JP2023158853A - Paper container with peelably applied film and manufacturing method thereof - Google Patents

Abstract

To provide a paper container in which a film can be readily peeled off from a paper base material, and a manufacturing method thereof.SOLUTION: A paper container of the present invention is produced by partially overlapping a paper base material to which a film is attached so as to form a storage space that can accommodate stored items, and thermally welding an overlapped portion using a heat sealing agent. A film 3 is peelably attached to the paper base material by thermal welding using the heat sealing agent 4 that is applied on the film 3 in a predetermined pattern.SELECTED DRAWING: Figure 3

Description

The present invention relates to a paper container in which a film is releasably attached to a paper base material, and a method for manufacturing the same.
The container here refers to one formed by thermally welding a paper base material to which a film is releasably attached and a heat-sealing portion coated with a heat-sealing agent. This container may have a printed layer of letters, patterns, etc. formed with ink, etc., and may be, for example, a bag-shaped container for storing food or daily necessities, or a box-shaped container to maintain its shape. This applies to items used for various purposes (such as various disposable daily necessities).

Conventionally, a sheet material is used, in which a heat-sealing layer made of thermoplastic resin material such as polypropylene or polyethylene is laminated by extrusion molding on a plastic base material, and the sheets are partially overlapped and heat-welded to produce storage bags, storage containers, etc. (hereinafter referred to as a containment body) is known. Such containers are used to store various items such as food and daily necessities, but in recent years, due to environmental concerns, the base material has been changed from plastic to paper. ing.

Containers made of such paper base materials can be used in the food field, etc. However, if the base material is made of paper, especially if the stored contents are liquid, the liquid may be made of paper. A situation may also occur in which the adhesive penetrates into the base material and shows through. Therefore, a film is applied to the surface of a paper base material to prevent such penetration. Such a film not only prevents liquid from penetrating into the paper base material, but also has deodorizing and humidity controlling effects, and can also function as a gas barrier (see, for example, Patent Documents 1 to 3).

JP 2021-155044 Publication Japanese Patent Application Publication No. 2018-176441 Japanese Patent Application Publication No. 2004-051099

Incidentally, recently, there has been a demand for a film that can be peeled off from a paper base material from the viewpoint of sorting for disposal. However, the film is often adhered to a paper base material with strong adhesion, and therefore there is a problem in that it is difficult to peel off (difficult to separate) the film from the paper base material. Therefore, there is still room for improvement in the art regarding the ease of peeling of films from paper substrates.

The present invention was made in view of the above-mentioned problems, and an object of the present invention is to provide a paper container from which a film can be easily peeled off from a paper base material, and a method for manufacturing the same.

In order to achieve the above object, the present invention provides a method for producing a paper container in which a film is releasably attached to a paper base material, the method comprising: A heat sealing agent is applied to at least one side in a predetermined pattern, and the film is attached to a paper base material by thermal welding using the applied heat sealing agent to form a storage space that can accommodate the stored items. Preferably, the paper base material to which the film is attached is partially overlapped, and the overlapping portion is thermally welded using a heat sealing agent to form the container.

In the above configuration, a heat sealing agent is applied to the paper base material and/or film in a predetermined pattern so that the film can be peeled off from the paper base material. In addition to removably attaching the film, a heat-sealing agent is also used to thermally weld the overlapped portions of the film-covered paper base material to form a container having a storage space. ing. That is, by applying a heat sealant in a predetermined pattern onto a paper base material or film, it becomes possible to easily peel off the film from the paper base material.

In the above configuration, there are various possible patterns for applying the heat sealant onto the paper base material or film, but any pattern that allows the film to be easily removed from the paper base material may be used. , any pattern is acceptable. For example, the heat sealing agent applied to a paper base material or film may be applied in a dispersed manner that allows the film to be removed from the paper base material, and may be applied in a pattern such as dots, lines, or grids; A combination of these may be applied, and especially when the film has elasticity, it is preferable to apply it in a pattern that can follow the expansion and contraction. Alternatively, the heat sealing agent applied to the paper base material or film may be applied at a concentration that allows the film to be peeled from the paper base material. In any case, by adjusting the dispersion mode or concentration of the heat sealant (by changing the spacing between dots or lines of the heat sealant, or by making the concentration thinner or thicker), it is possible to easily convert the film from the paper base material. It becomes possible to freely set the adhesion strength of the film to the paper base material depending on the use and shape of the paper container while enabling easy peeling.

In the above configuration, the heat sealing agent may be a resin material such as polypropylene or polyethylene, but in consideration of the environment, it is preferable to use a water-based material (water-based resin), specifically, a water-soluble type. It is preferable to use a water-based resin, a water-dispersible water-based resin, or the like.

In the above configuration, the film to which the heat sealing agent is applied may be a stretch film, an unstretched film (for example, unstretched polypropylene (CPP), polybutylene terephthalate (PBT), etc.), polyethylene terephthalate (PET), Examples include films such as axially oriented polypropylene (OPP) and vapor-deposited films, paper films, and nonwoven fabrics. Such a film not only functions as a protective film that protects the surface, but also has the effect of preventing liquid penetration into the paper base material (water and oil resistance), deodorizing effect, and humidity control effect, and also acts as a gas barrier. can also work.

As mentioned above, containers formed by thermally welding the polymerized parts of the paper base material to which the film is attached using a heat sealant include, for example, molded paper products, large paper cups, deep-drawn Examples include paper containers and paperboard molded products. Such a container may have a printed layer of letters, patterns, etc. formed with ink or the like, and may be, for example, a bag-shaped container for storing food or daily necessities, or a box-shaped container that retains its shape. This applies to items that are used for maintenance purposes (for example, various disposable daily necessities).

Furthermore, in the above configuration, examples of coating methods for applying (printing) the heat sealant to the film (or the paper base material) include gravure printing coating method, water-based flexo coating method, etc. Examples include coating methods, roll coaters, chamber coaters, and other coaters (for example, air coaters, air knives, shells, etc.).

The present invention also provides a paper container in which a film is adhered to a paper base material as described above.

According to the paper container and the manufacturing method thereof of the present invention, a heat sealing agent is coated on the paper base material or film in a predetermined pattern so that the film can be peeled off from the paper base material. Since the film is attached to the paper base material using the paper base material, the film can be easily peeled off from the paper base material.

A schematic side sectional view of a paper board covered with a film. FIG. 2 is a schematic configuration diagram showing an example of a coater that applies a heat sealant to a film. The patterns of the heat sealant applied on the film are shown: (a) is a random or regular dot pattern, (b) is a linear pattern (horizontal stripe) extending in the horizontal direction, and (c) is a pattern extending in the vertical direction. FIG. 3 is a diagram showing an example of a linear pattern (vertical stripe). The patterns of the heat sealant applied on the film are shown: (a) is a curved pattern extending in the vertical direction, (b) is a grid pattern, and (c) is a pattern in which the heat sealant is applied over the entire film with varying concentrations. FIG. 4 is a diagram showing an example of applied solid pattern. FIG. 3A is a diagram showing an example of a paper container to which a film is removably attached, in which (a) shows a dish-shaped container with a shallow storage space, and FIG. 3(b) shows a cup-shaped container with a deep storage space. FIG. 1 is a block diagram showing an example of a process of a manufacturing apparatus for carrying out a method for manufacturing a paper container according to the present invention.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a schematic side sectional view of a paper board 1. FIG. As shown in the figure, this plate material 1 is constructed by adhering (pasting) a film 3 onto a paper base material (also referred to as a paper base material) 2 by thermal welding using a heat sealing agent 4. . In the present embodiment, such a plate material 1 is formed by, for example, a molding process, and the overlapping portion where the plate materials 1 are partially overlapped is thermally welded with a heat sealing agent, thereby creating a storage space as described later. A container is formed having: Note that the plate material 1 may be formed into a flat plate shape or may be wound into a roll shape.

The paper base material 2 is thick paper, specifically, a paper with a weight of 180 g/m ² or more is used in consideration of shape retention when processed into a container. Further, the specific material constituting the paper is not particularly limited, and for example, vegetable natural fibers, animal natural fibers, chemical fibers, etc. may be used. That is, the thickness and material can be changed as appropriate depending on the container used. Therefore, depending on the application, thin paper smaller than 180 g/m ² may be used.

The materials used for the film 3 include stretch films, unstretched films (for example, unstretched polypropylene (CPP), polybutylene terephthalate (PBT), etc.), polyethylene terephthalate (PET), biaxially oriented polypropylene (OPP), and vapor-deposited films. , paper films, and nonwoven fabrics. Such a film not only functions as a protective film that protects the surface, but also has the effect of preventing liquid penetration into the paper base material (water and oil resistance), deodorizing effect, and humidity control effect, and also acts as a gas barrier. can also work.

The heat sealing agent 4 for attaching the film 3 to the paper base material 2 may be a resin material such as polypropylene or polyethylene, but in consideration of the environment, it may be a water-based material (water-based resin). ) is preferably used. Specifically, water-soluble water-based resins, water-dispersible water-based resins, etc. can be used. As the resin material to be water-based, for example, acrylic resin, polyurethane resin, polyester resin, epoxy resin, ionomer resin, etc. can be used, and these can be dispersed in an aqueous medium (dispersion type) or emulsified. (emulsion type) is applied to the film 3 as a heat sealant 4. Various general-purpose water-based heat sealants 3 can be used, but an appropriate one may be selected and used depending on the material, weight (fabric weight), etc. of the film 3. .

Further, in this embodiment, the heat sealing agent 4 is applied on the film 3 in a predetermined pattern, and the film 3 coated with the heat sealing agent 4 is attached to the paper base material 2. In this case, a lamination procedure may be used in which the heat sealant 4 is applied to the paper base material 2 in a predetermined pattern and then the film 3 is attached. That is, the heat sealing agent may be applied to the paper base material or both.

Specifically, in this embodiment, the heat sealant 4 is applied onto the film 3 in a predetermined pattern so that the film 3 can be easily peeled off from the paper base material 2. Various forms can be considered as patterns for applying the heat sealant 4 onto the film 3, but any pattern may be used as long as the film 3 can be easily peeled off from the paper base material 2. good.

For example, the heat sealing agent 4 may be applied onto the film 3 in a dispersed manner such that the film 3 can be easily peeled off from the paper base material 2. As such a dispersion mode, for example, a mode as shown in FIG. 3 can be considered. That is, in FIG. 3(a), the heat sealant 4 is applied on the film 3 in a random or regular dot pattern. In (a) of FIG. 3, the interval between the dots of the heat sealant 4 becomes narrower from the top to the bottom, and the narrower the interval between the dots, the stronger the adhesion of the film 3 to the paper base material 2. becomes stronger.

Further, in FIG. 3(b), the heat sealing agent 4 is applied on the film 3 in a linear pattern (horizontal stripe) extending in the horizontal direction. In FIG. 3(b), the distance between the lines of the heat sealant 4 becomes narrower from the top to the bottom, and the narrower the distance between the lines, the stronger the adhesion of the film 3 to the paper base material 2. becomes stronger.

Further, in FIG. 3C, the heat sealing agent 4 is applied onto the film 3 in a linear pattern (vertical stripes) extending in the vertical direction. In FIG. 3(c), the distance between the lines of the heat sealant 4 becomes narrower from the top to the bottom, and the narrower the distance between the lines, the stronger the adhesion of the film 3 to the paper base material 2. becomes stronger.

Alternatively, for example, as shown in FIG. 4(a), the heat sealant 4 may be applied onto the film 3 in a curved pattern extending in the vertical direction. In this case as well, the distance between the lines of the heat sealant 4 becomes narrower from the top to the bottom, but the narrower the distance between the lines, the stronger the adhesion strength of the film 3 to the paper base material 2. Become.

Alternatively, as shown in FIG. 4(b), the heat sealant 4 may be applied on the film 3 in a grid pattern. The finer the grid, the stronger the adhesion strength of the film 3 to the paper base material 2.

In either pattern, if the film 3 is made of a stretchable material, it is preferable that the heat sealant 4 is applied onto the film 3 in a pattern that can follow the stretch.

Further, the heat sealing agent 4 applied onto the film 3 is applied at a concentration such that the film 3 can be easily peeled off from the paper base material 2, as shown in FIG. 4(c). Good too. In FIG. 4(c), the concentration of the heat sealing agent 4 increases from the top to the bottom, and the higher the concentration, the stronger the adhesion strength of the film 3 to the paper base material 2 becomes.

The above application form of the heat sealant 4 is just an example, but in this way, the dispersion mode or concentration of the heat sealant 4 can be adjusted (by changing the interval between dots or lines of the heat sealant 4, or , thinner or thicker), the film 3 can be easily peeled off from the paper base material 2. That is, depending on the purpose and shape of the paper container, the adhesion strength of the film 3 to the paper base material 2 can be freely set by changing the printing pattern of the heat sealant.

FIG. 2 schematically shows an example of a coater 60 for applying the heat sealant 4 to the film 3. This coater 60 copies a pattern, etc., which is the application pattern of the heat sealant 4 described above, onto a rubber roller (plate cylinder) 64, rotates the rubber roller 64, and transfers the film 3 being conveyed between the rubber roller 64 and the impression cylinder 65. It is designed to be applied by feeding it into the nip between the parts.

There are two types of coater 60: a roll coater type and a chamber coater type, and either type may be used, but in this embodiment, a chamber coater type is used, which allows easy adjustment of the coating amount. The coater 60 is installed in a chamber (not shown).

The coater 60 that feeds the heat sealing agent 4 to the film 3 being conveyed has a supply section 61 that supplies the heat sealing agent 4, a storage section 62 that stores the supplied heat sealing agent 4, and a storage section 62 that stores the heat sealing agent 4. An anilox roll 63 to which the heated heat sealing agent 4 is attached while rotating, a rubber roller 64 which rotates in contact with the anilox roll 63, and an impression cylinder 65 which comes into pressure contact with the rubber roller 64 are provided. The film 3 is conveyed from a film supply bracket (not shown) while passing through a nip between a rubber roller 64 and an impression cylinder 65 that is in pressure contact with the rubber roller 64.

A large number of fine cells 63a are formed on the surface of the anilox roll 63, and as the anilox roll 63 rotates, the heat sealing agent 4 stored in the storage section 62 is held in the cells 63a and is directly transferred to the The applied pattern of the heat sealant 4 is transferred onto the surface of the rubber roller 64. Further, the heat sealing agent 4 transferred to the surface of the rubber roller 64 is pressed against the surface of the film 3 by the impression cylinder 65, thereby forming a heat sealing layer on the surface of the film 3 in the coating pattern described above. .

The storage portion 62 is provided with blades 66a and 66b that scrape off the heat sealing agent 4 held in the cells 63a when the anilox roll 63 rotates to equalize the amount held. Such blades 66a and 66b prevent the heat sealing agent 4 from leaking from the chamber described above, and make it possible to make the thickness of the heat sealing layer uniform. The heat sealing agent 4 scraped off by the blades 66a and 66b is received by a tray 67.

In the above configuration, it is possible to adjust the thickness of the heat seal layer as appropriate depending on the configuration (depth, density, etc.) of the cells 63a. Further, the film thickness can also be adjusted by adjusting the amount of rotation of each roll, the viscosity of the heat sealant, etc. In this case, it is preferable to apply the heat sealing agent 4 to at least the surface of the film 3 in an amount of 1 to 5 g/m ² to ensure sufficient heat sealability.

Further, it is preferable that a dryer 70 be installed downstream of the coater 60 described above to dry the film 3 coated with the heat sealing agent 4. If the heat sealing agent 4 printed on the surface of the film 3 is water-based, it will be possible to develop stable sealing strength by drying it immediately after printing.

FIG. 6 shows a schematic configuration of a manufacturing apparatus 80 for manufacturing a paper container using the above plate material 1 in which the film 3 is adhered to the paper base material 2 via the heat sealing agent 4. has been done.
In manufacturing using such a manufacturing apparatus 80, the paper base material 2 is first supplied from the paper feeding section 50. In this embodiment, the paper base material 2 is cut into a size according to the product (container) to be finally used, for example, and the paper feed section 50 feeds the cut base material 2. The sheets are fed out one by one from a laminate in which a predetermined number of sheets are stacked. In this case, the base material 2 may be fed out from a roll-shaped original fabric like a general coating machine.

Next, the paper base material 2 fed out from the paper feed section 50 is subjected to predetermined printing in a printing section (for example, a gravure printing machine) 52, and then a film 3 is attached and detached thereon in a film overlapping section 54. superimposed on In this film polymerization section 54, the film 3 on which the heat sealing agent 4 has already been applied in a predetermined pattern using the coater 60 or the like is prepared, as described above, and the film 3 is coated on a paper base using negative pressure, for example. Pull it onto Material 2 and overlap it. Thereafter, the paper base material 2 on which the film 3 is laminated in this manner is fed into the heat welding section 56 and heated, thereby melting the heat sealing agent 4 and easily bonding the film 3 and the paper base material 2 together. It is heat welded so that it can be peeled off.

The plate material 1 with the film 3 and the paper base material 2 heat-welded in this way is finally sent to the molding section 58, where they are partially overlapped by a molding process or the like. The polymerized parts are thermally welded using a heat sealing agent to form various containers.

For example, it is possible to form containers 90A and 90B having storage spaces S as shown in FIG. 5 as an example. 5A shows a dish-shaped container 90A with a shallow storage space S, and FIG. 5B shows a cup-shaped container 90B with a deep storage space S.

As described above, according to the present embodiment, the heat sealing agent 4 is applied on the film 3 in a predetermined pattern so that the film 3 can be easily peeled off from the paper base material 2. A film 3 is attached to the film 2, and a paper base material with a film (board material 1) is partially overlapped and thermally welded to the overlapping part using a heat sealing agent to form a housing having a housing space S. I try to form my body.

That is, the heat sealing agent is not only used for thermally welding the polymerized portion of the base material, but also applied to the film 3 in a predetermined pattern and used for pasting the film 3 to the paper base material 2. Therefore, a laminated structure in which the film 3 can be easily peeled off from the paper base material 2 can be realized using existing components and manufacturing machines without requiring additional components or manufacturing machines.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be implemented with various modifications without departing from the gist thereof.
For example, the application pattern of the heat sealant is not limited to the above-mentioned pattern, and various printing patterns such as straight lines and curved lines, dot patterns, etc. can be used. Further, the materials of the film, paper base material, and heat sealing agent can also be arbitrarily set.

1 Board material 2 Paper base material 3 Film 4 Heat sealing agent 90A, 90B Container S Container space

Claims (6)

A method for producing a paper container in which a film is releasably attached to a paper base material, the method comprising:
Applying a heat sealing agent to at least one of the paper base material and the film in a predetermined pattern,
Attaching the film to a paper base material by thermal welding using the applied heat sealing agent,
The paper base materials to which the film is attached are partially overlapped so as to form a storage space that can accommodate the stored items, and the overlapping portions are thermally welded using a heat sealing agent. form the body,
A method for manufacturing a paper container, characterized in that: The heat sealing agent applied to at least one of the paper base material and the film is dispersed in a dotted, linear, or lattice-like manner so that the film can be peeled off from the paper base material. 2. The method for manufacturing a paper container according to claim 1, wherein the coating is applied in at least one pattern. Claim 1, wherein the heat sealing agent applied to at least one of the paper base material and the film is applied at a concentration that allows the film to be peeled from the paper base material. A method for producing a paper container according to . A paper container on which a film is releasably attached,
It is formed by partially overlapping paper base materials to which a film is attached so as to form a storage space that can accommodate stored items, and thermally welding the overlapped portion using a heat sealing agent,
The film is attached to the paper base material by thermal welding using a heat sealing agent applied in a predetermined pattern to at least one of the paper base material and the film. paper container. The heat sealing agent applied to at least one of the paper base material and the film is dispersed in a dispersed manner that allows the film to be peeled from the paper base material, and is dispersed in dotted, linear, or lattice-like shapes. 5. The paper container according to claim 4, wherein the paper container is coated with at least one pattern. 4. The heat sealing agent applied to at least one of the paper base material and the film is applied at a concentration that allows the film to be peeled from the paper base material. The paper container described in .

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