WO2018008767A1

WO2018008767A1 - Battery exterior material and battery

Info

Publication number: WO2018008767A1
Application number: PCT/JP2017/025078
Authority: WO
Inventors: 純景山; 陽祐早川; 山下　力也
Original assignee: 大日本印刷株式会社
Priority date: 2016-07-08
Filing date: 2017-07-10
Publication date: 2018-01-11
Also published as: JPWO2018008767A1; JP7188079B2; CN109417133A; CN109417133B

Abstract

The present invention provides a battery exterior material capable of decreasing defects caused by inconsistencies in the external appearance thereof in a heat sealing step during battery production. The present invention is a battery exterior material comprising a surface protective layer, a base material layer, an adhesive layer, a barrier layer, and a thermal fusible resin layer which are layered sequentially. When the battery exterior material is heat-sealed under the conditions of 190°C, 1.0 MPa, and 6 seconds while in a state in which the thermal fusible resin layers are facing one another, the difference between the specular gloss according to JIS Z 8741 (1997) of a heat-sealed portion of the surface protective layer and the specular gloss according to JIS Z 8741 (1997) of a non-heat sealed portion of the surface protective layer is less than 1.8.

Description

Battery exterior material and battery

The present invention relates to a battery exterior material and a battery.

Conventionally, as a battery exterior material, a laminate material obtained by laminating a metal container (metal can container) formed by drawing metal into a cylindrical shape or a rectangular tube shape, and a resin layer and a metal foil layer (mainly aluminum foil). A cold-drawn laminated container is used, but a battery using a laminate (laminated battery) is suitable for weight reduction and volume density improvement.

In such a laminate type battery, a battery exterior material having a surface resin layer with an irregular shape on the surface by adding a filler to the outer surface of the base material layer was developed for the purpose of imparting a matte feeling and improving moldability. (See, for example, Patent Documents 1 and 2).
Such a conventional battery exterior material is heat sealed to form a package that accommodates the battery element. However, the surface glossiness of the surface resin layer of the heat seal portion depends on the heat and pressure during heat sealing. It sometimes rose.
However, the conventional battery exterior material has a gloss difference between the heat seal portion and the non-heat seal portion in the vicinity of the battery exterior material after the battery element is accommodated, and the appearance is impaired, resulting in a defective product. This problem was not taken into account at all.

Japanese Patent No. 5594423 International Publication No. 2012/133663

The present invention has been made in view of the above-described situation, and an object of the present invention is to provide a battery exterior material that can reduce defects due to the appearance mismatch of the battery exterior material after housing the battery, and a battery using the battery exterior material. It is what.

The present invention is a battery exterior material comprising a surface protective layer, a base material layer, an adhesive layer, a barrier layer and a heat-fusible resin layer in order from the outside, wherein the heat-fusible resin layers are opposed to each other. The surface gloss of the surface protective layer according to JIS Z 8741 (1997) of the heat protective part of the surface protective layer when heat sealed under conditions of 190 ° C. and 1.0 MPa for 6 seconds This is a battery exterior material having a difference from the specular glossiness of less than 1.8 in accordance with JIS Z 8741 (1997) of the non-heat seal portion.

In the battery exterior material of the present invention, the surface protective layer has irregularities on the surface opposite to the substrate layer side, and when the arithmetic average roughness of the irregularities is Ra, Ra is the following formula: It is preferable to satisfy.
0.20 μm ≦ Ra ≦ 0.50 μm
The surface protective layer preferably contains a filler, and the filler includes titanium oxide, silica, talc, clay, heavy calcium carbonate, light calcium carbonate, barium sulfate, calcium silicate, synthetic silicate, It is preferable that the inorganic filler is made of at least one selected from the group consisting of aluminum hydroxide and silicate fine powder.

Further, a battery in which a battery element including at least a positive electrode, a negative electrode, and an electrolyte is accommodated in a package including a heat seal portion formed of a battery exterior material, and the heat seal portion of the package There is also a battery in which the difference between the specular gloss according to JIS Z 8741 (1997) and the specular gloss according to JIS Z 8741 (1997) of the non-heat-sealed portion of the package is less than 1.8 Further, it is one of the present inventions.
Hereinafter, the present invention will be described in detail.
In the present specification, the numerical range indicated by “to” means “above” or “below”, except where the numerical ranges are clearly stated as “above” or “below”. For example, 2 to 15 mm means 2 mm or more and 15 mm or less.

As a result of intensive studies, the present inventors have focused on the amount of change in the glossiness of the surface protective layer of the battery exterior material by heat sealing. In other words, when heat sealing is performed with the heat sealing resin layers of the battery packaging material facing each other, the amount of change in glossiness between the heat sealing portion and the non-heat sealing portion is controlled within a predetermined range. As a result, it was found that defects due to inconsistency in appearance can be reduced in the heat sealing step when forming a package for housing battery elements, and the present invention has been completed.

Since the battery exterior material of the present invention has the above-described configuration, it is possible to reduce defects due to appearance mismatch in the heat sealing process during battery manufacture.
For this reason, the battery exterior material of this invention can be used conveniently for the battery container excellent in the external appearance.

It is a figure which shows an example of the cross-section of the battery exterior material of this invention.

As shown in FIG. 1, the battery packaging material 10 of the present invention includes a surface protective layer 11, a base material layer 12, an adhesive layer 13, a barrier layer 14, and a heat-fusible resin layer 15 in order from the outside. ing. In addition, FIG. 1 is a figure which shows an example of the cross-sectional structure of the battery exterior material of this invention.
In the battery outer packaging material 10 of the present invention, when the battery is used, the surface protective layer 11 is the outermost layer, and the heat-fusible resin layer 15 is the innermost layer. That is, at the time of assembling the battery, the battery element is sealed by heat-sealing the heat-fusible resin layers 15 located on the periphery of the battery element to seal the battery element. That is, the “outer side” is the side opposite to the side on which the battery element is sealed when the battery is configured using the battery packaging material of the present invention.

The battery exterior material of the present invention has a change in glossiness of the surface protective layer when heat sealed under the conditions of 190 ° C., 1.0 MPa, 6 seconds with the heat-fusible resin layers facing each other. That is, the difference between the mirror glossiness according to JIS Z 8741 (1997) of the heat seal portion and the mirror glossiness according to JIS Z 8741 (1997) of the non-heat seal portion of the surface protective layer is It is less than 1.8. If the difference in specular gloss is 1.8 or more, the difference in gloss between the heat-sealed portion and the non-heat-sealed portion becomes large, causing a defect due to appearance mismatch. The difference in specular gloss after the heat sealing is preferably 1.0 or less.
Specifically, the heat sealing was performed using a heat sealer TP-701-B manufactured by Tester Sangyo Co., Ltd. under the conditions of 190 ° C., 1.0 MPa, and 6 seconds.
The specular gloss is obtained by using a 60-degree specular gloss method in accordance with JIS Z 8741 (1997). Specifically, the gloss measuring instrument Micro-Tri-Gloss manufactured by Toyo Seiki Seisakusho Co., Ltd. Can be measured.
The “non-heat-sealed portion” means a portion other than the portion where heat-sealing is performed in the surface protective layer, and the “non-heat-sealed portion” means the surface of the battery exterior material before being heat-sealed. It can be regarded as a protective layer.
The amount of change in the specular gloss of the surface protective layer after such heat sealing is compared with the conventional specular gloss on the surface protective layer side in the battery outer packaging material of the present invention described above. It can be preferably satisfied by setting a larger value. Further, the amount of change in the specular gloss is controlled by heating the resin contained in the surface protective layer, controlling the softness when pressed to prevent the filler from sinking, and heating the filler. It is possible to prevent the filler from being crushed by controlling the softness when pressed.
When assembling a battery using the battery outer packaging material of the present invention, heat sealing is performed from the surface protective layer side with the heat-fusible resin layers facing each other. Since the amount of change in the glossiness of the surface protective layer after heat sealing satisfies the above-mentioned requirements, it is possible to prevent the gloss difference between the heat seal portion and the non-heat seal portion from increasing and causing a defect due to appearance mismatch.

In the battery outer packaging material of the present invention, the surface protective layer has a role of imparting a matte feeling to the battery outer packaging material of the present invention, and the specular gloss of such a surface protective layer is 3.0. It is preferable that it is 11.0 or less. When the specular gloss on the surface protective layer side is less than 3.0, there is a difference in gloss between the heat-sealed portion and the other (hereinafter also referred to as non-heat-sealed portion) during heat sealing of the battery outer packaging material of the present invention. It may become large and cause defects due to appearance mismatch. On the other hand, when the mirror glossiness on the surface protective layer side exceeds 11.0, the matte feeling may be insufficient and the glossiness of the battery outer packaging material of the present invention may be increased. The more preferable lower limit of the specular gloss on the surface protective layer side is 3.5, the more preferable upper limit is 8.0, the still more preferable lower limit is 3.6, the still more preferable upper limit is 6.5, and the particularly preferable upper limit is 5. 4. In addition, the specular glossiness of the said surface protective layer is a specular glossiness in a non-heat-sealed part when heat-sealing to the battery exterior material of this invention on the conditions mentioned above.
In addition, the battery exterior material provided with the conventional matte feeling is given a matte feeling mainly from the viewpoint of moldability, and the above-mentioned specular gloss is often about 2.0. Compared to the material, the matte feeling was less glossy and stronger.
In the battery exterior material of the present invention, the difference in specular gloss between the heat seal portion and the non-heat seal portion is preferably 1.0 or less, more preferably 0.8 or less, and even more preferably 0.5 or less. If the difference in specular gloss between the heat seal part and the non-heat seal part exceeds 1.0, the difference in gloss between the heat seal part and the non-heat seal part becomes large, and it is determined that the appearance is poor. There is.

The surface protective layer has irregularities on the surface opposite to the base material layer side, and when the arithmetic average roughness of the irregularities on the surface of the surface protective layer is Ra, the Ra satisfies the following formula: Is preferred.
0.20 μm ≦ Ra ≦ 0.50 μm
If the Ra is less than 0.20 μm, the specular gloss of the surface protective layer may increase and a desired matte feeling may not be obtained. If the Ra exceeds 0.50 μm, the surface protective layer after heat sealing The amount of change in specular gloss may be large. The more preferable lower limit of Ra is 0.24 μm, the more preferable upper limit is 0.42 μm, the still more preferable lower limit is 0.30 μm, and the more preferable upper limit is 0.37 μm.
The arithmetic average roughness Ra of the surface protective layer is a value obtained by photographing the surface of the surface protective layer and using the image processing software VK Analyzer of Keyence Co., Ltd. from the photographed image.

The surface protective layer preferably contains a filler.
By containing the filler, an uneven shape can be formed on the surface of the surface protective layer, and a matte feeling can be imparted to the battery outer packaging material of the present invention. Examples of means for forming irregularities on the surface of the surface protective layer include, for example, means for shaping with an embossed plate having an irregular shape, means for containing a filler in the composition constituting the surface protective layer, and the like. However, for reasons such as production cost, a means for containing a filler in the composition constituting the surface protective layer is preferable.
The filler is not particularly limited, but from titanium oxide, silica, talc, clay, heavy calcium carbonate, light calcium carbonate, barium sulfate, calcium silicate, synthetic silicate, aluminum hydroxide, and fine powder of silicate. It is preferable that the inorganic filler is made of at least one selected from the group consisting of:
Examples of the organic filler include fillers made of high melting point nylon, crosslinked acrylic, crosslinked styrene, crosslinked polyethylene, benzoguanamine and the like. Although it does not specifically limit as a shape of the said organic filler, For example, spherical shape, fibrous shape, plate shape, an indeterminate form, and balloon shape are mentioned.

Among the inorganic fillers, an inorganic filler made of silica or precipitated barium sulfate is preferable because it is easy to handle and easily available.
The precipitated barium sulfate refers to barium sulfate produced using a chemical reaction, and is characterized in that the particle size can be controlled.

As content of the said filler, it adjusts suitably in the range with which the requirements of the specular glossiness by the surface protective layer side in the battery exterior material of this invention mentioned above are satisfy | filled. Specifically, when the filler is silica having an average particle size of 1.0 μm or more and 3.0 μm or less, it is preferably 2.0% by mass or more and 8.7% by mass or less in the surface protective layer, When the filler is precipitated barium sulfate having an average particle size of less than 1.0 μm, it is preferably 13.0% by mass or more and 40.0% by mass or less in the surface protective layer.
In addition, the said filler content is content of the filler in the said surface protective layer, and is content after the solvent volatilizes from the resin composition mentioned later for forming this surface protective layer.

The surface protective layer preferably contains the filler in the resin component.
The resin component preferably includes a thermosetting resin, and any thermosetting resin may be used as long as it causes polymerization upon heating to form a polymer network structure and cure.
Specific examples of the thermosetting resin include epoxy resins, amino resins (melamine resins, benzoguanamine resins, etc.), acrylic resins, urethane resins, phenol resins, unsaturated polyester resins, alkyd resins, and the like.

Among these thermosetting resins, urethane resins and epoxy resins are preferable from the viewpoints of shortening the curing time, improving moldability and chemical resistance, and more preferably two-component curable urethane resins and 2 A liquid curable epoxy resin is mentioned, Especially preferably, a 2 liquid curable epoxy resin is mentioned.

Specific examples of the two-component curable urethane resin include a combination of a polyol compound (main agent) and an isocyanate compound (curing agent), and the two-component curable epoxy resin specifically includes an epoxy resin ( And a combination of an acid anhydride, an amine compound, or an amino resin (curing agent).
Moreover, as said 2 liquid curable urethane resin, the polyfunctional urethane (meth) acrylate which consists of a combination of the polyfunctional (meth) acrylate (main ingredient) which has active hydrogen, and polyisocyanate (curing agent) is also preferable.

In the two-component curable urethane resin, the polyol compound used as the main agent is not particularly limited, and examples thereof include polyester polyol, polyester polyurethane polyol, polyether polyol, and polyether polyurethane polyol. These polyol compounds may be used individually by 1 type, and may be used in combination of 2 or more type.

In the two-component curable urethane resin, the isocyanate compound used as a curing agent is not particularly limited. For example, polyisocyanate, its adduct, its isocyanurate modified, its carbodiimide modified, its allophanate modified. Body, its modified burette and the like.
Specific examples of the polyisocyanate include diphenylmethane diisocyanate (MDI), polyphenylmethane diisocyanate (polymeric MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), and bis (4-isocyanatocyclohexyl) methane (H12MDI). , Aromatic diisocyanates such as isophorone diisocyanate (IPDI), 1,5-naphthalene diisocyanate (1,5-NDI), 3,3′-dimethyl-4,4′-diphenylene diisocyanate (TODI), xylene diisocyanate (XDI) Aliphatic diisocyanates such as tramethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, isophorone diisocyanate DOO; 4,4'-methylenebis (cyclohexyl isocyanate), alicyclic diisocyanates such as isophorone diisocyanate; 1,5-naphthalene diisocyanate (1, 5-NDI) polycyclic aromatic diisocyanates such as are exemplified.
Specific examples of the adduct include those obtained by adding trimethylolpropane, glycol and the like to the polyisocyanate.
These isocyanate compounds may be used individually by 1 type, and may be used in combination of 2 or more type.

These thermosetting resins may be crosslinkable elastomers. A crosslinkable elastomer is a thermosetting resin that can impart a soft segment to a cured product. For example, in the case of a two-component curable urethane resin or a two-component curable epoxy resin among crosslinkable elastomers, the above-described main agent only needs to have a structure capable of imparting a soft segment.
The crosslinkable elastomer is used as a part of a thermosetting resin used for forming a layer constituting the surface protective layer in order to provide the layer constituting the surface protective layer with a desired hardness. Can do.

These thermosetting resins may be used individually by 1 type, and may be used in combination of 2 or more type.
The surface protective layer may be formed of a plurality of layers. When the surface protective layer is formed of a plurality of layers, the thermosetting resin used in each layer may be the same or different, and the type of thermosetting resin is a function to be provided in each layer. It may be appropriately selected according to the physical properties and the like. For example, among the layers constituting the surface protective layer, the layer that forms the outermost layer (the outermost layer located on the side opposite to the base layer) has a polycyclic aroma from the viewpoint of having excellent chemical resistance. A thermosetting resin having a group skeleton and / or a heterocyclic skeleton is preferably used.
Specific examples of the thermosetting resin having a polycyclic aromatic skeleton include an epoxy resin having a polycyclic aromatic skeleton and a urethane resin having a polycyclic aromatic skeleton.
Specific examples of the thermosetting resin having the heterocyclic skeleton include amino resins such as melamine resin and benzoguanamine resin.
These thermosetting resins having a polycyclic aromatic skeleton and / or a heterocyclic skeleton may be either a one-component curable type or a two-component curable type.

More specifically, the epoxy resin having a polycyclic aromatic skeleton includes a reaction product of dihydroxynaphthalene and epihalohydrin; a condensate of naphthol and aldehydes (naphthol novolak resin) and a reaction product of epihalohydrin; Condensate of dihydroxynaphthalene and aldehyde and reaction product of epihalohydrin; condensate of mono- or dihydroxynaphthalene and xylylene glycol and reaction product of epihalohydrin; adduct of mono- or dihydroxynaphthalene and diene compound And a reaction product of epihalohydrin; a reaction product of polynaphthols in which naphthols are directly coupled to epihalohydrin, and the like.

More specifically, examples of the urethane resin having a polycyclic aromatic skeleton include a reaction product of a polyol compound and an isocyanate compound having a polycyclic aromatic skeleton.

(Curing accelerator)
The resin composition forming the surface protective layer may further contain a curing accelerator in addition to the filler and the resin component described above.
By coexisting a curing accelerator together with the thermosetting resin, the surface protective layer can be cured in a short time without requiring aging under high temperature conditions during production to form a layer having the specific hardness. it can.

Here, the “curing accelerator” is a substance that does not form a crosslinked structure by itself, but promotes the crosslinking reaction of the thermosetting resin, and has the effect of promoting the crosslinking reaction of the thermosetting resin. Is also a substance that may form a crosslinked structure.

The type of the curing accelerator is appropriately selected according to the thermosetting resin to be used so that the above-described hardness can be satisfied. For example, an amidine compound, a carbodiimide compound, a ketimine compound, a hydrazine compound, a sulfonium salt, Examples thereof include benzothiazolium salts and tertiary amine compounds.

The amidine compound is not particularly limited. For example, imidazole compound, 1,8-diazabicyclo [5.4.0] undec-7ene (DBU), 1,5-diazabicyclo [4.3.0] none-5 -Ene (DBN), guanidine compounds and the like.
Specific examples of the imidazole compound include 2-methylimidazole, 2-ethylimidazole, 2-undecylimidazole, 2,4-dimethylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 1,2 -Diethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-benzyl- 2-methylimidazole, 2,4-diamino-6- [2′-methylimidazolyl- (1) ′]-ethyl-S-triazine, 2,4-diamino-6- [2′-ethyl-4′-methyl Imidazolyl- (1) ′]-ethyl-S-triazine, 2,4-diamino- -[2'-undecylimidazolyl] -ethyl-S-triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1) ']-ethyl-S-triazine isocyanur oxidation adduct, 2- Examples include phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-aryl-4,5-diphenylimidazole and the like. These amidine compounds may be used individually by 1 type, and may be used in combination of 2 or more type.

The carbodiimide compound is not particularly limited. For example, N, N′-dicyclohexylcarbodiimide, N, N′-diisopropylcarbodiimide, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide, N- [3- (dimethyl Amino) propyl] -N′-ethylcarbodiimide, N- [3- (dimethylamino) propyl] -N′-ethylcarbodiimide methiodide, N-tert-butyl-N′-ethylcarbodiimide, N-cyclohexyl-N ′ -(2-morpholinoethyl) carbodiimide meso-p-toluenesulfonate, N, N'-di-tert-butylcarbodiimide, N, N'-di-p-tolylcarbodiimide and the like. These carbodiimide compounds may be used individually by 1 type, and may be used in combination of 2 or more type.

The ketimine compound is not particularly limited as long as it has a ketimine bond (N = C), and examples thereof include a ketimine compound obtained by reacting a ketone with an amine.
Specific examples of the ketone include methyl ethyl ketone, methyl isopropyl ketone, methyl tertiary butyl ketone, methyl cyclohexyl ketone, diethyl ketone, ethyl propyl ketone, ethyl butyl ketone, dipropyl ketone, dibutyl ketone, and diisobutyl ketone. It is done.
Specific examples of the amine include aromatic polyamines such as o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, m-xylylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, and diaminodiethyldiphenylmethane. Ethylenediamine, propylenediamine, butylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexamethylenediamine, trimethylhexamethylenediamine, 1,2-propanediamine, iminobispropylamine, methyliminobispropylamine Monoamines having an ether bond in the main chain, such as N-aminoethylpiperazine, 3-butoxyisopropylamine, etc. Polyether skeleton diamines; cycloaliphatic polyamines such as isophorone diamine, 1,3-bisaminomethylcyclohexane, 1-cyclohexylamino-3-aminopropane, 3-aminomethyl-3,3,5-trimethylcyclohexylamine: norbornane Skeletal diamine; Polyamidoamine having an amino group at the molecular end of polyamide; 2,5-dimethyl-2,5-hexamethylenediamine, mensendiamine, 1,4-bis (2-amino-2-methylpropyl) piperazine Etc. are mentioned as specific examples. These ketimine compounds may be used individually by 1 type, and may be used in combination of 2 or more type.

The hydrazine compound is not particularly limited, and examples thereof include dipic acid dihydrazide and isophthalic acid dihydrazide. These hydrazine compounds may be used individually by 1 type, and may be used in combination of 2 or more type.

The sulfonium salt is not particularly limited. For example, 4-acetophenyldimethylsulfonium hexafluoroantimonate, 4-acetophenyldimethylsulfonium hexafluoroarsenate, dimethyl-4- (benzyloxycarbonyloxy) phenylsulfonium hexafluoroantimonate Alkylsulfonium salts such as dimethyl-4- (benzoyloxy) phenylsulfonium hexafluoroantimonate and dimethyl-4- (benzoyloxy) phenylsulfonium hexafluoroarsenate; benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 4 -Acetoxyphenylbenzylmethylsulfonium hexafluoroantimonate, benzyl-4-methoxyphenyl Benzylsulfonium salts such as tilsulfonium hexafluoroantimonate, benzyl-3-chloro-4-hydroxyphenylmethylsulfonium hexafluoroarsenate, 4-methoxybenzyl-4-hydroxyphenylmethylsulfonium hexafluorophosphate; dibenzyl-4-hydroxyphenyl Dibenzylsulfonium such as sulfonium hexafluoroantimonate, dibenzyl-4-hydroxyphenylsulfonium hexafluorophosphate, dibenzyl-4-methoxyphenylsulfonium hexafluoroantimonate, benzyl-4-methoxybenzyl-4-hydroxyphenylsulfonium hexafluorophosphate Salt; p-chlorobenzyl-4-hydroxyphenylmethylsulfonium hexaf Oroantimonate, p-nitrobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 3,5-dichlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, o-chlorobenzyl-3-chloro-4-hydroxy Examples thereof include substituted benzylsulfonium salts such as phenylmethylsulfonium hexafluoroantimonate. These sulfonium salts may be used individually by 1 type, and may be used in combination of 2 or more type.

The benzothiazolium salt is not particularly limited. For example, 3-benzylbenzothiazolium hexafluoroantimonate, 3-benzylbenzothiazolium hexafluorophosphate, 3-benzylbenzothiazolium tetrafluoroborate, 3 Benzyl such as-(p-methoxybenzyl) benzothiazolium hexafluoroantimonate, 3-benzyl-2-methylthiobenzothiazolium hexafluoroantimonate, 3-benzyl-5-chlorobenzothiazolium hexafluoroantimonate A benzothiazolium salt is mentioned. These benzothiazolium salts may be used individually by 1 type, and may be used in combination of 2 or more type.

The tertiary amine compound is not particularly limited, and examples thereof include trimethylamine, triethylamine, tripropylamine, tributylamine, triethylenediamine, 1,4-diazabicyclo [2.2.2] octane, quinuclidine, and 3-quinuclidinol. Aliphatic tertiary amines; aromatic tertiary amines such as dimethylaniline; and heterocyclic tertiary amines such as isoquinoline, pyridine, collidine, and betapicoline. These tertiary amine compounds may be used individually by 1 type, and may be used in combination of 2 or more type.

As a suitable example of the said hardening accelerator, what functions as a thermal acid generator is mentioned.
The thermal acid generator is a substance that generates an acid by heating and functions as a curing accelerator. Specific examples of the curing accelerator that can function as a thermal acid generator include a sulfonium salt and a benzothiazolium salt.

Another preferable example of the curing accelerator is a thermal latent that is activated under a predetermined heating condition (for example, 80 to 200 ° C., preferably 100 to 160 ° C.) to promote the crosslinking reaction of the thermosetting resin. The thing with sex is mentioned. Specific examples of the heat-latent substance among the above-described curing accelerators include epoxy adducts in which an epoxy compound is added to an amidine compound, a hydrazine compound, a tertiary amine compound, or the like.

Furthermore, as another suitable example of the curing accelerator, it does not function as a curing agent in a sealed state, that is, a moisture blocking state, but the sealed state is opened and hydrolyzed under the presence of moisture as a curing agent. Those having a hydrolytic potential that functions.
Among the above-mentioned curing accelerators, specific examples of the hydrolytic latent substance include an epoxy adduct obtained by adding an epoxy compound to an amidine compound, a hydrazine compound, a tertiary amine compound, or the like.

These hardening accelerators may be used individually by 1 type, and may be used in combination of 2 or more type. Among these curing accelerators, an amidine compound and a sulfonium salt are preferable, and an amidine compound is more preferable.

These hardening accelerators may be used individually by 1 type in the said surface protective layer, and may be used in combination of 2 or more type.
Further, when the surface protective layer is formed of a plurality of layers, the curing accelerator used in each layer constituting the surface protective layer may be the same or different. May be appropriately selected according to the function and physical properties to be provided in each layer.

When the curing accelerator is used, the content of the curing accelerator in the resin composition used for forming the surface protective layer is appropriately set according to the type of thermosetting resin to be used, the type of curing accelerator, and the like. However, for example, the total amount of the curing accelerator is 0.01 to 6 parts by weight, preferably 0.05 to 5 parts by weight, more preferably 0.1 to 2 parts by weight with respect to 100 parts by weight of the thermosetting resin. Part.

(Pigment / Dye)
The surface protective layer may contain at least one of a pigment and a dye as necessary.
When the surface protective layer contains at least one of a pigment and a dye, whitening at the time of molding can be more effectively suppressed, and wear resistance can be improved. Further, when the surface protective layer contains at least one of a pigment and a dye, the battery exterior material of the present invention can be given distinctiveness (colored by at least one of the pigment and the dye), and the battery exterior material of the present invention. It is possible to impart a matte design to the surface of the battery or to further improve the heat dissipation by increasing the thermal conductivity of the battery exterior material of the present invention.

The material of the pigment is not particularly limited and may be either an inorganic pigment or an organic pigment.
Specific examples of the inorganic pigment include carbon black, carbon nanotube, graphite, kaolin, magnesium hydroxide, zinc oxide, magnesium oxide, aluminum oxide, neodymium oxide, antimony oxide, cerium oxide, calcium sulfate, lithium carbonate, and gold. , Aluminum, copper, nickel and the like.
Specific examples of the organic pigment include azo pigments, polycyclic pigments, lake pigments, and fluorescent pigments.
These pigments may be used alone or in combination of two or more.

The shape of the pigment is not particularly limited, and examples thereof include a spherical shape, a fiber shape, a plate shape, an indeterminate shape, and a balloon shape.
The average particle size of the pigment is not particularly limited, but for example, it is preferably 0.01 to 3 μm, more preferably 0.05 to 1 μm.
The average particle size of the pigment is measured by using a Shimadzu laser diffraction particle size distribution analyzer SALD-2100-WJA1, and using compressed air, the powder to be measured is jetted from a nozzle and dispersed in the air. It is a value measured by an injection type dry measurement method.

The pigment may be subjected to various surface treatments such as an insulation treatment and a high dispersibility treatment (resin coating treatment) on the surface as necessary.

The type of the dye is not particularly limited as long as it can be dissolved and dispersed in the resin composition used for forming the surface protective layer. For example, a nitro dye, an azo dye, a stilbene dye, a carbonium dye Quinoline dyes, methine dyes, thiazole dyes, quinimine dyes, anthraquinone dyes, indigoid dyes, phthalocyanine dyes, and the like, preferably azo dyes, carbonium dyes, anthraquinone dyes, and the like. These dyes may be used alone or in combination of two or more.

Among these pigments and dyes, from the viewpoint of further improving the heat dissipation of the battery packaging material of the present invention, it is preferably a pigment, more preferably an inorganic pigment, more preferably carbon such as carbon black, carbon nanotube, and graphite. Materials, particularly preferably carbon black.

In the case where the surface protective layer has a multilayer structure composed of two or more layers, the pigment and / or dye may be any one of these two or more layers in order to contain the pigment and the like. It may be contained in one layer, or may be contained in two or more layers.
From the viewpoint of reducing the difference in color tone between the molded part and the non-molded part after molding the battery exterior material of the present invention, the surface protective layer has a multilayer structure composed of two or more layers. It is preferable to contain a pigment and / or dye in two or more layers, and the surface protective layer is made into a three-layer structure composed of three layers, and the pigment and / or dye is contained in all three layers. Further preferred.

In the case where a pigment and / or dye is contained in at least one layer constituting the surface protective layer, the content should be given to the type of pigment and / or dye to be used and the battery packaging material of the present invention. What is necessary is just to set suitably according to discriminability, heat dissipation, etc. For example, with respect to 100 mass parts of resin components contained in the layer which contains a pigment and / or dye, a pigment and / or dye are 1-30 in total amount. A mass part is mentioned. From the viewpoint of imparting even better discrimination, the total amount of the pigment and / or dye is 3 to 20 parts by mass with respect to 100 parts by mass of the resin component contained in the layer containing the pigment and / or dye. . In addition, from the viewpoint of suppressing deterioration in moldability due to pigments and / or dyes, together with even better discrimination, with respect to 100 parts by mass of the resin component contained in the layer containing the pigments and / or dyes, The total amount of the pigment and / or dye is 5 to 15 parts by mass.

(Other additives)
In addition to the above-described components, the resin composition used for the formation of the surface protective layer has an organic filler, a slip agent, and a solvent, depending on the functionality to be provided in the surface protective layer. Other additives such as elastomer resins may be included.

When the surface protective layer contains an organic filler or a slip agent, it gives a slip effect to the surface of the battery outer packaging material of the present invention, improves the formability / workability in press molding or embossing, Can be improved.

Although it does not specifically limit as a kind of said organic filler, For example, high melting point nylon, crosslinked acrylic, crosslinked styrene, crosslinked polyethylene, benzoguanamine etc. are mentioned.
The shape of the organic filler is not particularly limited, and examples thereof include a spherical shape, a fiber shape, a plate shape, an indeterminate shape, and a balloon shape.

Moreover, it does not specifically limit as said slip agent, For example, a non-reactive slip agent may be sufficient and a reactive slip agent may be sufficient. In particular, the reactive slip agent is less likely to lose bleed from the outermost surface layer constituting the surface protective layer, and suppresses the occurrence of powder blowing and set-off during use and the reduction of the slip effect over time. Among the slip agents, a reactive slip agent is preferable because of the advantage that it can be used.

Here, the said non-reactive slip agent is a compound which does not have the functional group which reacts with the resin component mentioned above, and couple | bonds chemically, and can provide slip property (slip property), for example. The reactive slip agent is a compound that has a functional group that reacts with the resin component and chemically binds, and can impart slip properties (slip properties).

Specific examples of the non-reactive slip agent include fatty acid amide, metal soap, hydrophilic silicone, silicone grafted acrylic, silicone grafted epoxy, silicone grafted polyether, and silicone grafted polyester. , Block type silicone acrylic copolymer, polyglycerol-modified silicone, paraffin and the like. These non-reactive slip agents may be used individually by 1 type, and may be used in combination of 2 or more type.

Further, in the reactive slip agent, the type of functional group is appropriately set according to the type of resin component used, for example, hydroxyl group, mercapto group, hydrolyzable silyl group, isocyanate group, epoxy group, Examples thereof include a polymerizable vinyl group and a (meth) acryloyl group. In the reactive slip agent, the number of functional groups per molecule is not particularly limited, and examples thereof include 1 to 3, preferably 1 or 2.

Specific examples of the reactive slip agent include modified silicones having the above functional groups; modified fluororesins having the above functional groups; fatty acid amides such as stearic acid amide, oleic acid amide, erucic acid amide, and ethylenebisstearic acid amide. And compounds having the functional group introduced therein; metal soaps having the functional group introduced therein; and paraffins having the functional group introduced therein. These reactive slip agents may be used individually by 1 type, and may be used in combination of 2 or more type.
Among these reactive slip agents, the modified silicone having the functional group, the modified fluororesin having the functional group, and the silicone-modified resin having the functional group are preferable.
Specific examples of the modified silicone include, for example, a modified silicone obtained by block polymerization of a polymer having the above functional group, such as a modified silicone obtained by block polymerization of an acrylic resin; and a modified silicone obtained by graft polymerization of an acrylate. And modified silicone obtained by graft polymerization of a monomer having the above functional group.
As the modified fluororesin, specifically, for example, a modified fluororesin in which a monomer having the above functional group is graft polymerized, such as a fluororesin in which an acrylate is graft polymerized; an acrylic resin is block polymerized Examples thereof include a fluororesin obtained by block polymerization of a polymer having the above functional group, such as a modified fluororesin.
Further, as the silicone-modified resin, specifically, the silicone having the functional group and the graft polymerized, such as a silicone-modified acrylic resin in which the silicone is graft-polymerized to the acrylic resin having the functional group. Examples include silicone-modified resins.
Among these, as a particularly preferable reactive slip agent, a modified silicone in which the monomer or polymer having the functional group is polymerized at one terminal of the silicone; the monomer or polymer having the functional group is fluorine. Examples thereof include a modified fluororesin that is polymerized at one end of the resin. As such modified silicone and modified fluororesin, for example, “Modiper (registered trademark) F / FS series” (manufactured by NOF Corporation), “Symac (registered trademark) series” (manufactured by Toagosei Co., Ltd.) and the like are commercially available. These commercial products can also be used.

When the slip agent is contained in the resin composition used to form the outermost layer in the surface protective layer, the content is not particularly limited, but for example, for 100 parts by mass of the resin component, The total amount of slip agent is 1 to 12 parts by mass, preferably 3 to 10 parts by mass, more preferably 5 to 8 parts by mass.

<Hardness of surface protective layer>
The surface of the surface protective layer of the battery outer packaging material of the present invention preferably has a Martens hardness of 15 N / mm ² or more measured by a load of 1 mN by an indentation method. In the battery outer packaging material of the present invention, since the surface protective layer has such a specific hardness, whitening at the time of forming a package for housing the battery element is effectively suppressed, and the battery is excellent. It has moldability. Also, whitening in view of more effectively suppressing the time of molding, As the hardness, more preferably 18N / mm ² or more, further preferably 20 N / mm ² or more. The upper limit of the Martens hardness is about 25 N / mm ² .
Moreover, when the said surface protective layer has the said Martens hardness, the collapsing of a filler is suppressed effectively and the objective of this invention can be achieved suitably.

In the present invention, a specific method for measuring the Martens hardness of the surface of the surface protective layer is a diamond regular quadrangular pyramid having a diagonal angle of 136 ° from the direction perpendicular to the surface of the surface protective layer (surface opposite to the base material layer). A Vickers indenter having a shape is pushed in, the Martens hardness is calculated from the obtained load-displacement curve, and the average obtained at five locations is the Martens hardness of the surface of the surface protective layer.
More specifically, the Martens hardness is calculated by calculating the surface area A (mm ² ) of a pyramidal depression formed by indentation at the maximum indentation depth h of the Vickers indenter, and dividing the test load F (N) (F / A).
Details of the method for measuring the Martens hardness on the surface of the surface protective layer are as follows.
That is, based on the indentation method, the Martens hardness of the surface protective layer can be measured by pressing an indenter into the surface of the surface protective layer under the following specific conditions. The Martens hardness can be measured by an indentation method using a Picodenter HM-500 manufactured by Fischer Instruments.
<Measurement conditions>
・ Load 1mN
・ Loading speed: 1 mN / 10 seconds ・ Holding time: 10 seconds ・ Loading unloading speed: 1 mN / 10 seconds ・ Indenter Vickers (face angle of the tip of the square pyramid: 136 °)
・ Measurement temperature 25 ℃

The hardness of the surface protective layer can be set to the above-described value by appropriately adjusting the type and amount of the thermosetting resin used for forming the surface protective layer. For example, the desired hardness can be set by appropriately adjusting the amount and type of the crosslinkable elastomer in the thermosetting resin used for forming the surface protective layer.

<Thickness of surface protective layer>
The thickness of the surface protective layer is, for example, about 0.5 to 10 μm, preferably about 1 to 9 μm.

[Base material layer]
In the battery exterior material of the present invention, the base material layer is a layer provided inside the surface protective layer.
The material for forming the base material layer is not particularly limited as long as it has insulating properties.
Examples of the material for forming the base material layer include resin films such as polyester resin, polyamide resin, epoxy resin, acrylic resin, fluorine resin, polyurethane resin, silicon resin, phenol resin, and a mixture or copolymer thereof. Can be mentioned. Among these, Preferably a polyester resin and a polyamide resin are mentioned, More preferably, a biaxially stretched polyester resin and a biaxially stretched polyamide resin are mentioned.
Specific examples of the polyester resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, copolyester, and polycarbonate.
Specific examples of the polyamide resin include nylon 6, nylon 6,6, a copolymer of nylon 6 and nylon 6,6, nylon 6,10, polymetaxylylene adipamide (MXD6), and the like. Can be mentioned.

Although the said base material layer may be formed from the resin film of one layer, in order to improve pinhole resistance and insulation, it may be formed with the resin film of two or more layers.
When the base material layer is formed of a multilayer resin film, two or more resin films may be laminated through an adhesive layer such as an adhesive or an adhesive resin, and the adhesive component used The type and amount are the same as in the case of the adhesive layer described later. In addition, it does not specifically limit as a method of laminating | stacking two or more resin films, A well-known method is employable, For example, a dry lamination method, a sandwich lamination method, etc. are mentioned, Preferably the dry lamination method is mentioned.
When laminating by the dry laminating method, it is preferable to use a urethane-based adhesive as the adhesive layer. At this time, the thickness of the adhesive layer is, for example, about 2 to 5 μm.

The thickness of the base material layer is not particularly limited as long as it functions as a base material layer. Examples thereof include about 1 to 50 μm, preferably about 3 to 25 μm, and more preferably about 3 to 15 μm.

[Adhesive layer]
In the battery exterior material of the present invention, the adhesive layer is a layer provided between the base material layer and the barrier layer as necessary in order to firmly bond the base material layer and the barrier layer.

The adhesive layer is formed of an adhesive that can bond the base material layer and the barrier layer. The adhesive used for forming the adhesive layer may be a two-component curable adhesive or a one-component curable adhesive. Furthermore, the bonding mechanism of the adhesive used for forming the adhesive layer is not particularly limited, and any of a chemical reaction type, a solvent volatilization type, a heat melting type, a hot pressure type, and the like may be used.

Specific examples of the adhesive component that can be used for forming the adhesive layer include polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, polycarbonate, and copolyester; Polyether adhesive; Polyurethane adhesive; Epoxy resin; Phenol resin resin; Polyamide resin such as nylon 6, nylon 66, nylon 12, copolymer polyamide; polyolefin, carboxylic acid modified polyolefin, metal modified polyolefin, etc. Polyolefin resins, polyvinyl acetate resins, cellulose adhesives, (meth) acrylic resins, polyimide resins, urea resins, melamine resins and other amino resins, chloroprene rubber, nitrile rubber, - Len rubbers such as butadiene rubber, silicone-based resins. These adhesive components may be used individually by 1 type, and may be used in combination of 2 or more type. Among these adhesive components, a polyurethane adhesive is preferable.
The adhesive layer may contain a color pigment such as carbon black or titanium oxide in a range that does not hinder the adhesive performance of the adhesive component.

The thickness of the adhesive layer is not particularly limited as long as it functions as an adhesive layer. For example, the thickness is about 1 to 10 μm, preferably about 2 to 5 μm.

[Barrier layer]
In the battery packaging material of the present invention, the barrier layer is a layer that functions as a barrier layer for preventing the penetration of water vapor, oxygen, light, etc. into the battery, in addition to improving the strength of the battery packaging material. . The barrier layer is preferably made of a metal, and specific examples of the metal include aluminum, stainless steel, and titanium, and preferably aluminum.
The barrier layer can be formed of, for example, a metal foil, a metal vapor-deposited film, an inorganic oxide vapor-deposited film, a film provided with these vapor-deposited films, or the like, preferably formed of a metal foil, and formed of an aluminum foil. More preferably. From the viewpoint of preventing the generation of wrinkles and pinholes in the barrier layer during the production of the battery exterior material of the present invention, for example, annealed aluminum (JIS H4160: 1994 A8021H-O, JIS H4160: 1994 A8079H). -O, JIS H4000: 2014 A8021P-O, and JIS H4000: 2014 A8079P-O) are more preferable.

The thickness of the barrier layer is not particularly limited as long as it functions as a barrier layer, and can be, for example, about 10 to 50 μm, preferably about 20 to 40 μm.

The barrier layer is preferably subjected to chemical conversion treatment on at least one surface, preferably both surfaces, for the purpose of stabilizing adhesion, preventing 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 barrier layer. As the chemical conversion treatment, for example, chromate chromate using chromic acid compounds such as chromium nitrate, chromium fluoride, chromium sulfate, chromium acetate, chromium oxalate, chromium biphosphate, chromic acetyl acetate, chromium chloride, potassium sulfate chromium, etc. Treatment: Phosphoric acid chromate treatment using a phosphoric acid compound such as sodium phosphate, potassium phosphate, ammonium phosphate, polyphosphoric acid; aminated phenol having a repeating unit represented by the following general formulas (1) to (4) Examples include chromate treatment using a polymer. In the aminated phenol polymer, the repeating units represented by the following general formulas (1) to (4) may be contained singly or in any combination of two or more. Also good.

In the general formulas (1) to (4), X represents a hydrogen atom, a hydroxyl group, an alkyl group, a hydroxyalkyl group, an allyl group or a benzyl group. R ¹ and R ² are the same or different and each represents a hydroxyl group, an alkyl group or a hydroxyalkyl group.
In the general formulas (1) to (4), examples of the alkyl group represented by X, R ¹ and R ² include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, Examples thereof include a linear or branched alkyl group having 1 to 4 carbon atoms such as a tert-butyl group. Examples of the hydroxyalkyl group represented by X, R ¹ and R ² include a hydroxymethyl group, a 1-hydroxyethyl group, a 2-hydroxyethyl group, a 1-hydroxypropyl group, a 2-hydroxypropyl group, 3- C1-C4 straight or branched chain in which one hydroxy group such as hydroxypropyl group, 1-hydroxybutyl group, 2-hydroxybutyl group, 3-hydroxybutyl group, 4-hydroxybutyl group is substituted An alkyl group is mentioned. In the general formulas (1) to (4), the alkyl group and hydroxyalkyl group represented by X, R ¹ and R ² may be the same or different.
In the general formulas (1) to (4), X is preferably a hydrogen atom, a hydroxyl group or a hydroxyalkyl group.
The number average molecular weight of the aminated phenol polymer having a repeating unit represented by the general formulas (1) to (4) is preferably, for example, 500 to 1,000,000, and preferably about 1,000 to 20,000. More preferred.

Further, as a chemical conversion treatment method for imparting corrosion resistance to the barrier layer, a coating in which metal oxide such as aluminum oxide, titanium oxide, cerium oxide, tin oxide or barium sulfate fine particles are dispersed in phosphoric acid, A method of forming a corrosion-resistant layer on the surface of the barrier layer by performing a baking treatment at 150 ° C. or higher can be mentioned. Further, a resin layer obtained by crosslinking a cationic polymer with a crosslinking agent may be further formed on the corrosion-resistant treatment layer. Here, examples of the cationic polymer include polyethyleneimine, an ionic polymer complex composed of a polymer having polyethyleneimine and a carboxylic acid, a primary amine graft acrylic resin obtained by graft polymerization of a primary amine on an acrylic main skeleton, and polyallylamine. Or the derivative, aminophenol, etc. are mentioned. As these cationic polymers, only one type may be used, or two or more types may be used in combination. Examples of the crosslinking agent include a compound having at least one functional group selected from the group consisting of an isocyanate group, a glycidyl group, a carboxyl group, and an oxazoline group, and a silane coupling agent. As these crosslinking agents, only one type may be used, or two or more types may be used in combination.

The chemical conversion treatment may be performed by only one type of chemical conversion treatment, or may be performed by combining two or more types of chemical conversion treatment. Furthermore, these chemical conversion treatments may be carried out using one kind of compound alone, or may be carried out using a combination of two or more kinds of compounds. Among the chemical conversion treatments, chromic acid chromate treatment, chromate treatment combining a chromic acid compound, a phosphoric acid compound, and an aminated phenol polymer are preferable.

In the chemical conversion treatment, the amount of the acid-resistant film formed on the surface of the barrier layer is not particularly limited. For example, in the case of performing the chromate treatment, a chromic acid compound per 1 m ² of the surface of the barrier layer. Is preferably about 0.5 to about 50 mg, more preferably about 1.0 to about 40 mg in terms of chromium, and the phosphorus compound is preferably about 0.5 to about 50 mg, more preferably about 1.0 to about 50 mg in terms of phosphorus. 40 mg and the aminated phenol polymer is preferably contained in a proportion of about 1 to about 200 mg, more preferably about 5.0 to 150 mg.

In the chemical conversion treatment, a solution containing a compound used for forming an acid-resistant film is applied to the surface of the barrier layer by a bar coating method, a roll coating method, a gravure coating method, a dipping method, or the like. The heating is performed so that the temperature is about 70 ° C. to 200 ° C. Further, before the chemical conversion treatment is performed on the barrier layer, the barrier layer may be previously subjected to a degreasing treatment by an alkali dipping method, an electrolytic cleaning method, an acid cleaning method, an electrolytic acid cleaning method, or the like. By performing the degreasing treatment in this way, it is possible to more efficiently perform the chemical conversion treatment on the surface of the barrier layer.

[Heat-fusion resin layer]
In the battery exterior material of the present invention, the heat-fusible resin layer corresponds to the innermost layer, and is a layer that heat-welds the heat-fusible resin layers together to seal the battery element when the battery is assembled.

The resin component used in the heat-fusible resin layer is not particularly limited as long as it can be heat-welded, and examples thereof include polyolefin, cyclic polyolefin, carboxylic acid-modified polyolefin, and carboxylic acid-modified cyclic polyolefin. .

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

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

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

Among the resin components used in the heat-fusible resin layer, carboxylic acid-modified polyolefin is preferable; carboxylic acid-modified polypropylene is more preferable.

The heat-fusible resin layer may be formed of one kind of resin component alone or may be formed of a blend polymer in which two or more kinds of resin components are combined. Furthermore, the heat-fusible resin layer may be formed of only one layer, but may be formed of two or more layers using the same or different resin components.

Further, the thickness of the heat-fusible resin layer is not particularly limited as long as it functions as the heat-fusible resin layer. For example, the thickness is about 10 to 100 μm, preferably about 15 to 50 μm.

[Adhesive layer]
In the battery exterior material of the present invention, an adhesive layer may be provided between the barrier layer and the heat-fusible resin layer as necessary, in order to firmly bond the barrier layer and the heat-fusible resin layer.

The adhesive layer is formed of an adhesive capable of adhering the barrier layer and the heat-fusible resin layer. About the adhesive agent used for formation of the said adhesive layer, the adhesion mechanism, the kind of adhesive component, etc. are the same as that of the case of the adhesive layer mentioned above. The adhesive component used in the adhesive layer is preferably a polyolefin resin, more preferably a carboxylic acid-modified polyolefin, and particularly preferably a carboxylic acid-modified polypropylene.

The thickness of the adhesive layer is not particularly limited as long as it exhibits the function as the adhesive layer, and it is, for example, about 2 to 50 μm, preferably about 15 to 30 μm.

[Method for Producing Battery Exterior Material of the Present Invention]
The method for producing the battery outer packaging material of the present invention is not particularly limited as long as a laminate in which layers having a predetermined composition are laminated is obtained. For example, the following method is exemplified.

First, a laminate in which the base material layer 12, the adhesive layer 13, and the barrier layer 14 shown in FIG. 1 are laminated in order (hereinafter, may be referred to as “laminate A”) is formed. Specifically, the laminate A is formed by, for example, extruding an adhesive used for forming the adhesive layer 13 on the base layer 12 or the barrier layer 14 whose surface is subjected to chemical conversion treatment as necessary. After applying and drying by a coating method such as a gravure coating method or a roll coating method, the barrier layer 14 or the base material layer 12 may be laminated to dry the adhesive layer 13.

Next, the heat-fusible resin layer 15 is laminated on the barrier layer 14 of the laminate A. When the heat-fusible resin layer 15 is directly laminated on the barrier layer 14, the resin component constituting the heat-fusible resin layer 15 is applied to the barrier layer 14 of the laminate A by a gravure coating method or a roll coating method. What is necessary is just to apply | coat by methods, such as. Further, when an adhesive layer (not shown) is provided between the barrier layer 14 and the heat-fusible resin layer 15, for example, (1) the adhesive layer and the heat-sealing layer on the barrier layer 14 of the laminate A (2) Separately, a laminate in which the adhesive layer and the heat-fusible resin layer 15 are laminated is formed, and this is formed into the laminate A. A method of laminating on the barrier layer 14 by a thermal laminating method. (3) An adhesive for forming an adhesive layer (not shown) on the barrier layer 14 of the laminate A is dried at a high temperature by extrusion or solution coating. Further, a method of laminating by heat laminating method, and laminating the heat-fusible resin layer 15 previously formed into a sheet shape on this adhesive layer by a thermal laminating method, (4) the barrier layer 14 of the laminate A, Heat fusion formed into a sheet Between the resin layer 15, while pouring an adhesive layer is melted, a method of bonding a laminate A and the heat-welding resin layer 15 via an adhesive layer (sandwich lamination method).

Next, the surface protective layer 11 is laminated on the surface of the base material layer 12 opposite to the barrier layer 14.
The surface protective layer 11 can be formed, for example, by applying the above-described resin composition for forming the surface protective layer 11 to the surface of the base material layer 12 and curing it by heating. The order of the step of laminating the barrier layer 14 on the surface of the base material layer 12 and the step of laminating the surface protective layer 11 on the surface of the base material layer 2 are not particularly limited. For example, after forming the surface protective layer 11 on the surface of the base material layer 2, the barrier layer 14 may be formed on the surface of the base material layer 2 opposite to the surface protective layer 11.

Surface protective layer 11 / base material layer 12 / adhesive layer 13 / barrier layer 14 whose surface is subjected to chemical conversion treatment as necessary / adhesive layer / heat-sealable resin layer provided as necessary In order to strengthen the adhesiveness of the adhesive layer 13 and the adhesive layer provided as necessary, a hot roll contact type, a hot air type, a near or far infrared type, etc. You may use for the heat processing of. An example of such heat treatment conditions is 150 to 250 ° C. for 1 to 5 minutes.

In the battery exterior material of the present invention, each layer constituting the laminate improves or stabilizes film forming properties, lamination processing, suitability for final processing of secondary products (pouching, embossing), and the like as necessary. Therefore, surface activation treatment such as corona treatment, blast treatment, oxidation treatment, ozone treatment may be performed.

[Applications for battery exterior materials]
The battery packaging material of the present invention is used as a packaging material for sealing and housing battery elements such as a positive electrode, a negative electrode, and an electrolyte.
Specifically, a battery element including at least a positive electrode, a negative electrode, and an electrolyte is formed in a state where the metal terminal connected to each of the positive electrode and the negative electrode protrudes to the outside with the battery packaging material of the present invention. By covering the periphery of the element so that a flange portion (region where the heat-fusible resin layers are in contact with each other) can be formed, and heat-sealing and sealing the heat-fusible resin layers of the flange portion, the battery A battery using the outer packaging material is provided. In addition, when accommodating a battery element using the battery outer packaging material of the present invention, the heat-fusible resin layer portion of the battery packaging material of the present invention is on the inner side (surface in contact with the battery element). Used.
A battery in which a battery element including at least a positive electrode, a negative electrode, and an electrolyte is housed in a package including a heat seal portion formed of a battery exterior material, and the JIS of the heat seal portion of the package A battery in which the difference between the specular gloss according to Z 8741 (1997) and the specular gloss according to JIS Z 8741 (1997) of the non-heat-sealed portion of the package is less than 1.8, This is one aspect of the present invention.
In addition, since the battery of this invention is performing cold forming, the battery exterior material is usually stretched. Since the density of the surface unevenness is reduced in the stretched portion in this way, the specular gloss after the battery molding is increased, and the amount of the specular gloss change of the battery exterior material according to the present invention is suppressed. There is a tendency.

The battery packaging material of the present invention may be used for either a primary battery or a secondary battery, but is preferably a secondary battery. The type of secondary battery to which the battery exterior material of the present invention is applied is not particularly limited. For example, a lithium ion battery, a lithium ion polymer battery, a lead battery, a nickel / hydrogen battery, a nickel / cadmium battery , Nickel / iron livestock batteries, nickel / zinc livestock batteries, silver oxide / zinc livestock batteries, metal-air batteries, polyvalent cation batteries, capacitors, capacitors and the like. Among these secondary batteries, lithium ion batteries and lithium ion polymer batteries are suitable applications for the battery packaging material of the present invention.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples and comparative examples.
In the text, “part” or “%” is based on mass unless otherwise specified.

Example 1
Apply chemical conversion treatment to both sides of an aluminum foil (thickness 35 μm) as a barrier layer, and use a polyester adhesive to which carbon black is added on one chemical conversion treatment surface so that the thickness after drying is about 3 μm. An adhesive layer formed in this manner was provided, and a stretched nylon film (thickness: 15 μm) as a base material layer was bonded by a dry laminating method through the adhesive layer.
Next, on the other chemical conversion treatment surface of the aluminum foil as the barrier layer, a random layer composed of a random copolymer of propylene and ethylene, a block layer composed of a block copolymer of propylene and ethylene, and a random layer composed of a random copolymer of propylene and ethylene A polypropylene film (thickness of 30 μm) as a heat-fusible resin layer in which layers are laminated one after another via a two-component curable polyolefin adhesive (a mixture of an acid-modified polyolefin compound and an epoxy compound) Were laminated together to produce a laminate.
A resin composition (silica with an average particle size of 1.5 μm as filler, erucic acid amide, and an acrylate resin by a gravure coat on the base material layer side of the obtained laminate (filler of the surface protective layer after drying) (Silica) concentration 8.0% by mass) is coated to a thickness of about 3 μm after drying to form a surface protective layer, surface protective layer / stretched nylon film (base material layer) / polyester adhesive (adhesion) The battery outer packaging material according to Example 1 is composed of: (agent layer) / aluminum (barrier layer) / olefin adhesive (adhesive layer) / polypropylene film (heat-fusible resin layer) subjected to double-side chemical conversion treatment Obtained.
In the chemical conversion treatment, an aqueous solution composed of a phenol resin, a chromium fluoride compound, and phosphoric acid was used as a treatment solution, applied by a roll coating method, and baked under conditions where the film temperature was 180 ° C. or higher. The application amount of chromium was 10 mg / m ² (dry mass).

(Examples 2 to 5, Comparative Examples 1 and 2)
The filler (silica) concentration in the surface protective layer after drying was 7.6% by mass (Example 2), 6.0% by mass (Example 3), 3.8% by mass (Example 4), 0.8% by mass. % (Example 5), 8.4% by mass (Comparative Example 1), and 8.8% by mass (Comparative Example 2).

The following evaluation was performed about the battery exterior material obtained by the Example and the comparative example.
[Appearance change evaluation before and after heat sealing]
A battery exterior material sample cut out with a width of 60 mm and a length of 200 mm and turned back with a length of 100 mm so that the surface protective layer is on the outside was confirmed to change in appearance when heat sealed under the following conditions.
A heat sealer TP-701-B manufactured by Tester Sangyo Co., Ltd. was used as the heat sealer, and heat sealing was performed at a pressure of 1.0 MPa (sealing area 60 mm × 7 mm), a time of 6 seconds, and a temperature of 190 ° C. (1997), a difference (change amount) in specular gloss between the heat-sealed portion and the non-heat-sealed portion was measured. Specifically, the specular gloss before and after heat sealing was measured at an incident angle of 60 degrees using a gloss measuring instrument micro-tri-gloss (measurement area 9 mm × 15 mm) manufactured by Toyo Seiki Seisakusho. The results are shown in Table 1. The effective value is one decimal place.

[Evaluation of surface roughness]
The unevenness state before and after heat sealing of the battery exterior material sample produced in the same manner as the appearance change evaluation before and after heat sealing was confirmed by the following method.
The surface of the surface protective layer of the battery exterior material was photographed at a magnification of 150 times using a laser microscope VK-9710 manufactured by Keyence, and the arithmetic average using the image processing software VK Analyzer from Keyence Co. The roughness Ra was calculated. The analysis was performed by executing the “all areas” command for “surface roughness” after performing “surface inclination correction (automatic)”. The results are shown in Table 1.

As shown in Table 1, since the amount of change in the specular gloss before and after heat sealing was less than 1.8, the battery exterior materials according to the examples had no appearance defects. On the other hand, since the amount of change in the specular gloss before and after heat sealing was more than 1.8, the battery exterior material according to Comparative Example 1 had a poor appearance. Note that when the amount of change in specular gloss was 1.8 or more, it was determined that the appearance was poor because the amount of change in specular gloss before and after heat sealing was 0.5, 1.0, 1.5, 1 .8, 2.0 samples were prepared, and it was judged whether there was a change in appearance on 10 monitors. As a result, it was judged that 10 or more samples were changed in appearance, so that 1.8 or more samples were 1.8 or more. The thing was regarded as poor appearance.
In addition, the amount of change in the specular gloss before and after heat sealing, which was measured in the same manner as described above, for the battery using the battery case material according to the example was less than 1.8.

The battery packaging material of the present invention can be used very suitably for a battery packaging material that houses battery elements.

DESCRIPTION OF SYMBOLS 10 Battery exterior material 11 Surface protective layer 12 Base material layer 13 Adhesive layer 14 Barrier layer 15 Heat-fusible resin layer

Claims

In order from the outside, a battery exterior material comprising a surface protective layer, a base material layer, an adhesive layer, a barrier layer and a heat-fusible resin layer,
Conforms to JIS Z 8741 (1997) of the heat-sealed portion of the surface protective layer when heat-sealed at 190 ° C., 1.0 MPa, 6 seconds with the heat-fusible resin layers facing each other. The battery cladding | exterior_material whose difference of the specular glossiness and the specular glossiness based on JISZ8741 (1997) of the non-heat-sealing part of the said surface protective layer is less than 1.8.
2. The battery according to claim 1, wherein the surface protective layer has irregularities on a surface opposite to the substrate layer side, and when the arithmetic average roughness of the irregularities is Ra, the Ra satisfies the following formula. Exterior material.
0.20 μm ≦ Ra ≦ 0.50 μm
The battery exterior material according to claim 1, wherein the surface protective layer contains a filler.
The filler is selected from the group consisting of titanium oxide, silica, talc, clay, heavy calcium carbonate, light calcium carbonate, barium sulfate, calcium silicate, synthetic silicate, aluminum hydroxide, and fine silicate powder. The battery exterior material according to claim 3, which is an inorganic filler made of at least one of the above materials.
A battery in which a battery element including at least a positive electrode, a negative electrode, and an electrolyte is housed in a package including a heat seal portion formed of a battery exterior material,
There is a difference between the specular gloss according to JIS Z 8741 (1997) of the heat seal part of the package and the specular gloss according to JIS Z 8741 (1997) of the non-heat seal part of the package. A battery that is less than 1.8.