JP7423964B2 - Packaging materials and packaging bodies for all-solid-state lithium-ion batteries - Google Patents

Description

The present invention provides a sulfur-based gas absorbing material for packaging an all-solid-state lithium-ion battery of a sulfide-based inorganic solid electrolyte type, which absorbs sulfur-based gas generated from an all-solid-state lithium-ion battery of a sulfide-based inorganic solid electrolyte type. and a package obtained by packaging a sulfide-based inorganic solid electrolyte type all-solid lithium ion battery with the packaging material.
The packaging material for an all-solid-state lithium-ion battery of the sulfide-based inorganic solid electrolyte type of the present invention can be applied to all-solid-state lithium-ion battery products in various fields, and is particularly suitable for household power storage system applications and automobile electricity storage systems. It can be suitably used as a packaging material for packaging large-capacity all-solid-state lithium ion batteries, such as those used as power sources for motors.

Conventionally, packaging materials used to package lithium-ion batteries have had to have sealing properties and water vapor barrier properties to prevent water vapor from entering from the outside, chemical resistance to prevent electrolyte leakage, and lithium-ion battery heat generation. There has been a demand for improvements in heat resistance, etc., so that the electrolyte will not leak due to melting when the electrolyte is heated (Patent Document 1).
However, in recent years, assuming that the lithium-ion battery package will be used for a long period of time, such as about 20 years in automotive or household applications, in the case of all-solid-state lithium-ion batteries, sulfur is produced by decomposition of the electrolyte during charging. Concerns have begun to arise that the lithium-ion battery packaging may expand or break due to the accumulation of system gases.
As a method for removing sulfur-based gas, a resin film containing a flavonoid-based compound has been proposed (Patent Document 2). However, since flavonoid compounds have poor heat resistance, there are restrictions on the heating conditions in the resin film manufacturing process, and the effect of removing sulfur gases has been insufficient.
Furthermore, as a resin film for removing sulfur-based gases, a resin film containing an antifogging agent made of zeolite, metal silicate containing copper, and glycerin esters has been proposed (Patent Document 3). However, the main focus was on removing moisture and ethylene gas, and the effect of removing sulfur-based gas was insufficient. The adsorption and decomposition mechanism of sulfur-based gas (hydrogen sulfide) in metal silicate proceeds by redox reaction, but in a closed space like a lithium battery package, the oxygen concentration (hydrogen concentration) is also limited. Assuming the approximately 20-year durability required for lithium-ion batteries, this is insufficient from the viewpoint of sustainability of the adsorption effect. The adsorption and decomposition mechanism of sulfur-based gas (hydrogen sulfide) in metal silicate proceeds by redox reaction, but in a closed space like a lithium battery package, the oxygen concentration (hydrogen concentration) is also limited. Assuming the approximately 20-year durability required for lithium-ion batteries, this is insufficient from the viewpoint of sustainability of the adsorption effect. The adsorption and decomposition mechanism of sulfur-based gas (hydrogen sulfide) in metal silicate proceeds by redox reaction, but in a closed space like a lithium battery package, the oxygen concentration (hydrogen concentration) is also limited. Assuming the approximately 20-year durability required for lithium-ion batteries, this is insufficient from the viewpoint of sustainability of the adsorption effect.

Japanese Patent Application Publication No. 2015-38881 Japanese Patent Application Publication No. 1-207339 JP2019-069817A

The present invention solves the above-mentioned problems, has excellent manufacturing suitability, has a simple layer structure, and is capable of absorbing sulfur gas generated from an all-solid-state lithium-ion battery using a sulfide-based inorganic solid electrolyte. A sulfur-based gas-absorbing packaging material for ion batteries, and a sulfur-based gas-absorbing sulfide-based inorganic solid electrolyte type all-solid lithium ion obtained by packaging an all-solid lithium-ion battery with the sulfur-based gas-absorbing packaging material. An object of the present invention is to provide a battery package.

As a result of various studies, the present inventors have discovered that a sulfur-based gas absorbing packaging material for all-solid-state lithium-ion batteries containing a thermoplastic resin and a specific sulfur-based gas absorbent achieves the above objectives. Ta.

That is, the present invention is characterized by the following points.
1. A sulfur-based gas absorbing packaging material for a sulfide-based inorganic solid electrolyte type all-solid lithium ion battery that absorbs sulfur-based gas,
The all-solid-state lithium ion battery packaging material includes at least a base layer made of a base film, a gas barrier layer made of a gas barrier film, and a sealant layer made of a sulfur-based gas absorbing sealant film,
The sulfur-based gas absorbing sealant film contains a sulfur-based gas absorbent and a heat-sealing resin,
The content of the sulfur-based gas absorbent in the layer containing the sulfur-based gas absorbent is 0.3% by mass or more and 30% by mass or less,
Sulfur-based gas absorbing packaging material.
2. The sulfur-based gas absorbent contains a sulfur-based gas chemical absorbent and/or a sulfur-based gas physical absorbent,
The sulfur-based gas-absorbing packaging material described in 1 above.
3. The sulfur-based gas absorbent has a maximum particle size of 20 μm or less and a number average particle size of 0.1 μm or more and 15 μm or less,
The sulfur-based gas absorbing packaging material according to 1 or 2 above.
4. The sulfur-based gas chemical absorbent is a metal oxide and/or an inorganic substance supported or mixed with a metal or metal ion.
The sulfur-based gas absorbing packaging material according to 2 or 3 above.
5. The metal oxide contains one or more selected from the group consisting of CuO, ZnO, and AgO.
The sulfur-based gas absorbing packaging material according to 4 above.
6. The metal species in the inorganic substance supported or mixed with the metal or metal ion is one or two selected from the group consisting of Ca, Mg, Na, Cu, Zn, Ag, Pt, Au, Fe, Al, and Ni. including the above,
The sulfur-based gas absorbing packaging material according to 4 or 5 above.
7. The sulfur-based gas physical absorbent contains one or more selected from the group consisting of hydrophobic zeolite, bentonite, and sepiolite with a SiO ₂ /Al ₂ O ₃ molar ratio of 1/1 to 2000/1.
The sulfur-based gas absorbing packaging material according to any one of 2 to 6 above.
8. The base film contains a polyamide resin and/or a polyester resin,
The sulfur-based gas-absorbing packaging material according to any one of 1 to 7 above.
9. the gas barrier film is aluminum foil;
The sulfur-based gas absorbing packaging material according to any one of 1 to 8 above.
10. A sulfur-based gas-absorbing all-solid-state lithium ion battery package produced from the sulfur-based gas-absorbing packaging material according to any one of 1 to 9 above.

The sulfur-based gas absorption packaging material for all-solid-state lithium-ion batteries of the present invention solves the above-mentioned problems, has excellent manufacturing suitability, has a simple layer structure, and has an all-solid-state lithium-ion sulfide-based inorganic solid electrolyte type. It has excellent absorption properties for sulfur-based gases generated from batteries and excellent heat-sealability, and does not peel or bulge due to sulfur-based gases generated from sulfide-based inorganic solid electrolyte type all-solid lithium-ion batteries. It can produce difficult effects.

FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of the sulfur-based gas absorbing packaging material for an all-solid-state lithium ion battery of the present invention. FIG. 2 is a schematic cross-sectional view showing an example of another embodiment of the layer structure of the sulfur-based gas absorbing packaging material for an all-solid-state lithium ion battery of the present invention. FIG. 2 is a schematic cross-sectional view showing an example of yet another embodiment of the layer structure of the sulfur-based gas absorbing packaging material for an all-solid-state lithium ion battery of the present invention.

In each figure, the sizes and proportions of members may be changed or exaggerated for ease of understanding. Further, for ease of viewing, parts unnecessary for explanation or repetitive symbols may be omitted.
Further, although omitted in each figure, an adhesive layer may be provided between each layer.
Furthermore, if necessary, in order to strengthen the adhesive strength (adhesion strength) between each layer, the laminated surface of each layer may be subjected to physical treatment such as corona discharge treatment, ozone treatment, plasma treatment, glow discharge treatment, sandblasting treatment, etc. A chemical surface treatment such as surface treatment or oxidation treatment using chemicals can also be applied in advance.

The sulfur-based gas absorbing packaging material for a sulfide-based inorganic solid electrolyte type all-solid lithium ion battery of the present invention will be explained in more detail below. Although the present invention will be explained by showing specific examples, the present invention is not limited thereto.

(Gas to be absorbed)
In the present invention, the gas to be absorbed is a sulfur-based gas.
In the present invention, examples of the sulfur-based gas include hydrogen sulfide, dimethyl sulfide, methyl mercaptan, and sulfur oxides represented by _SOx .

≪All-solid-state lithium-ion battery≫
A typical configuration of a lithium ion battery is a positive electrode made of an oxide containing lithium, a negative electrode containing a carbon material, a separator, and an electrolyte.
Here, there are two types of electrolyte: liquid type and solid type, and an all-solid-state lithium ion battery refers to a type where the electrolyte is solid.
In addition, a lithium ion battery is generally a secondary battery that can be charged and discharged by moving lithium ions between a positive electrode and a negative electrode, and in the present invention, the lithium ion battery Refers to the battery.
Solid electrolytes include oxide-based and sulfide-based electrolytes, and sulfide-based electrolytes are preferred because they allow higher output.
The sulfide-based solid electrolyte mentioned above is a compound that easily reacts with moisture to generate sulfur-based gas, and if an all-solid-state lithium-ion battery absorbs moisture, the sulfide-based solid electrolyte containing sulfur-based gas Electrolyte decomposition gas (sulfur-based gas) is generated.
The cumulative amount of sulfur-based gas generated by all-solid-state lithium-ion batteries for automotive applications and home power storage systems, which are expected to be used for approximately 20 years or more, is extremely large, so the pouch used to package all-solid-state lithium-ion batteries There are concerns about expansion and bag breakage due to sulfur-based gas containing sulfur-based gas, and corrosion of metal foil layers such as aluminum foil, and countermeasures are required to address these concerns.

≪Sulfur-based gas absorption packaging material≫
The sulfur-based gas absorbing packaging material for lithium ion batteries of the present invention is particularly suitable for all-solid lithium ion batteries of the sulfide-based inorganic solid electrolyte type, which generate a large amount of sulfur-based gas.
The sulfur-based gas absorbing packaging material for lithium ion batteries of the present invention can absorb the above-mentioned sulfur-based gases generated from solid electrolyte type lithium ion batteries.

The sulfur-based gas-absorbing packaging material for all-solid-state lithium-ion batteries of the present invention comprises at least a base layer made of a base film, a gas barrier layer made of a gas barrier film, and a sealant layer made of a sulfur-based gas absorption sealant film. , the sulfur-based gas absorbing sealant film contains a sulfur-based gas absorbent and a heat-sealable resin, and the sulfur-based gas absorbent contains a chemical sulfur-based gas absorbent and/or a sulfur-based gas physical absorbent. It is preferable.
The gas barrier layer is preferably laminated between the base material layer and the sulfur-based gas absorption layer.
The sulfur-based gas-absorbing packaging material can further include an intermediate layer that performs various functions, if necessary.
Moreover, each layer constituting the sulfur-based gas absorbing packaging material may be laminated with an adhesive layer interposed therebetween.
The sulfur-based gas-absorbing packaging material is a packaging material made from a sulfur-based gas-absorbing laminate including the above-described base layer, gas barrier layer, and sealant layer.
It is preferable that one surface of the sulfur-based gas absorbing packaging material for an all-solid-state lithium ion battery has heat sealability. Therefore, it is preferable that the heat-sealable surface of the sulfur-based gas-absorbing film be laminated so as to constitute one surface of the sulfur-based gas-absorbing packaging material.
The sulfur-based gas-absorbing packaging material further has properties such as processability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slipperiness, mold release properties, flame retardancy, anti-mold properties, and electrical properties. For the purpose of improving or modifying physical properties, strength, etc., various plastic compounding agents and additives can be contained. The content can be arbitrarily determined from a trace amount to several tens of percent depending on the purpose.
In the above, common additives include anti-blocking agents, lubricants, cross-linking agents, antioxidants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins. etc. can be contained.

<Sealant layer>
The sealant layer is a layer containing a sulfur-based gas absorbent and a heat-sealable resin, and has sulfur-based gas absorbency and heat-sealability.
The sealant layer is preferably a layer made of a sulfur-based gas absorbing sealant film.
A sulfur-based gas-absorbing sealant film is a sulfur-based gas-absorbing film that has heat-sealing properties, and includes a sulfur-based gas-absorbing film containing a heat-sealing resin, or a sulfur-based gas-absorbing film containing a layer containing a heat-sealing resin. It can be manufactured by laminating layers.
The sealant layer contains a sulfur gas absorbent to impart sulfur gas absorbency to the sulfur gas absorbent packaging material, and contains a heat sealable resin to impart heat sealability to the sulfur gas absorbent packaging material. It can be applied to materials.
Preferably, the outer surface of the sealant layer has heat sealability by containing a heat sealable resin.
Further, the sealant layer may further include a layer derived from a material other than the sulfur-based gas absorbing sealant film, if necessary. For example, it may further include a support layer for reinforcing support.
The sealant layer may have a single layer structure or may have a multilayer structure of two or more layers having the same or different compositions.
For example, it may be one layer containing a sulfur-based gas absorbent and a heat-sealable resin, or a sulfur-based gas absorption layer containing a sulfur-based gas absorbent and no sulfur-based gas absorbent. There may be two layers including a heat-sealing layer containing a heat-sealable resin. Furthermore, the sulfur-based gas absorption layer includes a layer containing only a sulfur-based gas physical absorbent, a layer containing only a sulfur-based gas chemical absorbent, and a layer containing both a sulfur-based gas physical absorbent and a sulfur-based gas chemical absorbent. Any one type or two or more types of layers may be used. Here, the sulfur-based gas absorption layer may contain a heat-sealing resin.
The thickness of the sealant layer is not particularly limited, but is preferably 10 μm or more and 100 μm or less. If it is thinner than the above range, the rigidity will be too low, it will break easily, and it will be difficult to exhibit sufficient sulfur-based gas absorption effect, and if it is thicker than the above range, the rigidity will be too strong, making it difficult to use as a packaging material. tends to get worse.

≪Sulfur-based gas absorption film≫
The sulfur-based gas absorbing film of the present invention is a gas-absorbing film that absorbs sulfur-based gas.

The sulfur-based gas absorption layer contains at least a thermoplastic resin and a specific sulfur-based gas absorbent.
A sulfur-based gas absorbing film exhibits sulfur-based gas absorption by containing a sulfur-based gas absorbent, and a thermoplastic resin is a resin in which a sulfur-based gas absorbent is dispersed to form the sulfur-based gas absorbing film. Contained as an ingredient.
The sulfur-based gas absorbent may include a sulfur-based gas chemical absorbent and/or a sulfur-based gas physical absorbent.
Furthermore, if necessary, the sulfur-based gas absorbing film may further contain a heat-sealable resin. By further containing a heat-sealing resin, the sulfur-based gas absorbing film can exhibit heat-sealing properties.

The sulfur-based gas absorbing film may have a single layer structure, or may be composed of two or more layers having the same or different compositions.
For example, there may be two layers: a layer containing a sulfur-based gas absorbent (sulfur-based gas absorption layer) and a layer containing no sulfur-based gas absorbent. Further, there may be a layer containing only a sulfur-based gas physical absorbent and a layer containing only a sulfur-based gas chemical absorbent, or a layer containing both a sulfur-based gas physical absorbent and a sulfur-based gas chemical absorbent. There may be layers. Further, there may be layers having different contents of sulfur-based gas absorbent.
The heat-sealable resin may be contained in the sulfur-based gas absorbing layer, or may be contained in a layer that does not contain a sulfur-based gas absorbent to form a heat-sealing layer.
Furthermore, the sulfur-based gas absorbing film can also have a support layer for reinforcing support, if necessary.
The layers constituting the sulfur-based gas absorbing film may be laminated with an adhesive layer interposed therebetween.

The content of the sulfur-based gas absorbent in the layer containing the sulfur-based gas absorbent is preferably 0.5% by mass or more and 30% by mass or less, and more preferably 1% by mass or more and 29% by mass or less. If it is less than the above range, there is a risk that sufficient sulfur-based gas absorption may not be achieved, and if it is more than the above range, sulfur-based gas absorption will not be particularly improved, and interlayer adhesion and heat sealability may deteriorate, or it may become brittle. There is a possibility that this will happen.

Sulfur-based gas absorption films have, for example, processability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slipperiness, mold release properties, flame retardance, anti-mold properties, electrical properties, and strength. Various plastic compounding agents, additives, etc. can be contained for the purpose of improving and modifying plastic materials. The content can be arbitrarily determined from a trace amount to several tens of percent depending on the purpose.
In the above, common additives include anti-blocking agents, lubricants, cross-linking agents, antioxidants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins. etc. can be contained.

Although there is no particular restriction on the thickness of the sulfur-based gas absorbing film, it is preferably 10 μm or more and 100 μm or less. If it is thinner than the above range, the rigidity will be too low, it will break easily, and it will be difficult to exhibit sufficient sulfur-based gas absorption effect, and if it is thicker than the above range, the rigidity will be too strong, making it difficult to use as a packaging material. tends to get worse.

[Sulfur gas absorption layer]
The sulfur-based gas absorbing layer is a layer containing a sulfur-based gas absorbent, and also contains a thermoplastic resin for dispersing the sulfur-based gas absorbent. Further, the sulfur-based gas absorption layer may contain a heat-sealable resin, and if it has sufficient heat-sealability, it can also serve as a sealant layer at the same time.
The thickness of the sulfur-based gas absorption layer is not particularly limited, but is preferably 5 μm or more and 50 μm or less. If it is thinner than the above range, it will be difficult to exhibit sufficient sulfur-based gas absorption effect, and if it is thicker than the above range, the sulfur-based gas absorption effect will not improve much, and the rigidity of the film will become too strong, making it difficult to use as a packaging material. It tends to be difficult to use.

[Sulfur gas absorbent]
The sulfur-based gas absorbent preferably contains a sulfur-based gas physical absorbent and/or a sulfur-based gas chemical absorbent.
By using various sulfur-based gas absorbents in combination, for example, using a sulfur-based gas physical absorbent and a sulfur-based gas chemical absorbent in combination, it becomes possible to easily absorb various sulfur-based gases.
The sulfur-based gas absorbent is used in powder form, and the maximum particle size is preferably 20 μm or less, and the number average particle size of the powder is preferably 0.1 μm or more and 20 μm or less. If the number average particle size is smaller than the above range, the sulfur gas absorbent will tend to aggregate, and if the number average particle size is larger than the above range, the homogeneity of the sulfur gas absorbent film may be poor, and the sulfur gas absorbent may Since the surface area of the sulfur-based gas absorbent becomes smaller, there is a possibility that the absorption of sulfur-based gases will be poor.

The sulfur-based gas absorbent contained in the sulfur-based gas absorption layer is preferably contained through a masterbatch in which the powdered sulfur-based gas absorbent is melt-blended with a thermoplastic resin.
Specifically, a masterbatch is prepared by melt-blending a powdered sulfur-based gas absorbent with a thermoplastic resin at a relatively high concentration, and then a masterbatch is prepared so that the desired concentration in the sulfur-based gas absorption layer is achieved. It is preferable to dry blend the masterbatch and other components before use.
Each of the sulfur-based gas absorbent and thermoplastic resin to be melt-blended may be one type or two or more types.
The content of the sulfur-based gas absorbent in the masterbatch is preferably 20% by mass or more and 90% by mass or less, more preferably 30% by mass or more and 70% by mass or less. Within the above range, it is easy to contain a necessary and sufficient amount of the sulfur-based gas absorbent in a dispersed state in the sulfur-based gas absorption layer.

(Sulfur-based gas physical absorbent)
The sulfur-based gas physical absorbent is a gas absorbent that has the function of physically absorbing the sulfur-based gas to be absorbed.
The sulfur-based gas physical absorbent may contain one or more selected from the group consisting of hydrophobic zeolite, bentonite, and sepiolite with a SiO ₂ /Al ₂ O ₃ molar ratio of 1/1 to 2000/1. preferable.

Hydrophobic zeolite is a zeolite that is excellent in absorbing molecules with low polarity such as sulfur-based gases, and has a porous structure.
In general, the higher the molar ratio of the SiO ₂ /Al ₂ O ₃ components, the higher the hydrophobicity of zeolite. As hydrophobicity increases, it becomes easier to absorb molecules with low polarity such as sulfur-based gases, and conversely, the affinity for molecules with high polarity such as water decreases, making it difficult to absorb them. .
The SiO ₂ /Al ₂ O ₃ molar ratio of the hydrophobic zeolite is preferably from 30/1 to 10,000/1, more preferably from 35/1 to 9,000/1, even more preferably from 40/1 to 8,500/1.
Furthermore, hydrophobic zeolite has high heat resistance and can maintain its absorption effect even when exposed to high temperatures of 230° C. or higher.
In the present invention, a hydrophobic zeolite having a molar ratio within the above range is preferably used in view of the balance between sulfur-based gas absorption ability and availability.

Bentonite is an inorganic substance whose main component is montmorillonite, which is a clay mineral, contains a large amount of layered aluminum phyllosilicate, and contains minerals such as quartz and feldspar as impurities.
For example, bentonite includes Na-type bentonite containing a large amount of Na ⁺ ions, Ca-type bentonite containing a large amount of Ca ²⁺ ions, and artificially converted into Na-type bentonite by adding several wt% of sodium carbonate to Ca-type bentonite. activated bentonite, etc.

_Sepiolite is a clay mineral whose main component is hydrated magnesium silicate. Its general chemical composition is Mg ₈ Si ₁₂ O ₃₀ (OH ₂ ) ₄ (OH) 4.6-8H ₂ O, and it is porous. Has a structure. From the viewpoint of availability, the pH (3% suspension) is preferably 8.0 to 9.0, more preferably 8.9 to 9.3.

(Sulfur-based gas chemical absorbent)
A sulfur-based gas chemical absorbent is a gas absorbent that has the effect of chemically absorbing or decomposing a sulfur-based gas as a gas to be absorbed.
Since the absorption or decomposition is chemical, it is less susceptible to the effects of water and the like, and once absorbed, sulfur-based gas molecules are difficult to desorb, allowing for efficient absorption. In addition, the decomposition products are absorbed by a sulfur-based gas physical absorbent or a sulfur-based gas chemical absorbent.
The sulfur-based gas chemical absorbent preferably contains one or more selected from the group consisting of an inorganic material carrying a metal oxide, a glass mixed with a metal, and a glass mixed with a metal ion.
The metal oxide in the inorganic material supporting the metal oxide preferably contains one or more selected from the group consisting of CuO, ZnO, and AgO.
Further, the supported inorganic material is preferably an inorganic porous material such as zeolite.
The metal in the glass mixed with metal or the metal species of the metal ion in the glass mixed with metal ions is from the group consisting of Ca, Mg, Na, Cu, Zn, Ag, Pt, Au, Fe, Al, and Ni. It is preferable to include one or more selected types.

[Thermoplastic resin]
The thermoplastic resin contained together with the sulfur-based gas absorbent is not particularly limited as long as it has excellent dispersibility of the sulfur-based gas absorbent and can be used as a packaging material.
Moreover, the thermoplastic resin can contain a heat-sealable resin.
The thermoplastic resin preferably contains a polyolefin resin.
Specific examples of polyolefin resins include low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE), and ethylene-vinyl acetate copolymer. ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl methacrylic acid copolymer, ethylene-propylene copolymer, etc., and mixtures of these resins. Can be mentioned.
Among the above, polyethylene-based resins are preferred, and among the polyethylene-based resins, LDPE, LLDPE, general-purpose PE, PE-based copolymers, etc. are more preferred, and LLDPE is even more preferred.

[Heat-sealable resin]
The heat-sealable resin is not particularly limited, and any known resin can be used as long as it can be melted and fused by heat.
Specific examples of heat-sealable resins include polyethylene, low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, metallocene polyethylene, polypropylene, ethylene-vinyl acetate copolymer, and ionomer resin. , ethylene-ethyl (meth)acrylate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-propylene copolymer, methylpentene polymer, polyolefin resin such as polyethylene or polypropylene with acrylic acid, methacrylic acid, Polyolefin resins modified with unsaturated carboxylic acids such as maleic anhydride, fumaric acid, etc., terpolymer resins of ethylene-(meth)acrylic acid ester-unsaturated carboxylic acids, cyclic polyolefin resins, cyclic olefin copolymers, polyethylene Examples include terephthalate (PET) and polyacrylonitrile (PAN).
Among these, polyolefin resins are preferred, polyethylene resins are more preferred, and low density polyethylene and linear low density polyethylene are even more preferred.

[Heat seal layer]
The heat-sealing layer is a layer that contains a heat-sealing resin and has sufficient heat-sealing properties, and may or may not contain a sulfur-based gas absorbent.

[Support layer]
The support layer is a layer that is included as necessary. For example, it is included to supplement the rigidity of the sulfur-based gas-absorbing film, and it also has the effect of preventing blocking when the sulfur-based gas-absorbing film is rolled or stacked. can.
The resin contained in the support layer is preferably LDPE or LLDPE. Further, it may contain a heat-sealing resin.
The thickness of the support layer is not particularly limited, but is preferably 1 μm or more and 50 μm or less. If it is thinner than the above range, it is difficult to exhibit the effect of reinforcing the rigidity, and if it is thicker than the above range, the rigidity is too strong and the usability as a packaging material or packaging material tends to be poor.

<Adhesive layer>
The adhesive used in the adhesive layer is not particularly limited, and dry laminating adhesives, EC (extrusion coat) adhesives, non-solvent laminating adhesives, arbitrary anchor coating agents, and the like can be used.
Further, the adhesive may be of a thermosetting type, an ultraviolet curing type, an electron beam curing type, etc., and may be of any form such as an aqueous type, a solution type, an emulsion type, a dispersion type, etc., and its properties are It may be in any form such as film/sheet form, powder form, solid form, etc. Furthermore, the adhesion mechanism may be in any form such as chemical reaction type, solvent volatilization type, heat melt type, heat pressure type, etc.

Components that form such an adhesive layer include polyvinyl acetate adhesives such as polyvinyl acetate and vinyl acetate-ethylene copolymers, copolymers of polyacrylic acid and polystyrene, polyester, polyvinyl acetate, etc. polyacrylic acid adhesives, cyanoacrylate adhesives, ethylene copolymer adhesives consisting of copolymers of ethylene and monomers such as vinyl acetate, ethyl acrylate, acrylic acid, methacrylic acid, and cellulose adhesives. , polyurethane adhesives, polyester adhesives, polyamide adhesives, polyimide adhesives, polyolefin adhesives such as LDPE, amino resin adhesives made of urea resin or melamine resin, phenolic resin adhesives, epoxy adhesives, reactive (meth)acrylic adhesives, elastomer adhesives made of chloroprene rubber, nitrile rubber, styrene-butadiene rubber, etc., inorganic adhesives made of silicone adhesives, alkali metal silicates, low-melting glass, etc. agents, etc.

[Sulfur-based gas absorption sealant film]
The sulfur-based gas-absorbing sealant film is a sealant film made from a sulfur-based gas-absorbing film, and has the same sulfur-based gas absorption as the sulfur-based gas-absorbing film and excellent heat sealability.
If the sulfur-based gas-absorbing film has sufficient heat sealability and supportability, the sulfur-based gas-absorbing film can be used as it is as a sulfur-based gas-absorbing sealant film, and if necessary, a support layer may be added. A sulfur-based gas absorbing sealant film can also be produced by laminating, containing a heat-sealing resin, or laminating layers containing a heat-sealing resin.

The sulfur-based gas absorbing sealant film may have a single layer structure or a multilayer structure of two or more layers.
In the case of a multilayer structure, a sulfur-based gas-absorbing sealant film can be produced by laminating a support layer and a heat-sealing layer on a layer derived from a sulfur-based gas-absorbing film. Then, if necessary, various functional layers can be further laminated to produce a sulfur-based gas absorbing sealant film. Here, each layer constituting the sulfur-based gas absorbing sealant film may be laminated with an adhesive layer interposed therebetween.
It is preferable that one or both surfaces of the sulfur-based gas-absorbing sealant film have heat-sealing properties. For that purpose, for example, a heat-sealing layer is laminated on one or both surfaces of the sulfur-based gas-absorbing sealant film. You may.
By having heat-sealing properties on both sides of the sulfur-based gas-absorbing sealant film, it is possible to produce a sulfur-based gas-absorbing laminate with excellent interlayer adhesion and heat-sealing properties inside the sulfur-based gas-absorbing laminate.

The thickness of the sulfur-based gas absorbing sealant film is not particularly limited, but is preferably 10 μm or more and 100 μm or less. If it is thinner than the above range, the rigidity will be too low, it will break easily, and it will be difficult to exhibit sufficient sulfur-based gas absorption effect, and if it is thicker than the above range, the rigidity will be too strong, making it difficult to use as a packaging material. tends to get worse.

<<Method for producing sulfur-based gas absorption film and sulfur-based gas absorption sealant film>
The manufacturing method shown below is one example and does not limit the present invention.
The method for forming and laminating the sulfur-based gas absorbing film or the sulfur-based gas absorbing sealant film and each layer constituting them is not particularly limited, and any known or conventional film forming method or laminating method can be applied.
The sulfur-based gas-absorbing film or sulfur-based gas-absorbing sealant film is produced by known film forming methods and/or lamination methods such as (co)extrusion method, cast molding method, T-die method, cutting method, and inflation method. It can be carried out.
When the sulfur-based gas-absorbing film or the sulfur-based gas-absorbing sealant film is composed of two or more layers, for example, the films constituting each layer prepared in advance may be laminated via an adhesive layer, A molten resin composition may be laminated by (co-)extrusion on a layer prepared in advance, a plurality of layers may be laminated by melt-pressing while simultaneously preparing them, or one type of resin composition may be laminated on another layer by melt-pressing. Alternatively, two or more resins may be applied and dried for coating.
For example, an example can be described in which a sulfur-based gas-absorbing sealant film is produced by laminating a heat-sealing layer on a sulfur-based gas-absorbing film.

A sulfur-based gas absorption layer or a heat-sealing layer is laminated on top of other layers by extrusion or coextrusion using an extrusion coating method, or laminated via an adhesive layer after film formation by an inflation method or casting method. You can also do that. Even in the case of the extrusion coating method, lamination may be performed via an adhesive layer if necessary.
Alternatively, pre-formed films for the sulfur-based gas absorption layer and films for the heat seal layer are laminated and bonded via an adhesive layer laminated by an extrusion coating method, dry lamination method, non-solvent lamination method, etc. You may.
Then, aging processing may be performed as necessary.

For example, when laminating a sulfur-based gas absorption layer or a heat seal layer using the extrusion coating method, first, the resin composition forming the layer is heated and melted, and then expanded in the required width direction with a T-die. The molten resin is stretched and (co-)extruded into a curtain shape, and the molten resin is allowed to flow down onto the surface to be laminated, and then sandwiched between a rubber roll and a cooled metal roll, thereby forming the layer, laminating the resin onto the surface to be laminated, and Bonding can be done simultaneously.
The melt flow rate (MFR) of the resin component contained in each layer when laminated by extrusion coating is preferably 0.2 to 50 g/10 minutes, more preferably 0.5 to 30 g/10 minutes. If the MFR is smaller or larger than the above range, processing suitability tends to be poor. Note that in this specification, MFR is a value measured using a method based on JIS K7210.

When using the inflation method, the melt flow rate (MFR) of the resin component contained in each layer is preferably 0.2 to 10 g/10 minutes, more preferably 0.2 to 9.5 g/10 minutes. If the MFR is smaller or larger than the above range, processing suitability tends to be poor.

Additionally, in order to improve adhesion between the layers constituting the sulfur-based gas absorbing film or the sulfur-based gas absorbing sealant film, the surface of each layer may be subjected to a desired surface treatment in advance, if necessary. can.
For example, pretreatment such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, oxidation treatment using chemicals, etc. is optionally performed to form a corona treatment layer, ozone treatment, etc. A layer, a plasma treatment layer, an oxidation treatment layer, etc. can be formed and provided.
Alternatively, various coating agent layers such as a primer coating agent layer, an undercoating agent layer, an anchor coating agent layer, an adhesive layer, and a vapor-deposited anchor coating agent layer can be optionally formed on the surface to form a surface treatment layer. .
The various coating agent layers mentioned above include, for example, polyester resins, polyamide resins, polyurethane resins, epoxy resins, phenol resins, (meth)acrylic resins, polyvinyl acetate resins, and polyolefins such as polyethylene or polypropylene. Resin compositions in which the main component of the vehicle is a resin, a copolymer or modified resin thereof, a cellulose resin, etc. can be used.

Each layer constituting the sulfur-based gas-absorbing film or the sulfur-based gas-absorbing sealant film is further uniaxially or biaxially stretched by a conventionally known method using a tenter method, a tubular method, etc., as necessary. can do.

≪Sulfur-based gas absorption laminate≫
The sulfur-based gas-absorbing laminate of the present invention is a laminate obtained by laminating the sulfur-based gas-absorbing film of the present invention or the sulfur-based gas-absorbing sealant film of the present invention, for example, a base material layer or a gas barrier layer, It absorbs sulfur gases similar to sulfur gas absorption films.
The sulfur-based gas absorbing laminate can further include an intermediate layer that performs various functions, if necessary.
One surface of the sulfur-based gas absorbing laminate is preferably a heat-sealing layer because the sulfur-based gas-absorbing laminate has heat-sealing properties.
The gas barrier layer is preferably laminated between the base material layer and the sulfur-based gas absorption layer.
Moreover, each layer constituting the sulfur-based gas absorption laminate may be laminated with an adhesive layer interposed therebetween.
Then, aging processing may be performed as necessary.

The sulfur-based gas absorbing laminate or each layer constituting the sulfur-based gas absorbing laminate has properties such as processability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidation properties, slipperiness, mold releasability, and difficulty. Various plastic compounding agents, additives, etc. can be contained for the purpose of improving or modifying flammability, anti-mold properties, electrical properties, strength, etc. The content can be arbitrarily determined from a trace amount to several tens of percent depending on the purpose.
In the above, common additives include anti-blocking agents, lubricants, cross-linking agents, antioxidants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins. etc. can be contained.

<Base material layer>
The material for the base layer has excellent mechanical, physical, chemical, and other properties, and is particularly strong, tough, and heat resistant. material film can be used. As the base film, various resin films can be used, and furthermore, various paper base materials can be used, and a resin film and a paper base material can also be used in combination.
The base material layer may be composed of one layer, or may be composed of two or more layers having the same or different compositions and laminated by any laminating means.
The thickness of the base material layer can be set appropriately by those skilled in the art, but for the purpose of imparting appropriate strength and stiffness to the laminate, the thickness of the base material layer is preferably 5 μm to 100 μm, and preferably 10 μm to 100 μm. The thickness is more preferably 50 μm, and even more preferably 5 to 25 μm.

Specific resin films include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate, polyolefin resins such as polypropylene, polyamide resins such as nylon, polyaramid resins, polycarbonate resins, polyacetal resins, and fluorine resins. Examples include resin films made using tough thermoplastic resins such as thermoplastic resins and other tough thermoplastic resins.
The above-mentioned resin film can be either an unstretched film or a uniaxially or biaxially stretched stretched film.
Among the above, resin films containing polyester resins and/or polyamide resins are preferred, and biaxially stretched PET films and biaxially stretched nylon films are more preferably used.

The paper base material can be imparted with shapeability, bending resistance, rigidity, etc., such as bleached or unbleached paper base material for paper layers with strong size properties, pure white roll paper, kraft paper, etc. Paper base materials such as paperboard, processed paper, milk base paper, and others can be used.
The paper base material preferably has a basis weight of about 30 g/m ² to 600 g/m ² , more preferably about 50 g/m ² to 450 g/m ² .

The resin film used for the base layer has processability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slipperiness, mold releasability, flame retardance, and anti-mold properties, as necessary. , plastic compounding agents such as lubricants, crosslinking agents, antioxidants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, etc., for the purpose of improving and modifying electrical properties, strength, etc. Additives and the like can be added in any amount depending on the purpose as long as they do not adversely affect other performances.
Furthermore, a printed layer can be provided on one or both sides of the base layer.

[Printing layer]
The printing layer may contain, for example, letters, numbers, figures, symbols, patterns, patterns, etc., for decoration, display of contents, display of expiration date, display of manufacturer, seller, etc., and for imparting aesthetic appearance. It visually shows a design pattern such as, and can form a desired design pattern.
The printing layer is preferably formed on one or both sides of the base layer by a printing method such as a gravure printing method or a flexographic printing method. The printing layer may be provided on the entire surface of the printing surface, or may be provided on a part of the surface.
If the printing layer is formed inside the laminate, the adhesion of the printing layer can be improved, and ink rubbing or peeling of the printing layer due to external impact or friction can be suppressed.
When the printed layer is included inside the laminate, it is preferable that the layer located outside the printed layer at the time of packaging formation be transparent so that the printed layer can be visually recognized.

[Gas barrier layer]
The barrier layer is a layer that suppresses gas permeation, and when a sulfur-based gas-absorbing package is manufactured, it prevents oxygen and water vapor from entering the content storage area inside the package from the outside of the sulfur-based gas-absorbing package. It is possible to suppress the diffusion of gas components generated from the contents to the outside of the barrier layer. Furthermore, the permeation of the gas to be absorbed in the present invention can be similarly suppressed.
Various barrier materials can be used for the gas barrier layer. In addition, it may be a barrier material that has a light-shielding property not only against oxygen and water vapor, but also against sunlight, etc., and a fragrance-retaining property against the contents. Further, a barrier material having gas barrier properties against water vapor, etc., light shielding properties against sunlight, etc., aroma retention properties against contents, etc. may be used in combination.

As the above-mentioned barrier material, it is preferable to use a gas barrier film, and specifically, for example, a metal foil, a resin film having an inorganic vapor deposited layer, a resin coating film or a resin film made of an oxygen barrier resin, One or more types selected from the group consisting of can be used.
In particular, a resin film having a metal vapor deposited layer, a resin film having a metal oxide vapor deposited layer, a resin coating film or a resin film made of a barrier resin, has oxygen gas, water vapor, light shielding properties, and fragrance retention. It is preferable because it has excellent barrier properties such as water resistance and is environmentally friendly in terms of container disposal.

A specific example of metal foil is aluminum foil. The thickness of the aluminum foil is preferably 5 μm to 50 μm.
Examples of the inorganic compound forming the inorganic vapor deposition layer include metals, metal oxides, metal nitrides, metal carbides, and the like.
Specific examples of the metal elements constituting the above-mentioned inorganic compounds include aluminum (Al), silicon (Si), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na ), boron (B), titanium (Ti), lead (Pb), zirconium (Zr), yttrium (Y), zinc (Zn), vanadium (V), barium (Ba), chromium (Cr), etc. .

In addition to these, indium tin oxide (ITO), Si produced by chemical vapor deposition, etc.
Composite inorganic compounds such as O _X C _Y films may also be mentioned.

As the inorganic material for vapor deposition used in the resin film having the vapor deposited layer, silicon oxide and aluminum oxide are preferable.
The average composition of inorganic compounds is expressed as MO _{x ,} MO _{x C y (} wherein, M represents a metal _element , and x, y The range varies depending on the metal element.) In the case of metal oxides, the range of the value of X is, for example, 0 to 2 for silicon, 0 to 1.5 for aluminum, 0 to 1 for magnesium, 0 to 1 for calcium, and 0 to 1 for potassium. 0.5, tin 0-2, sodium 0-0.5, boron 0-1, 5, titanium 0-2, lead 0-1, zirconium 0-2, yttrium can take values ranging from 0 to 1.5.
In the above MO _x , when x=0, it is a metal, for example, and the upper limit of the range of x is the value when completely oxidized.

For packaging material applications, silicon oxide and aluminum oxide are preferably used, with silicon oxide having x in the range of 1.0 to 2.0, and aluminum oxide having x in the range of 0.5 to 1.5. It is preferable to use
The gas barrier layer may be formed of one type of these barrier materials, or may be used in combination of two or more types, or may be used as a mixture of two or more types. Further, it may be composed of one layer, or may be composed of multiple layers having the same or different compositions, and in the case of multiple layers, they do not need to be stacked adjacently.

Since the resin film supporting the vapor deposited layer is provided with the vapor deposited layer, it has excellent mechanical, physical, chemical, and other properties, and is particularly strong and tough. In addition, a resin film having heat resistance can be used.

Specifically, in the present invention, examples of the resin film supporting the vapor deposition layer include polyester resin films such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), and polyamide resin films such as various types of nylon. , polyolefin films such as polyethylene resin, polypropylene resin, cyclic polyolefin resin, polystyrene resin, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), polybutene resin film, Vinyl chloride resin, polycarbonate resin, polyimide resin, polyamideimide resin, polyaryl phthalate resin, silicone resin, polysulfone resin, polyphenylene sulfide resin, polyether sulfone resin, polyurethane resin, cellulose resin, Poly(meth)acrylic resin, polyvinylidene chloride film, acetal resin film, fluorine resin, and others can be used.
In addition, in the present invention, it is particularly preferable to use a film of polypropylene resin, polyester resin, or polyamide resin.

Methods for forming the inorganic vapor deposition layer include using the above-mentioned inorganic compounds as raw materials and employing physical vapor deposition methods such as vacuum evaporation, sputtering, ion plating, cluster ion beam, and PVD. ), or by using a chemical vapor deposition method (CVD method) such as a plasma chemical vapor deposition method, a thermal chemical vapor deposition method, or a photochemical vapor deposition method, etc., to deposit on a resin film. layers can be formed.

More specifically, in the above-mentioned PVD method, for example, a winding type vapor deposition machine is used, and the resin film released from the unwinding roll is put into the vapor deposition chamber in a vacuum chamber, and here, The vapor deposition source heated in the crucible is evaporated, and if necessary, an inorganic vapor deposition layer is formed on the resin film on the cooled coating drum via a mask while blowing out oxygen etc. from the oxygen outlet. Then, by winding up the resin film on which the inorganic vapor deposited layer is formed onto a take-up roll, the resin film having the inorganic vapor deposited layer according to the present invention can be manufactured.

On the other hand, in the above-mentioned CVD method, a monomer, such as a monomer supplied from a vapor deposition raw material volatilization supply device, is applied to the surface of the resin film fed out from an unwinding roll disposed in the vapor deposition chamber, while cooling in the vapor deposition chamber and on the circumferential surface of the electrode drum. A mixed gas consisting of an organic silicon compound, oxygen gas, and inert gas is introduced, and a resin film on which an inorganic vapor deposited layer of silicon oxide or the like is formed can be produced by plasma. In the present invention, the resin film having the inorganic vapor deposited layer as described above prevents oxygen gas, water vapor, etc. from permeating therethrough, and functions as a gas barrier layer against these.

In the above, the thickness of the deposited layer is preferably 30 Å to 3000 Å, more preferably 40 Å to 2500 Å, and even more preferably 50 Å to 2000 Å, in order to obtain sufficient barrier properties.
More specifically, in the above-mentioned PVD method, the thickness of the deposited layer made of aluminum oxide is preferably about 30 Å to 1000 Å, more preferably about 50 Å to 500 Å.
Furthermore, in the above CVD method, the thickness of the deposited layer made of silicon oxide is preferably 30 Å to 3000 Å, more preferably 50 Å to 2000 Å.
In addition, in the above, in the case of a deposited layer made of a metal oxide or an inorganic substance, if the thickness of the deposited layer exceeds the above range, cracks etc. will easily occur in the deposited layer, and the barrier properties will deteriorate due to warping. This is not preferable because it is dangerous and increases material cost. Moreover, if it is less than the above range, it becomes difficult to exhibit barrier properties, which is not preferable.

Furthermore, the resin film having the inorganic vapor-deposited layer preferably has a water vapor permeability of 3.0 g/m ² ·day or less when measured in accordance with JIS K7129 method in an environment of a temperature of 40° C. and a humidity of 100% RH. , more preferably 2.0 g/m ² ·day or less, still more preferably 1.5 g/m ² ·day or less. If the water vapor permeability satisfies the above-mentioned numerical range, it is possible to sufficiently suppress the intrusion of water vapor from the outside of the package into the content storage section inside the package.
Furthermore, the resin film having the inorganic vapor-deposited layer preferably has an acidity permeability of 3.0 cc/m ² ·atm · day or less when measured in accordance with the JIS K7126 method in an environment of a temperature of 23°C and a humidity of 90% RH. It is more preferably 2.0 cc/m ² ·atm · day or less, and even more preferably 1.0 cc/m ² ·atm · day or less. If the oxygen permeability satisfies the above-mentioned numerical range, it is possible to sufficiently suppress the intrusion of oxygen from the outside of the package into the content storage section inside the package.

A barrier resin coating film or a barrier resin film made of a barrier resin can also be used as a barrier material, and can also exhibit aroma retention properties.
Examples of barrier resins include polyvinylidene chloride resins (PVDC), polyester resins, polyamide resins (especially aromatic polyamides such as nylon MXD6), and ethylene-vinyl acetate copolymers (approximately 79 wt% or more of vinyl acetate). Films or coatings of resins with rich gas barrier properties such as ethylene-vinyl alcohol copolymer (EVOH) with an ethylene content of 25 mol% to 50 mol%, polyvinyl alcohol, polyacrylonitrile, and others, which are completely saponified of 92 wt%). Membranes can be used.
The thickness of the barrier resin coating film or barrier resin film is arbitrary, but preferably 0.5 μm to 300 μm, more preferably 1 μm to 100 μm.
As the gas barrier film, a metal foil or a resin film having a vapor deposited layer is preferable, and an aluminum foil is particularly preferable.

[Preparation of sulfur-based gas absorption packaging material]
For example, an example will be described in which a sulfur-based gas-absorbing laminate is produced by laminating a base material layer and a gas barrier layer on a sulfur-based gas-absorbing sealant film. The manufacturing method shown below is one example and does not limit the present invention.
The base material layer and the gas barrier layer can be laminated by laminating methods used when manufacturing ordinary packaging materials, such as wet lamination, dry lamination, solvent-free dry lamination, extrusion lamination, and T-die coextrusion. It can be carried out by any method such as a molding method, a coextrusion lamination method, an inflation method, and others.
For example, a base material layer, a gas barrier layer, and a sulfur-based gas-absorbing sealant film are laminated and bonded via an adhesive layer laminated by an extrusion coating method, a dry laminating method, a non-solvent laminating method, etc. A gas absorption laminate can be obtained.

When laminating by the extrusion coating method, first, the resin composition forming the adhesive layer is heated and melted, expanded and stretched in the required width direction with a T die, and (co)extruded into a curtain shape. By flowing the molten resin onto the surface to be laminated and sandwiching it between a rubber roll and a cooled metal roll, the formation of the adhesive layer and the lamination and adhesion to the surface to be laminated can be performed simultaneously.
Alternatively, for example, first, dry lamination adhesive is applied to one side of the resin film for the base material layer, dried, and adhered and laminated with the film for the barrier layer, and then dry lamination is applied to the surface of the barrier layer. A sulfur-based gas-absorbing laminate can be obtained by applying an adhesive, drying it, and adhering and laminating it with a sulfur-based gas-absorbing sealant film.
Then, aging processing may be performed as necessary.
In this way, a sulfur-based gas absorbing laminate can be obtained.

≪Sulfur-based gas absorbing all-solid-state lithium-ion battery package≫
The sulfur-based gas-absorbing all-solid-state lithium ion battery package of the present invention is a package produced by packaging an all-solid-state lithium-ion battery using the sulfur-based gas-absorbing packaging material of the present invention.
In the sulfur-based gas absorbing all-solid-state lithium-ion battery package, even if the gas to be absorbed is generated from the all-solid-state lithium-ion battery, the gas to be absorbed is not contained in the sulfur-based gas-absorbing all-solid-state lithium-ion battery package. Since the sulfur-based gas-absorbing packaging material that constitutes the body absorbs the sulfur-based gas, the sulfur-based gas-absorbing all-solid-state lithium ion battery packaging is unlikely to peel or bulge.

<Raw materials>
The main raw materials used in the examples of the present invention are as follows.

<Sulfur-based gas absorbent>
[Physical sulfur gas absorbent]
[Chemical sulfur gas absorbent]

[Thermoplastic resin, heat-sealable resin]
- LDPE1: LDPE manufactured by Japan Polyethylene Co., Ltd., Novatec LC520. Density: 0.923 g/cm ³ , MFR: 3.6 g/10 min.
- LLDPE 1: LLDPE manufactured by Prime Polymer Co., Ltd., Urtozex 4020L. Density: 0.937 g/cm ³ , MFR: 2.3 g/10 min.
・LLDPE2: LLDPE manufactured by Prime Polymer Co., Ltd., Evolue SP2020. Density: 0.916 g/cm ³ , MFR: 2.0 g/10 minutes.
- PP1: PP manufactured by Nippon Polypropylene Co., Ltd., Wintec WFW4M. Density: 0.9 g/cm ³ , MFR: 7.0 g/10 minutes.

[others]
- Nylon film 1: Nylon film manufactured by Toyobo Co., Ltd., Harden film NAP02. 25 μm thick - PET film 1: manufactured by Toyobo Co., Ltd. Biaxially stretched PET film, E5100. 12 μm thick.
- Aluminum foil 1: Aluminum foil manufactured by Toyo Aluminum Co., Ltd., 8021 material. 40μm thick.
- DL adhesive 1: Dry laminating adhesive manufactured by Rock Paint Co., Ltd., RU-004/H-1.
- EC adhesive 1: Acid-modified polyethylene manufactured by Mitsui Chemicals, Inc., Admer NF528.
・EC adhesive 2: Acid-modified polypropylene manufactured by Mitsui Chemicals, Inc., Admer QF551,

<Preparation of masterbatch>
[Preparation of masterbatch 1]
Master batch 1 (MB1) was obtained by melt blending LDPE 1 and chemical absorbent 1, which is a sulfur-based gas chemical absorbent, in the following proportions.
LDPE1 90 parts by mass Chemical absorbent 1 10 parts by mass

[Preparation of masterbatches 2 to 22]
According to the formulations in Tables 1 and 2, melt blending was performed in the same manner as masterbatch 1 to obtain masterbatches 2 to 22 (MB2 to 22).

[Example 1]
The following raw materials were mixed by dry blending to obtain a resin composition for a sulfur-based gas absorption layer.
MB1 50 parts by mass LLDPE1 50 parts by mass Next, nylon film 1 for the base layer and aluminum foil 1 for the gas barrier layer were dry laminated using DL adhesive 1 (coating amount 3.5 g/m ² ). (Drying temperature: 70° C.) to produce a laminated film of nylon film 1 (25 μm)/DL adhesive 1 (3.5 g/m ² )/aluminum foil 1 (40 μm).
Then, on the aluminum foil 1 side of the laminated film obtained above, the EC adhesive 1 and the resin composition for a sulfur-based gas absorption layer obtained above were coextruded, and a sulfur-based gas absorbing layer having the following layer structure was applied by coextrusion lamination. A gas absorbing packaging material was obtained. Then, various evaluations were conducted.
Layer configuration: Nylon film 1 (thickness 25 μm) / DL adhesive 1 (coating amount 3.0 g/m2) / Aluminum foil 1 (thickness 40 μm) / EC adhesive 1 (thickness 15 μm) / Sulfur-based gas absorption layer (thickness 30 μm) )

[Examples 2 to 26, Comparative Examples 3 and 4]
Select a masterbatch and prepare a resin composition for a sulfur-based gas absorption layer according to the descriptions in Tables 3 to 8,
Materials for each layer were selected and operated in the same manner as in Example 1 to obtain a sulfur-based gas absorbing packaging material, which was evaluated in the same manner.

[Comparative example 1]
According to the description in Table 5, a heat seal layer made of LLDPE1 was formed in place of the sulfur-based gas absorption layer by operating in the same manner as in Example 1, and a packaging material was obtained and evaluated in the same manner.

[Comparative example 2]
According to the description in Table 5, a heat seal layer made of PP1 was formed in place of the sulfur-based gas absorption layer by operating in the same manner as in Example 1 to obtain a packaging material, which was evaluated in the same manner.

<Result summary>
The sulfur-based gas absorbing laminates of all Examples of the present invention exhibited good manufacturability, heat sealability, and reduced sulfur-based gas concentration.
However, Comparative Example 1, which did not contain a sulfur-based gas absorbent, was poor in reducing the sulfur-based gas concentration, and Comparative Example 2, which contained too much sulfur-based gas absorbent, had poor heat sealability.
Comparative Examples 3 and 4 had poor heat sealing properties, so subsequent evaluations were discontinued, and sulfur-based gas concentrations were not measured and evaluated.

<Evaluation>

[Manufacturing suitability]
The appearance of the laminate was visually observed, and the presence or absence of defects was evaluated using the following evaluation criteria.
Good: There were no wrinkles, bumps, or peeling in the laminate.
×: There were wrinkles, bumps, and peeling in the laminate.

[Heat sealability]
Cut the laminate into 10 cm x 10 cm pieces, overlap the sealant surfaces, and use a heat seal tester (manufactured by Tester Sangyo Co., Ltd.: TP-701-A) to heat seal a 1 cm x 10 cm area under the following conditions to seal the edges. A peel strength test piece was prepared in which the sample was not heat-sealed or bonded, but was separated into two parts.
This test piece was cut into strips with a width of 15 mm, each end of which was split into two was attached to a tensile tester, and the peel strength (N/15 mm) was measured under the following conditions. Pass/fail judgment was made.
Heat sealing conditions Temperature: 160℃
Pressure: 1kgf/ ^cm2
Time: 1 second Test conditions Test speed: 300mm/min Load range: 50N
Pass/Fail Judgment Criteria ○: 30N/15mm or more, passed.
×: Less than 30N/15mm, failing.

[Sulfur gas concentration]
The laminate was cut into 20 x 20 cm pieces, and 1000 ml of the test gas adjusted to 30 ppm hydrogen sulfide and 50 ppm dimethyl sulfide as sulfur-based gas components was sampled in a gas sampling bag (manufactured by GL Sciences, Inc., SMART BAG PA series). After being left at 25° C. for 48 hours, the concentrations of hydrogen sulfide and dimethyl sulfide were measured using a detection tube.

1 Sulfur-based gas absorption packaging material 2 Base layer 3 Intermediate layer 4 Gas barrier layer 5 Sealant layer 6 Sulfur-based gas absorption layer 7 Sulfur-based gas absorbent 8 Heat seal layer

Claims (5)

A sulfur-based gas absorbing packaging material for a sulfide-based inorganic solid electrolyte type all-solid lithium ion battery that absorbs sulfur-based gas,
The all-solid-state lithium ion battery packaging material includes at least a base layer made of a base film, a gas barrier layer made of a gas barrier film, and a sealant layer made of a sulfur-based gas absorbing sealant film,
The sulfur-based gas absorbing sealant film contains a sulfur-based gas absorbent and a heat-sealing resin,
The sulfur-based gas absorbent contains a sulfur-based gas chemical absorbent and/or a sulfur-based gas physical absorbent,
The sulfur-based gas chemical absorbent is a metal oxide and/or an inorganic substance supported or mixed with a metal or metal ion,
The metal oxide contains one or more selected from the group consisting of CuO and AgO,
The metal species in the inorganic substance supported or mixed with the metal or metal ion is one or more selected from the group consisting of Ca, Mg, Na, Cu, Ag, Pt, Au, Fe, Al, and Ni. including,
The sulfur-based gas physical absorbent contains one or more selected from the group consisting of hydrophobic zeolite and bentonite with a SiO ₂ /Al ₂ O ₃ molar ratio of 30/1 to 2000/1,
The content of the sulfur-based gas absorbent in the layer containing the sulfur-based gas absorbent is 0.3% by mass or more and 30% by mass or less,
Sulfur-based gas absorbing packaging material. The sulfur-based gas absorbent has a maximum particle size of 20 μm or less, and a number average particle size of 0.1 μm or more and 15 μm or less.
The sulfur-based gas absorbing packaging material according to claim 1 . The base film contains a polyamide resin and/or a polyester resin,
The sulfur-based gas absorbing packaging material according to claim 1 or 2 . the gas barrier film is aluminum foil;
The sulfur-based gas absorbing packaging material according to any one of claims 1 to 3 . A sulfur-based gas-absorbing all-solid-state lithium ion battery package produced from the sulfur-based gas-absorbing packaging material according to any one of claims 1 to 4 .

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