Adhesives, laminates, battery packaging materials, and batteries

Abstract

To provide an adhesive that ensures superior adhesion between a nonpolar substrate such as olefin resin and a metal substrate, as well as superior heat resistance, even after aging at low temperatures, and a laminate and a battery packaging material each prepared by using the adhesive.SOLUTION: The present invention provides a two-part curable adhesive for lithium ion battery exterior material that contains a composition (X) containing a hydroxy group-modified polyolefin (A) and a composition (Y) containing a polyisocyanate compound (B), where the hydroxy group-modified polyolefin (A) is a crystalline C2-20 α-olefin polymer; and a laminate and a battery packaging material each prepared by using the adhesive.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an adhesive, more specifically, an adhesive suitable for bonding a resin base material and a metal base material, a laminate obtained by using the adhesive, an exterior material for a secondary battery, and a battery.

Background Art

[0002] A secondary battery typified by a lithium ion battery has a configuration in which a positive electrode, a negative electrode, and an electrolytic solution or the like are enclosed therebetween. Further, as an encapsulation bag for enclosing lead wires for taking out the electricity of the positive electrode and the negative electrode to the outside, a laminate in which a heat-sealing layer made of an olefin resin, a metal base material such as an aluminum foil or a metal vapor deposition layer, and a plastic are laminated is known to be used (Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] When bonding a heat-sealing layer made of an olefin resin and a metal base material via an adhesive, generally, an aging process for promoting the curing of the adhesive while heating is provided. The aging temperature and aging time in the aging process may be appropriately selected. For example, it is preferably carried out at 80°C or lower where the thermal shrinkage effect of the olefin resin is small. On the other hand, the lower the aging temperature and the shorter the aging time, the more difficult it is to exhibit the characteristics of the adhesive.

[0005] This invention has been made in view of the above circumstances, and aims to provide an adhesive that exhibits excellent adhesion between a non-polar substrate such as an olefin resin and a metal substrate, even when aged at low temperatures. Furthermore, it aims to provide a laminate obtained using such an adhesive, a secondary battery casing material obtained using said laminate, and a battery. [Means for solving the problem]

[0006] The present invention relates to a two-component curing adhesive for lithium-ion battery casing materials, comprising a composition (X) containing a hydroxyl-modified polyolefin (A) and a composition (Y) containing a polyisocyanate compound (B), wherein the hydroxyl-modified polyolefin (A) is crystalline and is a polymer of α-olefin having 2 to 20 carbon atoms. [Effects of the Invention]

[0007] The adhesive of the present invention exhibits excellent adhesion between non-polar substrates such as olefin resins and metal substrates, even when aged at low temperatures, and maintains its adhesive properties even when immersed in a solvent. Furthermore, the laminate of the present invention exhibits excellent adhesion and solvent resistance. [Modes for carrying out the invention]

[0008] <Adhesive> The two-component adhesive of the present invention comprises a composition (X) containing a hydroxyl-modified polyolefin (A) and a composition (Y) containing a polyisocyanate compound (B). The hydroxyl-modified polyolefin (A) is crystalline and is a polymer of α-olefin with 2 to 20 carbon atoms. The components of the adhesive of the present invention will be described in detail below.

[0009] (Composition (X)) (Hydroxy-modified polyolefin (A)) Composition (X) contains a hydroxyl-modified polyolefin (A). The hydroxyl-modified polyolefin (A) is a resin obtained by modifying a polymer of α-olefin having 2 to 20 carbon atoms with a hydroxyl-containing polymerizable monomer. This makes it possible to produce an adhesive with excellent adhesion, solvent resistance, electrolyte resistance, etc.

[0010] Examples of α-olefins having 2 to 20 carbon atoms include α-olefins having 2 or 3 carbon atoms such as ethylene and propylene, and α-olefins having 4 to 20 carbon atoms such as 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-eicosene. It is preferable to use at least one selected from ethylene, propylene, and 1-butene, and it is preferable to use at least one selected from propylene and 1-butene, and it is preferable to include propylene and 1-butene.

[0011] Polymers of α-olefins having 2 to 20 carbon atoms may be homopolymers or copolymers. The copolymers may be block copolymers or random copolymers. It is preferable that the polymers be copolymers of α-olefins having 2 to 20 carbon atoms.

[0012] Polymers of α-olefins having 2 to 20 carbon atoms may also be produced using polymerizable monomers other than α-olefins having 2 to 20 carbon atoms as raw materials. Examples of such polymerizable monomers include conjugated polyenes such as butadiene and isoprene, and unconjugated polyenes such as 1,4-hexadiene, 1,7-octadiene, dicyclopentadiene, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, 5-methylene-2-norbornene, and 2,5-norbornadiene.

[0013] Examples of hydroxyl group-containing polymerizable monomers include hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, glycerin mono(meth)acrylate, pentaerythritol mono(meth)acrylate, trimethylolpropane mono(meth)acrylate, tetramethylolethane mono(meth)acrylate, and butanediol mono(meth)acrylate. Examples include hydroxyl group-containing (meth)acrylic acid esters such as acrylate, polyethylene glycol mono(meth)acrylate, 2-(6-hydrohexanoyloxy)ethyl acrylate, and 2-(meth)acryloyloxyethyl acid phosphate; 10-undecen-1-ol, 1-octen-3-ol, 2-methanolorbornene, hydroxystyrene, N-methylolacrylamide, glycerin monoallyl ether, allyl alcohol, allyloxyethanol, 2-butene-1,4-diol, and glycerin monoalcohol.

[0014] For example, hydroxyl-modified polyolefin (A) may be obtained by polymerizing a composition containing an α-olefin having 2 to 20 carbon atoms and a hydroxyl-containing polymerizable monomer, or by first synthesizing a polymer of an α-olefin having 2 to 20 carbon atoms and then reacting it with a hydroxyl-containing polymerizable monomer. A method for reacting a polymer of an α-olefin having 2 to 20 carbon atoms with a hydroxyl-containing polymerizable monomer is, for example, (1) A method for reacting a polymer of α-olefin having 2 to 20 carbon atoms with a hydroxyl group-containing polymerizable monomer by dissolving the polymer in a solvent, adding a hydroxyl group-containing polymerizable monomer and a radical polymerization initiator, and then heating and stirring. (2) A method for reacting a polymer of α-olefin having 2 to 20 carbon atoms with a hydroxyl group-containing polymerizable monomer by heating and melting the molten product and adding a hydroxyl group-containing polymerizable monomer and a radical polymerization initiator, followed by stirring. (3) A method of mixing a polymer of α-olefin having 2 to 20 carbon atoms, a hydroxyl group-containing polymerizable monomer, and a radical polymerization initiator, and supplying the resulting mixture to an extruder and reacting the polymer of α-olefin having 2 to 20 carbon atoms with the hydroxyl group-containing polymerizable monomer while heating and kneading. (4) A method for reacting a polymer of α-olefin having 2 to 20 carbon atoms with a hydroxyl group-containing polymerizable monomer by immersing it in a solution in which a hydroxyl group-containing polymerizable monomer and a radical polymerization initiator are dissolved in an organic solvent, and then heating the solution to a temperature at which the polymer of α-olefin having 2 to 20 carbon atoms does not dissolve. These are some examples.

[0015] The reaction temperature in (1) to (4) above is, for example, 50°C to 300°C, more preferably 80°C to 300°C. The reaction temperature in (1) to (4) above is, for example, 1 minute to 10 hours. The reaction method can be batch or continuous, and the batch method is preferred in order to carry out the denaturation reaction uniformly.

[0016] Examples of radical polymerization initiators include organic peroxides such as dicumyl peroxide, benzoyl peroxide, dichlorobenzoyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di(peroxybenzoate)hexyn-3, 1,4-bis(tert-butylperoxyisopropyl)benzene, lauroyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexyn-3, and 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane. Organic peresters such as tert-butyl peracetate, tert-butyl perphenyl acetate, tert-butyl perisobutyrate, tert-butyl persec-octoate, tert-butyl perpivalate, cumyl perpivalate, tert-butyl perdiethyl acetate, and tert-butyl peroxybenzoate. Examples of the azo compounds include azobisisobutyronitrile, dimethylazobisisobutyronitrile and the like, and other initiators may also be used. The blending ratio of the radical polymerization initiator is, for example, 0.001 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymer of an olefin having 2 to 20 carbon atoms.

[0017] In order to obtain good adhesiveness, the weight average molecular weight of the hydroxyl group-modified polyolefin (A) used in the present invention is preferably 10,000 or more. Further, in order to ensure appropriate fluidity, the weight average molecular weight of the hydroxyl group-modified polyolefin (A) is preferably 500,000 or less. In the present invention, two or more kinds of hydroxyl group-modified polyolefins (A) having different weight average molecular weights can also be used in combination. At this time, it is preferable that the weight average molecular weight of all the hydroxyl group-modified polyolefins (A) is 10,000 or more and 500,000 or less, but a hydroxyl group-modified polyolefin (A) having a weight average molecular weight of less than 10,000 or exceeding 500,000 may be included. Among the hydroxyl group-modified polyolefins (A) used in the adhesive of the present invention, those having a weight average molecular weight of 10,000 or more and 500,000 or less are preferably 50% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more.

[0018] 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.

[0019] 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-8020 model II manufactured by Tosoh Corporation Measurement conditions: Column temperature 40 °C Solvent: Tetrahydrofuran Flow rate: 0.35 ml / min Standard; monodisperse polystyrene Sample: 100 μl of a tetrahydrofuran solution containing 0.2% by mass (based on resin solids content) filtered through a microfilter.

[0020] The hydroxyl-modified polyolefin (A) used in the present invention is crystalline. In this specification, the presence or absence of crystallinity is determined by the presence or absence of a melting point (peak) measured by the method described below. The melting point of the hydroxyl-modified polyolefin (A) is preferably 40°C or higher, more preferably 50°C or higher, and even more preferably 60°C or higher. Furthermore, the melting point of the hydroxyl-modified polyolefin (A) is preferably 100°C or lower, more preferably 95°C or lower, and even more preferably 90°C or lower.

[0021] The melting point of hydroxyl-modified polyolefin (A) is measured by DSC (Differential Scanning Calorimetry). Specifically, the temperature is increased at 10°C / min from the cooling temperature to the heating temperature, then cooled to the cooling temperature at 10°C / min to remove the thermal history, and then heated again at 10°C / min to the heating temperature. The peak temperature during the second heating is taken as the melting point. The cooling temperature is set to be at least 50°C lower than the crystallization temperature, and the heating temperature is set to be at least 30°C higher than the melting point temperature. The cooling and heating temperatures are determined by trial measurements.

[0022] It is also possible to use two or more types of hydroxyl-modified polyolefins (A) with different melting points in combination. In this case, it is preferable that all hydroxyl-modified polyolefins (A) have a melting point of 40°C or higher and 100°C or lower, but it is also possible that some hydroxyl-modified polyolefins (A) have a melting point of less than 40°C or more than 100°C. Of the hydroxyl-modified polyolefins (A) used in the adhesive of the present invention, it is preferable that 50% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more, be present in the adhesive.

[0023] The hydroxyl-modified polyolefin (A) preferably has a heat of fusion of 0 J / g or more and 50 J / g or less. This allows for the creation of an adhesive with excellent adhesive strength, solvent resistance, and electrolyte resistance. The heat of fusion of the hydroxyl-modified polyolefin (A) can be measured by the method described in JIS-K-7122.

[0024] It is preferable to use a hydroxyl-modified polyolefin (A) having a crystallization heat of 1 J / g or more, more preferably 10 J / g or more, and 100 J / g or less, more preferably 60 J / g or less. This makes it possible to provide a laminate that has excellent solvent resistance, electrolyte resistance, and maintains adhesive strength even when used in applications that contain heat-generating contents or in environments where the ambient temperature tends to rise. The crystallization heat can be measured by the method described in JIS-K-7122.

[0025] The hydroxyl-modified polyolefin (A) preferably has a solids hydroxyl value of 0.1 mg KOH / g or more and 30 mg KOH / g or less. This makes it possible to produce an adhesive with excellent adhesion, solvent resistance, electrolyte resistance, etc. The hydroxyl value of the hydroxyl-modified polyolefin (A) can be calculated, for example, from the weight-average molecular weight of the hydroxyl-modified polyolefin (A) and the amount of polymerizable monomer containing hydroxyl groups added.

[0026] (Acid-modified polyolefin (C)) Composition (X) may contain an acid-modified polyolefin (C) in addition to a hydroxyl-modified polyolefin (A). The acid-modified polyolefin (C) is a resin obtained by modifying a polymer of α-olefin having 2 to 20 carbon atoms with an acid-containing polymerizable monomer. As a raw material for α-olefin hydroxyl-modified polyolefin (A) having 2 to 20 carbon atoms, materials similar to those exemplified can be used. It is preferable to use at least one selected from propylene and 1-butene, and it is preferable to include propylene and 1-butene.

[0027] The polymer of α-olefins having 2 to 20 carbon atoms may be a homopolymer or a copolymer. The copolymer may be a block copolymer or a random copolymer. It is preferable that the polymer is a copolymer of α-olefins having 2 to 20 carbon atoms. Polymers of α-olefins having 2 to 20 carbon atoms may also be produced using polymerizable monomers other than α-olefins having 2 to 20 carbon atoms as raw materials. The same materials exemplified for hydroxyl-modified polyolefin (A) can be used.

[0028] Examples of polymerizable monomers containing acid groups include acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid, mesaconic acid, maleic anhydride, 4-methylcyclohexe-4-ene-1,2-dicarboxylic acid anhydride, bicyclo[2.2.2]octo-5-ene-2,3-dicarboxylic acid anhydride, 1,2,3,4,5,8,9,10-octahydronaphthalene-2,3-dicarboxylic acid anhydride, and 2-octa- Examples include 1,3-diketospiro[4.4]non-7-ene, bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid anhydride, maleopimaric acid, tetrahydrophthalic acid anhydride, methyl-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid anhydride, methyl-norbornene-5-ene-2,3-dicarboxylic acid anhydride, norbornne-5-ene-2,3-dicarboxylic acid anhydride, etc.

[0029] The method for synthesizing acid-modified polyolefin (C) is not particularly limited and can be synthesized by conventionally known methods. For example, it can be synthesized by the same method as illustrated for hydroxyl-modified polyolefin (A).

[0030] The weight-average molecular weight of the acid-modified polyolefin (C) is preferably 10,000 or more. Furthermore, in order to ensure adequate fluidity, the weight-average molecular weight of the acid-containing polyolefin (C) is preferably 500,000 or less.

[0031] The acid-modified polyolefin (C) is preferably crystalline. The melting point of the acid-modified polyolefin (C) is preferably 40°C or higher, more preferably 50°C or higher, and even more preferably 60°C or higher. Furthermore, the melting point of the acid-modified polyolefin (C) is preferably 100°C or lower, more preferably 95°C or lower, and even more preferably 90°C or lower.

[0032] The acid-modified polyolefin (C) preferably has a heat of fusion of 0 J / g or more and 50 J / g or less. Furthermore, the acid-modified polyolefin (C) preferably has a heat of crystallization of 1 J / g or more, more preferably 10 J / g or more, and 100 J / g or less, more preferably 60 J / g or less.

[0033] The acid value of the acid-modified polyolefin (C) is preferably 0.1 mg KOH / g or higher, as this provides good adhesion to metal substrates. On the other hand, depending on the structure of the olefin chain, a high acid value tends to make it difficult for the olefin chain to crystallize in the cured coating due to the large number of crosslinking points. Therefore, from the viewpoint of solvent resistance and electrolyte resistance, it is preferable to have an acid value of 50 mg KOH / g or less. More preferably, it is 5 mg KOH / g to 40 mg KOH / g, and 5 mg KOH / g to 30 mg KOH / g.

[0034] The acid value of acid-modified polyolefins (C) is determined, for example, using FT-IR (Japan Spectroscopic Co., Ltd., FT-IR4200) and the coefficient (f) obtained from a calibration curve prepared with a chloroform solution of maleic anhydride, and the stretching peak of the anhydride ring of maleic anhydride in the maleic anhydride-modified polyolefin solution (1780 cm²). -1 Absorbance (I) of ) and the stretching peak of the carbonyl group of maleic acid (1720 cm²) -1 It can be calculated using the absorbance (II) of ) by the following formula. In the following formula, the molecular weight of maleic anhydride is 98.06 and the molecular weight of potassium hydroxide is 56.11.

[0035]

number

[0036] If composition (X) contains acid-modified polyolefin (C), the amount can be adjusted as appropriate. The content of acid-modified polyolefin (C) in relation to the total solid content of hydroxyl-modified polyolefin (A) and acid-modified polyolefin (C) is, for example, 90% by mass or less, in another embodiment 15% by mass or less, in yet another 10% by mass or less, and in yet another 5% by mass or less. This makes it possible to produce an adhesive with excellent adhesion and storage stability.

[0037] (Polyolefin (D)) Composition (X) may also contain a polyolefin (D) that does not have reactive functional groups in addition to the hydroxyl-modified polyolefin (A). Preferably, the polyolefin (D) is a crystalline olefin resin. When the polyolefin (D) is a crystalline olefin resin, the polarity of the cured adhesive film is reduced, and its resistance to the electrolyte is improved.

[0038] Polyolefins (D) include homopolymers and copolymers of olefins having 2 to 8 carbon atoms, such as ethylene, propylene, isobutylene, 1-butene, 4-methyl-1-pentene, hexene, and vinylcyclohexane, as well as copolymers of olefins having 2 to 8 carbon atoms with other monomers. Specifically, examples include polyethylene such as high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene resin, polypropylene, polyisobutylene, poly(1-butene), poly(4-methyl-1-pentene), polyvinylcyclohexane, α-olefin copolymers such as ethylene-propylene block copolymer, ethylene-propylene random copolymer, ethylene-1-butene copolymer, ethylene-4-methyl-1-pentene copolymer, and ethylene-hexene copolymer, as well as ethylene-methyl methacrylate copolymer and propylene-1-butene copolymer. Among these, homopolymers of olefins having 3 to 8 carbon atoms and copolymers of two or more olefins having 3 to 8 carbon atoms are preferred, with propylene homopolymers or copolymers being more preferred, and propylene homopolymers being even more preferred, as they offer particularly good adhesive strength.

[0039] Polyolefin (D) has high solubility in solvents and improved coating properties, so a weight-average molecular weight of 2,000 to 300,000 is preferred. More preferably, the weight-average molecular weight of polyolefin (D) is 20,000 to 250,000, and even more preferably 40,000 to 250,000.

[0040] It is also possible to use two or more types of polyolefins (D) with different weight-average molecular weights in combination. In this case, it is preferable that all polyolefins (D) have a weight-average molecular weight of 2,000 or more and 300,000 or less, but it is also possible that polyolefins (D) with a weight-average molecular weight of less than 2,000 or more and 300,000 or more are included. When using polyolefins (D), it is preferable that 50% or more by mass of polyolefins (D) have a weight-average molecular weight of 2,000 or more and 300,000 or less, more preferably 80% or more by mass, and even more preferably 90% or more by mass.

[0041] The melting point of polyolefin (D) is preferably 50°C to 100°C. A melting point of 50°C or higher can more reliably improve electrolytic resistance, while a melting point of 100°C or lower can maintain good coating properties. The melting point of polyolefin (D) is more preferably 50 to 95°C, and more preferably 60 to 90°C.

[0042] Furthermore, two or more types of polyolefins (D) with different melting points can be used in combination. In this case, it is preferable that all polyolefins (D) have a melting point of 50°C or higher and 100°C or lower, but polyolefins (D) with a melting point below 50°C or above 100°C may be included. It is preferable that 50% by mass or more of the polyolefins (D) have a melting point of 50°C or higher and 100°C or lower, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

[0043] If composition (X) contains polyolefin (D), its amount can be adjusted as appropriate. The mass ratio (A):(D) of hydroxyl-modified polyolefin (A) to polyolefin (D) is, for example, 100:0 to 10:90, in another embodiment it is 100:1 to 15:85, and in yet another embodiment it is 75:25 to 15:85. This makes it possible to produce an adhesive with excellent solvent resistance, electrolyte resistance, and storage stability.

[0044] (Composition (Y)) (Polyisocyanate compound (B)) Composition (Y) comprises a polyisocyanate compound (B). The polyisocyanate compound (B) can be any conventionally known compound, such as aromatic diisocyanates including 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, and 1,5-naphthalene diisocyanate; aromatic aliphatic diisocyanates such as xylylene diisocyanate; isophorone diisocyanate; and hydrogenated diphenylmethane diisocyanate. Examples include diisocyanates such as isocyanates, alicyclic diisocyanates such as hydrogenated xylylene diisocyanate, and aliphatic diisocyanates such as pentamethylene diisocyanate and hexamethylene diisocyanate, as well as compounds derived therefrom, namely isocyanurate, adduct, biuret, uretdione, and allophanate forms of the diisocyanates, prepolymers having isocyanate residues (low polymers obtained from diisocyanates and polyols), or complexes thereof.

[0045] As the polyisocyanate compound (B), a compound obtained by reacting some of the isocyanate groups of the polyfunctional isocyanate compound described above with a compound that is reactive with isocyanate groups may be used. Compounds that react with isocyanate groups include: compounds containing amino groups such as butylamine, hexylamine, octylamine, 2-ethylhexylamine, dibutylamine, ethylenediamine, benzylamine, and aniline; compounds containing hydroxyl groups such as methanol, ethanol, propanol, isopropanol, butanol, hexanol, octanol, 2-ethylhexyl alcohol, dodecyl alcohol, ethylene glycol, propylene glycol, benzyl alcohol, and phenol; compounds containing epoxy groups such as allyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol glycidyl ether, and cyclohexanedimethanol diglycidyl ether; and compounds containing carboxylic acids such as acetic acid, butanoic acid, hexanoic acid, octanoic acid, succinic acid, adipic acid, sebacic acid, and phthalic acid.

[0046] The polyisocyanate compound (B) preferably contains at least one selected from aliphatic polyisocyanates and alicyclic polyisocyanates. The content of aliphatic polyisocyanates and / or alicyclic polyisocyanates in the polyisocyanate compound (B) is preferably 50% by mass or more, more preferably 80% by mass or more, and even more preferably 95% by mass or more. The entire amount of the polyisocyanate compound (B) may be aliphatic polyisocyanates and / or alicyclic polyisocyanates.

[0047] The polyisocyanate compound (B) may be a mixture of at least one derivative of an aliphatic diisocyanate and / or an alicyclic diisocyanate (isocyanurate, adduct, biuret type, uretdione, allophanate, or prepolymer having isocyanate residues) and an aliphatic diisocyanate and / or an alicyclic diisocyanate. In this case, the content of the aliphatic diisocyanate and / or alicyclic diisocyanate is 0.0.1% by mass or more and 1% by mass or less.

[0048] It is preferable that composition (X) and composition (Y) are used in such a way that the ratio of the number of moles of isocyanate groups [NCO] in composition (Y) to the number of moles of hydroxyl groups [OH] in composition (X), [NCO] / [OH], is in the range of 0.5 to 5.0.

[0049] (Additive (E)) The adhesive of the present invention may contain additive (E). Various additives such as silane coupling agents (E-1), urethane catalysts (E-2), tackifiers (E-3), thermoplastic elastomers (E-4), epoxy resins (E-5), monomers having functional groups reactive with isocyanates (E-6), acid anhydrides, plasticizers, phosphoric acid compounds, and reactive elastomers can be used as additive (E). The content of these additives (E) can be appropriately adjusted within a range that does not impair the function of the adhesive of the present invention.

[0050] Examples of silane coupling agents (E-1) 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 vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, vinyltrimethoxysilane, and γ-methacryloxypropyltrimethoxysilane; and hexamethyldisilazane and γ-mercaptopropyltrimethoxysilane.

[0051] As the urethane catalyst (E-2), catalysts such as metal catalysts, amine catalysts, aliphatic cyclic amide compounds, titanium chelate complexes, and organophosphorus compounds can be used.

[0052] Examples of metal catalysts include metal complex catalysts, inorganic metal catalysts, and organometallic catalysts. Specifically, metal complex catalysts are acetylacetonate salts of metals selected from the group consisting of Fe (iron), Mn (manganese), Cu (copper), Zr (zirconium), Th (thorium), Ti (titanium), Al (aluminum), and Co (cobalt). Examples include iron acetylacetonate, manganese acetylacetonate, copper acetylacetonate, and zirconia acetylacetonate. Of these, iron acetylacetonate (Fe(acac)3) or manganese acetylacetonate (Mn(acac)2) are preferred in terms of toxicity and catalytic activity.

[0053] Examples of inorganic metal catalysts include catalysts selected from Fe, Mn, Cu, Zr, Th, Ti, Al, and Co.

[0054] Examples of organometallic catalysts include stanus diacetate, stanus dioctoate, stanus dioleate, stanus dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dichloride, dioctyltin dilaurate, nickel octoate, nickel naphthenate, cobalt octoate, cobalt naphthenate, bismuth octoate, and bismuth naphthenate. Of these, organotin catalysts are preferred, and stanus dioctoate and dibutyltin dilaurate are more preferred.

[0055] Examples of amine catalysts include triethylenediamine, 2-methyltriethylenediamine, quinuclidine, 2-methylquinuclidine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethylpropylenediamine, N,N,N',N”,N”-pentamethyldiethylenetriamine, N,N,N',N”,N”-pentamethyl-(3-aminopropyl)ethylenediamine, N,N,N',N”,N”-pentamethyldipropylenetriamine, N,N,N',N'-tetramethyl Hexamethylenediamine, bis(2-dimethylaminoethyl) ether, dimethylethanolamine, dimethylisopropanolamine, dimethylaminoethoxyethanol, N,N-dimethyl-N'-(2-hydroxyethyl)ethylenediamine, N,N-dimethyl-N'-(2-hydroxyethyl)propanediamine, bis(dimethylaminopropyl)amine, bis(dimethylaminopropyl)isopropanolamine, 3-quinuclidinol, N,N,N',N'-tetramethylguanidine , 1,3,5-Tris(N,N-dimethylaminopropyl)hexahydro-S-triazine, 1,8-Diazabicyclo[5.4.0]undecene-7, 1,5-Diazabicyclo[4.3.0]nonene-5, N-Methyl-N'-(2-dimethylaminoethyl)piperazine, N,N'-dimethylpiperazine, Dimethylcyclohexylamine, N-Methylmorpholine, N-Ethylmorpholine, 1-Methylimidazole, 1,2-Dimethylimidazole, 1-Isobutyl-2-Methylimidazole, 1-Dimethyl Examples include tertiary amines such as tylaminopropylimidazole, N,N-dimethylhexanolamine, N-methyl-N'-(2-hydroxyethyl)piperazine, 1-(2-hydroxyethyl)imidazole, 1-(2-hydroxypropyl)imidazole, 1-(2-hydroxyethyl)-2-methylimidazole, and 1-(2-hydroxypropyl)-2-methylimidazole, as well as compounds obtained by amine salting these tertiary amines with phenol, octyl acid, quaternized tetraphenyl borate salt, etc.

[0056] Examples of aliphatic cyclic amide compounds include δ-valerolactam, ε-caprolactam, ω-enanthollactam, η-capryllactam, and β-propiolactam. Among these, ε-caprolactam is preferred due to its excellent curing-accelerating effect.

[0057] Titanium chelate complexes are compounds whose catalytic activity can be enhanced by ultraviolet irradiation, and titanium chelate complexes with aliphatic or aromatic diketones as ligands are preferred because they exhibit excellent curing acceleration effects. Furthermore, in this invention, in addition to aromatic or aliphatic diketones as ligands, those containing alcohols with 2 to 10 carbon atoms are preferred because the effects of the present invention are more pronounced.

[0058] Furthermore, if composition (X) contains an acid-modified polyolefin (C), it is also preferable to use organophosphorus compounds such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, tris(4-methylphenyl)phosphine, tris(4-butylphenyl)phosphine, diphenylphosphine, and phenylphosphine in addition to the urethane catalyst (E-2).

[0059] Examples of tackifiers (E-3) include rosin-based or rosin ester-based tackifiers, terpene-based or terpene phenol-based tackifiers, saturated hydrocarbon resins, coumarone-based tackifiers, coumarone-indene-based tackifiers, styrene resin-based tackifiers, xylene resin-based tackifiers, phenol resin-based tackifiers, and petroleum resin-based tackifiers. These may be used individually or in combination of two or more types.

[0060] Suitable thermoplastic elastomers (E-4) include, for example, styrene-butadiene-styrene copolymer, styrene-ethylene-butylene-styrene copolymer, styrene-ethylene-propylene-styrene copolymer, styrene-ethylene-propylene copolymer, styrene-isoprene-styrene copolymer, styrene-ethylene-(ethylene-propylene)-styrene copolymer, styrene-isobutylene-styrene copolymer, and modified versions thereof, hydrogenated versions, graft copolymers having styrene structures in the side chains, core-shell type multilayer rubbers having styrene structures in the shell, etc., and blends of two or more types are also acceptable. Among these, styrene-ethylene-butylene-styrene copolymer, styrene-ethylene-propylene-styrene copolymer, and styrene-ethylene-(ethylene-propylene)-styrene copolymer are particularly noteworthy.

[0061] Thermoplastic elastomers (E-4) may also have reactive functional groups. Examples of such functional groups include hydroxyl groups, carboxyl groups, carbonyl groups, thiocarbonyl groups, acid halide groups, acid anhydride groups, thiocarboxylic acid groups, aldehyde groups, thioaldehyde groups, carboxylic acid ester groups, amide groups, sulfonic acid groups, sulfonic acid ester groups, phosphoric acid groups, phosphoric acid ester groups, amino groups, imino groups, nitrile groups, pyridyl groups, quinoline groups, epoxy groups, thioepoxy groups, sulfide groups, isocyanate groups, isothiocyanate groups, silicon halide groups, alkoxysilicon groups, tin halide groups, boronic acid groups, boron-containing groups, boronic acid bases, alkoxytin groups, and phenyltin groups.

[0062] Examples of epoxy resins (E-5) include bisphenol-type epoxy resins such as bisphenol A-type epoxy resin and bisphenol F-type epoxy resin; biphenyl-type epoxy resins such as biphenyl-type epoxy resin and tetramethylbiphenyl-type epoxy resin; and dicyclopentadiene-phenol addition reaction type epoxy resins. It is preferable to use epoxy resin (E-5) with a number-average molecular weight (Mn) of 300 to 2,000. It is also preferable to use epoxy resin with an epoxy equivalent weight of 150 to 1,000 g / equivalent.

[0063] Examples of monomers (E-6) having a functional group reactive with isocyanates include hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, glycerin mono(meth)acrylate, pentaerythritol mono(meth)acrylate, trimethylolpropane mono(meth)acrylate, tetramethylolethane mono(meth)acrylate, butanediol mono(meth)acrylate, polyethylene glycol mono(meth)acrylate, 2-(6-hydrohexanoyloxy)ethyl acrylate, 2-(meth)acryloyloxyethyl acid phosphate, and other hydroxyl group-containing (meth)acrylic acid esters; 10-undecen-1-ol, 1-octen-3-ol, 2-methanolorbornene, hydroxystyrene, N-methylol Crylamide, glycerin monoallyl ether, allyl alcohol, allyloxyethanol, 2-butene-1,4-diol, hydroxyl monomers such as glycerin monoalcohol, acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid, mesaconic acid, maleic anhydride, 4-methylcyclohexe-4-ene-1,2-dicarboxylic acid anhydride, bicyclo[2.2.2]octo-5-ene-2,3-dicarboxylic acid anhydride, 1,2,3,4,5,8,9,10-octahydr Examples include monomers having acidic groups such as ronaphthalene-2,3-dicarboxylic anhydride, 2-octa-1,3-diketospiro[4.4]non-7-ene, bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic anhydride, maleopimaric acid, tetrahydrophthalic anhydride, methyl-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic anhydride, methyl-norbornene-5-ene-2,3-dicarboxylic anhydride, and norborn-5-ene-2,3-dicarboxylic anhydride. The content of monomers (E-6) having functional groups that react with isocyanates is, for example, 5% by mass or less of the solid content of composition (X).

[0064] Examples of acid anhydrides include cyclic aliphatic acid anhydrides, aromatic acid anhydrides, and unsaturated carboxylic acid anhydrides, and one or more can be used in combination. More specifically, for example, phthalic anhydrides, trimellitic anhydrides, pyromellitic anhydrides, benzophenonetetracarboxylic anhydrides, dodecenyl succinic anhydrides, polyadipic anhydrides, polyazelaic anhydrides, polysebacic anhydrides, poly(ethyloctadecanediic acid) anhydrides, poly(phenylhexadecanedioic acid) anhydrides, tetrahydrophthalic anhydrides, methyltetrahydrophthalic anhydrides, methylhexahydrophthalic anhydrides, hexahydrophthalic anhydrides, methylhymic anhydrides, trialkyltetrahydrophthalic anhydrides, Examples include methylcyclohexenedicarboxylic acid anhydride, methylcyclohexenetetracarboxylic acid anhydride, ethylene glycol bistrimellitate dianhydride, hetic acid anhydride, nadic acid anhydride, methylnadic acid anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexane-1,2-dicarboxylic acid anhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid dianhydride, and 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid dianhydride.

[0065] Furthermore, the above-mentioned compounds modified with glycol may be used as acid anhydrides. Examples of glycols that can be used for modification include alkylene glycols such as ethylene glycol, propylene glycol, and neopentyl glycol; and polyether glycols such as polyethylene glycol, polypropylene glycol, and butyltetramethylene ether glycol. Moreover, copolymer polyether glycols of two or more of these glycols and / or polyether glycols may also be used.

[0066] The amount of acid anhydride added is preferably 0.01 parts by mass or more, and more preferably 0.8 parts by mass or more, per 100 parts by mass of resin (A). Furthermore, the amount of acid anhydride added is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and more preferably 1.5 parts by mass or less, per 100 parts by mass of resin (A). This improves the adhesion between the adhesive and the metal, resulting in an adhesive with excellent initial adhesive strength and adhesive strength after heat sealing.

[0067] The reason why using acid anhydrides in adhesives improves their adhesion and heat resistance is not entirely clear, but it is speculated that: Acid anhydrides possess polar groups and have excellent affinity for metal substrates. In addition, because their molecular weight is relatively small, they are relatively easy to move. It is thought that they move to the metal substrate side before the coated adhesive completely hardens, acting as a so-called anchoring agent and contributing to improved adhesion and heat resistance.

[0068] Examples of plasticizers include polyisoprene, polybutene, and Procell oil. Examples of thermoplastic elastomers include styrene-butadiene copolymer (SBS), hydrogenated styrene-butadiene copolymer (SEBS), SBBS, hydrogenated styrene-isoprene copolymer (SEPS), styrene block copolymer (TPS), and olefin-based elastomer (TPO). Examples of reactive elastomers include those obtained by acid modification of these elastomers.

[0069] Examples of phosphate compounds include phosphates such as hypophosphorous acid, phosphate, orthophosphate, and subphosphoric acid; condensed phosphates such as metaphosphate, pyrophosphate, tripolyphosphate, polyphosphate, and ultraphosphate; and monomethyl orthophosphate, monoethyl orthophosphate, monopropyl orthophosphate, monobutyl orthophosphate, mono-2-ethylhexyl orthophosphate, monophenyl orthophosphate, monomethyl phosphate, monoethyl phosphate, monopropyl phosphate, monobutyl phosphate, mono-2-ethylhexyl phosphate, monophenyl phosphate. Examples include mono- and diesterified compounds of di-2-ethylhexyl orthophosphate, dimethyl diphenyl orthophosphate, diethyl phosphate, dipropyl phosphate, dibutyl phosphate, di-2-ethylhexyl phosphate, and diphenyl phosphate; mono- and diesterified compounds of condensed phosphoric acid and alcohols; for example, those obtained by adding epoxy compounds such as ethylene oxide and propylene oxide to the aforementioned phosphoric acids; and epoxy phosphate esters obtained by adding the aforementioned phosphoric acids to aliphatic or aromatic diglycidyl ethers.

[0070] (Organic solvents) The adhesive of the present invention can achieve proper coating properties by further incorporating an organic solvent in addition to the above-mentioned components, thereby ensuring fluidity. Such organic solvents are not particularly limited as long as they can be removed by volatilization through overheating during the drying process when the adhesive is applied. Examples include aromatic organic solvents such as toluene and xylene; aliphatic organic solvents such as n-hexane and n-heptane; alicyclic organic solvents such as cyclohexane and methylcyclohexane; halogenated organic solvents such as trichloroethylene, dichloroethylene, chlorobenzene, and chloroform; ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ester solvents such as ethyl acetate and butyl acetate; ether solvents such as diisopropyl ether, butyl cellosolve, tetrahydrofuran, dioxane, and butyl carbitol; glycol ether solvents such as diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, and propylene glycol monomethyl ether; and glycol ester solvents such as ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, and diethylene glycol monoethyl ether acetate. These may be used individually or in combination of two or more.

[0071] To obtain an adhesive with excellent solubility and coating properties for hydroxyl-modified polyolefin (A), it is preferable to use a mixed solvent consisting of at least one selected from alicyclic organic solvents and aromatic organic solvents, and at least one selected from ester solvents and ketone solvents. The amounts of these solvents are appropriately adjusted according to the desired balance between the solubility of hydroxyl-modified polyolefin (A) and coating properties. Methylcyclohexane is preferred as the alicyclic organic solvent, and toluene is preferred as the aromatic organic solvent. Ethyl acetate is preferred as the ester solvent, and methyl ethyl ketone is preferred as the ketone solvent.

[0072] The amount of organic solvent used is preferably such that the solid content of composition (X) is 5 to 30% by mass. Furthermore, it is preferable that the solid content of composition (Y) is 10 to 100% by mass. This results in an adhesive with excellent coating properties and wettability to metal films.

[0073] The adhesive of the present invention exhibits excellent adhesion and heat resistance between a non-polar substrate such as an olefin resin and a metal substrate.

[0074] <Laminate> The laminate of the present invention includes a first substrate, a second substrate, and an adhesive layer disposed between the first and second substrates to bond the first and second substrates together. The adhesive layer is a cured coating of the adhesive described above. In addition to the first and second substrates, other substrates may also be included. The adhesive layer bonding the first substrate to the other substrates, and the second substrate to the other substrates, may or may not be a cured coating of the adhesive of the present invention.

[0075] Examples of the first substrate, second substrate, and other substrates include paper, olefin resins, acrylonitrile-butadiene-styrene copolymers (ABS resins), polyvinyl chloride resins, fluororesins, poly(meth)acrylic resins, carbonate resins, polyamide resins, polyimide resins, polyphenylene ether resins, polyphenylene sulfide resins, synthetic resin films obtained from polyester resins, copper foil, aluminum foil, and the like.

[0076] The adhesive of the present invention exhibits excellent adhesion between a non-polar substrate, such as an olefin resin, and a metal substrate. Therefore, it is preferable that one of the first and second substrates is a non-polar substrate and the other is a metal substrate, but the invention is not limited thereto.

[0077] The laminate of the present invention is obtained by applying the adhesive of the present invention to one of the first substrate and the second substrate, then laminating the other substrate, and curing the adhesive. It is preferable to include a drying step between the application of the adhesive and the lamination of the first substrate and the second substrate. Adhesive application methods include gravure coater, microgravure coater, reverse coater, bar coater, roll coater, and die coater. The amount of adhesive applied should be 0.5 to 20.0 g / m² after drying. 2 It is preferable to adjust it to the following: 0.5g / m 2 If the value falls below 20.0 g / m², the ability to apply the coating continuously and uniformly tends to decrease. 2 If the value exceeds a certain level, the solvent release properties after application will also decrease, making it easier for problems such as reduced workability and residual solvent to occur.

[0078] The temperature of the laminating roll when laminating the first substrate and the second substrate is 25-120°C, and the pressure is 3-300 kg / cm². 2 It is preferable that this be the case. It is preferable to perform an aging process after bonding the first substrate and the second substrate together. The aging conditions are preferably 25 to 100°C for 12 to 240 hours.

[0079] In particular, the adhesive of the present invention exhibits good initial adhesive strength and solvent resistance even when aged at relatively low temperatures, such as 60°C or below, and even 55°C or below. When aging is performed at 60°C or below, the aging time is preferably 72 hours or more. There is no particular upper limit to the aging time, but sufficient effects are achieved at around 168 hours. From the viewpoint of balancing aging temperature and aging time, it is preferable to perform the aging process at 40 to 60°C for 24 to 168 hours.

[0080] <Battery packaging material> The battery packaging material of the present invention includes, as an example, a first substrate, a second substrate, a third substrate, a first adhesive layer for bonding the first substrate and the second substrate, and a second adhesive layer for bonding the second substrate and the third substrate. The first substrate is a polyolefin film, and the second substrate is a metal foil. The third substrate is a resin film such as nylon or polyester. The first adhesive layer is a cured coating film of the adhesive of the present invention. The second adhesive layer may or may not be a cured coating film of the adhesive of the present invention. On the side of the third substrate opposite to where the second adhesive layer is provided, another substrate may be provided, either via an adhesive layer or without an adhesive layer, or a coating layer may be provided. Other substrates and coating layers are not required.

[0081] The polyolefin film can be appropriately selected from conventionally known olefin resins. For example, although not particularly limited, polyethylene, polypropylene, ethylene propylene copolymers, etc., can be used. It is preferable that the film be unstretched. The film thickness of the polyolefin film is not particularly limited, but is preferably 10 μm or more, more preferably 20 μm or more, and even more preferably 25 μm or more. It is also preferably 100 μm or less, more preferably 95 μm or less, and even more preferably 90 μm or less. The first substrate functions as a sealant layer when heat-sealing and bonding together the battery packaging materials of the present invention during the manufacturing of the battery described later.

[0082] Examples of metal foils include aluminum, copper, and nickel. These metal foils may be subjected to surface treatments such as sandblasting, polishing, degreasing, etching, surface treatment by immersion or spraying with rust inhibitors, trivalent chromium conversion treatment, phosphate chlorination treatment, sulfide conversion treatment, anodic oxidation film formation, and fluororesin coating. Among these, those treated with trivalent chromium conversion treatment are preferred due to their superior adhesion retention performance (resistance to environmental degradation) and corrosion resistance. Furthermore, the thickness of this metal film is preferably in the range of 10 to 100 μm from the viewpoint of corrosion prevention.

[0083] Examples of resin films that can be used as a third substrate include polyester resins, polyamide resins, epoxy resins, acrylic resins, fluororesins, polyurethane resins, silicon resins, phenolic resins, and resin films such as mixtures and copolymers thereof. Among these, polyester resins and polyamide resins are preferred, and biaxially oriented polyester resins and biaxially oriented polyamide resins are more preferred. Specific examples of polyester resins include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, copolymer polyester, and polycarbonate. Specific examples of polyamide resins include nylon 6, nylon 6,6, copolymers of nylon 6 and nylon 6,6, nylon 6,10, and polymetaxylylene adipamide (MXD6).

[0084] The coating layer can be formed from, for example, polyvinylidene chloride, polyester resin, urethane resin, acrylic resin, epoxy resin, etc. It is preferable to form it with a two-component curing resin. Examples of two-component curing resins for forming the coating layer include two-component curing urethane resin, two-component curing polyester resin, and two-component curing epoxy resin. A matting agent may also be incorporated into the coating layer.

[0085] Examples of matting agents include fine particles with a particle size of approximately 0.5 nm to 5 μm. The material of the matting agent is not particularly limited, but examples include metals, metal oxides, inorganic substances, organic substances, etc. The shape of the matting agent is also not particularly limited, but examples include spherical, fibrous, plate-like, amorphous, balloon-like, etc. Specific examples of matting agents include talc, silica, graphite, kaolin, montmorilloid, montmorillonite, synthetic mica, hydrotalcite, silica gel, zeolite, aluminum hydroxide, magnesium hydroxide, zinc oxide, magnesium oxide, aluminum oxide, neodymium oxide, antimony oxide, titanium dioxide, 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, crosslinked acrylic, crosslinked styrene, crosslinked polyethylene, benzoguanamine, gold, aluminum, copper, nickel, etc. These matting agents may be used individually or in combination of two or more. Among these matting agents, silica, barium sulfate, and titanium dioxide are preferred from the viewpoint of dispersion stability and cost. Furthermore, the matting agents may be subjected to various surface treatments such as insulation treatment and high dispersibility treatment.

[0086] Such a laminate is molded so that when used as a battery, the polyolefin film, which is the first base material, is located inside the third base material, thereby becoming the secondary battery casing material of the present invention. There are no particular restrictions on the molding method, and the following method is one example.

[0087] • Heated pressure air molding method: A method in which battery packaging material is sandwiched between a lower mold having holes for supplying high-temperature, high-pressure air and an upper mold having a pocket-shaped recess, and the recess is formed by supplying air while heating and softening the material. • Preheater flat plate compressed air molding method: A method in which battery packaging material is heated and softened, then sandwiched between a lower mold having holes for supplying high-pressure air and an upper mold having pocket-shaped recesses, and the recesses are formed by supplying air. • Drum-type vacuum forming method: A method in which battery packaging material is partially heated and softened in a heated drum, and then the recesses of a drum having pocket-shaped recesses are vacuumed to form the recesses. • Pin molding method: A method in which the bottom material sheet is heated and softened, and then pressed into place using a mold with pocket-shaped indentations and recesses. • Preheater plug-assisted compressed air molding method: A method in which battery packaging material is heated and softened, then sandwiched between a lower mold having holes for supplying high-pressure air and an upper mold having a pocket-shaped recess, and the recess is formed by supplying air, and a convex-shaped plug is raised and lowered during molding to assist the molding process.

[0088] Since the thickness of the base material after molding is uniform, the preheater plug-assisted compressed air molding method, which is a heated vacuum molding method, is preferred. The battery packaging material obtained in this manner can be suitably used as a battery container for sealing and housing battery elements such as a positive electrode, a negative electrode, and an electrolyte.

[0089] <Battery> The battery of the present invention is obtained by covering a battery element comprising a positive electrode, a negative electrode, and an electrolyte with the battery packaging material of the present invention, such that a flange portion (a region in which sealant layers come into contact with each other) is formed around the periphery of the battery element, with the metal terminals connected to the positive electrode and negative electrode respectively protruding outward, and then heat-sealing the sealant layers of the flange portion to seal it.

[0090] The battery obtained using the battery packaging material of the present invention may be either a primary battery or a secondary battery, but a secondary battery is preferred. The secondary battery is not particularly limited and examples include lithium-ion batteries, lithium-ion polymer batteries, lead-acid batteries, nickel-metal hydride batteries, nickel-cadmium batteries, nickel-iron batteries, nickel-zinc batteries, silver oxide-zinc batteries, metal-air batteries, polyvalent cation batteries, capacitors, and the like. Among these secondary batteries, lithium-ion batteries and lithium-ion polymer batteries are particularly suitable applications for the battery packaging material of the present invention. [Examples]

[0091] The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited thereto. Unless otherwise specified, the composition and other numerical values ​​are based on mass.

[0092] <Adhesive adjustment> (Example 1) The adhesive of Example 1 was prepared by thoroughly stirring 100 parts of hydroxyl-modified polyolefin (A-2), 3.8 parts of polyisocyanate compound (B-2), and 40 parts of toluene.

[0093] (Examples 2-4) Adhesives for Examples 2-4 were prepared in the same manner as in Example 1, except that the formulations were changed as shown in Table 1. (Comparative Examples 1-4) The adhesives for Comparative Examples 1 to 4 were prepared in the same manner as in Example 1, except that the formulations were changed as shown in Table 2.

[0094] The details of the compounds used in the examples and comparative examples are as follows: The solid content of ε-caprolactam and triphenylphosphine is 100%. Hydroxyl-modified polyolefin (A-1): A hydroxyl-modified copolymer of α-olefins with 2 to 20 carbon atoms, crystalline (melting point 73°C, heat of fusion 38 J / g, heat of crystallization 35 J / g), weight-average molecular weight 181,700, hydroxyl value in solution 1.28 mg KOH / g (5.06 mg KOH / g on a solid content basis), solid content 25.3%. Hydroxyl-modified polyolefin (A-2): A hydroxyl-modified copolymer of α-olefins with 2 to 20 carbon atoms, crystalline (melting point 74°C, heat of fusion 36 J / g, heat of crystallization 31 J / g), weight-average molecular weight 202,400, hydroxyl value in solution 5.25 mg KOH / g (20.75 mg KOH / g on a solid content basis), solid content 25.3%. Hydroxyl-modified polyolefin (A-3): A hydroxyl-modified copolymer of α-olefins with 2 to 20 carbon atoms, crystalline (melting point 96°C, heat of fusion 45 J / g, heat of crystallization 2 J / g), weight-average molecular weight 172,000, hydroxyl value in solution 4.16 mg KOH / g (solids hydroxyl value 20.8 mg KOH / g), solids content 20%. Hardlen N2002: Acid-modified olefin resin, crystalline, solids content 20%. Unistol P-901: Hydroxyl-modified olefin resin, non-crystalline, hydroxyl value in solution is 11.0 mg KOH / g (50.0 mg KOH / g in terms of solid content), solid content is 22%. Unistol P-902: Acid-modified olefin resin, non-crystalline, solids content 22%. Unistol P-802: Acid-modified olefin, solid content 22%. Polyisocyanate compound (B-1): Nurate of hexamethylene diisocyanate, NCO% is 21.8%, solids content is 100%. Polyisocyanate compound (B-2): Biuret form of hexamethylene diisocyanate, NCO% is 20.7%, solids content is 90%. Denacol EX-321L: Manufactured by Nagase ChemteX Co., Ltd., trimethylolpropane polyglycidyl ether type epoxy resin, epoxy equivalent 130, solids content 100%.

[0095] Furthermore, the presence or absence of crystallinity of the hydroxyl-modified polyolefin (A) used in the examples and comparative examples was determined by DSC (differential scanning calorimetry), which involved heating from -50°C to 200°C at 10°C / min, then cooling to -50°C at 10°C / min to remove the thermal history, and finally heating again to 200°C at 10°C / min. The determination was based on whether or not a peak was observed during the second heating cycle.

[0096] <Laminate> (Example 1) The adhesive from Example 1 was applied to the glossy surface of chromate-treated aluminum foil (film thickness: 40 μm) using a bar coater at a rate of 4 g / m². 2The material was applied (dry) and dried at 80°C for 1 minute, then bonded to an unstretched polyolefin film (film thickness: 40 μm) at 100°C. Next, an adhesive was prepared by mixing "DIC Dry LX-906" (manufactured by DIC Corporation) as the main component and "KW-75" (manufactured by DIC Corporation) as the hardener, with a weight ratio of main component / hardener = 100 / 10, and applied to the matte surface of the aluminum foil using a bar coater at a rate of 4 g / m². 2 After coating (dry), a 25 μm thick stretched polyamide film was laminated. Then, curing (aging) was performed at 40°C for 5 days to obtain the laminate of Example 1.

[0097] (Examples 2-4) An adhesive was prepared in the same manner as in Example 1, except that the adhesive used for bonding the aluminum foil and the unstretched polyolefin film was changed, and a laminate was obtained.

[0098] (Comparative Examples 1-4) An adhesive was prepared in the same manner as in Example 1, except that the adhesive used for bonding the aluminum foil and the unstretched polyolefin film was changed, and a laminate was obtained.

[0099] <Rating> (Measurement of initial adhesive strength) The adhesive strength between laminated aluminum foil and unstretched polyolefin film was evaluated using Shimadzu Corporation's "Autograph AGS-J" under conditions of a peeling speed of 50 mm / min, a peeling width of 15 mm, and a peeling orientation of 180°. The unit is N / 15 mm.

[0100] (Solvent-resistant (wet)) As a solvent, the aged laminate was immersed in a 30g mixed solvent of ethylene carbonate / dimethyl carbonate / ethyl methyl carbonate (1 / 1 / 1) at 50°C for one day. After removing the laminate, the adhesive strength between the aluminum foil and the unstretched polyolefin film of the laminate was measured under conditions of a peeling speed of 50 mm / min, a peeling width of 15 mm, and a peeling orientation of 180°. The unit is N / 15 mm.

[0101] [Table 1]

[0102] [Table 2]

[0103] As is clear from Tables 1 and 2, the adhesive of the present invention has superior initial adhesive strength and solvent resistance compared to the adhesives of the comparative examples. [Industrial applicability]

[0104] The adhesive of the present invention exhibits excellent adhesion and heat resistance between non-polar substrates such as olefin resins and metal substrates. Laminates obtained using the adhesive of the present invention can be suitably used, for example, in battery packaging materials. Furthermore, the applications of the adhesive of the present invention are not limited to battery packaging materials and laminates therefor, but can be widely used in fields where adhesion between non-polar substrates and metal substrates is required, such as home appliance casings, furniture materials, and building interior components.

Claims

1. A composition (X) comprising a hydroxyl-modified polyolefin (A) and a composition (Y) comprising a polyisocyanate compound (B), wherein the hydroxyl-modified polyolefin (A) is crystalline, is a polymer of α-olefin having 2 to 20 carbon atoms, has a melting point of 40°C to 100°C, a heat of fusion of 0 J / g to 50 J / g, a heat of crystallization of 1 J / g to 60 J / g, and a solids hydroxyl value of 0.1 mg KOH / g to 30 mg KOH / g. The polyisocyanate compound (B) contains 80% by mass or more of hexamethylene diisocyanate and compounds derived from hexamethylene diisocyanate, and is a two-component curing adhesive for lithium-ion battery casing materials.

2. The two-component curing adhesive for lithium-ion battery casing material according to claim 1, wherein the weight-average molecular weight of the hydroxyl-modified polyolefin (A) is 10,000 or more and 500,000 or less.

3. The two-component curing adhesive for lithium-ion battery casing materials according to claim 1, wherein the hydroxyl-modified polyolefin (A) contains constituent units derived from propylene.

4. The two-component curing adhesive for lithium-ion battery casing materials according to claim 1, wherein the hydroxyl group-modified polyolefin (A) contains a constituent unit derived from 1-butene.

5. The two-component curing adhesive for lithium-ion battery casing material according to claim 1, wherein the molar ratio [NCO] / [OH] of isocyanate groups contained in composition (Y) to hydroxyl groups contained in composition (X) is 0.5 or more and 5.0 or less.

6. A two-component curing adhesive for lithium-ion battery casing materials according to claim 1, comprising acid-modified polyolefin (C).

7. A two-component curing adhesive for lithium-ion battery casing materials according to claim 1, comprising a polyolefin (D) that does not have reactive functional groups.

8. A two-component curing adhesive for lithium-ion battery casing materials according to claim 1, comprising a silane coupling agent (E-1).

9. A two-component curing adhesive for lithium-ion battery casing materials according to claim 1, comprising a urethane catalyst (E-2).

10. A two-component curing adhesive for lithium-ion battery casing materials according to claim 1, comprising a tackifier (E-3).

11. A two-component curing adhesive for lithium-ion battery casing materials according to claim 1, comprising a thermoplastic elastomer (E-4).

12. A two-component curing adhesive for lithium-ion battery casing materials according to claim 1, comprising epoxy resin (E-5).

13. A laminate for lithium-ion battery casing material, comprising a first substrate, a second substrate, and an adhesive layer for bonding the first substrate and the second substrate, wherein the adhesive layer is a cured coating film of a two-component curing adhesive as described in any one of claims 1 to 12.

14. A packaging material for lithium-ion batteries, obtained by molding the laminate described in claim 13.

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