JP2007217019A - Easily openable container, container body, manufacturing method of easily openable container and manufacturing apparatus for easily openable container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an easily openable container provided with sealability and openability by easily and precisely forming a part for starting or finishing delamination of a flange part. <P>SOLUTION: In forming this easily openable container 1, a cover material 3 and the flange part 25 of a container body 2 made of a multi-layer sheet containing a surface separation layer 21 and a base material layer 20 are melted at a melt seal part 26. The surface separation layer 21 of a protrusion 28 provided in advance and at a position different from the seal part 26 of the flange part 25 is partially removed or reduced in thickness. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an easily openable container, a container body, a method for manufacturing an easily openable container, and an apparatus for manufacturing an easily openable container.

As a packaging form for foods, after the foods are stored inside the container, the container body is provided with a flange body provided with a flange on the periphery of the opening of the container body, and a film-shaped lid member. Containers with lids that are hermetically sealed by heat sealing the lid material are widely used.
Such a container with a lid is a seal formed by heat-sealing the flange portion provided on the container body and the lid material from the viewpoint of safely storing food stored in the container. When the lid is opened, the lid is easily peelable from the container body, and there is a contradiction between hermeticity and easy opening. It was necessary to have the characteristics at the same time.

  In a container with a lid (easy-opening container) having such characteristics, it is a fatal problem for the contents to leak, so even if the easy-opening is somewhat sacrificed, The sealing conditions (sealing temperature, sealing pressure) were set high to make the seal part difficult to peel off, so that the contents did not leak to the outside of the container. As a result, the container did not have easy-openability. There was a problem such as.

Against this background, various techniques have been studied for obtaining an easy-open container having both high sealing performance and easy opening. For example, opening is performed by peeling between the seal layer of the container body and its adjacent layer, and a notch for starting or ending delamination is provided in the flange portion of the container body so that the seal layer is excellent from the container body. A technique for breaking is provided.
For example, in Patent Document 1, a container main body is formed from a plurality of layers that can be peeled from each other, and a cut is formed on the opening side of the flange portion of the container main body along the periphery of the opening. The structure which heat-sealed the flange part and the lid | cover material is shown. When the lid member is pulled with respect to the flange portion in order to peel off the lid member, delamination is started from the outer peripheral edge of the flange portion, and this delamination ends at a position where there is a cut. Since the interlayer adhesive force of the flange portion is smaller than the adhesive force between the flange portion and the lid member, the lid member is easily peeled off.

Here, examples of means for forming the incision include mechanical means such as a cutting blade and a cutting blade, and means by heating such as hot wire fusing and fusing with a hot blade. By cutting the cutting blade and the flange portion relative to each other while the cutting blade is in contact with the flange portion, a cut along the opening is formed in the flange portion.
2. Description of the Related Art Conventionally, a flange body is provided on the periphery of an opening, and a container body formed of a multilayer sheet and a lid member melt-sealed at the flange part of the container body are provided, and face the lid member of the flange section. There exists an easily openable container which formed the cyclic | annular convex part on the layer so that it might protrude (patent document 2). In Patent Document 2, the lid member and the flange portion are strongly sealed by the convex portion.

Japanese Patent Publication No. 5-75637 JP 2000-31380 A

In Patent Document 1, a notch is formed to terminate delamination at the flange portion of the container body. However, in the notch forming means, a means for making an incision with respect to the flange portion of the container body with a cutting blade, a cutting blade, and a hot blade. Therefore, it is difficult to control the depth of cut, and it is difficult to adjust the cut formation position along the surface direction of the flange portion.
For example, in the case of a container body with a thin flange portion, there is a problem that the flange portion itself is cut if the accuracy of the cutting depth is poor, and further, if the flange portion includes an oxygen gas barrier layer, If this oxygen gas barrier layer is cut, a problem is caused in the easily openable container.
Further, in the case where an oxygen absorbing layer is provided between the oxygen gas barrier layer and the surface peeling layer, when the cut reaches the oxygen absorbing layer even if the oxygen gas barrier layer is not cut, the cut contacts the contents. There are also hygiene problems.
For this reason, conventionally, it is necessary to increase the accuracy of the cutting depth, and for this reason, skill of the operator and complicated control of the apparatus are required.

Further, when the notch is formed in the flange portion of the container body, the container body may be deformed although the container body is fixed by the bucket. As a result, the positional accuracy in the direction parallel to the plane of the flange portion of the notch to be formed is not sufficient, and there is a limit to application to a narrow flange.
In patent document 2, a convex part is provided in order to seal strongly with a cover material, and is not for peeling a cover material from a container main body simply. Therefore, the problem shown in Patent Document 1 cannot be solved simply by forming a convex portion on the flange portion.

  An object of the present invention is to easily and accurately form a portion for starting or ending delamination at a flange portion, and thus an easily openable container, a container body, and an easily openable container having both high sealing performance and easy opening performance. It is providing the manufacturing method of this, and the manufacturing apparatus of an easily openable container.

  An easily openable container of the present invention comprises a container body formed of a multilayer sheet with a flange portion disposed at the periphery of the opening, and a lid member melt-sealed by the flange portion of the container body. The sheet has a surface peeling layer to be bonded to the lid member and a base material layer to be bonded to the surface peeling layer, and an adhesive force between the surface peeling layer and the base material layer of the container body is the surface. An easy-open container formed smaller than the adhesive strength of the melt seal portion between the release layer and the lid material, and a protrusion provided in advance in a position different from the melt seal portion in the surface release layer of the flange portion The surface peeling layer of the part is removed or thinned.

In the easily openable container of the present invention, when the lid member is peeled off from the flange portion of the container body, the flange portion starts delamination from the removed portion or the thinned portion of the flange portion, or, finish. In this invention, since the interlayer adhesive force of the surface peeling layer and base material layer of a container main body is formed smaller than the adhesive force of a surface peeling layer and a cover material, the interlayer peeling of a flange part advances smoothly.
Here, in the present invention, the removal of the surface peeling layer of the flange portion refers to a state in which a part of the layer adjacent to the surface peeling layer is exposed and can be in direct contact with the lid material. What is thinning of the surface peeling layer? It means that a part of the surface peeling layer is broken without applying a large force when the lid member is peeled off from the flange portion.

In the present invention having the above configuration, in order to form the start position or the end position of the delamination of the flange portion, in the surface peeling layer of the flange portion, for example, a protrusion provided in advance at a position different from the melt seal portion, It is removed using a heating plate that melts with heat or other means.
For this reason, if a device having a planar processed part such as a heating plate is used to remove or thin the surface peeling layer of the protrusion provided on the flange part, it is formed on the processed part and the flange part of this device. Even if the relative arrangement position with respect to the protruding portion is slightly deviated, removal of the surface peeling or thinning can be performed with high accuracy. Therefore, in the present invention, it is possible to easily and accurately form the start part or the end part of the delamination of the flange portion, and to improve both the sealing property and the easy opening property of the easily openable container. it can.

Here, in this invention, the structure by which the said projection part is provided in the said opening part side rather than the said fusion seal part is preferable.
In the invention of this configuration, it is possible to accurately and easily form the portion where the delamination of the flange portion ends.

In this invention, it is preferable that the said protrusion part is provided in the flange outer edge side opposite to the said opening part side from the said fusion | melting seal part.
In the invention of this configuration, the portion where the delamination of the flange portion is started can be accurately and easily formed.

The base material layer preferably includes an adhesive layer that can be repeatedly peeled off and adhered to the surface release layer.
In the invention of this configuration, when the lid material once peeled off is attached to the container body again, the surface peeling layer integrated with the lid material and the adhesive layer integrated with the container body are polymerized. Therefore, the lid member and the flange portion are bonded together with a predetermined adhesive force. Therefore, the lid member can be repeatedly attached to and detached from the container body.
Furthermore, the base material layer preferably includes an oxygen-absorbing resin layer.
In the invention with this configuration, since the oxygen-absorbing resin layer is provided on the base material layer, an easily openable container having a high gas barrier property can be provided. In addition, since the oxygen-absorbing resin layer is not exposed, an easily openable container that is hygienic and has high pressure resistance is obtained.

The container main body of the present invention is a container main body in which a flange portion is disposed on the periphery of the opening, and is formed of a multilayer sheet, and can be melt-sealed with a lid material at the flange portion, and the multilayer sheet is the lid material A surface peeling layer to be bonded to the surface peeling layer and a base material layer to be bonded to the surface peeling layer, and an adhesive force between the surface peeling layer and the base material layer of the container body is the surface peeling layer and the lid. The surface peeling layer of the protruding portion provided in advance in a position different from the melt seal portion in the surface peeling layer of the flange portion is removed or thinned. .
In the invention of this configuration, it is possible to provide a container body that exhibits the same effects as the above-described easy-open container.

The method for manufacturing an easily openable container according to the present invention is a method for manufacturing an easily openable container having the above-described configuration, in which a mold having a protrusion is disposed on the opposite side of the lid of the flange portion, The flange is thermoformed with a mold to form the protrusion, the surface peeling layer of the protrusion is removed or thinned, and then a lid is melt-sealed to the flange.
In the invention of this configuration, in order to form the protrusion of the container body, a mold is disposed on the flange, and the mold is heated to form the protrusion on the flange along the shape of the protrusion of the mold. . Then, after removing or thinning the surface peeling layer of the protruding portion by an appropriate means, the lid member is melt-sealed to the flange portion using a seal bar or the like.
In the present invention, a mold is used to form the protrusion on the container body. By using a mold, it is possible to form protrusions having the same shape on the flange, so that a number of easily openable containers having the same shape can be manufactured.

In the manufacturing method of the easily openable container of this invention, the structure which presses a heating plate to the said projection part in order to remove the said surface peeling layer in the said projection part or to make it thin is preferable.
In the invention of this configuration, in order to remove or thin the surface peeling layer, the heating plate is moved toward the protruding portion, and the protruding portion is pressed with the heating plate. The heating plate can easily remove or thin the surface peeling layer by controlling the heating temperature and the pressing time to the protrusion. Since the heating plate is a flat portion having a predetermined area in contact with the protruding portion, even if the heating plate is slightly misaligned with the protruding portion, removal or thinning of the surface peeling layer is inconvenient. Can be implemented without.

An easily openable container manufacturing apparatus according to the present invention is an apparatus for manufacturing an easily openable container having the above-described configuration, and is a mold having a protrusion disposed on the side of the flange portion opposite to the lid member, and the protrusion A heating plate that can be brought into contact with the portion and removes or thins the surface peeling layer of the flange portion; and a seal member that melts and seals a lid material on the flange portion.
In the invention of this configuration, the above-described method for producing an easily openable container can be realized by simple means.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, a first embodiment of the present invention will be described with reference to FIGS.
[First Embodiment]
(I) Configuration of the easy-open container 1:
FIG. 1 is a schematic view showing an easy-open container 1 according to a first embodiment of the present invention, FIG. 1 (A) is a state sealed with a lid member 3, and FIG. 1 (B) is an opening start portion. The state which opened the cover material 3 from 4 is shown, respectively. FIG. 2 is a cross-sectional view of the main part of FIG.

The easy-open container 1 includes a container body 2 having a flat rectangular shape. The container body 2 is placed on the periphery of the opening 24 of the container body 2 with the lid 3 placed on the opening 24. The sealed flange portion 25 and the lid member 3 are heat-sealed to form an annular melt-sealed portion 26, and as shown in FIG. 1 (A), the inside of the easy-open container is sealed.
The melt seal portion 26 is formed from the middle position of the flange portion 25 to the outer peripheral edge portion, and the seal member 7 is used for the formation (see the imaginary line in FIG. 2).
A bucket (not shown) is arranged at a position facing the flange portion 25 of the seal member 7, and the seal member 7 is pressed from the top of the lid 3 to the flange portion 25 in a state where the flange portion 25 is supported by the bucket. .

(I-1) Configuration of container body 2:
The container main body 2 shown in FIGS. 1 and 2 is formed from a multilayer sheet composed of three layers of a surface peeling layer 21, an adhesive layer 22 and a lower layer 23. In this embodiment, the container body 2 is formed from the adhesive layer 22 and the lower layer 23. 20 is configured.
The container body 2 has a substantially rectangular tray shape having a predetermined depth, and has a substantially rectangular opening 24, and a flange portion 25 is formed on the periphery of the opening 24 so as to project outward. It is arranged. In addition, the code | symbol 27 shown by FIG. 1 is a spout formed in the opening start part 4 of the flange part 25 in order to assist opening.

The resin that can form the surface release layer 21 is preferably a material having a heat seal property. For example, a polyolefin resin such as polypropylene (PP) resin or polyethylene (PE) resin, or amorphous polyethylene terephthalate is used. It is preferable to use it. The thickness of the surface peeling layer 21 is preferably 10 μm to 200 μm, but varies depending on the size and use of the container.
The adhesive layer 22 constituting the base material layer is formed of a material that can be repeatedly peeled off and adhered to the surface release layer 21, and the material is, for example, an ethylene-vinyl acetate copolymer, and its thickness is The size varies depending on the size and use of the container. In the present embodiment, the adhesive layer 22 may be omitted, and the base material layer 20 may be configured only from the lower layer 23.
Here, the adhesive force between the surface release layer 21 and the adhesive layer 22 constituting the base material layer is formed to be smaller than the adhesive force of the fusion seal portion between the surface release layer 21 and the lid member 3.

  The lower layer 23 that constitutes the base material layer 20 is a layer that appears outside the container body 2, and examples of the constituent material include olefin resins such as polypropylene resin and polyethylene resin, polystyrene resins, polyethylene terephthalate (PET), and the like. Materials such as polyester resins, and single layer sheets or laminated sheets of these blend materials, and in order to give gas barrier properties, for example, ethylene vinyl alcohol copolymer, nylon, polyethylene terephthalate (PET), polyvinylidene chloride A resin material such as (PVDC) or a resin that forms a gas barrier layer formed by aluminum vapor deposition or the like can be used.

For example, in this embodiment, the layer structure of the container body 2 can be as follows. For example, (1) a laminated sheet comprising a surface release layer of high density polyethylene (HDPE) having a thickness of 20 μm to 150 μm and a polypropylene layer having a thickness of 100 μm to 2500 μm, and (2) a surface release layer of polypropylene having a thickness of 20 μm to 150 μm. And a laminated sheet comprising a polypropylene and polyethylene layer having a thickness of 50 μm to 500 μm and a polypropylene layer having a thickness of 100 μm to 2500 μm, (3) a surface release layer of polypropylene having a thickness of 20 μm to 150 μm, a polypropylene having a thickness of 50 μm to 500 μm, and A laminated sheet comprising a polyethylene layer, an oxygen-absorbing resin layer having a thickness of 50 μm to 500 μm, and a total of 320 μm to 2500 μm of polypropylene, an adhesive layer, an ethylene vinyl alcohol copolymer layer, and a polymer layer of a polypropylene layer, (4) thickness 20 μm to 150 μm PET surface release layer Sheet having a thickness of 20 μm to 200 μm, an oxygen absorbing resin layer having a thickness of 50 μm to 500 μm, and a total of 320 μm to 2500 μm of polypropylene, an adhesive layer, an ethylene vinyl alcohol copolymer layer, and a polypropylene polymer layer. (5) A laminated sheet composed of a polypropylene surface release layer having a thickness of 20 μm to 150 μm, an adhesive layer having a thickness of 5 μm to 100 μm, and a lower layer of polypropylene having a thickness of 100 μm to 2500 μm can be exemplified. For the adhesive layer, maleic anhydride-modified PP and other materials can be used.
These laminated sheets can be produced by coextrusion, thermal lamination, dry lamination, or the like, and can also be carried out by combining these steps.

(I-2) Configuration of the lid member 3:
In this embodiment, the lid 3 is a laminated body including an outer layer 32 that appears outside the easy-open container 1, a surface peeling layer 21 of the container body 2, and a seal layer 31 that is heat-sealed.
For the sealing layer 31, for example, LDPE (low density polyethylene) including L-LDPE, polypropylene, and other materials can be used.
As the outer layer 32 constituting the lid member 3, a polyethylene terephthalate (PET) film, a biaxially stretched nylon film (O-Ny), or the like can be used.

(I-3) Formation of protrusions:
In the easy-open container 1 of this embodiment, as shown in FIG. 2, the protrusion part 28 is formed over the perimeter along the opening 24 of the flange part 25, or a part of the perimeter is excluded. The protrusion 28 is formed at a predetermined distance from the melt seal portion 26 toward the opening 24.
The protrusion 28 has a curved shape such that a part of the surface peeling layer 21, the adhesive layer 22, and the lower layer 23 protrudes toward the lid member 3, of which the top of the surface peeling layer 21 is removed and the adhesive layer 22 is removed. This is a structure in which a part of is in direct contact with the lid 3. The portion from which the surface peeling layer 21 is removed and the lid member 3 are not sealed or have a low strength even if sealed. Therefore, even if pressure is applied to the inside of the container due to an increase in the outside air temperature or the like, the pressure is concentrated not on the portion where the surface peeling layer 21 is removed but on the inner peripheral edge of the melt seal portion 26, and the lid material is mistakenly formed. 3 is not peeled off from the flange portion 25. In this embodiment, in addition to the removal of the surface peeling layer 21, the surface peeling layer 21 can be partially broken without applying a large force when the lid 3 is peeled off from the flange portion 25. It may be thinned.
The projecting portion 28 may have a cross-sectional shape that may be rectangular, triangular, or semicircular.
In the present embodiment, if the lid member 3 is pulled upward (in the direction of the arrow in FIG. 1B), the delamination of the flange portion 25 starts from the position of the outer peripheral edge P1 between the surface peeling layer 21 and the adhesive layer 22. It starts and ends at a portion P2 where the top of the surface peeling layer 21 of the protrusion 28 is removed.

FIG.3 and FIG.4 is a schematic block diagram which shows a part of manufacturing apparatus of an easily openable container, respectively.
In FIG. 3, the easy-open container manufacturing apparatus includes a protruding portion forming apparatus 100 that forms a protruding portion 28 on the flange portion 25 of the container body 2.
The protruding portion forming apparatus 100 includes a mold 102 disposed on the opposite side of the flange portion 25 from the lid member 3, a flange presser 103 disposed on the opposite side of the flange portion 25 of the mold 102, and a container And a plug 104 that forms an opening 24 for storing the contents of the main body 2.
The mold 102 has a recess 102B for forming the opening 24 of the container body 2 in the center, and the upper end edge of the recess 102B has a rectangular cross section for forming the protrusion 28 on the flange 25. The protrusion 102A is formed. The multilayer sheet 20A constituting the container body 2 is fed between the mold 102, the flange retainer 103, and the plug 104, and in this state, the flange retainer 103 and the plug 104 are moved to the mold 102 to store the contents. The concave portion, the flange portion 25, and the projection portion 28 are formed on the multilayer sheet 20A at a time. In the present embodiment, the protrusion 28 along the shape of the protrusion 102 </ b> A is formed on the flange portion 25 by performing thermoforming such as plug assist vacuum forming and plug assist pressure forming as described above. In the present embodiment, the plug body 104 and the flange presser 103 may be omitted, and the container body 2 may be formed by vacuum forming, pressure forming, or the like.

In FIG. 4, the easy-open container manufacturing apparatus includes a protrusion removing device 101 that removes the protrusion 28 formed by the protrusion forming apparatus 100, and further includes a seal member 7 and a bucket ( (Not shown).
The protrusion removing device 101 includes a bucket 105 that holds the container body 2, and a heating plate 106 that can come into contact with the top of the protrusion 28 of the container body 2 held by the bucket 105. The bucket 105 holds the container body 2 molded by the protrusion forming apparatus 100 and sufficiently cooled after a predetermined time. Further, the upper end surface of the bucket 105 is flat, and no protrusion formed on the mold 102 is formed.
The heating plate 106 is for removing or thinning the surface peeling layer 21. When the heating plate 106 is pressed against the top of the protrusion 28 while being heated at a predetermined temperature, the pressing portion is heated and the surface peeling layer is heated. A part of 21 is melted to expose the adhesive layer 22. The heating plate 106 is controlled by a control device (not shown) with respect to the heating temperature and the pressing time to the protrusion 28.
The heating plate 106 has a processed surface having a width that is larger than the width of the protrusion 28, and can be moved close to and away from the protrusion 28.
The heating plate 106 is formed in a substantially disc shape so as to follow the shape of the flange portion 25.
In the present embodiment, the multilayer body 20A on which the container body 2 is formed by the protrusion forming device 100 and the protrusion removing device 101 is punched out with a press or the like to complete the forming of the container body 2. The protrusion 28 may be formed and the surface peeling layer 21 may be removed before, and the protrusion 28 and the surface peeling layer 21 may be removed after the punching process.
When the surface peeling layer 21 of the protrusion 28 is removed or thinned, the lid 3 is overlapped on the flange 25 of the container body 2 and both are melt-sealed via the seal member 7.

(I-4) Effects of this embodiment:
According to the first embodiment, the following effects can be achieved.
(1) The easy-open container 1 in which the flange part 25 and the lid member 3 of the container body 2 formed from a multilayer sheet including the surface peeling layer 21 and the base material layer 20 are melted by the melt seal part 26, A part of the surface peeling layer 21 of the protruding portion 28 provided in advance at a position different from the melt seal portion 26 of the flange portion 25 is removed or thinned. Therefore, the position where the delamination of the flange portion 25 required when the lid member 3 is peeled off from the flange portion 25 can be accurately formed. That is, in order to remove or thin the surface peeling layer 21 of the protrusion 28 provided on the flange portion 25, the surface is not cut perpendicular to the plane of the surface peeling layer 21 as in the case of forming a cut. By processing the surface peeling layer 21 of the protrusion 28 into a plane parallel to the flange 25 using a shaped processed portion, the relative arrangement position of the processed portion and the protrusion 28 formed on the flange 25 is slightly shifted. Even if it removes, the removal or thinning of the surface peeling layer 21 of the flange part 25 can be performed accurately.

(2) Since the projecting portion 28 is provided on the opening 24 side of the melt seal portion 26, a portion where the delamination of the flange portion 25 is finished can be formed accurately and easily.

(3) Since the base material layer 20 includes the adhesive layer 22 that can be repeatedly peeled off and adhered to the surface peeling layer 21, the lid member 3 can be repeatedly attached to and detached from the container body 2. Therefore, since the lid member 3 once peeled off can be attached to the container main body 2, the easily openable container 1 can be reused instead of being disposable. Further, the sealing strength after re-adhesion is increased.

(4) In order to manufacture the easy-open container 1, a mold 102 having a protrusion 102 </ b> A is disposed on the opposite side of the cover member 3 of the flange portion 25, and the flange portion 25 is thermoformed by this mold 102 to protrude. A portion 28 was formed, and the surface peeling layer 21 of the projection 28 was removed or thinned, and then the lid member 3 was melt sealed to the flange portion 25. Therefore, since the mold 102 is used to form the protrusions 28 on the container body 2, the protrusions 28 having the same shape can be formed on the flange portions 25 of the container body 2, respectively. Many easy-open containers 1 can be manufactured. Accordingly, the easy-open container 1 can be mass-produced and the cost can be reduced.

(5) In order to remove or thin the surface peeling layer 21 on the protrusion 28, the heating plate 106 is pressed against the protrusion 28. Therefore, the heating plate 106 can easily remove or thin the surface peeling layer by controlling the heating temperature and the pressing time to the protrusion 28.
Since the heating plate 106 is a flat portion having a predetermined area in contact with the projection 28, the position of the heating plate 106 in the approaching / separating direction from the projection 28 or in the direction perpendicular to the direction is determined. Even if there is a slight deviation, the removal or thinning of the surface peeling layer 21 can be carried out without any inconvenience.

(6) In this embodiment, if it is set as the structure provided with the oxygen-absorbing resin layer in the base material layer, the easily openable container 1 with high gas barrier property can be provided.
(7) Since the delamination starts from between the surface peeling layer 21 and the adhesive layer 22 on the outer peripheral edge of the flange 25, there is no need to provide a separate notch in order to start delamination. The manufacturing process of the conductive container 1 is simplified, and the cost of the container can be reduced.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, two protrusions 28 and 29 are provided on the inner peripheral edge and the outer peripheral edge of the flange portion 25, and other configurations are the same as those in the first embodiment. In the description of the second embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.
5A and 5B are schematic views showing an easy-open container 1A according to the second embodiment, in which FIG. 5A is sealed with a lid material 3, and FIG. The state which opened the material 3 is shown, respectively. FIG. 6 is a cross-sectional view of the main part of FIG.

The easily openable container 1A includes a container main body 2A, and the container main body 2A has a flange portion disposed on the periphery of the opening 24 of the container main body 2A with the lid 3 placed on the opening 24. 25 and the lid material 3 are heat-sealed to form an annular melt-sealed portion 26.
The melt seal portion 26 is formed at the center portion of the flange portion 25.
The container body 2 </ b> A is formed of a multilayer sheet composed of three layers of a surface release layer 21, an adhesive layer 22, and a lower layer 23, similarly to the container body 2 of the first embodiment.
In the easy-open container 1A of the present embodiment, the protruding portion 28 and the protruding portion 29 are formed over the entire circumference along the opening 24 of the flange portion 25 while maintaining a predetermined interval, respectively, except for a part of the entire circumference. Has been. The protrusion 29 is formed on the outer peripheral edge side of the melt seal portion 26 with a predetermined distance.

Similar to the protrusion 28, the protrusion 29 has a curved shape so that part of the surface peeling layer 21, the adhesive layer 22 and the lower layer 23 protrudes toward the lid member 3, and of these, the top of the surface peeling layer 21 Is removed, and a part of the adhesive layer 22 is in direct contact with the lid member 3. Similar to the protrusion 28, the protrusion 29 may have a rectangular, cross-sectional, or semicircular cross-sectional shape. In the present embodiment, only the opening start portion of the container is sealed by protruding the protrusion 29.
In the present embodiment, when the lid member 3 is pulled upward (in the direction of the arrow in FIG. 5B), the delamination of the flange portion 25 is a portion P1 from which the top of the surface peeling layer 21 of the protrusion 29 is removed. The process starts at the position P2 and ends at the portion P2 where the top of the surface peeling layer 21 of the protrusion 28 is removed.

FIG.7 and FIG.8 is a schematic block diagram which shows a part of manufacturing apparatus of an easily openable container, respectively.
In FIG. 7, the easily openable container manufacturing apparatus includes a protruding portion forming apparatus 100 that forms a protruding portion 28 on the flange portion 25 of the container body 2A.
The protrusion forming apparatus 100 is different from the protrusion forming apparatus 100 of the first embodiment in that two protrusions 102A are formed on the mold 102, but the other configuration is the same as that of the first embodiment. .
In FIG. 8, the easy-open container manufacturing apparatus includes a protrusion removing device 101 that removes the protrusions 28 and 29 formed by the protrusion forming apparatus 100, and further includes a seal member 7 and a seal member 7 shown in FIG. A bucket (not shown) is provided.
The protrusion removing device 101 includes a heating plate 106 that can come into contact with the top of the protrusion 28. In the present embodiment, the heating plate 106 includes a processed surface having a width that is larger than the dimensions of the adjacent protrusions 28 and 29, and can be moved closer to and away from the protrusions 28 and 29.

According to the second embodiment, the same effects as (1) to (6) of the first embodiment can be obtained, and the following effects can be obtained.
(8) Since the protruding portion 29 is provided on the outer peripheral edge side of the flange portion 25 with respect to the melt seal portion 26, a portion where the delamination of the flange portion 25 is started can be accurately and easily formed.
(9) Since the heating plate 106 has a structure that presses the two protrusions 28 and 29 simultaneously, the surface peeling layers 21 of the two protrusions 28 and 29 can be formed at the same time. The production efficiency of the container 1A is improved.

[Modification of Embodiment]
The aspect described above shows one aspect of the present invention, and the present invention is not limited to the above-described embodiment, and has the configuration of the present invention and can achieve the objects and effects. It goes without saying that modifications and improvements within the scope are included in the content of the present invention. Further, the specific structure, shape, and the like in carrying out the present invention are not problematic as other structures, shapes, and the like as long as the objects and effects of the present invention can be achieved. The present invention is not limited to the above-described embodiments, and modifications and improvements within the scope that can achieve the object of the present invention are included in the present invention.

For example, in the above-described embodiment, the shape of the easy-open container 1 or 1A is a flat rectangular shape, but may be a flat circular shape in the present invention.
Furthermore, in the embodiment, the heating plate 106 is used to remove or thin the surface peeling layer 21 on the protrusions 28 and 29. However, in the present invention, ultrasonic processing, laser processing, or the flange portion 25 is used. The surface peeling layer 21 may be removed or thinned by cutting using a rotary blade that rotates in a plane parallel to the plane.
And in this invention, you may use an ultrasonic wave and an adhesive agent as a means to seal the cover material 3 to the flange part 25. FIG.
In the present invention, only the protrusion 29 may be formed, and a cut may be used instead of the protrusion 28.

  EXAMPLES Next, although an Example and a comparative example are given and this invention is demonstrated in more detail, this invention is not restrict | limited at all to description content, such as these Examples.

[Example]
Using the following materials and methods, an easy-open container having an overall shape shown in FIG. 1 was produced.
(1) Production of container body 2:
The following 6-layer sheet was manufactured by a general distributor type co-extrusion multilayer sheet manufacturing apparatus.
HDPE (50 μm) / Blend layer with HPP and LDPE ratio of 8: 2 / Adhesive layer (10 μm) / EVOH (40 μm) / Adhesive layer (10 μm) / Blend layer with ratio of HPP and LDPE of 8: 2 HDPE Is the surface peeling layer 21, and the other layer is the base material layer 20.
Here, the used resin is as follows.
HDPE: HDPE made of prime polymer, 440M (MI = 0.87, density = 0.951)
HPP: Prime polymer HPP, E-105GM (MI = 0.50, density = 0.90)
LDPE: Japanese polyethylene LDPE, FZ038 (MI = 0.30, density = 0.92)
Adhesive layer: Maleic anhydride-modified PP, Modic AP, P502 (MI = 1.30, density = 0.89) manufactured by Mitsubishi Chemical
EVOH: Kuraray ethylene-vinyl alcohol copolymer resin, Eval J (ethylene 32 mol%, density = 1.17)

Next, the container body 2 shown in FIGS. 1 and 3 was formed by plug-assisted vacuum forming using this multilayer sheet. The container body 2 has a rectangular shape with a contour of 140 mm in length and 120 mm in width, and a height of 28 mm. A flange portion 25 having a width of 15 mm with respect to the opening 24 is formed, and is formed in a substantially rectangular tray shape.
Further, the protrusion portion 28 was formed on the flange portion 25 with the mold 102. The container body 2 having the protrusions 28 formed on the flange portion 25 is fixed to the bucket, and the heating plate 106 whose surface is processed with Teflon (registered trademark) is pressed against the flange portion 25 at 150 ° C., 100 kg load for 1 second, A part of the surface peeling layer 21 was removed.

The lid member 3 having the following configuration is placed on the flange portion 25 at the periphery of the opening 24 of the container body 2 thus obtained, and the easy-open container 1 is manufactured using the following sealing conditions. did.
(Configuration of the lid 3)
Transparent vapor-deposited polyethylene terephthalate (PET) (12 μm) / ONy; polyamide (nylon) (15 μm) / L-LDPE (50 μm)
(Sealing conditions)
Sealing temperature: 200 ° C
Seal pressure: 100kg load Time: 1.0 seconds

(Evaluation results)
As a result of cutting the flange portion 25 of the container body 2 before melting and sealing the lid material 3 and observing the cross section with a microscope, only the surface peeling layer 21 on the top of the projection 28 is removed. It was not destroyed (see FIG. 2).
When the lid member 3 was melt-sealed to the container body 2 and the lid member 3 was opened from the flange portion 25, the tensile strength in the direction perpendicular to the flange portion 25 was as small as 8N. The peeled surface after opening was smooth and clean.
An adhesive processed rubber sheet piece was affixed to the lid 3 side after melt sealing, a needle was inserted therein, and a puncture pressure test was performed. As a result, it was 0.04 MPa, and the strength was much higher than the recommended value of 0.02 MPa for the JISZ0238 retort container.

[Comparative Example 1]
The container main body was manufactured using the metal mold | die and multilayer sheet which were used in the Example. However, unlike the example, the surface peeling layer 21 of the protrusion 28 was not removed or thinned using a heating plate. The container was covered with the same lid material 3 as in the example. First, the projecting portion 28 and the lid material 3 were melt-sealed, and then the flange portion 25 excluding the projecting portion 28 and the lid material 3 were melt-sealed.
In Comparative Example 1, as a result of performing the same puncture pressure test as in the example, a high value of 0.04 MPa was shown. However, when the lid member 3 is pulled from the flange portion 25, the top portion of the protruding portion 28 is the one where delamination is started between the surface peeling layer 21 and the base material layer 20 from the outer peripheral edge portion of the flange portion 25 of the container body 2. Since the surface peeling layer 21 could not be cut even in the vicinity, it could not be opened to the end.

[Comparative Example 2]
An easy-open container 1 similar to Comparative Example 1 was produced except that the thickness of the surface release layer 21 of the multilayer sheet used in the examples was 15 μm.
In Comparative Example 2, opening could be easily performed, but as a result of performing the same puncture pressure test as in the example, it was as low as 0.01 MPa, which was lower than the value recommended for the JIS Z0238 retort container.

[Comparative Example 3]
The flange 102 having no protrusion 28 was formed by using a flat surface mold without the protrusion 102A of the mold 102 used in the example. The multilayer sheet is the same as in the examples.
At the corner of the opening of the flange portion of the container body obtained, locally at the boundary position between the outer peripheral edge portion of the flange portion corresponding to the delamination start site of the container main body and the inner peripheral edge portion of the flange portion corresponding to the delamination end position A missing portion of the seal layer was formed. This is because the surface pressure is 10 kg / cm ² by a ring-shaped pressing member having a protruding portion having a length of 10 mm and a width of 4 mm on the inner peripheral surface of the missing portion forming portion and the other inner peripheral surface having the same width as the flange portion. It is what was pressed with.
The lid body was melted in the same manner as in the example, and then opened. In Comparative Example 3, delamination starts from the outer peripheral edge of the flange portion, and the lid material is separated from the container body at the protruding portion missing portion, but after passing through the missing portion, the surface peeling layer extends and the unsealed feeling is poor. The extended resin layer adhered to the flange after opening, and was dirty.
Therefore, the easy-open containers obtained in Comparative Examples 1 to 3 do not have easy-opening properties and high sealing performance, but the present invention has high sealing properties and easy-opening properties obtained in Examples. It was inferior to the easily openable container.

  The easy-open container of the present invention has both high sealability and easy-openability, and provides an easy-open container that can be widely used as a packaging container for various foods such as retort foods, medicines, cosmetics, etc. To do.

It is the figure which showed the easily openable container in 1st Embodiment of this invention, Comprising: (A) is the state sealed with the cover material, (B) is the schematic which shows the state which opened the cover material from the opening start part. It is. It is principal part sectional drawing of the easily openable container in 1st Embodiment. It is a schematic block diagram which shows the principal part of the one part apparatus which comprises the manufacturing apparatus of the easily openable container in 1st Embodiment. It is a schematic block diagram which shows the principal part of the one part apparatus which comprises the manufacturing apparatus of the easily openable container in 1st Embodiment. It is the figure which showed the easily openable container in 2nd Embodiment of this invention, Comprising: (A) is the state sealed with the cover material, (B) is the schematic which shows the state which opened the cover material from the opening start part. It is. It is principal part sectional drawing of the easily openable container in 2nd Embodiment. It is a schematic block diagram which shows the principal part of the one part apparatus which comprises the manufacturing apparatus of the easily openable container in 2nd Embodiment. It is a schematic block diagram which shows the principal part of the one part apparatus which comprises the manufacturing apparatus of the easily openable container in 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1A ... Easy-open container 2, 2A ... Container main body 3 ... Cover material 20 ... Base material layer 21 ... Surface peeling layer 22 ... Adhesive layer 23 ... Lower layer 24 ... Opening 25 ... Flange part 26 ... Melt seal part 28, 29 ... Projection 102 ... Mold 106 ... Heating plate

Claims (9)

A flange body is provided on the periphery of the opening, and a container body formed of a multilayer sheet and a lid member melt-sealed by the flange part of the container body are provided, and the multilayer sheet is bonded to the lid member It has a surface peeling layer and a base material layer to be bonded to the surface peeling layer, and the adhesive force between the surface peeling layer and the base material layer of the container body is a fusion between the surface peeling layer and the lid material. An easy-open container formed smaller than the adhesive strength of the seal part,
An easily openable container characterized in that a surface peeling layer of a protrusion provided in advance in a position different from the melt seal portion in the surface peeling layer of the flange portion is removed or thinned. In the easy-open container described in claim 1,
The easily openable container, wherein the protrusion is provided closer to the opening than the melt seal. In the easy-open container described in claim 1 or 2,
The easily openable container characterized in that the protruding portion is provided on the flange outer edge side opposite to the opening side from the melt seal portion. In the easily openable container according to any one of claims 1 to 3,
The said base material layer is provided with the adhesion layer which can be repeatedly peeled and adhered to the said surface peeling layer, The easily openable container characterized by the above-mentioned. In the easily openable container according to any one of claims 1 to 4,
The said base material layer is equipped with an oxygen absorptive resin layer, The easily openable container characterized by the above-mentioned. A container body that is provided with a flange portion at the periphery of the opening and is formed of a multilayer sheet and can be melt-sealed with a lid material at the flange portion,
The multilayer sheet has a surface peeling layer bonded to the lid member and a base material layer bonded to the surface peeling layer, and an adhesive force between the surface peeling layer and the base material layer of the container body is Formed smaller than the adhesive force between the surface release layer and the lid,
A container body, wherein a surface peeling layer of a protrusion provided in advance in a position different from the melt seal portion in the surface peeling layer of the flange portion is removed or thinned. A method for producing an easily openable container according to any one of claims 1 to 5,
A mold having a protrusion is disposed on the flange portion opposite to the lid member, and the flange portion is thermoformed with the mold to form the protrusion, and the surface peeling layer of the protrusion is removed or A method for producing an easily openable container, characterized in that the container is thinned and then a lid material is melt-sealed on the flange portion. In the manufacturing method of the easily openable container described in Claim 7,
A method for producing an easily openable container, wherein a heating plate is pressed against the protruding portion in order to remove or thin the surface peeling layer on the protruding portion. An apparatus for producing an easily openable container according to any one of claims 1 to 5,
A mold having a projection disposed on the opposite side of the lid of the flange portion; a heating plate capable of contacting the projection portion to remove or thin the surface peeling layer of the flange portion; and the flange portion And a sealing member for melting and sealing the lid member.

Images