Adhesive, adhesive for battery packaging material, laminate, battery packaging material, battery container and battery

Abstract

The present invention provides a reactive adhesive having excellent moldability and heat resistance, a laminate obtained using the adhesive, and a battery packaging material. A two-component solvent-based adhesive, comprising a polyol composition (A) and a polyisocyanate composition (B), wherein the polyisocyanate composition (B) comprises a carbamate prepolymer (B1), wherein the carbamate prepolymer (B1) is a reaction product of a polyester polyol (B1') and a polyisocyanate composition (B1") comprising an aromatic polyisocyanate, wherein the polyester polyol (B1') is a reaction product of a polyol (a) and a polycarboxylic acid (b), wherein 50% by mass or more of the polyol (a) is an aliphatic diol (a1) having 4 to 10 carbon atoms, and 60% by mass or more of the polycarboxylic acid (b) is an aromatic polycarboxylic acid (b1).

Description

Technical Field

[0001] The present invention relates to an adhesive, in particular a reactive adhesive suitable for forming a battery container or battery pack for a lithium ion battery or the like, a laminated body obtained by using the same, a battery packaging material, a battery container and a battery. Background Art

[0002] Due to the rapid spread of electronic devices such as mobile phones and portable computers, the demand for various types of batteries such as lithium ion batteries is increasing. These batteries use packaging materials to seal electronic components such as electrodes and electrolytes, and metal cans (metal cans) are often used as packaging materials.

[0003] On the other hand, in recent years, with the high performance of electric vehicles, hybrid electric vehicles and other vehicles, home storage batteries, computers, cameras, mobile phones, etc., various shapes of batteries are required, and thinning and light weight are required. However, metal can battery packaging materials are difficult to cope with the diversification of shapes, and there is a limit to lightweighting. Therefore, as a battery packaging material that is easy to process into a variety of shapes and can achieve thinning and light weight, a film-like laminated body having an outer side substrate layer, an adhesive layer, a metal layer, and a sealing layer laminated in sequence is proposed.

[0004] In order to form a battery container or a battery pack, a battery packaging material formed of these film-like laminates is sometimes molded so that the outer layer side substrate layer side has a convex surface and the sealant layer side has a concave surface.

[0005] In the battery packaging material, the outer layer side base layer is the outer layer and the sealant layer is the inner layer. When assembling the battery, the sealant layers located at the periphery of the battery element are heat-fused to seal the battery element, thereby sealing the battery element.

[0006] Among them, secondary batteries for vehicle and home storage are installed outdoors and are required to have a long service life. It is required that the adhesion between the layers of the packaging materials such as plastic films and metal foils be maintained for a long time even in an open air environment, and that the appearance be normal.

[0007] In order to improve the properties of these film-shaped battery packaging materials, various studies focusing on adhesive layers for bonding plastic films and metal layers have been conducted.

[0008] For example, Patent Document 1 discloses that in a laminated packaging material comprising an inner layer including a resin film, a first adhesive layer, a metal layer, a second adhesive layer, and an outer layer including a resin film, at least one of the first adhesive layer and the second adhesive layer is formed from an adhesive composition comprising a resin having an active hydrogen group in a side chain, a polyfunctional isocyanate, and a polyfunctional amine compound, thereby obtaining a packaging material with high reliability for deeper molding.

[0009] In addition, Patent Document 2 discloses that the following adhesive is used as the outer adhesive layer of a battery packaging material having an outer resin film layer, an outer adhesive layer, a metal foil layer, an inner adhesive layer, and a heat seal layer: an acrylic polyol (A) having a number average molecular weight of 10,000 to 100,000 and a hydroxyl value of 1 to 100 mgKOH / g and an isocyanate curing agent, and an adhesive in which the equivalent ratio [NCO] / [OH] of the isocyanate group derived from the aromatic polyisocyanate (B) contained in the curing agent to the hydroxyl group derived from the acrylic polyol (A) is 10 to 30. This can provide a battery packaging material having excellent moldability, no decrease in interlayer bonding strength even after a long-term durability test, and no appearance defects such as floating between layers.

[0010] In addition, Patent Document 3 discloses that as an outer side adhesive layer having the same structure as Patent Document 2, the following adhesive is used: a polyol component (A) and an isocyanate curing agent are used, and the equivalent ratio [NCO] / ([OH]+[COOH]) of the isocyanate group contained in the curing agent to the total of the hydroxyl group and the carboxyl group derived from the polyol (A) is 0.5 to 10, thereby obtaining an adhesive having excellent moldability and being durable even under high temperature and high humidity conditions of 105°C, 100% RH, and 168 hours. A battery packaging material having poor appearance such as no reduction in interlayer bonding strength and no floating between layers after a durability test, wherein the polyol component (A) contains 85 to 99% by weight of a polyester polyol (A1) and 1 to 15% by weight of a trifunctional or higher alcohol component (A2), wherein the polyester polyol (A1) is a polyester polyol having a number average molecular weight of 5,000 to 50,000 and is composed of a polyacid component and a polyol component, and 100% by mole of the polyacid component contains 45 to 95% by mole of an aromatic polyacid component.

[0011] Prior art literature

[0012] Patent Literature

[0013] Patent Document 1: Japanese Patent Application Publication No. 2008-287971

[0014] Patent Document 2: Japanese Patent Application Publication No. 2014-185317

[0015] Patent Document 3: Japanese Patent Application Publication No. 2015-82354 Summary of the invention

[0016] Problem that the invention aims to solve

[0017] An object of the present invention is to provide a reactive adhesive having excellent moldability and heat resistance, which is suitable for the production of a battery packaging material, and a laminate and a battery packaging material obtained by using the adhesive.

[0018] Solutions for solving problems

[0019] The present invention relates to a two-component solvent-based adhesive, comprising a polyol composition (A) and a polyisocyanate composition (B), wherein the polyisocyanate composition (B) comprises a urethane prepolymer (B1), wherein the urethane prepolymer (B1) is a reaction product of a polyester polyol (B1') and a polyisocyanate composition (B1") comprising an aromatic polyisocyanate, wherein the polyester polyol (B1') is a reaction product of a polyol (a) and a polycarboxylic acid (b), wherein 50% by mass or more of the polyol (a) is an aliphatic diol (a1) having 4 to 10 carbon atoms, and 60% by mass or more of the polycarboxylic acid (b) is an aromatic polycarboxylic acid (b1).

[0020] The present invention also relates to a laminated body obtained by bonding a plurality of substrates together using the above-mentioned two-component solvent-based adhesive.

[0021] The present invention also relates to a battery packaging material comprising at least an outer substrate layer 1, an adhesive layer 2, a metal layer 3 and a sealant layer 4 laminated in this order, wherein the adhesive layer 2 is a cured product of the two-component solvent-based adhesive.

[0022] Furthermore, the present invention relates to a battery container obtained by molding the above-described battery packaging material.

[0023] Furthermore, the present invention relates to a battery using the above-described battery container.

[0024] Effects of the Invention

[0025] By using the adhesive of the present invention, a battery packaging material having excellent moldability and heat resistance and suitable for sealing battery elements can be obtained. A battery container using the battery packaging material of the present invention can provide a battery with excellent reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is an example of a specific embodiment of a laminated body in which an outer-layer-side base material layer 1, an adhesive layer 2, a metal layer 3, and a sealant layer 4 are laminated in this order according to the present invention.

[0027] Figure 2 This is an example of a specific form of a laminate in which an outer layer side base material layer 1, an adhesive layer 2, a metal layer 3, an adhesive layer 5, and a sealing layer 4 are sequentially laminated in the present invention. Specific Embodiment

[0028] <Adhesive>

[0029] The adhesive of the present invention is a two-component solvent-based adhesive, which contains a polyol composition (A) and a polyisocyanate composition (B). The polyisocyanate composition (B) contains a urethane prepolymer (B1). The urethane prepolymer (B1) is a reaction product of a polyester polyol and a polyisocyanate composition containing an aromatic polyisocyanate. The polyester polyol is a reaction product of a polyol and a polycarboxylic acid. More than 50% by mass of the polyol is an aliphatic diol having 4 to 10 carbon atoms, and more than 60% by mass of the polycarboxylic acid is an aromatic polycarboxylic acid. The adhesive of the present invention will be described in detail below.

[0030] (Polyol Composition (A))

[0031] (Polyester Polyol (A1))

[0032] The polyol composition (A) used in the adhesive of the present invention includes polyol compounds such as polyether polyol, polyester polyol, and polycarbonate polyol. Among them, a polyester polyol (A1) containing a polyacid or its derivative and a polyol as essential raw materials is preferably included.

[0033] Examples of the polyacid or its derivative used as a raw material for the polyester polyol (A1) include aliphatic polyacids such as malonic acid, ethylmalonic acid, dimethylmalonic acid, succinic acid, 2,2-dimethylsuccinic acid, succinic anhydride, alkenyl succinic anhydride, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, fumaric acid, maleic acid, maleic anhydride, and itaconic acid;

[0034] alkyl esters of aliphatic polyacids such as dimethyl malonate, diethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, diethyl pimelate, diethyl sebacate, dimethyl fumarate, diethyl fumarate, dimethyl maleate, and diethyl maleate;

[0035] alicyclic polyacids such as 1,1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, tetrahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride, nadic anhydride, and chlorendic anhydride;

[0036] Aromatic polyacids such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride, 1,4-naphthalene dicarboxylic acid, 2,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 2,3-naphthalene dicarboxylic anhydride, naphthalene dicarboxylic acid, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, biphenyl dicarboxylic acid, 1,2-bis(phenoxy)ethane-p,p'-dicarboxylic acid, benzophenone tetracarboxylic acid, benzophenone tetracarboxylic dianhydride, 5-sodium sulfoisophthalate, tetrachlorophthalic anhydride, and tetrabromophthalic anhydride;

[0037] Methyl esters of aromatic polybasic acids such as dimethyl terephthalate and dimethyl 2,6-naphthalenedicarboxylate can be used alone or in combination of two or more.

[0038] The polyol may be a diol or a trifunctional or higher polyol. Examples of the diol include ethylene glycol, diethylene glycol, propylene glycol, 1,3-propylene glycol, 1,2,2-trimethyl-1,3-propylene glycol, 2,2-dimethyl-3-isopropyl-1,3-propylene glycol, 1,4-butanediol, 1,3-butanediol, 3-methyl-1,3-butanediol, 1,5-pentanediol, 1-methyl-1,5-pentanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, aliphatic diols such as neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, 2-methyl-1,7-heptanediol, 3-methyl-1,7-heptanediol, 4-methyl-1,7-heptanediol, 1,9-nonanediol, 1,11-undecanediol, 1,13-tridecanediol, 1,15-pentadecandiol, 1,17-heptadecandiol, 1,19-nonadecandiol, 1,4-bis(hydroxymethyl)cyclohexane, and 2,2,4-trimethyl-1,3-pentanediol;

[0039] Ether diols such as polyoxyethylene glycol and polyoxypropylene glycol;

[0040] Modified polyether diols obtained by ring-opening polymerization of the aliphatic diols with various cyclic ether bond-containing compounds such as ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, propyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, and allyl glycidyl ether;

[0041] Lactone polyester polyols obtained by polycondensation of the aliphatic diols with lactide (Japanese: ラクタノイド), ε-caprolactone and other lactones;

[0042] Bisphenols such as bisphenol A and bisphenol F;

[0043] Alkylene oxide adducts of bisphenols obtained by adding ethylene oxide, propylene oxide, etc. to bisphenols such as bisphenol A and bisphenol F, and the like.

[0044] Examples of trifunctional or higher polyols include aliphatic polyols such as trimethylolethane, trimethylolpropane, glycerol, hexanetriol, and pentaerythritol;

[0045] Modified polyether polyols obtained by ring-opening polymerization of the aliphatic polyols with various cyclic ether bond-containing compounds such as ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, propyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, and allyl glycidyl ether;

[0046] Lactone polyester polyols obtained by polycondensation of the above-mentioned aliphatic polyols with various lactones such as ε-caprolactone, etc.

[0047] In the present invention, from the viewpoint of improving the appearance of the laminate, it is preferred that the polyol contain a branched alkylene glycol.

[0048] Specifically, the branched alkylene glycol is an alkylene glycol having a tertiary carbon atom or a quaternary carbon atom in its molecular structure, and examples thereof include 1,2,2-trimethyl-1,3-propanediol, 2,2-dimethyl-3-isopropyl-1,3-propanediol, 3-methyl-1,3-butanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,4-bis(hydroxymethyl)cyclohexane, 2,2,4-trimethyl-1,3-pentanediol, etc. These can be used alone or in combination of two or more thereof. Among these, neopentyl glycol is preferred from the viewpoint of obtaining a polyester polyol (A1) having excellent moisture and heat resistance.

[0049] In the present invention, the polyester polyol (A1) may be a polyester polyurethane polyol having polyacids or derivatives thereof, polyols, and polyisocyanates as essential raw materials. The polyisocyanates used in this case may include diisocyanate compounds and trifunctional or higher polyisocyanate compounds. These polyisocyanates may be used alone or in combination of two or more.

[0050] Examples of the diisocyanate compound include aliphatic diisocyanates such as butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, xylylene diisocyanate, m-tetramethylxylylene diisocyanate, and lysine diisocyanate;

[0051] Alicyclic diisocyanates such as cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanatemethyl)cyclohexane, methylcyclohexane diisocyanate, isopropylidene dicyclohexyl-4,4'-diisocyanate, and norbornane diisocyanate;

[0052] Aromatic diisocyanates such as 1,5-naphthalene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl diisocyanate, dialkyl diphenylmethane diisocyanate, tetraalkyl diphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate and toluene diisocyanate.

[0053] Alternatively, allophanate forms, biuret forms, carbodiimide-modified forms, and the like of these diisocyanate compounds may also be used.

[0054] Examples of the trifunctional or higher-functional polyisocyanate compound include an addition-type polyisocyanate compound having a urethane bond site in the molecule and a ureate-type polyisocyanate compound having an isocyanurate ring structure in the molecule.

[0055] The addition type polyisocyanate compound having a carbamate bond site in the molecule is obtained, for example, by reacting a diisocyanate compound with a polyol. The diisocyanate compound used in the reaction may include the various diisocyanate compounds exemplified above, which may be used alone or in combination of two or more. In addition, the polyol compound used in the reaction may include the various polyol compounds exemplified as the raw materials of the polyester polyol (A1), polyester polyols obtained by reacting a polyol with a polyacid, etc., which may be used alone or in combination of two or more.

[0056] The urate type polyisocyanate compound with isocyanurate ring structure in the molecule is obtained by, for example, reacting a diisocyanate compound with a monohydric alcohol and / or a diol. The diisocyanate compound used in the reaction can enumerate the various diisocyanate compounds exemplified above, and these can be used alone or in combination with two or more. In addition, as the monohydric alcohol used in the reaction, hexanol, 2-ethylhexanol, octanol, n-decanol, n-undecyl alcohol, n-dodecanol, n-tridecanol, n-tetradecanol, n-pentadecanol, n-heptadecanol, n-octadecanol, n-nonadecanol, eicosanol, 5-ethyl-2-nonanol, trimethyl nonanol, 2-hexyldecanol, 3,9-diethyl-6-tridecanol, 2-isoheptyl isoundecanol, 2-octyldodecyl alcohol, 2-decyltetradecanol, etc. can be enumerated, and as diols, aliphatic diols exemplified as the raw materials of polyester polyol (A1) can be enumerated. These monohydric alcohols and diols may be used alone or in combination of two or more.

[0057] The polyester polyol (A1) is preferably a reaction product of a polyacid or its derivative and a polyol, and the ratio of the polyacid or its derivative having an aromatic ring in the polyacid or its derivative is 30 mol% or more. Thus, an adhesive having excellent storage stability can be prepared. Furthermore, from the aspect of improved formability and heat resistance, the ratio of the polyacid or its derivative having an aromatic ring in the polyacid or its derivative is more preferably 50 mol% or more, more preferably 70 mol% or more, and more preferably 96 mol% or more. All of the polyacid or its derivative may be a polyacid having an aromatic ring.

[0058] Alternatively, the polyester polyol (A1) may also be a reaction product of a polyacid or its derivatives with a polyol and a polyisocyanate, and the ratio of the polyacid or its derivatives having an aromatic ring in the polyacid or its derivatives is preferably 30 mol% or more. Thus, an adhesive having excellent storage stability can be prepared. Furthermore, from the aspect of improved formability and heat resistance, the ratio of the polyacid or its derivatives having an aromatic ring in the polyacid or its derivatives is more preferably 50 mol% or more, more preferably 70 mol% or more, and more preferably 96 mol% or more. All of the polyacid or its derivatives may be polyacids having aromatic rings.

[0059] The hydroxyl value of the polyester polyol (A1) is preferably in the range of 1 to 40 mgKOH / g, and more preferably 3 mgKOH / g or more and 30 mgKOH / g or less, from the viewpoint of more excellent adhesive strength.

[0060] The number average molecular weight (Mn) of the polyester polyol (A1) is preferably in the range of 2,000 to 100,000, more preferably 2,000 to 50,000, from the viewpoint of better adhesive strength when used for adhesive applications. When the number average molecular weight is less than 2,000, the crosslinking density in the cured coating film becomes too high, and the appearance and moldability of the laminate may be poor.

[0061] On the other hand, the weight average molecular weight (Mw) is preferably in the range of 5,000 to 300,000, more preferably in the range of 10,000 to 200,000.

[0062] In addition, in this invention, the weight average molecular weight (Mw) and the number average molecular weight (Mn) are the values ​​measured by gel permeation chromatography (GPC) under the following conditions.

[0063] Measuring device: HLC-8320GPC manufactured by Tosoh Corporation

[0064] Column; TSKgel 4000HXL, TSKgel 3000HXL, TSKgel 2000HXL, TSKgel1000HXL manufactured by Tosoh Corporation

[0065] Detector: RI (differential refractometer)

[0066] Data processing: Multi-station GPC-8020model II manufactured by Tosoh Corporation

[0067] Determination conditions: column temperature 40°C

[0068] Solvent Tetrahydrofuran

[0069] Flow rate 0.35ml / min

[0070] Standard; monodisperse polystyrene

[0071] Sample: A substance obtained by filtering a tetrahydrofuran solution containing 0.2% by mass of the resin solid content using a microfilter (100 μl)

[0072] The solid content acid value of the polyester polyol (A1) is not particularly limited, but is preferably 10.0 mgKOH / g or less. When it is 5.0 mgKOH / g or less, the moisture and heat resistance is more excellent, which is preferred. In addition, there is no particular limitation on the lower limit of the solid content acid value, but as an example, it is 0.5 mgKOH / g or more. It can be 0 mgKOH / g.

[0073] The glass transition temperature of the polyester polyol (A1) is not particularly limited, but is preferably -30°C or higher, more preferably -20°C or higher, in order to suppress adhesive bleeding during dry lamination when producing a laminate. The upper limit is not particularly limited, but is preferably 110°C or lower in consideration of storage stability and productivity.

[0074] The polyester polyol (A1) used in the present invention may include two or more polyester polyols having different glass transition temperatures. In this case, it is preferred to include a polyester polyol (A1-1) having a glass transition temperature of -30°C to 20°C and a polyester polyol (A1-2) having a glass transition temperature of 50°C to 110°C. Thus, heat resistance and moist heat resistance can be improved.

[0075] When the polyester polyol (A1) contains the polyester polyol (A1-1) and the polyester polyol (A1-2), the blending ratio is preferably such that the blending amount of the polyester polyol (A1-1) in the total amount of the polyester polyols (A1-1) and (A1-2) is 50% by mass or more and 99% by mass or less.

[0076] In addition, the glass transition temperature in the present invention refers to a value measured as follows.

[0077] Using a differential scanning calorimeter (DSC-7000 manufactured by SII NanoTechnology Inc., hereinafter referred to as DSC), 5 mg of the sample was heated from room temperature to 200°C at 10°C / min under a nitrogen flow of 30 mL / min, and then cooled to -80°C at 10°C / min. The temperature was again raised to 150°C at 10°C / min to measure the DSC curve, and the intersection of the straight line extending the baseline on the low temperature side of the measurement result observed in the second heating process to the high temperature side and the tangent line drawn at the point where the slope of the curve of the step-shaped part of the glass transition becomes the maximum was taken as the glass transition point, and the temperature at this time was taken as the glass transition temperature. In addition, the temperature was raised to 200°C in the first heating, but it was sufficient as long as it was a temperature at which the polyester polyol (A1) would be fully melted. If it was insufficient at 200°C, it was appropriately adjusted. Similarly, the cooling temperature was also appropriately adjusted if it was insufficient at -80°C (such as when the glass transition temperature was lower).

[0078] The polyester polyol (A1) used in the present invention also preferably includes a polyester polyol (A1-3), which is synthesized using a polyol in which the carbon number of the methylene chain between two hydroxyl groups is 5 or more and 19 or less and is an odd number. It should be noted that the methylene chain can be a straight chain or a branched chain with a side chain. When the methylene chain includes a side chain, the carbon number of the side chain is not included in the carbon number of the methylene chain. Thus, it is possible to make the adhesion, moldability, and heat resistance excellent.

[0079] When the polyester polyol (A1) contains the polyester polyol (A1-3), the amount thereof blended is preferably 1% by mass or more and 50% by mass or less of the polyester polyol (A1).

[0080] In the synthesis of the polyester polyol (A1), the reaction of the polybasic acid or its derivative with the polyol, or the reaction of the polybasic acid or its derivative with the polyol and the polyisocyanate can be carried out by a known method.

[0081] For example, the reaction of the polyacid or its derivative with the polyol can be carried out by a polycondensation reaction. In addition, the reaction of the polyacid or its derivative with the polyol and the polyisocyanate can be carried out by reacting the polyisocyanate with the polyester polyol obtained by reacting the polyacid or its derivative with the polyol by the method described above in the presence of a known and commonly used urethanization catalyst as required to obtain the polyester polyol (A1).

[0082] For the esterification reaction of a polybasic acid or its derivative with a polyol, a polybasic acid or its derivative, a polyol, and a polymerization catalyst are placed in a reaction vessel equipped with a stirrer and a distillation device, and the temperature is raised to about 130° C. under normal pressure while stirring. Thereafter, the generated water is distilled off while the temperature is raised at a rate of 5 to 10° C. per hour at a reaction temperature in the range of 130 to 260° C. After the esterification reaction is carried out for 4 to 12 hours, the excess polyol is distilled off while the degree of reduced pressure is gradually increased from normal pressure to a range of 1 to 300 torr to promote the reaction, thereby producing a polyester polyol (A1).

[0083] As the polymerization catalyst used in the esterification reaction, a polymerization catalyst containing at least one metal selected from Group 2, Group 4, Group 12, Group 13, Group 14, and Group 15 of the periodic table, or a compound of the metal is preferred. Examples of the polymerization catalyst containing the metal or the metal compound include metals such as Ti, Sn, Zn, Al, Zr, Mg, Hf, and Ge, compounds of these metals, more specifically titanium tetraisopropoxide, titanium tetrabutoxide, titanium acetylacetonate, tin octylate, 2-ethylhexyltin, zinc acetylacetonate, zirconium tetrachloride, zirconium tetrachloride tetrahydrofuran complex, hafnium tetrachloride, hafnium tetrachloride tetrahydrofuran complex, germanium oxide, tetraethoxygermanium, and the like.

[0084] Preferred commercially available polymerization catalysts that can be used in the esterification reaction include Orgatix TA series, TC series, ZA series, ZC series, and AL series manufactured by Matsumoto Fine Chemical Co., Ltd., and organotin catalysts, inorganic metal catalysts, and inorganic tin compounds manufactured by Nitto Kasei Co., Ltd.

[0085] The amount of these polymerization catalysts used is not particularly limited as long as the esterification reaction can be controlled and a polyester polyol (A1) of good quality can be obtained. As an example, the amount is 10 to 1,000 ppm, preferably 20 to 800 ppm, relative to the total amount of the polyacid or its derivative and the polyol. In order to suppress the coloration of the polyester polyol (A1), it is more preferably 30 to 500 ppm.

[0086] In addition, the polyester polyurethane polyol is obtained by chain-extending the polyester polyol obtained by the above method using a polyisocyanate. As a specific production method, a polyester polyol, a polyisocyanate, a chain-extending catalyst, and a good solvent for the polyester polyol and the polyisocyanate used as needed are put into a reaction container and stirred at a reaction temperature of 60 to 90° C. The reaction is carried out until the isocyanate group derived from the polyisocyanate used is substantially eliminated, thereby obtaining the polyester polyurethane polyol used in the present invention.

[0087] As the chain extension catalyst, a known and commonly used catalyst used as a common urethanization catalyst can be used. Specifically, organic tin compounds, organic carboxylic acid tin salts, lead carboxylates, bismuth carboxylates, titanium compounds, zirconium compounds, etc. can be cited, which can be used alone or in combination. The amount of the chain extension catalyst used is sufficient to promote the reaction of the polyester polyol and the polyisocyanate. Specifically, it is preferably 5.0% by mass or less relative to the total amount of the polyester polyol and the polyisocyanate. In order to inhibit the hydrolysis and coloring of the resin by the catalyst, it is more preferably 1.0% by mass or less. Furthermore, these chain extension catalysts can be used as curing catalysts for the polyol composition (A) and the isocyanate composition (B) described later.

[0088] The method for confirming the residual amount of isocyanate groups is as follows: measuring the residual amount of isocyanate groups by infrared absorption spectroscopy at 2260 cm-1, which is an absorption spectrum derived from isocyanate groups. -1 Confirmation of the presence or absence of an absorption peak observed nearby and quantification of isocyanate groups by titration.

[0089] Examples of good solvents used in the production of polyester polyurethane polyol include acetone, methyl acetate, ethyl acetate, butyl acetate, dimethyl carbonate, methyl ethyl ketone, methyl isobutyl ketone, propylene glycol monomethyl ether acetate, toluene, xylene, etc. These solvents may be used alone or in combination of two or more.

[0090] (Polyol (A2))

[0091] The polyol composition (A) may contain a polyol (A2) other than the polyester polyol (A1) within a range not impairing the effects of the present invention. Examples of the polyol (A2) include polycarbonate polyols and polyether polyols.

[0092] The number average molecular weight (Mn) of the polycarbonate polyol is preferably in the range of 300 to 2,000 from the perspective of forming an adhesive having high adhesion to various substrates and excellent moisture and heat resistance. The hydroxyl value is preferably in the range of 30 to 250 mgKOH / g, and more preferably in the range of 40 to 200 mgKOH / g. In addition, the polycarbonate polyol is preferably a polycarbonate diol. From the perspective of forming an adhesive having high adhesion to various substrates and excellent moisture and heat resistance, the total amount of the polyester polyol (A1) and the blending ratio of the polycarbonate polyol are preferably 30% by mass or more, and more preferably 60% by mass or more, relative to the total mass of the two.

[0093] The number average molecular weight (Mn) of the polyether polyol is preferably in the range of 300 to 2,000 from the perspective of an adhesive having high adhesion to various substrates and excellent moisture and heat resistance. The hydroxyl value is preferably in the range of 40 to 250 mgKOH / g, and more preferably in the range of 50 to 200 mgKOH / g. In addition, the polyether polyol compound is preferably a polyether diol. With respect to the total amount of the polyester polyol (A1) and the blending ratio of the polyether polyol, from the perspective of an adhesive having high adhesion to various substrates and excellent moisture and heat resistance, the total mass of the polyester polyol (A1) is preferably 30% by mass or more, and more preferably 60% by mass or more, relative to the total mass of the two.

[0094] (Other resins (A3))

[0095] The polyol composition (A) may contain a resin (A3) other than polyester polyol (A1) and polyol (A2). When using resin (A3), it is preferably used at 50% by mass or less, preferably at 30% by mass or less relative to the total mass of the solid content of the polyol composition (A). As a specific example of resin (A3), epoxy resins may be cited. Epoxy resins include, for example, bisphenol-type epoxy resins such as bisphenol A epoxy resin and bisphenol F epoxy resin; biphenyl-type epoxy resins such as biphenyl-type epoxy resin and tetramethylbiphenyl-type epoxy resin; dicyclopentadiene-phenol addition reaction type epoxy resins, etc. These may be used alone or in combination of two or more. Among these, bisphenol-type epoxy resins are preferably used from the perspective of being an adhesive having high adhesion to various substrates and excellent moisture and heat resistance.

[0096] The number average molecular weight (Mn) of the epoxy resin is preferably in the range of 300 to 2,000 from the viewpoint of providing an adhesive having high adhesion to various substrates and excellent moisture and heat resistance. The epoxy equivalent is preferably in the range of 150 to 1,000 g / equivalent.

[0097] When an epoxy resin is used, the total amount of the polyester polyol (A1) and the blending ratio of the epoxy resin are such that the total mass of the polyester polyol (A1) is preferably in the range of 30 to 99.5 mass %, more preferably in the range of 60 to 99 mass %, relative to the total mass of the two, from the perspective of obtaining an adhesive having high adhesion to various substrates and excellent moisture and heat resistance.

[0098] (Thickener)

[0099] The polyol composition (A) may contain a tackifier. As the tackifier, for example, rosin or rosin ester tackifiers, terpene or terpene phenol tackifiers, saturated hydrocarbon resins, coumarone tackifiers, coumarone indene tackifiers, styrene resin tackifiers, xylene resin tackifiers, phenolic resin tackifiers, petroleum resin tackifiers, ketone resin tackifiers, etc. are mentioned. Ketone resin tackifiers, rosin or rosin ester tackifiers, and more preferably ketone resin tackifiers are preferred. These can be used alone or in combination of two or more. When a tackifier is used, the total mass of the polyester polyol (A1) is preferably 80 to 99.99% by mass, more preferably 85 to 99.9% by mass, relative to the total mass of the polyester polyol (A1) and the tackifier.

[0100] Examples of rosin or rosin esters include polymerized rosin, disproportionated rosin, hydrogenated rosin, maleated rosin, fumarated rosin, and glycerol esters, pentaerythritol esters, methyl esters, ethyl esters, butyl esters, ethylene glycol esters, diethylene glycol esters, and triethylene glycol esters thereof.

[0101] Examples of the terpene-based or terpene-phenol-based compounds include oligomeric terpene-based compounds, α-pinene polymers, β-pinene polymers, terpene-phenol-based compounds, aromatic modified terpene-based compounds, and hydrogenated terpene-based compounds.

[0102] Examples of the petroleum resin system include petroleum resins obtained by polymerizing petroleum fractions with a carbon number of 5 obtained from pentene, pentadiene, isoprene, etc., petroleum resins obtained by polymerizing petroleum fractions with a carbon number of 9 obtained from indene, methylindene, vinyltoluene, styrene, α-methylstyrene, β-methylstyrene, etc., C5-C9 copolymer petroleum resins obtained from the above-mentioned various monomers and petroleum resins obtained by hydrogenating them, petroleum resins obtained from cyclopentadiene and dicyclopentadiene; and hydrogenated products of these petroleum resins; modified petroleum resins obtained by modifying these petroleum resins with maleic anhydride, maleic acid, fumaric acid, (meth)acrylic acid, phenol, etc., etc.

[0103] As the phenolic resin system, a condensate of phenols and formaldehyde can be used. As the phenols, phenol, meta-cresol, 3,5-xylenol, p-alkylphenol, resorcinol, etc. can be cited, and examples thereof include resols obtained by making these phenols and formaldehyde undergo addition reaction using a base catalyst, and novolacs obtained by undergoing condensation reaction using an acid catalyst. In addition, rosin phenolic resins obtained by adding phenol to rosin using an acid catalyst and performing thermal polymerization can also be illustrated.

[0104] Examples of the ketone resin include known and commonly used ketone resins, and formaldehyde resins, cyclohexanone-formaldehyde resins, and ketone-aldehyde condensation resins can be preferably used.

[0105] Tackifiers having various softening points are available, but from the viewpoints of compatibility when mixed with other resins constituting the polyol composition (A), color tone, thermal stability, etc., ketone resin-based tackifiers having a softening point of 70 to 160° C., preferably 80 to 100° C., or rosin-based resins and hydrogenated derivatives thereof having a softening point of 80 to 160° C., preferably 90 to 110° C. are preferred, and ketone resin-based tackifiers having a softening point of 70 to 160° C., preferably 80 to 100° C. are more preferred. Ketone resin-based tackifiers having an acid value of 2 to 20 mgKOH / g and a hydroxyl value of 10 mgKOH / g or less and hydrogenated rosin-based tackifiers are also preferred, and ketone-based tackifiers having an acid value of 2 to 20 mgKOH / g and a hydroxyl value of 10 mgKOH / g or less are more preferred.

[0106] (Polyisocyanate composition (B))

[0107] (Urethane prepolymer (B1))

[0108] The polyisocyanate composition (B) used in the present invention contains a urethane prepolymer (B1), wherein the urethane prepolymer (B1) is a reaction product of a polyester polyol (B1') and a polyisocyanate composition (B1") containing an aromatic polyisocyanate, wherein the polyester polyol (B1') is a reaction product of a polyol (a) and a polycarboxylic acid (b). In addition, 50% by mass or more of the polyol (a) is an aliphatic diol (a1) having 4 to 10 carbon atoms in a methylene chain between two hydroxyl groups, and 60% by mass or more of the polycarboxylic acid (b) is an aromatic polycarboxylic acid (b1). Thus, an adhesive having excellent heat resistance and moldability can be prepared. It should be noted that the methylene chain of the aliphatic diol (a1) may be a straight chain or a branched chain having a side chain. When the methylene chain includes a side chain, the number of carbon atoms of the side chain is not included in the number of carbon atoms of the methylene chain.

[0109] Examples of the aliphatic diol (a1) include 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2,5-dimethyl-2,5-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol.

[0110] The polyol (a) may be entirely aliphatic diol (a1) or may contain a polyol other than aliphatic diol (a1). As the polyol that can be used in combination with aliphatic diol (a1), the same ones as those exemplified as the raw materials of polyester polyol (A1) can be used.

[0111] In one embodiment of the present invention, the polyol preferably includes a trifunctional or higher polyol (a2). As the polyol (a2), the trifunctional or higher polyols exemplified as the raw materials of the polyester polyol (A1) can be exemplified. Glycerol and trimethylolpropane are preferred. When the polyol (a) includes a trifunctional or higher polyol (a2), the blending amount thereof is preferably 0.1 to 20% by mass of the polyol (a).

[0112] As the aromatic polycarboxylic acid (b1), the same substances as those exemplified as the raw materials of the polyester polyol (A1) can be used. Phthalic acid or its derivatives are preferably used. The amount of phthalic acid or its derivatives in the aromatic polycarboxylic acid (b1) is preferably 30% by mass or more, more preferably 50% by mass or more, more preferably 80% by mass or more. All of the aromatic polycarboxylic acid (b1) can be phthalic acid or its derivatives.

[0113] The number average molecular weight (Mn) of the polyester polyol (B1′) can be appropriately adjusted, and as an example, is 500 or more and 10,000 or less.

[0114] The polyisocyanate composition (B1") contains an aromatic polyisocyanate as an essential component. In addition, the polyisocyanate composition (B1") may contain polyisocyanates other than aromatic polyisocyanates. As the aromatic polyisocyanate and the polyisocyanate in which the aromatic polyisocyanate can be used in combination, the same substances as those exemplified as the raw materials of the polyester polyol (A1) can be used. As the aromatic polyisocyanate, it is preferred to use at least one of 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, and adducts of these diphenylmethane diisocyanates and low molecular weight polyols, such as trimethylolpropane.

[0115] The content of the aromatic polyisocyanate in the polyisocyanate composition (B1") is preferably 30% by mass or more, more preferably 50% by mass or more.

[0116] The urethane prepolymer (B1) may be a urethane prepolymer (B1) which is a reaction product of a polyester polyol (B1'), a polyisocyanate composition (B1") containing an aromatic polyisocyanate, and a polyol (B1'"). In one embodiment of the present invention, the polyol (B1'") is preferably a trifunctional or higher polyol (B1'"-1). As the trifunctional or higher polyol (B1'"-1), the trifunctional or higher polyols exemplified as raw materials for the polyester polyol (A1) may be mentioned. Glycerin and trimethylolpropane are preferred.

[0117] When a trifunctional or higher-functional polyol (B1"'-1) is used for the synthesis of the urethane prepolymer (B1), the blending amount thereof is preferably 0.1 to 10% by mass based on the total amount of the polyester polyol (B1').

[0118] In one embodiment of the present invention, the polyol (B1"') is preferably at least one selected from polyester polyol (B1"'-2) and polyether polyol (B1"'-3) other than polyester polyol (B1"'). As the raw material of the polyester polyol (B1"'-2), the polyacid or its derivatives and polyols exemplified as the raw materials of the polyester polyol (A1) can be suitably used.

[0119] As the polyether polyol (B1"'-3), those exemplified as the raw materials of the polyester polyol (A1) can be suitably used. The number average molecular weight and the hydroxyl value may be the same as those of the polyol (A2).

[0120] When at least one of the polyols (B1"'-2) and (B1"'-3) is used in the synthesis of the urethane prepolymer (B1), the amount thereof blended is preferably 10 to 90% by mass of the total amount of the polyester polyol (B1').

[0121] The urethane prepolymer (B1) is obtained by reacting a polyester polyol (B1') with a polyisocyanate composition (B1") under the condition that the isocyanate groups contained in the polyisocyanate composition (B1") are in excess relative to the hydroxyl groups possessed by the polyester polyol (B1'). When the number of moles of the hydroxyl groups possessed by the polyester polyol (B1') is set to [OH] and the number of moles of the isocyanate groups contained in the polyisocyanate composition (B1") is set to [NCO], it is preferred to react under the condition that [NCO] / [OH] is 1.5 to 20.

[0122] The amount of the urethane prepolymer (B1) in the solid content of the polyisocyanate composition (B) can be appropriately adjusted so that the preferred blending ratio of the polyol composition (A) and the polyisocyanate composition (B) described later is achieved and the NCO% of the polyisocyanate composition (B) is within an appropriate range. As an example, it is preferably 10% by mass or more, more preferably 30% by mass or more, and more preferably 80% by mass or more.

[0123] (Polyisocyanate compound (B2))

[0124] The polyisocyanate composition (B) used in the present invention also preferably contains trifunctional or more aromatic polyisocyanates (B2). Thus, an adhesive having excellent heat seal resistance can be prepared. As the polyisocyanate compound (B2), adducts, ureate bodies, biuret bodies, carbodiimide bodies, and oligomers of aromatic diisocyanates can be cited. As aromatic diisocyanates, the same substances as those exemplified as raw materials of polyester polyol (A1) can be used.

[0125] When the polyisocyanate composition (B) contains the polyisocyanate compound (B2), the amount thereof blended is preferably 5% by mass or more, more preferably 10% by mass or more, based on the total amount of the polyisocyanate composition (B).

[0126] (Polyisocyanate compound (B3))

[0127] The polyisocyanate composition (B) used in the present invention may contain polyisocyanate compounds (B3) other than the urethane prepolymer (B1) and the polyisocyanate compound (B2). As the polyisocyanate compound (B3), the same substances as those exemplified as the raw materials of the polyester polyol (A1) can be used. The compounding amount of the polyisocyanate compound (B3) is preferably limited to less than 50% by mass of the polyisocyanate composition (B).

[0128] The polyisocyanate composition (B) is preferably adjusted to have an NCO% of 2% to 30%. This can provide an adhesive having an excellent balance among adhesiveness, heat resistance, and moldability.

[0129] (Organic Solvent)

[0130] The adhesive of the present invention is used in the form of a solvent-based adhesive. It should be noted that the "solvent-based" adhesive referred to in the present invention refers to a method in which the adhesive is applied to a substrate, heated in an oven, etc. to volatilize the organic solvent in the coating film, and then bonded to other substrates, or a form used in the so-called dry lamination method. Either or both of the polyol composition (A) and the polyisocyanate composition (B) contain a highly soluble organic solvent that can dissolve the polyol composition (A) or the polyisocyanate composition (B) used in the present invention. The organic solvent used as a reaction medium when manufacturing the constituent components of the polyol composition (A) or the polyisocyanate composition (B) is sometimes also used as a diluent during coating. Examples of highly soluble organic solvents include esters such as methyl acetate, ethyl acetate, butyl acetate, dimethyl carbonate, and cellosolve acetate; ketones such as acetone, methyl ethyl ketone, isobutyl ketone, and cyclohexanone; ethers such as tetrahydrofuran and dioxane; aromatic hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as dichloromethane and dichloroethane; dimethyl sulfoxide; and dimethylsulfonamide.

[0131] (Other adhesive ingredients)

[0132] The adhesive of the present invention may contain components other than those mentioned above. These components may be added in advance to either or both of the polyol composition (A) and the polyisocyanate composition (B), or may be added when the polyol composition (A) and the polyisocyanate composition (B) are mixed.

[0133] The adhesive of the present invention may contain, for example, known phosphoric acid or its derivatives, thereby further improving the initial adhesion of the adhesive and eliminating problems such as tunneling.

[0134] Examples of the phosphoric acid or its derivatives used herein include phosphoric acids such as hypophosphorous acid, phosphorous acid, orthophosphoric acid, and hypophosphoric acid; condensed phosphoric acids such as metaphosphoric acid, pyrophosphoric acid, tripolyphosphoric acid, polyphosphoric acid, and ultraphosphoric acid; monomethyl orthophosphate, monoethyl orthophosphate, monopropyl orthophosphate, monobutyl orthophosphate, mono-2-ethylhexyl orthophosphate, monophenyl orthophosphate, monomethyl phosphite, monoethyl phosphite, monopropyl phosphite, monobutyl phosphite; Monoesters and diesters such as mono-2-ethylhexyl phosphite, monophenyl phosphite, di-2-ethylhexyl orthophosphate, diphenyl orthophosphate, dimethyl phosphite, diethyl phosphite, dipropyl phosphite, dibutyl phosphite, di-2-ethylhexyl phosphite and diphenyl phosphite; monoesters and diesters formed from condensed phosphoric acid and alcohols; for example, those obtained by adding epoxy compounds such as ethylene oxide and propylene oxide to the above-mentioned phosphoric acids; for example, epoxy phosphates obtained by adding the above-mentioned phosphoric acids to aliphatic or aromatic diglycidyl ethers; and the like.

[0135] The above-mentioned phosphoric acid or its derivatives may be used alone or in combination of two or more. As a method of incorporating, it is sufficient to simply mix.

[0136] In addition, an adhesion promoter may be used in the adhesive of the present invention. Examples of the adhesion promoter include silane coupling agents, titanate coupling agents, aluminum coupling agents, and epoxy resins.

[0137] Examples of the silane coupling agent include aminosilanes such as γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β (aminoethyl)-γ-aminopropyltrimethoxysilane, N-β (aminoethyl)-γ-aminopropyltrimethyldimethoxysilane, and N-phenyl-γ-aminopropyltrimethoxysilane; epoxysilanes such as β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropyltriethoxysilane; vinylsilanes such as vinyltri(β-methoxyethoxy)silane, vinyltriethoxysilane, vinyltrimethoxysilane, and γ-methacryloxypropyltrimethoxysilane; hexamethyldisilazane, γ-mercaptopropyltrimethoxysilane, and the like.

[0138] Examples of the titanate coupling agent include titanium tetraisopropoxide, titanium tetra-n-butoxide, butyl titanate dimer, tetrastearyl titanate, titanium acetylacetonate, titanium lactate, tetraoctanediol titanate, titanium lactate, and tetrastearyl titanium.

[0139] Moreover, as an aluminum-based coupling agent, for example, acetoalkoxy aluminum diisopropylate etc. can be mentioned.

[0140] As the adhesion promoter, a silane coupling agent is preferably used. In addition, the content (solid content) of the adhesion promoter is preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, more preferably 0.5 parts by mass or more, and further preferably 0.7 parts by mass or more, relative to 100 parts by mass of the solid content of the polyol composition (A). In addition, the content (solid content) of the adhesion promoter is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and further preferably 5 parts by mass or less, relative to 100 parts by mass of the solid content of the polyol composition (A).

[0141] The adhesive of the present invention may further contain various additives such as ultraviolet absorbers, antioxidants, silicon-based additives, fluorine-based additives, rheology control agents, defoaming agents, antistatic agents, and antifogging agents.

[0142] (Mixing ratio)

[0143] In the adhesive of the present invention, the ratio [NCO] / [OH] of the total number of moles [OH] of hydroxyl groups contained in the polyol composition (A) to the number of moles [NCO] of isocyanate groups contained in the polyisocyanate composition (B) is preferably in the range of 1.5 to 15. This provides a two-component adhesive having excellent moldability and heat resistance. [NCO] / [OH] is more preferably 3 or more and 10 or less, and more preferably 3 or more and 8 or less.

[0144] The use of the adhesive of the present invention is not particularly limited, but since it is excellent in adhesive strength, processability, and heat resistance, it can be suitably used as a battery packaging material, for example.

[0145] <Laminate>

[0146] The laminate of the present invention is obtained by laminating a plurality of substrates by dry lamination or solvent-free lamination using the adhesive of the present invention. Examples of the substrate include paper, synthetic resin films obtained from olefin resins, acrylonitrile-butadiene-styrene copolymers (ABS resins), polyvinyl chloride resins, fluorine resins, poly(meth)acrylic resins, carbonate resins, polyamide resins, polyimide resins, polyphenylene ether resins, polyphenylene sulfide resins, and polyester resins, and metal foils such as copper foil and aluminum foil.

[0147] The film thickness of the substrate is not particularly limited, and is, for example, selected from 10 to 400 μm. In order to improve the adhesion between the substrate and the adhesive, the surface of the substrate to which the adhesive is applied may be surface treated. Examples of the surface treatment include corona treatment, plasma treatment, ozone treatment, flame treatment, and radiation treatment.

[0148] <Battery Packaging Materials>

[0149] Battery packaging materials such as Figure 1 As shown, it includes a laminated body in which at least an outer substrate layer 1, an adhesive layer 2, a metal layer 3, and a sealing layer 4 are sequentially laminated. In the battery packaging material of the present invention, the outer substrate layer 1 is the outermost layer and the sealing layer 4 is the innermost layer. That is, when the battery is assembled, the sealing layers 4 located at the periphery of the battery element are heat-fused to each other to seal the battery element, thereby sealing the battery element. The adhesive of the present invention is used for the adhesive layer 2. In addition, the battery packaging material of the present invention can be as follows Figure 2 As shown, an adhesive layer 5 is provided between the metal layer 3 and the sealing layer 4 as necessary for the purpose of improving the adhesion between them.

[0150] (Outer layer side base material layer 1)

[0151] In the battery packaging material of the present invention, the outer substrate layer 1 is a layer forming the outermost layer. As long as the raw material forming the outer substrate layer 1 has insulation properties, there is no particular restriction, and examples thereof include polyester resins, polyamide resins, epoxy resins, acrylic resins, fluororesins, polyurethane resins, silicone resins, phenolic resins, and resin films such as mixtures and copolymers thereof. Among these, polyester resins and polyamide resins are preferred, and biaxially stretched polyester resins and biaxially stretched polyamide resins are more preferred. As polyester resins, specifically, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, copolyesters, polycarbonates, etc. can be cited. In addition, as polyamide resins, specifically, nylon 6, nylon 6,6, copolymers of nylon 6 and nylon 6,6, nylon 6,10, poly(m-xylene adipamide) (MXD6), etc. can be cited.

[0152] The outer substrate layer 1 can be formed by one layer of resin film. In order to improve the pinhole resistance and insulation, it can be formed by more than two layers of resin film, for example, by a multilayer including polyethylene terephthalate film and a polyamide film. In the case where the outer substrate layer 1 is formed by a multilayer resin film, as long as the resin films are laminated with each other by means of adhesive components such as adhesives or adhesive resins, the type and amount of the adhesive components used are the same as those of the adhesive layer 2 or adhesive layer 5 described later. It should be noted that there is no particular restriction on the method for laminating more than two layers of resin films, and a known method can be adopted, for example, a dry lamination method, a sandwich lamination method (Japanese: Sandra Mineshyon method), etc., and preferably a dry lamination method can be cited. In the case of lamination by dry lamination, an adhesive is preferably used as the adhesive layer. At this time, the thickness of the adhesive layer is, for example, about 0.5 to 10 μm.

[0153] The thickness of the outer substrate layer 1 is not particularly limited as long as the battery packaging material satisfies the above-mentioned physical properties, and is, for example, about 10 to 50 μm, preferably about 15 to 35 μm. When a polyester film is used, the thickness is preferably 9 μm to 50 μm, and when a polyamide film is used, the thickness is preferably 10 μm to 50 μm. Sufficient strength as a packaging material can be ensured, and stress during bulging and drawing can be reduced, thereby improving formability.

[0154] (Metal layer 3)

[0155] In the battery packaging material, the metal layer 3 is a layer that functions as a barrier layer for preventing water vapor, oxygen, light, etc. from invading the inside of the battery in addition to improving the strength of the battery packaging material. Specifically, aluminum, stainless steel, titanium, etc. can be cited as the metal constituting the metal layer 3, preferably aluminum. The metal layer 3 can be formed by metal foil, metal vapor deposition, etc., preferably by metal foil, and more preferably by aluminum foil. In addition, in order to stabilize adhesion, prevent dissolution, prevent corrosion, etc., the metal layer 3 is preferably chemically converted on at least one surface, preferably on both surfaces. Here, chemical conversion treatment refers to a process of forming an acid-resistant coating on the surface of the metal layer.

[0156] The thickness of the metal layer 3 is not particularly limited as long as the battery packaging material satisfies the above-mentioned physical properties, and can be, for example, about 10 to 50 μm, preferably about 25 to 45 μm.

[0157] (Sealing layer 4)

[0158] In the battery packaging material of the present invention, the sealant layer 4 corresponds to the innermost layer and is a layer that seals the battery element by heat-fusion bonding the sealant layers to each other during assembly of the battery.

[0159] The resin component used for the sealant layer 4 is not particularly limited as long as it can be heat-sealed, and examples thereof include polyolefins, cyclic polyolefins, carboxylic acid-modified polyolefins, and carboxylic acid-modified cyclic polyolefins.

[0160] Specifically, the polyolefins include polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; polypropylenes such as homopolymer polypropylene, block copolymers of polypropylene (e.g., block copolymers of propylene and ethylene), and random copolymers of polypropylene (e.g., random copolymers of propylene and ethylene); terpolymers of ethylene-butene-propylene; etc. Among these polyolefins, polyethylene and polypropylene are preferred.

[0161] The cyclic polyolefin is a copolymer of an olefin and a cyclic monomer. For example, ethylene, propylene, 4-methyl-1-pentene, styrene, butadiene, isoprene, etc. can be cited as the olefin as the constituent monomer of the cyclic polyolefin. In addition, for example, cyclic olefins such as norbornene can be cited as the cyclic monomer as the constituent monomer of the cyclic polyolefin; specifically, cyclic dienes such as cyclopentadiene, dicyclopentadiene, cyclohexadiene, and norbornadiene can be cited. Among these polyolefins, cyclic olefins can be cited preferably, and norbornene can be cited more preferably.

[0162] The carboxylic acid-modified polyolefin is a polymer obtained by block-polymerizing or graft-polymerizing the polyolefin with a carboxylic acid. Examples of the carboxylic acid used for modification include maleic acid, acrylic acid, itaconic acid, crotonic acid, maleic anhydride, and itaconic anhydride.

[0163] The carboxylic acid-modified cyclic polyolefin is a polymer obtained by copolymerizing a part of the monomers constituting the cyclic polyolefin by replacing it with an α, β-unsaturated carboxylic acid or its anhydride, or by block polymerization or graft polymerization of the cyclic polyolefin with an α, β-unsaturated carboxylic acid or its anhydride. The same is true for the carboxylic acid-modified cyclic polyolefin. In addition, the carboxylic acid used in the modification is the same as the carboxylic acid used in the modification of the acid-modified cyclic olefin copolymer.

[0164] The sealing layer 4 may be formed of one resin component alone or a mixed polymer of two or more resin components. Furthermore, the sealing layer 4 may be formed of only one layer or may be formed of two or more layers of the same or different resin components.

[0165] The thickness of the sealant layer 4 is not particularly limited as long as the battery packaging material satisfies the above-mentioned physical properties, and is, for example, about 10 to 100 μm, preferably about 20 to 90 μm.

[0166] (Adhesive layer 5)

[0167] In the battery packaging material of the present invention, the adhesive layer 5 is a layer provided between the metal layer 3 and the sealant layer 4 as necessary in order to firmly adhere them.

[0168] The adhesive layer 5 is formed of an adhesive that can bond the metal layer 3 to the sealing layer 4. As the adhesive layer used in the adhesive layer 5, for example, an adhesive composed of a polyolefin resin and a multifunctional isocyanate, an adhesive composed of a polyol and a multifunctional isocyanate, or an adhesive containing a modified polyolefin resin, a heterocyclic compound, and a curing agent can be used. Alternatively, the adhesive layer 5 can be formed by melt-extruding an adhesive such as acid-modified polypropylene onto the metal layer using a T-die extruder, and the sealing layer 4 is overlapped on the adhesive layer 5 to bond the metal layer 3 to the sealing layer 4.

[0169] When both the adhesive layer 2 and the adhesive layer 5 need to be aged, they can be aged together. In addition, by setting the aging temperature to room temperature to 90° C., curing is completed in 2 days to 2 weeks, and moldability is exhibited.

[0170] The thickness of the adhesive layer 5 is not particularly limited as long as the battery packaging material satisfies the above-mentioned physical properties, and is, for example, about 0.5 to 50 μm, preferably about 2 to 30 μm.

[0171] (Coating layer 6)

[0172] In the battery packaging material of the present invention, for the purpose of improving appearance, electrolyte resistance, scratch resistance, and moldability, a coating layer 6 may be provided on the outer substrate layer 1 (on the side of the outer substrate layer 1 opposite to the metal layer 3) as required. The coating layer 6 is the outermost layer when the battery is assembled.

[0173] The coating layer 6 can be formed of, for example, polyvinylidene chloride, polyester resin, urethane resin, acrylic resin, epoxy resin, etc., and is preferably formed of a two-component curable resin. Examples of the two-component curable resin forming the coating layer 6 include two-component curable urethane resin, two-component curable polyester resin, and two-component curable epoxy resin. In addition, a matting agent (Japanese: matte chemical) can be mixed in the coating layer 6.

[0174] As the matting agent, for example, microparticles with a particle size of about 0.5 nm to 5 μm can be cited. There is no particular limitation on the material of the matting agent, and for example, metals, metal oxides, inorganic substances, organic substances, etc. can be cited. In addition, there is no particular limitation on the shape of the matting agent, and for example, spherical, fibrous, plate-like, amorphous, balloon-like, etc. can be cited. As the matting agent, specifically, talc, silicon dioxide, graphite, kaolin, montmorillonite (Japanese: モンモリロイド), montmorillonite (Japanese: モンモリロナイト), synthetic mica, hydrotalcite, silica gel, zeolite, aluminum hydroxide, magnesium hydroxide, zinc oxide, magnesium oxide, aluminum oxide, neodymium oxide, antimony oxide, titanium oxide, cerium oxide, calcium sulfate, barium sulfate, calcium carbonate, calcium silicate, lithium carbonate, calcium benzoate, calcium oxalate, magnesium stearate, carbon black, carbon nanotubes, high melting point nylon, cross-linked acrylic acid, cross-linked styrene, cross-linked polyethylene, benzoguanamine, gold, aluminum, copper, nickel, etc. can be cited. These matting agents can be used alone or in combination of two or more. Among these matting agents, silicon dioxide, barium sulfate, and titanium oxide are preferred from the viewpoints of dispersion stability, cost, etc. In addition, the matting agent can be subjected to various surface treatments such as insulation treatment and high dispersibility treatment on the surface.

[0175] The method for forming the coating layer 6 is not particularly limited, and one example is a method of applying a two-component curable resin forming the coating layer 6 to one surface of the outer substrate layer 1. When a matting agent is added, the matting agent may be added to the two-component curable resin and mixed before application.

[0176] (Method for producing battery packaging material)

[0177] The method for producing the battery packaging material of the present invention is not particularly limited as long as a laminated body in which layers having predetermined compositions are laminated can be obtained, and the following methods can be exemplified.

[0178] First, a laminate (hereinafter sometimes referred to as "laminate A") is formed in which an outer substrate layer 1, an adhesive layer 2, and a metal layer 3 are laminated in sequence. The laminate A can be formed specifically by the following dry lamination method: the adhesive of the present invention is applied to the outer substrate layer 1 or the metal layer 3 whose surface has been chemically converted as required by a coating method such as an extrusion method, a gravure coating method, a roll coating method, and after drying, the metal layer 3 or the outer substrate layer 1 is laminated and the adhesive layer 2 is cured.

[0179] Next, the sealant layer 4 is laminated on the metal layer 3 of the laminate A. When the sealant layer 4 is laminated directly on the metal layer 3, the resin component constituting the sealant layer 4 can be applied to the metal layer 3 of the laminate A by a method such as a gravure coating method or a roll coating method. In addition, when an adhesive layer 5 is provided between the metal layer 3 and the sealing layer 4, for example, the following methods can be cited: a method of laminating the adhesive layer 5 and the sealing layer 4 on the metal layer 3 of the stack A by co-extrusion (co-extrusion lamination method); a method of separately forming a stack having the adhesive layer 5 and the sealing layer 4 laminated thereon, and laminating it on the metal layer 3 of the stack A by a heat lamination method; a method of laminating an adhesive for forming the adhesive layer 5 on the metal layer 3 of the stack A by an extrusion method, a method of drying at a high temperature for solution coating, and then baking, and laminating the sealing layer 4 pre-filmed in a sheet form on the adhesive layer 5 by a heat lamination method; a method of allowing the molten adhesive layer 5 to flow between the metal layer 3 of the stack A and the sealing layer 4 pre-filmed in a sheet form, and bonding the stack A and the sealing layer 4 with the aid of the adhesive layer 5 (sandwich lamination method), etc.

[0180] When the coating layer 6 is provided, the coating layer 6 is laminated on the surface of the outer layer side substrate layer 1 on the opposite side to the metal layer 3. The coating layer 6 is formed, for example, by coating the above-mentioned resin forming the coating layer 6 on the surface of the outer layer side substrate layer 1. It should be noted that the order of the process of laminating the metal layer 3 on the surface of the outer layer side substrate layer 1 and the process of laminating the coating layer 6 on the surface of the outer layer side substrate layer 1 is not particularly limited. For example, after the coating layer 6 is formed on the surface of the outer layer side substrate layer 1, the metal layer 3 can be formed on the surface of the outer layer side substrate layer 1 on the opposite side to the coating layer 6.

[0181] As described above, a laminated body is formed, which includes a coating layer 6 provided as required / an outer layer substrate layer 1 / an adhesive layer 2 / a metal layer 3 having a surface subjected to a chemical conversion treatment as required / an adhesive layer 5 provided as required / a sealing layer 4. In order to strengthen the adhesion of the adhesive layer 2 and the adhesive layer 5 provided as required, the laminated body may be further subjected to a heat treatment such as a hot roll contact type, a hot air type, a near or far infrared type, etc. The conditions for such a heat treatment may be, for example, 150 to 250° C. for 1 to 5 minutes.

[0182] In the battery packaging material of the present invention, in order to improve or stabilize the film forming properties, lamination processing, and suitability for secondary processing (bagging, embossing molding) of the final product, each layer constituting the laminate can be subjected to surface activation treatment such as corona treatment, sandblasting, oxidation treatment, and ozone treatment as needed.

[0183] <Battery Container>

[0184] The battery container of the present invention can be obtained by using the above-mentioned battery packaging material and molding it so that the outer layer side base material layer 1 forms a convex surface and the sealing layer 4 forms a concave surface.

[0185] In addition, as a method of forming the recessed portion, there are the following methods.

[0186] Heating and pressure molding: A method in which a battery packaging material is sandwiched between a lower mold having a hole for supplying high-temperature, high-pressure air and an upper mold having a bag-shaped recessed portion, and air is supplied while heating and softening to form the recessed portion.

[0187] Preheater flat plate pressure molding method: After the battery packaging material is heated and softened, it is sandwiched between a lower mold having a hole for supplying high-pressure air and an upper mold having a bag-shaped recessed portion, and air is supplied to form the recessed portion.

[0188] Roller vacuum forming method: A method in which a battery packaging material is partially heated and softened using a heated roll, and then the roll having a bag-shaped recessed portion is evacuated to form the recessed portion.

[0189] Pin forming method: A method in which the base sheet is heated and softened and then crimped with a bag-shaped concave and convex mold.

[0190] Preheater plunger assisted pressure molding method: After the battery packaging material is heated and softened, it is clamped between a lower mold having a hole for supplying high-pressure air and an upper mold having a bag-shaped recessed portion, and air is supplied to form the recessed portion. During molding, a convex plunger is raised and lowered to assist molding.

[0191] Among them, the preheater plunger-assisted pressure forming method, which is a heating vacuum forming method, is preferable in that the wall thickness of the base material after forming can be uniform.

[0192] (Application of battery packaging materials)

[0193] The battery packaging material of the present invention is used as a battery container for sealing and housing battery components such as a positive electrode, a negative electrode, and an electrolyte.

[0194] Specifically, a battery element having at least a positive electrode, a negative electrode, and an electrolyte is covered with the battery packaging material of the present invention, so that a flange portion (an area where sealing layers are in contact with each other) can be formed on the periphery of the battery element while metal terminals connected to the positive electrode and the negative electrode protrude to the outside, and the sealing layers of the flange portion are heat-sealed to each other, thereby providing a battery using the battery packaging material. It should be noted that when the battery packaging material of the present invention is used to store the battery element, the sealing portion of the battery packaging material of the present invention is used in a manner that the sealing portion becomes the inner side (the surface in contact with the battery element).

[0195] The battery packaging material of the present invention can be used in both primary and secondary batteries, and preferably can be used in secondary batteries. There is no particular restriction on the type of secondary battery to which the battery packaging material of the present invention is applied, and for example, lithium ion batteries, lithium ion polymer batteries, solid batteries, lead storage batteries, nickel-hydrogen storage batteries, nickel-cadmium storage batteries, nickel-iron storage batteries, nickel-zinc storage batteries, silver oxide-zinc storage batteries, metal-air batteries, multivalent cation batteries, capacitors (condenser), capacitors (capacitor), etc. can be cited. Among these secondary batteries, lithium ion batteries, lithium ion polymer batteries, and solid batteries can be cited as appropriate application objects of the battery packaging material of the present invention.

[0196] Example

[0197] Hereinafter, specific synthesis examples and embodiments are given to explain the present invention in more detail, but the present invention is not limited to these embodiments. It should be noted that, in the following examples, "parts" and "%" represent "parts by mass" and "mass %" respectively unless otherwise specified.

[0198] <Polyol composition (A)>

[0199] (Synthesis Example 1) Synthesis of Polyester Polyol (A1-1)

[0200] In a 2-liter glass four-necked flask equipped with a stirring blade, a temperature sensor, a nitrogen inlet pipe, and a distillation column, 790.8 parts of isophthalic acid, 339.4 parts of terephthalic acid, 20.0 parts of trimellitic anhydride, 738.0 parts of 1,6-hexanediol, and 107.4 parts of neopentyl glycol were used to synthesize a polyester polyol according to a conventional method. The obtained polyester polyol was diluted with ethyl acetate to a resin solid content of 58%, and a number average molecular weight (Mn) of 7,900, a weight average molecular weight (Mw) of 25,700, a resin hydroxyl value (solid content conversion) of 22.2 mgKOH / g, a resin acid value (solid content conversion) of 0.82 mgKOH / g, and a glass transition temperature (Tg) of 7.3°C were obtained. Polyester polyol (A1-1)

[0201] (Synthesis Example 2) Synthesis of Polyester Polyol (A1-2)

[0202] In a 2-liter glass four-necked flask equipped with a stirring blade, a temperature sensor, a nitrogen inlet pipe, and a distillation column, 697.2 parts of terephthalic acid, 72.9 parts of ethylene glycol, and 229.9 parts of 1,2-propylene glycol were used to obtain a polyester polyol according to a conventional method. The obtained polyester polyol was diluted with methyl ethyl ketone to a resin solid content of 30%, and a number average molecular weight (Mn) of 8,400, a weight average molecular weight (Mw) of 61,300, a resin hydroxyl value (solid content conversion) of 5.0 mgKOH / g, a resin acid value (solid content conversion) of 4.0 mgKOH / g, and a glass transition temperature of 84°C were obtained. Polyester polyol (A1-2)

[0203] (Synthesis Example 3) Synthesis of Polyester Polyol (A1-3)

[0204] In a 2-liter glass four-necked flask equipped with a stirring blade, a temperature sensor, a nitrogen inlet pipe, and a distillation column, 300.3 parts of isophthalic acid, 300.3 parts of terephthalic acid, 37.7 parts of neopentyl glycol, 101.0 parts of ethylene glycol, and 260.7 parts of 1,9-nonanediol were used to synthesize a polyester polyol according to a conventional method. The obtained polyester polyol was diluted with methyl ethyl ketone to a resin solid content of 60%, and a polyester polyol (A1-3) having a number average molecular weight (Mn) of 3,000, a weight average molecular weight (Mw) of 16,000, a resin hydroxyl value (solid content conversion) of 19.2 mgKOH / g, a resin acid value (solid content conversion) of 0.55 mgKOH / g, and a glass transition temperature (Tg) of 10.7°C was obtained.

[0205] The physical properties of the polyester polyol were measured as follows.

[0206] (Molecular weight determination method)

[0207] Measuring device: HLC-8320GPC manufactured by Tosoh Corporation

[0208] Column; TSKgel 4000HXL, TSKgel 3000HXL, TSKgel 2000HXL, TSKgel1000HXL manufactured by Tosoh Corporation

[0209] Detector: RI (differential refractometer)

[0210] Data processing: Multi-station GPC-8020model II manufactured by Tosoh Corporation

[0211] Determination conditions: column temperature 40°C

[0212] Solvent Tetrahydrofuran

[0213] Flow rate 0.35ml / min

[0214] Standard; monodisperse polystyrene

[0215] Sample: A substance obtained by filtering a tetrahydrofuran solution containing 0.2% by mass of the resin solid content using a microfilter (100 μl)

[0216] (Acid value determination method)

[0217] Weigh 5.0 g of the sample accurately, add 30 mL of a neutral solvent to dissolve it, and titrate with a 0.1 mol / L potassium hydroxide solution (methanolic). Use phenolphthalein as the indicator. The measurement result is converted into the amount of potassium hydroxide required to neutralize 1 g of the sample, and the unit is mgKOH / g.

[0218] (Hydroxy value determination method)

[0219] Accurately weigh 4.0g of the sample (converted to solid content), add 25mL of an acetylating agent containing acetic anhydride / pyridine (volume ratio 1 / 19), seal, and heat at 100°C for 1 hour. After acetylation, add 10mL of ion exchange water and 100mL of tetrahydrofuran, and titrate with 0.5mol / L potassium hydroxide solution (alcoholic). Phenolphthalein is used as an indicator. The measurement result is converted into the amount of potassium hydroxide required to neutralize the acetic acid generated when 1g of the sample is acetylated, and the unit is set to mgKOH / g.

[0220] (Glass transition temperature measurement method)

[0221] Using DSC, 5 mg of the sample was heated from room temperature to 200°C at 10°C / min under a nitrogen flow of 30 mL / min, then cooled to -80°C at 10°C / min, and heated again to 150°C at 10°C / min to measure the DSC curve. The intersection of a straight line extending the baseline on the low temperature side to the high temperature side in the measurement result observed in the second heating step and a tangent drawn at the point where the slope of the curve of the step-shaped portion of the glass transition becomes the maximum was taken as the glass transition point, and the temperature at this time was taken as the glass transition temperature.

[0222] <Polyisocyanate composition (B)>

[0223] (Synthesis Example 4) Synthesis of Polyester Polyol (B1'-1)

[0224] In a 2-liter glass four-necked flask equipped with a stirring blade, a temperature sensor, a nitrogen inlet pipe and a distillation tower, 47.3 parts of 1,6-hexanediol and 52.7 parts of phthalic anhydride were added. The temperature was gradually raised to 220°C under a nitrogen flow at normal pressure for dehydration reaction, and the reaction was continued at 220°C. After confirming that the top temperature of the distillation tower was below 80°C, the distillation tower was removed and switched to a glass condenser, and the pipeline was connected from the nitrogen inlet pipe to a vacuum pump. The condensation reaction was carried out under a reduced pressure of 50 Torr until the specified acid value was reached, thereby obtaining a polyester polyol (B1'-1). The number average molecular weight (Mn) of the polyester polyol (B1'-1) was 1,800, the weight average molecular weight (Mw) was 4,600, the hydroxyl value was 54 mgKOH / g, and the acid value was 1.0 mgKOH / g.

[0225] (Synthesis Example 5) Synthesis of Polyester Polyol (BH1')

[0226] In a 2-liter glass four-necked flask equipped with a stirring blade, a temperature sensor, a nitrogen inlet pipe and a distillation tower, 12.2 parts of ethylene glycol, 27.4 parts of neopentyl glycol, 51.5 parts of adipic acid and 8.9 parts of isophthalic acid were added. The temperature was gradually raised to 220°C under a nitrogen flow at normal pressure for dehydration reaction, and the reaction was continued at 220°C. After confirming that the top temperature of the distillation tower was below 80°C, the distillation tower was removed and switched to a glass condenser, and the pipeline was connected from the nitrogen inlet pipe to a vacuum pump. The condensation reaction was carried out under a reduced pressure of 50 Torr until the specified acid value was reached, thereby obtaining a polyester polyol (BH1'). The number average molecular weight (Mn) of the polyester polyol (BH1') was 1,500, the weight average molecular weight (Mw) was 5,000, the hydroxyl value was 70 mgKOH / g, and the acid value was 1.0 mgKOH / g.

[0227] (Synthesis Example 6) Synthesis of urethane prepolymer (B1-1)

[0228] Into a 2-liter four-necked glass flask equipped with a stirrer, a thermometer and a nitrogen inlet tube, 50.6 parts of a mixture of 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate in a ratio of 54:45:1 (mass ratio) was added as an isocyanate composition (B1"), and heated to 60°C while stirring under a nitrogen stream. 49.4 parts of the polyester polyol (B1'-1) was added dropwise in multiple portions, and the mixture was heated and maintained at an internal temperature of 80°C for 4 hours to carry out a urethanization reaction, thereby obtaining a urethane prepolymer (B1-1) having an NCO group content of 15.0% and having isocyanate groups at both ends.

[0229] (Synthesis Examples 7 to 11) Synthesis of Urethane Prepolymers (B1-2 to B1-5, BH1)

[0230] Urethane prepolymers (B1-2) to (B1-5) and (BH1) were synthesized in the same manner as in Synthesis Example 6, except that the polyester polyol (B1') and its blending amount, the blending amount of the isocyanate composition (B1"), and the polyol (B1'") and its blending amount were changed as shown in Table 1.

[0231] [Table 1]

[0232]

[0233] <Preparation of Adhesive>

[0234] (Example 1)

[0235] Urethane prepolymer (B1-1) was added to polyester polyol (A1-1) and polyester polyol (A1-2), and ethyl acetate was further added so that the nonvolatile content was 30%, and the mixture was stirred thoroughly to prepare an adhesive of Example 1. The amount (solid content) of each component in the adhesive of Example 1 is shown in Table 2.

[0236] (Example 2) to (Example 7)

[0237] Adhesives of Examples 2 to 7 were produced in the same manner as in Example 1 except that the materials and compounding used for preparing the adhesive were adjusted to the values ​​described in Tables 2 and 3.

[0238] (Comparative Example 1), (Comparative Example 2)

[0239] Adhesives of Comparative Examples 1 and 2 were produced in the same manner as in Example 1, except that the materials and compounding used for preparing the adhesive were adjusted to the values ​​described in Table 3.

[0240] Among the compounds in Tables 2 and 3, the details of the compounds not described above are as follows.

[0241] TDI-TMP adduct: adduct of toluene diisocyanate and trimethylolpropane

[0242] MDI50: a mixture of 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate in a ratio of 54:45:1 (mass ratio)

[0243] <Manufacture of battery packaging materials Figure 2 Composition>

[0244] (Example 1)

[0245] The matte surface of an aluminum foil having a thickness of 40 μm serving as the metal layer 3 is coated with the adhesive of Example 1 in an amount of 3 g / m2 using a dry laminator as the adhesive layer 2. After the solvent is evaporated, a stretched polyamide film having a thickness of 25 μm is laminated as the outer substrate layer 1.

[0246] Next, the glossy surface of the aluminum foil of the metal layer 3 of the obtained laminated film is coated with an adhesive for the bonding layer 5 in an amount of 3 g / m2 using a dry laminator, and after the solvent is evaporated, a 40 μm thick unstretched polypropylene film is laminated as a sealing layer 4, and then cured (ripened) at 60°C for 5 days to cure the adhesive and obtain a laminate.

[0247] (Example 2) to (Example 7)

[0248] In the same manner as in Example 1, the adhesives of Examples 2 to 7 were used as the adhesive layer 2 to obtain battery packaging materials of Examples 2 to 7.

[0249] (Comparative Example 1), (Comparative Example 2)

[0250] The same operation as in Example 1 was carried out except that the adhesives of Comparative Examples 1 and 2 were used as the adhesive layer 2 to obtain the battery packaging materials of Comparative Examples 1 and 2.

[0251] Evaluation of the battery packaging material was performed as follows.

[0252] <Adhesion Strength>

[0253] The adhesive strength at the interface between the outer substrate layer 1 and the metal layer 3 of the battery packaging material of the example or comparative example was evaluated using "Autograph AGS-J" of Shimadzu Corporation at a peeling speed of 50 mm / min, a peeling width of 15 mm, and a peeling shape of 180°. A higher value indicates a more suitable adhesive.

[0254] <Heat Intensity>

[0255] The adhesive strength of the interface between the outer substrate layer 1 and the metal layer 3 of the battery packaging material of the example or comparative example was evaluated under the conditions of 120°C atmosphere, peeling speed 50 mm / min, peeling width 15 mm, and free peeling using "Temperature Chamber TLF-R2-S for Tensile Tester" manufactured by ORIENTEC CORPORATION and "RTG-1210" manufactured by A&D Company, Limited. The higher the value, the more suitable it is as an adhesive.

[0256] <Moldability>

[0257] The battery packaging material of the embodiment or comparative example was cut into a size of 60×60 mm using the "Lton Table Servo Press (SBN-1000)" of Yamaoka Manufacturing Co., Ltd. to make a blank (molded material, raw material). For the blank, the matte surface of the aluminum foil was made convex, and the molding height was changed from 3.0 mm to 5.0 mm using a straight die with free molding height, and the molding was performed. The moldability was evaluated using the maximum molding height without breaking the aluminum foil or floating between the layers.

[0258] It should be noted that the punch shape of the die used was a square with a side of 30 mm, a corner of R2 mm, and a punch shoulder of R1 mm. The die hole shape of the die used was a square with a side of 34 mm, a die hole corner of R2 mm, and a die hole shoulder R: 1 mm. The gap between the punch and the die hole was 0.3 mm on one side. The gap caused an inclination corresponding to the molding height. The following three stages of evaluation were performed according to the molding height.

[0259] ○: 5.0 mm or more (excellent in practical use)

[0260] △: 4.0mm (practical range)

[0261] ×: Aluminum foil breaks at 4.0 mm and lifting occurs between layers

[0262] [Table 2]

[0263]

[0264] [Table 3]

[0265]

[0266] From the present results, it is clear that a battery packaging material having excellent moldability and heat resistance can be obtained by using the adhesive of the present invention.

[0267] Description of Reference Numerals

[0268] 1: Outer side base material layer

[0269] 2: Adhesive layer

[0270] 3: Metal layer

[0271] 4: Sealing layer

[0272] 5: Adhesive layer

Claims

1. A two-component solvent-based adhesive comprising a polyol composition A and a polyisocyanate composition B, The polyisocyanate composition B comprises a carbamate prepolymer B1, wherein the carbamate prepolymer B1 is a reaction product of a polyester polyol B1' and a polyisocyanate composition B1" comprising an aromatic polyisocyanate, wherein the polyester polyol B1' is a reaction product of a polyol a and a polycarboxylic acid b, wherein 50% by mass or more of the polyol a is an aliphatic diol a1 having 4 to 10 carbon atoms in a methylene chain between two hydroxyl groups, and 60% by mass or more of the polycarboxylic acid b is an aromatic polycarboxylic acid b1, The polyol composition A comprises a polyester polyol A1 having a polybasic acid or its derivative and a polyol as essential raw materials, wherein the proportion of the polybasic acid or its derivative having an aromatic ring in the polybasic acid or its derivative is 30 mol % or more, The number average molecular weight of the polyester polyol A1 is 2000-100000, The ratio [NCO] / [OH] of the total number of moles of hydroxyl groups [OH] contained in the polyol composition A to the number of moles of isocyanate groups [NCO] contained in the polyisocyanate composition B is in the range of 1.5 to 15.

2. The two-component solvent-based adhesive according to claim 1, in, The polyisocyanate composition B contains a trifunctional or higher-functional aromatic polyisocyanate compound B2.

3. The two-component solvent-based adhesive according to claim 1 or 2, in, The polyol a includes a trifunctional or higher polyol.

4. The two-component solvent-based adhesive according to claim 1 or 2, in, 30 mass % or more of the aromatic polycarboxylic acid b1 is phthalic acid or a derivative thereof. 5 . A laminated body obtained by bonding a plurality of substrates together using the two-component solvent-based adhesive according to claim 1 .

6. A battery packaging material, It is characterized in that At least an outer substrate layer 1, an adhesive layer 2, a metal layer 3 and a sealant layer 4 are laminated in this order, and the adhesive layer 2 is a cured product of the two-component solvent-based adhesive according to any one of claims 1 to 4.

7. A battery container, which is obtained by molding the battery packaging material according to claim 6.

8. A battery comprising the battery container according to claim 7.

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