JP2022035757A - Laminate material for lid, and package - Google Patents

Abstract

To provide a laminate material for a lid made of a metal laminate packaging material in which an outermost surface is covered with a protective resin layer and a printed layer is disposed on an inner surface side thereof, and in which fractures, such as peeling off, falling off and dislocation, do not occur in the printed layer even when an external force, such as impact, is exerted on the protective resin layer.SOLUTION: A laminate material for a lid 10 is designed to release an external force along an outermost surface by causing a lubricant S to exist on the outermost surface of a protective resin layer 11.SELECTED DRAWING: Figure 1

Description

The present invention relates to a laminated material for a lid for heat-sealing a container filled with various contents, and a package body heat-sealed with a lid made of the laminated material.

Conventionally, many products such as foods such as lactic acid bacteria beverages, soft drinks and yogurt, pharmaceuticals such as granule preparations and tablets, and sanitary products such as gauze and naphthin (hereinafter, may be simply referred to as contents) have been made of synthetic resin or. After filling in a molded container made of metal, paper, etc., the heat-sealing layer made of heat-sealing resin is heat-sealed with a lid arranged on the lowermost surface to market the market in a sealed package. It is distributed and displayed in stores.

The lid is generally made of various metal laminated packaging materials for the purpose of protecting the contents from light, gas, moisture and the like. This metal laminating packaging material is a laminated material in which a barrier layer made of a metal foil such as an aluminum alloy foil is arranged in the middle of the thickness, and a printing layer is provided on the outer surface side of the barrier layer, and the product name and components of the contents are provided. Information such as, bar code, design, etc. may be displayed. Further, in order to protect the print information, a synthetic resin film such as polyethylene terephthalate is laminated on the print layer as a protective resin layer, or as shown in Patent Documents 1 to 3, an overprint coat layer made of various coating agents is used. May form.

Japanese Unexamined Patent Publication No. 2014-031016 Japanese Unexamined Patent Publication No. 2014-062234 Japanese Unexamined Patent Publication No. 2019-206387

By the way, the package is transported from the factory to the consumer via the warehouse and the store, but the surface of the lid is strongly rubbed or shocked due to vibration during transportation or transportation or improper handling. The printed layer may be peeled off or dropped off together with the protective resin layer, or the printed surface may be misaligned. In particular, when the lid has a cap-like shape having a skirt portion as shown in FIG. 4, for example, such a defect is likely to occur at the edge portion.

As a means for solving the above problem, for example, a method of forming a protective resin layer with a thermosetting overcoating agent having a high crosslinkability, or a method of forming a printing ink layer with, for example, an ultraviolet curable ink can be mentioned. Although all of them have a certain effect, they lack versatility in that the types of coating agents and printing inks can be limited.

The present invention is a laminated material for a lid in which a protective resin layer, a printing layer, a barrier layer made of a metal foil, and a heat seal layer made of a thermoplastic resin are laminated in this order from the outside. The main object of the present invention is to provide a laminated material in which defects such as peeling, falling off, and misalignment of the printed layer do not occur even when an external force is applied or strong friction is generated.

The present inventor has made a material for the protective resin layer as long as the external force can be released along the outermost surface of the lid even if some object comes into contact with the protective resin layer constituting the laminated material for the lid and an external force is applied. The idea was that the defects in the printing layer could be prevented without particularly limiting the types of printing inks. Then, they have found that a lid that can solve the above-mentioned problems can be realized by allowing a lubricant to be present on the outermost surface of the protective resin layer to reduce the frictional force caused by the external force, and have completed the present invention. That is, the present invention relates to a laminated lumber for a lid having the following structure and a package having the laminated lumber for a lid as an element.

1) A laminated material for a lid that is heat-sealed to the peripheral edge of the opening so as to cover the opening of the container filled with the contents. A laminated material for a lid, which has a barrier layer and a heat seal layer made of a thermoplastic resin, and has a lubricant present on the outermost surface of the protective resin layer.

2) The laminated lumber for the lid of 1) in which a lubricant is contained in the thermoplastic resin forming the heat seal layer.

3) The laminated material for a lid according to 1) or 2), wherein the outermost surface of the protective resin layer in which the lubricant is present has a coefficient of dynamic friction of 0.05 to 0.5.

4) The laminate for the lid according to any one of 1) to 3), wherein the amount of the lubricant present on the outermost surface of the protective resin layer is 0.05 to 1.0 μg / cm ² .

5) A package in which a lid made of the laminate for the lid according to any one of 1) to 4) is heat-sealed to the peripheral edge of the opening of the container filled with the contents.

The outermost surface of the laminated material for the lid of 1) is formed of a protective resin layer, and a lubricant is present on the outermost surface of the protective resin layer. Therefore, this protective resin layer exhibits external slipperiness, and even if an external force such as an impact is applied, the frictional force is reduced, so that the external force escapes along the outermost surface of the protective resin layer. Will be. As a result, defects such as dropping and peeling are less likely to occur in the print layer arranged on the lower surface of the protective resin layer. Therefore, a package in which a container containing contents is heat-sealed with a lid made of this laminated material for a lid may collide with each other during transportation, for example, or may collide with the bottom of the upper package in a state where a plurality of packages are packed. Even if some external force is applied to the lid, such as by rubbing against the upper surface of the lid of the lower package, defects are unlikely to occur in the printed layer, and misalignment and blurring of printed product information and designs are avoided. It will be possible. This means, for example, when the packaging bodies are stacked and displayed on the product shelves at the time of sale, the bottom of the upper packaging body and the lid of the lower packaging body rub against each other, or the packaging body falls from the product shelf and the top surface of the lid is displayed. The same applies when an impact is applied to the product.

The laminated material for the lid in 2) contains a lubricant in advance in the heat-sealing resin that forms the heat seal layer on the innermost surface, so that the internal pressure is constant when it is wound into a roll during mass production. When exposed to temperature, the lubricant contained in the heat-sealing resin gradually bleeds out and precipitates on the innermost surface of the heat seal layer, and the precipitated lubricant is brought into contact adjacent to the heat seal layer. It moves to the outermost surface of the protective resin layer. Then, the laminated material for the lid after rewinding exhibits external slipperiness as a result of the presence of the lubricant on the outermost surface of the protective resin layer, and has the same effect as the laminated material for the lid in 1). ..

The lid laminate of 3) has some external force because the dynamic friction coefficient of the protective resin layer in which the lubricant is present on the outermost surface of the lid laminate of 1) or 2) is limited to a predetermined range. Is added, defects in the print layer are less likely to occur. In addition, since the external slipperiness of this laminated material for lids is appropriately adjusted, when opening a heat-sealed package with a lid made of this, slipping of fingers on the lid is less likely to occur, and opening work is easy. Become.

The lid laminate of 4) is printed because the amount of lubricant present on the outermost surface of the protective resin layer is limited to a predetermined range in any of the lid laminates 1) to 3). Layer defects are less likely to occur.

The package of 5) is a sealed body in which a lid made of the laminate for the lid of any of 1) to 4) is heat-sealed at the peripheral edge of the opening of the container filled with the contents. The outermost surface is covered with a predetermined protective resin layer having external slipperiness. Therefore, an external force is applied to the lid, for example, the packages collide with each other during transportation, or the bottom of the upper package and the upper surface of the lid of the lower package rub against each other in a state where a plurality of packages are packed. Even so, defects are less likely to occur in the printed layer, and it is possible to avoid misalignment and blurring of printed product information and designs. This means, for example, when the packaging bodies are stacked and displayed on the product shelves at the time of sale, the bottom of the upper packaging body and the lid of the lower packaging body rub against each other, or the packaging body falls from the product shelf and the top surface of the lid is displayed. The same applies when an impact is applied to the product.

It is a vertical sectional view of the laminated lumber for a lid of this invention. A coil made of the laminated lumber for a lid of the present invention, a vertical cross-sectional view of the laminated lumber for the lid in this coil, and a vertical cross-sectional view of the laminated lumber for the lid in a state where the coil is rewound are shown. It is a vertical sectional view of one Embodiment of the package of this invention. It is a perspective view of the cap-shaped lid which has a skirt part. It is a conceptual diagram of the method of testing the external slipperiness of the protective resin layer of the laminated lumber for a lid of this invention. It is a conceptual diagram of the method of testing the external slipperiness about the protective resin layer of the lid which forms the package of this invention.

Hereinafter, the laminate for the lid and the package of the present invention will be described in detail with reference to FIGS. 1 to 6, but the technical scope of the present invention is not limited by these drawings.

FIG. 1 is a cross-sectional view of the laminated lumber (10) for a lid of the present invention (hereinafter, simply abbreviated as the laminated lumber (10)). The laminated lumber (10) of FIG. 1 (a) has a protective resin layer (11), a printing layer (12), an outer surface side anchor coat layer (13), a barrier layer (14), and an inner surface in this order from the outside. The side anchor coat layer (15), the cushioning material layer (16), and the heat seal layer (17) are laminated in this order. Further, a particulate lubricant (S) is adhered to the outermost surface of the protective resin layer (11), and a lubricant layer (11S) having a predetermined thickness made of the lubricant (S) is conceived. FIG. 1 (b) schematically shows how the form of the lubricant (S) is discarded in the laminated lumber (10) of FIG. 1 (a) to form a single lubricant layer (11S) conceptually. Shown in. FIG. 1 (c) schematically shows how the heat-sealed layer (17) contains the particulate lubricant (S) in the laminated material (10) of FIG. 1 (b). FIG. 1 (d) schematically shows how the lubricant (S) is bleeded out to the innermost surface of the heat seal layer (17) in the laminated lumber (10) of FIG. 1 (c). The morphology of the lubricant (S) and the lubricant layer (11S) in each figure and the distribution state of the lubricant (S) in the heat seal layer (17) all describe the embodiment of the present invention conveniently and conceptually. It is a thing. Further, in each figure, the outer surface side anchor coat layer (13), the inner surface side anchor coat layer (15), and the cushioning material layer (16) can all be omitted.

FIG. 2 shows the layer structure when the laminated material (10) of FIG. 1 (c) is wound around a core material so that the heat seal layer (17) is on the inner surface to form a roll-shaped coil. It is a conceptual diagram. In FIG. 2 (a), the lubricant (S) bleeded out to the innermost surface of the heat seal layer (17) by aging the coiled laminate (10) in FIG. 2 (b) is the same. A lubricant having a predetermined thickness is brought into contact with the outermost surface of the protective resin layer (11), which is in close contact with the lower surface of the heat seal layer (17), and at the interface between the heat seal layer (17) and the protective resin layer (11). The state in which the layer (11S) is formed is schematically shown. FIG. 2B is a schematic diagram of a coil formed by winding a laminated material (10). In FIG. 2 (c), in the rewound laminated lumber (10), a lubricant layer (11S) having a predetermined thickness made of a lubricant (S) is formed on the outermost surface of the protective resin layer (11). , A state in which a part of the precipitation phase due to the bleed-out remains on the innermost surface of the heat seal layer (17) is schematically shown. In addition, in FIGS. 2 (a) and 2 (c), the outer surface side anchor coat layer (13), the inner surface side anchor coat layer (15) and the cushioning material layer (16) are all omitted.

FIG. 3 is a cross-sectional view of a package (3) formed by heat-sealing a container (2) with a lid (1) made of a laminated material (10). The package (3) of FIG. 3 (a) is a flange in which the lid (1) is single-wafered and the opening peripheral edge (21) of the container (2) is substantially horizontal and has a significant width. In the package (3) of FIG. 3 (b), the lid (1) is in the shape of a cap and the opening peripheral portion (21) is in the form of a substantially upright rim. Each package (3) is filled with the content (C).

The protective resin layer (11) constitutes each outermost surface of the laminated lumber (10) and the lid (1), and enhances their strength, durability, weather resistance, chemical resistance, and the like. Since the lubricant (S) is present on the outermost surface of the protective resin layer (11), the lid (1) and other objects may rub against each other, or an impact may be applied to the lid (1). Even so, these external forces are released along the outermost surface of the protective resin layer (11), resulting in defects in the printed layer (12) that may occur unexpectedly during transportation or display of the package (3). It is possible to prevent it in advance. In addition, "existing" specifically means that the lubricant (S) is attached to the outermost surface of the protective resin layer (11) by some external means, and is adsorbed, bound, and bonded. Includes aspects such as vapor deposition and welding. However, the embodiment in which the lubricant (S) is previously contained in the protective resin layer (11) and is precipitated by bleed-out to be fixed on the outermost surface of the protective resin layer (11) is excluded.
As the lubricant (S), various known waxes and / or surfactants can be used without particular limitation.
As the wax, natural wax and / or synthetic wax can be used. Natural waxes include animal and vegetable waxes such as candelilla wax, carnauba wax, rice wax, wood wax, beeswax, whale wax, shelac wax and lanolin wax; mineral waxes such as montan wax, ozokelite and selecin; paraffin wax and microcrystallin. Examples include waxes and petroleum waxes such as petrolatum, which can be used alone or in combination of two or more. On the other hand, as synthetic waxes, for example, hydrocarbon-based synthetic waxes such as polyethylene wax, polypropylene wax and Fishertropush wax; hydride waxes such as cured castor oil and cured castor oil derivative; styrene grafted on a polyethylene-polypropylene copolymer. Modified waxes, silicone waxes (silicone waxes), fluorine waxes and amide waxes (oleic acid amides, ricinoleic acid amides, erucic acid amides, N, N'-methylenebistearic acid amides, N, N'- Examples include ethylene bisoleic acid amide, stearic acid monomethylol amide, silinolic acid amide wax, stearic acid ester wax, etc.) and modified waxes such as composites thereof, which may be used alone or in combination of two or more. can. Among the waxes, hydrocarbon-based synthetic waxes and modified waxes (particularly silicon-based waxes and amide-based waxes) are not only stable as materials, but also dispersed when present on the outermost surface of the protective resin layer (11). In addition to being excellent in property (diffusivity), it is preferable in that the external slipperiness of the protective resin layer (11) is further improved. Further, the hydrocarbon-based synthetic wax and the modified wax are also suitable as a means for adjusting the fluidity of the heat-sealing layer (17) melted at the time of heat-sealing when they are contained in the heat-sealing layer (17) described later. Is. The shape of the wax is not particularly limited and may be in the form of a paste, flakes or particles.
Examples of the surfactant include at least one selected from the group consisting of anionic surfactants, cationic surfactants, amphoteric surfactants and nonionic surfactants. Examples of the anionic surfactant include ricinoleic acid sulfate ester soda, ricinoleic acid ester sulfate ester soda, sulfated amide, olefin sulfate ester salt, aliphatic alcohol sulfate ester salt, alkyl sulphonate, and alkyl naphthalen sulphonate. , Alkylbenzene sulphonate, arsenic sulphonate, etc. Examples of the cationic surfactant include a primary amine salt, a tertiary amine salt, a quaternary ammonium compound, a pyridine derivative and the like. Examples of the amphoteric surfactant include a carboxylic acid derivative and an imidazoline derivative. Examples of the nonionic surfactant include a partial fatty acid ester of a polyhydric alcohol, an ethylene oxide adduct of a fatty alcohol, an ethylene oxide adduct of a fatty acid, an ethylene oxide adduct of an aliphatic amino or an aliphatic amide, and an ethylene of an alkylphenol. Examples thereof include an oxide adduct, an ethylene oxide adduct of a partial fatty acid ester of a polyhydric alcohol, and the like.
The wax and the surfactant may be used in combination, and the action of the surfactant improves the dispersibility of the wax in various media, and the outermost surface of the protective resin layer (11) provides a more homogeneous lubricant layer (11S). It may be possible to form.

The protective resin layer (11) can be composed of various known overcoating agents and / or synthetic resin films. The overcoat agent is a composition obtained by dissolving various known binder resins in a solvent. Examples of the binder resin include nitrified cotton (nitrocellulose), shellac resin, epoxy resin, polyurethane resin, chlorinated polyolefin resin, acrylic resin, vinyl chloride-vinyl acetate copolymer and the like, and a combination of two or more thereof may be used. May be good. Examples of the solvent include organic solvents such as toluene, xylene, acetone, methyl ethyl ketone, ethyl acetate, butyl acetate, methanol, ethanol and isopropyl alcohol, and two or more kinds may be combined. Further, if necessary, a curing agent such as a melamine-based curing agent, an epoxy-based curing agent, or an epoxy melamine-based curing agent can be used in combination. Further, the protective resin layer (11) made of the overcoat agent may be a single coat or a multi-coat having two or more layers. On the other hand, examples of the synthetic resin film include a polyester film made of polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate and the like, a polyamide film, and a polyolefin film made of stretched polypropylene and the like, and two or more films of the same type or different types are combined. You may. When the overcoat agent and the synthetic resin film are combined, it is preferable to apply the overcoat agent to the upper surface of the synthetic resin film. The thickness of the entire protective resin layer (11) is not particularly limited, but is usually 1 to 25 μm, preferably 1 to 15 μm in consideration of the protective function of the printed layer (12) and the thermal conductivity at the time of heat sealing.

The degree of external slipperiness of the outermost surface of the protective resin layer (11) in which the lubricant (S) is present can be evaluated by the dynamic friction coefficient (JIS K 7125). This value is not particularly limited, but if it is about 0.05 to 0.5, defects in the print layer (12) are less likely to occur, and fingers are less likely to slip when opening the package (3). Work is also easy. From this point of view, the coefficient of dynamic friction is preferably 0.1 to 0.3.

The amount of the lubricant (S) present on the outermost surface of the protective resin layer (11) is also not particularly limited, but it is usually considered in consideration of the intended external slipperiness and the defect prevention property of the printed layer (12). It is 0.05 to 1.0 μg / cm ² , preferably 0.1 to 0.5 μg / cm ² .

The printed layer (12) is a layer interposed between the protective resin layer (11) and the outer surface side anchor coat layer (13) or the barrier layer (14) described later, and forms characters, figures, and symbols. , Give the lid (1) the information and design of the contents (C) of the package (3). The printing layer (12) may be a continuous layer such as a solid coating, but may be an intermittent layer as shown in FIG. 1, and the latter layer may be gravure printing, offset printing, flexographic printing, or the like. It can be formed by the known printing method of. Further, the print layer (12) may be printed in a single color or may be printed in multiple colors. Further, the printing layer (12) may be a single-layer printing or a multi-layer printing having two or more layers. As the printing ink constituting the printing layer (12), a composition obtained by dispersing a coloring material in various known vehicles made of a binder resin and a solvent by various known means can be used. As the binder resin, for example, it does not cure with active energy rays such as vitrified cotton (nitrocellulose), shellac resin, epoxy resin, polyurethane resin, chlorinated polyolefin resin, polyamide resin, acrylic resin and vinyl chloride-vinyl acetate copolymer. Examples include type binder resins. The active energy ray-curable binder resin has various known di (meth) acrylates, tri (meth) acrylates and tetra (meth) acrylates, and 5 to 6 (meth) acryloyl groups in the molecule (). Examples thereof include poly (meth) acrylates such as meta) acrylate. Further, the poly (meth) acrylates include various known modified poly (meth) acrylates such as urethane (meth) acrylate, epoxy (meth) acrylate and polyester (meth) acrylate. Further, the active energy ray-curable binder resin can be combined with a benzophenone-based initiator, an acetophenone-based initiator, a benzoin-based initiator, or the like as a photopolymerization initiator. Further, the binder resin can be combined with, for example, a polyfunctional isocyanate, a polyfunctional epoxy compound, a polyfunctional oxazoline compound, a ketimine compound, a melamine compound and the like as a curing agent. As the solvent, for example, organic solvents such as toluene, xylene, acetone, methyl ethyl ketone, ethyl acetate, butyl acetate, methanol, ethanol and isopropyl alcohol can be used. When the binder resin is an active energy ray-curable resin, various known (meth) acrylates can be used as the reactive diluent. On the other hand, examples of the coloring material include pigments and / or dyes. Pigments include titanium dioxide, zinc flower, gloss white, parite, barium carbonate, calcium carbonate, precipitated silica, aerodyl, talc, alumina white, mica, synthetic calcium silicate, magnesium carbonate, barium carbonate, carbon black, magnetite and red iron oxide. Examples of organic or inorganic pigments such as the above can be exemplified. Examples of the dye include anthraquinone dyes, azo dyes, quinoline dyes and the like. The content of the colorant in the printing ink is not particularly limited and is usually 0.5 to 40% by weight, but from the viewpoint of ensuring the strength of the printing layer (12) and suppressing internal shedding and internal peeling, 2 to 15 % By weight is preferred. Further, the size of the coloring material is not particularly limited, and in the case of a pigment, the average primary particle size is usually 0.1 to 5 μm, preferably 0.5 to 3 μm. The printing ink may contain, for example, various known silane coupling agents, curing agents, antistatic agents, and the like as additives. The total thickness of the printed layer (12) is not particularly limited, and is usually 0.5 to 2 μm, preferably 0.5 to 1.5 μm per layer.

The outer surface side anchor coat layer (13) is an arbitrary layer formed on the outer surface side surface of the barrier layer (14) as needed, and is a protective resin layer (11) and / or a printed layer (12) and a barrier. By interposing it between the layers (14), the adhesiveness or adhesion between the layers is enhanced, and it becomes easy to prevent delamination. Examples of the anchor coating agent constituting the outer surface side anchor coating layer (13) include nitrified cotton (nitrocellulose), shellac resin, epoxy resin, chlorinated polyolefin resin, polyamide resin, acrylic resin and vinyl chloride-vinyl acetate co-weight. Combined, polyurethane resin and the like can be mentioned. As the anchor coating agent based on the polyurethane resin, a two-component curable polyether-urethane resin adhesive and / or a two-component curable polyester-urethane resin adhesive is preferable, and as the curing agent, for example, polyfunctional isocyanate or A polyfunctional epoxy compound, a polyfunctional oxazoline compound, a ketimine compound and the like can be used in combination. When a resin made of the resin forming the protective resin layer (11) and / or the same or the same type of resin as the binder resin forming the printing ink is selected as the outer surface side anchor coating agent, the outer surface side anchor coating agent layer (13) and / or the same kind of resin are selected. Adhesion to the protective resin layer (11) and / or the printing layer (12) is further improved, and delamination and defects in the printing layer (12) can be easily prevented. The thickness of the outer surface side anchor coat layer (13) is not particularly limited, and is usually 1 to 5 μm. The outer surface side anchor coat layer does not contain the lubricant (S) and the coloring material.

The barrier layer (14) is made of metal leaf and protects the contents (C) from gas, water vapor, light and the like. Examples of the metal foil include aluminum foil, iron foil, stainless steel foil, copper foil, nickel foil and the like, and aluminum foil is suitable in consideration of barrier function, moldability, cost and the like. Examples of the aluminum foil include pure aluminum foil and aluminum alloy foil, which may be either a soft material (O material) or a hard material (H18 material). In particular, the O material of the 1000 series aluminum alloy foil or the O material of the 8000 series aluminum alloy foil specified by JIS H4160 is preferable in terms of moldability, and A1N30H-O, A8021H-O and A8079H-O are particularly preferable. Further, on one side or both sides of the metal foil, a base layer can be formed by using a predetermined chemical conversion treatment liquid for the purpose of improving the adhesive strength at the interface between the metal foils. Examples of the chemical conversion treatment liquid include a water-alcohol solution containing phosphoric acid, a chromium-based compound, a fluorine-based compound and / or a binder resin. Chromic acid and / or chromium (III) salts are used as chromium-based compounds, fluoride metal salts and / or fluoride non-metal salts are used as fluorine-based compounds, and acrylic resins, chitosan derivative resins and chitosan derivative resins are used as binder resins. At least one kind of resin selected from the group consisting of phenolic resins can be exemplified. The amount of the chemical conversion treatment liquid used is not particularly limited, and is usually in the range of 0.1 to 50 mg / m ² for the amount of chromium adhered to one side of the metal foil. The thickness of the barrier layer (14) is not particularly limited, but is usually 5 to 50 μm. Within this range, it becomes easy to prevent cracks due to the generation of pinholes and vibration, and it becomes easy to secure heat transfer property at the time of heat sealing. From this point of view, the thickness is preferably 7 to 35 μm.

The inner surface side anchor coat layer (15) is an arbitrary layer formed on the inner surface side surface of the barrier layer (14) as needed, and the barrier layer (14) and an arbitrary cushioning material layer (16) or heat. By interposing it between the seal layer (17) and the seal layer (17), it becomes easy to improve the adhesion between the layers and prevent delamination. As the anchor coating agent constituting the inner surface side anchor coating layer (15), various known polyurethane resin-based adhesives are preferable in consideration of such adhesiveness. In particular, a two-component curable polyether-polyurethane resin adhesive and / or a two-component curable polyester-polyurethane resin adhesive are suitable, and examples of the curing agent include polyfunctional isocyanates, polyfunctional epoxy compounds, and polyfunctional oxazoline compounds. , Ketimine compounds and the like can be used in combination. The thickness of the inner surface side anchor coat layer (15) is not particularly limited, but is usually 1 to 5 μm, preferably 1 to 3 μm in consideration of the adhesion and delamination.

The cushioning material layer (16) is an arbitrary layer arranged between the barrier layer (14) or the inner surface side anchor coat layer (15) and the heat seal layer (17), and is the package (3) of the present invention. It is possible to prevent cracks in the barrier layer (14) that may occur when an external force such as vibration or impact is applied to the package, and tearing of the lid (1) when the package (3) is opened. The cushioning material layer (16) can be made of various known synthetic resins, and examples thereof include polyolefin resins and polyester resins. Examples of the polyolefin resin include polypropylenes such as homopolypropylene, block polypropylene, random polypropylene and acid-modified polypropylene, polyethylenes such as low-density polyethylene, linear low-density polyethylene and high-density polyethylene, and poly (ethylene-propylene). ) Examples include polyethylene and propylenes such as random copolymers and polyethylene-polypropylene block copolymers. Among the polyolefin resins, polyethylenes are suitable when the heat seal layer (17) is a hot melt adhesive or a multilayer sealant film described later. Further, polypropylene is suitable when the heat seal layer (17) is polypropylene, polyester or the like. Examples of the polyester resin include polyethylene terephthalate resin and polybutylene terephthalate resin. The cushioning material layer (16) may be formed of a film (stretched or unstretched) made of the synthetic resin, but is preferably formed by an extrusion method. The thickness of the cushioning material layer (16) is not particularly limited, but is usually 10 to 50 μm. Within such a range, it becomes easy to prevent the crack of the barrier layer (14) and the tear of the lid (1) described above. From this point of view, the thickness is preferably 25 to 35 μm.

The heat seal layer (17) is a layer that constitutes the lowermost surface of the lid (1) and is heat-sealed with the opening peripheral edge of the container (2), and is a various known heat-sealing resin film and / or hot. Consists of melt adhesive. The thickness of the heat seal layer (17) is not particularly limited, but is usually 10 to 60 μm, preferably 15 to 50 μm in consideration of sealing accuracy and sealing strength.
The heat-sealing resin film may be either a non-stretched film or a stretched film. Examples of the heat-sealing resin include polyolefin resins, polyester resins, polyvinyl resins, polysulfone resins and the like. Examples of the polyolefin resin include polypropylenes such as homopolypropylene, block polypropylene, random polypropylene and acid-modified polypropylene, polyethylenes such as low-density polyethylene, linear low-density polyethylene and high-density polyethylene, and poly (ethylene-propylene). ) Examples include polyethylene and propylenes such as random copolymers and polyethylene-polypropylene block copolymers. Examples of the polyester resin include polyethylene terephthalate resin and polybutylene terephthalate resin. Examples of the polyvinyl resin include polystyrene resin and the like. The heat-bondable resin film may be a combination of two or more of the above constituent resins, and for example, a multilayer film made by co-extruding these resins, or a film made of polypropylene and a film made of polyvinyl resin is arbitrary. Examples thereof include multilayer sealant films that are combined in order. Further, the heat-sealing resin film may contain the above-mentioned lubricant (S) in advance. Specifically, for example, when the heat-sealing resin film is composed of two or more layers, the film forming the innermost surface can be composed of a heat-sealing resin in which a lubricant (S) is kneaded in advance. .. If the modified wax is selected as the lubricant (S), particularly an amide wax, the heat seal layer (17) and the protective resin layer (11) that may occur when the laminate (10) of the present invention is wound and stored in a coiled state. ) And blocking can be suitably prevented. The amount of the lubricant (S) added is not particularly limited, but may be usually 100 ppm to 8000 ppm, preferably 500 ppm to 3000 ppm based on the weight of the heat-sealing resin.
Examples of the hot melt adhesive include a composition containing a base resin and a tackifier resin. Examples of the base resin include a polyolefin resin and an ethylene-vinyl acetate copolymer, examples of the polyolefin resin include those described above, and examples of the vinyl acetate copolymer include an ethylene-ethyl acrylate / vinyl acetate copolymer. The tackifier resin includes rosins such as rosin and / or disproportionate rosin, esters of rosins with polyhydric alcohols such as glycol, glycerin and pentaerythritol, and terpenes and / or styrene as constituent monomers. Examples thereof include hydrocarbon resins. The hot melt adhesive may contain the above-mentioned lubricant (S) in advance. The lubricant (S) is not particularly limited as long as it bleeds out to the innermost surface of the heat seal layer (17) made of a hot melt adhesive, but the wax is preferable, and hydrocarbons among the synthetic waxes are particularly preferable. Synthetic waxes and / or modified waxes are suitable. Specifically, at least one selected from the group consisting of silicon-based wax, paraffin wax, montan wax, polyethylene wax, polypropylene wax, wax obtained by graft-modifying styrene to a polyethylene-polypropylene copolymer, and a composite thereof. Wax is preferable, and according to this, the heat seal layer (17), the protective resin layer (11) and blocking that may occur when the laminated material (10) of the present invention is stored in a roll state can be suitably prevented. Further, various additives can be arbitrarily used, and examples thereof include anti-blocking agents and antistatic agents. The contents of the polyolefin resin, the ethylene-vinyl acetate copolymer, the tackifier resin, the lubricant (S) and the additive in the hot melt adhesive are not particularly limited, and are, for example, 5 to 50% by weight, 10 to 30% by weight, and 15 in order. ~ 30% by weight, 25 ~ 55% by weight and 0-1% by weight (total 100% by weight). The hot melt adhesive can be applied to the barrier layer (14), the inner surface side undercoat layer (15) or the cushioning material layer (16) by using a hot applicator, a gravure coater or the like. Further, instead of the hot melt adhesive, a film-shaped hot melt adhesive may be used, and the lubricant (S) can be contained in this adhesive in advance. Further, the heat-sealing resin film may be combined with the hot-melt adhesive to form the heat-sealing layer (17).
If the heat-sealing layer (17) and the container (2) are made of the same or the same type of synthetic resin, the sealing accuracy and strength are improved, and even if impurities such as dust are attached to the sealing surface, the lid (1) The heat fusion property between the container (2) and the opening peripheral edge (21) of the container (2) is enhanced.

The laminated material (10) can be produced by various known methods such as a dry laminating method, a melt extrusion laminating method, and a heat laminating method, and these methods may be combined. The method for allowing the lubricant (S) to be present on the outermost surface of the protective resin layer (11) forming the laminated material (10) is not particularly limited, and examples thereof include a coating method, a transfer method, and a vapor deposition method.
In the coating method, for example, a lubricant solution obtained by dissolving or dispersing the lubricant (S) in the organic solvent in the coating film or the synthetic resin film made of the overcoat agent forming the outermost surface of the protective resin layer (11). The lubricant (S) can be present on the outermost surface of the protective resin layer (11) by applying the dispersion by a known coating means and volatilizing the organic solvent. Further, when a lubricant (S) in which an appropriate amount of the surfactant is combined with the wax is used, the coatability is improved and the lubricant layer (11S) having a more uniform thickness tends to be easily formed. The coating means is not particularly limited, and examples thereof include a spray coating method, a gravure roll coating method, and a reverse roll coating method. The concentration of the lubricant in the lubricant solution or the dispersion is not particularly limited, but is usually about 500 ppm to 10000 ppm on a weight basis. When the lubricant (S) present on the outermost surface of the protective resin layer (11) forms a dispersed phase, an intermittent lubricant layer (11S) as conceived in FIG. 1 (a) can be formed. .. Further, when the lubricant (S) forms a continuous phase, a continuous lubricant layer (11S) as conceived in FIG. 1 (b) can be formed.
In the transfer method, for example, a laminated material (10) formed by forming a heat-sealing layer (17) with the heat-sealing resin preliminarily containing a lubricant (S) is formed on the inside of the heat-sealing layer (17). A single coil in which the heat seal layer (17) and the protective resin layer (11) are in close contact with each other as shown in Fig. 2 (b) by continuously winding them around an appropriate core material. (Roll) is made once. Next, the coil is left at a predetermined temperature for a predetermined time and aged to bleed out the lubricant (S) to the innermost surface of the heat seal layer (17). Then, the lubricant (S) thus precipitated is transferred to or transferred to the outermost surface of the protective resin layer (11) which is in close contact with the heat seal layer (17), and the type of the lubricant (S). The heat seal layer (17) and the protective resin layer are shown in FIG. 2 (a), although it depends on the combination of the lubricant (S) and the heat-sealing resin forming the heat seal layer (17) and the aging conditions. It is considered that a lubricant layer (11S) is formed at the interface of (11). The lubricant layer (11S) may be a continuous phase or a dispersed phase. On the other hand, in the laminated lumber (10) after rewinding the coil, the lubricant (S) is present on the outermost surface of the protective resin layer (11) and the innermost part of the heat seal layer (17). As shown in FIG. 2 (c), it is considered that the bleed-out lubricant (S) remains on the surface. The transfer method can be performed without producing a coil. Specifically, for example, a plurality of rectangular laminated lumbers (10) are prepared, and the heat seal layer (17) and the protective resin layer (11) are overlapped so as to be in contact with each other, and then a weight of a predetermined weight is applied from above. The lubricant (S) can also be present on the outermost surface of the protective resin layer (11) by placing and aging the protective resin layer (11). In either method, as the lubricant (S) contained in the heat seal layer (17), for example, a silicon wax, a polyethylene wax, or an amide wax is suitable. The aging conditions are not particularly limited, and may be, for example, room temperature to about 70 ° C. and about 1 to 15 days.
In the vapor deposition method, for example, the lubricant (S) may be heated and vaporized in a vacuum chamber to be vapor-deposited as cluster molecules on the outermost surface of the protective resin layer (11). In this embodiment, a lubricant layer (11S) consisting of a continuous single layer can be easily formed as shown in FIG. 1 (b).
The above methods may be a combination of two or more. Specifically, for example, the outermost surface of the protective resin layer (11) of the laminated material (10) in which the lubricant (S) is preliminarily contained in the heat seal layer (17) is the same as or on the outermost surface of the lubricant (S). A lubricant layer (11S) made of a different lubricant (S) is formed in advance by the coating method, and by carrying out the transfer method, a heat seal layer (17) is formed on the outermost surface of the protective resin layer (11). ) Can be transferred to the lubricant (S) contained in it. In this case, the final lubricant layer (11S) can be said to be a composite layer in which the morphology based on the coating method and the morphology based on the transfer method are mixed.
If the lubricant (S) present on the protective resin layer (11) contains wax, place the laminate (10) at a temperature above its melting point and apply the lubricant (S) partially or entirely. It is also possible to wet and spread the outermost surface of the protective resin layer (11) by melting it into the lid (1) to improve the external slipperiness of the lid (1).

The lid (1) is a processed laminated material (10), and its size and shape are not particularly limited, and can be appropriately determined according to the shape of the container (2) and the opening style of the package (3). Specifically, as shown in FIG. 2A, when the container (2) has a cup shape with an upper opening and the opening peripheral portion (21) has a substantially horizontal flange shape, the lid (1) ) May be a single-wafer-shaped member made of the main body (1a), and can form an opening hook such as a tab or a notch as needed. Further, as shown in FIG. 2 (b), when the container (2) has a bottle shape with an upper opening and the opening peripheral portion (21) has a rim shape, the lid (1) is shown in FIG. 3 (1). b) and the cap shape as shown in FIG. 4 may be used.

FIG. 4 is a perspective view of a cap-shaped lid (1), in which the lid (1) has a main body portion (1a) and a skirt portion (1b) extending in a hanging shape from the peripheral edge of the main body portion (1a). Consists of. Although not shown, even if the container (2) has a bottle shape as shown in FIG. 3 (b), the opening peripheral edge portion (21) can be formed in a flange shape, and in this case as well. A skirt portion (1b) may be formed on the lid (1). Also, although not shown, the container (2) may be a container for a press-through pack (PTP), and in this case, the lid (1) is a sheet-like member composed of the main body (1a). Can be.

FIG. 5 is a conceptual diagram of a method for evaluating the external slipperiness of the protective resin layer (11) forming the lid (1) (laminated material (10)). The device (4) in this figure includes a horizontal table (41) on which the lid (1) of the present invention is placed, a metal support column (42) arranged above the protective resin layer (11), and a support column ( It is composed of a metal spherical terminal (43) connected to the bottom surface of 42), and the surface of the spherical terminal (43) is covered with cotton gauze (not shown). Further, in this figure, the lid (1) is composed of only the protective resin layer (11), the printing layer (12) and the barrier layer (14) for convenience. The details of the evaluation method will be described in Examples.

The material of the container (2) is selected according to the heat-sealing property with the lid (1) and the properties of the content (C). As the material, the heat-sealing resin film constituting the heat seal layer (17) or the same or the same type of resin as the hot melt adhesive is preferable, but glass, iron, copper, aluminum and the like can also be used. In particular, if the opening peripheral edge (21) of the container (2) is formed of a heat-sealing resin and the heat-sealing layer (17) of the lid (1) is also made of the same or the same type of heat-sealing resin, the package is packaged. The sealing accuracy and strength of the body (3) are improved, and the sealing property is improved. The shape of the container (2) is not particularly limited, and examples thereof include a cup shape, a bottle shape, and a cylindrical shape. When the container (2) has a bottle shape, if the neck portion has a tapered shape as shown in FIG. 3 (b), stable sealing is possible. The manufacturing method of the container (2) is not particularly limited, and examples thereof include deep drawing, blow molding, vacuum forming, and pressure air forming.

The content (C) is not particularly limited, and examples thereof include products that are orally ingested. Specific examples thereof include solid or liquid food products such as dairy products, milk drinks, soft drinks, ham, cheese, curry, and sauces, and liquid or solid pharmaceutical products. In addition, hygiene products such as napkins, gauze, and cotton can be sufficient as the contents (C).

The package (3) is a container (2) filled with the contents (C), and the lid (1) of the present invention is heat-sealed by heat-sealing using various known sealing devices. The sealing conditions are not particularly limited, and are appropriately determined according to the material type of the lid (1) and the container (2), the specifications of the sealing device, and the like.

FIG. 6 is a conceptual diagram of a method for directly evaluating the external slipperiness of the protective resin layer (11) in the lid (1) of the package (3). The device (5) in this figure consists of a packaging material (51) such as corrugated cardboard and a plurality of samples (52) housed therein. Each sample (52) is a braid in which two packages (3) are connected in the lateral direction and restrained by a binding film (53) such as a polyethylene film from the side surface. The number of samples (52) is not particularly limited, and may be appropriately determined according to the dimensions of the packaging material (51) and the size of the packaging body (3). In this figure, three sets of samples are laminated in the vertical direction via a partition material (54). As the partition material (54), for example, a material having an uneven surface and having a certain strength, such as corrugated cardboard, can be used. However, the partition material (54) is optional and can be omitted. The details of the evaluation method will be described in Examples.

Hereinafter, the present invention will be described in more detail through Examples and Comparative Examples, but the technical scope of the present invention is not limited by these specific examples.

<Making the lid (1)>
Example 1
10% by weight of white pigment (titanium dioxide) is dispersed in a commercially available vinyl chloride-vinyl acetate copolymer anchor coating agent on one side of a 25 μm thick aluminum foil, which is an A8079H-O material specified by JIS H4160. The white ink was applied with a gravure roll so that the coating film thickness was about 1.5 μm to form a print layer. Next, an ethyl acetate solution of nitricized cotton (nonvolatile content: 10% by weight) was applied to the surface of this printed layer and dried to form a protective resin layer having a thickness of 2 μm to prepare an intermediate member. Next, a commercially available two-component curable polyester polyurethane adhesive was applied to the other surface of the aluminum foil of the intermediate member to form an inner surface side anchor coat layer having a thickness of 2 μm. Next, a lubricant-containing unstretched polypropylene film (main component: polypropylene resin (random copolymer), lubricant: erucic acid amide (1000 ppm)) having a thickness of 40 μm was bonded to the inner surface side anchor coat layer to form a heat seal layer. , Laminated material A ₀ was prepared. Next, the laminated material A ₀ is wound so that the heat seal layer is on the inside to prepare a coil, and the coil is aged at 40 ° C. for 10 days to bleed the lubricant on the innermost surface of the heat seal layer. At the same time as it was taken out, it was transferred to the outermost surface of the protective resin layer. Then, by rewinding this coil, the laminated lumber A according to the present invention was prepared. The coefficient of dynamic friction of the protective resin layer of laminated lumber A was measured in accordance with JIS K7125 (hereinafter, the same applies) and found to be 0.25.

Example 2
The same intermediate member as that produced in Example 1 was prepared, and a commercially available two-component curable polyester polyurethane adhesive was applied to the other surface of the aluminum foil to form an inner surface side anchor coat layer having a thickness of 2 μm. Formed. Next, low-density polyethylene was extruded into the inner surface side anchor coat layer to form a cushioning material layer having a thickness of 30 μm. Next, a hot melt adhesive was applied to the cushioning material layer with a gravure roll so as to have a thickness of 20 μm, and then cooled to form a heat seal layer to prepare a laminated material B ₀ . The composition of this hot melt adhesive is ethylene / ethyl acrylate / vinyl acetate copolymer (13% by weight), polyethylene resin (melting point 95 ° C) (31% by weight), silicon wax and polyethylene wax (45% by weight in total), It was a tackifier (10% by weight) and an additive containing an anti-blocking agent (1% by weight) (100% by weight in total). Next, the laminated material B ₀ is wound so that the heat seal layer is on the inside to prepare a coil, and the coil is aged at 40 ° C. for 10 days to bleed the lubricant on the innermost surface of the heat seal layer. At the same time as it was taken out, it was transferred to the outermost surface of the protective resin layer. Then, by rewinding this coil, the laminated lumber B according to the present invention was prepared. The coefficient of dynamic friction of the protective resin layer of the laminated lumber B was 0.45.

Example 3
The same intermediate member as that produced in Example 1 was prepared, and a commercially available two-component curable polyester polyurethane adhesive was applied to the other surface of the aluminum foil to form an inner surface side anchor coat layer having a thickness of 2 μm. Formed. Next, low-density polyethylene was extruded into the inner surface side anchor coat layer to form a cushioning material layer having a thickness of 30 μm. Next, an unstretched polypropylene film (main component: polypropylene resin (random copolymer)) having a thickness of 40 μm containing no lubricant was attached to this cushioning material layer to form a heat-sealing layer, and then at 40 ° C. for 10 days. Laminated material C ₀ was produced by aging. Next, the present invention was carried out by spraying a methyl ethyl ketone solution containing 1000 ppm of polyethylene wax on the outermost surface of the protective resin layer of the laminated material C ₀ on a weight basis, gently wiping with a felt cloth, and drying at 120 ° C. for 1 minute. The laminated material C according to the above was prepared. The coefficient of dynamic friction of the protective resin layer of the laminated lumber C was 0.07.

Comparative Example The laminated materials A ₀ , B ₀ and C ₀ all use a common intermediate member, and no lubricant is present on the outermost surface of the protective resin layer forming the intermediate member. , The laminated material A ₀ was represented as a comparative example. The dynamic friction coefficient of the protective resin layer of the laminated material A ₀ was 1.2.

<Measurement of lubricant abundance>
50 test pieces A1 (10 cm x 10 cm) were prepared from the laminated material A. Next, one test piece A1 was weighed with an electronic balance (Shinko Denshi Co., Ltd., HTR-220), the surface of the protective resin layer was wiped off with a non-woven fabric impregnated with ethanol, and then weighed again. Next, the weight difference (μg) of the test piece A1 was divided by the area of the test piece (100 cm ² ) to determine the abundance of lubricant (μg / cm ² ). In addition, the abundance of lubricant (μg / cm ² ) was determined in the same manner for each of the other 49 test pieces A1. Then, by dividing the total value of the lubricant abundance for all 50 sheets by the total number of test pieces (50 sheets), the lubricant abundance on the outermost surface of the protective resin layer of the laminated lumber A is obtained as an average value. As a result, it was 0.28 μg / cm ² . The same average value was obtained for the laminated materials B and C in the same manner. The results are shown in Table 1.

<Evaluation of external slipperiness of laminated lumber for lids (Test 1)>
A test piece A2 (5 cm x 20 cm) was cut out from the laminated material A, placed on a stainless steel horizontal support base, and fixed with adhesive tape on all four sides. Next, a predetermined sliding member was installed on the upper surface of the test piece A2. This sliding member was a jig with a total weight of 1 kg as shown in FIG. 5, and the diameter of the spherical terminal (SUS304) was 10 mm. In addition, this spherical terminal was covered with cotton gauze. Then, by lowering the sliding member, the spherical terminal was lightly pressed against the protective resin layer via cotton gauze. Next, this member was moved in the left-right direction so that the reciprocating distance was 2 cm / sec, and slid until the appearance of the printed layer changed, such as blurring on the printed surface. The maximum number of round trips was 30. The evaluation is poor (×) if the number of round trips until the change occurs is within 1 to 10 times, slightly good (△) if it is 11 to 20 times, and good (○) if it is within 21 to 30 times. ). As a result, the test piece A2 was 30 times, which was good (○). The same test was performed on the test pieces B, C and A ₀ . The results are shown in Table 1.

<Making a package, evaluating the external slipperiness of the lid (Test 2)>
A lid A (80 mm × 80 mm) having a predetermined size was cut out from the laminated lumber A. Next, put 54 cc of water in a cup-shaped container (diameter 66 mmφ, bottom diameter 57 mmφ, height 26 mm, flange width 7 mm) made of polystyrene resin and having a predetermined size, and cover the opening with the lid A as its heat seal layer. A sealed package A was prepared by covering from the side and pressing a stainless steel plate heated to 150 ° C. from the top for 1.0 second. Further, 23 more packages A were prepared by the same method. Next, the two packages A were arranged on a horizontal table, and with the flange portions in contact with each other, a polyethylene film was wound from the side surface and bound to prepare a set of samples. Eleven more samples were prepared in the same manner. Next, as shown in FIG. 6, a total of three sets of the samples are arranged on the bottom surface of a cardboard box (length 11 cm × width 24 cm × depth 19 cm) having a predetermined size, and a cardboard with a thickness of 1 mm is placed on the upper surface of the lid as a partition material. A sheet (24 cm × 19 cm) was placed, and a total of three sets of the samples were arranged on the sheet. This operation was repeated, and a total of 12 sets of the samples were packed. Next, after packing this cardboard box with adhesive tape, it was shaken under a predetermined condition (120 rpm, amplitude 50 mm) for 100 hours through a commercially available shaking device (manufactured by Yamato Scientific Co., Ltd., SA31). Next, the cardboard box was unpacked, the upper surface of the lid was visually judged for all 24 packages A, and the peeled portion of the print layer was counted for each. The evaluation was good (○) when the number of peeled parts was 0 to 2, slightly good (Δ) when the number was 3 to 10, and defective (×) when the number was 11 or more. As a result, the number of peeled parts of the package A was 0, which was good (◯). Packagings B, C and A ₀ were prepared in the same manner for the laminated materials B, C and A ₀ , and the external slipperiness of the lids B, C and A ₀ was evaluated by the same method. The results are shown in Table 1.

The laminated material for a lid of the present invention is suitable as a lid for heat-sealing a container containing food or other articles, and even if an unexpected external force is applied to the protective resin layer during transportation or display, it can be applied to the printing layer. It has high economic value because it is unlikely to cause defects such as peeling and misalignment.

(10) Laminated material for lid, (S) Lubricating material, (11S) Lubricating layer, (11) Protective resin layer, (12) Printing layer, (13) Outer surface side anchor coat layer, (14) Barrier layer, (15) Inner surface side anchor coat layer, (16) cushioning material layer, (17) heat seal layer, (1) lid, (2) container, (21) opening peripheral edge, (C) contents, (3) package, ( 4) External slip evaluation device, (5) External slip evaluation device

Claims (5)

A laminated material for a lid that is heat-sealed to the peripheral edge of the opening so as to cover the opening of the container filled with the contents.
From the outside,
With a protective resin layer,
With the print layer,
A barrier layer made of metal leaf and
It has a heat seal layer made of a thermoplastic resin and has.
and,
A lubricant is present on the outermost surface of the protective resin layer.
Laminated material for lids. The laminate for a lid according to claim 1, wherein the thermoplastic resin forming the heat seal layer contains a lubricant. The laminated lumber for a lid according to claim 1 or 2, wherein the outermost surface of the protective resin layer in which the lubricant is present has a coefficient of dynamic friction of 0.05 to 0.5. The laminate for a lid according to any one of claims 1 to 3, wherein the amount of the lubricant present on the outermost surface of the protective resin layer is 0.05 to 1.0 μg / cm ² . A package in which a lid made of the laminate for a lid according to any one of claims 1 to 4 is heat-sealed to the peripheral edge of an opening of a container filled with the contents.

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