the time of molding.

Since the wall thickness of the bottom material after molding is uniform, the preheater plug assist compressed air molding method, which is a heating vacuum forming method, is preferable.
The battery packaging material of the present invention thus obtained can be suitably used as a battery container for sealing and accommodating battery elements such as a positive electrode, a negative electrode, and an electrolyte.

<Battery>
The battery of the present invention is a battery in which a battery element provided with a positive electrode, a negative electrode, and an electrolyte is projected outward with metal terminals connected to each of the positive electrode and the negative electrode in the battery packaging material of the present invention. It is obtained by covering the peripheral edge of the element so that a flange portion (a region where the sealant layers come into contact with each other) can be formed, and heat-sealing the sealant layers of the flange portion with each other.

The battery obtained by using the battery packaging material of the present invention may be either a primary battery or a secondary battery, but is preferably a secondary battery. The secondary battery is not particularly limited, and for example, a lithium ion battery, a lithium ion polymer battery, a lead storage battery, a nickel / hydrogen storage battery, a nickel / cadmium storage battery, a nickel / iron storage battery, a nickel / zinc storage battery, a silver oxide / zinc storage battery, etc. Examples thereof include metal air batteries, multivalent cation batteries, capacitors, and capacitors. Among these secondary batteries, lithium ion batteries and lithium ion polymer batteries can be mentioned as suitable application targets of the battery packaging material of the present invention.

Hereinafter, the present invention will be described with reference to Examples and Comparative Examples, but the present invention is not limited thereto. The composition and other values are based on mass unless otherwise specified.

(Example 1)
100 parts of Toyotac PMA-L as olefin resin (A), 0.05 parts of triphenylphosphine, 1.0 part of FTR-8120, 0.1 part of EPICLON B-570-H as acid anhydride (C) , Was dissolved in a mixed solvent (cyclomethylhexane / ethyl acetate / isopropyl alcohol = 71/8/1) to give a non-volatile content of 20%. Next, 2.0 parts of Denacol EX-321 was added as a curing agent (B) containing an epoxy compound, and the mixture was well stirred to prepare the adhesive of Example 1.

The prepared adhesive was applied to the glossy surface of an aluminum foil (aluminum foil "1N30H" manufactured by Toyo Aluminum Co., Ltd .: film thickness 30 μm) with a bar coater at a coating amount of 2 g / m ² (dry), and dried at 80 ° C. for 1 minute. After that, it was bonded to an unstretched polyolefin film (“ET-20” film thickness manufactured by Okamoto Co., Ltd .: 40 μm) at 100 ° C. Next, on the matte surface of the aluminum foil, "Dick Dry LX-906" (manufactured by DIC Corporation) is used as the main agent, and "KW-75" (manufactured by DIC Corporation) is used as the curing agent, and the weight ratio is the main agent / curing agent = 100. The adhesive blended so as to be 1/10 was applied with a bar coater at a coating amount of 4 g / m ² (dry), and then a stretched polyamide film having a thickness of 25 μm was laminated. Then, it was cured (aged) at 80 ° C. for 2 days to obtain a laminate.

(Examples 2 to 10)
The adhesive was adjusted in the same manner as in Example 1 except that the composition of the adhesive used for laminating the aluminum foil and the unstretched polyolefin film was changed to the composition shown in Tables 1 and 2, to obtain a laminate.

(Comparative Examples 1 to 5)
The adhesive was adjusted in the same manner as in Example 1 except that the composition of the adhesive used for laminating the aluminum foil and the unstretched polyolefin film was changed to the composition shown in Table 3, to obtain a laminate.

The details of the compounds used in Examples and Comparative Examples are as follows.
Toyo Tuck PMA-L: Maleic anhydride-modified olefin resin, acid value: 35 mgKOH / g, melting point: 70 ° C., Toyo Tuck PMA-KE: maleic anhydride modified olefin resin, acid value: 44 mgKOH / g, melting point: 80 ° C, FTR8120 manufactured by Toyo Boseki, styrene resin, EPICRON B-570-H manufactured by Mitsui Chemicals, methyltetrahydrophthalic anhydride, YH-306 manufactured by DIC: trialkyltetrahydrophthalic anhydride, Deconal EX-produced by Mitsubishi Chemicals. 3211: Trimethylol propanepolyglycidyl ether type epoxy resin, Nagase ChemteX EPICLON 860: Bisphenol A type epoxy resin, DIC EPICLON N-665: Cresol novolac type epoxy resin, DIC

The acid value of the olefin resin is a coefficient (f) obtained from a calibration curve prepared by using FT-IR (FT-IR4200 manufactured by Nippon Kogaku Co., Ltd.) and a chloroform solution of maleic anhydride, and a maleic anhydride-modified polyolefin solution. It is a value calculated by the following formula using the absorbance (I) of the expansion and contraction peak (1780 cm ^-1 ) of the anhydrous ring of maleic anhydride and the absorbance (II) of the expansion and contraction peak (1720 cm ^-1 ) of the carbonyl group of maleic anhydride. .. In the following formula, the molecular weight of maleic anhydride was 98.06, and the molecular weight of potassium hydroxide was 56.11.

(Measurement of initial adhesive strength)
Using "Autograph AGS-J" manufactured by Shimadzu Corporation, the adhesive strength at the interface between the aluminum foil of the laminate and the unstretched polyolefin film is set under the conditions of a peeling speed of 50 mm / min, a peeling width of 15 mm, and a peeling form of T type. evaluated.

(Heat-resistant)
Even if an attempt is made to measure the adhesive strength of the laminate after heat sealing, the polyolefin film may be damaged and peeled off not between the polyolefin film and the aluminum foil but between the heat-sealed polyolefin films. The evaluation of heat resistance by comparing the adhesive strength before and after heat sealing is not always accurate. Therefore, the heat resistance was evaluated as follows.

The unstretched polyolefin film side of the laminate was valley-folded, and the unstretched polyolefin film sides were subjected to a heat seal bar at 190 ° C. for 3 seconds. Next, using "Autograph AGS-J" manufactured by Shimadzu Corporation, the interface when peeled by 1 cm under the conditions of a peeling speed of 500 mm / min, a peeling width of 15 mm, and a peeling form T type was evaluated.
⊚: Peeling between unstretched polyolefin film / unstretched polyolefin film is 90% or more (particularly excellent in practical use).
◯: Peeling between the unstretched polyolefin film / unstretched polyolefin film is 60% or more and less than 90% (excellent in practical use).
Δ: Peeling between the unstretched polyolefin film / unstretched polyolefin film is 50% or more and less than 60% (practical range)
X: Detachment between unstretched polyolefin film / unstretched polyolefin film is less than 50%

As is clear from Tables 1 to 3, the adhesive of the present invention is superior in heat resistance to the adhesive of the comparative example.

The adhesive of the present invention is excellent in adhesiveness and heat resistance between a non-polar base material such as an olefin resin and a metal base material, and the laminate obtained by using the adhesive of the present invention can be used as a packaging material for batteries, for example. It can be preferably used. Further, the use of the adhesive of the present invention is not limited to the packaging material for batteries and the laminate for that purpose, and the adhesiveness between a non-polar base material such as a home appliance outer panel, a furniture material, and a building interior member and a metal base material. Is widely available in fields where

Claims (9)

It contains an olefin resin (A), a curing agent (B) containing an epoxy compound, and an acid anhydride (C), and the blending amount of the acid anhydride (C) is 0. With respect to 100 parts by mass of the olefin resin (A). 05 parts by mass or more 10 parts by der less is, der Ru adhesive than 1 part by mass or more 0.01 part by mass relative to the amount said olefin resin (a) 100 parts by mass of the curing agent (B). The acid anhydride (C) contains at least one selected from the group consisting of acid anhydrides and glycol modified products of acid anhydrides, and the acid anhydrides are phthalic anhydrides, trimellitic anhydrides, and pyromerits. Acid anhydride, benzophenone tetracarboxylic acid anhydride, dodecenyl succinic anhydride, polyazipic acid anhydride, polyazereic acid anhydride, polysevacinic acid anhydride, poly (ethyloctadecanedioic acid) anhydride, poly (phenylhexadecanedioic acid) anhydride , Tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, methylhymic anhydride, trialkyltetrahydrophthalic anhydride, methylcyclohexendicarboxylic acid anhydride Methylcyclohexenetetracarboxylic acid anhydride, ethylene glycol bistrimeritate dianhydride, het acid anhydride, nadic acid anhydride, methylnadic acid anhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-Methyl-3-cyclohexane-1,2-dicarboxylic acid anhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic anhydride, 1-methyl-dicarboxy The adhesive according to claim 1, which is at least one selected from the group consisting of -1,2,3,4-tetrahydro-1-naphthalene succinic anhydride. The adhesive according to claim 1 or 2, wherein the olefin resin (A) has an acid group or a hydroxyl group. Any of claims 1 to 3 , which comprises at least one adhesion promoter selected from the group consisting of imidazole compounds, tertiary amines, salts of tertiary amines, cationic catalysts, and organic phosphine compounds. The adhesive according to item 1. Olefin resin (A), the curing agent comprising the epoxy compound (B), see-containing acid anhydride (C), wherein the olefin resin (A) the curing agent per 100 parts by mass of (B) is 0.01 part by weight A premixture for an adhesive blended in an amount of 1 part by mass or less, which contains the olefin resin (A) and the acid anhydride (C), and the content of the acid anhydride (C) is the olefin resin. (A) A premixture of 0.05 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass. A first base material, a second base material, and an adhesive layer for adhering the first base material and the second base material are included, and the adhesive layer is any one of claims 1 to 4. A laminate characterized by being a cured coating film of the adhesive according to the item. Polyolefin film and
With resin film
A metal foil arranged between the polyolefin film and the resin film,
Includes an adhesive layer disposed between the polyolefin film and the metal foil.
A packaging material for a battery, wherein the adhesive layer is a cured coating film of the adhesive according to any one of claims 1 to 4 . A battery container obtained by molding the battery packaging material according to claim 7 . A battery using the battery container according to claim 8 .