JP2016186871A - Battery packaging material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery packaging material excellent in ink printing characteristics on a base material layer-side surface.SOLUTION: A battery packaging material comprises a laminated body formed by sequentially stacking at least a base material layer 1, a metal layer 3, and a sealant layer 4, and has a contact angle with respect to water on a base material layer-side surface of 80° or less. Adhesive layers 3, 5 may be further stacked. A bar code, a character or the like can be formed by printing ink on at least a part of the base material layer-side surface. In order to control a contact angle, the base material layer-side surface is subjected to surface treatment such as corona discharge.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a battery packaging material excellent in ink printing characteristics on the surface of a base material layer.

  Conventionally, various types of batteries have been developed. In any battery, a packaging material is an indispensable member for sealing battery elements such as electrodes and electrolytes. Conventionally, metal packaging materials have been widely used as battery packaging, but in recent years, with the increasing performance of electric vehicles, hybrid electric vehicles, personal computers, cameras, mobile phones, etc., batteries are required to have various shapes. At the same time, there is a demand for reduction in thickness and weight. However, metal battery packaging materials that have been widely used in the past have the disadvantages that it is difficult to follow the diversification of shapes and that there is a limit to weight reduction.

  Therefore, a film-like laminate in which a base material layer / adhesive layer / metal layer / sealant layer are sequentially laminated is proposed as a battery packaging material that can be easily processed into various shapes and can be made thinner and lighter. (For example, refer to Patent Document 1). Such a film-shaped battery packaging material is formed so that the battery element can be sealed by causing the sealant layers to face each other and heat-sealing the peripheral portion by heat sealing.

  In various packaging materials formed by the laminates as described above, ink is printed on the surface of the base material layer side to form barcodes, patterns, characters, etc., on the printed side base material layer A method of printing on a packaging material by a method of laminating an adhesive and a metal foil (generally referred to as back printing) is widely adopted. However, when such a printing surface exists between the base material layer and the metal layer, the adhesion between the base material layer and the metal layer is lowered, and delamination is likely to occur between the layers. In particular, since high safety is required for a battery to which the battery packaging material is applied, such a method of printing by back-printing is avoided in the battery packaging material. Therefore, conventionally, when printing a barcode or the like on a battery packaging material, a method of sticking a seal on which a print is formed on the surface of the base material layer side is generally employed.

  However, when the seal on which the printing is formed is affixed to the surface on the base material layer side, the thickness and weight of the battery packaging material increase. Therefore, from the recent trend of further reduction in thickness and weight for battery packaging materials, a method of printing directly on the surface of the battery packaging material on the base layer side has been studied.

  Pad printing (also referred to as tampo printing) is known as a method for printing directly on the surface of the battery packaging material on the base material layer side by ink printing. Pad printing is a printing method as follows. First, ink is poured into a concave portion of a flat plate in which a pattern to be printed is etched. Next, the silicon pad is pressed from above the concave portion to transfer the ink to the silicon pad. Next, the ink transferred to the surface of the silicon pad is transferred to the object to be printed to form a print on the object to be printed. In such pad printing, the ink is transferred to the object to be printed using an elastic silicon pad or the like. Therefore, it is easy to print on the surface of the battery packaging material after molding, and the battery element is made of the battery packaging material. After sealing, the battery can be printed.

  By the way, in the battery packaging material, when the battery element is encapsulated, it is molded with a mold to form a space for accommodating the battery element. There is a problem that cracks and pinholes are likely to occur in the metal layer at the flange portion of the mold due to the battery packaging material being stretched during this molding. In order to solve such a problem, the surface of the base material layer of the battery packaging material is coated with a lubricant, or the lubricant bleed out on the surface of the sealant layer is transferred to the surface of the base material layer in a roll state. A method for improving the slipperiness of the base material layer is known. By adopting such a method, the battery packaging material is easily drawn into the mold during molding, and cracks and pinholes in the battery packaging material can be suppressed. In particular, in order to reduce the thickness and weight of battery packaging materials in recent years, it is desirable to increase the slipperiness of the battery packaging material by making a lubricant present on the surface of the battery packaging material on the base layer side.

JP 2008-287971 A

However, when the present inventors examined, when a lubricant was present on the surface of the base material layer side to improve the moldability of the battery packaging material, ink was repelled on the surface of the base material layer side. It has become clear that the ink is difficult to fix, and there is a case where a missing portion where the ink is not formed may occur. In particular, it has been clarified that printability tends to be insufficient when printing is performed by pad printing.
Under such circumstances, the main object of the present invention is to provide a battery packaging material having excellent ink printing characteristics on the surface of the base material layer. Furthermore, this invention also aims at providing the manufacturing method of the said packaging material for batteries, and the battery using the said packaging material for batteries.

  The present inventors have intensively studied to solve the above problems. As a result, in the battery packaging material comprising a laminate in which at least the base material layer, the metal layer, and the sealant layer are sequentially laminated, the surface of the base material layer side (the surface opposite to the sealant layer) contacts. It has been found that by setting the angle to 80 ° or less, the printing characteristics of the ink on the surface on the base material layer side can be effectively improved. Furthermore, the present inventors have found that the contact angle of the surface on the base material layer side can be set to 80 ° or less by performing corona treatment on the surface on the base material layer side. The present invention has been completed by further studies based on these findings.

That is, this invention provides the invention of the aspect hung up below.
Item 1. It consists of a laminate in which at least a base material layer, a metal layer, and a sealant layer are sequentially laminated,
A battery packaging material having a contact angle of a surface on the base material layer side of 80 ° or less.
Item 2. Item 2. The battery packaging material according to Item 1, wherein the battery packaging material is used by printing ink on at least a part of the surface on the substrate layer side.
Item 3. Item 3. The battery packaging material according to Item 1 or 2, wherein ink is printed on at least a part of the surface of the substrate layer side.
Item 4. Item 4. The battery packaging material according to any one of Items 1 to 3, wherein the substrate layer side surface is subjected to corona treatment.
Item 5. Item 5. The battery packaging material according to any one of Items 1 to 4, wherein an adhesive layer is laminated between the base material layer and the metal layer.
Item 6. Item 6. The battery packaging material according to any one of Items 1 to 5, wherein an adhesive layer is laminated between the metal layer and the sealant layer.
Item 7. Item 7. The battery packaging material according to any one of Items 1 to 6, wherein the metal layer is formed of an aluminum foil.
Item 8. Item 8. The battery packaging material according to any one of Items 1 to 7, wherein a lubricant is present on the surface of the base material layer.
Item 9. Item 9. A battery in which a battery element including at least a positive electrode, a negative electrode, and an electrolyte is accommodated in the battery packaging material according to any one of Items 1 to 8.
Item 10. A laminating step of obtaining a laminate by laminating at least a base material layer, a metal layer, and a sealant layer;
Applying a corona treatment to the surface of the base material layer side so that the contact angle of the surface of the base material layer side is 80 ° or less; and
A method for producing a battery packaging material.
Item 11. Item 11. The method for producing a battery packaging material according to Item 10, comprising a step of printing ink on at least a part of the surface on the base material layer side after the corona treatment step.

  ADVANTAGE OF THE INVENTION According to this invention, the packaging material for batteries excellent in the printing characteristic of the ink in the surface at the side of a base material layer can be provided. Furthermore, according to this invention, the manufacturing method of the battery using the said packaging material for batteries and the said packaging material for batteries can also be provided.

It is a figure which shows an example of the cross-section of the packaging material for batteries of this invention. It is a figure which shows an example of the cross-section of the packaging material for batteries of this invention. It is a figure which shows an example of the cross-section of the packaging material for batteries of this invention.

  The battery packaging material of the present invention comprises a laminate in which at least a base material layer, a metal layer, and a sealant layer are sequentially laminated, and the contact angle of the surface on the base material layer side is 80 ° or less. It is characterized by. Hereinafter, the battery packaging material of the present invention, the method for producing the battery packaging material, and the battery using the battery packaging material will be described in detail.

1. Laminated Structure of Battery Packaging Material As shown in FIG. 1, the battery packaging material of the present invention comprises a laminate in which at least a base material layer 1, a metal layer 3, and a sealant layer 4 are sequentially laminated. In the battery packaging material of the present invention, the base material layer 1 is the outermost layer (when the coating layer 6 is provided, the coating layer 6 is the outermost layer), and the sealant layer 4 is the innermost layer. That is, when the battery is assembled, the sealant layers 4 positioned at the periphery of the battery element are thermally welded to seal the battery element, thereby sealing the battery element.

  As shown in FIG. 1, the battery packaging material of the present invention is provided with an adhesive layer 2 between the base material layer 1 and the metal layer 3 as necessary for the purpose of enhancing the adhesion. Also good. In addition, as shown in FIG. 2, an adhesive layer 5 may be provided between the metal layer 3 and the sealant layer 4 as necessary for the purpose of improving the adhesion. Further, as shown in FIG. 3, a coating layer 6 may be provided on the surface of the base material layer 1 (surface opposite to the metal layer 3 side).

2. Composition of each layer forming base material for battery [base material layer 1]
In the battery packaging material of the present invention, the base material layer 1 is a layer located in the outermost layer. However, when it has the coating layer 6, the coating layer 6 is located in the outermost layer.

  The material for forming the base material layer 1 is not particularly limited as long as it has insulating properties. Examples of the material for forming the base material layer 1 include polyester, polyamide, epoxy resin, acrylic resin, fluorine resin, polyurethane, silicon resin, phenol resin, polyetherimide, polyimide, and a mixture or copolymer thereof. Can be mentioned.

  Specific examples of the polyester include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, polycarbonate, copolymerized polyester mainly composed of ethylene terephthalate, butylene terephthalate as a repeating unit. Examples thereof include a copolymer polyester mainly used. The copolymer polyester mainly composed of ethylene terephthalate is a copolymer polyester that polymerizes with ethylene isophthalate mainly composed of ethylene terephthalate (hereinafter, polyethylene (terephthalate / isophthalate)). Abbreviated), polyethylene (terephthalate / isophthalate), polyethylene (terephthalate / adipate), polyethylene (terephthalate / sodium sulfoisophthalate), polyethylene (terephthalate / sodium isophthalate), polyethylene (terephthalate / phenyl-dicarboxylate) And polyethylene (terephthalate / decanedicarboxylate). In addition, as a copolymer polyester mainly composed of butylene terephthalate as a repeating unit, specifically, a copolymer polyester that polymerizes with butylene isophthalate having butylene terephthalate as a repeating unit (hereinafter referred to as polybutylene (terephthalate / isophthalate)). For example), polybutylene (terephthalate / adipate), polybutylene (terephthalate / sebacate), polybutylene (terephthalate / decanedicarboxylate), polybutylene naphthalate and the like. These polyesters may be used individually by 1 type, and may be used in combination of 2 or more type. Polyester has the advantage of being excellent in electrolytic solution resistance and less likely to cause whitening due to the adhesion of the electrolytic solution, and is suitably used as a material for forming the base material layer 1.

  Specific examples of polyamides include aliphatic polyamides such as nylon 6, nylon 66, nylon 610, nylon 12, nylon 46, and copolymers of nylon 6 and nylon 6,6; terephthalic acid and / or Nylon 6I, Nylon 6T, Nylon 6IT, Nylon 6I6T (I represents isophthalic acid, T represents terephthalic acid) and the like, which include a structural unit derived from isophthalic acid, Aromatic polyamides such as silylene adipamide (MXD6); alicyclic polyamides such as polyaminomethylcyclohexyl adipamide (PACM6); and lactam components and isocyanate components such as 4,4′-diphenylmethane-diisocyanate. Polymerized polyamide, co-weight Polyester amide copolymer and polyether ester amide copolymer is a copolymer of polyamide and polyester and polyalkylene ether glycol; copolymers thereof, and the like. These polyamides may be used individually by 1 type, and may be used in combination of 2 or more type. The stretched polyamide film is excellent in stretchability, can prevent whitening due to resin cracking of the base material layer 1 during molding, and is suitably used as a material for forming the base material layer 1.

  The base material layer 1 may be formed of a uniaxially or biaxially stretched resin film, or may be formed of an unstretched resin film. Among them, a uniaxially or biaxially stretched resin film, in particular, a biaxially stretched resin film has improved heat resistance by orientation crystallization, and thus is suitably used as the base material layer 1. Moreover, the base material layer 1 may be formed by coating the above-mentioned raw material on the metal layer 3.

  Among these, as a resin film which forms the base material layer 1, Preferably nylon and polyester, More preferably, biaxially stretched nylon, biaxially stretched polyester, Most preferably, biaxially stretched nylon is mentioned.

  The base material layer 1 can also be laminated with at least one of resin films and coatings of different materials in order to improve pinhole resistance and insulation when used as a battery package. Specific examples include a multilayer structure in which a polyester film and a nylon film are laminated, and a multilayer structure in which a biaxially stretched polyester and a biaxially stretched nylon are laminated. When making the base material layer 1 into a multilayer structure, each resin film may be adhere | attached through an adhesive agent, and may be laminated | stacked directly without an adhesive agent. In the case of bonding without using an adhesive, for example, a method of bonding in a hot melt state such as a co-extrusion method, a sand lamination method, or a thermal laminating method can be mentioned. Moreover, when making it adhere | attach through an adhesive agent, the adhesive agent to be used may be a two-component curable adhesive, or a one-component curable adhesive. Further, the bonding mechanism of the adhesive is not particularly limited, and may be any of a chemical reaction type, a solvent volatilization type, a heat melting type, a hot pressure type, an electron beam curing type such as UV and EB, and the like. As an adhesive component, polyester resin, polyether resin, polyurethane resin, epoxy resin, phenol resin resin, polyamide resin, polyolefin resin, polyvinyl acetate resin, cellulose resin, (meth) acrylic resin Resins, polyimide resins, amino resins, rubbers, and silicon resins can be used.

  In the present invention, from the viewpoint of improving the moldability of the battery packaging material, it is preferable that a lubricant adheres to the surface of the base material layer 1 side. Although it does not restrict | limit especially as a lubricant, Preferably an amide type lubricant is mentioned. Specific examples of the amide-based lubricant include saturated fatty acid amide, unsaturated fatty acid amide, substituted amide, methylolamide, saturated fatty acid bisamide, unsaturated fatty acid bisamide, and the like. Specific examples of the saturated fatty acid amide include lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, hydroxy stearic acid amide and the like. Specific examples of the unsaturated fatty acid amide include oleic acid amide and erucic acid amide. Specific examples of the substituted amide include N-oleyl palmitate, N-stearyl stearate, N-stearyl oleate, N-oleyl stearate, N-stearyl erucamide, and the like. Specific examples of methylolamide include methylol stearamide. Specific examples of saturated fatty acid bisamides include methylene bis stearamide, ethylene biscapric amide, ethylene bis lauric acid amide, ethylene bis stearic acid amide, ethylene bishydroxy stearic acid amide, ethylene bisbehenic acid amide, hexamethylene bis stearic acid amide. Examples include acid amide, hexamethylene bisbehenic acid amide, hexamethylene hydroxystearic acid amide, N, N′-distearyl adipic acid amide, N, N′-distearyl sebacic acid amide, and the like. Specific examples of unsaturated fatty acid bisamides include ethylene bisoleic acid amide, ethylene biserucic acid amide, hexamethylene bisoleic acid amide, N, N′-dioleyl adipic acid amide, N, N′-dioleyl sebacic acid amide Etc. Specific examples of the fatty acid ester amide include stearoamidoethyl stearate. Specific examples of the aromatic bisamide include m-xylylene bis stearic acid amide, m-xylylene bishydroxy stearic acid amide, N, N′-cysteallyl isophthalic acid amide and the like. One type of lubricant may be used alone, or two or more types may be used in combination.

  As thickness of the base material layer 1, about 10-50 micrometers, for example, Preferably about 15-30 micrometers is mentioned.

  The battery packaging material of the present invention is characterized in that the contact angle of the surface on the base material layer 1 side (the outermost surface of the battery packaging material) is 80 ° or less. That is, when the base material layer 1 constitutes the outermost surface, the contact angle of the surface of the base material layer 1 is 80 ° or less. Moreover, when providing the below-mentioned coating layer 6 in the outer side of the base material layer 1, the contact angle of the surface of the coating layer 6 will be 80 degrees or less. In the present invention, when the contact angle of the surface of the battery packaging material on the base material layer 1 side is 80 ° or less, the ink is hardly repelled on the surface of the base material layer 1 side, and the printability is excellent. In particular, when ink is printed by pad printing on a battery packaging material that has improved formability by making a lubricant present on the surface of the base material layer 1, the ink is repelled and printed on the surface of the base material layer 1 side. In such a case, the battery packaging material of the present invention has a contact angle of the surface on the base material layer 1 side of 80 ° or less, so that the ink is not easily repelled and the pad It is particularly suitable as a battery packaging material in which printing is formed on the surface of the base material layer by printing.

  In the battery packaging material of the present invention, the contact angle of the surface on the base material layer 1 side is not particularly limited as long as it is 80 ° or less, but from the viewpoint of improving printability, it is preferably 79 ° or less. Preferably about 72 degrees or less is mentioned.

  In the present invention, the contact angle of the battery packaging material is a value measured using LSE-A210 manufactured by Nick Co., Ltd., and the specific method is as described in the examples.

  In the battery packaging material of the present invention, the contact angle of the surface on the base material layer 1 side can be suitably adjusted to 80 ° or less, for example, by subjecting the surface on the base material layer 1 side to corona treatment. Corona treatment can be performed by irradiating the surface on the base material layer 1 side with corona discharge using a commercially available corona surface treatment apparatus. The condition of the corona treatment is not particularly limited as long as the contact angle of the surface on the base material layer 1 side is 80 ° or less. For example, the contact angle can be reduced to 80 ° or less by treating the surface of the base material layer 1 at an irradiation output of 1 Kw or more at a speed of 10 MT / min.

  In the battery packaging material of the present invention, ink can be suitably printed on at least part of the surface of the base material layer 1 side. That is, in the present invention, the battery packaging material in which ink is printed on the surface of the base material layer 1 side exposes the ink (cured ink, dried product, etc.) printed on the surface of the base material layer 1 side. ing. The printed ink can form, for example, printing of barcodes, patterns, characters, and the like. The ink used for printing is not particularly limited, and a known ink can be used. For example, a photocurable ink that is cured by irradiation with ultraviolet rays or the like, an inkjet ink that is used in an inkjet printer, or the like. Can be used.

[Adhesive layer 2]
In the battery packaging material of the present invention, the adhesive layer 2 is a layer provided as necessary in order to adhere the base material layer 1 and the metal layer 3.

  The adhesive layer 2 is formed of an adhesive capable of adhering the base material layer 1 and the metal layer 3. The adhesive used for forming the adhesive layer 2 may be a two-component curable adhesive or a one-component curable adhesive. Furthermore, the adhesive mechanism of the adhesive used for forming the adhesive layer 2 is not particularly limited, and may be any of a chemical reaction type, a solvent volatilization type, a heat melting type, a hot pressure type, and the like.

  Specific examples of the resin component of the adhesive that can be used to form the adhesive layer 2 include polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, polycarbonate, and copolyester. Resin; Polyether adhesive; Polyurethane adhesive; Epoxy resin; Phenol resin resin; Polyamide resin such as nylon 6, nylon 66, nylon 12, copolymer polyamide; polyolefin, acid-modified polyolefin, metal-modified polyolefin, etc. Polyolefin resin; polyvinyl acetate resin; cellulose adhesive; (meth) acrylic resin; polyimide resin; urea resin, melamine resin and other amino resins; chloroprene rubber, nitrile rubber, styrene - rubbers such as butadiene rubber, silicone resin; fluorinated ethylene propylene copolymer, and the like. These adhesive components may be used individually by 1 type, and may be used in combination of 2 or more type. The combination mode of two or more kinds of adhesive components is not particularly limited. For example, as the adhesive component, a mixed resin of polyamide and acid-modified polyolefin, a mixed resin of polyamide and metal-modified polyolefin, polyamide and polyester, Examples thereof include a mixed resin of polyester and acid-modified polyolefin, and a mixed resin of polyester and metal-modified polyolefin. Among these, extensibility, durability under high-humidity conditions, anti-hypertensive action, thermal deterioration-preventing action during heat sealing, etc. are excellent, and a decrease in lamination strength between the base material layer 1 and the metal layer 3 is suppressed. From the viewpoint of effectively suppressing the occurrence of delamination, a polyurethane two-component curable adhesive; polyamide, polyester, or a blended resin of these with a modified polyolefin is preferable.

  The adhesive layer 2 may be multilayered with different adhesive components. When the adhesive layer 2 is multilayered with different adhesive components, from the viewpoint of improving the lamination strength between the base material layer 1 and the metal layer 3, the adhesive component disposed on the base material layer 1 side is used as the base material layer 1. It is preferable to select a resin having excellent adhesion to the metal layer 3 and to select an adhesive component having excellent adhesion to the metal layer 3 as the adhesive component disposed on the metal layer 3 side. When the adhesive layer 2 is multilayered with different adhesive components, specifically, the adhesive component disposed on the metal layer 3 side is preferably an acid-modified polyolefin, a metal-modified polyolefin, a polyester and an acid-modified polyolefin. And a resin containing a copolyester.

  About the thickness of the contact bonding layer 2, about 2-50 micrometers, for example, Preferably about 3-25 micrometers is mentioned.

[Metal layer 3]
In the battery packaging material of the present invention, the metal layer 3 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 packaging material. Specific examples of the metal forming the metal layer 3 include metal foils such as aluminum, stainless steel, and titanium. Among these, aluminum is preferably used. In order to prevent wrinkles and pinholes during the production of the packaging material, soft aluminum such as annealed aluminum (JIS A8021P-O) or (JIS A8079P-O) is used as the metal layer 3 in the present invention. Is preferred.

  About the thickness of the metal layer 3, about 10-200 micrometers is preferable, for example, Preferably it is about 20-100 micrometers.

  Further, the metal layer 3 is preferably subjected to chemical conversion treatment on at least one surface, preferably at least the surface on the sealant layer 4 side, and more preferably both surfaces, for the purpose of stabilizing adhesion, preventing dissolution and corrosion, and the like. . Here, the chemical conversion treatment is a treatment for forming an acid-resistant film on the surface of the metal layer 3. Chemical conversion treatment is, for example, chromate chromate treatment using a chromic acid compound such as chromium nitrate, chromium fluoride, chromium sulfate, chromium acetate, chromium oxalate, chromium biphosphate, chromic acetyl acetate, chromium chloride, potassium sulfate chromium, etc. ; Phosphoric acid chromate treatment using phosphoric acid compounds such as sodium phosphate, potassium phosphate, ammonium phosphate, polyphosphoric acid; aminated phenol heavy consisting of repeating units represented by the following general formulas (1) to (4) Examples thereof include chromate treatment using a coalescence. In the aminated phenol polymer, the repeating units represented by the following general formulas (1) to (4) may be included singly or in any combination of two or more. Also good.

In 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 represent 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, C1-C4 linear or branched alkyl groups, such as a tert- butyl group, are mentioned. 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- A linear or branched chain having 1 to 4 carbon atoms substituted with one hydroxy group such as hydroxypropyl group, 1-hydroxybutyl group, 2-hydroxybutyl group, 3-hydroxybutyl group, 4-hydroxybutyl group An alkyl group is mentioned. In the general formulas (1) to (4), X is preferably any one of a hydrogen atom, a hydroxyl group, and a droxyalkyl group. The number average molecular weight of the aminated phenol polymer composed of the repeating units represented by the general formulas (1) to (4) is, for example, about 500 to about 1,000,000, preferably about 1000 to about 20,000.

  In addition, as a chemical conversion treatment method for imparting corrosion resistance to the metal layer 3, a metal oxide such as aluminum oxide, titanium oxide, cerium oxide, tin oxide, or barium sulfate fine particles dispersed in phosphoric acid is coated. A method of forming a corrosion-resistant treatment layer on the surface of the metal layer 3 by performing a baking treatment at 150 ° C. or higher can be mentioned. Moreover, you may form the resin layer which crosslinked the cationic polymer with the crosslinking agent on the corrosion-resistant process layer. Here, as the cationic polymer, for example, polyethyleneimine, an ionic polymer complex composed of a polymer having polyethyleneimine and a carboxylic acid, a primary amine-grafted acrylic resin in which a primary amine is grafted on an acrylic main skeleton, polyallylamine, or Examples thereof include aminophenols and derivatives thereof. These cationic polymers may be used individually by 1 type, and may be used in combination of 2 or more type. Examples of the crosslinking agent include compounds having at least one functional group selected from the group consisting of isocyanate groups, glycidyl groups, carboxyl groups, and oxazoline groups, silane coupling agents, and the like. These crosslinking agents may be used alone or in combination of two or more.

  These chemical conversion treatments may be performed alone or in combination of two or more chemical conversion treatments. 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 these, chromic acid chromate treatment is preferable, and chromate treatment in which a chromic acid compound, a phosphoric acid compound, and an aminated phenol polymer are combined is more preferable.

The amount of the acid-resistant film formed on the surface of the metal layer 3 in the chemical conversion treatment is not particularly limited. For example, if the chromate treatment is performed by combining a chromic acid compound, a phosphoric acid compound, and an aminated phenol polymer. The chromic acid compound is about 0.5 to about 50 mg, preferably about 1.0 to about 40 mg in terms of chromium, and the phosphorus compound is about 0.5 to about 50 mg in terms of phosphorus per 1 m ² of the surface of the metal layer 3. Is preferably about 1.0 to about 40 mg, and about 1 to about 200 mg, preferably about 5.0 to 150 mg of aminated phenol polymer.

  In the chemical conversion treatment, a solution containing a compound used for forming an acid-resistant film is applied to the surface of the metal layer 3 by a bar coating method, a roll coating method, a gravure coating method, a dipping method or the like, and then the temperature of the metal layer 3 is reached. Is performed by heating so as to be about 70 to 200 ° C. In addition, before the chemical conversion treatment is performed on the metal layer 3, the metal layer 3 may be 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 in advance. By performing the degreasing treatment in this way, it becomes possible to more efficiently perform the chemical conversion treatment on the surface of the metal layer 3.

[Sealant layer 4]
In the battery packaging material of the present invention, the sealant layer 4 corresponds to the innermost layer, and is a layer that seals the battery element by heat-sealing the sealant layers when the battery is assembled.

  The resin component used for the sealant layer 4 is not particularly limited as long as it can be thermally 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 (for example, 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, and 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. 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 obtained by modifying the polyolefin by block polymerization or graft polymerization 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 α, β with respect to the cyclic polyolefin. -A polymer obtained by block polymerization or graft polymerization of an unsaturated carboxylic acid or its anhydride. The cyclic polyolefin to be modified with carboxylic acid is the same as described above. The carboxylic acid used for modification is the same as that used for modification of the acid-modified cycloolefin copolymer.

  Among these resin components, carboxylic acid-modified polyolefin is preferable; carboxylic acid-modified polypropylene is more preferable.

  The sealant layer 4 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 sealant layer 4 may be formed of only one layer, but may be formed of two or more layers using the same or different resin components.

  In the battery packaging material of the present invention, the sealant layer 4 may contain a lubricant. The type of lubricant is not particularly limited, and examples thereof include those exemplified in the above item [Base Material Layer 1]. When the sealant layer 4 contains a lubricant, the content thereof may be selected as appropriate, but preferably about 700 to 1200 ppm, more preferably about 800 to 1100 ppm. In the present invention, the content of the lubricant in the sealant layer 4 is the total amount of the lubricant present in the sealant layer 4 and the lubricant present on the surface of the sealant layer 4.

  The thickness of the sealant layer 4 can be selected as appropriate, and is about 10 to 100 μm, preferably about 15 to 50 μm.

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

  The adhesive layer 5 is formed of an adhesive capable of bonding the metal layer 3 and the sealant layer 4. With respect to the adhesive used for forming the adhesive layer 5, the adhesive mechanism, the types of adhesive components, and the like are the same as those of the adhesive layer 2. The adhesive component used for the adhesive layer 5 is preferably a polyolefin resin, more preferably a carboxylic acid-modified polyolefin, particularly preferably a carboxylic acid-modified polypropylene.

  About the thickness of the contact bonding layer 5, 2-50 micrometers, for example, Preferably 15-30 micrometers is mentioned.

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

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

  Examples of the matting agent include fine particles having a particle size of about 0.5 nm to 5 μm. The material of the matting agent is not particularly limited, and examples thereof include metals, metal oxides, inorganic substances, and organic substances. The shape of the matting agent is not particularly limited, and examples thereof include a spherical shape, a fiber shape, a plate shape, an indeterminate shape, and a balloon shape. Specific examples of the matting agent include talc, silica, graphite, kaolin, montmorilloid, montmorillonite, synthetic mica, hydrotalcite, silica gel, zeolite, aluminum hydroxide, magnesium hydroxide, zinc oxide, magnesium oxide, and aluminum oxide. , Neodymium oxide, antimony oxide, titanium oxide, cerium oxide, calcium sulfate, barium sulfate, calcium carbonate, calcium silicate, lithium carbonate, calcium benzoate, calcium oxalate, magnesium stearate, alumina, carbon black, carbon nanotubes, High melting point nylon, crosslinked acrylic, crosslinked styrene, crosslinked polyethylene, benzoguanamine, gold, aluminum, copper, nickel and the like can be mentioned. These matting agents may be used individually by 1 type, and may be used in combination of 2 or more type. Among these matting agents, silica, barium sulfate, and titanium oxide are preferable from the viewpoint of dispersion stability and cost. The matting agent may be subjected to various surface treatments such as insulation treatment and high dispersibility treatment on the surface.

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

  The thickness of the coating layer 6 is not particularly limited as long as the above function as the coating layer 6 is exhibited. For example, the thickness is about 0.5 to 10 μm, preferably about 1 to 5 μm.

3. Method for Producing Battery Packaging Material The method for producing the battery 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 1, the adhesive layer 2, and the metal layer 3 are laminated in order (hereinafter also referred to as “laminate A”) is formed. Specifically, the laminate A is formed by applying an adhesive used for forming the adhesive layer 2 on the base material layer 1 or the metal layer 3 whose surface is subjected to chemical conversion treatment, if necessary, using a gravure coating method, a roll After applying and drying by a coating method such as a coating method, it can be performed by a dry lamination method in which the metal layer 3 or the substrate layer 1 is laminated and the adhesive layer 2 is cured.

  Next, the sealant layer 4 is laminated on the metal layer 3 of the laminate A. When the sealant layer 4 is directly laminated on the metal layer 3, the resin component constituting the sealant layer 4 may be applied on the metal layer 3 of the laminate A by a method such as a gravure coating method or a roll coating method. . In the case where the adhesive layer 5 is provided between the metal layer 3 and the sealant layer 4, for example, (1) the adhesive layer 5 and the sealant layer 4 are laminated on the metal layer 3 of the laminate A by coextrusion. (2) A method of separately forming a laminate in which the adhesive layer 5 and the sealant layer 4 are laminated, and laminating the laminate on the metal layer 3 of the laminate A by a thermal lamination method, 3) An adhesive for forming the adhesive layer 5 is laminated on the metal layer 3 of the laminate A by an extrusion method or a solution-coated high temperature drying and baking method, and a sheet-like shape is formed on the adhesive layer 5 in advance. (4) A melted adhesive layer 5 is placed between the metal layer 3 of the laminate A and the sealant layer 4 previously formed into a sheet shape. Adhesive layer 5 while pouring Method (sand lamination method) and the like to bond the laminate A and the sealant layer 4. In addition, in order to strengthen the adhesiveness of the adhesive layer 2 and the adhesive layer 5 provided as necessary, it may be further subjected to a heat treatment such as a hot roll contact type, a hot air type, a near or far infrared type. Examples of such heat treatment conditions include 150 to 250 ° C. for 1 to 5 minutes.

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

  Furthermore, in the method for producing a battery packaging material of the present invention, a corona treatment step is performed in which the surface of the base material layer 1 is subjected to corona treatment so that the contact angle of the surface on the base material layer 1 side is 80 ° or less. The corona treatment is as described above.

  Moreover, when printing ink on the surface of the packaging material for batteries, the process of printing ink on at least one part of the surface of the base material layer 1 is performed after a corona treatment process. Although it does not restrict | limit especially as a printing method, When printing on the packaging material for batteries after shaping | molding, pad printing is preferable. In the battery packaging material obtained by the production method of the present invention, the contact angle of the surface on the side of the base material layer 1 is set to 80 ° or less, so that the ink is likely to be repelled in the base material layer having a lubricant on the surface. Ink can also be suitably printed by pad printing. Therefore, for example, printing of barcodes, patterns, characters, and the like can be suitably formed on at least a part of the surface of the base material layer 1. The ink used for printing is as described above.

4). Application of Battery Packaging Material 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 using the battery packaging material of the present invention, with the metal terminals connected to each of the positive electrode and the negative electrode protruding outward. A battery using a battery packaging material is formed by covering the periphery of the element so that a flange portion (a region where the sealant layers are in contact with each other) can be formed, and heat-sealing and sealing the sealant layers of the flange portion. Provided. In addition, when accommodating a battery element using the battery packaging material of the present invention, the battery packaging material of the present invention is used such that the sealant portion is on the inner side (surface in contact with the battery element).

  Since the battery packaging material of the present invention is used for the battery of the present invention, the ink is suitably printed on the surface of the battery after the battery packaging material is molded and the battery element is sealed. Can do. That is, since the battery of the present invention has a surface contact angle set to 80 ° or less, the ink is suitably printed even by pad printing in which the ink is likely to be repelled in the base material layer having the lubricant on the surface. For example, barcodes, patterns, characters, and the like can be suitably formed on at least a part of the surface of the battery.

  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 packaging 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 detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the examples.

Examples 1-6 and Comparative Examples 1 and 2
<Manufacture of battery packaging materials>
By laminating the adhesive layer 5 and the sealant layer 4 by the coextrusion method on the laminate in which the base material layer 1 / adhesive layer 2 / metal layer 3 are sequentially laminated, the base material layer 1 / adhesive layer 2 / metal A battery packaging material comprising a laminate in which layer 3 / adhesive layer 5 / sealant layer 4 were sequentially laminated was produced. Specific production conditions for the battery packaging material are as follows.

In Example 1-6 and Comparative Examples 1 and 2, those shown in Table 1 were used as the resin film (thickness 25 μm) and metal layer 2 (40 μm) constituting the base layer 1, respectively. Each resin film constituting the base material layer 1 is blended with 1200 ppm of erucic acid amide. In addition, the aluminum foil is a metal layer formed by a roll coating method so that a treatment liquid composed of a phenol resin, a chromium fluoride compound (trivalent), and phosphoric acid is 10 mg / m ² (dry weight). The film was applied to both surfaces of the film and baked for 20 seconds under the condition that the film temperature was 180 ° C. or higher.

  First, the laminated body by which the base material layer 1 / adhesion layer 2 / metal layer 3 was laminated | stacked in order was produced. Specifically, an adhesive layer 2 composed of a polyester main agent and an isocyanate curing agent two-component urethane adhesive is formed on one surface (corona-treated surface) of the base material layer 1 so as to have a thickness of 3 μm. Was laminated with the metal layer 3 by a dry lamination method to produce a laminate in which the base layer 1 / adhesive layer 2 / metal layer 3 were laminated in order.

  Next, an acid-modified polypropylene resin constituting the adhesive layer 5 [unsaturated carboxylic acid graft-modified random polypropylene grafted with an unsaturated carboxylic acid (acid-modified PP) and a polypropylene constituting the sealant layer 4 [random copolymer (PP)] And was coextruded onto the surface of the metal layer 3 of the laminate, and an adhesive layer 5 having a thickness of 23 μm and a sealant layer 4 having a thickness of 23 μm were laminated. As described above, a laminate in which the base material layer 1 / adhesive layer 2 / metal layer 3 / adhesive layer 5 / sealant layer 4 were laminated in order was obtained. After cooling the obtained laminated body once, it heated until it became 180 degreeC, the packaging material for batteries was obtained by hold | maintaining the temperature for 1 minute, and heat-processing.

  In Examples 5 and 6, the coating layer 6 was provided on the surface of the base material layer 1 as follows.

(Matte coating)
In Example 5, the surface of the base material layer of the battery packaging material obtained above was mixed with resin (80% by mass) made of polyester polyol and isocyanate curing agent and silica particles (20% by mass). Was printed with a gravure coat to form a mat coating layer having a thickness of 3 μm.

(Ink mat coating)
In Example 6, on the surface of the base material layer of the battery packaging material obtained above, a resin (70% by mass) of polyester polyol and isocyanate curing agent, carbon black (15% by mass), silica particles ( Ink mixed with 15% by mass was printed by gravure coating to form a black mat coating layer having a thickness of 6 μm.

  Furthermore, the surface of the obtained battery packaging material on the substrate layer side was subjected to corona treatment under the following conditions to obtain the battery packaging materials of Examples 1-6 and Comparative Examples 1 and 2. In Table 1, PET / nylon of the base material layer means that a PET layer (12 μm) and a nylon layer (15 μm) are laminated in order from the outermost surface side of the base material layer. The mat coating / nylon means that the mat coating layer 6 is provided on the nylon constituting the base material layer 1, and the black mat coating is the same.

[Corona treatment]
Using a corona surface treatment device (trade name CTW-0212) manufactured by Wedge Corporation, the base material layer of the battery packaging material at a constant speed of 10 MT / min at each output (Kw) set value shown in Table 1 The corona discharge was irradiated to the 1 side surface.

[Evaluation method of ink printing characteristics]
Pad printing was performed on the surface of each battery packaging material of Example 1-6 and Comparative Examples 1 and 2 on the base material layer side, and the printing characteristics of the ink were evaluated. The pad printer used was SPACE PAD 6GX manufactured by Mishima Corporation. The ink used was UV ink PJU-A black manufactured by Navitas. The ink printed on the surface on the substrate layer side was cured by irradiation with UV for 30 seconds from a distance of 10 cm at an ultraviolet wavelength of 254 nm with an As One handy UV lamp SUV-4. The printed surface after curing was observed with an optical microscope, and the printing characteristics of the ink were evaluated according to the following criteria. Ink printing was performed in an environment of 24 ° C. and a relative humidity of 50%. The results are shown in Table 1.
○: Printing failure is within 5% of the entire printed pattern ×: Printing failure is more than 5% of the entire printed pattern

[Measurement of contact angle]
The contact angle of the surface on the base material layer side of each battery packaging material of Example 1-6 and Comparative Examples 1 and 2 was determined using the LSE-A210 manufactured by Nick Co., Ltd. The contact angle of the water droplet interface was measured. The results are shown in Table 1.

  In Table 1, PET means polyethylene terephthalate, and PBT means polybutylene terephthalate.

DESCRIPTION OF SYMBOLS 1 Base material layer 2 Adhesive layer 3 Metal layer 4 Sealant layer 5 Adhesive layer 6 Coating layer

Claims (11)

It consists of a laminate in which at least a base material layer, a metal layer, and a sealant layer are sequentially laminated,
The battery packaging material whose contact angle of the surface at the side of the said base material layer is 80 degrees or less.   The battery packaging material according to claim 1, wherein the battery packaging material is used by printing ink on at least a part of the surface on the substrate layer side.   The battery packaging material according to claim 1, wherein ink is printed on at least a part of the surface on the base material layer side.   The battery packaging material according to any one of claims 1 to 3, wherein the surface on the base material layer side is subjected to corona treatment.   The battery packaging material according to claim 1, wherein an adhesive layer is laminated between the base material layer and the metal layer.   The battery packaging material according to any one of claims 1 to 5, wherein an adhesive layer is laminated between the metal layer and the sealant layer.   The battery packaging material according to any one of claims 1 to 6, wherein the metal layer is formed of an aluminum foil.   The battery packaging material according to any one of claims 1 to 7, wherein a lubricant is present on the surface of the base material layer side.   The battery by which the battery element provided with the positive electrode, the negative electrode, and the electrolyte is accommodated in the packaging material for batteries in any one of Claims 1-8. A laminating step of obtaining a laminate by laminating at least a base material layer, a metal layer, and a sealant layer;
Applying a corona treatment to the surface of the base material layer side so that the contact angle of the surface of the base material layer side is 80 ° or less; and
A method for producing a battery packaging material.   The manufacturing method of the packaging material for batteries of Claim 10 provided with the process of printing ink on at least one part of the surface by the side of a base material layer after the said corona treatment process.