JP7024911B2 - Adhesives, battery packaging adhesives, laminates, battery packaging materials, battery containers and batteries - Google Patents

Description

The present invention relates to an adhesive, particularly a reactive adhesive suitable for a battery container for forming a lithium ion battery or a battery packaging material for forming a battery pack, a laminate obtained by using the reactive adhesive, a battery packaging material, and the like. Regarding battery containers and batteries.

With the rapid spread of electronic devices such as mobile phones and portable personal computers, the demand for various types of batteries such as lithium-ion batteries is increasing. In these batteries, electronic elements such as electrodes and electrolytes are sealed with a packaging material, and metal cans (metal cans) are often used as the packaging material.

On the other hand, in recent years, with the improvement of the performance of in-vehicle devices such as electric vehicles and hybrid electric vehicles, home storage, personal computers, cameras, mobile phones, etc., batteries are required to have various shapes, and are required to be thinner and lighter. ing. However, it is difficult to cope with the diversification of shapes with the packaging material for batteries of metal cans, and there is a limit to the weight reduction. Therefore, as a battery packaging material that can be easily processed into various shapes and can be made thinner and lighter, it is in the form of a film in which an outer layer side base material layer, an adhesive layer, a metal layer, and a sealant layer are sequentially laminated. Laminates have been proposed.
When the packaging material for a battery made of these film-like laminates is molded so that the outer layer side base material layer side forms a convex surface and the sealant layer side forms a concave surface in order to form a battery container or a battery pack. There is.
Further, in the battery packaging material, the outer layer side base material layer is the outer layer and the sealant layer is the inner layer, and when the battery is assembled, the sealant layers located on the peripheral edge of the battery element are heat-sealed to seal the battery element. , The battery element is sealed.

Among these, secondary batteries for in-vehicle and home storage applications are installed outdoors and are required to have a long service life, and even in an open-air environment, the adhesiveness between the layers of each plastic film and metal leaf of the packaging material. Is required to be maintained for a long period of time and to have no abnormality in appearance.

In order to enhance the characteristics of these film-shaped battery packaging materials, various studies have been conducted focusing on an adhesive layer for adhering a plastic film and a metal layer.
For example, Patent Document 1 describes the first adhesive layer in a laminated packaging material including an inner layer made of a resin film, a first adhesive layer, a metal layer, a second adhesive layer, and an outer layer made of a resin film. And by forming at least one of the second adhesive layers with an adhesive composition containing a resin having an active hydrogen group in the side chain, polyfunctional isocyanates, and a polyfunctional amine compound, it is reliable for deeper molding. It is disclosed that a high-quality packaging material can be obtained.

Further, Patent Document 2 describes that the outer layer side adhesive layer of the battery packaging material having the outer layer side resin film layer, the outer layer side adhesive layer, the metal foil layer, the inner layer side adhesive layer, and the heat seal layer has a number average molecular weight. An acrylic polyol (A) having a hydroxyl value of 1 to 100 mgKOH / g and an isocyanate curing agent of 10,000 to 100,000 is used, and is contained in the curing agent for the hydroxyl group derived from the acrylic polyol (A). By using an adhesive having an equivalent ratio [NCO] / [OH] of isocyanate groups derived from aromatic polyisocyanate (B) of 10 to 30, it has excellent moldability and even after a long-term durability test. It is disclosed that a packaging material for a battery can be obtained without a decrease in adhesive strength between layers and without appearance defects such as floating between layers.

Further, Patent Document 3 contains a polyester polyol (A1): 85 to 99% by weight, and a trifunctional or higher functional alcohol component (A2): 1 to 15% by weight as an outer layer side adhesive layer having the same structure as Patent Document 2. The polyester polyol (A1) is a polyester polyol having a number average molecular weight of 5,000 to 50,000 composed of a polybasic acid component and a polyhydric alcohol component, and is aromatic in 100 mol% of the polybasic acid component. The polyol component (A) containing 45 to 95 mol% of the basic acid component and the isocyanate curing agent are used, and the equivalent ratio of the isocyanate groups contained in the curing agent to the total of the hydroxyl groups and the carboxyl groups derived from the polyol (A) [ By using an adhesive having NCO] / ([OH] + [COOH]) of 0.5 to 10, it has excellent moldability, and is hot and humid at 105 ° C, 100% RH, and 168 hours. -It is disclosed that a packaging material for a battery can be obtained without a decrease in adhesive strength between layers even after a long-term durability test and without appearance defects such as floating between layers.

Japanese Unexamined Patent Publication No. 2008-287971 Japanese Unexamined Patent Publication No. 2014-185317 Japanese Unexamined Patent Publication No. 2015-82354

The present invention has excellent moldability, and the adhesive strength between the layers is high even after heat fusion between the sealant layers performed for sealing the battery element and also after a long-term durability test under high temperature and high humidity. It is an object of the present invention to provide a battery packaging material which does not deteriorate and does not have an appearance defect such as floating between layers. Another object of the present invention is to provide a reactive adhesive having excellent moldability, heat resistance, and moisture heat resistance, which is suitable for producing a packaging material for a battery.

The present inventors include a polyol composition (A) and a polyisocyanate composition (B), and the polyisocyanate composition (B) contains an isocyanate compound (B1) and an isocyanate compound (B2), and the isocyanate compound (B). B1) contains an aromatic polyisocyanate, and the isocyanate compound (B2) is 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, and at least one of these diphenylmethane diisocyanates in the presence of a catalyst. The above-mentioned problem was solved by using a two-component adhesive characterized by containing at least one selected from the group consisting of carbodiimide-modified diphenylmethane diisocyanate condensed with.

That is, the present invention contains a polyol composition (A) and a polyisocyanate composition (B), and the polyisocyanate composition (B) contains an isocyanate compound (B1) and an isocyanate compound (B2), and the isocyanate compound (B1) is contained. ) Contains an aromatic polyisocyanate, the isocyanate compound (B2) is 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, and at least one of these diphenylmethane diisocyanates in the presence of a catalyst. The present invention relates to a two-component adhesive comprising at least one selected from the group consisting of condensed carbodiimide-modified diphenylmethane diisocyanate.

The present invention also relates to a laminate in which a plurality of base materials are bonded together using the above-mentioned two-component adhesive.

Further, the present invention is a packaging material for a battery in which at least an outer layer side base material layer 1, an adhesive layer 2, a metal layer 3, and a sealant layer 4 are sequentially laminated, and the adhesive layer 2 is a two-component type described above. The present invention relates to a packaging material for a battery, which is a cured product of an adhesive.

The present invention also relates to a battery container obtained by molding the above-mentioned battery packaging material.

The present invention also relates to a battery using the battery container described above.

By using the adhesive of the present invention, it has excellent moldability, after heat fusion between the sealant layers performed to seal the battery element, and after a long-term durability test under high temperature and high humidity. It is also possible to obtain a battery packaging material that does not have a decrease in adhesive strength between layers and does not have an appearance defect such as floating between layers. A battery container made of the battery packaging material of the present invention can provide a highly reliable battery.

This is an example of a specific embodiment of the laminated body in which the outer layer side base material layer 1, the adhesive layer 2, the metal layer 3, and the sealant layer 4 are sequentially laminated. This is an example of a specific embodiment of the laminated body in which the outer layer side base material layer 1, the adhesive layer 2, the metal layer 3, the adhesive layer 5, and the sealant layer 4 are sequentially laminated.

<Adhesive>
The adhesive of the present invention contains a polyol composition (A) and a polyisocyanate composition (B) as essential components, and the polyisocyanate composition (B) contains an isocyanate compound (B1) containing an aromatic polyisocyanate and diphenylmethane diisocyanate. It is a two-component adhesive containing an isocyanate compound (B2) containing at least one selected from the group consisting of carbodiimide-modified forms of diphenylmethane diisocyanate.

(Polyform composition (A))
(Polyester polyol (A1))
The polyol composition (A) used in the adhesive of the present invention contains a polyester polyol (A1) containing a polybasic acid or a derivative thereof and a polyhydric alcohol as essential raw materials.

Examples of the polybasic acid or its derivative used as a raw material for the polyester polyol (A1) include malonic acid, ethylmalonic acid, dimethylmalonic acid, succinic acid, 2,2-dimethylsuccinic acid, anhydrous succinic acid, and alkenyl anhydride succinic acid. An aliphatic polybasic acid such as glutaric acid, adipic acid, pimelli acid, suberic acid, azelaic acid, sevacinic acid, fumaric acid, malonic acid, malonic acid anhydride, and itaconic acid;

An aliphatic polybasic acid such as dimethyl malonate, diethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, diethyl pimelic acid, diethyl sebacate, dimethyl fumarate, diethyl fumarate, dimethyl maleate, diethyl maleate, etc. Alkyl esterified product;

1,1-Cyclopentane dicarboxylic acid, 1,2-Cyclopentane dicarboxylic acid, 1,3-Cyclopentane dicarboxylic acid, 1,2-Cyclohexanedicarboxylic acid, 1,3-Cyclohexanedicarboxylic acid, 1,4-Cyclohexanedicarboxylic acid , Tetrahydro phthalic acid anhydride, 4-methylhexahydrophthalic acid anhydride, hexahydrophthalic acid anhydride, cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydrous, hymic acid anhydride, het acid anhydride and the like. Group polybasic acid;

Orthophthalic acid, terephthalic acid, isophthalic acid, anhydrous phthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid anhydride, naphthalic acid, Trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, biphenyldicarboxylic acid, 1,2-bis (phenoxy) ethane-p, p'-dicarboxylic acid, benzophenonetetracarboxylic acid, benzophenonetetracarboxylic acid di Aromatic polybasic acids such as anhydrides, 5-sodium sulfoisophthalic acid, tetrachlorohydride phthalic acid, tetrabromohydride phthalic acid;

Methyl esterified products of aromatic polybasic acids such as dimethyl terephthalic acid and dimethyl 2,6-naphthalenedicarboxylic acid; and the like; one type or a combination of two or more types can be used.

The polyhydric alcohol may be a diol or a trifunctional or higher functional polyol, and the diol may be, for example, ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,2,2-trimethyl-1,3-. Propylene diol, 2,2-dimethyl-3-isopropyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 3-methyl-1,3-butanediol, 1,5-pentane Diore, 3-methyl 1,5-pentanediol, neopentanediol, 1,6-hexanediol, 1,4-bis (hydroxymethyl) cyclohesane, 2,2,4-trimethyl-1,3-pentanediol, etc. Aliper diol;

Ether glycols such as polyoxyethylene glycol and polyoxypropylene glycol;

Modifications obtained by ring-opening polymerization of the aliphatic diol 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. Polyether diol;

A lactone-based polyester polyol obtained by a polycondensation reaction between the aliphatic diol and various lactones such as lactanoid and ε-caprolactone;

Bisphenols such as bisphenol A and bisphenol F;

Examples thereof include an alkylene oxide adduct of bisphenol obtained by adding ethylene oxide, proprene oxide and the like to bisphenol such as bisphenol A and bisphenol F.

The trifunctional or higher functional polyol is an aliphatic polyol such as trimethylolethane, trimethylolpropane, glycerin, hexanetriol, or pentaerythritol;

Modifications obtained by ring-opening polymerization of the aliphatic polyol 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. Polyether polyol;

Examples thereof include a lactone-based polyester polyol obtained by a polycondensation reaction between the aliphatic polyol and various lactones such as ε-caprolactone.

In the present invention, it is preferable to contain a branched alkylene diol as the polyhydric alcohol because the appearance of the laminate is improved.

The branched alkylene diol is specifically an alkylene diol having a tertiary carbon atom or a quaternary carbon atom in its molecular structure, and is, for example, 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, Examples thereof include 2,2,4-trimethyl-1,3-pentanediol, and these can be used alone or in combination of two or more. Among these, neopentyl glycol is particularly preferable from the viewpoint of obtaining a polyester polyol (A1) having excellent moisture and heat resistance.

In the present invention, the polyester polyol (A1) may be a polyester polyurethane polyol containing a polybasic acid or a derivative thereof, a polyhydric alcohol, and a polyisocyanate as essential raw materials. Examples of the polyisocyanate used in that case include a diisocyanate compound and a trifunctional or higher functional polyisocyanate compound. Each of these polyisocyanates may be used alone or in combination of two or more.

Examples of the diisocyanate compound include butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, xylylene diisocyanate, and m-tetramethylxylylene diisocyanate. An aliphatic diisocyanate such as isocyanate and lysine diisocyanate;

Cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis (isocyanatemethyl) cyclohexane, methylcyclohexane diisocyanate, isopropyridene dicyclohexyl-4,4'-diisocyanate, norbornane diisocyanate, etc. Alicyclic diisocyanate;

1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyldiisocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3-phenylenediocyanate , 1,4-Phenylene diisocyanate, tolylene diisocyanate and other aromatic diisocyanates.

Examples of the trifunctional or higher functional polyisocyanate compound include an adduct-type polyisocyanate compound having a urethane bond site in the molecule and a nurate-type polyisocyanate compound having an isocyanurate ring structure in the molecule.

The adduct-type polyisocyanate compound having a urethane bond site in the molecule is obtained, for example, by reacting a diisocyanate compound with a polyhydric alcohol. Examples of the diisocyanate compound used in the reaction include various diisocyanate compounds exemplified as the diisocyanate compound, and these may be used alone or in combination of two or more. Further, examples of the polyol compound used in the reaction include various polyol compounds exemplified as the polyhydric alcohol, polyester polyol obtained by reacting the polyhydric alcohol with a polybasic acid, and the like, and these are used alone. You may use it, or you may use two or more types together.

The nurate-type polyisocyanate compound having an isocyanurate ring structure in the molecule is obtained, for example, by reacting a diisocyanate compound with a monoalcohol and / or a diol. Examples of the diisocyanate compound used in the reaction include various diisocyanate compounds exemplified as the diisocyanate compound, and these may be used alone or in combination of two or more. Examples of the monoalcohol used in the reaction include hexanol, 2-ethylhexanol, octanol, n-decanol, n-undecanol, n-dodecanol, n-tridecanol, n-tetradecanol, n-pentadecanol and n-. Heptadecanol, n-octadecanol, n-nonadecanol, eikosanol, 5-ethyl-2-nonanol, trimethylnonyl alcohol, 2-hexyldecanol, 3,9-diethyl-6-tridecanol, 2-isoheptylisoundecanol , 2-octyldodecanol, 2-decyltetradecanol and the like, and examples of the diol include the aliphatic diol exemplified by the polyhydric alcohol. These monoalcohols and diols may be used alone or in combination of two or more.

The polyester polyol (A1) used in the present invention is a reaction product of a polybasic acid or a derivative thereof and a polyvalent alcohol, and the ratio of the polybasic acid having an aromatic ring or a derivative thereof in the polybasic acid or a derivative thereof. Is preferably 30 mol% or more. This makes it possible to obtain an adhesive having excellent storage stability. Further, since the moldability and heat resistance are improved, the ratio of the polybasic acid having an aromatic ring or its derivative to the polybasic acid or its derivative is more preferably 50 mol% or more, more preferably 70 mol% or more. More preferably, it is more preferably 96 mol% or more. The polybasic acid or all of its derivatives may be a polybasic acid having an aromatic ring.

Alternatively, the polyester polyol (A1) used in the present invention may be a reaction product of a polybasic acid or a derivative thereof, a polyvalent alcohol and a polyisocyanate, and has an aromatic ring in the polybasic acid or a derivative thereof. The ratio of the polybasic acid or a derivative thereof is preferably 30 mol% or more. This makes it possible to obtain an adhesive having excellent storage stability. Further, since the moldability and heat resistance are improved, the ratio of the polybasic acid having an aromatic ring or its derivative to the polybasic acid or its derivative is more preferably 50 mol% or more, more preferably 70 mol% or more. More preferably, it is more preferably 96 mol% or more. The polybasic acid or all of its derivatives may be a polybasic acid having an aromatic ring.

The hydroxyl value of the polyester polyol (A1) used in the present invention is preferably in the range of 1 to 40 mgKOH / g, more preferably 3 mgKOH / g or more, and 30 mgKOH / g or less because it is superior in adhesive strength. be.

The number average molecular weight (Mn) of the polyester polyol (A1) used in the present invention is preferably in the range of 2,000 to 100,000 because it is superior in adhesive strength when used for adhesive applications. 000 to 50,000 is still preferred. When the number average molecular weight is less than 2,000, the crosslink density in the cured coating film becomes too high, and the appearance and moldability of the laminated body may be deteriorated.
On the other hand, the weight average molecular weight (Mw) is preferably in the range of 5,000 to 300,000, and more preferably in the range of 10,000 to 200,000.

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% by mass in terms of resin solid content Tetrahydrofuran solution filtered through a microfilter (100 μl)

The solid acid value of the polyester polyol (A1) used in the present invention is not particularly limited, but is preferably 10.0 mgKOH / g or less. When it is 5.0 mgKOH / g or less, it is excellent in moisture and heat resistance and is preferable. The lower limit of the solid content acid value is not particularly limited, but is 0.5 mgKOH / g or more as an example. It may be 0 mgKOH / g.

The glass transition temperature of the polyester polyol (A1) used in the present invention is not particularly limited, but is preferably −30 ° C. or higher in order to prevent the adhesive from squeezing out during dry lamination during the production of the laminate. , -20 ° C or higher is more preferable. The upper limit is not particularly limited, but is preferably 110 ° C. or lower in consideration of storage stability and productivity.

The polyester polyol (A1) used in the present invention may contain two or more kinds of polyester polyols having different glass transition temperatures. In this case, it is preferable to include a polyester polyol having a glass transition temperature of −30 ° C. or higher and 20 ° C. or lower, and a polyester polyol having a glass transition temperature of 50 ° C. or higher and 110 ° C. or lower. Thereby, heat resistance and moisture heat resistance can be improved.

The glass transition temperature in the present invention refers to a value measured as follows.
Using a differential scanning calorimetry device (DSC-7000 manufactured by SII Nanotechnology Co., Ltd., 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 stream of 30 mL / min. After that, it is cooled to −80 ° C. at 10 ° C./min. The DSC curve was measured by raising the temperature to 150 ° C at 10 ° C / min again, and the straight line extending the baseline on the low temperature side to the high temperature side in the measurement results observed in the second temperature rise step and the glass transition staircase. The intersection with the tangent line drawn at the point where the slope of the curve of the shaped portion is maximized is defined as the glass transition point, and the temperature at this time is defined as the glass transition temperature. Further, the temperature is raised to 200 ° C. at the first temperature rise, but this may be a temperature at which the polyester polyol (A1) is sufficiently melted, and if 200 ° C. is insufficient, the temperature is appropriately adjusted. Similarly, if the cooling temperature is not sufficient at −80 ° C. (for example, when the glass transition temperature is lower), the cooling temperature is appropriately adjusted.

In synthesizing the polyester polyol (A1), the reaction of the polybasic acid or its derivative with the polyhydric alcohol or the reaction of the polybasic acid or its derivative with the polyhydric alcohol and the polyisocyanate may be carried out by a known method.

For example, the reaction of a polybasic acid or a derivative thereof with the polyhydric alcohol can be carried out by a polycondensation reaction. Further, the reaction of the polybasic acid or its derivative with the polyhydric alcohol and the polyisocyanate requires a polyester polyol obtained by reacting the polybasic acid or its derivative with the polyhydric alcohol by the above method and the polyisocyanate. The polyester polyol (A1) of the present invention can be obtained by reacting in the presence of a known and commonly used urethanization catalyst.

In the esterification reaction of the polybasic acid or its derivative and the polyhydric alcohol, the polybasic acid or its derivative, the polyhydric alcohol and the polymerization catalyst are charged in a reaction vessel equipped with a stirrer and a rectification facility, and the mixture is stirred. The temperature is raised to about 130 ° C. at normal pressure. Then, the generated water is distilled off while raising the temperature at a reaction temperature in the range of 130 to 260 ° C. at a rate of 5 to 10 ° C. per hour. After the esterification reaction for 4 to 12 hours, the polyester polyol (A1) is produced by distilling off excess polyhydric alcohol and accelerating the reaction while gradually increasing the degree of depressurization from normal pressure to the range of 1 to 300 trrr. Can be manufactured.

The polymerization catalyst used in the esterification reaction is composed of at least one metal selected from the group consisting of Group 2, Group 4, Group 12, Group 13, Group 14, and Group 15 of the Periodic Table, or a compound of the metal. A polymerization catalyst is preferred. Examples of the polymerization catalyst composed of such a metal or a metal compound thereof include metals such as Ti, Sn, Zn, Al, Zr, Mg, Hf, and Ge, compounds of these metals, and more specifically, titanium tetraisopropoxide and titanium. Tetrabutoxide, titanium oxyacetylacetonate, tin octanate, 2-ethylhexanetin, acetylacetonate zinc, zirconium tetrachloride, zirconium tetrachloride tetrahydrofuran complex, hafnium tetrachloride, hafnium tetrachloride tetrahydrofuran complex, germanium oxide, tetraethoxygermanium And so on.

Commercially available products of polymerization catalysts that can be used in esterification reactions include Olga Chix TA series, TC series, ZA series, ZC series, AL series manufactured by Matsumoto Fine Chemical Co., Ltd., organic tin catalysts manufactured by Nitto Kasei Co., Ltd., and inorganic metals. Preferred examples include catalysts and inorganic tin compounds.

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, but as an example, a polybasic acid or a derivative thereof and a polyhydric alcohol are not particularly limited. It is 10 to 1000 ppm, preferably 20 to 800 ppm, based on the total amount of and. In order to suppress the coloring of the polyester polyol (A1), it is more preferably 30 to 500 ppm.

Further, the polyester polyurethane polyol used in the present invention is obtained by chain-extending the polyester polyol obtained by the above-mentioned method with polyisocyanate. As a specific production method, a polyester polyol, a polyisocyanate, a chain extension catalyst, and a good solvent of the polyester polyol and the polyisocyanate used as needed are charged in a reaction vessel, and the reaction temperature is 60 to 90 ° C. Stir with. The reaction is carried out until the isocyanate group derived from the polyisocyanate used is substantially eliminated to obtain the polyester polyurethane polyol used in the present invention.

As the chain extension catalyst, a known public catalyst used as a normal urethanization catalyst can be used. Specific examples thereof include organic tin compounds, organic carboxylic acid tin salts, lead carboxylates, bismuth carboxylates, titanium compounds, zirconium compounds and the like, which can be used alone or in combination. The amount of the chain extension catalyst used may be an amount that sufficiently promotes the reaction between the polyester polyol and the polyisocyanate, and specifically, 5.0 mass by mass with respect to the total amount of the polyester polyol and the polyisocyanate. % Or less is preferable. In order to suppress hydrolysis and coloring of the resin by the catalyst, 1.0% by mass or less is more preferable. Further, these chain extension catalysts may be used in consideration of the action of the polyol composition (A) and the isocyanate composition (B), which will be described later, as a curing catalyst.

As a method for confirming the remaining amount of isocyanate groups, confirmation of the presence or absence of an absorption peak observed near 2260 cm ^-1 , which is an absorption spectrum derived from isocyanate groups, by infrared absorption spectrum measurement, and determination of isocyanate groups by a titration method. Can be mentioned.

Examples of the good solvent used for producing the polyester polyurethane polyol include ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, propylene glycol monomethyl ether acetate, toluene, xylene and the like. It may be used alone or in combination of two or more.

(Polyisocyanate composition (B))
The polyisocyanate composition (B) used in the present invention contains an isocyanate compound (B1) and an isocyanate compound (B2). Further, the isocyanate compound (B1) contains an aromatic polyisocyanate, and the isocyanate compound (B2) contains at least one selected from the group consisting of diphenylmethane diisocyanate and carbodiimide-modified products of diphenylmethane diisocyanate. In the present invention, the aromatic polyisocyanate (B1) does not contain diphenylmethane diisocyanate (B2). Polyisocyanate composition (B) If necessary, other isocyanate compounds may be contained.

The isocyanate compound (B1) is a compound in which an isocyanate group is directly bonded to an aromatic ring, and specifically, 1,5-naphthylene diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, and 4,4'-dibenzyldiisocyanate. , Dialkyl diphenylmethane diisocyanate, Tetraalkyl diphenylmethane diisocyanate, 1,3-phenylenediisocyanate, 1,4-phenylenediisocyanate, Toluene diisocyanate and other aromatic diisocyanides, these diisocyanides and 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate , 4,4'-Diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate oligomer, adduct-type polyisocyanate compound, nurate-type polyisocyanate compound, and the like. This makes it possible to obtain an adhesive having excellent heat resistance and moisture heat resistance.

The isocyanate compound (B1) may be a compound having two isocyanate groups in one molecule, but a compound having three or more isocyanate groups in one molecule is more preferable. Among them, it is preferable to use toluene diisocyanate and derivatives of toluene diisocyanate (toluene diisocyanate oligomer, adduct-type polyisocyanate compound, nurate-type polyisocyanate compound), and it is more preferable to use toluene diisocyanate adduct-type polyisocyanate compound. It is more preferable to use an adduct compound with trimethylol propane. The toluene diisocyanate may be either 2,4-toluene diisocyanate or 2,6-toluene diisocyanate alone or a mixture.

The isocyanate compound (B2) is a carbodiimide-modified diphenylmethane diisocyanate obtained by condensing 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, and at least one of these diphenylmethane diisocyanates in the presence of a catalyst. Any one may be used alone, or any two or more kinds may be used in combination. It is preferable to contain 4,4'-diphenylmethane diisocyanate because it is excellent in workability.

The other isocyanate compound (B3) is not particularly limited as long as it is a compound having two or more isocyanate groups in one molecule, and various compounds can be used. Specifically, various diisocyanate compounds exemplified as the raw materials of the polyester polyol (A1) described above, adduct-modified diisocyanate compounds obtained by reacting various diisocyanate compounds with diol compounds, biuret-modified products and allophanate-modified products thereof. Alternatively, various trifunctional or higher polyisocyanate compounds can be used, and they may be used alone or in combination of two or more.

(Adhesive and other ingredients)
The adhesive of the present invention can be used in combination with other components as long as the effects of the present invention are not impaired. For example, the polyol composition (A) preferably contains a polycarbonate polyol compound in addition to the polyester polyol (A1). At this time, the total amount of the polyester polyol (A1) and the compounding ratio of the polycarbonate polyol compound are high in adhesiveness to various base materials and excellent in moisture and heat resistance, so that the polyester polyol is relative to the total mass of both. The total mass of (A1) is preferably in the range of 30 to 99.5% by mass, and preferably in the range of 60 to 99% by mass.

The number average molecular weight (Mn) of the polycarbonate polyol compound is preferably in the range of 300 to 2,000 because it is an adhesive having high adhesiveness to various substrates and excellent moisture and heat resistance. The hydroxyl value is preferably in the range of 30 to 250 mgKOH / g, more preferably in the range of 40 to 200 mgKOH / g. Further, the polycarbonate polyol compound is preferably a polycarbonate diol compound.

Further, the polyol composition (A) preferably contains a polyoxyalkylene modified polyol compound in addition to the polyester polyol (A1). At this time, the total amount of the polyester polyol (A1) and the blending ratio of the polyoxyalkylene-modified polyol compound are high in adhesiveness to various substrates and excellent in moisture and heat resistance. On the other hand, the total mass of the polyester polyol (A1) is preferably in the range of 30 to 99.5% by mass, preferably in the range of 60 to 99% by mass.

The number average molecular weight (Mn) of the polyoxyalkylene-modified polyol compound is preferably in the range of 300 to 2,000 because it is an adhesive having high adhesiveness to various substrates and excellent moisture and heat resistance. The hydroxyl value is preferably in the range of 40 to 250 mgKOH / g, more preferably in the range of 50 to 200 mgKOH / g. Further, the polyoxyalkylene-modified polyol compound is preferably a polyoxyalkylene-modified diol compound.

The polyol composition (A) used in the present invention may contain other resin components in addition to the polyester polyol (A1). When other resin components are used, it is preferably used in an amount of 50% by mass or less, preferably 30% by mass or less, based on the total mass of the main agent. Specific examples of other resin components include epoxy resins. The epoxy resin is, for example, a bisphenol type epoxy resin such as a bisphenol A type epoxy resin or a bisphenol F type epoxy resin; a biphenyl type epoxy resin such as a biphenyl type epoxy resin or a tetramethyl biphenyl type epoxy resin; a dicyclopentadiene-phenol addition reaction. Examples include type epoxy resins. These may be used alone or in combination of two or more. Among these, it is preferable to use a bisphenol type epoxy resin because it is an adhesive having high adhesiveness to various base materials and excellent moisture and heat resistance.

The number average molecular weight (Mn) of the epoxy resin is preferably in the range of 300 to 2,000 because it is an adhesive having high adhesiveness to various substrates and excellent moisture and heat resistance. The epoxy equivalent is preferably in the range of 150 to 1000 g / equivalent.

When the epoxy resin is used, the total amount of the polyester polyol (A1) and the compounding ratio of the epoxy resin are high in adhesiveness to various base materials and excellent in moisture and heat resistance. On the other hand, the total mass of the polyester polyol (A1) is preferably in the range of 30 to 99.5% by mass, preferably in the range of 60 to 99% by mass.

The polyol composition (A) used in the present invention may contain a tackifier. Examples of the tackifier include a rosin-based or rosin ester-based tackifier, a terpene-based or terpene-phenol-based tackifier, a saturated hydrocarbon resin, a kumaron-based tackifier, a kumaron inden-based tackifier, and a styrene resin-based adhesive. Examples thereof include a tackifier, a xylene resin-based tackifier, a phenol-resin-based tackifier, a petroleum resin-based tackifier, and a ketone resin-based tackifier. Ketone resin-based tackifiers, rosin-based or rosin ester-based tackifiers are preferable, and ketone resin-based tackifiers are more preferable. These may be used alone or in combination of two or more. When the tackifier is used, the total mass of the polyester polyol (A1) is preferably 80 to 99.99 mass%, preferably 85 to 99.9 mass%, based on the total mass of the polyester polyol (A1) and the tackifier. % Is more preferable.

Examples of the rosin-based or rosin ester-based rosin are polymerized rosins, disproportionated rosins, hydrogenated rosins, maleated rosins, fumarized rosins, and their glycerin esters, pentaerythritol esters, methyl esters, ethyl esters, butyl esters, and ethylene glycols. Examples thereof include esters, diethylene glycol esters, and triethylene glycol esters.

Examples of the terpene type or the terpene phenol type include a low-polymerized terpene type, an α-pinene polymer, a β-pinene polymer, a terpene phenol type, an aromatic-modified terpene type, and a hydrogenated terpene type.

Petroleum resin-based products include petroleum resins obtained by polymerizing petroleum fractions having 5 carbon atoms obtained from penten, pentadiene, isoprene, etc., inden, methylinden, vinyltoluene, styrene, α-methylstyrene, β-methylstyrene, etc. Petroleum resin obtained by polymerizing a petroleum fraction having 9 carbon atoms, C5-C9 copolymerized petroleum resin obtained from the various monomers, petroleum resin obtained by hydrogenating these, cyclopentadiene, and petroleum resin obtained from dicyclopentadiene; Also, hydrides of those petroleum resins; modified petroleum resins obtained by modifying those petroleum resins with maleic anhydride, maleic acid, fumaric acid, (meth) acrylic acid, phenol and the like can be exemplified.

As the phenol resin system, a condensate of phenols and formaldehyde can be used. Examples of the phenols include phenol, m-cresol, 3,5-xylenol, p-alkylphenol, resorcin and the like, and these phenols and formaldehyde are subjected to an addition reaction with an alkali catalyst, or a condensation reaction with an acid catalyst. The obtained novolak and the like can be exemplified. Further, a rosin phenol resin obtained by adding phenol to rosin with an acid catalyst and thermally polymerizing it can also be exemplified.

Examples of the ketone resin include known and commonly used ones, but formaldehyde resin, cyclohexanone / formaldehyde resin, ketone aldehyde condensed resin and the like can be preferably used.

A tackifier having various softening points can be obtained, but the softening point is 70 in terms of compatibility, color tone, thermal stability, etc. when mixed with other resins constituting the polyol composition (A). A ketone resin-based pressure-sensitive adhesive having a softening point of about 160 ° C., preferably 80 to 100 ° C., or a rosin-based resin having a softening point of 80 to 160 ° C., preferably 90 to 110 ° C. and a hydrogenated derivative thereof are preferable, and the softening point is 70 to 70. A ketone resin-based tackifier at 160 ° C., preferably 80 to 100 ° C. is more preferable. Further, a ketone resin-based tackifier having an acid value of 2 to 20 mgKOH / g and a hydroxyl value of 10 mgKOH / g or less, or a hydrogenated rosin-based tackifier is preferable, and the acid value is 2 to 20 mgKOH / g and the hydroxyl value is A ketone tackifier of 10 mgKOH / g or less is more preferable.

In the adhesive of the present invention, as yet another good embodiment, known phosphoric acids or derivatives thereof can be used in combination. As a result, the initial adhesiveness of the adhesive is further improved, and troubles such as tunneling can be solved.

Examples of the phosphoric acid used here or a derivative thereof include phosphoric acids such as hypophosphoric acid, phosphoric acid, orthophosphoric acid, and hypophosphoric acid, such as metaphosphoric acid, pyrophosphoric acid, tripolyphosphoric acid, polyphosphoric acid, and ultraphosphoric acid. Condensed Phosphoric Acids such as, for example, monomethyl orthophosphoric acid, monoethyl orthophosphoric acid, monopropyl orthophosphoric acid, monobutyl orthophosphate, mono-2-ethylhexyl orthophosphate, monophenyl orthophosphoric acid, monomethyl phosphite, monoethyl phosphite, phosphite. Monopropyl, monobutyl phosphite, mono-2-ethylhexyl phosphite, monophenyl phosphite, di-2-ethylhexyl orthophosphate, dimethyl diphenyl phosphite, diethyl phosphite, dipropyl phosphite, sub Monos such as dibutyl phosphate, di-2-ethylhexyl phosphite, diphenyl phosphite, diesterates, monos from condensed phosphoric acid and alcohols, diesterates, such as the above phosphoric acids, such as ethylene oxide and propylene oxide. Examples thereof include those to which an epoxy compound such as is added, for example, epoxy phosphoric acid esters obtained by adding the above-mentioned phosphoric acid to an aliphatic or aromatic diglycidyl ether.

The above-mentioned phosphoric acids or derivatives thereof may be used alone or in combination of two or more. As a method of containing it, it is sufficient to simply mix it.

In addition, an adhesion promoter can also be used in the adhesive of the present invention. Examples of the adhesion accelerator include a silane coupling agent, a titanate-based coupling agent, an aluminum-based coupling agent, an epoxy resin, and the like.

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 and N-phenyl-γ-aminopropyltrimethoxysilane; β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-gly Epoxysilanes such as sidoxylpropyltriethoxysilane; vinylsilanes such as vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane; hexamethyldisilazane, γ-mercapto Propyltrimethoxysilane and the like can be mentioned.

Examples of the titanate-based coupling agent include tetraisopropoxytitanium, tetra-n-butoxytitanium, butyl titanate dimer, tetrastearyl titanate, titanium acetylacetonate, titanium lactate, tetraoctylene glycol titanate, titanium lactate, and tetrastealoxy. Titanium and the like can be mentioned.

Moreover, as an aluminum-based coupling agent, for example, acetalkoxyaluminum diisopropyrate and the like can be mentioned.

It is preferable to use a silane coupling agent as the adhesion accelerator. The content (solid content) of the adhesion accelerator is preferably 0.1 part by mass or more, and preferably 0.3 part by mass or more with respect to 100 parts by mass of the solid content of the polyol composition (A). It is more preferably 0.5 parts by mass or more, further preferably 0.7 parts by mass or more. 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 5 parts by mass with respect to 100 parts by mass of the solid content of the polyol composition (A). More preferably, it is less than or equal to a portion.

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

Further, 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 [NCO'] of isocyanate groups contained in the isocyanate compound (B2) is 1. It is preferably 5 or less, and more preferably 1.3 or less. The lower limit of [NCO'] / [OH] is not particularly limited, but it is preferably 0.3 or more, preferably 0.5 or more, in order to surely improve the adhesive strength, moldability, heat resistance, and moisture heat resistance. Is more preferable.

The reason why the adhesive of the present invention is excellent in moldability, heat resistance, and moisture heat resistance is not clear, but it is presumed as follows. Considering the polyisocyanate composition (B), if the reactivity of the isocyanate compound is low, the unreacted isocyanate compound may remain in the coating film. The residual isocyanate compound acts like a pseudoplasticizer and causes a decrease in heat resistance of the cured coating film. On the other hand, if the reactivity of the isocyanate compound is too high, the cured coating film becomes too hard and the moldability deteriorates. Further, the reaction between the polyol composition (A) and the polyisocyanate composition (B) may proceed before it gets wet and spreads on the substrate, and the adhesive strength may decrease.

The isocyanate compounds (B1) and (B2) have high reactivity of the first isocyanate group, and there is little possibility that a large amount of the isocyanate compounds (B1) and (B2) remain in the cured coating film in an unreacted state. The reactivity of the second isocyanate group is sufficiently slower than that of the first isocyanate group for both the isocyanate compounds (B1) and (B2), and the isocyanate compound (B1) is significantly slower than that of (B2). slow. It is considered that when these isocyanate compounds are used in combination, the reaction gradually proceeds at an appropriate rate during the aging process, and the crosslinked structure can withstand molding at around room temperature while maintaining the adhesive strength in a high temperature range.

The present invention is particularly effective for an adhesive using the polyol composition (A) having a relatively high surface tension. Various factors affect the surface tension of a compound. For example, the polyester polyol (A1) having a glass transition temperature and the polyester polyol (A1) having an aromatic ring incorporated in the main skeleton as described above are substrates at around room temperature. It is hard to get wet and spread. In the present invention, the polyol composition (A) is mixed with the polyisocyanate composition (B), coated, and immediately after the substrates are bonded to each other (before the aging step), the substrate is not sufficiently wetted and spread. Even in such a case, by heating in the aging step, the coating spreads and the cross-linking reaction proceeds to develop the adhesive ability.

The adhesive of the present invention may be in either a solvent type or a solventless type. The "solvent type" adhesive referred to in the present invention means that the adhesive is applied to a base material and then heated in an oven or the like to volatilize the organic solvent in the coating film and then bonded to another base material. A method, a form used in the so-called dry laminating method. Either one or both of the polyol composition (A) and the polyisocyanate composition (B) can dissolve the polyol composition (A) or the polyisocyanate composition (B) used in the present invention. Contains highly soluble organic solvent. In the case of the solvent type, the organic solvent used as a reaction medium in the production of the constituent components of the polyol composition (A) or the polyisocyanate composition (B) may be further used as a diluent during painting. Examples of the highly soluble organic solvent include esters such as ethyl acetate, butyl acetate and cellosolve acetate, ketones such as acetone, methyl ethyl ketone, isobutyl ketone and cyclohexanone, ethers such as tetrahydrofuran and dioxane, and fragrances such as toluene and xylene. Examples thereof include group hydrocarbons, halogenated hydrocarbons such as methylene chloride and ethylene chloride, dimethylsulfoxide, dimethylsulfamide and the like.

As used herein, the "solvent-free" adhesive is substantially the highly soluble organic solvent as described above in the polyol composition (A) and the polyisocyanate composition (B), particularly ethyl acetate or methyl ethyl ketone. A form of adhesive used in the so-called non-solvent laminating method, which is a method in which an adhesive is applied to a base material and then bonded to another base material without a step of heating in an oven or the like to volatilize the solvent. Point to. The constituent components of the polyol composition (A) or the polyisocyanate composition (B) and the organic solvent used as the reaction medium in the production of the raw material thereof could not be completely removed, and the polyol composition (A) or the polyisocyanate composition (A) or the polyisocyanate composition ( If a small amount of organic solvent remains in B), it is understood that the organic solvent is not substantially contained. Further, when the polyol composition (A) contains a low molecular weight alcohol, the low molecular weight alcohol reacts with the polyisocyanate composition (B) and becomes a part of the coating film, so that it is not necessary to volatilize after coating. Therefore, such a form is also treated as a solvent-free adhesive.

When the adhesive of the present invention is of the solvent type, the viscosity can be reduced by diluting the solvent, so that the polyol composition (A) or the polyisocyanate composition (B) to be used can be used even if it has a slightly high viscosity. .. On the other hand, in the case of the solvent-free type, low viscosity is emphasized due to the characteristic of lowering the viscosity by heating, and as a means for lowering the viscosity, the polyisocyanate composition (B) reduces the aromatic concentration that contributes to the viscosity. Things are often used.

Even if the adhesive of the present invention contains various additives such as an ultraviolet absorber, an antioxidant, a silicon-based additive, a fluorine-based additive, a rheology control agent, a defoaming agent, an antistatic agent, and an antifogging agent. good.

The use of the adhesive of the present invention is not particularly limited, but it can be suitably used as a packaging material for batteries as an example because it is excellent in adhesive strength, processability, moisture heat resistance, and heat resistance.

<Laminated body>
The laminate of the present invention is obtained by laminating a plurality of base materials by a dry laminating method or a non-solvent laminating method using the adhesive of the present invention. As the base material, paper, olefin resin, acrylonitrile-butadiene-styrene copolymer (ABS resin), polyvinyl chloride resin, fluororesin, poly (meth) acrylic resin, carbonate resin, polyamide resin, etc. Examples thereof include polyimide resins, polyphenylene ether resins, synthetic resin films obtained from polyphenylene sulfide resins and polyester resins, copper foils, metal foils such as aluminum foils, and the like.

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

<Battery packaging material>
As shown in FIG. 1, the battery packaging material is composed of at least 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 sequentially laminated. In the battery packaging material of the present invention, the outer layer side base material layer 1 is the outermost layer, and the sealant layer 4 is the innermost layer. That is, at the time of assembling the battery, the sealant layers 4 located on the peripheral edge of the battery element are heat-sealed to seal the battery element, whereby the battery element is sealed. The adhesive of the present invention is used for the adhesive layer 2. Further, in the battery packaging material of the present invention, as shown in FIG. 2, an adhesive layer 5 is provided between the metal layer 3 and the sealant layer 4 as needed for the purpose of enhancing their adhesiveness. You may.

(Outer layer side base material layer 1)
In the battery packaging material of the present invention, the outer layer side base material layer 1 is a layer forming the outermost layer. The material forming the outer layer side base material layer 1 is not particularly limited as long as it has insulating properties, and polyester resin, polyamide resin, epoxy resin, acrylic resin, fluororesin, polyurethane resin, silicon resin, phenol resin, etc. And resin films such as a mixture thereof and a copolymer thereof. 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, polycarbonate and the like. Specific examples of the polyamide resin include nylon 6, nylon 6,6, a copolymer of nylon 6 and nylon 6,6, nylon 6,10, polymethoxylylen adipamide (MXD6), and the like. Be done.

The outer layer side base material layer 1 may be formed of one layer of resin film, but in order to improve pinhole resistance and insulating property, it is made of two or more layers of resin film, for example, a polyethylene terephthalate film and a polyamide film. It may be formed of a plurality of layers. When the outer layer side base material layer 1 is formed of a multilayer resin film, the resin films may be laminated via an adhesive component such as an adhesive or an adhesive resin, and the type and amount of the adhesive component used may be used. The same applies to the case of the adhesive layer 2 or the adhesive layer 5 described later. The method for laminating two or more layers of resin films is not particularly limited, and a known method can be adopted. Examples thereof include a dry lamination method and a sand lamination method, and a dry lamination method is preferable. When laminating by the dry lamination method, it is preferable to use an adhesive as an adhesive layer. At this time, the thickness of the adhesive layer is, for example, about 0.5 to 10 μm.

The thickness of the outer layer side base material layer 1 is not particularly limited as long as the battery packaging material satisfies the above physical characteristics, but 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 can be secured as a packaging material, stress during overhang molding and drawing molding can be reduced, and formability can be improved.

(Metal layer 3)
In the battery packaging material, the metal layer 3 is a layer that functions as a barrier layer for improving the strength of the battery packaging material and preventing water vapor, oxygen, light, and the like from entering the inside of the battery. Specific examples of the metal constituting the metal layer 3 include aluminum, stainless steel, titanium, and the like, and aluminum is preferable. The metal layer 3 can be formed by a metal foil, metal vapor deposition, or the like, and is preferably formed of a metal foil, and more preferably formed of an aluminum foil. Further, it is preferable that at least one surface, preferably both sides, of the metal layer 3 is subjected to chemical conversion treatment in order to stabilize adhesion, prevent dissolution and corrosion, and the like. Here, the chemical conversion treatment refers to a treatment for forming an acid-resistant film on the surface of the metal layer.

The thickness of the metal layer 3 is not particularly limited as long as the battery packaging material satisfies the above physical characteristics, but can be, for example, about 10 to 50 μm, preferably about 25 to 45 μm.

(Sealant layer 4)
In the battery packaging material of the present invention, the sealant layer 4 corresponds to the innermost layer, and is a layer in which the sealant layers are heat-sealed to seal the battery element when the battery is assembled.

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

Specific examples of the polyolefin include polyethylene such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; homopolypropylene, a block copolymer of polypropylene (for example, a block copolymer of propylene and ethylene), and polypropylene. Polypropylene such as random copolymers of polyethylene (eg, random copolymers of propylene and ethylene); polyethylene-butene-propylene tarpolymers; and the like. Among these polyolefins, polyethylene and polypropylene are preferable.

The cyclic polyolefin is a copolymer of an olefin and a cyclic monomer, and examples of the olefin which is a constituent monomer of the cyclic polyolefin include ethylene, propylene, 4-methyl-1-pentene, styrene, butadiene, isoprene, and the like. Can be mentioned. Examples of the cyclic monomer which is a constituent monomer of the cyclic polyolefin include cyclic alkenes such as norbornene; specifically, cyclic diene such as cyclopentadiene, dicyclopentadiene, cyclohexadiene, norbornadiene and the like. Among these polyolefins, cyclic alkene is preferable, and norbornene is more preferable.

The carboxylic acid-modified polyolefin is a polymer modified 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, itaconic anhydride and the like.

The carboxylic acid-modified cyclic polyolefin means that a part of the monomer constituting the cyclic polyolefin is copolymerized in place of α, β-unsaturated carboxylic acid or its anhydride, or α, β with respect to the cyclic polyolefin. -A polymer obtained by block polymerization or graft polymerization of unsaturated carboxylic acid or its anhydride. The same applies to the cyclic polyolefin that is modified with carboxylic acid. The carboxylic acid used for modification is the same as that used for modification of the acid-modified cycloolefin copolymer.

The sealant layer 4 may be formed by one kind of resin component alone, or may be formed by a blend polymer in which two or more kinds of resin components are combined. Further, the sealant layer 4 may be formed of only one layer, but may be formed of two or more layers with the same or different resin components.

The thickness of the sealant layer 4 is not particularly limited as long as the battery packaging material satisfies the above physical characteristics, but is, for example, about 10 to 100 μm, preferably about 20 to 90 μm.

(Adhesive layer 5)
In the packaging material for a battery 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 bond the metal layer 3 and the sealant layer 4.

The adhesive layer 5 is formed of an adhesive capable of adhering the metal layer 3 and the sealant layer 4. Examples of the adhesive layer used for the adhesive layer 5 include an adhesive in which a polyolefin resin and a polyfunctional isocyanate are combined, an adhesive in which a polyol and a polyfunctional isocyanate are combined, a modified polyolefin resin, a heterocyclic compound and a curing agent. The adhesive contained can be used. Alternatively, an adhesive such as acid-modified polypropylene is melt-extruded onto a metal layer with a T-die extruder to form an adhesive layer 5, a sealant layer 4 is superposed on the adhesive layer 5, and the metal layer 3 and the sealant layer 4 are formed. Can also be pasted together.
If both the adhesive layer 2 and the adhesive layer 5 require aging, they can be aged together. By setting the aging temperature to room temperature to 90 ° C., curing is completed in 2 days to 2 weeks, and formability is exhibited.

The thickness of the adhesive layer 5 is not particularly limited as long as the battery packaging material satisfies the above physical characteristics, but is, for example, about 0.5 to 50 μm, preferably about 2 to 30 μm.

(Coating layer 6)
In the packaging material for a battery of the present invention, for the purpose of improving designability, electrolytic solution resistance, scratch resistance, moldability, etc., as necessary, above the outer layer side base material layer 1 (outer layer side base material layer). The coating layer 6 may be provided on the side opposite to the metal layer 3 of 1. The coating layer 6 is a layer located on the outermost layer when the battery is assembled.

The coating layer 6 can be formed of, for example, polyvinylidene chloride, polyester resin, urethane resin, acrylic resin, epoxy resin, or the like, and is preferably formed of a two-component curable resin. Examples of the two-component curable resin forming the coating layer 6 include a two-component curable urethane resin, a two-component curable polyester resin, and a two-component curable epoxy resin. Further, the coating layer 6 may contain a matting agent.

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, 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 Examples thereof include nylon, cross-linked acrylic, cross-linked styrene, cross-linked 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, silica, barium sulfate, and titanium oxide are preferable from the viewpoint of dispersion stability and cost. Further, the matting agent may be subjected to various surface treatments such as insulation treatment and high dispersibility treatment on the surface.

The method for forming the coating layer 6 is not particularly limited, and examples thereof include a method of applying a two-component curable resin for forming the coating layer 6 on one surface of the outer layer side base material layer 1. When the matting agent is blended, the matting agent may be added to the two-component curable resin, mixed, and then applied.

(Manufacturing method of packaging materials for batteries)
The method for producing the packaging material for a battery of the present invention is not particularly limited as long as a laminated body in which each layer having a predetermined composition is laminated can be obtained, but the following methods are exemplified.

First, a laminated body in which the outer layer side base material layer 1, the adhesive layer 2, and the metal layer 3 are laminated in this order (hereinafter, may be referred to as “laminated body A”) is formed. To form the laminate A, specifically, the adhesive of the present invention is extruded on the outer layer side base material layer 1 or on the metal layer 3 whose surface has been chemically converted as needed, by an extrusion method, a gravure coating method, or a roll. It can be carried out by a dry lamination method in which the metal layer 3 or the outer layer side base material layer 1 is laminated and the adhesive layer 2 is cured after being applied and dried by a coating method such as a coating method.

Next, the sealant layer 4 is laminated on the metal layer 3 of the laminated body A. When the sealant layer 4 is directly laminated on the metal layer 3, the resin component constituting the sealant layer 4 may be applied onto the metal layer 3 of the laminated body A by a method such as a gravure coating method or a roll coating method. .. When the adhesive layer 5 is provided between the metal layer 3 and the sealant layer 4, for example, a method of co-extruding the adhesive layer 5 and the sealant layer 4 onto the metal layer 3 of the laminated body A (the method of laminating them). Coextruding lamination method), a method of separately forming a laminated body in which an adhesive layer 5 and a sealant layer 4 are laminated and laminating this on the metal layer 3 of the laminated body A by a thermal lamination method, or a method of laminating the metal of the laminated body A. An adhesive for forming an adhesive layer 5 is laminated on the layer 3 by an extrusion method, a solution-coated high-temperature drying method, a baking method, or the like, and a sheet-like film is formed on the adhesive layer 5 in advance. Is laminated by a thermal lamination method, or between the metal layer 3 of the laminated body A and the sealant layer 4 which has been formed into a sheet in advance, the melted adhesive layer 5 is poured through the adhesive layer 5. Examples thereof include a method of laminating the laminate A and the sealant layer 4 (sand lamination method).

When the coating layer 6 is provided, the coating layer 6 is laminated on the surface of the outer layer side base material layer 1 opposite to the metal layer 3. The coating layer 6 is formed by applying, for example, the above resin forming the coating layer 6 to the surface of the outer layer side base material layer 1. The order of the step of laminating the metal layer 3 on the surface of the outer layer side base material layer 1 and the step of laminating the coating layer 6 on the surface of the outer layer side base material layer 1 is not particularly limited. For example, after forming the coating layer 6 on the surface of the outer layer side base material layer 1, the metal layer 3 may be formed on the surface of the outer layer side base material layer 1 on the opposite side to the coating layer 6.

As described above, the coating layer 6 provided as needed / the outer layer side base material layer 1 / the adhesive layer 2 / the metal layer whose surface is chemically treated as needed 3 / the adhesive layer 5 provided as needed. / A laminate composed of the sealant layer 4 is formed, but in order to strengthen the adhesiveness of the adhesive layer 2 and the adhesive layer 5 provided as needed, a hot roll contact type, a hot air type, near or far type is further formed. It may be subjected to heat treatment such as infrared type. Examples of the conditions for such heat treatment include 1 to 5 minutes at 150 to 250 ° C.

In the packaging material for batteries of the present invention, each layer constituting the laminated body improves or stabilizes film forming property, laminating process, suitability for secondary processing (pouching, embossing) of the final product, etc., as necessary. Therefore, surface activation treatments such as corona treatment, blast treatment, oxidation treatment, and ozone treatment may be performed.

<Battery container>
The battery container of the present invention can be obtained by using the above-mentioned battery packaging material and molding the outer layer side base material layer 1 so as to form a convex surface and the sealant layer 4 to form a concave surface.
As a method for molding the concave portion, there are the following methods.
・ Heat-pressed air molding method: A battery packaging material is sandwiched between a lower mold with holes to supply high-temperature, 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 battery packaging material, air is supplied by sandwiching it between a lower mold with a hole for supplying high-pressure air and an upper mold with a pocket-shaped recess. How to form 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 battery packaging material, air is supplied by sandwiching it between a lower mold with a hole for supplying high-pressure air and an upper mold with a pocket-shaped recess. A method of forming a concave portion, which assists molding by raising and lowering a convex plug during molding.

Above all, the preheater plug assist compressed air molding method, which is a heating vacuum forming method, is preferable in that the wall thickness of the bottom material after molding can be uniformly obtained.

(Use of battery packaging material)
The battery packaging material of the present invention is used as a battery container for sealing and accommodating battery elements such as a positive electrode, a negative electrode, and an electrolyte.

Specifically, a battery element having at least a positive electrode, a negative electrode, and an electrolyte is made of the battery packaging material of the present invention in a state where metal terminals connected to each of the positive electrode and the negative electrode are projected outward. A battery using a battery packaging material can be 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 to seal each other. Provided. When the battery element is housed using the battery packaging material of the present invention, the sealant portion of the battery packaging material of the present invention is used so as to be inside (the surface in contact with the battery element).

The battery packaging material of the present invention may be used for either a primary battery or a secondary battery, but is preferably used for a secondary battery. The type of the secondary battery to which the battery packaging material of the present invention is applied 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 / Examples thereof include iron storage batteries, nickel / zinc storage batteries, silver oxide / zinc storage batteries, metal air batteries, polyvalent 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 in more detail with reference to specific synthetic examples and examples, but the present invention is not limited to these examples. In the following examples, "parts" and "%" represent "parts by mass" and "% by mass", respectively, unless otherwise specified.

<Adjustment of polyester polyol>
(Synthesis Example 1) Synthesis of polyester polyol (A1) 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, neopentyl glycol 107 . Polyester polyol was synthesized according to a conventional method using 4 parts. The obtained polyester polyol is diluted with ethyl acetate to a resin solid content of 58%, and has a number average molecular weight (Mn) of 7,900, a weight average molecular weight (Mw) of 25,700, and a resin hydroxyl value (in terms of solid content). A polyester polyol (A1) having a resin acid value (in terms of solid content) of 0.82 mgKOH / g and a glass transition temperature (Tg) of 7.3 ° C. was obtained at 22.2 mgKOH / g.

(Synthesis Example 2) Synthesis of polyester polyol (A2) 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, neopentyl glycol 107 . Polyester polyol was synthesized according to a conventional method using 4 parts. The obtained polyester polyol is diluted with ethyl acetate to a resin solid content of 58%, and has a number average molecular weight (Mn) of 7,000, a weight average molecular weight (Mw) of 23,500, and a resin hydroxyl value (in terms of solid content). A polyester polyol (A2') having a resin acid value (in terms of solid content) of 1.26 mgKOH / g and a glass transition temperature (Tg) of 2.1 ° C. was obtained at 22.4 mgKOH / g.

A chain extension reaction was carried out using 900 parts of polyester polyol (A2') and 13.47 parts of hexamethylene diisocyanate. The reaction was stopped when the isocyanate weight% was 0.25% or less, and the resin solid content was diluted to 40% with ethyl acetate to have a number average molecular weight (Mn) of 13,700 and a weight average molecular weight (Mw). A polyester polyol (A2) having a resin hydroxyl value of 7.6 mgKOH / g, a resin acid value of 1.35 mgKOH / g, and a glass transition temperature point (Tg) of 9.9 ° C. was obtained.

(Synthesis Example 3) Synthesis of polyester polyol (A3) A polyester polyol was obtained using 697.2 parts of terephthalic acid, 72.9 parts of ethylene glycol, and 229.9 parts of 1,2-propylene glycol according to a conventional method. The obtained polyester polyol is diluted with methyl ethyl ketone to a resin solid content of 30%, and the number average molecular weight (Mn) is 8,400, the weight average molecular weight (Mw) is 61,300, and the resin hydroxyl value (solid content conversion) is 5. A polyester polyol (A3) having a resin acid value (in terms of solid content) of 4.0 mgKOH / g and a glass transition temperature of 84 ° C. was obtained at 0.0 mgKOH / g.

The physical characteristics of the polyester polyol were measured as follows.
(Molecular weight measurement method)
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% by mass in terms of resin solid content Tetrahydrofuran solution filtered through a microfilter (100 μl)

(Acid value measurement method)
5.0 g of the sample was precisely weighed, dissolved by adding 30 mL of a neutral solvent, and titrated with a 0.1 mol / L potassium hydroxide solution (methanolic). Phenolphthalein was used as an indicator. The measurement result was converted into the amount of potassium hydroxide required to neutralize 1 g of the sample, and the unit was mgKOH / g.

(Measurement method of hydroxyl value)
4.0 g (solid content equivalent) of the sample was precisely weighed, 25 mL of an acetylating agent consisting of acetic anhydride / pyridine (volume ratio 1/19) was added, the sample was sealed, and the mixture was heated at 100 ° C. for 1 hour. After acetylation, 10 mL of ion-exchanged water and 100 mL of tetrahydrofuran were added, and titration was performed using a 0.5 mol / L potassium hydroxide solution (alcoholic). Phenolphthalein was used as an indicator. The measurement result was converted into the amount of potassium hydroxide required to neutralize the acetic acid generated when 1 g of the sample was acetylated, and the unit was mgKOH / g.

(Glass transition temperature measurement method)
5 mg of the sample was heated from room temperature to 200 ° C. at 10 ° C./min under a nitrogen stream of 30 mL / min using DSC, cooled to -80 ° C. at 10 ° C./min, and then 10 ° C./to 150 ° C. again. The temperature was raised in min and the DSC curve was measured. In the measurement results observed in the second temperature rise step, the straight line extending the baseline on the low temperature side to the high temperature side and the tangent line drawn at the point where the slope of the curve of the stepped part of the glass transition is maximized. The intersection of the above was defined as the glass transition point, and the temperature at this time was defined as the glass transition temperature.

<Adhesive adjustment>
(Example 1)
KBM-403 (silane coupling agent non-volatile content manufactured by Shin-Etsu Chemical Co., Ltd .: 100%) was added to the polyester polyol (A1), and the mixture was stirred well until KBM-403 was completely dissolved. Here, isocyanate (B1-1) and isocyanate (B2-1) were added, ethyl acetate was further added so that the non-volatile content was 25%, and the mixture was stirred well to prepare the adhesive of Example 1. Table 1 shows the blending amount (solid content) of each component in the adhesive of Example 1.

(Example 2) to (Example 6)
The adhesives of Examples 2 to 6 were produced in the same manner as in Example 1 except that the materials and formulations used for adjusting the adhesive were adjusted to the values shown in Table 1.
(Comparative Example 1) to (Comparative Example 5)
The adhesives of Comparative Examples 1 to 5 were produced in the same manner as in Example 1 except that the materials and formulations used for adjusting the adhesive were adjusted to the values shown in Table 2.

Other compounds in Tables 1 and 2 are as follows.
TEGO Variplus AP: Ketonealdehyde condensation resin manufactured by Evonik Industries (B1-1): Trimethylolpropane adduct of toluene diisocyanate (NCO% = 17.7)
Isocyanate (B2-1): 4,4'-MDI (NCO% = 33.3)
Isocyanate (B2-2): Carbodiimide-modified MDI monomer (NCO% = 29.5%)
Isocyanate (B2-3): 50/50 (% by mass) mixture of 4,4'-MDI and 2,4'-MDI (NCO% = 33.3%)
Isocyanate (B3-1): Hexamethylene diisocyanate adduct-type polyisocyanate (NCO% = 9.5%)
Isocyanate (B3-2): Hexamethylene diisocyanate uretdione type polyisocyanate (NCO% = 21.8%)

<Manufacturing of packaging materials for batteries Fig. 2 configuration>
(Example 1)
The adhesive of Example 1 as the adhesive layer 2 was applied to the matte surface of the aluminum foil having a thickness of 40 μm as the metal layer 3 with a dry laminator in an amount of 4 g / square meter, and after the solvent was volatilized, the outer layer was applied. A stretched polyamide film having a thickness of 25 μm was laminated as the side base material layer 1.
Next, the adhesive for the adhesive layer 5 was applied to the glossy surface of the aluminum foil of the metal layer 3 of the obtained laminated film with a dry laminator at an amount of application amount: 4 g / square meter, and then the solvent was volatilized. An unstretched polypropylene film having a thickness of 40 μm was laminated as the sealant layer 4, and then cured (aged) at 60 ° C. for 5 days to cure the adhesive to obtain a laminated product.

(Example 2) to (Example 6)
In the same manner as in Example 1, the adhesives of Examples 2 to 6 were used as the adhesive layer 2 to obtain packaging materials for batteries of Examples 2 to 6.

(Comparative Example 1) to (Comparative Example 5)
In the same manner as in Example 1, the adhesives of Comparative Examples 1 to 5 were used as the adhesive layer 2 to obtain packaging materials for batteries of Comparative Examples 1 to 5.

The evaluation of the battery packaging material was performed as follows.
<Adhesive strength>
Using "Autograph AGS-J" manufactured by Shimadzu Corporation, the outer layer side base material of the battery packaging material of the Example or Comparative Example under the conditions of a peeling speed of 100 mm / min, a peeling width of 15 mm, and a peeling form of 180 ° peeling. The adhesive strength at the interface between the layer 1 and the metal layer 3 was evaluated. The higher the value, the more suitable as an adhesive.

<Moldability>
Using the "1ton desktop servo press (SBN-1000)" manufactured by Yamaoka Seisakusho Co., Ltd., the battery packaging material of the example or comparative example was cut into a size of 60 x 60 mm and used as a blank (molded material, material). did. With respect to the blank, the aluminum foil matte surface is on the convex side, and the molding height is changed from 4.5 mm to 6.5 mm with a straight mold with no molding height, and the aluminum foil is overhanged. The moldability was evaluated based on the maximum mold height at which breakage and floating between layers did not occur.

The punch shape of the mold used is a square with a side of 30 mm, a corner R2 mm, a punch shoulder R1 mm, and the die hole shape of the mold used is a square with a piece of 34 mm, a die hole corner R2 mm, and a die hole shoulder R: 1 mm. , The clearance between the punch and the die hole is 0.3 mm on one side. The clearance causes an inclination according to the molding height. The following three stages of evaluation were performed according to the height of molding.
〇: 5.0 mm or more (excellent in practical use)
Δ: 4.5 mm (practical range)
×: At 4.5 mm, breakage of aluminum foil and floating between each layer occur.

<Heat resistance>
Using the "1ton desktop servo press (SBN-1000)" manufactured by Yamaoka Seisakusho Co., Ltd., cut the battery packaging material of the example or comparative example into a size of 60 x 60 mm so that the aluminum foil mat surface is on the outside. Then, overhang molding was performed at a molding height of 5.0 mm using a straight mold having no molding height. A heat seal bar at 190 ° C. for 3 seconds was applied to the flange portion of the obtained 30 mm square tray so as to be in contact with the side wall portion, and the appearance in the vicinity of the boundary portion between the flange portion and the side wall portion was confirmed. It was evaluated whether there was any floating between the two.
○: No float (excellent in practical use)
Δ: Floating occurrence (practical range)
×: Floating occurs

<Moisture and heat resistance>
Using the "1ton desktop servo press (SBN-1000)" manufactured by Yamaoka Seisakusho Co., Ltd., cut the battery packaging material of the example or comparative example into a size of 60 x 60 mm so that the aluminum foil mat surface is on the outside. Then, overhang molding was performed at a molding height of 5.0 mm using a straight mold having no molding height. The obtained 30 mm square tray was placed in a constant temperature and humidity chamber at 85 ° C. and an 85% RH atmosphere, and allowed to stand for 48 hours. The tray was taken out from the constant temperature and humidity chamber, the appearance near the boundary between the flange portion and the side wall portion was confirmed, and it was evaluated whether or not floating occurred between the stretched polyamide film and the aluminum foil.
○: No float (excellent in practical use)
Δ: Floating occurrence (practical range)
×: Floating occurs

The results are shown in Tables 1 and 2. Of the NCO / OH ratios in Tables 2 and 3, the values corresponding to the above-mentioned [NCO] / [OH] are in the “Overall” column, and the values in the “B2” column are [NCO'] / [OH]. ] Is the value. The numerical value in parentheses in the "B2" column is the equivalent ratio of the isocyanate group derived from the isocyanate compound (B3) used in place of the isocyanate compound (B2) to the hydroxyl group.

From this result, by using the adhesive of the present invention, it has excellent moldability, and after heat fusion between the sealant layers performed for sealing the battery element, and for a long period of time under high temperature and high humidity. It is clear that even after the durability test, there is no decrease in the adhesive strength between the layers, and it is possible to obtain a packaging material for a battery in which appearance defects such as floating between layers are suppressed.

1: Outer layer side base material layer 2: Adhesive layer 3: Metal layer 4: Sealant layer 5: Adhesive layer

Claims (9)

Containing a polyol composition (A) and a polyisocyanate composition (B),
The polyol composition (A) contains a polyester polyol (A1) containing a polybasic acid or an alkyl esterified product thereof and a polyhydric alcohol as essential raw materials, and has an aromatic ring in the polybasic acid or an alkyl esterified product thereof. The ratio of the basic acid or the alkyl esterified product thereof is 96 mol% or more, and the polybasic acid having the aromatic ring or the alkyl esterified product thereof in the polybasic acid or the alkyl esterified product thereof is isophthalic acid, terephthalic acid, or an anhydride tri. Containing at least one selected from the group consisting of merit acids,
The polyisocyanate composition (B) is at least one selected from the group consisting of toluene diisocyanate, toluene diisocyanate oligomer, adduct, and nurate, and 2,2'-diphenylmethane diisocyanate, 2,4. Includes'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, and an isocyanate compound (B2) which is at least one selected from the group consisting of carbodiimide-modified diphenylmethane diisocyanate obtained by condensing at least one of these diphenylmethane diisocyanates in the presence of a catalyst.
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 [NCO] of isocyanate groups contained in the polyisocyanate composition (B) is 1.5 to 15
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 [NCO'] of isocyanate groups contained in the isocyanate compound (B2) is 0. . A two-component adhesive characterized by being 3 or more and 1.5 or less. 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 [NCO] of isocyanate groups contained in the polyisocyanate composition (B) is The two-component adhesive according to claim 1, which is 3 or more and 10 or less. 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 [NCO'] of isocyanate groups contained in the isocyanate compound (B2) is 0. The two-component adhesive according to any one of claims 1 or 2, which is 3 or more and 1.3 or less. The two-component adhesive according to any one of claims 1 to 3 , wherein the isocyanate compound (B1) is a trimethylolpropane adduct of toluene diisocyanate. The two-component adhesive according to any one of claims 1 to 4 , wherein the polyester polyol (A1) has a number average molecular weight of 2,000 to 100,000. A laminate obtained by laminating a plurality of base materials using the two-component adhesive according to any one of claims 1 to 5 . At least, the battery packaging material in which the outer layer side base material layer 1, the adhesive layer 2, the metal layer 3, and the sealant layer 4 are sequentially laminated, and the adhesive layer 2 is any one of claims 1 to 6 . A packaging material for a battery, which is a cured product of the above-mentioned two-component adhesive. A battery container obtained by molding the battery packaging material according to claim 7 . A battery using the battery container according to claim 8 .

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