Wrap film and housing body for wrap film

Abstract

To obtain a wrap film excellent in productivity and cold resistance even when the biomass degree of the wrap film is made 10% or more by an additive derived from biomass.SOLUTION: A wrap film produced according to the present invention comprises: a thermoplastic resin; a biomass-derived glyceride represented by formula (1): [In the formula, R1, R2 and R3 are each independently a methyl group or an alkyl group having carbon atoms of 10 or more, at least one of R1, R2 and R3 is a methyl group, and at least one of R1, R2 and R3 is an alkyl group.]; and an epoxidized soybean oil.SELECTED DRAWING: None

Description

[Technical field]

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

[0002] Wrap films are widely used not only in homes, but also in hotels, restaurants, etc. In recent years, from the perspective of carbon neutrality, there has been a growing movement to replace petroleum-derived raw materials for wrap films with plant-derived (biomass) materials. One method of proving the use of biomass materials is the biomass mark certified by the Japan Organic Resources Association. For example, in order to obtain the biomass mark for wrap films made of polyvinyl chloride, it is necessary to achieve a biomass degree of 10% or more using only additives added to polyvinyl chloride. Against this background, for example, Patent Document 1 discloses a biomass plasticizer for polyvinyl chloride resins. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2023-94867 A Summary of the Invention [Problem to be solved by the invention]

[0004] According to the investigations of the present inventors, if a significant amount of biomass-derived additives (e.g., plasticizers) is used to increase the biomass content of a wrap film to 10% or more, the properties required of the wrap film may be impaired.

[0005] Therefore, one aspect of the present invention aims to obtain a wrap film that has excellent productivity and cold resistance, even when the biomass content of the wrap film is increased to 10% or more by using a biomass-derived additive. [Means for solving the problem]

[0006] The inventors have discovered that by combining a glyceride having a specific chemical structure with epoxidized soybean oil as a biomass-derived additive, a wrap film with excellent productivity and cold resistance can be obtained even when the biomass content of the wrap film is 10% or more.

[0007] The present invention includes the following aspects. [1] A thermoplastic resin; A biomass-derived glyceride represented by the following formula (1), [ka] [In the formula, R 1 , R 2 and R 3 are each independently a methyl group or an alkyl group having 10 or more carbon atoms; R 1 , R 2 and R 3 At least one of R is a methyl group. 1 , R 2 and R 3 At least one of the groups is an alkyl group. epoxidized soybean oil; A wrap film comprising: [2] The wrap film according to [1], wherein the biomass content of the wrap film is 10% or more. [3] The wrap film according to [1] or [2], wherein the thermoplastic resin is a polyvinyl chloride resin. [4] The wrap film according to any one of [1] to [3], having a glyceride content of 2% by mass or more and 17% by mass or less, based on the total mass of the wrap film. [5] The wrap film according to any one of [1] to [4], wherein the epoxidized soybean oil content is from 2% by mass to 12% by mass, based on the total mass of the wrap film. [6] A wrap film according to any one of [1] to [5], which is used for packaging food. [7] A wrap film container comprising: a core; the wrap film according to any one of [1] to [6] wound around the core; and a box for housing the core and the wrap film. Effect of the Invention

[0008] According to one aspect of the present invention, even when the biomass content of the wrap film is increased to 10% or more by using a biomass-derived additive, a wrap film with excellent productivity and cold resistance can be obtained. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a perspective view showing a wrap film container according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate. However, the present invention is not limited to the following embodiment.

[0011] One embodiment of the present invention is a wrap film containing a thermoplastic resin, a specific glyceride derived from biomass (described in detail below), and epoxidized soybean oil. This wrap film is a film for wrapping articles, and is particularly suitable for use in wrapping food.

[0012] Examples of thermoplastic resins include polyvinyl chloride resins such as polyvinyl chloride, polyvinylidene chloride resins such as polyvinylidene chloride, polyester resins such as polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate, polyamide resins such as 6-nylon, 6,6-nylon, and 12-nylon, polystyrene resins such as butadiene-styrene copolymer, acrylonitrile-styrene copolymer, polystyrene, styrene-butadiene-styrene copolymer, styrene-isoprene-styrene copolymer, and styrene-acrylic acid copolymer, polylactic acid resins such as poly-L-lactic acid, poly-D-lactic acid, and poly-DL-lactic acid, and polyolefin resins such as polyethylene, polypropylene, and saponified ethylene-vinyl acetate copolymer. Thermoplastic resins may be used alone or in combination of two or more.

[0013] The thermoplastic resin is preferably a polyvinyl chloride resin. The polyvinyl chloride resin may be polyvinyl chloride (vinyl chloride homopolymer) or a copolymer of vinyl chloride and another monomer copolymerizable therewith (vinyl chloride copolymer).

[0014] The copolymer may be a graft copolymer, a block copolymer or a random copolymer. Examples of other monomers include olefins such as ethylene, propylene, 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.

[0015] When the polyvinyl chloride resin is a copolymer, the content of vinyl chloride units in the copolymer may be 10 mass% or more, 30 mass% or more, or 50 mass% or more, or may be 99 mass% or less, based on the total amount of monomer units.

[0016] The average degree of polymerization of the polyvinyl chloride resin may be not less than 700 and not more than 1300. In this specification, the average degree of polymerization means the average degree of polymerization measured in accordance with JIS K6720-2.

[0017] The content of the thermoplastic resin may be 60% by mass or more, 70% by mass or more, or 75% by mass or more, and may be 90% by mass or less, 85% by mass or less, or 80% by mass or less, based on the total amount of the wrap film.

[0018] The biomass-derived glyceride contained in the wrap film is represented by the following formula (1). [ka] In the formula, R 1 , R 2 and R 3 are each independently a methyl group or an alkyl group having 10 or more carbon atoms.

[0019] R 1 , R 2 and R 3 At least one of R is a methyl group. 1 , R 2 and R 3 At least one of R is an alkyl group. 1 , R 2 and R 3 Two of the groups are methyl groups, and R 1 , R 2 and R 3 One of R may be an alkyl group. 1 , R 2 and R 3 One of them is a methyl group, and R 1 , R 2 and R 3 Two of R may be alkyl groups. 1 is a methyl group, and R 2 and R 3 is preferably an alkyl group.

[0020] R 1 , R 2 and R 3 The number of carbon atoms in the alkyl group represented by the formula (I) may be 11 or more or 12 or more, and may be 20 or less, 19 or less, 18 or less, 17 or less, 16 or less, 15 or less, 14 or less, 13 or less, or 12 or less, or may be 12. The alkyl group may be linear or branched, and is preferably linear.

[0021] The glyceride may be, for example, a glyceride derived from palm oil, a glyceride derived from palm kernel oil, a glyceride derived from coconut oil, etc., and is preferably a glyceride derived from palm oil.

[0022] The biomass degree of the above glyceride may be 60% or more, 70% or more, or 80% or more. The biomass degree (%) in this specification is calculated by the following formula: Mass of biomass in the object / total mass of the object x 100 In addition, when the target contains a solvent, "mass of biomass in the target" and "total mass of the target" both mean the dry mass after removing the solvent. In addition, "mass of biomass in the target" is measured according to ISO 16620-4:2016.

[0023] The content of the above glyceride may be 2% by mass or more, 3% by mass or more, or 4% by mass or more, and may be 17% by mass or less, 16% by mass or less, or 15% by mass or less, based on the total amount of the wrap film.

[0024] The epoxidized soybean oil contained in the wrap film may be a known epoxidized soybean oil (derived from biomass). The biomass content of the epoxidized soybean oil may be 70% or more, 80% or more, or 90% or more.

[0025] The content of the above epoxidized soybean oil may be 2% by mass or more, 3% by mass or more, or 4% by mass or more, and may be 12% by mass or less, 11% by mass or less, or 10% by mass or less, based on the total amount of the wrap film.

[0026] The wrap film may further contain other additives that are not derived from biomass. Examples of other additives include plasticizers, stabilizers, anti-fogging agents, colorants, lubricants, fillers, plate-out inhibitors, antioxidants, release agents, viscosity reducers, surfactants, fluorescent agents, surface treatment agents, crosslinking agents, processing aids, adhesives, antistatic agents, ultraviolet absorbers, and antiblocking agents. The content (total content) of such additives may be, for example, 1% by mass or more and 30% by mass or less based on the total amount of the wrap film.

[0027] The wrap film may further preferably contain a plasticizer not derived from biomass. Examples of such plasticizers include adipic acid esters. The adipic acid esters may be, for example, diesters (adipic acid diesters) of adipic acid and linear or branched aliphatic alcohols having 6 to 10 carbon atoms. The adipic acid esters may be, for example, dioctyl adipate, diisononyl adipate, etc. The content of the plasticizer may be, for example, 3% by mass or more, 4% by mass or more, or 5% by mass or more, and 11% by mass or less, 10% by mass or less, or 9% by mass or less, based on the total amount of the wrap film.

[0028] The wrap film may preferably further contain a stabilizer derived from biomass (heat stabilizer or light stabilizer). The stabilizer may be, for example, a Ca / Zn stabilizer. The Ca / Zn stabilizer may be a mixture of a fatty acid salt of calcium and a fatty acid salt of zinc. Examples of the fatty acid include behenic acid, stearic acid, lauric acid, oleic acid, palmitic acid, and ricinoleic acid. The content of the stabilizer may be 0.1% by mass or more, 0.5% by mass or more, or 0.8% by mass or more, based on the total amount of the wrap film, and may be 2.0% by mass or less, 1.5% by mass or less, or 1.2% by mass or less.

[0029] The wrap film may preferably further contain an anti-fogging agent not derived from biomass. Such an anti-fogging agent may further contain, for example, a glycerin-based anti-fogging agent. The glycerin-based anti-fogging agent may contain a polyglycerin fatty acid ester having an ester structure derived from glycerin and a fatty acid having 8 to 22 carbon atoms. The content of the anti-fogging agent may be 0.1% by mass or more, 0.5% by mass or more, or 0.8% by mass or more, and may be 2.0% by mass or less, 1.5% by mass or less, or 1.2% by mass or less, based on the total amount of the wrap film.

[0030] The biomass degree of the wrap film may be 10% or more, 11% or more, 12% or more, 13% or more, 14% or more, or 15% or more, or may be 20% or less. Even when the wrap film according to this embodiment has such a high biomass degree, the wrap film exhibits excellent productivity and cold resistance due to the glyceride and epoxidized soybean oil.

[0031] The wrap film may consist of only one layer containing a thermoplastic resin, the above-mentioned glyceride, and the above-mentioned epoxidized soybean oil (and other additives used as necessary). The thickness of the wrap film may be 4 μm or more, 5 μm or more, or 6 μm or more, and may be 11 μm or less, 10 μm or less, or 9 μm or less.

[0032] The total light transmittance of the wrap film may be 75% or more, or 80% or more, and may be 90% or less. In this specification, the total light transmittance is calculated according to JIS K7361-1 by measuring the amount of incident light and the total amount of transmitted light of the wrap film, and the total light transmittance (%)=(total amount of transmitted light) / (amount of incident light)×100.

[0033] The wrap film can be produced, for example, as follows. First, the thermoplastic resin, the glyceride, the epoxidized soybean oil, and, if necessary, the other additives are mixed using a mixer such as a V-type blender, a ribbon blender, a Henschel mixer, or a super mixer. Next, the resulting mixture is kneaded using a kneader such as a mixing roll, a Banbury mixer, or a kneader, if necessary, to obtain a composition. Furthermore, the resulting composition is extrusion molded to obtain a wrap film. More specifically, the composition is fed into the hopper of an extruder, and the desired wrap film is obtained by using an inflation method, a T-die method, or the like.

[0034] When the wrap film is made up of multiple layers, the wrap film can be obtained by feeding the constituent materials of each layer into separate extruders, melt extruding them, and co-extruding and laminating the layers by an inflation method, a T-die method, etc. In this case, it is preferable to form the wrap film by taking up the molten material extruded from the T-die as it is while quenching it with a casting roll or the like.

[0035] The wrap film thus obtained may be subjected to heat treatments such as longitudinal stretching between heated rolls, various types of heat fixing, aging, etc., depending on the purpose of reducing the thermal shrinkage rate and natural shrinkage rate, etc., and suppressing the occurrence of width shrinkage, and corona treatment, aging treatment, surface treatments such as printing and coating, surface finishing, etc. may be performed for the purpose of improving anti-fogging properties, antistatic properties, adhesion, etc.

[0036] The wrap film is, for example, formed into a long shape and wound up, and then rewound (rolled) at desired lengths of 20 m, 50 m, etc., and packed into a box to form a product. That is, the wrap film may be in the form of a wrap film wound around a core, or may be in the form of a wrap film contained in a box.

[0037] Fig. 1 is a perspective view showing a wrap film container according to one embodiment. As shown in Fig. 1, the wrap film container 1 according to one embodiment includes a wrap film 2, a core 3 around which the wrap film is wound, and a box 4 that contains the wrap film 2 and the core 3. The box 4 may be provided with a blade 5 for cutting the wrap film 2. The material of the core 3 and the box 4 is 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 4 is preferably transparent or has a hole therein to the extent that the function as a box is not impaired, so that the inside can be seen from the outside.

[0038] In addition, a "film" generally refers to a thin, flat product that is extremely thin compared to its length and width, has an arbitrarily limited maximum thickness, and can be supplied in the form of a roll (if necessary, the Japanese Industrial Standard JIS K6900 can be referred to), and a "sheet" generally refers to a product that is thin, generally small in thickness compared to its length and width, and is flat, as defined in the JIS. However, the boundary between a sheet and a film is unclear, and there is no need to distinguish between the two in the present embodiment, so in this specification, the term "film" includes "sheet," and the term "sheet" includes "film." In addition, "film" is a concept that includes wrap film, among the above definitions. EXAMPLES

[0039] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

[0040] The following materials were charged into a super mixer in the amounts (mass%) shown in Table 1, and then the temperature of the materials was raised from room temperature to 130°C while stirring, and then the materials were mixed to prepare each resin composition of the examples and comparative examples. Thermoplastic resin: Polyvinyl chloride resin (manufactured by Taiyo PVC Co., Ltd., "TH-1000") Biomass-derived glyceride represented by the following formula (1) (biomass content: 74%) [ka] Epoxidized soybean oil (ADEKA Corporation, "O-130B", biomass content: 92%) Non-biomass-derived plasticizers (diisononyl adipate, DIC Corporation, "W-242") Stabilizer (ADEKA Corporation, "SC-308E") Anti-fogging agent (Riken Vitamin Co., Ltd., "XO-100")

[0041] (Productivity Evaluation) The above resin composition was cooled to 70°C, and then extruded at a temperature of 200°C using a 40 mm diameter single screw extruder (L / D=20) equipped with a T-die (width 350 mm, gap 0.4 mm) to produce a wrap film with a thickness of 8.0 μm. The number of production troubles (holes, film breaks, etc.) that occurred per day were counted and productivity was evaluated according to the following criteria. "A" or "B" indicates excellent productivity. The results are shown in Table 1. A: 0 to 2 times per day B: 3~4 times / day C: 5 or more times / day

[0042] (Evaluation of cold resistance) The obtained wrap film was cut into a piece 4 cm wide and 11 cm long in the MD direction, and then folded in four to prepare a 1 cm wide test piece. The test piece was left to stand in a 0°C environment for 10 minutes, and then the elastic modulus was measured in a 0°C environment using a Strograph (Shimadzu Corporation, "EZ-S") The lower the elastic modulus, the better the cold resistance. The cold resistance was evaluated according to the measured elastic modulus using the following criteria. "A" or "B" indicates excellent cold resistance. The results are shown in Table 1. A: Less than 900Mpa B: 900Mpa or more and less than 1000Mpa C:1000Mpa or more

[0043] [Table 1] [Explanation of symbols]

[0044] 1...wrap film container, 2...wrap film, 3...core, 4...box body, 5...blade portion.

Claims

1. A thermoplastic resin; A biomass-derived glyceride represented by the following formula (1), 【Chemistry 1】 [In the formula, R １ , R ２ and R ３ are each independently a methyl group or an alkyl group having 10 or more carbon atoms; R １ , R ２ and R ３ At least one of R １ , R ２ and R ３ At least one of the above is the alkyl group. epoxidized soybean oil; A wrap film comprising:

2. The wrap film according to claim 1 , wherein the wrap film has a biomass content of 10% or more.

3. The wrap film according to claim 1 , wherein the thermoplastic resin is a polyvinyl chloride resin.

4. 2. The wrap film according to claim 1, wherein the glyceride content is from 2% by mass to 17% by mass, based on the total mass of the wrap film.

5. The wrap film according to claim 1 , wherein the content of the epoxidized soybean oil is from 2% by mass to 12% by mass, based on the total amount of the wrap film.

6. The wrap film according to claim 1, which is used for packaging food.

7. A core; The wrap film according to any one of claims 1 to 6, which is wound around the core; A box that accommodates the core and the wrap film; A wrap film container comprising:

Images