JP6025323B2 - Composite paper container - Google Patents

Description

  The present invention relates to the field of paper containers. Specifically, a strip-shaped plastic member is provided at the opening of the paper container.

  Paper containers are used in various fields. In particular, in order to maintain hermeticity, a container having a circular opening is often used. When the opening is circular, the entire opening can be uniformly heat-sealed evenly when the lid member is heat-sealed from above with a polyethylene or the like. For this reason, it is easy to avoid problems such as leakage of contents due to seal leakage.

  On the other hand, if the opening has a polygonal shape, even if the edge including the edge extending from the opening is sealed, the opening with the lid 3 is formed at the polygonal corner of the paper container 1 as shown in FIG. The heat seal of the part becomes a contact state at a point.

  In such a case, the heat seal at the corner is often not sufficient. For this reason, there is a possibility that problems such as leakage of contents from the corners may occur.

  On the other hand, as a general technique, a method of attaching a plastic opening edge member having rigidity as disclosed in Patent Documents 1 and 2 is disclosed as a method for solving the disadvantages of the paper container. .

JP 2009-286404 A JP2011-207507

However, all of the above prior arts are based on the use of rigid plastic. Moreover, the opening is not intended for a polygonal paper container. Therefore, these prior arts do not solve the problem in the case where the lid member is heat-sealed at the corners of the opening as described above.

Therefore, the present inventors have aimed to develop a paper container in which the lid can be reliably heat-sealed from above in a paper container having a polygonal opening.

  As a result of the diligent research by the present inventors, in a paper container having an opening having a polygonal shape, a plastic member having a belt-like flexibility having a predetermined width formed by covering the opening along the opening is welded. And found that the covering method is effective.

  It has been found that by providing such a plastic member in advance, it is possible to obtain a structure that does not leak at the corners of the opening when the lid is further heat sealed from above as described above.

  In order to prevent leakage or the like in the side surface of the container, as a base material of the paper container, a plastic film layer is laminated on at least one surface of the base paper by extrusion or bonding, and the laminated surfaces are welded together. Or the sealing of a side part can be ensured by heat-sealing.

That is, the first invention of the present application is
“A paper container formed from a paper base material having a plastic film layer laminated on at least one side of a base paper, and having an opening having a polygonal shape and an edge continuous with the opening;
A plastic member having a strip-like flexibility having a predetermined width is formed so as to cover the opening along the opening,
The paper container has a sealed side surface,
A composite paper container in which the belt-shaped plastic member is welded so as to cover the inner surface and the edge of the container side surface at the periphery of the opening. "
.

Moreover, it is preferable that the film layer laminated on the base paper and the strip-shaped plastic member are the same.
That is, the second invention of the present application is
“The composite paper container according to claim 1, wherein the film layer laminated on the base paper and the belt-shaped plastic member are made of the same plastic material.”
.

In addition, in order to ensure the heat sealability of the lid member at the corner of the opening, the predetermined portion of the plastic member having the flexibility projects so as to protrude into the space between the adjacent edges at the corner. It is desirable to be located.
That is, the third invention of the present application is
“The composite paper container according to claim 1 or 2, wherein a predetermined portion of the strip-shaped plastic member is located at a corner of the polygonal shape so as to protrude into a space between adjacent edges.”
.

Moreover, about the said edge part, after heat-sealing a cover material, it is suitable when it is set as an outer cover by obstruct | occluding.
That is, the fourth invention of the present application is
“The composite paper container according to claim 1, wherein the container opening is closed by folding the edge.”
.

Furthermore, in the present invention, when the side surface portion of the paper container has a tapered shape, the contents can be easily taken out from the opening portion.
That is, the fifth invention of the present application is
“The composite paper container according to claim 1, wherein a side surface of the paper container has a tapered shape.”
.

Next, the present application also contemplates a form of a product or the like in which the composite paper container is filled with predetermined contents and then heat-sealed with a plastic film or the like as a cover material.
That is, the sixth invention of the present application is
"The composite paper container according to any one of claims 1 to 5, wherein the opening is heat-sealed with a plastic film after filling the predetermined contents."
.

The composite paper container according to the present invention can reliably heat-seal the plastic lid member while making the opening polygonal, thereby preventing leakage of contents. Moreover, even when foods with high hygroscopicity are stored by selecting a film material, long-term storage is possible.

It is a perspective view of the composite paper container in the embodiment of the present invention. It is a schematic diagram of the manufacturing process of the composite paper container in the embodiment of the present invention. It is the expanded view (a) of the paper container in embodiment of this invention, and the perspective view (b) in the middle of an assembly. It is a schematic diagram which shows the welding relationship of the folding part 12 and the side part 13 of the paper-made containers in embodiment of this invention. It is a perspective view of the state which engaged the edges in the embodiment of the present invention. The example (a)-(d) of the plastic member 12 in embodiment of this invention is shown. It is a perspective view schematic diagram until it engages with a cover part after heat-sealing the cover material 3 in embodiment of this invention. It is the perspective view made into the structure which exposes the hot water cutting hole by carrying out the half cut process of the said cover material as a cover material of the multiple layers in embodiment of this invention. It is the perspective view which enabled it to remove a part of cover material in embodiment of this invention circularly. It is an expanded view of the paper container in embodiment of this invention. It is a perspective view of the composite paper container in the embodiment of the present invention. It is the reference figure which showed the state which heat-sealed the container whose opening part is a polygonal shape by the method until now.

DESCRIPTION OF SYMBOLS 1 Paper container of 1st embodiment 11 Bottom part 12 Folding part 13 Side surface part 14 Edge part 2 Plastic member 21 Corner | angular part 22 L-shaped part 3 Cover material 31 Hole 32 Extraction hole 4 Paper container of 2nd embodiment 43 Side 44 Edge

Embodiments of the present invention will be described below with reference to the drawings. The present invention is not limited to these embodiments.

─Overall explanation─

FIG. 1 is a perspective view of a composite paper container according to a first embodiment of the present invention.
The composite paper container of the present invention is completed by welding a belt-shaped plastic member 2 to a paper container 1 as shown in FIG.

─Paper container─

In the first embodiment of the present invention, a taper type having a developed view as shown in FIG. 3A is used as a paper container. That is, a sheet of paper sheet material is folded, and the folded portion 12 at the corner as shown in FIG. The type that is bonded is used.

Here, as the paper sheet material, a paper base material in which polyethylene terephthalate (PE) is extruded and laminated as a single layer on both sides of the base paper is used.
The paper substrate used in the present invention is only required to have a plastic film layer laminated on at least one side of the base paper. Various plastics can be used. Specific examples include polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and ethylene / vinyl acetate copolymer resin (EVA).

  Moreover, the plastics of these film layers may not be a single composition but may be a mixture thereof. Furthermore, these film layers are not limited to a single layer, but may be a multilayer such as “paper // PET / PE”.

  The method for laminating these plastic films is not particularly limited, and any method of extrusion lamination and dry lamination can be used. A known method can be used for these laminates. Further, in order to improve the laminating property of the base paper, it is preferable to treat the paper surface with an ozone treatment or the like.

  For polyethylene terephthalate (PET), the heat-sealable laminate described in Japanese Patent No. 4750909 is effective. When bonding the plastic film surfaces to be laminated, there is also a method of bonding using an adhesive, but welding is performed by heating, ultrasonic waves, high frequency processing, etc. while both surfaces are in contact with each other. It is preferable that both surfaces can be bonded together.

  The term “welding” as used in the present invention refers to a state in which the surfaces are completely sealed and difficult to remove, and the substrate is destroyed if it is forcibly removed. Specifically, in addition to the case where the heating time of the heat seal is lengthened, the one processed by ultrasonic waves / high frequency is included.

In the first embodiment, the surface laminated with polyethylene is used as the inner surface (A surface) of the container as shown in FIG. 3) X) can be welded. As a result, a sealed state with respect to the outside of the side surface of the container can be ensured as will be described later.

  In addition, these laminations are preferably performed on both sides of the base paper. When using a type that assembles a container from a single blank sheet as shown in this embodiment, by laminating on both sides, the contact surface between the outer surfaces of the containers (Y in FIG. 4) is also used for welding without using an adhesive. It is because it can adhere | attach by doing.

Specifically, as shown in FIG. 4, in the first embodiment, the plastic laminated surface is also laminated on the surface (B surface) opposite to the inner surface (A surface) of the container. As a result, the folded portions 12 at the four corners can be welded to the side wall portion 13.

--The opening must be polygonal--

In the present invention, the opening of the paper container 1 has a polygonal shape. In 1st embodiment of this invention, the opening part has disclosed the square type. The polygonal opening is generally a quadrangle as shown in FIGS. 1 and 2. The quadrangular shape includes various forms such as a square and a rectangle. Of course, it may be a pentagon or a hexagonal polygon.

─ Edge ─

In this invention, as shown in this 1st embodiment, it has the edge part 14 following this opening part. Although this edge is continuous with the opening, it may be continuous from a single sheet of paper, or may be added by bonding or the like after the paper container 1 is assembled.

In addition, as shown in FIG. 5, it is preferable that the edge part 14 can be bend | folded and the opening part can be obstruct | occluded after the heat sealing etc. of the cover material 3 mentioned later. By doing in this way, a part or all of edge 14 can be used as an outer lid. As a result, resistance to external impacts and the like can be obtained. Moreover, the outer lid | cover can be closed by making the edge vicinity vicinity of an edge part engageable with the edge parts which face each other.

─Sealing of side surface─

  In the paper container 1 of the present invention, the side surface portion 13 needs to be sealed. The object of the present invention is to maintain the airtightness of the entire container. For this reason, it is necessary to ensure the airtightness of the side surface portion 13 as well.

  In the first embodiment, the polyethylenes on the inner surfaces of the folded portions 12 at the four corners in FIG. 3 are bonded together by heating and welding. For this reason, there is no direct contact with the outside air from the folded portion, and the sealing property is ensured.

In addition, in the case of the folding part 12 like this embodiment, the whole inner surface of the folding part 12 does not need to adhere | attach, and a part of adhesion | attachment may be sufficient. However, in this case, the airtightness of the entire side surface portion needs to be ensured by a combination with the welding of the band-shaped plastic member 2 described later.

--Striped plastic material--

  In the present invention, a plastic member 2 having a strip-like flexibility is provided for the paper container 1. In the first embodiment, as shown in FIGS. 1 and 2, a strip-shaped plastic member 2 is welded to the periphery of the opening of the paper container 1.

  By providing the plastic member in this way, when the plastic film lid member 3 described later is heat-sealed, it can be heat-sealed not only at the corners of the opening but also between the surfaces. As a result, leakage at the corners of the opening can be prevented and sealing performance can be improved.

  These plastic members 2 are prepared according to the shape of the opening. The plastic member 2 can be appropriately prepared by a known method. After arranging this at a predetermined position in the opening of the paper container 1, it is welded and bonded to the paper container 1 by heating, ultrasonic treatment or high frequency treatment.

  In the first embodiment, a plastic member 2 as shown in FIG. 6 (a) is prepared, and this is disposed in the opening of the paper container 1, and is welded by ultrasonic waves to form a belt-like plastic member. 2 is glued. In the present embodiment, the corner portion 21 of the plastic member 2 is cut into a so-called webbed shape. However, the present invention is not limited to this, and it is needless to say that the portion shown in FIG.

  Furthermore, in the first embodiment, the central portion of the belt portion is formed so that the cross-section becomes the L-shaped portion 22 from the outside from the viewpoint of enhancing the sealing performance by welding to the paper container 1 that is the main body portion. Shows what it is. In the present invention, the band shape includes such an L-shaped cross section.

However, the present invention is not limited to this configuration. For example, as shown in FIG. 6C, the L-shaped portion 22 may be provided only in the corner portion 21. Furthermore, the plastic member 12 shown in FIG. 6 (d) that does not have such an L-shaped portion is also possible. In this case, it can be welded to the periphery of the opening while forming an L shape by the stress caused by heating and pressing. In addition, FIG. 6 shows only the closed plastic member, but the present invention is not limited to this and may be an open type.

─ Have flexibility ─

  The strip-shaped plastic member 2 needs to have flexibility. In the present invention, as shown in FIG. 1, the predetermined portion of the strip-shaped plastic member 2 is positioned so as to protrude into a space between adjacent edges at the polygonal corners. Since it is such a structure, after the heat sealing of the lid | cover material 3 after that, the edge part 15 needs to be bent and bent. For this reason, the plastic member needs flexibility.

Various methods are conceivable for providing flexibility, but first, it is possible by appropriately selecting a plastic material. Moreover, when giving flexibility, the thickness also becomes a problem. Although depending on the type of plastic material, generally, the thickness of the member needs to be approximately 200 μm or less. However, generally 12 to 70 μm is common.

─Material of plastic parts─

  Various materials can be used as the plastic member 12. Specific examples include polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and ethylene / vinyl acetate copolymer resin (EVA). Moreover, these plastic materials may not be a single composition but may be a mixture of these resins. Of course, not only these single layers but also multiple layers may be used.

  In addition, about polyethylene terephthalate (PET), PET itself laminated | stacked on the heat-sealable laminated body described in Japanese Patent No. 4750909 can be utilized.

The material of the plastic member 12 is preferably matched with the material of the outermost layer of the plastic layer laminated on the base paper of the paper container 1 described above. For adhesion of the plastic member 12 to the paper container 1, heating, high frequency or ultrasonic waves can be used. In this case, welding is easier when the material is homogeneous.

—Plastic material coverage—

As shown in FIG. 1 and FIG. 2, the range in which the belt-shaped plastic member 12 covers the paper container 1 covers not only the opening but also the inner surface and the edge 14 of the container side surface 13 around the periphery of the opening. . By covering up to the inner surface of the container side surface portion 13, the sealing performance can be secured safely.

─ Projection to adjacent space ─

In the present invention, as shown in FIG. 1 and FIG. 2, the predetermined portion of the strip-shaped plastic member 2 is positioned so as to protrude into the space between adjacent edges at the polygonal corners. Thus, by having an overhang | projection part, it can heat-seal with a cover material in the said overhang | projection part so that it may mention later. For this reason, the leak etc. in the corner | angular part of a container opening part can be prevented favorably. Although there is no restriction | limiting about the extent of an overhang | projection, What is necessary is just the range which can heat-seal with the cover material 3 favorably.

─Heat sealing of the cover material to the opening after welding plastic parts─

  The composite paper container manufactured by the above-described process is heat-sealed with the lid 3 after the necessary objects are stored. Various materials can be selected as the material of the lid member 3 to be heat sealed. That is, various plastic materials and mixed materials thereof can be selected. These can be selected as appropriate.

  Moreover, the plastic material of the same system as the material of the outermost layer of the said strip | belt-shaped plastic member 2 is preferable from a heat sealable viewpoint. That is, in the first embodiment, when the material of the outermost layer of the plastic member to be welded is polyethylene (PE), the heat sealing surface of the lid member 3 to be heat-sealed from the top may have PE. preferable.

Needless to say, the cover 3 may include a plastic material on the heat seal surface and a layer of aluminum or paper. Moreover, after heat-sealing this lid | cover material 3, it shows in FIG. 8 about the outline after folding an edge part to make an outer lid | cover.

─ How to use this container ─

  This container can be used for various foods that are problematic when moisture is absorbed. For example, it can be used for highly hygroscopic materials such as sugar and salt. Further, it is possible to store liquid substances by increasing the sealing degree.

  Further, as shown in FIG. 8, the lid member 3 may be configured such that the lid member 3 is subjected to half-cut processing as a multi-layer lid member 3 to expose the hot water cut-out hole 31. Since this composite paper container has a sealed property, it can also be used as a container for instant foods such as fried noodles that are reconstituted in hot water.

Furthermore, as shown in FIG. 9, a method of removing a part of the lid member 3 so that the take-out hole 32 can be provided is also possible. In this way, contents such as powder such as sugar can be enclosed inside, and if necessary, a necessary amount can be taken out from the hole with a spoon or the like. Furthermore, when the composite paper container of the present invention is used as it is for the purpose of long-term storage after the lid material 3 is opened, a cover lid or the like can be separately prepared.

─Other forms of paper containers─

  In the first embodiment described above, a type is shown in which the center of one paper substrate is the bottom surface, and the four corner folds are provided and assembled, but the present invention is not limited to this type. Absent. For example, the container 4 having a substantially rectangular parallelepiped shape as shown in FIG.

  Such a rectangular parallelepiped type may be a type having a bottom. Moreover, the case where there is no bottom part may be sufficient as shown in FIG.

  In the type having no bottom as shown in FIG. 10, a method of providing the above-described plastic member 2 in the bottom opening is possible. In this case, on the side of the opening, it is preferable that the lid member 3 is welded to make it difficult to peel off.

  Thus, the paper container that can be used in the present invention is not limited to a specific shape, and various forms are possible.

Claims (6)

A paper container formed from a paper base material laminated with a plastic film layer on at least one side of a base paper, and having an opening having a polygonal shape, continuous to the opening, and having a foldable edge;
A plastic member having a strip-like flexibility having a predetermined width is formed so as to cover the opening along the opening,
The paper container has a sealed side surface,
The band-shaped plastic member is welded so as to cover the inner surface and edge of the container side surface at the periphery of the opening,
A composite paper container in which a predetermined portion of the strip-shaped plastic member is positioned in a space between adjacent edges at a polygonal corner of the opening.   2. The composite paper container according to claim 1, wherein the film layer laminated on the base paper and the belt-shaped plastic member are made of the same plastic material. Composite paper container according to the container opening in one of the closable claim 1 or 2 by folding the edges.   The composite paper container according to any one of claims 1 to 3, wherein a side surface portion of the paper container has a tapered shape. The composite paper container according to any one of claims 1 to 4, wherein the opening can be heat-sealed with a plastic film after filling the predetermined contents.   The composite paper container according to any one of claims 1 to 5, wherein the protruding portion is cut into a web shape.