Packaging film, packaging material, packaging bag, and package including same

Abstract

To provide a packaging film or the like capable of imparting superiority in slippage for an oil-in-water dispersion type content by heat treatment.SOLUTION: A packaging film comprises a first resin layer containing resin and a porous filler. The resin contains a polyolefin and a silylated polyolefin, and the porous filler has an oil absorption of 100 to 380 mL / 100 g.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a film for packaging material, and a packaging material and a package including the same. [Background technology]

[0002] Conventionally, packages that enclose oil-in-water dispersion-type contents such as curry have been known. Problems that have been pointed out about such packages include the fact that when the package is opened and the contents are discharged, the contents cannot be used up completely, resulting in waste, the contents sticking to the surface, and the work of discharging the contents being time-consuming.

[0003] For this reason, there is a demand for packages that allow the contents to easily slide out when opened, i.e., that impart excellent sliding properties to the contents.

[0004] For example, Patent Document 1 proposes that a package using a packaging sheet containing polyolefin particles having an average particle size D50 of 10 to 50 μm and a melting point of 100 to 180° C. and having a heat seal layer with a surface roughness Ra of 1.00 to 7.00 μm makes the surface of the contents less likely to adhere to the package, making it easier to remove the contents from the package. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2018 / 003978 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the package described in Patent Document 1 has the following problems. That is, the package described in Patent Document 1 above has room for improvement in terms of ease of discharging the contents when opened, that is, in terms of slipping off resistance.

[0007] The present disclosure has been made in consideration of the above circumstances, and aims to provide a film for packaging material that can impart excellent sliding properties to oil-in-water dispersion-type contents through heat treatment, and a packaging material, packaging bag, and packaging body including the same.

[0008] In the present disclosure, the oil-in-water dispersion type content refers to a content that contains water and lipids, and the water content is greater than the lipid content. The term "lipid" is a concept that encompasses oils that are liquid at 20°C (room temperature) and fats that are solid at 20°C. Hereinafter, the oils contained in the oil-in-water dispersion type content and the fats that become liquid by the heat treatment applied to the packaging film according to the present disclosure will be collectively referred to as "oil content". [Means for solving the problem]

[0009] In order to solve the above problems, the present disclosure provides a film for packaging material, comprising a first resin layer containing a resin and a porous filler, the resin containing a polyolefin and a silylated polyolefin, and the porous filler having an oil absorption of 100 to 380 mL / 100 g.

[0010] This packaging film can be provided with excellent sliding properties for oil-in-water dispersion type contents by heat treatment.

[0011] The reason why the packaging film of the present disclosure provides the above-mentioned effects is presumably as follows.

[0012] That is, the polyolefin contained in the resin in the first resin layer is capable of absorbing oil under the temperature conditions of retort treatment or boiling treatment. For this reason, for example, when the film for packaging material is used as a packaging material for a package containing oil-in-water dispersion-type contents, and the oil-in-water dispersion-type contents are brought into contact with the surface of the first resin layer of the film for packaging material and subjected to a heat treatment such as retort treatment or boiling treatment, a part of the oil in the contents is absorbed into the first resin layer, and the lipophilicity of the first resin layer is improved. On the other hand, since the first resin layer contains a porous filler, unevenness is formed on the surface of the first resin layer, making it possible to increase the contact area between the first resin layer and the oil-in-water dispersion-type contents, that is, the passage area of ​​the oil. In addition, since the porous filler has an oil absorption amount within a specific range, it is possible to effectively adsorb oil, and the adsorption of the oil promotes the absorption of the oil contained in the oil-in-water dispersion-type contents into the first resin layer, and the moderate oil absorption makes it possible to easily form an oil film on the surface of the first resin layer. As a result, an oil film is stably formed between the surface of the first resin layer and the contents. Therefore, when the package is opened and the contents are dropped, the contents whose surface layer is composed of water are easily slippery against the oil film having water repellency. However, friction still occurs between the contents and the oil film. Therefore, if the friction between the first resin layer and the oil film is large and the oil film is difficult to slide off against the first resin layer, the contents are difficult to slide off. In this respect, the film for packaging material of the present disclosure contains a silylated polyolefin in the resin in the first resin layer, which reduces the friction between the first resin layer and the oil film, making it easier for the oil film to slide off against the first resin layer, and the oil-in-water dispersion type contents easily slide off together with the oil film. It is thus speculated that the above effect can be obtained by the film for packaging material of the present disclosure.

[0013] In the first resin layer, the amount of the silylated polyolefin added is preferably 0.1 to 20% by mass based on 100% by mass of the polyolefin.

[0014] In this case, the friction between the first resin layer and the oil film can be effectively reduced, and the oil film can be easily slid down the first resin layer, compared to when the amount of silylated polyolefin added in the first resin layer is less than 0.1% by mass based on 100% by mass of polyolefin. Also, the oil film can be more easily formed on the surface of the first resin layer by heat treatment, compared to when the amount of silylated polyolefin added in the first resin layer is more than 20% by mass based on 100% by mass of polyolefin.

[0015] In the above-mentioned packaging film, it is preferable that the polyolefin and the polyolefin portion of the silylated polyolefin are incompatible, and the first resin layer further contains a compatibilizer having a first compatible portion compatible with the polyolefin and a second compatible portion compatible with at least a portion of the silylated polyolefin. Here, "incompatible" means that when a polyolefin is blended with the polyolefin portion of a silylated polyolefin, the polyolefin portion does not disperse uniformly in the polyolefin, forming a sea-island structure.

[0016] In the case where the polyolefin and the polyolefin portion of the silylated polyolefin are incompatible, the first resin layer contains a compatibilizer, which allows the first compatible portion of the compatibilizer to be compatible with the polyolefin and the second compatible portion of the compatibilizer to be compatible with at least a part of the silylated polyolefin. This further suppresses the aggregation of the silylated polyolefins, effectively reducing the friction between the first resin layer and the oil film, and allows the oil film to slide easily off the first resin layer.

[0017] In the packaging film, it is preferable that a mass ratio of the compatibilizer to the silylated polyolefin is 0.05-20.

[0018] In this case, compared to when the above mass ratio is less than 0.05, aggregation of the silylated polyolefin in the first resin layer is more suppressed, the friction between the first resin layer and the oil film can be effectively reduced, and the oil film can be easily slid off the first resin layer. In addition, compared to when the above mass ratio exceeds 20, coating of the silylated polyolefin with the compatibilizer is suppressed, and aggregation of the silylated polyolefin in the first resin layer is further suppressed, effectively reducing friction between the first resin layer and the oil film, allowing the oil film to slide easily off the first resin layer.

[0019] The present disclosure also relates to a packaging material including the above-mentioned packaging film.

[0020] Since this packaging material contains the above-mentioned packaging film, by heat-treating the packaging material while the oil-in-water dispersion-type contents are in contact with the surface of the first resin layer, it is possible to impart excellent sliding properties to the oil-in-water dispersion-type contents.

[0021] The present disclosure is a packaging bag made using the above-mentioned packaging material, with the first resin layer being disposed on the inside.

[0022] According to this packaging bag, the film for packaging material contained in the packaging material can be heat-treated to give excellent sliding properties to the oil-in-water dispersion-type contents that come into contact with the first resin layer. Therefore, when the oil-in-water dispersion-type contents are sealed in the packaging bag to obtain a package, and then the package is subjected to a heat treatment such as a retort treatment or boiling treatment, the oil-in-water dispersion-type contents can be easily slid down when the oil-in-water dispersion-type contents are discharged from the package after opening the package. Therefore, the amount of residual liquid of the oil-in-water dispersion-type contents can be reduced, waste of the contents can be prevented, stains due to adhesion of the contents can be prevented, and the contents can be efficiently discharged.

[0023] The packaging bag is advantageously used to contain oil-in-water dispersion type contents.

[0024] The present disclosure is a package comprising the above-mentioned packaging bag and an oil-in-water dispersion type content sealed within the packaging bag.

[0025] According to this package, the film for packaging material contained in the package can be heat-treated to impart excellent sliding properties to the oil-in-water dispersion-type contents that come into contact with the first resin layer. Therefore, when the package is subjected to a heat treatment such as a retort treatment or a boiling treatment, the oil-in-water dispersion-type contents can be easily slid down when the oil-in-water dispersion-type contents are discharged from the package after opening the package. Therefore, the amount of residual oil-in-water dispersion-type contents can be reduced, waste of the contents can be prevented, stains due to adhesion of the contents can be prevented, and the contents can be efficiently discharged. Effect of the Invention

[0026] According to the present disclosure, there are provided a film for packaging that can impart excellent sliding properties to oil-in-water dispersions by heat treatment, and a packaging material and package including the same. [Brief description of the drawings]

[0027] [Figure 1] FIG. 1 is a cross-sectional view that illustrates a schematic diagram of one embodiment of a packaging material according to the present disclosure. [Diagram 2] 2(a) to 2(c) are a series of schematic diagrams illustrating the mechanism by which the packaging material according to the present disclosure can impart excellent sliding properties to oil-in-water dispersion-type contents. [Diagram 3] FIG. 3 is a cross-sectional view showing one embodiment of a package according to the present disclosure. [Figure 4] FIG. 4(a) to FIG. 4(e) are a series of schematic diagrams illustrating a method for evaluating the sliding properties of contents in a packaging material. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or equivalent components are denoted by the same reference numerals, and duplicated explanations are omitted. In addition, the dimensional ratios of the drawings are not limited to the illustrated ratios.

[0029] <Packaging material> First, one embodiment of the packaging material of the present disclosure will be described with reference to Figures 1 and 2. Figure 1 is a cross-sectional view that shows a schematic diagram of one embodiment of the packaging material according to the present disclosure, and Figures 2(a) to 2(c) are a series of schematic diagrams that explain the mechanism by which the packaging material according to the present disclosure can impart excellent sliding properties to oil-in-water dispersion-type contents.

[0030] The packaging material 100 shown in FIG. 1 is used to form a packaging bag for containing oil-in-water dispersion type contents. The oil-in-water dispersion type contents are contents that contain water and oil, and the water content is greater than the oil content. The amount of oil contained in the oil-in-water dispersion type contents is, for example, 0.1% by mass or more and less than 50% by mass, and may be 0.5 to 40% by mass or 1 to 20% by mass. Specific examples of the oil-in-water dispersion type contents include curry, hayashi, pasta sauce (for example, meat sauce), and pet food. The amount of oil contained in curry is, for example, about 0.2 to 15% by mass, and the amount of water contained in curry is, for example, about 70 to 90% by mass.

[0031] The packaging material 100 includes a substrate 10, a film for packaging material 20 provided on the substrate 10, and an adhesive layer 30 that bonds the substrate 10 and the film for packaging material 20 together.

[0032] The packaging film 20 includes a first resin layer 21 and a second resin layer 22, and the second resin layer 22 is disposed between the first resin layer 21 and the substrate 1. That is, a surface S of the first resin layer 21 opposite the substrate 10 is exposed. When a packaging bag (e.g., a retort pouch) is formed using the packaging material 100, the surface S of the first resin layer 21 becomes the inner surface of the packaging bag.

[0033] The first resin layer 21 contains a resin composition 21a and a porous filler 21b dispersed in the resin composition 21a. The resin composition 21a contains a resin, and the resin contains a polyolefin and a silylated polyolefin. The oil absorption of the porous filler 21b is 100 to 380 mL / 100 g.

[0034] According to the packaging material 100, the polyolefin contained in the first resin layer 21 of the film 20 for packaging is capable of absorbing oil under the temperature conditions of retort treatment or boiling treatment (80° C. or higher). Therefore, when the packaging material 100 is used for a package containing oil-in-water dispersion type contents C, and the oil-in-water dispersion type contents C are brought into contact with the surface S of the first resin layer 21 of the film 20 for packaging (see FIG. 2(a)), and a heat treatment (heat treatment at 80° C. or higher) such as retort treatment or boiling treatment is performed in this state, the oil C contained in the contents C is absorbed by the packaging material 100. O A part of the oleophilicity of the first resin layer 21 is absorbed into the first resin layer 21 (see FIG. 2(b)), and the lipophilicity of the first resin layer 21 is improved.

[0035] On the other hand, since the first resin layer 21 contains the porous filler 21b, unevenness is formed on the surface S of the first resin layer 21, and it is possible to increase the contact area between the first resin layer 21 and the oil-in-water dispersion type content C, that is, the area through which the oil passes. In addition, since the porous filler 21b has an oil absorption of 100 to 380 mL / 100 g, the oil C O It is possible to effectively adsorb oil C O The oil C contained in the oil-in-water dispersion type content C is adsorbed by O The absorption of the oil into the first resin layer 21 is promoted, and an oil film F is formed on the surface S of the first resin layer 21 by moderate oil absorption. O can be easily formed.

[0036] As a result, an oil film F is formed between the surface S of the first resin layer 21 and the contents C. O Therefore, the contents C, whose surface layer is made of water, are stably formed with the oil film F, which has water repellency. OAs shown in FIG. 2(c), the oil-in-water dispersion type content C becomes slippery against the oil film F simply by tilting the surface S of the packaging material 100. O However, the contents C and the oil film F O Since friction occurs between the first resin layer 21 and the oil film F O The friction between the first resin layer 21 and the oil film F O In this regard, when the first resin layer 21 contains a silylated polyolefin in the resin, the first resin layer 21 and the oil film F are unlikely to slide off. O The friction between the first resin layer 21 and the oil film F O The oil-in-water dispersion type content C becomes oily film F O As a result, the heat treatment of the packaging material 100 can impart excellent sliding properties to the oil-in-water dispersion type content C.

[0037] In addition, since polyolefin has heat-sealing properties, the first resin layer 21 can also function as a sealant film. Therefore, when forming a package, the packaging material 100 can easily form a package by turning the first resin layers 21 inward and heat-sealing the first resin layers 21 together.

[0038] The first resin layer 21, the second resin layer 22, the substrate 10 and the adhesive layer 30 which constitute the packaging material 100 will be described below.

[0039] (First Resin Layer) The first resin layer 21 is a layer that imparts excellent sliding properties to the oil-in-water dispersion type contents C by being subjected to a heat treatment (e.g., retort treatment and boiling treatment) while in contact with the oil-in-water dispersion type contents C.

[0040] (A) Polyolefin The polyolefin may be any polyolefin that is not silylated, and examples of such polyolefins include polypropylene, polyethylene, and polybutylene. Among them, polypropylene is preferred because of its excellent heat resistance. Examples of polyethylene include low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, and ethylene-α-olefin copolymers. Examples of polypropylene include homopolypropylene, block polypropylene, random polypropylene, propylene-α-olefin copolymers, and modified polypropylene. When a combination of block polypropylene and random polypropylene is used as the polypropylene, the mass ratio of the block polypropylene to the random polypropylene (block polypropylene / random polypropylene) is preferably 20 / 80 to 80 / 20, and more preferably 40 / 60 to 60 / 40. In addition to the above, the polyolefin may be a cyclic polyolefin such as polynorbornene. In addition, the polyolefin is preferably a linear polyolefin from the viewpoint of sealability and strength properties (tensile strength, impact strength, etc.), and the linear polyolefin may be linear or branched.

[0041] Examples of the α-olefin component in the ethylene-α-olefin copolymer and the propylene-α-olefin copolymer include ethylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 4-methyl-1-pentene, etc. The copolymer may be a random copolymer or a block copolymer.

[0042] The modified polypropylene is obtained by graft-modifying polypropylene with an unsaturated carboxylic acid derivative component derived from, for example, an unsaturated carboxylic acid, an acid anhydride of an unsaturated carboxylic acid, an ester of an unsaturated carboxylic acid, or the like. In addition, modified polypropylenes such as hydroxyl-modified polypropylene and acrylic-modified polypropylene can also be used as the polypropylene. Examples of the α-olefin component used to obtain the propylene-based copolymer include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, and 4-methyl-1-pentene.

[0043] (C) Silylated polyolefin The silylated polyolefin is a polyolefin that has been silylated, and contains a polyolefin moiety and a silicone moiety.

[0044] Examples of silylated polyolefins include a PE-Si graft copolymer manufactured by Dow Corning Toray Co., Ltd., a PE-Si-PE triblock copolymer manufactured by Exfora manufactured by Mitsui Fine Chemicals Co., Ltd., and a PP-Si graft copolymer manufactured by Dow Corning Toray Co., Ltd. Here, the polyolefin portion of the PE-Si-PE triblock copolymer is polyethylene (PE), and the silicone portion is Si.

[0045] As the silylated polyolefin, a block copolymer is more preferable than a graft copolymer, because the block copolymer is less likely to bleed out from the first resin layer 21.

[0046] The above-mentioned silylated polyolefins can be used alone or in combination of two or more.

[0047] In the first resin layer 21, the amount of silylated polyolefin added is not particularly limited as long as it is greater than 0 mass% based on 100 mass% polyolefin, but is preferably 0.1 to 20 mass%, more preferably 1 to 10 mass%, and particularly preferably 3 to 7 mass%.

[0048] In this case, the first resin layer 21 and the oil film F are more uniform than when the amount of silylated polyolefin added is less than 0.1% by mass based on 100% by mass of polyolefin in the first resin layer 21. O The friction between the first resin layer 21 and the oil film F can be effectively reduced. O In addition, in the first resin layer 21, the oil film F can be easily slid off by the heat treatment, compared with the case where the amount of silylated polyolefin added exceeds 20 mass % based on 100 mass % of polyolefin. O can be more easily formed.

[0049] (D) Compatibilizer The resin composition 21a contained in the first resin layer 21 may or may not contain a compatibilizer that makes the polyolefin and the silylated polyolefin compatible, but when the polyolefin and the polyolefin portion of the silylated polyolefin are incompatible, it is preferable that the resin composition 21a further contains a compatibilizer that makes the polyolefin and the silylated polyolefin compatible.

[0050] In the case where the polyolefin and the polyolefin portion of the silylated polyolefin are incompatible, the first resin layer 21 contains a compatibilizer, which makes it possible to make the polyolefin and the silylated polyolefin compatible with each other. Therefore, the aggregation of the silylated polyolefin is further suppressed, and the first resin layer 21 and the oil film F O The friction between the first resin layer 21 and the oil film F can be effectively reduced. O can be easily slid down.

[0051] More preferably, the compatibilizer comprises a compatibilizer having a first compatible portion that is compatible with the polyolefin and a second compatible portion that is compatible with at least a portion of the silylated polyolefin.

[0052] In this case, the first compatible portion of the compatibilizer becomes compatible with the polyolefin, and the second compatible portion of the compatibilizer becomes compatible with at least a part of the silylated polyolefin. Therefore, the aggregation of the silylated polyolefin is further suppressed, and the first resin layer 21 and the oil film F O The friction between the first resin layer 21 and the oil film F can be effectively reduced. O can be easily slid down.

[0053] The first compatible portion compatible with polyolefin includes a polyolefin portion compatible with polyolefin. The first compatible portion is preferably a polyolefin portion of the same type as polyolefin, since it is easy to obtain better compatibility with polyolefin. That is, when the polyolefin is polyethylene, the first compatible portion is preferably a polyethylene portion, and when the polyolefin is polypropylene, the first compatible portion is preferably a polypropylene portion. In addition, when the polyolefin is a copolymer of two or more olefins such as an ethylene-α-olefin copolymer or a propylene-α-olefin copolymer, the first compatible portion is preferably a portion having at least a structure in which an olefin of the same type as the olefin that is the main component among the olefins constituting the copolymer is polymerized or copolymerized.

[0054] The second compatible portion compatible with at least a part of the silylated polyolefin may be a polyolefin portion compatible with the polyolefin portion of the silylated polyolefin. The second compatible portion is preferably a polyolefin portion of the same type as the polyolefin portion of the silylated polyolefin, since it is easy to obtain better compatibility with the polyolefin portion of the silylated polyolefin. That is, when the polyolefin portion of the silylated polyolefin is a polyethylene portion, the second compatible portion is preferably a polyethylene portion, and when the polyolefin portion of the silylated polyolefin is a polypropylene portion, the second compatible portion is preferably a polypropylene portion. In addition, when the polyolefin portion of the silylated polyolefin is a copolymer portion consisting of two or more kinds of olefins such as an ethylene-α-olefin copolymer portion or a propylene-α-olefin copolymer portion, the second compatible portion is preferably a portion having at least a structure obtained by polymerizing or copolymerizing an olefin of the same type as the olefin that is the main component among the olefins constituting the copolymer portion.

[0055] For example, when polypropylene is used as the polyolefin and a PE-Si-PE triblock copolymer is used as the silylated polyolefin, a PP-PE block copolymer can be used as the compatibilizer. In this case, in the compatibilizer, the first compatible portion is the PP (polypropylene) portion and the second compatible portion is the PE (polyethylene) portion.

[0056] The mass ratio of the compatibilizer to the silylated polyolefin is not particularly limited, but is preferably 0.05-20, more preferably 0.1-10, and particularly preferably 0.5-5.

[0057] In this case, the aggregation of the silylated polyolefin in the first resin layer 21 is more suppressed than when the mass ratio is less than 0.05, and the first resin layer 21 and the oil film F O The friction between the first resin layer 21 and the oil film F can be effectively reduced. OIn addition, compared to the case where the mass ratio exceeds 20, the coating of the silylated polyolefin with the compatibilizer is suppressed, and the aggregation of the silylated polyolefin in the first resin layer 21 is further suppressed, and the first resin layer 21 and the oil film F can be easily slid off. O The friction between the first resin layer 21 and the oil film F can be effectively reduced. O can be easily slid down.

[0058] (B) Porous filler The porous filler 21b is formed by absorbing the oil C absorbed from the oil-in-water dispersion type content C into the first resin layer 21 during the heat treatment. O The porous filler 21b includes a main body portion that adsorbs the above-mentioned substances. The main body portion included in the porous filler 21b may be an inorganic or organic substance. Examples of the organic substance include polyolefin and acrylic resin. Examples of the acrylic resin include cross-linked poly(meth)acrylic ester such as cross-linked polymethyl methacrylate. These may be used alone or in combination of two or more. Examples of the inorganic substance include silica, talc, ceramic, glass beads, mineral fillers such as calcium carbonate, carbon black, glass fiber, ceramic fiber, and carbon fiber. These may also be used alone or in combination of two or more. Examples of the porous filler 21b made of an organic substance include the Techpolymer MBP series manufactured by Sekisui Chemical Co., Ltd. and the Techpolymer ACP series manufactured by Sekisui Chemical Co., Ltd. Examples of the porous filler 21b made of an inorganic substance include the Silo Hobic series manufactured by Fuji Silysia Chemical Co., Ltd. and the Sunsphere series manufactured by AGC Si-Tech Co., Ltd.

[0059] The porous filler 21b may further include a coating portion that coats at least a part of the main body portion. The coating portion may be made of either a hydrophilic or hydrophobic material, but is preferably made of a hydrophobic material. Here, the hydrophobic material refers to a material having a DBA (di-n-butylamine) value of 200 mEq / kg or less, and the DBA value refers to the amount of DBA adsorbed on the surface of the main body portion. The DBA value corresponds to the amount of DBA adsorbed to the hydroxyl groups on the surface of the main body portion, and the smaller the DBA value, the fewer the hydroxyl groups (the higher the hydrophobicity).

[0060] The porous filler 21b composed of the main body and the coating can be obtained, for example, by chemically reacting the main body with a hydrophobic material, that is, by subjecting the main body to a hydrophobic treatment. Examples of the hydrophobic material include organosilicon compounds. Among them, organosilicon compounds are preferred as the hydrophobic material.

[0061] The oil absorption of the porous filler 21b is 100 to 380 mL / 100 g. Here, the "oil absorption" refers to the oil absorption measured in accordance with JIS K5101-13 (Pigment testing method-Part 13: oil absorption).

[0062] When the oil absorption of the porous filler 21b is within the above range, the oil content C is reduced during the heat treatment of the packaging material 100 compared to when the oil absorption is less than 100 mL / 100 g. O It is possible to effectively adsorb the oil C contained in the oil-in-water dispersion type content C. O Since the film for packaging 20 can promote the absorption of the oil into the first resin layer 21, the film for packaging 20 can effectively impart excellent sliding properties to the oil-in-water dispersion type contents C enclosed in the package. In addition, compared to the case where the oil absorption amount exceeds 380 mL / 100 g, the porous filler 21b appropriately adsorbs the oil, and an oil film F is formed on the surface S of the first resin layer 21. O Since the film for packaging 20 is easily formed, it is possible to impart better sliding properties to the oil-in-water dispersion type contents C enclosed in the package.

[0063] The oil absorption of the porous filler 21b is more preferably 110 mL / 100 g or more, and particularly preferably 120 mL / 100 g or more.

[0064] However, the oil absorption of the porous filler 21b is preferably 300 mL / 100 g or less. In this case, the porous filler 21b more appropriately adsorbs oil, so that an oil film F O Since this makes it easier to form the above-mentioned, the film for packaging material 20 can impart better sliding properties to the oil-in-water dispersion type content C enclosed in the package.

[0065] The average particle size (Y μm) of the porous filler 21b is determined by the following method depending on the type of filler. (Calculation method using laser diffraction particle size distribution measurement) (1) The porous filler 21b is dispersed in a dispersion medium. The dispersion medium is, for example, water or an organic solvent, and an appropriate one is selected depending on the type of filler. (2) Using a laser diffraction particle size distribution measuring device (product name: "MT3300EX II", manufactured by Microtrackbell), the average particle size of the porous filler 21b is calculated by a laser diffraction / scattering method. (Calculation method based on microscopic observation) When the above-mentioned laser diffraction type particle size distribution measurement is not suitable or is difficult, the average particle size of the porous filler 21b may be obtained using an optical microscope such as a scanning electron microscope (SEM) or a laser microscope. The particle diameter is determined by measuring the longest and shortest diameters of any particle in the field of view observed by a microscope, and dividing the sum by 2. The particle diameters of multiple particles are measured and calculated, and the average value is regarded as the average particle diameter. The number of any particles is preferably 10 or more.

[0066] The average particle size (Y μm) of the porous filler 21b is not particularly limited, but is preferably 5 μm or more. In this case, an appropriate amount of the porous filler 21b can provide appropriate unevenness to the surface S of the first resin layer 21, so that the sliding property of the contents C can be effectively improved while reducing the influence on the physical properties of the packaging film 20, such as a decrease in seal strength.

[0067] The average particle size (Y μm) of the porous filler 21b is more preferably 3 μm or more, and particularly preferably 7 μm or more.

[0068] However, the average particle diameter (Y μm) of the porous filler 21b is preferably 30 μm or less. In this case, the oil film F on the surface S of the first resin layer 21 is smaller than when the average particle diameter (Y μm) of the porous filler 21b exceeds 30 μm. O This makes it easier to form the film for packaging material 20, and allows the film for packaging material 20 to impart better sliding properties to the oil-in-water dispersion type content C enclosed in the package.

[0069] The average particle size (Y μm) of the porous filler 21b is more preferably 20 μm or less, and further preferably 15 μm or less.

[0070] In the first resin layer 21, the amount of the porous filler 21b added is, for example, 0.5 to 10 mass %, preferably 1 to 8 mass %, and more preferably 2 to 8 mass %, relative to 100 mass % of the polyolefin. When the amount of the porous filler 21b added is within the above range, it is possible to impart appropriate unevenness to the surface S of the first resin layer 21.

[0071] The thickness (X μm) of the first resin layer 21 is a value determined as follows. (1) First, a packaging film 20 is fixed with an embedding resin (acrylic resin) to prepare a structure. (2) A sample for cross-sectional observation is cut out from the structure using a microtome. (3) Observe the cross section of the cut sample for cross-sectional observation using a microscope (product name: VHX-1000, manufactured by Keyence Corporation). (4) The thickness is measured at three points along the thickness direction of the first resin layer 21 where no porous filler 21b is present, and the average value of the thicknesses at these three points is calculated as the thickness (X μm) of the first resin layer 21.

[0072] The thickness (X μm) of the first resin layer 21 is, for example, 2 to 100 μm, preferably 4 to 70 μm, more preferably 6 to 50 μm, and even more preferably 8 to 30 μm. When the thickness of the first resin layer 21 is within the above range, both the sliding property of the contents C and the heat sealability can be achieved at a high level. Here, the heat sealability means, for example, a property that allows heat sealing under conditions of 100 to 200° C., 0.1 to 0.3 MPa, and 1 to 3 seconds.

[0073] (Second Resin Layer) The second resin layer 22 is a layer provided between the first resin layer 21 and the substrate 10. By further providing the packaging material 100 with the second resin layer 22, the packaging material 100 can be provided with a function corresponding to the function of the second resin layer 22 (heat sealability, heat resistance and impact resistance, oxygen and water vapor barrier property, etc.). For example, from the viewpoint of improving the heat sealability, it is preferable that the second resin layer 22 contains a thermoplastic resin. Specific examples of the thermoplastic resin include polyolefin, ethylene-α,β-unsaturated carboxylic acid copolymer or its ester or ion crosslinked product, ethylene-vinyl acetate copolymer or its saponification product, polyvinyl acetate or its saponification product, polycarbonate resin, thermoplastic polyester resin, ABS resin, polyacetal resin, polyamide resin, polyphenylene oxide resin, polyimide resin, polyurethane resin, polylactic acid resin, furan resin, and silicone resin. These thermoplastic resins can be used alone or in combination of two or more.

[0074] The thickness of the second resin layer 22 can be appropriately set depending on the application of the packaging material 100. The thickness of the second resin layer 22 is, for example, 1 to 300 μm, preferably 2 to 200 μm, more preferably 5 to 150 μm, and even more preferably 10 to 100 μm.

[0075] (base material) The substrate 10 is not particularly limited as long as it serves as a support and has durability against heat treatment such as retort treatment or boiling treatment, and examples thereof include resin films and metal foils. Examples of resin films include films containing at least one of polyolefins (e.g., polyethylene (PE), polypropylene (PP), etc.), acid-modified polyolefins, polyesters (e.g., polyethylene terephthalate (PET), etc.), polyamide (PA), polyvinyl chloride (PVC), cellulose acetate, and cellophane resins. This film may be a stretched film or a non-stretched film. Examples of metal foils include aluminum foil and nickel foil. The substrate 10 may be a laminate of a plurality of substrates made of different materials, and may include a coating layer or a metal deposition layer.

[0076] The thickness of the substrate 10 can be appropriately set depending on the application of the packaging material 100. The thickness of the substrate 10 is, for example, 1 to 500 μm, and may be 10 to 100 μm.

[0077] (adhesive layer) The adhesive layer 30 bonds the film for packaging material 20 (a laminate of the first resin layer 21 and the second resin layer 22) to the substrate 10. The adhesive constituting the adhesive layer 30 is not particularly limited as long as it can bond the film for packaging material 20 to the substrate 10, and examples of such adhesives include polyurethane resins in which a bifunctional or higher isocyanate compound is allowed to react with a base material such as polyester polyol, polyether polyol, acrylic polyol, or carbonate polyol. The various polyols may be used alone or in combination of two or more.

[0078] For the purpose of promoting adhesion, the adhesive layer 30 may contain a carbodiimide compound, an oxazoline compound, an epoxy compound, a phosphorus compound, a silane coupling agent, or the like, in the above-mentioned polyurethane resin. Depending on the performance required for the adhesive layer 30, the above-mentioned polyurethane resin may contain various other additives and stabilizers.

[0079] The thickness of the adhesive layer 30 is, for example, 1 to 10 μm, and may be 3 to 7 μm, from the viewpoint of obtaining desired adhesive strength, conformability, processability, and the like.

[0080] An adhesive primer (anchor coat) can be applied to the substrate 10, and examples of the material that can be used include polyester resins, polyurethane resins, polyallylamine resins, polyethyleneimine resins, polybutadiene resins, ethylene-vinyl acetate copolymers, and chlorine-vinyl acetate resins. The adhesive primer may contain various curing agents and additives that can be used as adhesives, as necessary.

[0081] <Manufacturing method of packaging materials> Next, a method for producing the above-mentioned packaging material 100 will be described.

[0082] The packaging material 100 can be obtained by laminating the packaging film 20 and the substrate 10 with an adhesive. Examples of a method for bonding the substrate 10 and the packaging film 20 include a lamination method using an adhesive and a lamination method using heat treatment.

[0083] As a lamination method using an adhesive, various known lamination methods such as a dry lamination method, a wet lamination method, a non-solvent lamination method, etc. can be used.

[0084] Lamination methods using heat treatment can be roughly classified into the following methods (1) to (4). (1) A method of extruding an adhesive resin between a packaging film 20 and a substrate 10 that have been previously prepared, and laminating them. (2) A method in which the packaging film 20 and an adhesive resin are co-extruded and laminated to the substrate 10 with the adhesive resin facing the substrate 10 side. (3) A method in which the laminate obtained by the above method (1) or (2) is further heated and pressed with a heat roll to bond the laminate. (4) The laminate obtained by the above method (1) or (2) is further stored in a high-temperature atmosphere or passed through a drying / baking furnace in a high-temperature atmosphere.

[0085] <Packaging bags and packaging> Next, one embodiment of the package of the present disclosure will be described with reference to Fig. 3. Fig. 3 is a cross-sectional view showing one embodiment of the package of the present disclosure.

[0086] 3, the packaging body 300 includes a packaging bag 200 and an oil-in-water dispersion type content C sealed in the packaging bag 200. In the packaging body 300, the first resin layer 21 of the packaging film 20 of the packaging bag 200 is disposed on the inner side and is in contact with the oil-in-water dispersion type content C.

[0087] According to the above-mentioned package 300, the film 20 for packaging material included in the packaging material 100 forming the packaging bag 200 can provide excellent sliding properties to the oil-in-water dispersion type contents C that come into contact with the first resin layer 21 by heat treatment. Therefore, when the package 300 is subjected to a heat treatment such as a retort treatment or a boiling treatment, the oil-in-water dispersion type contents C can be easily slid down when the oil-in-water dispersion type contents C are discharged from the package 300 after the package 300 is opened. Therefore, the amount of residual liquid of the oil-in-water dispersion type contents C can be reduced, waste of the contents C can be prevented, stains due to adhesion of the contents C can be prevented, and the discharge operation of the contents C can be efficiently performed.

[0088] The above-mentioned package 300 can be obtained by forming a packaging bag 200 using the packaging material 100 and enclosing an oil-in-water dispersion type content C in the packaging bag 200.

[0089] Although the embodiment of the present disclosure has been described in detail above, the present disclosure is not limited to the above embodiment. For example, in the above embodiment, the film for packaging material 20 is composed of the first resin layer 21 and the second resin layer 22, but the film for packaging material 20 may be composed of only the first resin layer 21, or may further include one or more resin layers.

[0090] In addition, the packaging material 100 has an adhesive layer 30 that bonds the packaging film 20 and the substrate 10, but if the packaging film 20 and the substrate 10 can be directly fused together, the adhesive layer 30 can be omitted.

[0091] Furthermore, the packaging material 100 does not necessarily have to have the substrate 10 . EXAMPLES

[0092] The present disclosure will be described more specifically below with reference to examples and comparative examples, but the present disclosure is not limited to the following examples.

[0093] The materials used in the examples and comparative examples are as follows. (A) Polyolefin (A1)PP1 A mixture of a propylene-ethylene random copolymer (product name "F744NP", manufactured by Prime Polymer Co., Ltd.) and a propylene-ethylene block copolymer (product name "Novatec BC5FA", manufactured by Japan Polypropylene Corporation) in a 1:1 (mass ratio) mixture. (A2)PP2 Block polypropylene (propylene-ethylene block copolymer, product name "Novatec BC3HF", manufactured by Japan Polypropylene Corporation) (A3)PE Linear low-density polyethylene (LLDPE, product name "Novatec LL UF442", manufactured by Japan Polypropylene Corporation)

[0094] (B) Porous filler (B1) Porous silica filler Average particle size: 20 μm, oil absorption: 150 mL / 100 g, hydrophobic treatment: none, product name "Sunsphere H-201", manufactured by AGC Si-Tech Co., Ltd. (B2) Porous silica filler Average particle size: 12 μm, oil absorption: 300 mL / 100 g, hydrophobic treatment: none, product name "Sunsphere H-122", manufactured by AGC Si-Tech Co., Ltd. (B3) Porous silica filler Average particle size: 7 μm, oil absorption: 120 mL / 100 g, hydrophobic treatment: none, product name "Sunsphere L-71-N", manufactured by AGC Si-Tech Co., Ltd. (B4) Porous silica filler Average particle size: 4.1 μm, oil absorption: 170 mL / 100 g, DBA value: 65 mEq / kg, product name "Silohobic 702", manufactured by Fuji Silysia Chemical Ltd. (B5) Porous silica filler Average particle size: 6.7μm, oil absorption: 50mL / 100g, DBA value: 200mEq / kg, product name "Silohobic 603", manufactured by Fuji Silysia Chemical Ltd. (B6) Porous silica filler Average particle size: 5 μm, oil absorption: 400 mL / 100 g, hydrophobic treatment: none, product name "Sunsphere H-53", manufactured by AGC Si-Tech Co., Ltd.

[0095] (C) Silylated polyolefin PE-Si-PE triblock copolymer: Trade name "EXFOLA", manufactured by Mitsui Fine Chemicals, Inc.

[0096] (D) Compatibilizer Polypropylene-Polyethylene Block Copolymer

[0097] <Production of packaging materials> (Examples 1 to 19 and Comparative Examples 1 to 5) Using a co-extruder, a two-layered packaging film (sealant film) was produced, which had a first resin layer having the composition shown in Tables 1 and 2 and a second resin layer having the composition shown in Tables 1 and 2. In Tables 1 and 2, the "addition amount (mass %)" is the amount added relative to 100 mass % of polyolefin.

[0098] Next, the obtained packaging film and a 38 μm-thick PET film (product name "Emblett", manufactured by Unitika Ltd.) as a base material were dry laminated using a polyurethane adhesive (manufactured by Mitsui Chemicals Inc.) and aged at 50° C. for 5 days to obtain a packaging material. In the examples and comparative examples, the first resin layer and the second resin layer were formed so that the total thickness of the first resin layer and the second resin layer was 60 μm.

[0099] <Evaluation of contents slipping off> (Evaluation of residual liquid after retort processing) The packaging materials obtained in the Examples and Comparative Examples were evaluated for the slippage of the contents after retort treatment by the methods shown in Figs. 4(a) to 4(e).

[0100] First, two sheets of packaging material cut to 150 mm long x 138 mm wide were prepared. The two sheets of packaging material were then stacked with the first resin layer facing inward, and the three sides were sealed using a heat sealer. In this way, as shown in FIG. 4(a), a packaging bag 200 was produced that had a sealed portion 200a formed on three sides and was composed of a pouch with one side open. At this time, the heat sealing of the three sides was performed under conditions of 190°C, 0.03 MPa, and 2 seconds, and the width of the sealed portion 200a was 10 mm.

[0101] Next, as shown in FIG. 4(b), 180 g of curry (product name "Bon Curry Gold Medium Spicy", lipid content 7.0 g / 180 g, manufactured by Otsuka Foods Co., Ltd.) was poured as content C from the opening of packaging bag 200.

[0102] Thereafter, the opening (the remaining side) was sealed using a heat sealer to form a sealed portion 200b on the remaining side as shown in Fig. 4(c). In this way, a package 300 was produced in which the four sides were sealed and the content C was enclosed. At this time, the heat sealing of the opening was performed under conditions of 190°C, 0.03 MPa, and 2 seconds, and the width of the sealed portion 200b was 10 mm.

[0103] The package 300 thus produced was placed in a high-temperature, high-pressure cooking and sterilizing device (manufactured by Hitachi Capital Corporation) and subjected to a retort treatment with high-temperature steam. The retort treatment was carried out under the following conditions. Pressure: 0.2MPa ·Temperature 121℃ Processing time: 30 minutes

[0104] After the retort treatment, the package 300 was subjected to a hot water bath treatment at 100°C for 5 minutes. Thereafter, as shown in Fig. 4(d), the upper part of the package 300 was cut to form a spout. Next, as shown in Fig. 4(e), the pouch was turned upside down and the spout was tilted 45° from the horizontal plane and held for 10 seconds, discharging the content C into the container 400, and the amount discharged was weighed using the scale 500. The residual liquid rate (%) was calculated from the weighed amount discharged using the following formula. Residual liquid rate (%)={(180-discharge amount) / 180}×100 The same measurement was carried out three times by changing the package 300, and the average of the three remaining liquid rates was calculated as the average remaining liquid rate. In addition, based on the average remaining liquid rate, the slipping off property of the contents was evaluated according to the following evaluation criteria. The evaluation results of the average remaining liquid rate and the slipping off property of the contents are shown in Tables 1 and 2. A: Average residual liquid rate is less than 6.5% B: Average residual liquid rate is 6.5% or more and less than 8.0% C: Average residual liquid rate is 8.0% or more and less than 10.0% D: Average residual liquid rate is 10.0% or more

[0105] (Appearance evaluation after retort processing) When measuring the residual liquid rate as described above, the discharge behavior of the content C (curry) when it was discharged from the pouch was visually observed, and the appearance was also evaluated according to the following evaluation criteria. The results are shown in Tables 1 and 2. A: The contents appear to slide off cleanly, with almost no adhesion to the packaging film. B: The contents were seen to slide down, and the amount of the contents adhering to the packaging film was small. C: The contents appear to slide down, but a large amount of the contents adheres to the packaging film. D: There is no sign of the contents slipping off.

[0106] [Table 1] [Table 2]

[0107] From the results shown in Tables 1 and 2, the average residual liquid rate was small and the contents were visible on the outside in the packages obtained in Examples 1 to 19. In contrast, the average residual liquid rate was large in the packages obtained in Comparative Examples 1 to 5 and the contents were not visible on the outside in the packages.

[0108] From the above, it was confirmed that the packaging film of the present disclosure can be provided with excellent sliding properties for oil-in-water dispersion-type contents by heat treatment. [Explanation of symbols]

[0109] 10...substrate, 20...film for packaging material, 21...first resin layer, 21a...resin composition, 21b...porous filler, 30...adhesive layer, 100...packaging material, 200...packaging bag, 300...package, C...contents, C O …Oil content, S…Surface of the first resin layer, F O ...Oil slick.

Claims

1. A first resin layer including a resin and a porous filler, the resin comprises a polyolefin and a silylated polyolefin; The average particle size of the porous filler is 12 μm or more, The porous filler has an oil absorption of 100 to 380 mL / 100 g.

2. 2. The packaging film according to claim 1, wherein the amount of the silylated polyolefin added in the first resin layer is 0.1 to 20% by mass based on 100% by mass of the polyolefin.

3. the polyolefin and the polyolefin portion of the silylated polyolefin are incompatible with each other, 3. The packaging film according to claim 1, wherein the first resin layer further comprises a compatibilizer having a first compatible portion compatible with the polyolefin and a second compatible portion compatible with at least a portion of the silylated polyolefin.

4. The packaging film according to claim 3, wherein a mass ratio of the compatibilizer to the silylated polyolefin is 0.05 to 20.

5. A packaging material comprising the film for packaging material according to any one of claims 1 to 4.

6. A packaging bag made using the packaging material according to claim 5, wherein the first resin layer is disposed on the inside.

7. The packaging bag according to claim 6, which is used to contain an oil-in-water dispersion type content.

8. The packaging bag according to claim 7, A package comprising an oil-in-water dispersion type content sealed in the packaging bag.

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