Wrap film and wrap film container

Abstract

To provide a wrapping film having transparency and excellent in antiviral properties.SOLUTION: A wrapping film in one aspect of the present invention contains thermoplastic resin, a silver-contained additive and a glycerin anti-fogging agent. The silver-contained additive contains at least one selected from a group consisting of a silver antimicrobial agent and a silver antivirus agent. The glycerin anti-fogging agent contains polyglyceryl fatty acid ester having an ester structure derived from fat acid having 8-22C.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a wrap film and a wrap film container.

Background Art

[0002] Conventionally, wrap films have been widely used for business purposes in hotels, restaurants, etc., or for food preservation and cooking at home. Various improvements have been made to wrap films to enhance convenience during use. For the purpose of identification when fragments of a wrap film are mixed into the packaged product, a food packaging film containing a blue coloring agent is known (see, for example, Patent Document 1). Also, it is known that adding an inorganic antibacterial agent containing a metal such as Ag, Mn, Fe, Co, Ni, Cu, Zn, etc. is effective for imparting antibacterial properties to a wrap film (see, for example, Patent Document 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] There is a need for a wrap film to have not only antibacterial properties but also improved antiviral properties. It is difficult to obtain a wrap film with sufficient antiviral properties simply by adding an antibacterial agent to a wrap film. Although it is expected to improve the antiviral properties of a wrap film by increasing the amount of the antibacterial agent added, the transparency of the wrap film decreases as the amount of the antibacterial agent added increases.

[0005] An object of the present disclosure is to provide a wrap film having transparency and excellent antiviral properties. [Means for solving the problem]

[0006] One aspect of this disclosure relates to a wrap film containing a thermoplastic resin, a silver-containing additive, and a glycerin-based antifogging agent, wherein the silver-containing additive comprises at least one selected from the group consisting of silver-based antibacterial agents and silver-based antiviral agents, and the glycerin-based antifogging agent comprises a polyglycerin fatty acid ester having an ester structure derived from a fatty acid with 8 to 22 carbon atoms.

[0007] The glycerin-based anti-fogging agent according to this disclosure may include a polyglycerin fatty acid ester having a structure represented by the following formula (1). In the formula, R represents an aliphatic hydrocarbon group having 7 to 21 carbon atoms, and n represents a number from 1 to 4. [ka]

[0008] Another aspect of this disclosure relates to a wrap film container comprising a core, the wrap film wound around the core, and a box for housing the core and the wrap film. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a wrap film that is transparent and has excellent antiviral properties. [Brief explanation of the drawing]

[0010] [Figure 1] A perspective view showing a wrap film container according to one embodiment. [Modes for carrying out the invention]

[0011] The embodiments of this disclosure will be described in detail below with reference to the drawings as appropriate. However, this disclosure is not limited to the embodiments described below.

[0012] [Wrap film] A wrap film according to one embodiment contains a thermoplastic resin, a silver-containing additive, and a glycerin-based antifogging agent. The silver-containing additive includes at least one selected from the group consisting of silver-based antibacterial agents and silver-based antiviral agents, and the glycerin-based antifogging agent includes a polyglycerin fatty acid ester having an ester structure derived from a fatty acid with 8 to 22 carbon atoms. Such a wrap film is a film for wrapping articles and is particularly suitable for use as a food packaging film. The wrap film according to this embodiment can achieve both transparency and antiviral properties by adding a specific silver-containing additive and a glycerin-based antifogging agent to the thermoplastic resin.

[0013] (thermoplastic resin) The thermoplastic resin may be a polyester resin such as polyethylene terephthalate, polyethylene naphthalate, or polybutylene terephthalate; a polyamide resin such as nylon 6, nylon 6,6, or nylon 12; a polystyrene resin such as butadiene-styrene copolymer, acrylonitrile-styrene copolymer, polystyrene, styrene-butadiene-styrene copolymer, styrene-isoprene-styrene copolymer, or styrene-acrylic acid copolymer; a polylactic acid resin such as poly-L-lactic acid, poly-D-lactic acid, or poly-DL-lactic acid; a polyolefin resin such as polyethylene, polypropylene, or ethylene-vinyl acetate copolymer saponified product; a polyvinyl chloride resin such as polyvinyl chloride; or a polyvinylidene chloride resin such as polyvinylidene chloride. The thermoplastic resin may be used alone or in combination of two or more types.

[0014] From the viewpoint of excellent handling properties, the thermoplastic resin is preferably a polyvinyl chloride resin, a polyvinylidene chloride resin, a polylactic acid resin, or a polyolefin resin, and more preferably a polyvinyl chloride resin, a polyvinylidene chloride resin, a polylactic acid resin, or a polyethylene resin.

[0015] From the viewpoint of excellent moldability, heat resistance, and fluidity of the wrap film, the polyvinyl chloride resin is preferably a polyvinyl chloride resin with an average degree of polymerization of 700 to 1300. In this specification, the average degree of polymerization refers to the average degree of polymerization measured in accordance with JIS K6720-2.

[0016] Polyvinyl chloride resins may be vinyl chloride homopolymers (polyvinyl chloride resins) from the viewpoint of excellent mechanical properties, or they may be copolymers of vinyl chloride and other monomers copolymerizable thereto for the purpose of imparting other properties. The copolymers may be graft copolymers, block copolymers, or random copolymers. Examples of other monomers include olefins such as ethylene, propylene, and butene; vinyl esters of saturated acids such as vinyl acetate and vinyl laurate; alkyl esters of unsaturated acids such as methyl acrylate and methyl methacrylate; alkyl vinyl ethers such as lauryl vinyl ether; aromatic vinyl compounds such as styrene and methylstyrene; unsaturated dicarboxylic acids such as maleic acid; acrylonitrile; and vinylidene fluoride.

[0017] When the polyvinyl chloride resin is a copolymer, the content of vinyl chloride units in the copolymer may be 10% by mass or more on a basis of the total amount of monomer units, and from the viewpoint of excellent mechanical properties, it is preferably 30% by mass or more, more preferably 50% by mass or more. The upper limit of the content of vinyl chloride units in the copolymer is not particularly limited, and for example, it may be 99% by mass or less on a basis of the total amount of monomer units.

[0018] The polyvinyl chloride resin may be, for example, a polymer blend with a three-dimensional polymer such as acrylonitrile-butadiene-styrene, a post-treated product with alcohol, or a post-treated product with a chlorine-containing compound. In these cases, the content of vinyl chloride units in the polyvinyl chloride resin may be 10% by mass or more based on the total amount of monomer units.

[0019] The polyvinylidene chloride-based resin may be a vinylidene chloride homopolymer (polyvinylidene chloride resin), or may be, for example, a copolymer containing vinylidene chloride and other monomers copolymerizable with vinylidene chloride as monomer units. The other monomers may be vinyl chloride, an acrylate of acrylic acid and an alcohol having 1 to 8 carbon atoms, a methacrylate of methacrylic acid and an alcohol having 1 to 8 carbon atoms, a vinyl ester of an aliphatic carboxylic acid, an unsaturated aliphatic carboxylic acid, an olefin, a vinyl ether, etc. Note that a copolymer of vinylidene chloride and vinyl chloride shall belong to the polyvinylidene chloride-based resin.

[0020] From the viewpoints of the moldability and heat resistance of the wrap film, the content of the vinylidene chloride unit in the polyvinylidene chloride-based resin may be, for example, 60% by mass or more, 70% by mass or more, or 80% by mass or more based on the total amount of monomer units. The upper limit of the content of the vinylidene chloride unit in the polyvinylidene chloride-based resin is not particularly limited, and may be, for example, 99% by mass or less based on the total amount of monomer units. The content of the vinylidene chloride unit can be measured by a nuclear magnetic resonance (NMR) apparatus.

[0021] The weight average molecular weight (Mw) of the polyvinylidene chloride-based resin may be, for example, 40,000 or more, 60,000 or more, or 80,000 or more, and may be 180,000 or less, 160,000 or less, or 140,000 or less, and may be 40,000 to 180,000, 60,000 to 160,000, or 80,000 to 140,000. The Mw of the polyvinylidene chloride-based resin can be measured by the GPC method using polystyrene with a known molecular weight as a standard substance.

[0022] The conditions of the GPC method used for measuring the Mw of the polyvinylidene chloride-based resin are as follows. Waters Gel Chromatograph Alliance GPC2000 type is used as the measuring apparatus. A solution of the polyvinylidene chloride-based resin dissolved in tetrahydrofuran to a concentration of 0.5% by mass is used as the sample. Columns: TSKgel GMHHR-H(S)HT 30cm x 2, TSKgel GMH6-HTL 30cm x 2 (manufactured by Tosoh Corporation) Mobile phase: tetrahydrofuran Detector: Differential refractometer Flow rate: 1.0mL / min Column temperature: 20℃ Injection volume: 500μL

[0023] Polyolefin resins may be, for example, polyethylene resins. Polyethylene resins may be copolymers using low-density polyethylene, linear low-density polyethylene, linear ultra-low-density polyethylene, medium-density polyethylene, high-density polyethylene, or ethylene as monomer units. Specifically, polyethylene resins may be copolymers of ethylene with one or more monomers selected from α-olefins having 3 to 10 carbon atoms such as propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, and 1-octene, vinyl esters such as vinyl acetate and vinyl propionate, unsaturated carboxylic acid esters such as methyl acrylate, ethyl acrylate, methyl methacrylate, and ethyl methacrylate, and unsaturated compounds such as conjugated dienes and unconjugated dienes. The ethylene unit content in polyethylene resins may be 50% by mass or more based on the total amount of monomer units.

[0024] From the viewpoint of excellent productivity, the thermoplastic resin content may be 60% by mass or more, 70% by mass or more, or 75% by mass or more based on the total amount of wrap film, and may also be 90% by mass or less, 85% by mass or less, or 80% by mass or less.

[0025] (Silver-containing additive) The silver-containing additive includes at least one selected from the group consisting of silver-based antibacterial agents and silver-based antiviral agents.

[0026] Silver-based antibacterial agents are antibacterial agents containing metallic silver, silver ions, or silver compounds. For example, a silver-based antibacterial agent may be an antibacterial agent in which a silver compound, silver complex salt, or silver ions are supported on an inorganic compound having a porous structure. Examples of such silver-based antibacterial agents include zeolite-silver-based antibacterial agents, glass-silver-based antibacterial agents, calcium phosphate-silver-based antibacterial agents, zirconium phosphate-silver-based antibacterial agents, and silicate-silver-based antibacterial agents.

[0027] Zeolite-silver-based antibacterial agents can be obtained, for example, by adding an aqueous silver nitrate solution to an aqueous suspension of type A synthetic zeolite, substituting a certain amount of silver ions at the Na positions in the crystal structure by an ion exchange reaction, drying, and then calcining. Zeolite-silver-based antibacterial agents are available from Shinanen Zeomic Co., Ltd. as "Zeomic" (e.g., "Zeomic AJ10D").

[0028] Glass-silver-based antibacterial agents can be obtained, for example, by supporting silver on silicate glass. Glass-silver-based antibacterial agents are available as "Ion Pure" manufactured by Ishizuka Glass Co., Ltd., etc.

[0029] Calcium phosphate-silver-based antibacterial agents are obtained, for example, by mixing an aqueous suspension of calcium phosphate, hydroxyapatite, calcium silicate, etc., with a silver nitrate solution, and supporting metallic silver or silver ions on calcium phosphate. Calcium phosphate-silver-based antibacterial agents are available as "Silver Ace" manufactured by Taihei Chemical Industry Co., Ltd., etc.

[0030] Zirconium phosphate-silver-based antimicrobial agents can be obtained, for example, by replacing lithium in crystalline lithium zirconium phosphate obtained by hydrothermal synthesis with protons by acid treatment, further replacing the protons with silver ions, and then drying and calcining. Zirconium phosphate-silver-based antimicrobial agents are available from Toagosei Co., Ltd. as "Novaron AG300," "Novaron AG1100," "Novaron AGZ330," "Novaron AGT330," etc.

[0031] Silicate-silver-based antimicrobial agents can be obtained, for example, by supporting silver ions on magnesium aluminometasilicate, followed by drying and calcination. Silicate-silver-based antimicrobial agents are available as "AIS-NAZ320" manufactured by JGC Catalysts & Chemicals Co., Ltd.

[0032] Silver-based antiviral agents are antiviral agents containing metallic silver, silver ions, or silver compounds. For example, a silver-based antiviral agent may be an antiviral agent in which a silver compound, silver complex salt, or silver ions are supported on an inorganic compound having a porous structure. Examples of such silver-based antiviral agents include zeolite-silver-based antiviral agents, glass-silver-based antiviral agents, calcium phosphate-silver-based antiviral agents, zirconium phosphate-silver-based antiviral agents, and silicate-silver-based antiviral agents. Silver-based antiviral agents are available as products such as "Novaron IV1000" manufactured by Toagosei Co., Ltd.

[0033] The silver-containing additive may be, for example, particles with an average particle size of 0.1 to 2 μm, 0.2 to 1.5 μm, or 0.5 to 1.2 μm.

[0034] From the viewpoint of further improving the antiviral properties of the wrap film, the content of the silver-containing additive is preferably 0.01% by mass or more, 0.02% by mass or more, or 0.03% by mass or more, based on the total amount of the wrap film, and from the viewpoint of further improving the transparency of the wrap film, it is preferably 1.0% by mass or less, 0.8% by mass or less, or 0.5% by mass or less.

[0035] (Glycerin-based anti-fogging agent) Glycerin-based anti-fogging agents contain polyglycerin fatty acid esters having an ester structure derived from fatty acids with 8 to 22 carbon atoms, from the viewpoint of achieving both antiviral properties and transparency of the wrap film. If the number of carbon atoms in the fatty acids constituting the polyglycerin fatty acid ester is less than 8 or more than 22, the antiviral properties of the wrap film tend to decrease. The number of carbon atoms in the fatty acids may be 10 or more, 12 or more, 20 or less, or 18 or less.

[0036] The fatty acids may be saturated or unsaturated fatty acids. Examples of saturated fatty acids include caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, and stearic acid. Examples of unsaturated fatty acids include monounsaturated fatty acids such as myristoleic acid, palmitoic acid, sapienic acid, oleic acid, and eicosenoic acid; diunsaturated fatty acids such as linoleic acid, eicosadienoic acid, and docosadenoic acid; triunsaturated fatty acids such as alpha-linolenic acid, gamma-linolenic acid, and pinolenic acid; and tetraunsaturated fatty acids such as arachidonic acid.

[0037] Glycerin-based anti-fogging agents may contain polyglycerin fatty acid esters having the structure represented by the following formula (1), from the viewpoint of achieving both antiviral properties and transparency of the wrap film. In the formula, R represents an aliphatic hydrocarbon group having 7 to 21 carbon atoms, and n represents a number from 1 to 4. The aliphatic hydrocarbon group is a group derived from the fatty acids mentioned above. The number of carbon atoms in the aliphatic hydrocarbon group may be 9 or more or 11 or more, or 19 or less or 17 or less. R may be a saturated aliphatic hydrocarbon group having 7 to 13 carbon atoms, or an unsaturated aliphatic hydrocarbon group having 8 to 21 carbon atoms. [ka]

[0038] Examples of polyglycerol fatty acid esters include diglycerol monocaprylate, diglycerol monocaprate, diglycerol monolaurate, diglycerol monomyristylate, diglycerol monomyristate, diglycerol monopalmitate, diglycerol monostearate, diglycerol monooleate, diglycerol monolinoleate, diglycerol monoelucate, and other diglycerol fatty acid esters; triglycerol monocaprylate, triglycerol monocaprate, triglycerol monolaurate, triglycerol monomyristylate, triglycerol monooleate, triglycerol monolinoleate, and triglycerol monoelucate. Examples include triglycerin fatty acid esters such as tetraglycerin monocaprylate, tetraglycerin monocaprate, tetraglycerin monolaurate, tetraglycerin monomyristylate, tetraglycerin monooleate, tetraglycerin monolinoleate, and tetraglycerin monoeluate; and pentagricerin fatty acid esters such as pentagricerin monocaprylate, pentagricerin monocaprate, pentagricerin monolaurate, pentagricerin monomyristylate, pentagricerin monooleate, pentagricerin monolinoleate, and pentagricerin monoeluate.

[0039] From the viewpoint of further improving the antiviral properties of the wrap film, the polyglycerin fatty acid ester may include at least one selected from diglycerin monolaurate, triglycerin monolaurate, tetraglycerin monolaurate, and pentaglicerin monolaurate.

[0040] The polyglycerin fatty acid ester content may be 0.1% by mass or more, 0.2% by mass or more, or 0.3% by mass or more on a total basis of the wrap film, from the viewpoint of further improving the antiviral properties of the wrap film, and may be 2.0% by mass or less, 1.5% by mass or less, or 1.0% by mass or less, from the viewpoint of further improving the transparency of the wrap film. The polyglycerin fatty acid ester content in the wrap film may be 0.1 to 2.0% by mass, 0.2 to 1.5% by mass, or 0.3 to 1.0% by mass.

[0041] The glycerin-based anti-fogging agent may further contain monoglycerin fatty acid esters or sorbitan fatty acid esters. Examples of monoglycerin fatty acid esters include monoglycerin laurate, monoglycerin myristate, monoglycerin palmitate, monoglycerin stearate, monoglycerin oleate, and monoglycerin linoleate. Examples of sorbitan fatty acid esters include sorbitan laurate and sorbitan stearate.

[0042] The total amount of glycerin-based antifogging agent may be 0.1% by mass or more, 0.3% by mass or more, or 0.5% by mass or more based on the total amount of the wrap film, from the viewpoint of the adhesiveness of the wrap film, and may be 2.5% by mass or less, 2.0% by mass or less, or 1.5% by mass or less, from the viewpoint of the dimensional stability and pullability of the wrap film.

[0043] (Coloring agent) The wrap film may further contain a coloring agent. Examples of coloring agents include blue coloring agents, red coloring agents, yellow coloring agents, green coloring agents, and purple coloring agents. The coloring agent may include at least one selected from the group consisting of these coloring agents.

[0044] The blue coloring agent is, for example, a coloring agent whose maximum absorption wavelength in the visible light region (wavelength: 380 to 750 nm) is located at 600 to 750 nm. The absorbance of the blue coloring agent at the maximum absorption wavelength in the visible light region is preferably at least twice, more preferably at least three times, the absorbance at a wavelength of 470 nm. Specifically, the blue coloring agent may be copper phthalocyanine (copper phthalocyanine blue), iron(III) hexacyanoferrate(II), a mixture of cobalt oxide and aluminum oxide, indigo, or ultramarine. From the viewpoint of further improving strength, dispersibility, and solvent resistance, the blue coloring agent is preferably a blue pigment.

[0045] The red coloring agent is, for example, a coloring agent whose maximum absorption wavelength in the visible light region (wavelength: 380 to 750 nm) is located at 500 to 599 nm. From the viewpoint of excellent visibility, the absorbance of the red coloring agent at the maximum absorption wavelength in the visible light region is preferably at least twice, more preferably at least three times, the absorbance at a wavelength of 650 nm.Specifically, the red colorants include quinacridone red, quinacridone scarlet, dimethylquinacridone, a mixture of 4-nitroaniline and 2-naphthol, a mixture of 2-nitro-4-toluidine and 2-naphthol, a mixture of 2-nitro-p-toluidine and 3-oxy-3'-nitronaphthalanilide, a mixture of o-anisidine and 2-naphthol, a mixture of 2,4,5-trichloroaniline and 3-oxy-2-naphtho-o-toluidine, and a mixture of 4-chloro-o-toluidine and 4'-chloro-3-hydroxy-2-naphtho-o-toluidine. Mixture with iodide, mixture of 2,5-dichloroaniline and 3-oxy-2-naphtho-p-toluidide, mixture of 2,5-dichloroaniline and 3-oxy-2-naphtho-o-anisidide, mixture of N,N'-diethyl-4-methoxymethanylamide and 5'-chloro-3-hydroxy-2',4'-dimethoxy-2-naphthoanilide, mixture of 4-nitro-o-anisidine and 3-oxy-N-1-naphthyl-2-naphthamide, mixture of 1-naphthylamine and 1-naphthol-5-sulfonic acid (calcium salt), 2-amino A mixture of -naphthalene-1-sulfonic acid and 2-naphthol (calcium salt), a mixture of 6-amino-m-toluenesulfonic acid and 3-oxy-2-naphthoic acid (calcium salt), a mixture of 2-amino-5-chloro-p-toluenesulfonic acid and 3-oxy-2-naphthoic acid (calcium salt), a mixture of 6-amino-4-chloro-m-toluenesulfonic acid and 3-oxy-2-naphthoic acid (calcium salt), a mixture of 2-aminonaphthalene-1-sulfonic acid and 3-oxy-2-naphthoic acid (calcium salt), 3,3'-dichlorobe This may include a mixture of diangidine and 3-carboxy-1-phenyl-5-pyrazolone, a mixture of o-dianisidine and 3-methyl-1-p-tolyl-5-pyrazolone, 1,2'-dioxyanthraquinone (calcium lake, iron lake, aluminum lake), 4,4'-dimethyl-6,6'-dichloro-2,2'-bisthionaphthene indigo, 4,4'-dimethyl-6,5',7'-trichloro-2,2'-bisthionaphthene indigo, a mixture of naphthionic acid and R acid (aluminum salt), erythrosine (aluminum salt), etc.The red coloring agent is preferably a red pigment, from the viewpoint of further improving strength, dispersibility, and solvent resistance.

[0046] The yellow coloring agent is, for example, a coloring agent whose maximum absorption wavelength in the visible light region (wavelength: 380 to 750 nm) is between 380 and 499 nm. From the viewpoint of excellent visibility, the absorbance of the yellow coloring agent at the maximum absorption wavelength in the visible light region is preferably at least twice, more preferably at least three times, the absorbance at a wavelength of 600 nm. Specifically, the yellow colorants are a mixture of o-nitroaniline and acetoacetanilide, a mixture of p-nitroaniline and acetoacetanilide, a mixture of 4-chloro-2-nitroaniline and acetoacetanilide, a mixture of o-nitro-p-toluidine and acetoacetanilide, a mixture of p-chloro-o-nitroaniline and o-chloro-acetoacetanilide, a mixture of 4-chloro-2-nitroaniline and acetoacet-m-xylidide, a mixture of sulfanilic acid and 3-carboxy-1-(p-sulfophenyl)-5-pyrazolone, a mixture of sulfanilic acid and 3-carboxy-1-(p-sulfophenyl)-5-pyrazolone (aluminum lake), a mixture of 3,3'-dichlorobenzidine and acetoacet-o-toluidine, and a mixture of 3,3'-dichlorobenzidine and acetoacet-p-toluidine This may include mixtures with zide, mixtures of 3,3'-dichlorobenzidine and acetoaceto-m-xylidide, mixtures of 1-amino-5-benzamide-anthraquinone and oxyral chloride, N,N-bis-(1-anthraquinolyl)-isophthalicamide, mixtures of 3,3'-dichlorobenzidine and 4-chloro-2,5-dimethoxyacetoacetanilide, mixtures of sulfanilic acid and sodium 2-naphthol-6-sulfonate, mixtures of 3,3'-dichlorobenzidine and 3-methyl-1-phenyl-5-pyrazolone, mixtures of o-dianisidine and acetoacetanilide, 4,11-bis(benzoylamino)-16H-dinaphtho[2,3-a:2',3'-i]carbazole-5,10,15,17-tetraone, mixtures of naphthalenetetracarboxylic acid and 1,2-diaminobenzene, etc. The yellow coloring agent is preferably a yellow pigment, from the viewpoint of further improving strength, dispersibility, and solvent resistance.

[0047] The green coloring agent may be an α-nitroso-β-naphthol iron complex, a 4-nitrobenzeneazo-2-naphthol copper complex, an octachlorocopper phthalocyanine, a polychlorocopper phthalocyanine, or the like.

[0048] The purple coloring agent may be 6,15-dibromo-isobiolancerone, 5,5'-dichloro-4,4,7,7'-tetramethyl-2,2'-bis(thionaphthene indigo), dioxazine violet, quinacridone violet, etc.

[0049] The coloring agent content may be 0.5% by mass or more, or 0.6% by mass or more, and may be 2.0% by mass or less, or 1.9% by mass or less, based on the total amount of the wrap film.

[0050] (Other ingredients) The wrap film may further contain other components. Examples of other components include plasticizers, stabilizers (heat stabilizers or light stabilizers), lubricants, fillers, plate-out inhibitors, antioxidants, release agents, viscosity reducers, surfactants, fluorescent agents, surface treatment agents, crosslinking agents, processing aids, adhesives, antistatic agents, UV absorbers, and antiblocking agents. If the wrap film contains other components, the content of these other components (total content) may be, for example, 1% by mass or more and 30% by mass or less based on the total amount of the wrap film.

[0051] The wrap film preferably further contains a plasticizer. The plasticizer may be, for example, an adipic acid ester, an epoxidized vegetable oil, etc.

[0052] The adipic acid ester may be, for example, a diester of adipic acid with a linear or branched aliphatic alcohol having 6 to 10 carbon atoms (adipic acid diester). The adipic acid ester may be, for example, dioctyl adipate, diisononyl adipate, etc.

[0053] Epoxy-modified vegetable oils may include, for example, epoxy-modified soybean oil, epoxy-modified linseed oil, epoxy-modified castor oil, epoxy-modified corn oil, epoxy-modified rapeseed oil, epoxy-modified safflower oil, epoxy-modified sunflower oil, epoxy-modified palm oil, epoxy-modified cottonseed oil, epoxy-modified olive oil, and the like.

[0054] The plasticizer content may be, for example, 15% by mass or more, or 20% by mass or more, or 35% by mass or less, or 30% by mass or less, based on the total amount of the wrap film.

[0055] The wrap film preferably further contains a stabilizer. The stabilizer may be, for example, a Ca / Zn-based stabilizer. A Ca / Zn stabilizer is a mixture of a fatty acid salt of calcium and a fatty acid salt of zinc. Examples of such fatty acids include behenic acid, stearic acid, lauric acid, oleic acid, palmitic acid, and ricinoleic acid.

[0056] The stabilizer content may be, for example, 0.1% by mass or more, or 0.5% by mass or more, or 5% by mass or less, or 3% by mass or less, based on the total amount of wrap film.

[0057] The wrap film may consist of only one layer containing a thermoplastic resin, a silver-containing additive, and a glycerin-based antifogging agent, or it may consist of multiple layers. If the wrap film consists of multiple layers, the thermoplastic resin, the silver-containing additive, and the glycerin-based antifogging agent may each be contained in any of the layers, they may be contained in the same layer, or they may be contained in different layers.

[0058] If the wrap film consists of multiple layers, it may, for example, comprise a first surface layer, an intermediate layer, and a second surface layer in that order. In this case, for example, the first and second surface layers may contain a thermoplastic resin, a silver-based antiviral agent, a glycerin-based antifogging agent, and other components added as needed, while the intermediate layer may contain a thermoplastic resin and other components added as needed. The wrap film may further comprise an adhesive layer containing, for example, an acid-modified polyolefin resin to improve adhesion between each layer, and may further comprise a heat-resistant layer containing a polyamide resin to improve the heat resistance of the wrap film.

[0059] The thickness of the wrap film may be preferably 10 μm or less, more preferably 9 μm or less, and even more preferably 8 μm or less, from the viewpoint of workability and strength, and may be preferably 4 μm or more, more preferably 5 μm or more, and even more preferably 6 μm or more, from the viewpoint of efficiently sealing food from the outside air.

[0060] The total light transmittance of the wrap film is preferably 75% or higher, more preferably 80% or higher, and may be, for example, 90% or lower, from the viewpoint of excellent visibility. The total light transmittance can be calculated by measuring the amount of incident light and the amount of total transmitted light in accordance with JIS K7361-1, and using the formula: Total light transmittance = (total transmitted light) / (incident light) × 100.

[0061] Wrap film is manufactured by, for example, mixing a thermoplastic resin, a silver-based antiviral agent, a glycerin-based antifogging agent, and optionally the aforementioned colorants and other components using a mixer such as a V-type blender, ribbon blender, Henschel mixer, or super mixer, and then kneading the mixture using a kneader such as a mixing roll, Banbury mixer, or kneader to obtain a composition, which is then manufactured by, for example, extrusion molding. Specifically, the composition is supplied to the hopper of an extruder and the desired wrap film is obtained by the inflation method, T-die method, or the like.

[0062] When a wrap film consists of multiple layers, the wrap film is obtained by melt-extruding the constituent raw materials of each layer into separate extruders and then co-extruding and laminating each layer using methods such as the inflation method or the T-die method. In this case, it is preferable to form the wrap film by rapidly cooling the molten material extruded from the T-die using a casting roll or the like.

[0063] The wrap film obtained in this manner may be subjected to heat treatments such as longitudinal stretching between heated rolls, various heat fixation methods, and aging, depending on the purpose of reducing the heat shrinkage rate, natural shrinkage rate, etc., and suppressing the occurrence of width shrinkage, etc. Furthermore, to improve antifogging, antistatic properties, adhesiveness, etc., it may be subjected to corona treatment, aging treatment, surface treatments such as printing and coating, surface processing, etc.

[0064] [Wrap film container] The wrap film is, for example, formed into a long roll and wound up, then further rewound (re-wound) into desired lengths such as 20m or 50m, and packed into a box to become the product. In other words, the wrap film in this embodiment may be in the form of wrap film wound around a core, or in the form of wrap film housed in a box.

[0065] Figure 1 is a perspective view showing a wrap film container according to one embodiment. As shown in Figure 1, the wrap film container 1 according to one embodiment comprises a wrap film 2, a core 3 around which the wrap film is wound, and a box body 4 that houses the wrap film 2 and the core 3. The box body 4 may be provided with a blade 5 for cutting the wrap film 2. The materials of the core 3 and the box body 4 are not particularly limited. From the viewpoint of making it easy to recognize the color of the wrap film from the outside, at least a part of the box body 4 is preferably transparent or has holes to the extent that it does not impair the function of the box, so that the inside can be seen from the outside.

[0066] Generally, "film" refers to a thin, flat product with an extremely small thickness relative to its length and width, and a maximum thickness that can be arbitrarily limited, which can be supplied in roll form (see Japanese Industrial Standard JIS K6900 if necessary), while "sheet" generally refers to a thin, flat product whose thickness is generally small relative to its length and width, according to the JIS definition. However, the boundary between sheet and film is not clear, and in this embodiment there is no need to distinguish between the two in terms of wording, so in this specification, the term "film" includes "sheet," and the term "sheet" includes "film." Furthermore, "film" is a concept that specifically includes wrap film among the above definitions. [Examples]

[0067] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

[0068] (1) Preparation of resin composition The following materials were added to a super mixer in the amounts (mass%) shown in Table 1. The material temperature was then raised from room temperature to 130°C while stirring, and the mixture was prepared to create the resin compositions of the examples and comparative examples. Thermoplastic resin a: Polyvinyl chloride resin Glycerin-based anti-fogging agent b1: Glycerin monooleate (manufactured by Riken Vitamin Co., Ltd., "XO-100") Glycerin-based anti-fogging agent b2: Diglycerin monolaurate (manufactured by Riken Vitamin Co., Ltd., "Poem DL-100") Silver-containing additive c1: Zirconium phosphate-silver-based antibacterial agent (manufactured by Toagosei Co., Ltd., "Novaron AG300") Silver-containing additive c2: Silver-based antiviral agent (manufactured by Toagosei Co., Ltd., "Novaron IV1000") Plasticizer d1: Diisononyl adipate Plasticizer d2: Epoxy soybean oil Stabilizer e: Ca / Zn-based stabilizer

[0069] (2) Preparation of plastic wrap A resin composition cooled to 70°C was extruded using a 40mm diameter single-screw extruder (L / D=20) equipped with a T-die (width 350mm, gap 0.4mm) at a temperature of 200°C to produce a wrap film with a thickness of 8.0 μm.

[0070] (3) Evaluation Table 1 shows the evaluation results of the resin composition and wrap film in each example and comparative example.

[0071] (thermal stability) The dynamic thermal stability of the resin compositions was evaluated by placing 60g of each resin composition into a Roller Mixer R60 attached to a Laboplast Mill (Toyo Seiki Seisakusho Co., Ltd., "4C150-01") and mixing at 210°C and 60rpm. The dynamic thermal stability time was defined as the time it took to reach 150% of the steady-state torque value. A longer dynamic thermal stability time indicates superior thermal stability. A: It took more than 20 minutes to reach 150% of the torque value. B: The time it took to reach 150% of the torque value was less than 20 minutes.

[0072] (Film forming property) The above-mentioned resin composition was extruded using a T-die extruder at a resin temperature of 200°C to form a wrap film, and the film-forming properties were evaluated by observing the appearance of the resulting wrap film. The evaluation criteria are as follows. A: A wrap film with nearly uniform thickness was obtained, and no burning occurred during 24-hour extrusion. B: There was slight unevenness in the thickness of the wrap film, and scorching occurred after 24 hours of extrusion.

[0073] (transparency) Transparency was evaluated by measuring the haze (cloudiness) of the wrap film using a haze meter (NDH 5000, manufactured by Nippon Denshoku Industries Co., Ltd.). After standard calibration using the NDH-5000 standard plate (cloudiness 11.35, H51-28491), the wrap film was attached to the haze jig without wrinkles, and the haze was measured. The same measurement was performed three times, changing the measurement location on the wrap film, and the average value of the haze was calculated. A: The average haze value of the wrap film was 2.0 or less. B: The average haze value of the wrap film was greater than 2.0.

[0074] (Antiviral) Antiviral activity was evaluated using influenza A virus in accordance with ISO 21702. Antiviral activity was calculated by measuring the viral infectivity titer of the wrap film. A: The antiviral activity value of the plastic wrap was 2.0 or higher. B: The antiviral activity value of the plastic wrap was less than 2.0.

[0075] [Table 1] [Explanation of Symbols]

[0076] 1...Wrap film container, 2...Wrap film, 3...Core, 4...Box, 5...Cutting edge.

Claims

1. It contains a thermoplastic resin, a silver-containing additive, and a glycerin-based anti-fogging agent. The silver-containing additive comprises at least one selected from the group consisting of silver-based antibacterial agents and silver-based antiviral agents. The aforementioned glycerin-based anti-fogging agent is a wrap film containing a polyglycerin fatty acid ester having an ester structure derived from a fatty acid with 12 carbon atoms, and a monoglycerin fatty acid ester. The polyglycerol fatty acid ester is at least one selected from diglycerol monolaurate, triglycerol monolaurate, tetraglycerol monolaurate, and pentaglicerol monolaurate. A wrap film in which the content of the polyglycerin fatty acid ester is 0.3 to 1.0% by mass based on the total amount of the wrap film.

2. The wrap film according to claim 1, further containing a coloring agent.

3. The wrap film according to claim 2, wherein the coloring agent comprises at least one selected from the group consisting of a blue coloring agent, a red coloring agent, a yellow coloring agent, a green coloring agent, and a purple coloring agent.

4. The wrap film according to any one of claims 1 to 3, wherein the thermoplastic resin comprises at least one selected from the group consisting of polyester resins, polyamide resins, polystyrene resins, polylactic acid resins, polyolefin resins, polyvinyl chloride resins, and polyvinylidene chloride resins.

5. A wrap film used for packaging food, according to any one of claims 1 to 4.

6. The core and A wrap film according to any one of claims 1 to 4, wound around the aforementioned core, A wrap film container comprising the aforementioned core and a box for housing the wrap film.

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